40 CFR 63.3554 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
... system efficiency? 63.3554 Section 63.3554 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Requirements for the Control Efficiency/outlet Concentration Option § 63.3554 How do I determine the emission capture system efficiency? The capture efficiency of your emission capture system must be 100 percent to...
40 CFR 63.3554 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
... system efficiency? 63.3554 Section 63.3554 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Requirements for the Control Efficiency/outlet Concentration Option § 63.3554 How do I determine the emission capture system efficiency? The capture efficiency of your emission capture system must be 100 percent to...
Code of Federal Regulations, 2014 CFR
2014-07-01
... to capture emissions; (3) If a mobile scrubber car that does not capture emissions during travel is... each capture system that uses an electric motor to drive the fan, you must maintain the daily average... (ii) For each capture system that does not use a fan driven by an electric motor, you must maintain...
Code of Federal Regulations, 2013 CFR
2013-07-01
... to capture emissions; (3) If a mobile scrubber car that does not capture emissions during travel is... each capture system that uses an electric motor to drive the fan, you must maintain the daily average... (ii) For each capture system that does not use a fan driven by an electric motor, you must maintain...
Code of Federal Regulations, 2012 CFR
2012-07-01
... to capture emissions; (3) If a mobile scrubber car that does not capture emissions during travel is... each capture system that uses an electric motor to drive the fan, you must maintain the daily average... (ii) For each capture system that does not use a fan driven by an electric motor, you must maintain...
Code of Federal Regulations, 2011 CFR
2011-07-01
... to capture emissions; (3) If a mobile scrubber car that does not capture emissions during travel is... each capture system that uses an electric motor to drive the fan, you must maintain the daily average... (ii) For each capture system that does not use a fan driven by an electric motor, you must maintain...
Code of Federal Regulations, 2010 CFR
2010-07-01
... to capture emissions; (3) If a mobile scrubber car that does not capture emissions during travel is... each capture system that uses an electric motor to drive the fan, you must maintain the daily average... (ii) For each capture system that does not use a fan driven by an electric motor, you must maintain...
Bogolon-mediated electron capture by impurities in hybrid Bose-Fermi systems
NASA Astrophysics Data System (ADS)
Boev, M. V.; Kovalev, V. M.; Savenko, I. G.
2018-04-01
We investigate the processes of electron capture by a Coulomb impurity center residing in a hybrid system consisting of spatially separated two-dimensional layers of electron and Bose-condensed dipolar exciton gases coupled via the Coulomb forces. We calculate the probability of the electron capture accompanied by the emission of a single Bogoliubov excitation (bogolon), similar to regular phonon-mediated scattering in solids. Furthermore, we study the electron capture mediated by the emission of a pair of bogolons in a single capture event and show that these processes not only should be treated in the same order of the perturbation theory, but also they give a more important contribution than single-bogolon-mediated capture, in contrast with regular phonon scattering.
Last chance for carbon capture and storage
NASA Astrophysics Data System (ADS)
Scott, Vivian; Gilfillan, Stuart; Markusson, Nils; Chalmers, Hannah; Haszeldine, R. Stuart
2013-02-01
Anthropogenic energy-related CO2 emissions are higher than ever. With new fossil-fuel power plants, growing energy-intensive industries and new sources of fossil fuels in development, further emissions increase seems inevitable. The rapid application of carbon capture and storage is a much heralded means to tackle emissions from both existing and future sources. However, despite extensive and successful research and development, progress in deploying carbon capture and storage has stalled. No fossil-fuel power plants, the greatest source of CO2 emissions, are using carbon capture and storage, and publicly supported demonstration programmes are struggling to deliver actual projects. Yet, carbon capture and storage remains a core component of national and global emissions-reduction scenarios. Governments have to either increase commitment to carbon capture and storage through much more active market support and emissions regulation, or accept its failure and recognize that continued expansion of power generation from burning fossil fuels is a severe threat to attaining objectives in mitigating climate change.
Code of Federal Regulations, 2013 CFR
2013-07-01
... system and add-on control device operating limits during the performance test? 63.4966 Section 63.4966... outlet gas temperature is the maximum operating limit for your condenser. (e) Emission capture system... Emission Rate with Add-on Controls Option § 63.4966 How do I establish the emission capture system and add...
Capture and Emission of Charge Carriers by Quantum Well
NASA Astrophysics Data System (ADS)
Davydov, V. N.; Karankevich, O. A.
2018-06-01
The interaction of electrons from the conduction band of the barrier layer of a LED heterostructure with the quantum well size-quantization level described by the capture time and emission time of charge carriers is considered. Relaxation of an excess energy upon capture and emission of charge carriers occurs as a result of their collisions with phonons of the quantum well substance and the "barrier layer-quantum well" interface. Analytical expressions are obtained for the interaction times, taking into account the depth of the sizequantization level, involved in the interaction with electrons, and the width of the well. Numerical estimates show that in real conditions, the capture time is shorter than the emission time, and this difference increases with increasing depth of the level. At shallow depths, the capture and emission times are comparable.
Zhai, Haibo; Ou, Yang; Rubin, Edward S
2015-07-07
This study employs a power plant modeling tool to explore the feasibility of reducing unit-level emission rates of CO2 by 30% by retrofitting carbon capture, utilization, and storage (CCUS) to existing U.S. coal-fired electric generating units (EGUs). Our goal is to identify feasible EGUs and their key attributes. The results indicate that for about 60 gigawatts of the existing coal-fired capacity, the implementation of partial CO2 capture appears feasible, though its cost is highly dependent on the unit characteristics and fuel prices. Auxiliary gas-fired boilers can be employed to power a carbon capture process without significant increases in the cost of electricity generation. A complementary CO2 emission trading program can provide additional economic incentives for the deployment of CCS with 90% CO2 capture. Selling and utilizing the captured CO2 product for enhanced oil recovery can further accelerate CCUS deployment and also help reinforce a CO2 emission trading market. These efforts would allow existing coal-fired EGUs to continue to provide a significant share of the U.S. electricity demand.
Eddingsaas, Nathan; Pagano, Todd; Cummings, Cody; Rahman, Irfan; Robinson, Risa; Hensel, Edward
2018-02-13
This work investigates emissions sampling methods employed for qualitative identification of compounds in e-liquids and their resultant aerosols to assess what capture methods may be sufficient to identify harmful and potentially harmful constituents present. Three popular e-liquid flavors (cinnamon, mango, vanilla) were analyzed using qualitative gas chromatography-mass spectrometry (GC-MS) in the un-puffed state. Each liquid was also machine-puffed under realistic-use flow rate conditions and emissions were captured using two techniques: filter pads and methanol impingers. GC-MS analysis was conducted on the emissions captured using both techniques from all three e-liquids. The e-liquid GC-MS analysis resulted in positive identification of 13 compounds from the cinnamon flavor e-liquid, 31 from mango, and 19 from vanilla, including a number of compounds observed in all e-liquid experiments. Nineteen compounds were observed in emissions which were not present in the un-puffed e-liquid. Qualitative GC-MS analysis of the emissions samples identify compounds observed in all three samples: e-liquid, impinge, and filter pads, and each subset thereof. A limited number of compounds were observed in emissions captured with impingers, but were not observed in emissions captured using filter pads; a larger number of compounds were observed on emissions collected from the filter pads, but not those captured with impingers. It is demonstrated that sampling methods have different sampling efficiencies and some compounds might be missed using only one method. It is recommended to investigate filter pads, impingers, thermal desorption tubes, and solvent extraction resins to establish robust sampling methods for emissions testing of e-cigarette emissions.
Eddingsaas, Nathan; Pagano, Todd; Cummings, Cody; Rahman, Irfan; Robinson, Risa
2018-01-01
This work investigates emissions sampling methods employed for qualitative identification of compounds in e-liquids and their resultant aerosols to assess what capture methods may be sufficient to identify harmful and potentially harmful constituents present. Three popular e-liquid flavors (cinnamon, mango, vanilla) were analyzed using qualitative gas chromatography-mass spectrometry (GC-MS) in the un-puffed state. Each liquid was also machine-puffed under realistic-use flow rate conditions and emissions were captured using two techniques: filter pads and methanol impingers. GC-MS analysis was conducted on the emissions captured using both techniques from all three e-liquids. The e-liquid GC-MS analysis resulted in positive identification of 13 compounds from the cinnamon flavor e-liquid, 31 from mango, and 19 from vanilla, including a number of compounds observed in all e-liquid experiments. Nineteen compounds were observed in emissions which were not present in the un-puffed e-liquid. Qualitative GC-MS analysis of the emissions samples identify compounds observed in all three samples: e-liquid, impinge, and filter pads, and each subset thereof. A limited number of compounds were observed in emissions captured with impingers, but were not observed in emissions captured using filter pads; a larger number of compounds were observed on emissions collected from the filter pads, but not those captured with impingers. It is demonstrated that sampling methods have different sampling efficiencies and some compounds might be missed using only one method. It is recommended to investigate filter pads, impingers, thermal desorption tubes, and solvent extraction resins to establish robust sampling methods for emissions testing of e-cigarette emissions. PMID:29438289
40 CFR 63.4291 - What are my options for meeting the emission limits?
Code of Federal Regulations, 2010 CFR
2010-07-01
... emission capture systems and add-on controls, the organic HAP emission rate for the web coating/printing... demonstrate that all capture systems and control devices for the web coating/printing operation(s) meet the... capture systems and control devices for the web coating/printing operation(s) meet the operating limits...
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.
[Carbon capture and storage (CCS) and its potential role to mitigate carbon emission in China].
Chen, Wen-Ying; Wu, Zong-Xin; Wang, Wei-Zhong
2007-06-01
Carbon capture and storage (CCS) has been widely recognized as one of the options to mitigate carbon emission to eventually stabilize carbon dioxide concentration in the atmosphere. Three parts of CCS, which are carbon capture, transport, and storage are assessed in this paper, covering comparisons of techno-economic parameters for different carbon capture technologies, comparisons of storage mechanism, capacity and cost for various storage formations, and etc. In addition, the role of CCS to mitigate global carbon emission is introduced. Finally, China MARKAL model is updated to include various CCS technologies, especially indirect coal liquefaction and poly-generation technologies with CCS, in order to consider carbon emission reduction as well as energy security issue. The model is used to generate different scenarios to study potential role of CCS to mitigate carbon emissions by 2050 in China. It is concluded that application of CCS can decrease marginal abatement cost and the decrease rate can reach 45% for the emission reduction rate of 50%, and it can lessen the dependence on nuclear power development for stringent carbon constrains. Moreover, coal resources can be cleanly used for longer time with CCS, e.g., for the scenario C70, coal share in the primary energy consumption by 2050 will increase from 10% when without CCS to 30% when with CCS. Therefore, China should pay attention to CCS R&D activities and to developing demonstration projects.
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.
Code of Federal Regulations, 2011 CFR
2011-07-01
... system and add-on control device operating limits during the performance test? 63.4966 Section 63.4966... outlet gas temperature is the maximum operating limit for your condenser. (e) Emission capture system... with Add-on Controls Option § 63.4966 How do I establish the emission capture system and add-on control...
Code of Federal Regulations, 2010 CFR
2010-07-01
... system and add-on control device operating limits during the performance test? 63.4966 Section 63.4966... outlet gas temperature is the maximum operating limit for your condenser. (e) Emission capture system... with Add-on Controls Option § 63.4966 How do I establish the emission capture system and add-on control...
Rao, Anand B; Rubin, Edward S
2002-10-15
Capture and sequestration of CO2 from fossil fuel power plants is gaining widespread interest as a potential method of controlling greenhouse gas emissions. Performance and cost models of an amine (MEA)-based CO2 absorption system for postcombustion flue gas applications have been developed and integrated with an existing power plant modeling framework that includes multipollutant control technologies for other regulated emissions. The integrated model has been applied to study the feasibility and cost of carbon capture and sequestration at both new and existing coal-burning power plants. The cost of carbon avoidance was shown to depend strongly on assumptions about the reference plant design, details of the CO2 capture system design, interactions with other pollution control systems, and method of CO2 storage. The CO2 avoidance cost for retrofit systems was found to be generally higher than for new plants, mainly because of the higher energy penalty resulting from less efficient heat integration as well as site-specific difficulties typically encountered in retrofit applications. For all cases, a small reduction in CO2 capture cost was afforded by the SO2 emission trading credits generated by amine-based capture systems. Efforts are underway to model a broader suite of carbon capture and sequestration technologies for more comprehensive assessments in the context of multipollutant environmental management.
40 CFR 63.4361 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
... from the web coating/printing operation surfaces they are applied to occurs within the capture system... system efficiency? 63.4361 Section 63.4361 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... emission capture system efficiency? You must use the procedures and test methods in this section to...
Bealey, W J; Dore, A J; Dragosits, U; Reis, S; Reay, D S; Sutton, M A
2016-01-01
Trees are very effective at capturing both gaseous and particulate pollutants from the atmosphere. But while studies have often focussed on PM and NOx in the urban environment, little research has been carried out on the tree effect of capturing gaseous emissions of ammonia in the rural landscape. To examine the removal or scavenging of ammonia by trees a long-range atmospheric model (FRAME) was used to compare two strategies that could be used in emission reduction policies anywhere in the world where nitrogen pollution from agriculture is a problem. One strategy was to reduce the emission source strength of livestock management systems by implementing two 'tree-capture' systems scenarios - tree belts downwind of housing and managing livestock under trees. This emission reduction can be described as an 'on-farm' emission reduction policy, as ammonia is 'stopped' from dispersion outside the farm boundaries. The second strategy was to apply an afforestation policy targeting areas of high ammonia emission through two planting scenarios of increasing afforestation by 25% and 50%. Both strategies use trees with the aim of intercepting NH3 emissions to protect semi-natural areas. Scenarios for on-farm emission reductions showed national reductions in nitrogen deposition to semi-natural areas of 0.14% (0.2 kt N-NHx) to 2.2% (3.15 kt N-NHx). Scenarios mitigating emissions from cattle and pig housing gave the highest reductions. The afforestation strategy showed national reductions of 6% (8.4 kt N-NHx) to 11% (15.7 kt N-NHx) for 25% and 50% afforestation scenarios respectively. Increased capture by the planted trees also showed an added benefit of reducing long range effects including a decrease in wet deposition up to 3.7 kt N-NHx (4.6%) and a decrease in export from the UK up to 8.3 kt N-NHx (6.8%). Copyright © 2015 Elsevier Ltd. All rights reserved.
40 CFR 60.265 - Monitoring of operations.
Code of Federal Regulations, 2010 CFR
2010-07-01
... quantity, by weight. (3) Time and duration of each tapping period and the identification of material tapped... only the volumetric flow rate through the capture system for control of emissions from the tapping... performance test. If emissions due to tapping are captured and ducted separately from emissions of the...
Is e+e- pair emission important in the determination of the 3He+4He S factor?
NASA Astrophysics Data System (ADS)
Snover, K. A.; Hurd, A. E.
2003-05-01
We show that the cross section for direct E0 pair emission is related to the cross section for direct E2 photon emission, and is a negligible contribution to the total capture cross section for 3He+4He→7Be. E0 resonance emission, E1 pair emission, and internal conversion are also negligible. Thus there cannot be significant contributions to the 3He+4He→7Be capture cross section at low energies from electromagnetic emission processes other than single photon emission.
NASA Astrophysics Data System (ADS)
Cohen, Stuart M.; Chalmers, Hannah L.; Webber, Michael E.; King, Carey W.
2011-04-01
This work analyses the carbon dioxide (CO2) capture system operation within the Electric Reliability Council of Texas (ERCOT) and Great Britain (GB) electric grids using a previously developed first-order hourly electricity dispatch and pricing model. The grids are compared in their 2006 configuration with the addition of coal-based CO2 capture retrofits and emissions penalties from 0 to 100 US dollars per metric ton of CO2 (USD/tCO2). CO2 capture flexibility is investigated by comparing inflexible CO2 capture systems to flexible ones that can choose between full- and zero-load CO2 capture depending on which operating mode has lower costs or higher profits. Comparing these two grids is interesting because they have similar installed capacity and peak demand, and both are isolated electricity systems with competitive wholesale electricity markets. However, differences in capacity mix, demand patterns, and fuel markets produce diverging behaviours of CO2 capture at coal-fired power plants. Coal-fired facilities are primarily base load in ERCOT for a large range of CO2 prices but are comparably later in the dispatch order in GB and consequently often supply intermediate load. As a result, the ability to capture CO2 is more important for ensuring dispatch of coal-fired facilities in GB than in ERCOT when CO2 prices are high. In GB, higher overall coal prices mean that CO2 prices must be slightly higher than in ERCOT before the emissions savings of CO2 capture offset capture energy costs. However, once CO2 capture is economical, operating CO2 capture on half the coal fleet in each grid achieves greater emissions reductions in GB because the total coal-based capacity is 6 GW greater than in ERCOT. The market characteristics studied suggest greater opportunity for flexible CO2 capture to improve operating profits in ERCOT, but profit improvements can be offset by a flexibility cost penalty.
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.
Monitoring by Control Technique - Capture Systems
Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page is about capture system control techniques used to reduce pollutant emissions.
