Thermodynamic and kinetic studies on CO2 capture with Poly[VBTMA][Arg

NASA Astrophysics Data System (ADS)

Raja Shahrom, Maisara Shahrom; Wilfred, Cecilia Devi; Chong, Fai Kait

2018-05-01

This paper discusses the technologies for capturing CO2 from the natural gas using poly[VBTMA][Arg], a type of poly(ionic liquids) with an amino acid as the anion. The results revealed that the CO2 uptake increased from 3.23 mmol/g to 7.91 mmol/g at 1-10 bar, 298 K due to both chemical absorption and physical adsorption increments. Four adsorption isotherm models were applied to study the interaction between adsorbate and adsorbent to study the physical adsorption i.e. Freundlich, Langmuir, Dubinin Raduschkevich and Temkin isotherms at 298 K, 313 K and 333 K. Promising results were obtained that suggested the Freundlich model and the pseudo-first order model are well fitted with the kinetic data at 298 K with a 0.9943 R2 value. This study has provided empirical evidence to the current body of knowledge pertaining to CO2 capture technologies.

Human health risk assessment of nitrosamines and nitramines for potential application in CO2 capture.

PubMed

Ravnum, S; Rundén-Pran, E; Fjellsbø, L M; Dusinska, M

2014-07-01

Emission and accumulation of carbon dioxide (CO2) in the atmosphere exert an environmental and climate change challenge. An attempt to deal with this challenge is made at Mongstad by application of amines for CO2 capture and storage (CO2 capture Mongstad (CCM) project). As part of the CO2 capture process, nitrosamines and nitramines may be emitted. Toxicological testing of nitrosamines and nitramines indicate a genotoxic potential of these substances. Here we present a risk characterization and assessment for five nitrosamines (N-Nitrosodi-methylamine (NDMA) N-Nitrosodi-ethylamine (NDEA), N-Nitroso-morpholine (NNM), N-Nitroso-piperidine (NPIP), and Dinitroso-piperazine (DNP)) and two nitramines (N-Methyl-nitramine (NTMA), Dimethyl-nitramine (NDTMA)), which are potentially emitted from the CO2 capture plant (CCP). Human health risk assessment of genotoxic non-threshold substances is a heavily debated topic, and no consensus methodology exists internationally. Extrapolation modeling from high-dose animal exposures to low-dose human exposures can be crucial for the final risk calculation. In the work presented here, different extrapolation models are discussed, and suggestions on applications are given. Then, preferred methods for calculating derived minimal effect level (DMEL) are presented with the selected nitrosamines and nitramines. Copyright © 2014 Elsevier Inc. All rights reserved.

Evaluation of the impact of H2O, O2, and SO2 on postcombustion CO2 capture in metal-organic frameworks.

PubMed

Yu, Jiamei; Ma, Yuguang; Balbuena, Perla B

2012-05-29

Molecular modeling methods are used to estimate the influence of impurity species: water, O(2), and SO(2) in flue gas mixtures present in postcombustion CO(2) capture using a metal organic framework, HKUST-1, as a model sorbent material. Coordinated and uncoordinated water effects on CO(2) capture are analyzed. Increase of CO(2) adsorption is observed for both cases, which can be attributed to the enhanced binding energy between CO(2) and HKUST-1 due to the introduction of a small amount of water. Density functional theory calculations indicate that the binding energy between CO(2) and HKUST-1 with coordinated water is ~1 kcal/mol higher than that without coordinated water. It is found that the improvement of CO(2)/N(2) selectivity induced by coordinated water may mainly be attributed to the increased CO(2) adsorption on the hydrated HKUST-1. On the other hand, the enhanced selectivity induced by uncoordinated water in the flue gas mixture can be explained on the basis of the competition of adsorption sites between water and CO(2) (N(2)). At low pressures, a significant CO(2)/N(2) selectivity increase is due to the increase of CO(2) adsorption and decrease of N(2) adsorption as a consequence of competition of adsorption sites between water and N(2). However, with more water molecules adsorbed at higher pressures, the competition between water and CO(2) leads to the decrease of CO(2) adsorption capacity. Therefore, high pressure operation should be avoided in HKUST-1 sorbents for CO(2) capture. In addition, the effects of O(2) and SO(2) on CO(2) capture in HKUST-1 are investigated: The CO(2)/N(2) selectivity does not change much even with relatively high concentrations of O(2) in the flue gas (up to 8%). A slightly lower CO(2)/N(2) selectivity of a CO(2)/N(2)/H(2)O/SO(2) mixture is observed compared with that in a CO(2)/N(2)/H(2)O mixture, especially at high pressures, due to the strong SO(2) binding with HKUST-1.

A simulation study on the abatement of CO2 emissions by de-absorption with monoethanolamine.

PubMed

Greer, T; Bedelbayev, A; Igreja, J M; Gomes, J F; Lie, B

2010-01-01

Because of the adverse effect of CO2 from fossil fuel combustion on the earth's ecosystems, the most cost-effective method for CO2 capture is an important area of research. The predominant process for CO2 capture currently employed by industry is chemical absorption in amine solutions. A dynamic model for the de-absorption process was developed with monoethanolamine (MEA) solution. Henry's law was used for modelling the vapour phase equilibrium of the CO2, and fugacity ratios calculated by the Peng-Robinson equation of state (EOS) were used for H2O, MEA, N2 and O2. Chemical reactions between CO2 and MEA were included in the model along with the enhancement factor for chemical absorption. Liquid and vapour energy balances were developed to calculate the liquid and vapour temperature, respectively.

Modeling Amorphous Microporous Polymers for CO2 Capture and Separations.

PubMed

Kupgan, Grit; Abbott, Lauren J; Hart, Kyle E; Colina, Coray M

2018-06-13

This review concentrates on the advances of atomistic molecular simulations to design and evaluate amorphous microporous polymeric materials for CO 2 capture and separations. A description of atomistic molecular simulations is provided, including simulation techniques, structural generation approaches, relaxation and equilibration methodologies, and considerations needed for validation of simulated samples. The review provides general guidelines and a comprehensive update of the recent literature (since 2007) to promote the acceleration of the discovery and screening of amorphous microporous polymers for CO 2 capture and separation processes.

Simulating carbon capture by enhanced weathering with croplands: an overview of key processes highlighting areas of future model development

PubMed Central

Quegan, Shaun; Banwart, Steven A.

2017-01-01

Enhanced weathering (EW) aims to amplify a natural sink for CO2 by incorporating powdered silicate rock with high reactive surface area into agricultural soils. The goal is to achieve rapid dissolution of minerals and release of alkalinity with accompanying dissolution of CO2 into soils and drainage waters. EW could counteract phosphorus limitation and greenhouse gas (GHG) emissions in tropical soils, and soil acidification, a common agricultural problem studied with numerical process models over several decades. Here, we review the processes leading to soil acidification in croplands and how the soil weathering CO2 sink is represented in models. Mathematical models capturing the dominant processes and human interventions governing cropland soil chemistry and GHG emissions neglect weathering, while most weathering models neglect agricultural processes. We discuss current approaches to modelling EW and highlight several classes of model having the potential to simulate EW in croplands. Finally, we argue for further integration of process knowledge in mathematical models to capture feedbacks affecting both longer-term CO2 consumption and crop growth and yields. PMID:28381633

The system-wide economics of a carbon dioxide capture, utilization, and storage network: Texas Gulf Coast with pure CO2-EOR flood

NASA Astrophysics Data System (ADS)

King, Carey W.; Gülen, Gürcan; Cohen, Stuart M.; Nuñez-Lopez, Vanessa

2013-09-01

This letter compares several bounding cases for understanding the economic viability of capturing large quantities of anthropogenic CO2 from coal-fired power generators within the Electric Reliability Council of Texas electric grid and using it for pure CO2 enhanced oil recovery (EOR) in the onshore coastal region of Texas along the Gulf of Mexico. All captured CO2 in excess of that needed for EOR is sequestered in saline formations at the same geographic locations as the oil reservoirs but at a different depth. We analyze the extraction of oil from the same set of ten reservoirs within 20- and five-year time frames to describe how the scale of the carbon dioxide capture, utilization, and storage (CCUS) network changes to meet the rate of CO2 demand for oil recovery. Our analysis shows that there is a negative system-wide net present value (NPV) for all modeled scenarios. The system comes close to breakeven economics when capturing CO2 from three coal-fired power plants to produce oil via CO2-EOR over 20 years and assuming no CO2 emissions penalty. The NPV drops when we consider a larger network to produce oil more quickly (21 coal-fired generators with CO2 capture to produce 80% of the oil within five years). Upon applying a CO2 emissions penalty of 602009/tCO2 to fossil fuel emissions to ensure that coal-fired power plants with CO2 capture remain in baseload operation, the system economics drop significantly. We show near profitability for the cash flow of the EOR operations only; however, this situation requires relatively cheap electricity prices during operation.

Computational Modeling of Mixed Solids for CO2 CaptureSorbents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duan, Yuhua

2015-01-01

Since current technologies for capturing CO2 to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO2 reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO2 capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO2 sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of differentmore » classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO2 adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO2 capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO2 sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO2 capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we apply our screening methodology to mixing solid systems to adjust the turnover temperature to help on developing CO2 capture Technologies.« less

Assessment of Solid Sorbent Systems for Post-Combustion Carbon Dioxide Capture at Coal-Fired Power Plants

NASA Astrophysics Data System (ADS)

Glier, Justin C.

In an effort to lower future CO2 emissions, a wide range of technologies are being developed to scrub CO2 from the flue gases of fossil fuel-based electric power and industrial plants. This thesis models one of several early-stage post-combustion CO2 capture technologies, solid sorbent-based CO2 capture process, and presents performance and cost estimates of this system on pulverized coal power plants. The spreadsheet-based software package Microsoft Excel was used in conjunction with AspenPlus modelling results and the Integrated Environmental Control Model to develop performance and cost estimates for the solid sorbent-based CO2 capture technology. A reduced order model also was created to facilitate comparisons among multiple design scenarios. Assumptions about plant financing and utilization, as well as uncertainties in heat transfer and material design that affect heat exchanger and reactor design were found to produce a wide range of cost estimates for solid sorbent-based systems. With uncertainties included, costs for a supercritical power plant with solid sorbent-based CO2 capture ranged from 167 to 533 per megawatt hour for a first-of-a-kind installation (with all costs in constant 2011 US dollars) based on a 90% confidence interval. The median cost was 209/MWh. Post-combustion solid sorbent-based CO2 capture technology is then evaluated in terms of the potential cost for a mature system based on historic experience as technologies are improved with sequential iterations of the currently available system. The range costs for a supercritical power plant with solid sorbent-based CO2 capture was found to be 118 to 189 per megawatt hour with a nominal value of 163 per megawatt hour given the expected range of technological improvement in the capital and operating costs and efficiency of the power plant after 100 GW of cumulative worldwide experience. These results suggest that the solid sorbent-based system will not be competitive with currently available liquid amine-systems in the absence of significant new improvements in solid sorbent properties and process system design to reduce the heat exchange surface area in the regenerator and cross-flow heat exchanger. Finally, the importance of these estimates for policy makers is discussed.

Near-term deployment of carbon capture and sequestration from biorefineries in the United States.

PubMed

Sanchez, Daniel L; Johnson, Nils; McCoy, Sean T; Turner, Peter A; Mach, Katharine J

2018-05-08

Capture and permanent geologic sequestration of biogenic CO 2 emissions may provide critical flexibility in ambitious climate change mitigation. However, most bioenergy with carbon capture and sequestration (BECCS) technologies are technically immature or commercially unavailable. Here, we evaluate low-cost, commercially ready CO 2 capture opportunities for existing ethanol biorefineries in the United States. The analysis combines process engineering, spatial optimization, and lifecycle assessment to consider the technical, economic, and institutional feasibility of near-term carbon capture and sequestration (CCS). Our modeling framework evaluates least cost source-sink relationships and aggregation opportunities for pipeline transport, which can cost-effectively transport small CO 2 volumes to suitable sequestration sites; 216 existing US biorefineries emit 45 Mt CO 2 annually from fermentation, of which 60% could be captured and compressed for pipeline transport for under $25/tCO 2 A sequestration credit, analogous to existing CCS tax credits, of $60/tCO 2 could incent 30 Mt of sequestration and 6,900 km of pipeline infrastructure across the United States. Similarly, a carbon abatement credit, analogous to existing tradeable CO 2 credits, of $90/tCO 2 can incent 38 Mt of abatement. Aggregation of CO 2 sources enables cost-effective long-distance pipeline transport to distant sequestration sites. Financial incentives under the low-carbon fuel standard in California and recent revisions to existing federal tax credits suggest a substantial near-term opportunity to permanently sequester biogenic CO 2 This financial opportunity could catalyze the growth of carbon capture, transport, and sequestration; improve the lifecycle impacts of conventional biofuels; support development of carbon-negative fuels; and help fulfill the mandates of low-carbon fuel policies across the United States. Copyright © 2018 the Author(s). Published by PNAS.

Near-term deployment of carbon capture and sequestration from biorefineries in the United States

PubMed Central

Johnson, Nils; McCoy, Sean T.; Turner, Peter A.; Mach, Katharine J.

2018-01-01

Capture and permanent geologic sequestration of biogenic CO2 emissions may provide critical flexibility in ambitious climate change mitigation. However, most bioenergy with carbon capture and sequestration (BECCS) technologies are technically immature or commercially unavailable. Here, we evaluate low-cost, commercially ready CO2 capture opportunities for existing ethanol biorefineries in the United States. The analysis combines process engineering, spatial optimization, and lifecycle assessment to consider the technical, economic, and institutional feasibility of near-term carbon capture and sequestration (CCS). Our modeling framework evaluates least cost source–sink relationships and aggregation opportunities for pipeline transport, which can cost-effectively transport small CO2 volumes to suitable sequestration sites; 216 existing US biorefineries emit 45 Mt CO2 annually from fermentation, of which 60% could be captured and compressed for pipeline transport for under $25/tCO2. A sequestration credit, analogous to existing CCS tax credits, of $60/tCO2 could incent 30 Mt of sequestration and 6,900 km of pipeline infrastructure across the United States. Similarly, a carbon abatement credit, analogous to existing tradeable CO2 credits, of $90/tCO2 can incent 38 Mt of abatement. Aggregation of CO2 sources enables cost-effective long-distance pipeline transport to distant sequestration sites. Financial incentives under the low-carbon fuel standard in California and recent revisions to existing federal tax credits suggest a substantial near-term opportunity to permanently sequester biogenic CO2. This financial opportunity could catalyze the growth of carbon capture, transport, and sequestration; improve the lifecycle impacts of conventional biofuels; support development of carbon-negative fuels; and help fulfill the mandates of low-carbon fuel policies across the United States. PMID:29686063

Carbon Capture and Utilization in the Industrial Sector.

PubMed

Psarras, Peter C; Comello, Stephen; Bains, Praveen; Charoensawadpong, Panunya; Reichelstein, Stefan; Wilcox, Jennifer

2017-10-03

The fabrication and manufacturing processes of industrial commodities such as iron, glass, and cement are carbon-intensive, accounting for 23% of global CO 2 emissions. As a climate mitigation strategy, CO 2 capture from flue gases of industrial processes-much like that of the power sector-has not experienced wide adoption given its high associated costs. However, some industrial processes with relatively high CO 2 flue concentration may be viable candidates to cost-competitively supply CO 2 for utilization purposes (e.g., polymer manufacturing, etc.). This work develops a methodology that determines the levelized cost ($/tCO 2 ) of separating, compressing, and transporting carbon dioxide. A top-down model determines the cost of separating and compressing CO 2 across 18 industrial processes. Further, the study calculates the cost of transporting CO 2 via pipeline and tanker truck to appropriately paired sinks using a bottom-up cost model and geo-referencing approach. The results show that truck transportation is generally the low-cost alternative given the relatively small volumes (ca. 100 kt CO 2 /a). We apply our methodology to a regional case study in Pennsylvania, which shows steel and cement manufacturing paired to suitable sinks as having the lowest levelized cost of capture, compression, and transportation.

Hierarchical calibration and validation for modeling bench-scale solvent-based carbon capture. Part 1: Non-reactive physical mass transfer across the wetted wall column: Original Research Article: Hierarchical calibration and validation for modeling bench-scale solvent-based carbon capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Xu, Zhijie; Lai, Canhai

A hierarchical model calibration and validation is proposed for quantifying the confidence level of mass transfer prediction using a computational fluid dynamics (CFD) model, where the solvent-based carbon dioxide (CO2) capture is simulated and simulation results are compared to the parallel bench-scale experimental data. Two unit problems with increasing level of complexity are proposed to breakdown the complex physical/chemical processes of solvent-based CO2 capture into relatively simpler problems to separate the effects of physical transport and chemical reaction. This paper focuses on the calibration and validation of the first unit problem, i.e. the CO2 mass transfer across a falling ethanolaminemore » (MEA) film in absence of chemical reaction. This problem is investigated both experimentally and numerically using nitrous oxide (N2O) as a surrogate for CO2. To capture the motion of gas-liquid interface, a volume of fluid method is employed together with a one-fluid formulation to compute the mass transfer between the two phases. Bench-scale parallel experiments are designed and conducted to validate and calibrate the CFD models using a general Bayesian calibration. Two important transport parameters, e.g. Henry’s constant and gas diffusivity, are calibrated to produce the posterior distributions, which will be used as the input for the second unit problem to address the chemical adsorption of CO2 across the MEA falling film, where both mass transfer and chemical reaction are involved.« less

Comparaison de la performance environnementale de la production thermique d'electricite avec et sans sequestration geologique du dioxyde de carbone

NASA Astrophysics Data System (ADS)

Bellerive, Nathalie

The research project hypothesis is that CO2 capture and sequestration technologies (CSC) leads to a significant decrease in global warming, but increases the impact of all other aspects of the study. This is because other processes used for CO2 capture and sequestration require additional quantities of raw materials and energy. Two other objectives are described in this project. The first is the modeling of an Integrated Gasification Combined Cycle power plant for which there is no known generic data. The second is to select the right hypothesis regarding electrical production technologies, CO2 capture, compression and transportation by pipeline and finally sequestration. "Life Cycle Assessment" (LCA) analyses were chosen for this research project. LCA is an exhaustive quantitative method used to evaluate potential environmental impacts associated with a product, a service or an activity from resource extraction to waste elimination. This tool is governed by ISO 14 040 through ISO 14 049 and is sustained by the Society of Environmental Toxicology and Chemistry (SETAC) and the United Nations Environment Program (UNEP). Two power plants were studied, the Integrated Gasification Combined Cycle (IGCC) power plant and the Natural Gas Combined Cycle (NGCC) power plant. In order to sequester CO2 in geological formation, it is necessary to extract CO2from emission flows. For the IGCC power plant, CO 2 was captured before the burning phase. For the NGCC power plant, the capture was done during the afterburning phase. Once the CO2 was isolated, it was compressed and directed through a transportation pipe 1 000 km in length on the ground surface and in the sea. It is hypothesized that the power plant is 300 km from the shore and the sequestration platform 700 km from France's shore, in the North Sea. The IGCC power plant modeling and data selection regarding CO2 capture and sequestration were done by using primary data from the industry and the Ecoinvent generic database (Version 1.2). This database was selected due to its European source. Finally, technical calculations and literature were used to complete the data inventory. This was validated by electrical experts in order to increase data and modeling precision. Results were similar for IGCC and NGCC power plants using Impact 2002+, an impacts analysis method. Global warming potential decreased by 67% with the implementation of CO2 capture and sequestration compared to systems without CSC. Results for all others impacts categories, demonstrated an increase from 16% to 116% in relative proportions compared to systems without CSC. The main contributor was the additional quantity of energy required to operate CO2 capture and compression facilities. This additional energy negatively affected the power plant's global efficiency because of the increase in the quantity of fossil fuel that needed to be extracted and consumed. The increase in other impacts was mainly due to additional electricity, fossil fuel (for extracting, treatment and transportation) and additional emissions generated during power plant operations. A scenario analysis was done to study the sensitivity and variability of uncertain data during the software modeling process of a power plant. Data on power plant efficiency is the most variable and sensitive during modeling, followed by the length of the transportation pipe and the leaking rate during CO2 sequestration. This result analysis is interesting because it led to the maximum efficiency scenario with capture (with a short CO 2 transportation distance and a low leaking rate) obtaining better results on all impact category indicators, compared to the minimum efficiency scenario without capture. In fact, positive results on all category indicators were possible during the system comparison between the two cases (with and without capture). (Abstract shortened by UMI.)

Amidine-Functionalized Poly(2-vinyl-4,4-dimethylazlactone) for Selective and Efficient CO 2 Fixing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barkakaty, Balaka; Browning, Katie L.; Sumpter, Bobby

Development of novel polymeric materials capable of efficient CO 2 capture and separation under ambient conditions is crucial for cost-effective and practical industrial applications. Here we report the facile synthesis of a new CO 2-responsive polymer through post-polymerization modification of poly(2 vinyl-4,4-dimethylazlactone) (PVDMA). The reactive pendant azlactone groups of PVDMA are easily modified with 4-(N-methyltetrahydropyrimidine) benzyl alcohol (PBA) without any by-product formation. FTIR and TGA experiments show the new PBA functionalized polymer powder can reversibly capture CO 2 at room temperature and under atmospheric pressure. CO2 capture was selective, showing a high fixing efficiency even with a mixed gas systemmore » (20% CO 2, 80% N 2) similar to flue gas. CO 2 release occurred at room temperature and release profiles were investigated as a function of temperature. Density Functional Theory (DFT) calculations coupled with modeling and simulation reveal the presence of two CO 2 binding sites in the PBA functionalized polymer resulting in a two-step CO 2 release at room temperature. Finally, we find that the ease of material preparation, high fixing efficiency, and robust release characteristics suggest that post-polymerization modification may be a useful route to designing new materials for CO 2 capture.« less

Amidine-Functionalized Poly(2-vinyl-4,4-dimethylazlactone) for Selective and Efficient CO 2 Fixing

DOE PAGES

Barkakaty, Balaka; Browning, Katie L.; Sumpter, Bobby; ...

2016-02-12

Development of novel polymeric materials capable of efficient CO 2 capture and separation under ambient conditions is crucial for cost-effective and practical industrial applications. Here we report the facile synthesis of a new CO 2-responsive polymer through post-polymerization modification of poly(2 vinyl-4,4-dimethylazlactone) (PVDMA). The reactive pendant azlactone groups of PVDMA are easily modified with 4-(N-methyltetrahydropyrimidine) benzyl alcohol (PBA) without any by-product formation. FTIR and TGA experiments show the new PBA functionalized polymer powder can reversibly capture CO 2 at room temperature and under atmospheric pressure. CO2 capture was selective, showing a high fixing efficiency even with a mixed gas systemmore » (20% CO 2, 80% N 2) similar to flue gas. CO 2 release occurred at room temperature and release profiles were investigated as a function of temperature. Density Functional Theory (DFT) calculations coupled with modeling and simulation reveal the presence of two CO 2 binding sites in the PBA functionalized polymer resulting in a two-step CO 2 release at room temperature. Finally, we find that the ease of material preparation, high fixing efficiency, and robust release characteristics suggest that post-polymerization modification may be a useful route to designing new materials for CO 2 capture.« less

Structure–property reduced order model for viscosity prediction in single-component CO 2 -binding organic liquids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cantu, David C.; Malhotra, Deepika; Koech, Phillip K.

2016-01-01

CO2 capture from power generation with aqueous solvents remains energy intensive due to the high water content of the current technology, or the high viscosity of non-aqueous alternatives. Quantitative reduced models, connecting molecular structure to bulk properties, are key for developing structure-property relationships that enable molecular design. In this work, we describe such a model that quantitatively predicts viscosities of CO2 binding organic liquids (CO2BOLs) based solely on molecular structure and the amount of bound CO2. The functional form of the model correlates the viscosity with the CO2 loading and an electrostatic term describing the charge distribution between the CO2-bearingmore » functional group and the proton-receiving amine. Molecular simulations identify the proton shuttle between these groups within the same molecule to be the critical indicator of low viscosity. The model, developed to allow for quick screening of solvent libraries, paves the way towards the rational design of low viscosity non-aqueous solvent systems for post-combustion CO2 capture. Following these theoretical recommendations, synthetic efforts of promising candidates and viscosity measurement provide experimental validation and verification.« less

Process and Material Design for Micro-Encapsulated Ionic Liquids in Post-Combustion CO 2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Bo; Brennecke, Joan F; McCready, Mark

Aprotic Heterocyclic Anion (AHA) Ionic Liquids (ILs) have been identified as promising new solvents for post-combustion carbon capture due to their high CO 2 uptake and the high tenability 1,2 of their binding energy with CO 2. Some of these compounds change phase (solid to liquid) on absorption of CO 2; these Phase Change ILs (PCILs)3 offer the additional advantage that part of the heat needed to desorb the CO2 from the absorbent is provided by the heat of fusion as the PCIL solidifies upon release of CO 2. However, the relatively high viscosity of AHA ILs and the occurrencemore » of a phase change in PCILs present challenges for conventional absorption equipment. To overcome these challenges we are pursuing the use of new technology to micro-encapsulate the AHA ILs and PCILs. Our partners at Lawrence Livermore National Laboratory have successfully demonstrated this technology in the application of post-combustion carbon capture with sodium and potassium carbonate solutions,4 and have recently shown the feasibility of micro-encapsulation of an AHA IL for carbon capture.5 The large effective surface area and high CO 2 permeability of the micro-capsules is expected to offset the drawback of the high IL viscosity and to provide for a more efficient and cost-effective mass transfer operation involving AHA ILs and PCILs. These opportunities, however, present us with both process and materials design questions. For example, what is the target CO 2 absorption strength (enthalpy of chemical absorption) for the tunable AHA IL? What is the target for micro-capsule diameter in order to obtain a high mass transfer rate and good fluidization performance? What are the appropriate temperatures and pressures for the absorber and stripper? In order to address these and other questions, we have developed a rate-based model of a post-combustion CO 2 capture process using micro-encapsulated ILs. As a performance baseline, we have also developed a rate-based model of a standard packed bed absorber using an un-encapsulated AHA IL absorbent. Using such models we can determine optimal CO 2 capture performance and investigate the sensitivity of the optimum with respect to the key thermo-physical and transport properties of the IL (e.g., CO 2 binding energy, viscosity, etc.) and the micro-capsules (e.g. diameter, CO 2 permeability, etc.). Results of these process and material design studies will be presented, and the performance of this novel micro-encapsulation technology will be assessed.« less

Dynamic Modeling and Control Studies of a Two-Stage Bubbling Fluidized Bed Adsorber-Reactor for Solid-Sorbent CO{sub 2} Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Modekurti, Srinivasarao; Bhattacharyya, Debangsu; Zitney, Stephen E.

2013-07-31

A one-dimensional, non-isothermal, pressure-driven dynamic model has been developed for a two-stage bubbling fluidized bed (BFB) adsorber-reactor for solid-sorbent carbon dioxide (CO{sub 2}) capture using Aspen Custom Modeler® (ACM). The BFB model for the flow of gas through a continuous phase of downward moving solids considers three regions: emulsion, bubble, and cloud-wake. Both the upper and lower reactor stages are of overflow-type configuration, i.e., the solids leave from the top of each stage. In addition, dynamic models have been developed for the downcomer that transfers solids between the stages and the exit hopper that removes solids from the bottom ofmore » the bed. The models of all auxiliary equipment such as valves and gas distributor have been integrated with the main model of the two-stage adsorber reactor. Using the developed dynamic model, the transient responses of various process variables such as CO{sub 2} capture rate and flue gas outlet temperatures have been studied by simulating typical disturbances such as change in the temperature, flowrate, and composition of the incoming flue gas from pulverized coal-fired power plants. In control studies, the performance of a proportional-integral-derivative (PID) controller, feedback-augmented feedforward controller, and linear model predictive controller (LMPC) are evaluated for maintaining the overall CO{sub 2} capture rate at a desired level in the face of typical disturbances.« less

Mathematical programming (MP) model to determine optimal transportation infrastructure for geologic CO2 storage in the Illinois basin

NASA Astrophysics Data System (ADS)

Rehmer, Donald E.

Analysis of results from a mathematical programming model were examined to 1) determine the least cost options for infrastructure development of geologic storage of CO2 in the Illinois Basin, and 2) perform an analysis of a number of CO2 emission tax and oil price scenarios in order to implement development of the least-cost pipeline networks for distribution of CO2. The model, using mixed integer programming, tested the hypothesis of whether viable EOR sequestration sites can serve as nodal points or hubs to expand the CO2 delivery infrastructure to more distal locations from the emissions sources. This is in contrast to previous model results based on a point-to- point model having direct pipeline segments from each CO2 capture site to each storage sink. There is literature on the spoke and hub problem that relates to airline scheduling as well as maritime shipping. A large-scale ship assignment problem that utilized integer linear programming was run on Excel Solver and described by Mourao et al., (2001). Other literature indicates that aircraft assignment in spoke and hub routes can also be achieved using integer linear programming (Daskin and Panayotopoulos, 1989; Hane et al., 1995). The distribution concept is basically the reverse of the "tree and branch" type (Rothfarb et al., 1970) gathering systems for oil and natural gas that industry has been developing for decades. Model results indicate that the inclusion of hubs as variables in the model yields lower transportation costs for geologic carbon dioxide storage over previous models of point-to-point infrastructure geometries. Tabular results and GIS maps of the selected scenarios illustrate that EOR sites can serve as nodal points or hubs for distribution of CO2 to distal oil field locations as well as deeper saline reservoirs. Revenue amounts and capture percentages both show an improvement over solutions when the hubs are not allowed to come into the solution. Other results indicate that geologic storage of CO2 into saline aquifers does not come into solutions selected by the model until the CO 2 emissions tax approaches 50/tonne. CO2 capture and storage begins to occur when the oil price is above 24.42 a barrel based on the constraints of the model. The annual storage capacity of the basin is nearly maximized when the net price of oil is as low as 40 per barrel and the CO2 emission tax is 60/tonne. The results from every subsequent scenario that was examined by this study demonstrate that EOR utilizing anthropogenically captured CO2 will earn net revenue, and thus represents an economically viable option for CO2 storage in the Illinois Basin.

Solvent-free nanofluid with three structure models based on the composition of a MWCNT/SiO2 core and its adsorption capacity of CO2

NASA Astrophysics Data System (ADS)

Yang, R. L.; Zheng, Y. P.; Wang, T. Y.; Li, P. P.; Wang, Y. D.; Yao, D. D.; Chen, L. X.

2018-01-01

A series of core/shell nanoparticle organic/inorganic hybrid materials (NOHMs) with different weight ratios of two components, consisting of multi-walled carbon nanotubes (MWCNTs) and silicon dioxide (SiO2) as the core were synthesized. The NOHMs display a liquid-like state in the absence of solvent at room temperature. Five NOHMs were categorized into three kinds of structure states based on different weight ratio of two components in the core, named the power strip model, the critical model and the collapse model. The capture capacities of these NOHMs for CO2 were investigated at 298 K and CO2 pressures ranging from 0 to 5 MPa. Compared with NOHMs having a neat MWCNT core, it was revealed that NOHMs with the power strip model show better adsorption capacity toward CO2 due to its lower viscosity and more reactive groups that can react with CO2. In addition, the capture capacities of NOHMs with the critical model were relatively worse than the neat MWCNT-based NOHM. The result is attributed to the aggregation of SiO2 in these samples, which may cause the consumption and hindrance of reactive groups. However, the capture capacity of NOHMs with the collapse model was the worst of all the NOHMs, owing to its lowest content of reactive groups and hollow structure in MWCNTs. In addition, they presented non-interference of MWCNTs and SiO2 without aggregation state.

Conceptual Design of Optimized Fossil Energy Systems with Capture and Sequestration of Carbon Dioxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nils Johnson; Joan Ogden

2010-12-31

In this final report, we describe research results from Phase 2 of a technical/economic study of fossil hydrogen energy systems with carbon dioxide (CO{sub 2}) capture and storage (CCS). CO{sub 2} capture and storage, or alternatively, CO{sub 2} capture and sequestration, involves capturing CO{sub 2} from large point sources and then injecting it into deep underground reservoirs for long-term storage. By preventing CO{sub 2} emissions into the atmosphere, this technology has significant potential to reduce greenhouse gas (GHG) emissions from fossil-based facilities in the power and industrial sectors. Furthermore, the application of CCS to power plants and hydrogen production facilitiesmore » can reduce CO{sub 2} emissions associated with electric vehicles (EVs) and hydrogen fuel cell vehicles (HFCVs) and, thus, can also improve GHG emissions in the transportation sector. This research specifically examines strategies for transitioning to large-scale coal-derived energy systems with CCS for both hydrogen fuel production and electricity generation. A particular emphasis is on the development of spatially-explicit modeling tools for examining how these energy systems might develop in real geographic regions. We employ an integrated modeling approach that addresses all infrastructure components involved in the transition to these energy systems. The overall objective is to better understand the system design issues and economics associated with the widespread deployment of hydrogen and CCS infrastructure in real regions. Specific objectives of this research are to: Develop improved techno-economic models for all components required for the deployment of both hydrogen and CCS infrastructure, Develop novel modeling methods that combine detailed spatial data with optimization tools to explore spatially-explicit transition strategies, Conduct regional case studies to explore how these energy systems might develop in different regions of the United States, and Examine how the design and cost of coal-based H{sub 2} and CCS infrastructure depend on geography and location.« less

Pilot testing of a membrane system for postcombustion CO 2 capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Merkel, Tim; Kniep, Jay; Wei, Xiaotong

2015-09-30

This final report summarizes work conducted for the U.S. Department of Energy, National Energy Technology Laboratory (DOE) to scale up an efficient post-combustion CO 2 capture membrane process to the small pilot test stage (award number DE-FE0005795). The primary goal of this research program was to design, fabricate, and operate a membrane CO 2 capture system to treat coal-derived flue gas containing 20 tonnes CO 2/day (20 TPD). Membrane Technology and Research (MTR) conducted this project in collaboration with Babcock and Wilcox (B&W), the Electric Power Research Institute (EPRI), WorleyParsons (WP), the Illinois Sustainable Technology Center (ISTC), Enerkem (EK), andmore » the National Carbon Capture Center (NCCC). In addition to the small pilot design, build and slipstream testing at NCCC, other project efforts included laboratory membrane and module development at MTR, validation field testing on a 1 TPD membrane system at NCCC, boiler modeling and testing at B&W, a techno-economic analysis (TEA) by EPRI/WP, a case study of the membrane technology applied to a ~20 MWe power plant by ISTC, and an industrial CO 2 capture test at an Enerkem waste-to-biofuel facility. The 20 TPD small pilot membrane system built in this project successfully completed over 1,000 hours of operation treating flue gas at NCCC. The Polaris™ membranes used on this system demonstrated stable performance, and when combined with over 10,000 hours of operation at NCCC on a 1 TPD system, the risk associated with uncertainty in the durability of postcombustion capture membranes has been greatly reduced. Moreover, next-generation Polaris membranes with higher performance and lower cost were validation tested on the 1 TPD system. The 20 TPD system also demonstrated successful operation of a new low-pressure-drop sweep module that will reduce parasitic energy losses at full scale by as much as 10 MWe. In modeling and pilot boiler testing, B&W confirmed the viability of CO 2 recycle to the boiler as envisioned in the MTR process design. The impact of this CO 2 recycle on boiler efficiency was quantified and incorporated into a TEA of the membrane capture process applied to a full-scale power plant. As with previous studies, the TEA showed the membrane process to be lower cost than the conventional solvent capture process even at 90% CO 2capture. A sensitivity study indicates that the membrane capture cost decreases significantly if the 90% capture requirement is relaxed. Depending on the process design, a minimum capture cost is achieved at 30-60% capture, values that would meet proposed CO 2 emission regulations for coal-fired power plants. In summary, this project has successfully advanced the MTR membrane capture process through small pilot testing (technology readiness level 6). The technology is ready for future scale-up to the 10 MWe size.« less

Effective Elastic and Neutron Capture Cross Section Calculations Corresponding to Simulated Fluid Properties from CO2 Push-Pull Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chugunov, Nikita; Altundas, Bilgin

The submission contains a .xls files consisting of 10 excel sheets, which contain combined list of pressure, saturation, salinity, temperature profiles from the simulation of CO2 push-pull using Brady reservoir model and the corresponding effective compressional and shear velocity, bulk density, and fluid and time-lapse neutron capture cross section profiles of rock at times 0 day (baseline) through 14 days. First 9 sheets (each named after the corresponding CO2 push-pull simulation time) contains simulated pressure, saturation, temperature, salinity profiles and the corresponding effective elastic and neutron capture cross section profiles of rock matrix at the time of CO2 injection. Eachmore » sheet contains two sets of effective compressional velocity profiles of the rock, one based on Gassmann and the other based on Patchy saturation model. Effective neutron capture cross section calculations are done using a proprietary neutron cross-section simulator (SNUPAR) whereas for the thermodynamic properties of CO2 and bulk density of rock matrix filled with fluid, a standalone fluid substitution tool by Schlumberger is used. Last sheet in the file contains the bulk modulus of solid rock, which is inverted from the rock properties (porosity, sound speed etc) based on Gassmann model. Bulk modulus of solid rock in turn is used in the fluid substitution.« less

Rapid Design and Testing of Novel Gas/liquid Contacting Devices for Post-Combustion CO 2 Capture via 3D Printing - Phase II Final Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Panaccione, Charles; Staab, Greg; Meuleman, Erik

ION has developed a mathematically driven model for a contacting device incorporating mass transfer, heat transfer, and computational fluid dynamics. This model is based upon a parametric structure for purposes of future commercialization. The most promising design from modeling was 3D printed and tested in a bench scale CO 2 capture unit and compared to commercially available structured packing tested in the same unit.

Predicting mixed-gas adsorption equilibria on activated carbon for precombustion CO2 capture.

PubMed

García, S; Pis, J J; Rubiera, F; Pevida, C

2013-05-21

We present experimentally measured adsorption isotherms of CO2, H2, and N2 on a phenol-formaldehyde resin-based activated carbon, which had been previously synthesized for the separation of CO2 in a precombustion capture process. The single component adsorption isotherms were measured in a magnetic suspension balance at three different temperatures (298, 318, and 338 K) and over a large range of pressures (from 0 to 3000-4000 kPa). These values cover the temperature and pressure conditions likely to be found in a precombustion capture scenario, where CO2 needs to be separated from a CO2/H2/N2 gas stream at high pressure (~1000-1500 kPa) and with a high CO2 concentration (~20-40 vol %). Data on the pure component isotherms were correlated using the Langmuir, Sips, and dual-site Langmuir (DSL) models, i.e., a two-, three-, and four-parameter model, respectively. By using the pure component isotherm fitting parameters, adsorption equilibrium was then predicted for multicomponent gas mixtures by the extended models. The DSL model was formulated considering the energetic site-matching concept, recently addressed in the literature. Experimental gas-mixture adsorption equilibrium data were calculated from breakthrough experiments conducted in a lab-scale fixed-bed reactor and compared with the predictions from the models. Breakthrough experiments were carried out at a temperature of 318 K and five different pressures (300, 500, 1000, 1500, and 2000 kPa) where two different CO2/H2/N2 gas mixtures were used as the feed gas in the adsorption step. The DSL model was found to be the one that most accurately predicted the CO2 adsorption equilibrium in the multicomponent mixture. The results presented in this work highlight the importance of performing experimental measurements of mixture adsorption equilibria, as they are of utmost importance to discriminate between models and to correctly select the one that most closely reflects the actual process.

Techno-Economic Analysis of a Secondary Air Stripper Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heberle, J.R.; Nikolic, Heather; Thompson, Jesse

We present results of an initial techno-economic assessment on a post-combustion CO2 capture process developed by the Center for Applied Energy Research (CAER) at the University of Kentucky using Mitsubishi Hitachi Power Systems’ H3-1 aqueous amine solvent. The analysis is based on data collected at a 0.7 MWe pilot unit combined with laboratory data and process simulations. The process adds a secondary air stripper to a conventional solvent process, which increases the cyclic loading of the solvent in two ways. First, air strips additional CO2 from the solvent downstream of the conventional steam-heated thermal stripper. This extra stripping of CO2more » reduces the lean loading entering the absorber. Second, the CO2-enriched air is then sent to the boiler for use as secondary air. This recycling of CO2 results in a higher concentration of CO2 in the flue gas sent to the absorber, and hence a higher rich loading of the solvent exiting the absorber. A process model was incorporated into a full-scale supercritical pulverized coal power plant model to determine the plant performance and heat and mass balances. The performance and heat and mass balance data were used to size equipment and develop cost estimates for capital and operating costs. Lifecycle costs were considered through a levelized cost of electricity (LCOE) assessment based on the capital cost estimate and modeled performance. The results of the simulations show that the CAER process yields a regeneration energy of 3.12 GJ/t CO2, a $53.05/t CO2 capture cost, and LCOE of $174.59/MWh. This compares to the U.S. Department of Energy’s projected costs (Case 10) of regeneration energy of 3.58 GJ/t CO2 , a $61.31/t CO2 capture cost, and LCOE of $189.59/MWh. For H3-1, the CAER process results in a regeneration energy of 2.62 GJ/tCO2 with a stripper pressure of 5.2 bar, a capture cost of $46.93/t CO2, and an LCOE of $164.33/MWh.« less

Dynamic modeling and control of a solid-sorbent CO{sub 2} capture process with two-stage bubbling fluidized bed adsorber reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Modekurti, S.; Bhattacharyya, D.; Zitney, S.

2012-01-01

Solid-sorbent-based CO{sub 2} capture processes have strong potential for reducing the overall energy penalty for post-combustion capture from the flue gas of a conventional pulverized coal power plant. However, the commercial success of this technology is contingent upon it operating over a wide range of capture rates, transient events, malfunctions, and disturbances, as well as under uncertainties. To study these operational aspects, a dynamic model of a solid-sorbent-based CO{sub 2} capture process has been developed. In this work, a one-dimensional (1D), non-isothermal, dynamic model of a two-stage bubbling fluidized bed (BFB) adsorber-reactor system with overflow-type weir configuration has been developedmore » in Aspen Custom Modeler (ACM). The physical and chemical properties of the sorbent used in this study are based on a sorbent (32D) developed at National Energy Technology Laboratory (NETL). Each BFB is divided into bubble, emulsion, and cloud-wake regions with the assumptions that the bubble region is free of solids while both gas and solid phases coexist in the emulsion and cloud-wake regions. The BFB dynamic model includes 1D partial differential equations (PDEs) for mass and energy balances, along with comprehensive reaction kinetics. In addition to the two BFB models, the adsorber-reactor system includes 1D PDE-based dynamic models of the downcomer and outlet hopper, as well as models of distributors, control valves, and other pressure-drop devices. Consistent boundary and initial conditions are considered for simulating the dynamic model. Equipment items are sized and appropriate heat transfer options, wherever needed, are provided. Finally, a valid pressure-flow network is developed and a lower-level control system is designed. Using ACM, the transient responses of various process variables such as flue gas and sorbent temperatures, overall CO{sub 2} capture, level of solids in the downcomer and hopper have been studied by simulating typical disturbances such as change in the temperature, flowrate, and composition of the flue gas. To maintain the overall CO{sub 2} capture at a desired level in face of the typical disturbances, two control strategies were considered–a proportional-integral-derivative (PID)-based feedback control strategy and a feedforward-augmented feedback control strategy. Dynamic simulation results show that both the strategies result in unacceptable overshoot/undershoot and a long settling time. To improve the control system performance, a linear model predictive controller (LMPC) is designed. In summary, the overall results illustrate how optimizing the operation and control of carbon capture systems can have a significant impact on the extent and the rate at which commercial-scale capture processes will be scaled-up, deployed, and used in the years to come.« less

Electricity from fossil fuels without CO2 emissions: assessing the costs of carbon dioxide capture and sequestration in U.S. electricity markets.

PubMed

Johnson, T L; Keith, D W

2001-10-01

The decoupling of fossil-fueled electricity production from atmospheric CO2 emissions via CO2 capture and sequestration (CCS) is increasingly regarded as an important means of mitigating climate change at a reasonable cost. Engineering analyses of CO2 mitigation typically compare the cost of electricity for a base generation technology to that for a similar plant with CO2 capture and then compute the carbon emissions mitigated per unit of cost. It can be hard to interpret mitigation cost estimates from this plant-level approach when a consistent base technology cannot be identified. In addition, neither engineering analyses nor general equilibrium models can capture the economics of plant dispatch. A realistic assessment of the costs of carbon sequestration as an emissions abatement strategy in the electric sector therefore requires a systems-level analysis. We discuss various frameworks for computing mitigation costs and introduce a simplified model of electric sector planning. Results from a "bottom-up" engineering-economic analysis for a representative U.S. North American Electric Reliability Council (NERC) region illustrate how the penetration of CCS technologies and the dispatch of generating units vary with the price of carbon emissions and thereby determine the relationship between mitigation cost and emissions reduction.

Electricity from Fossil Fuels without CO2 Emissions: Assessing the Costs of Carbon Dioxide Capture and Sequestration in U.S. Electricity Markets.

PubMed

Johnson, Timothy L; Keith, David W

2001-10-01

The decoupling of fossil-fueled electricity production from atmospheric CO 2 emissions via CO 2 capture and sequestration (CCS) is increasingly regarded as an important means of mitigating climate change at a reasonable cost. Engineering analyses of CO 2 mitigation typically compare the cost of electricity for a base generation technology to that for a similar plant with CO 2 capture and then compute the carbon emissions mitigated per unit of cost. It can be hard to interpret mitigation cost estimates from this plant-level approach when a consistent base technology cannot be identified. In addition, neither engineering analyses nor general equilibrium models can capture the economics of plant dispatch. A realistic assessment of the costs of carbon sequestration as an emissions abatement strategy in the electric sector therefore requires a systems-level analysis. We discuss various frameworks for computing mitigation costs and introduce a simplified model of electric sector planning. Results from a "bottom-up" engineering-economic analysis for a representative U.S. North American Electric Reliability Council (NERC) region illustrate how the penetration of CCS technologies and the dispatch of generating units vary with the price of carbon emissions and thereby determine the relationship between mitigation cost and emissions reduction.

High throughput screening of CO2 solubility in aqueous monoamine solutions.

PubMed

Porcheron, Fabien; Gibert, Alexandre; Mougin, Pascal; Wender, Aurélie

2011-03-15

Post-combustion Carbon Capture and Storage technology (CCS) is viewed as an efficient solution to reduce CO(2) emissions of coal-fired power stations. In CCS, an aqueous amine solution is commonly used as a solvent to selectively capture CO(2) from the flue gas. However, this process generates additional costs, mostly from the reboiler heat duty required to release the carbon dioxide from the loaded solvent solution. In this work, we present thermodynamic results of CO(2) solubility in aqueous amine solutions from a 6-reactor High Throughput Screening (HTS) experimental device. This device is fully automated and designed to perform sequential injections of CO(2) within stirred-cell reactors containing the solvent solutions. The gas pressure within each reactor is monitored as a function of time, and the resulting transient pressure curves are transformed into CO(2) absorption isotherms. Solubility measurements are first performed on monoethanolamine, diethanolamine, and methyldiethanolamine aqueous solutions at T = 313.15 K. Experimental results are compared with existing data in the literature to validate the HTS device. In addition, a comprehensive thermodynamic model is used to represent CO(2) solubility variations in different classes of amine structures upon a wide range of thermodynamic conditions. This model is used to fit the experimental data and to calculate the cyclic capacity, which is a key parameter for CO(2) process design. Solubility measurements are then performed on a set of 50 monoamines and cyclic capacities are extracted using the thermodynamic model, to asses the potential of these molecules for CO(2) capture.

Carbon dioxide capture using covalent organic frameworks (COFs) type material-a theoretical investigation.

PubMed

Dash, Bibek

2018-04-26

The present work deals with a density functional theory (DFT) study of porous organic framework materials containing - groups for CO 2 capture. In this study, first principle calculations were performed for CO 2 adsorption using N-containing covalent organic framework (COFs) models. Ab initio and DFT-based methods were used to characterize the N-containing porous model system based on their interaction energies upon complexing with CO 2 and nitrogen gas. Binding energies (BEs) of CO 2 and N 2 molecules with the polymer framework were calculated with DFT methods. Hybrid B3LYP and second order MP2 methods combined with of Pople 6-31G(d,p) and correlation consistent basis sets cc-pVDZ, cc-pVTZ and aug-ccVDZ were used to calculate BEs. The effect of linker groups in the designed covalent organic framework model system on the CO 2 and N 2 interactions was studied using quantum calculations.

CO2 Capture by Injection of Flue Gas or CO2-N2 Mixtures into Hydrate Reservoirs: Dependence of CO2 Capture Efficiency on Gas Hydrate Reservoir Conditions.

PubMed

Hassanpouryouzband, Aliakbar; Yang, Jinhai; Tohidi, Bahman; Chuvilin, Evgeny; Istomin, Vladimir; Bukhanov, Boris; Cheremisin, Alexey

2018-04-03

Injection of flue gas or CO 2 -N 2 mixtures into gas hydrate reservoirs has been considered as a promising option for geological storage of CO 2 . However, the thermodynamic process in which the CO 2 present in flue gas or a CO 2 -N 2 mixture is captured as hydrate has not been well understood. In this work, a series of experiments were conducted to investigate the dependence of CO 2 capture efficiency on reservoir conditions. The CO 2 capture efficiency was investigated at different injection pressures from 2.6 to 23.8 MPa and hydrate reservoir temperatures from 273.2 to 283.2 K in the presence of two different saturations of methane hydrate. The results showed that more than 60% of the CO 2 in the flue gas was captured and stored as CO 2 hydrate or CO 2 -mixed hydrates, while methane-rich gas was produced. The efficiency of CO 2 capture depends on the reservoir conditions including temperature, pressure, and hydrate saturation. For a certain reservoir temperature, there is an optimum reservoir pressure at which the maximum amount of CO 2 can be captured from the injected flue gas or CO 2 -N 2 mixtures. This finding suggests that it is essential to control the injection pressure to enhance CO 2 capture efficiency by flue gas or CO 2 -N 2 mixtures injection.

System-level modeling for geological storage of CO2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yingqi; Oldenburg, Curtis M.; Finsterle, Stefan

2006-04-24

One way to reduce the effects of anthropogenic greenhousegases on climate is to inject carbon dioxide (CO2) from industrialsources into deep geological formations such as brine formations ordepleted oil or gas reservoirs. Research has and is being conducted toimprove understanding of factors affecting particular aspects ofgeological CO2 storage, such as performance, capacity, and health, safetyand environmental (HSE) issues, as well as to lower the cost of CO2capture and related processes. However, there has been less emphasis todate on system-level analyses of geological CO2 storage that considergeological, economic, and environmental issues by linking detailedrepresentations of engineering components and associated economic models.Themore » objective of this study is to develop a system-level model forgeological CO2 storage, including CO2 capture and separation,compression, pipeline transportation to the storage site, and CO2injection. Within our system model we are incorporating detailedreservoir simulations of CO2 injection and potential leakage withassociated HSE effects. The platform of the system-level modelingisGoldSim [GoldSim, 2006]. The application of the system model is focusedon evaluating the feasibility of carbon sequestration with enhanced gasrecovery (CSEGR) in the Rio Vista region of California. The reservoirsimulations are performed using a special module of the TOUGH2 simulator,EOS7C, for multicomponent gas mixtures of methane and CO2 or methane andnitrogen. Using this approach, the economic benefits of enhanced gasrecovery can be directly weighed against the costs, risks, and benefitsof CO2 injection.« less

Borophene as a Promising Material for Charge-Modulated Switchable CO2 Capture.

PubMed

Tan, Xin; Tahini, Hassan A; Smith, Sean C

2017-06-14

Ideal carbon dioxide (CO 2 ) capture materials for practical applications should bind CO 2 molecules neither too weakly to limit good loading kinetics nor too strongly to limit facile release. Although charge-modulated switchable CO 2 capture has been proposed to be a controllable, highly selective, and reversible CO 2 capture strategy, the development of a practical gas-adsorbent material remains a great challenge. In this study, by means of density functional theory (DFT) calculations, we have examined the possibility of conductive borophene nanosheets as promising sorbent materials for charge-modulated switchable CO 2 capture. Our results reveal that the binding strength of CO 2 molecules on negatively charged borophene can be significantly enhanced by injecting extra electrons into the adsorbent. At saturation CO 2 capture coverage, the negatively charged borophene achieves CO 2 capture capacities up to 6.73 × 10 14 cm -2 . In contrast to the other CO 2 capture methods, the CO 2 capture/release processes on negatively charged borophene are reversible with fast kinetics and can be easily controlled via switching on/off the charges carried by borophene nanosheets. Moreover, these negatively charged borophene nanosheets are highly selective for separating CO 2 from mixtures with CH 4 , H 2 , and/or N 2 . This theoretical exploration will provide helpful guidance for identifying experimentally feasible, controllable, highly selective, and high-capacity CO 2 capture materials with ideal thermodynamics and reversibility.

Microwave-assisted nitric acid treatment of sepiolite and functionalization with polyethylenimine applied to CO2 capture and CO2/N2 separation

NASA Astrophysics Data System (ADS)

Vilarrasa-García, E.; Cecilia, J. A.; Bastos-Neto, M.; Cavalcante, C. L.; Azevedo, D. C. S.; Rodríguez-Castellón, E.

2017-07-01

Sepiolite was treated in HNO3 solutions with the assistance of microwave radiation. This treatment caused the progressive depletion of Mg2+, the gradual degradation of the sepiolite structure and the formation of an amorphous silica phase, which contributes to a noticeable increase of the surface area. The use of microwaves during acid treatment, after few minutes, led to materials with similar SBET to those obtained after 48 h with conventional heating methods. The influence of mineralogical impurities, crystallinity and chemical composition in the reactivity of sepiolite to this treatment was also studied. The obtained materials were impregnated with polyethylenimine and assessed for CO2 capture and CO2/N2 selectivity at different temperatures. Experimental equilibrium data were fitted to Langmuir and Sips models. The adsorption data revealed that sepiolite can be an interesting adsorbent for CO2 capture, achieving a capacity of 1.70 mmol g-1 at 338 K and 1 bar, providing a high CO2/N2 selectivity (440 mol CO2/mol N2).

CO 2 Leakage Into Shallow Aquifers: Modeling CO 2 Gas Evolution and Accumulation at Interfaces of Heterogeneity

DOE PAGES

Porter, Mark L.; Plampin, Michael; Pawar, Rajesh; ...

2014-12-31

The physicochemical processes associated with CO 2 leakage into shallow aquifer systems are complex and span multiple spatial and time scales. Continuum-scale numerical models that faithfully represent the underlying pore-scale physics are required to predict the long-term behavior and aid in risk analysis regarding regulatory and management decisions. This study focuses on benchmarking the numerical simulator, FEHM, with intermediate-scale column experiments of CO 2 gas evolution in homogeneous and heterogeneous sand configurations. Inverse modeling was conducted to calibrate model parameters and determine model sensitivity to the observed steady-state saturation profiles. It is shown that FEHM is a powerful tool thatmore » is capable of capturing the experimentally observed out ow rates and saturation profiles. Moreover, FEHM captures the transition from single- to multi-phase flow and CO 2 gas accumulation at interfaces separating sands. We also derive a simple expression, based on Darcy's law, for the pressure at which CO 2 free phase gas is observed and show that it reliably predicts the location at which single-phase flow transitions to multi-phase flow.« less

Bench-Scale Testing and Process Performance Projections of CO2 Capture by CO2–Binding Organic Liquids (CO2BOLs) With and Without Polarity-Swing-Assisted Regeneration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Feng; Heldebrant, David J.; Mathias, Paul M.

This manuscript provides a detailed analysis of a continuous flow, bench scale study of the CO2BOL solvent platform with and without its Polarity Swing Assisted Regeneration (PSAR). This study encompassed four months of continuous flow testing of a candidate CO2BOL with a thermal regeneration and PSAR regeneration using decane antisolvent. In both regeneration schemes, steady state capture of >90 %CO2 was achieved using simulated flue gas at acceptable L/G ratios. Aspen Plus™ modeling was performed to assess process performance compared to previous equilibrium performance projections. This paper also includes net power projections, and comparisons to DOE’s Case 10 amine baseline.

Advanced Amine Solvent Formulations and Process Integration for Near-Term CO2 Capture Success

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisher, Kevin S.; Searcy, Katherine; Rochelle, Gary T.

2007-06-28

This Phase I SBIR project investigated the economic and technical feasibility of advanced amine scrubbing systems for post-combustion CO2 capture at coal-fired power plants. Numerous combinations of advanced solvent formulations and process configurations were screened for energy requirements, and three cases were selected for detailed analysis: a monoethanolamine (MEA) base case and two “advanced” cases: an MEA/Piperazine (PZ) case, and a methyldiethanolamine (MDEA) / PZ case. The MEA/PZ and MDEA/PZ cases employed an advanced “double matrix” stripper configuration. The basis for calculations was a model plant with a gross capacity of 500 MWe. Results indicated that CO2 capture increased themore » base cost of electricity from 5 cents/kWh to 10.7 c/kWh for the MEA base case, 10.1 c/kWh for the MEA / PZ double matrix, and 9.7 c/kWh for the MDEA / PZ double matrix. The corresponding cost per metric tonne CO2 avoided was 67.20 $/tonne CO2, 60.19 $/tonne CO2, and 55.05 $/tonne CO2, respectively. Derated capacities, including base plant auxiliary load of 29 MWe, were 339 MWe for the base case, 356 MWe for the MEA/PZ double matrix, and 378 MWe for the MDEA / PZ double matrix. When compared to the base case, systems employing advanced solvent formulations and process configurations were estimated to reduce reboiler steam requirements by 20 to 44%, to reduce derating due to CO2 capture by 13 to 30%, and to reduce the cost of CO2 avoided by 10 to 18%. These results demonstrate the potential for significant improvements in the overall economics of CO2 capture via advanced solvent formulations and process configurations.« less

Using infrastructure optimization to reduce greenhouse gas emissions from oil sands extraction and processing.

PubMed

Middleton, Richard S; Brandt, Adam R

2013-02-05

The Alberta oil sands are a significant source of oil production and greenhouse gas emissions, and their importance will grow as the region is poised for decades of growth. We present an integrated framework that simultaneously considers economic and engineering decisions for the capture, transport, and storage of oil sands CO(2) emissions. The model optimizes CO(2) management infrastructure at a variety of carbon prices for the oil sands industry. Our study reveals several key findings. We find that the oil sands industry lends itself well to development of CO(2) trunk lines due to geographic coincidence of sources and sinks. This reduces the relative importance of transport costs compared to nonintegrated transport systems. Also, the amount of managed oil sands CO(2) emissions, and therefore the CCS infrastructure, is very sensitive to the carbon price; significant capture and storage occurs only above 110$/tonne CO(2) in our simulations. Deployment of infrastructure is also sensitive to CO(2) capture decisions and technology, particularly the fraction of capturable CO(2) from oil sands upgrading and steam generation facilities. The framework will help stakeholders and policy makers understand how CCS infrastructure, including an extensive pipeline system, can be safely and cost-effectively deployed.

System-level modeling for economic evaluation of geological CO2storage in gas reservoirs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yingqi; Oldenburg, Curtis M.; Finsterle, Stefan

2006-03-02

One way to reduce the effects of anthropogenic greenhousegases on climate is to inject carbon dioxide (CO2) from industrialsources into deep geological formations such as brine aquifers ordepleted oil or gas reservoirs. Research is being conducted to improveunderstanding of factors affecting particular aspects of geological CO2storage (such as storage performance, storage capacity, and health,safety and environmental (HSE) issues) as well as to lower the cost ofCO2 capture and related processes. However, there has been less emphasisto date on system-level analyses of geological CO2 storage that considergeological, economic, and environmental issues by linking detailedprocess models to representations of engineering components andassociatedmore » economic models. The objective of this study is to develop asystem-level model for geological CO2 storage, including CO2 capture andseparation, compression, pipeline transportation to the storage site, andCO2 injection. Within our system model we are incorporating detailedreservoir simulations of CO2 injection into a gas reservoir and relatedenhanced production of methane. Potential leakage and associatedenvironmental impacts are also considered. The platform for thesystem-level model is GoldSim [GoldSim User's Guide. GoldSim TechnologyGroup; 2006, http://www.goldsim.com]. The application of the system modelfocuses on evaluating the feasibility of carbon sequestration withenhanced gas recovery (CSEGR) in the Rio Vista region of California. Thereservoir simulations are performed using a special module of the TOUGH2simulator, EOS7C, for multicomponent gas mixtures of methane and CO2.Using a system-level modeling approach, the economic benefits of enhancedgas recovery can be directly weighed against the costs and benefits ofCO2 injection.« less

Bench-Scale Process for Low-Cost Carbon Dioxide (CO2) Capture Using a Phase-Changing Absorbent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westendorf, Tiffany; Caraher, Joel; Chen, Wei

2015-03-31

The objective of this project is to design and build a bench-scale process for a novel phase-changing aminosilicone-based CO2-capture solvent. The project will establish scalability and technical and economic feasibility of using a phase-changing CO2-capture absorbent for post-combustion capture of CO2 from coal-fired power plants with 90% capture efficiency and 95% CO2 purity at a cost of $40/tonne of CO2 captured by 2025 and a cost of <$10/tonne of CO2 captured by 2035. In the first budget period of this project, the bench-scale phase-changing CO2 capture process was designed using data and operating experience generated under a previous project (ARPA-emore » project DE-AR0000084). Sizing and specification of all major unit operations was completed, including detailed process and instrumentation diagrams. The system was designed to operate over a wide range of operating conditions to allow for exploration of the effect of process variables on CO2 capture performance.« less

High-throughput screening of metal-porphyrin-like graphenes for selective capture of carbon dioxide

PubMed Central

Bae, Hyeonhu; Park, Minwoo; Jang, Byungryul; Kang, Yura; Park, Jinwoo; Lee, Hosik; Chung, Haegeun; Chung, ChiHye; Hong, Suklyun; Kwon, Yongkyung; Yakobson, Boris I.; Lee, Hoonkyung

2016-01-01

Nanostructured materials, such as zeolites and metal-organic frameworks, have been considered to capture CO2. However, their application has been limited largely because they exhibit poor selectivity for flue gases and low capture capacity under low pressures. We perform a high-throughput screening for selective CO2 capture from flue gases by using first principles thermodynamics. We find that elements with empty d orbitals selectively attract CO2 from gaseous mixtures under low CO2 pressures (~10−3 bar) at 300 K and release it at ~450 K. CO2 binding to elements involves hybridization of the metal d orbitals with the CO2 π orbitals and CO2-transition metal complexes were observed in experiments. This result allows us to perform high-throughput screening to discover novel promising CO2 capture materials with empty d orbitals (e.g., Sc– or V–porphyrin-like graphene) and predict their capture performance under various conditions. Moreover, these findings provide physical insights into selective CO2 capture and open a new path to explore CO2 capture materials. PMID:26902156

High-throughput screening of metal-porphyrin-like graphenes for selective capture of carbon dioxide.

PubMed

Bae, Hyeonhu; Park, Minwoo; Jang, Byungryul; Kang, Yura; Park, Jinwoo; Lee, Hosik; Chung, Haegeun; Chung, ChiHye; Hong, Suklyun; Kwon, Yongkyung; Yakobson, Boris I; Lee, Hoonkyung

2016-02-23

Nanostructured materials, such as zeolites and metal-organic frameworks, have been considered to capture CO2. However, their application has been limited largely because they exhibit poor selectivity for flue gases and low capture capacity under low pressures. We perform a high-throughput screening for selective CO2 capture from flue gases by using first principles thermodynamics. We find that elements with empty d orbitals selectively attract CO2 from gaseous mixtures under low CO2 pressures (~10(-3) bar) at 300 K and release it at ~450 K. CO2 binding to elements involves hybridization of the metal d orbitals with the CO2 π orbitals and CO2-transition metal complexes were observed in experiments. This result allows us to perform high-throughput screening to discover novel promising CO2 capture materials with empty d orbitals (e.g., Sc- or V-porphyrin-like graphene) and predict their capture performance under various conditions. Moreover, these findings provide physical insights into selective CO2 capture and open a new path to explore CO2 capture materials.

High-throughput screening of metal-porphyrin-like graphenes for selective capture of carbon dioxide

NASA Astrophysics Data System (ADS)

Bae, Hyeonhu; Park, Minwoo; Jang, Byungryul; Kang, Yura; Park, Jinwoo; Lee, Hosik; Chung, Haegeun; Chung, Chihye; Hong, Suklyun; Kwon, Yongkyung; Yakobson, Boris I.; Lee, Hoonkyung

2016-02-01

Nanostructured materials, such as zeolites and metal-organic frameworks, have been considered to capture CO2. However, their application has been limited largely because they exhibit poor selectivity for flue gases and low capture capacity under low pressures. We perform a high-throughput screening for selective CO2 capture from flue gases by using first principles thermodynamics. We find that elements with empty d orbitals selectively attract CO2 from gaseous mixtures under low CO2 pressures (~10-3 bar) at 300 K and release it at ~450 K. CO2 binding to elements involves hybridization of the metal d orbitals with the CO2 π orbitals and CO2-transition metal complexes were observed in experiments. This result allows us to perform high-throughput screening to discover novel promising CO2 capture materials with empty d orbitals (e.g., Sc- or V-porphyrin-like graphene) and predict their capture performance under various conditions. Moreover, these findings provide physical insights into selective CO2 capture and open a new path to explore CO2 capture materials.

Effects of heat exchanger tubes on hydrodynamics and CO 2 capture of a sorbent-based fluidized bed reactor

DOE PAGES

Lai, Canhai; Xu, Zhijie; Li, Tingwen; ...

2017-08-05

In virtual design and scale up of pilot-scale carbon capture systems, the coupled reactive multiphase flow problem must be solved to predict the adsorber's performance and capture efficiency under various operation conditions. This paper focuses on the detailed computational fluid dynamics (CFD) modeling of a pilot-scale fluidized bed adsorber equipped with vertical cooling tubes. Multiphase Flow with Interphase eXchanges (MFiX), an open-source multiphase flow CFD solver, is used for the simulations with custom code to simulate the chemical reactions and filtered sub-grid models to capture the effect of the unresolved details in the coarser mesh for simulations with reasonable accuracymore » and manageable computational effort. Previously developed filtered models for horizontal cylinder drag, heat transfer, and reaction kinetics have been modified to derive the 2D filtered models representing vertical cylinders in the coarse-grid CFD simulations. The effects of the heat exchanger configurations (i.e., horizontal or vertical tubes) on the adsorber's hydrodynamics and CO 2 capture performance are then examined. A one-dimensional three-region process model is briefly introduced for comparison purpose. The CFD model matches reasonably well with the process model while provides additional information about the flow field that is not available with the process model.« less

Reinventing Design Principles for Developing Low-Viscosity Carbon Dioxide-Binding Organic Liquids for Flue Gas Clean Up.

PubMed

Malhotra, Deepika; Koech, Phillip K; Heldebrant, David J; Cantu, David C; Zheng, Feng; Glezakou, Vassiliki-Alexandra; Rousseau, Roger

2017-02-08

Anthropogenic CO 2 emissions from point sources (e.g., coal fired-power plants) account for the majority of the greenhouse gases in the atmosphere. Water-lean solvent systems such as CO 2 -binding organic liquids (CO 2 BOLs) are being developed to reduce the energy requirement for CO 2 capture. Many water-lean solvents such as CO 2 BOLs are currently limited by the high viscosities of concentrated electrolyte solvents, thus many of these solvents have yet to move toward commercialization. Conventional standard trial-and-error approaches for viscosity reduction, while effective, are time consuming and economically expensive. We rethink the metrics and design principles of low-viscosity CO 2 -capture solvents using a combined synthesis and computational modeling approach. We critically study the effects of viscosity reducing factors such as orientation of hydrogen bonding, introduction of higher degrees of freedom, and cation or anion charge solvation, and assess whether or how each factor affects viscosity of CO 2 BOL CO 2 capture solvents. Ultimately, we found that hydrogen bond orientation and strength is the predominant factor influencing the viscosity in CO 2 BOL solvents. With this knowledge, a new CO 2 BOL variant, 1-MEIPADM-2-BOL, was synthesized and tested, resulting in a solvent that is approximately 60 % less viscous at 25 mol % CO 2 loading than our base compound 1-IPADM-2-BOL. The insights gained from the current study redefine the fundamental concepts and understanding of what influences viscosity in concentrated organic CO 2 -capture solvents. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Molecular simulation study of the competitive adsorption of H2O and CO2 in zeolite 13X.

PubMed

Joos, Lennart; Swisher, Joseph A; Smit, Berend

2013-12-23

The presence of H2O in postcombustion gas streams is an important technical issue for deploying CO2-selective adsorbents. Because of its permanent dipole, H2O can interact strongly with materials where the selectivity for CO2 is a consequence of its quadrupole interacting with charges in the material. We performed molecular simulations to model the adsorption of pure H2O and CO2 as well as H2O/CO2 mixtures in 13X, a popular zeolite for CO2 capture processes that is commercially available. The simulations show that H2O reduces the capacity of these materials for adsorbing CO2 by an order of magnitude and that at the partial pressures of H2O relevant for postcombustion capture, 13X will be essentially saturated with H2O .

The Concept and Analytical Investigation of CO2 and Steam Co-Electrolysis for Resource Utilization in Space Exploration

NASA Technical Reports Server (NTRS)

McKellar, Michael G.; Stoots, Carl M.; Sohal, Manohar S.; Mulloth, Lila M.; Luna, Bernadette; Abney, Morgan B.

2010-01-01

CO2 acquisition and utilization technologies will have a vital role in designing sustainable and affordable life support and in situ fuel production architectures for human and robotic exploration of Moon and Mars. For long-term human exploration to be practical, reliable technologies have to be implemented to capture the metabolic CO2 from the cabin air and chemically reduce it to recover oxygen. Technologies that enable the in situ capture and conversion of atmospheric CO2 to fuel are essential for a viable human mission to Mars. This paper describes the concept and mathematical analysis of a closed-loop life support system based on combined electrolysis of CO2 and steam (co-electrolysis). Products of the coelectrolysis process include oxygen and syngas (CO and H2) that are suitable for life support and synthetic fuel production, respectively. The model was developed based on the performance of a co-electrolysis system developed at Idaho National Laboratory (INL). Individual and combined process models of the co-electrolysis and Sabatier, Bosch, Boudouard, and hydrogenation reactions are discussed and their performance analyses in terms of oxygen production and CO2 utilization are presented.

Selective gas capture via kinetic trapping

DOE PAGES

Kundu, Joyjit; Pascal, Tod; Prendergast, David; ...

2016-07-13

Conventional approaches to the capture of CO 2 by metal-organic frameworks focus on equilibrium conditions, and frameworks that contain little CO 2 in equilibrium are often rejected as carbon-capture materials. Here we use a statistical mechanical model, parameterized by quantum mechanical data, to suggest that metal-organic frameworks can be used to separate CO 2 from a typical flue gas mixture when used under nonequilibrium conditions. The origin of this selectivity is an emergent gas-separation mechanism that results from the acquisition by different gas types of different mobilities within a crowded framework. The resulting distribution of gas types within the frameworkmore » is in general spatially and dynamically heterogeneous. Our results suggest that relaxing the requirement of equilibrium can substantially increase the parameter space of conditions and materials for which selective gas capture can be effected.« less

Electrochemical capture and release of carbon dioxide

DOE PAGES

Rheinhardt, Joseph H.; Singh, Poonam; Tarakeshwar, Pilarisetty; ...

2017-01-18

Understanding the chemistry of carbon dioxide is key to affecting changes in atmospheric concentrations. One area of intense interest is CO 2 capture in chemically reversible cycles relevant to carbon capture technologies. Most CO 2 capture methods involve thermal cycles in which a nucleophilic agent captures CO 2 from impure gas streams (e.g., flue gas), followed by a thermal process in which pure CO 2 is released. Several reviews have detailed progress in these approaches. A less explored strategy uses electrochemical cycles to capture CO 2 and release it in pure form. These cycles typically rely on electrochemical generation ofmore » nucleophiles that attack CO 2 at the electrophilic carbon atom, forming a CO 2 adduct. Then, CO 2 is released in pure form via a subsequent electrochemical step. In this Perspective, we describe electrochemical cycles for CO 2 capture and release, emphasizing electrogenerated nucleophiles. As a result, we also discuss some advantages and disadvantages inherent in this general approach.« less

Carbon dioxide (hydrogen sulfide) membrane separations and WGS membrane reactor modeling for fuel cells

NASA Astrophysics Data System (ADS)

Huang, Jin

Acid-gas removal is of great importance in many environmental or energy-related processes. Compared to current commercial technologies, membrane-based CO2 and H2S capture has the advantages of low energy consumption, low weight and space requirement, simplicity of installation/operation, and high process flexibility. However, the large-scale application of the membrane separation technology is limited by the relatively low transport properties. In this study, CO2 (H2S)-selective polymeric membranes with high permeability and high selectivity have been studied based on the facilitated transport mechanism. The membrane showed facilitated effect for both CO2 and H2S. A CO2 permeability of above 2000 Barrers, a CO2/H2 selectivity of greater than 40, and a CO2/N2 selectivity of greater than 200 at 100--150°C were observed. As a result of higher reaction rate and smaller diffusing compound, the H2S permeability and H2S/H2 selectivity were about three times higher than those properties for CO2. The novel CO2-selective membrane has been applied to capture CO 2 from flue gas and natural gas. In the CO2 capture experiments from a gas mixture with N2 and H2, a permeate CO 2 dry concentration of greater than 98% was obtained by using steam as the sweep gas. In CO2/CH4 separation, decent CO 2 transport properties were obtained with a feed pressure up to 500 psia. With the thin-film composite membrane structure, significant increase on the CO2 flux was achieved with the decrease of the selective layer thickness. With the continuous removal of CO2, CO2-selective water-gas-shift (WGS) membrane reactor is a promising approach to enhance CO conversion and increase the purity of H2 at process pressure under relatively low temperature. The simultaneous reaction and transport process in the countercurrent WGS membrane reactor was simulated by using a one-dimensional non-isothermal model. The modeling results show that a CO concentration of less than 10 ppm and a H2 recovery of greater than 97% are achievable from reforming syngases. In an experimental study, the reversible WGS was shifted forward by removing CO2 so that the CO concentration was significantly decreased to less than 10 ppm. The modeling results agreed well with the experimental data.

The steps of activating a prospective CO 2 hydrogenation catalyst with combined CO 2 capture and reduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lao, D. B.; Galan, B. R.; Linehan, J. C.

2016-08-10

Combining carbon capture and reduction is an efficient strategy to alleviate the high energy requirements for seperation, compression, and storage of CO2 prior to reduction. Recent studies have shown that catalytic hydrogenations of CO2 can be performed without added pressure of CO2 using switchable ionic liquids. It’s ambiguous whether the alkylcarbonate (captured CO2) is reduced as it is in dynamic equilibrium with neutral CO2 in solution. New studies are presented to elucidate the reactivity of CO2 and CO2 captured in solution.

The Inherent Tracer Fingerprint of Captured CO2

NASA Astrophysics Data System (ADS)

Flude, Stephanie; Gyore, Domokos; Stuart, Finlay; Boyce, Adrian; Haszeldine, Stuart; Chalaturnyk, Rick; Gilfillan, Stuart

2017-04-01

Inherent tracers, the isotopic and trace gas composition of captured CO2 streams, are potentially powerful tracers for use in CCS technology [1,2]. Despite this potential, the inherent tracer fingerprint in captured CO2 streams has yet to be robustly investigated and documented [3]. Here, we will present the first high quality systematic measurements of the carbon and oxygen isotopic and noble gas fingerprints measured in anthropogenic CO2 captured from combustion power stations and fertiliser plants, using amine capture, oxyfuel and gasification processes, and derived from coal, biomass and natural gas feedstocks. We will show that δ13C values are mostly controlled by the feedstock composition, as expected. The majority of the CO2 samples exhibit δ18O values similar to atmospheric O2 although captured CO2 samples from biomass and gas feedstocks at one location in the UK are significantly higher. Our measured noble gas concentrations in captured CO2 are generally as expected [2], typically being two orders of magnitude lower in concentration than in atmospheric air. Relative noble gas elemental abundances are variable and often show an opposite trend to that of a water in contact with the atmosphere. Expected enrichments in radiogenic noble gases (4He and 40Ar) for fossil fuel derived CO2 were not always observed due to dilution with atmospheric noble gases during the CO2 generation and capture process. Many noble gas isotope ratios indicate that isotopic fractionation takes place during the CO2 generation and capture processes, resulting in isotope ratios similar to fractionated air. We conclude that phase changes associated with CO2 transport and sampling may induce noble gas elemental and isotopic fractionation, due to different noble gas solubilities between high (liquid or supercritical) and low (gaseous) density CO2. Data from the Australian CO2CRC Otway test site show that δ13C of CO2 will change once injected into the storage reservoir, but that this change is small and can be quantitatively modelled in order to determine the proportion of CO2 that has dissolved into the formation waters. Furthermore, noble gas data from the Otway storage reservoir post-injection, shows evidence of noble gas stripping of formation water and contamination with Kr and Xe related to an earlier injection experiment. Importantly, He data from SaskPower's Aquistore illustrates that injected CO2 will inherit distinctive crustal radiogenic noble gas fingerprints from the subsurface once injected into an undisturbed geological storage reservoir, meaning this could be used to identify unplanned migration of the CO2 to the surface and shallow subsurface [4]. References [1] Mayer et al., (2015) IJGGC, Vol. 37, 46-60 http://dx.doi.org/10.1016/j.ijggc.2015.02.021 [2] Gilfillan et al., (2014) Energy Procedia, Vol. 63, 4123-4133 http://dx.doi.org/10.1016/j.egypro.2014.11.443 [3] Flude et al., (2016) Environ. Sci. Technol., 50 (15), pp 7939-7955 DOI: 10.1021/acs.est.6b01548 [4] Gilfillan et al., (2011) IJGGC, Vol. 5 (6) 1507-1516 http://dx.doi.org/10.1016/j.ijggc.2011.08.008

How Accurately Do Maize Crop Models Simulate the Interactions of Atmospheric CO2 Concentration Levels With Limited Water Supply on Water Use and Yield?

NASA Technical Reports Server (NTRS)

Durand, Jean-Louis; Delusca, Kenel; Boote, Ken; Lizaso, Jon; Manderscheid, Remy; Weigel, Hans Johachim; Ruane, Alexander Clark; Rosenzweig, Cynthia E.; Jones, Jim; Ahuja, Laj;

Electricity without carbon dioxide: Assessing the role of carbon capture and sequestration in United States electric markets

NASA Astrophysics Data System (ADS)

Johnson, Timothy Lawrence

2002-09-01

Stabilization of atmospheric greenhouse gas concentrations will likely require significant cuts in electric sector carbon dioxide (CO2) emissions. The ability to capture and sequester CO2 in a manner compatible with today's fossil-fuel based power generating infrastructure offers a potentially low-cost contribution to a larger climate change mitigation strategy. This thesis fills a niche between economy-wide studies of CO 2 abatement and plant-level control technology assessments by examining the contribution that carbon capture and sequestration (CCS) might make toward reducing US electric sector CO2 emissions. The assessment's thirty year perspective ensures that costs sunk in current infrastructure remain relevant and allows time for technological diffusion, but remains free of assumptions about the emergence of unidentified radical innovations. The extent to which CCS might lower CO2 mitigation costs will vary directly with the dispatch of carbon capture plants in actual power-generating systems, and will depend on both the retirement of vintage capacity and competition from abatement alternatives such as coal-to-gas fuel switching and renewable energy sources. This thesis therefore adopts a capacity planning and dispatch model to examine how the current distribution of generating units, natural gas prices, and other industry trends affect the cost of CO2 control via CCS in an actual US electric market. The analysis finds that plants with CO2 capture consistently provide significant reductions in base-load emissions at carbon prices near 100 $/tC, but do not offer an economical means of meeting peak demand unless CO2 reductions in excess of 80 percent are required. Various scenarios estimate the amount by which turn-over of the existing generating infrastructure and the severity of criteria pollutant constraints reduce mitigation costs. A look at CO2 sequestration in the seabed beneath the US Outer Continental Shelf (OCS) complements this model-driven assessment by considering issues of risk, geological storage capacity, and regulation. Extensive experience with offshore oil and gas operations suggests that the technical uncertainties associated with OCS sequestration are not large. The legality of seabed CO 2 disposal under US law and international environmental agreements, however, is ambiguous, and the OCS may be the first region where these regulatory regimes clash over CO2 sequestration.

CO2 adsorption using TiO2 composite polymeric membranes: A kinetic study.

PubMed

Hafeez, Sarah; Fan, X; Hussain, Arshad; Martín, C F

2015-09-01

CO2 is the main greenhouse gas which causes global climatic changes on larger scale. Many techniques have been utilised to capture CO2. Membrane gas separation is a fast growing CO2 capture technique, particularly gas separation by composite membranes. The separation of CO2 by a membrane is not just a process to physically sieve out of CO2 through the controlled membrane pore size. It mainly depends upon diffusion and solubility of gases, particularly for composite dense membranes. The blended components in composite membranes have a high capability to adsorb CO2. The adsorption kinetics of the gases may directly affect diffusion and solubility. In this study, we have investigated the adsorption behaviour of CO2 in pure and composite membranes to explore the complete understanding of diffusion and solubility of CO2 through membranes. Pure cellulose acetate (CA) and cellulose acetate-titania nanoparticle (CA-TiO2) composite membranes were fabricated and characterised using SEM and FTIR analysis. The results indicated that the blended CA-TiO2 membrane adsorbed more quantity of CO2 gas as compared to pure CA membrane. The high CO2 adsorption capacity may enhance the diffusion and solubility of CO2 in the CA-TiO2 composite membrane, which results in a better CO2 separation. The experimental data was modelled by Pseudo first-order, pseudo second order and intra particle diffusion models. According to correlation factor R(2), the Pseudo second order model was fitted well with experimental data. The intra particle diffusion model revealed that adsorption in dense membranes was not solely consisting of intra particle diffusion. Copyright © 2015. Published by Elsevier B.V.

Absorber modeling for NGCC carbon capture with aqueous piperazine.

PubMed

Zhang, Yue; Freeman, Brice; Hao, Pingjiao; Rochelle, Gary T

2016-10-20

A hybrid system combining amine scrubbing with membrane technology for carbon capture from natural gas combined cycle (NGCC) power plants is proposed in this paper. In this process, the CO 2 in the flue gas can be enriched from 4% to 18% by the membrane, and the amine scrubbing system will have lower capture costs. Aqueous piperazine (PZ) is chosen as the solvent. Different direct contact cooler (DCC) options, multiple absorber operating conditions, optimal intercooling designs, and different cooling options have been evaluated across a wide range of inlet CO 2 . Amine scrubbing without DCC is a superior design for NGCC carbon capture. Pump-around cooling at the bottom of the absorber can effectively manage the temperature of the hot flue gas, and still be effective for CO 2 absorption. The absorber gas inlet must be designed to avoid excessive localized temperature and solvent evaporation. When the inlet CO 2 increases from 4% to 18%, total absorber CAPEX decreases by 60%; another 10% of the total absorber CAPEX can be saved by eliminating the DCC. In-and-out intercooling works well for high CO 2 , while pump-around intercooling is more effective for low CO 2 . Dry cooling requires more packing and energy but appears to be technically and economically feasible if cooling water availability is limited.

Measuring the Absorption Rate of CO 2 in Nonaqueous CO 2 -Binding Organic Liquid Solvents with a Wetted-Wall Apparatus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mathias, Paul M.; Zheng, Feng; Heldebrant, David J.