40 CFR 63.3100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... be in compliance with the operating limits for emission capture systems and add-on control devices...) You must maintain a log detailing the operation and maintenance of the emission capture systems, add... capture system and add-on control device performance tests have been completed, as specified in § 63.3160...
40 CFR 63.3100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... be in compliance with the operating limits for emission capture systems and add-on control devices...) You must maintain a log detailing the operation and maintenance of the emission capture systems, add... capture system and add-on control device performance tests have been completed, as specified in § 63.3160...
40 CFR 63.3100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... be in compliance with the operating limits for emission capture systems and add-on control devices...) You must maintain a log detailing the operation and maintenance of the emission capture systems, add... capture system and add-on control device performance tests have been completed, as specified in § 63.3160...
Code of Federal Regulations, 2014 CFR
2014-07-01
... capture system and add-on control device operating limits during the performance test? 63.4966 Section 63... system and add-on control device operating limits during the performance test? During the performance... outlet gas temperature is the maximum operating limit for your condenser. (e) Emission capture system...
Code of Federal Regulations, 2012 CFR
2012-07-01
... capture system and add-on control device operating limits during the performance test? 63.4966 Section 63... system and add-on control device operating limits during the performance test? During the performance... outlet gas temperature is the maximum operating limit for your condenser. (e) Emission capture system...
Kaewmai, Roihatai; H-Kittikun, Aran; Suksaroj, Chaisri; Musikavong, Charongpun
2013-01-01
Alternative methodologies for the reduction of greenhouse gas (GHG) emissions from crude palm oil (CPO) production by a wet extraction mill in Thailand were developed. The production of 1 t of CPO from mills with biogas capture (four mills) and without biogas capture (two mills) in 2010 produced GHG emissions of 935 kg carbon dioxide equivalent (CO2eq), on average. Wastewater treatment plants with and without biogas capture produced GHG emissions of 64 and 47% of total GHG emission, respectively. The rest of the emissions mostly originated from the acquisition of fresh fruit bunches. The establishment of a biogas recovery system must be the first step in the reduction of GHG emissions. It could reduce GHG emissions by 373 kgCO2eq/t of CPO. The main source of GHG emission of 163 kgCO2eq/t of CPO from the mills with biogas capture was the open pond used for cooling of wastewater before it enters the biogas recovery system. The reduction of GHG emissions could be accomplished by (i) using a wastewater-dispersed unit for cooling, (ii) using a covered pond, (iii) enhancing the performance of the biogas recovery system, and (iv) changing the stabilization pond to an aerated lagoon. By using options i-iv, reductions of GHG emissions of 216, 208, 92.2, and 87.6 kgCO2eq/t of CPO, respectively, can be achieved.
Alternative Fuels Data Center: Maps and Data
emissions comparison of heavy duty vehicles as captured by the Clean Cities Program. Last update February emissions comparison of light duty vehicles as captured by the Clean Cities Program. Last update February
Alternative Fuels Data Center: Maps and Data
gas emissions comparison of heavy duty vehicles as captured by the Clean Cities Program. Last update gas emissions comparison of light duty vehicles as captured by the Clean Cities Program. Last update
Capturing PM2.5 Emissions from 3D Printing via Nanofiber-based Air Filter.
Rao, Chengchen; Gu, Fu; Zhao, Peng; Sharmin, Nusrat; Gu, Haibing; Fu, Jianzhong
2017-09-04
This study investigated the feasibility of using polycaprolactone (PCL) nanofiber-based air filters to capture PM2.5 particles emitted from fused deposition modeling (FDM) 3D printing. Generation and aggregation of emitted particles were investigated under different testing environments. The results show that: (1) the PCL nanofiber membranes are capable of capturing particle emissions from 3D printing, (2) relative humidity plays a signification role in aggregation of the captured particles, (3) generation and aggregation of particles from 3D printing can be divided into four stages: the PM2.5 concentration and particles size increase slowly (first stage), small particles are continuously generated and their concentration increases rapidly (second stage), small particles aggregate into more large particles and the growth of concentration slows down (third stage), the PM2.5 concentration and particle aggregation sizes increase rapidly (fourth stage), and (4) the ultrafine particles denoted as "building unit" act as the fundamentals of the aggregated particles. This work has tremendous implications in providing measures for controlling the particle emissions from 3D printing, which would facilitate the extensive application of 3D printing. In addition, this study provides a potential application scenario for nanofiber-based air filters other than laboratory theoretical investigation.
40 CFR 63.4352 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2010 CFR
2010-07-01
..., shutdown, or malfunction of the emission capture system, add-on control device, or web coating/printing... specified in Table 2 to this subpart, then you must assume that the emission capture system and add-on..., thinning, and cleaning materials applied during a deviation on a controlled web coating/printing operation...
Code of Federal Regulations, 2010 CFR
2010-07-01
... capture system and add-on control device operating limits during the performance test? 63.9324 Section 63... Requirements § 63.9324 How do I establish the emission capture system and add-on control device operating... the operating limits required by § 63.9302 according to this section, unless you have received...
Code of Federal Regulations, 2012 CFR
2012-07-01
... capture system and add-on control device operating limits during the performance test? 63.9324 Section 63... Requirements § 63.9324 How do I establish the emission capture system and add-on control device operating... the operating limits required by § 63.9302 according to this section, unless you have received...
Code of Federal Regulations, 2013 CFR
2013-07-01
... capture system and add-on control device operating limits during the performance test? 63.9324 Section 63... Requirements § 63.9324 How do I establish the emission capture system and add-on control device operating... the operating limits required by § 63.9302 according to this section, unless you have received...
Code of Federal Regulations, 2014 CFR
2014-07-01
... capture system and add-on control device operating limits during the performance test? 63.9324 Section 63... Requirements § 63.9324 How do I establish the emission capture system and add-on control device operating... the operating limits required by § 63.9302 according to this section, unless you have received...
Code of Federal Regulations, 2014 CFR
2014-07-01
... capture system and add-on control device operating limits during the performance test? 63.4567 Section 63... emission capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.4492 according to this section, unless you have received...
Code of Federal Regulations, 2014 CFR
2014-07-01
... capture system and add-on control device operating limits during the performance test? 63.3967 Section 63... establish the emission capture system and add-on control device operating limits during the performance test... must establish the operating limits required by § 63.3892 according to this section, unless you have...
Code of Federal Regulations, 2011 CFR
2011-07-01
... capture system and add-on control device operating limits during the performance test? 63.9324 Section 63... Requirements § 63.9324 How do I establish the emission capture system and add-on control device operating... the operating limits required by § 63.9302 according to this section, unless you have received...
Code of Federal Regulations, 2012 CFR
2012-07-01
... capture system and add-on control device operating limits during the performance test? 63.3967 Section 63... establish the emission capture system and add-on control device operating limits during the performance test... must establish the operating limits required by § 63.3892 according to this section, unless you have...
Code of Federal Regulations, 2012 CFR
2012-07-01
... capture system and add-on control device operating limits during the performance test? 63.4567 Section 63... emission capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.4492 according to this section, unless you have received...
Meteorological air quality forecasting using the WRF-Chem model during the LMOS2017 field campaign
NASA Astrophysics Data System (ADS)
Stanier, C. O.; Abdioskouei, M.; Carmichael, G. R.; Christiansen, M.; Sobhani, N.
2017-12-01
The Lake Michigan Ozone Study (LMOS 2017) occurred during May and June 2017 to address the high ozone episodes in coastal communities surrounding Lake Michigan. Aircraft, ship, mobile lab, and ground-based stations were used in this campaign to build an extensive dataset regarding ozone, its precursors, and particulate matter. The University of Iowa produced high-resolution (4x4 km2 horizontal resolution and 53 vertical levels) forecast products using the WRF-Chem modeling system in support of experimental planning during LMOS 2017. The base forecast system used WRF-Chem 3.6.1 and updated National Emission Inventory (NEI-2011v2). In the updated NEI-2011v2, we reduced the NOx emissions by 28% based on EPA's estimated NOx trends from 2011 to 2017. We ran another daily forecast (perturbed forecast) with 50% reduced NOx emission to capture the sensitivity of ozone to NOx emission and account for the impact of weekend emissions on ozone values. Preliminary in-field evaluation of model performance for clouds, on-shore flows, and surface and aircraft sampled ozone and NOx concentrations found that the model successfully captured much of the observed synoptic variability of onshore flows. The model captured the variability of O3 well, but underpredicted peak ozone during high O3 episodes. In post-campaign WRF-Chem simulations, we investigated the sensitivity of the model to the hydrocarbon emission.
Emerging materials for lowering atmospheric carbon
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
Atmospheric CO2 capture by algae: Negative carbon dioxide emission path.
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.
Code of Federal Regulations, 2013 CFR
2013-07-01
... system and add-on control device operating limits during the performance test? 63.4167 Section 63.4167... Emission Rate with Add-on Controls Option § 63.4167 How do I establish the emission capture system and add-on control device operating limits during the performance test? During the performance test required...
Code of Federal Regulations, 2010 CFR
2010-07-01
... system and add-on control device operating limits during the performance test? 63.3546 Section 63.3546... device or system of multiple capture devices. The average duct static pressure is the maximum operating... Add-on Controls Option § 63.3546 How do I establish the emission capture system and add-on control...
Code of Federal Regulations, 2011 CFR
2011-07-01
... system and add-on control device operating limits during the performance test? 63.3546 Section 63.3546... device or system of multiple capture devices. The average duct static pressure is the maximum operating... Add-on Controls Option § 63.3546 How do I establish the emission capture system and add-on control...
Ağralı, Semra; Üçtuğ, Fehmi Görkem; Türkmen, Burçin Atılgan
2018-06-01
We consider fossil-fired power plants that operate in an environment where a cap and trade system is in operation. These plants need to choose between carbon capture and storage (CCS), carbon capture and utilization (CCU), or carbon trading in order to obey emissions limits enforced by the government. We develop a mixed-integer programming model that decides on the capacities of carbon capture units, if it is optimal to install them, the transportation network that needs to be built for transporting the carbon captured, and the locations of storage sites, if they are decided to be built. Main restrictions on the system are the minimum and maximum capacities of the different parts of the pipeline network, the amount of carbon that can be sold to companies for utilization, and the capacities on the storage sites. Under these restrictions, the model aims to minimize the net present value of the sum of the costs associated with installation and operation of the carbon capture unit and the transportation of carbon, the storage cost in case of CCS, the cost (or revenue) that results from the emissions trading system, and finally the negative revenue of selling the carbon to other entities for utilization. We implement the model on General Algebraic Modeling System (GAMS) by using data associated with two coal-fired power plants located in different regions of Turkey. We choose enhanced oil recovery (EOR) as the process in which carbon would be utilized. The results show that CCU is preferable to CCS as long as there is sufficient demand in the EOR market. The distance between the location of emission and location of utilization/storage, and the capacity limits on the pipes are an important factor in deciding between carbon capture and carbon trading. At carbon prices over $15/ton, carbon capture becomes preferable to carbon trading. These results show that as far as Turkey is concerned, CCU should be prioritized as a means of reducing nation-wide carbon emissions in an environmentally and economically rewarding manner. The model developed in this study is generic, and it can be applied to any industry at any location, as long as the required inputs are available. Copyright © 2018 Elsevier Ltd. All rights reserved.
Can Biochar Covers Reduce Emissions from Manure Lagoons While Capturing Nutrients?
The unique physical and chemical properties of biochars make them promising materials for odor, gas, and nutrient sorption. Floating covers made from organic materials (biocovers) are one option for reducing odor and gas emissions from livestock manure lagoons. This study evaluat...
PROCEDURE FOR ESTIMATING PERMANENT TOTAL ENCLOSURE COSTS
The paper discusses a procedure for estimating permanent total enclosure (PTE) costs. (NOTE: Industries that use add-on control devices must adequately capture emissions before delivering them to the control device. One way to capture emissions is to use PTEs, enclosures that mee...
Gasoline: The Achilles Heel of U.S. Energy Security
2010-03-01
reduce demand for petroleum, improve energy efficiency, and develop feasible alternative energy solutions to include emission capture technologies. The...United States remains the largest consumer of energy products in the world and is the second leading producer of green house gas (GHG) emissions ...energy solutions to include emission capture technologies. The United States remains the largest consumer of energy products in the world and is the
Illinois SB 1987: the Clean Coal Portfolio Standard Law
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
On January 12, 2009, Governor Rod Blagojevich signed SB 1987, the Clean Coal Portfolio Standard Law. The legislation establishes emission standards for new coal-fueled power plants power plants that use coal as their primary feedstock. From 2009-2015, new coal-fueled power plants must capture and store 50 percent of the carbon emissions that the facility would otherwise emit; from 2016-2017, 70 percent must be captured and stored; and after 2017, 90 percent must be captured and stored. SB 1987 also establishes a goal of having 25 percent of electricity used in the state to come from cost-effective coal-fueled power plants thatmore » capture and store carbon emissions by 2025. Illinois is the first state to establish a goal for producing electricity from coal-fueled power plants with carbon capture and storage (CCS). To support the commercial development of CCS technology, the legislation guarantees purchase agreements for the first Illinois coal facility with CCS technology, the Taylorville Energy Center (TEC); Illinois utilities are required to purchase at least 5 percent of their electricity supply from the TEC, provided that customer rates experience only modest increases. The TEC is expected to be completed in 2014 with the ability to capture and store at least 50 percent of its carbon emissions.« less
Francisca, Franco Matías; Montoro, Marcos Alexis; Glatstein, Daniel Alejandro
2017-05-01
Landfill gas (LFG) management is one of the most important tasks for landfill operation and closure because of its impact in potential global warming. The aim of this work is to present a case history evaluating an LFG capture and treatment system for the present landfill facility in Córdoba, Argentina. The results may be relevant for many developing countries around the world where landfill gas is not being properly managed. The LFG generation is evaluated by modeling gas production applying the zero-order model, Landfill Gas Emissions Model (LandGEM; U.S. Environmental Protection Agency [EPA]), Scholl Canyon model, and triangular model. Variability in waste properties, weather, and landfill management conditions are analyzed in order to evaluate the feasibility of implementing different treatment systems. The results show the advantages of capturing and treating LFG in order to reduce the emissions of gases responsible for global warming and to determine the revenue rate needed for the project's financial requirements. This particular project reduces by half the emission of equivalent tons of carbon dioxide (CO 2 ) compared with the situation where there is no gas treatment. In addition, the study highlights the need for a change in the electricity prices if it is to be economically feasible to implement the project in the current Argentinean electrical market. Methane has 21 times more greenhouse gas potential than carbon dioxide. Because of that, it is of great importance to adequately manage biogas emissions from landfills. In addition, it is environmentally convenient to use this product as an alternative energy source, since it prevents methane emissions while preventing fossil fuel consumption, minimizing carbon dioxide emissions. Performed analysis indicated that biogas capturing and energy generation implies 3 times less equivalent carbon dioxide emissions; however, a change in the Argentinean electrical market fees are required to guarantee the financial feasibility of the project.
ANALYSIS OF LEAD IN CANDLE PARTICULATE EMISSIONS BY XRF USING UNIQUANT 4
As part of an extensive program to study the small combustion sources of indoor fine particulate matter (PM), candles with lead-core wicks were burned in a 46-L glass flow- through chamber. The particulate emissions with aerodynamic diameters <10 micrometers (PM10) were captured ...
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.
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.
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.
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
Energy and material balance of CO2 capture from ambient air.
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.
40 CFR 63.11516 - What are my standards and management practices?
Code of Federal Regulations, 2013 CFR
2013-07-01
... capture emissions and vent them to a filtration control device. You must operate the filtration control... requirement by maintaining a record of the manufacturer's specifications for the filtration control devices... to emit MFHAP. (1) You must capture emissions and vent them to a filtration control device. You must...
Life cycle assessment of carbon capture and utilization from ammonia process in Mexico.
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.
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.
Tropospheric Emissions: Monitoring of Pollution (TEMPO) - Status and Potential Science Studies
NASA Astrophysics Data System (ADS)
Chance, Kelly
2016-05-01
TEMPO is the first NASA Earth Venture Instrument, to launch between 2019 and 2021. It measures atmospheric pollution from Mexico City and Cuba to the Canadian oil sands, and from the Atlantic to the Pacific, hourly at high spatial resolution, ~ 10 km2. It measures the key elements of air pollution chemistry. Geostationary (GEO) measurements capture the variability in the diurnal cycle of emissions and chemistry at sub-urban scale to improve emission inventories, monitor population exposure, and enable emission-control strategies. TEMPO measures the UV/visible spectra to retrieve O3, NO2, SO2, H2 CO, C2 H2 O2, H2 O, aerosols, cloud parameters, and UVB radiation. It tracks aerosol loading. It provides near-real-time air quality products. TEMPO is the North American component of the global geostationary constellation for pollution monitoring, with the European Sentinel-4 and the Korean GEMS. TEMPO studies may include: Solar-induced fluorescence from chlorophyll over land and in the ocean to study tropical dynamics, primary productivity, carbon uptake, to detect red tides, and to study phytoplankton; Measurements of stratospheric intrusions that cause air quality exceedances; Measurements at peaks in vehicle travel to capture the variability in emissions from mobile sources; Measurements of thunderstorm activity, including outflow regions to better quantify lightning NOx and O3 production; Cropland measurements follow the temporal evolution of emissions after fertilizer application and from rain-induced emissions from semi-arid soils; Measurements investigate the chemical processing of primary fire emissions and the secondary formation of VOCs and ozone; Measurements examine ocean halogen emissions and their impact on the oxidizing capacity of coastal environments; Spectra of nighttime lights are markers for human activity, energy conservation, and compliance with outdoor lighting standards intended to reduce light pollution.