2015-09-17

The kinetics of the absorption of CO 2 into two nonaqueous CO 2-binding organic liquid (CO 2BOL) solvents were measured at T=35, 45, and 55 °C with a wetted-wall column. Selected CO 2 loadings were run with a so-called “first-generation” CO 2BOL, comprising an independent base and alcohol, and a “second-generation” CO 2BOL, in which the base and alcohol were conjoined. Liquid-film mass-transfer coefficient (k'g) values for both solvents were measured to be comparable to values for monoethanolamine and piperazine aqueous solvents under a comparable driving force, in spite of far higher solution viscosities. An inverse temperature dependence of themore » k'g value was also observed, which suggests that the physical solubility of CO 2 in organic liquids may be making CO 2 mass transfer faster than expected. Aspen Plus software was used to model the kinetic data and compare the CO 2 absorption behavior of nonaqueous solvents with that of aqueous solvent platforms. This work continues our development of the CO2BOL solvents. Previous work established the thermodynamic properties related to CO 2 capture. The present paper quantitatively studies the kinetics of CO 2 capture and develops a rate-based model.« less

Pathway To Low-Carbon Lignite Utilization; U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) Cooperative Agreement No. DE-FE0024233

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kay, John; Stanislowski, Joshua; Tolbert, Scott

Utilities continue to investigate ways to decrease their carbon footprint. Carbon capture and storage (CCS) can enable existing power generation facilities to maintain operations and address carbon reduction. Subtask 2.1 – Pathway to Low-Carbon Lignite Utilization focused on several research areas in an effort to find ways to decrease the cost of capture across both precombustion and postcombustion platforms. Two postcombustion capture solvents were tested, one from CO 2 Solutions Inc. and one from ARCTECH, Inc. The CO 2 Solutions solvent had been evaluated previously, and the company had incorporated the concept of a rotating packed bed (RPB) to replacemore » the traditional packed columns typically used. In the limited testing performed at the Energy & Environmental Research Center (EERC), no CO 2 reduction benefit was seen from the RPB; however, if the technology could be scaled up, it may introduce some savings in capital expense and overall system footprint. Rudimentary tests were conducted with the ARCTECH solvent to evaluate if it could be utilized in a spray tower configuration contactor and capture CO 2, SO 2, and NO x. This solvent after loading can be processed to make an additional product to filter wastewater, providing a second-tier usable product. Modeling of the RPB process for scaling to a 550-MW power system was also conducted. The reduced cost of RPB systems combined with a smaller footprint highlight the potential for reducing the cost of capturing CO 2; however, more extensive testing is needed to truly evaluate their potential for use at full scale. Hydrogen separation membranes from Commonwealth Scientific and Industrial Research Organisation (CSIRO) were evaluated through precombustion testing. These had also been previously tested and were improved by CSIRO for this test campaign. They are composed of vanadium alloy, which is less expensive than the palladium alloys that are typically used. Their performance was good, and they may be good candidates for medium-pressure gasifiers, but much more scale-up work is needed. Next-generation power cycles are currently being developed and show promise for high efficiency, and the utilization of supercritical CO 2 to drive a turbine could significantly increase cycle efficiency over traditional steam cycles. The EERC evaluated pressurized oxy-combustion technology from the standpoint of CO 2 purification. If impurities can be removed, the costs for CO 2 capture can be lowered significantly over postcombustion capture systems. Impurity removal consisted of a simple water scrubber referred to as the DeSNO x process. The process worked well, but corrosion management is crucial to its success. A model of this process was constructed. Finally, an integrated gasification combined-cycle (IGCC) system model, developed by the Massachusetts Institute of Technology (MIT), was modified to allow for the modeling of membrane systems in the IGCC process. This modified model was used to provide an assessment of the costs of membrane use at full scale. An economic estimation indicated a 14% reduction in cost for CO 2 separation over the SELEXOL™ process. This subtask was funded through the EERC–DOE Joint Program on Research and Development for Fossil Energy-Related Resources Cooperative Agreement No. DE-FE0024233. Nonfederal sponsors for this project were the North Dakota Industrial Commission, Basin Electric Power Cooperative, and Allete, Inc. (including BNI Coal and Minnesota Power).« less

Fingerprinting captured CO2 using natural tracers: Determining CO2 fate and proving ownership

NASA Astrophysics Data System (ADS)

Flude, Stephanie; Gilfillan, Stuart; Johnston, Gareth; Stuart, Finlay; Haszeldine, Stuart

2016-04-01

In the long term, captured CO2 will most likely be stored in large saline formations and it is highly likely that CO2 from multiple operators will be injected into a single saline formation. Understanding CO2 behavior within the reservoir is vital for making operational decisions and often uses geochemical techniques. Furthermore, in the event of a CO2 leak, being able to identify the owner of the CO2 is of vital importance in terms of liability and remediation. Addition of geochemical tracers to the CO2 stream is an effective way of tagging the CO2 from different power stations, but may become prohibitively expensive at large scale storage sites. Here we present results from a project assessing whether the natural isotopic composition (C, O and noble gas isotopes) of captured CO2 is sufficient to distinguish CO2 captured using different technologies and from different fuel sources, from likely baseline conditions. Results include analytical measurements of CO2 captured from a number of different CO2 capture plants and a comprehensive literature review of the known and hypothetical isotopic compositions of captured CO2 and baseline conditions. Key findings from the literature review suggest that the carbon isotope composition will be most strongly controlled by that of the feedstock, but significant fractionation is possible during the capture process; oxygen isotopes are likely to be controlled by the isotopic composition of any water used in either the industrial process or the capture technology; and noble gases concentrations will likely be controlled by the capture technique employed. Preliminary analytical results are in agreement with these predictions. Comparison with summaries of likely storage reservoir baseline and shallow or surface leakage reservoir baseline data suggests that C-isotopes are likely to be valuable tracers of CO2 in the storage reservoir, while noble gases may be particularly valuable as tracers of potential leakage.

A New Method for Breath Capture Inside a Space Suit Helmet

NASA Technical Reports Server (NTRS)

Filburn, Tom; Dolder, Craig; Tufano, Brett; Paul, Heather L.

2007-01-01

This project investigates methods to capture an astronaut's exhaled carbon dioxide (CO2) before it becomes diluted with the high volumetric oxygen flow present within a space suit. Typical expired breath contains CO2 partial pressures (pCO2) in the range of 20-35 mm Hg. This research investigates methods to capture the concentrated CO2 gas stream prior to its dilution with the low pCO2 ventilation flow. Specifically this research is looking at potential designs for a collection cup for use inside the space suit helmet. The collection cup concept is not the same as a breathing mask typical of that worn by firefighters and pilots. It is well known that most members of the astronaut corps view a mask as a serious deficiency in any space suit helmet design. Instead, the collection cup is a non-contact device that will be designed using a detailed Computational Fluid Dynamic (CFD) analysis of the ventilation flow environment within the helmet. The CFD code, Fluent, provides modeling of the various gas species (CO2, water vapor, and oxygen (O2)) as they pass through a helmet. This same model will be used to numerically evaluate several different collection cup designs for this same CO2 segregation effort. A new test rig will be built to test the results of the CFD analyses and validate the collection cup designs. This paper outlines the initial results and future plans of this work.

Comparative efficiency of two models of CO2 traps in the collection of free-living stages of ixodides.

PubMed

Guedes, Elizângela; de Azevedo Prata, Márcia Cristina; dos Reis, Eder Sebastião; Cançado, Paulo Henrique Duarte; Leite, Romário Cerqueira

2012-12-01

Traps using carbon dioxide (CO(2)) as a chemical attractant are known to be effective when capturing nymphs and adults of some free-living tick species such as Amblyomma cajennense and Amblyomma parvum. Despite the fact that the main source of CO(2) is dry ice, the chemical trap which uses 20 % lactic acid (C(3)H(6)O(3)) and calcium carbonate (CaCO(3)) has been tested as an alternative source of CO(2) whenever it is difficult to obtain dry ice. The objective of this paper was to test and compare the efficiency of these two models of traps during the study of population dynamics of A. cajennense and Amblyomma dubitatum in Coronel Pacheco, Minas Gerais, Brazil. Within the period comprising May 2006 to April 2008, eight CO(2) traps, of which four were dry ice and four chemical, were put in the pasture every 14 days at preestablished areas over a 1.0-m(2) white cotton flannel cloth with a capture dispositive which constituted of double-sided adhesive tapes fixed onto the four corners of the flannels. On every collection day, a cotton flannel without any chemical attractant was placed in the same area of the pasture to become an instrument to control the traps' capture efficiency. After 1 h, the white flannels were collected and placed in plastic bags for later identification and counting of the ticks. A total of 2,133 nymphs of Amblyomma sp., 328 adults of A. cajennense, and 292 adults of A. dubitatum were collected. Out of this total, the dry ice traps captured 1,087 nymphs (51 %), 188 A. cajennense (58.2 %), and 151 A. dubitatum (53 %), while the chemical traps captured 1,016 nymphs (47.6 %), 133 A. cajennense (41 %), and 133 A. dubitatum (46.5 %); 30 nymphs (1.4 %), 7 A. cajennense (0.8 %), and 8 A. dubitatum (0.5 %) were found on the control flannel. The capture potentials of ticks, nymphs, and adults, by the two models of traps tested, were statistically similar (p > 0.05). These results confirm the efficiency of the chemical trap enabling its use in areas of either difficult access or too distant from a dry ice supplier as is the case of forest areas where studies about ixodological fauna are generally carried out.

Recent enlightening strategies for co2 capture: a review

NASA Astrophysics Data System (ADS)

Yuan, Peng; Qiu, Ziyang; Liu, Jia

2017-05-01

The global climate change has seriously affected the survival and prosperity of mankind, where greenhouse effect owing to atmospheric carbon dioxide (CO2) enrichment is a great cause. Accordingly, a series of down-to-earth measures need to be implemented urgently to control the output of CO2. As CO2 capture appears as a core issue in developing low-carbon economy, this review provides a comprehensive introduction of recent CO2 capture technologies used in power plants or other industries. Strategies for CO2 capture, e.g. pre-combustion, post-combustion and oxyfuel combustion, are covered in this article. Another enlightening technology for CO2 capture based on fluidized beds is intensively discussed.

Economic and energetic analysis of capturing CO2 from ambient air

PubMed Central

House, Kurt Zenz; Baclig, Antonio C.; Ranjan, Manya; van Nierop, Ernst A.; Wilcox, Jennifer; Herzog, Howard J.

2011-01-01

Capturing carbon dioxide from the atmosphere (“air capture”) in an industrial process has been proposed as an option for stabilizing global CO2 concentrations. Published analyses suggest these air capture systems may cost a few hundred dollars per tonne of CO2, making it cost competitive with mainstream CO2 mitigation options like renewable energy, nuclear power, and carbon dioxide capture and storage from large CO2 emitting point sources. We investigate the thermodynamic efficiencies of commercial separation systems as well as trace gas removal systems to better understand and constrain the energy requirements and costs of these air capture systems. Our empirical analyses of operating commercial processes suggest that the energetic and financial costs of capturing CO2 from the air are likely to have been underestimated. Specifically, our analysis of existing gas separation systems suggests that, unless air capture significantly outperforms these systems, it is likely to require more than 400 kJ of work per mole of CO2, requiring it to be powered by CO2-neutral power sources in order to be CO2 negative. We estimate that total system costs of an air capture system will be on the order of $1,000 per tonne of CO2, based on experience with as-built large-scale trace gas removal systems. PMID:22143760

Ship-in-a-bottle synthesis of amine-functionalized ionic liquids in NaY zeolite for CO2 capture

PubMed Central

Yu, Yinghao; Mai, Jingzhang; Wang, Lefu; Li, Xuehui; Jiang, Zheng; Wang, Furong

2014-01-01

CO2 capture on solid materials possesses significant advantages on the operation cost, process for large-scale CO2 capture and storage (CCS) that stimulates great interest in exploring high-performance solid CO2 adsorbents. A ship-in-a-bottle strategy was successfully developed to prepare the [APMIM]Br@NaY host–guest system in which an amine-functionalized ionic liquid (IL), 1-aminopropyl-3-methylimidazolium bromide ([APMIM]Br), was in-situ encapsulated in the NaY supercages. The genuine host-guest systems were thoroughly characterized and tested in CO2 capture from simulated flue gas. It was evidenced the encapsulated ILs are more stable than the bulk ILs. These host–guest systems exhibited superb overall CO2 capture capacity up to 4.94 mmol g−1 and the chemically adsorbed CO2 achieved 1.85 mmol g−1 depending on the [APMIM]Br loading amount. The chemisorbed CO2 can be desorbed rapidly by flushing with N2 gas at 50°C. The optimized [APMIM]Br@NaY system remains its original CO2 capture capacity in multiple cycling tests under prolonged harsh adsorption-desorption conditions. The excellent physicochemical properties and the CO2 capture performance of the host-guest systems offer them great promise for the future practice in the industrial CO2 capture. PMID:25104324

CO2 Capture from the Air: Technology Assessment and Implications for Climate Policy

NASA Astrophysics Data System (ADS)

Keith, D. W.

2002-05-01

It is physically possible to capture CO2 directly from the air and immobilize it in geological structures. Today, there are no large-scale technologies that achieve air capture at reasonable cost. Yet, strong arguments suggest that it will comparatively easy to develop practical air capture technologies on the timescales relevant to climate policy [1]. This paper first analyzes the cost of air capture and then assesses the implications for climate policy. We first analyze the lower bound on the cost needed for air capture, describing the thermodynamic and physical limits to the use of energy and land. We then compare the costs of air capture to the cost of capture from combustion exhaust streams. While the intrinsic minimum energy requirement is larger for air capture, we argue that air capture has important structural advantages, such as the reduction of transport costs and the larger potential for economies of scale. These advantages suggest that, in the long-run air capture be competitive with other methods of achieving deep emissions reductions. We provide a preliminary engineering-economic analysis of an air capture system based on CaO to CaCO3 chemical looping [1]. We analyze the possibility of doing the calcination in a modified pressurized fluidized bed combustor (PFBC) burning coal in a CO2 rich atmosphere with oxygen supplied by an air separation unit. The CaCO3-to-coal ratio would be ~2:1 and the system would be nearly thermally neutral. PFBC systems have been demonstrated at capacities of over 100 MW. Such systems already include CaCO3 injection for sulfur control, and operate at suitable temperatures and pressures for calcination. We assess the potential to recover heat from the dissolution of CaO in order to reduce the overall energy requirements. We analyze the possibility of adapting existing large water/air heat exchangers for use as contacting systems to capture CO2 from the air using the calcium hydroxide solution. The implications of air capture for global climate policy are examined using DIAM [2], a stylized integrated assessment model. We find that air capture can fundamentally alter the temporal dynamics of global warming mitigation. The reason for this is that air capture differs from conventional mitigation in three key aspects. First, it removes emissions from any part of the economy with equal ease or difficulty, so its cost provides an absolute cap on the cost of mitigation. Second, it permits reduction in concentrations faster than the natural carbon cycle: the effects of irreversibility are thus partly alleviated. Third, because it is less coupled with the energy system, air capture may offer stronger economies of scale and smaller adjustment costs than the more conventional mitigation technologies. Air capture limits the total cost of a worst-case climate scenario. In an optimal sequential decision framework with uncertainty, existence of air capture decreases the need for near-term precautionary abatement. Like geoengineering, air capture thus poses a moral hazard. 1. S. Elliott, et al. Compensation of atmospheric CO2 buildup through engineered chemical sinkage. Geophys. Res. Let., 28:1235-1238, 2001. 2. Minh Ha-Duong, Michael J. Grubb, and Jean-Charles Hourcade. Influence of socioeconomic inertia and uncertainty on optimal CO2-emission abatement. Nature, 390: 270-274, 1997.

Evaluation of Thermodynamic Models for Predicting Phase Equilibria of CO2 + Impurity Binary Mixture

NASA Astrophysics Data System (ADS)

Shin, Byeong Soo; Rho, Won Gu; You, Seong-Sik; Kang, Jeong Won; Lee, Chul Soo

2018-03-01

For the design and operation of CO2 capture and storage (CCS) processes, equation of state (EoS) models are used for phase equilibrium calculations. Reliability of an EoS model plays a crucial role, and many variations of EoS models have been reported and continue to be published. The prediction of phase equilibria for CO2 mixtures containing SO2, N2, NO, H2, O2, CH4, H2S, Ar, and H2O is important for CO2 transportation because the captured gas normally contains small amounts of impurities even though it is purified in advance. For the design of pipelines in deep sea or arctic conditions, flow assurance and safety are considered priority issues, and highly reliable calculations are required. In this work, predictive Soave-Redlich-Kwong, cubic plus association, Groupe Européen de Recherches Gazières (GERG-2008), perturbed-chain statistical associating fluid theory, and non-random lattice fluids hydrogen bond EoS models were compared regarding performance in calculating phase equilibria of CO2-impurity binary mixtures and with the collected literature data. No single EoS could cover the entire range of systems considered in this study. Weaknesses and strong points of each EoS model were analyzed, and recommendations are given as guidelines for safe design and operation of CCS processes.

How accurately do maize crop models simulate the interactions of atmospheric CO2 concentration levels with limited water supply on water use and yield?

USDA-ARS?s Scientific Manuscript database

This study assesses the ability of 21 crop models to capture the impact of elevated CO2 concentration ([CO218 ]) on maize yield and water use as measured in a 2-year Free Air Carbon dioxide Enrichment experiment conducted at the Thünen Institute in Braunschweig, Germany (Manderscheid et al. 2014). D...

Conductive Graphitic Carbon Nitride as an Ideal Material for Electrocatalytically Switchable CO2 Capture

PubMed Central

Tan, Xin; Kou, Liangzhi; Tahini, Hassan A.; Smith, Sean C.

2015-01-01

Good electrical conductivity and high electron mobility of the sorbent materials are prerequisite for electrocatalytically switchable CO2 capture. However, no conductive and easily synthetic sorbent materials are available until now. Here, we examined the possibility of conductive graphitic carbon nitride (g-C4N3) nanosheets as sorbent materials for electrocatalytically switchable CO2 capture. Using first-principle calculations, we found that the adsorption energy of CO2 molecules on g-C4N3 nanosheets can be dramatically enhanced by injecting extra electrons into the adsorbent. At saturation CO2 capture coverage, the negatively charged g-C4N3 nanosheets achieve CO2 capture capacities up to 73.9 × 1013 cm−2 or 42.3 wt%. In contrast to other CO2 capture approaches, the process of CO2 capture/release occurs spontaneously without any energy barriers once extra electrons are introduced or removed, and these processes can be simply controlled and reversed by switching on/off the charging voltage. In addition, these negatively charged g-C4N3 nanosheets are highly selective for separating CO2 from mixtures with CH4, H2 and/or N2. These predictions may prove to be instrumental in searching for a new class of experimentally feasible high-capacity CO2 capture materials with ideal thermodynamics and reversibility. PMID:26621618

Innovative nano-layered solid sorbents for CO2 capture.

PubMed

Li, Bingyun; Jiang, Bingbing; Fauth, Daniel J; Gray, McMahan L; Pennline, Henry W; Richards, George A

2011-02-14

Nano-layered sorbents for CO(2) capture, for the first time, were developed using layer-by-layer nanoassembly. A CO(2)-adsorbing polymer and a strong polyelectrolyte were alternately immobilized within porous particles. The developed sorbents had fast CO(2) adsorption and desorption properties and their CO(2) capture capacity increased with increasing nano-layers of the CO(2)-adsorbing polymer.

Surface modification of a low cost bentonite for post-combustion CO2 capture

NASA Astrophysics Data System (ADS)

Chen, Chao; Park, Dong-Wha; Ahn, Wha-Seung

2013-10-01

A low cost bentonite was modified with PEI (polyethylenimine) through a physical impregnation method. Bentonite in its natural state and after amine modification were characterized by scanning electron microscopy-energy dispersive X-ray spectroscopy, X-ray diffraction, N2 adsorption-desorption isotherms, and investigated for CO2 capture using a thermogravimetric analysis unit connected to a flow panel. The effect of adsorption temperature, PEI loading and CO2 partial pressure on the CO2 capture performance of the PEI-modified bentonite was examined. A cyclic CO2 adsorption-desorption test was also carried out to assess the stability of PEI-modified bentonite as a CO2 adsorbent. Bentonite in its natural state showed negligible CO2 uptake. After amine modification, the CO2 uptake increased significantly due to CO2 capture by amine species introduced via chemisorption. The PEI-modified bentonites showed high CO2 capture selectivity over N2, and exhibited excellent stability in cyclic CO2 adsorption-desorption runs.

Device-scale CFD modeling of gas-liquid multiphase flow and amine absorption for CO 2 capture: Original Research Article: Device-scale CFD modeling of gas-liquid multiphase flow and amine absorption for CO 2 capture

DOE PAGES

Pan, Wenxiao; Galvin, Janine; Huang, Wei Ling; ...

2018-03-25

In this paper we aim to develop a validated device-scale CFD model that can predict quantitatively both hydrodynamics and CO 2 capture efficiency for an amine-based solvent absorber column with random Pall ring packing. A Eulerian porous-media approach and a two-fluid model were employed, in which the momentum and mass transfer equations were closed by literature-based empirical closure models. We proposed a hierarchical approach for calibrating the parameters in the closure models to make them accurate for the packed column. Specifically, a parameter for momentum transfer in the closure was first calibrated based on data from a single experiment. Withmore » this calibrated parameter, a parameter in the closure for mass transfer was next calibrated under a single operating condition. Last, the closure of the wetting area was calibrated for each gas velocity at three different liquid flow rates. For each calibration, cross validations were pursued using the experimental data under operating conditions different from those used for calibrations. This hierarchical approach can be generally applied to develop validated device-scale CFD models for different absorption columns.« less

Device-scale CFD modeling of gas-liquid multiphase flow and amine absorption for CO 2 capture: Original Research Article: Device-scale CFD modeling of gas-liquid multiphase flow and amine absorption for CO 2 capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Wenxiao; Galvin, Janine; Huang, Wei Ling

In this paper we aim to develop a validated device-scale CFD model that can predict quantitatively both hydrodynamics and CO 2 capture efficiency for an amine-based solvent absorber column with random Pall ring packing. A Eulerian porous-media approach and a two-fluid model were employed, in which the momentum and mass transfer equations were closed by literature-based empirical closure models. We proposed a hierarchical approach for calibrating the parameters in the closure models to make them accurate for the packed column. Specifically, a parameter for momentum transfer in the closure was first calibrated based on data from a single experiment. Withmore » this calibrated parameter, a parameter in the closure for mass transfer was next calibrated under a single operating condition. Last, the closure of the wetting area was calibrated for each gas velocity at three different liquid flow rates. For each calibration, cross validations were pursued using the experimental data under operating conditions different from those used for calibrations. This hierarchical approach can be generally applied to develop validated device-scale CFD models for different absorption columns.« less

Kinetic analysis of an anion exchange absorbent for CO2 capture from ambient air.

PubMed

Shi, Xiaoyang; Li, Qibin; Wang, Tao; Lackner, Klaus S

2017-01-01

This study reports a preparation method of a new moisture swing sorbent for CO2 capture from air. The new sorbent components include ion exchange resin (IER) and polyvinyl chloride (PVC) as a binder. The IER can absorb CO2 when surrounding is dry and release CO2 when surrounding is wet. The manuscript presents the studies of membrane structure, kinetic model of absorption process, performance of desorption process and the diffusivity of water molecules in the CO2 absorbent. It has been proved that the kinetic performance of CO2 absorption/desorption can be improved by using thin binder and hot water treatment. The fast kinetics of P-100-90C absorbent is due to the thin PVC binder, and high diffusion rate of H2O molecules in the sample. The impressive is this new CO2 absorbent has the fastest CO2 absorption rate among all absorbents which have been reported by other up-to-date literatures.

Kinetic analysis of an anion exchange absorbent for CO2 capture from ambient air

PubMed Central

Shi, Xiaoyang; Li, Qibin; Lackner, Klaus S.

2017-01-01

This study reports a preparation method of a new moisture swing sorbent for CO2 capture from air. The new sorbent components include ion exchange resin (IER) and polyvinyl chloride (PVC) as a binder. The IER can absorb CO2 when surrounding is dry and release CO2 when surrounding is wet. The manuscript presents the studies of membrane structure, kinetic model of absorption process, performance of desorption process and the diffusivity of water molecules in the CO2 absorbent. It has been proved that the kinetic performance of CO2 absorption/desorption can be improved by using thin binder and hot water treatment. The fast kinetics of P-100-90C absorbent is due to the thin PVC binder, and high diffusion rate of H2O molecules in the sample. The impressive is this new CO2 absorbent has the fastest CO2 absorption rate among all absorbents which have been reported by other up-to-date literatures. PMID:28640914

Multishelled CaO Microspheres Stabilized by Atomic Layer Deposition of Al2 O3 for Enhanced CO2 Capture Performance.

PubMed

Armutlulu, Andac; Naeem, Muhammad Awais; Liu, Hsueh-Ju; Kim, Sung Min; Kierzkowska, Agnieszka; Fedorov, Alexey; Müller, Christoph R

2017-11-01

CO 2 capture and storage is a promising concept to reduce anthropogenic CO 2 emissions. The most established technology for capturing CO 2 relies on amine scrubbing that is, however, associated with high costs. Technoeconomic studies show that using CaO as a high-temperature CO 2 sorbent can significantly reduce the costs of CO 2 capture. A serious disadvantage of CaO derived from earth-abundant precursors, e.g., limestone, is the rapid, sintering-induced decay of its cyclic CO 2 uptake. Here, a template-assisted hydrothermal approach to develop CaO-based sorbents exhibiting a very high and cyclically stable CO 2 uptake is exploited. The morphological characteristics of these sorbents, i.e., a porous shell comprised of CaO nanoparticles coated by a thin layer of Al 2 O 3 (<3 nm) containing a central void, ensure (i) minimal diffusion limitations, (ii) space to accompany the substantial volumetric changes during CO 2 capture and release, and (iii) a minimal quantity of Al 2 O 3 for structural stabilization, thus maximizing the fraction of CO 2 -capture-active CaO. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evaluating the climate benefits of CO2-enhanced oil recovery using life cycle analysis.

PubMed

Cooney, Gregory; Littlefield, James; Marriott, Joe; Skone, Timothy J

2015-06-16

This study uses life cycle analysis (LCA) to evaluate the greenhouse gas (GHG) performance of carbon dioxide (CO2) enhanced oil recovery (EOR) systems. A detailed gate-to-gate LCA model of EOR was developed and incorporated into a cradle-to-grave boundary with a functional unit of 1 MJ of combusted gasoline. The cradle-to-grave model includes two sources of CO2: natural domes and anthropogenic (fossil power equipped with carbon capture). A critical parameter is the crude recovery ratio, which describes how much crude is recovered for a fixed amount of purchased CO2. When CO2 is sourced from a natural dome, increasing the crude recovery ratio decreases emissions, the opposite is true for anthropogenic CO2. When the CO2 is sourced from a power plant, the electricity coproduct is assumed to displace existing power. With anthropogenic CO2, increasing the crude recovery ratio reduces the amount of CO2 required, thereby reducing the amount of power displaced and the corresponding credit. Only the anthropogenic EOR cases result in emissions lower than conventionally produced crude. This is not specific to EOR, rather the fact that carbon-intensive electricity is being displaced with captured electricity, and the fuel produced from that system receives a credit for this displacement.

Energy and material balance of CO2 capture from ambient air.

PubMed

Zeman, Frank

2007-11-01

Current Carbon Capture and Storage (CCS) technologies focus on large, stationary sources that produce approximately 50% of global CO2 emissions. We propose an industrial technology that captures CO2 directly from ambient air to target the remaining emissions. First, a wet scrubbing technique absorbs CO2 into a sodium hydroxide solution. The resultant carbonate is transferred from sodium ions to calcium ions via causticization. The captured CO2 is released from the calcium carbonate through thermal calcination in a modified kiln. The energy consumption is calculated as 350 kJ/mol of CO2 captured. It is dominated by the thermal energy demand of the kiln and the mechanical power required for air movement. The low concentration of CO2 in air requires a throughput of 3 million cubic meters of air per ton of CO2 removed, which could result in significant water losses. Electricity consumption in the process results in CO2 emissions and the use of coal power would significantly reduce to net amount captured. The thermodynamic efficiency of this process is low but comparable to other "end of pipe" capture technologies. As another carbon mitigation technology, air capture could allow for the continued use of liquid hydrocarbon fuels in the transportation sector.

Bench-Scale Silicone Process for Low-Cost CO{sub 2} Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vipperla, Ravikumar; Yee, Michael; Steele, Ray

This report presents system and economic analysis for a carbon capture unit which uses an amino-silicone solvent for CO{sub 2} capture and sequestration (CCS) in a pulverized coal (PC) boiler. The amino-silicone solvent is based on GAP-1 with Tri-Ethylene Glycol (TEG) as a co-solvent. The report also shows results for a CCS unit based on a conventional approach using mono-ethanol amine (MEA). Models were developed for both processes and used to calculate mass and energy balances. Capital costs and energy penalty were calculated for both systems, as well as the increase in cost of electricity. The amino-silicone solvent based systemmore » demonstrates significant advantages compared to the MEA system.« less

Technoeconomic Assessment of an Advanced Aqueous Ammonia-Based Postcombustion Capture Process Integrated with a 650-MW Coal-Fired Power Station.

PubMed

Li, Kangkang; Yu, Hai; Yan, Shuiping; Feron, Paul; Wardhaugh, Leigh; Tade, Moses

2016-10-04

Using a rigorous, rate-based model and a validated economic model, we investigated the technoeconomic performance of an aqueous NH 3 -based CO 2 capture process integrated with a 650-MW coal-fired power station. First, the baseline NH 3 process was explored with the process design of simultaneous capture of CO 2 and SO 2 to replace the conventional FGD unit. This reduced capital investment of the power station by US$425/kW (a 13.1% reduction). Integration of this NH 3 baseline process with the power station takes the CO 2 -avoided cost advantage over the MEA process (US$67.3/tonne vs US$86.4/tonne). We then investigated process modifications of a two-stage absorption, rich-split configuration and interheating stripping to further advance the NH 3 process. The modified process reduced energy consumption by 31.7 MW/h (20.2% reduction) and capital costs by US$55.4 million (6.7% reduction). As a result, the CO 2 -avoided cost fell to $53.2/tonne: a savings of $14.1 and $21.9/tonne CO 2 compared with the NH 3 baseline and advanced MEA process, respectively. The analysis of energy breakdown and cost distribution indicates that the technoeconomic performance of the NH 3 process still has great potential to be improved.

Final Techno-Economic Analysis of 550 MWe Supercritical PC Power Plant CO 2 Capture with Linde-BASF Advanced PCC Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bostick, Devin; Stoffregen, Torsten; Rigby, Sean

This topical report presents the techno-economic evaluation of a 550 MWe supercritical pulverized coal (PC) power plant utilizing Illinois No. 6 coal as fuel, integrated with 1) a previously presented (for a subcritical PC plant) Linde-BASF post-combustion CO 2 capture (PCC) plant incorporating BASF’s OASE® blue aqueous amine-based solvent (LB1) [Ref. 6] and 2) a new Linde-BASF PCC plant incorporating the same BASF OASE® blue solvent that features an advanced stripper interstage heater design (SIH) to optimize heat recovery in the PCC process. The process simulation and modeling for this report is performed using Aspen Plus V8.8. Technical information frommore » the PCC plant is determined using BASF’s proprietary thermodynamic and process simulation models. The simulations developed and resulting cost estimates are first validated by reproducing the results of DOE/NETL Case 12 representing a 550 MWe supercritical PC-fired power plant with PCC incorporating a monoethanolamine (MEA) solvent as used in the DOE/NETL Case 12 reference [Ref. 2]. The results of the techno-economic assessment are shown comparing two specific options utilizing the BASF OASE® blue solvent technology (LB1 and SIH) to the DOE/NETL Case 12 reference. The results are shown comparing the energy demand for PCC, the incremental fuel requirement, and the net higher heating value (HHV) efficiency of the PC power plant integrated with the PCC plant. A comparison of the capital costs for each PCC plant configuration corresponding to a net 550 MWe power generation is also presented. Lastly, a cost of electricity (COE) and cost of CO 2 captured assessment is shown illustrating the substantial cost reductions achieved with the Linde-BASF PCC plant utilizing the advanced SIH configuration in combination with BASF’s OASE® blue solvent technology as compared to the DOE/NETL Case 12 reference. The key factors contributing to the reduction of COE and the cost of CO 2 captured, along with quantification of the magnitude of the reductions achieved by each of these factors, are also discussed. Additionally, a high-level techno-economic analysis of one more highly advanced Linde-BASF PCC configuration case (LB1-CREB) is also presented to demonstrate the significant impact of innovative PCC plant process design improvements on further reducing COE and cost of CO 2 captured for overall plant cost and performance comparison purposes. Overall, the net efficiency of the integrated 550 MWe supercritical PC power plant with CO 2 capture is increased from 28.4% with the DOE/NETL Case 12 reference to 30.9% with the Linde-BASF PCC plant previously presented utilizing the BASF OASE® blue solvent [Ref. 6], and is further increased to 31.4% using Linde-BASF PCC plant with BASF OASE® blue solvent and an advanced SIH configuration. The Linde-BASF PCC plant incorporating the BASF OASE® blue solvent also results in significantly lower overall capital costs, thereby reducing the COE and cost of CO 2 captured from $147.25/MWh and $56.49/MT CO 2, respectively, for the reference DOE/NETL Case 12 plant, to $128.49/MWh and $41.85/MT CO 2 for process case LB1, respectively, and $126.65/MWh and $40.66/MT CO 2 for process case SIH, respectively. With additional innovative Linde-BASF PCC process configuration improvements, the COE and cost of CO2 captured can be further reduced to $125.51/MWh and $39.90/MT CO 2 for LB1-CREB. Most notably, the Linde-BASF process options presented here have already demonstrated the potential to lower the cost of CO2 captured below the DOE target of $40/MT CO 2 at the 550 MWe scale for second generation PCC technologies.« less

Feasibility study of algae-based Carbon Dioxide capture ...

EPA Pesticide Factsheets

SUMMARY: The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being undertaken to evaluate the benefits of using algae to reduce CO2 emissions from industrial and small-scale utility power boilers. The operations are being studied for the use of CO2 from flue gas for algae growth along with the production of biofuels and other useful products to prepare a comprehensive characterization of the economic feasibility of using algae to capture CO2. Information is being generated for analyses of the potential for these technologies to advance in the market and assist in meeting environmental goals, as well as to examine their associated environmental implications. Three electric power generation plants (coal and fuel oil fired) equipped to send flue-gas emissions to algae culture at demonstration facilities are being studied. Data and process information are being collected and developed to facilitate feasibility and modeling evaluations of the CO2 to algae technology. An understanding of process requirements to apply this technology to existing industries would go far in advancing carbon capture opportunities. Documenting the successful use of this technology could help bring “low-tech”, low-cost, CO2 to algae, carbon capture to multiple size industries and

Synergistic Carbon Dioxide Capture and Conversion in Porous Materials.

PubMed

Zhang, Yugen; Lim, Diane S W

2015-08-24

Global climate change and excessive CO2 emissions have caused widespread public concern in recent years. Tremendous efforts have been made towards CO2 capture and conversion. This has led to the development of numerous porous materials as CO2 capture sorbents. Concurrently, the conversion of CO2 into value-added products by chemical methods has also been well-documented recently. However, realizing the attractive prospect of direct, in situ chemical conversion of captured CO2 into other chemicals remains a challenge. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bench Scale Process for Low Cost CO 2 Capture Using a PhaseChanging Absorbent: Techno-Economic Analysis Topical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miebach, Barbara; McDuffie, Dwayne; Spiry, Irina

The objective of this project is to design and build a bench-scale process for a novel phase-changing CO 2 capture solvent. The project will establish scalability and technical and economic feasibility of using a phase-changing CO 2 capture absorbent for post-combustion capture of CO 2 from coal-fired power plants with 90% capture efficiency and 95% CO 2 purity at a cost of $40/tonne of CO 2 captured by 2025 and a cost of <$10/tonne of CO 2 captured by 2035. This report presents system and economic analysis for a process that uses a phase changing aminosilicone solvent to remove COmore » 2 from pulverized coal (PC) power plant flue gas. The aminosilicone solvent is a pure 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane (GAP-0). Performance of the phase-changing aminosilicone technology is compared to that of a conventional carbon capture system using aqueous monoethanolamine (MEA). This analysis demonstrates that the aminosilicone process has significant advantages relative to an MEA-based system. The first-year CO 2 removal cost for the phase-changing CO 2 capture process is $52.1/tonne, compared to $66.4/tonne for the aqueous amine process. The phase-changing CO 2 capture process is less costly than MEA because of advantageous solvent properties that include higher working capacity, lower corrosivity, lower vapor pressure, and lower heat capacity. The phase-changing aminosilicone process has approximately 32% lower equipment capital cost compared to that of the aqueous amine process. However, this solvent is susceptible to thermal degradation at CSTR desorber operating temperatures, which could add as much as $88/tonne to the CO 2 capture cost associated with solvent makeup. Future work is focused on mitigating this critical risk by developing an advanced low-temperature desorber that can deliver comparable desorption performance and significantly reduced thermal degradation rate.« less

Reinventing Design Principles for Developing Low-Viscosity Carbon Dioxide-Binding Organic Liquids for Flue Gas Clean Up

DOE Office of Scientific and Technical Information (OSTI.GOV)

None, None

2017-01-11

Anthropogenic carbon dioxide (CO 2) emission from point sources, such as coal fired-power plants, account for the majority of the green houses gasses in the atmosphere. Capture, storage and utilization are required to mitigate adverse environmental effects. Aqueous amine-based CO 2 capture solvents are currently considered the industry standard, but deployment to market is limited by their high regeneration energy demand. In that context, energy efficient and less-viscous water-lean transformational solvent systems known as CO 2 Binding Organic Liquids (CO 2BOLs) are being developed in our group to advance this technology to commercialization. Herein, we present a logical design approachmore » based on fundamental concepts of organic chemistry and computer simulations aimed at lowering solvent viscosity. Conceptually, viscosity reduction would be achieved by systemmatic methods such as introduction of steric hindrance on the anion to minimize the intermolecular cation-anion interactions, fine tuning the electronics, hydrogen bonding orientation and strength, and charge solvation. Conventional standard trial-and-error approaches while effective, are time consuming and economically expensive. Herein, we rethink the metrics and design principles of low-viscosity CO 2 capture solvents using a combined synthesis and computational modeling approach. We critically study the impacts of modyfying factors such as as orientation of hydrogen bonding, introduction of higher degrees of freedom and cation or anion charge solvation and assess if or how each factor impacts viscosity of CO 2BOL CO 2 capture solvents. Ultimately, we found that hydrogen bond orientation and strength is predominantly influencing the viscosity in CO 2BOL solvents. With this knowledge, a new 1-MEIPADM-2-BOL CO 2BOL variant was synthesized and tested, resulting in a solvent that is approximately 60% less viscous at 25 mol% CO 2 loading with respect to our base compound 1-IPADM-2-BOL. The insights gained from the current study redefines the fundamental concepts and understanding of what influences viscosity in concentrated organic CO 2 capture solvents.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kress, Joel David

The development and scale up of cost effective carbon capture processes is of paramount importance to enable the widespread deployment of these technologies to significantly reduce greenhouse gas emissions. The U.S. Department of Energy initiated the Carbon Capture Simulation Initiative (CCSI) in 2011 with the goal of developing a computational toolset that would enable industry to more effectively identify, design, scale up, operate, and optimize promising concepts. The first half of the presentation will introduce the CCSI Toolset consisting of basic data submodels, steady-state and dynamic process models, process optimization and uncertainty quantification tools, an advanced dynamic process control framework,more » and high-resolution filtered computationalfluid- dynamics (CFD) submodels. The second half of the presentation will describe a high-fidelity model of a mesoporous silica supported, polyethylenimine (PEI)-impregnated solid sorbent for CO 2 capture. The sorbent model includes a detailed treatment of transport and amine-CO 2- H 2O interactions based on quantum chemistry calculations. Using a Bayesian approach for uncertainty quantification, we calibrate the sorbent model to Thermogravimetric (TGA) data.« less

Intelligent monitoring system for real-time geologic CO2 storage, optimization and reservoir managemen

NASA Astrophysics Data System (ADS)

Dou, S.; Commer, M.; Ajo Franklin, J. B.; Freifeld, B. M.; Robertson, M.; Wood, T.; McDonald, S.

2017-12-01

Archer Daniels Midland Company's (ADM) world-scale agricultural processing and biofuels production complex located in Decatur, Illinois, is host to two industrial-scale carbon capture and storage projects. The first operation within the Illinois Basin-Decatur Project (IBDP) is a large-scale pilot that injected 1,000,000 metric tons of CO2 over a three year period (2011-2014) in order to validate the Illinois Basin's capacity to permanently store CO2. Injection for the second operation, the Illinois Industrial Carbon Capture and Storage Project (ICCS), started in April 2017, with the purpose of demonstrating the integration of carbon capture and storage (CCS) technology at an ethanol plant. The capacity to store over 1,000,000 metric tons of CO2 per year is anticipated. The latter project is accompanied by the development of an intelligent monitoring system (IMS) that will, among other tasks, perform hydrogeophysical joint analysis of pressure, temperature and seismic reflection data. Using a preliminary radial model assumption, we carry out synthetic joint inversion studies of these data combinations. We validate the history-matching process to be applied to field data once CO2-breakthrough at observation wells occurs. This process will aid the estimation of permeability and porosity for a reservoir model that best matches monitoring observations. The reservoir model will further be used for forecasting studies in order to evaluate different leakage scenarios and develop appropriate early-warning mechanisms. Both the inversion and forecasting studies aim at building an IMS that will use the seismic and pressure-temperature data feeds for providing continuous model calibration and reservoir status updates.

Creating markets for captured carbon: Retrofit of Abbott Power Plant and Future Utilization of Captured CO 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Brien, Kevin C.; Lu, Yongqi; Patel, Vinod

The successful implementation of CCUS requires the confluence of technology, regulatory, and financial factors. One of the factors that impact this confluence is the ability to utilize and monetize captured CO 2. The generally accepted utilization approach has been CO 2-based Enhanced Oil Recovery (EOR), yet this is not always feasible and/or a preferable approach. There is a need to be able to explore a multitude of utilization approaches in order to identify a portfolio of potential utilization mechanisms. This portfolio must be adapted based on the economy of the region. In response to this need, the University of Illinoismore » has formed a Carbon Dioxide Utilization and Reduction (COOULR) Center. The open nature of the university, coupled with a university policy to reduce CO 2 emissions, provides a model for the issues communities will face when attempting to reduce emissions while still maintaining reliable and affordable power. This Center is one of the key steps in the formation of a market for captured CO 2. Furthermore, the goal of the Center is to not only evaluate technologies, but also demonstrate at a large pilot scale how communities may be able to adjust to the need to reduce GHG emissions.« less

Creating markets for captured carbon: Retrofit of Abbott Power Plant and Future Utilization of Captured CO 2

DOE PAGES

O'Brien, Kevin C.; Lu, Yongqi; Patel, Vinod; ...

2017-01-01

The successful implementation of CCUS requires the confluence of technology, regulatory, and financial factors. One of the factors that impact this confluence is the ability to utilize and monetize captured CO 2. The generally accepted utilization approach has been CO 2-based Enhanced Oil Recovery (EOR), yet this is not always feasible and/or a preferable approach. There is a need to be able to explore a multitude of utilization approaches in order to identify a portfolio of potential utilization mechanisms. This portfolio must be adapted based on the economy of the region. In response to this need, the University of Illinoismore » has formed a Carbon Dioxide Utilization and Reduction (COOULR) Center. The open nature of the university, coupled with a university policy to reduce CO 2 emissions, provides a model for the issues communities will face when attempting to reduce emissions while still maintaining reliable and affordable power. This Center is one of the key steps in the formation of a market for captured CO 2. Furthermore, the goal of the Center is to not only evaluate technologies, but also demonstrate at a large pilot scale how communities may be able to adjust to the need to reduce GHG emissions.« less

Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations for solvent-based carbon capture. Part 2: Chemical absorption across a wetted wall column: Original Research Article: Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Xu, Zhijie; Lai, Kevin

Part 1 of this paper presents a numerical model for non-reactive physical mass transfer across a wetted wall column (WWC). In Part 2, we improved the existing computational fluid dynamics (CFD) model to simulate chemical absorption occurring in a WWC as a bench-scale study of solvent-based carbon dioxide (CO2) capture. To generate data for WWC model validation, CO2 mass transfer across a monoethanolamine (MEA) solvent was first measured on a WWC experimental apparatus. The numerical model developed in this work can account for both chemical absorption and desorption of CO2 in MEA. In addition, the overall mass transfer coefficient predictedmore » using traditional/empirical correlations is conducted and compared with CFD prediction results for both steady and wavy falling films. A Bayesian statistical calibration algorithm is adopted to calibrate the reaction rate constants in chemical absorption/desorption of CO2 across a falling film of MEA. The posterior distributions of the two transport properties, i.e., Henry's constant and gas diffusivity in the non-reacting nitrous oxide (N2O)/MEA system obtained from Part 1 of this study, serves as priors for the calibration of CO2 reaction rate constants after using the N2O/CO2 analogy method. The calibrated model can be used to predict the CO2 mass transfer in a WWC for a wider range of operating conditions.« less

Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations for solvent-based carbon capture. Part 2: Chemical absorption across a wetted wall column: Original Research Article: Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations

DOE PAGES

Wang, Chao; Xu, Zhijie; Lai, Kevin; ...

2017-10-24

Part 1 of this paper presents a numerical model for non-reactive physical mass transfer across a wetted wall column (WWC). In Part 2, we improved the existing computational fluid dynamics (CFD) model to simulate chemical absorption occurring in a WWC as a bench-scale study of solvent-based carbon dioxide (CO2) capture. To generate data for WWC model validation, CO2 mass transfer across a monoethanolamine (MEA) solvent was first measured on a WWC experimental apparatus. The numerical model developed in this work can account for both chemical absorption and desorption of CO2 in MEA. In addition, the overall mass transfer coefficient predictedmore » using traditional/empirical correlations is conducted and compared with CFD prediction results for both steady and wavy falling films. A Bayesian statistical calibration algorithm is adopted to calibrate the reaction rate constants in chemical absorption/desorption of CO2 across a falling film of MEA. The posterior distributions of the two transport properties, i.e., Henry's constant and gas diffusivity in the non-reacting nitrous oxide (N2O)/MEA system obtained from Part 1 of this study, serves as priors for the calibration of CO2 reaction rate constants after using the N2O/CO2 analogy method. The calibrated model can be used to predict the CO2 mass transfer in a WWC for a wider range of operating conditions.« less

Modeling Effects of Annealing on Coal Char Reactivity to O 2 and CO 2 , Based on Preparation Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, Troy; Bhat, Sham; Marcy, Peter

Oxy-fired coal combustion is a promising potential carbon capture technology. Predictive computational fluid dynamics (CFD) simulations are valuable tools in evaluating and deploying oxyfuel and other carbon capture technologies, either as retrofit technologies or for new construction. However, accurate predictive combustor simulations require physically realistic submodels with low computational requirements. A recent sensitivity analysis of a detailed char conversion model (Char Conversion Kinetics (CCK)) found thermal annealing to be an extremely sensitive submodel. In the present work, further analysis of the previous annealing model revealed significant disagreement with numerous datasets from experiments performed after that annealing model was developed. Themore » annealing model was accordingly extended to reflect experimentally observed reactivity loss, because of the thermal annealing of a variety of coals under diverse char preparation conditions. The model extension was informed by a Bayesian calibration analysis. In addition, since oxyfuel conditions include extraordinarily high levels of CO 2, the development of a first-ever CO 2 reactivity loss model due to annealing is presented.« less

Modeling Effects of Annealing on Coal Char Reactivity to O 2 and CO 2 , Based on Preparation Conditions

DOE PAGES

Holland, Troy; Bhat, Sham; Marcy, Peter; ...

2017-08-25

Oxy-fired coal combustion is a promising potential carbon capture technology. Predictive computational fluid dynamics (CFD) simulations are valuable tools in evaluating and deploying oxyfuel and other carbon capture technologies, either as retrofit technologies or for new construction. However, accurate predictive combustor simulations require physically realistic submodels with low computational requirements. A recent sensitivity analysis of a detailed char conversion model (Char Conversion Kinetics (CCK)) found thermal annealing to be an extremely sensitive submodel. In the present work, further analysis of the previous annealing model revealed significant disagreement with numerous datasets from experiments performed after that annealing model was developed. Themore » annealing model was accordingly extended to reflect experimentally observed reactivity loss, because of the thermal annealing of a variety of coals under diverse char preparation conditions. The model extension was informed by a Bayesian calibration analysis. In addition, since oxyfuel conditions include extraordinarily high levels of CO 2, the development of a first-ever CO 2 reactivity loss model due to annealing is presented.« less

CFD Simulations of a Regenerative Process for Carbon Dioxide Capture in Advanced Gasification Based Power Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arastoopour, Hamid; Abbasian, Javad

2014-07-31

This project describes the work carried out to prepare a highly reactive and mechanically strong MgO based sorbents and to develop a Population Balance Equations (PBE) approach to describe the evolution of the particle porosity distribution that is linked with Computational Fluid Dynamics (CFD) to perform simulations of the CO2 capture and sorbent regeneration. A large number of MgO-based regenerable sorbents were prepared using low cost and abundant dolomite as the base material. Among various preparation parameters investigated the potassium/magnesium (K/Mg) ratio was identified as the key variable affecting the reactivity and CO2 capacity of the sorbent. The optimum K/Mgmore » ratio is about 0.15. The sorbent formulation HD52-P2 was identified as the “best” sorbent formulation and a large batch (one kg) of the sorbent was prepared for the detailed study. The results of parametric study indicate the optimum carbonation and regeneration temperatures are 360° and 500°C, respectively. The results also indicate that steam has a beneficial effect on the rate of carbonation and regeneration of the sorbent and that the reactivity and capacity of the sorbent decreases in the cycling process (sorbent deactivation). The results indicate that to achieve a high CO2 removal efficiency, the bed of sorbent should be operated at a temperature range of 370-410°C which also favors production of hydrogen through the WGS reaction. To describe the carbonation reaction kinetics of the MgO, the Variable Diffusivity shrinking core Model (VDM) was developed in this project, which was shown to accurately fit the experimental data. An important advantage of this model is that the changes in the sorbent conversion with time can be expressed in an explicit manner, which will significantly reduce the CFD computation time. A Computational Fluid Dynamic/Population Balance Equations (CFD/PBE) model was developed that accounts for the particle (sorbent) porosity distribution and a new version of the method of moments, called Finite size domain Complete set of trial functions Method Of Moments (FCMOM) was used to solve the population balance equations. The PBE model was implemented in a commercial CFD code, Ansys Fluent 13.0. The code was used to test the model in some simple cases and the results were verified against available analytical solution in the literature. Furthermore, the code was used to simulate CO2 capture in a packed-bed and the results were in excellent agreement with the experimental data obtained in the packed bed. The National Energy Laboratory (NETL) Carbon Capture Unit (C2U) design was used in simulate of the hydrodynamics of the cold flow gas/solid system (Clark et al.58). The results indicate that the pressure drop predicted by the model is in good agreement with the experimental data. Furthermore, the model was shown to be able to predict chugging behavior, which was observed during the experiment. The model was used as a base-case for simulations of reactive flow at elevated pressure and temperatures. The results indicate that by controlling the solid circulation rate, up to 70% CO2 removal can be achieved and that the solid hold up in the riser is one of the main factors controlling the extent of CO2 removal. The CFD/PBE simulation model indicates that by using a simulated syngas with a composition of 20% CO2, 20% H2O, 30% CO, and 30% H2, the composition (wet basis) in the reactor outlet corresponded to about 60% CO2 capture with and exit gas containing 65% H2. A preliminary base-case-design was developed for a regenerative MgO-based pre-combustion carbon capture process for a 500 MW IGCC power plant. To minimize the external energy requirement, an extensive heat integration network was developed in Aspen/HYSYS® to produce the steam required in the regenerator and heat integration. In this process, liquid CO2 produced at 50 atm can easily be pumped and sequestered or stored. The preliminary economic analyses indicate that the estimated cost of carbon v capture is in the range of $31-$44/ton, suggesting that a regenerative MgO-Based process can be a viable option for pre-combustion carbon dioxide capture in advanced gasification based power systems.« less

Design of protonation constant measurement apparatus for carbon dioxide capturing solvents

NASA Astrophysics Data System (ADS)

Ma'mun, S.; Amelia, E.; Rahmat, V.; Alwani, D. R.; Kurniawan, D.

2016-11-01

Global warming phenomenon has led to world climate change caused by high concentrations of greenhouse gases (GHG), e.g. carbon dioxide (CO2), in the atmosphere. Carbon dioxide is produced in large amount from coal-fired power plants, iron and steel production, cement production, chemical and petrochemical manufacturing, natural gas purification, and transportation. Carbon dioxide emissions seem to rise from year to year; some efforts to reduce the emissions are, therefore, required. Amine-based absorption could be deployed for post-combustion capture. Some parameters, e.g. mass transfer coefficients and chemical equilibrium constants, are required for a vapor-liquid equilibrium modeling. Protonation constant (pKa), as one of those parameters, could then be measured experimentally. Therefore, an experimental setup to measure pKa of CO2 capturing solvents was designed and validated by measuring the pKa of acetic acid at 30 to 70 °C by a potentiometric titration method. The set up was also used to measure the pKa of MEA at 27 °C. Based on the validation results and due to low vapor pressure of CO2 capturing solvents in general, e.g. alkanolamines, the setup could therefore be used for measuring pKa of the CO2 capturing solvents at temperatures up to 70 °C.

Computational evaluation of metal-organic frameworks for carbon dioxide capture

NASA Astrophysics Data System (ADS)

Yu, Jiamei

Metal-organic frameworks (MOFs), a new class of porous solids comprised of metal-containing nodes linked by organic ligands, have become promising materials for gas separations. In particular, their flexible chemistry makes them attractive for CO2 capture from flue gas streams in post-combustion plants. Although numerous efforts have been exerted on the investigation of MOFs for CO2 capture, the exploration of the effects from coexisting components present in very dilute proportions in flue gases is limited because of the experimental difficulty to determine the coadsorption of CO2 with trace components. In this regard, molecular simulations show superiority. In this study, molecular simulations are used to estimate the influence of impurities: water, O2, and SO2 on post-combustion CO2 capture in MOFs. Firstly, two MOFs with coordinatively unsaturated metal sites (CUMs), HKUST-1 and Mg-MOF-74 are explored. Increase of CO 2 adsorption is observed for hydrated HKUST-1; on the contrary, the opposite water adsorption behavior is observed in hydrated Mg-MOF-74, leading to decrease of CO2 adsorption. Further, water effects on CO 2 capture in M-HKUST1 (M = Mg, Zn, Co, Ni) are evaluated to test whether comparing the binding energy could be a general method to evaluate water effects in MOFs with CUMs. It is found that the method works well for Zn-, Co-, and Ni-HKUST1 but partially for Mg-HKUST1. In addition, the effects of O2 and SO2 on CO2 capture in MOFs are also investigated for the first time, showing that the effects of O2 may be negligible but SO2 has negative effects in the CO 2 capture process in HKUST-1 systems. Secondly, the influences of water on CO2 capture in three UiO-66 MOFs with functional groups, --NH2, --OH and --Br are explored, respectively. For UiO-66-NH2 and -OH, the presence of water lowers CO2 adsorption significantly; in contrast, water shows much smaller effects in UiO-66-Br. Moreover, the presence of SO 2 decreases water adsorption but enhances CO2 uptakes slightly in both UiO-66-NH2 and -Br. Finally, the effects of impurities on CO2 capture in a MOF with suitable pore size (PCN-200) are analyzed. The adsorption of both CO 2 and N2 decrease substantially even with 1% water present in the mixture. In addition, the presence of low SO2 does not show obvious effect in PCN-200. However, a lower CO2 adsorption is observed for a mixture with a high SO2 content. In collaboration with experimental groups, the performances of three new MOFs in CO2 capture are evaluated using molecular simulations. The computational results demonstrate the feasibility of precisely designing single-molecule traps (SMT) for CO2 capture. Also, a multi-functional MOF with micro-porosity, open Cu2+ sites and amine groups has also proved computationally the selective adsorption of CO2 over CH4 and N2. Last, we demonstrate that charge separation is an effective strategy for improving CO2 capture in MOFs.

A preliminary investigation of cryogenic CO2 capture utilizing a reverse Brayton Cycle

NASA Astrophysics Data System (ADS)

Yuan, L. C.; Pfotenhauer, J. M.; Qiu, L. M.

2014-01-01

Utilizing CO2 capture and storage (CCS) technologies is a significant way to reduce carbon emissions from coal fired power plants. Cryogenic CO2 capture (CCC) is an innovative and promising CO2 capture technology, which has an apparent energy and environmental advantage compared to alternatives. A process of capturing CO2 from the flue gas of a coal-fired electrical power plant by cryogenically desublimating CO2 has been discussed and demonstrated theoretically. However, pressurizing the inlet flue gas to reduce the energy penalty for the cryogenic process will lead to a more complex system. In this paper, a modified CCC system utilizing a reverse Brayton Cycle is proposed, and the energy penalty of these two systems are compared theoretically.

Pilot plant studies of the CO{sub 2} capture performance of aqueous MEA and mixed MEA/MDEA solvents at the University of Regina CO{sub 2} capture technology development plant and the Boundary Dam CO{sub 2} capture demonstration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Idem, R.; Wilson, M.; Tontiwachwuthikul, P.

2006-04-12

Evaluations of the benefits of using a mixed MEA/MDEA solvent for CO{sub 2} capture in terms of the heat requirement for solvent regeneration, lean and rich loadings, CO{sub 2} production, and solvent stability were performed by comparing the performance of aqueous 5 kmol/m{sup 3} MEA with that of an aqueous 4:1 molar ratio MEA/MDEA blend of 5 kmol/ml total amine concentration as a function of the operating time. The tests were performed using two pilot CO{sub 2} capture plants of the International Test Centre for CO{sub 2} Capture (ITC), which provided two different sources and compositions of flue gas. Themore » University of Regina CO{sub 2} plant (UR unit) processes flue gas from the combustion of natural gas while the Boundary Dam CO{sub 2} plant (BD unit) processes flue gas from a coal-fired electric power station. The results show that a huge heat-duty reduction can be achieved by using a mixed MEA/MDEA solution instead of a single MEA solution in an industrial environment of a CO{sub 2} capture plant. However, this benefit is dependent on whether the chemical stability of the solvent can be maintained.« less

Bench-scale Development of an Advanced Solid Sorbent-based CO 2 Capture Process for Coal-fired Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, Thomas; Kataria, Atish; Soukri, Mustapha

It is increasingly clear that CO 2 capture and sequestration (CCS) must play a critical role in curbing worldwide CO 2 emissions to the atmosphere. Development of these technologies to cost-effectively remove CO 2 from coal-fired power plants is very important to mitigating the impact these power plants have within the world’s power generation portfolio. Currently, conventional CO 2 capture technologies, such as aqueous-monoethanolamine based solvent systems, are prohibitively expensive and if implemented could result in a 75 to 100% increase in the cost of electricity for consumers worldwide. Solid sorbent CO 2 capture processes – such as RTI’s Advancedmore » Solid Sorbent CO 2, Capture Process – are promising alternatives to conventional, liquid solvents. Supported amine sorbents – of the nature RTI has developed – are particularly attractive due to their high CO 2 loadings, low heat capacities, reduced corrosivity/volatility and the potential to reduce the regeneration energy needed to carry out CO 2 capture. Previous work in this area has failed to adequately address various technology challenges such as sorbent stability and regenerability, sorbent scale-up, improved physical strength and attrition-resistance, proper heat management and temperature control, proper solids handling and circulation control, as well as the proper coupling of process engineering advancements that are tailored for a promising sorbent technology. The remaining challenges for these sorbent processes have provided the framework for the project team’s research and development and target for advancing the technology beyond lab- and bench-scale testing. Under a cooperative agreement with the US Department of Energy, and part of NETL’s CO 2 Capture Program, RTI has led an effort to address and mitigate the challenges associated with solid sorbent CO 2 capture. The overall objective of this project was to mitigate the technical and economic risks associated with the scale-up of solid sorbent-based CO 2 capture processes, enabling subsequent larger pilot demonstrations and ultimately commercial deployment. An integrated development approach has been a key focus of this project in which process development, sorbent development, and economic analyses have informed each of the other development processes. Development efforts have focused on improving the performance stability of sorbent candidates, refining process engineering and design, and evaluating the viability of the technology through detailed economic analyses. Sorbent advancements have led to a next generation, commercially-viable CO 2 capture sorbent exhibiting performance stability in various gas environments and a physically strong fluidizable form. The team has reduced sorbent production costs and optimized the production process and scale-up of PEI-impregnated, fluidizable sorbents. Refinement of the process engineering and design, as well as the construction and operation of a bench-scale research unit has demonstrated promising CO 2 capture performance under simulated coal-fired flue gas conditions. Parametric testing has shown how CO 2 capture performance is impacted by changing process variables, such as Adsorber temperature, Regenerator temperature, superficial flue gas velocity, solids circulation rate, CO 2 partial pressure in the Regenerator, and many others. Long-term testing has generated data for the project team to set the process conditions needed to operate a solids-based system for optimal performance, with continuous 90% CO 2 capture, and no operational interruptions. Data collected from all phases of testing has been used to develop a detailed techno-economic assessment of RTI’s technology. These detailed analyses show that RTI’s technology has significant economic advantages over current amine scrubbing and potential to achieve the DOE’s Carbon Capture Program’s goal of >90% CO 2 capture rate at a cost of < $40/T-CO 2 captured by 2025. Through this integrated technology development approach, the project team has advanced RTI’s CO 2 capture technology to TRL-4 (nearly TRL-5, with the missing variable being testing on actual, coal-fired flue gas), according to the DOE/FE definitions for Technology Readiness Levels. At a broader level, this project has advanced the whole of the solid sorbent CO 2 capture field, with advancements in process engineering and design, technical risk mitigation, sorbent scale-up optimization, and an understanding of the commercial viability and applicability of solid sorbent CO 2 capture technologies for the U.S. existing fleet of coal-fired power plants.« less

SYSTEM LEVEL IMPLICATIONS OF FLEXIBLE CO2 CAPTURE OPERATION

EPA Science Inventory

In ERCOT, turning flexible CO₂ capture systems off during infrequent periods of peak electricity demand can avoid hundreds of millions to billions of dollars in capital costs to replace the power output lost to CO₂ capture energy requirements.  When CO...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Basha, Omar M.; Keller, Murphy J.; Luebke, David R.

The Ionic Liquid (IL) [hmim][Tf 2N] was used as a physical solvent in an Aspen Plus simulation, employing the Peng-Robinson Equation of State (P-R EOS) with Boston-Mathias (BM) alpha function and standard mixing rules, to develop a conceptual process for CO 2 capture from a shifted warm fuel gas stream produced from Pittsburgh # 8 coal for a 400 MWe power plant. The physical properties of the IL, including density, viscosity, surface tension, vapor pressure and heat capacity were obtained from literature and modeled as a function of temperature. Also, available experimental solubility values for CO 2, H 2, Hmore » 2S, CO, and CH 4 in this IL were compiled and their binary interaction parameters (Δ ij and l ij) were optimized and correlated as functions of temperature. The Span-Wager Equation-of-State EOS was also employed to generate CO 2 solubilities in [hmim][Tf 2N] at high pressures (up to 10 MPa) and temperatures (up to 510 K). The conceptual process developed consisted of 4 adiabatic absorbers (2.4 m ID, 30 m high) arranged in parallel and packed with Plastic Pall Rings of 0.025 m for CO 2 capture; 3 flash drums arranged in series for solvent (IL) regeneration with the pressure-swing option; and a pressure-intercooling system for separating and pumping CO 2 up to 153 bar to the sequestration sites. The compositions of all process streams, CO 2 capture efficiency, and net power were calculated using Aspen Plus simulator. The results showed that, based on the composition of the inlet gas stream to the absorbers, 95.67 mol% of CO 2 was captured and sent to sequestration sites; 99.5 mol% of H 2 was separated and sent to turbines; the solvent exhibited a minimum loss of 0.31 mol%; and the net power balance of the entire system was 30.81 MW. These results indicated that [hmim][Tf 2N] IL could be used as a physical solvent for CO 2 capture from warm shifted fuel gas streams with high efficiency.« less

Combined Pressure, Temperature Contrast and Surface-Enhanced Separation of Carbon Dioxide for Post-Combustion Carbon Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhen; Wong, Michael; Gupta, Mayank

The Rice University research team developed a hybrid carbon dioxide (CO 2) absorption process combining absorber and stripper columns using a high surface area ceramic foam gas-liquid contactor for enhanced mass transfer and utilizing waste heat for regeneration. This integrated absorber/desorber arrangement will reduce space requirements, an important factor for retrofitting existing coal-fired power plants with CO 2 capture technology. Described in this report, we performed an initial analysis to estimate the technical and economic feasibility of the process. A one-dimensional (1D) CO 2 absorption column was fabricated to measure the hydrodynamic and mass transfer characteristics of the ceramic foam.more » A bench-scale prototype was constructed to implement the complete CO 2 separation process and tested to study various aspects of fluid flow in the process. A model was developed to simulate the two-dimensional (2D) fluid flow and optimize the CO 2 capture process. Test results were used to develop a final technoeconomic analysis and identify the most appropriate absorbent as well as optimum operating conditions to minimize capital and operating costs. Finally, a technoeconomic study was performed to assess the feasibility of integrating the process into a 600 megawatt electric (MWe) coal-fired power plant. With process optimization, $82/MWh of COE can be achieved using our integrated absorber/desorber CO 2 capture technology, which is very close to DOE's target that no more than a 35% increase in COE with CCS. An environmental, health, and safety (EH&S) assessment of the capture process indicated no significant concern in terms of EH&S effects or legislative compliance.« less

Negative emissions technologies and carbon capture and storage to achieve the Paris Agreement commitments.

PubMed

Haszeldine, R Stuart; Flude, Stephanie; Johnson, Gareth; Scott, Vivian

2018-05-13

How will the global atmosphere and climate be protected? Achieving net-zero CO 2 emissions will require carbon capture and storage (CCS) to reduce current GHG emission rates, and negative emissions technology (NET) to recapture previously emitted greenhouse gases. Delivering NET requires radical cost and regulatory innovation to impact on climate mitigation. Present NET exemplars are few, are at small-scale and not deployable within a decade, with the exception of rock weathering, or direct injection of CO 2 into selected ocean water masses. To keep warming less than 2°C, bioenergy with CCS (BECCS) has been modelled but does not yet exist at industrial scale. CCS already exists in many forms and at low cost. However, CCS has no political drivers to enforce its deployment. We make a new analysis of all global CCS projects and model the build rate out to 2050, deducing this is 100 times too slow. Our projection to 2050 captures just 700 Mt CO 2  yr -1 , not the minimum 6000 Mt CO 2  yr -1 required to meet the 2°C target. Hence new policies are needed to incentivize commercial CCS. A first urgent action for all countries is to commercially assess their CO 2 storage. A second simple action is to assign a Certificate of CO 2 Storage onto producers of fossil carbon, mandating a progressively increasing proportion of CO 2 to be stored. No CCS means no 2°C.This article is part of the theme issue 'The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'. © 2018 The Author(s).

Negative emissions technologies and carbon capture and storage to achieve the Paris Agreement commitments

NASA Astrophysics Data System (ADS)

Haszeldine, R. Stuart; Flude, Stephanie; Johnson, Gareth; Scott, Vivian

2018-05-01

How will the global atmosphere and climate be protected? Achieving net-zero CO2 emissions will require carbon capture and storage (CCS) to reduce current GHG emission rates, and negative emissions technology (NET) to recapture previously emitted greenhouse gases. Delivering NET requires radical cost and regulatory innovation to impact on climate mitigation. Present NET exemplars are few, are at small-scale and not deployable within a decade, with the exception of rock weathering, or direct injection of CO2 into selected ocean water masses. To keep warming less than 2°C, bioenergy with CCS (BECCS) has been modelled but does not yet exist at industrial scale. CCS already exists in many forms and at low cost. However, CCS has no political drivers to enforce its deployment. We make a new analysis of all global CCS projects and model the build rate out to 2050, deducing this is 100 times too slow. Our projection to 2050 captures just 700 Mt CO2 yr-1, not the minimum 6000 Mt CO2 yr-1 required to meet the 2°C target. Hence new policies are needed to incentivize commercial CCS. A first urgent action for all countries is to commercially assess their CO2 storage. A second simple action is to assign a Certificate of CO2 Storage onto producers of fossil carbon, mandating a progressively increasing proportion of CO2 to be stored. No CCS means no 2°C. This article is part of the theme issue `The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'.

A Comparative Study of the CO2 Absorption in Some Solvent-Free Alkanolamines and in Aqueous Monoethanolamine (MEA).

PubMed

Barzagli, Francesco; Mani, Fabrizio; Peruzzini, Maurizio

2016-07-05

The neat secondary amines 2-(methylamino)ethanol, 2-(ethylamino)ethanol, 2-(isopropylamino)ethanol, 2-(benzylamino)ethanol and 2-(butylamino)ethanol react with CO2 at 50-60 °C and room pressure yielding liquid carbonated species without their dilution with any additional solvent. These single-component absorbents have the theoretical CO2 capture capacity of 0.50 (mol CO2/mol amine) due to the formation of the corresponding amine carbamates and protonated amines that were identified by the (13)C NMR analysis. These single-component absorbents were used for CO2 capture (15% and 40% v/v in air) in two series of different procedures: (1) batch experiments aimed at investigating the efficiency and the rate of CO2 capture; (2) continuous cycles of absorption-desorption carried out in packed columns with absorption temperatures brought at 50-60 °C and desorption temperatures at 100-120 °C at room pressure. A number of different amines and experimental setups gave CO2 capture efficiency greater than 90%. For comparison purposes, 30 wt % aqueous MEA was used for CO2 capture under the same operational conditions described for the solvent-free amines. The potential advantages of solvent-free alkanolamines over aqueous MEA in the CO2 capture process were discussed.

Highly Surface-Active Ca(OH)2 Monolayer as a CO2 Capture Material.

PubMed

Özçelik, V Ongun; Gong, Kai; White, Claire E

2018-03-14

Greenhouse gas emissions originating from fossil fuel combustion contribute significantly to global warming, and therefore the design of novel materials that efficiently capture CO 2 can play a crucial role in solving this challenge. Here, we show that reducing the dimensionality of bulk crystalline portlandite results in a stable monolayer material, named portlandene, that is highly effective at capturing CO 2 . On the basis of theoretical analysis comprised of ab initio quantum mechanical calculations and force-field molecular dynamics simulations, we show that this single-layer phase is robust and maintains its stability even at high temperatures. The chemical activity of portlandene is seen to further increase upon defect engineering of its surface using vacancy sites. Defect-containing portlandene is capable of separating CO and CO 2 from a syngas (CO/CO 2 /H 2 ) stream, yet is inert to water vapor. This selective behavior and the associated mechanisms have been elucidated by examining the electronic structure, local charge distribution, and bonding orbitals of portlandene. Additionally, unlike conventional CO 2 capturing technologies, the regeneration process of portlandene does not require high temperature heat treatment because it can release the captured CO 2 by application of a mild external electric field, making portlandene an ideal CO 2 capturing material for both pre- and postcombustion processes.

DEVELOPMENT OF A NOVEL GAS PRESSURIZED STRIPPING (GPS)-BASED TECHNOLOGY FOR CO 2 CAPTURE FROM POST-COMBUSTION FLUE GASES Topical Report: Techno-Economic Analysis of GPS-based Technology for CO 2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Shiaoguo

This topical report presents the techno-economic analysis, conducted by Carbon Capture Scientific, LLC (CCS) and Nexant, for a nominal 550 MWe supercritical pulverized coal (PC) power plant utilizing CCS patented Gas Pressurized Stripping (GPS) technology for post-combustion carbon capture (PCC). Illinois No. 6 coal is used as fuel. Because of the difference in performance between the GPS-based PCC and the MEA-based CO2 absorption technology, the net power output of this plant is not exactly 550 MWe. DOE/NETL Case 11 supercritical PC plant without CO2 capture and Case 12 supercritical PC plant with benchmark MEA-based CO2 capture are chosen as references.more » In order to include CO2 compression process for the baseline case, CCS independently evaluated the generic 30 wt% MEA-based PCC process together with the CO2 compression section. The net power produced in the supercritical PC plant with GPS-based PCC is 647 MW, greater than the MEA-based design. The levelized cost of electricity (LCOE) over a 20-year period is adopted to assess techno-economic performance. The LCOE for the supercritical PC plant with GPS-based PCC, not considering CO2 transport, storage and monitoring (TS&M), is 97.4 mills/kWh, or 152% of the Case 11 supercritical PC plant without CO2 capture, equivalent to $39.6/tonne for the cost of CO2 capture. GPS-based PCC is also significantly superior to the generic MEA-based PCC with CO2 compression section, whose LCOE is as high as 109.6 mills/kWh.« less

Assessing CO2 Mitigation Options Utilizing Detailed Electricity Characteristics and Including Renewable Generation

NASA Astrophysics Data System (ADS)

Bensaida, K.; Alie, Colin; Elkamel, A.; Almansoori, A.

2017-08-01

This paper presents a novel techno-economic optimization model for assessing the effectiveness of CO2 mitigation options for the electricity generation sub-sector that includes renewable energy generation. The optimization problem was formulated as a MINLP model using the GAMS modeling system. The model seeks the minimization of the power generation costs under CO2 emission constraints by dispatching power from low CO2 emission-intensity units. The model considers the detailed operation of the electricity system to effectively assess the performance of GHG mitigation strategies and integrates load balancing, carbon capture and carbon taxes as methods for reducing CO2 emissions. Two case studies are discussed to analyze the benefits and challenges of the CO2 reduction methods in the electricity system. The proposed mitigations options would not only benefit the environment, but they will as well improve the marginal cost of producing energy which represents an advantage for stakeholders.

Reducing the cost of Ca-based direct air capture of CO2.

PubMed

Zeman, Frank

2014-10-07

Direct air capture, the chemical removal of CO2 directly from the atmosphere, may play a role in mitigating future climate risk or form the basis of a sustainable transportation infrastructure. The current discussion is centered on the estimated cost of the technology and its link to "overshoot" trajectories, where atmospheric CO2 levels are actively reduced later in the century. The American Physical Society (APS) published a report, later updated, estimating the cost of a one million tonne CO2 per year air capture facility constructed today that highlights several fundamental concepts of chemical air capture. These fundamentals are viewed through the lens of a chemical process that cycles between removing CO2 from the air and releasing the absorbed CO2 in concentrated form. This work builds on the APS report to investigate the effect of modifications to the air capture system based on suggestions in the report and subsequent publications. The work shows that reduced carbon electricity and plastic packing materials (for the contactor) may have significant effects on the overall price, reducing the APS estimate from $610 to $309/tCO2 avoided. Such a reduction does not challenge postcombustion capture from point sources, estimated at $80/tCO2, but does make air capture a feasible alternative for the transportation sector and a potential negative emissions technology. Furthermore, air capture represents atmospheric reductions rather than simply avoided emissions.

Efficient electrochemical refrigeration power plant using natural gas with ∼100% CO2 capture

NASA Astrophysics Data System (ADS)

Al-musleh, Easa I.; Mallapragada, Dharik S.; Agrawal, Rakesh

2015-01-01

We propose an efficient Natural Gas (NG) based Solid Oxide Fuel Cell (SOFC) power plant equipped with ∼100% CO2 capture. The power plant uses a unique refrigeration based process to capture and liquefy CO2 from the SOFC exhaust. The capture of CO2 is carried out via condensation and purification using two rectifying columns operating at different pressures. The uncondensed gas mixture, comprising of relatively high purity unconverted fuel, is recycled to the SOFC and found to boost the power generation of the SOFC by 22%, when compared to a stand alone SOFC. If Liquefied Natural Gas (LNG) is available at the plant gate, then the refrigeration available from its evaporation is used for CO2 Capture and Liquefaction (CO2CL). If NG is utilized, then a Mixed Refrigerant (MR) vapor compression cycle is utilized for CO2CL. Alternatively, the necessary refrigeration can be supplied by evaporating the captured liquid CO2 at a lower pressure, which is then compressed to supercritical pressures for pipeline transportation. From rigorous simulations, the power generation efficiency of the proposed processes is found to be 70-76% based on lower heating value (LHV). The benefit of the proposed processes is evident when the efficiency of 73% for a conventional SOFC-Gas turbine power plant without CO2 capture is compared with an equivalent efficiency of 71.2% for the proposed process with CO2CL.

Modelling atmospheric oxidation of 2-aminoethanol (MEA) emitted from post-combustion capture using WRF-Chem.

PubMed

Karl, M; Svendby, T; Walker, S-E; Velken, A S; Castell, N; Solberg, S

2015-09-15

Carbon capture and storage (CCS) is a technological solution that can reduce the amount of carbon dioxide (CO2) emissions from the use of fossil fuel in power plants and other industries. A leading method today is amine based post-combustion capture, in which 2-aminoethanol (MEA) is one of the most studied absorption solvents. In this process, amines are released to the atmosphere through evaporation and entrainment from the CO2 absorber column. Modelling is a key instrument for simulating the atmospheric dispersion and chemical transformation of MEA, and for projections of ground-level air concentrations and deposition rates. In this study, the Weather Research and Forecasting model inline coupled with chemistry, WRF-Chem, was applied to quantify the impact of using a comprehensive MEA photo-oxidation sequence compared to using a simplified MEA scheme. Main discrepancies were found for iminoethanol (roughly doubled in the detailed scheme) and 2-nitro aminoethanol, short MEA-nitramine (reduced by factor of two in the detailed scheme). The study indicates that MEA emissions from a full-scale capture plant can modify regional background levels of isocyanic acid. Predicted atmospheric concentrations of isocyanic acid were however below the limit value of 1 ppbv for ambient exposure. The dependence of the formation of hazardous compounds in the OH-initiated oxidation of MEA on ambient level of nitrogen oxides (NOx) was studied in a scenario without NOx emissions from a refinery area in the vicinity of the capture plant. Hourly MEA-nitramine peak concentrations higher than 40 pg m(-3) did only occur when NOx mixing ratios were above 2 ppbv. Therefore, the spatial variability and temporal variability of levels of OH and NOx need to be taken into account in the health risk assessment. The health risk due to direct emissions of nitrosamines and nitramines from full-scale CO2 capture should be investigated in future studies. Copyright © 2015 Elsevier B.V. All rights reserved.

Heteroatom-doped nanoporous carbon derived from MOF-5 for CO2 capture

NASA Astrophysics Data System (ADS)

Ma, Xiancheng; Li, Liqing; Chen, Ruofei; Wang, Chunhao; Li, Hailong; Wang, Shaobin

2018-03-01

Four nanoporous carbons (MUCT) were prepared from metal-organic framework (MOF-5) template and additional carbon source (i.e. urea) by carbonization at different temperatures (600-900 °C). The results showed that specific surface area of four samples was obtained in the range from 1030 to 2307 m2 g-1. By changing the carbonization temperature it can finely tune the pore volume of the MUCT, which having a uniform pore size of around 4.0 nm. With an increasing carbonization temperature, the micropore surface area of MUCT samples varied slightly, but mesopore surface area increased obviously, which had little influence on carbon dioxide (CO2) adsorption capacity. The as-obtained sample MUC900 exhibited the superior CO2 capture capacity of 3.7 mmol g-1 at 0 °C (1 atm). First principle calculations were conducted on carbon models with various functional groups to distinguish heterogeneity and understand carbon surface chemistry for CO2 adsorption. The interaction between CO2 and N-containing functional groups is mainly weak Lewis acid-base interaction. On the other hand, the pyrrole and amine groups show exceptional hydrogen-bonding interaction. The hydroxyls promote the interaction between carbon dioxide and functional groups through hydrogen-bonding interactions and electrostatic potentials, thereby increasing CO2 capture of MUCT.

Engineering and Economic Analysis of an Advanced Ultra-Supercritical Pulverized Coal Power Plant with and without Post-Combustion Carbon Capture Task 7. Design and Economic Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Booras, George; Powers, J.; Riley, C.

2015-09-01

This report evaluates the economics and performance of two A-USC PC power plants; Case 1 is a conventionally configured A-USC PC power plant with superior emission controls, but without CO 2 removal; and Case 2 adds a post-combustion carbon capture (PCC) system to the plant from Case 1, using the design and heat integration strategies from EPRI’s 2015 report, “Best Integrated Coal Plant.” The capture design basis for this case is “partial,” to meet EPA’s proposed New Source Performance Standard, which was initially proposed as 500 kg-CO 2/MWh (gross) or 1100 lb-CO 2/MWh (gross), but modified in August 2015 tomore » 635 kg-CO 2/MWh (gross) or 1400 lb-CO 2/MWh (gross). This report draws upon the collective experience of consortium members, with EPRI and General Electric leading the study. General Electric provided the steam cycle analysis as well as v the steam turbine design and cost estimating. EPRI performed integrated plant performance analysis using EPRI’s PC Cost model.« less

Preliminary Modelling of the Effect of Impurity in CO2 Streams on the Storage Capacity and the Plume Migration in Pohang Basin, Korea

NASA Astrophysics Data System (ADS)

Park, Yongchan; Choi, Byoungyoung; Shinn, Youngjae

2015-04-01

Captured CO2 streams contain various levels of impurities which vary depending on the combustion technology and CO2 sources such as a power plant and iron and steel production processes. Common impurities or contaminants are non-condensable gases like nitrogen, oxygen and hydrogen, and are also air pollutants like sulphur and nitrogen oxides. Specifically for geological storage, the non-condensable gases in CO2 streams are not favourable because they can decrease density of the injected CO2 stream and can affect buoyancy of the plume. However, separation of these impurities to obtain the CO2 purity higher than 99% would greatly increase the cost of capture. In 2010, the Korean Government announced a national framework to develop CCS, with the aim of developing two large scale integrated CCS projects by 2020. In order to achieve this goal, a small scale injection project into Pohang basin near shoreline has begun which is seeking the connection with a capture project, especially at a steel company. Any onshore sites that are suitable for the geological storage are not identified by this time so we turned to the shallow offshore Pohang basin where is close to a large-scale CO2 source. Currently, detailed site surveys are being undertaken and the collected data were used to establish a geological model of the basin. In this study, we performed preliminary modelling study on the effect of impurities on the geological storage using the geological model. Using a potential compositions of impurities in CO2 streams from the steel company, we firstly calculated density and viscosity of CO2 streams as a function of various pressure and temperature conditions with CMG-WINPROP and then investigated the effect of the non-condensable gases on storage capacity, injectivity and plume migrations with CMG-GEM. Further simulations to evaluate the areal and vertical sweep efficiencies by impurities were perform in a 2D vertical cross section as well as in a 3D simulation grid. Also, pressure increases caused by the impurities and the partitioning between CO2 and other non-condensable gases were explored. In addition, the possibility of using these contaminants as a tracer were examined.

Designing Ionic Liquids for CO2 Capture: What’s the role for computation?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brennecke, Joan F.

Presentation on the computational aspects of ionic liquid selection for carbon dioxide capture to the conference attendees at the New Vistas in Molecular Thermodynamics: Experimentation, Molecular Modeling, and Inverse Design, Berkeley, CA, January 7 through 9, 2018

Assessing Atmospheric CO2 Entrapped in Clay Nanotubes using Residual Gas Analyzer.

PubMed

Das, Sankar; Maity, Abhijit; Pradhan, Manik; Jana, Subhra

2016-02-16

A residual gas analyzer (RGA) coupled with a high-vacuum chamber has been explored to measure atmospheric CO2 entrapped in aminosilane-modified clay nanotubes. Ambient CO2 uptake efficacy together with stability of these novel adsorbents composed of both primary and/or secondary amine sites has been demonstrated at standard ambient temperature and pressure. The unprecedented sensitivity and accuracy of the RGA-based mass spectrometry technique toward atmospheric CO2 measurement has been substantiated with a laser-based optical cavity-enhanced integrated cavity output spectroscopy. The adsorption kinetics of atmospheric CO2 on amine-functionalized clay nanotubes followed the fractional-order kinetic model compared to that of the pseudo-first-order or pseudo-second-order rate equations. The efficiency along with stability of these novel adsorbents has also been demonstrated by their repetitive use for CO2 capture in the oxidative environment. Our findings thus point to a fundamental study on the atmospheric CO2 adsorption by amine-loaded adsorbents using an easy handling and low-cost benchtop RGA-based mass spectrometer, opening a new strategy for CO2 capture and sequestering study.

Micromechanical Tests and Geochemical Modeling to Evaluate Evolution of Rock Alteration by CO2-Water Mixtures

NASA Astrophysics Data System (ADS)

Aman, M.; Sun, Y.; Ilgen, A.; Espinoza, N.

2015-12-01

Injection of large volumes of CO2 into geologic formations can help reduce the atmospheric CO2 concentration and lower the impact of burning fossil fuels. However, the injection of CO2 into the subsurface shifts the chemical equilibrium between the mineral assemblage and the pore fluid. This shift will situationally facilitate dissolution and reprecipitation of mineral phases, in particular intergranular cements, and can potentially affect the long term mechanical stability of the host formation. The study of these coupled chemical-mechanical reservoir rock responses can help identify and control unexpected emergent behavior associated with geological CO2 storage.Experiments show that micro-mechanical methods are useful in capturing a variety of mechanical parameters, including Young's modulus, hardness and fracture toughness. In particular, micro-mechanical measurements are well-suited for examining thin altered layers on the surfaces of rock specimens, as well as capturing variability on the scale of lithofacies. We performed indentation and scratching tests on sandstone and siltstone rocks altered in natural CO2-brine environments, as well as on analogous samples altered under high pressure, temperature, and dissolved CO2 conditions in a controlled laboratory experiment. We performed geochemical modeling to support the experimental observations, in particular to gain the insight into mineral dissolution/precipitation as a result of the rock-water-CO2reactions. The comparison of scratch measurements performed on specimens both unaltered and altered by CO2 over geologic time scales results in statistically different values for fracture toughness and scratch hardness, indicating that long term exposure to CO2 caused mechanical degradation of the reservoir rock. Geochemical modeling indicates that major geochemical change caused by CO2 invasion of Entrada sandstone is dissolution of hematite cement, and its replacement with siderite and dolomite during the alteration process.

Jumpstarting commercial-scale CO 2 capture and storage with ethylene production and enhanced oil recovery in the US Gulf

DOE PAGES

Middleton, Richard S.; Levine, Jonathan S.; Bielicki, Jeffrey M.; ...

2015-04-27

CO 2 capture, utilization, and storage (CCUS) technology has yet to be widely deployed at a commercial scale despite multiple high-profile demonstration projects. We suggest that developing a large-scale, visible, and financially viable CCUS network could potentially overcome many barriers to deployment and jumpstart commercial-scale CCUS. To date, substantial effort has focused on technology development to reduce the costs of CO 2 capture from coal-fired power plants. Here, we propose that near-term investment could focus on implementing CO 2 capture on facilities that produce high-value chemicals/products. These facilities can absorb the expected impact of the marginal increase in the costmore » of production on the price of their product, due to the addition of CO 2 capture, more than coal-fired power plants. A financially viable demonstration of a large-scale CCUS network requires offsetting the costs of CO 2 capture by using the CO 2 as an input to the production of market-viable products. As a result, we demonstrate this alternative development path with the example of an integrated CCUS system where CO 2 is captured from ethylene producers and used for enhanced oil recovery in the U.S. Gulf Coast region.« less

Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations for solvent-based carbon capture. Part 2: Chemical absorption across a wetted wall column: Original Research Article: Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Xu, Zhijie; Lai, Kevin

The first part of this paper (Part 1) presents a numerical model for non-reactive physical mass transfer across a wetted wall column (WWC). In Part 2, we improved the existing computational fluid dynamics (CFD) model to simulate chemical absorption occurring in a WWC as a bench-scale study of solvent-based carbon dioxide (CO2) capture. To generate data for WWC model validation, CO2 mass transfer across a monoethanolamine (MEA) solvent was first measured on a WWC experimental apparatus. The numerical model developed in this work has the ability to account for both chemical absorption and desorption of CO2 in MEA. In addition,more » the overall mass transfer coefficient predicted using traditional/empirical correlations is conducted and compared with CFD prediction results for both steady and wavy falling films. A Bayesian statistical calibration algorithm is adopted to calibrate the reaction rate constants in chemical absorption/desorption of CO2 across a falling film of MEA. The posterior distributions of the two transport properties, i.e., Henry’s constant and gas diffusivity in the non-reacting nitrous oxide (N2O)/MEA system obtained from Part 1 of this study, serves as priors for the calibration of CO2 reaction rate constants after using the N2O/CO2 analogy method. The calibrated model can be used to predict the CO2 mass transfer in a WWC for a wider range of operating conditions.« less

Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations for solvent-based carbon capture. Part 2: Chemical absorption across a wetted wall column: Original Research Article: Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Xu, Zhijie; Lai, Kevin

Part 1 of this paper presents a numerical model for non-reactive physical mass transfer across a wetted wall column (WWC). In Part 2, we improved the existing computational fluid dynamics (CFD) model to simulate chemical absorption occurring in a WWC as a bench-scale study of solvent-based carbon dioxide (CO 2) capture. In this study, to generate data for WWC model validation, CO 2 mass transfer across a monoethanolamine (MEA) solvent was first measured on a WWC experimental apparatus. The numerical model developed in this work can account for both chemical absorption and desorption of CO 2 in MEA. In addition,more » the overall mass transfer coefficient predicted using traditional/empirical correlations is conducted and compared with CFD prediction results for both steady and wavy falling films. A Bayesian statistical calibration algorithm is adopted to calibrate the reaction rate constants in chemical absorption/desorption of CO 2 across a falling film of MEA. The posterior distributions of the two transport properties, i.e., Henry's constant and gas diffusivity in the non-reacting nitrous oxide (N 2O)/MEA system obtained from Part 1 of this study, serves as priors for the calibration of CO 2 reaction rate constants after using the N 2O/CO 2 analogy method. Finally, the calibrated model can be used to predict the CO 2 mass transfer in a WWC for a wider range of operating conditions.« less

Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations for solvent-based carbon capture. Part 2: Chemical absorption across a wetted wall column: Original Research Article: Hierarchical calibration and validation framework of bench-scale computational fluid dynamics simulations

DOE PAGES

Wang, Chao; Xu, Zhijie; Lai, Kevin; ...