Hirst, Deborah V.L.; Dunn, Kevin H.; Shulman, Stanley A.; Hammond, Duane R.; Sestito, Nicholas
2015-01-01
Exposures to diacetyl, a primary ingredient of butter flavoring, have been shown to cause respiratory disease among workers who mix flavorings. This study focused on evaluating ventilation controls designed to reduce emissions from the flavor mixing tanks, the major source of diacetyl in the plants. Five exhaust hood configurations were evaluated in the laboratory: standard hinged lid-opened, standard hinged lid-closed, hinged lid-slotted, dome with 38-mm gap, and dome with 114-mm gap. Tracer gas tests were performed to evaluate quantitative capture efficiency for each hood. A perforated copper coil was used to simulate an area source within the 1.2-meter diameter mixing tank. Capture efficiencies were measured at four hood exhaust flow rates (2.83, 5.66, 11.3, and 17.0 cubic meters per minute) and three cross draft velocities (0, 30, and 60 meters per minute). All hoods evaluated performed well with capture efficiencies above 90% for most combinations of exhaust volume and cross drafts. The standard hinged lid was the least expensive to manufacture and had the best average capture efficiency (over 99%) in the closed configuration for all exhaust flow rates and cross drafts. The hinged lid-slotted hood had some of the lowest capture efficiencies at the low exhaust flow rates compared to the other hood designs. The standard hinged lid performed well, even in the open position, and it provided a flexible approach to controlling emissions from mixing tanks. The dome hood gave results comparable to the standard hinged lid but it is more expensive to manufacture. The results of the study indicate that emissions from mixing tanks used in the production of flavorings can be controlled using simple inexpensive exhaust hoods. PMID:24649880
Zhu, Liang; Schade, Gunnar Wolfgang; Nielsen, Claus Jørgen
2013-12-17
We demonstrate the capabilities and properties of using Proton Transfer Reaction time-of-flight mass spectrometry (PTR-ToF-MS) to real-time monitor gaseous emissions from industrial scale amine-based carbon capture processes. The benchmark monoethanolamine (MEA) was used as an example of amines needing to be monitored from carbon capture facilities, and to describe how the measurements may be influenced by potentially interfering species in CO2 absorber stack discharges. On the basis of known or expected emission compositions, we investigated the PTR-ToF-MS MEA response as a function of sample flow humidity, ammonia, and CO2 abundances, and show that all can exhibit interferences, thus making accurate amine measurements difficult. This warrants a proper sample pretreatment, and we show an example using a dilution with bottled zero air of 1:20 to 1:10 to monitor stack gas concentrations at the CO2 Technology Center Mongstad (TCM), Norway. Observed emissions included many expected chemical species, dominantly ammonia and acetaldehyde, but also two new species previously not reported but emitted in significant quantities. With respect to concerns regarding amine emissions, we show that accurate amine quantifications in the presence of water vapor, ammonia, and CO2 become feasible after proper sample dilution, thus making PTR-ToF-MS a viable technique to monitor future carbon capture facility emissions, without conventional laborious sample pretreatment.
40 CFR 63.9322 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
... capture system efficiency? 63.9322 Section 63.9322 Protection of Environment ENVIRONMENTAL PROTECTION... capture system efficiency? You must use the procedures and test methods in this section to determine capture efficiency as part of the performance test required by § 63.9310. (a) Assuming 100 percent capture...
40 CFR 63.9322 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
... capture system efficiency? 63.9322 Section 63.9322 Protection of Environment ENVIRONMENTAL PROTECTION... capture system efficiency? You must use the procedures and test methods in this section to determine capture efficiency as part of the performance test required by § 63.9310. (a) Assuming 100 percent capture...
Radio Frequency Compatibility of an RFID Tag on Glideslope Navigation Receivers
NASA Technical Reports Server (NTRS)
Nguyen, Truong X.; Mielnik, John J.
2008-01-01
A process is demonstrated to show compatibility between a radio frequency identification (RFID) tag and an aircraft glideslope (GS) radio receiver. The particular tag chosen was previously shown to have significant peak spurious emission levels that far exceeded the emission limits in the GS aeronautical band. The spurious emissions are emulated in the study by capturing the RFID fundamental transmission and playing back the signal in the GS band. The signal capturing and playback are achieved with a vector signal generator and a spectrum analyzer that can output the in-phase and quadrature components (IQ). The simulated interference signal is combined with a desired GS signal before being injected into a GS receiver s antenna port for interference threshold determination. Minimum desired propagation loss values to avoid interference are then computed and compared against actual propagation losses for several aircraft.
40 CFR 63.3100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... compliance with the operating limits for emission capture systems and add-on control devices required by § 63... maintain a log detailing the operation and maintenance of the emission capture systems, add-on control... add-on control device performance tests have been completed, as specified in § 63.3160. (f) If your...
40 CFR 63.3100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... compliance with the operating limits for emission capture systems and add-on control devices required by § 63... maintain a log detailing the operation and maintenance of the emission capture systems, add-on control... add-on control device performance tests have been completed, as specified in § 63.3160. (f) If your...
40 CFR 63.4491 - What are my options for meeting the emission limits?
Code of Federal Regulations, 2010 CFR
2010-07-01
... CATEGORIES National Emission Standards for Hazardous Air Pollutants for Surface Coating of Plastic Parts and... reductions achieved by emission capture systems and add-on controls, the organic HAP emission rate for the...
Developing particle emission inventories using remote sensing (PEIRS).
Tang, Chia-Hsi; Coull, Brent A; Schwartz, Joel; Lyapustin, Alexei I; Di, Qian; Koutrakis, Petros
2017-01-01
Information regarding the magnitude and distribution of PM 2.5 emissions is crucial in establishing effective PM regulations and assessing the associated risk to human health and the ecosystem. At present, emission data is obtained from measured or estimated emission factors of various source types. Collecting such information for every known source is costly and time-consuming. For this reason, emission inventories are reported periodically and unknown or smaller sources are often omitted or aggregated at large spatial scale. To address these limitations, we have developed and evaluated a novel method that uses remote sensing data to construct spatially resolved emission inventories for PM 2.5 . This approach enables us to account for all sources within a fixed area, which renders source classification unnecessary. We applied this method to predict emissions in the northeastern United States during the period 2002-2013 using high-resolution 1 km × 1 km aerosol optical depth (AOD). Emission estimates moderately agreed with the EPA National Emission Inventory (R 2 = 0.66-0.71, CV = 17.7-20%). Predicted emissions are found to correlate with land use parameters, suggesting that our method can capture emissions from land-use-related sources. In addition, we distinguished small-scale intra-urban variation in emissions reflecting distribution of metropolitan sources. In essence, this study demonstrates the great potential of remote sensing data to predict particle source emissions cost-effectively. We present a novel method, particle emission inventories using remote sensing (PEIRS), using remote sensing data to construct spatially resolved PM 2.5 emission inventories. Both primary emissions and secondary formations are captured and predicted at a high spatial resolution of 1 km × 1 km. Using PEIRS, large and comprehensive data sets can be generated cost-effectively and can inform development of air quality regulations.
Gunter, Stacey A; Bradford, James A; Moffet, Corey A
2017-01-01
Methane (CH) and carbon dioxide (CO) represent 11 and 81%, respectively, of all anthropogenic greenhouse gas emissions. Agricultural CH emissions account for approximately 43% of all anthropogenic CH emissions. Most agricultural CH emissions are attributed to enteric fermentation within ruminant livestock; hence, the heightened interest in quantifying and mitigating this source. The automated, open-circuit gas quantification system (GQS; GreenFeed, C-Lock, Inc., Rapid City, SD) evaluated here can be placed in a pasture with grazing cattle and can measure their CH and CO emissions with spot sampling. However, improper management of the GQS can have an erroneous effect on emission estimates. One factor affecting the quality of emission estimates is the airflow rates through the GQS to ensure a complete capture of the breath cloud emitted by the animal. It is hypothesized that at lower airflow rates this cloud will be incompletely captured. To evaluate the effect of airflow rate through the GQS on emission estimates, a data set was evaluated with 758 CO and CH emission estimates with a range in airflows of 10.7 to 36.6 L/s. When airflow through the GQS was between 26.0 and 36.6 L/s, CO and CH emission estimates were not affected ( = 0.14 and 0.05, respectively). When airflow rates were less than 26.0 L/s, CO and CH emission estimates were lower and decreased as airflow rate decreased ( < 0.0001). We hypothesize that when airflow through the GQS decreases below 26 L/s, breath capture was incomplete and CO and CH emissions are underestimated. Maintaining mass airflow through a GQS at rates greater than 26 L/s is important for producing high quality CO and CH emission estimates.
Radio Frequency Compatibility of an RFID Tag on Glideslope Navigation Receivers
NASA Technical Reports Server (NTRS)
Nguyen, Truong X.; Mielnik, John J.
2008-01-01
A process is demonstrated to show compatibility between a radio frequency identification (RFID) tag and an aircraft glideslope (GS) radio r eceiver. The particular tag chosen was previously shown to have significant spurious emission levels that exceeded the emission limit in th e GS aeronautical band. The spurious emissions are emulated in the study by capturing the RFID fundamental transmission and playing back th e signal in the GS band. The signal capturing and playback are achiev ed with a vector signal generator and a spectrum analyzer that can output the in-phase and quadrature components (IQ). The simulated interf erence signal is combined with a GS signal before being injected into a GS receiver#s antenna port for interference threshold determination . Minimum desired propagation loss values to avoid interference are then computed and compared against actual propagation losses for severa l aircraft.
40 CFR 63.4900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... the provisions in § 63.6(e)(1)(i). (c) If your affected source uses an emission capture system and add... address the startup, shutdown, and corrective actions in the event of a malfunction of the emission capture system or the add-on control device. The SSMP must also address any coating operation equipment...
40 CFR 63.4900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... the provisions in § 63.6(e)(1)(i). (c) If your affected source uses an emission capture system and add... address the startup, shutdown, and corrective actions in the event of a malfunction of the emission capture system or the add-on control device. The SSMP must also address any coating operation equipment...
40 CFR 63.4165 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2014 CFR
2014-07-01
... of appendix M to 40 CFR part 51 to determine the mass fraction of TVH liquid input from each coating... materials used in the coating operation during the capture efficiency test run, kg. TVHi = mass fraction of... compares the mass of liquid TVH in materials used in the coating operation, to the mass of TVH emissions...
40 CFR 63.4165 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2012 CFR
2012-07-01
... of appendix M to 40 CFR part 51 to determine the mass fraction of TVH liquid input from each coating... materials used in the coating operation during the capture efficiency test run, kg. TVHi = mass fraction of... compares the mass of liquid TVH in materials used in the coating operation, to the mass of TVH emissions...
40 CFR 63.3965 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
... Method 204A or 204F of appendix M to 40 CFR part 51 to determine the mass fraction of TVH liquid input... temporary total enclosure or building enclosure. The liquid-to-uncaptured-gas protocol compares the mass of liquid TVH in materials used in the coating operation to the mass of TVH emissions not captured by the...
Code of Federal Regulations, 2010 CFR
2010-07-01
... system and add-on control device operating limits during the performance test? 63.3556 Section 63.3556... of key parameters of the valve operating system (e.g., solenoid valve operation, air pressure.../outlet Concentration Option § 63.3556 How do I establish the emission capture system and add-on control...
Code of Federal Regulations, 2013 CFR
2013-07-01
... system and add-on control device operating limits during the performance test? 63.3967 Section 63.3967... emission capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.3892 according to this section, unless you have received...
Code of Federal Regulations, 2011 CFR
2011-07-01
... system and add-on control device operating limits during the performance test? 63.3556 Section 63.3556... of key parameters of the valve operating system (e.g., solenoid valve operation, air pressure.../outlet Concentration Option § 63.3556 How do I establish the emission capture system and add-on control...
Code of Federal Regulations, 2013 CFR
2013-07-01
... system and add-on control device operating limits during the performance test? 63.3556 Section 63.3556... of key parameters of the valve operating system (e.g., solenoid valve operation, air pressure... Control Efficiency/outlet Concentration Option § 63.3556 How do I establish the emission capture system...
Talati, Shuchi; Zhai, Haibo; Morgan, M Granger
2016-12-06
Using data on the coal-fired electric generating units (EGUs) in Texas we assess the economic feasibility of retrofitting existing units with carbon capture and sequestration (CCS) in order to comply with the Clean Power Plan's rate-based emission standards under an emission trading scheme. CCS with 90% capture is shown to be more economically attractive for a range of existing units than purchasing emission rate credits (ERCs) from a trading market at an average credit price above $28 per MWh under the final state standard and $35 per MWh under the final national standard. The breakeven ERC trading prices would decrease significantly if the captured CO 2 were sold for use in enhanced oil recovery, making CCS retrofits viable at lower trading prices. The combination of ERC trading and CO 2 use can greatly reinforce economic incentives and market demands for CCS and hence accelerate large-scale deployment, even under scenarios with high retrofit costs. Comparing the levelized costs of electricity generation between CCS retrofits and new renewable plants under the ERC trading scheme, retrofitting coal-fired EGUs with CCS may be significantly cheaper than new solar plants under some market conditions.
Feasibility study of algae-based Carbon Dioxide capture ...
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
Sathre, Roger; Masanet, Eric
2012-09-04
To understand the long-term energy and climate implications of different implementation strategies for carbon capture and storage (CCS) in the US coal-fired electricity fleet, we integrate three analytical elements: scenario projection of energy supply systems, temporally explicit life cycle modeling, and time-dependent calculation of radiative forcing. Assuming continued large-scale use of coal for electricity generation, we find that aggressive implementation of CCS could reduce cumulative greenhouse gas emissions (CO(2), CH(4), and N(2)O) from the US coal-fired power fleet through 2100 by 37-58%. Cumulative radiative forcing through 2100 would be reduced by only 24-46%, due to the front-loaded time profile of the emissions and the long atmospheric residence time of CO(2). The efficiency of energy conversion and carbon capture technologies strongly affects the amount of primary energy used but has little effect on greenhouse gas emissions or radiative forcing. Delaying implementation of CCS deployment significantly increases long-term radiative forcing. This study highlights the time-dynamic nature of potential climate benefits and energy costs of different CCS deployment pathways and identifies opportunities and constraints of successful CCS implementation.
Economic and environmental benefits of landfill gas utilisation in Oman.
Abushammala, Mohammed Fm; Qazi, Wajeeha A; Azam, Mohammed-Hasham; Mehmood, Umais A; Al-Mufragi, Ghithaa A; Alrawahi, Noor-Alhuda
2016-08-01
Municipal solid waste disposed in landfill sites decomposes under anaerobic conditions and produces so-called landfill-gas, which contains 30%-40% of carbon dioxide (CO2) and 50%-60% of methane (CH4). Methane has the potential of causing global warming 25 times more than CO2 Therefore, migration of landfill-gas from landfills to the surrounding environment can potentially affect human life and environment. Thus, this research aims to determine municipal solid waste generation in Oman over the years 1971-2030, to quantify annual CH4 emissions inventory that resulted from this waste over the same period of time, and to determine the economic and environmental benefits of capturing the CH4 gas for energy production. It is found that cumulative municipal solid waste landfilled in Oman reaches 3089 Giga gram (Gg) in the year 2030, of which approximately 85 Gg of CH4 emissions are produced in the year 2030. The study also found that capturing CH4 emissions between the years 2016 and 2030 could attract revenues of up to US$333 million and US$291 million from the carbon reduction and electricity generation, simultaneously. It is concluded that CH4 emissions from solid waste in Oman increases enormously with time, and capture of this gas for energy production could provide a sustainable waste management solution in Oman. © The Author(s) 2016.
Ge, Jianping; Lei, Yalin; Xu, Qun; Wang, Xibo
2016-01-01
In this study, a decomposition and emissions matrix is developed to identify the roles (giver or taker) played by the sectors in the greenhouse gas emissions for the economy of Beijing in China. Our results indicate that services were the most important emitter if we consider the total (direct and indirect) emissions. In addition to Construction, Scientific studies and technical services and Finance sectors of services were the largest takers. They have a large role in boosting greenhouse gas emissions throughout the economy of Beijing. As the basis and supporter of production activities, the electricity production and the transportation sectors were the greatest givers. More emphasis should be placed on using clean energy and carbon capture and storage technologies to reduce emissions within these sectors. Based on the roles played by these sectors in greenhouse gas emissions, some policy implications were proposed for energy utilization and carbon emissions trading.
40 CFR 63.3965 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
...; coating solvent flash-off, curing, and drying occurs within the capture system; and the removal or... spray booth and a curing oven. (b) Measuring capture efficiency. If the capture system does not meet... surface preparation activities and drying and curing time. (c) Liquid-to-uncaptured-gas protocol using a...
NASA Astrophysics Data System (ADS)
Elkafrawy, Tamer Mohammad Samy
Radiative double electron capture (RDEC) is a one-step process in ion-atom collisions occurring when two target electrons are captured to a bound state of the projectile simultaneously with the emission of a single photon. The emitted photon has approximately double the energy of the photon emitted due to radiative electron capture (REC), which occurs when a target electron is captured to a projectile bound state with simultaneous emission of a photon. REC and RDEC can be treated as time-reversed photoionization (PI) and double photoionization (DPI), respectively, if loosely-bound target electrons are captured. This concept can be formulated with the principle of detailed balance, in which the processes of our interest can be described in terms of their time-reversed ones. Fully-stripped ions were used as projectiles in the performed RDEC experiments, providing a recipient system free of electron-related Coulomb fields. This allows the target electrons to be transferred without interaction with any of the projectile electrons, enabling accurate investigation of the electron-electron interaction in the vicinity of electromagnetic field. In this dissertation, RDEC was investigated during the collision of fully-stripped fluorine ions with a thin carbon foil and the results are compared with the recent experimental and theoretical studies. In the current work, x rays associated with projectile charge-changing by single and double electron capture and no charge change by F9+ ions were observed and compared with recent work for O8+ ions and with theory. Both the F 9+ and O8+ ions had energies in the ˜MeV/u range. REC, in turn, was investigated as a means to compare with the theoretical predictions of the RDEC/REC cross section ratio. The most significant background processes including various mechanisms of x-ray emission that may interfere with the energy region of interest are addressed in detail. This enables isolation of the contributions of REC and RDEC from the entire continuous spectrum of x-ray emission or at least ensures that the background processes have negligible contribution to the energy range of interest. Special emphasis is given to showing how the data analysis was carried out by the subtraction of the x rays due to contamination lines.
40 CFR 63.3544 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
... the coating operation during the capture efficiency test run, kg. TVHi = Mass fraction of TVH in... the mass of liquid TVH in materials used in the coating operation to the mass of TVH emissions not... 40 CFR part 51. (2) Use Method 204A or 204F of appendix M to 40 CFR part 51 to determine the mass...
Code of Federal Regulations, 2011 CFR
2011-07-01
... system and add-on control device operating limits during the performance test? 63.4767 Section 63.4767... Rate with Add-on Controls Option § 63.4767 How do I establish the emission capture system and add-on control device operating limits during the performance test? During the performance test required by § 63...
Code of Federal Regulations, 2010 CFR
2010-07-01
... system and add-on control device operating limits during the performance test? 63.4767 Section 63.4767... Rate with Add-on Controls Option § 63.4767 How do I establish the emission capture system and add-on control device operating limits during the performance test? During the performance test required by § 63...
Code of Federal Regulations, 2010 CFR
2010-07-01
... system and add-on control device operating limits during the performance test? 63.4167 Section 63.4167... with Add-on Controls Option § 63.4167 How do I establish the emission capture system and add-on control device operating limits during the performance test? During the performance test required by § 63.4160...
Code of Federal Regulations, 2011 CFR
2011-07-01
... system and add-on control device operating limits during the performance test? 63.4167 Section 63.4167... with Add-on Controls Option § 63.4167 How do I establish the emission capture system and add-on control device operating limits during the performance test? During the performance test required by § 63.4160...
Variable pressure ionization detector for gas chromatography
Buchanan, Michelle V.; Wise, Marcus B.
1988-01-01
Method and apparatus for differentiating organic compounds based on their electron affinity. An electron capture detector cell (ECD) is operated at pressures ranging from atmospheric to less than 1 torr. Through variation of the pressure within the ECD cell, the organic compounds are induced to either capture or emit electrons. Differentiation of isomeric compounds can be obtianed when, at a given pressure, one isomer is in the emission mode and the other is in the capture mode. Output of the ECD is recorded by chromatogram. The invention also includes a method for obtaining the zero-crossing pressure of a compound, defined as the pressure at which the competing emission and capture reactions are balanced and which may be correlated to the electron affinity of a compound.
Code of Federal Regulations, 2014 CFR
2014-07-01
... capture system and add-on control device operating limits during the performance test? 63.3546 Section 63... of key parameters of the valve operating system (e.g., solenoid valve operation, air pressure... minimum operating limit for that specific capture device or system of multiple capture devices. The...
Code of Federal Regulations, 2012 CFR
2012-07-01
... capture system and add-on control device operating limits during the performance test? 63.3546 Section 63... of key parameters of the valve operating system (e.g., solenoid valve operation, air pressure... minimum operating limit for that specific capture device or system of multiple capture devices. The...
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
Thiyagarajan, S; Geo, V Edwin; Martin, Leenus Jesu; Nagalingam, B
2018-03-22
This experimental study aims to mitigate harmful emissions from a CI engine using bio-energy with carbon capture and storage (BECCS) approach. The engine used for this experimental work is a single cylinder CI engine with a rated power of 5.2 kW at a constant speed of 1500 rpm. The BECCS approach is a combination of plant-based biofuels and carbon capture and storage (CCS) system. The whole investigation was done in four phases: (1) Substituting diesel with Karanja oil methyl ester (KOME) (2) Equal volume blending of Orange oil (ORG) with KOME (3) 20% blending of n-butanol (B) with KOME-ORG blend (4) CCS system with zeolite based non-selective catalytic reduction (NSCR) and mono ethanolamine (MEA) based selective non-catalytic reduction (SNCR) system with KOME-ORG + B20 blend. The experimental results show that substitution of diesel with KOME reduces smoke emission, but increases NO and CO 2 emission. KOME-ORG blend reduces CO 2 and smoke emissions with high NO emission due to combustion improvement. In comparison with the sole combustion of KOME at full load condition, the combination of KOME-ORG + B20 as bio-fuel with zeolite based post-combustion treatment system resulted in a maximum reduction of NO, smoke and CO 2 emission by 41%, 19% and 15% respectively.
Lando, Asiyanthi Tabran; Nakayama, Hirofumi; Shimaoka, Takayuki
2017-01-01
Methane from landfills contributes to global warming and can pose an explosion hazard. To minimize these effects emissions must be monitored. This study proposed application of portable gas detector (PGD) in point and scanning measurements to estimate spatial distribution of methane emissions in landfills. The aims of this study were to discover the advantages and disadvantages of point and scanning methods in measuring methane concentrations, discover spatial distribution of methane emissions, cognize the correlation between ambient methane concentration and methane flux, and estimate methane flux and emissions in landfills. This study was carried out in Tamangapa landfill, Makassar city-Indonesia. Measurement areas were divided into basic and expanded area. In the point method, PGD was held one meter above the landfill surface, whereas scanning method used a PGD with a data logger mounted on a wire drawn between two poles. Point method was efficient in time, only needed one person and eight minutes in measuring 400m 2 areas, whereas scanning method could capture a lot of hot spots location and needed 20min. The results from basic area showed that ambient methane concentration and flux had a significant (p<0.01) positive correlation with R 2 =0.7109 and y=0.1544 x. This correlation equation was used to describe spatial distribution of methane emissions in the expanded area by using Kriging method. The average of estimated flux from scanning method was 71.2gm -2 d -1 higher than 38.3gm -2 d -1 from point method. Further, scanning method could capture the lower and higher value, which could be useful to evaluate and estimate the possible effects of the uncontrolled emissions in landfill. Copyright © 2016 Elsevier Ltd. All rights reserved.
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
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.
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.
40 CFR 63.4120 - What reports must I submit?
Code of Federal Regulations, 2010 CFR
2010-07-01
... emission limitation (including any periods when emissions bypassed the add-on control device and were... emission reduction during the compliance period by emission capture systems and add-on control devices... of the CPMS. (5) The date of the latest CPMS certification or audit. (6) The date and time that each...
40 CFR 63.4765 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
..., substitute TVH for each occurrence of the term volatile organic compounds (VOC) in the methods. (3) Use... building enclosure. During the capture efficiency measurement, all organic compound emitting operations... enclosure is a building enclosure. During the capture efficiency measurement, all organic compound emitting...
40 CFR 63.4765 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2013 CFR
2013-07-01
..., substitute TVH for each occurrence of the term volatile organic compounds (VOC) in the methods. (3) Use... building enclosure. During the capture efficiency measurement, all organic compound emitting operations... enclosure is a building enclosure. During the capture efficiency measurement, all organic compound emitting...
Kadhane, U; Misra, D; Singh, Y P; Tribedi, Lokesh C
2003-03-07
Projectile deexcitation Lyman x-ray emission following electron capture and K excitation has been studied in collisions of bare and Li-like sulphur ions (of energy 110 MeV) with fullerenes (C(60)/C(70)) and different gaseous targets. The intensity ratios of different Lyman x-ray lines in collisions with fullerenes are found to be substantially lower than those for the gas targets, both for capture and excitation. This has been explained in terms of a model based on "solidlike" effect, namely, wakefield induced stark mixing of the excited states populated via electron capture or K excitation: a collective phenomenon of plasmon excitation in the fullerenes under the influence of heavy, highly charged ions.
Peng, Tzu-Huan; Lin, Chiou-Liang
2014-12-15
In this study, a pilot-scale low-temperature two-stage fluidized bed incinerator was evaluated for the control of heavy metal emissions using various chlorine (Cl) additives. Artificial waste containing heavy metals was selected to simulate municipal solid waste (MSW). Operating parameters considered included the first-stage combustion temperature, gas velocity, and different kinds of Cl additives. Results showed that the low-temperature two-stage fluidized bed reactor can be an effective system for the treatment of MSW because of its low NO(x), CO, HCl, and heavy metal emissions. The NO(x) and HCl emissions could be decreased by 42% and 70%, respectively. Further, the results showed that heavy metal emissions were reduced by bed material adsorption and filtration in the second stage. Regarding the Cl addition, although the Cl addition would reduce the metal capture in the first-stage sand bed, but those emitted metals could be effectively captured by the filtration of second stage. No matter choose what kind of additive, metal emissions in the low-temperature two-stage system are still lower than in a traditional high-temperature one-stage system. The results also showed that metal emissions depend not only on the combustion temperature but also on the physicochemical properties of the different metal species. Copyright © 2014 Elsevier Ltd. All rights reserved.
Multi-Wavelength Views of Protostars in IC 1396
2003-12-18
This archival image from 2003 captured by NASA Spitzer Space Telescope captured the Elephant Trunk Nebula, an elongated dark globule within the emission nebula IC 1396 in the constellation of Cepheus.
Greenhouse gas emissions in an agroforestry system in the southeastern USA
USDA-ARS?s Scientific Manuscript database
Agroforestry systems may provide diverse ecosystem services and economic benefits that conventional agriculture cannot, e.g. potentially mitigating greenhouse gas emissions by enhancing nutrient cycling, since tree roots can capture nutrients not taken up by crops. However, greenhouse gas emission ...
40 CFR 63.1459 - What definitions apply to this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... device that collects particulate matter by filtering the gas stream through bags. A baghouse is also... converter bath. Capture system means the collection of components used to capture gases and fumes released from one or more emission points, and to convey the captured gases and fumes to a control device. A...
40 CFR 63.4181 - What definitions apply to this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... commercial or industrial HVAC systems. Manufacturer's formulation data means data on a material (such as a... capture system efficiency means the portion (expressed as a percentage) of the pollutants from an emission source that is delivered to an add-on control device. Capture system means one or more capture devices...
40 CFR 63.4181 - What definitions apply to this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... commercial or industrial HVAC systems. Manufacturer's formulation data means data on a material (such as a.... Capture efficiency or capture system efficiency means the portion (expressed as a percentage) of the pollutants from an emission source that is delivered to an add-on control device. Capture system means one or...
40 CFR 63.4181 - What definitions apply to this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... commercial or industrial HVAC systems. Manufacturer's formulation data means data on a material (such as a.... Capture efficiency or capture system efficiency means the portion (expressed as a percentage) of the pollutants from an emission source that is delivered to an add-on control device. Capture system means one or...
40 CFR 63.4181 - What definitions apply to this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... commercial or industrial HVAC systems. Manufacturer's formulation data means data on a material (such as a... capture system efficiency means the portion (expressed as a percentage) of the pollutants from an emission source that is delivered to an add-on control device. Capture system means one or more capture devices...
40 CFR 63.4181 - What definitions apply to this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... commercial or industrial HVAC systems. Manufacturer's formulation data means data on a material (such as a.... Capture efficiency or capture system efficiency means the portion (expressed as a percentage) of the pollutants from an emission source that is delivered to an add-on control device. Capture system means one or...
Enhancing the detector for advanced neutron capture experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Couture, A.; Mosby, S.; Baramsai, B.
2015-05-28
The Detector for Advanced Neutron Capture Experiments (DANCE) has been used for extensive studies of neutron capture, gamma decay, photon strength functions, and prompt and delayed fission-gamma emission. Despite these successes, the potential measurements have been limited by the data acquisition hardware. We, thus, report on a major upgrade of the DANCE data acquisition that simultaneously enables strait-forward coupling to auxiliary detectors, including high-resolution high-purity germanium detectors and neutron tagging array. Furthermore, the upgrade will enhance the time domain accessible for time-of-flight neutron measurements as well as improve the resolution in the DANCE barium fluoride crystals for photons.
An, Jing; Li, Yingnan; Middleton, Richard S.
2018-02-20
China is the largest producer of magnesia refractory materials and products in the world, resulting in significant energy consumption and carbon emissions. This paper analyzes measures to reduce both the energy consumption and carbon emissions in the production phase and use phase, providing a theoretical basis for a sustainable magnesia refractory industry. Results show that the total carbon emissions of carbon-containing magnesia bricks produced with fused magnesia are much higher than those of other products, and the total carbon emissions of both general magnesia brick and magnesia-carbon spray are lower than those of other products. Carbon emissions of magnesia productsmore » are mainly concentrated in the production process of magnesia. Manufacturers should select materials with lower environmental impacts and emphasize saving energy and reducing carbon emissions in the magnesia production process. Through scenario analysis we found that CO 2 capture is an effective measure to reduce carbon emissions compared with just improving energy consumption. However, a robust CO 2 market does not currently exist. Policy makers should plan on integrating CO 2 capture in the magnesia industry into a regional CO 2 capture and storage development planning in the long term. In particular, magnesia production is concentrated in a single geographical area which would and thus could take advantage of significant scale effects. Finally, in the use phase, extending the service lifetime reduces carbon emissions over the product lifetime, thus users should attempt to extend the service lifetime of a furnace as a whole. However, results show that it is not advisable to add a large number of repair refractories to extend the lifetime of existing furnaces.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
An, Jing; Li, Yingnan; Middleton, Richard S.
China is the largest producer of magnesia refractory materials and products in the world, resulting in significant energy consumption and carbon emissions. This paper analyzes measures to reduce both the energy consumption and carbon emissions in the production phase and use phase, providing a theoretical basis for a sustainable magnesia refractory industry. Results show that the total carbon emissions of carbon-containing magnesia bricks produced with fused magnesia are much higher than those of other products, and the total carbon emissions of both general magnesia brick and magnesia-carbon spray are lower than those of other products. Carbon emissions of magnesia productsmore » are mainly concentrated in the production process of magnesia. Manufacturers should select materials with lower environmental impacts and emphasize saving energy and reducing carbon emissions in the magnesia production process. Through scenario analysis we found that CO 2 capture is an effective measure to reduce carbon emissions compared with just improving energy consumption. However, a robust CO 2 market does not currently exist. Policy makers should plan on integrating CO 2 capture in the magnesia industry into a regional CO 2 capture and storage development planning in the long term. In particular, magnesia production is concentrated in a single geographical area which would and thus could take advantage of significant scale effects. Finally, in the use phase, extending the service lifetime reduces carbon emissions over the product lifetime, thus users should attempt to extend the service lifetime of a furnace as a whole. However, results show that it is not advisable to add a large number of repair refractories to extend the lifetime of existing furnaces.« less
On-road emissions of light-duty vehicles in europe.
Weiss, Martin; Bonnel, Pierre; Hummel, Rudolf; Provenza, Alessio; Manfredi, Urbano
2011-10-01
For obtaining type approval in the European Union, light-duty vehicles have to comply with emission limits during standardized laboratory emissions testing. Although emission limits have become more stringent in past decades, light-duty vehicles remain an important source of nitrogen oxides and carbon monoxide emissions in Europe. Furthermore, persisting air quality problems in many urban areas suggest that laboratory emissions testing may not accurately capture the on-road emissions of light-duty vehicles. To address this issue, we conduct the first comprehensive on-road emissions test of light-duty vehicles with state-of-the-art Portable Emission Measurement Systems. We find that nitrogen oxides emissions of gasoline vehicles as well as carbon monoxide and total hydrocarbon emissions of both diesel and gasoline vehicles generally remain below the respective emission limits. By contrast, nitrogen oxides emissions of diesel vehicles (0.93 ± 0.39 grams per kilometer [g/km]), including modern Euro 5 diesel vehicles (0.62 ± 0.19 g/km), exceed emission limits by 320 ± 90%. On-road carbon dioxide emissions surpass laboratory emission levels by 21 ± 9%, suggesting that the current laboratory emissions testing fails to accurately capture the on-road emissions of light-duty vehicles. Our findings provide the empirical foundation for the European Commission to establish a complementary emissions test procedure for light-duty vehicles. This procedure could be implemented together with more stringent Euro 6 emission limits in 2014. The envisaged measures should improve urban air quality and provide incentive for innovation in the automotive industry.