2017-10-24

Part 1 of this paper presents a numerical model for non-reactive physical mass transfer across a wetted wall column (WWC). In Part 2, we improved the existing computational fluid dynamics (CFD) model to simulate chemical absorption occurring in a WWC as a bench-scale study of solvent-based carbon dioxide (CO 2) capture. In this study, to generate data for WWC model validation, CO 2 mass transfer across a monoethanolamine (MEA) solvent was first measured on a WWC experimental apparatus. The numerical model developed in this work can account for both chemical absorption and desorption of CO 2 in MEA. In addition,more » the overall mass transfer coefficient predicted using traditional/empirical correlations is conducted and compared with CFD prediction results for both steady and wavy falling films. A Bayesian statistical calibration algorithm is adopted to calibrate the reaction rate constants in chemical absorption/desorption of CO 2 across a falling film of MEA. The posterior distributions of the two transport properties, i.e., Henry's constant and gas diffusivity in the non-reacting nitrous oxide (N 2O)/MEA system obtained from Part 1 of this study, serves as priors for the calibration of CO 2 reaction rate constants after using the N 2O/CO 2 analogy method. Finally, the calibrated model can be used to predict the CO 2 mass transfer in a WWC for a wider range of operating conditions.« less

Toward a mechanistic modeling of nitrogen limitation on vegetation dynamics.

PubMed

Xu, Chonggang; Fisher, Rosie; Wullschleger, Stan D; Wilson, Cathy J; Cai, Michael; McDowell, Nate G

2012-01-01

Nitrogen is a dominant regulator of vegetation dynamics, net primary production, and terrestrial carbon cycles; however, most ecosystem models use a rather simplistic relationship between leaf nitrogen content and photosynthetic capacity. Such an approach does not consider how patterns of nitrogen allocation may change with differences in light intensity, growing-season temperature and CO(2) concentration. To account for this known variability in nitrogen-photosynthesis relationships, we develop a mechanistic nitrogen allocation model based on a trade-off of nitrogen allocated between growth and storage, and an optimization of nitrogen allocated among light capture, electron transport, carboxylation, and respiration. The developed model is able to predict the acclimation of photosynthetic capacity to changes in CO(2) concentration, temperature, and radiation when evaluated against published data of V(c,max) (maximum carboxylation rate) and J(max) (maximum electron transport rate). A sensitivity analysis of the model for herbaceous plants, deciduous and evergreen trees implies that elevated CO(2) concentrations lead to lower allocation of nitrogen to carboxylation but higher allocation to storage. Higher growing-season temperatures cause lower allocation of nitrogen to carboxylation, due to higher nitrogen requirements for light capture pigments and for storage. Lower levels of radiation have a much stronger effect on allocation of nitrogen to carboxylation for herbaceous plants than for trees, resulting from higher nitrogen requirements for light capture for herbaceous plants. As far as we know, this is the first model of complete nitrogen allocation that simultaneously considers nitrogen allocation to light capture, electron transport, carboxylation, respiration and storage, and the responses of each to altered environmental conditions. We expect this model could potentially improve our confidence in simulations of carbon-nitrogen interactions and the vegetation feedbacks to climate in Earth system models.

Toward a Mechanistic Modeling of Nitrogen Limitation on Vegetation Dynamics

PubMed Central

Xu, Chonggang; Fisher, Rosie; Wullschleger, Stan D.; Wilson, Cathy J.; Cai, Michael; McDowell, Nate G.

2012-01-01

Nitrogen is a dominant regulator of vegetation dynamics, net primary production, and terrestrial carbon cycles; however, most ecosystem models use a rather simplistic relationship between leaf nitrogen content and photosynthetic capacity. Such an approach does not consider how patterns of nitrogen allocation may change with differences in light intensity, growing-season temperature and CO2 concentration. To account for this known variability in nitrogen-photosynthesis relationships, we develop a mechanistic nitrogen allocation model based on a trade-off of nitrogen allocated between growth and storage, and an optimization of nitrogen allocated among light capture, electron transport, carboxylation, and respiration. The developed model is able to predict the acclimation of photosynthetic capacity to changes in CO2 concentration, temperature, and radiation when evaluated against published data of Vc,max (maximum carboxylation rate) and Jmax (maximum electron transport rate). A sensitivity analysis of the model for herbaceous plants, deciduous and evergreen trees implies that elevated CO2 concentrations lead to lower allocation of nitrogen to carboxylation but higher allocation to storage. Higher growing-season temperatures cause lower allocation of nitrogen to carboxylation, due to higher nitrogen requirements for light capture pigments and for storage. Lower levels of radiation have a much stronger effect on allocation of nitrogen to carboxylation for herbaceous plants than for trees, resulting from higher nitrogen requirements for light capture for herbaceous plants. As far as we know, this is the first model of complete nitrogen allocation that simultaneously considers nitrogen allocation to light capture, electron transport, carboxylation, respiration and storage, and the responses of each to altered environmental conditions. We expect this model could potentially improve our confidence in simulations of carbon-nitrogen interactions and the vegetation feedbacks to climate in Earth system models. PMID:22649564

Light-Triggered CO2 Breathing Foam via Nonsurfactant High Internal Phase Emulsion.

PubMed

Zhang, Shiming; Wang, Dingguan; Pan, Qianhao; Gui, Qinyuan; Liao, Shenglong; Wang, Yapei

2017-10-04

Solid materials for CO 2 capture and storage have attracted enormous attention for gaseous separation, environmental protection, and climate governance. However, their preparation and recovery meet the problems of high energy and financial cost. Herein, a controllable CO 2 capture and storage process is accomplished in an emulsion-templated polymer foam, in which CO 2 is breathed-in under dark and breathed-out under light illumination. Such a process is likely to become a relay of natural CO 2 capture by plants that on the contrary breathe out CO 2 at night. Recyclable CO 2 capture at room temperature and release under light irradiation guarantee its convenient and cost-effective regeneration in industry. Furthermore, CO 2 mixed with CH 4 is successfully separated through this reversible breathing in and out system, which offers great promise for CO 2 enrichment and practical methane purification.

Framing and bias in CO2 capture and storage communication films: Reflections from a CO2 capture and storage research group.

PubMed

Maynard, Carly M; Shackley, Simon

2017-03-01

There has been a growing trend towards incorporating short, educational films as part of research funding and project proposals. Researchers and developers in CO 2 capture and storage are using films to communicate outcomes, but such films can be influenced by experiences and values of the producers. We document the content and presentation of seven online CO 2 capture and storage films to determine how framing occurs and its influence on the tone of films. The core frame presents CO 2 capture and storage as a potential solution to an imminent crisis in climatic warming and lack of a sustainable energy supply. Three subsidiary frames represent CO 2 capture and storage as (1) the only option, (2) a partial option or (3) a scientific curiosity. The results demonstrate that an understanding of the nuanced explicit and implicit messages portrayed by films is essential both for effective framing according to one's intention and for wider public understanding of a field.

MEMBRANE PROCESS TO SEQUESTER CO2 FROM POWER PLANT FLUE GAS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tim Merkel; Karl Amo; Richard Baker

2009-03-31

The objective of this project was to assess the feasibility of using a membrane process to capture CO2 from coal-fired power plant flue gas. During this program, MTR developed a novel membrane (Polaris™) with a CO2 permeance tenfold higher than commercial CO2-selective membranes used in natural gas treatment. The Polaris™ membrane, combined with a process design that uses a portion of combustion air as a sweep stream to generate driving force for CO2 permeation, meets DOE post-combustion CO2 capture targets. Initial studies indicate a CO2 separation and liquefaction cost of $20 - $30/ton CO2 using about 15% of the plantmore » energy at 90% CO2 capture from a coal-fired power plant. Production of the Polaris™ CO2 capture membrane was scaled up with MTR’s commercial casting and coating equipment. Parametric tests of cross-flow and countercurrent/sweep modules prepared from this membrane confirm their near-ideal performance under expected flue gas operating conditions. Commercial-scale, 8-inch diameter modules also show stable performance in field tests treating raw natural gas. These findings suggest that membranes are a viable option for flue gas CO2 capture. The next step will be to conduct a field demonstration treating a realworld power plant flue gas stream. The first such MTR field test will capture 1 ton CO2/day at Arizona Public Service’s Cholla coal-fired power plant, as part of a new DOE NETL funded program.« less

Life cycle assessment of carbon capture and utilization from ammonia process in Mexico.

PubMed

Morales Mora, M A; Vergara, C Pretelín; Leiva, M A; Martínez Delgadillo, S A; Rosa-Domínguez, E R

2016-12-01

Post-combustion CO 2 capture (PCC) of flue gas from an ammonia plant (AP) and the environmental performance of the carbon capture utilization (CCU) technology for greenhouse gas (GHG) emissions to an enhanced oil recovery (EOR) system in Mexico was performed as case study. The process simulations (PS) and life cycle assessment (LCA) were used as supporting tools to quantify the CO 2 capture and their environmental impacts, respectively. Two scenarios were considered: 1) the AP with its shift and CO 2 removal unit and 2) Scenario 1 plus PCC of the flue gas from the AP primary reformer (AP-2CO 2 ) and the global warming (GW) impact. Also, the GW of the whole of a CO 2 -EOR project, from these two streams of captured CO 2 , was evaluated. Results show that 372,426 tCO 2 /year can be PCC from the flue gas of the primary reformer and 480,000 tons/y of capacity from the AP. The energy requirement for solvent regeneration is estimated to be 2.8 MJ/kgCO 2 or a GW impact of 0.22 kgCO 2e /kgCO 2 captured. GW performances are 297.6 kgCO 2e emitted/barrel (bbl) for scenario one, and 106.5 kgCO 2e emitted/bbl for the second. The net emissions, in scenario one, were 0.52 tCO 2e /bbl and 0.33 tCO 2e /bbl in scenario two. Based on PS, this study could be used to evaluate the potential of CO 2 capture of 4080 t/d of 4 ammonia plants. The integration of PS-LCA to a PCC study allows the applicability as methodological framework for the development of a cluster of projects in which of CO 2 could be recycled back to fuel, chemical, petrochemical products or for enhanced oil recovery (EOR). With AP-2CO 2, "CO 2 emission free" ammonia production could be achieved. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Reversed Photosynthesis-like Process for Light-Triggered CO2 Capture, Release, and Conversion.

PubMed

Wang, Dingguan; Liao, Shenglong; Zhang, Shiming; Wang, Yapei

2017-06-22

Materials for CO 2 capture have been extensively exploited for climate governance and gas separation. However, their regeneration is facing the problems of high energy cost and secondary CO 2 contamination. Herein, a reversed photosynthesis-like process is proposed, in which CO 2 is absorbed in darkness while being released under light illumination. The process is likely supplementary to natural photosynthesis of plants, in which, on the contrary, CO 2 is released during the night. Remarkably, the material used here is able to capture 9.6 wt.% CO 2 according to its active component. Repeatable CO 2 capture at room temperature and release under light irradiation ensures its convenient and cost-effective regeneration. Furthermore, CO 2 released from the system is successfully converted into a stable compound in tandem with specific catalysts. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Structures for capturing CO.sub.2, methods of making the structures, and methods of capturing CO.sub.2

DOEpatents

Jones, Christopher W; Hicks, Jason C; Fauth, Daniel J; McMahan, Gray

2012-10-30

Briefly described, embodiments of this disclosure, among others, include carbon dioxide (CO.sub.2) sorption structures, methods of making CO.sub.2 sorption structures, and methods of using CO.sub.2 sorption structures.

Ultrathin graphene oxide-based hollow fiber membranes with brush-like CO2-philic agent for highly efficient CO2 capture.

PubMed

Zhou, Fanglei; Tien, Huynh Ngoc; Xu, Weiwei L; Chen, Jung-Tsai; Liu, Qiuli; Hicks, Ethan; Fathizadeh, Mahdi; Li, Shiguang; Yu, Miao

2017-12-13

Among the current CO 2 capture technologies, membrane gas separation has many inherent advantages over other conventional techniques. However, fabricating gas separation membranes with both high CO 2 permeance and high CO 2 /N 2 selectivity, especially under wet conditions, is a challenge. In this study, sub-20-nm thick, layered graphene oxide (GO)-based hollow fiber membranes with grafted, brush-like CO 2 -philic agent alternating between GO layers are prepared by a facile coating process for highly efficient CO 2 /N 2 separation under wet conditions. Piperazine, as an effective CO 2 -philic agent, is introduced as a carrier-brush into the GO nanochannels with chemical bonding. The membrane exhibits excellent separation performance under simulated flue gas conditions with CO 2 permeance of 1,020 GPU and CO 2 /N 2 selectivity as high as 680, demonstrating its potential for CO 2 capture from flue gas. We expect this GO-based membrane structure combined with the facile coating process to facilitate the development of ultrathin GO-based membranes for CO 2 capture.

Imidazolium salt-modified porous hypercrosslinked polymers for synergistic CO2 capture and conversion.

PubMed

Wang, Jinquan; Sng, Waihong; Yi, Guangshun; Zhang, Yugen

2015-08-04

A new type of imidazolium salt-modified porous hypercrosslinked polymer (BET surface area up to 926 m(2) g(-1)) was reported. These porous materials exhibited good CO2 capture capacities (14.5 wt%) and catalytic activities for the conversion of CO2 into various cyclic carbonates under metal-free conditions. The synergistic effect of CO2 capture and conversion was observed.

Atmospheric CO2 capture by algae: Negative carbon dioxide emission path.

PubMed

Moreira, Diana; Pires, José C M

2016-09-01

Carbon dioxide is one of the most important greenhouse gas, which concentration increase in the atmosphere is associated to climate change and global warming. Besides CO2 capture in large emission point sources, the capture of this pollutant from atmosphere may be required due to significant contribution of diffuse sources. The technologies that remove CO2 from atmosphere (creating a negative balance of CO2) are called negative emission technologies. Bioenergy with Carbon Capture and Storage may play an important role for CO2 mitigation. It represents the combination of bioenergy production and carbon capture and storage, keeping carbon dioxide in geological reservoirs. Algae have a high potential as the source of biomass, as they present high photosynthetic efficiencies and high biomass yields. Their biomass has a wide range of applications, which can improve the economic viability of the process. Thus, this paper aims to assess the atmospheric CO2 capture by algal cultures. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dual phase high-temperature membranes for CO2 separation - performance assessment in post- and pre-combustion processes.

PubMed

Anantharaman, Rahul; Peters, Thijs; Xing, Wen; Fontaine, Marie-Laure; Bredesen, Rune

2016-10-20

Dual phase membranes are highly CO 2 -selective membranes with an operating temperature above 400 °C. The focus of this work is to quantify the potential of dual phase membranes in pre- and post-combustion CO 2 capture processes. The process evaluations show that the dual phase membranes integrated with an NGCC power plant for CO 2 capture are not competitive with the MEA process for post-combustion capture. However, dual phase membrane concepts outperform the reference Selexol technology for pre-combustion CO 2 capture in an IGCC process. The two processes evaluated in this work, post-combustion NGCC and pre-combustion IGCC, represent extremes in CO 2 partial pressure fed to the separation unit. Based on the evaluations it is expected that dual phase membranes could be competitive for post-combustion capture from a pulverized coal fired power plant (PCC) and pre-combustion capture from an Integrated Reforming Cycle (IRCC).

Development of a Carbon Management Geographic Information System (GIS) for the United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howard Herzog; Holly Javedan

In this project a Carbon Management Geographical Information System (GIS) for the US was developed. The GIS stored, integrated, and manipulated information relating to the components of carbon management systems. Additionally, the GIS was used to interpret and analyze the effect of developing these systems. This report documents the key deliverables from the project: (1) Carbon Management Geographical Information System (GIS) Documentation; (2) Stationary CO{sub 2} Source Database; (3) Regulatory Data for CCS in United States; (4) CO{sub 2} Capture Cost Estimation; (5) CO{sub 2} Storage Capacity Tools; (6) CO{sub 2} Injection Cost Modeling; (7) CO{sub 2} Pipeline Transport Costmore » Estimation; (8) CO{sub 2} Source-Sink Matching Algorithm; and (9) CO{sub 2} Pipeline Transport and Cost Model.« less

Low Cost, High Capacity Regenerable Sorbent for Carbon Dioxide Capture from Existing Coal-fired Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alptekin, Gokhan; Jayaraman, Ambalavanan; Dietz, Steven

In this project TDA Research, Inc (TDA) has developed a new post combustion carbon capture technology based on a vacuum swing adsorption system that uses a steam purge and demonstrated its technical feasibility and economic viability in laboratory-scale tests and tests in actual coal derived flue gas. TDA uses an advanced physical adsorbent to selectively remove CO 2 from the flue gas. The sorbent exhibits a much higher affinity for CO 2 than N 2, H 2O or O 2, enabling effective CO 2 separation from the flue gas. We also carried out a detailed process design and analysis ofmore » the new system as part of both sub-critical and super-critical pulverized coal fired power plants. The new technology uses a low cost, high capacity adsorbent that selectively removes CO 2 in the presence of moisture at the flue gas temperature without a need for significant cooling of the flue gas or moisture removal. The sorbent is based on a TDA proprietary mesoporous carbon that consists of surface functionalized groups that remove CO 2 via physical adsorption. The high surface area and favorable porosity of the sorbent also provides a unique platform to introduce additional functionality, such as active groups to remove trace metals (e.g., Hg, As). In collaboration with the Advanced Power and Energy Program of the University of California, Irvine (UCI), TDA developed system simulation models using Aspen PlusTM simulation software to assess the economic viability of TDA’s VSA-based post-combustion carbon capture technology. The levelized cost of electricity including the TS&M costs for CO 2 is calculated as $116.71/MWh and $113.76/MWh for TDA system integrated with sub-critical and super-critical pulverized coal fired power plants; much lower than the $153.03/MWhand $147.44/MWh calculated for the corresponding amine based systems. The cost of CO 2 captured for TDA’s VSA based system is $38.90 and $39.71 per tonne compared to $65.46 and $66.56 per tonne for amine based system on 2011 $ basis, providing 40% lower cost of CO 2 captured. In this analysis we have used a sorbent life of 4 years. If a longer sorbent life can be maintained (which is not unreasonable for fixed bed commercial PSA systems), this would lower the cost of CO 2 captured by $0.05 per tonne (e.g., to $38.85 and $39.66 per tonne at 5 years sorbent replacement). These system analysis results suggest that TDA’s VSA-based post-combustion capture technology can substantially improve the power plant’s thermal performance while achieving near zero emissions, including greater than 90% carbon capture. The higher net plant efficiency and lower capital and operating costs results in a substantial reduction in the cost of carbon capture and cost of electricity for the power plant equipped with TDA’s technology.« less

Response surface method for modeling the removal of carbon dioxide from a simulated gas using water absorption enhanced with a liquid-film-forming device.

PubMed

Nguyen, Diem-Mai Kim; Imai, Tsuyoshi; Dang, Thanh-Loc Thi; Kanno, Ariyo; Higuchi, Takaya; Yamamoto, Koichi; Sekine, Masahiko

2018-03-01

This paper presents the results from using a physical absorption process to absorb gaseous CO 2 mixed with N 2 using water by producing tiny bubbles via a liquid-film-forming device (LFFD) that improves the solubility of CO 2 in water. The influence of various parameters-pressure, initial CO 2 concentration, gas-to-liquid ratios, and temperature-on the CO 2 removal efficiency and its absorption rate in water were investigated and estimated thoroughly by statistical polynomial models obtained by the utilization of the response surface method (RSM) with a central composite design (CCD). Based on the analysis, a high efficiency of CO 2 capture can be reached in conditions such as low pressure, high CO 2 concentration at the inlet, low gas/liquid ratio, and low temperature. For instance, the highest removal efficiency in the RSM-CCD experimental matrix of nearly 80% occurred for run number 20, which was conducted at 0.30MPa, CO 2 concentration of 35%, gas/liquid ratio of 0.71, and temperature of 15°C. Furthermore, the coefficients of determination, R 2 , were 0.996 for the removal rate and 0.982 for the absorption rate, implying that the predicted values computed by the constructed models correlate strongly and fit well with the experimental values. The results obtained provide essential information for implementing this method properly and effectively and contribute a promising approach to the problem of CO 2 capture in air pollution treatment. Copyright © 2017. Published by Elsevier B.V.

An Integrated, Low Temperature Process to Capture and Sequester Carbon Dioxide from Industrial Emissions

NASA Astrophysics Data System (ADS)

Wendlandt, R. F.; Foremski, J. J.

2013-12-01

Laboratory experiments show that it is possible to integrate (1) the chemistry of serpentine dissolution, (2) capture of CO2 gas from the combustion of natural gas and coal-fired power plants using aqueous amine-based solvents, (3) long-term CO2 sequestration via solid phase carbonate precipitation, and (4) capture solvent regeneration with acid recycling in a single, continuous process. In our process, magnesium is released from serpentine at 300°C via heat treatment with ammonium sulfate salts or at temperatures as low as 50°C via reaction with sulfuric acid. We have also demonstrated that various solid carbonate phases can be precipitated directly from aqueous amine-based (NH3, MEA, DMEA) CO2 capture solvent solutions at room temperature. Direct precipitation from the capture solvent enables regenerating CO2 capture solvent without the need for heat and without the need to compress the CO2 off gas. We propose that known low-temperature electrochemical methods can be integrated with this process to regenerate the aqueous amine capture solvent and recycle acid for dissolution of magnesium-bearing mineral feedstocks and magnesium release. Although the direct precipitation of magnesite at ambient conditions remains elusive, experimental results demonstrate that at temperatures ranging from 20°C to 60°C, either nesquehonite Mg(HCO3)(OH)●2H2O or a double salt with the formula [NH4]2Mg(CO3)2●4H2O or an amorphous magnesium carbonate precipitate directly from the capture solvent. These phases are less desirable for CO2 sequestration than magnesite because they potentially remove constituents (water, ammonia) from the reaction system, reducing the overall efficiency of the sequestration process. Accordingly, the integrated process can be accomplished with minimal energy consumption and loss of CO2 capture and acid solvents, and a net generation of 1 to 4 moles of H2O/6 moles of CO2 sequestered (depending on the solid carbonate precipitate and amount of produced H2 and O2 gas reacted to produce heat and water). Features of the integrated process include the following: 1) the four separate processes have compatible chemistry, enabling design of an integrated, continuous process scheme for CO2 capture and sequestration; 2) all 4 stages of the process can be conducted at ambient or slightly elevated temperatures; 3) precipitating carbonate directly from the capture solvent eliminates the need for costly CO2 gas compression; and 4) recycling the acid used for serpentine dissolution and the solvent used for CO2 capture reduces feed stock costs.

Capture-ready power plants - options, technologies and economics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bohm, M.C.

2006-06-15

A plant can be considered to be capture-ready if at some point in the future it can be retrofitted for carbon capture and sequestration and still be economical to operate. The first part of the thesis outlines the two major designs that are being considered for construction in the near-term - pulverized coal (PC) and integrated gasification/combined cycle (IGCC). It details the steps that are necessary to retrofit each of these plants for CO{sub 2} capture and sequestration and assesses the steps that can be taken to reduce the costs and output de-rating of the plant after a retrofit. The second part of the thesis evaluates the lifetime (40 year) net present value (NPV) costs of plants with differing levels of pre-investment for CO{sub 2} capture. Three scenarios are evaluated - a baseline supercritical PC plant, a baseline IGCC plant and an IGCC plant with pre-investment for capture. The results of this thesis show that a baseline PC plant is the most economical choice under low CO{sub 2} tax rates, and IGCC plants are preferable at higher tax rates. The third part of this thesis evaluates the concept of CO{sub 2} 'lock-in'. CO{sub 2} lock-in occurs when a newly built plant is so prohibitively expensive to retrofit for CO{sub 2} capture that it will never be retrofitted for capture, and offers no economic opportunity to reduce the CO{sub 2} emissions from the plant, besides shutting down or rebuilding. The results show that IGCC plants are expected to have lower lifetime CO{sub 2} emissions than a PC plant, given moderate (10-35more » $$/ton CO{sub 2}) initial tax rates. Higher 4 (above $$40) or lower (below $7) initial tax rates do not result in significant differences in lifetime CO{sub 2} emissions from these plants. Little difference is seen in the lifetime CO{sub 2} emissions between the IGCC plants with and without pre-investment for CO{sub 2} capture. 32 refs., 22 figs., 20 tabs., 1 app.« less

A process for capturing CO 2 from the atmosphere

DOE PAGES

Keith, David W.; Holmes, Geoffrey; St. Angelo, David; ...

2018-06-07

Here, we describe a process for capturing CO 2 from the atmosphere in an industrial plant. The design captures ~1 Mt-CO 2/year in a continuous process using an aqueous KOH sorbent coupled to a calcium caustic recovery loop. We describe the design rationale, summarize performance of the major unit operations, and provide a capital cost breakdown developed with an independent consulting engineering firm. We report results from a pilot plant which provides data on performance of the major unit operations. We summarize the energy and material balance computed using an Aspen process simulation. When CO 2 is delivered at 15more » MPa the design requires either 8.81 GJ of natural gas, or 5.25 GJ of gas and 366 kWhr of electricity, per ton of CO 2 captured. Depending on financial assumptions, energy costs, and the specific choice of inputs and outputs, the levelized cost per ton CO 2 captured from the atmosphere ranges from 94 to 232 $/t-CO 2.« less

CO 2 Capture from Ambient Air by Crystallization with a Guanidine Sorbent

DOE PAGES

Seipp, Charles A.; Univ. of Texas, Austin, TX; Williams, Neil J.; ...

2016-12-21

Carbon capture and storage is an important strategy for stabilizing the increasing concentration of atmospheric CO 2 and the global temperature. A possible approach toward reversing this trend and decreasing the atmospheric CO 2 concentration is to remove the CO 2 directly from air (direct air capture). In this paper, we report a simple aqueous guanidine sorbent that captures CO 2 from ambient air and binds it as a crystalline carbonate salt by guanidinium hydrogen bonding. The resulting solid has very low aqueous solubility (K sp=1.0(4)×10 -8), which facilitates its separation from solution by filtration. The bound CO 2 canmore » be released by relatively mild heating of the crystals at 80–120 °C, which regenerates the guanidine sorbent quantitatively. Finally and thus, this crystallization-based approach to CO 2 separation from air requires minimal energy and chemical input, and offers the prospect for low-cost direct air capture technologies.« less

A process for capturing CO 2 from the atmosphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keith, David W.; Holmes, Geoffrey; St. Angelo, David

Here, we describe a process for capturing CO 2 from the atmosphere in an industrial plant. The design captures ~1 Mt-CO 2/year in a continuous process using an aqueous KOH sorbent coupled to a calcium caustic recovery loop. We describe the design rationale, summarize performance of the major unit operations, and provide a capital cost breakdown developed with an independent consulting engineering firm. We report results from a pilot plant which provides data on performance of the major unit operations. We summarize the energy and material balance computed using an Aspen process simulation. When CO 2 is delivered at 15more » MPa the design requires either 8.81 GJ of natural gas, or 5.25 GJ of gas and 366 kWhr of electricity, per ton of CO 2 captured. Depending on financial assumptions, energy costs, and the specific choice of inputs and outputs, the levelized cost per ton CO 2 captured from the atmosphere ranges from 94 to 232 $/t-CO 2.« less

Computational designing and screening of solid materials for CO2capture

NASA Astrophysics Data System (ADS)

Duan, Yuhua

In this presentation, we will update our progress on computational designing and screening of solid materials for CO2 capture. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO2 sorbent candidates from the vast array of possible solid materials have been proposed and validated at NETL. The advantage of this method is that it identifies the thermodynamic properties of the CO2 capture reaction as a function of temperature and pressure without any experimental input beyond crystallographic structural information of the solid phases involved. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO2 adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO2 capture reactions by the solids of interest, we were able to identify only those solid materials for which lower capture energy costs are expected at the desired working conditions. In addition, we present a simulation scheme to increase and decrease the turnover temperature (Tt) of solid capturing CO2 reaction by mixing other solids. Our results also show that some solid sorbents can serve as bi-functional materials: CO2 sorbent and CO oxidation catalyst. Such dual functionality could be used for removing both CO and CO2 after water-gas-shift to obtain pure H2.

PNNL Report on the Development of Bench-scale CFD Simulations for Gas Absorption across a Wetted Wall Column

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Xu, Zhijie; Lai, Canhai

This report is prepared for the demonstration of hierarchical prediction of carbon capture efficiency of a solvent-based absorption column. A computational fluid dynamics (CFD) model is first developed to simulate the core phenomena of solvent-based carbon capture, i.e., the CO2 physical absorption and chemical reaction, on a simplified geometry of wetted wall column (WWC) at bench scale. Aqueous solutions of ethanolamine (MEA) are commonly selected as a CO2 stream scrubbing liquid. CO2 is captured by both physical and chemical absorption using highly CO2 soluble and reactive solvent, MEA, during the scrubbing process. In order to provide confidence bound on themore » computational predictions of this complex engineering system, a hierarchical calibration and validation framework is proposed. The overall goal of this effort is to provide a mechanism-based predictive framework with confidence bound for overall mass transfer coefficient of the wetted wall column (WWC) with statistical analyses of the corresponding WWC experiments with increasing physical complexity.« less

Methanol from CO2 by organo-cocatalysis: CO2 capture and hydrogenation in one process step.

PubMed

Reller, Christian; Pöge, Matthias; Lißner, Andreas; Mertens, Florian O R L

2014-12-16

Carbon dioxide chemically bound to alcohol-amines was hydrogenated to methanol under retrieval of these industrially used CO2 capturing reagents. The energetics of the process can be seen as a partial cancellation of the exothermic heat of reaction of the hydrogenation with the endothermic one of the CO2 release from the capturing reagent. The process provides a means to significantly improve the energy efficiency of CO2 to methanol conversions.

CO 2 capture from IGCC gas streams using the AC-ABC process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagar, Anoop; McLaughlin, Elisabeth; Hornbostel, Marc

The objective of this project was to develop a novel, low-cost CO 2 capture process from pre-combustion gas streams. The bench-scale work was conducted at the SRI International. A 0.15-MWe integrated pilot plant was constructed and operated for over 700 hours at the National Carbon Capture Center, Wilsonville, AL. The AC-ABC (ammonium carbonate-ammonium bicarbonate) process for capture of CO 2 and H 2S from the pre-combustion gas stream offers many advantages over Selexol-based technology. The process relies on the simple chemistry of the NH 3-CO 2-H 2O-H 2S system and on the ability of the aqueous ammoniated solution to absorbmore » CO 2 at near ambient temperatures and to release it as a high-purity, high-pressure gas at a moderately elevated regeneration temperature. It is estimated the increase in cost of electricity (COE) with the AC-ABC process will be ~ 30%, and the cost of CO 2 captured is projected to be less than $27/metric ton of CO 2 while meeting 90% CO 2 capture goal. The Bechtel Pressure Swing Claus (BPSC) is a complementary technology offered by Bechtel Hydrocarbon Technology Solutions, Inc. BPSC is a high-pressure, sub-dew-point Claus process that allows for nearly complete removal of H 2S from a gas stream. It operates at gasifier pressures and moderate temperatures and does not affect CO 2 content. When coupled with AC-ABC, the combined technologies allow a nearly pure CO 2 stream to be captured at high pressure, something which Selexol and other solvent-based technologies cannot achieve.« less

Design of Stratified Functional Nanoporous Materials for CO 2 Capture and Conversion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, J. Karl; Ye, Jingyun

The objective of this project is to develop novel nanoporous materials for CO 2 capture and conversion. The motivation of this work is that capture of CO 2 from flue gas or the atmosphere coupled with catalytic hydrogenation of CO 2 into valuable chemicals and fuels can reduce the net amount of CO 2 in the atmosphere while providing liquid transportation fuels and other commodity chemicals. One approach to increasing the economic viability of carbon capture and conversion is to design a single material that can be used for both the capture and catalytic conversion of CO 2, because suchmore » a material could increase efficiency through process intensification. We have used density functional theory (DFT) methods to design catalytic moieties that can be incorporated into various metal organic framework (MOF) materials. We chose to work with MOFs because they are highly tailorable, can be functionalized, and have been shown to selectively adsorb CO 2 over N 2, which is a requirement for CO 2 capture from flue gas. Moreover, the incorporation of molecular catalytic moieties into MOF, through covalent bonding, produces a heterogeneous catalytic material having activities and selectivities close to those of homogeneous catalysts, but without the draw-backs associated with homogeneous catalysis.« less

Membrane Process to Capture CO{sub 2} from Coal-Fired Power Plant Flue Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Merkel, Tim; Wei, Xiaotong; Firat, Bilgen

2012-03-31

This final report describes work conducted for the U.S. Department of Energy National Energy Technology Laboratory (DOE NETL) on development of an efficient membrane process to capture carbon dioxide (CO{sub 2}) from power plant flue gas (award number DE-NT0005312). The primary goal of this research program was to demonstrate, in a field test, the ability of a membrane process to capture up to 90% of CO{sub 2} in coal-fired flue gas, and to evaluate the potential of a full-scale version of the process to perform this separation with less than a 35% increase in the levelized cost of electricity (LCOE).more » Membrane Technology and Research (MTR) conducted this project in collaboration with Arizona Public Services (APS), who hosted a membrane field test at their Cholla coal-fired power plant, and the Electric Power Research Institute (EPRI) and WorleyParsons (WP), who performed a comparative cost analysis of the proposed membrane CO{sub 2} capture process. The work conducted for this project included membrane and module development, slipstream testing of commercial-sized modules with natural gas and coal-fired flue gas, process design optimization, and a detailed systems and cost analysis of a membrane retrofit to a commercial power plant. The Polaris? membrane developed over a number of years by MTR represents a step-change improvement in CO{sub 2} permeance compared to previous commercial CO{sub 2}-selective membranes. During this project, membrane optimization work resulted in a further doubling of the CO{sub 2} permeance of Polaris membrane while maintaining the CO{sub 2}/N{sub 2} selectivity. This is an important accomplishment because increased CO{sub 2} permeance directly impacts the membrane skid cost and footprint: a doubling of CO{sub 2} permeance halves the skid cost and footprint. In addition to providing high CO{sub 2} permeance, flue gas CO{sub 2} capture membranes must be stable in the presence of contaminants including SO{sub 2}. Laboratory tests showed no degradation in Polaris membrane performance during two months of continuous operation in a simulated flue gas environment containing up to 1,000 ppm SO{sub 2}. A successful slipstream field test at the APS Cholla power plant was conducted with commercialsize Polaris modules during this project. This field test is the first demonstration of stable performance by commercial-sized membrane modules treating actual coal-fired power plant flue gas. Process design studies show that selective recycle of CO{sub 2} using a countercurrent membrane module with air as a sweep stream can double the concentration of CO{sub 2} in coal flue gas with little energy input. This pre-concentration of CO{sub 2} by the sweep membrane reduces the minimum energy of CO{sub 2} separation in the capture unit by up to 40% for coal flue gas. Variations of this design may be even more promising for CO{sub 2} capture from NGCC flue gas, in which the CO{sub 2} concentration can be increased from 4% to 20% by selective sweep recycle. EPRI and WP conducted a systems and cost analysis of a base case MTR membrane CO{sub 2} capture system retrofitted to the AEP Conesville Unit 5 boiler. Some of the key findings from this study and a sensitivity analysis performed by MTR include: The MTR membrane process can capture 90% of the CO{sub 2} in coal flue gas and produce high-purity CO{sub 2} (>99%) ready for sequestration. CO{sub 2} recycle to the boiler appears feasible with minimal impact on boiler performance; however, further study by a boiler OEM is recommended. For a membrane process built today using a combination of slight feed compression, permeate vacuum, and current compression equipment costs, the membrane capture process can be competitive with the base case MEA process at 90% CO{sub 2} capture from a coal-fired power plant. The incremental LCOE for the base case membrane process is about equal to that of a base case MEA process, within the uncertainty in the analysis. With advanced membranes (5,000 gpu for CO{sub 2} and 50 for CO{sub 2}/N{sub 2}), operating with no feed compression and low-cost CO{sub 2} compression equipment, an incremental LCOE of $33/MWh at 90% capture can be achieved (40% lower than the advanced MEA case). Even with lower cost compression, it appears unlikely that a membrane process using high feed compression (>5 bar) can be competitive with amine absorption, due to the capital cost and energy consumption of this equipment. Similarly, low vacuum pressure (<0.2 bar) cannot be used due to poor efficiency and high cost of this equipment. High membrane permeance is important to reduce the capital cost and footprint of the membrane unit. CO{sub 2}/N{sub 2} selectivity is less important because it is too costly to generate a pressure ratio where high selectivity can be useful. A potential cost ?sweet spot? exists for use of membrane-based technology, if 50-70% CO{sub 2} capture is acceptable. There is a minimum in the cost of CO{sub 2} avoided/ton that membranes can deliver at 60% CO{sub 2} capture, which is 20% lower than the cost at 90% capture. Membranes operating with no feed compression are best suited for lower capture rates. Currently, it appears that the biggest hurdle to use of membranes for post-combustion CO{sub 2} capture is compression equipment cost. An alternative approach is to use sweep membranes in parallel with another CO{sub 2} capture technology that does not require feed compression or vacuum equipment. Hybrid designs that utilize sweep membranes for selective CO{sub 2} recycle show potential to significantly reduce the minimum energy of CO{sub 2} separation.« less

CO2 Accounting and Risk Analysis for CO2 Sequestration at Enhanced Oil Recovery Sites.

PubMed

Dai, Zhenxue; Viswanathan, Hari; Middleton, Richard; Pan, Feng; Ampomah, William; Yang, Changbing; Jia, Wei; Xiao, Ting; Lee, Si-Yong; McPherson, Brian; Balch, Robert; Grigg, Reid; White, Mark

2016-07-19

Using CO2 in enhanced oil recovery (CO2-EOR) is a promising technology for emissions management because CO2-EOR can dramatically reduce sequestration costs in the absence of emissions policies that include incentives for carbon capture and storage. This study develops a multiscale statistical framework to perform CO2 accounting and risk analysis in an EOR environment at the Farnsworth Unit (FWU), Texas. A set of geostatistical-based Monte Carlo simulations of CO2-oil/gas-water flow and transport in the Morrow formation are conducted for global sensitivity and statistical analysis of the major risk metrics: CO2/water injection/production rates, cumulative net CO2 storage, cumulative oil/gas productions, and CO2 breakthrough time. The median and confidence intervals are estimated for quantifying uncertainty ranges of the risk metrics. A response-surface-based economic model has been derived to calculate the CO2-EOR profitability for the FWU site with a current oil price, which suggests that approximately 31% of the 1000 realizations can be profitable. If government carbon-tax credits are available, or the oil price goes up or CO2 capture and operating expenses reduce, more realizations would be profitable. The results from this study provide valuable insights for understanding CO2 storage potential and the corresponding environmental and economic risks of commercial-scale CO2-sequestration in depleted reservoirs.

Encapsulation of Ionic Liquids with an Aprotic Heterocyclic Anion (AHA-IL) for CO2 Capture: Preserving the Favorable Thermodynamics and Enhancing the Kinetics of Absorption.

PubMed

Moya, Cristian; Alonso-Morales, Noelia; de Riva, Juan; Morales-Collazo, Oscar; Brennecke, Joan F; Palomar, Jose

2018-03-08

The performance of an ionic liquid with an aprotic heterocyclic anion (AHA-IL), trihexyl(tetradecyl)phosphonium 2-cyanopyrrolide ([P 66614 ][2-CNPyr]), for CO 2 capture has been evaluated considering both the thermodynamics and the kinetics of the phenomena. Absorption gravimetric measurements of the gas-liquid equilibrium isotherms of CO 2 -AHA-IL systems were carried out from 298 to 333 K and at pressures up to 15 bar, analyzing the role of both chemical and physical absorption phenomena in the overall CO 2 solubility in the AHA-IL, as has been done previously. In addition, the kinetics of the CO 2 chemical absorption process was evaluated by in situ Fourier transform infrared spectroscopy-attenuated total reflection, following the characteristic vibrational signals of the reactants and products over the reaction time. A chemical absorption model was used to describe the time-dependent concentration of species involved in the reactive absorption, obtaining kinetic parameters (such as chemical reaction kinetic constants and diffusion coefficients) as a function of temperatures and pressures. As expected, the results demonstrate that the CO 2 absorption rate is mass-transfer-controlled because of the relatively high viscosity of AHA-IL. The AHA-IL was encapsulated in a porous carbon sphere (Encapsulated Ionic Liquid, ENIL) to improve the kinetic performance of the AHA-IL for CO 2 capture. The newly synthesized AHA-ENIL material was evaluated as a CO 2 sorbent with gravimetric absorption measurements. AHA-ENIL systems preserve the good CO 2 absorption capacity of the AHA-IL but drastically enhance the CO 2 absorption rate because of the increased gas-liquid surface contact area achieved by solvent encapsulation.

CO 2 Capture by Cold Membrane Operation with Actual Power Plant Flue Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chaubey, Trapti; Kulkarni, Sudhir; Hasse, David

The main objective of the project was to develop a post-combustion CO 2 capture process based on the hybrid cold temperature membrane operation. The CO 2 in the flue gas from coal fired power plant is pre-concentrated to >60% CO 2 in the first stage membrane operation followed by further liquefaction of permeate stream to achieve >99% CO 2 purity. The aim of the project was based on DOE program goal of 90% CO 2 capture with >95% CO 2 purity from Pulverized Coal (PC) fired power plants with $40/tonne of carbon capture cost by 2025. The project moves themore » technology from TRL 4 to TRL 5. The project involved optimization of Air Liquide commercial 12” PI-1 bundle to improve the bundle productivity by >30% compared to the previous baseline (DE-FE0004278) using computational fluid dynamics (CFD) modeling and bundle testing with synthetic flue gas at 0.1 MWe bench scale skid located at Delaware Research and Technology Center (DRTC). In parallel, the next generation polyimide based novel PI-2 membrane was developed with 10 times CO 2 permeance compared to the commercial PI-1 membrane. The novel PI-2 membrane was scaled from mini-permeator to 1” permeator and 1” bundle for testing. Bundle development was conducted with a Development Spin Unit (DSU) installed at MEDAL. Air Liquide’s cold membrane technology was demonstrated with real coal fired flue gas at the National Carbon Capture Center (NCCC) with a 0.3 MWe field-test unit (FTU). The FTU was designed to incorporate testing of two PI-1 commercial membrane bundles (12” or 6” diameter) in parallel or series. A slip stream was sent to the next generation PI-2 membrane for testing with real flue gas. The system exceeded performance targets with stable PI-1 membrane operation for over 500 hours of single bundle, steady state testing. The 12” PI-1 bundle exceeded the productivity target by achieving ~600 Nm3/hr, where the target was set at ~455 Nm3/hr at 90% capture rate. The cost of 90% CO 2 capture from a 550 MWe net coal power plant was estimated between 40 and $45/tonne. A 6” PI-1 bundle exhibited superior bundle performance compared to the 12” PI-1 bundle. However, the carbon capture cost was not lower with the 6” PI-1 bundle due to the higher bundle installed cost. A 1” PI-1 bundle was tested to compare bundles with different length / diameter ratios. This bundle exhibited the lowest performance due to the different fiber winding pattern and increased bundle non-ideality. Several long-term and parametric tests were conducted with 3,200 hours of total run-time at NCCC. Finally, the new PI-2 membrane fiber was tested at a small scale (1” modules) in real flue gas and exhibited up to 10 times the CO 2 permeance and slightly lower CO 2/N 2 selectivity as the commercial PI-1 fiber. This corresponded to a projected 4 - 5 times increase in the productivity per bundle and a potential cost reduction of $3/tonne for CO2 capture, as compared with PI-1. An analytical campaign was conducted to trace different impurities such as NOx, mercury, Arsenic, Selenium in gas and liquid samples through the carbon capture system. An Environmental, Health and Safety (EH&S) analysis was completed to estimate emissions from a 550 MWe net power plant with carbon capture using cold membrane. A preliminary design and cost analysis was completed for 550 tpd (~25 MWe) plant to assess the capital investment and carbon capture cost for PI-1 and PI-2 membrane solutions from coal fired flue gas. A comparison was made with an amine based solution with significant cost advantage for the membrane at this scale. Additional preliminary design and cost analysis was completed between coal, natural gas and SMR flue gas for carbon capture at 550 tpd (~25 MWe) plant.« less

Phase-Change Aminopyridines as Carbon Dioxide Capture Solvents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malhotra, Deepika; Page, Jordan P.; Bowden, Mark E.

Carbon dioxide is the main atmospheric greenhouse gas released from industrial point sources. In order to mitigate adverse environmental effects of these emissions, carbon capture, storage and utilization is required. To this end, several CO2 capture technologies are being developed for application in carbon capture, which include aqueous amines and water-lean solvents. Herein we report new aminopyridine solvents with the potential for CO2 capture from coal-fired power plants. These four solvents 2-picolylamine, 3-picolylamine, 4-picolylamine and N’-(pyridin-4-ylmethyl)ethane-1,2-diamine are liquids that rapidly bind CO2 to form crystalline solids at standard room temperature and pressure. These solvents have displayed high CO2 capture capacitymore » (11 - 20 wt%) and can be regenerated at temperatures in the range of 120 - 150 C. The advantage of these primary aminopyridine solvents is that crystalline salt product can be separated, making it possible to regenerate only the CO2-rich solid ultimately resulting in reduced energy penalty.« less

Development of Novel Carbon Sorbents for CO{sub 2} Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishnan, Gopala; Hornbostel, Marc; Bao, Jianer

2013-11-30

An innovative, low-cost, and low-energy-consuming carbon dioxide (CO{sub 2}) capture technology was developed, based on CO{sub 2}adsorption on a high-capacity and durable carbon sorbent. This report describes the (1) performance of the concept on a bench-scale system; (2) results of parametric tests to determine the optimum operating conditions; (3) results of the testing with a flue gas from coal-fired boilers; and (4) evaluation of the technical and economic viability of the technology. The process uses a falling bed of carbon sorbent microbeads to separate the flue gas into two streams: a CO{sub 2} -lean flue gas stream from which >more » 90% of the CP{sub 2} is removed and a pure stream of CO{sub 2} that is ready for compression and sequestration. The carbo sorbent microbeads have several unique properties such as high CO{sub 2} capacity, low heat of adsorption and desorption (25 to 28 kJ/mole), mechanically robust, and rapid adsorption and desorption rates. The capture of CO{sub 2} from the flue gas is performed at near ambient temperatures in whic the sorbent microbeads flow down by gravity counter-current with the up-flow of the flue gas. The adsorbed CO{sub 2} is stripped by heating the CO{sub 2}-loaded sorbent to - 100°C, in contact with low-pressure (- 5 psig) steam in a section at the bottom of the adsorber. The regenerated sorben is dehydrated of adsorbed moisture, cooled, and lifted back to the adsorber. The CO{sub 2} from the desorber is essentially pure and can be dehydrated, compressed, and transported to a sequestration site. Bench-scale tests using a simulated flue gas showed that the integrated system can be operated to provide > 90% CO{sub 2} capture from a 15% CO{sub 2} stream in the adsorber and produce > 98% CO{sub 2} at the outlet of the stripper. Long-term tests ( 1,000 cycles) showed that the system can be operated reliably without sorbent agglomeration or attrition. The bench-scale reactor was also operated using a flue gas stream from a coal-fired boil at the University of Toledo campus for about 135 h, comprising 7,000 cycles of adsorption and desorption using the desulfurized flue gas that contained only 4.5% v/v CO{sub 2}. A capture efficiency of 85 to 95% CO{sub 2} was achieved under steady-state conditi ons. The CO{sub 2} adsorption capacity did not change significantly during the field test, as determined from the CO{sub 2} adsorptio isotherms of fresh and used sorbents. The process is also being tested using the flue gas from a PC-fired power plant at the National Carbon Capture Center (NCCC), Wilsonville, AL. The cost of electricity was calculated for CO{sub 2} capture using the carbon sorbent and compared with the no-CO{sub 2} capture and CO{sub 2} capture with an amine-based system. The increase i the levelized cost of electricity (L-COE) is about 37% for CO{sub 2} capture using the carbon sorbent in comparison to 80% for an amine-based system, demonstrating the economic advantage of C capture using the carbon sorbent. The 37% increase in the L-COE corresponds to a cost of capture of $30/ton of CO{sub 2}, including compression costs, capital cost for the capture system, and increased plant operating and capital costs to make up for reduced plant efficiency. Preliminary sensitivity analyses showed capital costs, pressure drops in the adsorber, and steam requirement for the regenerator are the major variables in determining the cost of CO{sub 2} capture. The results indicate that further long-term testing with a flue gas from a pulverized coal­ fired boiler should be performed to obtain additional data relating to the effects of flue gas contaminants, the ability to reduce pressure drop by using alternate structural packing , and the use of low-cost construction materials.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Middleton, Richard S.; Levine, Jonathan S.; Bielicki, Jeffrey M.

CO 2 capture, utilization, and storage (CCUS) technology has yet to be widely deployed at a commercial scale despite multiple high-profile demonstration projects. We suggest that developing a large-scale, visible, and financially viable CCUS network could potentially overcome many barriers to deployment and jumpstart commercial-scale CCUS. To date, substantial effort has focused on technology development to reduce the costs of CO 2 capture from coal-fired power plants. Here, we propose that near-term investment could focus on implementing CO 2 capture on facilities that produce high-value chemicals/products. These facilities can absorb the expected impact of the marginal increase in the costmore » of production on the price of their product, due to the addition of CO 2 capture, more than coal-fired power plants. A financially viable demonstration of a large-scale CCUS network requires offsetting the costs of CO 2 capture by using the CO 2 as an input to the production of market-viable products. As a result, we demonstrate this alternative development path with the example of an integrated CCUS system where CO 2 is captured from ethylene producers and used for enhanced oil recovery in the U.S. Gulf Coast region.« less

CO2 Capture by Absorption with Potassium Carbonate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gary T. Rochelle; Eric Chen; Babatunde Oyenekan

The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Ethylenediamine was detected in a degraded solution of MEA/PZ solution, suggesting that piperazine is subject to oxidation. Stripper modeling has demonstrated that vacuum strippers will be more energy efficient if constructed short and fat rather than tall and skinny. The matrix stripper has been identified as a configuration that will significantly reduce energy use. Extensive measurements of CO{sub 2} solubility in 7 m MEA at 40 and 60 C have confirmedmore » the work by Jou and Mather. Corrosion of carbon steel without inhibitors increases from 19 to 181 mpy in lean solutions of 6.2 m MEA/PZ as piperazine increases from 0 to 3.1 m.« less

Investigation of CO2 capture mechanisms of liquid-like nanoparticle organic hybrid materials via structural characterization.

PubMed

Park, Youngjune; Decatur, John; Lin, Kun-Yi Andrew; Park, Ah-Hyung Alissa

2011-10-28

Nanoparticle organic hybrid materials (NOHMs) have been recently developed that comprise an oligomeric or polymeric canopy tethered to surface-modified nanoparticles via ionic or covalent bonds. It has already been shown that the tunable nature of the grafted polymeric canopy allows for enhanced CO(2) capture capacity and selectivity via the enthalpic intermolecular interactions between CO(2) and the task-specific functional groups, such as amines. Interestingly, for the same amount of CO(2) loading NOHMs have also exhibited significantly different swelling behavior compared to that of the corresponding polymers, indicating a potential structural effect during CO(2) capture. If the frustrated canopy species favor spontaneous ordering due to steric and/or entropic effects, the inorganic cores of NOHMs could be organized into unusual structural arrangements. Likewise, the introduction of small gaseous molecules such as CO(2) could reduce the free energy of the frustrated canopy. This entropic effect, the result of unique structural nature, could allow NOHMs to capture CO(2) more effectively. In order to isolate the entropic effect, NOHMs were synthesized without the task-specific functional groups. The relationship between their structural conformation and the underlying mechanisms for the CO(2) absorption behavior were investigated by employing NMR and ATR FT-IR spectroscopies. The results provide fundamental information needed for evaluating and developing novel liquid-like CO(2) capture materials and give useful insights for designing and synthesizing NOHMs for more effective CO(2) capture. This journal is © the Owner Societies 2011

Reassessing the Efficiency Penalty from Carbon Capture in Coal-Fired Power Plants.

PubMed

Supekar, Sarang D; Skerlos, Steven J

2015-10-20

This paper examines thermal efficiency penalties and greenhouse gas as well as other pollutant emissions associated with pulverized coal (PC) power plants equipped with postcombustion CO2 capture for carbon sequestration. We find that, depending on the source of heat used to meet the steam requirements in the capture unit, retrofitting a PC power plant that maintains its gross power output (compared to a PC power plant without a capture unit) can cause a drop in plant thermal efficiency of 11.3-22.9%-points. This estimate for efficiency penalty is significantly higher than literature values and corresponds to an increase of about 5.3-7.7 US¢/kWh in the levelized cost of electricity (COE) over the 8.4 US¢/kWh COE value for PC plants without CO2 capture. The results follow from the inclusion of mass and energy feedbacks in PC power plants with CO2 capture into previous analyses, as well as including potential quality considerations for safe and reliable transportation and sequestration of CO2. We conclude that PC power plants with CO2 capture are likely to remain less competitive than natural gas combined cycle (without CO2 capture) and on-shore wind power plants, both from a levelized and marginal COE point of view.

A HIERARCHICAL MODELING FRAMEWORK FOR GEOLOGICAL STORAGE OF CARBON DIOXIDE

EPA Science Inventory

Carbon Capture and Storage, or CCS, is likely to be an important technology in a carbonconstrained world. CCS will involve subsurface injection of massive amounts of captured CO₂, on a scale that has not previously been approached. The unprecedented scale of t...

The urgency of the development of CO2 capture from ambient air

PubMed Central

Lackner, Klaus S.; Brennan, Sarah; Matter, Jürg M.; Park, A.-H. Alissa; Wright, Allen; van der Zwaan, Bob

2012-01-01

CO2 capture and storage (CCS) has the potential to develop into an important tool to address climate change. Given society’s present reliance on fossil fuels, widespread adoption of CCS appears indispensable for meeting stringent climate targets. We argue that for conventional CCS to become a successful climate mitigation technology—which by necessity has to operate on a large scale—it may need to be complemented with air capture, removing CO2 directly from the atmosphere. Air capture of CO2 could act as insurance against CO2 leaking from storage and furthermore may provide an option for dealing with emissions from mobile dispersed sources such as automobiles and airplanes. PMID:22843674

Carbon dioxide capture from a cement manufacturing process

DOEpatents

Blount, Gerald C [North Augusta, SC; Falta, Ronald W [Seneca, SC; Siddall, Alvin A [Aiken, SC

2011-07-12

A process of manufacturing cement clinker is provided in which a clean supply of CO.sub.2 gas may be captured. The process also involves using an open loop conversion of CaO/MgO from a calciner to capture CO.sub.2 from combustion flue gases thereby forming CaCO.sub.3/CaMg(CO.sub.3).sub.2. The CaCO.sub.3/CaMg(CO.sub.3).sub.2 is then returned to the calciner where CO.sub.2 gas is evolved. The evolved CO.sub.2 gas, along with other evolved CO.sub.2 gases from the calciner are removed from the calciner. The reactants (CaO/MgO) are feed to a high temperature calciner for control of the clinker production composition.

Improving ecophysiological simulation models to predict the impact of elevated atmospheric CO2 concentration on crop productivity

PubMed Central

Yin, Xinyou

2013-01-01

Background Process-based ecophysiological crop models are pivotal in assessing responses of crop productivity and designing strategies of adaptation to climate change. Most existing crop models generally over-estimate the effect of elevated atmospheric [CO2], despite decades of experimental research on crop growth response to [CO2]. Analysis A review of the literature indicates that the quantitative relationships for a number of traits, once expressed as a function of internal plant nitrogen status, are altered little by the elevated [CO2]. A model incorporating these nitrogen-based functional relationships and mechanisms simulated photosynthetic acclimation to elevated [CO2], thereby reducing the chance of over-estimating crop response to [CO2]. Robust crop models to have small parameterization requirements and yet generate phenotypic plasticity under changing environmental conditions need to capture the carbon–nitrogen interactions during crop growth. Conclusions The performance of the improved models depends little on the type of the experimental facilities used to obtain data for parameterization, and allows accurate projections of the impact of elevated [CO2] and other climatic variables on crop productivity. PMID:23388883

Oxidatively-Stable Linear Poly(propylenimine)-Containing Adsorbents for CO2 Capture from Ultra-Dilute Streams.

PubMed

Pang, Simon H; Lively, Ryan P; Jones, Christopher W

2018-05-29

Aminopolymer-based solid sorbents have been widely investigated for CO2 capture from dilute streams such as flue gas or ambient air. However, the oxidative stability of the most well-studied aminopolymer, poly(ethylenimine) (PEI), is limited, causing it to lose its CO2 capture capacity after exposure to oxygen at elevated temperatures. Here we demonstrate the use of linear poly(propylenimine) (PPI), synthesized via a simple cationic ring-opening polymerization, as a more oxidatively-stable alternative to PEI with high CO2 capacity and amine efficiency. The performance of linear PPI/SBA-15 composites is investigated over a range of CO2 capture conditions (CO2 partial pressure, adsorption temperature) to examine the trade-off between adsorption capacity and sorption site accessibility, which may be expected to be more limited in linear polymers relative to the prototypical hyperbranched PEI. Linear PPI/SBA-15 composites are more efficient at CO2 capture and retain 65-83% of their CO2 capacity after exposure to a harsh oxidative treatment, compared to 20-40% retention for linear PEI. Additionally, we demonstrate long-term stability of linear PPI sorbents over 50 adsorption/desorption cycles with no loss in performance. Combined with other strategies for improving oxidative stability and adsorption kinetics, linear PPI may play a role as a component of stable, solid adsorbents in commercial applications for CO2 capture. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electrochemical Capture and Release of CO2 in Aqueous Electrolytes Using an Organic Semiconductor Electrode

PubMed Central

2017-01-01

Developing efficient methods for capture and controlled release of carbon dioxide is crucial to any carbon capture and utilization technology. Herein we present an approach using an organic semiconductor electrode to electrochemically capture dissolved CO2 in aqueous electrolytes. The process relies on electrochemical reduction of a thin film of a naphthalene bisimide derivative, 2,7-bis(4-(2-(2-ethylhexyl)thiazol-4-yl)phenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone (NBIT). This molecule is specifically tailored to afford one-electron reversible and one-electron quasi-reversible reduction in aqueous conditions while not dissolving or degrading. The reduced NBIT reacts with CO2 to form a stable semicarbonate salt, which can be subsequently oxidized electrochemically to release CO2. The semicarbonate structure is confirmed by in situ IR spectroelectrochemistry. This process of capturing and releasing carbon dioxide can be realized in an oxygen-free environment under ambient pressure and temperature, with uptake efficiency for CO2 capture of ∼2.3 mmol g–1. This is on par with the best solution-phase amine chemical capture technologies available today. PMID:28378994

Bench-Scale Silicone Process for Low-Cost CO{sub 2} Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wood, Benjamin; Genovese, Sarah; Perry, Robert

2013-12-31

A bench-scale system was designed and built to test an aminosilicone-based solvent. A model was built of the bench-scale system and this model was scaled up to model the performance of a carbon capture unit, using aminosilicones, for CO{sub 2} capture and sequestration (CCS) for a pulverized coal (PC) boiler at 550 MW. System and economic analysis for the carbon capture unit demonstrates that the aminosilicone solvent has significant advantages relative to a monoethanol amine (MEA)-based system. The CCS energy penalty for MEA is 35.9% and the energy penalty for aminosilicone solvent is 30.4% using a steam temperature of 395more » °C (743 °F). If the steam temperature is lowered to 204 °C (400 °F), the energy penalty for the aminosilicone solvent is reduced to 29%. The increase in cost of electricity (COE) over the non-capture case for MEA is ~109% and increase in COE for aminosilicone solvent is ~98 to 103% depending on the solvent cost at a steam temperature of 395 °C (743 °F). If the steam temperature is lowered to 204 °C (400 °F), the increase in COE for the aminosilicone solvent is reduced to ~95-100%.« less

Modeling of sonochemistry in water in the presence of dissolved carbon dioxide.

PubMed

Authier, Olivier; Ouhabaz, Hind; Bedogni, Stefano

2018-07-01

CO 2 capture and utilization (CCU) is a process that captures CO 2 emissions from sources such as fossil fuel power plants and reuses them so that they will not enter the atmosphere. Among the various ways of recycling CO 2 , reduction reactions are extensively studied at lab-scale. However, CO 2 reduction by standard methods is difficult. Sonochemistry may be used in CO 2 gas mixtures bubbled through water subjected to ultrasound waves. Indeed, the sonochemical reduction of CO 2 in water has been already investigated by some authors, showing that fuel species (CO and H 2 ) are obtained in the final products. The aim of this work is to model, for a single bubble, the close coupling of the mechanisms of bubble dynamics with the kinetics of gas phase reactions in the bubble that can lead to CO 2 reduction. An estimation of time-scales is used to define the controlling steps and consequently to solve a reduced model. The calculation of the concentration of free radicals and gases formed in the bubble is undertaken over many cycles to look at the effects of ultrasound frequency, pressure amplitude, initial bubble radius and bubble composition in CO 2 . The strong effect of bubble composition on the CO 2 reduction rate is confirmed in accordance with experimental data from the literature. When the initial fraction of CO 2 in the bubble is low, bubble growth and collapse are slightly modified with respect to simulation without CO 2 , and chemical reactions leading to CO 2 reduction are promoted. However, the peak collapse temperature depends on the thermal properties of the CO 2 and greatly decreases as the CO 2 increases in the bubble. The model shows that initial bubble radius, ultrasound frequency and pressure amplitude play a critical role in CO 2 reduction. Hence, in the case of a bubble with an initial radius of around 5 μm, CO 2 reduction appears to be more favorable at a frequency around 300 kHz than at a low frequency of around 20 kHz. Finally, the industrial application of ultrasound to CO 2 reduction in water would be largely dependent on sonochemical efficiency. Under the conditions tested, this process does not seem to be sufficiently efficient. Copyright © 2018 Elsevier B.V. All rights reserved.

Method and system for capturing carbon dioxide and/or sulfur dioxide from gas stream

DOEpatents

Chang, Shih-Ger; Li, Yang; Zhao, Xinglei

2014-07-08

The present invention provides a system for capturing CO.sub.2 and/or SO.sub.2, comprising: (a) a CO.sub.2 and/or SO.sub.2 absorber comprising an amine and/or amino acid salt capable of absorbing the CO.sub.2 and/or SO.sub.2 to produce a CO.sub.2- and/or SO.sub.2-containing solution; (b) an amine regenerator to regenerate the amine and/or amino acid salt; and, when the system captures CO.sub.2, (c) an alkali metal carbonate regenerator comprising an ammonium catalyst capable catalyzing the aqueous alkali metal bicarbonate into the alkali metal carbonate and CO.sub.2 gas. The present invention also provides for a system for capturing SO.sub.2, comprising: (a) a SO.sub.2 absorber comprising aqueous alkali metal carbonate, wherein the alkali metal carbonate is capable of absorbing the SO.sub.2 to produce an alkali metal sulfite/sulfate precipitate and CO.sub.2.

Thermodynamic and mass transfer modeling of carbon dioxide absorption into aqueous 2-amino-2-methyl-1-propanol

DOE PAGES

Sherman, Brent J.; Rochelle, Gary T.

2016-12-16

Explanations for the mass transfer behavior of 2-amino-2-methyl-1-propanol (AMP) are conflicting, despite extensive study of the amine for CO 2 capture. At equilibrium, aqueous AMP reacts with CO 2 to give bicarbonate in a 1:1 ratio. While this is the same stoichiometry as a tertiary amine, the reaction rate of AMP is 100 times faster. This work aims to explain the mass transfer behavior of AMP, specifically the stoichiometry and kinetics. An eNRTL thermodynamic model was used to regress wetted-wall column mass transfer data with two activity-based reactions: formation of carbamate and formation of bicarbonate. Data spanned 40–100 C andmore » 0.15–0.60 mol CO 2/mol alk). The fitted carbamate rate constant is three orders of magnitude greater than the bicarbonate rate constant. Rapid carbamate formation explains the kinetics, while the stoichiometry is explained by the carbamate reverting in the bulk liquid to allow CO 2 to form bicarbonate. Understanding the role of carbamate formation and diffusion in hindered amines enables optimizing solvent amine concentration by balancing viscosity and free amine concentration. Furthermore, this improves absorber design for CO 2 capture.« less

Theoretical calculating the thermodynamic properties of solid sorbents for CO{sub 2} capture applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duan, Yuhua

2012-11-02

Since current technologies for capturing CO{sub 2} to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO{sub 2} reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO{sub 2} capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO{sub 2} sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculatedmore » thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO{sub 2} adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO{sub 2} capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO{sub 2} sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO{sub 2} capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we first introduce our screening methodology and the results on a testing set of solids with known thermodynamic properties to validate our methodology. Then, by applying our computational method to several different kinds of solid systems, we demonstrate that our methodology can predict the useful information to help developing CO{sub 2} capture Technologies.« less

Emerging materials for lowering atmospheric carbon

DOE PAGES

Barkakaty, Balaka; Sumpter, Bobby G.; Ivanov, Ilia N.; ...

2016-12-08

CO 2 emissions from anthropogenic sources and the rate at which they increase could have deep global ramifications such as irreversible climate change and increased natural disasters. Because greater than 50% of anthropogenic CO 2 emissions come from small, distributed sectors such as homes, offices, and transportation sources, most renewable energy systems and on-site carbon capture technologies for reducing future CO 2 emissions cannot be effectively utilized. This problem might be mediated by considering novel materials and technologies for directly capturing/removing CO 2 from air. But, compared to materials for capturing CO 2 at on-site emission sources, materials for capturingmore » CO 2 directly from air must be more selective to CO 2, and should operate and be stable at near ambient conditions. Here, we briefly summarize the recent developments in materials for capturing carbon dioxide directly from air. Furthermore, we discuss the challenges in this field and offer a perspective for developing the current state-of-art and also highlight the potential of a few recent discoveries in materials science that show potential for advanced application of air capture technology.« less

Hydrogen sulfide capture by limestone and dolomite at elevated pressure. 2: Sorbent particle conversion modeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zevenhoven, C.A.P.; Yrjas, K.P.; Hupa, M.M.

1996-03-01

The physical structure of a limestone or dolomite to be used in in-bed sulfur capture in fluidized bed gasifiers has a great impact on the efficiency of sulfur capture and sorbent use. In this study an unreacted shrinking core model with variable effective diffusivity is applied to sulfidation test data from a pressurized thermogravimetric apparatus (P-TGA) for a set of physically and chemically different limestone and dolomite samples. The particle size was 250--300 {micro}m for all sorbents, which were characterized by chemical composition analysis, particle density measurement, mercury porosimetry, and BET internal surface measurement. Tests were done under typical conditionsmore » for a pressurized fluidized-bed gasifier, i.e., 20% CO{sub 2}, 950 C, 20 bar. At these conditions the limestone remains uncalcined, while the dolomite is half-calcined. Additional tests were done at low CO{sub 2} partial pressures, yielding calcined limestone and fully calcined dolomite. The generalized model allows for determination of values for the initial reaction rate and product layer diffusivity.« less

Enabling CCS via Low-temperature Geothermal Energy Integration for Fossil-fired Power Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davidson, Casie L.; Heldebrant, D. J.; Bearden, M. D.

Here, among the key barriers to commercial scale deployment is the cost associated with CO 2 capture. This is particularly true for existing large, fossil-fired assets that account for a large fraction of the electricity generation fleet in developed nations, including the U.S. Fitting conventional combustion technologies with CO 2 capture systems can carry an energy penalty of thirty percent or more, resulting in an increased price of power to the grid, as well as an overall decrease in net plant output. Taken together with the positive growth in demand for electricity, this implies a need for accelerated capital build-outmore » in the power generation markets to accommodate both demand growth and decreased output at retrofitted plants. In this paper, the authors present the results of a study to assess the potential to use geothermal energy to provide boiler feedwater preheating, capturing efficiency improvements designed to offset the losses associated with CO 2 capture. Based on NETL benchmark cases and subsequent analysis of the application using site-specific data from the North Valmy power plant, several cases for CO 2 capture were evaluated. These included geothermally assisted MEA capture, CO2BOLs capture, and stand-alone hybrid power generation, compared with a baseline, no-geothermal case. Based on Case 10, and assuming 2.7 MMlb/h of geothermally sourced 150 ºC water, the parasitic power load associated with MEA capture could be offset by roughly seven percent, resulting in a small (~1 percent) overall loss to net power generation, but at levelized costs of electricity similar to the no-geothermal CCS case. For the CO 2BOLs case, the availability of 150°C geothermal fluid could allow the facility to not only offset the net power decrease associated with CO 2BOLs capture alone, but could increase nameplate capacity by two percent. The geothermally coupled CO 2BOLs case also decreases LCOE by 0.75 ¢/kWh relative to the non-hybrid CO 2BOLs case, with the improved performance over the MEA case driven by the lower regeneration temperature and associated duty for CO 2BOLs relative to MEA.« less

Enabling CCS via Low-temperature Geothermal Energy Integration for Fossil-fired Power Generation

DOE PAGES

Davidson, Casie L.; Heldebrant, D. J.; Bearden, M. D.; ...

2017-08-18

Here, among the key barriers to commercial scale deployment is the cost associated with CO 2 capture. This is particularly true for existing large, fossil-fired assets that account for a large fraction of the electricity generation fleet in developed nations, including the U.S. Fitting conventional combustion technologies with CO 2 capture systems can carry an energy penalty of thirty percent or more, resulting in an increased price of power to the grid, as well as an overall decrease in net plant output. Taken together with the positive growth in demand for electricity, this implies a need for accelerated capital build-outmore » in the power generation markets to accommodate both demand growth and decreased output at retrofitted plants. In this paper, the authors present the results of a study to assess the potential to use geothermal energy to provide boiler feedwater preheating, capturing efficiency improvements designed to offset the losses associated with CO 2 capture. Based on NETL benchmark cases and subsequent analysis of the application using site-specific data from the North Valmy power plant, several cases for CO 2 capture were evaluated. These included geothermally assisted MEA capture, CO2BOLs capture, and stand-alone hybrid power generation, compared with a baseline, no-geothermal case. Based on Case 10, and assuming 2.7 MMlb/h of geothermally sourced 150 ºC water, the parasitic power load associated with MEA capture could be offset by roughly seven percent, resulting in a small (~1 percent) overall loss to net power generation, but at levelized costs of electricity similar to the no-geothermal CCS case. For the CO 2BOLs case, the availability of 150°C geothermal fluid could allow the facility to not only offset the net power decrease associated with CO 2BOLs capture alone, but could increase nameplate capacity by two percent. The geothermally coupled CO 2BOLs case also decreases LCOE by 0.75 ¢/kWh relative to the non-hybrid CO 2BOLs case, with the improved performance over the MEA case driven by the lower regeneration temperature and associated duty for CO 2BOLs relative to MEA.« less

CO2 dispersion modelling over Paris region within the CO2-MEGAPARIS project

NASA Astrophysics Data System (ADS)

Lac, C.; Donnelly, R. P.; Masson, V.; Pal, S.; Donier, S.; Queguiner, S.; Tanguy, G.; Ammoura, L.; Xueref-Remy, I.

2012-10-01

Accurate simulation of the spatial and temporal variability of tracer mixing ratios over urban areas is challenging, but essential in order to utilize CO2 measurements in an atmospheric inverse framework to better estimate regional CO2 fluxes. This study investigates the ability of a high-resolution model to simulate meteorological and CO2 fields around Paris agglomeration, during the March field campaign of the CO2-MEGAPARIS project. The mesoscale atmospheric model Meso-NH, running at 2 km horizontal resolution, is coupled with the Town-Energy Balance (TEB) urban canopy scheme and with the Interactions between Soil, Biosphere and Atmosphere CO2-reactive (ISBA-A-gs) surface scheme, allowing a full interaction of CO2 between the surface and the atmosphere. Statistical scores show a good representation of the Urban Heat Island (UHI) and urban-rural contrasts. Boundary layer heights (BLH) at urban, sub-urban and rural sites are well captured, especially the onset time of the BLH increase and its growth rate in the morning, that are essential for tall tower CO2 observatories. Only nocturnal BLH at sub-urban sites are slightly underestimated a few nights, with a bias less than 50 m. At Eiffel tower, the observed spikes of CO2 maxima occur every morning exactly at the time at which the Atmospheric Boundary Layer (ABL) growth reaches the measurement height. The timing of the CO2 cycle is well captured by the model, with only small biases on CO2 concentrations, mainly linked to the misrepresentation of anthropogenic emissions, as the Eiffel site is at the heart of trafic emission sources. At sub-urban ground stations, CO2 measurements exhibit maxima at the beginning and at the end of each night, when the ABL is fully contracted, with a very strong spatio-temporal variability. The CO2 cycle at these sites is generally well reproduced by the model, even if some biases on the nocturnal maxima appear in the Paris plume parly due to small errors on the vertical transport, or in the vicinity of airports due to small errors on the horizontal transport (wind direction). A sensitivity test without urban parameterisation removes UHI and underpredicts nighttime BLH over urban and sub-urban sites, leading to large overestimation of nocturnal CO2 concentration at the sub-urban sites. The agreement of daytime and nighttime BLH and CO2 predictions of the reference simulation over Paris agglomeration demonstrates the potential of using the meso-scale system on urban and sub-urban area in the context of inverse modelling.

The role of CO2 capture and utilization in mitigating climate change

NASA Astrophysics Data System (ADS)

Mac Dowell, Niall; Fennell, Paul S.; Shah, Nilay; Maitland, Geoffrey C.

2017-04-01

To offset the cost associated with CO2 capture and storage (CCS), there is growing interest in finding commercially viable end-use opportunities for the captured CO2. In this Perspective, we discuss the potential contribution of carbon capture and utilization (CCU). Owing to the scale and rate of CO2 production compared to that of utilization allowing long-term sequestration, it is highly improbable the chemical conversion of CO2 will account for more than 1% of the mitigation challenge, and even a scaled-up enhanced oil recovery (EOR)-CCS industry will likely only account for 4-8%. Therefore, whilst CO2-EOR may be an important economic incentive for some early CCS projects, CCU may prove to be a costly distraction, financially and politically, from the real task of mitigation.

Modeling Effects of Bicarbonate Release on Carbonate Chemistry and pH of the North Sea: A Pilot Study for Atmospheric CO2 Reduction

NASA Astrophysics Data System (ADS)

Lettmann, K.; Kirchner, J.; Schnetger, B.; Wolff, J. O.; Brumsack, H. J.

2016-12-01

Rising CO2-emissions accompanying the industrial revolution are the main drivers for climate change and ocean acidification. Several methods have been developed to capture CO2 from effluents and reduce emission. Here, we consider a promising approach that mimics natural limestone weathering: CO2 in effluent gas streams reacts with calcium carbonate in a limestone suspension. The resulting bicarbonate-rich solution can be released into natural systems. In comparison to classical carbon capture and storage (CCS) methods this artificial limestone weathering is cheaper and does not involve using toxic chemical compounds. Additionally there is no need for the controversially discussed storage of CO2 underground. The reduction of CO2-emissions becomes more important for European industries as the EU introduced a system that limits the amount of allowable CO2-emissions. Therefore, large CO2 emitters are forced to find cheap methods for emission reduction, as they often cannot circumvent CO2-production. The method mentioned above is especially of interest for power plants located close to the coast that are already using seawater for cooling purposes. Thus, it is important to estimate the environmental effects if several coastal power plants will release high amounts of bicarbonate-rich waters into coastal waters, e.g. the North Sea. In a first pilot study, the unstructured-grid finite-volume community ocean model (FVCOM) was combined with a chemical submodul (mocsy 2.0) to model the hydrodynamic circulation and mixing of bicarbonate-rich effluents from a gas power plant located at the German North Sea coast. Here, we present the first preliminary results of this project, which include modelled changes of the North Sea carbonate system and changes in pH value after the introduction of these bicarbonate-rich waters on short time scales up to one year.

CO2 Capture Using Electric Fields: Low-Cost Electrochromic Film on Plastic for Net-Zero Energy Building

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2010-01-01

Broad Funding Opportunity Announcement Project: Two faculty members at Lehigh University created a new technique called supercapacitive swing adsorption (SSA) that uses electrical charges to encourage materials to capture and release CO2. Current CO2 capture methods include expensive processes that involve changes in temperature or pressure. Lehigh University’s approach uses electric fields to improve the ability of inexpensive carbon sorbents to trap CO2. Because this process uses electric fields and not electric current, the overall energy consumption is projected to be much lower than conventional methods. Lehigh University is now optimizing the materials to maximize CO2 capture and minimize themore » energy needed for the process.« less

Binding CO2 from Air by a Bulky Organometallic Cation Containing Primary Amines.

PubMed

Luo, Yang-Hui; Chen, Chen; Hong, Dan-Li; He, Xiao-Tong; Wang, Jing-Wen; Ding, Ting; Wang, Bo-Jun; Sun, Bai-Wang

2018-03-21

The organometallic cation 1 (Fe(bipy-NH 2 ) 3 2+ , bipy-NH 2 = 4,4'-diamino-2,2'-bipyridine), which was constructed in situ in solution, can bind CO 2 from air effectively with a stoichiometric ratio of 1:4 (1/CO 2 ), through the formation of "H-bonded CO 2 " species: [CO 2 -OH-CO 2 ] - and [CO 2 -CO 2 -OH] - . These two species, along with the captured individual CO 2 molecules, connected 1 into a novel 3D (three-dimensional) architecture, that was crystal 1·2(OH - )·4(CO 2 ). The adsorption isotherms, recycling investigations, and the heat capacity of 1 have been investigated; the results revealed that the organometallic cation 1 can be recycled at least 10 times for the real-world CO 2 capture applications. The strategies presented here may provide new hints for the development of new alkanolamine-related absorbents or technologies for CO 2 capture and sequestration.

Multiphase flow simulations of a moving fluidized bed regenerator in a carbon capture unit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarkar, Avik; Pan, Wenxiao; Suh, Dong-Myung

2014-10-01

To accelerate the commercialization and deployment of carbon capture technologies, computational fluid dynamics (CFD)-based tools may be used to model and analyze the performance of carbon capture devices. This work presents multiphase CFD-based flow simulations for the regeneration device responsible for extracting CO 2 from CO 2-loaded sorbent particles before the particles are recycled. The use of solid particle sorbents in this design is a departure from previously reported systems, where aqueous sorbents are employed. Another new feature is the inclusion of a series of perforated plates along the regenerator height. The influence of these plates on sorbent distribution ismore » examined for varying sorbent holdup, fluidizing gas velocity, and particle size. The residence time distribution of sorbents is also measured to classify the low regime as plug flow or well-mixed flow. The purpose of this work is to better understand the sorbent flow characteristics before reaction kinetics of CO 2 desorption can be implemented.« less

Intermediate Scale Laboratory Testing to Understand Mechanisms of Capillary and Dissolution Trapping during Injection and Post-Injection of CO 2 in Heterogeneous Geological Formations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Illangasekare, Tissa; Trevisan, Luca; Agartan, Elif

2015-03-31

Carbon Capture and Storage (CCS) represents a technology aimed to reduce atmospheric loading of CO 2 from power plants and heavy industries by injecting it into deep geological formations, such as saline aquifers. A number of trapping mechanisms contribute to effective and secure storage of the injected CO 2 in supercritical fluid phase (scCO 2) in the formation over the long term. The primary trapping mechanisms are structural, residual, dissolution and mineralization. Knowledge gaps exist on how the heterogeneity of the formation manifested at all scales from the pore to the site scales affects trapping and parameterization of contributing mechanismsmore » in models. An experimental and modeling study was conducted to fill these knowledge gaps. Experimental investigation of fundamental processes and mechanisms in field settings is not possible as it is not feasible to fully characterize the geologic heterogeneity at all relevant scales and gathering data on migration, trapping and dissolution of scCO 2. Laboratory experiments using scCO 2 under ambient conditions are also not feasible as it is technically challenging and cost prohibitive to develop large, two- or three-dimensional test systems with controlled high pressures to keep the scCO 2 as a liquid. Hence, an innovative approach that used surrogate fluids in place of scCO 2 and formation brine in multi-scale, synthetic aquifers test systems ranging in scales from centimeter to meter scale developed used. New modeling algorithms were developed to capture the processes controlled by the formation heterogeneity, and they were tested using the data from the laboratory test systems. The results and findings are expected to contribute toward better conceptual models, future improvements to DOE numerical codes, more accurate assessment of storage capacities, and optimized placement strategies. This report presents the experimental and modeling methods and research results.« less

CO2 mineral sequestration in oil-shale wastes from Estonian power production.

PubMed

Uibu, Mai; Uus, Mati; Kuusik, Rein

2009-02-01

In the Republic of Estonia, local low-grade carbonaceous fossil fuel--Estonian oil-shale--is used as a primary energy source. Combustion of oil-shale is characterized by a high specific carbon emission factor (CEF). In Estonia, the power sector is the largest CO(2) emitter and is also a source of huge amounts of waste ash. Oil-shale has been burned by pulverized firing (PF) since 1959 and in circulating fluidized-bed combustors (CFBCs) since 2004-2005. Depending on the combustion technology, the ash contains a total of up to 30% free Ca-Mg oxides. In consequence, some amount of emitted CO(2) is bound by alkaline transportation water and by the ash during hydraulic transportation and open-air deposition. The goal of this study was to investigate the possibility of improving the extent of CO(2) capture using additional chemical and technological means, in particular the treatment of aqueous ash suspensions with model flue gases containing 10-15% CO(2). The results indicated that both types of ash (PF and CFBC) could be used as sorbents for CO(2) mineral sequestration. The amount of CO(2) captured averaged 60-65% of the carbonaceous CO(2) and 10-11% of the total CO(2) emissions.

Active chemisorption sites in functionalized ionic liquids for carbon capture.

PubMed

Cui, Guokai; Wang, Jianji; Zhang, Suojiang

2016-07-25

Development of novel technologies for the efficient and reversible capture of CO2 is highly desired. In the last decade, CO2 capture using ionic liquids has attracted intensive attention from both academia and industry, and has been recognized as a very promising technology. Recently, a new approach has been developed for highly efficient capture of CO2 by site-containing ionic liquids through chemical interaction. This perspective review focuses on the recent advances in the chemical absorption of CO2 using site-containing ionic liquids, such as amino-based ionic liquids, azolate ionic liquids, phenolate ionic liquids, dual-functionalized ionic liquids, pyridine-containing ionic liquids and so on. Other site-containing liquid absorbents such as amine-based solutions, switchable solvents, and functionalized ionic liquid-amine blends are also investigated. Strategies have been discussed for how to activate the existent reactive sites and develop novel reactive sites by physical and chemical methods to enhance CO2 absorption capacity and reduce absorption enthalpy. The carbon capture mechanisms of these site-containing liquid absorbents are also presented. Particular attention has been paid to the latest progress in CO2 capture in multiple-site interactions by amino-free anion-functionalized ionic liquids. In the last section, future directions and prospects for carbon capture by site-containing ionic liquids are outlined.