Adsorbents for capturing mercury in coal-fired boiler flue gas.
Yang, Hongqun; Xu, Zhenghe; Fan, Maohong; Bland, Alan E; Judkins, Roddie R
2007-07-19
This paper reviews recent advances in the research and development of sorbents used to capture mercury from coal-fired utility boiler flue gas. Mercury emissions are the source of serious health concerns. Worldwide mercury emissions from human activities are estimated to be 1000 to 6000 t/annum. Mercury emissions from coal-fired power plants are believed to be the largest source of anthropogenic mercury emissions. Mercury emissions from coal-fired utility boilers vary in total amount and speciation, depending on coal types, boiler operating conditions, and configurations of air pollution control devices (APCDs). The APCDs, such as fabric filter (FF) bag house, electrostatic precipitator (ESP), and wet flue gas desulfurization (FGD), can remove some particulate-bound and oxidized forms of mercury. Elemental mercury often escapes from these devices. Activated carbon injection upstream of a particulate control device has been shown to have the best potential to remove both elemental and oxidized mercury from the flue gas. For this paper, NORIT FGD activated carbon was extensively studied for its mercury adsorption behavior. Results from bench-, pilot- and field-scale studies, mercury adsorption by coal chars, and a case of lignite-burned mercury control were reviewed. Studies of brominated carbon, sulfur-impregnated carbon and chloride-impregnated carbon were also reviewed. Carbon substitutes, such as calcium sorbents, petroleum coke, zeolites and fly ash were analyzed for their mercury-adsorption performance. At this time, brominated activated carbon appears to be the best-performing mercury sorbent. A non-injection regenerable sorbent technology is briefly introduced herein, and the issue of mercury leachability is briefly covered. Future research directions are suggested.
Room-temperature ionic liquids and composite materials: platform technologies for CO(2) capture.
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.
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2014 CFR
2014-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2012 CFR
2012-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2013 CFR
2013-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2010 CFR
2010-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2011 CFR
2011-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
NASA Astrophysics Data System (ADS)
Rieger, G.; Pinnington, E. H.; Ciubotariu, C.
2000-12-01
Absolute photon emission cross sections following electron capture reactions have been measured for C2+, N3+, N4+ and O3+ ions colliding with Li(2s) atoms at keV energies. The results are compared with calculations using the extended classical over-the-barrier model by Niehaus. We explore the limits of our experimental method and present a detailed discussion of experimental errors.
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.
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
40 CFR 63.4165 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
... system; coating solvent flash-off and coating, curing, and drying occurs within the capture system and... when being moved between a spray booth and a curing oven. (b) If the capture system does not meet both... surface preparation activities and drying or curing time. (c) Liquid-to-uncaptured-gas protocol using a...
Code of Federal Regulations, 2013 CFR
2013-07-01
... system and add-on control device operating limits during the performance test? 63.3546 Section 63.3546... of key parameters of the valve operating system (e.g., solenoid valve operation, air pressure... minimum operating limit for that specific capture device or system of multiple capture devices. The...
Natural gas combined-cycle (NGCC) turbines with carbon capture and storage (CCS) can be a promising technology to reduce CO2 emissions in the electric sector. However, the high cost and energy penalties of current carbon capture devices, as well as methane leakage from natural ga...
Photon emission from quark-gluon plasma out of equilibrium
NASA Astrophysics Data System (ADS)
Hauksson, Sigtryggur; Jeon, Sangyong; Gale, Charles
2018-01-01
The photon emission from a nonequilibrium quark-gluon plasma is analyzed. We derive an integral equation that describes photon production through quark-antiquark annihilation and quark bremsstrahlung. It includes coherence between different scattering sites, also known as the Landau-Pomeranchuk-Migdal effect. These leading-order processes are studied for the first time together in an out-of-equilibrium field theoretical treatment that enables the inclusion of viscous corrections to the calculation of electromagnetic emission rates. In the special case of an isotropic, viscous, plasma the integral equation only depends on three constants, which capture the nonequilibrium nature of the medium.
Saini, R; Khanna, R; Dutta, R K; Cayumil, R; Ikram-Ul-Haq, M; Agarwala, V; Ellamparuthy, G; Jayasankar, K; Mukherjee, P S; Sahajwalla, V
2017-06-01
A novel approach is presented to capture some of the potentially toxic elements (PTEs), other particulates and emissions during the heat treatment of e-waste using alumina adsorbents. Waste PCBs from mobile phones were mechanically crushed to sizes less than 1mm; their thermal degradation was investigated using thermo-gravimetric analysis. Observed weight loss was attributed to the degradation of polymers and the vaporization of organic constituents and volatile metals. The sample assembly containing PCB powder and adsorbent was heat treated at 600°C for times ranging between 10 and 30min with air, nitrogen and argon as carrier gases. Weight gains up to ∼17% were recorded in the adsorbent thereby indicating the capture of significant amounts of particulates. The highest level of adsorption was observed in N 2 atmosphere for small particle sizes of alumina. SEM/EDS results on the adsorbent indicated the presence of Cu, Pb, Si, Mg and C. These studies were supplemented with ICP-OES analysis to determine the extent of various species captured as a function of operating parameters. This innovative, low-cost approach has the potential for utilization in the informal sector and/or developing countries, and could play a significant role in reducing toxic emissions from e-waste processing towards environmentally safe limits. Copyright © 2017 Elsevier Ltd. All rights reserved.
40 CFR 63.4530 - What records must I keep?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Standards for Hazardous Air Pollutants for Surface Coating of Plastic Parts and Products Notifications... mass of organic HAP emission reduction by emission capture systems and add-on control devices using...
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.
NASA Astrophysics Data System (ADS)
Ueda, Yoshihiro; Suzuki, Yasumitsu; Watanabe, Kazuyuki
2018-02-01
Angle-resolved secondary electron emission (ARSEE) spectra were analyzed for two-dimensional atomic sheets using a time-dependent first-principles simulation of electron scattering. We demonstrate that the calculated ARSEE spectra capture the unoccupied band structure of the atomic sheets. The excitation dynamics that lead to SEE have also been revealed by the time-dependent Kohn-Sham decomposition scheme. In the present study, the mechanism for the experimentally observed ARSEE from atomic sheets is elucidated with respect to both energetics and the dynamical aspects of SEE.
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.
A plume capture technique for the remote characterization of aircraft engine emissions.
Johnson, G R; Mazaheri, M; Ristovski, Z D; Morawska, L
2008-07-01
A technique for capturing and analyzing plumes from unmodified aircraft or other combustion sources under real world conditions is described and applied to the task of characterizing plumes from commercial aircraft during the taxiing phase of the Landing/Take-Off (LTO) cycle. The method utilizes a Plume Capture and Analysis System (PCAS) mounted in a four-wheel drive vehicle which is positioned in the airfield 60 to 180 m downwind of aircraft operations. The approach offers low test turnaround times with the ability to complete careful measurements of particle and gaseous emission factors and sequentially scanned particle size distributions without distortion due to plume concentration fluctuations. These measurements can be performed for individual aircraft movements at five minute intervals. A Plume Capture Device (PCD) collected samples of the naturally diluted plume in a 200 L conductive membrane conforming to a defined shape. Samples from over 60 aircraft movements were collected and analyzed in situ for particulate and gaseous concentrations and for particle size distribution using a Scanning Particle Mobility Sizer (SMPS). Emission factors are derived for particle number, NO(x), and PM2.5 for a widely used commercial aircraft type, Boeing 737 airframes with predominantly CFM56 class engines, during taxiing. The practical advantages of the PCAS include the capacity to perform well targeted and controlled emission factor and size distribution measurements using instrumentation with varying response times within an airport facility, in close proximity to aircraft during their normal operations.
NASA Astrophysics Data System (ADS)
Chance, K.
2017-12-01
TEMPO is the first NASA Earth Venture Instrument. It launches between 2019 and 2021 to measure atmospheric pollution from Mexico City and Cuba to the Canadian oil sands, and from the Atlantic to the Pacific, hourly at high spatial resolution, 10 km2. Geostationary daytime measurements capture the variability in the diurnal cycle of emissions and chemistry at sub-urban scale to improve emission inventories, monitor population exposure, and enable emission-control strategies.TEMPO measures UV/visible Earth reflectance spectra to retrieve O3, NO2, SO2, H2CO, C2H2O2, H2O, BrO, OClO, IO, aerosols, cloud parameters, and UVB radiation. It tracks aerosol loading. It provides near-real-time air quality products. TEMPO is the North American component of the upcoming the global geostationary constellation for pollution monitoring, together with the European Sentinel-4 and the Korean Geostationary Environmental Monitoring Spectrometer (GEMS).TEMPO science studies include: Intercontinental pollution transport; Solar-induced fluorescence from chlorophyll over land and in the ocean to study tropical dynamics, primary productivity and carbon uptake, to detect red tides, and to study phytoplankton; measurements of stratospheric intrusions that cause air quality exceedances; measurements at peaks in vehicle travel to capture the variability in emissions from mobile sources; measurements of thunderstorm activity, including outflow regions to better quantify lightning NOx and O3 production; cropland measurements to follow the temporal evolution of emissions after fertilizer application and from rain-induced emissions from semi-arid soils; investigating the chemical processing of primary fire emissions and the secondary formation of VOCs and ozone; examining ocean halogen emissions and their impact on the oxidizing capacity of coastal environments; measuring spectra of nighttime lights as markers for human activity, energy conservation, and compliance with outdoor lighting standards intended to reduce light pollution.TEMPO provides much of the atmospheric measurement capability recommended for GEO-CAPE in the 2007 National Research Council Decadal Survey, Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond.
Tuning Fluorescence Direction with Plasmonic Metal–Dielectric– Metal Substrates
Choudhury, Sharmistha Dutta; Badugu, Ramachandram; Nowaczyk, Kazimierz; Ray, Krishanu; Lakowicz, Joseph R.
2013-01-01
Controlling the emission properties of fluorophores is essential for improving the performance of fluorescence-based techniques in modern biochemical research, medical diagnosis, and sensing. Fluorescence emission is isotropic in nature, which makes it difficult to capture more than a small fraction of the total emission. Metal– dielectric–metal (MDM) substrates, discussed in this Letter, convert isotropic fluorescence into beaming emission normal to the substrate. This improves fluorescence collection efficiency and also opens up new avenues for a wide range of fluorescence-based applications. We suggest that MDM substrates can be readily adapted for multiple uses, such as in microarray formats, for directional fluorescence studies of multiple probes or for molecule-specific sensing with a high degree of spatial control over the fluorescence emission. SECTION: Physical Processes in Nanomaterials and Nanostructures PMID:24013521
Secondary electron emission from textured surfaces
NASA Astrophysics Data System (ADS)
Huerta, C. E.; Patino, M. I.; Wirz, R. E.
2018-04-01
In this work, a Monte Carlo model is used to investigate electron induced secondary electron emission for varying effects of complex surfaces by using simple geometric constructs. Geometries used in the model include: vertical fibers for velvet-like surfaces, tapered pillars for carpet-like surfaces, and a cage-like configuration of interlaced horizontal and vertical fibers for nano-structured fuzz. The model accurately captures the secondary electron emission yield dependence on incidence angle. The model shows that unlike other structured surfaces previously studied, tungsten fuzz exhibits secondary electron emission yield that is independent of primary electron incidence angle, due to the prevalence of horizontally-oriented fibers in the fuzz geometry. This is confirmed with new data presented herein of the secondary electron emission yield of tungsten fuzz at incidence angles from 0-60°.
Code of Federal Regulations, 2012 CFR
2012-07-01
... capture system and add-on control device operating limits during the performance test? 63.4167 Section 63... capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.4092 according to this section unless you have received approval...
Code of Federal Regulations, 2014 CFR
2014-07-01
... capture system and add-on control device operating limits during the performance test? 63.4167 Section 63... capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.4092 according to this section unless you have received approval...
Code of Federal Regulations, 2014 CFR
2014-07-01
... capture system and add-on control device operating limits during the performance test? 63.4767 Section 63... capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.4692 according to this section, unless you have received...
Code of Federal Regulations, 2012 CFR
2012-07-01
... capture system and add-on control device operating limits during the performance test? 63.4767 Section 63... capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.4692 according to this section, unless you have received...
Reducing the cost of Ca-based direct air capture of CO2.
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.
Tuning the photon statistics of a strongly coupled nanophotonic system
NASA Astrophysics Data System (ADS)
Dory, Constantin; Fischer, Kevin A.; Müller, Kai; Lagoudakis, Konstantinos G.; Sarmiento, Tomas; Rundquist, Armand; Zhang, Jingyuan L.; Kelaita, Yousif; Sapra, Neil V.; Vučković, Jelena
2017-02-01
We investigate the dynamics of single- and multiphoton emission from detuned strongly coupled systems based on the quantum-dot-photonic-crystal resonator platform. Transmitting light through such systems can generate a range of nonclassical states of light with tunable photon counting statistics due to the nonlinear ladder of hybridized light-matter states. By controlling the detuning between emitter and resonator, the transmission can be tuned to strongly enhance either single- or two-photon emission processes. Despite the strongly dissipative nature of these systems, we find that by utilizing a self-homodyne interference technique combined with frequency filtering we are able to find a strong two-photon component of the emission in the multiphoton regime. In order to explain our correlation measurements, we propose rate equation models that capture the dominant processes of emission in both the single- and multiphoton regimes. These models are then supported by quantum-optical simulations that fully capture the frequency filtering of emission from our solid-state system.
40 CFR 63.3542 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2013 CFR
2013-07-01
... applicable emission limit in § 63.3490. Alternatively, if you calculate an OSEL for all coating type segments... of startup, shutdown, or malfunction of the emission capture system, add-on control device, or... Administrator will determine whether deviations that occur during a period you identify as a startup, shutdown...
40 CFR 63.3542 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2014 CFR
2014-07-01
... applicable emission limit in § 63.3490. Alternatively, if you calculate an OSEL for all coating type segments... of startup, shutdown, or malfunction of the emission capture system, add-on control device, or... Administrator will determine whether deviations that occur during a period you identify as a startup, shutdown...
Tzanidakis, Konstantinos; Oxley, Tim; Cockerill, Tim; ApSimon, Helen
2013-06-01
Integrated Assessment, and the development of strategies to reduce the impacts of air pollution, has tended to focus only upon the direct emissions from different sources, with the indirect emissions associated with the full life-cycle of a technology often overlooked. Carbon Capture and Storage (CCS) reflects a number of new technologies designed to reduce CO2 emissions, but which may have much broader environmental implications than greenhouse gas emissions. This paper considers a wider range of pollutants from a full life-cycle perspective, illustrating a methodology for assessing environmental impacts using source-apportioned effects based impact factors calculated by the national scale UK Integrated Assessment Model (UKIAM). Contrasting illustrative scenarios for the deployment of CCS towards 2050 are presented which compare the life-cycle effects of air pollutant emissions upon human health and ecosystems of business-as-usual, deployment of CCS and widespread uptake of IGCC for power generation. Together with estimation of the transboundary impacts we discuss the benefits of an effects based approach to such assessments in relation to emissions based techniques. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Ullmann, J. L.; Mosby, S.; Bredeweg, T. A.; Couture, A. J.; Haight, R. C.; Jandel, M.; Kawano, T.; O'Donnell, J. M.; Rundberg, R. S.; Vieira, D. J.; Wilhelmy, J. B.; Wu, C.-Y.; Becker, J. A.; Chyzh, A.; Baramsai, B.; Mitchell, G. E.; Krticka, M.
2014-05-01
A new measurement of the 238U(n, γ) cross section using a thin 48 mg/cm2 target was made using the DANCE detector at LANSCE over the energy range from 10 eV to 500 keV. The results confirm earlier measurements. Measurements of the gamma-ray emission spectra were also made for 238U(n, γ) as well as 234,236U(n, γ). These measurements help to constrain the radiative strength function used in the cross-section calculations.
Phonon-assisted changes in charge states of deep level defects in germanium
NASA Astrophysics Data System (ADS)
Markevich, A. V.; Litvinov, V. V.; Emtsev, V. V.; Markevich, V. P.; Peaker, A. R.
2006-04-01
Electronic processes associated with changes in the charge states of the vacancy-oxygen center (VO or A center) and vacancy-group-V-impurity atom (P, As, Sb or Bi) pairs (E centers) in irradiated germanium crystals have been studied using deep level transient spectroscopy (DLTS), high-resolution Laplace DLTS and Hall effect measurements. It is found that the electron emission and capture processes related to transitions between the doubly and the singly negatively charged states of the A center and the E centers in Ge are phonon-assisted, i.e., they are accompanied by significant vibrations and re-arrangements of atoms in the vicinity of the defects. Manifestations of the phonon involvements are: (i) temperature-dependent electron capture cross-sections which are well described in the frame of the multi-phonon-assisted capture model; (ii) large changes in entropy related to the ionization of the defects and, associated with these, temperature-dependent positions of energy levels; and (iii) electron emission via phonon-assisted tunneling upon the application of electric field. These effects have been considered in detail for the vacancy-oxygen and the vacancy-donor complexes. On the basis of a combined analysis of the electronic processes a configuration-coordinate diagram of the acceptor states of the A and E centers is plotted. It is found that changes in the entropy of ionization and the energy for electron emission for these traps follow the empirical Meyer-Neldel rule. A model based on multi-phonon-assisted carrier emission from defects is adapted for the explanation of the origin of this rule for the case of electronic processes in Ge.