Ab initio thermodynamic approach to identify mixed solid sorbents for CO 2 capture technology

DOE PAGES

Duan, Yuhua

2015-10-15

Because the current technologies for capturing CO 2 are still too energy intensive, new materials must be developed that can capture CO 2 reversibly with acceptable energy costs. At a given CO 2 pressure, the turnover temperature (T t) of the reaction of an individual solid that can capture CO 2 is fixed. Such T t may be outside the operating temperature range (ΔT o) for a practical capture technology. To adjust T t to fit the practical ΔT o, in this study, three scenarios of mixing schemes are explored by combining thermodynamic database mining with first principles density functionalmore » theory and phonon lattice dynamics calculations. Our calculated results demonstrate that by mixing different types of solids, it’s possible to shift T t to the range of practical operating temperature conditions. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO 2 capture reactions by the mixed solids of interest, we were able to identify the mixing ratios of two or more solids to form new sorbent materials for which lower capture energy costs are expected at the desired pressure and temperature conditions.« less

Hybrid Membrane/Absorption Process for Post-combustion CO2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Shiguang; Shou, S.; Pyrzynski, Travis

2013-12-31

This report summarizes scientific/technical progress made for bench-scale membrane contactor technology for post-combustion CO2 capture from DOE Contract No. DE-FE-0004787. Budget Period 1 (BP1) membrane absorber, Budget Period 2 (BP2) membrane desorber and Budget Period 3 (BP3) integrated system and field testing studies have been completed successfully and met or exceeded the technical targets (≥ 90% CO2 removal and CO2 purity of 97% in one membrane stage). Significant breakthroughs are summarized below: BP1 research: The feasibility of utilizing the poly (ether ether ketone), PEEK, based hollow fiber contractor (HFC) in combination with chemical solvents to separate and capture at leastmore » 90% of the CO2 from simulated flue gases has been successfully established. Excellent progress has been made as we have achieved the BP1 goal: ≥ 1,000 membrane intrinsic CO2 permeance, ≥ 90% CO2 removal in one stage, ≤ 2 psi gas side pressure drop, and ≥ 1 (sec)-1 mass transfer coefficient. Initial test results also show that the CO2 capture performance, using activated Methyl Diethanol Amine (aMDEA) solvent, was not affected by flue gas contaminants O2 (~3%), NO2 (66 ppmv), and SO2 (145 ppmv). BP2 research: The feasibility of utilizing the PEEK HFC for CO2-loaded solvent regeneration has been successfully established High CO2 stripping flux, one order of magnitude higher than CO2 absorption flux, have been achieved. Refined economic evaluation based on BP1 membrane absorber and BP2 membrane desorber laboratory test data indicate that the CO2 capture costs are 36% lower than DOE’s benchmark amine absorption technology. BP3 research: A bench-scale system utilizing a membrane absorber and desorber was integrated into a continuous CO2 capture process using contactors containing 10 to 20 ft2 of membrane area. The integrated process operation was stable through a 100-hour laboratory test, utilizing a simulated flue gas stream. Greater than 90% CO2 capture combined with 97% CO2 product purity was achieved throughout the test. Membrane contactor modules have been scaled from bench scale 2-inch diameter by 12-inch long (20 ft2 membrane surface area) modules to 4-inch diameter by 60-inch long pilot scale modules (165 ft2 membrane surface area). Pilot scale modules were tested in an integrated absorption/regeneration system for CO2 capture field tests at a coal-fired power plant (Midwest Generation’s Will County Station located in Romeoville, IL). Absorption and regeneration contactors were constructed utilizing high performance super-hydrophobic, nano-porous PEEK membranes with CO2 gas permeance of 2,000 GPU and a 1,000 GPU, respectively. Field tests using aMDEA solvent achieved greater than 90% CO2 removal in a single stage. The absorption mass transfer coefficient was 1.2 (sec)-1, exceeding the initial target of 1.0 (sec)-1. This mass transfer coefficient is over one order of magnitude greater than that of conventional gas/liquid contacting equipment. The economic evaluation based on field tests data indicates that the CO2 capture cost associated with membrane contactor technology is $54.69 (Yr 2011$)/tonne of CO2 captured when using aMDEA as a solvent. It is projected that the DOE’s 2025 cost goal of $40 (Yr 2011$)/tonne of CO2 captured can be met by decreasing membrane module cost and by utilizing advanced CO2 capture solvents. In the second stage of the field test, an advanced solvent, Hitachi’s H3-1 was utilized. The use of H3-1 solvent increased mass transfer coefficient by 17% as compared to aMDEA solvent. The high mass transfer coefficient of H3-1 solvent combined with much more favorable solvent regeneration requirements, indicate that the projected savings achievable with membrane contactor process can be further improved. H3-1 solvent will be used in the next pilot-scale development phase. The integrated absorption/regeneration process design and high performance membrane contactors developed in the current bench-scale program will be used as the base technology for future pilot-scale development.« less

Solar Reforming of Carbon Dioxide to Produce Diesel Fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dennis Schuetzle; Robert Schuetzle

2010-12-31

This project focused on the demonstration of an innovative technology, referred to as the Sunexus CO2 Solar Reformer, which utilizes waste CO2 as a feedstock for the efficient and economical production of synthetic diesel fuel using solar thermal energy as the primary energy input. The Sunexus technology employs a two stage process for the conversion of CO2 to diesel fuel. A solar reforming system, including a specially designed reactor and proprietary CO2 reforming catalyst, was developed and used to convert captured CO2 rich gas streams into syngas (primarily hydrogen and carbon monoxide) using concentrated solar energy at high conversion efficiencies.more » The second stage of the system (which has been demonstrated under other funding) involves the direct conversion of the syngas into synthetic diesel fuel using a proprietary catalyst (Terra) previously developed and validated by Pacific Renewable Fuels and Chemicals (PRFC). The overall system energy efficiency for conversion of CO2 to diesel fuel is 74%, due to the use of solar energy. The results herein describe modeling, design, construction, and testing of the Sunexus CO2 Solar Reformer. Extensive parametric testing of the solar reformer and candidate catalysts was conducted and chemical kinetic models were developed. Laboratory testing of the Solar Reformer was successfully completed using various gas mixtures, temperatures, and gas flow rates/space velocities to establish performance metrics which can be employed for the design of commercial plants. A variety of laboratory tests were conducted including dry reforming (CO2 and CH{sub 4}), combination dry/steam reforming (CO2, CH{sub 4} & H{sub 2}O), and tri-reforming (CO2, CH{sub 4}, H{sub 2}O & O{sub 2}). CH{sub 4} and CO2 conversions averaged 95-100% and 50-90% per reformer cycle, respectively, depending upon the temperatures and gas space velocities. No formation of carbon deposits (coking) on the catalyst was observed in any of these tests. A 16 ft. diameter, concentrating solar dish was modified to accommodate the Sunexus CO2 Solar Reformer and the integrated system was installed at the Pacific Renewable Fuels and Chemicals test site at McClellan, CA. Several test runs were conducted without catalyst during which the ceramic heat exchanger in the Sunexus Solar Reformer reached temperatures between 1,050 F (566 C) and 2,200 F (1,204 C) during the test period. A dry reforming mixture of CO2/CH{sub 4} (2.0/1.0 molar ratio) was chosen for all of the tests on the integrated solar dish/catalytic reformer during December 2010. Initial tests were carried out to determine heat transfer from the collimated solar beam to the catalytic reactor. The catalyst was operated successfully at a steady-state temperature of 1,125 F (607 C), which was sufficient to convert 35% of the 2/1 CO2/CH{sub 4} mixture to syngas. This conversion efficiency confirmed the results from laboratory testing of this catalyst which provided comparable syngas production efficiencies (40% at 1,200 F [650 C]) with a resulting syngas composition of 20% CO, 16% H{sub 2}, 39% CO2 and 25% CH{sub 4}. As based upon the laboratory results, it is predicted that 90% of the CO2 will be converted to syngas in the solar reformer at 1,440 F (782 C) resulting in a syngas composition of 50% CO: 43% H{sub 2}: 7% CO2: 0% CH{sub 4}. Laboratory tests show that the higher catalyst operating temperature of 1,440 F (782 C) for efficient conversion of CO2 can certainly be achieved by optimizing solar reactor heat transfer, which would result in the projected 90% CO2-to-syngas conversion efficiencies. Further testing will be carried out during 2011, through other funding support, to further optimize the solar dish CO2 reformer. Additional studies carried out in support of this project and described in this report include: (1) An Assessment of Potential Contaminants in Captured CO2 from Various Industrial Processes and Their Possible Effect on Sunexus CO2 Reforming Catalysts; (2) Recommended Measurement Methods for Assessing Contaminant Levels in Captured CO2 Streams; (3) An Assessment of Current Commercial Scale Fisher-Tropsch (F-T) Technologies for the Conversion of Syngas to Fuels; (4) An Overview of CO2 Capture Technologies from Various Industrial Sources; and (5) Lifecycle Analysis for the Capture and Conversion of CO2 to Synthetic Diesel Fuel. Commercial scale Sunexus CO2 Solar Reformer plant designs, proposed in this report, should be able to utilize waste CO2 from a wide variety of industrial sources to produce a directly usable synthetic diesel fuel that replaces petroleum derived fuel, thus improving the United States energy security while also sequestering CO2. Our material balance model shows that every 5.0 lbs of CO2 is transformed using solar energy into 6.26 lbs (1.0 U.S. gallon) of diesel fuel and into by-products, which includes water. Details are provided in the mass and energy model in this report.« less

Geological Sequestration of CO2 A Brief Overview and Potential for Application for Oklahoma

EPA Science Inventory

Geologic sequestration of CO2 is a component of C capture and storage (CCS), an emerging technology for reducing CO2 emissions to the atmosphere, and involves injection of captured CO2 into deep subsurface formations. Similar to the injection of hazardous wastes, before injection...

Carbon dioxide (CO2) sequestration in deep saline aquifers and formations: Chapter 3

USGS Publications Warehouse

Rosenbauer, Robert J.; Thomas, Burt

2010-01-01

Carbon dioxide (CO2) capture and sequestration in geologic media is one among many emerging strategies to reduce atmospheric emissions of anthropogenic CO2. This chapter looks at the potential of deep saline aquifers – based on their capacity and close proximity to large point sources of CO2 – as repositories for the geologic sequestration of CO2. The petrochemical characteristics which impact on the suitability of saline aquifers for CO2 sequestration and the role of coupled geochemical transport models and numerical tools in evaluating site feasibility are also examined. The full-scale commercial CO2 sequestration project at Sleipner is described together with ongoing pilot and demonstration projects.

Molecular modeling studies of interfacial reactions in wet supercritical CO2.

NASA Astrophysics Data System (ADS)

Glezakou, V.; McGrail, B. P.; Windisch, C. F.; Schaef, H. T.; Martin, P.

2011-12-01

In the recent years, Carbon Capture and Sequestration (CCS) technologies have gained considerable momentum in a globally organized effort to mitigate greenhouse emissions and adverse climate change. Co-sequestration refers to the capture and geologic sequestration of carbon dioxide and minor contaminants (sulfur compounds, NOx, Hg, etc.) in subsurface formations. Cosequestration offers the potential to make carbon management more economically acceptable to industry relative to sequestration of pure CO2. This may be achieved through significant savings in plant (and retrofit) capital cost, operating cost, and energy savings as well by eliminating the need for one or more individual pollutant capture systems (such as SO2 scrubbers). The latter point is important because co-sequestration may result in a net positive impact to the environment through avoided loss of power generation capacity from parasitic loads and reduced fuel needs. This paper will discuss our research on modeling, imaging and characterization of cosequestration processes and reactivity at a fundamental level. Our work examines the interactions of CO2-rich fluids with metal and mineral surfaces, and how these are affected by the presence of other gas components (e.g. SO2, H2O or NOx) commonly present in the CO2 streams. We have found that reactivity is also affected by the composition of the surface or, less obviously, by the surface exposed, for example, (104) vs (100 )of carbonate minerals. We combine experimental techniques such as XRD and Raman spectroscopy, which can detect and follow reactive processes, with ab initio modeling methods based on density functional theory, to establish a reliable correspondence between theory and experiment with predictive capability. Analysis of our molecular dynamics simulations, reveals structural information and vibrational density of states that can directly compare with XRD measurements and vibrational spectroscopy. While reactivity in CO2-containing aqueous environments has been widely studied, the reverse, i.e. reactivity in water-bearing condensed media, is not true. Our simulations show that mechanistic details in these environments can be drastically different, and they are very important in elucidating molecular transformations relevant to CCS or carbon conversion.

Simultaneous high efficiency capture of CO.sub.2 and H.sub.2S from pressurized gas

DOEpatents

Gal, Eli; Krishnan, Gopala N.; Jayaweera, Indira S.

2016-10-11

Low-cost and energy-efficient CO.sub.2 and H.sub.2S capture is provided obtaining greater than 99.9% capture efficiency from pressurized gas. The acid species are captured in an ammonia solution, which is then regenerated by stripping the absorbed species. The solution can capture as much as 330 grams of CO.sub.2 and H.sub.2S per 1000 gram of water and when regenerated it produces pure pressurized acid gas containing more than 99.7% CO.sub.2 and H2S. The absorption of the acid species is accomplished in two absorbers in-series, each having multiple stages. More than 95% of the acid species are captured in the first absorber and the balance is captured in the second absorber to below 10 ppm concentration in the outlet gas. The two absorbers operate at temperatures ranging from 20-70 degrees Celsius. The two absorbers and the main stripper of the alkaline solution operate at similar pressures ranging from 5-200 bara.

Thermodynamic Properties of CO{sub 2} Capture Reaction by Solid Sorbents: Theoretical Predictions and Experimental Validations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duan, Yuhua; Luebke, David; Pennline, Henry

2012-01-01

It is generally accepted that current technologies for capturing CO{sub 2} are still too energy intensive. Hence, there is a critical need for development of new materials that can capture CO{sub 2} reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO{sub 2} capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO{sub 2} sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculatedmore » thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO{sub 2} adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO{sub 2} capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. These CO{sub 2} sorbent candidates were further considered for experimental validations. In this presentation, we first introduce our screening methodology with validating by solid dataset of alkali and alkaline metal oxides, hydroxides and bicarbonates which thermodynamic properties are available. Then, by studying a series of lithium silicates, we found that by increasing the Li{sub 2}O/SiO{sub 2} ratio in the lithium silicates their corresponding turnover temperatures for CO{sub 2} capture reactions can be increased. Compared to anhydrous K{sub 2}CO{sub 3}, the dehydrated K{sub 2}CO{sub 3}1.5H{sub 2}O can only be applied for post-combustion CO{sub 2} capture technology at temperatures lower than its phase transition (to anhydrous phase) temperature, which depends on the CO{sub 2} pressure and the steam pressure with the best range being PH{sub 2}O≤1.0 bar. Above the phase-transition temperature, the sorbent will be regenerated into anhydrous K{sub 2}CO{sub 3}. Our theoretical investigations on Na-promoted MgO sorbents revealed that the sorption process takes place through formation of the Na{sub 2}Mg(CO{sub 3}){sub 2} double carbonate with better reaction kinetics over porous MgO, that of pure MgO sorbent. The experimental sorption tests also indicated that the Na-promoted MgO sorbent has high reactivity and capacity towards CO{sub 2} sorption and can be easily regenerated either through pressure or temperature swing processes.« less

Bench-Scale Development of a Hot Carbonate Absorption Process with Crystallization-Enabled High-Pressure Stripping for Post-Combustion CO{sub 2} Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Yongqi; DeVries, Nicholas; Ruhter, David

A novel Hot Carbonate Absorption Process with Crystallization-Enabled High-Pressure Stripping (Hot-CAP) has been developed by the University of Illinois at Urbana-Champaign and Carbon Capture Scientific, LLC in this three-year, bench-scale project. The Hot-CAP features a concentrated carbonate solution (e.g., K{sub 2}CO{sub 3}) for CO{sub 2} absorption and a bicarbonate slurry (e.g., KHCO{sub 3}) for high-pressure CO{sub 2} stripping to overcome the energy use and other disadvantages associated with the benchmark monoethanolamine (MEA) process. The project was aimed at performing laboratory- and bench-scale experiments to prove its technical feasibility and generate process engineering and scale-up data, and conducting a techno-economic analysismore » (TEA) to demonstrate its energy use and cost competitiveness over MEA. To meet project goals and objectives, a combination of experimental, modeling, process simulation, and economic analysis studies were applied. Carefully designed and intensive experiments were conducted to measure thermodynamic and reaction engineering data relevant to four major unit operations in the Hot-CAP (i.e., CO{sub 2} absorption, CO{sub 2} stripping, bicarbonate crystallization, and sulfate reclamation). The rate promoters that could accelerate the CO{sub 2} absorption rate into the potassium carbonate/bicarbonate (PCB) solution to a level greater than that into the 5 M MEA solution were identified, and the superior performance of CO{sub 2} absorption into PCB was demonstrated in a bench-scale packed-bed column. Kinetic data on bicarbonate crystallization were developed and applied for crystallizer design and sizing. Parametric testing of high-pressure CO{sub 2} stripping with concentrated bicarbonate-dominant slurries at high temperatures ({>=}140{degrees}C) in a bench-scale stripping column demonstrated lower heat use than with MEA. The feasibility of a modified process for combining SO{sub 2} removal with CO{sub 2} capture was preliminarily demonstrated. In addition to the experimental studies, the technical challenges pertinent to fouling of slurry-handling equipment and the design of the crystallizer and stripper were addressed through consultation with vendors and engineering analyses. A process flow diagram of the Hot-CAP was then developed and a TEA was performed to compare the energy use and cost performance of a nominal 550-MWe subcritical pulverized coal (PC)-fired power plant without CO{sub 2} capture (DOE/NETL Case 9) with the benchmark MEA-based post-combustion CO{sub 2} capture (PCC; DOE/NETL Case 10) and the Hot-CAP-based PCC. The results revealed that the net power produced in the PC + Hot-CAP is 609 MWe, greater than the PC + MEA (550 MWe). The 20-year levelized cost of electricity (LCOE) for the PC + Hot-CAP, including CO{sub 2} transportation and storage, is 120.3 mills/kWh, a 60% increase over the base PC plant without CO{sub 2} capture. The LCOE increase for the Hot-CAP is 29% lower than that for MEA. TEA results demonstrated that the Hot-CAP is energy-efficient and cost-effective compared with the benchmark MEA process.« less

Investing carbon offsets in woody forests - the best solution for California?

NASA Astrophysics Data System (ADS)

Dass, P.; Houlton, B. Z.; Warlind, D.

2016-12-01

Increasing atmospheric carbon dioxide (CO2) concentrations from fossil fuel combustion, land conversion and biomass burning are principal to climate change and its manifolds risks on human health, the environment and the global economy. Effective mitigation of climate change thereby involves cutting fossil-fuel emissions at the source or capturing CO2 in engineered or natural ecosystem stocks, or both. The lifetime of CO2 in the atmosphere exceeds 100 years; thus, in the case of CO2 sequestration by natural ecosystems, the residence time of soil and vegetation carbon(C) is a critical component of the efficacy of C offsets in the marketplace, particularly in local to global Cap and Trade frameworks. Here we use a land-surface model to analyze trade-offs in C investment into natural forest vs. grassland sinks and the role of fire in driving the most sustained pathways of CO2 sequestration under Cap and Trade policies. We focus on the California Climate Exchange and AB32 as the model system for examining risks of CO2 offset investments by considering model-based scenarios of (a.) natural woody forests (mixture of trees, shrubs and grasslands) or (b.) pure grasslands (no woody vegetation allowed) under conditions of drought and changes in fire frequency. While forests capture more carbon than grasslands, the latter stores a greater fraction of C in below ground stocks, making it less vulnerable to climate-driven disturbances. Preliminary results for simulations carried out for the last century for the state of California corroborate this hypothesis: while trees capture 100 GgCyr-1 more than grasses, CO2 emissions due to fire is less by 20 GgCyr-1 from grasslands when compared to forest environments. Since policies need to regard potential future scenarios, we present results that investigate how the alternate systems of trees and grasses respond to (i.) the environmental conditions of the no-mitigation scenario (RCP 8.5) through the year 2100, (ii.) periods of extended drought and (iii.) environmental conditions favoring higher incidences of fire.

CO2 capture from humid flue gases and humid atmosphere using a microporous coppersilicate.

PubMed

Datta, Shuvo Jit; Khumnoon, Chutharat; Lee, Zhen Hao; Moon, Won Kyung; Docao, Son; Nguyen, Thanh Huu; Hwang, In Chul; Moon, Dohyun; Oleynikov, Peter; Terasaki, Osamu; Yoon, Kyung Byung

2015-10-16

Capturing CO2 from humid flue gases and atmosphere with porous materials remains costly because prior dehydration of the gases is required. A large number of microporous materials with physical adsorption capacity have been developed as CO2-capturing materials. However, most of them suffer from CO2 sorption capacity reduction or structure decomposition that is caused by co-adsorbed H2O when exposed to humid flue gases and atmosphere. We report a highly stable microporous coppersilicate. It has H2O-specific and CO2-specific adsorption sites but does not have H2O/CO2-sharing sites. Therefore, it readily adsorbs both H2O and CO2 from the humid flue gases and atmosphere, but the adsorbing H2O does not interfere with the adsorption of CO2. It is also highly stable after adsorption of H2O and CO2 because it was synthesized hydrothermally. Copyright © 2015, American Association for the Advancement of Science.

SO 2-Resistant Immobilized Amine Sorbents for CO 2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tumuluri, Uma

2014-01-01

The solid amine sorbent for CO 2 capture process has advantages of simplicity and low operating cost compared to the MEA (monoethanolamine) process. Solid amine sorbents reported so far suffered from either low CO 2 capture capacity or low stability in the flue gas environment. This project is aimed at developing a SO 2-resistant solid amine sorbent for capturing CO 2 from coal–fired power plants with SCR/FGD which emits SO 2ranging from 15 to 30 ppm and NO ranging from 5 to 10 ppm. The amine sorbent we developed in a previous project degraded rapidly with 65% decrease in themore » initial capture capacity in presence of 1% SO 2. This amine sorbent was further modified by coating with polyethyleneglycol (PEG) to increase the SO 2-resistance. Polyethylene glycol (PEG) was found to decrease the SO 2-amine interaction, resulting in the decrease in the maximum SO desorption temperature (Tmax ) of amine sorbent. The PEG-coated amine sorbent exhibited higher stability with only 40% decrease in the initial capture capacity compared to un-coated amine sorbents. The cost of the solid amine sorbent developed in this project is estimated to be less than $7.00/lb; the sorbent exhibited CO 2 capture capacity more than 2.3 mmol/g. The results of this study provided the scientific basis for further development of SO 2-resistant sorbents.« less

Rapid and Accurate Machine Learning Recognition of High Performing Metal Organic Frameworks for CO2 Capture.

PubMed

Fernandez, Michael; Boyd, Peter G; Daff, Thomas D; Aghaji, Mohammad Zein; Woo, Tom K

2014-09-04

In this work, we have developed quantitative structure-property relationship (QSPR) models using advanced machine learning algorithms that can rapidly and accurately recognize high-performing metal organic framework (MOF) materials for CO2 capture. More specifically, QSPR classifiers have been developed that can, in a fraction of a section, identify candidate MOFs with enhanced CO2 adsorption capacity (>1 mmol/g at 0.15 bar and >4 mmol/g at 1 bar). The models were tested on a large set of 292 050 MOFs that were not part of the training set. The QSPR classifier could recover 945 of the top 1000 MOFs in the test set while flagging only 10% of the whole library for compute intensive screening. Thus, using the machine learning classifiers as part of a high-throughput screening protocol would result in an order of magnitude reduction in compute time and allow intractably large structure libraries and search spaces to be screened.

Metal-Organic Frameworks as Potential Platforms for Carbon Dioxide Capture and Chemical Transformation

NASA Astrophysics Data System (ADS)

Gao, Wenyang

The anthropogenic carbon dioxide (CO2) emission into the atmosphere, mainly through the combustion of fossil fuels, has resulted in a balance disturbance of the carbon cycle. Overwhelming scientific evidence proves that the escalating level of atmospheric CO2 is deemed as the main culprit for global warming and climate change. It is thus imperative to develop viable CO2 capture and sequestration (CCS) technologies to reduce CO2 emissions, which is also essential to avoid the potential devastating effects in future. The drawbacks of energy-cost, corrosion and inefficiency for amine-based wet-scrubbing systems which are currently used in industry, have prompted the exploration of alternative approaches for CCS. Extensive efforts have been dedicated to the development of functional porous materials, such as activated carbons, zeolites, porous organic polymers, and metal-organic frameworks (MOFs) to capture CO2. However, these adsorbents are limited by either poor selectivity for CO2 separation from gas mixtures or low CO2 adsorption capacity. Therefore, it is still highly demanding to design next-generation adsorbent materials fulfilling the requirements of high CO2 selectivity and enough CO2 capacity, as well as high water/moisture stability under practical conditions. Metal-organic frameworks (MOFs) have been positioned at the forefront of this area as a promising type of candidate amongst various porous materials. This is triggered by the modularity and functionality of pore size, pore walls and inner surface of MOFs by use of crystal engineering approaches. In this work, several effective strategies, such as incorporating 1,2,3-triazole groups as moderate Lewis base centers into MOFs and employing flexible azamacrocycle-based ligands to build MOFs, demonstrate to be promising ways to enhance CO 2 uptake capacity and CO2 separation ability of porous MOFs. It is revealed through in-depth studies on counter-intuitive experimental observations that the local electric field favours more than the richness of exposed nitrogen atoms for the interactions between MOFs and CO2 molecules, which provides a new perspective for future design of new MOFs and other types of porous materials for CO2 capture. Meanwhile, to address the water/moisture stability issue of MOFs, remote stabilization of copper paddlewheel clusters is achieved by strengthening the bonding between organic ligands and triangular inorganic copper trimers, which in turn enhances the stability of the whole MOF network and provides a better understanding of the mechanism promoting prospective suitable MOFs with enhanced water stability. In contrast with CO2 capture by sorbent materials, the chemical transformation of the captured CO2 into value-added products represents an alternative which is attractive and sustainable, and has been of escalating interest. The nanospace within MOFs not only provides the inner porosity for CO2 capture, but also engenders accessible room for substrate molecules for catalytic purpose. It is demonstrated that high catalytic efficiency for chemical fixation of CO2 into cyclic carbonates under ambient conditions is achieved on MOF-based nanoreactors featuring a high-density of well-oriented Lewis active sites. Furthermore, described for the first time is that CO 2 can be successfully inserted into aryl C-H bonds of a MOF to generate carboxylate groups. This proof-of-concept study contributes a different perspective to the current landscape of CO2 capture and transformation. In closing, the overarching goal of this work is not only to seek efficient MOF adsorbents for CO2 capture, but also to present a new yet attractive scenario of CO2 utilization on MOF platforms.

Integrated CO 2 Storage and Brine Extraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hunter, Kelsey; Bielicki, Jeffrey M.; Middleton, Richard

Carbon dioxide (CO 2) capture, utilization, and storage (CCUS) can reduce CO 2 emissions from fossil fuel power plants by injecting CO 2 into deep saline aquifers for storage. CCUS typically increases reservoir pressure which increases costs, because less CO 2 can be injected, and risks such as induced seismicity. Extracting brine with enhanced water recovery (EWR) from the CO 2 storage reservoir can manage and reduce pressure in the formation, decrease the risks linked to reservoir overpressure (e.g., induced seismicity), increase CO 2 storage capacity, and enable CO 2 plume management. We modeled scenarios of CO 2 injection withmore » EWR into the Rock Springs Uplift (RSU) formation in southwest Wyoming. The Finite Element Heat and Mass Transfer Code (FEHM) was used to model CO 2 injection with brine extraction and the corresponding increase in pressure within the RSU. We analyzed the model for pressure management, CO 2 storage, CO 2 saturation, and brine extraction due to the quantity and location of brine extraction wells. The model limited CO 2 injection to a constant pressure increase of two MPa at the injection well with and without extracting brine at hydrostatic pressure. Finally, we found that brine extraction can be used as a technical and cost-effective pressure management strategy to limit reservoir pressure buildup and increase CO 2 storage associated with a single injection well.« less

Integrated CO 2 Storage and Brine Extraction

DOE PAGES

Hunter, Kelsey; Bielicki, Jeffrey M.; Middleton, Richard; ...

2017-08-18

Carbon dioxide (CO 2) capture, utilization, and storage (CCUS) can reduce CO 2 emissions from fossil fuel power plants by injecting CO 2 into deep saline aquifers for storage. CCUS typically increases reservoir pressure which increases costs, because less CO 2 can be injected, and risks such as induced seismicity. Extracting brine with enhanced water recovery (EWR) from the CO 2 storage reservoir can manage and reduce pressure in the formation, decrease the risks linked to reservoir overpressure (e.g., induced seismicity), increase CO 2 storage capacity, and enable CO 2 plume management. We modeled scenarios of CO 2 injection withmore » EWR into the Rock Springs Uplift (RSU) formation in southwest Wyoming. The Finite Element Heat and Mass Transfer Code (FEHM) was used to model CO 2 injection with brine extraction and the corresponding increase in pressure within the RSU. We analyzed the model for pressure management, CO 2 storage, CO 2 saturation, and brine extraction due to the quantity and location of brine extraction wells. The model limited CO 2 injection to a constant pressure increase of two MPa at the injection well with and without extracting brine at hydrostatic pressure. Finally, we found that brine extraction can be used as a technical and cost-effective pressure management strategy to limit reservoir pressure buildup and increase CO 2 storage associated with a single injection well.« less

Novel Silica Nanostructured Platforms with Engineered Surface Functionality and Spherical Morphology for Low-Cost High-Efficiency Carbon Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lai, Cheng-Yu; Radu, Daniela R.; Pizzi, Nicholas

Carbon capture is an integral part of the CO 2 mitigation efforts, and encompasses, among other measures, the demonstration of effective and inexpensive CO 2 capture technologies. The project demonstrated a novel platform—the amine-functionalized stellate mesoporous silica nanosphere (MSN)—for effective CO 2 absorption. The reported CO 2 absorption data are superior to the performance of other reported silica matrices utilized for carbon capture, featuring an amount of over 4 milimoles CO 2/g sorbent at low temperatures (in the range of 30-45 ºC), selected for simulating the temperature of actual flue gas. The reported platform is highly resilient, showing recyclability andmore » 85 % mass conservation of sorbent upon nine tested cycles. Importantly, the stellate MSNs show high CO 2 selectivity at room temperature, indicating that the presence of nitrogen in flue gas will not impair the CO 2 absorption performance. The results could lead to a simple and inexpensive new technology for CO 2 mitigation which could be implemented as measure of CO 2 mitigation in current fossil-fuel burning plants in the form of solid sorbent.« less

Modeling of nonequilibrium CO Fourth-Positive and CN Violet emission in CO2-N2 gases

NASA Astrophysics Data System (ADS)

Johnston, C. O.; Brandis, A. M.

2014-12-01

This work develops a chemical kinetic rate model for simulating nonequilibrium radiation from CO2-N2 gases, representative of Mars or Venus entry shock layers. Using recent EAST shock tube measurements of nonequilibrium CO 4th Positive and CN Violet emission at pressures and velocities ranging from 0.10 to 1.0 Torr and 6 to 8 km/s, the rate model is developed through an optimization procedure that minimizes the disagreement between the measured and simulated nonequilibrium radiance profiles. Only the dissociation rates of CO2, CO, and NO, along with the CN + O and CO + N rates were treated as unknown in this optimization procedure, as the nonequilibrium radiance was found to be most sensitive to them. The other rates were set to recent values from the literature. Increases in over a factor of 5 in the CO dissociation rate relative to the previous widely used value were found to provide the best agreement with measurements, while the CO2 rate was not changed. The developed model is found to capture the measured nonequilibrium radiance of CO 4th Positive and CN Violet within error bars of ±30%.

Evaluation of Fe-containing Li2CuO2 on CO2 capture performed at different physicochemical conditions.

PubMed

Yañez-Aulestia, Ana; Ovalle-Encinia, Oscar; Pfeiffer, Heriberto

2018-06-05

Li 2 CuO 2 and different iron-containing Li 2 CuO 2 samples were synthesized by solid state reaction. On iron-containing samples, atomic sites of copper are substituted by iron ions in the lattice (XRD and Rietveld analyses). Iron addition induces copper release from Li 2 CuO 2 , which produce cationic vacancies and CuO, due to copper (Cu 2+ ) and iron (Fe 3+ ) valence differences. Two different physicochemical conditions were used for analyzing CO 2 capture on these samples; (i) high temperature and (ii) low temperature in presence of water vapor. At high temperatures, iron addition increased CO 2 chemisorption, due to structural and chemical variations on Li 2 CuO 2 . Kinetic analysis performed by first order reaction and Eyring models evidenced that iron addition on Li 2 CuO 2 induced a faster CO 2 chemisorption but a higher thermal dependence. Conversely, CO 2 chemisorption at low temperature in water vapor presence practically did not vary by iron addition, although hydration and hydroxylation processes were enhanced. Moreover, under these physicochemical conditions the whole sorption process became slower on iron-containing samples, due to metal oxides presence.

Extraction of Mg(OH)2 from Mg silicate minerals with NaOH assisted with H2O: implications for CO2 capture from exhaust flue gas.

PubMed

Madeddu, Silvia; Priestnall, Michael; Godoy, Erik; Kumar, R Vasant; Raymahasay, Sugat; Evans, Michael; Wang, Ruofan; Manenye, Seabelo; Kinoshita, Hajime

2015-01-01

The utilisation of Mg(OH)2 to capture exhaust CO2 has been hindered by the limited availability of brucite, the Mg(OH)2 mineral in natural deposits. Our previous study demonstrated that Mg(OH)2 can be obtained from dunite, an ultramafic rock composed of Mg silicate minerals, in highly concentrated NaOH aqueous systems. However, the large quantity of NaOH consumed was considered an obstacle for the implementation of the technology. In the present study, Mg(OH)2 was extracted from dunite reacted in solid systems with NaOH assisted with H2O. The consumption of NaOH was reduced by 97% with respect to the NaOH aqueous systems, maintaining a comparable yield of Mg(OH)2 extraction, i.e. 64.8-66%. The capture of CO2 from a CO2-N2 gas mixture was tested at ambient conditions using a Mg(OH)2 aqueous slurry. Mg(OH)2 almost fully dissolved and reacted with dissolved CO2 by forming Mg(HCO3)2 which remained in equilibrium storing the CO2 in the aqueous solution. The CO2 balance of the process was assessed from the emissions derived from the power consumption for NaOH production and Mg(OH)2 extraction together with the CO2 captured by Mg(OH)2 derived from dunite. The process resulted as carbon neutral when dunite is reacted at 250 °C for durations of 1 and 3 hours and CO2 is captured as Mg(HCO3)2.

CO2 dispersion modelling over Paris region within the CO2-MEGAPARIS project

NASA Astrophysics Data System (ADS)

Lac, C.; Donnelly, R. P.; Masson, V.; Pal, S.; Riette, S.; Donier, S.; Queguiner, S.; Tanguy, G.; Ammoura, L.; Xueref-Remy, I.

2013-05-01

Accurate simulation of the spatial and temporal variability of tracer mixing ratios over urban areas is a challenging and interesting task needed to be performed in order to utilise CO2 measurements in an atmospheric inverse framework and to better estimate regional CO2 fluxes. This study investigates the ability of a high-resolution model to simulate meteorological and CO2 fields around Paris agglomeration during the March field campaign of the CO2-MEGAPARIS project. The mesoscale atmospheric model Meso-NH, running at 2 km horizontal resolution, is coupled with the Town Energy Balance (TEB) urban canopy scheme and with the Interactions between Soil, Biosphere and Atmosphere CO2-reactive (ISBA-A-gs) surface scheme, allowing a full interaction of CO2 modelling between the surface and the atmosphere. Statistical scores show a good representation of the urban heat island (UHI) with stronger urban-rural contrasts on temperature at night than during the day by up to 7 °C. Boundary layer heights (BLH) have been evaluated on urban, suburban and rural sites during the campaign, and also on a suburban site over 1 yr. The diurnal cycles of the BLH are well captured, especially the onset time of the BLH increase and its growth rate in the morning, which are essential for tall tower CO2 observatories. The main discrepancy is a small negative bias over urban and suburban sites during nighttime (respectively 45 m and 5 m), leading to a few overestimations of nocturnal CO2 mixing ratios at suburban sites and a bias of +5 ppm. The diurnal CO2 cycle is generally well captured for all the sites. At the Eiffel tower, the observed spikes of CO2 maxima occur every morning exactly at the time at which the atmospheric boundary layer (ABL) growth reaches the measurement height. At suburban ground stations, CO2 measurements exhibit maxima at the beginning and at the end of each night, when the ABL is fully contracted, with a strong spatio-temporal variability. A sensitivity test without urban parameterisation removes the UHI and underpredicts nighttime BLH over urban and suburban sites, leading to large overestimation of nocturnal CO2 mixing ratio at the suburban sites (bias of +17 ppm). The agreement between observation and prediction for BLH and CO2 concentrations and urban-rural increments, both day and night, demonstrates the potential of using the urban mesoscale system in the context of inverse modelling

Sorbent, Sublimation, and Icing Modeling Methods: Experimental Validation and Application to an Integrated MTSA Subassembly Thermal Model

NASA Technical Reports Server (NTRS)

Bower, Chad; Padilla, Sebastian; Iacomini, Christie; Paul, Heather L.

2010-01-01

This paper details the validation of modeling methods for the three core components of a Metabolic heat regenerated Temperature Swing Adsorption (MTSA) subassembly, developed for use in a Portable Life Support System (PLSS). The first core component in the subassembly is a sorbent bed, used to capture and reject metabolically produced carbon dioxide (CO2). The sorbent bed performance can be augmented with a temperature swing driven by a liquid CO2 (LCO2) sublimation heat exchanger (SHX) for cooling the sorbent bed, and a condensing, icing heat exchanger (CIHX) for warming the sorbent bed. As part of the overall MTSA effort, scaled design validation test articles for each of these three components have been independently tested in laboratory conditions. Previously described modeling methodologies developed for implementation in Thermal Desktop and SINDA/FLUINT are reviewed and updated, their application in test article models outlined, and the results of those model correlations relayed. Assessment of the applicability of each modeling methodology to the challenge of simulating the response of the test articles and their extensibility to a full scale integrated subassembly model is given. The independent verified and validated modeling methods are applied to the development of a MTSA subassembly prototype model and predictions of the subassembly performance are given. These models and modeling methodologies capture simulation of several challenging and novel physical phenomena in the Thermal Desktop and SINDA/FLUINT software suite. Novel methodologies include CO2 adsorption front tracking and associated thermal response in the sorbent bed, heat transfer associated with sublimation of entrained solid CO2 in the SHX, and water mass transfer in the form of ice as low as 210 K in the CIHX.

Room-temperature ionic liquids and composite materials: platform technologies for CO(2) capture.

PubMed

Bara, Jason E; Camper, Dean E; Gin, Douglas L; Noble, Richard D

2010-01-19

Clean energy production has become one of the most prominent global issues of the early 21st century, prompting social, economic, and scientific debates regarding energy usage, energy sources, and sustainable energy strategies. The reduction of greenhouse gas emissions, specifically carbon dioxide (CO(2)), figures prominently in the discussions on the future of global energy policy. Billions of tons of annual CO(2) emissions are the direct result of fossil fuel combustion to generate electricity. Producing clean energy from abundant sources such as coal will require a massive infrastructure and highly efficient capture technologies to curb CO(2) emissions. Current technologies for CO(2) removal from other gases, such as those used in natural gas sweetening, are also capable of capturing CO(2) from power plant emissions. Aqueous amine processes are found in the vast majority of natural gas sweetening operations in the United States. However, conventional aqueous amine processes are highly energy intensive; their implementation for postcombustion CO(2) capture from power plant emissions would drastically cut plant output and efficiency. Membranes, another technology used in natural gas sweetening, have been proposed as an alternative mechanism for CO(2) capture from flue gas. Although membranes offer a potentially less energy-intensive approach, their development and industrial implementation lags far behind that of amine processes. Thus, to minimize the impact of postcombustion CO(2) capture on the economics of energy production, advances are needed in both of these areas. In this Account, we review our recent research devoted to absorptive processes and membranes. Specifically, we have explored the use of room-temperature ionic liquids (RTILs) in absorptive and membrane technologies for CO(2) capture. RTILs present a highly versatile and tunable platform for the development of new processes and materials aimed at the capture of CO(2) from power plant flue gas and in natural gas sweetening. The desirable properties of RTIL solvents, such as negligible vapor pressures, thermal stability, and a large liquid range, make them interesting candidates as new materials in well-known CO(2) capture processes. Here, we focus on the use of RTILs (1) as absorbents, including in combination with amines, and (2) in the design of polymer membranes. RTIL amine solvents have many potential advantages over aqueous amines, and the versatile chemistry of imidazolium-based RTILs also allows for the generation of new types of CO(2)-selective polymer membranes. RTIL and RTIL-based composites can compete with, or improve upon, current technologies. Moreover, owing to our experience in this area, we are developing new imidazolium-based polymer architectures and thermotropic and lyotropic liquid crystals as highly tailorable materials based on and capable of interacting with RTILs.

Optimisation of dispersion parameters of Gaussian plume model for CO₂ dispersion.

PubMed

Liu, Xiong; Godbole, Ajit; Lu, Cheng; Michal, Guillaume; Venton, Philip

2015-11-01

The carbon capture and storage (CCS) and enhanced oil recovery (EOR) projects entail the possibility of accidental release of carbon dioxide (CO2) into the atmosphere. To quantify the spread of CO2 following such release, the 'Gaussian' dispersion model is often used to estimate the resulting CO2 concentration levels in the surroundings. The Gaussian model enables quick estimates of the concentration levels. However, the traditionally recommended values of the 'dispersion parameters' in the Gaussian model may not be directly applicable to CO2 dispersion. This paper presents an optimisation technique to obtain the dispersion parameters in order to achieve a quick estimation of CO2 concentration levels in the atmosphere following CO2 blowouts. The optimised dispersion parameters enable the Gaussian model to produce quick estimates of CO2 concentration levels, precluding the necessity to set up and run much more complicated models. Computational fluid dynamics (CFD) models were employed to produce reference CO2 dispersion profiles in various atmospheric stability classes (ASC), different 'source strengths' and degrees of ground roughness. The performance of the CFD models was validated against the 'Kit Fox' field measurements, involving dispersion over a flat horizontal terrain, both with low and high roughness regions. An optimisation model employing a genetic algorithm (GA) to determine the best dispersion parameters in the Gaussian plume model was set up. Optimum values of the dispersion parameters for different ASCs that can be used in the Gaussian plume model for predicting CO2 dispersion were obtained.

Modeling forest C and N allocation responses to free-air CO2 enrichment

NASA Astrophysics Data System (ADS)

Luus, Kristina; De Kauwe, Martin; Walker, Anthony; Werner, Christian; Iversen, Colleen; McCarthy, Heather; Medlyn, Belinda; Norby, Richard; Oren, Ram; Zak, Donald; Zaehle, Sönke

2015-04-01

Vegetation allocation patterns and soil-vegetation partitioning of C and N are predicted to change in response to rising atmospheric concentrations of CO2. These allocation responses to rising CO2 have been examined at the ecosystem level through through free-air CO2 enrichment (FACE) experiments, and their global implications for the timing of progressive N limitation (PNL) and C sequestration have been predicted for ~100 years using a variety of ecosystem models. However, recent FACE model-data syntheses studies [1,2,3] have indicated that ecosystem models do not capture the 5-10 year site-level ecosystem allocation responses to elevated CO2. This may be due in part to the missing representation of the rhizosphere interactions between plants and soil biota in models. Ecosystem allocation of C and N is altered by interactions between soil and vegetation through the priming effect: as plant N availability diminishes, plants respond physiologically by altering their tissue allocation strategies so as to increase rates of root growth and rhizodeposition. In response, either soil organic material begins to accumulate, which hastens the onset of PNL, or soil microbes start to decompose C more rapidly, resulting in increased N availability for plant uptake, which delays PNL. In this study, a straightforward approach for representing rhizosphere interactions in ecosystem models was developed through which C and N allocation to roots and rhizodeposition responds dynamically to elevated CO2 conditions, modifying soil decomposition rates without pre-specification of the direction in which soil C and N accumulation should shift in response to elevated CO2. This approach was implemented in a variety of ecosystem models ranging from stand (G'DAY), to land surface (CLM 4.5, O-CN), to dynamic global vegetation (LPJ-GUESS) models. Comparisons against data from three forest FACE sites (Duke, Oak Ridge & Rhinelander) indicated that representing rhizosphere interactions allowed models to more reliably capture responses of ecosystem C and N allocation to free-air CO2 enrichment because they were able to simulate the priming effect. Insights were therefore gained into between-site differences observed in forest FACE experiments, and the underlying physiological and biogeochemical mechanisms determining ecosystem C and N allocation responses to elevated CO2. References 1. De Kauwe, M. G., et al. (2014), Where does the carbon go? A model-data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites, New Phytologist, 203, 883-899. 2. Walker, A. P., et al. (2014), Comprehensive ecosystem model-data synthesis using multiple data sets at two temperate forest free-air CO2 enrichment experiments: Model performance at ambient CO2 concentration, Journal of Geophysical Research: Biogeosciences, 119, 937-964. 3. Zaehle, S., et al. (2014), Evaluation of 11 terrestrial carbon-nitrogen cycle models against observations from two temperate Free-Air CO2 Enrichment studies, New Phytologist, 202 (3), 803-822.

Reducing Energy-Related CO2 Emissions Using Accelerated Limestone Weathering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rau, G H; Knauss, K G; Langer, W H

2004-04-27

Following earlier descriptions, the use and impacts of accelerated weathering of limestone AWL; reaction: CO{sub 2} + H{sub 2}O + CaCO{sub 3} {yields} Ca{sup 2+} + 2(HCO{sub 3}{sup -}) as a CO{sub 2} capture and sequestration method is further explored. Since ready access to the ocean is likely an essential requirement for AWL, it is shown that significant limestone resources are relatively close to a majority of CO{sub 2}-emitting power plants along the coastal US. Furthermore, waste fines, representing more than 20% of current US crushed limestone production (>10{sup 9} tonnes/yr), could be used in many instances as an inexpensivemore » or free source of AWL carbonate. With limestone transportation to coastal sites then as the dominant cost variable, CO{sub 2} sequestration (plus capture) costs of $3-$4/tonne are achievable in certain locations. While there is vastly more limestone and water on earth than that required for AWL to capture and sequester all fossil fuel CO{sub 2} production, the transportation cost of bringing limestone, seawater, and waste CO{sub 2} into contact likely limits the method's applicability to perhaps 10-20% of US point-source emissions. Using a bench-scale laboratory reactor, it is shown that CO{sub 2} sequestration rates of 10{sup -6} to 10{sup -5} moles/sec per m{sup 2} of limestone surface area are readily achievable using seawater. This translates into reaction densities as high as 2 x 10{sup -2} tonnes CO{sub 2} m{sup -3}day{sup -1}, highly dependent on limestone particle size, solution turbulence and flow, and CO{sub 2} concentration. Modeling of AWL end-solution disposal in the ocean shows significantly reduced effects on ocean pH and carbonate chemistry relative to those caused by direct CO{sub 2} disposal into the atmosphere or ocean. In fact the increase in ocean Ca{sup 2+} and bicarbonate offered by AWL should significantly enhance the growth of corals and other marine calcifiers whose health is currently being threatened by anthropogenic CO{sub 2} invasion and pH reduction in the ocean.« less

Numerical modeling of experimental observations on gas formation and multi-phase flow of carbon dioxide in subsurface formations

NASA Astrophysics Data System (ADS)

Pawar, R.; Dash, Z.; Sakaki, T.; Plampin, M. R.; Lassen, R. N.; Illangasekare, T. H.; Zyvoloski, G.

2011-12-01

One of the concerns related to geologic CO2 sequestration is potential leakage of CO2 and its subsequent migration to shallow groundwater resources leading to geochemical impacts. Developing approaches to monitor CO2 migration in shallow aquifer and mitigate leakage impacts will require improving our understanding of gas phase formation and multi-phase flow subsequent to CO2 leakage in shallow aquifers. We are utilizing an integrated approach combining laboratory experiments and numerical simulations to characterize the multi-phase flow of CO2 in shallow aquifers. The laboratory experiments involve a series of highly controlled experiments in which CO2 dissolved water is injected in homogeneous and heterogeneous soil columns and tanks. The experimental results are used to study the effects of soil properties, temperature, pressure gradients and heterogeneities on gas formation and migration. We utilize the Finite Element Heat and Mass (FEHM) simulator (Zyvoloski et al, 2010) to numerically model the experimental results. The numerical models capture the physics of CO2 exsolution, multi-phase fluid flow as well as sand heterogeneity. Experimental observations of pressure, temperature and gas saturations are used to develop and constrain conceptual models for CO2 gas-phase formation and multi-phase CO2 flow in porous media. This talk will provide details of development of conceptual models based on experimental observation, development of numerical models for laboratory experiments and modelling results.

Optimizing the Costs of Solid Sorbent-Based CO 2 Capture Process Through Heat Integration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sjostrom, Sharon

2016-03-18

The focus of this project was the ADAsorb™ CO 2 Capture Process, a temperature-swing adsorption process that incorporates a three-stage fluidized bed as the adsorber and a single-stage fluidized bed as the regenerator. ADAsorb™ system was designed, fabricated, and tested under DOE award DEFE0004343. Two amine-based sorbents were evaluated in conjunction with the ADAsorb™ process: “BN”, an ion-exchange resin; and “OJ”, a metal organic framework (MOF) sorbent. Two cross heat exchanger designs were evaluated for use between the adsorber and regenerator: moving bed and fluidized bed. The fluidized bed approach was rejected fairly early in the project because the additionalmore » electrical load to power blowers or fans to overcome the pressure drop required for fluidization was estimated to be nominally three times the electrical power that could be generated from the steam saved through the use of the cross heat exchanger. The Energy Research Center at Lehigh University built and utilized a process model of the ADAsorb™ capture process and integrated this model into an existing model of a supercritical PC power plant. The Lehigh models verified that, for the ADAsorb™ system, the largest contributor to parasitic power was lost electrical generation, which was primarily electric power which the host plant could not generate due to the extraction of low pressure (LP) steam for sorbent heating, followed by power for the CO 2 compressor and the blower or fan power required to fluidize the adsorber and regenerator. Sorbent characteristics such as the impacts of moisture uptake, optimized adsorption and regeneration temperature, and sensitivity to changes in pressure were also included in the modeling study. Results indicate that sorbents which adsorb more than 1-2% moisture by weight are unlikely to be cost competitive unless they have an extremely high CO 2 working capacity that well exceeds 15% by weight. Modeling also revealed that reductions in adsorber pressure drop could negatively affect the CO 2 adsorption characteristics for sorbents with certain isobar adsorption characteristics like sorbent BN. Thus, reductions in pressure drop do not provide the efficiency benefits expected. A techno-economic assessment conducted during the project revealed that without heat integration, the a metal organic framework (MOF) sorbent used in conjunction with the ADAsorb™ process provided the opportunity for improved performance over the benchmark MEA process. While the addition of a cross heat exchanger and heat integration was found to significantly improve net unit heat rate, the additional equipment costs required to realize these improvements almost always outweighed the improvement in performance. The exception to this was for a supported amine sorbent and the addition of a moving bed cross heat exchanger alone or in conjunction with waste heat from the compressor used for supplemental regenerator heating. Perhaps one of the most important points to be drawn from the work conducted during this project is the significant influence of sorbent characteristics alone on the projected COE and LCOE associated with the ADAsorb™ process, and the implications associated with future improvements to solid sorbent CO 2 capture. The results from this project suggest that solid sorbent CO 2 capture will continue to see performance gains and lower system costs as further sorbent improvements are realized.« less

Predicting the ultimate potential of natural gas SOFC power cycles with CO2 capture - Part B: Applications

NASA Astrophysics Data System (ADS)

Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.

2016-09-01

An important advantage of solid oxide fuel cells (SOFC) as future systems for large scale power generation is the possibility of being efficiently integrated with processes for CO2 capture. Focusing on natural gas power generation, Part A of this work assessed the performances of advanced pressurised and atmospheric plant configurations (SOFC + GT and SOFC + ST, with fuel cell integration within a gas turbine or a steam turbine cycle) without CO2 separation. This Part B paper investigates such kind of power cycles when applied to CO2 capture, proposing two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs with internal reforming and low temperature CO2 separation process. The power plants are simulated at the 100 MW scale with a set of realistic assumptions about FC performances, main components and auxiliaries, and show the capability of exceeding 70% LHV efficiency with high CO2 capture (above 80%) and a low specific primary energy consumption for the CO2 avoided (1.1-2.4 MJ kg-1). Detailed results are presented in terms of energy and material balances, and a sensitivity analysis of plant performance is developed vs. FC voltage and fuel utilisation to investigate possible long-term improvements. Options for further improvement of the CO2 capture efficiency are also addressed.

CO 2 Binding Organic Liquids Gas Capture with Polarity Swing Assisted Regeneration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heldebrant, David

This report outlines the comprehensive bench-scale testing of the CO 2-binding organic liquids (CO 2BOLs) solvent platform and its unique Polarity Swing Assisted Regeneration (PSAR). This study outlines all efforts on a candidate CO 2BOL solvent molecule, including solvent synthesis, material characterization, preliminary toxicology studies, and measurement of all physical, thermodynamic and kinetic data, including bench-scale testing. Equilibrium and kinetic models and analysis were made using Aspen Plus™. Preliminary process configurations, a technoeconomic assessment and solvent performance projections for separating CO 2 from a subcritical coal-fired power plant are compared to the U.S. Department of Energy's Case 10 monoethanolamine baseline.

CO₂ carbonation under aqueous conditions using petroleum coke combustion fly ash.

PubMed

González, A; Moreno, N; Navia, R

2014-12-01

Fly ash from petroleum coke combustion was evaluated for CO2 capture in aqueous medium. Moreover the carbonation efficiency based on different methodologies and the kinetic parameters of the process were determined. The results show that petroleum coke fly ash achieved a CO2 capture yield of 21% at the experimental conditions of 12 g L(-1), 363°K without stirring. The carbonation efficiency by petroleum coke fly ash based on reactive calcium species was within carbonation efficiencies reported by several authors. In addition, carbonation by petroleum coke fly ash follows a pseudo-second order kinetic model. Copyright © 2014 Elsevier Ltd. All rights reserved.

Climate sensitivity and meridional overturning circulation in the late Eocene using GFDL CM2.1

NASA Astrophysics Data System (ADS)

Hutchinson, David K.; de Boer, Agatha M.; Coxall, Helen K.; Caballero, Rodrigo; Nilsson, Johan; Baatsen, Michiel

2018-06-01

The Eocene-Oligocene transition (EOT), which took place approximately 34 Ma ago, is an interval of great interest in Earth's climate history, due to the inception of the Antarctic ice sheet and major global cooling. Climate simulations of the transition are needed to help interpret proxy data, test mechanistic hypotheses for the transition and determine the climate sensitivity at the time. However, model studies of the EOT thus far typically employ control states designed for a different time period, or ocean resolution on the order of 3°. Here we developed a new higher resolution palaeoclimate model configuration based on the GFDL CM2.1 climate model adapted to a late Eocene (38 Ma) palaeogeography reconstruction. The ocean and atmosphere horizontal resolutions are 1° × 1.5° and 3° × 3.75° respectively. This represents a significant step forward in resolving the ocean geography, gateways and circulation in a coupled climate model of this period. We run the model under three different levels of atmospheric CO2: 400, 800 and 1600 ppm. The model exhibits relatively high sensitivity to CO2 compared with other recent model studies, and thus can capture the expected Eocene high latitude warmth within observed estimates of atmospheric CO2. However, the model does not capture the low meridional temperature gradient seen in proxies. Equatorial sea surface temperatures are too high in the model (30-37 °C) compared with observations (max 32 °C), although observations are lacking in the warmest regions of the western Pacific. The model exhibits bipolar sinking in the North Pacific and Southern Ocean, which persists under all levels of CO2. North Atlantic surface salinities are too fresh to permit sinking (25-30 psu), due to surface transport from the very fresh Arctic ( ˜ 20 psu), where surface salinities approximately agree with Eocene proxy estimates. North Atlantic salinity increases by 1-2 psu when CO2 is halved, and similarly freshens when CO2 is doubled, due to changes in the hydrological cycle.

Water impacts of CO2 emission performance standards for fossil fuel-fired power plants.

PubMed

Talati, Shuchi; Zhai, Haibo; Morgan, M Granger

2014-10-21

We employ an integrated systems modeling tool to assess the water impacts of the new source performance standards recently proposed by the U.S. Environmental Protection Agency for limiting CO2 emissions from coal- and gas-fired power plants. The implementation of amine-based carbon capture and storage (CCS) for 40% CO2 capture to meet the current proposal will increase plant water use by roughly 30% in supercritical pulverized coal-fired power plants. The specific amount of added water use varies with power plant and CCS designs. More stringent emission standards than the current proposal would require CO2 emission reductions for natural gas combined-cycle (NGCC) plants via CCS, which would also increase plant water use. When examined over a range of possible future emission standards from 1100 to 300 lb CO2/MWh gross, new baseload NGCC plants consume roughly 60-70% less water than coal-fired plants. A series of adaptation approaches to secure low-carbon energy production and improve the electric power industry's water management in the face of future policy constraints are discussed both quantitatively and qualitatively.

Synthesis of Size-Tunable CO2-Philic Imprinted Polymeric Particles (MIPs) for Low-Pressure CO2 Capture Using Oil-in-Oil Suspension Polymerization.

PubMed

Nabavi, Seyed Ali; Vladisavljević, Goran T; Zhu, Yidi; Manović, Vasilije

2017-10-03

Highly selective molecularly imprinted poly[acrylamide-co-(ethylene glycol dimethacrylate)] polymer particles (MIPs) for CO 2 capture were synthesized by suspension polymerization via oil-in-oil emulsion. Creation of CO 2 -philic, amide-decorated cavities in the polymer matrix led to a high affinity to CO 2 . At 0.15 bar CO 2 partial pressure, the CO 2 /N 2 selectivity was 49 (corresponding to 91% purity of the gas stream after regeneration), and reached 97 at ultralow CO 2 partial pressures. The imprinted polymers showed considerably higher CO 2 uptakes compared to their nonimprinted counterparts, and the maximum equilibrium CO 2 capture capacity of 1.1 mmol g -1 was achieved at 273 K. The heat of adsorption was below 32 kJ mol -1 and the temperature of onset of intense thermal degradation was 351-376 °C. An increase in monomer-to-cross-linker molar ratio in the dispersed phase up to 1:2.5 led to a higher affinity toward CO 2 due to higher density of selective amide groups in the polymer network. MIPs are a promising option for industrial packed and fluidized bed CO 2 capture systems due to large particles with a diameter up to 1200 μm and irregular oblong shapes formed due to arrested coalescence during polymerization, occurring as a result of internal elasticity of the partially polymerized semisolid drops.

Bottleneck Effect of N,N-Dimethylformamide in InOF-1: Increasing CO2 Capture in Porous Coordination Polymers.

PubMed

Sánchez-González, Elí; González-Zamora, Eduardo; Martínez-Otero, Diego; Jancik, Vojtech; Ibarra, Ilich A

2017-05-15

The bottleneck effect of confined N,N-dimethylformamide (DMF) molecules was observed in InOF-1 for the first time: CO 2 capture was remarkably enhanced in samples of as-synthesized InOF-1, thermally activated in such a way that a small residual amount of DMF molecules remained confined within the pores (DMF@InOF-1). Dynamic CO 2 adsorption experiments on DMF@InOF-1 exhibited a CO 2 capture of 8.06 wt % [1.5-fold higher than that of a fully activated InOF-1 (5.24%)]. DMF@InOF-1 can reversibly adsorb/desorb 8.09% CO 2 with no loss of CO 2 capacity after 10 cycles, and the desorption is accomplished by only turning the CO 2 flow off. Static CO 2 adsorption experiments (at 196 K) demonstrated a 1.4-fold CO 2 capture increase (from 5.5 mmol·g -1 , fully activated InOF-1, to 7.5 mmol·g -1 , DMF@InOF-1). Therefore, these CO 2 capture properties are the result of the presence of residual-confined DMF molecules within the InOF-1 framework and their interactions via a very strong hydrogen bond with the In 2 (μ-OH) groups, which prevent DMF leaching. The stability of this hydrogen bond is given by a perfect fit of the DMF molecule in the "dent" around the OH group that allows a nearly ideal orientation of the DMF molecule towards the OH group.

Pre-Combustion Carbon Dioxide Capture by a New Dual Phase Ceramic-Carbonate Membrane Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Jerry Y. S.

2015-01-31

This report documents synthesis, characterization and carbon dioxide permeation and separation properties of a new group of ceramic-carbonate dual-phase membranes and results of a laboratory study on their application for water gas shift reaction with carbon dioxide separation. A series of ceramic-carbonate dual phase membranes with various oxygen ionic or mixed ionic and electronic conducting metal oxide materials in disk, tube, symmetric, and asymmetric geometric configurations was developed. These membranes, with the thickness of 10 μm to 1.5 mm, show CO 2 permeance in the range of 0.5-5×10 -7 mol·m -2·s -1·Pa -1 in 500-900°C and measured CO 2/N 2more » selectivity of up to 3000. CO 2 permeation mechanism and factors that affect CO 2 permeation through the dual-phase membranes have been identified. A reliable CO 2 permeation model was developed. A robust method was established for the optimization of the microstructures of ceramic-carbonate membranes. The ceramic-carbonate membranes exhibit high stability for high temperature CO 2 separations and water gas shift reaction. Water gas shift reaction in the dual-phase membrane reactors was studied by both modeling and experiments. It is found that high temperature syngas water gas shift reaction in tubular ceramic-carbonate dual phase membrane reactor is feasible even without catalyst. The membrane reactor exhibits good CO 2 permeation flux, high thermal and chemical stability and high thermal shock resistance. Reaction and separation conditions in the membrane reactor to produce hydrogen of 93% purity and CO 2 stream of >95% purity, with 90% CO 2 capture have been identified. Integration of the ceramic-carbonate dual-phase membrane reactor with IGCC process for carbon dioxide capture was analyzed. A methodology was developed to identify optimum operation conditions for a membrane tube of given dimensions that would treat coal syngas with targeted performance. The calculation results show that the dual-phase membrane reactor could improve IGCC process efficiency but the cost of the membrane reactor with membranes having current CO 2 permeance is high. Further research should be directed towards improving the performance of the membranes and developing cost-effective, scalable methods for fabrication of dual-phase membranes and membrane reactors.« less

Polymer-silica hybrids for separation of CO2 and catalysis of organic reactions

NASA Astrophysics Data System (ADS)

Silva Mojica, Ernesto

Porous materials comprising polymeric and inorganic segments have attracted interest from the scientific community due to their unique properties and functionalities. The physical and chemical characteristics of these materials can be effectively exploited for adsorption applications. This dissertation covers the experimental techniques for fabrication of poly(vinyl alcohol) (PVA) and silica (SiO2) porous supports, and their functionalization with polyamines for developing adsorbents with potential applications in separation of CO2 and catalysis of organic reactions. The supports were synthesized by processes involving (i) covalent cross-linking of PVA, (ii) hydrolysis and poly-condensation of silica precursors (i,e,. sol-gel synthesis), and formation of porous structures via (iii) direct templating and (iv) phase inversion techniques. Their physical structure was controlled by the proper combination of the preparation procedures, which resulted in micro-structured porous materials in the form of micro-particles, membranes, and pellets. Their adsorption characteristics were tailored by functionalization with polyethyleneimine (PEI), and their physicochemical properties were characterized by vibrational spectroscopy (FTIR, UV-vis), microscopy (SEM), calorimetry (TGA, DSC), and adsorption techniques (BET, step-switch adsorption). Spectroscopic investigations of the interfacial cross-linking reactions of PEI and PVA with glutaraldehyde (GA) revealed that PEI catalyzes the cross-linking reactions of PVA in absence of external acid catalysts. In-situ IR spectroscopy coupled with a focal plane array (FPA) image detector allowed the characterization of a gradient interface on a PEI/PVA composite membrane and the investigation of the cross-linking reactions as a function of time and position. The results served as a basis to postulate possible intermediates, and propose the reaction mechanisms. The formulation of amine-functionalized CO2 capture sorbents was based on the spectroscopic investigation of the interactions of CO 2 with amine molecules under simulated CO2 capture conditions. Industrial CO2 capture processes involve fluidization and require degradation-resistant sorbents in the form of pellets. Agglomeration of silica-based CO2 capture sorbents involved the formulation of a polymer binder solution and the design of a scalable pelletization process. The characterization of these pellets revealed the formation of a CO 2-permeable polymer-silica network, which is resistant to attrition, and exhibits similar CO2 capture and degradation performance as the non-pelletized sorbents. The performance of these sorbents and pellets was tested in lab-scale and bench-scale adsorption units, using in-house fabricated fixed-bed and fluidized-bed reactors. A compartmental modeling technique was used to simulate the CO2 adsorption process and to elucidate the kinetic and thermodynamic parameters that impact the commercial viability of emerging CO2 capture technologies. The fundamental concepts and experimental techniques developed for the preparation of CO2 capture sorbents served as a basis for fabricating amine-functionalized polymer-silica hybrids for applications in catalysis of organic reactions. (i) Basic catalysts for carbon-carbon addition reactions were prepared by immobilization of amine molecules on silica supports. The activity of these catalysts and the mechanisms of base-catalyzed organic condensation reactions were investigated by an in-situ FTIR micro-scale reactor. (ii) Particle-loaded PVA composite membranes were selected for immobilization of glucose oxidase (GOx). GOx was immobilized by adsorption at pH values between 3.5 and 7.1. The results showed that adsorption was primarily achieved via hydrophobic interactions, and that PVA membranes loaded with amine-functionalized particles could help retain the activity of immobilized GOx by providing a proper hydrophilic/hydrophobic balance to the immobilized enzymes micro-environment.

The catalytic effect of H2O on the hydrolysis of CO32- in hydrated clusters and its implication in the humidity driven CO2 air capture.

PubMed

Xiao, Hang; Shi, Xiaoyang; Zhang, Yayun; Liao, Xiangbiao; Hao, Feng; Lackner, Klaus S; Chen, Xi

2017-10-18

The hydration of ions in nanoscale hydrated clusters is ubiquitous and essential in many physical and chemical processes. Here we show that the hydrolysis reaction is strongly affected by relative humidity. The hydrolysis of CO 3 2- with n = 1-8 water molecules is investigated using an ab initio method. For n = 1-5 water molecules, all the reactants follow a stepwise pathway to the transition state. For n = 6-8 water molecules, all the reactants undergo a direct proton transfer to the transition state with overall lower activation free energy. The activation free energy of the reaction is dramatically reduced from 10.4 to 2.4 kcal mol -1 as the number of water molecules increases from 1 to 6. Meanwhile, the degree of hydrolysis of CO 3 2- is significantly increased compared to the bulk water solution scenario. Incomplete hydration shells facilitate the hydrolysis of CO 3 2- with few water molecules to be not only thermodynamically favorable but also kinetically favorable. We showed that the chemical kinetics is not likely to constrain the speed of CO 2 air capture driven by the humidity-swing. Instead, the pore-diffusion of ions is expected to be the time-limiting step in the humidity driven CO 2 air capture. The effect of humidity on the speed of CO 2 air capture was studied by conducting a CO 2 absorption experiment using IER with a high ratio of CO 3 2- to H 2 O molecules. Our result is able to provide valuable insights into designing efficient CO 2 air-capture sorbents.

Ultralow Parasitic Energy for Postcombustion CO 2 Capture Realized in a Nickel Isonicotinate Metal–Organic Framework with Excellent Moisture Stability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nandi, Shyamapada; Collins, Sean; Chakraborty, Debanjan

2017-01-25

Metal-organic frameworks (MOFs) have attracted significant attention as solid sorbents in gas separation processes for low-energy postcombustion CO 2 capture. The parasitic energy (PE) has been put forward as a holistic parameter that measures how energy efficient (and therefore cost-effective) the CO 2 capture process will be using the material. In this work, we present a nickel isonicotinate based ultramicroporous MOF, 1 [Ni-(4PyC)(2)center dot DMF], that has the lowest PE for postcombustion CO, capture reported to date. We calculate a PE of 655 kJ/kg CO 2, which is lower than that of the best performing material previously reported, Mg-MOF-74. Further,more » 1 exhibits exceptional hydrolytic stability with the CO 2 adsorption isotherm being unchanged following 7 days of steam-treatment (>85% RH) or 6 months of exposure to the atmosphere. The diffusion coefficient of CO 2 in 1 is also 2 orders of magnitude higher than in zeolites currently used in industrial scrubbers. Breakthrough experiments show that 1 only loses 7% of its maximum CO 2 capacity under humid conditions.« less

Bench Scale Process for Low Cost CO 2 Capture Using a Phase-Changing Absorbent: Final Scientific/Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westendorf, Tiffany; Buddle, Stanlee; Caraher, Joel

The objective of this project is to design and build a bench-scale process for a novel phase-changing aminosilicone-based CO 2-capture solvent. The project will establish scalability and technical and economic feasibility of using a phase-changing CO 2-capture absorbent for post-combustion capture of CO 2 from coal-fired power plants. The U.S. Department of Energy’s goal for Transformational Carbon Capture Technologies is the development of technologies available for demonstration by 2025 that can capture 90% of emitted CO 2 with at least 95% CO 2 purity for less than $40/tonne of CO 2 captured. In the first budget period of the project,more » the bench-scale phase-changing CO2 capture process was designed using data and operating experience generated under a previous project (ARPA-e project DE-AR0000084). Sizing and specification of all major unit operations was completed, including detailed process and instrumentation diagrams. The system was designed to operate over a wide range of operating conditions to allow for exploration of the effect of process variables on CO 2 capture performance. In the second budget period of the project, individual bench-scale unit operations were tested to determine the performance of each of each unit. Solids production was demonstrated in dry simulated flue gas across a wide range of absorber operating conditions, with single stage CO 2 conversion rates up to 75mol%. Desorber operation was demonstrated in batch mode, resulting in desorption performance consistent with the equilibrium isotherms for GAP-0/CO 2 reaction. Important risks associated with gas humidity impact on solids consistency and desorber temperature impact on thermal degradation were explored, and adjustments to the bench-scale process were made to address those effects. Corrosion experiments were conducted to support selection of suitable materials of construction for the major unit operations in the process. The bench scale unit operations were assembled into a continuous system to support steady state system testing. In the third budget period of the project, continuous system testing was conducted, including closed-loop operation of the absorber and desober systems. Slurries of GAP-0/GAP-0 carbamate/water mixtures produced in the absorber were pumped successfully to the desorber unit, and regenerated solvent was returned to the absorber. A techno-economic analysis, EH&S risk assessment, and solvent manufacturability study were completed.« less

Low-Energy Solvents For Carbon Dioxide Capture Enabled By A Combination Of Enzymes And Vacuum Regeneration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salmon, Sonja; House, Alan; Liu, Kun

An integrated bench-scale system combining the attributes of the bio-renewable enzyme carbonic anhydrase (CA) with low-enthalpy CO2 absorption solvents and vacuum regeneration was designed, built and operated for 500 hours using simulated flue gas. The objective was to develop a CO2 capture process with improved efficiency and sustainability when compared to NETL Case 10 monoethanolamine (MEA) scrubbing technology. The use of CA accelerates inter-conversion between dissolved CO2 and bicarbonate ion to enhance CO2 absorption, and the use of low enthalpy CO2 absorption solvents makes it possible to regenerate the solvent at lower temperatures relative to the reference MEA-based solvent. Themore » vacuum regeneration-based integrated bench-scale system operated successfully for an accumulated 500 hours using aqueous 23.5 wt% K2CO3-based solvent containing 2.5 g/L enzyme to deliver an average 84% CO2 capture when operated with a 20% enzyme replenishment rate per ~7 hour steady-state run period. The total inlet gas flow was 30 standard liters per minute with 15% CO2 and 85% N2. The absorber temperature was 40°C and the stripper operated under 35 kPa pressure with an approximate 77°C stripper bottom temperature. Tests with a 30°C absorber temperature delivered >90% capture. On- and off-line operational measurements provided a full process data set, with recirculating enzyme, that allowed for enzyme replenishment and absorption/desorption kinetic parameter calculations. Dissolved enzyme replenishment and conventional process controls were demonstrated as straightforward approaches to maintain system performance. Preliminary evaluation of a novel flow-through ultrasonically enhanced regeneration system was also conducted, yet resulted in CO2 release within the range of temperature-dependent release, and further work would be needed to validate the benefits of ultrasonic enhanced stripping. A full technology assessment was completed in which four techno-economic cases for enzyme-enhanced aqueous K2CO3 solvent with vacuum stripping were considered and a corresponding set of sensitivity studies were developed. The cases were evaluated using bench-scale and laboratory-based observations, AspenPlus® process simulation and modeling, AspenTech’s CCE® Parametric Software, current vendor quotations, and project partners’ know-how of unit operations. Overall, the DOE target of 90% CO2 capture could be met using the benign enzyme-enhanced aqueous K2CO3-based alternative to NETL Case 10. The model-predicted plant COE performance, scaled to 550 MWe net output, was 9% higher than NETL Case 10 for an enzyme-activated case with minimized technical risk and highest confidence in physical system performance utilizing commercially available equipment. A COE improvement of 2.8% versus NETL Case 10 was predicted when favorable features of improved enzyme longevity and additional power output from a very low pressure (VLP) turbine were combined, wherein corresponding high capital and operational costs limited the level of COE benefit. The environmental, health and safety (EH&S) profile of the system was found to be favorable and was compliant with the Federal EH&S legislation reviewed. Further work on a larger scale test unit is recommended to reduce the level of uncertainty inherent in extrapolating findings from a bench-scale unit to a full scale PCC plant, and to further investigate several identified opportunities for improvement. Production feasibility and suitability of carbonic anhydrases for scale-up testing was confirmed both through the current project and through parallel efforts.« less

Promoting Ethylene Selectivity from CO2 Electroreduction on CuO Supported onto CO2 Capture Materials.

PubMed

Yang, Hui-Juan; Yang, Hong; Hong, Yu-Hao; Zhang, Peng-Yang; Wang, Tao; Chen, Li-Na; Zhang, Feng-Yang; Wu, Qi-Hui; Tian, Na; Zhou, Zhi-You; Sun, Shi-Gang

2018-03-09

Cu is a unique catalyst for CO 2 electroreduction, since it can catalyze CO 2 reduction to a series of hydrocarbons, alcohols, and carboxylic acids. Nevertheless, such Cu catalysts suffer from poor selectivity. High pressure of CO 2 is considered to facilitate the activity and selectivity of CO 2 reduction. Herein, a new strategy is presented for CO 2 reduction with improved C 2 H 4 selectivity on a Cu catalyst by using CO 2 capture materials as the support at ambient pressure. N-doped carbon (N x C) was synthesized through high-temperature carbonization of melamine and l-lysine. We observed that the CO 2 uptake capacity of N x C depends on both the microporous area and the content of pyridinic N species, which can be controlled by the carbonization temperature (600-800 °C). The as-prepared CuO/N x C catalysts exhibit a considerably higher C 2 H 4 faradaic efficiency (36 %) than CuO supported on XC-72 carbon black (19 %), or unsupported CuO (20 %). Moreover, there is a good linear relationship between the C 2 H 4 faradaic efficiency and CO 2 uptake capacity of the supports for CuO. The local high CO 2 concentration near Cu catalysts, created by CO 2 capture materials, was proposed to increase the coverage of CO intermediate, which is favorable for the coupling of two CO units in the formation of C 2 H 4 . This study demonstrates that pairing Cu catalysts with CO 2 capture supports is a promising approach for designing highly effective CO 2 reduction electrocatalysts. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comparison of volatiles and mosquito capture efficacy for three carbohydrate sources in a yeast-fermentation CO2 generator

USDA-ARS?s Scientific Manuscript database

Mosquito surveillance in remote areas with limited access to canisters of CO2 or dry ice will benefit from an effective alternative CO2 source. In this study, we document the differences in mosquito and non-mosquito capture rates from CO2 baited (dry ice or yeast fermentation of carbohydrates) CDC t...

High-Surface-Area CO2 Sponge: High Performance CO2 Scrubbing Based on Hollow Fiber-Supported Designer Ionic Liquid Sponges

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

IMPACCT Project: The team from ORNL and Georgia Tech is developing a new technology that will act like a sponge, integrating a new, alcohol-based ionic liquid into hollow fibers (magnified image, right) to capture CO2 from the exhaust produced by coal-fired power plants. Ionic liquids, or salts that exist in liquid form, are promising materials for carbon capture and storage, but their tendency to thicken when combined with CO2 limits their efficiency and poses a challenge for their development as a cost-effective alternative to current-generation solutions. Adding alcohol to the mix limits this tendency to thicken in the presence ofmore » CO2 but can also make the liquid more likely to evaporate, which would add significantly to the cost of CO2 capture. To solve this problem, ORNL is developing new classes of ionic liquids with high capacity for absorbing CO2. ORNL’s sponge would reduce the cost associated with the energy that would need to be diverted from power plants to capture CO2 and release it for storage.« less

Tandem mass spectrometry measurement of the collision products of carbamate anions derived from CO2 capture sorbents: paving the way for accurate quantitation.

PubMed

Jackson, Phil; Fisher, Keith J; Attalla, Moetaz Ibrahim

2011-08-01

The reaction between CO(2) and aqueous amines to produce a charged carbamate product plays a crucial role in post-combustion capture chemistry when primary and secondary amines are used. In this paper, we report the low energy negative-ion CID results for several anionic carbamates derived from primary and secondary amines commonly used as post-combustion capture solvents. The study was performed using the modern equivalent of a triple quadrupole instrument equipped with a T-wave collision cell. Deuterium labeling of 2-aminoethanol (1,1,2,2,-d(4)-2-aminoethanol) and computations at the M06-2X/6-311++G(d,p) level were used to confirm the identity of the fragmentation products for 2-hydroxyethylcarbamate (derived from 2-aminoethanol), in particular the ions CN(-), NCO(-) and facile neutral losses of CO(2) and water; there is precedent for the latter in condensed phase isocyanate chemistry. The fragmentations of 2-hydroxyethylcarbamate were generalized for carbamate anions derived from other capture amines, including ethylenediamine, diethanolamine, and piperazine. We also report unequivocal evidence for the existence of carbamate anions derived from sterically hindered amines (Tris(2-hydroxymethyl)aminomethane and 2-methyl-2-aminopropanol). For the suite of carbamates investigated, diagnostic losses include the decarboxylation product (-CO(2), 44 mass units), loss of 46 mass units and the fragments NCO(-) (m/z 42) and CN(-) (m/z 26). We also report low energy CID results for the dicarbamate dianion ((-)O(2)CNHC(2)H(4)NHCO(2)(-)) commonly encountered in CO(2) capture solution utilizing ethylenediamine. Finally, we demonstrate a promising ion chromatography-MS based procedure for the separation and quantitation of aqueous anionic carbamates, which is based on the reported CID findings. The availability of accurate quantitation methods for ionic CO(2) capture products could lead to dynamic operational tuning of CO(2) capture-plants and, thus, cost-savings via real-time manipulation of solvent regeneration energies.

Evaluation of Solid Sorbents as a Retrofit Technology for CO 2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sjostrom, Sharon

2016-06-02

ADA completed a DOE-sponsored program titled Evaluation of Solid Sorbents as a Retrofit Technology for CO 2 Capture under program DE-FE0004343. During this program, sorbents were analyzed for use in a post-combustion CO 2 capture process. A supported amine sorbent was selected based upon superior performance to adsorb a greater amount of CO 2 than the activated carbon sorbents tested. When the most ideal sorbent at the time was selected, it was characterized and used to create a preliminary techno-economic analysis (TEA). A preliminary 550 MW coal-fired power plant using Illinois #6 bituminous coal was designed with a solid sorbentmore » CO 2 capture system using the selected supported amine sorbent to both facilitate the TEA and to create the necessary framework to scale down the design to a 1 MWe equivalent slipstream pilot facility. The preliminary techno-economic analysis showed promising results and potential for improved performance for CO 2 capture compared to conventional MEA systems. As a result, a 1 MWe equivalent solid sorbent system was designed, constructed, and then installed at a coal-fired power plant in Alabama. The pilot was designed to capture 90% of the CO 2 from the incoming flue gas at 1 MWe net electrical generating equivalent. Testing was not possible at the design conditions due to changes in sorbent handling characteristics at post-regenerator temperatures that were not properly incorporated into the pilot design. Thus, severe pluggage occurred at nominally 60% of the design sorbent circulation rate with heated sorbent, although no handling issues were noted when the system was operated prior to bringing the regenerator to operating temperature. Testing within the constraints of the pilot plant resulted in 90% capture of the incoming CO 2 at a flow rate equivalent of 0.2 to 0.25 MWe net electrical generating equivalent. The reduction in equivalent flow rate at 90% capture was primarily the result of sorbent circulation limitations at operating temperatures combined with pre-loading of the sorbent with CO 2 prior to entering the adsorber. Specifically, CO 2-rich gas was utilized to convey sorbent from the regenerator to the adsorber. This gas was nominally 45°C below the regenerator temperature during testing. ADA’s post-combustion capture system with modifications to overcome pilot constraints, in conjunction with incorporating a sorbent with CO 2 working capacity of 15 g CO 2/100 g sorbent and a contact time of 10 to 15 minutes or less with flue gas could provide significant cost and performance benefits when compared to an MEA system.« less

Numerical modeling and analytical modeling of cryogenic carbon capture in a de-sublimating heat exchanger

NASA Astrophysics Data System (ADS)

Yu, Zhitao; Miller, Franklin; Pfotenhauer, John M.

2017-12-01

Both a numerical and analytical model of the heat and mass transfer processes in a CO2, N2 mixture gas de-sublimating cross-flow finned duct heat exchanger system is developed to predict the heat transferred from a mixture gas to liquid nitrogen and the de-sublimating rate of CO2 in the mixture gas. The mixture gas outlet temperature, liquid nitrogen outlet temperature, CO2 mole fraction, temperature distribution and de-sublimating rate of CO2 through the whole heat exchanger was computed using both the numerical and analytic model. The numerical model is built using EES [1] (engineering equation solver). According to the simulation, a cross-flow finned duct heat exchanger can be designed and fabricated to validate the models. The performance of the heat exchanger is evaluated as functions of dimensionless variables, such as the ratio of the mass flow rate of liquid nitrogen to the mass flow rate of inlet flue gas.

Alkyl amine and vegetable oil mixture-a viable candidate for CO2 capture and utilization.

PubMed

Uma Maheswari, A; Palanivelu, K

2017-02-01

In this present work, the absorption of CO 2 in alkyl amines and vegetable oil mixture has been evaluated. The results showed that the absorption is higher in alkyl amines and vegetable oil mixture compared with the aqueous alkyl amines. In addition to that, by employing the greener and non-toxic vegetable oil media, the CO 2 gas has been captured as well as converted into value-added products, such as carbamates of ethylenediamine, diethylenetriamine, and triethylenetetramine. The carbamates have been isolated and characterized by Fourier transform infrared and 1 H and 13 C nuclear magnetic resonance spectroscopic techniques. The formation of these products in precipitate form has not been observed in the case of aqueous medium. Among the various alkyl amine and vegetable oil combinations, triethylenetetramine in coconut oil medium showed the maximum CO 2 capture capacity of 72%. The coconut oil used for the process has been recovered, recycled, and reused for 3 cycles. Thus, this novel scheme seems to be a better alternative to conquer the drawback of aqueous amine-based CO 2 capture as well as for the capture and utilization of the CO 2 gas to gain the value-added products.

A Life Cycle Assessment Case Study of Coal-Fired Electricity Generation with Humidity Swing Direct Air Capture of CO2 versus MEA-Based Postcombustion Capture.

PubMed

van der Giesen, Coen; Meinrenken, Christoph J; Kleijn, René; Sprecher, Benjamin; Lackner, Klaus S; Kramer, Gert Jan

2017-01-17

Most carbon capture and storage (CCS) envisions capturing CO 2 from flue gas. Direct air capture (DAC) of CO 2 has hitherto been deemed unviable because of the higher energy associated with capture at low atmospheric concentrations. We present a Life Cycle Assessment of coal-fired electricity generation that compares monoethanolamine (MEA)-based postcombustion capture (PCC) of CO 2 with distributed, humidity-swing-based direct air capture (HS-DAC). Given suitable temperature, humidity, wind, and water availability, HS-DAC can be largely passive. Comparing energy requirements of HS-DAC and MEA-PCC, we find that the parasitic load of HS-DAC is less than twice that of MEA-PCC (60-72 kJ/mol versus 33-46 kJ/mol, respectively). We also compare other environmental impacts as a function of net greenhouse gas (GHG) mitigation: To achieve the same 73% mitigation as MEA-PCC, HS-DAC would increase nine other environmental impacts by on average 38%, whereas MEA-PCC would increase them by 31%. Powering distributed HS-DAC with photovoltaics (instead of coal) while including recapture of all background GHG, reduces this increase to 18%, hypothetically enabling coal-based electricity with net-zero life-cycle GHG. We conclude that, in suitable geographies, HS-DAC can complement MEA-PCC to enable CO 2 capture independent of time and location of emissions and recapture background GHG from fossil-based electricity beyond flue stack emissions.

Influence of high-temperature steam on the reactivity of CaO sorbent for CO₂ capture.

PubMed

Donat, Felix; Florin, Nicholas H; Anthony, Edward J; Fennell, Paul S

2012-01-17

Calcium looping is a high-temperature CO(2) capture technology applicable to the postcombustion capture of CO(2) from power station flue gas, or integrated with fuel conversion in precombustion CO(2) capture schemes. The capture technology uses solid CaO sorbent derived from natural limestone and takes advantage of the reversible reaction between CaO and CO(2) to form CaCO(3); that is, to achieve the separation of CO(2) from flue or fuel gas, and produce a pure stream of CO(2) suitable for geological storage. An important characteristic of the sorbent, affecting the cost-efficiency of this technology, is the decay in reactivity of the sorbent over multiple CO(2) capture-and-release cycles. This work reports on the influence of high-temperature steam, which will be present in flue (about 5-10%) and fuel (∼20%) gases, on the reactivity of CaO sorbent derived from four natural limestones. A significant increase in the reactivity of these sorbents was found for 30 cycles in the presence of steam (from 1-20%). Steam influences the sorbent reactivity in two ways. Steam present during calcination promotes sintering that produces a sorbent morphology with most of the pore volume associated with larger pores of ∼50 nm in diameter, and which appears to be relatively more stable than the pore structure that evolves when no steam is present. The presence of steam during carbonation reduces the diffusion resistance during carbonation. We observed a synergistic effect, i.e., the highest reactivity was observed when steam was present for both calcination and carbonation.

The Biological Deep Sea Hydrothermal Vent as a Model to Study Carbon Dioxide Capturing Enzymes

PubMed Central

Minic, Zoran; Thongbam, Premila D.

2011-01-01

Deep sea hydrothermal vents are located along the mid-ocean ridge system, near volcanically active areas, where tectonic plates are moving away from each other. Sea water penetrates the fissures of the volcanic bed and is heated by magma. This heated sea water rises to the surface dissolving large amounts of minerals which provide a source of energy and nutrients to chemoautotrophic organisms. Although this environment is characterized by extreme conditions (high temperature, high pressure, chemical toxicity, acidic pH and absence of photosynthesis) a diversity of microorganisms and many animal species are specially adapted to this hostile environment. These organisms have developed a very efficient metabolism for the assimilation of inorganic CO2 from the external environment. In order to develop technology for the capture of carbon dioxide to reduce greenhouse gases in the atmosphere, enzymes involved in CO2 fixation and assimilation might be very useful. This review describes some current research concerning CO2 fixation and assimilation in the deep sea environment and possible biotechnological application of enzymes for carbon dioxide capture. PMID:21673885

In silico discovery of metal-organic frameworks for precombustion CO2 capture using a genetic algorithm

PubMed Central

Chung, Yongchul G.; Gómez-Gualdrón, Diego A.; Li, Peng; Leperi, Karson T.; Deria, Pravas; Zhang, Hongda; Vermeulen, Nicolaas A.; Stoddart, J. Fraser; You, Fengqi; Hupp, Joseph T.; Farha, Omar K.; Snurr, Randall Q.

2016-01-01

Discovery of new adsorbent materials with a high CO2 working capacity could help reduce CO2 emissions from newly commissioned power plants using precombustion carbon capture. High-throughput computational screening efforts can accelerate the discovery of new adsorbents but sometimes require significant computational resources to explore the large space of possible materials. We report the in silico discovery of high-performing adsorbents for precombustion CO2 capture by applying a genetic algorithm to efficiently search a large database of metal-organic frameworks (MOFs) for top candidates. High-performing MOFs identified from the in silico search were synthesized and activated and show a high CO2 working capacity and a high CO2/H2 selectivity. One of the synthesized MOFs shows a higher CO2 working capacity than any MOF reported in the literature under the operating conditions investigated here. PMID:27757420

Increased light-use efficiency in northern terrestrial ecosystems indicated by CO 2 and greening observations

DOE PAGES

Ricciuto, Daniel M.; Mao, Jiafu; Shi, Xiaoying

2016-11-04

Observations show an increasing amplitude in the seasonal cycle of CO 2 (ASC) north of 45°N of 56 ± 9.8% over the last 50 years and an increase in vegetation greenness of 7.5 - 15% in high northern latitudes since the 1980s. However, the causes of these changes remain uncertain. Historical simulations from terrestrial biosphere models in the Multiscale Synthesis and Terrestrial Model Intercomparison Project are compared to the ASC and greenness observations, using the TM3 atmospheric transport model to translate surface fluxes into CO 2 concentrations. We find that the modeled change in ASC is too small but themore » mean greening trend is generally captured. Modeled increases in greenness are primarily driven by warming, whereas ASC changes are primarily driven by increasing CO 2. We suggest that increases in ecosystem-scale light use efficiency (LUE) have contributed to the observed ASC increase but are underestimated by current models. We highlight potential mechanisms that could increase modeled LUE.« less

Carbon dioxide capture using Sodium bicarbonate/Sodium carbonate supported on nanoporous Iron(III) oxide

NASA Astrophysics Data System (ADS)

Dutcher, Bryce

Strong evidence exists suggesting that anthropogenic emissions of CO 2, primarily from the combustion of fossil fuels, have been contributing to global climate change, including warming of the atmosphere and acidification of the oceans. These, in turn, lead to other effects such as melting of ice and snow cover, rising sea levels, severe weather patterns, and extinction of life forms. With these detrimental shifts in ecosystems already being observed, it becomes imperative to mitigate anthropogenic CO2. CO2 capture is typically a costly operation, usually due to the energy required for regeneration of the capture medium. Na2CO3 is one potential capture medium with the potential to decrease this energy requirement. Extensively researched as a potential sorbent for CO2, Na2CO3 is well known for its theoretically low energy requirement, due largely to its relatively low heat of reaction compared to other capture technologies. Its primary pitfalls, however, are its extremely low reaction rate during sorption and slow regeneration of Na2CO 3. Before Na2CO3 can be used as a CO2 sorbent, then, it is critical to increase its reaction rate. In order to do so, this project studied nanoporous FeOOH as a potential supporting material for Na2CO3. Because regeneration of the sorbent is the most energy-intensive step when using Na2CO3 for CO 2 sorption, this project focused on the decomposition of NaHCO 3, which is equivalent to CO2 desorption. Using BET, FTIR, XRD, XPS, SEM, TEM, magnetic susceptibility tests, and Mossbauer spectroscopy, we show FeOOH to be thermally stable both with and without the presence of NaHCO3 at temperatures necessary for sorption and regeneration, up to about 200°C. More significantly, we observe that FeOOH not only increases the surface area of NaHCO3, but also has a catalytic effect on the decomposition of NaHCO3, reducing activation energy from 80 kJ/mol to 44 kJ/mol. This reduction in activation energy leads to a significant increase in the reaction rate by a factor of nearly 50, which could translate into a substantial decrease in the cost of using Na2 CO3 for CO2 capture.

Ca-Embedded C2N: an efficient adsorbent for CO2 capture.

PubMed

Liu, Yuzhen; Meng, Zhaoshun; Guo, Xiaojian; Xu, Genjian; Rao, Dewei; Wang, Yuhui; Deng, Kaiming; Lu, Ruifeng

2017-10-25

Carbon dioxide as a greenhouse gas causes severe impacts on the environment, whereas it is also a necessary chemical feedstock that can be converted into carbon-based fuels via electrochemical reduction. To efficiently and reversibly capture CO 2 , it is important to find novel materials for a good balance between adsorption and desorption. In this study, we performed first-principles calculations and grand canonical Monte Carlo (GCMC) simulations, to systematically study metal-embedded carbon nitride (C 2 N) nanosheets for CO 2 capture. Our first-principles results indicated that Ca atoms can be uniformly trapped in the cavity center of C 2 N structure, while the transition metals (Sc, Ti, V, Cr, Mn, Fe, Co) are favorably embedded in the sites off the center of the cavity. The determined maximum number of CO 2 molecules with strong physisorption showed that Ca-embedded C 2 N monolayer is the most promising CO 2 adsorbent among all considered metal-embedded materials. Moreover, GCMC simulations revealed that at room temperature the gravimetric density for CO 2 adsorbed on Ca-embedded C 2 N reached 50 wt% at 30 bar and 23 wt% at 1 bar, higher than other layered materials, thus providing a satisfactory system for the CO 2 capture and utilization.

Ultrafast and Stable CO2 Capture Using Alkali Metal Salt-Promoted MgO-CaCO3 Sorbents.

PubMed

Cui, Hongjie; Zhang, Qiming; Hu, Yuanwu; Peng, Chong; Fang, Xiangchen; Cheng, Zhenmin; Galvita, Vladimir V; Zhou, Zhiming

2018-06-20

As a potential candidate for precombustion CO 2 capture at intermediate temperatures (200-400 °C), MgO-based sorbents usually suffer from low kinetics and poor cyclic stability. Herein, a general and facile approach is proposed for the fabrication of high-performance MgO-based sorbents via incorporation of CaCO 3 into MgO followed by deposition of a mixed alkali metal salt (AMS). The AMS-promoted MgO-CaCO 3 sorbents are capable of adsorbing CO 2 at an ultrafast rate, high capacity, and good stability. The CO 2 uptake of sorbent can reach as high as above 0.5 g CO 2 g sorbent -1 after only 5 min of sorption at 350 °C, accounting for vast majority of the total uptake. In addition, the sorbents are very stable even under severe but more realistic conditions (desorption in CO 2 at 500 °C), where the CO 2 uptake of the best sorbent is stabilized at 0.58 g CO 2 g sorbent -1 in 20 consecutive cycles. The excellent CO 2 capture performance of the sorbent is mainly due to the promoting effect of molten AMS, the rapid formation of CaMg(CO 3 ) 2 , and the plate-like structure of sorbent. The exceptional ultrafast rate and the good stability of the AMS-promoted MgO-CaCO 3 sorbents promise high potential for practical applications, such as precombustion CO 2 capture from integrated gasification combined cycle plants and sorption-enhanced water gas shift process.

Field Testing of Cryogenic Carbon Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sayre, Aaron; Frankman, Dave; Baxter, Andrew

Sustainable Energy Solutions has been developing Cryogenic Carbon Capture™ (CCC) since 2008. In that time two processes have been developed, the External Cooling Loop and Compressed Flue Gas Cryogenic Carbon Capture processes (CCC ECL™ and CCC CFG™ respectively). The CCC ECL™ process has been scaled up to a 1TPD CO2 system. In this process the flue gas is cooled by an external refrigerant loop. SES has tested CCC ECL™ on real flue gas slip streams from subbituminous coal, bituminous coal, biomass, natural gas, shredded tires, and municipal waste fuels at field sites that include utility power stations, heating plants, cementmore » kilns, and pilot-scale research reactors. The CO2 concentrations from these tests ranged from 5 to 22% on a dry basis. CO2 capture ranged from 95-99+% during these tests. Several other condensable species were also captured including NO2, SO2 and PMxx at 95+%. NO was also captured at a modest rate. The CCC CFG™ process has been scaled up to a .25 ton per day system. This system has been tested on real flue gas streams including subbituminous coal, bituminous coal and natural gas at field sites that include utility power stations, heating plants, and pilot-scale research reactors. CO2 concentrations for these tests ranged from 5 to 15% on a dry basis. CO2 capture ranged from 95-99+% during these tests. Several other condensable species were also captured including NO2, SO2 and PMxx at 95+%. NO was also captured at 90+%. Hg capture was also verified and the resulting effluent from CCC CFG™ was below a 1ppt concentration. This paper will focus on discussion of the capabilities of CCC, the results of field testing and the future steps surrounding the development of this technology.« less

The Concept and Experimental Investigation of CO2 and Steam Co-electrolysis for Resource Utilization in Space Exploration

NASA Technical Reports Server (NTRS)

Stoots, Carl; Mulloth, Lila M.; Luna, Bernadette; Varghese, Mini M.

2009-01-01

CO2 acquisition and utilization technologies will have a vital role in determining sustained and affordable life support and in-situ fuel production architectures for human and robotic exploration of Moon and Mars. For long-term human exploration to be practical, reliable technologies have to be implemented to capture and chemically reduce the metabolic CO2 from the cabin air to restitute oxygen consumption. Technologies that facilitate the in-situ capture and conversion of atmospheric CO2 to fuel are essential for a viable human mission to Mars and their demonstration on the moon is critical as well. This paper describes the concept and experimental investigation of a CO2 capture and reduction system that comprises an adsorption compressor and a CO2 and steam co-electrolysis unit. The process products include oxygen for life support and Syngas (CO and H2) for synthetic fuel production. Electrochemical performance in terms of CO2 conversion, oxygen production, and power consumption of a system with a capacity to process 1kg CO2 per day (1-person equivalent) will be discussed.

Stuart Cohen | NREL

Science.gov Websites

;Optimizing post-combustion CO2 capture in response to volatile electricity prices." International , S.M., H.L. Chalmers, M.E. Webber, C.W. King, and J. Gibbins. "Comparing post-combustion CO2 ., G.T. Rochelle, and M.E. Webber. "Optimal operation of flexible post- combustion CO2 capture in

BioCO2 - a multidisciplinary, biological approach using solar energy to capture CO2 while producing H2 and high value products.

PubMed

Skjånes, Kari; Lindblad, Peter; Muller, Jiri

2007-10-01

Many areas of algae technology have developed over the last decades, and there is an established market for products derived from algae, dominated by health food and aquaculture. In addition, the interest for active biomolecules from algae is increasing rapidly. The need for CO(2) management, in particular capture and storage is currently an important technological, economical and global political issue and will continue to be so until alternative energy sources and energy carriers diminish the need for fossil fuels. This review summarizes in an integrated manner different technologies for use of algae, demonstrating the possibility of combining different areas of algae technology to capture CO(2) and using the obtained algal biomass for various industrial applications thus bringing added value to the capturing and storage processes. Furthermore, we emphasize the use of algae in a novel biological process which produces H(2) directly from solar energy in contrast to the conventional CO(2) neutral biological methods. This biological process is a part of the proposed integrated CO(2) management scheme.

A methodology of the assessment of environmental and human health risks from amine emissions from post combustion CO2 capture technology

NASA Astrophysics Data System (ADS)

Korre, Anna; Manzoor, Saba; Simperler, Alexandra

2015-04-01

Post combustion CO2 capture (PCCC) technology in power plants using amines as solvent for CO2 capture, is one of the reduction technologies employed to combat escalating levels of CO2 in the atmosphere. However, amine solvents used for capturing CO2 produce negative emissions such as, nitrosamines and nitramines, which are suspected to be potent carcinogens. It is therefore essential to assess the atmospheric fate of these amine emissions in the atmosphere by studying their atmospheric chemistry, dispersion and transport pathways away from the source and deposition in the environment, so as to be able to assess accurately the risk posed to human health and the natural environment. An important knowledge gap until recently has been the consideration of the atmospheric chemistry of these amine emissions simultaneously with dispersion and deposition studies so as to perform reliable human health and environmental risk assessments. The authors have developed a methodology to assess the distribution of such emissions away from a post-combustion facility by studying the atmospheric chemistry of monoethanolamine, the most commonly used solvent for CO2 capture, and those of the resulting degradation amines, methylamine and dimethylamine. This was coupled with dispersion modeling calculations (Manzoor, et al., 2014; Manzoor et al,2015). Rate coefficients describing the entire atmospheric chemistry schemes of the amines studied were evaluated employing quantum chemical theoretical and kinetic modeling calculations. These coefficients were used to solve the advection-dispersion-chemical equation using an atmospheric dispersion model, ADMS 5. This methodology is applicable to any size of a power plant and at any geographical location. In this paper, the humman health risk assessment is integrated in the modelling study. The methodology is demonstrated on a case study on the UK's largest capture pilot plant, Ferrybridge CCPilot 100+, to estimate the dispersion, chemical transformation and transport pathways of the amines and their degradation products away from the emitting facilities for the worst case scenario. The obtained results are used in calculating the cancer risks centred on oral cancer slope factor (CSF), risk-specific dose (RSD) and tolerant risk level of these chemical discharges. According to the CSF and RSD relationship (WQSA, 2011), at high CSF the RSD is small i.e. resulting in a high potent carcinogen risk. The health risk assessment is performed by following the US EPA method (USEPA, 1992) which considers atmospheric concentrations of these pollutants (mg m-3, evaluated by the dispersion model), daily intake through inhalation (mg kg-1 d-1), inhalation rate (m3 d-1), body weight (kg), average time (d), exposure time (d), exposure frequency (d), absorption factor and retention factor. Deterministic and probabilistic risk estimation of human health risks caused by exposure to these chemical pollutant discharges are conducted as well. From the findings of this study, it is suggested that the developed methodology is reliable in determining the risk these amine emissions from PCCC technology pose to human health. With this reliable and a universal approach it is possible to assess the fate of the amine emissions which remains a key area to address for the large scale CCS implementation.

Updated (BP3) Technical and Economic Feasibility Study - Electrochemical Membrane for Carbon Dioxide Capture and Power Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghezel-Ayagh, Hossein

This topical report summarizes the results of an updated Technical & Economic Feasibility Study (T&EFS) which was conducted in Budget Period 3 of the project to evaluate the performance and cost of the Electrochemical Membrane (ECM)-based CO 2 capture system. The ECM technology is derived from commercially available inorganic membranes; the same used in FuelCell Energy’s commercial fuel cell power plants and sold under the trade name Direct FuelCell® (DFC®). The ECM stacks are utilized in the Combined Electric Power (generation) And Carbon dioxide Separation (CEPACS) systems which can be deployed as add-ons to conventional power plants (Pulverized Coal, Combinedmore » Cycle, etc.) or industrial facilities to simultaneously produce power while capturing >90% of the CO 2 from the flue gas. In this study, an ECM-based CEPACS plant was designed to capture and compress >90% of the CO 2 (for sequestration or beneficial use) from the flue gas of a reference 550 MW (nominal, net AC) Pulverized Coal (PC) Rankine Cycle (Subcritical steam) power plant. ECM performance was updated based on bench scale ECM stack test results. The system process simulations were performed to generate the CEPACS plant performance estimates. The performance assessment included estimation of the parasitic power consumption for CO 2 capture and compression, and the efficiency impact on the PC plant. While the ECM-based CEPACS system for the 550 MW PC plant captures 90% of CO 2 from the flue gas, it generates additional (net AC) power after compensating for the auxiliary power requirements of CO 2 capture and compression. An equipment list, ECM stacks packaging design, and CEPACS plant layout were developed to facilitate the economic analysis. Vendor quotes were also solicited. The economic feasibility study included estimation of CEPACS plant capital cost, cost of electricity (COE) analyses and estimation of cost per ton of CO 2 captured. The incremental COE for the ECM-based CO 2 capture is expected to meet U.S. DOE’s target of 35%. This study has indicated that CEPACS systems offer significant benefits with respect to cost, performance, water consumption and emissions to environment. The realization of these benefits will provide a single solution to carbon dioxide capture in addition to meeting the increasing demand for electricity.« less

Updated (BP3) Technical and Economic Feasibility Study - Electrochemical Membrane for Carbon Dioxide Capture and Power Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghezel-Ayagh, Hossein

This topical report summarizes the results of an updated Technical & Economic Feasibility Study (T&EFS) which was conducted in Budget Period 3 of the project to evaluate the performance and cost of the Electrochemical Membrane (ECM)-based CO2 capture system. The ECM technology is derived from commercially available inorganic membranes; the same used in FuelCell Energy’s commercial fuel cell power plants and sold under the trade name Direct FuelCell® (DFC®). The ECM stacks are utilized in the Combined Electric Power (generation) And Carbon dioxide Separation (CEPACS) systems which can be deployed as add-ons to conventional power plants (Pulverized Coal, Combined Cycle,more » etc.) or industrial facilities to simultaneously produce power while capturing >90% of the CO2 from the flue gas. In this study, an ECM-based CEPACS plant was designed to capture and compress >90% of the CO2 (for sequestration or beneficial use) from the flue gas of a reference 550 MW (nominal, net AC) Pulverized Coal (PC) Rankine Cycle (Subcritical steam) power plant. ECM performance was updated based on bench scale ECM stack test results. The system process simulations were performed to generate the CEPACS plant performance estimates. The performance assessment included estimation of the parasitic power consumption for CO2 capture and compression, and the efficiency impact on the PC plant. While the ECM-based CEPACS system for the 550 MW PC plant captures 90% of CO2 from the flue gas, it generates additional (net AC) power after compensating for the auxiliary power requirements of CO2 capture and compression. An equipment list, ECM stacks packaging design, and CEPACS plant layout were developed to facilitate the economic analysis. Vendor quotes were also solicited. The economic feasibility study included estimation of CEPACS plant capital cost, cost of electricity (COE) analyses and estimation of cost per ton of CO2 captured. The incremental COE for the ECM-based CO2 capture is expected to meet U.S. DOE’s target of 35%. This study has indicated that CEPACS systems offer significant benefits with respect to cost, performance, water consumption and emissions to environment. The realization of these benefits will provide a single solution to carbon dioxide capture in addition to meeting the increasing demand for electricity.« less

A Pareto analysis approach to assess relevant marginal CO{sub 2} footprint for petroleum products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tehrani, Nejad M. Alireza, E-mail: alireza.tehraninejad@gmail.com

2015-07-15

Recently, linear programing (LP) models have been extended to track the marginal CO{sub 2} intensity of automotive fuels at the refinery gate. The obtained CO{sub 2} data are recommended for policy making because they capture the economic and environmental tensions as well as the processing effects related to oil products. However, they are proven to be extremely sensitive to small perturbations and therefore useless in practice. In this paper, we first investigate the theoretical reasons of this drawback. Then, we develop a multiple objective LP framework to assess relevant marginal CO{sub 2} footprints that preserve both defensibility and stability atmore » a satisfactory level of acceptance. A case study illustrates this new methodology. - Highlights: • Refining LP models have limitations to provide useful marginal CO{sub 2} footprints. • A multi objective optimization framework is developed to assess relevant CO{sub 2} data. • Within a European Refinig industry, diesel is more CO{sub 2} intensive than gasoline.« less

CO2-Binding Organic Liquids Gas Capture with Polarity-Swing-Assisted Regeneration Full Technology Feasibility Study B1 - Solvent-based Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heldebrant, David J

PNNL, Fluor Corporation and Queens University (Kingston, ON) successfully completed a three year comprehensive study of the CO2BOL water-lean solvent platform with Polarity Swing Assisted Regeneration (PSAR). This study encompassed solvent synthesis, characterization, environmental toxicology, physical, thermodynamic and kinetic property measurements, Aspen Plus™ modeling and bench-scale testing of a candidate CO2BOL solvent molecule. Key Program Findings The key program findings are summarized as follows: • PSAR favorably reduced stripper duties and reboiler temperatures with little/no impact to absorption column • >90% CO2 capture was achievable at reasonable liquid-gas ratios in the absorber • High rich solvent viscosities (up to 600more » cP) were successfully demonstrated in the bench-scale system. However, the projected impacts of high viscosity to capital cost and operational limits compromised the other levelized cost of electricity benefits. • Low thermal conductivity of organics significantly increased the required cross exchanger surface area, and potentially other heat exchange surfaces. • CO2BOL had low evaporative losses during bench-scale testing • There was no evidence of foaming during bench scale testing • Current CO2BOL formulation costs project to be $35/kg • Ecotoxicity (Water Daphnia) was comparable between CO2BOL and MEA (169.47 versus 103.63 mg/L) • Full dehydration of the flue gas was determined to not be economically feasible. However, modest refrigeration (13 MW for the 550 MW reference system) was determined to be potentially economically feasible, and still produce a water-lean condition for the CO2BOLs (5 wt% steady-state water loading). • CO2BOLs testing with 5 wt% water loading did not compromise anhydrous performance behavior, and showed actual enhancement of CO2 capture performance. • Mass transfer of CO2BOLs was not greatly impeded by viscosity • Facile separation of antisolvent from lean CO2BOL was demonstrated on the bench cart • No measurable solvent degradation was observed over 4 months of testing – even with 5 wt% water present« less

CO2-Binding-Organic-Liquids-Enhanced CO2 Capture using Polarity-Swing-Assisted Regeneration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Jian; Kutnyakov, Igor; Koech, Phillip K.

A new solvent-based CO2 capture process couples the unique attributes of non-aqueous, CO2-binding organic liquids (CO2BOLs) with the newly discovered polarity-swing-assisted regeneration (PSAR) process that is unique to switchable ionic liquids. Laboratory measurements with PSAR indicate the ability to achieve a regeneration effect at 75°C comparable to that at 120°C using thermal regeneration only. Initial measurements also indicate that the kinetic behavior of CO2 release is also improved with PSAR. Abstract cleared PNWD-SA-9743

Polyethylenimine-incorporated zeolite 13X with mesoporosity for post-combustion CO2 capture

NASA Astrophysics Data System (ADS)

Chen, Chao; Kim, Su-Sung; Cho, Won-Seung; Ahn, Wha-Seung

2015-03-01

X-type zeolite with mesoporosity (Meso-13X) was prepared by using dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride as a mesopore-generating agent, and then modified with polyethylenimine (PEI) through a physical impregnation method to form a hybrid material (Meso-13X-PEI). Meso-13X with and without PEI was characterized by X-ray powder diffraction (XRD), N2 adsorption-desorption isotherm at 77 K, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Meso-13X-PEI exhibited higher CO2 capture capacity than PEI-modified zeolite 13X owing to its larger pore volume that accommodates more amine species inside the pore structure, and the mesoporosity also can facilitate dispersion of PEI molecules inside the pore channels. Compared to zeolite 13X, Meso-13X-PEI showed much higher CO2 capture selectivity (against N2) as well as higher CO2 capture capacity at relatively high temperature (e.g. 100 °C) and dilute CO2 concentration relevant to post-combustion conditions.

Subsurface capture of carbon dioxide

DOEpatents

Blount, Gerald; Siddal, Alvin A.; Falta, Ronald W.

2014-07-22

A process and apparatus of separating CO.sub.2 gas from industrial off-gas source in which the CO.sub.2 containing off-gas is introduced deep within an injection well. The CO.sub.2 gases are dissolved in the, liquid within the injection well while non-CO.sub.2 gases, typically being insoluble in water or brine, are returned to the surface. Once the CO.sub.2 saturated liquid is present within the injection well, the injection well may be used for long-term geologic storage of CO.sub.2 or the CO.sub.2 saturated liquid can be returned to the surface for capturing a purified CO.sub.2 gas.

Kinetics of CO2 diffusion in human carbonic anhydrase: a study using molecular dynamics simulations and the Markov-state model.

PubMed

Chen, Gong; Kong, Xian; Lu, Diannan; Wu, Jianzhong; Liu, Zheng

2017-05-10

Molecular dynamics (MD) simulations, in combination with the Markov-state model (MSM), were applied to probe CO 2 diffusion from an aqueous solution into the active site of human carbonic anhydrase II (hCA-II), an enzyme useful for enhanced CO 2 capture and utilization. The diffusion process in the hydrophobic pocket of hCA-II was illustrated in terms of a two-dimensional free-energy landscape. We found that CO 2 diffusion in hCA-II is a rate-limiting step in the CO 2 diffusion-binding-reaction process. The equilibrium distribution of CO 2 shows its preferential accumulation within a hydrophobic domain in the protein core region. An analysis of the committors and reactive fluxes indicates that the main pathway for CO 2 diffusion into the active site of hCA-II is through a binding pocket where residue Gln 136 contributes to the maximal flux. The simulation results offer a new perspective on the CO 2 hydration kinetics and useful insights toward the development of novel biochemical processes for more efficient CO 2 sequestration and utilization.

Bench Scale Development and Testing of Aerogel Sorbents for CO 2 Capture Final Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Begag, Redouane

The primary objective of this project was scaling up and evaluating a novel Amine Functionalized Aerogel (AFA) sorbent in a bench scale fluidized bed reactor. The project team (Aspen Aerogels, University of Akron, ADA-ES, and Longtail Consulting) has carried out numerous tests and optimization studies to demonstrate the CO 2 capture performance of the AFA sorbent in all its forms: powder, pellet, and bead. The CO 2 capture target performance of the AFA sorbent (all forms) were set at > 12 wt.% and > 6 wt.% for total and working CO 2 capacity, respectively (@ 40 °C adsorption / 100more » – 120 °C desorption). The optimized AFA powders outperformed the performance targets by more than 30%, for the total CO 2 capacity (14 - 20 wt.%), and an average of 10 % more for working CO 2 capacity (6.6 – 7.0 wt.%, and could be as high as 9.6 wt. % when desorbed at 120 °C). The University of Akron developed binder formulations, pellet production methods, and post treatment technology for increased resistance to attrition and flue gas contaminants. In pellet form the AFA total CO 2 capacity was ~ 12 wt.% (over 85% capacity retention of that of the powder), and there was less than 13% degradation in CO 2 capture capacity after 20 cycles in the presence of 40 ppm SO 2. ADA-ES assessed the performance of the AFA powder, pellet, and bead by analyzing sorption isotherms, water uptake analysis, cycling stability, jet cup attrition and crush tests. At bench scale, the hydrodynamic and heat transfer properties of the AFA sorbent pellet in fluidized bed conditions were evaluated at Particulate Solid Research, Inc. (PSRI). After the process design requirements were completed, by Longtail Consulting LLC, a techno-economic analysis was achieved using guidance from The National Energy Technology Laboratory (NETL) report. This report provides the necessary framework to estimate costs for a temperature swing post combustion CO 2 capture process using a bituminous coal fired, super-critical steam cycle power plant producing 550 MWe net generation with 90% CO 2 capture using a methylethylamine (MEA) solvent. Using the NETL report as guidance, the designed CO 2 capture system was analyzed on a cost basis to determine relative cost estimates between the benchmark MEA system and the AFA sorbent system.« less

Optimizing and Quantifying CO 2 Storage Resource in Saline Formations and Hydrocarbon Reservoirs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bosshart, Nicholas W.; Ayash, Scott C.; Azzolina, Nicholas A.

In an effort to reduce carbon dioxide (CO 2) emissions from large stationary sources, carbon capture and storage (CCS) is being investigated as one approach. This work assesses CO 2 storage resource estimation methods for deep saline formations (DSFs) and hydrocarbon reservoirs undergoing CO 2 enhanced oil recovery (EOR). Project activities were conducted using geologic modeling and simulation to investigate CO 2 storage efficiency. CO 2 storage rates and efficiencies in DSFs classified by interpreted depositional environment were evaluated at the regional scale over a 100-year time frame. A focus was placed on developing results applicable to future widespread commercial-scalemore » CO 2 storage operations in which an array of injection wells may be used to optimize storage in saline formations. The results of this work suggest future investigations of prospective storage resource in closed or semiclosed formations need not have a detailed understanding of the depositional environment of the reservoir to generate meaningful estimates. However, the results of this work also illustrate the relative importance of depositional environment, formation depth, structural geometry, and boundary conditions on the rate of CO 2 storage in these types of systems. CO 2 EOR occupies an important place in the realm of geologic storage of CO 2, as it is likely to be the primary means of geologic CO 2 storage during the early stages of commercial implementation, given the lack of a national policy and the viability of the current business case. This work estimates CO 2 storage efficiency factors using a unique industry database of CO 2 EOR sites and 18 different reservoir simulation models capturing fluvial clastic and shallow shelf carbonate depositional environments for reservoir depths of 1219 and 2438 meters (4000 and 8000 feet) and 7.6-, 20-, and 64-meter (25-, 66,- and 209-foot) pay zones. The results of this work provide practical information that can be used to quantify CO 2 storage resource estimates in oil reservoirs during CO 2 EOR operations (as opposed to storage following depletion) and the uncertainty associated with those estimates.« less

Development of a cost-effective CO2 adsorbent from petroleum coke via KOH activation

NASA Astrophysics Data System (ADS)

Jang, Eunji; Choi, Seung Wan; Hong, Seok-Min; Shin, Sangcheol; Lee, Ki Bong

2018-01-01

The capture of CO2 via adsorption is considered an effective technology for decreasing global warming issues; hence, adsorbents for CO2 capture have been actively developed. Taking into account cost-effectiveness and environmental concerns, the development of CO2 adsorbents from waste materials is attracting considerable attention. In this study, petroleum coke (PC), which is the carbon residue remaining after heavy oil upgrading, was used to produce high-value-added porous carbon for CO2 capture. Porous carbon materials were prepared by KOH activation using different weight ratios of KOH/PC (1:1, 2:1, 3:1, and 4:1) and activation temperatures (600, 700, and 800 °C). The specific surface area and total pore volume of resulting porous carbon materials increased with KOH amount, reaching up to 2433 m2/g and 1.11 cm3/g, respectively. The sample prepared under moderate conditions with a KOH/PC weight ratio of 2:1 and activation temperature of 700 °C exhibited the highest CO2 adsorption uptake of 3.68 mmol/g at 25 °C and 1 bar. Interestingly, CO2 adsorption uptake was linearly correlated with the volume of micropores less than 0.8 nm, indicating that narrow micropore volume is crucial for CO2 adsorption. The prepared porous carbon materials also exhibited good selectivity for CO2 over N2, rapid adsorption, facile regeneration, and stable adsorption-desorption cyclic performance, demonstrating potential as a candidate for CO2 capture.

Fluid Substitution Modeling to Determine Sensitivity of 3D Vertical Seismic Profile Data to Injected CO­2­ at an active Carbon Capture, Utilization and Storage Project, Farnsworth field, TX.

NASA Astrophysics Data System (ADS)

Haar, K. K.; Balch, R. S.

2015-12-01

The Southwest Regional Partnership on Carbon Sequestration monitors a CO2 capture, utilization and storage project at Farnsworth field, TX. The reservoir interval is a Morrowan age fluvial sand deposited in an incised valley. The sands are between 10 to 25m thick and located about 2800m below the surface. Primary oil recovery began in 1958 and by the late 1960's secondary recovery through waterflooding was underway. In 2009, Chaparral Energy began tertiary recovery using 100% anthropogenic CO2 sourced from an ethanol and a fertilizer plant. This constitutes carbon sequestration and fulfills the DOE's initiative to determine the best approach to permanent carbon storage. One purpose of the study is to understand CO­2 migration from injection wells. CO2­ plume spatial distribution for this project is analyzed with the use of time-lapse 3D vertical seismic profiles centered on CO2 injection wells. They monitor raypaths traveling in a single direction compared to surface seismic surveys with raypaths traveling in both directions. 3D VSP surveys can image up to 1.5km away from the well of interest, exceeding regulatory requirements for maximum plume extent by a factor of two. To optimize the timing of repeat VSP acquisition, the sensitivity of the 3D VSP surveys to CO2 injection was analyzed to determine at what injection volumes a seismic response to the injected CO­2 will be observable. Static geologic models were generated for pre-CO2 and post-CO2 reservoir states through construction of fine scale seismic based geologic models, which were then history matched via flow simulations. These generated static states of the model, where CO2­ replaces oil and brine in pore spaces, allow for generation of impedance volumes which when convolved with a representative wavelet generate synthetic seismic volumes used in the sensitivity analysis. Funding for the project is provided by DOE's National Energy Technology Laboratory (NETL) under Award No. DE-FC26-05NT42591.

Global carbon management using air capture and geosequestration at remote locations

NASA Astrophysics Data System (ADS)

Lackner, K. S.; Goldberg, D.

2014-12-01

CO2 emissions need not only stop; according the IPCC, emissions need to turn negative. This requires means to remove CO2 from air and store it safely and permanently. We outline a combination of secure geosequestration and direct capture of CO2 from ambient air to create negative emissions at remote locations. Operation at remote sites avoids many difficulties associated with capture at the source, where space for added equipment is limited, good storage sites are in short supply, and proximity to private property engenders resistance. Large Igneous Provinces have been tested as secure CO2 reservoirs. CO2 and water react with reservoir rock to form stable carbonates, permanently sequestering the carbon. Outfitting reservoirs in large igneous provinces far from human habitation with ambient air capture systems creates large CO2 sequestration sites. Their remoteness offers advantages in environmental security and public acceptance and, thus, can smooth the path toward CO2 stabilization. Direct capture of CO2 from ambient air appears energetically and economically viable and could be scaled up quickly. Thermodynamic energy requirements are very small and a number of approaches have shown to be energy efficient in practice. Sorbent technologies include supported organoamines, alkaline brines, and quaternary ammonium based ion-exchange resins. To demonstrate that the stated goals of low cost and low energy consumption can be reached at scale, public research and demonstration projects are essential. We suggest co-locating air capture and geosequestration at sites where renewable energy resources can power both activities. Ready renewable energy would also allow for the co-production of synthetic fuels. Possible locations with large wind and basalt resources include Iceland and Greenland, the north-western United States, the Kerguelen plateau, Siberia and Morocco. Capture and sequestration in these reservoirs could recover all of the emissions of the 20th century and still contribute to a carbon neutral economy throughout the 21st century. Mobilizing industrial infrastructure to these areas poses a challenge. However, the urgency of the climate problem requires immediate action, with economic incentives and commitments to site evaluation and engineering development.

Earth 2075 (CO2) - can Ocean-Amplified Carbon Capture (oacc) Impart Atmospheric CO2-SINKING Ability to CCS Fossil Energy?

NASA Astrophysics Data System (ADS)

Fry, R.; Routh, M.; Chaudhuri, S.; Fry, S.; Ison, M.; Hughes, S.; Komor, C.; Klabunde, K.; Sethi, V.; Collins, D.; Polkinghorn, W.; Wroobel, B.; Hughes, J.; Gower, G.; Shkolnik, J.

2017-12-01

Previous attempts to capture atmospheric CO2 by algal blooming were stalled by ocean viruses, zooplankton feeding, and/or bacterial decomposition of surface blooms, re-releasing captured CO2 instead of exporting it to seafloor. CCS fossil energy coupling could bypass algal bloom limits—enabling capture of 10 GtC/yr atmospheric CO2 by selective emiliania huxleyi (EHUX) blooming in mid-latitude open oceans, far from coastal waters and polar seas. This could enable a 500 GtC drawdown, 350 ppm restoration by 2050, 280 ppm CO2 by 2075, and ocean pH 8.2. White EHUX blooms could also reflect sunlight back into outer space and seed extra ocean cloud cover, via DMS release, to raise albedo 1.8%—restoring preindustrial temperature (ΔT = 0°C) by 2030. Open oceans would avoid post-bloom anoxia, exclusively a coastal water phenomenon. The EHUX calcification reaction initially sources CO2, but net sinking prevails in follow-up equilibration reactions. Heavier-than-water EHUX sink captured CO2 to the sea floor before surface decomposition occurs. Seeding EHUX high on their nonlinear growth curve could accelerate short-cycle secondary open-ocean blooming—overwhelming mid-latitude viruses, zooplankton, and competition from other algae. Mid-latitude "ocean deserts" exhibit low viral, zooplankton, and bacterial counts. Thermocline prevents nutrient upwelling that would otherwise promote competing algae. Adding nitrogen nutrient would foster exclusive EHUX blooming. Elevated EHUX seed levels could arise from sealed, pH-buffered, floating, seed-production bioreactors infused with 10% CO2 from carbon feedstock supplied by inland CCS fossil power plants capturing 90% of emissions as liquid CO2. Deep-water SPAR platforms extract natural gas from beneath the sea floor. On-platform Haber and pH processing could convert extracted CH4 to buffered NH4+ nutrient, enabling ≥0.7 GtC/yr of bioreactor seed production and 10 GtC/yr of amplified secondary open-ocean CO2 capture—making CCS fossil energy 1400% carbon negative.

Coordination effect-regulated CO2 capture with an alkali metal onium salts/crown ether system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Zhen-Zhen; Jiang, Deen; Zhu, Xiang

2014-01-01

A coordination effect was employed to realize equimolar CO2 absorption, adopting easily synthesized amino group containing absorbents (alkali metal onium salts). The essence of our strategy was to increase the steric hindrance of cations so as to enhance a carbamic acid pathway for CO2 capture. Our easily synthesized alkali metal amino acid salts or phenolates were coordinated with crown ethers, in which highly sterically hindered cations were obtained through a strong coordination effect of crown ethers with alkali metal cations. For example, a CO2 capacity of 0.99 was attained by potassium prolinate/18-crown-6, being characterized by NMR, FT-IR, and quantum chemistrymore » calculations to go through a carbamic acid formation pathway. The captured CO2 can be stripped under very mild conditions (50 degrees C, N-2). Thus, this protocol offers an alternative for the development of technological innovation towards efficient and low energy processes for carbon capture and sequestration.« less

Hierarchically Porous Carbon Materials for CO 2 Capture: The Role of Pore Structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Estevez, Luis; Barpaga, Dushyant; Zheng, Jian

2018-01-17

With advances in porous carbon synthesis techniques, hierarchically porous carbon (HPC) materials are being utilized as relatively new porous carbon sorbents for CO2 capture applications. These HPC materials were used as a platform to prepare samples with differing textural properties and morphologies to elucidate structure-property relationships. It was found that high microporous content, rather than overall surface area was of primary importance for predicting good CO2 capture performance. Two HPC materials were analyzed, each with near identical high surface area (~2700 m2/g) and colossally high pore volume (~10 cm3/g), but with different microporous content and pore size distributions, which ledmore » to dramatically different CO2 capture performance. Overall, large pore volumes obtained from distinct mesopores were found to significantly impact adsorption performance. From these results, an optimized HPC material was synthesized that achieved a high CO2 capacity of ~3.7 mmol/g at 25°C and 1 bar.« less

Sorbents with high efficiency for CO2 capture based on amines-supported carbon for biogas upgrading.

PubMed

Pino, Lidia; Italiano, Cristina; Vita, Antonio; Fabiano, Concetto; Recupero, Vincenzo

2016-10-01

Sorbents for CO 2 capture have been prepared by wet impregnation of a commercial active carbon (Ketjen-black, Akzo Nobel) with two CO 2 -philic compounds, polyethylenimine (PEI) and tetraethylenepentamine (TEPA), respectively. The effects of amine amount (from 10 to 70wt.%), CO 2 concentration in the feed, sorption temperature and gas hourly space velocity on the CO 2 capture performance have been investigated. The sorption capacity has been evaluated using the breakthrough method, with a fixed bed reactor equipped with on line gas chromatograph. The samples have been characterized by N 2 adsorption-desorption, scanning electron microscopy and energy dispersive X-ray (SEM/EDX). A promising CO 2 sorption capacity of 6.90 mmol/g sorbent has been obtained with 70wt.% of supported TEPA at 70°C under a stream containing 80vol% of CO 2 . Sorption tests, carried out with simulated biogas compositions (CH 4 /CO 2 mixtures), have revealed an appreciable CO 2 separation selectivity; stable performance was maintained for 20 adsorption-desorption cycles. Copyright © 2016. Published by Elsevier B.V.

Design of Aminopolymer Structure to Enhance Performance and Stability of CO2 Sorbents: Poly(propylenimine) vs Poly(ethylenimine).

PubMed

Pang, Simon H; Lee, Li-Chen; Sakwa-Novak, Miles A; Lively, Ryan P; Jones, Christopher W

2017-03-15

Studies on aminopolymer/oxide composite materials for direct CO 2 capture from air have often focused on the prototypical poly(ethylenimine) (PEI) as the aminopolymer. However, it is known that PEI will oxidatively degrade at elevated temperatures. This degradation has been ascribed to the presence of secondary amines, which, when oxidized, lose their CO 2 capture capacity. Here, we demonstrate the use of small molecule poly(propylenimine) (PPI) in linear and dendritic architectures supported in silica as adsorbent materials for direct CO 2 capture from air. Regardless of amine loading or aminopolymer architecture, the PPI-based sorbents are found to be more efficient for CO 2 capture than PEI-based sorbents. Moreover, PPI is found to be more resistant to oxidative degradation than PEI, even while containing secondary amines, as supported by FTIR, NMR, and ESI-MS studies. These results suggest that PPI-based CO 2 sorbents may allow for longer sorbent working lifetimes due to an increased tolerance to sorbent regeneration conditions and suggest that the presence of secondary amines may not mean that all aminopolymers will oxidatively degrade.

Atmospheric CO2 capture for the artificial photosynthetic system

NASA Astrophysics Data System (ADS)

Nogalska, Adrianna; Zukowska, Adrianna; Garcia-Valls, Ricard

2017-11-01

The scope of these studies is to evaluate the ambient CO2 capture abilities of the membrane contactor system in the same conditions as leaves works during photosynthesis, such as ambient temperature, pressure and low CO2 concentration, where the only driving force is the concentration gradient. The polysulfone membrane was made by phase inversion process and characterized by ESEM micrographs which were used to determine the thickness, asymmetry and pore size. Besides, the porosity of the membrane was measured from the membrane and polysulfone density correlation and hydrophobicity was analyzed by contact angle measurements. Moreover, the compatibility of the membrane and absorbent solution was evaluated, in order to exclude wetting issues. The prepared membranes were introduced in a cross flow module and used as contactor between the CO2 and the potassium hydroxide solution, as absorbing media. The influence of the membrane thickness, absorbent stirring rate and absorption time, on CO2 capture were evaluated. The results show that the efficiency of our CO2 capture system is similar to stomatal carbon dioxide assimilation rate.

Evaluating metal-organic frameworks for post-combustion carbon dioxide capture via temperature swing adsorption

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mason, JA; Sumida, K; Herm, ZR

Two representative metal-organic frameworks, Zn4O(BTB)(2)(BTB3- = 1,3,5-benzenetribenzoate; MOF-177) and Mg-2(dobdc) (dobdc(4-) = 1,4-dioxido-2,5-benzenedicarboxylate; Mg-MOF-74, CPO-27-Mg), are evaluated in detail for their potential use in post-combustion CO2 capture via temperature swing adsorption (TSA). Low-pressure single-component CO2 and N-2 adsorption isotherms were measured every 10 degrees C from 20 to 200 degrees C, allowing the performance of each material to be analyzed precisely. In order to gain a more complete understanding of the separation phenomena and the thermodynamics of CO2 adsorption, the isotherms were analyzed using a variety of methods. With regard to the isosteric heat of CO2 adsorption, Mg-2(dobdc) exhibits anmore » abrupt drop at loadings approaching the saturation of the Mg2+ sites, which has significant implications for regeneration in different industrial applications. The CO2/N-2 selectivities were calculated using ideal adsorbed solution theory (IAST) for MOF-177, Mg-2(dobdc), and zeolite NaX, and working capacities were estimated using a simplified TSA model. Significantly, MOF-177 fails to exhibit a positive working capacity even at regeneration temperatures as high as 200 degrees C, while Mg-2(dobdc) reaches a working capacity of 17.6 wt% at this temperature. Breakthrough simulations were also performed for the three materials, demonstrating the superior performance of Mg-2(dobdc) over MOF-177 and zeolite NaX. These results show that the presence of strong CO2 adsorption sites is essential for a metal-organic framework to be of utility in post-combustion CO2 capture via a TSA process, and present a methodology for the evaluation of new metal-organic frameworks via analysis of single-component gas adsorption isotherms.« less

Influence of periodically changing oxidizing and reducing environment on sulfur capture under PFBC conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yrjas, P.; Hupa, M.

1997-12-31

In the literature it has been reported that sulfur capture with limestone (CaCO{sub 3}) under atmospheric fluidized bed combustion conditions reaches a maximum at about 850 C. Previously, the maximum has been attributed to the sintering of the sorbent particles which decreases the reactive surface area. Lately, also another explanation has been reported. In this case the sulfur capture decrease at higher temperatures was concluded to be due to fluctuating oxidizing/reducing conditions in the atmospheric combustor. In this paper the influence of alternating oxidizing/reducing conditions on SO{sub 2} capture at atmospheric and elevated pressure (15 bar) is reported. In themore » pressurized case, the CO{sub 2} partial pressure was kept high enough to prevent CaCO{sub 3} from calcining and therefore the CaSO{sub 4} would not form CaO but CaCO{sub 3} from calcining and therefore the CaSO{sub 4} would not form CaO but CaCO{sub 3} under reducing conditions. The experiments were done with a pressurized TGA by periodically changing the gas environment between oxidizing (O{sub 2}, SO{sub 2}, CO{sub 2} and N{sub 2}) and slightly reducing (CO, SO{sub 2}, CO{sub 2} and N{sub 2}) gas mixtures at different temperatures. The results showed that under normal pressure and slightly reducing conditions CaO formation from CaSO{sub 4} increased with temperature as expected. However, no significant amounts of CaCO{sub 3} were formed from CaSO{sub 4} at elevated pressure. It was also concluded that since the formation of CaO from CaSO{sub 4} was relatively slow it could not explain the sharp sulfur capture maximum at about 850 C. Therefore, it was assumed that the strongly reducing zones, where CaS thermodynamically is the stable compound, may play a more important role than the slightly reducing zones, concerning the sulfur capture in fluidized bed combustors.« less

Computational materials chemistry for carbon capture using porous materials

NASA Astrophysics Data System (ADS)

Sharma, Abhishek; Huang, Runhong; Malani, Ateeque; Babarao, Ravichandar

2017-11-01

Control over carbon dioxide (CO2) release is extremely important to decrease its hazardous effects on the environment such as global warming, ocean acidification, etc. For CO2 capture and storage at industrial point sources, nanoporous materials offer an energetically viable and economically feasible approach compared to chemisorption in amines. There is a growing need to design and synthesize new nanoporous materials with enhanced capability for carbon capture. Computational materials chemistry offers tools to screen and design cost-effective materials for CO2 separation and storage, and it is less time consuming compared to trial and error experimental synthesis. It also provides a guide to synthesize new materials with better properties for real world applications. In this review, we briefly highlight the various carbon capture technologies and the need of computational materials design for carbon capture. This review discusses the commonly used computational chemistry-based simulation methods for structural characterization and prediction of thermodynamic properties of adsorbed gases in porous materials. Finally, simulation studies reported on various potential porous materials, such as zeolites, porous carbon, metal organic frameworks (MOFs) and covalent organic frameworks (COFs), for CO2 capture are discussed.

Synthesis and characterization of low viscosity carbon dioxide binding organic liquids for flue gas clean up

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koech, Phillip K.; Malhotra, Deepika; Heldebrant, David J.

2015-01-01

Climate change is partly attributed to global anthropogenic carbon dioxide (CO2) emission to the atmosphere. These environmental effects can be mitigated by CO2 capture, utilization and storage. Alkanolamine solvents, such as monoethanolamine (MEA), which bind CO2 as carbamates or bicarbonate salts are used for CO2 capture in niche applications. These solvents consist of approximately 30 wt% of MEA in water, exhibiting a low, CO2-rich viscosity, fast kinetics and favorable thermodynamics. However, these solvents have low CO2 capacity and high heat capacity of water, resulting in prohibitively high costs of thermal solvent regeneration. Effective capture of the enormous amounts of CO2more » produced by coal-fired plants requires a material with high CO2 capacity and low regeneration energy requirements. To this end, several water-lean transformational solvents systems have been developed in order to reduce these energy penalties. These technologies include nano-material organic hybrids (NOHMs), task-specific, protic and conventional ionic liquids, phase change solvents. As part of an ongoing program in our group, we have developed new water lean transformational solvents known as CO2 binding organic liquids (CO2BOLs) which have the potential to be energy efficient CO2 capture solvents. These solvents, also known as switchable ionic liquids meaning, are organic solvents that can reversibly transform from non- ionic to ionic form and back. The zwitterionic state in these liquids is formed when low polarity non-ionic alkanolguanidines or alkanolamidines react with CO2 or SO2 to form ionic liquids with high polarity. These polar ionic liquids can be thermally converted to the less polar non-ionic solvent by releasing CO2.« less

Global evaluation of particulate organic carbon flux parameterizations and implications for atmospheric pCO2

NASA Astrophysics Data System (ADS)

Gloege, Lucas; McKinley, Galen A.; Mouw, Colleen B.; Ciochetto, Audrey B.

2017-07-01

The shunt of photosynthetically derived particulate organic carbon (POC) from the euphotic zone and deep remineralization comprises the basic mechanism of the "biological carbon pump." POC raining through the "twilight zone" (euphotic depth to 1 km) and "midnight zone" (1 km to 4 km) is remineralized back to inorganic form through respiration. Accurately modeling POC flux is critical for understanding the "biological pump" and its impacts on air-sea CO2 exchange and, ultimately, long-term ocean carbon sequestration. Yet commonly used parameterizations have not been tested quantitatively against global data sets using identical modeling frameworks. Here we use a single one-dimensional physical-biogeochemical modeling framework to assess three common POC flux parameterizations in capturing POC flux observations from moored sediment traps and thorium-234 depletion. The exponential decay, Martin curve, and ballast model are compared to data from 11 biogeochemical provinces distributed across the globe. In each province, the model captures satellite-based estimates of surface primary production within uncertainties. Goodness of fit is measured by how well the simulation captures the observations, quantified by bias and the root-mean-square error and displayed using "target diagrams." Comparisons are presented separately for the twilight zone and midnight zone. We find that the ballast hypothesis shows no improvement over a globally or regionally parameterized Martin curve. For all provinces taken together, Martin's b that best fits the data is [0.70, 0.98]; this finding reduces by at least a factor of 3 previous estimates of potential impacts on atmospheric pCO2 of uncertainty in POC export to a more modest range [-16 ppm, +12 ppm].

Integration of CO2 Capture and Mineral Carbonation by Using Recyclable Ammonium Salts

PubMed Central

Wang, Xiaolong; Maroto-Valer, M Mercedes

2011-01-01

A new approach to capture and store CO2 by mineral carbonation using recyclable ammonium salts was studied. This process integrates CO2 capture with mineral carbonation by employing NH3, NH4HSO4, and NH4HCO3 in the capture, mineral dissolution, and carbonation steps, respectively. NH4HSO4 and NH3 can then be regenerated by thermal decomposition of (NH4)2SO4. The use of NH4HCO3 as the source of CO2 can avoid desorption and compression of CO2. The mass ratio of Mg/NH4HCO3/NH3 is the key factor controlling carbonation and the optimum ratio of 1:4:2 gives a conversion of Mg ions to hydromagnesite of 95.5 %. Thermogravimetric analysis studies indicated that the regeneration efficiency of NH4HSO4 and NH3 in this process is 95 %. The mass balance of the process shows that about 2.63 tonnes of serpentine, 0.12 tonnes of NH4HSO4, 7.48 tonnes of NH4HCO3, and 0.04 tonnes of NH3 are required to sequester 1 tonne of CO2 as hydromagnesite. PMID:21732542

High CO2 absorption capacity by chemisorption at cations and anions in choline-based ionic liquids.

PubMed

Bhattacharyya, Shubhankar; Filippov, Andrei; Shah, Faiz Ullah

2017-11-29

The effect of CO 2 absorption on the aromaticity and hydrogen bonding in ionic liquids is investigated. Five different ionic liquids with choline based cations and aprotic N-heterocyclic anions were synthesized. Purity and structures of the synthesized ionic liquids were characterized by 1 H and 13 C NMR spectroscopy. CO 2 capture performance was studied at 20 °C and 40 °C under three different pressures (1, 3, 6 bar). The IL [N 1,1,6,2OH ][4-Triz] showed the highest CO 2 capture capacity (28.6 wt%, 1.57 mol of CO 2 per mol of the IL, 6.48 mol of CO 2 per kg of the ionic liquid) at 20 °C and 1 bar. The high CO 2 capture capacity of the [N 1,1,6,2OH ][4-Triz] IL is due to the formation of carbonic acid (-OCO 2 H) together with carbamate by participation of the -OH group of the [N 1,1,6,2OH ] + cation in the CO 2 capture process. The structure of the adduct formed by CO 2 reaction with the IL [N 1,1,6,2OH ][4-Triz] was probed by using IR, 13 C NMR and 1 H- 13 C HMBC NMR experiments utilizing 13 C labeled CO 2 gas. 1 H and 13 C PFG NMR studies were performed before and after CO 2 absorption to explore the effect of cation-anion structures on the microscopic ion dynamics in ILs. The ionic mobility was significantly increased after CO 2 reaction due to lowering of aromaticity in the case of ILs with aromatic N-heterocyclic anions.

Where does the carbon go? A model–data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites

PubMed Central

De Kauwe, Martin G; Medlyn, Belinda E; Zaehle, Sönke; Walker, Anthony P; Dietze, Michael C; Wang, Ying-Ping; Luo, Yiqi; Jain, Atul K; El-Masri, Bassil; Hickler, Thomas; Wårlind, David; Weng, Ensheng; Parton, William J; Thornton, Peter E; Wang, Shusen; Prentice, I Colin; Asao, Shinichi; Smith, Benjamin; McCarthy, Heather R; Iversen, Colleen M; Hanson, Paul J; Warren, Jeffrey M; Oren, Ram; Norby, Richard J

2014-01-01

Elevated atmospheric CO2 concentration (eCO2) has the potential to increase vegetation carbon storage if increased net primary production causes increased long-lived biomass. Model predictions of eCO2 effects on vegetation carbon storage depend on how allocation and turnover processes are represented. We used data from two temperate forest free-air CO2 enrichment (FACE) experiments to evaluate representations of allocation and turnover in 11 ecosystem models. Observed eCO2 effects on allocation were dynamic. Allocation schemes based on functional relationships among biomass fractions that vary with resource availability were best able to capture the general features of the observations. Allocation schemes based on constant fractions or resource limitations performed less well, with some models having unintended outcomes. Few models represent turnover processes mechanistically and there was wide variation in predictions of tissue lifespan. Consequently, models did not perform well at predicting eCO2 effects on vegetation carbon storage. Our recommendations to reduce uncertainty include: use of allocation schemes constrained by biomass fractions; careful testing of allocation schemes; and synthesis of allocation and turnover data in terms of model parameters. Data from intensively studied ecosystem manipulation experiments are invaluable for constraining models and we recommend that such experiments should attempt to fully quantify carbon, water and nutrient budgets. PMID:24844873

Potential of two-stage membrane system with recycle stream for CO{sub 2} capture from postcombustion gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dongxiao Yang; Zhi Wang; Jixiao Wang

2009-09-15

In order to restrict greenhouse gases emissions, CO{sub 2} should be captured from the postcombustion gas for further treatment, for example, geosequestration. In this work, the separation performance of the two-stage membrane system with a recycle stream was investigated using the cross-flow model. For larger CO{sub 2}/N{sub 2} selectivities that can be achieved in the lab, for example, selectivity of 52, the separation target of CO{sub 2} purity >95% and CO{sub 2} recovery >90% can be fulfilled by the two-stage system. The process cost of the two-stage membrane process was investigated. There is an optimum pressure ratio with which themore » capital cost and the energy cost can be balanced to minimize the total cost. Using the optimum pressure ratios and efficient membranes, the total cost of the two-stage system can be reduced to a range that is competitive with the process cost of the traditional chemical absorption method. For example, with feed compression applied, the total cost of the two-stage membrane system using the membrane with CO{sub 2}/N{sub 2} selectivity of 52 and CO{sub 2} permeance of 3.12 x 10{sup -3} m{sup 3} (STP) m{sup -2} s{sup -1} MPa{sup -1} is estimated to be $47.9/(ton CO{sub 2} recovered). 22 refs., 11 figs., 3 tabs.« less

Biorefineries of carbon dioxide: From carbon capture and storage (CCS) to bioenergies production.

PubMed

Cheah, Wai Yan; Ling, Tau Chuan; Juan, Joon Ching; Lee, Duu-Jong; Chang, Jo-Shu; Show, Pau Loke

2016-09-01

Greenhouse gas emissions have several adverse environmental effects, like pollution and climate change. Currently applied carbon capture and storage (CCS) methods are not cost effective and have not been proven safe for long term sequestration. Another attractive approach is CO2 valorization, whereby CO2 can be captured in the form of biomass via photosynthesis and is subsequently converted into various form of bioenergy. This article summarizes the current carbon sequestration and utilization technologies, while emphasizing the value of bioconversion of CO2. In particular, CO2 sequestration by terrestrial plants, microalgae and other microorganisms are discussed. Prospects and challenges for CO2 conversion are addressed. The aim of this review is to provide comprehensive knowledge and updated information on the current advances in biological CO2 sequestration and valorization, which are essential if this approach is to achieve environmental sustainability and economic feasibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lai, Canhai; Xu, Zhijie; Li, Tingwen

In virtual design and scale up of pilot-scale carbon capture systems, the coupled reactive multiphase flow problem must be solved to predict the adsorber’s performance and capture efficiency under various operation conditions. This paper focuses on the detailed computational fluid dynamics (CFD) modeling of a pilot-scale fluidized bed adsorber equipped with vertical cooling tubes. Multiphase Flow with Interphase eXchanges (MFiX), an open-source multiphase flow CFD solver, is used for the simulations with custom code to simulate the chemical reactions and filtered models to capture the effect of the unresolved details in the coarser mesh for simulations with reasonable simulations andmore » manageable computational effort. Previously developed two filtered models for horizontal cylinder drag, heat transfer, and reaction kinetics have been modified to derive the 2D filtered models representing vertical cylinders in the coarse-grid CFD simulations. The effects of the heat exchanger configurations (i.e., horizontal or vertical) on the adsorber’s hydrodynamics and CO2 capture performance are then examined. The simulation result subsequently is compared and contrasted with another predicted by a one-dimensional three-region process model.« less

Enhanced Adsorption Efficiency through Materials Design for Direct Air Capture over Supported Polyethylenimine.

PubMed

Sayari, Abdelhamid; Liu, Qing; Mishra, Prashant

2016-10-06

Until recently, carbon capture and sequestration (CCS) was regarded as the most promising technology to address the alarming increase in the concentration of anthropogenic CO 2 in the atmosphere. There is now an increasing interest in carbon capture and utilization (CCU). In this context, the capture of CO 2 from air is an ideal solution to supply pure CO 2 wherever it is needed. Here, we describe innovative materials for direct air capture (DAC) with unprecedented efficiency. Polyethylenimine (PEI) was supported on PME, which is an extra-large-pore silica (pore-expanded MCM-41) with its internal surfaces fully covered by a uniform layer of readily accessible C 16 chains from cetyltrimethylammonium (CTMA + ) cations. The CTMA + layer plays a key role in enhancing the amine efficiency toward dry or humid ultradilute CO 2 (400 ppm CO 2 /N 2 ) to unprecedented levels. At the same PEI content, the amine efficiency of PEI/PME was two to four times higher than that of the corresponding calcined mesoporous silica loaded with PEI or with different combinations of C 16 chains and PEI. Under humid conditions, the amine efficiency of 40 wt % PEI/PME reached 7.31 mmolCO2 /g PEI , the highest ever reported for any supported PEI in the presence of 400 ppm CO 2 . Thus, amine accessibility, which reflects both the state of PEI dispersion and the adsorption efficiency, is intimately associated with the molecular design of the adsorbent. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Assessment of CO2 Storage Potential in Naturally Fractured Reservoirs With Dual-Porosity Models

NASA Astrophysics Data System (ADS)

March, Rafael; Doster, Florian; Geiger, Sebastian

2018-03-01

Naturally Fractured Reservoirs (NFR's) have received little attention as potential CO2 storage sites. Two main facts deter from storage projects in fractured reservoirs: (1) CO2 tends to be nonwetting in target formations and capillary forces will keep CO2 in the fractures, which typically have low pore volume; and (2) the high conductivity of the fractures may lead to increased spatial spreading of the CO2 plume. Numerical simulations are a powerful tool to understand the physics behind brine-CO2 flow in NFR's. Dual-porosity models are typically used to simulate multiphase flow in fractured formations. However, existing dual-porosity models are based on crude approximations of the matrix-fracture fluid transfer processes and often fail to capture the dynamics of fluid exchange accurately. Therefore, more accurate transfer functions are needed in order to evaluate the CO2 transfer to the matrix. This work presents an assessment of CO2 storage potential in NFR's using dual-porosity models. We investigate the impact of a system of fractures on storage in a saline aquifer, by analyzing the time scales of brine drainage by CO2 in the matrix blocks and the maximum CO2 that can be stored in the rock matrix. A new model to estimate drainage time scales is developed and used in a transfer function for dual-porosity simulations. We then analyze how injection rates should be limited in order to avoid early spill of CO2 (lost control of the plume) on a conceptual anticline model. Numerical simulations on the anticline show that naturally fractured reservoirs may be used to store CO2.

Fixing atmospheric CO2 by environment adaptive sorbent and renewable energy

NASA Astrophysics Data System (ADS)

Wang, T.; Liu, J.; Ge, K.; Fang, M.

2014-12-01

Fixing atmospheric CO2, followed by geologic storage in remote areas is considered an environmentally secure approach to climate mitigation. A moisture swing sorbent was investigated in the laboratory for CO2 capture at a remote area with humid and windy conditions. The energy requirement of moisture swing absorption could be greatly reduced compared to that of traditional high-temperature thermal swing, by assuming that the sorbent can be naturally dried and regenerated at ambient conditions. However, for currently developed moisture swing materials, the CO2 capacity would drop significantly at high relative humidity. The CO2 capture amount can be reduced by the poor thermodynamics and kinetics at high relative humidity or low temperature. Similar challenges also exist for thermal or vacuum swing sorbents. Developing sorbent materials which adapt to specific environments, such as high humidity or low temperature, can ensure sufficient capture capacity on the one hand, and realize better economics on the other hand (Figure 1) .An environment adaptive sorbent should have the abilities of tunable capacity and fast kinetics at extreme conditions, such as high humidity or low temperature. In this presentation, the possibility of tuning CO2 absorption capacity of a polymerized ionic liquid material is discussed. The energy requirement evaluation shows that tuning the CO2 binding energy of sorbent, rather than increasing the temperature or reducing the humidity of air, could be much more economic. By determining whether the absorption process is controlled by physical diffusion controlled or chemical reaction, an effective approach to fast kinetics at extreme conditions is proposed. A shrinking core model for mass transfer kinetics is modified to cope with the relatively poor kinetics of air capture. For the studied sample which has a heterogeneous structure, the kinetic analysis indicates a preference of sorbent particle size optimization, rather than support layer optimization. Chemical reaction kinetics could be enhanced by stronger binding energy or higher temperature. However, the total kinetics can only be significantly improved by chemical reaction enhancement if the physical diffusion is fast enough.

Thermodynamic and Kinetic Response of Microbial Reactions to High CO2.

PubMed

Jin, Qusheng; Kirk, Matthew F

2016-01-01

Geological carbon sequestration captures CO 2 from industrial sources and stores the CO 2 in subsurface reservoirs, a viable strategy for mitigating global climate change. In assessing the environmental impact of the strategy, a key question is how microbial reactions respond to the elevated CO 2 concentration. This study uses biogeochemical modeling to explore the influence of CO 2 on the thermodynamics and kinetics of common microbial reactions in subsurface environments, including syntrophic oxidation, iron reduction, sulfate reduction, and methanogenesis. The results show that increasing CO 2 levels decreases groundwater pH and modulates chemical speciation of weak acids in groundwater, which in turn affect microbial reactions in different ways and to different extents. Specifically, a thermodynamic analysis shows that increasing CO 2 partial pressure lowers the energy available from syntrophic oxidation and acetoclastic methanogenesis, but raises the available energy of microbial iron reduction, hydrogenotrophic sulfate reduction and methanogenesis. Kinetic modeling suggests that high CO 2 has the potential of inhibiting microbial sulfate reduction while promoting iron reduction. These results are consistent with the observations of previous laboratory and field studies, and highlight the complexity in microbiological responses to elevated CO 2 abundance, and the potential power of biogeochemical modeling in evaluating and quantifying these responses.

Thermodynamic and Kinetic Response of Microbial Reactions to High CO2

PubMed Central

Jin, Qusheng; Kirk, Matthew F.

2016-01-01

Geological carbon sequestration captures CO2 from industrial sources and stores the CO2 in subsurface reservoirs, a viable strategy for mitigating global climate change. In assessing the environmental impact of the strategy, a key question is how microbial reactions respond to the elevated CO2 concentration. This study uses biogeochemical modeling to explore the influence of CO2 on the thermodynamics and kinetics of common microbial reactions in subsurface environments, including syntrophic oxidation, iron reduction, sulfate reduction, and methanogenesis. The results show that increasing CO2 levels decreases groundwater pH and modulates chemical speciation of weak acids in groundwater, which in turn affect microbial reactions in different ways and to different extents. Specifically, a thermodynamic analysis shows that increasing CO2 partial pressure lowers the energy available from syntrophic oxidation and acetoclastic methanogenesis, but raises the available energy of microbial iron reduction, hydrogenotrophic sulfate reduction and methanogenesis. Kinetic modeling suggests that high CO2 has the potential of inhibiting microbial sulfate reduction while promoting iron reduction. These results are consistent with the observations of previous laboratory and field studies, and highlight the complexity in microbiological responses to elevated CO2 abundance, and the potential power of biogeochemical modeling in evaluating and quantifying these responses. PMID:27909425

Developing multi-tracer approaches to constrain the parameterisation of leaf and soil CO2 and H2O exchange in land surface models

NASA Astrophysics Data System (ADS)

Ogée, Jerome; Wehr, Richard; Commane, Roisin; Launois, Thomas; Meredith, Laura; Munger, Bill; Nelson, David; Saleska, Scott; Zahniser, Mark; Wofsy, Steve; Wingate, Lisa

2016-04-01

The net flux of carbon dioxide between the land surface and the atmosphere is dominated by photosynthesis and soil respiration, two of the largest gross CO2 fluxes in the carbon cycle. More robust estimates of these gross fluxes could be obtained from the atmospheric budgets of other valuable tracers, such as carbonyl sulfide (COS) or the carbon and oxygen isotope compositions (δ13C and δ18O) of atmospheric CO2. Over the past decades, the global atmospheric flask network has measured the inter-annual and intra-annual variations in the concentrations of these tracers. However, knowledge gaps and a lack of high-resolution multi-tracer ecosystem-scale measurements have hindered the development of process-based models that can simulate the behaviour of each tracer in response to environmental drivers. We present novel datasets of net ecosystem COS, 13CO2 and CO18O exchange and vertical profile data collected over 3 consecutive growing seasons (2011-2013) at the Harvard forest flux site. We then used the process-based model MuSICA (multi-layer Simulator of the Interactions between vegetation Canopy and the Atmosphere) to include the transport, reaction, diffusion and production of each tracer within the forest and exchanged with the atmosphere. Model simulations over the three years captured well the impact of diurnally and seasonally varying environmental conditions on the net ecosystem exchange of each tracer. The model also captured well the dynamic vertical features of tracer behaviour within the canopy. This unique dataset and model sensitivity analysis highlights the benefit in the collection of multi-tracer high-resolution field datasets and the developement of multi-tracer land surface models to provide valuable constraints on photosynthesis and respiration across scales in the near future.

C3 and C4 biomass allocation responses to elevated CO2 and nitrogen: contrasting resource capture strategies

USGS Publications Warehouse

White, K.P.; Langley, J.A.; Cahoon, D.R.; Megonigal, J.P.

2012-01-01

Plants alter biomass allocation to optimize resource capture. Plant strategy for resource capture may have important implications in intertidal marshes, where soil nitrogen (N) levels and atmospheric carbon dioxide (CO2) are changing. We conducted a factorial manipulation of atmospheric CO2 (ambient and ambient + 340 ppm) and soil N (ambient and ambient + 25 g m-2 year-1) in an intertidal marsh composed of common North Atlantic C3 and C4 species. Estimation of C3 stem turnover was used to adjust aboveground C3 productivity, and fine root productivity was partitioned into C3-C4 functional groups by isotopic analysis. The results suggest that the plants follow resource capture theory. The C3 species increased aboveground productivity under the added N and elevated CO2 treatment (P 2 alone. C3 fine root production decreased with added N (P 2 (P = 0.0481). The C4 species increased growth under high N availability both above- and belowground, but that stimulation was diminished under elevated CO2. The results suggest that the marsh vegetation allocates biomass according to resource capture at the individual plant level rather than for optimal ecosystem viability in regards to biomass influence over the processes that maintain soil surface elevation in equilibrium with sea level.

Microporous metal organic framework [M2(hfipbb)2(ted)] (M=Zn, Co; H2hfipbb=4,4-(hexafluoroisopropylidene)-bis(benzoic acid); ted=triethylenediamine): Synthesis, structure analysis, pore characterization, small gas adsorption and CO2/N2 separation properties

NASA Astrophysics Data System (ADS)

Xu, William W.; Pramanik, Sanhita; Zhang, Zhijuan; Emge, Thomas J.; Li, Jing

2013-04-01

Carbon dioxide is a greenhouse gas that is a major contributor to global warming. Developing methods that can effectively capture CO2 is the key to reduce its emission to the atmosphere. Recent research shows that microporous metal organic frameworks (MOFs) are emerging as a promising family of adsorbents that may be promising for use in adsorption based capture and separation of CO2 from power plant waste gases. In this work we report the synthesis, crystal structure analysis and pore characterization of two microporous MOF structures, [M2(hfipbb)2(ted)] (M=Zn (1), Co (2); H2hfipbb=4,4-(hexafluoroisopropylidene)-bis(benzoic acid); ted=triethylenediamine). The CO2 and N2 adsorption experiments and IAST calculations are carried out on [Zn2(hfipbb)2(ted)] under conditions that mimic post-combustion flue gas mixtures emitted from power plants. The results show that the framework interacts with CO2 strongly, giving rise to relatively high isosteric heats of adsorption (up to 28 kJ/mol), and high adsorption selectivity for CO2 over N2, making it promising for capturing and separating CO2 from CO2/N2 mixtures.

Amine-impregnated silica monolith with a hierarchical pore structure: enhancement of CO2 capture capacity.

PubMed

Chen, Chao; Yang, Seung-Tae; Ahn, Wha-Seung; Ryoo, Ryong

2009-06-28

A polyethylenimine-impregnated hierarchical silica monolith exhibited significantly higher CO(2) capturing capacity than other silica-supported amine sorbents, and produced a reversible and durable sorption performance.

Spray‐Dried Sodium Zirconate: A Rapid Absorption Powder for CO2 Capture with Enhanced Cyclic Stability

PubMed Central

Bamiduro, Faith; Ji, Guozhao; Brown, Andy P.; Dupont, Valerie A.

2017-01-01

Abstract Improved powders for capturing CO2 at high temperatures are required for H2 production using sorption‐enhanced steam reforming. Here, we examine the relationship between particle structure and carbonation rate for two types of Na2ZrO3 powders. Hollow spray‐dried microgranules with a wall thickness of 100–300 nm corresponding to the dimensions of the primary acetate‐derived particles gave about 75 wt % theoretical CO2 conversion after a process‐relevant 5 min exposure to 15 vol % CO2. A conventional powder prepared by solid‐state reaction carbonated more slowly, achieving only 50 % conversion owing to a greater proportion of the reaction requiring bulk diffusion through the densely agglomerated particles. The hollow granular structure of the spray‐dried powder was retained postcarbonation but chemical segregation resulted in islands of an amorphous Na‐rich phase (Na2CO3) within a crystalline ZrO2 particle matrix. Despite this phase separation, the reverse reaction to re‐form Na2ZrO3 could be achieved by heating each powder to 900 °C in N2 (no dwell time). This resulted in a very stable multicycle performance in 40 cycle tests using thermogravimetric analysis for both powders. Kinetic analysis of thermogravimetric data showed the carbonation process fits an Avrami–Erofeyev 2 D nucleation and nuclei growth model, consistent with microstructural evidence of a surface‐driven transformation. Thus, we demonstrate that spray drying is a viable processing route to enhance the carbon capture performance of Na2ZrO3 powder. PMID:28371521

Novel Inorganic/Polymer Composite Membranes for CO 2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ho, W.S. Winston; Dutta, Prabir K.; Schmit, Steve J.

The objective of this project is to develop a cost-effective design and manufacturing process for new membrane modules that capture CO 2 from flue gas in coal-fired power plants. The membrane consisted of a thin selective layer including inorganic (zeolite) embedded in a polymer structure so that it can be made in a continuous manufacturing process. The membrane was incorporated in spiral-wound modules for the field test with actual flue gas at the National Carbon Capture Center (NCCC) in Wilsonville, AL and bench scale tests with simulated flue gas at the Ohio State University (OSU). Using the modules for post-combustionmore » CO 2 capture is expected to achieve the DOE target of $40/tonne CO 2 captured (in 2007 dollar) for 2025. Membranes with the amine-containing polymer cover layer on zeolite-Y (ZY) nanoparticles deposited on the polyethersulfone (PES) substrate were successfully synthesized. The membranes showed a high CO 2 permeance of about 1100 GPU (gas permeation unit, 1 GPU = 10 -6 cm 3 (STP)/(cm 2 • s • cm Hg), 3000 GPU = 10-6 mol/(m 2 • s • Pa)) with a high CO 2/N 2 selectivity of > 200 at the typical flue gas conditions at 57°C (about 17% water vapor in feed gas) and > 1400 GPU CO 2 permeance with > 500 CO 2/N 2 selectivity at 102°C (~ 80% water vapor). The synthesis of ZY nanoparticles was successfully scaled up, and the pilot-scale membranes were also successfully fabricated using the continuous membrane machine at OSU. The transport performance of the pilot-scale membranes agreed reasonably well with the lab-scale membranes. The results from both the lab-scale and scale-up membranes were used for the techno-economic analysis. The scale-up membranes were fabricated into prototype spiral-wound membrane modules for continuous testing with simulated or real flue gas. For real flue gas testing, we worked with NCCC, in consultation with TriSep Corporation, Gradient Technology and American Electric Power (AEP). The membrane module demonstrated > 800 GPU of CO 2 permeance and > 150 CO 2/N 2 selectivity when tested with real flue gas at NCCC. The results obtained were used to update the techno-economic analysis. In addition, the EH&S assessment of the membranes for post-combustion CO 2 capture was conducted.« less

Humidity-swing mechanism for CO2 capture from ambient air.

PubMed

Yang, Hao; Singh, Manmilan; Schaefer, Jacob

2018-05-10

A humidity-swing polymeric sorbent captures CO2 from ambient air at room temperature simply by changing the humidity level. To date there has been no direct experimental evidence to characterize the chemical mechanism for this process. In this report we describe the use of solid-state NMR to study the humidity-swing CO2 absorption/desorption cycle directly. We find that at low humidity levels CO2 is absorbed as HCO3-. At high humidity levels, HCO3- is replaced by hydrated OH- and the absorbed CO2 is released.

Co-location of air capture, sub-ocean CO2 storage and energy production on the Kerguelen plateau

NASA Astrophysics Data System (ADS)

Goldberg, D.; Han, P.; Lackner, K.; Wang, T.

2011-12-01

How can carbon capture and storage activities be sustained from an energy perspective while keeping the entire activity out of sight and away from material risk and social refrain near populated areas? In light of reducing the atmospheric CO2 level to mitigate its effect on climate change, the combination of new air-capture technologies and large offshore storage reservoirs, supplemented by carbon neutral renewable energy, could address both of these engineering and public policy concerns. Because CO2 mixes rapidly in the atmosphere, air capture scrubbers could be located anywhere in the world. Although the power requirements for this technology may reduce net efficiencies, the local availability of carbon-neutral renewable energy for this purpose would eliminate some net energy loss. Certain locations where wind speeds are high and steady, such as those observed at high latitude and across the open ocean, appeal as carbon-neutral energy sources in close proximity to immense and secure reservoirs for geological sequestration of captured CO2. In particular, sub-ocean basalt flows are vast and carry minimal risks of leakage and damages compared to on-land sites. Such implementation of a localized renewable energy source coupled with carbon capture and storage infrastructure could result in a global impact of lowered CO2 levels. We consider an extreme location on the Kerguelen plateau in the southern Indian Ocean, where high wind speeds and basalt storage reservoirs are both plentiful. Though endowed with these advantages, this mid-ocean location incurs clear material and economic challenges due to its remoteness and technological challenges for CO2 capture due to constant high humidity. We study the wind energy-air capture power balance and consider related factors in the feasibility of this location for carbon capture and storage. Other remote oceanic sites where steady winds blow and near large geological reservoirs may be viable as well, although all would require extensive research. Using these mitigation technologies in combination may offer a pivotal option for reducing atmospheric carbon to pre-industrial levels with minimal human risk or inconvenience.

Heat recovery from sorbent-based CO.sub.2 capture

DOEpatents

Jamal, Aqil; Gupta, Raghubir P

2015-03-10

The present invention provides a method of increasing the efficiency of exothermic CO.sub.2 capture processes. The method relates to withdrawing heat generated during the exothermic capture of CO.sub.2 with various sorbents via heat exchange with a working fluid. The working fluid is provided at a temperature and pressure such that it is in the liquid state, and has a vaporization temperature in a range such that the heat arising from the reaction of the CO.sub.2 and the sorbent causes a phase change from liquid to vapor state in whole or in part and transfers heat from to the working fluid. The resulting heated working fluid may subsequently be used to generate power.

Pre-combustion CO2 capture by transition metal ions embedded in phthalocyanine sheets

NASA Astrophysics Data System (ADS)

Lü, Kun; Zhou, Jian; Zhou, Le; Chen, X. S.; Chan, Siew Hwa; Sun, Qiang

2012-06-01

Transition metal (TM) embedded two-dimensional phthalocyanine (Pc) sheets have been recently synthesized in experiments [M. Abel, S. Clair, O. Ourdjini, M. Mossoyan, and L. Porte, J. Am. Chem. Soc. 133, 1203 (2010)], 10.1021/ja108628r, where the transition metal ions are uniformly distributed in porous structures, providing the possibility of capturing gas molecules. Using first principles and grand canonical Monte Carlo simulations, TMPc sheets (TM = Sc, Ti, and Fe) are studied for pre-combustion CO2 capture by considering the adsorptions of H2/CO2 gas mixtures. It is found that ScPc sheet shows a good selectivity for CO2, and the excess uptake capacity of single-component CO2 on ScPc sheet at 298 K and 50 bar is found to be 2949 mg/g, larger than that of any other reported porous materials. Furthermore, electrostatic potential and natural bond orbital analyses are performed to reveal the underlying interaction mechanisms, showing that electrostatic interactions as well as the donation and back donation of electrons between the transition metal ions and the CO2 molecules play a key role in the capture.

Potassium-based sorbents from fly ash for high-temperature CO2 capture.

PubMed

Sanna, Aimaro; Maroto-Valer, M Mercedes

2016-11-01

Potassium-fly ash (K-FA) sorbents were investigated for high-temperature CO 2 sorption. K-FAs were synthesised using coal fly ash as source of silica and aluminium. The synthesised materials were also mixed with Li 2 CO 3 and Ca(OH) 2 to evaluate their effect on CO 2 capture. Temperature strongly affected the performance of the K-FA sorbents, resulting in a CO 2 uptake of 1.45 mmol CO 2 /g sorbent for K-FA 1:1 at 700 °C. The CO 2 sorption was enhanced by the presence of Li 2 CO 3 (10 wt%), with the K-FA 1:1 capturing 2.38 mmol CO 2 /g sorbent at 700 °C in 5 min. This sorption was found to be similar to previously developed Li-Na-FA (2.54 mmol/g) and Li-FA (2.4 mmol/g) sorbents. The presence of 10 % Li 2 CO 3 also accelerated sorption and desorption. The results suggest that the increased uptake of CO 2 and faster reaction rates in presence of K-FA can be ascribed to the formation of K-Li eutectic phase, which favours the diffusion of potassium and CO 2 in the material matrix. The cyclic experiments showed that the K-FA materials maintained stable CO 2 uptake and reaction rates over 10 cycles.

Mechanism Study of Carbon Dioxide Capture from Ambient Air by Hydration Energy Variation

NASA Astrophysics Data System (ADS)

Shi, X.; Lackner, K. S.

2014-12-01

Hydration of neutral and ionic species on solid interfaces plays an important role in a wide range of natural and engineered processes within energy systems as well as biological and environmental systems. Various chemical reactions are significantly enhanced, both in the rate and the extent of the reaction, because of water molecules present or absent at the interface. A novel technology for carbon dioxide capture, driven by the free energy difference between more or less hydrated states of an anionic exchange resin is studied for a new approach to absorb CO2 from ambient air. For these materials the affinity to CO2 is dramatically lowered as the availability of water is increased. This makes it possible to absorb CO2 from air in a dry environment and release it at two orders of magnitude larger partial pressures in a wet environment. While the absorption process and the thermodynamic properties of air capture via ion exchange resins have been demonstrated, the underlying physical mechanisms remain to be understood. In order to rationally design better sorbent materials, the present work elucidates through molecular dynamics and quantum mechanical modeling the energy changes in the carbonate, bicarbonate and hydroxide ions that are induced by hydration, and how these changes affect sorbent properties. A methodology is developed to determine the free energy change during carbonate ion hydrolysis changes with different numbers of water molecules present. This makes it possible to calculate the equilibrium in the reaction CO3--•nH2O ↔ HCO3- • m1H2O + OH- • m2H2O + (n - 1 - m1 - m2)H2O Molecular dynamics models are used to calculate free energies of hydration for the CO32- ion, the HCO3- ion, and the OH- ion as function of the amount of water that is present. A quantum mechanical model is employed to study the equilibrium of the reaction Na2CO3 + H2O ↔ NaHCO3 + NaOHin a vacuum and at room temperature. The computational analysis of the free energy of hydration reveals that in an ionic exchange resin the equilibrium between carbonate, bicarbonate and hydroxide favors a combination of bicarbonate and hydroxide over the formation of carbonate ions. In the case of low water content, the presence of a large number of hydroxide ions increases the affinity of the resin to CO2.

CO2 capture by means of an enzyme-based reactor

NASA Technical Reports Server (NTRS)

Cowan, R. M.; Ge, J-J; Qin, Y-J; McGregor, M. L.; Trachtenberg, M. C.

2003-01-01

We report a means for efficient and selective extraction of carbon dioxide (CO(2)) at low to medium concentration from mixed gas streams. CO(2) capture was accomplished by use of a novel enzyme-based, facilitated transport contained liquid membrane (EBCLM) reactor. The parametric studies we report explore both structural and operational parameters of this design. The structural parameters include carbonic anhydrase (CA) concentration, buffer concentration and pH, and liquid membrane thickness. The operational parameters are temperature, humidity of the inlet gas stream, and CO(2) concentration in the feed stream. The data show that this system effectively captures CO(2) over the range 400 ppm to at least 100,000 ppm, at or around ambient temperature and pressure. In a single pass across this homogeneous catalyst design, given a feed of 0.1% CO(2), the selectivity of CO(2) versus N(2) is 1,090 : 1 and CO(2) versus O(2) is 790 :1. CO(2) permeance is 4.71 x 10(-8) molm(-2) Pa(-1) sec(-1). The CLM design results in a system that is very stable even in the presence of dry feed and sweep gases.

Sequential capture of CO2 and SO2 in a pressurized TGA simulating FBC conditions.

PubMed

Sun, Ping; Grace, John R; Lim, C Jim; Anthony, Edward J

2007-04-15

Four FBC-based processes were investigated as possible means of sequentially capturing SO2 and CO2. Sorbent performance is the key to their technical feasibility. Two sorbents (a limestone and a dolomite) were tested in a pressurized thermogravimetric analyzer (PTGA). The sorbent behaviors were explained based on complex interaction between carbonation, sulfation, and direct sulfation. The best option involved using limestone or dolomite as a SO2-sorbent in a FBC combustor following cyclic CO2 capture. Highly sintered limestone is a good sorbent for SO2 because of the generation of macropores during calcination/carbonation cycling.

Economics of carbon dioxide capture and utilization-a supply and demand perspective.

PubMed

Naims, Henriette

2016-11-01

Lately, the technical research on carbon dioxide capture and utilization (CCU) has achieved important breakthroughs. While single CO 2 -based innovations are entering the markets, the possible economic effects of a large-scale CO 2 utilization still remain unclear to policy makers and the public. Hence, this paper reviews the literature on CCU and provides insights on the motivations and potential of making use of recovered CO 2 emissions as a commodity in the industrial production of materials and fuels. By analyzing data on current global CO 2 supply from industrial sources, best practice benchmark capture costs and the demand potential of CO 2 utilization and storage scenarios with comparative statics, conclusions can be drawn on the role of different CO 2 sources. For near-term scenarios the demand for the commodity CO 2 can be covered from industrial processes, that emit CO 2 at a high purity and low benchmark capture cost of approximately 33 €/t. In the long-term, with synthetic fuel production and large-scale CO 2 utilization, CO 2 is likely to be available from a variety of processes at benchmark costs of approx. 65 €/t. Even if fossil-fired power generation is phased out, the CO 2 emissions of current industrial processes would suffice for ambitious CCU demand scenarios. At current economic conditions, the business case for CO 2 utilization is technology specific and depends on whether efficiency gains or substitution of volatile priced raw materials can be achieved. Overall, it is argued that CCU should be advanced complementary to mitigation technologies and can unfold its potential in creating local circular economy solutions.