Rightsizing expectations for carbon dioxide removal towards ambitious climate goals
NASA Astrophysics Data System (ADS)
Mach, K. J.; Field, C. B.
2017-12-01
Proven approaches for reducing heat-trapping emissions are increasingly cost competitive and feasible at scale. Such approaches include renewable-energy technologies, energy efficiency, reduced deforestation, and abatement of industrial and agricultural emissions. Their pace of deployment, though, is far from sufficient to limit warming well below 2°C above preindustrial levels, the goal of the Paris Agreement. Against this backdrop, technologies for carbon removal are increasingly asserted as key to climate policy. Carbon dioxide removal (CDR), or negative emissions, technologies can compensate for ongoing emissions, helping keep ambitious warming limits in reach. The dramatic rise of CDR approaches in analysis and planning towards ambitious climate goals, however, has stirred up discomfort and debate. Focusing on rightsizing CDR expectations, this presentation will first briefly reflect on the status of the suite of CDR possibilities. The options include strategies grounded in improved ecosystem stewardship (e.g., reforestation and afforestation, conservation agriculture); strategies that are also biomass-based but with more engineering and more trade-offs (e.g., biochar additions to soils, bioenergy with carbon capture and storage); and engineered, nonbiological approaches (e.g., enhanced weathering, direct air capture). Second, the presentation will evaluate constraints surrounding CDR deployment at large scale and in peak-and-decline scenarios. These constraints involve, for example, unprecedented rates of land transformation in climate change mitigation pathways limiting warming to 2°C with high probability. They also entail the substantial, little studied risks of scenarios with temperatures peaking and then declining. Third, the presentation will review emerging lessons from CDR implementation to date, such as in legally enforceable forest-offset projects, along with near-term opportunities for catalyzing CDR, such as through low-cost opportunities for carbon capture and storage.
Guidobaldi, F; Guerenstein, P G
2016-07-01
Triatomines, vectors of Chagas Disease, are hematophagous insects. Efforts have been made to develop synthetic attractants based on vertebrate odor-to lure them into traps. However, because those lures are not practical or have low capture efficiency, they are not in use in control programs. Therefore, more work is needed to reach a practical and efficient odor lure. Recently, a three-component, CO 2 -free, synthetic blend of vertebrate odor (consisting of ammonia, l-(+)-lactic acid, and hexanoic acid), known as Sweetscent (Biogents AG, Regensburg, Germany), was shown to attract and capture triatomines in the laboratory. In this study, using a trap olfactometer and an odor blend with constituents similar to those of Sweetscent (delivered from low-density polyethylene sachets) we found that the odorant ratios of the mixtures have a strong effect in the capture of triatomines. The blend with the most efficient combination of odorant ratios evoked ca. 81% capture in two relevant triatomine species. In the case of the most effective odor mixtures, we measured the odor mass emission for the three components of the mixture and therefore were able to estimate the odorant ratios emitted that were responsible for such a high capture performance. Thus, in those mixtures, pentanoic acid was the main component (ca. 65 %) followed by ammonia (ca. 28%) and, l(+)-lactic acid (ca. 7 %). Our results are encouraging as efficient, practical, and cheap odor baits to trap triatomines in the field would be within reach. The odor-delivery system used should be improved to increase stability of odor emission. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Dynamics of Postcombustion CO2 Capture Plants: Modeling, Validation, and Case Study
2017-01-01
The capture of CO2 from power plant flue gases provides an opportunity to mitigate emissions that are harmful to the global climate. While the process of CO2 capture using an aqueous amine solution is well-known from experience in other technical sectors (e.g., acid gas removal in the gas processing industry), its operation combined with a power plant still needs investigation because in this case, the interaction with power plants that are increasingly operated dynamically poses control challenges. This article presents the dynamic modeling of CO2 capture plants followed by a detailed validation using transient measurements recorded from the pilot plant operated at the Maasvlakte power station in the Netherlands. The model predictions are in good agreement with the experimental data related to the transient changes of the main process variables such as flow rate, CO2 concentrations, temperatures, and solvent loading. The validated model was used to study the effects of fast power plant transients on the capture plant operation. A relevant result of this work is that an integrated CO2 capture plant might enable more dynamic operation of retrofitted fossil fuel power plants because the large amount of steam needed by the capture process can be diverted rapidly to and from the power plant. PMID:28413256
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
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
Soft x-ray emission from solar wind charge exchange in the laboratory
NASA Astrophysics Data System (ADS)
Shimaya, H.; Ishida, T.; Ishikawa, S.; Suda, S.; Tanuma, H.; Akamatsu, H.; Ohashi, H.; Ijima, N.; Inoue, M.; Ezoe, Y.; Ishisaki, Y.; Ohashi, T.; Shinozaki, K.; Mitsuda, K.; Liu, L.; Wang, J.
2013-09-01
We have observed the emission spectra in collisions of bare oxygen ions with a helium gas target in the soft x-ray region with a window-less silicon drift detector at the collision energy range of 48-80 keV. The dominant soft x-ray emission corresponds to the 1s-2p transition of hydrogen-like oxygen O7+ produced by the single-electron charge exchange reaction. Other emission lines are the 1s-3p, 1s-4p and 1s-5p transitions of O7+, and also the 1s2-1s2p transition of O6+ produced by the true double-electron capture. The cascades from the upper states result in a large population of the 2p state, even though the direct capture into the 2p state is extremely scarcer than those into the 3p, 4p and 5p states.
NASA Astrophysics Data System (ADS)
Tsia, J. M.; Ling, C. C.; Beling, C. D.; Fung, S.
2002-09-01
A plus-or-minus100 V square wave applied to a Au/semi-insulating SI-GaAs interface was used to bring about electron emission from and capture into deep level defects in the region adjacent to the interface. The electric field transient resulting from deep level emission was studied by monitoring the positron drift velocity in the region. A deep level transient spectrum was obtained by computing the trap emission rate as a function of temperature and two peaks corresponding to EL2 (Ea=0.81plus-or-minus0.15 eV) and EL6 (Ea=0.30plus-or-minus0.12 eV) have been identified.
Soil carbon sequestration and biochar as negative emission technologies.
Smith, Pete
2016-03-01
Despite 20 years of effort to curb emissions, greenhouse gas (GHG) emissions grew faster during the 2000s than in the 1990s, which presents a major challenge for meeting the international goal of limiting warming to <2 °C relative to the preindustrial era. Most recent scenarios from integrated assessment models require large-scale deployment of negative emissions technologies (NETs) to reach the 2 °C target. A recent analysis of NETs, including direct air capture, enhanced weathering, bioenergy with carbon capture and storage and afforestation/deforestation, showed that all NETs have significant limits to implementation, including economic cost, energy requirements, land use, and water use. In this paper, I assess the potential for negative emissions from soil carbon sequestration and biochar addition to land, and also the potential global impacts on land use, water, nutrients, albedo, energy and cost. Results indicate that soil carbon sequestration and biochar have useful negative emission potential (each 0.7 GtCeq. yr(-1) ) and that they potentially have lower impact on land, water use, nutrients, albedo, energy requirement and cost, so have fewer disadvantages than many NETs. Limitations of soil carbon sequestration as a NET centre around issues of sink saturation and reversibility. Biochar could be implemented in combination with bioenergy with carbon capture and storage. Current integrated assessment models do not represent soil carbon sequestration or biochar. Given the negative emission potential of SCS and biochar and their potential advantages compared to other NETs, efforts should be made to include these options within IAMs, so that their potential can be explored further in comparison with other NETs for climate stabilization. © 2016 John Wiley & Sons Ltd.
Concina, Bruno; Baguenard, Bruno; Calvo, Florent; Bordas, Christian
2010-03-14
The delayed electron emission from small mass-selected anionic tungsten clusters W(n)(-) has been studied for sizes in the range 9 < or = n < or = 21. Kinetic energy spectra have been measured for delays of about 100 ns after laser excitation by a velocity-map imaging spectrometer. They are analyzed in the framework of microreversible statistical theories. The low-energy behavior shows some significant deviations with respect to the classical Langevin capture model, which we interpret as possibly due to the influence of quantum dynamical effects such as tunneling through the centrifugal barrier, rather than shape effects. The cluster temperature has been extracted from both the experimental kinetic energy spectrum and the absolute decay rate. Discrepancies between the two approaches suggest that the sticking probability can be as low as a few percent for the smallest clusters.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Benson, Steven; Palo, Daniel; Srinivasachar, Srivats
2014-12-01
Under contract DE-FE0007603, the University of North Dakota conducted the project Evaluation of Carbon Dioxide Capture from Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents. As an important element of this effort, an Environmental Health and Safety (EH&S) Assessment was conducted by Barr Engineering Co. (Barr) in association with the University of North Dakota. The assessment addressed air and particulate emissions as well as solid and liquid waste streams. The magnitude of the emissions and waste streams was estimated for evaluation purposes. EH&S characteristics of materials used in the system are also described. This document contains data basedmore » on the mass balances from both the 40 kJ/mol CO2 and 80 kJ/mol CO2 desorption energy cases evaluated in the Final Technical and Economic Feasibility study also conducted by Barr Engineering.« less
Improved defect analysis of Gallium Arsenide solar cells using image enhancement
NASA Technical Reports Server (NTRS)
Kilmer, Louis C.; Honsberg, Christiana; Barnett, Allen M.; Phillips, James E.
1989-01-01
A new technique has been developed to capture, digitize, and enhance the image of light emission from a forward biased direct bandgap solar cell. Since the forward biased light emission from a direct bandgap solar cell has been shown to display both qualitative and quantitative information about the solar cell's performance and its defects, signal processing techniques can be applied to the light emission images to identify and analyze shunt diodes. Shunt diodes are of particular importance because they have been found to be the type of defect which is likely to cause failure in a GaAs solar cell. The presence of a shunt diode can be detected from the light emission by using a photodetector to measure the quantity of light emitted at various current densities. However, to analyze how the shunt diodes affect the quality of the solar cell the pattern of the light emission must be studied. With the use of image enhancement routines, the light emission can be studied at low light emission levels where shunt diode effects are dominant.
Atmospheric inverse modeling via sparse reconstruction
NASA Astrophysics Data System (ADS)
Hase, Nils; Miller, Scot M.; Maaß, Peter; Notholt, Justus; Palm, Mathias; Warneke, Thorsten
2017-10-01
Many applications in atmospheric science involve ill-posed inverse problems. A crucial component of many inverse problems is the proper formulation of a priori knowledge about the unknown parameters. In most cases, this knowledge is expressed as a Gaussian prior. This formulation often performs well at capturing smoothed, large-scale processes but is often ill equipped to capture localized structures like large point sources or localized hot spots. Over the last decade, scientists from a diverse array of applied mathematics and engineering fields have developed sparse reconstruction techniques to identify localized structures. In this study, we present a new regularization approach for ill-posed inverse problems in atmospheric science. It is based on Tikhonov regularization with sparsity constraint and allows bounds on the parameters. We enforce sparsity using a dictionary representation system. We analyze its performance in an atmospheric inverse modeling scenario by estimating anthropogenic US methane (CH4) emissions from simulated atmospheric measurements. Different measures indicate that our sparse reconstruction approach is better able to capture large point sources or localized hot spots than other methods commonly used in atmospheric inversions. It captures the overall signal equally well but adds details on the grid scale. This feature can be of value for any inverse problem with point or spatially discrete sources. We show an example for source estimation of synthetic methane emissions from the Barnett shale formation.
AVERT captures the actual historical behavior of electricity generating units' (EGUs’) operation on an hourly basis to predict how EGUs will operate with additional EE/RE delivered to the electricity grid.
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.
Swift captures the spectrally evolving prompt emission of GRB070616
NASA Astrophysics Data System (ADS)
Starling, R. L. C.; O'Brien, P. T.; Willingale, R.; Page, K. L.; Osborne, J. P.; de Pasquale, M.; Nakagawa, Y. E.; Kuin, N. P. M.; Onda, K.; Norris, J. P.; Ukwatta, T. N.; Kodaka, N.; Burrows, D. N.; Kennea, J. A.; Page, M. J.; Perri, M.; Markwardt, C. B.
2008-02-01
The origins of gamma-ray burst (GRB) prompt emission are currently not well understood and in this context long, well-observed events are particularly important to study. We present the case of GRB070616, analysing the exceptionally long-duration multipeaked prompt emission, and later afterglow, captured by all the instruments on-board Swift and by Suzaku Wide-Band All-Sky Monitor (WAM). The high-energy light curve remained generally flat for several hundred seconds before going into a steep decline. Spectral evolution from hard to soft is clearly taking place throughout the prompt emission, beginning at 285s after the trigger and extending to 1200s. We track the movement of the spectral peak energy, whilst observing a softening of the low-energy spectral slope. The steep decline in flux may be caused by a combination of this strong spectral evolution and the curvature effect. We investigate origins for the spectral evolution, ruling out a superposition of two power laws and considering instead an additional component dominant during the late prompt emission. We also discuss origins for the early optical emission and the physics of the afterglow. The case of GRB070616 clearly demonstrates that both broad-band coverage and good time resolution are crucial to pin down the origins of the complex prompt emission in GRBs. This paper is dedicated to the memory of Dr Francesca Tamburelli who died during its production. Francesca played a fundamental role within the team which is in charge of the development of the Swift X-Ray Telescope (XRT) data analysis software at the Italian Space Agency's Science Data Centre in Frascati. She is sadly missed. E-mail: rlcs1@star.le.ac.uk
Environmental issues and process risks for operation of carbon capture plant
NASA Astrophysics Data System (ADS)
Lajnert, Radosław; Nowak, Martyna; Telenga-Kopyczyńska, Jolanta
2018-01-01
The scope of this publication is a presentation of environmental issues and process risks connected with operation an installation for carbon capture from waste gas. General technological assumptions, typical for demonstration plant for carbon capture from waste gas (DCCP) with application of two different solutions - 30% water solution of monoethanoloamine (MEA) and water solution with 30% AMP (2-amino-2-methyl-1-propanol) and 10% piperazine have been described. The concept of DCCP installation was made for Łaziska Power Plant in Łaziska Górne owned by TAURON Wytwarzanie S.A. Main hazardous substances, typical for such installation, which can be dangerous for human life and health or for the environment have been presented. Pollution emission to the air, noise emission, waste water and solid waste management have been described. The environmental impact of the released substances has been stated. Reference to emission standards specified in regulations for considered substances has been done. Principles of risk analysis have been presented and main hazards in carbon dioxide absorption node and regeneration node have been evaluated.
NASA Astrophysics Data System (ADS)
VanderZaag, A. C.; MacDonald, J. D.; Evans, L.; Vergé, X. P. C.; Desjardins, R. L.
2013-09-01
Methane emissions from manure management represent an important mitigation opportunity, yet emission quantification methods remain crude and do not contain adequate detail to capture changes in agricultural practices that may influence emissions. Using the Canadian emission inventory methodology as an example, this letter explores three key aspects for improving emission quantification: (i) obtaining emission measurements to improve and validate emission model estimates, (ii) obtaining more useful activity data, and (iii) developing a methane emission model that uses the available farm management activity data. In Canada, national surveys to collect manure management data have been inconsistent and not designed to provide quantitative data. Thus, the inventory has not been able to accurately capture changes in management systems even between manure stored as solid versus liquid. To address this, we re-analyzed four farm management surveys from the past decade and quantified the significant change in manure management which can be linked to the annual agricultural survey to create a continuous time series. In the dairy industry of one province, for example, the percentage of manure stored as liquid increased by 300% between 1991 and 2006, which greatly affects the methane emission estimates. Methane emissions are greatest from liquid manure, but vary by an order of magnitude depending on how the liquid manure is managed. Even if more complete activity data are collected on manure storage systems, default Intergovernmental Panel on Climate Change (IPCC) guidance does not adequately capture the impacts of management decisions to reflect variation among farms and regions in inventory calculations. We propose a model that stays within the IPCC framework but would be more responsive to farm management by generating a matrix of methane conversion factors (MCFs) that account for key factors known to affect methane emissions: temperature, retention time and inoculum. This MCF matrix would be populated using a mechanistic emission model verified with on-farm emission measurements. Implementation of these MCF values will require re-analysis of farm surveys to quantify liquid manure emptying frequency and timing, and will rely on the continued collection of this activity data in the future. For model development and validation, emission measurement campaigns will be needed on representative farms over at least one full year, or manure management cycle (whichever is longer). The proposed approach described in this letter is long-term, but is required to establish baseline data for emissions from manure management systems. With these improvements, the manure management emission inventory will become more responsive to the changing practices on Canadian livestock farms.
Vulnerability of United States Bridges to Potential Increases in Flooding from Climate Change
This study assesses the potential impacts of increased river flooding from climate change on bridges in the continental United States. Daily precipitation statistics from four climate models and three greenhouse gas (GHG) emissions scenarios (A2, A1B, and B1) are used to capture ...
VOC/HAP control systems for the shipbuilding and aerospace industries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lukey, M.E.; Toothman, D.A.