Increased light-use efficiency in northern terrestrial ecosystems indicated by CO 2 and greening observations: INCREASE IN NH LIGHT USE EFFICIENCY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, Rebecca T.; Prentice, Iain Colin; Graven, Heather

2016-11-04

Observations show an increasing amplitude in the seasonal cycle of CO2 (ASC) north of 45°N of 56 ± 9.8% over the last 50 years and an increase in vegetation greenness of 7.5–15% in high northern latitudes since the 1980s. However, the causes of these changes remain uncertain. Historical simulations from terrestrial biosphere models in the Multiscale Synthesis and Terrestrial Model Intercomparison Project are compared to the ASC and greenness observations, using the TM3 atmospheric transport model to translate surface fluxes into CO2 concentrations. We find that the modeled change in ASC is too small but the mean greening trend ismore » generally captured. Modeled increases in greenness are primarily driven by warming, whereas ASC changes are primarily driven by increasing CO2. We suggest that increases in ecosystem-scale light use efficiency (LUE) have contributed to the observed ASC increase but are underestimated by current models. We highlight potential mechanisms that could increase modeled LUE.« less

Solvent Effects on the Photothermal Regeneration of CO 2 in Monoethanolamine Nanofluids

DOE PAGES

Nguyen, Du; Stolaroff, Joshuah; Esser-Kahn, Aaron

2015-11-02

We present that a potential approach to reduce energy costs associated with carbon capture is to use external and renewable energy sources. The photothermal release of CO 2 from monoethanolamine mediated by nanoparticles is a unique solution to this problem. When combined with light-absorbing nanoparticles, vapor bubbles form inside the capture solution and release the CO 2 without heating the bulk solvent. The mechanism by which CO 2 is released remained unclear, and understanding this process would improve the efficiency of photothermal CO 2 release. Here we report the use of different cosolvents to improve or reduce the photothermal regenerationmore » of CO 2 captured by monoethanolamine. We found that properties that reduce the residence time of the gas bubbles (viscosity, boiling point, and convection direction) can enhance the regeneration efficiencies. The reduction of bubble residence times minimizes the reabsorption of CO 2 back into the capture solvent where bulk temperatures remain lower than the localized area surrounding the nanoparticle. These properties shed light on the mechanism of release and indicated methods for improving the efficiency of the process. We used this knowledge to develop an improved photothermal CO 2 regeneration system in a continuously flowing setup. Finally, using techniques to reduce residence time in the continuously flowing setup, such as alternative cosolvents and smaller fluid volumes, resulted in regeneration efficiency enhancements of over 200%.« less

Solvent Effects on the Photothermal Regeneration of CO 2 in Monoethanolamine Nanofluids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, Du; Stolaroff, Joshuah; Esser-Kahn, Aaron

We present that a potential approach to reduce energy costs associated with carbon capture is to use external and renewable energy sources. The photothermal release of CO 2 from monoethanolamine mediated by nanoparticles is a unique solution to this problem. When combined with light-absorbing nanoparticles, vapor bubbles form inside the capture solution and release the CO 2 without heating the bulk solvent. The mechanism by which CO 2 is released remained unclear, and understanding this process would improve the efficiency of photothermal CO 2 release. Here we report the use of different cosolvents to improve or reduce the photothermal regenerationmore » of CO 2 captured by monoethanolamine. We found that properties that reduce the residence time of the gas bubbles (viscosity, boiling point, and convection direction) can enhance the regeneration efficiencies. The reduction of bubble residence times minimizes the reabsorption of CO 2 back into the capture solvent where bulk temperatures remain lower than the localized area surrounding the nanoparticle. These properties shed light on the mechanism of release and indicated methods for improving the efficiency of the process. We used this knowledge to develop an improved photothermal CO 2 regeneration system in a continuously flowing setup. Finally, using techniques to reduce residence time in the continuously flowing setup, such as alternative cosolvents and smaller fluid volumes, resulted in regeneration efficiency enhancements of over 200%.« less

In situ characterization of cofacial Co(IV) centers in Co4O4 cubane: Modeling the high-valent active site in oxygen-evolving catalysts.

PubMed

Brodsky, Casey N; Hadt, Ryan G; Hayes, Dugan; Reinhart, Benjamin J; Li, Nancy; Chen, Lin X; Nocera, Daniel G

2017-04-11

The Co 4 O 4 cubane is a representative structural model of oxidic cobalt oxygen-evolving catalysts (Co-OECs). The Co-OECs are active when residing at two oxidation levels above an all-Co(III) resting state. This doubly oxidized Co(IV) 2 state may be captured in a Co(III) 2 (IV) 2 cubane. We demonstrate that the Co(III) 2 (IV) 2 cubane may be electrochemically generated and the electronic properties of this unique high-valent state may be probed by in situ spectroscopy. Intervalence charge-transfer (IVCT) bands in the near-IR are observed for the Co(III) 2 (IV) 2 cubane, and spectroscopic analysis together with electrochemical kinetics measurements reveal a larger reorganization energy and a smaller electron transfer rate constant for the doubly versus singly oxidized cubane. Spectroelectrochemical X-ray absorption data further reveal systematic spectral changes with successive oxidations from the cubane resting state. Electronic structure calculations correlated to experimental data suggest that this state is best represented as a localized, antiferromagnetically coupled Co(IV) 2 dimer. The exchange coupling in the cofacial Co(IV) 2 site allows for parallels to be drawn between the electronic structure of the Co 4 O 4 cubane model system and the high-valent active site of the Co-OEC, with specific emphasis on the manifestation of a doubly oxidized Co(IV) 2 center on O-O bond formation.

In situ characterization of cofacial Co(IV) centers in Co 4O 4 cubane: Modeling the high-valent active site in oxygen-evolving catalysts

DOE PAGES

Brodsky, Casey N.; Hadt, Ryan G.; Hayes, Dugan; ...

2017-03-27

The Co 4O 4 cubane is a representative structural model of oxidic cobalt oxygen evolving catalysts (Co-OECs). The Co-OECs are active when residing at two oxidation levels above an all Co(III) resting state. This doubly oxidized Co(IV) 2 state may be captured in a Co(III) 2(IV) 2 cubane. We demonstrate that the Co(III) 2(IV) 2 cubane may be electrochemically generated and the electronic properties of this unique high-valent state may be probed by in situ spectroscopy. Intervalence charge transfer (IVCT) bands in the near-IR are observed for the Co(III) 2(IV) 2 cubane, and spectroscopic analysis together with electrochemical kinetics measurementsmore » reveal a larger reorganization energy and a smaller electron transfer rate constant for the doubly versus singly oxidized cubane. Spectroelectrochemical X-ray absorption data further reveal systematic spectral changes with successive oxidations from the cubane resting state. Electronic structure calculations correlated to experimental data suggest that this state is best represented as a localized, antiferromagnetically coupled Co(IV) 2 dimer. The exchange coupling in the cofacial Co(IV) 2 site allows for parallels to be drawn between the electronic structure of the Co 4O 4 cubane model system and the high valent active site of the Co-OEC, with specific emphasis on the manifestation of a doubly oxidized Co(IV) 2 center on O–O bond formation.« less

Sensitivity of CO2 storage performance to varying rates and dynamic injectivity in the Bunter Sandstone, UK

NASA Astrophysics Data System (ADS)

Kolster, C.; Mac Dowell, N.; Krevor, S. C.; Agada, S.

2016-12-01

Carbon capture and storage (CCS) is needed for meeting legally binding greenhouse gas emissions targets in the UK (ECCC 2016). Energy systems models have been key to identifying the importance of CCS but they tend to impose few constraints on the availability and use of geologic CO2 storage reservoirs. Our aim is to develop simple models that use dynamic representations of limits on CO2 storage resources. This will allow for a first order representation of the storage reservoir for use in systems models with CCS. We use the ECLIPSE reservoir simulator and a model of the Southern North Sea Bunter Sandstone saline aquifer. We analyse reservoir performance sensitivities to scenarios of varying CO2 injection demand for a future UK low carbon energy market. With 12 injection sites, we compare the impact of injecting at a constant 2MtCO2/year per site and varying this rate by a factor of 1.8 and 0.2 cyclically every 5 and 2.5 years over 50 years of injection. The results show a maximum difference in average reservoir pressure of 3% amongst each case and a similar variation in plume migration extent. This suggests that simplified models can maintain accuracy by using average rates of injection over similar time periods. Meanwhile, by initiating injection at rates limited by pressurization at the wellhead we find that injectivity steadily increases. As a result, dynamic capacity increases. We find that instead of injecting into sites on a need basis, we can strategically inject the CO2 into 6 of the deepest sites increasing injectivity for the first 15 years by 13%. Our results show injectivity as highly dependent on reservoir heterogeneity near the injection site. Injecting 1MTCO2/year into a shallow, low permeability and porosity site instead of into a deep injection site with high permeability and porosity reduces injectivity in the first 5 years by 52%. ECCC. 2016. Future of Carbon Capture and Storage in the UK. UK Parliament House of Commons, Energy and Climate Change Committee, London: The Stationary Office Limited.

Predicting long-term performance of engineered geologic carbon dioxide storage systems to inform decisions amidst uncertainty

NASA Astrophysics Data System (ADS)

Pawar, R.

2016-12-01

Risk assessment and risk management of engineered geologic CO2 storage systems is an area of active investigation. The potential geologic CO2 storage systems currently under consideration are inherently heterogeneous and have limited to no characterization data. Effective risk management decisions to ensure safe, long-term CO2 storage requires assessing and quantifying risks while taking into account the uncertainties in a storage site's characteristics. The key decisions are typically related to definition of area of review, effective monitoring strategy and monitoring duration, potential of leakage and associated impacts, etc. A quantitative methodology for predicting a sequestration site's long-term performance is critical for making key decisions necessary for successful deployment of commercial scale geologic storage projects where projects will require quantitative assessments of potential long-term liabilities. An integrated assessment modeling (IAM) paradigm which treats a geologic CO2 storage site as a system made up of various linked subsystems can be used to predict long-term performance. The subsystems include storage reservoir, seals, potential leakage pathways (such as wellbores, natural fractures/faults) and receptors (such as shallow groundwater aquifers). CO2 movement within each of the subsystems and resulting interactions are captured through reduced order models (ROMs). The ROMs capture the complex physical/chemical interactions resulting due to CO2 movement and interactions but are computationally extremely efficient. The computational efficiency allows for performing Monte Carlo simulations necessary for quantitative probabilistic risk assessment. We have used the IAM to predict long-term performance of geologic CO2 sequestration systems and to answer questions related to probability of leakage of CO2 through wellbores, impact of CO2/brine leakage into shallow aquifer, etc. Answers to such questions are critical in making key risk management decisions. A systematic uncertainty quantification approach can been used to understand how uncertain parameters associated with different subsystems (e.g., reservoir permeability, wellbore cement permeability, wellbore density, etc.) impact the overall site performance predictions.

Early opportunities of CO2 geological storage deployment in coal chemical industry in China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei, Ning; Li, Xiaochun; Liu, Shengnan

2014-11-12

Abstract: Carbon dioxide capture and geological storage (CCS) is regarded as a promising option for climate change mitigation; however, the high capture cost is the major barrier to large-scale deployment of CCS technologies. High-purity CO2 emission sources can reduce or even avoid the capture requirements and costs. Among these high-purity CO2 sources, certain coal chemical industry processes are very important, especially in China. In this paper, the basic characteristics of coal chemical industries in China is investigated and analyzed. As of 2013 there were more than 100 coal chemical plants in operation or in late planning stages. These emission sourcesmore » together emit 430 million tons CO2 per year, of which about 30% are emit high-purity and pure CO2 (CO2 concentration >80% and >99% respectively).Four typical source-sink pairs are studied by a techno-economic evaluation, including site screening and selection, source-sink matching, concept design, and experienced economic evaluation. The technical-economic evaluation shows that the levelized cost of a CO2 capture and aquifer storage project in the coal chemistry industry ranges from 14 USD/t to 17 USD/t CO2. When a 15USD/t CO2 tax and 15USD/t for CO2 sold to EOR are considered, the levelized cost of CCS project are negative, which suggests a net economic benefit from some of these CCS projects. This might provide China early opportunities to deploy and scale-up CCS projects in the near future.« less

Nitrosamines and Nitramines in Amine-Based Carbon Dioxide Capture Systems: Fundamentals, Engineering Implications, and Knowledge Gaps.

PubMed

Yu, Kun; Mitch, William A; Dai, Ning

2017-10-17

Amine-based absorption is the primary contender for postcombustion CO 2 capture from fossil fuel-fired power plants. However, significant concerns have arisen regarding the formation and emission of toxic nitrosamine and nitramine byproducts from amine-based systems. This paper reviews the current knowledge regarding these byproducts in CO 2 capture systems. In the absorber, flue gas NO x drives nitrosamine and nitramine formation after its dissolution into the amine solvent. The reaction mechanisms are reviewed based on CO 2 capture literature as well as biological and atmospheric chemistry studies. In the desorber, nitrosamines are formed under high temperatures by amines reacting with nitrite (a hydrolysis product of NO x ), but they can also thermally decompose following pseudo-first order kinetics. The effects of amine structure, primarily amine order, on nitrosamine formation and the corresponding mechanisms are discussed. Washwater units, although intended to control emissions from the absorber, can contribute to additional nitrosamine formation when accumulated amines react with residual NO x . Nitramines are much less studied than nitrosamines in CO 2 capture systems. Mitigation strategies based on the reaction mechanisms in each unit of the CO 2 capture systems are reviewed. Lastly, we highlight research needs in clarifying reaction mechanisms, developing analytical methods for both liquid and gas phases, and integrating different units to quantitatively predict the accumulation and emission of nitrosamines and nitramines.

Doping Li and K into Na2ZrO3 Sorbent to Improve Its CO2 Capture Capability

NASA Astrophysics Data System (ADS)

Duan, Yuhua

Carbon dioxide is one of the major combustion products which once released into the air can contribute to global climate change. Solid sorbents have been reported in several previous studies to be promising candidates for CO2 sorbent applications due to their high CO2 absorption capacities at moderate working temperatures. However, at a given CO2 pressure, the turnover temperature (Tt) of an individual solid capture CO2 reaction is fixed and may be outside the operating temperature range (ΔTo) for a particularly capture technology. In order to shift such Tt for a solid into the range of ΔTo, its corresponding thermodynamic property must be changed by changing its structure by reacting (mixing) with other materials or doping with other elements. As an example, by combining thermodynamic database searching with ab initio thermodynamics calculations, in this work, we explored the Li- and K-doping effects on the Tt shifts of Na2ZrO3 at different doping levels. The obtained results showed that compared to pure Na2ZrO3, the Li- and K-doped mixtures Na2-αMαZrO3 (M =Li, K) have lower Tt and higher CO2 capture capacities.

Modeling CO2 mass transfer in amine mixtures: PZ-AMP and PZ-MDEA.

PubMed

Puxty, Graeme; Rowland, Robert

2011-03-15

The most common method of carbon dioxide (CO(2)) capture is the absorption of CO(2) into a falling thin film of an aqueous amine solution. Modeling of mass transfer during CO(2) absorption is an important way to gain insight and understanding about the underlying processes that are occurring. In this work a new software tool has been used to model CO(2) absorption into aqueous piperazine (PZ) and binary mixtures of PZ with 2-amino-2-methyl-1-propanol (AMP) or methyldiethanolamine (MDEA). The tool solves partial differential and simultaneous equations describing diffusion and chemical reaction automatically derived from reactions written using chemical notation. It has been demonstrated that by using reactions that are chemically plausible the mass transfer in binary mixtures can be fully described by combining the chemical reactions and their associated parameters determined for single amines. The observed enhanced mass transfer in binary mixtures can be explained through chemical interactions occurring in the mixture without need to resort to using additional reactions or unusual transport phenomena such as the "shuttle mechanism".

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doug Cathro

The Lake Charles CCS Project is a large-scale industrial carbon capture and sequestration (CCS) project which will demonstrate advanced technologies that capture and sequester carbon dioxide (CO{sub 2}) emissions from industrial sources into underground formations. Specifically the Lake Charles CCS Project will accelerate commercialization of large-scale CO{sub 2} storage from industrial sources by leveraging synergy between a proposed petroleum coke to chemicals plant (the LCC Gasification Project) and the largest integrated anthropogenic CO{sub 2} capture, transport, and monitored sequestration program in the U.S. Gulf Coast Region. The Lake Charles CCS Project will promote the expansion of EOR in Texas andmore » Louisiana and supply greater energy security by expanding domestic energy supplies. The capture, compression, pipeline, injection, and monitoring infrastructure will continue to sequester CO{sub 2} for many years after the completion of the term of the DOE agreement. The objectives of this project are expected to be fulfilled by working through two distinct phases. The overall objective of Phase 1 was to develop a fully definitive project basis for a competitive Renewal Application process to proceed into Phase 2 - Design, Construction and Operations. Phase 1 includes the studies attached hereto that will establish: the engineering design basis for the capture, compression and transportation of CO{sub 2} from the LCC Gasification Project, and the criteria and specifications for a monitoring, verification and accounting (MVA) plan at the Hastings oil field in Texas. The overall objective of Phase 2, provided a successful competitive down-selection, is to execute design, construction and operations of three capital projects: (1) the CO{sub 2} capture and compression equipment, (2) a Connector Pipeline from the LLC Gasification Project to the Green Pipeline owned by Denbury and an affiliate of Denbury, and (3) a comprehensive MVA system at the Hastings oil field.« less

Evaluation of 11 terrestrial carbon–nitrogen cycle models against observations from two temperate Free-Air CO2 Enrichment studies

PubMed Central

Zaehle, Sönke; Medlyn, Belinda E; De Kauwe, Martin G; Walker, Anthony P; Dietze, Michael C; Hickler, Thomas; Luo, Yiqi; Wang, Ying-Ping; El-Masri, Bassil; Thornton, Peter; Jain, Atul; Wang, Shusen; Warlind, David; Weng, Ensheng; Parton, William; Iversen, Colleen M; Gallet-Budynek, Anne; McCarthy, Heather; Finzi, Adrien; Hanson, Paul J; Prentice, I Colin; Oren, Ram; Norby, Richard J

2014-01-01

We analysed the responses of 11 ecosystem models to elevated atmospheric [CO2] (eCO2) at two temperate forest ecosystems (Duke and Oak Ridge National Laboratory (ORNL) Free-Air CO2 Enrichment (FACE) experiments) to test alternative representations of carbon (C)–nitrogen (N) cycle processes. We decomposed the model responses into component processes affecting the response to eCO2 and confronted these with observations from the FACE experiments. Most of the models reproduced the observed initial enhancement of net primary production (NPP) at both sites, but none was able to simulate both the sustained 10-yr enhancement at Duke and the declining response at ORNL: models generally showed signs of progressive N limitation as a result of lower than observed plant N uptake. Nonetheless, many models showed qualitative agreement with observed component processes. The results suggest that improved representation of above-ground–below-ground interactions and better constraints on plant stoichiometry are important for a predictive understanding of eCO2 effects. Improved accuracy of soil organic matter inventories is pivotal to reduce uncertainty in the observed C–N budgets. The two FACE experiments are insufficient to fully constrain terrestrial responses to eCO2, given the complexity of factors leading to the observed diverging trends, and the consequential inability of the models to explain these trends. Nevertheless, the ecosystem models were able to capture important features of the experiments, lending some support to their projections. PMID:24467623

Estimating geological CO2 storage security to deliver on climate mitigation.

PubMed

Alcalde, Juan; Flude, Stephanie; Wilkinson, Mark; Johnson, Gareth; Edlmann, Katriona; Bond, Clare E; Scott, Vivian; Gilfillan, Stuart M V; Ogaya, Xènia; Haszeldine, R Stuart

2018-06-12

Carbon capture and storage (CCS) can help nations meet their Paris CO 2 reduction commitments cost-effectively. However, lack of confidence in geologic CO 2 storage security remains a barrier to CCS implementation. Here we present a numerical program that calculates CO 2 storage security and leakage to the atmosphere over 10,000 years. This combines quantitative estimates of geological subsurface CO 2 retention, and of surface CO 2 leakage. We calculate that realistically well-regulated storage in regions with moderate well densities has a 50% probability that leakage remains below 0.0008% per year, with over 98% of the injected CO 2 retained in the subsurface over 10,000 years. An unrealistic scenario, where CO 2 storage is inadequately regulated, estimates that more than 78% will be retained over 10,000 years. Our modelling results suggest that geological storage of CO 2 can be a secure climate change mitigation option, but we note that long-term behaviour of CO 2 in the subsurface remains a key uncertainty.

A multicriteria decision analysis model and risk assessment framework for carbon capture and storage.

PubMed

Humphries Choptiany, John Michael; Pelot, Ronald

2014-09-01

Multicriteria decision analysis (MCDA) has been applied to various energy problems to incorporate a variety of qualitative and quantitative criteria, usually spanning environmental, social, engineering, and economic fields. MCDA and associated methods such as life-cycle assessments and cost-benefit analysis can also include risk analysis to address uncertainties in criteria estimates. One technology now being assessed to help mitigate climate change is carbon capture and storage (CCS). CCS is a new process that captures CO2 emissions from fossil-fueled power plants and injects them into geological reservoirs for storage. It presents a unique challenge to decisionmakers (DMs) due to its technical complexity, range of environmental, social, and economic impacts, variety of stakeholders, and long time spans. The authors have developed a risk assessment model using a MCDA approach for CCS decisions such as selecting between CO2 storage locations and choosing among different mitigation actions for reducing risks. The model includes uncertainty measures for several factors, utility curve representations of all variables, Monte Carlo simulation, and sensitivity analysis. This article uses a CCS scenario example to demonstrate the development and application of the model based on data derived from published articles and publicly available sources. The model allows high-level DMs to better understand project risks and the tradeoffs inherent in modern, complex energy decisions. © 2014 Society for Risk Analysis.

Supersonic Post-Combustion Inertial CO 2 Extraction System Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balepin, Vladimir

This report summarizes the effort carried out under NETL contract DE- FE0013122 from 1 October 2013 to 31 March 2017. As described in this document, technical challenges realized during the performance of this project resulted in completion of only the first two of three planned budget periods. Despite this outcome, substantial progress was made toward understanding and maturing the CO 2 capture technology under consideration and considerable future promise remains for applications requiring lower CO 2 capture and/or lower CO 2.

Preparation Methods of Metal Organic Frameworks and Their Capture of CO2

NASA Astrophysics Data System (ADS)

Zhang, Linjian; Liand, Fangqin; Luo, Liangfei

2018-01-01

The increasingly serious greenhouse effect makes people pay more attention to the capture and storage technology of CO2. Metal organic frameworks (MOFs) have the advantages of high specific surface area, porous structure and controllable structure, and become the research focus of CO2 emission reduction technology in recent years. In this paper, the characteristics, preparation methods and application of MOFs in the field of CO2 adsorption and separation are discussed, especially the application of flue gas environment in power plants.

Integrating Waste Heat from CO 2 Removal and Coal-Fired Flue Gas to Increase Plant Efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Irvin, Nick; Kowalczyk, Joseph

In project DE-FE0007525, Southern Company Services demonstrated heat integration methods for the capture and sequestration of carbon dioxide produced from pulverized coal combustion. A waste heat recovery technology (termed High Efficiency System) from Mitsubishi Heavy Industries America was integrated into an existing 25-MW amine-based CO 2 capture process (Kansai Mitsubishi Carbon Dioxide Recovery Process®1) at Southern Company’s Plant Barry to evaluate improvements in the energy performance of the pulverized coal plant and CO 2 capture process. The heat integration system consists of two primary pieces of equipment: (1) the CO 2 Cooler which uses product CO 2 gas from themore » capture process to heat boiler condensate, and (2) the Flue Gas Cooler which uses air heater outlet flue gas to further heat boiler condensate. Both pieces of equipment were included in the pilot system. The pilot CO 2 Cooler used waste heat from the 25-MW CO 2 capture plant (but not always from product CO 2 gas, as intended). The pilot Flue Gas Cooler used heat from a slipstream of flue gas taken from downstream of Plant Barry’s air heater. The pilot also included a 0.25-MW electrostatic precipitator. The 25-MW High Efficiency System operated for approximately six weeks over a four month time period in conjunction with the 25-MW CO 2 capture facility at Plant Barry. Results from the program were used to evaluate the technical and economic feasibility of full-scale implementation of this technology. The test program quantified energy efficiency improvements to a host power plant that could be realized due to the High Efficiency System. Through the execution of this project, the team verified the integrated operation of the High Efficiency System and Kansai Mitsubishi Carbon Dioxide Recovery Process®. The ancillary benefits of the High Efficiency System were also quantified, including reduced water consumption, a decrease in toxic air emissions, and better overall air quality control systems performance.« less

Primary, secondary, and tertiary amines for CO2 capture: designing for mesoporous CO2 adsorbents.

PubMed

Ko, Young Gun; Shin, Seung Su; Choi, Ung Su

2011-09-15

CO(2) emissions, from fossil-fuel-burning power plants, the breathing, etc., influence the global worming on large scale and the man's work efficiency on small scale. The reversible capture of CO(2) is a prominent feature of CO(2) organic-inorganic hybrid adsorbent to sequester CO(2). Herein, (3-aminopropyl) trimethoxysilane (APTMS), [3-(methylamino)propyl] trimethoxysilane (MAPTMS), and [3-(diethylamino) propyl] trimethoxysilane (DEAPTMS) are immobilized on highly ordered mesoporous silicas (SBA-15) to catch CO(2) as primary, secondary, and tertiary aminosilica adsorbents. X-ray photoelectron spectroscopy was used to analyze the immobilized APTMS, MAPTMS, and DEAPTMS on the SBA-15. We report an interesting discovery that the CO(2) adsorption and desorption on the adsorbent depend on the amine type of the aminosilica adsorbent. The adsorbed CO(2) was easily desorbed from the adsorbent with the low energy consumption in the order of tertiary, secondary, and primary amino-adsorbents while the adsorption amount and the bonding-affinity increased in the reverse order. The effectiveness of amino-functionalized (1(o), 2(o), and 3(o) amines) SBA-15s as a CO(2) capturing agent was investigated in terms of adsorption capacity, adsorption-desorption kinetics, and thermodynamics. This work demonstrates apt amine types to catch CO(2) and regenerate the adsorbent, which may open new avenues to designing "CO(2) basket". Copyright © 2011. Published by Elsevier Inc.

Enhanced Seasonal Exchange of CO2 by Northern Ecosystems - Observations and Models

NASA Astrophysics Data System (ADS)

Graven, H. D.; Keeling, R. F.; Piper, S. C.; Patra, P. K.; Stephens, B. B.; Wofsy, S. C.; Welp, L. R.; Sweeney, C.; Tans, P. P.; Kelley, J. J.; Daube, B. C.; Kort, E. A.; Santoni, G.; Bent, J. D.; Thomas, R.; Prentice, I. C.

2014-12-01

Long-term measurements of atmospheric CO2 have revealed increasing amplitude in seasonal variations at Northern Hemisphere sites. In a recent paper1, we extended the analysis of seasonal CO2 amplitude using aircraft data from 1958-61 and 2009-11 and found large increases of 50% in the mid-troposphere north of 45°N. Changes in amplitude south of 45°N were less than 25%. The observations indicate that seasonal CO2 exchanges with northern terrestrial ecosystems must have increased by 30-60% over the past 50 years. The increased exchange is likely widespread over northern ecosystems but it must be focused in boreal forests to match the observed spatial pattern in the aircraft data. Small decreases in seasonal CO2 exchange of subtropical and tropical regions may also contribute to CO2 amplitude changes. The required increases in seasonal CO2 exchange in northern ecosystems are larger than simulated by terrestrial models, indicating the models do not capture substantial ecological changes occurring since 1960. This presentation will give an overview of the recent paper1, highlighting the atmospheric evidence for a dominant influence from boreal forests and from the main growing season months. It will also expand on the investigation of modeled changes in seasonal CO2 flux using CMIP5 and other model intercomparisons, including the modeled influences of carbon vs climate drivers. 1. Graven et al. 2013, Enhanced Seasonal Exchange of CO2 by Northern Ecosystems Since 1960, Science, 341, 6150, 1085-1089. DOI: 10.1126/science.1239207

Compact, Lightweight Adsorber and Sabatier Reactor for CO2 Capture and Reduction for Consumable and Propellant Production

NASA Technical Reports Server (NTRS)

Junaedi, Christian; Hawley, Kyle; Walsh, Dennis; Roychoudhury, Subir; Busby, Stacy A.; Abney, Morgan B.; Perry, Jay L.; Knox, James C.

2012-01-01

The utilization of CO2 to produce (or recycle) life support consumables, such as O2 and H2O, and to generate propellant fuels is an important aspect of NASA's concept for future, long duration planetary exploration. One potential approach is to capture and use CO2 from the Martian atmosphere to generate the consumables and propellant fuels. Precision Combustion, Inc. (PCI), with support from NASA, continues to develop its regenerable adsorber technology for capturing CO2 from gaseous atmospheres (for cabin atmosphere revitalization and in-situ resource utilization applications) and its Sabatier reactor for converting CO2 to methane and water. Both technologies are based on PCI's Microlith(R) substrates and have been demonstrated to reduce size, weight, and power consumption during CO2 capture and methanation process. For adsorber applications, the Microlith substrates offer a unique resistive heating capability that shows potential for short regeneration time and reduced power requirements compared to conventional systems. For the Sabatier applications, the combination of the Microlith substrates and durable catalyst coating permits efficient CO2 methanation that favors high reactant conversion, high selectivity, and durability. Results from performance testing at various operating conditions will be presented. An effort to optimize the Sabatier reactor and to develop a bench-top Sabatier Development Unit (SDU) will be discussed.

Improved Structural Design and CO 2 Capture of Porous Hydroxy-Rich Polymeric Organic Frameworks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kidder, Michelle K.; Earl, Lyndsey D.; de Almeida, Valmor F.

2016-04-16

Polymeric organic frameworks (POFs) are tunable and robust porous materials with potential applications for gas capture, catalysis, and separations technologies. A series of new porous POFs have been synthesized from the reaction of phloroglucinol or resorcinol derivatives with aryl aldehyde precursors. The monomers have various molecular shapes including linear, bent, trigonal, and tetrahedral geometries. Depending on the size and geometric matching of the monomers, the polymers are dominantly microporous with some mesoporous character or they are non-porous. In addition to standard spectroscopic and surface characterization, the materials were screened as adsorbents for carbon dioxide capture at low pressure (0-1 bar).more » The best performing material (POF 1D) has a CO 2 capture capacity of 9.0 wt. % (2.04 mmol g -1) at 298 K and 1 bar which is comparable to other polymeric organic frameworks. Isosteric heats of adsorption for POF 1A, POF 2A, and POF 2B were found to be dependent on the weight percent of CO 2 adsorbed: this suggests there are both chemisorptive and physisorptive components of CO 2 capture by the POFs.« less

Sequestering CO2 in the Ocean: Options and Consequences

NASA Astrophysics Data System (ADS)

Rau, G. H.; Caldeira, K.

2002-12-01

The likelihood of negative climate and environmental impacts associated with increasing atmospheric CO2 has prompted serious consideration of various CO2 mitigation strategies. Among these are methods of capturing and storing of CO2 in the ocean. Two approaches that have received the most attention in this regard have been i) ocean fertilization to enhanced biological uptake and fixation of CO2, and ii) the chemical/mechanical capture and injection of CO2 into the deep ocean. Both methods seek to enhance or speed up natural mechanisms of CO2 uptake and storage by the ocean, namely i) the biological CO2 "pump" or ii) the passive diffusion of CO2 into the surface ocean and subsequent mixing into the deep sea. However, as will be reviewed, concerns about the capacity and effectiveness of either strategy in long-term CO2 sequestration have been raised. Both methods are not without potentially significant environmental impacts, and the costs of CO2 capture and injection (option ii) are currently prohibitive. An alternate method of ocean CO2 sequestration would be to react and hydrate CO2 rich waste gases (e.g., power plant flue gas) with seawater and to subsequently neutralize the resulting carbonic acid with limestone to produce calcium and bicarbonate ions in solution. This approach would simply speed up the CO2 uptake and sequestration that naturally (but very slowly) occurs via global carbonate weathering. This would avoid much of the increased acidity associated with direct CO2 injection while obviating the need for costly CO2 separation and capture. The addition of the resulting bicarbonate- and carbonate-rich solution to the ocean would help to counter the decrease in pH and carbonate ion concentration, and hence loss of biological calcification that is presently occurring as anthropogenic CO2 invades the ocean from the atmosphere. However, as with any approach to CO2 mitigation, the costs, impacts, risks, and benefits of this method need to be better understood and weighed against those of alternative strategies, including business as usual.

Separation and capture of CO2 from large stationary sources and sequestration in geological formations--coalbeds and deep saline aquifers.

PubMed

White, Curt M; Strazisar, Brian R; Granite, Evan J; Hoffman, James S; Pennline, Henry W

2003-06-01

The topic of global warming as a result of increased atmospheric CO2 concentration is arguably the most important environmental issue that the world faces today. It is a global problem that will need to be solved on a global level. The link between anthropogenic emissions of CO2 with increased atmospheric CO2 levels and, in turn, with increased global temperatures has been well established and accepted by the world. International organizations such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Intergovernmental Panel on Climate Change (IPCC) have been formed to address this issue. Three options are being explored to stabilize atmospheric levels of greenhouse gases (GHGs) and global temperatures without severely and negatively impacting standard of living: (1) increasing energy efficiency, (2) switching to less carbon-intensive sources of energy, and (3) carbon sequestration. To be successful, all three options must be used in concert. The third option is the subject of this review. Specifically, this review will cover the capture and geologic sequestration of CO2 generated from large point sources, namely fossil-fuel-fired power gasification plants. Sequestration of CO2 in geological formations is necessary to meet the President's Global Climate Change Initiative target of an 18% reduction in GHG intensity by 2012. Further, the best strategy to stabilize the atmospheric concentration of CO2 results from a multifaceted approach where sequestration of CO2 into geological formations is combined with increased efficiency in electric power generation and utilization, increased conservation, increased use of lower carbon-intensity fuels, and increased use of nuclear energy and renewables. This review covers the separation and capture of CO2 from both flue gas and fuel gas using wet scrubbing technologies, dry regenerable sorbents, membranes, cryogenics, pressure and temperature swing adsorption, and other advanced concepts. Existing commercial CO2 capture facilities at electric power-generating stations based on the use of monoethanolamine are described, as is the Rectisol process used by Dakota Gasification to separate and capture CO2 from a coal gasifier. Two technologies for storage of the captured CO2 are reviewed--sequestration in deep unmineable coalbeds with concomitant recovery of CH4 and sequestration in deep saline aquifers. Key issues for both of these techniques include estimating the potential storage capacity, the storage integrity, and the physical and chemical processes that are initiated by injecting CO2 underground. Recent studies using computer modeling as well as laboratory and field experimentation are presented here. In addition, several projects have been initiated in which CO2 is injected into a deep coal seam or saline aquifer. The current status of several such projects is discussed. Included is a commercial-scale project in which a million tons of CO2 are injected annually into an aquifer under the North Sea in Norway. The review makes the case that this can all be accomplished safely with off-the-shelf technologies. However, substantial research and development must be performed to reduce the cost, decrease the risks, and increase the safety of sequestration technologies. This review also includes discussion of possible problems related to deep injection of CO2. There are safety concerns that need to be addressed because of the possibilities of leakage to the surface and induced seismic activity. These issues are presented along with a case study of a similar incident in the past. It is clear that monitoring and verification of storage will be a crucial part of all geological sequestration practices so that such problems may be avoided. Available techniques include direct measurement of CO2 and CH4 surface soil fluxes, the use of chemical tracers, and underground 4-D seismic monitoring. Ten new hypotheses were formulated to describe what happens when CO2 is pumped into a coal seam. These hypotheses provide significant insight into the fundamental chemical, physical, and thermodynamic phenomena that occur during coal seam sequestration of CO2.

How green can black be? Assessing the potential for equipping USA's existing coal fleet with carbon capture and storage

NASA Astrophysics Data System (ADS)

Patrizio, Piera; Leduc, Sylvain; Mesfun, Sennai; Yowargana, Ping; Kraxner, Florian

2017-04-01

The mitigation of adverse environmental impacts due to climate change requires the reduction of carbon dioxide emissions - also from the U.S. energy sector, a dominant source of greenhouse-gas emissions. This is especially true for the existing fleet of coal-fired power plants, accounting for roughly two-thirds of the U.S. energy sectors' total CO2 emissions. With this aim, different carbon mitigation options have been proposed in literature, such as increasing the energy efficiency, co-firing of biomass and/or the adoption of carbon capturing technologies (BECCS). However, the extent to which these solutions can be adopted depends on a suite of site specific factors and therefore needs to be evaluated on a site-specific basis. We propose a spatially explicit approach to identify candidate coal plants for which carbon capture technologies are economically feasible, according to different economic and policy frameworks. The methodology implies the adoption of IIASA's techno economic model BeWhere, which optimizes the cost of the entire BECCS supply chain, from the biomass resources to the storage of the CO2 in the nearest geological sink. The results shows that biomass co-firing appears to be the most appealing economic solution for a larger part of the existing U.S. coal fleet, while the adoption of CCS technologies is highly dependent on the level of CO2 prices as well as on local factors such as the type of coal firing technology and proximity of storage sites.

Efficient capture of CO2 over ordered micro-mesoporous hybrid carbon nanosphere

NASA Astrophysics Data System (ADS)

Chen, Changwei; Yu, Yanke; He, Chi; Wang, Li; Huang, Huang; Albilali, Reem; Cheng, Jie; Hao, Zhengping

2018-05-01

Four kinds of carbon-based adsorbents (micro-mesoporous hybrid carbon nanosphere and N-doped hollow carbon sphere with single-, double- or ruga-shell morphology) with different structural and textural properties were prepared and systematically studied in CO2 capture. All synthesized samples possess high specific surface area (828-910 m2 g-1), large pore volume (0.71-1.81 cm3 g-1), and different micropore contents varied from 2.1% to 46.4%. Amongst, the ordered micro-mesoporous carbon nanosphere (OM-CNS) exhibits the best adsorption performance with CO2 uptake as high as 3.01 mmol g-1 under conditions of 298 K and 1.0 bar, better than most of the reported CO2 adsorbents. The excellent CO2 adsorption capacity of OM-CNS can be reasonably attributed to the synergistic effect of ordered mesopore channels and abundant structural micropores which are beneficial for the diffusion and trapping of CO2 adsorbate. Moreover, the OM-CNS shows excellent CO2 trapping selectivity and superior stability and recyclability, which endow the OM-CNS as a promising and environmental-friendly adsorbent for CO2 capture and separation under practical conditions.

Testing simulations of intra- and inter-annual variation in the plant production response to elevated CO(2) against measurements from an 11-year FACE experiment on grazed pasture.

PubMed

Li, Frank Yonghong; Newton, Paul C D; Lieffering, Mark

2014-01-01

Ecosystem models play a crucial role in understanding and evaluating the combined impacts of rising atmospheric CO2 concentration and changing climate on terrestrial ecosystems. However, we are not aware of any studies where the capacity of models to simulate intra- and inter-annual variation in responses to elevated CO2 has been tested against long-term experimental data. Here we tested how well the ecosystem model APSIM/AgPasture was able to simulate the results from a free air carbon dioxide enrichment (FACE) experiment on grazed pasture. At this FACE site, during 11 years of CO2 enrichment, a wide range in annual plant production response to CO2 (-6 to +28%) was observed. As well as running the full model, which includes three plant CO2 response functions (plant photosynthesis, nitrogen (N) demand and stomatal conductance), we also tested the influence of these three functions on model predictions. Model/data comparisons showed that: (i) overall the model over-predicted the mean annual plant production response to CO2 (18.5% cf 13.1%) largely because years with small or negative responses to CO2 were not well simulated; (ii) in general seasonal and inter-annual variation in plant production responses to elevated CO2 were well represented by the model; (iii) the observed CO2 enhancement in overall mean legume content was well simulated but year-to-year variation in legume content was poorly captured by the model; (iv) the best fit of the model to the data required all three CO2 response functions to be invoked; (v) using actual legume content and reduced N fixation rate under elevated CO2 in the model provided the best fit to the experimental data. We conclude that in temperate grasslands the N dynamics (particularly the legume content and N fixation activity) play a critical role in pasture production responses to elevated CO2 , and are processes for model improvement. © 2013 John Wiley & Sons Ltd.

Molecular modeling of field-driven ion emission from ionic liquids

NASA Astrophysics Data System (ADS)

Zhang, Fei; He, Yadong; Qiao, Rui

2017-11-01

Traditionally, operating electrosprays in the purely ionic mode is challenging, but recent experiments confirmed that such operation can be achieved using room-temperature ionic liquids as working electrolytes. Such electrosprays have shown promise in applications including chemical analysis, nanomanufacturing, and space propulsion. The mechanistic and quantitative understanding of such electrosprays at the molecular level, however, remain limited at present. In this work, we simulated ion emission from EMIM-PF6 ionic liquid films using the molecular dynamics method. We show that, when the surface electric field is smaller than 1.5V/nm, the ion emission current predicted using coarse-grained ionic liquid model observes the classical scaling law by J. V. Iribarne and B. A. Thomson, i.e., ln(Je/ σ) En1/2. These simulations, however, cannot capture the co-emission of cations and anions from ionic liquid surface observed in some experiments. Such co-emission was successfully captured when united-atom models were adopted for the ionic liquids. By examining the co-emission events with picosecond, sub-angstrom resolution, we clarified the origins of the co-emission phenomenon and delineate the molecular events leading to ion emission.

Developing Battery Computer Aided Engineering Tools for Military Vehicles

DTIC Science & Technology

2013-12-01

Task 1.b Modeling Bullet penetration. The purpose of Task 1.a was to extend the chemical kinetics models of CoO2 cathodes developed under CAEBAT to...lithium- ion batteries. The new finite element model captures swelling/shrinking in cathodes /anodes due to thermal expansion and lithium intercalation...Solid Electrolyte Interphase (SEI) layer decomposition 80 2 Anode — electrolyte 100 3 Cathode — electrolyte 130 4 Electrolyte decomposition 180

Atmospheric CO2 capture for the artificial photosynthetic system.

PubMed

Nogalska, Adrianna; Zukowska, Adrianna; Garcia-Valls, Ricard

2018-04-15

The aim of these studies is to evaluate the ambient CO 2 capture abilities of the membrane contactor system in the same conditions as leafs, such as ambient temperature, pressure and low CO 2 concentration, where the only driving force is the concentration gradient. The polysulfone membrane employed was made by a phase inversion process and characterized by ESEM micrographs which were used to determine the thickness, asymmetry and pore size. Besides, the porosity of the membrane was measured from the membrane and polysulfone density correlation and the hydrophobicity was analyzed by contact angle measurements. Moreover, the compatibility of membrane and absorbent was evaluated, in order to exclude wetting issues by meaning of swelling, dynamic contact angle and AFM analysis. The prepared membranes were introduced into a cross flow module and used as contactors between CO 2 and the absorbing media, a potassium hydroxide solution. The influence of the membrane thickness, absorbent stirring rate, solution pH and absorption time on CO 2 capture were evaluated. Absorbent solution stirring rate showed no statistically significant influence on absorption. We observed a non-linear correlation between the capture rate and the increase of absorbent solution pH as well as absorption time. The results showed that the efficiency of our CO 2 capture system is similar to stomatal carbon dioxide assimilation rate, achieving stable value of 20μmol/m 2 ·s after 1h of experiment. Copyright © 2017 Elsevier B.V. All rights reserved.

CaO-based CO2 sorbents: from fundamentals to the development of new, highly effective materials.

PubMed

Kierzkowska, Agnieszka M; Pacciani, Roberta; Müller, Christoph R

2013-07-01

The enormous anthropogenic emission of the greenhouse gas CO2 is most likely the main reason for climate change. Considering the continuing and indeed growing utilisation of fossil fuels for electricity generation and transportation purposes, development and implementation of processes that avoid the associated emissions of CO2 are urgently needed. CO2 capture and storage, commonly termed CCS, would be a possible mid-term solution to reduce the emissions of CO2 into the atmosphere. However, the costs associated with the currently available CO2 capture technology, that is, amine scrubbing, are prohibitively high, thus making the development of new CO2 sorbents a highly important research challenge. Indeed, CaO, readily obtained through the calcination of naturally occurring limestone, has been proposed as an alternative CO2 sorbent that could substantially reduce the costs of CO2 capture. However, one of the major drawbacks of using CaO derived from natural sources is its rapidly decreasing CO2 uptake capacity with repeated carbonation-calcination reactions. Here, we review the current understanding of fundamental aspects of the cyclic carbonation-calcination reactions of CaO such as its reversibility and kinetics. Subsequently, recent attempts to develop synthetic, CaO-based sorbents that possess high and cyclically stable CO2 uptakes are presented. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mesoporous fluorocarbon-modified silica aerogel membranes enabling long-term continuous CO2 capture with large absorption flux enhancements.

PubMed

Lin, Yi-Feng; Chen, Chien-Hua; Tung, Kuo-Lun; Wei, Te-Yu; Lu, Shih-Yuan; Chang, Kai-Shiun

2013-03-01

The use of a membrane contactor combined with a hydrophobic porous membrane and an amine absorbent has attracted considerable attention for the capture of CO2 because of its extensive use, low operational costs, and low energy consumption. The hydrophobic porous membrane interface prevents the passage of the amine absorbent but allows the penetration of CO2 molecules that are captured by the amine absorbent. Herein, highly porous SiO2 aerogels modified with hydrophobic fluorocarbon functional groups (CF3 ) were successfully coated onto a macroporous Al2 O3 membrane; their performance in a membrane contactor for CO2 absorption is discussed. The SiO2 aerogel membrane modified with CF3 functional groups exhibits the highest CO2 absorption flux and can be continuously operated for CO2 absorption for extended periods of time. This study suggests that a SiO2 aerogel membrane modified with CF3 functional groups could potentially be used in a membrane contactor for CO2 absorption. Also, the resulting hydrophobic SiO2 aerogel membrane contactor is a promising technology for large-scale CO2 absorption during the post-combustion process in power plants. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Comparative Data-Based Modeling Study on Respiratory CO2 Gas Exchange during Mechanical Ventilation

PubMed Central

Kim, Chang-Sei; Ansermino, J. Mark; Hahn, Jin-Oh

2016-01-01

The goal of this study is to derive a minimally complex but credible model of respiratory CO2 gas exchange that may be used in systematic design and pilot testing of closed-loop end-tidal CO2 controllers in mechanical ventilation. We first derived a candidate model that captures the essential mechanisms involved in the respiratory CO2 gas exchange process. Then, we simplified the candidate model to derive two lower-order candidate models. We compared these candidate models for predictive capability and reliability using experimental data collected from 25 pediatric subjects undergoing dynamically varying mechanical ventilation during surgical procedures. A two-compartment model equipped with transport delay to account for CO2 delivery between the lungs and the tissues showed modest but statistically significant improvement in predictive capability over the same model without transport delay. Aggregating the lungs and the tissues into a single compartment further degraded the predictive fidelity of the model. In addition, the model equipped with transport delay demonstrated superior reliability to the one without transport delay. Further, the respiratory parameters derived from the model equipped with transport delay, but not the one without transport delay, were physiologically plausible. The results suggest that gas transport between the lungs and the tissues must be taken into account to accurately reproduce the respiratory CO2 gas exchange process under conditions of wide-ranging and dynamically varying mechanical ventilation conditions. PMID:26870728

An adsorption of carbon dioxide on activated carbon controlled by temperature swing adsorption

NASA Astrophysics Data System (ADS)

Tomas, Korinek; Karel, Frana

2017-09-01

This work deals with a method of capturing carbon dioxide (CO2) in indoor air. Temperature Swing Adsorption (TSA) on solid adsorbent was chosen for CO2 capture. Commercial activated carbon (AC) in form of extruded pellets was used as a solid adsorbent. There was constructed a simple device to testing effectiveness of CO2 capture in a fixed bed with AC. The TSA cycle was also simulated using the open-source software OpenFOAM. There was a good agreement between results obtained from numerical simulations and experimental data for adsorption process.

ECONOMIC EVALUATION OF CO2 STORAGE AND SINK ENHANCEMENT OPTIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bert Bock; Richard Rhudy; Howard Herzog

2003-02-01

This project developed life-cycle costs for the major technologies and practices under development for CO{sub 2} storage and sink enhancement. The technologies evaluated included options for storing captured CO{sub 2} in active oil reservoirs, depleted oil and gas reservoirs, deep aquifers, coal beds, and oceans, as well as the enhancement of carbon sequestration in forests and croplands. The capture costs for a nominal 500 MW{sub e} integrated gasification combined cycle plant from an earlier study were combined with the storage costs from this study to allow comparison among capture and storage approaches as well as sink enhancements.

Reconciling top-down and bottom-up estimates of CO2 fluxes to understand increased seasonal exchange in Northern ecosystems

NASA Astrophysics Data System (ADS)

Bastos, A.; Ciais, P.; Zhu, D.; Maignan, F.; Wang, X.; Chevallier, F.; Ballantyne, A.

2017-12-01

Continuous atmospheric CO2 monitoring data indicate enhanced seasonal exchange in the high-latitudes in the Northern Hemisphere (above 40oN), mainly attributed to terrestrial ecosystems. Whether this enhancement is mostly explained by increased vegetation growth due to CO2 fertilization and warming, or by changes in land-use and land-management practices is still an unsettled question (e.g. Forkel et al. (2016) and Zeng et al. (2013)). Previous studies have shown that models present variable performance in capturing trends in CO2 amplitude at CO2 monitoring sites, and that Earth System Models present large spread in their estimates of such trends. Here we integrate data of atmospheric CO2 exchange in terrestrial ecosystems by a set of atmospheric CO2 inversions and a range of land-surface models to evaluate the ability of models to reproduce changes in CO2 seasonal exchange within the observation uncertainty. We then analyze the factors that explain the model spread to understand if the trend in seasonal CO2 amplitude may indeed be a useful metric to constrain future changes in terrestrial photosynthesis (Wenzel et al., 2016). We then compare model simulations with satellite and other observation-based datasets of vegetation productivity, biomass stocks and land-cover change to test the contribution of natural (CO2 fertilization, climate) and human (land-use change) factors to the increasing trend in seasonal CO2 amplitude. Forkel, Matthias, et al. "Enhanced seasonal CO2 exchange caused by amplified plant productivity in northern ecosystems." Science 351.6274 (2016): 696-699. Wenzel, Sabrina, et al. "Projected land photosynthesis constrained by changes in the seasonal cycle of atmospheric CO2." Nature 538, no. 7626 (2016): 499-501.Zeng, Ning, et al. "Agricultural Green Revolution as a driver of increasing atmospheric CO2 seasonal amplitude." Nature 515.7527 (2014): 394.

Active CO2 Reservoir Management for Carbon Capture, Utilization, and Sequestration: Impact on Permitting, Monitoring, and Public Acceptance

NASA Astrophysics Data System (ADS)

Buscheck, T. A.; Chen, M.; Sun, Y.; Hao, Y.; Court, B.; Celia, M. A.; Wolery, T.; Aines, R. D.

2011-12-01

CO2 capture and sequestration (CCS) integrated with geothermal energy production in deep geological formations can play an important role in reducing CO2 emissions to the atmosphere and thereby mitigate global climate change. For industrial-scale CO2 injection in saline formations, pressure buildup can limit storage capacity and security. Active CO2 Reservoir Management (ACRM) combines brine production with CO2 injection to relieve pressure buildup, increase injectivity, manipulate CO2 migration, constrain brine leakage, and enable beneficial utilization of produced brine. Therefore, ACRM can be an enabler of carbon capture, utilization, and sequestration (CCUS). Useful products may include freshwater, cooling water, make-up water for pressure support in oil, gas, and geothermal reservoir operations, and geothermal energy production. Implementation barriers to industrial-scale CCS include concerns about (1) CO2 sequestration security and assurance, (2) pore-space competition with neighboring subsurface activities, (3) CO2 capture costs, and (4) water-use demands imposed by CCS operations, which is particularly important where water resources are already scarce. CCUS, enabled by ACRM, has the potential of addressing these barriers. Pressure relief from brine production can substantially reduce the driving force for potential CO2 and brine migration, as well as minimize interference with neighboring subsurface activities. Electricity generated from geothermal energy can offset a portion of the parasitic energy and financial costs of CCS. Produced brine can be used to generate freshwater by desalination technologies, such as RO, provide a source for saltwater cooling systems or be used as make-up water for oil, gas, or geothermal reservoir operations, reducing the consumption of valuable freshwater resources. We examine the impact of brine production on reducing CO2 and brine leakage. A volumetric balance between injected and produced fluids minimizes the spatial extent of the pressure perturbation, substantially reducing both the Area of Review (AoR) and interactions with neighboring subsurface activities. This will reduce pore-space competition between neighboring subsurface activities, allowing for independent planning, assessment, and permitting. Because post-injection pressure buildup is virtually eliminated, this could have a major impact on post-injection monitoring requirements. Reducing the volume of rock over which brine can migrate may significantly affect site characterization requirements, as well as the impact of parametric and conceptual model uncertainties, such as those related to abandoned wells. ACRM-CCUS has the potential of playing a beneficial role in site-characterization, permitting, and monitoring activities, and in gaining public acceptance. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Anion-activated, thermoreversible gelation system for the capture, release, and visual monitoring of CO2

NASA Astrophysics Data System (ADS)

Zhang, Xin; Lee, Songyi; Liu, Yifan; Lee, Minji; Yin, Jun; Sessler, Jonathan L.; Yoon, Juyoung

2014-04-01

Carbon dioxide (CO2) is an important green house gas. This is providing an incentive to develop new strategies to detect and capture CO2. Achieving both functions within a single molecular system represents an unmet challenge in terms of molecular design and could translate into enhanced ease of use. Here, we report an anion-activated chemosensor system, NAP-chol 1, that permits dissolved CO2 to be detected in organic media via simple color changes or through ratiometric differences in fluorescence intensity. NAP-chol 1 also acts as a super gelator for DMSO. The resulting gel is transformed into a homogeneous solution upon exposure to fluoride anions. Bubbling with CO2 regenerates the gel. Subsequent flushing with N2 or heating serves to release the CO2 and reform the sol form. This series of transformations is reversible and can be followed by easy-to-discern color changes. Thus, NAP-chol 1 allows for the capture and release of CO2 gas while acting as a three mode sensing system. In particular, it permits CO2 to be detected through reversible sol-gel transitions, simple changes in color, or ratiometric monitoring of the differences in the fluorescence features.

Intercalation and retention of carbon dioxide in a smectite clay promoted by interlayer cations.

PubMed

Michels, L; Fossum, J O; Rozynek, Z; Hemmen, H; Rustenberg, K; Sobas, P A; Kalantzopoulos, G N; Knudsen, K D; Janek, M; Plivelic, T S; da Silva, G J

2015-03-05

A good material for CO2 capture should possess some specific properties: (i) a large effective surface area with good adsorption capacity, (ii) selectivity for CO2, (iii) regeneration capacity with minimum energy input, allowing reutilization of the material for CO2 adsorption, and (iv) low cost and high environmental friendliness. Smectite clays are layered nanoporous materials that may be good candidates in this context. Here we report experiments which show that gaseous CO2 intercalates into the interlayer nano-space of smectite clay (synthetic fluorohectorite) at conditions close to ambient. The rate of intercalation, as well as the retention ability of CO2 was found to be strongly dependent on the type of the interlayer cation, which in the present case is Li(+), Na(+) or Ni(2+). Interestingly, we observe that the smectite Li-fluorohectorite is able to retain CO2 up to a temperature of 35°C at ambient pressure, and that the captured CO2 can be released by heating above this temperature. Our estimates indicate that smectite clays, even with the standard cations analyzed here, can capture an amount of CO2 comparable to other materials studied in this context.

Intercalation and Retention of Carbon Dioxide in a Smectite Clay promoted by Interlayer Cations

PubMed Central

Michels, L.; Fossum, J. O.; Rozynek, Z.; Hemmen, H.; Rustenberg, K.; Sobas, P. A.; Kalantzopoulos, G. N.; Knudsen, K. D.; Janek, M.; Plivelic, T. S.; da Silva, G. J.

2015-01-01

A good material for CO2 capture should possess some specific properties: (i) a large effective surface area with good adsorption capacity, (ii) selectivity for CO2, (iii) regeneration capacity with minimum energy input, allowing reutilization of the material for CO2 adsorption, and (iv) low cost and high environmental friendliness. Smectite clays are layered nanoporous materials that may be good candidates in this context. Here we report experiments which show that gaseous CO2 intercalates into the interlayer nano-space of smectite clay (synthetic fluorohectorite) at conditions close to ambient. The rate of intercalation, as well as the retention ability of CO2 was found to be strongly dependent on the type of the interlayer cation, which in the present case is Li+, Na+ or Ni2+. Interestingly, we observe that the smectite Li-fluorohectorite is able to retain CO2 up to a temperature of 35°C at ambient pressure, and that the captured CO2 can be released by heating above this temperature. Our estimates indicate that smectite clays, even with the standard cations analyzed here, can capture an amount of CO2 comparable to other materials studied in this context. PMID:25739522

Advanced wastewater treatment using microalgae: effect of temperature on removal of nutrients and organic carbon

NASA Astrophysics Data System (ADS)

Mohamad, Shurair; Fares, Almomani; Judd, Simon; Bhosale, Rahul; Kumar, Anand; Gosh, Ujjal; Khreisheh, Majeda

2017-05-01

This study evaluated the use of mixed indigenous microalgae (MIMA) as a treatment process for wastewaters and CO2 capturing technology at different temperatures. The study follows the growth rate of MIMA, CO2 Capturing from flue gas, removals of organic matter and nutrients from three types of wastewater (primary effluent, secondary effluent and septic effluent). A noticeable difference between the growth patterns of MIMA was observed at different CO2 and different operational temperatures. MIMA showed the highest growth grate when injected with CO2 dosage of 10% compared to the growth for the systems injected with 5% and 15 % of CO2. Ammonia and phosphorus removals for Spirulina were 69%, 75%, and 83%, and 20%, 45% and 75 % for the media injected with 0, 5 and 10% CO2. The results of this study show that simple and cost-effective microalgae-based wastewater treatment systems can be successfully employed at different temperatures as a successful CO2 capturing technology even with the small probability of inhibition at high temperatures.

Efficacy of Mosquito Traps for Collecting Potential West Nile Mosquito Vectors in a Natural Mediterranean Wetland

PubMed Central

Roiz, David; Roussel, Marion; Muñoz, Joaquin; Ruiz, Santiago; Soriguer, Ramón; Figuerola, Jordi

2012-01-01

Surveillance, research, and control of mosquito-borne diseases such as West Nile virus require efficient methods for sampling mosquitoes. We compared the efficacy of BG-Sentinel and Centers for Disease Control and Prevention (CDC)-CO2 traps in terms of the abundances of host-seeking and blood-fed female mosquitoes and the origin of mosquito bloodmeals. Our results indicate that BG-Sentinel traps that use CO2 and attractants are as effective as CDC-CO2 traps for Culex mosquito species, Ochlerotatus caspius, and they are also highly efficient at capturing Anopheles atroparvus host-seeking and blood-fed females with or without CO2. The CDC-CO2 trap is the least efficient method for capturing blood-fed females. BG-Sentinel traps with attractants and CO2 were significantly better at capturing mosquitoes that had fed on mammals than the unbaited BG-Sentinel and CDC-CO2 traps in the cases of An. atroparvus and Cx. theileri. These results may help researchers to optimize trapping methods by obtaining greater sample sizes and saving time and money. PMID:22492149

Easily regenerable solid adsorbents based on polyamines for carbon dioxide capture from the air.

PubMed

Goeppert, Alain; Zhang, Hang; Czaun, Miklos; May, Robert B; Prakash, G K Surya; Olah, George A; Narayanan, S R

2014-05-01

Adsorbents prepared easily by impregnation of fumed silica with polyethylenimine (PEI) are promising candidates for the capture of CO2 directly from the air. These inexpensive adsorbents have high CO2 adsorption capacity at ambient temperature and can be regenerated in repeated cycles under mild conditions. Despite the very low CO2 concentration, they are able to scrub efficiently all CO2 out of the air in the initial hours of the experiments. The influence of parameters such as PEI loading, adsorption and desorption temperature, particle size, and PEI molecular weight on the adsorption behavior were investigated. The mild regeneration temperatures required could allow the use of waste heat available in many industrial processes as well as solar heat. CO2 adsorption from the air has a number of applications. Removal of CO2 from a closed environment, such as a submarine or space vehicles, is essential for life support. The supply of CO2-free air is also critical for alkaline fuel cells and batteries. Direct air capture of CO2 could also help mitigate the rising concerns about atmospheric CO2 concentration and associated climatic changes, while, at the same time, provide the first step for an anthropogenic carbon cycle. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Kinetic characteristics and modeling of microalgae Chlorella vulgaris growth and CO2 biofixation considering the coupled effects of light intensity and dissolved inorganic carbon.

PubMed

Chang, Hai-Xing; Huang, Yun; Fu, Qian; Liao, Qiang; Zhu, Xun

2016-04-01

Understanding and optimizing the microalgae growth process is an essential prerequisite for effective CO2 capture using microalgae in photobioreactors. In this study, the kinetic characteristics of microalgae Chlorella vulgaris growth in response to light intensity and dissolved inorganic carbon (DIC) concentration were investigated. The greatest values of maximum biomass concentration (Xmax) and maximum specific growth rate (μmax) were obtained as 2.303 g L(-1) and 0.078 h(-1), respectively, at a light intensity of 120 μmol m(-2) s(-1) and DIC concentration of 17 mM. Based on the results, mathematical models describing the coupled effects of light intensity and DIC concentration on microalgae growth and CO2 biofixation are proposed. The models are able to predict the temporal evolution of C. vulgaris growth and CO2 biofixation rates from lag to stationary phases. Verification experiments confirmed that the model predictions agreed well with the experimental results. Copyright © 2016 Elsevier Ltd. All rights reserved.

Process for CO.sub.2 capture using zeolites from high pressure and moderate temperature gas streams

DOEpatents

Siriwardane, Ranjani V [Morgantown, WV; Stevens, Robert W [Morgantown, WV

2012-03-06

A method for separating CO.sub.2 from a gas stream comprised of CO.sub.2 and other gaseous constituents using a zeolite sorbent in a swing-adsorption process, producing a high temperature CO.sub.2 stream at a higher CO.sub.2 pressure than the input gas stream. The method utilizes CO.sub.2 desorption in a CO.sub.2 atmosphere and effectively integrates heat transfers for optimizes overall efficiency. H.sub.2O adsorption does not preclude effective operation of the sorbent. The cycle may be incorporated in an IGCC for efficient pre-combustion CO.sub.2 capture. A particular application operates on shifted syngas at a temperature exceeding 200.degree. C. and produces a dry CO.sub.2 stream at low temperature and high CO.sub.2 pressure, greatly reducing any compression energy requirements which may be subsequently required.

CO2 capture by ionic liquids - an answer to anthropogenic CO2 emissions?

PubMed

Sanglard, Pauline; Vorlet, Olivier; Marti, Roger; Naef, Olivier; Vanoli, Ennio

2013-01-01

Ionic liquids (ILs) are efficient solvents for the selective removal of CO2 from flue gas. Conventional, offthe-shelf ILs are limited in use to physisorption, which restricts their absorption capacity. After adding a chemical functionality like amines or alcohols, absorption of CO2 occurs mainly by chemisorption. This greatly enhances CO2 absorption and makes ILs suitable for potential industrial applications. By carefully choosing the anion and the cation of the IL, equimolar absorption of CO2 is possible. This paper reviews the current state of the art of CO2 capture by ILs and presents the current research in this field performed at the ChemTech Institute of the Ecole d'Ingénieurs et d'Architectes de Fribourg.

Ambient Carbon Dioxide Capture Using Boron-Rich Porous Boron Nitride: A Theoretical Study.

PubMed

Li, Lanlan; Liu, Yan; Yang, Xiaojing; Yu, Xiaofei; Fang, Yi; Li, Qiaoling; Jin, Peng; Tang, Chengchun

2017-05-10

The development of highly efficient sorbent materials for CO 2 capture under ambient conditions is of great importance for reducing the impact of CO 2 on the environment and climate change. In this account, strong CO 2 adsorption on a boron antisite (B N ) in boron-rich porous boron nitrides (p-BN) was developed and studied. The results indicated that the material achieved larger adsorption energies of 2.09 eV (201.66 kJ/mol, PBE-D). The electronic structure calculations suggested that the introduction of B N in p-BN induced defect electronic states in the energy gap region, which strongly impacted the adsorption properties of the material. The bonding between the B N defect and the CO 2 molecule was clarified, and it was found that the electron donation first occurred from CO 2 to the B N double-acceptor state then, followed by electron back-donation from B N to CO 2 accompanied by the formation of a B N -C bond. The thermodynamic properties indicated that the adsorption of CO 2 on the B N defect to form anionic CO 2 δ- species was spontaneous at temperatures below 350 K. Both the large adsorption energies and the thermodynamic properties ensured that p-BN with a B N defect could effectively capture CO 2 under ambient conditions. Finally, to evaluate the energetic stability, the defect formation energies were estimated. The formation energy of the B N defects was found to strongly depend on the chemical environment, and the selection of different reactants (B or N sources) would achieve the goal of reducing the formation energy. These findings provided a useful guidance for the design and fabrication of a porous BN sorbent for CO 2 capture.

Integrated Solvent Design for CO 2 Capture and Viscosity Tuning

DOE PAGES

Cantu, David C.; Malhotra, Deepika; Koech, Phillip K.; ...

2017-08-18

We present novel design strategies for reduced viscosity single-component, water-lean CO 2 capture organic solvent systems. Through molecular simulation, we identify the main molecular-level descriptor that influences bulk solvent viscosity. Upon loading, a zwitterionic structure forms with a small activation energy of ca 16 kJ/mol and a small stabilization of ca 6 kJ/mol. Viscosity increases exponentially with CO 2 loading due to hydrogen-bonding between neighboring Zwitterions. We find that molecular structures that promote internal hydrogen bonding (within the same molecule) and suppress interactions with neighboring molecules have low viscosities. In addition, tuning the acid/base properties leads to a shift ofmore » the equilibrium toward a non-charged (acid) form that further reduces the viscosity. Here, based on the above structural criteria, a reduced order model is also presented that allows for the quick screening of large compound libraries and down selection of promising candidates for synthesis and testing.« less

Atmospheric measurement of point source fossil fuel CO2 emissions

NASA Astrophysics Data System (ADS)

Turnbull, J. C.; Keller, E. D.; Baisden, W. T.; Brailsford, G.; Bromley, T.; Norris, M.; Zondervan, A.

2013-11-01

We use the Kapuni Gas Treatment Plant to examine methodologies for atmospheric monitoring of point source fossil fuel CO2 (CO2ff) emissions. The Kapuni plant, located in rural New Zealand, removes CO2 from locally extracted natural gas and vents that CO2 to the atmosphere, at a rate of ~0.1 Tg carbon per year. The plant is located in a rural dairy farming area, with no other significant CO2ff sources nearby, but large, diurnally varying, biospheric CO2 fluxes from the surrounding highly productive agricultural grassland. We made flask measurements of CO2 and 14CO2 (from which we derive the CO2ff component) and in situ measurements of CO2 downwind of the Kapuni plant, using a Helikite to sample transects across the emission plume from the surface up to 100 m a.g.l. We also determined the surface CO2ff content averaged over several weeks from the 14CO2 content of grass samples collected from the surrounding area. We use the WindTrax plume dispersion model to compare the atmospheric observations with the emissions reported by the Kapuni plant, and to determine how well atmospheric measurements can constrain the emissions. The model has difficulty accurately capturing the fluctuations and short-term variability in the Helikite samples, but does quite well in representing the observed CO2ff in 15 min averaged surface flask samples and in ~1 week integrated CO2ff averages from grass samples. In this pilot study, we found that using grass samples, the modeled and observed CO2ff emissions averaged over one week agreed to within 30%. The results imply that greater verification accuracy may be achieved by including more detailed meteorological observations and refining 14CO2 sampling strategies.

Pilot plant test of the advanced flash stripper for CO2 capture.

PubMed

Lin, Yu-Jeng; Chen, Eric; Rochelle, Gary T

2016-10-20

Alternative stripping processes have been proposed to reduce energy use for CO 2 capture, but only a few have been applied to pilot-scale experiments. This paper presents the first pilot plant test results of one of the most promising stripper configurations, the advanced flash stripper with cold and warm rich solvent bypass. The campaign using aqueous piperazine was carried out at UT Austin in 2015. The advanced flash stripper improves the heat duty by over 25% compared to previous campaigns using the two-stage flash, achieving 2.1 GJ per tonne CO 2 of heat duty and 32 kJ mol -1 CO 2 of total equivalent work. The bypass control strategy proposed minimized the heat duty. The test successfully demonstrated the remarkable energy performance and the operability of this advanced system. An Aspen Plus® model was validated using the pilot plant data and used to explore optimum operating and design conditions. The irreversibility analysis showed that the pilot plant performance has attained 50% thermodynamic efficiency and further energy improvement should focus on the absorber and the cross exchanger by increasing absorption rate and solvent capacity.

Pilot-Scale Silicone Process for Low-Cost Carbon Dioxide Capture. Final Scientific/Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hancu, Dan; Wood, Benjamin; Genovese, Sarah

GE Global Research has developed, over the last 8 years, a platform of cost effective CO 2 capture technologies based on a non-aqueous aminosilicone solvent (GAP-1m). As demonstrated in a previous funded DOE project (DE-FE0007502), the GAP-1m solvent has increased CO 2 working capacity, lower volatility and corrosivity than the benchmark aqueous amine technology. The current report describes the cooperative program between GE Global Research (GE GRC), and the National Carbon Capture Center (NCCC) to design, construct, and operate a pilot-scale process using GAP-1m solvent to demonstrate its performance at 0.5 MWe. (i) Performance of the GAP-1m solvent was demonstratedmore » in a 0.5 MWe pilot with real flue gas for over 900 hrs. of operation using two alternative desorption designs: a Continuous Stirred Tank Reactor (CSTR), and a Steam Stripper Column (SSC). The CSTR is a one-stage separation unit with reduced space requirements, and capital cost. The alternative is a multi-stage separation column, with improved desorption efficiency. Testing the two desorber options allowed us to identify the most cost effective, and space efficient desorber solution. (ii) CSTR Campaign: The CSTR desorber unit was designed, fabricated and integrated with the pilot solvent test unit (PSTU), replacing the PSTU Steam Stripper Column at NCCC. Solvent management and waste water special procedures were implemented to accommodate operation of the non-aqueous solvent in the PSTU. Performance of the GAP-1m solvent with the CSTR was demonstrated for over 500 hrs. while varying temperature of the desorption (230 – 265 oF), solvent circulation rate (GAP-1m : CO 2 (molar) = 1.5 – 4), and flue gas flow rates (0.2 – 0.5 MWe). Solvent carry-over in the CO 2 product was minimized by maintaining water content below 5 wt.%, and desorption pressure at 7 psig. CO 2 capture efficiency achieved was 95% at 0.25 MWe (GAP-1m : CO 2 = 4 (molar), 230 oF desorption), and 65% at 0.5 MWe (GAP-1m : CO 2 (molar) = 1.5, 248 oF). Solvent loss was dominated by thermal degradation of the rich solvent. (iii) Steam Stripper Column Campaign: Higher expected cost of the solvent vs. aqueous amines makes solvent management a top priority to maintain the low cost for the process. During the testing of the GAP-1m solvent with the CSTR, thermal degradation of the rich solvent was found to be the main mechanism in solvent loss. Small amounts of water in the working solution were found to be an effective way to enable steam stripping, thereby lowering desorption temperature, and hence reducing thermal degradation. Steam stripping also increased working capacity by 30% due to a more efficient desorption. The concept was first tested in a glass stripping column (lab scale, GE GRC), optimized in a continuous bench scale system (2 kWe, GE GRC), and demonstrated in a 0.5 MWe PSTU at NCCC. No special system modifications were required to the PSTU to accommodate the testing of the non-aqueous GAP-1 solvent with the regenerator column. SSC was found to be more robust towards solvent entrainment (H 2O < 35 wt.%). 90 – 95% CO 2 capture efficiency was achieved under stoichiometric conditions at 0.5 MWe (235 oF desorption, 2 psig and 19 wt. % H 2O). Both CO 2 capture efficiency and specific duty reached optimum conditions at 18 wt.% H 2O. Low amine degradation (< 0.05 wt.%/day) was recorded over 350 hrs. of operation. Controlled water addition to GAP-1m solvent decreased the desorption temperature, thermal degradation, and improved the CO 2 working capacity due to more efficient absorption and desorption processes. Under these conditions, the GAP-1m solvent exhibited a 25% increased working capacity, and 10% reduction in specific steam duty vs. MEA, at 10 oF lower desorption temperature. (iv) Techno-economic Analysis: The pilot-scale PSTU engineering data were used to update the capture system process models, and the techno-economic analysis was performed for a 550 MW coal fired power plant. The 1st year CO 2 removal cost for the aminosilicone-based carbon-capture process was evaluated at $48/ton CO 2 using the steam stripper column. This is a 20% reduction compared to MEA, primarily due to lower overall capital cost. CO 2 cost using the CSTR desorber is dominated by the economics of the solvent make-up. The steam stripper desorber is the preferred unit operation due to a more efficient desorption, and reduced solvent make-up rate. Further reduction in CO 2 capture cost is expected by lowering the manufacturing cost of the solvent, implementing flowsheet optimization and/or implementing the next generation aminosilicone solvent with improved stability and increased CO 2 working capacity.« less

Stochastic Modeling of CO2 Migrations and Chemical Reactions in Deep Saline Formations

NASA Astrophysics Data System (ADS)

Ni, C.; Lee, I.; Lin, C.

2013-12-01

Carbon capture and storage (CCS) has been recognized the feasible technology that can significant reduce the anthropogenic CO2 emissions from large point sources. The CO2 injection in geological formations is one of the options to permanently store the captured CO2. Based on this concept a large number of target formations have been identified and intensively investigated with different types of techniques such as the hydrogeophysical experiments or numerical simulations. The numerical simulations of CO2 migrations in saline formations recently gather much attention because a number of models are available for this purpose and there are potential sites existing in many countries. The lower part of Cholan Formation (CF) near Changhua Coastal Industrial Park (CCIP) in west central Taiwan was identified the largest potential site for CO2 sequestration. The top elevations of the KF in this area varies from 1300 to 1700m below the sea level. Laboratory experiment showed that the permeability of CF is 10-14 to 10-12 m2. Over the years the offshore seismic survey and limited onshore borehole logs have provided information for the simulation of CO2 migration in the CF although the original investigations might not focus on the purpose of CO2 sequestration. In this study we modify the TOUGHREACT model to consider the small-scale heterogeneity in target formation and the cap rock of upper CF. A Monte Carlo Simulation (MCS) approach based on the TOUGHREACT model is employed to quantify the effect of small-scale heterogeneity on the CO2 migrations and hydrochemical reactions in the CF. We assume that the small-scale variability of permeability in KF can be described with a known Gaussian distribution. Therefore, the Gaussian type random field generator such as Sequential Gaussian Simulation (SGSIM) in Geostatistical Software Library (GSLIB) can be used to provide the random permeability realizations for the MCS. A variety of statistical parameters such as the variances and correlation lengths in a Gaussian covariance model are varied in the MCS and the uncertainty of the CO2 and other chemical concentrations are evaluated based on 144 random realizations. In this study a constant injection rate of100Mt/year supercritical CO2 is applied in the bottom of CF. The continuous injection time is 20 years and the uncertainty results are evaluated at 100 years. By comparing with the case without small-scale variability simulation results show that the CO2 plume sizes in the horizontal direction increase from tens of meters to hundreds of meters when the variances of small-scale variability are varied from 1.0 to 4.0. The changes of correlation lengths (i.e., from 100m, 200m, to 400m) show small contribution on the size increases of CO2 plumes. Other uncertainties of chemical concentrations show behaviors similar to the CO2 plume patterns.

Lithium-functionalized germanene: A promising media for CO2 capture

NASA Astrophysics Data System (ADS)

Mehdi Aghaei, S.; Monshi, M. M.; Torres, I.; Banakermani, M.; Calizo, I.

2018-02-01

Density functional theory (DFT) is employed to investigate the interactions of CO2 gas molecules with pristine and lithium-functionalized germanene. It is discovered that although a single CO2 molecule is weakly physisorbed on pristine germanene, a significant improvement on its adsorption energy is found by utilizing Li-functionalized germanene as the adsorbent. Excitingly, the moderate adsorption energy at high CO2 coverage secures an easy release step. Moreover, the structure of Li-functionalized germanene can be fully recovered after removal of CO2 gas molecules. Our results suggest that Li-functionalized germanene show promise for CO2 sensing and capture with a storage capacity of 12.57 mol/kg.

Carbon Capture and Storage (CCS): Risk assessment focused on marine bacteria.

PubMed

Borrero-Santiago, A R; DelValls, T A; Riba, I

2016-09-01

Carbon capture and storage (CCS) is one of the options to mitigate the negative effects of the climate change. However, this strategy may have associated some risks such as CO2 leakages due to an escape from the reservoir. In this context, marine bacteria have been underestimated. In order to figure out the gaps and the lack of knowledge, this work summarizes different studies related to the potential effects on the marine bacteria associated with an acidification caused by a CO2 leak from CSS. An improved integrated model for risk assessment is suggested as a tool based on the rapid responses of bacterial community. Moreover, this contribution proposes a strategy for laboratory protocols using Pseudomona stanieri (CECT7202) as a case of study and analyzes the response of the strain under different CO2 conditions. Results showed significant differences (p≤0.05) under six diluted enriched medium and differences about the days in the exponential growth phase. Dilution 1:10 (Marine Broth 2216 with seawater) was selected as an appropriate growth medium for CO2 toxicity test in batch cultures. This work provide an essential and a complete tool to understand and develop a management strategy to improve future works related to possible effects produced by potential CO2 leaks. Copyright © 2016 Elsevier Inc. All rights reserved.

Hybrid Encapsulated Ionic Liquids for Post-Combustion Carbon Dioxide (CO 2) Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brennecke, Joan; Degnan, Thomas; McCready, Mark

Ionic liquids (ILs) and Phase Change Ionic Liquids (PCILs) are excellent materials for selective removal of carbon dioxide from dilute post-combustion streams. However, they are typically characterized as having high viscosities, which impairs their effectiveness due to mass transfer limitations, caused by the high viscosities. In this project, we are examining the benefits of encapsulating ILs and PCILs in thin polymeric shells to produce particles of approximately 100 to 600 μm in diameter that can be used in a fluidized bed absorber. The particles are produced by microencapsulation of the ILs and PCILs in CO 2-permeable polymer shells. Here wemore » report on the synthesis of the IL and PCIL materials, measurements of thermophysical properties including CO 2 capacity and reprotonation equilibrium and kinetics, encapsulation of the ILs and PCILs, mechanical and thermodynamic testing of the encapsulated materials, development of a rate based model of the absorber, and the design of a laboratory scale unit to test the encapsulated particles for CO 2 capture ability and efficiency. We show that the IL/PCIL materials can be successfully encapsulated, that they retain CO 2 uptake capacity, and that the uptake rates are increased relative to a stagnant sample of IL liquid or PCIL powder.« less

Graphene-based porous silica sheets impregnated with polyethyleneimine for superior CO2 capture.

PubMed

Yang, Shubin; Zhan, Liang; Xu, Xiaoyue; Wang, Yanli; Ling, Licheng; Feng, Xinliang

2013-04-18

It is demonstrated that graphene-based porous silica sheets can serve as an efficient carrier support for PEI via a simple nanocasting technology. The resulting materials possess thin nature, high PEI loading content and high thermal-conductivity. Such features are favorable for the efficient diffusion and adsorption of CO2 as well as the rapid thermal transfer during the CO2 capture process. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Interpretaion of synthetic seismic time-lapse monitoring data for Korea CCS project based on the acoustic-elastic coupled inversion

NASA Astrophysics Data System (ADS)

Oh, J.; Min, D.; Kim, W.; Huh, C.; Kang, S.

2012-12-01

Recently, the CCS (Carbon Capture and Storage) is one of the promising methods to reduce the CO2 emission. To evaluate the success of the CCS project, various geophysical monitoring techniques have been applied. Among them, the time-lapse seismic monitoring is one of the effective methods to investigate the migration of CO2 plume. To monitor the injected CO2 plume accurately, it is needed to interpret seismic monitoring data using not only the imaging technique but also the full waveform inversion, because subsurface material properties can be estimated through the inversion. However, previous works for interpreting seismic monitoring data are mainly based on the imaging technique. In this study, we perform the frequency-domain full waveform inversion for synthetic data obtained by the acoustic-elastic coupled modeling for the geological model made after Ulleung Basin, which is one of the CO2 storage prospects in Korea. We suppose the injection layer is located in fault-related anticlines in the Dolgorae Deformed Belt and, for more realistic situation, we contaminate the synthetic monitoring data with random noise and outliers. We perform the time-lapse full waveform inversion in two scenarios. One scenario is that the injected CO2 plume migrates within the injection layer and is stably captured. The other scenario is that the injected CO2 plume leaks through the weak part of the cap rock. Using the inverted P- and S-wave velocities and Poisson's ratio, we were able to detect the migration of the injected CO2 plume. Acknowledgment This work was financially supported by the Brain Korea 21 project of Energy Systems Engineering, the "Development of Technology for CO2 Marine Geological Storage" program funded by the Ministry of Land, Transport and Maritime Affairs (MLTM) of Korea and the Korea CCS R&D Center (KCRC) grant funded by the Korea government (Ministry of Education, Science and Technology) (No. 2012-0008926).

A first-principles density functional theory study of the electronic structural and thermodynamic properties of M2ZrO3 and M2CO3 (M=Na, K) and their capabilities for CO2 capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuhua Duan

2012-01-01

Alkali metal zirconates could be used as solid sorbents for CO{sub 2} capture. The structural, electronic, and phonon properties of Na{sub 2}ZrO{sub 3}, K{sub 2}ZrO{sub 3}, Na{sub 2}CO{sub 3}, and K{sub 2}CO{sub 3} are investigated by combining the density functional theory with lattice phonon dynamics. The thermodynamics of CO{sub 2} absorption/desorption reactions of these two zirconates are analyzed. The calculated results show that their optimized structures are in a good agreement with experimental measurements. The calculated band gaps are 4.339 eV (indirect), 3.641 eV (direct), 3.935 eV (indirect), and 3.697 eV (direct) for Na{sub 2}ZrO{sub 3}, K{sub 2}ZrO{sub 3}, Na{submore » 2}CO{sub 3}, and K{sub 2}CO{sub 3}, respectively.The calculated phonon dispersions and phonon density of states for M{sub 2}ZrO{sub 3} and M{sub 2}CO{sub 3} (M = K, Na, Li) revealed that from K to Na to Li, their frequency peaks are shifted to high frequencies due to the molecular weight decreased from K to Li. From the calculated reaction heats and relationships of free energy change versus temperatures and CO{sub 2} pressures of the M{sub 2}ZrO{sub 3} (M = K, Na, Li) reacting with CO{sub 2}, we found that the performance of Na{sub 2}ZrO{sub 3} capturing CO{sub 2} is similar to that of Li{sub 2}ZrO{sub 3} and is better than that of K{sub 2}ZrO{sub 3}. Therefore, Na{sub 2}ZrO{sub 3} and Li{sub 2}ZrO{sub 3} are good candidates of high temperature CO{sub 2} sorbents and could be used for post combustion CO{sub 2} capture technologies.« less

Capturing tumor complexity in vitro: Comparative analysis of 2D and 3D tumor models for drug discovery.

PubMed

Stock, Kristin; Estrada, Marta F; Vidic, Suzana; Gjerde, Kjersti; Rudisch, Albin; Santo, Vítor E; Barbier, Michaël; Blom, Sami; Arundkar, Sharath C; Selvam, Irwin; Osswald, Annika; Stein, Yan; Gruenewald, Sylvia; Brito, Catarina; van Weerden, Wytske; Rotter, Varda; Boghaert, Erwin; Oren, Moshe; Sommergruber, Wolfgang; Chong, Yolanda; de Hoogt, Ronald; Graeser, Ralph

2016-07-01

Two-dimensional (2D) cell cultures growing on plastic do not recapitulate the three dimensional (3D) architecture and complexity of human tumors. More representative models are required for drug discovery and validation. Here, 2D culture and 3D mono- and stromal co-culture models of increasing complexity have been established and cross-comparisons made using three standard cell carcinoma lines: MCF7, LNCaP, NCI-H1437. Fluorescence-based growth curves, 3D image analysis, immunohistochemistry and treatment responses showed that end points differed according to cell type, stromal co-culture and culture format. The adaptable methodologies described here should guide the choice of appropriate simple and complex in vitro models.

Capturing tumor complexity in vitro: Comparative analysis of 2D and 3D tumor models for drug discovery

PubMed Central

Stock, Kristin; Estrada, Marta F.; Vidic, Suzana; Gjerde, Kjersti; Rudisch, Albin; Santo, Vítor E.; Barbier, Michaël; Blom, Sami; Arundkar, Sharath C.; Selvam, Irwin; Osswald, Annika; Stein, Yan; Gruenewald, Sylvia; Brito, Catarina; van Weerden, Wytske; Rotter, Varda; Boghaert, Erwin; Oren, Moshe; Sommergruber, Wolfgang; Chong, Yolanda; de Hoogt, Ronald; Graeser, Ralph

2016-01-01

Two-dimensional (2D) cell cultures growing on plastic do not recapitulate the three dimensional (3D) architecture and complexity of human tumors. More representative models are required for drug discovery and validation. Here, 2D culture and 3D mono- and stromal co-culture models of increasing complexity have been established and cross-comparisons made using three standard cell carcinoma lines: MCF7, LNCaP, NCI-H1437. Fluorescence-based growth curves, 3D image analysis, immunohistochemistry and treatment responses showed that end points differed according to cell type, stromal co-culture and culture format. The adaptable methodologies described here should guide the choice of appropriate simple and complex in vitro models. PMID:27364600

Analysis of the Potential Impact of Discrepancies in Stratosphere-troposphere Exchange on Inferred Sources and Sinks of CO2

NASA Astrophysics Data System (ADS)

Jones, D. B. A.; Deng, F.; Walker, T. W.; Keller, M.; Bowman, K. W.; Nassar, R.

2014-12-01

The upper troposphere and lower stratosphere (UTLS) represents a transition region between the more dynamically active troposphere and more stably stratified stratosphere. The processes that influence the distribution of atmospheric constituents in the UTLS occur on small vertical scales that are a challenge for models to reliably capture. As a consequence, models typically underestimate the mean age of air in the lowermost stratosphere, reflecting excessive vertical transport and/or mixing in the region. Using the GEOS-Chem global chemical transport model, we quantify the potential impact of discrepancies in vertical transport in the UTLS on inferred sources and sinks of atmospheric CO2. Comparisons of the modeled CO2 and O3 in the polar UTLS with data from the HIAPER Pole-to-Pole Observations (HIPPO) campaign show that the model overestimates CO2 and underestimates O3 in the region. Using the observed CO2/O3 correlations in the UTLS, we correct the modeled CO2 in the Arctic UTLS (primarily between the 320 K and 360 K isentropic surfaces) and quantify the impact of the CO2 correction on the flux estimates using the GEOS-Chem data assimilation system together with XCO2 data from the Greenhouse Gases Observing Satellite (GOSAT). As a result of isentropic transport, the correction is transported down into the subtropical troposphere, where it impacts the regional flux estimates. Our results suggest that discrepancies in mixing in the UTLS could bias the latitudinal distribution of the inferred CO2 fluxes.

Role of amine structure on carbon dioxide adsorption from ultradilute gas streams such as ambient air.

PubMed

Didas, Stephanie A; Kulkarni, Ambarish R; Sholl, David S; Jones, Christopher W

2012-10-01

A fundamental study on the adsorption properties of primary, secondary, and tertiary amine materials is used to evaluate what amine type(s) are best suited for ultradilute CO(2) capture applications. A series of comparable materials comprised of primary, secondary, or tertiary amines ligated to a mesoporous silica support via a propyl linker are used to systematically assess the role of amine type. Both CO(2) and water adsorption isotherms are presented for these materials in the range relevant to CO(2) capture from ambient air and it is demonstrated that primary amines are the best candidates for CO(2) capture from air. Primary amines possess both the highest amine efficiency for CO(2) adsorption as well as enhanced water affinity compared to other amine types or the bare silica support. The results suggest that the rational design of amine adsorbents for the extraction of CO(2) from ambient air should focus on adsorbents rich in primary amines. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Joint Evaluation of Copernicus Atmosphere Monitoring Service (CAMS) High-resolution Global Near-Real Time CO and CO2 Forecasts during KORUS-AQ Field Campaign

NASA Astrophysics Data System (ADS)

Tang, W.; Arellano, A. F., Jr.; Choi, Y.; DiGangi, J. P.; Woo, J. H.; Diskin, G. S.; Agusti-panareda, A.; Parrington, M.; Massart, S.; Lee, M.; Kanaya, Y.; Jang, J.; Lee, Y.; Hong, J.; Flynn, J. H., III; Thompson, A. M.; Kim, D. B.

2017-12-01

Anthropogenic combustion has significant impacts on air quality and climate. To understand anthropogenic combustion, it is critical to model CO2 and CO (key combustion signatures) and their relationships. In this study, we jointly evaluate the Copernicus Atmosphere Monitoring Service (CAMS) free-running 16-km forecast, 9-km forecast initialized with CAMS analysis, and analysis products of CO (80km) and CO2 (40km) to understand how well combustion-related processes and constituent transport are represented in the current system. We use measurements from aircraft, ground sites, and ships during the KORUS-AQ field campaign (May - June 2016), along with satellite observations (MOPITT, IASI, OCO-2, and GOSAT). Airborne measurements by the DC-8 aircraft are classified into five regions: Seoul metropolitan, Taehwa, West Sea, Seoul-Jeju jetway, and Seoul-Busan jetway. The observed CO2, CO, and their relationships varies significantly, and the performance of CAMS products also varies across regions. The three CAMS products perform reasonably well in simulating anthropogenic combustion processes. Overall, CO2 is overestimated while CO is underestimated by CAMS. The 9km forecast product generally has a better performance than the other two, because of its higher model resolution and better initialization conditions. The analysis product also performs better than the 16km forecast. China outflow over West Sea is captured, but CO2 and CO is underestimated in the outflow. According to CAMS, is 10-15 (ppbv/ppmv) for Korea and about 30 for China outflow, indicating anthropogenic combustion in Seoul is more efficient than it is in China. This agrees well with DC-8 aircraft observations. As for ground sites, we find that CO and CO2 measured by the Olympic park and Yonsei (Seoul metropolitan sites) have more regularity in diurnal cycle, and such periodical change is well captured by CAMS. The time series for CO from Baengnyeong, and Fukue (remote sites) are irregular and episodic, which are more related to transport rather than local emissions. CAMS performances over Taehwa site are impacted by both local processes and transport. These comparisons indicate vertical mixing near sources may be an issue for CAMS. Compared to satellite observations, CO analyses show a better agreement, while for CO2, the forecasts are better.

Carbon Dioxide Separation from Flue Gases: A Technological Review Emphasizing Reduction in Greenhouse Gas Emissions

PubMed Central

Songolzadeh, Mohammad; Soleimani, Mansooreh; Takht Ravanchi, Maryam; Songolzadeh, Reza

2014-01-01

Increasing concentrations of greenhouse gases (GHGs) such as CO2 in the atmosphere is a global warming. Human activities are a major cause of increased CO2 concentration in atmosphere, as in recent decade, two-third of greenhouse effect was caused by human activities. Carbon capture and storage (CCS) is a major strategy that can be used to reduce GHGs emission. There are three methods for CCS: pre-combustion capture, oxy-fuel process, and post-combustion capture. Among them, post-combustion capture is the most important one because it offers flexibility and it can be easily added to the operational units. Various technologies are used for CO2 capture, some of them include: absorption, adsorption, cryogenic distillation, and membrane separation. In this paper, various technologies for post-combustion are compared and the best condition for using each technology is identified. PMID:24696663

Carbon dioxide separation from flue gases: a technological review emphasizing reduction in greenhouse gas emissions.

PubMed

Songolzadeh, Mohammad; Soleimani, Mansooreh; Takht Ravanchi, Maryam; Songolzadeh, Reza

2014-01-01

Increasing concentrations of greenhouse gases (GHGs) such as CO2 in the atmosphere is a global warming. Human activities are a major cause of increased CO2 concentration in atmosphere, as in recent decade, two-third of greenhouse effect was caused by human activities. Carbon capture and storage (CCS) is a major strategy that can be used to reduce GHGs emission. There are three methods for CCS: pre-combustion capture, oxy-fuel process, and post-combustion capture. Among them, post-combustion capture is the most important one because it offers flexibility and it can be easily added to the operational units. Various technologies are used for CO2 capture, some of them include: absorption, adsorption, cryogenic distillation, and membrane separation. In this paper, various technologies for post-combustion are compared and the best condition for using each technology is identified.

High capacity immobilized amine sorbents

DOEpatents

Gray, McMahan L [Pittsburgh, PA; Champagne, Kenneth J [Fredericktown, PA; Soong, Yee [Monroeville, PA; Filburn, Thomas [Granby, CT

2007-10-30

A method is provided for making low-cost CO.sub.2 sorbents that can be used in large-scale gas-solid processes. The improved method entails treating an amine to increase the number of secondary amine groups and impregnating the amine in a porous solid support. The method increases the CO.sub.2 capture capacity and decreases the cost of utilizing an amine-enriched solid sorbent in CO.sub.2 capture systems.

Role of Additives in Composite PEI/Oxide CO 2 Adsorbents: Enhancement in the Amine Efficiency of Supported PEI by PEG in CO 2 Capture from Simulated Ambient Air

DOE PAGES

Sakwa-Novak, Miles A.; Tan, Shuai; Jones, Christopher W.

2015-10-20

Supported amines are promising candidate adsorbents for the removal of CO 2 from flue gases and directly from ambient air. The incorporation of additives into polymeric amines such as poly(ethylenimine) (PEI) supported on mesoporous oxides is an effective strategy to improve the performance of the materials. Here, several practical aspects of this strategy are addressed with regards to direct air capture. The influence of three additives (CTAB, PEG200, PEG1000) was systematically explored under dry simulated air capture conditions (400 ppm of CO 2, 30 °C). With SBA-15 as a model support for poly(ethylenimine) (PEI), the nature of the additive inducedmore » heterogeneities in the deposition of organic on the interior and exterior of the particles, an important consideration for future scale up to practical systems. The PEG200 additive increased the observed thermodynamic performance (~60% increase in amine efficiency) of the adsorbents regardless of the PEI content, while the other molecules had less positive effects. A threshold PEG200/PEI value was identified at which the diffusional limitations of CO 2 within the materials were nearly eliminated. The threshold PEG/PEI ratio may have physical origin in the interactions between PEI and PEG, as the optimal ratio corresponded to nearly equimolar OH/reactive (1°, 2°) amine ratios. As a result, the strategy is shown to be robust to the characteristics of the host support, as PEG200 improved the amine efficiency of PEI when supported on two varieties of mesoporous γ-alumina with PEI.« less

Role of Additives in Composite PEI/Oxide CO 2 Adsorbents: Enhancement in the Amine Efficiency of Supported PEI by PEG in CO 2 Capture from Simulated Ambient Air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sakwa-Novak, Miles A.; Tan, Shuai; Jones, Christopher W.

Supported amines are promising candidate adsorbents for the removal of CO 2 from flue gases and directly from ambient air. The incorporation of additives into polymeric amines such as poly(ethylenimine) (PEI) supported on mesoporous oxides is an effective strategy to improve the performance of the materials. Here, several practical aspects of this strategy are addressed with regards to direct air capture. The influence of three additives (CTAB, PEG200, PEG1000) was systematically explored under dry simulated air capture conditions (400 ppm of CO 2, 30 °C). With SBA-15 as a model support for poly(ethylenimine) (PEI), the nature of the additive inducedmore » heterogeneities in the deposition of organic on the interior and exterior of the particles, an important consideration for future scale up to practical systems. The PEG200 additive increased the observed thermodynamic performance (~60% increase in amine efficiency) of the adsorbents regardless of the PEI content, while the other molecules had less positive effects. A threshold PEG200/PEI value was identified at which the diffusional limitations of CO 2 within the materials were nearly eliminated. The threshold PEG/PEI ratio may have physical origin in the interactions between PEI and PEG, as the optimal ratio corresponded to nearly equimolar OH/reactive (1°, 2°) amine ratios. As a result, the strategy is shown to be robust to the characteristics of the host support, as PEG200 improved the amine efficiency of PEI when supported on two varieties of mesoporous γ-alumina with PEI.« less

The Description and Validation of a Computationally-Efficient CH4-CO-OH (ECCOHv1.01) Chemistry Module for 3D Model Applications

NASA Technical Reports Server (NTRS)

Elshorbany, Yasin F.; Duncan, Bryan N.; Strode, Sarah A.; Wang, James S.; Kouatchou, Jules

2016-01-01

We present the Efficient CH4-CO-OH (ECCOH) chemistry module that allows for the simulation of the methane, carbon monoxide, and hydroxyl radical (CH4-CO- OH) system, within a chemistry climate model, carbon cycle model, or Earth system model. The computational efficiency of the module allows many multi-decadal sensitivity simulations of the CH4-CO-OH system, which primarily determines the global atmospheric oxidizing capacity. This capability is important for capturing the nonlinear feedbacks of the CH4-CO-OH system and understanding the perturbations to methane, CO, and OH, and the concomitant impacts on climate. We implemented the ECCOH chemistry module in the NASA GEOS-5 atmospheric global circulation model (AGCM), performed multiple sensitivity simulations of the CH4-CO-OH system over 2 decades, and evaluated the model output with surface and satellite data sets of methane and CO. The favorable comparison of output from the ECCOH chemistry module (as configured in the GEOS- 5 AGCM) with observations demonstrates the fidelity of the module for use in scientific research.

Hydroquinone and Quinone-Grafted Porous Carbons for Highly Selective CO2 Capture from Flue Gases and Natural Gas Upgrading.

PubMed

Wang, Jun; Krishna, Rajamani; Yang, Jiangfeng; Deng, Shuguang

2015-08-04

Hydroquinone and quinone functional groups were grafted onto a hierarchical porous carbon framework via the Friedel-Crafts reaction to develop more efficient adsorbents for the selective capture and removal of carbon dioxide from flue gases and natural gas. The oxygen-doped porous carbons were characterized with scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. CO2, CH4, and N2 adsorption isotherms were measured and correlated with the Langmuir model. An ideal adsorbed solution theory (IAST) selectivity for the CO2/N2 separation of 26.5 (298 K, 1 atm) was obtained on the hydroquinone-grafted carbon, which is 58.7% higher than that of the pristine porous carbon, and a CO2/CH4 selectivity value of 4.6 (298 K, 1 atm) was obtained on the quinone-grafted carbon (OAC-2), which represents a 28.4% improvement over the pristine porous carbon. The highest CO2 adsorption capacity on the oxygen-doped carbon adsorbents is 3.46 mmol g(-1) at 298 K and 1 atm. In addition, transient breakthrough simulations for CO2/CH4/N2 mixture separation were conducted to demonstrate the good separation performance of the oxygen-doped carbons in fixed bed adsorbers. Combining excellent adsorption separation properties and low heats of adsorption, the oxygen-doped carbons developed in this work appear to be very promising for flue gas treatment and natural gas upgrading.

Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO 2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kathe, Mandar; Xu, Dikai; Hsieh, Tien-Lin

2014-12-31

This document is the final report for the project titled “Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO 2 Capture” under award number FE0012136 for the performance period 10/01/2013 to 12/31/2014.This project investigates the novel Ohio State chemical looping gasification technology for high efficiency, cost efficiency coal gasification for IGCC and methanol production application. The project developed an optimized oxygen carrier composition, demonstrated the feasibility of the concept and completed cold-flow model studies. WorleyParsons completed a techno-economic analysis which showed that for a coal only feed with carbon capture, the OSU CLG technology reduced the methanol requiredmore » selling price by 21%, lowered the capital costs by 28%, increased coal consumption efficiency by 14%. Further, using the Ohio State Chemical Looping Gasification technology resulted in a methanol required selling price which was lower than the reference non-capture case.« less

Mesoscale carbon sequestration site screening and CCS infrastructure analysis.

PubMed

Keating, Gordon N; Middleton, Richard S; Stauffer, Philip H; Viswanathan, Hari S; Letellier, Bruce C; Pasqualini, Donatella; Pawar, Rajesh J; Wolfsberg, Andrew V

2011-01-01

We explore carbon capture and sequestration (CCS) at the meso-scale, a level of study between regional carbon accounting and highly detailed reservoir models for individual sites. We develop an approach to CO(2) sequestration site screening for industries or energy development policies that involves identification of appropriate sequestration basin, analysis of geologic formations, definition of surface sites, design of infrastructure, and analysis of CO(2) transport and storage costs. Our case study involves carbon management for potential oil shale development in the Piceance-Uinta Basin, CO and UT. This study uses new capabilities of the CO(2)-PENS model for site screening, including reservoir capacity, injectivity, and cost calculations for simple reservoirs at multiple sites. We couple this with a model of optimized source-sink-network infrastructure (SimCCS) to design pipeline networks and minimize CCS cost for a given industry or region. The CLEAR(uff) dynamical assessment model calculates the CO(2) source term for various oil production levels. Nine sites in a 13,300 km(2) area have the capacity to store 6.5 GtCO(2), corresponding to shale-oil production of 1.3 Mbbl/day for 50 years (about 1/4 of U.S. crude oil production). Our results highlight the complex, nonlinear relationship between the spatial deployment of CCS infrastructure and the oil-shale production rate.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brodsky, Casey N.; Hadt, Ryan G.; Hayes, Dugan

The Co 4O 4 cubane is a representative structural model of oxidic cobalt oxygen evolving catalysts (Co-OECs). The Co-OECs are active when residing at two oxidation levels above an all Co(III) resting state. This doubly oxidized Co(IV) 2 state may be captured in a Co(III) 2(IV) 2 cubane. We demonstrate that the Co(III) 2(IV) 2 cubane may be electrochemically generated and the electronic properties of this unique high-valent state may be probed by in situ spectroscopy. Intervalence charge transfer (IVCT) bands in the near-IR are observed for the Co(III) 2(IV) 2 cubane, and spectroscopic analysis together with electrochemical kinetics measurementsmore » reveal a larger reorganization energy and a smaller electron transfer rate constant for the doubly versus singly oxidized cubane. Spectroelectrochemical X-ray absorption data further reveal systematic spectral changes with successive oxidations from the cubane resting state. Electronic structure calculations correlated to experimental data suggest that this state is best represented as a localized, antiferromagnetically coupled Co(IV) 2 dimer. The exchange coupling in the cofacial Co(IV) 2 site allows for parallels to be drawn between the electronic structure of the Co 4O 4 cubane model system and the high valent active site of the Co-OEC, with specific emphasis on the manifestation of a doubly oxidized Co(IV) 2 center on O–O bond formation.« less

Pore-scale simulation of CO2-water-rock interactions

NASA Astrophysics Data System (ADS)

Deng, H.; Molins, S.; Steefel, C. I.; DePaolo, D. J.

2017-12-01

In Geologic Carbon Storage (GCS) systems, the migration of scCO2 versus CO2-acidifed brine ultimately determines the extent of mineral trapping and caprock integrity, i.e. the long-term storage efficiency and security. While continuum scale multiphase reactive transport models are valuable for large scale investigations, they typically (over-)simplify pore-scale dynamics and cannot capture local heterogeneities that may be important. Therefore, pore-scale models are needed in order to provide mechanistic understanding of how fine scale structural variations and heterogeneous processes influence the transport and geochemistry in the context of multiphase flow, and to inform parameterization of continuum scale modeling. In this study, we investigate the interplay of different processes at pore scale (e.g. diffusion, reactions, and multiphase flow) through the coupling of a well-developed multiphase flow simulator with a sophisticated reactive transport code. The objectives are to understand where brine displaced by scCO2 will reside in a rough pore/fracture, and how the CO2-water-rock interactions may affect the redistribution of different phases. In addition, the coupled code will provide a platform for model testing in pore-scale multiphase reactive transport problems.

Hopewell Beneficial CO2 Capture for Production of Fuels, Fertilizer and Energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

UOP; Honeywell Resins & Chemicals; Honeywell Process Solutions

2010-09-30

For Phase 1 of this project, the Hopewell team developed a detailed design for the Small Scale Pilot-Scale Algal CO2 Sequestration System. This pilot consisted of six (6) x 135 gallon cultivation tanks including systems for CO2 delivery and control, algal cultivation, and algal harvesting. A feed tank supplied Hopewell wastewater to the tanks and a receiver tank collected the effluent from the algal cultivation system. The effect of environmental parameters and nutrient loading on CO2 uptake and sequestration into biomass were determined. Additionally the cost of capturing CO2 from an industrial stack emission at both pilot and full-scale wasmore » determined. The engineering estimate evaluated Amine Guard technology for capture of pure CO2 and direct stack gas capture and compression. The study concluded that Amine Guard technology has lower lifecycle cost at commercial scale, although the cost of direct stack gas capture is lower at the pilot scale. Experiments conducted under high concentrations of dissolved CO2 did not demonstrate enhanced algae growth rate. This result suggests that the dissolved CO2 concentration at neutral pH was already above the limiting value. Even though dissolved CO2 did not show a positive effect on biomass growth, controlling its value at a constant set-point during daylight hours can be beneficial in an algae cultivation stage with high algae biomass concentration to maximize the rate of CO2 uptake. The limited enhancement of algal growth by CO2 addition to Hopewell wastewater was due at least in part to the high endogenous CO2 evolution from bacterial degradation of dissolved organic carbon present at high levels in the wastewater. It was found that the high level of bacterial activity was somewhat inhibitory to algal growth in the Hopewell wastewater. The project demonstrated that the Honeywell automation and control system, in combination with the accuracy of the online pH, dissolved O2, dissolved CO2, turbidity, Chlorophyll A and conductivity sensors is suitable for process control of algae cultivation in an open pond systems. This project concluded that the Hopewell wastewater is very suitable for algal cultivation but the potential for significant CO2 sequestration from the plant stack gas emissions was minimal due to the high endogenous CO2 generation in the wastewater from the organic wastewater content. Algae cultivation was found to be promising, however, for nitrogen remediation in the Hopewell wastewater.« less

Environmental potential of the use of CO2 from alcoholic fermentation processes. The CO2-AFP strategy.

PubMed

Alonso-Moreno, Carlos; García-Yuste, Santiago

2016-10-15

A novel Carbon Dioxide Utilization (CDU) approach from a relatively minor CO2 emission source, i.e., alcoholic fermentation processes (AFP), is presented. The CO2 produced as a by-product from the AFP is estimated by examining the EtOH consumed per year reported by the World Health Organization in 2014. It is proposed that the extremely pure CO2 from the AFP is captured in NaOH solutions to produce one of the Top 10 commodities in the chemical industry, Na2CO3, as a good example of an atomic economy process. The novel CDU strategy could yield over 30.6Mt of Na2CO3 in oversaturated aqueous solution on using ca. 12.7Mt of captured CO2 and this process would consume less energy than the synthetic methodology (Solvay ammonia soda process) and would not produce low-value by-products. The quantity of Na2CO3 obtained by this strategy could represent ca. 50% of the world Na2CO3 production in one year. In terms of the green economy, the viability of the strategy is discussed according to the recommendations of the CO2Chem network, and an estimation of the CO2negative emission achieved suggests a capture of around 280.0Mt of CO2 from now to 2020 or ca. 1.9Gt from now to 2050. Finally, the results obtained for this new CDU proposal are discussed by considering different scenarios; the CO2 production in a typical winemaking corporation, the CO2 released in the most relevant wine-producing countries, and the use of CO2 from AFP as an alternative for the top Na2CO3-producing countries. Copyright © 2016 Elsevier B.V. All rights reserved.

Synthesis of sintering-resistant sorbents for CO2 capture.

PubMed

Liu, Wenqiang; Feng, Bo; Wu, Yueqin; Wang, Guoxiong; Barry, John; da Costa, João C Diniz

2010-04-15

Sorbents for high temperature CO2 capture are under intensive development owing to their potential applications in advanced zero emission power, sorption-enhanced steam methane reforming for hydrogen production and energy storage systems in chemical heat pumps. One of the challenges in the development is the prevention of sintering of the sorbent (normally a calcium oxide derivative) which causes the CO2 capture capacity of the material to deteriorate rapidly after a few cycles of utilization. Here we show that a simple wet mixing method can produce sintering-resistant sorbents from calcium and magnesium salts of d-gluconic acid. It was found that calcium oxide was well distributed in the sorbents with metal oxide nanoparticles on the surface acting as physical barriers, and the CO2 capture capacity of the sorbents was largely maintained over multiple cycles of utilization. This method was also applied to other organometallic salts of calcium and magnesium/aluminum and the produced sorbents showed similarly high reversibility.

Application of halloysite nanotubes for carbon dioxide capture

NASA Astrophysics Data System (ADS)

Kim, Jinsoo; Rubino, Ilaria; Lee, Joo-Youp; Choi, Hyo-Jick

2016-04-01

Halloysite is a naturally occurring clay, with physical structure represented by halloysite nanotubes (HNTs). We investigated the potential applicability of HNTs for carbon dioxide (CO2) capture, using two amine-functionalized HNTs: (3-aminopropyl) triethoxysilane (APTES)-grafted HNTs and polyethylenimine (PEI)-impregnated HNTs. APTES-HNTs and PEI-HNTs resulted in 5.6 and 30 wt. % (in sorbent) in functionalization onto HNTs, respectively. Capture efficiency was higher in APTES-HNTs at lower temperatures, while it was maximum in PEI-HNTs at 70°C-75 °C. At 75 °C, adsorption/desorption tests showed that 95% of the two reactions occurred within 30 min, and exhibited 0.15 and 0.21 millimole of CO2 adsorption capacity per millimole of amine group for APTES-HNTs and PEI-HNTs, respectively. During 10 cycles of CO2 adsorption/desorption, there was no significant decrease in sorbent weight and adsorption capacity in both HNTs. These results show that inherent structural features of HNTs can be easily tailored for the development of operational condition-specific CO2 capture system.

Integrated CO2 capture-fixation chemistry via interfacial ionic liquid catalyst in laminar gas/liquid flow

NASA Astrophysics Data System (ADS)

Vishwakarma, Niraj K.; Singh, Ajay K.; Hwang, Yoon-Ho; Ko, Dong-Hyeon; Kim, Jin-Oh; Babu, A. Giridhar; Kim, Dong-Pyo

2017-03-01

Simultaneous capture of carbon dioxide (CO2) and its utilization with subsequent work-up would significantly enhance the competitiveness of CO2-based sustainable chemistry over petroleum-based chemistry. Here we report an interfacial catalytic reaction platform for an integrated autonomous process of simultaneously capturing/fixing CO2 in gas-liquid laminar flow with subsequently providing a work-up step. The continuous-flow microreactor has built-in silicon nanowires (SiNWs) with immobilized ionic liquid catalysts on tips of cone-shaped nanowire bundles. Because of the superamphiphobic SiNWs, a stable gas-liquid interface maintains between liquid flow of organoamines in upper part and gas flow of CO2 in bottom part of channel. The intimate and direct contact of the binary reagents leads to enhanced mass transfer and facilitating reactions. The autonomous integrated platform produces and isolates 2-oxazolidinones and quinazolines-2,4(1H,3H)-diones with 81-97% yields under mild conditions. The platform would enable direct CO2 utilization to produce high-valued specialty chemicals from flue gases without pre-separation and work-up steps.

Integrated CO2 capture-fixation chemistry via interfacial ionic liquid catalyst in laminar gas/liquid flow.

PubMed

Vishwakarma, Niraj K; Singh, Ajay K; Hwang, Yoon-Ho; Ko, Dong-Hyeon; Kim, Jin-Oh; Babu, A Giridhar; Kim, Dong-Pyo

2017-03-06

Simultaneous capture of carbon dioxide (CO 2 ) and its utilization with subsequent work-up would significantly enhance the competitiveness of CO 2 -based sustainable chemistry over petroleum-based chemistry. Here we report an interfacial catalytic reaction platform for an integrated autonomous process of simultaneously capturing/fixing CO 2 in gas-liquid laminar flow with subsequently providing a work-up step. The continuous-flow microreactor has built-in silicon nanowires (SiNWs) with immobilized ionic liquid catalysts on tips of cone-shaped nanowire bundles. Because of the superamphiphobic SiNWs, a stable gas-liquid interface maintains between liquid flow of organoamines in upper part and gas flow of CO 2 in bottom part of channel. The intimate and direct contact of the binary reagents leads to enhanced mass transfer and facilitating reactions. The autonomous integrated platform produces and isolates 2-oxazolidinones and quinazolines-2,4(1H,3H)-diones with 81-97% yields under mild conditions. The platform would enable direct CO 2 utilization to produce high-valued specialty chemicals from flue gases without pre-separation and work-up steps.

Integrated CO2 capture-fixation chemistry via interfacial ionic liquid catalyst in laminar gas/liquid flow

PubMed Central

Vishwakarma, Niraj K.; Singh, Ajay K.; Hwang, Yoon-Ho; Ko, Dong-Hyeon; Kim, Jin-Oh; Babu, A. Giridhar; Kim, Dong-Pyo

2017-01-01

Simultaneous capture of carbon dioxide (CO2) and its utilization with subsequent work-up would significantly enhance the competitiveness of CO2-based sustainable chemistry over petroleum-based chemistry. Here we report an interfacial catalytic reaction platform for an integrated autonomous process of simultaneously capturing/fixing CO2 in gas–liquid laminar flow with subsequently providing a work-up step. The continuous-flow microreactor has built-in silicon nanowires (SiNWs) with immobilized ionic liquid catalysts on tips of cone-shaped nanowire bundles. Because of the superamphiphobic SiNWs, a stable gas–liquid interface maintains between liquid flow of organoamines in upper part and gas flow of CO2 in bottom part of channel. The intimate and direct contact of the binary reagents leads to enhanced mass transfer and facilitating reactions. The autonomous integrated platform produces and isolates 2-oxazolidinones and quinazolines-2,4(1H,3H)-diones with 81–97% yields under mild conditions. The platform would enable direct CO2 utilization to produce high-valued specialty chemicals from flue gases without pre-separation and work-up steps. PMID:28262667

Asphalt-derived high surface area activated porous carbons for carbon dioxide capture.

PubMed

Jalilov, Almaz S; Ruan, Gedeng; Hwang, Chih-Chau; Schipper, Desmond E; Tour, Josiah J; Li, Yilun; Fei, Huilong; Samuel, Errol L G; Tour, James M

2015-01-21

Research activity toward the development of new sorbents for carbon dioxide (CO2) capture have been increasing quickly. Despite the variety of existing materials with high surface areas and high CO2 uptake performances, the cost of the materials remains a dominant factor in slowing their industrial applications. Here we report preparation and CO2 uptake performance of microporous carbon materials synthesized from asphalt, a very inexpensive carbon source. Carbonization of asphalt with potassium hydroxide (KOH) at high temperatures (>600 °C) yields porous carbon materials (A-PC) with high surface areas of up to 2780 m(2) g(-1) and high CO2 uptake performance of 21 mmol g(-1) or 93 wt % at 30 bar and 25 °C. Furthermore, nitrogen doping and reduction with hydrogen yields active N-doped materials (A-NPC and A-rNPC) containing up to 9.3% nitrogen, making them nucleophilic porous carbons with further increase in the Brunauer-Emmett-Teller (BET) surface areas up to 2860 m(2) g(-1) for A-NPC and CO2 uptake to 26 mmol g(-1) or 114 wt % at 30 bar and 25 °C for A-rNPC. This is the highest reported CO2 uptake among the family of the activated porous carbonaceous materials. Thus, the porous carbon materials from asphalt have excellent properties for reversibly capturing CO2 at the well-head during the extraction of natural gas, a naturally occurring high pressure source of CO2. Through a pressure swing sorption process, when the asphalt-derived material is returned to 1 bar, the CO2 is released, thereby rendering a reversible capture medium that is highly efficient yet very inexpensive.

Development of a carbonate absorption-based process for post-combustion CO2 capture: The role of biocatalyst to promote CO2 absorption rate

USGS Publications Warehouse

Lu, Y.; Ye, X.; Zhang, Z.; Khodayari, A.; Djukadi, T.

2011-01-01

An Integrated Vacuum Carbonate Absorption Process (IVCAP) for post-combustion carbon dioxide (CO2) capture is described. IVCAP employs potassium carbonate (PC) as a solvent, uses waste or low quality steam from the power plant for CO2 stripping, and employs a biocatalyst, carbonic anhydrase (CA) enzyme, for promoting the CO2 absorption into PC solution. A series of experiments were performed to evaluate the activity of CA enzyme mixed in PC solutions in a stirred tank reactor system under various temperatures, CA dosages, CO2 loadings, CO2 partial pressures, and the presence of major flue gas contaminants. It was demonstrated that CA enzyme is an effective biocatalyst for CO2 absorption under IVCAP conditions. ?? 2011 Published by Elsevier Ltd.

Potentiel des méthodes de séparation et stockage du CO2 dans la lutte contre l'effet de serreThe role of CO2 capture and sequestration in mitigation of climate change

NASA Astrophysics Data System (ADS)

Jean-Baptiste, Philippe; Ducroux, René

2003-06-01

Increasing atmospheric level of greenhouse gases are causing global warming and putting at risk the global climate system. The main anthropogenic greenhouse gas is CO 2. Technical solutions exist to reduce CO 2 emission and stabilise atmospheric CO 2 concentration, including energy saving and energy efficiency, switch to lower carbon content fuels like natural gas and to energy sources that operate with zero CO 2 emissions such as renewable or nuclear energy, enhance the natural sinks for CO 2 (forests, soils, etc.), and last but not least, sequester CO 2 from fossil fuels combustion. The purpose of this paper is to provide an overview of the technology and cost for capture and storage of CO 2. Some of the factors that will influence application, including environmental impact, cost and efficiency, are also discussed. Capturing CO 2 and storing it in underground geological reservoirs appears as the best environmentally acceptable option. It can be done with existing technology; however, substantial R&D is needed to improve available technology and to lower the cost. Applicable to large CO 2 emitting industrial facilities such as power plants, cement factories, steel industry, etc., which amount to more than 30% of the global anthropogenic CO 2 emission, it represents a valuable tool in the battle against global warming. To cite this article: P. Jean-Baptiste, R. Ducroux, C. R. Geoscience 335 (2003).

The Kinetics and Thermodynamics of CO2 Capture by Aqueous Ammonia Derived Using Meta-GGA Density Functional Theory and Wavefunction-Based Model Chemistry Methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beste, Ariana; Attalla, Moetaz; Jackson, Phil

2012-01-01

A meta GGA-DFT study of CO{sub 2} activation in aqueous ammonia solutions, with an emphasis on the reaction barrier and molecularity, has been undertaken using the M06-2X functional with an augmented triple-zeta split-valence basis set (6-311++G(d,p)). Up to five base molecules were treated explicitly in order to establish the effects of solvent catalysis in the chemical capture process. Aqueous free energies of solvation were determined for optimized reactant and transition structures using SM8/M06-2X/6-311++G(d,p). The concept of the solvent pre-complex as presented by Dixon and coworkers (Nguyen, M. T.; Matus, M. H.; Jackson, V. E.; Ngan, V. T.; Rustad, J. R.;more » Dixon, D. A. J. Phys. Chem. A 2008, 112, 10386-10398) was exploited to account for the energetics of disruption of the hydrogen-bonding solvent nano-network prior to the CO{sub 2} activation step. Selected gas- and aqueous-phase thermodynamic quantities have also been derived.« less

Multiphase, multicomponent simulations and experiments of reactive flow, relevant for combining geologic CO2 sequestration with geothermal energy capture

NASA Astrophysics Data System (ADS)

Saar, Martin O.

2011-11-01

Understanding the fluid dynamics of supercritical carbon dioxide (CO2) in brine- filled porous media is important for predictions of CO2 flow and brine displacement during geologic CO2 sequestration and during geothermal energy capture using sequestered CO2 as the subsurface heat extraction fluid. We investigate multiphase fluid flow in porous media employing particle image velocimetry experiments and lattice-Boltzmann fluid flow simulations at the pore scale. In particular, we are interested in the motion of a drop (representing a CO2 bubble) through an orifice in a plate, representing a simplified porous medium. In addition, we study single-phase/multicomponent reactive transport experimentally by injecting water with dissolved CO2 into rocks/sediments typically considered for CO2 sequestration to investigate how resultant fluid-mineral reactions modify permeability fields. Finally, we investigate numerically subsurface CO2 and heat transport at the geologic formation scale.

Atmospheric measurement of point source fossil CO2 emissions

NASA Astrophysics Data System (ADS)

Turnbull, J. C.; Keller, E. D.; Baisden, T.; Brailsford, G.; Bromley, T.; Norris, M.; Zondervan, A.

2014-05-01

We use the Kapuni Gas Treatment Plant to examine methodologies for atmospheric monitoring of point source fossil fuel CO2 (CO2ff) emissions. The Kapuni plant, located in rural New Zealand, removes CO2 from locally extracted natural gas and vents that CO2 to the atmosphere, at a rate of ~0.1 Tg carbon per year. The plant is located in a rural dairy farming area, with no other significant CO2ff sources nearby, but large, diurnally varying, biospheric CO2 fluxes from the surrounding highly productive agricultural grassland. We made flask measurements of CO2 and 14CO2 (from which we derive the CO2ff component) and in situ measurements of CO2 downwind of the Kapuni plant, using a Helikite to sample transects across the emission plume from the surface up to 100 m above ground level. We also determined the surface CO2ff content averaged over several weeks from the 14C content of grass samples collected from the surrounding area. We use the WindTrax plume dispersion model to compare the atmospheric observations with the emissions reported by the Kapuni plant, and to determine how well atmospheric measurements can constrain the emissions. The model has difficulty accurately capturing the fluctuations and short-term variability in the Helikite samples, but does quite well in representing the observed CO2ff in 15 min averaged surface flask samples and in ~ one week integrated CO2ff averages from grass samples. In this pilot study, we found that using grass samples, the modeled and observed CO2ff emissions averaged over one week agreed to within 30%. The results imply that greater verification accuracy may be achieved by including more detailed meteorological observations and refining 14C sampling strategies.

Balsam-Pear-Skin-Like Porous Polyacrylonitrile Nanofibrous Membranes Grafted with Polyethyleneimine for Postcombustion CO2 Capture.

PubMed

Zhang, Yufei; Guan, Jiming; Wang, Xianfeng; Yu, Jianyong; Ding, Bin

2017-11-22

Amine-containing sorbents have been extensively studied for postcombustion carbon dioxide (CO 2 ) capture because of their ability to chemisorb CO 2 from the flue gas. However, most sorbents are in the form of powders currently, which is not the ideal configuration for the flue gas separation because of the fragile nature and poor mechanical properties, resulting in blocking of the flow pipes and difficult recycling. Herein, we present a novel approach for the facile fabrication of flexible, robust, and polyethyleneimine-grafted (PEI-grafted) hydrolyzed porous PAN nanofibrous membranes (HPPAN-PEI NFMs) through the combination of electrospinning, pore-forming process, hydrolysis reaction, and the subsequent grafting technique. Excitingly, we find that all the resultant porous PAN (PPAN) fibers exhibit a balsam-pear-skin-like porous structure due to the selective removal of poly(vinylpyrrolidone) (PVP) from PAN/PVP fibers by water extraction. Significantly, the HPPAN-PEI NFMs retain their mesoporosity, as well as exhibit good thermal stability and prominent tensile strength (11.1 MPa) after grafting, guaranteeing their application in CO 2 trapping from the flue gas. When exposed to CO 2 at 40 °C, the HPPAN-PEI NFMs show an enhanced CO 2 adsorption capacity of 1.23 mmol g -1 (based on the overall quantity of the sample) or 6.15 mmol g -1 (based on the quantity of grafted PEI). Moreover, the developed HPPAN-PEI NFMs display significantly selective capture for CO 2 over N 2 and excellent recyclability. The CO 2 capacity retains 92% of the initial value after 20 adsorption-desorption cycle tests, indicating that the resultant HPPAN-PEI NFMs have good long-term stability. This work paves the way for fabricating NFM-based solid adsorption materials endowed with a porous structure applied to efficient postcombustion CO 2 capture.

Linking CO 2 Sorption Performance to Polymer Morphology in Aminopolymer/Silica Composites through Neutron Scattering

DOE PAGES

Holewinski, Adam; Sakwa-Novak, Miles A.; Jones, Christopher W.

2015-08-26

Composites of poly(ethylenimine) (PEI) and mesoporous silica are effective, reversible adsorbents for CO 2, both from flue gas and in direct air-capture applications. The morphology of the PEI within the silica can strongly impact the overall carbon capture efficiency and rate of saturation. Here, we directly probe the spatial distribution of the supported polymer through small-angle neutron scattering (SANS). Combined with textural characterization from physisorption analysis, the data indicate that PEI first forms a thin conformal coating on the pore walls, but all additional polymer aggregates into plug(s) that grow along the pore axis. This model is consistent with observedmore » trends in amine-efficiency (CO 2/N binding ratio) and pore size distributions, and points to a trade-off between achieving high chemical accessibility of the amine binding sites, which are inaccessible when they strongly interact with the silica, and high accessibility for mass transport, which can be hampered by diffusion through PEI plugs. In conclusion, we illustrate this design principle by demonstrating higher CO 2 capacity and uptake rate for PEI supported in a hydrophobically modified silica, which exhibits repulsive interactions with the PEI, freeing up binding sites.« less

NRG CO 2NCEPT - Confirmation Of Novel Cost-effective Emerging Post-combustion Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stevenson, Matthew; Armpriester, Anthony

Under DOE's solicitation DE-FOA-0001190, NRG and Inventys conceptualized a Large-Scale pilot (>10MWe) post-combustion CO 2 capture project using Inventys' VeloxoThermTM carbon capture technology. The technology is comprised of an intensified thermal swing adsorption (TSA) process that uses a patented architecture of structured adsorbent and a novel process design and embodiment to capture CO 2 from industrial flue gas streams. The result of this work concluded that the retrofit of this technology is economically and technically viable, but that the sorbent material selected for the program would need improving to meet the techno-economic performance requirements of the solicitation.

The thiocyanate anion is a primary driver of carbon dioxide capture by ionic liquids

NASA Astrophysics Data System (ADS)

Chaban, Vitaly

2015-01-01

Carbon dioxide, CO2, capture by room-temperature ionic liquids (RTILs) is a vivid research area featuring both accomplishments and frustrations. This work employs the PM7-MD method to simulate adsorption of CO2 by 1,3-dimethylimidazolium thiocyanate at 300 K. The obtained result evidences that the thiocyanate anion plays a key role in gas capture, whereas the impact of the 1,3-dimethylimidazolium cation is mediocre. Decomposition of the computed wave function on the individual molecular orbitals confirms that CO2-SCN binding extends beyond just expected electrostatic interactions in the ion-molecular system and involves partial sharing of valence orbitals.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tande, Brian; Seames, Wayne; Benson, Steve

The objective of this project was to evaluate the use of composite polymer membranes and porous membrane contactors to regenerate physical and chemical solvents for capture of carbon dioxide (CO 2) from synthesis gas or flue gas, with the goal of improving the energy efficiency of carbon capture. Both a chemical solvent (typical for a post-combustion capture of CO 2 from flue gas) and a physical solvent (typical for pre- combustion capture of CO 2 from syngas) were evaluated using two bench-scale test systems constructed for this project. For chemical solvents, polytetrafluoroethylene and polypropylene membranes were found to be ablemore » to strip CO 2 from a monoethanolamine (MEA) solution with high selectivity without significant degradation of the material. As expected, the regeneration temperature was the most significant parameter affecting the CO 2 flux through the membrane. Pore size was also found to be important, as pores larger than 5 microns lead to excessive pore wetting. For physical solvents, polydimethyl-siloxane (PDMS)-based membranes were found to have a higher CO 2 permeability than polyvinylalcohol (PVOH) based membranes, while also minimizing solvent loss. Overall, however, the recovery of CO 2 in these systems is low – less than 2% for both chemical and physical solvents – primarily due to the small surface area of the membrane test apparatus. To obtain the higher regeneration rates needed for this application, a much larger surface area would be needed. Further experiments using, for example, a hollow fiber membrane module could determine if this process could be commercially viable.« less

Pilot-Scale Silicone Process for Low-Cost Carbon Dioxide Capture Preliminary Techno-Economic Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Surinder; Spiry, Irina; Wood, Benjamin

This report presents system and economic analysis for a carbon-capture unit which uses an aminosilicone-based solvent for CO{sub 2} capture in a pulverized coal (PC) boiler. The aminosilicone solvent is a 60/40 wt/wt mixture of 3-aminopropyl end-capped polydimethylsiloxane (GAP-1m) with tri-ethylene glycol (TEG) as a co-solvent. For comparison purposes, the report also shows results for a carbon-capture unit based on a conventional approach using mono-ethanol amine (MEA). The first year removal cost of CO{sub 2} for the aminosilicone-based carbon-capture process ismore » $46.04/ton of CO2 as compared to $$60.25/ton of CO{sub 2} when MEA is used. The aminosilicone-based process has <77% of the CAPEX of a system using MEA solvent. The lower CAPEX is due to several factors, including the higher working capacity of the aminosilicone solvent compared the MEA, which reduces the solvent flow rate required, reducing equipment sizes. If it is determined that carbon steel can be used in the rich-lean heat exchanger in the carbon capture unit, the first year removal cost of CO{sub 2} decreases to $$44.12/ton. The aminosilicone-based solvent has a higher thermal stability than MEA, allowing desorption to be conducted at higher temperatures and pressures, decreasing the number of compressor stages needed. The aminosilicone-based solvent also has a lower vapor pressure, allowing the desorption to be conducted in a continuous-stirred tank reactor versus a more expensive packed column. The aminosilicone-based solvent has a lower heat capacity, which decreases the heat load on the desorber. In summary, the amino-silicone solvent has significant advantages over conventional systems using MEA.« less

Holey graphene frameworks for highly selective post-combustion carbon capture

PubMed Central

Chowdhury, Shamik; Balasubramanian, Rajasekhar

2016-01-01

Atmospheric CO2 concentrations continue to rise rapidly in response to increased combustion of fossil fuels, contributing to global climate change. In order to mitigate the effects of global warming, development of new materials for cost-effective and energy-efficient CO2 capture is critically important. Graphene-based porous materials are an emerging class of solid adsorbents for selectively removing CO2 from flue gases. Herein, we report a simple and scalable approach to produce three-dimensional holey graphene frameworks with tunable porosity and pore geometry, and demonstrate their application as high-performance CO2 adsorbents. These holey graphene macrostructures exhibit a significantly improved specific surface area and pore volume compared to their pristine counterparts, and can be effectively used in post-combustion CO2 adsorption systems because of their intrinsic hydrophobicity together with good gravimetric storage capacities, rapid removal capabilities, superior cycling stabilities, and moderate initial isosteric heats. In addition, an exceptionally high CO2 over N2 selectivity can be achieved under conditions relevant to capture from the dry exhaust gas stream of a coal burning power plant, suggesting the possibility of recovering highly pure CO2 for long-term sequestration and/or utilization for downstream applications. PMID:26879393

Holey graphene frameworks for highly selective post-combustion carbon capture.

PubMed

Chowdhury, Shamik; Balasubramanian, Rajasekhar

2016-02-16

Atmospheric CO2 concentrations continue to rise rapidly in response to increased combustion of fossil fuels, contributing to global climate change. In order to mitigate the effects of global warming, development of new materials for cost-effective and energy-efficient CO2 capture is critically important. Graphene-based porous materials are an emerging class of solid adsorbents for selectively removing CO2 from flue gases. Herein, we report a simple and scalable approach to produce three-dimensional holey graphene frameworks with tunable porosity and pore geometry, and demonstrate their application as high-performance CO2 adsorbents. These holey graphene macrostructures exhibit a significantly improved specific surface area and pore volume compared to their pristine counterparts, and can be effectively used in post-combustion CO2 adsorption systems because of their intrinsic hydrophobicity together with good gravimetric storage capacities, rapid removal capabilities, superior cycling stabilities, and moderate initial isosteric heats. In addition, an exceptionally high CO2 over N2 selectivity can be achieved under conditions relevant to capture from the dry exhaust gas stream of a coal burning power plant, suggesting the possibility of recovering highly pure CO2 for long-term sequestration and/or utilization for downstream applications.

Holey graphene frameworks for highly selective post-combustion carbon capture

NASA Astrophysics Data System (ADS)

Chowdhury, Shamik; Balasubramanian, Rajasekhar

2016-02-01

Atmospheric CO2 concentrations continue to rise rapidly in response to increased combustion of fossil fuels, contributing to global climate change. In order to mitigate the effects of global warming, development of new materials for cost-effective and energy-efficient CO2 capture is critically important. Graphene-based porous materials are an emerging class of solid adsorbents for selectively removing CO2 from flue gases. Herein, we report a simple and scalable approach to produce three-dimensional holey graphene frameworks with tunable porosity and pore geometry, and demonstrate their application as high-performance CO2 adsorbents. These holey graphene macrostructures exhibit a significantly improved specific surface area and pore volume compared to their pristine counterparts, and can be effectively used in post-combustion CO2 adsorption systems because of their intrinsic hydrophobicity together with good gravimetric storage capacities, rapid removal capabilities, superior cycling stabilities, and moderate initial isosteric heats. In addition, an exceptionally high CO2 over N2 selectivity can be achieved under conditions relevant to capture from the dry exhaust gas stream of a coal burning power plant, suggesting the possibility of recovering highly pure CO2 for long-term sequestration and/or utilization for downstream applications.

Process for CO.sub.2 capture using a regenerable magnesium hydroxide sorbent

DOEpatents

Siriwardane, Ranjani V; Stevens, Jr., Robert W

2013-06-25

A process for CO.sub.2 separation using a regenerable Mg(OH).sub.2 sorbent. The process absorbs CO.sub.2 through the formation of MgCO.sub.3 and releases water product H.sub.2O. The MgCO.sub.3 is partially regenerated through direct contact with steam, which acts to heat the magnesium carbonate to a higher temperature, provide heat duty required to decompose the magnesium carbonate to yield MgO and CO.sub.2, provide an H.sub.2O environment over the magnesium carbonate thereby shifting the equilibrium and increasing the potential for CO.sub.2 desorption, and supply H.sub.2O for rehydroxylation of a portion of the MgO. The mixture is polished in the absence of CO.sub.2 using water product H.sub.2O produced during the CO.sub.2 absorption to maintain sorbent capture capacity. The sorbent now comprised substantially of Mg(OH).sub.2 is then available for further CO.sub.2 absorption duty in a cyclic process.

Are there interactive effects of physiological and radiative forcing produced by increased CO2 concentration on changes of land hydrological cycle?

NASA Astrophysics Data System (ADS)

Peng, Jing; Dan, Li; Dong, Wenjie

2014-01-01

Three coupled climate-carbon cycle models including CESM (Community Earth System Model), CanEsm (the Canadian Centre for Climate Modelling and Analysis Earth System Model) and BCC (Beijing Climate Center Climate System Model) were used to estimate whether changes in land hydrological cycle responded to the interactive effects of CO2-physiological forcing and CO2-radiative forcing. No signs could be indicated that the interactive effects of CO2-physiological forcing and CO2-radiative forcing on the hydrological variables (e.g. precipitation, evapotranspiration and runoff) were detected at global and regional scales. For each model, increases in precipitation, evapotranspiration and runoff (e.g. 0.37, 0.18 and 0.25 mm/year2) were simulated in response to CO2-radiative forcing (experiment M3). Decreases in precipitation and evapotranspiration (about - 0.02 and - 0.09 mm/year2) were captured if the CO2 physiological effect was only accounted for (experiment M2). In this experiment, a reverse sign in runoff (the increase of 0.08 mm/year2) in contrast to M3 is presented. All models simulated the same signs across Eastern Asia in response to the CO2 physiological forcing and radiative forcing: increases in precipitation and evapotranspiration only considering greenhouse effect; reductions in precipitation and evapotranspiration in response to CO2-physiological effect; and enhanced trends in runoff from all experiments. However, there was still a large uncertainty on the magnitude of the effect of transpiration on runoff (decreased transpiration accounting for 8% to 250% of the increased runoff) from the three models. Two models (CanEsm and BCC) attributed most of the increase in runoff to the decrease in transpiration if the CO2-physiological effect was only accounted for, whereas CESM exhibited that the decrease in transpiration could not totally explain the increase in runoff. The attribution of the CO2-physiological forcing to changes in stomatal conductance versus changes in vegetation structure (e.g. increased Leaf Area Index) is an issue to discuss, and among the three models, no agreement appeared.

Energy and economic analysis of the carbon dioxide capture installation with the use of monoethanolamine and ammonia

NASA Astrophysics Data System (ADS)

Bochon, Krzysztof; Chmielniak, Tadeusz

2015-03-01

In the study an accurate energy and economic analysis of the carbon capture installation was carried out. Chemical absorption with the use of monoethanolamine (MEA) and ammonia was adopted as the technology of carbon dioxide (CO2) capture from flue gases. The energy analysis was performed using a commercial software package to analyze the chemical processes. In the case of MEA, the demand for regeneration heat was about 3.5 MJ/kg of CO2, whereas for ammonia it totalled 2 MJ/kg CO2. The economic analysis was based on the net present value (NPV) method. The limit price for CO2 emissions allowances at which the investment project becomes profitable (NPV = 0) was more than 160 PLN/Mg for MEA and less than 150 PLN/Mg for ammonia. A sensitivity analysis was also carried out to determine the limit price of CO2 emissions allowances depending on electricity generation costs at different values of investment expenditures.

Doping of alkali, alkaline-earth, and transition metals in covalent-organic frameworks for enhancing CO2 capture by first-principles calculations and molecular simulations.

PubMed

Lan, Jianhui; Cao, Dapeng; Wang, Wenchuan; Smit, Berend

2010-07-27

We use the multiscale simulation approach, which combines the first-principles calculations and grand canonical Monte Carlo simulations, to comprehensively study the doping of a series of alkali (Li, Na, and K), alkaline-earth (Be, Mg, and Ca), and transition (Sc and Ti) metals in nanoporous covalent organic frameworks (COFs), and the effects of the doped metals on CO2 capture. The results indicate that, among all the metals studied, Li, Sc, and Ti can bind with COFs stably, while Be, Mg, and Ca cannot, because the binding of Be, Mg, and Ca with COFs is very weak. Furthermore, Li, Sc, and Ti can improve the uptakes of CO2 in COFs significantly. However, the binding energy of a CO2 molecule with Sc and Ti exceeds the lower limit of chemisorptions and, thus, suffers from the difficulty of desorption. By the comparative studies above, it is found that Li is the best surface modifier of COFs for CO2 capture among all the metals studied. Therefore, we further investigate the uptakes of CO2 in the Li-doped COFs. Our simulation results show that at 298 K and 1 bar, the excess CO2 uptakes of the Li-doped COF-102 and COF-105 reach 409 and 344 mg/g, which are about eight and four times those in the nondoped ones, respectively. As the pressure increases to 40 bar, the CO2 uptakes of the Li-doped COF-102 and COF-105 reach 1349 and 2266 mg/g at 298 K, respectively, which are among the reported highest scores to date. In summary, doping of metals in porous COFs provides an efficient approach for enhancing CO2 capture.

Anion-activated, thermoreversible gelation system for the capture, release, and visual monitoring of CO2

PubMed Central

Zhang, Xin; Lee, Songyi; Liu, Yifan; Lee, Minji; Yin, Jun; Sessler, Jonathan L.; Yoon, Juyoung

2014-01-01

Carbon dioxide (CO2) is an important green house gas. This is providing an incentive to develop new strategies to detect and capture CO2. Achieving both functions within a single molecular system represents an unmet challenge in terms of molecular design and could translate into enhanced ease of use. Here, we report an anion-activated chemosensor system, NAP-chol 1, that permits dissolved CO2 to be detected in organic media via simple color changes or through ratiometric differences in fluorescence intensity. NAP-chol 1 also acts as a super gelator for DMSO. The resulting gel is transformed into a homogeneous solution upon exposure to fluoride anions. Bubbling with CO2 regenerates the gel. Subsequent flushing with N2 or heating serves to release the CO2 and reform the sol form. This series of transformations is reversible and can be followed by easy-to-discern color changes. Thus, NAP-chol 1 allows for the capture and release of CO2 gas while acting as a three mode sensing system. In particular, it permits CO2 to be detected through reversible sol-gel transitions, simple changes in color, or ratiometric monitoring of the differences in the fluorescence features. PMID:24699626

Comparative Assessment of Gasification Based Coal Power Plants with Various CO2 Capture Technologies Producing Electricity and Hydrogen

PubMed Central

2014-01-01

Seven different types of gasification-based coal conversion processes for producing mainly electricity and in some cases hydrogen (H2), with and without carbon dioxide (CO2) capture, were compared on a consistent basis through simulation studies. The flowsheet for each process was developed in a chemical process simulation tool “Aspen Plus”. The pressure swing adsorption (PSA), physical absorption (Selexol), and chemical looping combustion (CLC) technologies were separately analyzed for processes with CO2 capture. The performances of the above three capture technologies were compared with respect to energetic and exergetic efficiencies, and the level of CO2 emission. The effect of air separation unit (ASU) and gas turbine (GT) integration on the power output of all the CO2 capture cases is assessed. Sensitivity analysis was carried out for the CLC process (electricity-only case) to examine the effect of temperature and water-cooling of the air reactor on the overall efficiency of the process. The results show that, when only electricity production in considered, the case using CLC technology has an electrical efficiency 1.3% and 2.3% higher than the PSA and Selexol based cases, respectively. The CLC based process achieves an overall CO2 capture efficiency of 99.9% in contrast to 89.9% for PSA and 93.5% for Selexol based processes. The overall efficiency of the CLC case for combined electricity and H2 production is marginally higher (by 0.3%) than Selexol and lower (by 0.6%) than PSA cases. The integration between the ASU and GT units benefits all three technologies in terms of electrical efficiency. Furthermore, our results suggest that it is favorable to operate the air reactor of the CLC process at higher temperatures with excess air supply in order to achieve higher power efficiency. PMID:24578590

Comparative Assessment of Gasification Based Coal Power Plants with Various CO2 Capture Technologies Producing Electricity and Hydrogen.

PubMed

Mukherjee, Sanjay; Kumar, Prashant; Hosseini, Ali; Yang, Aidong; Fennell, Paul

2014-02-20

Seven different types of gasification-based coal conversion processes for producing mainly electricity and in some cases hydrogen (H 2 ), with and without carbon dioxide (CO 2 ) capture, were compared on a consistent basis through simulation studies. The flowsheet for each process was developed in a chemical process simulation tool "Aspen Plus". The pressure swing adsorption (PSA), physical absorption (Selexol), and chemical looping combustion (CLC) technologies were separately analyzed for processes with CO 2 capture. The performances of the above three capture technologies were compared with respect to energetic and exergetic efficiencies, and the level of CO 2 emission. The effect of air separation unit (ASU) and gas turbine (GT) integration on the power output of all the CO 2 capture cases is assessed. Sensitivity analysis was carried out for the CLC process (electricity-only case) to examine the effect of temperature and water-cooling of the air reactor on the overall efficiency of the process. The results show that, when only electricity production in considered, the case using CLC technology has an electrical efficiency 1.3% and 2.3% higher than the PSA and Selexol based cases, respectively. The CLC based process achieves an overall CO 2 capture efficiency of 99.9% in contrast to 89.9% for PSA and 93.5% for Selexol based processes. The overall efficiency of the CLC case for combined electricity and H 2 production is marginally higher (by 0.3%) than Selexol and lower (by 0.6%) than PSA cases. The integration between the ASU and GT units benefits all three technologies in terms of electrical efficiency. Furthermore, our results suggest that it is favorable to operate the air reactor of the CLC process at higher temperatures with excess air supply in order to achieve higher power efficiency.

Mathematical modeling and experimental breakthrough curves of carbon dioxide adsorption on metal organic framework CPM-5.

PubMed

Sabouni, Rana; Kazemian, Hossein; Rohani, Sohrab

2013-08-20

It is essential to capture carbon dioxide from flue gas because it is considered one of the main causes of global warming. Several materials and different methods have been reported for CO2 capturing including adsorption onto zeolites and porous membranes, as well as absorption in amine solutions. All such methods require high energy input and high cost. A new class of porous materials called Metal Organic Frameworks (MOFs) exhibited excellent performance in extracting carbon dioxide from a gas mixture. In this study, the breakthrough curves for the adsorption of carbon dioxide on CPM-5 (crystalline porous materials) were obtained experimentally and theoretically using a laboratory-scale fixed-bed column at different experimental conditions such as feed flow rate, adsorption temperature, and feed concentration. It was found that the CPM-5 has a dynamic CO2 adsorption capacity of 11.9 wt % (2.7 mmol/g) (corresponding to 8 mL/min, 298 K, and 25% v/v CO2). The tested CPM-5 showed an outstanding adsorption equilibrium capacity (e.g., 2.3 mmol/g (10.2 wt %) at 298 K) compared to other adsorbents, which can be considered as an attractive adsorbent for separation of CO2 from flue gas.

Beyond the standard two-film theory: Computational fluid dynamics simulations for carbon dioxide capture in a wetted wall column

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Xu, Zhijie; Lai, Canhai

The standard two-film theory (STFT) is a diffusion-based mechanism that can be used to describe gas mass transfer across liquid film. Fundamental assumptions of the STFT impose serious limitations on its ability to predict mass transfer coefficients. To better understand gas absorption across liquid film in practical situations, a multiphase computational fluid dynamics (CFD) model fully equipped with mass transport and chemistry capabilities has been developed for solvent-based carbon dioxide (CO 2) capture to predict the CO 2 mass transfer coefficient in a wetted wall column. The hydrodynamics is modeled using a volume of fluid method, and the diffusive andmore » reactive mass transfer between the two phases is modeled by adopting a one-fluid formulation. We demonstrate that the proposed CFD model can naturally account for the influence of many important factors on the overall mass transfer that cannot be quantitatively explained by the STFT, such as the local variation in fluid velocities and properties, flow instabilities, and complex geometries. The CFD model also can predict the local mass transfer coefficient variation along the column height, which the STFT typically does not consider.« less

Beyond the standard two-film theory: Computational fluid dynamics simulations for carbon dioxide capture in a wetted wall column

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Xu, Zhijie; Lai, Canhai

The standard two-film theory (STFT) is a diffusion-based mechanism that can be used to describe gas mass transfer across liquid film. Fundamental assumptions of the STFT impose serious limitations on its ability to predict mass transfer coefficients. To better understand gas absorption across liquid film in practical situations, a multiphase computational fluid dynamics (CFD) model fully equipped with mass transport and chemistry capabilities has been developed for solvent-based carbon dioxide (CO2) capture to predict the CO2 mass transfer coefficient in a wetted wall column. The hydrodynamics is modeled using a volume of fluid method, and the diffusive and reactive massmore » transfer between the two phases is modeled by adopting a one-fluid formulation. We demonstrate that the proposed CFD model can naturally account for the influence of many important factors on the overall mass transfer that cannot be quantitatively explained by the STFT, such as the local variation in fluid velocities and properties, flow instabilities, and complex geometries. The CFD model also can predict the local mass transfer coefficient variation along the column height, which the STFT typically does not consider.« less

Beyond the standard two-film theory: Computational fluid dynamics simulations for carbon dioxide capture in a wetted wall column

DOE PAGES

Wang, Chao; Xu, Zhijie; Lai, Canhai; ...

2018-03-27

The standard two-film theory (STFT) is a diffusion-based mechanism that can be used to describe gas mass transfer across liquid film. Fundamental assumptions of the STFT impose serious limitations on its ability to predict mass transfer coefficients. To better understand gas absorption across liquid film in practical situations, a multiphase computational fluid dynamics (CFD) model fully equipped with mass transport and chemistry capabilities has been developed for solvent-based carbon dioxide (CO 2) capture to predict the CO 2 mass transfer coefficient in a wetted wall column. The hydrodynamics is modeled using a volume of fluid method, and the diffusive andmore » reactive mass transfer between the two phases is modeled by adopting a one-fluid formulation. We demonstrate that the proposed CFD model can naturally account for the influence of many important factors on the overall mass transfer that cannot be quantitatively explained by the STFT, such as the local variation in fluid velocities and properties, flow instabilities, and complex geometries. The CFD model also can predict the local mass transfer coefficient variation along the column height, which the STFT typically does not consider.« less

Study of CO2 bubble dynamics in seawater from QICS field Experiment

NASA Astrophysics Data System (ADS)

Chen, B.; Dewar, M.; Sellami, N.; Stahl, H.; Blackford, J.

2011-12-01

One of the concerns of employing CCS at engineering scale is the risk of leakage of storage CO2 on the environment and especially on the marine life. QICS, a scientific research project was launched with an aim to study the effects of a potential leak from a CCS system on the UK marine environment [1]. The project involves the injection of CO2 from a shore-based lab into shallow marine sediments. One of the main objectives of the project is to generate experimental data to be compared with the developed physical models. The results of the models are vital for the biogeochemical and ecological models in order to predict the impact of a CO2 leak in a variety of situations. For the evaluation of the fate of the CO2 bubbles into the surrounding seawater, the physical model requires two key parameters to be used as input which are: (i) a correlation of the drag coefficient as function of the CO2 bubble Reynolds number and (ii) the CO2 bubble size distribution. By precisely measuring the CO2 bubble size and rising speed, these two parameters can be established. For this purpose, the dynamical characteristics of the rising CO2 bubbles in Scottish seawater were investigated experimentally within the QICS project. Observations of the CO2 bubbles plume rising freely in the in seawater column were captured by video survey using a ruler positioned at the leakage pockmark as dimension reference. This observation made it possible, for the first time, to discuss the dynamics of the CO2 bubbles released in seawater. [1] QICS, QICS: Quantifying and Monitoring Potential Ecosystem Impacts of Geological Carbon Storage. (Accessed 15.07.13), http://www.bgs.ac.uk/qics/home.html

Study of CO2 bubble dynamics in seawater from QICS field Experiment

NASA Astrophysics Data System (ADS)

Chen, B.; Dewar, M.; Sellami, N.; Stahl, H.; Blackford, J.

2013-12-01

One of the concerns of employing CCS at engineering scale is the risk of leakage of storage CO2 on the environment and especially on the marine life. QICS, a scientific research project was launched with an aim to study the effects of a potential leak from a CCS system on the UK marine environment [1]. The project involves the injection of CO2 from a shore-based lab into shallow marine sediments. One of the main objectives of the project is to generate experimental data to be compared with the developed physical models. The results of the models are vital for the biogeochemical and ecological models in order to predict the impact of a CO2 leak in a variety of situations. For the evaluation of the fate of the CO2 bubbles into the surrounding seawater, the physical model requires two key parameters to be used as input which are: (i) a correlation of the drag coefficient as function of the CO2 bubble Reynolds number and (ii) the CO2 bubble size distribution. By precisely measuring the CO2 bubble size and rising speed, these two parameters can be established. For this purpose, the dynamical characteristics of the rising CO2 bubbles in Scottish seawater were investigated experimentally within the QICS project. Observations of the CO2 bubbles plume rising freely in the in seawater column were captured by video survey using a ruler positioned at the leakage pockmark as dimension reference. This observation made it possible, for the first time, to discuss the dynamics of the CO2 bubbles released in seawater. [1] QICS, QICS: Quantifying and Monitoring Potential Ecosystem Impacts of Geological Carbon Storage. (Accessed 15.07.13), http://www.bgs.ac.uk/qics/home.html

Two-dimensional nitrides as highly efficient potential candidates for CO2 capture and activation.

PubMed

Morales-Salvador, Raul; Morales-García, Ángel; Viñes, Francesc; Illas, Francesc

2018-06-13

The performance of novel two-dimensional nitrides in carbon capture and storage (CCS) is analyzed for a broad range of pressures and temperatures. Employing an integrated theoretical framework where CO2 adsorption/desorption rates on the M2N (M = Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W) surfaces are derived from transition state theory and density functional theory based calculations, the present theoretical simulations consistently predict that, depending on the particular composition, CO2 can be strongly adsorbed and even activated at temperatures above 1000 K. For practical purposes, Ti2N, Zr2N, Hf2N, V2N, Nb2N, and Ta2N are predicted as the best suited materials for CO2 activation. Moreover, the estimated CO2 uptake of 2.32-7.96 mol CO2 kg-1 reinforces the potential of these materials for CO2 abatement.

Energy requirements for CO2 capture from ambient air (DAC) competitive with capture from flue-gas (PCC)

NASA Astrophysics Data System (ADS)

Meinrenken, Christoph

2015-03-01

Capture of CO2, whether from a flue gas source (PCC) or from distributed sources via ambient air (DAC), is a key enabling technology to provide carbon for sustainable synthetic energy carriers such as solar fuels. Based on thermodynamic minimum considerations, DAC is often expected to require about 3 times more energy (per ton CO2 captured) than PCC because CO2 in ambient air is more dilute. Here, we calculate the energy required for a humidity swing-based DAC installation that uses an anionic exchange resin as sorbent. The calculation uses recently measured equilibrium CO2 loadings of the sorbent as function of partial CO2 pressure, temperature, and humidity. We calculate the installation's electricity consumption to be about 45 kJ per mole of pure CO2 at 1 bar (scenario-dependent). Furthermore, we estimate the amount of heat provided by ambient air and thus provide context of the overall energy and entropy balance and thermodynamic minimum views. The electricity consumption is competitive with typical parasitic loads of PCC-equipped coal-fired power plants (40-50 kJ per mole at same pressure) and significantly lower than predicted for other DAC installations such as Na(OH) sorbent-based systems. Our analyses elucidate why DAC is not always more energy-intensive that PCC, thus alleviating often cited concerns of significant cost impediments. Financial support by ABB for research presented herein is gratefully acknowledged.

Ionic-Liquid-Based CO2 Capture Systems: Structure, Interaction and Process.

PubMed

Zeng, Shaojuan; Zhang, Xiangping; Bai, Lu; Zhang, Xiaochun; Wang, Hui; Wang, Jianji; Bao, Di; Li, Mengdie; Liu, Xinyan; Zhang, Suojiang

2017-07-26

The inherent structure tunability, good affinity with CO 2 , and nonvolatility of ionic liquids (ILs) drive their exploration and exploitation in CO 2 separation field, and has attracted remarkable interest from both industries and academia. The aim of this Review is to give a detailed overview on the recent advances on IL-based materials, including pure ILs, IL-based solvents, and IL-based membranes for CO 2 capture and separation from the viewpoint of molecule to engineering. The effects of anions, cations and functional groups on CO 2 solubility and selectivity of ILs, as well as the studies on degradability of ILs are reviewed, and the recent developments on functionalized ILs, IL-based solvents, and IL-based membranes are also discussed. CO 2 separation mechanism with IL-based solvents and IL-based membranes are explained by combining molecular simulation and experimental characterization. Taking into consideration of the applications and industrialization, the recent achievements and developments on the transport properties of IL fluids and the process design of IL-based processes are highlighted. Finally, the future research challenges and perspectives of the commercialization of CO 2 capture and separation with IL-based materials are posed.

Responses to atmospheric CO2 concentrations in crop simulation models: a review of current simple and semicomplex representations and options for model development.

PubMed

Vanuytrecht, Eline; Thorburn, Peter J

2017-05-01

Elevated atmospheric CO 2 concentrations ([CO 2 ]) cause direct changes in crop physiological processes (e.g. photosynthesis and stomatal conductance). To represent these CO 2 responses, commonly used crop simulation models have been amended, using simple and semicomplex representations of the processes involved. Yet, there is no standard approach to and often poor documentation of these developments. This study used a bottom-up approach (starting with the APSIM framework as case study) to evaluate modelled responses in a consortium of commonly used crop models and illuminate whether variation in responses reflects true uncertainty in our understanding compared to arbitrary choices of model developers. Diversity in simulated CO 2 responses and limited validation were common among models, both within the APSIM framework and more generally. Whereas production responses show some consistency up to moderately high [CO 2 ] (around 700 ppm), transpiration and stomatal responses vary more widely in nature and magnitude (e.g. a decrease in stomatal conductance varying between 35% and 90% among models was found for [CO 2 ] doubling to 700 ppm). Most notably, nitrogen responses were found to be included in few crop models despite being commonly observed and critical for the simulation of photosynthetic acclimation, crop nutritional quality and carbon allocation. We suggest harmonization and consideration of more mechanistic concepts in particular subroutines, for example, for the simulation of N dynamics, as a way to improve our predictive understanding of CO 2 responses and capture secondary processes. Intercomparison studies could assist in this aim, provided that they go beyond simple output comparison and explicitly identify the representations and assumptions that are causal for intermodel differences. Additionally, validation and proper documentation of the representation of CO 2 responses within models should be prioritized. © 2017 John Wiley & Sons Ltd.

CO2 Capture and Storage in Coal Gasification Projects

NASA Astrophysics Data System (ADS)

Rao, Anand B.; Phadke, Pranav C.

2017-07-01

In response to the global climate change problem, the world community today is in search for an effective means of carbon mitigation. India is a major developing economy and the economic growth is driven by ever-increasing consumption of energy. Coal is the only fossil fuel that is available in abundance in India and contributes to the major share of the total primary energy supply (TPES) in the country. Owing to the large unmet demand for affordable energy, primarily driven by the need for infrastructure development and increasing incomes and aspirations of people, as well as the energy security concerns, India is expected to have continued dependence on coal. Coal is not only the backbone of the electric power generation, but many major industries like cement, iron and steel, bricks, fertilizers also consume large quantities of coal. India has very low carbon emissions (˜ 1.5 tCO2 per capita) as compared to the world average (4.7 tCO2 per capita) and the developed world (11.2 tCO2 per capita). Although the aggregate emissions of the country are increasing with the rising population and fossil energy use, India has a very little contribution to the historical GHG accumulation in the atmosphere linked to the climate change problem. However, a large fraction of the Indian society is vulnerable to the impacts of climate change - due to its geographical location, large dependence on monsoon-based agriculture and limited technical, financial and institutional capacity. Today, India holds a large potential to offer cost-effective carbon mitigation to tackle the climate change problem. Carbon Capture and Storage (CCS) is the process of extraction of Carbon Dioxide (CO2) from industrial and energy related sources, transport to storage locations and long-term isolation from the atmosphere. It is a technology that has been developed in recent times and is considered as a bridging technology as we move towards carbon-neutral energy sources in response to the growing concerns about climate change problem. Carbon Capture and Storage (CCS) is being considered as a promising carbon mitigation technology, especially for large point sources such as coal power plants. Gasification of coal helps in better utilization of this resource offering multiple advantages such as pollution prevention, product flexibility (syngas and hydrogen) and higher efficiency (combined cycle). It also enables the capture of CO2 prior to the combustion, from the fuel gas mixture, at relatively lesser cost as compared to the post-combustion CO2 capture. CCS in gasification projects is considered as a promising technology for cost-effective carbon mitigation. Although many projects (power and non-power) have been announced internationally, very few large-scale projects have actually come up. This paper looks at the various aspects of CCS applications in gasification projects, including the technical feasibility and economic viability and discusses an Indian perspective. Impacts of including CCS in gasification projects (e.g. IGCC plants) have been assessed using a simulation tool. Integrated Environmental Control Model (IECM) - a modelling framework to simulate power plants - has been used to estimate the implications of adding CCS units in IGCC plants, on their performance and costs.

Industrial point source CO2 emission strength estimation with aircraft measurements and dispersion modelling.

PubMed

Carotenuto, Federico; Gualtieri, Giovanni; Miglietta, Franco; Riccio, Angelo; Toscano, Piero; Wohlfahrt, Georg; Gioli, Beniamino

2018-02-22

CO 2 remains the greenhouse gas that contributes most to anthropogenic global warming, and the evaluation of its emissions is of major interest to both research and regulatory purposes. Emission inventories generally provide quite reliable estimates of CO 2 emissions. However, because of intrinsic uncertainties associated with these estimates, it is of great importance to validate emission inventories against independent estimates. This paper describes an integrated approach combining aircraft measurements and a puff dispersion modelling framework by considering a CO 2 industrial point source, located in Biganos, France. CO 2 density measurements were obtained by applying the mass balance method, while CO 2 emission estimates were derived by implementing the CALMET/CALPUFF model chain. For the latter, three meteorological initializations were used: (i) WRF-modelled outputs initialized by ECMWF reanalyses; (ii) WRF-modelled outputs initialized by CFSR reanalyses and (iii) local in situ observations. Governmental inventorial data were used as reference for all applications. The strengths and weaknesses of the different approaches and how they affect emission estimation uncertainty were investigated. The mass balance based on aircraft measurements was quite succesful in capturing the point source emission strength (at worst with a 16% bias), while the accuracy of the dispersion modelling, markedly when using ECMWF initialization through the WRF model, was only slightly lower (estimation with an 18% bias). The analysis will help in highlighting some methodological best practices that can be used as guidelines for future experiments.

Intro to Carbon Sequestration

ScienceCinema

None

2017-12-09

NETL's Carbon Sequestration Program is helping to develop technologies to capture, purify, and store carbon dioxide (CO2) in order to reduce greenhouse gas emissions without adversely influencing energy use or hindering economic growth. Carbon sequestration technologies capture and store CO2 that would otherwise reside in the atmosphere for long periods of time.

Effect of CuO on the efficiency of sulfur capture of Ca-based compounds during coal combustion.

PubMed

Zheng, Li-Qing; Lu, Wen-Ying; Liu, Guo-Guang

2003-05-01

The efficiency of sulfur capture of CaO, Ca(OH)2 and CaCO3 as well as the effect of CuO on them were studied. Results showed that the efficiency of sulfur capture of Ca(OH)2 is the highest among these three compounds. When CuO was used with each of CaO, Ca(OH)2 and CaCO3 at the same time, the efficiency of all of them would rise, and that of Ca(OH)2 raise most. The efficiency of sulfur capture of Ca(OH)2 with CuO is 14.4% higher than that without CuO.

Flue-gas and direct-air capture of CO2 by porous metal–organic materials

PubMed Central

2017-01-01

Sequestration of CO2, either from gas mixtures or directly from air (direct air capture), is a technological goal important to large-scale industrial processes such as gas purification and the mitigation of carbon emissions. Previously, we investigated five porous materials, three porous metal–organic materials (MOMs), a benchmark inorganic material, Zeolite 13X and a chemisorbent, TEPA-SBA-15, for their ability to adsorb CO2 directly from air and from simulated flue-gas. In this contribution, a further 10 physisorbent materials that exhibit strong interactions with CO2 have been evaluated by temperature-programmed desorption for their potential utility in carbon capture applications: four hybrid ultramicroporous materials, SIFSIX-3-Cu, DICRO-3-Ni-i, SIFSIX-2-Cu-i and MOOFOUR-1-Ni; five microporous MOMs, DMOF-1, ZIF-8, MIL-101, UiO-66 and UiO-66-NH2; an ultramicroporous MOM, Ni-4-PyC. The performance of these MOMs was found to be negatively impacted by moisture. Overall, we demonstrate that the incorporation of strong electrostatics from inorganic moieties combined with ultramicropores offers improved CO2 capture performance from even moist gas mixtures but not enough to compete with chemisorbents. This article is part of the themed issue ‘Coordination polymers and metal–organic frameworks: materials by design’. PMID:27895255

Process modeling of an advanced NH₃ abatement and recycling technology in the ammonia-based CO₂ capture process.

PubMed

Li, Kangkang; Yu, Hai; Tade, Moses; Feron, Paul; Yu, Jingwen; Wang, Shujuan

2014-06-17

An advanced NH3 abatement and recycling process that makes great use of the waste heat in flue gas was proposed to solve the problems of ammonia slip, NH3 makeup, and flue gas cooling in the ammonia-based CO2 capture process. The rigorous rate-based model, RateFrac in Aspen Plus, was thermodynamically and kinetically validated by experimental data from open literature and CSIRO pilot trials at Munmorah Power Station, Australia, respectively. After a thorough sensitivity analysis and process improvement, the NH3 recycling efficiency reached as high as 99.87%, and the NH3 exhaust concentration was only 15.4 ppmv. Most importantly, the energy consumption of the NH3 abatement and recycling system was only 59.34 kJ/kg CO2 of electricity. The evaluation of mass balance and temperature steady shows that this NH3 recovery process was technically effective and feasible. This process therefore is a promising prospect toward industrial application.

Adaptation to high CO2 concentration in an optimal environment: radiation capture, canopy quantum yield and carbon use efficiency

NASA Technical Reports Server (NTRS)

Monje, O.; Bugbee, B.

1998-01-01

The effect of elevated [CO2] on wheat (Triticum aestivum L. Veery 10) productivity was examined by analysing radiation capture, canopy quantum yield, canopy carbon use efficiency, harvest index and daily C gain. Canopies were grown at either 330 or 1200 micromoles mol-1 [CO2] in controlled environments, where root and shoot C fluxes were monitored continuously from emergence to harvest. A rapidly circulating hydroponic solution supplied nutrients, water and root zone oxygen. At harvest, dry mass predicted from gas exchange data was 102.8 +/- 4.7% of the observed dry mass in six trials. Neither radiation capture efficiency nor carbon use efficiency were affected by elevated [CO2], but yield increased by 13% due to a sustained increase in canopy quantum yield. CO2 enrichment increased root mass, tiller number and seed mass. Harvest index and chlorophyll concentration were unchanged, but CO2 enrichment increased average life cycle net photosynthesis (13%, P < 0.05) and root respiration (24%, P < 0.05). These data indicate that plant communities adapt to CO2 enrichment through changes in C allocation. Elevated [CO2] increases sink strength in optimal environments, resulting in sustained increases in photosynthetic capacity, canopy quantum yield and daily C gain throughout the life cycle.

Micro-PIV measurements of multiphase flow of water and liquid CO2 in 2-D heterogeneous porous micromodels

NASA Astrophysics Data System (ADS)

Li, Yaofa; Kazemifar, Farzan; Blois, Gianluca; Christensen, Kenneth T.

2017-07-01

We present an experimental study of pore-scale flow dynamics of liquid CO2 and water in a two-dimensional heterogeneous porous micromodel, inspired by the structure of a reservoir rock, at reservoir-relevant conditions (80 bar, 21°C). The entire process of CO2 infiltration into a water-saturated micromodel was captured using fluorescence microscopy and the micro-PIV method, which together reveal complex fluid displacement patterns and abrupt changes in velocity. The CO2 front migrated through the resident water in an intermittent manner, forming dendritic structures, termed fingers, in directions along, normal to, and even opposing the bulk pressure gradient. Such characteristics indicate the dominance of capillary fingering through the micromodel. Velocity burst events, termed Haines jumps, were also captured in the heterogeneous micromodel, during which the local Reynolds number was estimated to be ˜21 in the CO2 phase, exceeding the range of validity of Darcy's law. Furthermore, these drainage events were observed to be cooperative (i.e., across multiple pores simultaneously), with the zone of influence of such events extending beyond tens of pores, confirming, in a quantitative manner, that Haines jumps are nonlocal phenomena. After CO2 completely breaks through the porous section, shear-induced circulations caused by flowing CO2 were also observed, in agreement with previous studies using a homogeneous porous micromodel. To our knowledge, this study is the first quantitative measurement that incorporates both reservoir-relevant conditions and rock-inspired heterogeneity, and thus will be useful for pore-scale model development and validation.

Parametric analysis of a novel cryogenic CO2 capture system based on Stirling coolers.

PubMed

Song, Chun Feng; Kitamura, Yutaka; Li, Shu Hong; Jiang, Wei Zhong

2012-11-20

CO(2) capture and storage (CCS) is an important alternative to control greenhouse gas (GHG) effects. In previous work, a novel desublimation CO(2) capture process has been exploited making use of three free piston Stirling coolers (namely, SC-1, SC-2, and SC-3, respectively). Based on the developed system, moisture and CO(2) in the flue gas can condense and desublimate in the prefreezing and main-freezing towers, respectively. Meanwhile, the storage column is chilled by SC-3 to preserve the frosted CO(2), and permanent gas (such as N(2)) passes through the system without phase change. The whole process can be implemented at atmospheric pressure and reduce the energy penalty (e.g., solvent regeneration and pressure drop) in other technologies. In this work, the influence of process parameters has been investigated in detail. The optimal conditions for the system are as follows: idle operating time is 240 min, flow rate is 5 L/min, vacuum degree of the interlayer is 2.2 × 10(3) Pa, and temperatures of SC-1, -2, and -3 are -30, -120, and -120 °C, respectively. Under these conditions, the energy consumption of the system is around 0.5 MJ(electrical)/kg CO(2) with above 90% CO(2) recovery.

Porous Ionic Polymers as a Robust and Efficient Platform for Capture and Chemical Fixation of Atmospheric CO2.

PubMed

Sun, Qi; Jin, Yingyin; Aguila, Briana; Meng, Xiangju; Ma, Shengqian; Xiao, Feng-Shou

2017-03-22

Direct use of atmospheric CO 2 as a C 1 source to synthesize high-value chemicals through environmentally benign processes is of great interest, yet challenging. Porous heterogeneous catalysts that are capable of simultaneously capturing and converting CO 2 are promising candidates for such applications. Herein, a family of organic ionic polymers with nanoporous structure, large surface area, strong affinity for CO 2 , and very high density of catalytic active sites (halide ions) was synthesized through the free-radical polymerization of vinylfunctionalized quaternary phosphonium salts. The resultant porous ionic polymers (PIPs) exhibit excellent activities in the cycloaddition of epoxides with atmospheric CO 2 , outperforming the corresponding soluble phosphonium salt analogues and ranking among the highest of known metal-free catalytic systems. The high CO 2 uptake capacity of the PIPs facilitates the enrichment of CO 2 molecules around the catalytic centers, thereby benefiting its conversion. We have demonstrated for the first time that atmospheric CO 2 can be directly converted to cyclic carbonates at room temperature using a heterogeneous catalytic system under metal-solvent free conditions. Moreover, the catalysts proved to be robust and fully recyclable, demonstrating promising potential for practical utilization for the chemical fixation of CO 2 . Our work thereby paves a way to the advance of PIPs as a new type of platform for capture and conversion of CO 2 . © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Calibration and Propagation of Uncertainty for Independence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, Troy Michael; Kress, Joel David; Bhat, Kabekode Ghanasham

This document reports on progress and methods for the calibration and uncertainty quantification of the Independence model developed at UT Austin. The Independence model is an advanced thermodynamic and process model framework for piperazine solutions as a high-performance CO 2 capture solvent. Progress is presented in the framework of the CCSI standard basic data model inference framework. Recent work has largely focused on the thermodynamic submodels of Independence.

Proper accounting for time increases crop-based biofuels' greenhouse gas deficit versus petroleum

NASA Astrophysics Data System (ADS)

O'Hare, M.; Plevin, R. J.; Martin, J. I.; Jones, A. D.; Kendall, A.; Hopson, E.

2009-04-01

The global warming intensities of crop-based biofuels and fossil fuels differ not only in amount but also in their discharge patterns over time. Early discharges, for example, from market-mediated land use change, will have created more global warming by any time in the future than later discharges, owing to the slow decay of atmospheric CO2. A spreadsheet model of this process, BTIME, captures this important time pattern effect using the Bern CO2 decay model to allow fuels to be compared for policy decisions on the basis of their real warming effects with a variety of user-supplied parameter values. The model also allows economic discounting of climate effects extended far into the future. Compared to approaches that simply sum greenhouse gas emissions over time, recognizing the physics of atmospheric CO2 decay significantly increases the deficit relative to fossil fuel of any biofuel causing land use change.

Complexes in the Photocatalytic Reaction of CO2 and H2O: Theoretical Studies

PubMed Central

Luo, Dongmei; Zhang, Ning; Hong, Sanguo; Wu, Huanwen; Liu, Zhihua

2010-01-01

Complexes (H2O/CO2, e–(H2O/CO2) and h+–(H2O/CO2)) in the reaction system of CO2 photoreduction with H2O were researched by B3LYP and MP2 methods along with natural bond orbital (NBO) analysis. Geometries of these complexes were optimized and frequencies analysis performed. H2O/CO2 captured photo-induced electron and hole produced e–(H2O/CO2) and h+–(H2O/CO2), respectively. The results revealed that CO2 and H2O molecules could be activated by the photo-induced electrons and holes, and each of these complexes possessed two isomers. Due to the effect of photo-induced electrons, the bond length of C=O and H-O were lengthened, while H-O bonds were shortened, influenced by holes. The infrared (IR) adsorption frequencies of these complexes were different from that of CO2 and H2O, which might be attributed to the synergistic effect and which could not be captured experimentally. PMID:21152274

Technological advances in CO2 conversion electro-biorefinery: A step toward commercialization.