1999-07-01
Compliant coating systems, i.e., those which meet limits on pounds of volatile organic compound (VOC)/hazardous air pollutant (HAP) per gallon, on a solids applied basis, are routinely used to meet emission regulations in the shipbuilding and aerospace industries. However, there are occasions when solvent based systems must be used. Total capture and high destruction of the solvents in those systems is necessary in order to meet the required emission limit, e.g., a reasonably available control technology (RACT) limit of 3.5lbs of VOC/gallon. Water based marine coatings and certain aerospace finish coats do not provide sufficient longevity or meet other customermore » specifications in these instances. Furthermore, because of best available control technology (BACT) determinations or facility limits for operation in serious, severe, and extreme nonattainment areas, it is necessary to reduce annual emissions to levels which are below the levels required by the coating standards. The paper discusses those operations for controlling emissions from large-scale solvent based painting and coating systems in those instances when a high degree of overall control is required. Permanent total enclosures (stationary and portable), concentrators, regenerative thermal oxidizers, and other air pollution control systems are evaluated, both for technical applicability and economic feasibility. Several case studies are presented which illustrate techniques for capturing painting emissions, options for air handling in the workplace, and methods for destroying exhaust stream VOC concentrations of less than 40 ppm.« less
Computational Modeling of the Geologic Sequestration of Carbon Dioxide
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...
40 CFR 63.4765 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2014 CFR
2014-07-01
... determination, substitute TVH for each occurrence of the term volatile organic compounds (VOC) in the methods... organic compound emitting operations inside the building enclosure, other than the coating operation for... the capture efficiency measurement, all organic compound emitting operations inside the building...
40 CFR 63.4765 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2012 CFR
2012-07-01
... determination, substitute TVH for each occurrence of the term volatile organic compounds (VOC) in the methods... organic compound emitting operations inside the building enclosure, other than the coating operation for... the capture efficiency measurement, all organic compound emitting operations inside the building...
Laboratory experiments on soft x-ray emissions from the solar wind
NASA Astrophysics Data System (ADS)
Kanda, T.; Ohashi, H.; Maeno, S.; Ishida, T.; Tanuma, H.; Akamatsu, H.; Abe, Y.; Yokota, W.; Henmi, K.; Ishisaki, Y.; Ezoe, Y.; Ohashi, T.; Shinozaki, K.; Mitsuda, K.
2011-06-01
We have observed emission spectra in collisions of hydrogen-like oxygen and nitrogen ions with a helium target gas in the soft x-ray region using a window-less Si(Li) detector at collision energies of about 100 keV. The dominant soft x-ray emission is the 1s2-1s2p transition of helium-like ions produced by a single-electron capture reaction. We indicate that the cascades from the upper states give a large population of the 2p state, even though direct capture into the 2p state is much smaller than the 3ell and 4ell states. The intensity ratios of the 1s-2p and 1s-3p transitions are discussed, along with a comparison with the theoretical calculation.
Cocker, David R; Shah, Sandip D; Johnson, Kent; Miller, J Wayne; Norbeck, Joseph M
2004-04-01
Information about in-use emissions from diesel engines remains a critical issue for inventory development and policy design. Toward that end, we have developed and verified the first mobile laboratory that measures on-road or real-world emissions from engines at the quality level specified in the U.S. Congress Code of Federal Regulations. This unique mobile laboratory provides information on integrated and modal regulated gaseous emission rates and integrated emission rates for speciated volatile and semivolatile organic compounds and particulate matter during real-world operation. Total emissions are captured and collected from the HDD vehicle that is pulling the mobile laboratory. While primarily intended to accumulate data from HDD vehicles, it may also be used to measure emission rates from stationary diesel sources such as back-up generators. This paper describes the development of the mobile laboratory, its measurement capabilities, and the verification process and provides the first data on total capture gaseous on-road emission measurements following the California Air Resources Board (ARB) 4-mode driving cycle, the hot urban dynamometer driving schedule (UDDS), the modified 5-mode cycle, and a 53.2-mi highway chase experiment. NOx mass emission rates (g mi(-1)) for the ARB 4-mode driving cycle, the hot UDDS driving cycle, and the chase experimentwerefoundto exceed current emission factor estimates for the engine type tested by approximately 50%. It was determined that congested traffic flow as well as "off-Federal Test Procedure cycle" emissions can lead to significant increases in per mile NOx emission rates for HDD vehicles.
Evaluation of On-Road Vehicle Emission Trends in the United States
NASA Astrophysics Data System (ADS)
Harley, R. A.; Dallmann, T. R.; Kirchstetter, T.
2010-12-01
Mobile sources contribute significantly to emissions of nitrogen oxides (NOx), carbon monoxide (CO), fine particulate matter (PM2.5), and black carbon (BC). These emissions lead to a variety of environmental problems including air pollution and climate change. At present, national and state-level mobile source emission inventories are developed using statistical models to predict emissions from large and diverse populations of vehicles. Activity is measured by total vehicle-km traveled, and pollutant emission factors are predicted based on laboratory testing of individual vehicles. Despite efforts to improve mobile source emission inventories, they continue to have large associated uncertainties. Alternate methods, such as the fuel-based approach used here, are needed to evaluate estimates of mobile source emissions and to help reduce uncertainties. In this study we quantify U.S. national emissions of NOx, CO, PM2.5, and BC from on-road diesel and gasoline vehicles for the years 1990-2010, including effects of a weakened national economy on fuel sales and vehicle travel from 2008-10. Pollutant emissions are estimated by multiplying total amounts of fuel consumed with emission factors expressed per unit of fuel burned. Fuel consumption is used as a measure of vehicle activity, and is based on records of taxable fuel sales. Pollutant emission factors are derived from roadside and tunnel studies, remote sensing measurements, and individual vehicle exhaust plume capture experiments. Emission factors are updated with new results from a summer 2010 field study conducted at the Caldecott tunnel in the San Francisco Bay Area.
Synergistic Carbon Dioxide Capture and Conversion in Porous Materials.
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.
Radiative-emission analysis in charge-exchange collisions of O6 + with argon, water, and methane
NASA Astrophysics Data System (ADS)
Leung, Anthony C. K.; Kirchner, Tom
2017-04-01
Processes of electron capture followed by Auger and radiative decay were investigated in slow ion-atom and -molecule collisions. A quantum-mechanical analysis which utilizes the basis generator method within an independent electron model was carried out for collisions of O 6 + with Ar, H2O , and CH4 at impact energies of 1.17 and 2.33 keV/amu. At these impact energies, a closure approximation in the spectral representation of the Hamiltonian for molecules was found to be necessary to yield reliable results. Total single-, double-, and triple-electron-capture cross sections obtained show good agreement with previous measurements and calculations using the classical trajectory Monte Carlo method. The corresponding emission spectra from single capture for each collision system are in satisfactory agreement with previous calculations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roshchanka, Volha; Evans, Meredydd; Ruiz, Felicia
Coal production globally is projected to grow in the foreseeable future. Countries with heavy reliance on coal could reduce methane and other emissions through the capture and utilization of coal mine methane (CMM) in the short and medium term, while they pursue structural and long-term economic changes. Several countries have successfully implemented policies to promote CMM capture and utilization; however, some countries still struggle to implement projects. This paper outlines key factors to consider in adapting policies for CMM mitigation. The authors propose an approach for selecting adequate mechanisms for stimulating CMM mitigation that involves reviewing global best practices andmore » categorizing them functionally either as mechanisms needed to improve the underlying conditions or as CMM-specific policies. It is important to understand local policy frameworks and to consider whether it is more feasible to improve underlying policy conditions or to provide targeted incentives as an interim measure. Using Kazakhstan as a case study, the authors demonstrate how policymakers could assess the overall policy framework to find the most promising options to facilitate CMM projects. Kazakhstan’s emissions from underground coal mines have been increasing both in total and per tonne of coal production, while overall production has been declining. CMM mitigation presents an opportunity for the country to reduce its greenhouse gas emissions in the near and medium term, while the government pursues sustainable development goals. Analysis shows that policymakers in Kazakhstan can leverage existing policies to stimulate utilization by extending feed-in tariffs to cover CMM and by developing working methodologies for companies to obtain emission reduction credits from CMM projects.« less
40 CFR 63.4500 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
...) for which you use the compliant material option or the emission rate without add-on controls option... § 63.4490 at all times. (2) Any coating operation(s) for which you use the emission rate with add-on... for emission capture systems and add-on control devices required by § 63.4492 at all times except...
40 CFR 63.4500 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
...) for which you use the compliant material option or the emission rate without add-on controls option... § 63.4490 at all times. (2) Any coating operation(s) for which you use the emission rate with add-on... for emission capture systems and add-on control devices required by § 63.4492 at all times except...
40 CFR 63.3900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... operation(s) for which you use the compliant material option or the emission rate without add-on controls... § 63.3890 at all times. (2) Any coating operation(s) for which you use the emission rate with add-on... for emission capture systems and add-on control devices required by § 63.3892 at all times except...
40 CFR 63.4500 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
...) for which you use the compliant material option or the emission rate without add-on controls option... § 63.4490 at all times. (2) Any coating operation(s) for which you use the emission rate with add-on... for emission capture systems and add-on control devices required by § 63.4492 at all times except...
40 CFR 63.3900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... operation(s) for which you use the compliant material option or the emission rate without add-on controls... § 63.3890 at all times. (2) Any coating operation(s) for which you use the emission rate with add-on... for emission capture systems and add-on control devices required by § 63.3892 at all times except...
40 CFR 63.3900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... operation(s) for which you use the compliant material option or the emission rate without add-on controls... § 63.3890 at all times. (2) Any coating operation(s) for which you use the emission rate with add-on... for emission capture systems and add-on control devices required by § 63.3892 at all times except...
40 CFR 63.3900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
...) for which you use the compliant material option or the emission rate without add-on controls option... § 63.3890 at all times. (2) Any coating operation(s) for which you use the emission rate with add-on... for emission capture systems and add-on control devices required by § 63.3892 at all times except...
40 CFR 63.3900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
...) for which you use the compliant material option or the emission rate without add-on controls option... § 63.3890 at all times. (2) Any coating operation(s) for which you use the emission rate with add-on... for emission capture systems and add-on control devices required by § 63.3892 at all times except...
Code of Federal Regulations, 2010 CFR
2010-07-01
.... Group 1 furnace without add-on controls Fluxing in sidewell furnace hearth Maintain flux addition... emission units with an add-on air pollution control device Emission capture and collection system Annual... specifications, or at least once every 6 months. Group 1 furnace, group 2 furnace, in-line fluxer, and scrap...
Code of Federal Regulations, 2014 CFR
2014-07-01
...; certify every 6 months. Group 1 furnace without add-on controls Fluxing in sidewell furnace hearth... sources and emission units with an add-on air pollution control device Emission capture and collection... to manufacturers specifications, or at least once every 6 months. Group 1 furnace, group 2 furnace...
Novel method for on-road emission factor measurements using a plume capture trailer.
Morawska, L; Ristovski, Z D; Johnson, G R; Jayaratne, E R; Mengersen, K
2007-01-15
The method outlined provides for emission factor measurements to be made for unmodified vehicles driving under real world conditions at minimal cost. The method consists of a plume capture trailer towed behind a test vehicle. The trailer collects a sample of the naturally diluted plume in a 200 L conductive bag and this is delivered immediately to a mobile laboratory for subsequent analysis of particulate and gaseous emissions. The method offers low test turnaround times with the potential to complete much larger numbers of emission factor measurements than have been possible using dynamometer testing. Samples can be collected at distances up to 3 m from the exhaust pipe allowing investigation of early dilution processes. Particle size distribution measurements, as well as particle number and mass emission factor measurements, based on naturally diluted plumes are presented. A dilution profile relating the plume dilution ratio to distance from the vehicle tail pipe for a diesel passenger vehicle is also presented. Such profiles are an essential input for new mechanistic roadway air quality models.
Water impacts of CO2 emission performance standards for fossil fuel-fired power plants.
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.
Implementing microscopic charcoal in a global climate-aerosol model
NASA Astrophysics Data System (ADS)
Gilgen, Anina; Lohmann, Ulrike; Brügger, Sandra; Adolf, Carole; Ickes, Luisa
2017-04-01
Information about past fire activity is crucial to validate fire models and to better understand their deficiencies. Several paleofire records exist, among them ice cores and sediments, which preserve fire tracers like levoglucosan, vanillic acid, or charcoal particles. In this work, we implement microscopic charcoal particles (maximum dimension 10-100 μm) into the global climate-aerosol model ECHAM6.3HAM2.3. Since we are not aware of any reliable estimates of microscopic charcoal emissions, we scaled black carbon emissions from GFAS to capture the charcoal fluxes from a calibration dataset. After that, model results were compared with a validation dataset. The coarse model resolution (T63L31; 1.9°x1.9°) impedes the model to capture local variability of charcoal fluxes. However, variability on the global scale is pronounced due to highly-variable fire emissions. In future, we plan to model charcoal fluxes in the past 1-2 centuries using fire emissions provided from fire models. Furthermore, we intend to compare modelled charcoal fluxes from prescribed fire emissions with those calculated by an interactive fire model.
Geological Sequestration of CO2 A Brief Overview and Potential for Application for Oklahoma
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...
40 CFR 63.2292 - What definitions apply to this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... designed and maintained to capture all emissions for discharge through a control device. Work practice..., wheat straw, rice straw, and bagasse. Biofilter means an enclosed control system such as a tank or... collected by a capture device. Catalytic oxidizer means a control system that combusts or oxidizes, in the...
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.
IN-FLIGHT CAPTURE OF ELEMENTAL MERCURY BY A CHLORINE-IMPREGNATED ACTIVATED CARBON
The paper discusses the in-flight capture of elemental mercury (Hgo) by a chlorine (C1)-impregnated activated carbon. Efforts to develop sorbents for the control of Hg emissions have demonstrated that C1-impregnation of virgin activated carbons using dilute solutions of hydrogen ...
One innovative option for reducing greenhouse gas (GHG) emissions involves pairing carbon capture and storage (CCS) with the production of synthetic fuels and electricity from co-processed coal and biomass. In this scheme, the feedstocks are first converted to syngas, from which ...
40 CFR 63.1013 - Sampling connection systems standards.
Code of Federal Regulations, 2011 CFR
2011-07-01
... (CONTINUED) National Emission Standards for Equipment Leaks-Control Level 1 § 63.1013 Sampling connection... container are not required to be collected or captured. (c) Equipment design and operation. Each closed... process fluid to a process; or (3) Be designed and operated to capture and transport all the purged...
40 CFR 63.4565 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2014 CFR
2014-07-01
... occurrence of the term volatile organic compounds (VOC) in the methods. (3) Use Equation 1 of this section to... the capture efficiency measurement, all organic compound emitting operations inside the building... organic compound emitting operations inside the building enclosure, other than the coating operation for...
40 CFR 63.4565 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2012 CFR
2012-07-01
... occurrence of the term volatile organic compounds (VOC) in the methods. (3) Use Equation 1 of this section to... the capture efficiency measurement, all organic compound emitting operations inside the building... organic compound emitting operations inside the building enclosure, other than the coating operation for...
40 CFR 63.4565 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
... the term volatile organic compounds (VOC) in the methods. (3) Use Equation 1 of this section to... the capture efficiency measurement, all organic compound emitting operations inside the building... organic compound emitting operations inside the building enclosure, other than the coating operation for...
40 CFR 63.4565 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2013 CFR
2013-07-01
... the term volatile organic compounds (VOC) in the methods. (3) Use Equation 1 of this section to... the capture efficiency measurement, all organic compound emitting operations inside the building... organic compound emitting operations inside the building enclosure, other than the coating operation for...
40 CFR 63.3981 - What definitions apply to this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
..., activators, accelerators). Add-on control means an air pollution control device, such as a thermal oxidizer or carbon adsorber, that reduces pollution in an air stream by destruction or removal before... directing those emissions into an add-on air pollution control device. Capture efficiency or capture system...
NASA Astrophysics Data System (ADS)
Herdrich, M. O.; Weber, G.; Gumberidze, A.; Wu, Z. W.; Stöhlker, Th.
2017-10-01
In experiments with highly charged, fast heavy ions the Radiative Recombination (RR) and Radiative Electron Capture (REC) processes have significant cross sections in an energy range of up to a few GeV / u . They are some of the most important charge changing processes in collisions of heavy ions with atoms and electrons, leading to the emission of a photon along with the formation of the ground and excited atomic states. Hence, for the understanding and planning of experiments, in particular for X-ray spectroscopy studies, at accelerator ring facilities, such as FAIR, it is crucial to have a good knowledge of these cross sections and the associated radiation characteristics. In the frame of this work a fast calculator, named RECAL, for the RR and REC process is presented and its capabilities are demonstrated with the analysis of a recently conducted experiment at the Experimental Storage Ring (ESR) at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany. A method is presented to determine unknown X-ray emission cross sections via normalization of the recorded spectra to REC cross sections calculated by RECAL.
NASA Technical Reports Server (NTRS)
Perez-Peraza, J.; Alvarez, M.; Gallegos, A.