PubMed

ElMekawy, Ahmed; Hegab, Hanaa M; Mohanakrishna, Gunda; Elbaz, Ashraf F; Bulut, Metin; Pant, Deepak

2016-09-01

The global atmospheric warming due to increased emissions of carbon dioxide (CO2) has attracted great attention in the last two decades. Although different CO2 capture and storage platforms have been proposed, the utilization of captured CO2 from industrial plants is progressively prevalent strategy due to concerns about the safety of terrestrial and aquatic CO2 storage. Two utilization forms were proposed, direct utilization of CO2 and conversion of CO2 to chemicals and energy products. The latter strategy includes the bioelectrochemical techniques in which electricity can be used as an energy source for the microbial catalytic production of fuels and other organic products from CO2. This approach is a potential technique in which CO2 emissions are not only reduced, but it also produce more value-added products. This review article highlights the different methodologies for the bioelectrochemical utilization of CO2, with distinctive focus on the potential opportunities for the commercialization of these techniques. Copyright © 2016 Elsevier Ltd. All rights reserved.

Natural analogues for CO2 storage sites - analysis of a global dataset

NASA Astrophysics Data System (ADS)

Miocic, Johannes; Gilfillan, Stuart; McDermott, Christopher; Haszeldine, R. Stuart

2013-04-01

Carbon Capture and Storage is the only industrial scale technology currently available to reduce CO2 emissions from fossil-fuelled power plants and large industrial source to the atmosphere and thus mitigate climate change. CO2 is captured at the source and transported to subsurface storage sites, such as depleted oil and gas fields or saline aquifers. In order to have an effect on emissions and to be considered safe it is crucial that the amount of CO2 leaking from storage sites to shallow aquifers or the surface remains very low (<1% over 1000 years). Some process that influence the safety of a reservoir, such as CO2-rock-brine interactions, can be studied using experiments on both laboratory and field-scale. However, long-term processes such as the development of leakage pathways can only be understood by either predictive modelling or by studying natural CO2 reservoirs as analogues for long term CO2 storage sites. Natural CO2 reservoirs have similar geological trapping mechanisms as anticipated for CO2 storage sites and often have held CO2 for a geological period of time (millions of years) without any indication for leakage. Yet, migration of CO2 from reservoirs to the surface is also common and evidenced by gas seeps such as springs and soil degassing. We have compiled and analysed a dataset comprising of more than 50 natural CO2 reservoirs from different settings all around the globe to provide an overview of the factors that are important for the retention of CO2 in the subsurface and what processes lead to leakage of CO2 from the reservoir. Initial results indicate that if the reservoir is found to be leaking, CO2 migration is along faults and not through caprock layers. This indicates that faults act as fluid pathways and play an important role when characterizing a storage site. Additionally, it appears that overpressure of the overburden and the state of CO2 in the reservoir influence the likelihood of migration and hence the safety of a reservoir.

Influence of Capillary Force and Buoyancy on CO2 Migration During CO2 Injection in a Sandstone Reservoir

NASA Astrophysics Data System (ADS)

Wu, H.; Pollyea, R.

2017-12-01

Carbon capture and sequestration (CCS) is one component of a broad carbon management portfolio designed to mitigate adverse effects of anthropogenic CO2 emissions. During CCS, capillary trapping is an important mechanism for CO2 isolation in the disposal reservoir, and, as a result, the distribution of capillary force is an important factor affecting CO2 migration. Moreover, the movement of CO2 being injected to the reservoir is also affected by buoyancy, which results from the density difference between CO2 and brine. In order to understand interactions between capillary force and buoyancy, we implement a parametric modeling experiment of CO2 injections in a sandstone reservoir for combinations of the van Genuchten capillary pressure model that bound the range of capillary pressure-saturation curves measured in laboratory experiments. We simulate ten years supercritical CO2 (scCO2) injections within a 2-D radially symmetric sandstone reservoir for five combinations of the van Genuchten model parameters λ and entry pressure (P0). Results are analyzed on the basis of a modified dimensionless ratio, ω, which is similar to the Bond number and defines the relationship between buoyancy pressure and capillary pressure. We show how parametric variability affects the relationship between buoyancy and capillary force, and thus controls CO2 plume geometry. These results indicate that when ω >1, then buoyancy governs the system and CO2 plume geometry is governed by upward flow. In contrast, when ω <1, then buoyancy is smaller than capillary force and lateral flow governs CO2 plume geometry. As a result, we show that the ω ratio is an easily implemented screening tool for qualitative assessment of reservoir performance.

Hybrid Encapsulated Ionic Liquids for Post-Combustion Carbon Dioxide (CO 2) Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brennecke, Joan F; Degnan, Jr, Thomas Francis; McCready, Mark J.

Ionic liquids (ILs) and Phase Change Ionic Liquids (PCILs) are excellent materials for selective removal of carbon dioxide from dilute post-combustion streams. However, they are typically characterized as having high viscosities, which impairs their effectiveness due to mass transfer limitations, caused by the high viscosities. In this project, we are examining the benefits of encapsulating ILs and PCILs in thin polymeric shells to produce particles of approximately 100 to 600 µm in diameter that can be used in a fluidized bed absorber. The particles are produced by microencapsulation of the ILs and PCILs in CO 2-permeable polymer shells. Here wemore » report on the encapsulation of the IL and PCIL materials, thermodynamic testing of the encapsulated materials, mass transfer measurements in both a fluidized bed and a packed bed, determination of the effect of impurities (SO 2, NO x and water) on the free and encapsulated IL and PCIL, recyclability of the CO 2 uptake, selection and synthesis of kg quantities of the IL and PCIL, identification of scale-up methods for encapsulation and production of a kg quantity of the PCIL, construction and shakedown of the laboratory scale unit to test the encapsulated particles for CO 2 capture ability and efficiency, use of our mass transfer model to predict mass transfer and identify optimal properties of the encapsulated particles, and initial testing of the encapsulated particles in the laboratory scale unit. We also show our attempts at developing shell materials that are resistant to water permeation. Overall, we have shown that the selected IL and PCIL can be successfully encapsulated in polymer shells and the methods scaled up to production levels. The IL/PCIL and encapsulated IL/PCIL react irreversibly with SO 2 and NO x so the CO 2 capture unit would need to be placed after the flue gas desulfurization and NO x reduction units. However, the reaction with CO 2 in the presence of water is completely reversible. Therefore, it is not necessary to exclude water from the capsules. Mass transfer in the fluidized and packed beds confirm that the fluidized bed arrangement is preferred and that the mass transfer can be predicted accurately by the rate based model that we have developed. Absorption and desorption experiments in the laboratory scale unit show good uptake and recyclability.« less

Pilot project at Hazira, India, for capture of carbon dioxide and its biofixation using microalgae.

PubMed

Yadav, Anant; Choudhary, Piyush; Atri, Neelam; Teir, Sebastian; Mutnuri, Srikanth

2016-11-01

The objective of the present study was to set up a small-scale pilot reactor at ONGC Hazira, Surat, for capturing CO 2 from vent gas. The studies were carried out for CO 2 capture by either using microalgae Chlorella sp. or a consortium of microalgae (Scenedesmus quadricauda, Chlorella vulgaris and Chlorococcum humicola). The biomass harvested was used for anaerobic digestion to produce biogas. The carbonation column was able to decrease the average 34 vol.% of CO 2 in vent gas to 15 vol.% of CO 2 in the outlet gas of the carbonation column. The yield of Chlorella sp. was found to be 18 g/m 2 /day. The methane yield was 386 l CH 4 /kg VS fed of Chlorella sp. whereas 228 l CH 4 /kg VS fed of the consortium of algae.

Co-firing coal and biomass blends and their influence on the post-combustion CO2 capture installation

NASA Astrophysics Data System (ADS)

Więckol-Ryk, Angelika; Smoliński, Adam

2017-10-01

Co-firing of biomass with coal for energy production is a well-known technology and plays an important role in the electricity sector. The post-combustion capture integrated with biomass-fired power plants (Bio-CCS) seems to be a new alternative for reducing greenhouse gas emissions. This study refers to the best known and advanced technology for post-combustion CO2 capture (PCC) based on a chemical absorption in monoethanolamine (MEA). The co-firing of hard coal with four types of biomass was investigated using a laboratory fixed bed reactor system. The comparison of gaseous products emitted from the combustion of coal and different biomass blends were determined using gas chromatography. Research proved that co-firing of biomass in fossil fuel power plants is beneficial for PCC process. It may also reduce the corrosion of CO2 capture installation. The oxygen concentration in the flue gases from hard coal combustion was comparable with the respective value for a fuel blend of biomass content of 20% w/w. It was also noted that an increase in biomass content in a sample from 20 to 40 % w/w increased the concentration of oxygen in the flue gas streams. However, this concentration should not have a significant impact on the rate of amine oxidative degradation.

A Diaminopropane-Appended Metal–Organic Framework Enabling Efficient CO 2 Capture from Coal Flue Gas via a Mixed Adsorption Mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Milner, Phillip J.; Siegelman, Rebecca L.; Forse, Alexander C.

A new diamine-functionalized metal–organic framework comprised of 2,2-dimethyl-1,3-diaminopropane (dmpn) appended to the Mg 2+ sites lining the channels of Mg 2(dobpdc) (dobpdc4– = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate) is characterized for the removal of CO 2 from the flue gas emissions of coal-fired power plants. Unique to members of this promising class of adsorbents, dmpn–Mg2(dobpdc) displays facile step-shaped adsorption of CO 2 from coal flue gas at 40 °C and near complete CO 2 desorption upon heating to 100 °C, enabling a high CO 2 working capacity (2.42 mmol/g, 9.1 wt %) with a modest 60 °C temperature swing. Evaluation of the thermodynamic parametersmore » of adsorption for dmpn–Mg 2(dobpdc) suggests that the narrow temperature swing of its CO 2 adsorption steps is due to the high magnitude of its differential enthalpy of adsorption (Δhads = -73 ± 1 kJ/mol), with a larger than expected entropic penalty for CO 2 adsorption (Δsads = -204 ± 4 J/mol·K) positioning the step in the optimal range for carbon capture from coal flue gas. In addition, thermogravimetric analysis and breakthrough experiments indicate that, in contrast to many adsorbents, dmpn–Mg 2(dobpdc) captures CO 2 effectively in the presence of water and can be subjected to 1000 humid adsorption/desorption cycles with minimal degradation. Solid-state 13C NMR spectra and single-crystal X-ray diffraction structures of the Zn analogue reveal that this material adsorbs CO 2 via formation of both ammonium carbamates and carbamic acid pairs, the latter of which are crystallographically verified for the first time in a porous material. Taken together, these properties render dmpn–Mg 2(dobpdc) one of the most promising adsorbents for carbon capture applications.« less

A Diaminopropane-Appended Metal-Organic Framework Enabling Efficient CO2 Capture from Coal Flue Gas via a Mixed Adsorption Mechanism.

PubMed

Milner, Phillip J; Siegelman, Rebecca L; Forse, Alexander C; Gonzalez, Miguel I; Runčevski, Tomče; Martell, Jeffrey D; Reimer, Jeffrey A; Long, Jeffrey R

2017-09-27

A new diamine-functionalized metal-organic framework comprised of 2,2-dimethyl-1,3-diaminopropane (dmpn) appended to the Mg 2+ sites lining the channels of Mg 2 (dobpdc) (dobpdc 4- = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate) is characterized for the removal of CO 2 from the flue gas emissions of coal-fired power plants. Unique to members of this promising class of adsorbents, dmpn-Mg 2 (dobpdc) displays facile step-shaped adsorption of CO 2 from coal flue gas at 40 °C and near complete CO 2 desorption upon heating to 100 °C, enabling a high CO 2 working capacity (2.42 mmol/g, 9.1 wt %) with a modest 60 °C temperature swing. Evaluation of the thermodynamic parameters of adsorption for dmpn-Mg 2 (dobpdc) suggests that the narrow temperature swing of its CO 2 adsorption steps is due to the high magnitude of its differential enthalpy of adsorption (Δh ads = -73 ± 1 kJ/mol), with a larger than expected entropic penalty for CO 2 adsorption (Δs ads = -204 ± 4 J/mol·K) positioning the step in the optimal range for carbon capture from coal flue gas. In addition, thermogravimetric analysis and breakthrough experiments indicate that, in contrast to many adsorbents, dmpn-Mg 2 (dobpdc) captures CO 2 effectively in the presence of water and can be subjected to 1000 humid adsorption/desorption cycles with minimal degradation. Solid-state 13 C NMR spectra and single-crystal X-ray diffraction structures of the Zn analogue reveal that this material adsorbs CO 2 via formation of both ammonium carbamates and carbamic acid pairs, the latter of which are crystallographically verified for the first time in a porous material. Taken together, these properties render dmpn-Mg 2 (dobpdc) one of the most promising adsorbents for carbon capture applications.

A Decadal Inversion of CO2 Using the Global Eulerian-Lagrangian Coupled Atmospheric Model (GELCA): Sensitivity to the Ground-Based Observation Network

NASA Technical Reports Server (NTRS)

Shirai, T.; Ishizawa, M.; Zhuravlev, R.; Ganshin, A.; Belikov, D.; Saito, M.; Oda, T.; Valsala, V.; Gomez-Pelaez, A. J.; Langenfelds, R.;

Developing a Comprehensive Risk Assessment Framework for Geological Storage CO 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duncan, Ian

2014-08-31

The operational risks for CCS projects include: risks of capturing, compressing, transporting and injecting CO₂; risks of well blowouts; risk that CO 2 will leak into shallow aquifers and contaminate potable water; and risk that sequestered CO 2 will leak into the atmosphere. This report examines these risks by using information on the risks associated with analogue activities such as CO 2 based enhanced oil recovery (CO 2-EOR), natural gas storage and acid gas disposal. We have developed a new analysis of pipeline risk based on Bayesian statistical analysis. Bayesian theory probabilities may describe states of partial knowledge, even perhapsmore » those related to non-repeatable events. The Bayesian approach enables both utilizing existing data and at the same time having the capability to adsorb new information thus to lower uncertainty in our understanding of complex systems. Incident rates for both natural gas and CO 2 pipelines have been widely used in papers and reports on risk of CO 2 pipelines as proxies for the individual risk created by such pipelines. Published risk studies of CO 2 pipelines suggest that the individual risk associated with CO2 pipelines is between 10 -3 and 10 -4, which reflects risk levels approaching those of mountain climbing, which many would find unacceptably high. This report concludes, based on a careful analysis of natural gas pipeline failures, suggests that the individual risk of CO 2 pipelines is likely in the range of 10-6 to 10-7, a risk range considered in the acceptable to negligible range in most countries. If, as is commonly thought, pipelines represent the highest risk component of CCS outside of the capture plant, then this conclusion suggests that most (if not all) previous quantitative- risk assessments of components of CCS may be orders of magnitude to high. The potential lethality of unexpected CO 2 releases from pipelines or wells are arguably the highest risk aspects of CO 2 enhanced oil recovery (CO2-EOR), carbon capture, and storage (CCS). Assertions in the CCS literature, that CO 2 levels of 10% for ten minutes, or 20 to 30% for a few minutes are lethal to humans, are not supported by the available evidence. The results of published experiments with animals exposed to CO 2, from mice to monkeys, at both normal and depleted oxygen levels, suggest that lethal levels of CO 2 toxicity are in the range 50 to 60%. These experiments demonstrate that CO 2 does not kill by asphyxia, but rather is toxic at high concentrations. It is concluded that quantitative risk assessments of CCS have overestimated the risk of fatalities by using values of lethality a factor two to six lower than the values estimated in this paper. In many dispersion models of CO 2 releases from pipelines, no fatalities would be predicted if appropriate levels of lethality for CO 2 had been used in the analysis.« less

Poly(ethylenimine)-Functionalized Monolithic Alumina Honeycomb Adsorbents for CO2 Capture from Air.

PubMed

Sakwa-Novak, Miles A; Yoo, Chun-Jae; Tan, Shuai; Rashidi, Fereshteh; Jones, Christopher W

2016-07-21

The development of practical and effective gas-solid contactors is an important area in the development of CO2 capture technologies. Target CO2 capture applications, such as postcombustion carbon capture and sequestration (CCS) from power plant flue gases or CO2 extraction directly from ambient air (DAC), require high flow rates of gas to be processed at low cost. Extruded monolithic honeycomb structures, such as those employed in the catalytic converters of automobiles, have excellent potential as structured contactors for CO2 adsorption applications because of the low pressure drop imposed on fluid moving through the straight channels of such structures. Here, we report the impregnation of poly(ethylenimine) (PEI), an effective aminopolymer reported commonly for CO2 separation, into extruded monolithic alumina to form structured CO2 sorbents. These structured sorbents are first prepared on a small scale, characterized thoroughly, and compared with powder sorbents with a similar composition. Despite consistent differences observed in the filling of mesopores with PEI between the monolithic and powder sorbents, their performance in CO2 adsorption is similar across a range of PEI contents. A larger monolithic cylinder (1 inch diameter, 4 inch length) is evaluated under conditions closer to those that might be used in large-scale applications and shows a similar performance to the smaller monoliths and powders tested initially. This larger structure is evaluated over five cycles of CO2 adsorption and steam desorption and demonstrates a volumetric capacity of 350 molCO2  m-3monolith and an equilibration time of 350 min under a 0.4 m s(-1) linear flow velocity through the monolith channels using 400 ppm CO2 in N2 as the adsorption gas at 30 °C. This volumetric capacity surpasses that of a similar technology considered previously, which suggested that CO2 could be removed from air at an operating cost as low as $100 per ton. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Demonstration of Advanced CO 2 Capture Process Improvements for Coal-Fired Flue Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carroll, John

This document summarizes the activities of Cooperative Agreement DE-FE0026590, “Demonstration of Advanced CO 2 Capture Process Improvements for Coal-Fired Flue Gas” during the performance period of October 1, 2015 through May 31, 2017. This project was funded by the U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL). Southern Company Services, Inc. (SCS) was the prime contractor and co-funder of the project. Mitsubishi Heavy Industries America (MHIA) and AECOM were project team members. The overall project objective was to improve costs, energy requirements, and performance of an existing amine-based CO 2 capture process. This will occur via improvements inmore » three areas: 1. Reboiler design – The first objective of the program was to demonstrate performance of an integrated stripper/reboiler (termed Built-in Reboiler, or BIR) to reduce footprint, capital costs, and integration issues of the current technology. 2. Particulate management – The second objective was to carry out a Particulate Matter Management (PMM) test. This has the potential to reduce operating costs and capital costs due to the reduced or eliminated need for mechanical filtration. 3. Solvent – The third objective was to carry out a new solvent test plan (referred to as NSL) to demonstrate a new solvent (termed New Solvent A), which is expected to reduce regeneration steam. The bulk price is also expected to be lower than KS-1, which is the current solvent used in this process. NSL testing would include baseline testing, optimization, long term testing, solvent reclamation testing, and final inspection. These combine to form the Advanced Carbon Capture (ACC) technology. Much of this work will be applicable to generic solvent processes, especially in regards to improved reboiler design, and focused to meet or exceed the DOE’s overall carbon capture performance goals of 90% CO 2 capture rate with 95% CO 2 purity at a cost of $40/tonne of CO 2 by 2025 and at a cost of electricity (COE) 30% less than baseline CO 2 capture approaches by 2030. This project was divided into two phases. Phase 1 is the planning phase, and Phase 2 is the construction, operations, testing, and analysis phase. A down select occurred after Phase 1. Phase 1 activities were carried out during this reporting period, and therefore, Phase 1 activities are solely considered in this report. The project was not selected for Phase 2 funding.« less

Thermodynamic Equilibrium Solubility of Diethanolamine – N-Butyl-1-Methylpyrrolidinium Dicyanamide [DEABMPYRR DCA] Mixtures for Carbon Dioxide Capture

NASA Astrophysics Data System (ADS)

Salleh, R. M.; Jamaludin, S. N.

2018-05-01

Solubility data of carbon dioxide (CO2) in aqueous Diethanolamine (DEA) blended with pyrrolidinium-based ionic liquid: N-Butyl-1-Methylpyrrolidinium Dıcyanamıde [Bmpyrr][DCA] are presented at various temperatures (313.15K-333.15K) and pressure up to about 700 psi. The concentration of [Bmpyrr][DCA] ranges from 0-10wt% and 30-40wt% for DEA. The solubility of CO2 was evaluated by measuring the pressure drop in high pressure stirred absorption cell reactor. The CO2 loading in all studied mixtures increases with an increase in CO2 partial pressure and decreases with temperature. It was also found that the CO2 loading capacity decrease as the concentration of [Bmpyrr][DCA] increases. The experimental data were correlated as a function of temperature and CO2 partial pressure to predict the solubility of CO2 in the mixtures. It was found that the model predicted results in a good agreement with experimental value.

40 CFR 98.422 - GHGs to report.

Code of Federal Regulations, 2010 CFR

2010-07-01

... GREENHOUSE GAS REPORTING Suppliers of Carbon Dioxide § 98.422 GHGs to report. (a) Mass of CO2 captured from each production process unit. (b) Mass of CO2 extracted from each CO2 production wells. (c) Mass of CO2 imported. (d) Mass of CO2 exported. ...

Robust Immobilized Amine CO 2 Sorbent Pellets Utilizing a Poly(Chloroprene) Polymer Binder and Fly Ash Additive

DOE PAGES

Wilfong, Walter Christopher; Kail, Brian W.; Howard, Bret H.; ...

2016-08-04

Pelletization of ca. 50 wt % amine/silica carbon dioxide sorbents was achieved with the novel combination of fly ash (FA) as a strength additive and hydrophobic poly(chloroprene) (PC) as a binder. The PC content and overall synthesis procedure of these materials were optimized to produce pellets, labeled as FA/E100-S_(20/80)_12.2, with the highest ball-mill attrition resistance (<0.5 wt % by fines, 24 h) and maximum CO 2 capture capacity of 1.78 mmol CO 2 g -1. The strength of the pellets was attributed to hydrogen-bonding of the relatively homogeneous PC network with the interlocked FA and BIAS particles (DRIFTS, SEM-EDS). Themore » low degradation of 3–4 % in the pellet's CO 2 capture capacity under both dry TGA (7.5 h) and practical fixed-bed (6.5 h dry; 4.5 h humid,≈5 vol % H 2O) CO 2 adsorption–desorption conditions highlights the pellet's excellent cyclic stability. These robust pellet characteristics make PC/FA/sorbent materials promising for commercial scale, point-source CO 2 capture.« less

The Ca-looping process for CO2 capture and energy storage: role of nanoparticle technology

NASA Astrophysics Data System (ADS)

Valverde, Jose Manuel

2018-02-01

The calcium looping (CaL) process, based on the cyclic carbonation/calcination of CaO, has come into scene in the last years with a high potential to be used in large-scale technologies aimed at mitigating global warming. In the CaL process for CO2 capture, the CO2-loaded flue gas is used to fluidize a bed of CaO particles at temperatures around 650 °C. The carbonated particles are then circulated into a calciner reactor wherein the CaO solids are regenerated at temperatures near 950 °C under high CO2 concentration. Calcination at such harsh conditions causes a marked sintering and loss of reactivity of the regenerated CaO. This main drawback could be however compensated from the very low cost of natural CaO precursors such as limestone or dolomite. Another emerging application of the CaL process is thermochemical energy storage (TCES) in concentrated solar power (CSP) plants. Importantly, carbonation/calcination conditions to maximize the global CaL-CSP plant efficiency could differ radically from those used for CO2 capture. Thus, carbonation could be carried out at high temperatures under high CO2 partial pressure for maximum efficiency, whereas the solids could be calcined at relatively low temperatures in the absence of CO2 to promote calcination. Our work highlights the critical role of carbonation/calcination conditions on the performance of CaO derived from natural precursors. While conditions in the CaL process for CO2 capture lead to a severe CaO deactivation with the number of cycles, the same material may exhibit a high and stable conversion at optimum CaL-CSP conditions. Moreover, the type of CaL conditions influences critically the reaction kinetics, which plays a main role on the optimization of relevant operation parameters such as the residence time in the reactors. This paper is devoted to a brief review on the latest research activity in our group concerning these issues as well as the possible role of nanoparticle technology to enhance the activity of Ca-based materials at CaL conditions for CO2 capture and energy storage.

Effects of water vapor pretreatment time and reaction temperature on CO(2) capture characteristics of a sodium-based solid sorbent in a bubbling fluidized-bed reactor.

PubMed

Seo, Yongwon; Jo, Sung-Ho; Ryu, Chong Kul; Yi, Chang-Keun

2007-10-01

CO(2) capture from flue gas using a sodium-based solid sorbent was investigated in a bubbling fluidized-bed reactor. Carbonation and regeneration temperature on CO(2) removal was determined. The extent of the chemical reactivity after carbonation or regeneration was characterized via (13)C NMR. In addition, the physical properties of the sorbent such as pore size, pore volume, and surface area after carbonation or regeneration were measured by gas adsorption method (BET). With water vapor pretreatment, near complete CO(2) removal was initially achieved and maintained for about 1-2min at 50 degrees C with 2s gas residence time, while without proper water vapor pretreatment CO(2) removal abruptly decreased from the beginning. Carbonation was effective at the lower temperature over the 50-70 degrees C temperature range, while regeneration more effective at the higher temperature over the 135-300 degrees C temperature range. To maintain the initial 90% CO(2) removal, it would be necessary to keep the regeneration temperature higher than about 135 degrees C. The results obtained in this study can be used as basic data for designing and operating a large scale CO(2) capture process with two fluidized-bed reactors.

Bifunctional application of sodium cobaltate as a catalyst and captor through CO oxidation and subsequent CO 2 chemisorption processes

DOE PAGES

Vera, Elizabeth; Alcántar-Vázquez, Brenda; Duan, Yuhua; ...

2015-12-21

The potential bifunctional mechanism of sodium cobaltate (NaCoO 2) in the catalysis of CO oxidation and subsequent CO 2 chemisorption was systematically analysed. Different catalytic and gravimetric experiments were performed dynamically and isothermally at multiple temperatures. Initially, the CO oxidation process was evaluated using a catalytic reactor connected to a gas chromatograph. Once the production of CO 2 was confirmed, its chemisorption capacity with NaCoO 2 was studied gravimetrically. Catalytic and gravimetric analysis products were studied by XRD, FTIR and SEM to elucidate the double reaction mechanism. Sodium cobaltate exhibited interesting catalytic properties over a wide temperature range, although themore » NaCoO 2 crystalline structure and chemical composition changed during the CO 2 capture process. Furthermore, all the experiments were theoretically supported by first-principles density functional theory thermodynamic calculations. Finally, the calculated thermodynamic properties of the CO oxidation and CO 2 capture reactions with NaCoO 2 under different oxidation conditions were in good agreement with the experimental measurements.« less

Near-Zero Emissions Oxy-Combustion Flue Gas Purification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minish Shah; Nich Degenstein; Monica Zanfir

2012-06-30

The objectives of this project were to carry out an experimental program to enable development and design of near zero emissions (NZE) CO{sub 2} processing unit (CPU) for oxy-combustion plants burning high and low sulfur coals and to perform commercial viability assessment. The NZE CPU was proposed to produce high purity CO{sub 2} from the oxycombustion flue gas, to achieve > 95% CO{sub 2} capture rate and to achieve near zero atmospheric emissions of criteria pollutants. Two SOx/NOx removal technologies were proposed depending on the SOx levels in the flue gas. The activated carbon process was proposed for power plantsmore » burning low sulfur coal and the sulfuric acid process was proposed for power plants burning high sulfur coal. For plants burning high sulfur coal, the sulfuric acid process would convert SOx and NOx in to commercial grade sulfuric and nitric acid by-products, thus reducing operating costs associated with SOx/NOx removal. For plants burning low sulfur coal, investment in separate FGD and SCR equipment for producing high purity CO{sub 2} would not be needed. To achieve high CO{sub 2} capture rates, a hybrid process that combines cold box and VPSA (vacuum pressure swing adsorption) was proposed. In the proposed hybrid process, up to 90% of CO{sub 2} in the cold box vent stream would be recovered by CO{sub 2} VPSA and then it would be recycled and mixed with the flue gas stream upstream of the compressor. The overall recovery from the process will be > 95%. The activated carbon process was able to achieve simultaneous SOx and NOx removal in a single step. The removal efficiencies were >99.9% for SOx and >98% for NOx, thus exceeding the performance targets of >99% and >95%, respectively. The process was also found to be suitable for power plants burning both low and high sulfur coals. Sulfuric acid process did not meet the performance expectations. Although it could achieve high SOx (>99%) and NOx (>90%) removal efficiencies, it could not produce by-product sulfuric and nitric acids that meet the commercial product specifications. The sulfuric acid will have to be disposed of by neutralization, thus lowering the value of the technology to same level as that of the activated carbon process. Therefore, it was decided to discontinue any further efforts on sulfuric acid process. Because of encouraging results on the activated carbon process, it was decided to add a new subtask on testing this process in a dual bed continuous unit. A 40 days long continuous operation test confirmed the excellent SOx/NOx removal efficiencies achieved in the batch operation. This test also indicated the need for further efforts on optimization of adsorption-regeneration cycle to maintain long term activity of activated carbon material at a higher level. The VPSA process was tested in a pilot unit. It achieved CO{sub 2} recovery of > 95% and CO{sub 2} purity of >80% (by vol.) from simulated cold box feed streams. The overall CO{sub 2} recovery from the cold box VPSA hybrid process was projected to be >99% for plants with low air ingress (2%) and >97% for plants with high air ingress (10%). Economic analysis was performed to assess value of the NZE CPU. The advantage of NZE CPU over conventional CPU is only apparent when CO{sub 2} capture and avoided costs are compared. For greenfield plants, cost of avoided CO{sub 2} and cost of captured CO{sub 2} are generally about 11-14% lower using the NZE CPU compared to using a conventional CPU. For older plants with high air intrusion, the cost of avoided CO{sub 2} and capture CO{sub 2} are about 18-24% lower using the NZE CPU. Lower capture costs for NZE CPU are due to lower capital investment in FGD/SCR and higher CO{sub 2} capture efficiency. In summary, as a result of this project, we now have developed one technology option for NZE CPU based on the activated carbon process and coldbox-VPSA hybrid process. This technology is projected to work for both low and high sulfur coal plants. The NZE CPU technology is projected to achieve near zero stack emissions, produce high purity CO{sub 2} relatively free of trace impurities and achieve ~99% CO{sub 2} capture rate while lowering the CO{sub 2} capture costs.« less

77 FR 58533 - Notice of Availability of the Draft Environmental Impact Statement for the W.A. Parish Post...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-21

....A. Parish Post-Combustion CO 2 Capture and Sequestration Project, Southeastern TX AGENCY: U.S... availability of the Draft Environmental Impact Statement for the W.A. Parish Post-Combustion Carbon Dioxide.... Parish Post-Combustion CO 2 Capture and Sequestration Project (Parish PCCS Project). NRG's proposed...

Does Terrestrial Carbon Explain Lake Superior Model-Data pCO2 Discrepancy?

NASA Astrophysics Data System (ADS)

Bennington, V.; McKinley, G. A.; Atilla, N.; Kimura, N.; Urban, N.; Wu, C.; Desai, A.

2008-12-01

As part of the CyCLeS project, a three-dimensional hydrodynamic model (MITgcm) was coupled to a medium- complexity ecosystem model and applied to Lake Superior in order to constrain the seasonal cycle of lake pCO2 and air-lake fluxes of CO2. Previous estimates of CO2 emissions from the lake, while very large, were based on field measurements of very limited spatial and temporal extent. The model allows a more realistic extrapolation from the limited data by incorporation of lake-wide circulation and food web dynamics. A large discrepancy (200 uatm) between observations and model-predicted pCO2 during spring suggests a significant input of terrestrial carbon into the lake. The physical model has 10-km horizontal resolution with 29 vertical layers, ten of which are in the top 50 m of the water column. The model is forced by interpolated meteorological data obtained from land-based weather stations, buoys, and other measurements. Modeled surface temperatures compare well to satellite- based surface water temperature images derived from NOAA AVHRR (Advanced Very High Resolution Radiometer), though there are regional patterns of bias that suggest errors in the heat flux forcing. Growth of two classes of phytoplankton is modeled as a function of temperature, light, and nutrients. One grazer preys upon all phytoplankton. The cycles of carbon and phosphorous are explicitly modeled throughout the water column. The model is able to replicate the observed seasonal cycle of lake chlorophyll and the deep chlorophyll maximum. The model is unable to capture the magnitude of observed CO2 super-saturation during spring without considering external carbon inputs to the lake. Simple box model results suggest that the estimated pool of terrestrial carbon in the lake (17 TgC) must remineralize with a timescale of months during spring in order to account for the model/data pCO2 difference. River inputs and enhanced remineralization in spring due to photo-oxidation are other mechanisms considered to explain the discrepancy between model predictions and observations of pCO2. Model results suggest that year-round and lake-wide direct measurements of pCO2 would help to better constrain the lake carbon cycle.

Microbe-driven turnover offsets mineral-mediated storage of soil carbon under elevated CO2

NASA Astrophysics Data System (ADS)

Sulman, Benjamin N.; Phillips, Richard P.; Oishi, A. Christopher; Shevliakova, Elena; Pacala, Stephen W.

2014-12-01

The sensitivity of soil organic carbon (SOC) to changing environmental conditions represents a critical uncertainty in coupled carbon cycle-climate models. Much of this uncertainty arises from our limited understanding of the extent to which root-microbe interactions induce SOC losses (through accelerated decomposition or `priming') or indirectly promote SOC gains (via `protection' through interactions with mineral particles). We developed a new SOC model to examine priming and protection responses to rising atmospheric CO2. The model captured disparate SOC responses at two temperate free-air CO2 enrichment (FACE) experiments. We show that stabilization of `new' carbon in protected SOC pools may equal or exceed microbial priming of `old' SOC in ecosystems with readily decomposable litter and high clay content (for example, Oak Ridge). In contrast, carbon losses induced through priming dominate the net SOC response in ecosystems with more resistant litters and lower clay content (for example, Duke). The SOC model was fully integrated into a global terrestrial carbon cycle model to run global simulations of elevated CO2 effects. Although protected carbon provides an important constraint on priming effects, priming nonetheless reduced SOC storage in the majority of terrestrial areas, partially counterbalancing SOC gains from enhanced ecosystem productivity.

CO2 Dissociation using the Versatile Atmospheric Dielectric Barrier Discharge Experiment (VADER)

NASA Astrophysics Data System (ADS)

Lindon, Michael Allen

As of 2013, the Carbon Dioxide Information Analysis Center (CDIAC) estimates that the world emits approximately 36 trillion metric tons of Carbon Dioxide (CO2) into the atmosphere every year. These large emissions have been correlated to global warming trends that have many consequences across the globe, including glacial retraction, ocean acidification and increased severity of weather events. With green technologies still in the infancy stage, it can be expected that CO2 emissions will stay this way for along time to come. Approximately 41% of the emissions are due to electricity production, which pump out condensed forms of CO2. This danger to our world is why research towards new and innovative ways of controlling CO2 emissions from these large sources is necessary. As of now, research is focused on two primary methods of CO2 reduction from condensed CO2 emission sources (like fossil fuel power plants): Carbon Capture and Sequestration (CCS) and Carbon Capture and Utilization (CCU). CCS is the process of collecting CO2 using absorbers or chemicals, extracting the gas from those absorbers and finally pumping the gas into reservoirs. CCU on the other hand, is the process of reacting CO2 to form value added chemicals, which can then be recycled or stored chemically. A Dielectric Barrier discharge (DBD) is a pulsed, low temperature, non-thermal, atmospheric pressure plasma which creates high energy electrons suitable for dissociating CO2 into its components (CO and O) as one step in the CCU process. Here I discuss the viability of using a DBD for CO2 dissociation on an industrial scale as well as the fundamental physics and chemistry of a DBD for CO2 dissociation. This work involved modeling the DBD discharge and chemistry, which showed that there are specific chemical pathways and plasma parameters that can be adjusted to improve the CO2 reaction efficiencies and rates. Experimental studies using the Versatile Atmospheric dielectric barrier Discharge ExpeRiment (VADER) demonstrated how different factors, like voltage, frequency and the addition of a photocatalyst, change the efficiency of CO2 dissociation in VADER and the plasma chemistry involved.

Single-component and binary CO2 and H2O adsorption of amine-functionalized cellulose.

PubMed

Gebald, Christoph; Wurzbacher, Jan A; Borgschulte, Andreas; Zimmermann, Tanja; Steinfeld, Aldo

2014-02-18

A fundamental analysis of single-component and binary CO2 and H2O adsorption of amine-functionalized nanofibrillated cellulose is carried out in the temperature range of 283-353 K and at CO2 partial pressures in the range of 0.02-105 kPa, where the ultralow partial pressure range is relevant for the direct capture of CO2 from atmospheric air. Single-component CO2 and H2O adsorption experimental data are fitted to the Toth and Guggenheim-Anderson-de Boer models, respectively. Corresponding heats of adsorption, derived from explicit solutions of the van't Hoff equation, are -50 kJ/mol CO2 and -48.8 kJ/mol H2O. Binary CO2/H2O adsorption measurements for humid air reveal that the presence of H2O at 2.55 kPa enhances CO2 adsorption, while the presence of CO2 at 0.045 kPa does not influence H2O adsorption. The energy demand of the temperature-vacuum-swing adsorption/desorption cycle for delivering pure CO2 from air increases significantly with H2O adsorption and indicates the need to reduce the hygroscopicity of the adsorbent.

Large Pilot Scale Testing of Linde/BASF Post-Combustion CO 2 Capture Technology at the Abbott Coal-Fired Power Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Brien, Kevin C.

The work summarized in this report is the first step towards a project that will re-train and create jobs for personnel in the coal industry and continue regional economic development to benefit regions impacted by previous downturns. The larger project is aimed at capturing ~300 tons/day (272 metric tonnes/day) CO 2 at a 90% capture rate from existing coal- fired boilers at the Abbott Power Plant on the campus of University of Illinois (UI). It will employ the Linde-BASF novel amine-based advanced CO 2 capture technology, which has already shown the potential to be cost-effective, energy efficient and compact atmore » the 0.5-1.5 MWe pilot scales. The overall objective of the project is to design and install a scaled-up system of nominal 15 MWe size, integrate it with the Abbott Power Plant flue gas, steam and other utility systems, and demonstrate the viability of continuous operation under realistic conditions with high efficiency and capacity. The project will also begin to build a workforce that understands how to operate and maintain the capture plants by including students from regional community colleges and universities in the operation and evaluation of the capture system. This project will also lay the groundwork for follow-on projects that pilot utilization of the captured CO 2 from coal-fired power plants. The net impact will be to demonstrate a replicable means to (1) use a standardized procedure to evaluate power plants for their ability to be retrofitted with a pilot capture unit; (2) design and construct reliable capture systems based on the Linde-BASF technology; (3) operate and maintain these systems; (4) implement training programs with local community colleges and universities to establish a workforce to operate and maintain the systems; and (5) prepare to evaluate at the large pilot scale level various methods to utilize the resulting captured CO 2. Towards the larger project goal, the UI-led team, together with Linde, has completed a preliminary design for the carbon capture pilot plant with basic engineering and cost estimates, established permitting needs, identified approaches to address Environmental, Health, and Safety concerns related to pilot plant installation and operation, developed approaches for long-term use of the captured carbon, and established strategies for workforce development and job creation that will re-train coal operators to operate carbon capture plants. This report describes Phase I accomplishments and demonstrates that the project team is well-prepared for full implementation of Phase 2, to design, build, and operate the carbon capture pilot plant.« less

The Chemical Route to a Carbon Dioxide Neutral World.

PubMed

Martens, Johan A; Bogaerts, Annemie; De Kimpe, Norbert; Jacobs, Pierre A; Marin, Guy B; Rabaey, Korneel; Saeys, Mark; Verhelst, Sebastian

2017-03-22

Excessive CO 2 emissions in the atmosphere from anthropogenic activity can be divided into point sources and diffuse sources. The capture of CO 2 from flue gases of large industrial installations and its conversion into fuels and chemicals with fast catalytic processes seems technically possible. Some emerging technologies are already being demonstrated on an industrial scale. Others are still being tested on a laboratory or pilot scale. These emerging chemical technologies can be implemented in a time window ranging from 5 to 20 years. The massive amounts of energy needed for capturing processes and the conversion of CO 2 should come from low-carbon energy sources, such as tidal, geothermal, and nuclear energy, but also, mainly, from the sun. Synthetic methane gas that can be formed from CO 2 and hydrogen gas is an attractive renewable energy carrier with an existing distribution system. Methanol offers advantages as a liquid fuel and is also a building block for the chemical industry. CO 2 emissions from diffuse sources is a difficult problem to solve, particularly for CO 2 emissions from road, water, and air transport, but steady progress in the development of technology for capturing CO 2 from air is being made. It is impossible to ban carbon from the entire energy supply of mankind with the current technological knowledge, but a transition to a mixed carbon-hydrogen economy can reduce net CO 2 emissions and ultimately lead to a CO 2 -neutral world. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Geologic Carbon Sequestration: Mitigating Climate Change by Injecting CO2 Underground (LBNL Summer Lecture Series)

ScienceCinema

Oldenburg, Curtis M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division

2018-05-07

Summer Lecture Series 2009: Climate change provides strong motivation to reduce CO2 emissions from the burning of fossil fuels. Carbon dioxide capture and storage involves the capture, compression, and transport of CO2 to geologically favorable areas, where its injected into porous rock more than one kilometer underground for permanent storage. Oldenburg, who heads Berkeley Labs Geologic Carbon Sequestration Program, will focus on the challenges, opportunities, and research needs of this innovative technology.

Hierarchical calibration and validation of computational fluid dynamics models for solid sorbent-based carbon capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lai, Canhai; Xu, Zhijie; Pan, Wenxiao

2016-01-01

To quantify the predictive confidence of a solid sorbent-based carbon capture design, a hierarchical validation methodology—consisting of basic unit problems with increasing physical complexity coupled with filtered model-based geometric upscaling has been developed and implemented. This paper describes the computational fluid dynamics (CFD) multi-phase reactive flow simulations and the associated data flows among different unit problems performed within the said hierarchical validation approach. The bench-top experiments used in this calibration and validation effort were carefully designed to follow the desired simple-to-complex unit problem hierarchy, with corresponding data acquisition to support model parameters calibrations at each unit problem level. A Bayesianmore » calibration procedure is employed and the posterior model parameter distributions obtained at one unit-problem level are used as prior distributions for the same parameters in the next-tier simulations. Overall, the results have demonstrated that the multiphase reactive flow models within MFIX can be used to capture the bed pressure, temperature, CO2 capture capacity, and kinetics with quantitative accuracy. The CFD modeling methodology and associated uncertainty quantification techniques presented herein offer a solid framework for estimating the predictive confidence in the virtual scale up of a larger carbon capture device.« less

A Simplified Model for Multiphase Leakage through Faults with Applications for CO2 Storage

NASA Astrophysics Data System (ADS)

Watson, F. E.; Doster, F.

2017-12-01

In the context of geological CO2 storage, faults in the subsurface could affect storage security by acting as high permeability pathways which allow CO2 to flow upwards and away from the storage formation. To assess the likelihood of leakage through faults and the impacts faults might have on storage security numerical models are required. However, faults are complex geological features, usually consisting of a fault core surrounded by a highly fractured damage zone. A direct representation of these in a numerical model would require very fine grid resolution and would be computationally expensive. Here, we present the development of a reduced complexity model for fault flow using the vertically integrated formulation. This model captures the main features of the flow but does not require us to resolve the vertical dimension, nor the fault in the horizontal dimension, explicitly. It is thus less computationally expensive than full resolution models. Consequently, we can quickly model many realisations for parameter uncertainty studies of CO2 injection into faulted reservoirs. We develop the model based on explicitly simulating local 3D representations of faults for characteristic scenarios using the Matlab Reservoir Simulation Toolbox (MRST). We have assessed the impact of variables such as fault geometry, porosity and permeability on multiphase leakage rates.

A catalytic role of surface silanol groups in CO2 capture on the amine-anchored silica support.

PubMed

Cho, Moses; Park, Joonho; Yavuz, Cafer T; Jung, Yousung

2018-05-03

A new mechanism of CO2 capture on the amine-functionalized silica support is demonstrated using density functional theory calculations, in which the silica surface not only acts as a support to anchor amines, but also can actively participate in the CO2 capture process through a facile proton transfer reaction with the amine groups. The surface-mediated proton transfer mechanism in forming a carbamate-ammonium product has lower kinetic barrier (8.1 kcal mol-1) than the generally accepted intermolecular mechanism (12.7 kcal mol-1) under dry conditions, and comparable to that of the water-assisted intermolecular mechanism (6.0 kcal mol-1) under humid conditions. These findings suggest that the CO2 adsorption on the amine-anchored silica surface would mostly occur via the rate-determining proton transfer step that is catalyzed by the surface silanol groups.

Flying MOFs: polyamine-containing fluidized MOF/SiO 2 hybrid materials for CO 2 capture from post-combustion flue gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luz, Ignacio; Soukri, Mustapha; Lail, Marty

Solid-state synthesis ensures a high loading and well dispersed growth of a large collection of metal–organic framework (MOF) nanostructures within a series of commercially available mesoporous silica allowing to render MOFs into fluidized solid sorbents for CO 2 capture from post-combustion flue gas in a fluidized-bed reactor.

Flying MOFs: polyamine-containing fluidized MOF/SiO 2 hybrid materials for CO 2 capture from post-combustion flue gas

DOE PAGES

Luz, Ignacio; Soukri, Mustapha; Lail, Marty

2018-01-01

Solid-state synthesis ensures a high loading and well dispersed growth of a large collection of metal–organic framework (MOF) nanostructures within a series of commercially available mesoporous silica allowing to render MOFs into fluidized solid sorbents for CO 2 capture from post-combustion flue gas in a fluidized-bed reactor.

Supercritical CO2 Migration under Cross-Bedded Structures: Outcrop Analog from the Jurassic Navajo Sandstone

NASA Astrophysics Data System (ADS)

Lee, S.; Allen, J.; Han, W.; Lu, C.; McPherson, B. J.

2011-12-01

Jurassic aeolian sandstones (e.g. Navajo and White Rim Sandstones) on the Colorado Plateau of Utah have been considered potential sinks for geologic CO2 sequestration due to their regional lateral continuity, thickness, high porosity and permeability, presence of seal strata and proximity to large point sources of anthropogenic CO2. However, aeolian deposits usually exhibit inherent internal complexities induced by migrating bedforms of different sizes and their resulting bounding surfaces. Therefore, CO2 plume migration in such complex media should be well defined and successively linked in models for better characterization of the plume behavior. Based on an outcrop analog of the upper Navajo Sandstone in the western flank of the San Rafael Swell, Utah, we identified five different bedform types with dune and interdune facies to represent the spatial continuity of lithofacies units. Using generated 3D geometrical facies patterns of cross-bedded structures in the Navajo Sandstone, we performed numerical simulations to understand the detailed behavior of CO2 plume migration under the different cross-bedded bedforms. Our numerical simulation results indicate that cross-bedded structures (bedform types) play an important role on governing the rate and directionality of CO2 migration, resulting in changes of imbibition processes of CO2. CO2 migration tends to follow wind ripple laminations and reactivation surfaces updip. Our results suggest that geologically-based upscaling of CO2 migration is crucial in cross-bedded formations as part of reservoir or basin scale models. Furthermore, comparative modeling studies between 3D models and 2D cross-sections extracted from 3D models showed the significant three-dimensional interplay in a cross-bedded structure and the need to correctly capture the geologic heterogeneity to predict realistic CO2 plume behavior. Our outcrop analog approach presented in this study also demonstrates an alternative method for assessing geologic CO2 storage in deep formations when scarce data is available.

Evaluating the efficacy of amino acids as CO2 capturing agents: a first principles investigation.

PubMed

Hussain, M Althaf; Soujanya, Yarasi; Sastry, G Narahari

2011-10-01

Comprehension of the basic concepts for the design of systems for CO2 adsorption is imperative for increasing interest in technology for CO2 capture from the effluents. The efficacy of 20 naturally occurring amino acids (AAs) is demonstrated as the most potent CO2 capturing agents in the process of chemical absorption and physisorption through a systematic computational study using highly parametrized M05-2X/6-311+G(d,p) method. The ability of AAs to bind CO2 both in the noncovalent and covalent fashion and presence of multiple adsorption sites with varying magnitude of binding strengths in all 20 AAs makes them as most promising materials in the process of physisorption. The binding energies (BEs) estimating the strength of noncovalent interaction of AAs and CO2 are calculated and results are interpreted in terms of the nature and strength of the various types of cooperative interactions which are present. The study underlines the possibility to engineer the porous solid materials with extended networks by judiciously employing AA chains as linkers which can substantially augment their efficacy. Results show that a significant increase in the CO2···AA affinity is achieved in the case of AAs with polar neutral side chains. Furthermore, the study proposes AAs as effective alternatives to alkanolamines in chemical dissolution of CO2.

Early atmospheric detection of carbon dioxide from carbon capture and storage sites.

PubMed

Pak, Nasrin Mostafavi; Rempillo, Ofelia; Norman, Ann-Lise; Layzell, David B

2016-08-01

The early atmospheric detection of carbon dioxide (CO2) leaks from carbon capture and storage (CCS) sites is important both to inform remediation efforts and to build and maintain public support for CCS in mitigating greenhouse gas emissions. A gas analysis system was developed to assess the origin of plumes of air enriched in CO2, as to whether CO2 is from a CCS site or from the oxidation of carbon compounds. The system measured CO2 and O2 concentrations for different plume samples relative to background air and calculated the gas differential concentration ratio (GDCR = -ΔO2/ΔCO2). The experimental results were in good agreement with theoretical calculations that placed GDCR values for a CO2 leak at 0.21, compared with GDCR values of 1-1.8 for the combustion of carbon compounds. Although some combustion plume samples deviated in GDCR from theoretical, the very low GDCR values associated with plumes from CO2 leaks provided confidence that this technology holds promise in providing a tool for the early detection of CO2 leaks from CCS sites. This work contributes to the development of a cost-effective technology for the early detection of leaks from sites where CO2 has been injected into the subsurface to enhance oil recovery or to permanently store the gas as a strategy for mitigating climate change. Such technology will be important in building public confidence regarding the safety and security of carbon capture and storage sites.

Alternative stripper configurations for CO{sub 2} capture by aqueous amines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oyenekan, B.A.; Rochelle, G.T.

2007-12-15

Aqueous absorption/stripping is a promising technology for the capture of CO{sub 2} from existing or new coal-fired power plants. Four new stripper configurations (matrix, internal exchange, flashing feed, and multipressure with split feed) have been evaluated with seven model solvents that approximate the thermodynamic and rate properties of 7m (30 wt %) monoethanolamine (MEA), potassium carbonate promoted bypiperazine (PZ), promoted MEA, methyldiethanolamine (MDEA) promoted by PZ, and hindered amines. The results show that solvents with high heats of absorption (MEA, MEA/PZ) favor operation at normal pressure. The relative performance of the alternative configurations is matrix > internal exchange > multipressuremore » with split feed > flashing feed. MEA/PZ and MDEA/PZ are attractive alternatives to 7m MEA. The best solvent and process configuration, matrix with MDEA/PZ, offers 22 and 15% energy savings over the baseline and improved baseline, respectively,with stripping and compression to 10 MPa. The energy requirement for stripping and compression to 10 MPa is about 20% of the power output from a 500 MW power plant with 90% CO{sub 2} removal.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, D.Y.; Hughes, R.W.; Anthony, E.J.

Sintering during calcination/carbonation may introduce substantial economic penalties for a CO{sub 2} looping cycle using limestone/dolomite-derived sorbents. Cyclic carbonation and calcination reactions were investigated for CO{sub 2} capture under fluidized bed combustion (FBC) conditions. The cyclic carbonation characteristics of CaCO{sub 3}-derived sorbents were compared at various calcination temperatures (700-925{sup o} C) and different gas stream compositions: pure -2 and a realistic calciner environment where high concentrations of CO{sub 2}>80-90% are expected. The conditions during carbonation were 700 {sup o}C and 15% CO{sub 2} in N{sub 2} and 0.18% or 0.50% SO{sub 2} in selected tests. Up to 20 calcination/carbonation cyclesmore » were conducted using a thermogravimetric analyzer (TGA) apparatus. Three Canadian limestones were tested: Kelly Rock, Havelock, and Cadomin, using a prescreened particle size range of 400-650 {mu} m. Calcined Kelly Rock and Cadomin samples were hydrated by steam and examined. Sorbent reactivity was reduced whenever SO{sub 2} was introduced to either the calcining or carbonation streams. The multicyclic capture capacity of CaO for CO{sub 2} was substantially reduced at high concentrations of CO{sub 2} during the sorbent regeneration process and carbonation conversion of the Kelly Rock sample obtained after 20 cycles was only 10.5%. Hydrated sorbents performed better for CO{sub 2} capture but showed deterioration following calcination in high CO{sub 2} gas streams indicating that high CO{sub 2} and SO{sub 2} levels in the gas stream lead to lower CaO conversion because of enhanced sintering and irreversible formation of CaSO{sub 4}.« less

β-Na2TeO4: Phase Transition from an Orthorhombic to a Monoclinic Form. Reversible CO2 Capture.

PubMed

Galven, Cyrille; Pagnier, Thierry; Rosman, Noël; Le Berre, Françoise; Crosnier-Lopez, Marie-Pierre

2018-06-18

The present work concerns the tellurate Na 2 TeO 4 which has a 1D structure and could then present a CO 2 capture ability. It has been synthesized in a powder form via a solid-state reaction and structurally characterized by thermal X-ray diffraction experiments, Raman spectroscopy, and differential scanning calorimetry. The room temperature structure corresponds to the β-Na 2 TeO 4 orthorhombic form, and we show that it undergoes a reversible structural transition near 420 °C toward a monoclinic system. Ab initio computations were also performed on the room temperature structure, the Raman vibration modes calculated, and a normal mode attribution proposed. In agreement with our expectations, this sodium oxide is able to trap CO 2 by a two-step mechanism: Na + /H + exchange and carbonation of the released sodium as NaHCO 3 . This capture is reversible since CO 2 can be released upon heating by recombination of the mother phase.

New analytical technique for carbon dioxide absorption solvents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pouryousefi, F.; Idem, R.O.

2008-02-15

The densities and refractive indices of two binary systems (water + MEA and water + MDEA) and three ternary systems (water + MEA + CO{sub 2}, water + MDEA + CO{sub 2}, and water + MEA + MDEA) used for carbon dioxide (CO{sub 2}) capture were measured over the range of compositions of the aqueous alkanolamine(s) used for CO{sub 2} absorption at temperatures from 295 to 338 K. Experimental densities were modeled empirically, while the experimental refractive indices were modeled using well-established models from the known values of their pure-component densities and refractive indices. The density and Gladstone-Dale refractive indexmore » models were then used to obtain the compositions of unknown samples of the binary and ternary systems by simultaneous solution of the density and refractive index equations. The results from this technique have been compared with HPLC (high-performance liquid chromatography) results, while a third independent technique (acid-base titration) was used to verify the results. The results show that the systems' compositions obtained from the simple and easy-to-use refractive index/density technique were very comparable to the expensive and laborious HPLC/titration techniques, suggesting that the refractive index/density technique can be used to replace existing methods for analysis of fresh or nondegraded, CO{sub 2}-loaded, single and mixed alkanolamine solutions.« less

Development Trends in Porous Adsorbents for Carbon Capture.

PubMed

Sreenivasulu, Bolisetty; Sreedhar, Inkollu; Suresh, Pathi; Raghavan, Kondapuram Vijaya

2015-11-03

Accumulation of greenhouse gases especially CO2 in the atmosphere leading to global warming with undesirable climate changes has been a serious global concern. Major power generation in the world is from coal based power plants. Carbon capture through pre- and post- combustion technologies with various technical options like adsorption, absorption, membrane separations, and chemical looping combustion with and without oxygen uncoupling have received considerable attention of researchers, environmentalists and the stake holders. Carbon capture from flue gases can be achieved with micro and meso porous adsorbents. This review covers carbonaceous (organic and metal organic frameworks) and noncarbonaceous (inorganic) porous adsorbents for CO2 adsorption at different process conditions and pore sizes. Focus is also given to noncarbonaceous micro and meso porous adsorbents in chemical looping combustion involving insitu CO2 capture at high temperature (>400 °C). Adsorption mechanisms, material characteristics, and synthesis methods are discussed. Attention is given to isosteric heats and characterization techniques. The options to enhance the techno-economic viability of carbon capture techniques by integrating with CO2 utilization to produce industrially important chemicals like ammonia and urea are analyzed. From the reader's perspective, for different classes of materials, each section has been summarized in the form of tables or figures to get a quick glance of the developments.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, Ba Nghiep; Hou, Zhangshuan; Bacon, Diana H.

This paper applies a multiscale hydro-geochemical-mechanical approach to analyze faulted CO 2 reservoirs using the STOMP-CO 2-R code that is coupled to the ABAQUS® finite element package. STOMP-CO 2-R models the reactive transport of CO 2 causing mineral volume fraction changes that are captured by an Eshelby-Mori-Tanka model implemented in ABAQUS®. A three-dimensional (3D) STOMP-CO 2-R model for a reservoir containing an inclined fault was built to analyze a formation containing a reaction network with 5 minerals: albite, anorthite, calcite, kaolinite and quartz. A 3D finite element mesh that exactly maps the STOMP-CO 2-R grid is developed for coupled hydro-geochemical-mechanicalmore » analyses. The model contains alternating sandstone and shale layers. The impact of reactive transport of CO 2 on the geomechanical properties of reservoir rocks and seals are studied in terms of mineral composition changes that affect their geomechanical responses. Simulations assuming extensional and compressional stress regimes with and without coupled geochemistry are performed to study the stress regime effect on the risk of hydraulic fracture. The tendency for the fault to slip is examined in terms of stress regime, geomechanical and geochemical-mechanical effects as well as fault inclination. The results show that mineralogical changes due to long-term injection of CO 2 reduce the permeability and elastic modulus of the reservoir, leading to increased risk of hydraulic fracture in the injection location and at the caprock seal immediately above the injection zone. Fault slip is not predicted to occur. However, fault inclination and stress regime have an important impact on the slip tendency factor.« less

Robust CO2 Injection: Application of Bayesian-Information-Gap Decision Theory

NASA Astrophysics Data System (ADS)

Grasinger, M.; O'Malley, D.; Vesselinov, V. V.; Karra, S.

2015-12-01

Carbon capture and sequestration has the potential to reduce greenhouse gasemissions. However, care must be taken when choosing a site for CO2 seques-tration to ensure that the CO2 remains sequestered for many years, and thatthe environment is not harmed in any way. Making a rational decision be-tween potential sites for sequestration is not without its challenges because, asin the case of many environmental and subsurface problems, there is a lot ofuncertainty that exists. A method for making decisions under various typesand severities of uncertainty, Bayesian-Information-Gap Decision Theory (BIGDT), is presented. BIG DT was coupled with a numerical model for CO2 wellinjection and the resulting framework was then applied to a problem of selectingbetween two potential sites for CO2 sequestration. The results of the analysisare presented, followed by a discussion of the decision process.

Toward rational design of amines for CO2 capture: Substituent effect on kinetic process for the reaction of monoethanolamine with CO2.

PubMed

Xie, Hongbin; Wang, Pan; He, Ning; Yang, Xianhai; Chen, Jingwen

2015-11-01

Amines have been considered as promising candidates for post-combustion CO2 capture. A mechanistic understanding for the chemical processes involved in the capture and release of CO2 is important for the rational design of amines. In this study, the structural effects of amines on the kinetic competition among three typical products (carbamates, carbamic acids and bicarbonate) from amines+CO2 were investigated, in contrast to previous thermodynamic studies to tune the reaction of amines with CO2 based on desirable reaction enthalpy and reaction stoichiometry. We used a quantum chemical method to calculate the activation energies (Ea) for the reactions of a range of substituted monoethanolamines with CO2 covering three pathways to the three products. The results indicate that the formation of carbamates is the most favorable, among the three considered products. In addition, we found that the Ea values for all pathways linearly correlate with pKa of amines, and more importantly, the kinetic competition between carbamate and bicarbonate absorption pathways varies with pKa of the amines, i.e. stronger basicity results in less difference in Ea. These results highlight the importance of the consideration of kinetic competition among different reaction pathways in amine design. Copyright © 2015. Published by Elsevier B.V.

Optimal distribution of borehole geophones for monitoring CO2-injection-induced seismicity

NASA Astrophysics Data System (ADS)

Huang, L.; Chen, T.; Foxall, W.; Wagoner, J. L.

2016-12-01

The U.S. DOE initiative, National Risk Assessment Partnership (NRAP), aims to develop quantitative risk assessment methodologies for carbon capture, utilization and storage (CCUS). As part of tasks of the Strategic Monitoring Group of NRAP, we develop a tool for optimal design of a borehole geophones distribution for monitoring CO2-injection-induced seismicity. The tool consists of a number of steps, including building a geophysical model for a given CO2 injection site, defining target monitoring regions within CO2-injection/migration zones, generating synthetic seismic data, giving acceptable uncertainties in input data, and determining the optimal distribution of borehole geophones. We use a synthetic geophysical model as an example to demonstrate the capability our new tool to design an optimal/cost-effective passive seismic monitoring network using borehole geophones. The model is built based on the geologic features found at the Kimberlina CCUS pilot site located in southern San Joaquin Valley, California. This tool can provide CCUS operators with a guideline for cost-effective microseismic monitoring of geologic carbon storage and utilization.

Biomimetic CO2 capture using a highly thermostable bacterial α-carbonic anhydrase immobilized on a polyurethane foam.

PubMed

Migliardini, Fortunato; De Luca, Viviana; Carginale, Vincenzo; Rossi, Mosè; Corbo, Pasquale; Supuran, Claudiu T; Capasso, Clemente

2014-02-01

The biomimetic approach represents an interesting strategy for carbon dioxide (CO2) capture, offering advantages over other methods, due to its specificity for CO2 and its eco-compatibility, as it allows concentration of CO2 from other gases, and its conversion to water soluble ions. This approach uses microorganisms capable of fixing CO2 through metabolic pathways or via the use of an enzyme, such as carbonic anhydrase (CA, EC 4.2.1.1). Recently, our group cloned and purified a novel bacterial α-CA, named SspCA, from the thermophilic bacteria, Sulfurihydrogenibium yellowstonense YO3AOP1 living in hot springs at temperatures of up to 110 °C. This enzyme showed an exceptional thermal stability, retaining its high catalytic activity for the CO2 hydration reaction even after being heated at 70 °C for several hours. In the present paper, the SspCA was immobilized within a polyurethane (PU) foam. The immobilized enzyme was found to be catalytically active and showed a long-term stability. A bioreactor containing the "PU-immobilized enzyme" (PU-SspCA) as shredded foam was used for experimental tests aimed to verify the CO2 capture capability in conditions close to those of a power plant application. In this bioreactor, a gas phase, containing CO2, was put into contact with a liquid phase under conditions, where CO2 contained in the gas phase was absorbed and efficiently converted into bicarbonate by the extremo-α-CA.

Synthesis of highly efficient CaO-based, self-stabilizing CO2 sorbents via structure-reforming of steel slag.

PubMed

Tian, Sicong; Jiang, Jianguo; Yan, Feng; Li, Kaimin; Chen, Xuejing

2015-06-16

Capturing anthropogenic CO2 in a cost-effective and highly efficient manner is one of the most challenging issues faced by scientists today. Herein, we report a novel structure-reforming approach to convert steel slag, a cheap, abundant, and nontoxic calcium-rich industrial waste, as the only feedstock into superior CaO-based, self-stabilizing CO2 sorbents. The CO2 capture capacity of all the steel slag-derived sorbents was improved more than 10-fold compared to the raw slag, with the maximum uptake of CO2 achieving at 0.50 gCO2 gsorbent(-1). Additionally, the initial steel slag-derived sorbent could retain 0.25 gCO2 gsorbent(-1), that is, a decay rate of only 12% over 30 carbonation-calcination cycles, the excellent self-stabilizing property allowed it to significantly outperform conventional CaO, and match with most of the existing synthetic CaO-based sorbents. A synergistic effect that facilitated CO2 capture by CaO-based sorbents was clearly recognized when Mg and Al, the most common elements in steel slag, coexisted with CaO in the forms of MgO and Al2O3, respectively. During the calcium looping process, MgO served as a well spacer to increase the porosity of sorbents together with Al2O3 serving as a durable stabilizer to coresist the sintering of CaCO3 grains at high temperatures.

Anion-Functionalized Task-Specific Ionic Liquids: Molecular Origin of Change in Viscosity upon CO2 Capture.

PubMed

Li, Ailin; Tian, Ziqi; Yan, Tianying; Jiang, De-en; Dai, Sheng

2014-12-26

The structure and dynamics of a task-specific ionic liquid (TSIL), trihexyl(tetradecyl)phosphonium imidazolate, before and after absorbing CO(2) were studied with a molecular dynamics (MD) simulation. This particular ionic liquid is one of several newly discovered azole-based TSILs for equimolar CO(2) capture. Unlike other TSILs whose viscosity increases drastically upon reaction with CO(2), its viscosity decreases after CO(2) absorption. This unique behavior was confirmed in our MD simulation. We find that after CO(2) absorption the translational dynamics of the whole system is accelerated, accompanied by an accelerated rotational dynamics of the cations. Radial distribution function and spatial distribution function analyses show that the anions become asymmetric after reaction with CO(2), and this causes the imbalance of the interaction between the positive and negative regions of the ions. The interaction between the phosphorus atom of the cation and oxygen atoms of the carboxyl group on the anion is enhanced, while that between the phosphorus atom and the naked nitrogen atom of the anion is weakened. The ion-pair correlation functions further support that the weakened interaction leads to faster dissociation of cation-anion pairs, thereby causing an accelerated dynamics. Hence, the asymmetry of anions influences the dynamics of the system and affects the viscosity. This insight may help design better TSILs with decreased viscosity for CO(2) capture.

Ecosystem CO2 Exchange Across Semiarid Southwestern North America: A Synthesis of Multi-Year Flux Site Observations and its Comparison with Estimates from Terrestrial Biome Models and Remote Sensing

NASA Astrophysics Data System (ADS)

Biederman, J. A.; Scott, R. L.; Goulden, M.; Litvak, M. E.; Kolb, T.; Yepez, E. A.; Garatuza, J.; Oechel, W. C.; Krofcheck, D. J.; Ponce-Campos, G. E.; Bowling, D. R.; Meyers, T. P.; Maurer, G.

2016-12-01

Global carbon cycle studies reveal that semiarid ecosystems dominate the increasing trend and interannual variability of the land CO2 sink. However, the regional terrestrial biome models (TBM) and remote sensing products (RSP) used in large-scale analyses are poorly constrained by ecosystem flux measurements in semiarid regions, which are under-represented in global flux datasets. Here we present eddy covariance measurements from 25 diverse ecosystems in semiarid southwestern North America with ranges in annual precipitation of 100 - 1000 mm, annual temperatures of 2 - 25 °C, and records of 3 - 10 years each (150 site-years in total). We identified seven subregions with unique seasonal dynamics in climate and ecosystem-atmosphere exchange, including net and gross CO2 exchange (photosynthesis and respiration) and evapotranspiration (ET), and we evaluated how well measured dynamics were captured by satellite-based greenness observations of the Enhanced Vegetation Index (EVI). Annual flux integrals were calculated based on site-appropriate ecohydrologic years. Net ecosystem production (NEP) varied between -550 and + 420 g C m-2, highlighting the wide range of regional sink/source function. Annual photosynthesis and respiration were positively related to water availability but were suppressed in warmer years at a given site and at climatically warmer sites, in contrast to positive temperature responses at wetter sites. When precipitation anomalies were spatially coherent across sites (e.g. related to El Niño Southern Oscillation), we found large regional annual anomalies in net and gross CO2 uptake. TBM and RSP were less effective in capturing spatial gradients in mean ET and CO2 exchange across this semiarid region as compared to wetter regions. Measured interannual variability of ET and gross CO2 exchange was 3 - 5 times larger than estimates from TBM or RSP. These results suggest that semiarid regions play an even larger role in regulating interannual variability of the global carbon cycle than currently estimated by models and remote sensing. In on-going work, we expand this spatial-temporal analysis across a broader gradient of water availability using the Fluxnet 2015 dataset.

About how to capture and exploit the CO2 surplus that nature, per se, is not capable of fixing.

PubMed

Godoy, Manuel S; Mongili, Beatrice; Fino, Debora; Prieto, M Auxiliadora

2017-09-01

Human activity has been altering many ecological cycles for decades, disturbing the natural mechanisms which are responsible for re-establishing the normal environmental balances. Probably, the most disrupted of these cycles is the cycle of carbon. In this context, many technologies have been developed for an efficient CO 2 removal from the atmosphere. Once captured, it could be stored in large geological formations and other reservoirs like oceans. This strategy could present some environmental and economic problems. Alternately, CO 2 can be transformed into carbonates or different added-value products, such as biofuels and bioplastics, recycling CO 2 from fossil fuel. Currently different methods are being studied in this field. We classified them into biological, inorganic and hybrid systems for CO 2 transformation. To be environmentally compatible, they should be powered by renewable energy sources. Although hybrid systems are still incipient technologies, they have made great advances in the recent years. In this scenario, biotechnology is the spearhead of ambitious strategies to capture CO 2 and reduce global warming. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Understanding of Electrochemical Mechanisms for CO2 Capture and Conversion into Hydrocarbon Fuels in Transition-Metal Carbides (MXenes).

PubMed

Li, Neng; Chen, Xingzhu; Ong, Wee-Jun; MacFarlane, Douglas R; Zhao, Xiujian; Cheetham, Anthony K; Sun, Chenghua

2017-11-28

Two-dimensional (2D) transition-metal (groups IV, V, VI) carbides (MXenes) with formulas M 3 C 2 have been investigated as CO 2 conversion catalysts with well-resolved density functional theory calculations. While MXenes from the group IV to VI series have demonstrated an active behavior for the capture of CO 2 , the Cr 3 C 2 and Mo 3 C 2 MXenes exhibit the most promising CO 2 to CH 4 selective conversion capabilities. Our results predicted the formation of OCHO • and HOCO • radical species in the early hydrogenation steps through spontaneous reactions. This provides atomic level insights into the computer-aided screening for high-performance catalysts and the understanding of electrochemical mechanisms for CO 2 reduction to energy-rich hydrocarbon fuels, which is of fundamental significance to elucidate the elementary steps for CO 2 fixation.

Leaf fossil record suggests limited influence of atmospheric CO2 on terrestrial productivity prior to angiosperm evolution

PubMed Central

Boyce, C. Kevin; Zwieniecki, Maciej A.

2012-01-01

Declining CO2 over the Cretaceous has been suggested as an evolutionary driver of the high leaf vein densities (7–28 mm mm−2) that are unique to the angiosperms throughout all of Earth history. Photosynthetic modeling indicated the link between high vein density and productivity documented in the modern low-CO2 regime would be lost as CO2 concentrations increased but also implied that plants with very low vein densities (less than 3 mm mm−2) should experience substantial disadvantages with high CO2. Thus, the hypothesized relationship between CO2 and plant evolution can be tested through analysis of the concurrent histories of alternative lineages, because an extrinsic driver like atmospheric CO2 should affect all plants and not just the flowering plants. No such relationship is seen. Regardless of CO2 concentrations, low vein densities are equally common among nonangiosperms throughout history and common enough to include forest canopies and not just obligate shade species that will always be of limited productivity. Modeling results can be reconciled with the fossil record if maximum assimilation rates of nonflowering plants are capped well below those of flowering plants, capturing biochemical and physiological differences that would be consistent with extant plants but previously unrecognized in the fossil record. Although previous photosynthetic modeling suggested that productivity would double or triple with each Phanerozoic transition from low to high CO2, productivity changes are likely to have been limited before a substantial increase accompanying the evolution of flowering plants. PMID:22689947

Techno-economic analysis of sorption-enhanced steam methane reforming in a fixed bed reactor network integrated with fuel cell

NASA Astrophysics Data System (ADS)

Diglio, Giuseppe; Hanak, Dawid P.; Bareschino, Piero; Mancusi, Erasmo; Pepe, Francesco; Montagnaro, Fabio; Manovic, Vasilije

2017-10-01

Sorption-enhanced steam methane reforming (SE-SMR) is a promising alternative for H2 production with inherent CO2 capture. This study evaluates the techno-economic performance of SE-SMR in a network of fixed beds and its integration with a solid oxide fuel cell (SE-SMR-SOFC) for power generation. The analysis revealed that both proposed systems are characterised by better economic performance than the reference systems. In particular, for SE-SMR the levelised cost of hydrogen is 1.6 €ṡkg-1 and the cost of CO2 avoided is 29.9 €ṡtCO2-1 (2.4 €ṡkg-1 and 50 €ṡtCO2-1, respectively, for SMR with CO2 capture) while for SE-SMR-SOFC the levelised cost of electricity is 0.078 €ṡkWh-1 and the cost of CO2 avoided is 36.9 €ṡtCO2-1 (0.080 €ṡkWh-1 and 80 €ṡtCO2-1, respectively, for natural gas-fired power plant with carbon capture). The sensitivity analysis showed that the specific cost of fuel and the capital cost of fuel cell mainly affect the economic performance of SE-SMR and SE-SMR-SOFC, respectively. The daily revenue of the SE-SMR-SOFC system is higher than that of the natural gas-fired power plant if the difference between the carbon tax and the CO2 transport and storage cost is > 6 €ṡtCO2-1.

Efficiency enhancement for natural gas liquefaction with CO2 capture and sequestration through cycles innovation and process optimization

NASA Astrophysics Data System (ADS)

Alabdulkarem, Abdullah

Liquefied natural gas (LNG) plants are energy intensive. As a result, the power plants operating these LNG plants emit high amounts of CO2 . To mitigate global warming that is caused by the increase in atmospheric CO2, CO2 capture and sequestration (CCS) using amine absorption is proposed. However, the major challenge of implementing this CCS system is the associated power requirement, increasing power consumption by about 15--25%. Therefore, the main scope of this work is to tackle this challenge by minimizing CCS power consumption as well as that of the entire LNG plant though system integration and rigorous optimization. The power consumption of the LNG plant was reduced through improving the process of liquefaction itself. In this work, a genetic algorithm (GA) was used to optimize a propane pre-cooled mixed-refrigerant (C3-MR) LNG plant modeled using HYSYS software. An optimization platform coupling Matlab with HYSYS was developed. New refrigerant mixtures were found, with savings in power consumption as high as 13%. LNG plants optimization with variable natural gas feed compositions was addressed and the solution was proposed through applying robust optimization techniques, resulting in a robust refrigerant which can liquefy a range of natural gas feeds. The second approach for reducing the power consumption is through process integration and waste heat utilization in the integrated CCS system. Four waste heat sources and six potential uses were uncovered and evaluated using HYSYS software. The developed models were verified against experimental data from the literature with good agreement. Net available power enhancement in one of the proposed CCS configuration is 16% more than the conventional CCS configuration. To reduce the CO2 pressurization power into a well for enhanced oil recovery (EOR) applications, five CO2 pressurization methods were explored. New CO2 liquefaction cycles were developed and modeled using HYSYS software. One of the developed liquefaction cycles using NH3 as a refrigerant resulted in 5% less power consumption than the conventional multi-stage compression cycle. Finally, a new concept of providing the CO2 regeneration heat is proposed. The proposed concept is using a heat pump to provide the regeneration heat as well as process heat and CO2 liquefaction heat. Seven configurations of heat pumps integrated with CCS were developed. One of the heat pumps consumes 24% less power than the conventional system or 59% less total equivalent power demand than the conventional system with steam extraction and CO2 compression.

Accelerated carbonation using municipal solid waste incinerator bottom ash and cold-rolling wastewater: Performance evaluation and reaction kinetics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, E-E; Pan, Shu-Yuan; Yang, Liuhanzi

2015-09-15

Highlights: • Carbonation was performed using CO{sub 2}, wastewater and bottom ash in a slurry reactor. • A maximum capture capacity of 102 g CO{sub 2} per kg BA was achieved at mild conditions. • A maximum carbonation conversion of MSWI-BA was predicted to be 95% by RSM. • The CO{sub 2} emission from Bali incinerator could be expected to reduce by 6480 ton/y. • The process energy consumption per ton CO{sub 2} captured was estimated to be 180 kW h. - Abstract: Accelerated carbonation of alkaline wastes including municipal solid waste incinerator bottom ash (MSWI-BA) and the cold-rolling wastewatermore » (CRW) was investigated for carbon dioxide (CO{sub 2}) fixation under different operating conditions, i.e., reaction time, CO{sub 2} concentration, liquid-to-solid ratio, particle size, and CO{sub 2} flow rate. The MSWI-BA before and after carbonation process were analyzed by the thermogravimetry and differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy equipped with energy dispersive X-ray spectroscopy. The MSWI-BA exhibits a high carbonation conversion of 90.7%, corresponding to a CO{sub 2} fixation capacity of 102 g per kg of ash. Meanwhile, the carbonation kinetics was evaluated by the shrinking core model. In addition, the effect of different operating parameters on carbonation conversion of MSWI-BA was statistically evaluated by response surface methodology (RSM) using experimental data to predict the maximum carbonation conversion. Furthermore, the amount of CO{sub 2} reduction and energy consumption for operating the proposed process in refuse incinerator were estimated. Capsule abstract: CO{sub 2} fixation process by alkaline wastes including bottom ash and cold-rolling wastewater was developed, which should be a viable method due to high conversion.« less

Important roles of enthalpic and entropic contributions to CO2 capture from simulated flue gas and ambient air using mesoporous silica grafted amines.

PubMed

Alkhabbaz, Mustafa A; Bollini, Praveen; Foo, Guo Shiou; Sievers, Carsten; Jones, Christopher W

2014-09-24

The measurement of isosteric heats of adsorption of silica supported amine materials in the low pressure range (0-0.1 bar) is critical for understanding the interactions between CO2 and amine sites at low coverage and hence to the development of efficient amine adsorbents for CO2 capture from flue gas and ambient air. Heats of adsorption for an array of silica-supported amine materials are experimentally measured at low coverage using a Calvet calorimeter equipped with a customized dosing manifold. In a series of 3-aminopropyl-functionalized silica materials, higher amine densities resulted in higher isosteric heats of adsorption, clearly showing that the density/proximity of amine sites can influence the amine efficiency of adsorbents. In a series of materials with fixed amine loading but different amine types, strongly basic primary and secondary amine materials are shown to have essentially identical heats of adsorption near 90 kJ/mol. However, the adsorption uptakes vary substantially as a function of CO2 partial pressure for different primary and secondary amines, demonstrating that entropic contributions to adsorption may play a key role in adsorption at secondary amine sites, making adsorption at these sites less efficient at the low coverages that are important to the direct capture of CO2 from ambient air. Thus, while primary amines are confirmed to be the most effective amine types for CO2 capture from ambient air, this is not due to enhanced enthalpic contributions associated with primary amines over secondary amines, but may be due to unfavorable entropic factors associated with organization of the second alkyl chain on the secondary amine during CO2 adsorption. Given this hypothesis, favorable entropic factors may be the main reason primary amine based adsorbents are more effective under air capture conditions.

Relationship between mosquito (Diptera: Culicidae) landing rates on a human subject and numbers captured using CO2-baited light traps.

PubMed

Barnard, D R; Knue, G J; Dickerson, C Z; Bernier, U R; Kline, D L

2011-06-01

Capture rates of insectary-reared female Aedes albopictus (Skuse), Anopheles quadrimaculatus Say, Culex nigripalpus Theobald, Culex quinquefasciatus Say and Aedes triseriatus (Say) in CDC-type light traps (LT) supplemented with CO2 and using the human landing (HL) collection method were observed in matched-pair experiments in outdoor screened enclosures. Mosquito responses were compared on a catch-per-unit-effort basis using regression analysis with LT and HL as the dependent and independent variables, respectively. The average number of mosquitoes captured in 1 min by LT over a 24-h period was significantly related to the average number captured in 1 min by HL only for Cx. nigripalpus and Cx. quinquefasciatus. Patterns of diel activity indicated by a comparison of the mean response to LT and HL at eight different times in a 24-h period were not superposable for any species. The capture rate efficiency of LT when compared with HL was ≤15% for all mosquitoes except Cx. quinquefasciatus (43%). Statistical models of the relationship between mosquito responses to each collection method indicate that, except for Ae. albopictus, LT and HL capture rates are significantly related only during certain times of the diel period. Estimates of mosquito activity based on observations made between sunset and sunrise were most precise in this regard for An. quadrimaculatus and Cx. nigripalpus, as were those between sunrise and sunset for Cx. quinquefasciatus and Ae. triseriatus.

Insights into the mechanism of the capture of CO2 by K2CO3 sorbent: a DFT study.

PubMed

Liu, Hongyan; Qin, Qiaoyun; Zhang, Riguang; Ling, Lixia; Wang, Baojun

2017-09-13

The adsorption and reactions of CO 2 and H 2 O on both monoclinic and hexagonal crystal K 2 CO 3 were investigated using the density functional theory (DFT) approach. The calculated adsorption energies showed that adsorption of H 2 O molecules was clearly substantially stronger on the K 2 CO 3 surface than the adsorption of CO 2 , except on the (001)-1 surface of hexagonal K 2 CO 3 , where CO 2 is competitively adsorbed with H 2 O. Carbonation reactions easily occur on pure K 2 CO 3 and involve two parallel paths: one is where adsorbed H 2 O reacts with molecular CO 2 in gas to form the bicarbonate, while the other is where H 2 O dissociates into OH and H before bicarbonate formation, and then OH reacts with gaseous CO 2 to form a bicarbonate. Our results indicate that adding a support or promoter or using a special technique to expose more (001)-1 surfaces in hexagonal K 2 CO 3 may improve the conversion of CO 2 to the bicarbonate, which provides a theoretical direction for the experimental preparation of the K 2 CO 3 sorbent to capture CO 2 .

Modeling Global Atmospheric CO2 Fluxes and Transport Using NASA MERRA Reanalysis Data

NASA Astrophysics Data System (ADS)

Liu, Y.; Kawa, S. R.; Collatz, G. J.

2010-12-01

We present our first results of CO2 surface biosphere fluxes and global atmospheric CO2 transport using NASA’s new MERRA reanalysis data. MERRA is the Modern Era Retrospective-Analysis For Research And Applications based on the Goddard Global Modeling and Assimilation Office GEOS-5 data assimilation system. After some application testing and analysis, we have generated biospheric CO2 fluxes at 3-hourly temporal resolution from an updated version of the CASA carbon cycle model using the 1x1.25-degree reanalysis data. The experiment covers a period of 9 years from 2000 -2008. The affects of US midwest crop (largely corn and soy) carbon uptake and removal by harvest are explicitly included in this version of CASA. Across the agricultural regions of the Midwest US, USDA crop yield data are used to scale vegetation fluxes producing a strong sink in the growing season and a comparatively weaker source from respiration after harvest. Comparisons of the new fluxes to previous ones generated using GEOS-4 data are provided. The Parameterized Chemistry/Transport Model (PCTM) is then used with the analyzed meteorology in offline CO2 transport. In the simulation of CO2 transport, we have a higher vertical resolution from MERRA (the lowest 56 of 72 levels are used in our simulation). A preliminary analysis of the CO2 simulation results is carried out, including diurnal, seasonal and latitudinal variability. We make comparisons of our simulation to continuous CO2 analyzer sites, especially those in agricultural regions. The results show that the model captures reasonably well the observed synoptic variability due to transport changes and biospheric fluxes.

Prediction of heat capacity of amine solutions using artificial neural network and thermodynamic models for CO2 capture processes

NASA Astrophysics Data System (ADS)

Afkhamipour, Morteza; Mofarahi, Masoud; Borhani, Tohid Nejad Ghaffar; Zanganeh, Masoud

2018-03-01

In this study, artificial neural network (ANN) and thermodynamic models were developed for prediction of the heat capacity ( C P ) of amine-based solvents. For ANN model, independent variables such as concentration, temperature, molecular weight and CO2 loading of amine were selected as the inputs of the model. The significance of the input variables of the ANN model on the C P values was investigated statistically by analyzing of correlation matrix. A thermodynamic model based on the Redlich-Kister equation was used to correlate the excess molar heat capacity ({C}_P^E) data as function of temperature. In addition, the effects of temperature and CO2 loading at different concentrations of conventional amines on the C P values were investigated. Both models were validated against experimental data and very good results were obtained between two mentioned models and experimental data of C P collected from various literatures. The AARD between ANN model results and experimental data of C P for 47 systems of amine-based solvents studied was 4.3%. For conventional amines, the AARD for ANN model and thermodynamic model in comparison with experimental data were 0.59% and 0.57%, respectively. The results showed that both ANN and Redlich-Kister models can be used as a practical tool for simulation and designing of CO2 removal processes by using amine solutions.

Relationship between mosquito (Diptera: Culicidae) landing rates on a human subject and numbers captured using CO2-baited light traps

USDA-ARS?s Scientific Manuscript database

Capture rates of female Aedes albopictus Skuse, Aedes triseriatus (Say), Anopheles quadrimaculatus Say, Culex nigripalpus Theobald, and Culex quinquefasciatus Say in CDC-type light traps supplemented with CO2 (LT) and using the human landing (HL) collection method were observed in matched-pair exper...

Designing and Demonstrating a Master Student Project to Explore Carbon Dioxide Capture Technology

ERIC Educational Resources Information Center

Asherman, Florine; Cabot, Gilles; Crua, Cyril; Estel, Lionel; Gagnepain, Charlotte; Lecerf, Thibault; Ledoux, Alain; Leveneur, Sebastien; Lucereau, Marie; Maucorps, Sarah; Ragot, Melanie; Syrykh, Julie; Vige, Manon

2016-01-01

The rise in carbon dioxide (CO[subscript 2]) concentration in the Earth's atmosphere, and the associated strengthening of the greenhouse effect, requires the development of low carbon technologies. New carbon capture processes are being developed to remove CO[subscript 2] that would otherwise be emitted from industrial processes and fossil fuel…

Membrane contactors for CO2 capture processes - critical review

NASA Astrophysics Data System (ADS)

Nogalska, Adrianna; Trojanowska, Anna; Garcia-Valls, Ricard

2017-07-01

The use of membrane contactor in industrial processes is wide, and lately it started to be used in CO2 capture process mainly for gas purification or to reduce the emission. Use of the membrane contactor provides high contact surface area so the size of the absorber unit significantly decreases, which is an important factor for commercialization. The research has been caried out regarding the use of novel materials for the membrane production and absorbent solution improvements. The present review reveals the progress in membrane contactor systems for CO2 capture processes concerning solution for ceramic membrane wetting, comparison study of different polymers used for fabrication and methods of enzyme immobilization for biocomposite membrane. Also information about variety of absorbent solutions is described.