1985-01-01
Lower limits of photon fluxes were evaluated from electron capture during acceleration in solar flares, because the arbitrary q sub c asterisk assumed in this work evolves very slow with velocity, probably much more slowly than the physical actual situation: in fact, more emission is expected toward the IR region. Nevertheless the authors claim to show that the factibility of sounding acceleration processes, charge evolution processes and physical parameters of the source itself, by the observational analysis of this kind of emissions. For instance, it would be interesting to search observationally, for the predicted flux and energy drift of F sub e ions interacting with the atomic 0 and F sub e of the source matter, or, even more feasible for the X-ray lines at 4.2 keV and 2.624 + 0.003 KeV from Fe and S ions in ionized Fe at T = 10 to the 7th power K respectively, the 418 + or - 2 eV and 20 + or - 4 eV lines of Fe and S in ionized Fe at 5 x 10 to the 6th power K, which are predicted from Fermi acceleration.
Dynamics of vapor emissions at wire explosion thresholda)
NASA Astrophysics Data System (ADS)
Belony, Paul A.; Kim, Yong W.
2010-10-01
X-pinch plasmas have been actively studied in the recent years. Numerical simulation of the ramp-up of metallic vapor emissions from wire specimens shows that under impulsive Ohmic heating the wire core invariably reaches a supercritical state before explosion. The heating rate depends sensitively on the local wire resistance, leading to highly variable vapor emission flux along the wire. To examine the vapor emission process, we have visualized nickel wire explosions by means of shock formation in air. In a single explosion as captured by shadowgraphy, there usually appear several shocks with spherical or cylindrical wave front originating from different parts of the wire. Growth of various shock fronts in time is well characterized by a power-law scaling in one form or another. Continuum emission spectra are obtained and calibrated to measure temperature near the explosion threshold. Shock front structures and vapor plume temperature are examined.
NASA Astrophysics Data System (ADS)
Drew, G. H.; Smith, R.; Gerard, V.; Burge, C.; Lowe, M.; Kinnersley, R.; Sneath, R.; Longhurst, P. J.
Odour emissions are episodic, characterised by periods of high emission rates, interspersed with periods of low emissions. It is frequently the short term, high concentration peaks that result in annoyance in the surrounding population. Dispersion modelling is accepted as a useful tool for odour impact assessment, and two approaches can be adopted. The first approach of modelling the hourly average concentration can underestimate total odour concentration peaks, resulting in annoyance and complaints. The second modelling approach involves the use of short averaging times. This study assesses the appropriateness of using different averaging times to model the dispersion of odour from a landfill site. We also examine perception of odour in the community in conjunction with the modelled odour dispersal, by using community monitors to record incidents of odour. The results show that with the shorter averaging times, the modelled pattern of dispersal reflects the pattern of observed odour incidents recorded in the community monitoring database, with the modelled odour dispersing further in a north easterly direction. Therefore, the current regulatory method of dispersion modelling, using hourly averaging times, is less successful at capturing peak concentrations, and does not capture the pattern of odour emission as indicated by the community monitoring database. The use of short averaging times is therefore of greater value in predicting the likely nuisance impact of an odour source and in framing appropriate regulatory controls.
40 CFR 63.7800 - What are my operation and maintenance requirements?
Code of Federal Regulations, 2010 CFR
2010-07-01
... prepare and operate at all times according to a written operation and maintenance plan for each capture... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Integrated Iron and Steel...
40 CFR 63.7800 - What are my operation and maintenance requirements?
Code of Federal Regulations, 2011 CFR
2011-07-01
... prepare and operate at all times according to a written operation and maintenance plan for each capture... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Integrated Iron and Steel...
40 CFR 63.7800 - What are my operation and maintenance requirements?
Code of Federal Regulations, 2012 CFR
2012-07-01
... prepare and operate at all times according to a written operation and maintenance plan for each capture... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Integrated Iron and Steel...
40 CFR 63.7800 - What are my operation and maintenance requirements?
Code of Federal Regulations, 2013 CFR
2013-07-01
... prepare and operate at all times according to a written operation and maintenance plan for each capture... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Integrated Iron and Steel...
40 CFR 63.7800 - What are my operation and maintenance requirements?
Code of Federal Regulations, 2014 CFR
2014-07-01
... prepare and operate at all times according to a written operation and maintenance plan for each capture... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Integrated Iron and Steel...
40 CFR 64.3 - Monitoring design criteria.
Code of Federal Regulations, 2013 CFR
2013-07-01
... indicators of emission control performance for the control device, any associated capture system and, if.... Indicators of performance may include, but are not limited to, direct or predicted emissions (including...(s) or designated condition(s) for the selected indicator(s) such that operation within the ranges...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Janak, K.; Becker, G.; Colmisjoe, A.
1998-06-01
The presence of 24 methyl sulfonyl polychlorinated biphenyl (PCB) congeners (MeSO{sub 2}-CBs) and 3-methyl sulfonyl 2,2-bis(4-chlorophenyl)-1,1-dichlorethene (DDE) (MeSO{sub 2}-DDE), metabolites of PCB and DDE, in blubber, lung, and liver of gray seals has been determined by using atomic emission detection (AED) and electron capture detection (ECD). Selective accumulation of aryl methyl sulfones in blubber, liver, and lung tissue was also investigated. For the liver samples, a substantial and highly specific retention of PCB methyl sulfones was observed. The atomic emission technique significantly improved the determination of measured solutes compared with ECD. Atomic emission detection was also valuable for the monitoringmore » of the prefractionation and to decrease the requirements of sample clean-up. Comparing both detection techniques showed a good correlation between the results of the AED sulfur-selective line and ECD.« less
NASA Astrophysics Data System (ADS)
Civerolo, Kevin; Hogrefe, Christian; Zalewsky, Eric; Hao, Winston; Sistla, Gopal; Lynn, Barry; Rosenzweig, Cynthia; Kinney, Patrick L.
2010-10-01
This paper compares spatial and seasonal variations and temporal trends in modeled and measured concentrations of sulfur and nitrogen compounds in wet and dry deposition over an 18-year period (1988-2005) over a portion of the northeastern United States. Substantial emissions reduction programs occurred over this time period, including Title IV of the Clean Air Act Amendments of 1990 which primarily resulted in large decreases in sulfur dioxide (SO 2) emissions by 1995, and nitrogen oxide (NO x) trading programs which resulted in large decreases in warm season NO x emissions by 2004. Additionally, NO x emissions from mobile sources declined more gradually over this period. The results presented here illustrate the use of both operational and dynamic model evaluation and suggest that the modeling system largely captures the seasonal and long-term changes in sulfur compounds. The modeling system generally captures the long-term trends in nitrogen compounds, but does not reproduce the average seasonal variation or spatial patterns in nitrate.
Carbon Capture and Sequestration- A Review
NASA Astrophysics Data System (ADS)
Sood, Akash; Vyas, Savita
2017-08-01
The Drastic increase of CO2 emission in the last 30 years is due to the combustion of fossil fuels and it causes a major change in the environment such as global warming. In India, the emission of fossil fuels is developed in the recent years. The alternate energy sources are not sufficient to meet the values of this emission reduction and the framework of climate change demands the emission reduction, the CCS technology can be used as a mitigation tool which evaluates the feasibility for implementation of this technology in India. CCS is a process to capture the carbon dioxide from large sources like fossil fuel station to avoid the entrance of CO2 in the atmosphere. IPCC accredited this technology and its path for mitigation for the developing countries. In this paper, we present the technologies of CCS with its development and external factors. The main goal of this process is to avoid the release the CO2 into the atmosphere and also investigates the sequestration and mitigation technologies of carbon.
Characterization of Black Carbon Mixing State
Sedlacek, Arthur; S, Satheesh; Springston, Stephen
2013-11-06
This measurement characterizes the types of BC emissions that result in nearsurface BC containing particles in a region that is dominated by biomass and open pit/stove cooking. Specifically, examine three primary BC emission sources: (i) urban setting (e.g., fossil fuel emissions); and (ii) biomass burning. Source (i) are captured at the Indian Institute of Science (IISc) in Bangalore. Biomass emissions (ii) contains a series of 12 day measurement excursions to the rural area surrounding Bangalore.
Carbon dioxide capture from atmospheric air using sodium hydroxide spray.
Stolaroff, Joshuah K; Keith, David W; Lowry, Gregory V
2008-04-15
In contrast to conventional carbon capture systems for power plants and other large point sources, the system described in this paper captures CO2 directly from ambient air. This has the advantages that emissions from diffuse sources and past emissions may be captured. The objective of this research is to determine the feasibility of a NaOH spray-based contactor for use in an air capture system by estimating the cost and energy requirements per unit CO2 captured. A prototype system is constructed and tested to measure CO2 absorption, energy use, and evaporative water loss and compared with theoretical predictions. A numerical model of drop collision and coalescence is used to estimate operating parameters for a full-scale system, and the cost of operating the system per unit CO2 captured is estimated. The analysis indicates that CO2 capture from air for climate change mitigation is technically feasible using off-the-shelf technology. Drop coalescence significantly decreases the CO2 absorption efficiency; however, fan and pump energy requirements are manageable. Water loss is significant (20 mol H2O/mol CO2 at 15 degrees C and 65% RH) but can be lowered by appropriately designing and operating the system. The cost of CO2 capture using NaOH spray (excluding solution recovery and CO2 sequestration, which may be comparable) in the full-scale system is 96 $/ton-CO2 in the base case, and ranges from 53 to 127 $/ton-CO2 under alternate operating parameters and assumptions regarding capital costs and mass transfer rate. The low end of the cost range is reached by a spray with 50 microm mean drop diameter, which is achievable with commercially available spray nozzles.
NASA Astrophysics Data System (ADS)
Wang, Yi; Wang, Jun; Xu, Xiaoguang; Henze, Daven K.; Wang, Yuxuan; Qu, Zhen
2016-09-01
SO2 emissions, the largest source of anthropogenic aerosols, can respond rapidly to economic and policy driven changes. However, bottom-up SO2 inventories have inherent limitations owing to 24-48 months latency and lack of month-to-month variation in emissions (especially in developing countries). This study develops a new approach that integrates Ozone Monitoring Instrument (OMI) SO2 satellite measurements and GEOS-Chem adjoint model simulations to constrain monthly anthropogenic SO2 emissions. The approach's effectiveness is demonstrated for 14 months in East Asia; resultant posterior emissions not only capture a 20% SO2 emission reduction in Beijing during the 2008 Olympic Games but also improve agreement between modeled and in situ surface measurements. Further analysis reveals that posterior emissions estimates, compared to the prior, lead to significant improvements in forecasting monthly surface and columnar SO2. With the pending availability of geostationary measurements of tropospheric composition, we show that it may soon be possible to rapidly constrain SO2 emissions and associated air quality predictions at fine spatiotemporal scales.
40 CFR 63.4100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... compliant material option or the emission rate without add-on controls option, as specified in § 63.4091(a... coating operation(s) for which you use the emission rate with add-on controls option, as specified in § 63... operating limits for emission capture systems and add-on control devices required by § 63.4092 at all times...
40 CFR 63.4100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... compliant material option or the emission rate without add-on controls option, as specified in § 63.4091(a... coating operation(s) for which you use the emission rate with add-on controls option, as specified in § 63... operating limits for emission capture systems and add-on control devices required by § 63.4092 at all times...
40 CFR 63.4100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... corrective actions in the event of a malfunction of the emission capture system or the add-on control device... material option or the emission rate without add-on controls option, as specified in § 63.4091(a) and (b... operation(s) for which you use the emission rate with add-on controls option, as specified in § 63.4091(c...
40 CFR 63.4100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... corrective actions in the event of a malfunction of the emission capture system or the add-on control device... material option or the emission rate without add-on controls option, as specified in § 63.4091(a) and (b... operation(s) for which you use the emission rate with add-on controls option, as specified in § 63.4091(c...
40 CFR 63.4100 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... compliant material option or the emission rate without add-on controls option, as specified in § 63.4091(a... coating operation(s) for which you use the emission rate with add-on controls option, as specified in § 63... operating limits for emission capture systems and add-on control devices required by § 63.4092 at all times...
US Steel Gary Works land based pushing emissions control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Randolph, R.A.; Price, C.A.
1983-01-01
To meet air quality standards at its Gary Works Coke Plant in Gary, Indiana, US Steel Corporation has installed pushing emission control systems for its five (77) oven, three meter coke batteries. The pushing emission control system consists of a hooded coke guide, single spot catch car, stationary emission capture ducts and remote gas cleaning baghouse with precoat capabilities. The system is providing effective emission control. In addition, there are corollary benefits. The operation of the single spot catch cars is easier and safer and coke moisture variables have been reduced.
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.
Modeling and optimal design of CO2 Direct Air Capture systems in large arrays
NASA Astrophysics Data System (ADS)
Sadri Irani, Samaneh; Luzzatto-Fegiz, Paolo
2017-11-01
As noted by the 2014 IPCC report, while the rise in atmospheric CO2 would be slowed by emissions reductions, removing atmospheric CO2 is an important part of possible paths to climate stabilization. Direct Air Capture of CO2 with chemicals (DAC) is one of several proposed carbon capture technologies. There is an ongoing debate on whether DAC is an economically viable approach to alleviate climate change. In addition, like all air capture strategies, DAC is strongly constrained by the net-carbon problem, namely the need to control CO2 emissions associated with the capture process (for example, if DAC not powered by renewables). Research to date has focused on the chemistry and economics of individual DAC devices. However, the fluid mechanics of their large-scale deployment has not been examined in the literature, to the best of our knowledge. In this presentation, we develop a model for flow through an array of DAC devices, varying their lateral extent and their separation. We build on a recent theory of canopy flows, introducing terms for CO2 entrainment into the array boundary layer, and transport into the farm. In addition, we examine the possibility of driving flow passively by wind, thereby reducing energy consumption. The optimal operational design is established considering the total cost, drag force, energy consumption and total CO2 capture.
Black carbon in the Arctic: How well is it captured by models?
NASA Astrophysics Data System (ADS)
Eckhardt, Sabine
2015-04-01
A correct representation of the spatial distribution of aerosols in atmospheric models is essential for realistic simulations of deposition and calculations of radiative forcing. It has been observed that transport of black carbon (BC) into the Arctic and scavenging is sometimes not captured accurately enough in chemistry transport models (CTM) as well as global circulation models (GCM). In this study we determine the discrepancies between measured equivalent BC (EBC) and modeled BC for several Arctic measurement stations as well as for Arctic aircraft campaigns. For this, we use the output of a set of 11 models based on the same emission dataset (ECLIPSE emissions, see eclipse.nilu.no) and evaluate the simulated concentrations at the measurement locations and times. Emissions are separated for different sources such as biomass burning, domestic heating, gas flaring, industry and the transport sector. We focus on the years 2008 and 2009, where many campaigns took place in the framework of the International Polar Year. Arctic stations like Barrow, Alert, Station Nord in Greenland and Zeppelin show a very pronounced winter/spring maximum in BC. While monthly averaged measured EBC values are around 80 ng/m3, the models severely underestimate this with some models simulating only a small percentage of the observed values. During summer measured concentrations are a magnitude lower, and still underestimated by almost an order of magnitude in some models. However, the best models are with a factor of 2 in winter/spring and realistic concentrations in summer. In order to get information on the vertical profile we used measurements from aircraft campaigns like ARCTAS, ARCPAC and HIPPO. It is found that BC in latitudes below 60 degrees is better captured by the models than BC at higher latitudes, even though it is overestimated at high altitudes. A systematic analysis of the performance of different models is presented. With the dataset we capture remote, polluted and fire-influenced conditions.
50% REDUCTION IN GLOBAL GHG EMISSION BY 2050 AND ITS IMPLICATION
NASA Astrophysics Data System (ADS)
Fujimori, Shinichiro; Masui, Toshihiko; Matsuoka, Yuzuru
To prevent the global temperature increase by two degrees, global greenhouse gas emission in 2050 should be cut by half relative to its 1990 level. This study shows following three things by using multi regions and sectors recursive dynamic type computable general equilibrium model. One is the feasibility of that global emission target. The others are the counter measures and the impact on the macro economy, if that target were feasible. In addition, the scenarios with and without international emission trading are implemented and the effect of the trading is analyzed. As a result, that target can be achieved. The marginal abatement cost is 750/tCO2-eq in 2050. Energy efficiency improvement, renewable energy and carbon capture and storage technologies are the main players as counter measures. If the emission trading is available freely, GDP loss is 4.5% globally in 2050. Otherwise, the loss is increased to 6.1%. The emission trading mechanism is also one of the important measures.
40 CFR 63.4361 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
... determine the mass fraction of TVH liquid input from each regulated material used in the web coating.../printing or dyeing/finishing operation during the capture efficiency test run, kg. TVHi = Mass fraction of... enclosure or building enclosure. The liquid-to-uncaptured-gas protocol compares the mass of liquid TVH in...
The Role of Natural Gas Power Plants with Carbon Capture and Storage in a Low-Carbon Future
Natural gas combined-cycle (NGCC) turbines with carbon capture and storage (CCS) are a promising technology for reducing carbon dioxide (CO2) emissions in the electric sector. However, the high cost and efficiency penalties associated with CCS, as well as methane leakage from nat...
40 CFR 63.4981 - What definitions apply to this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... subpart are defined in the CAA, in 40 CFR 63.2, and in this section as follows: Add-on control means an air pollution control device such as a thermal oxidizer or carbon adsorber that reduces pollution in... those emissions into an add-on air pollution control device. Capture efficiency or capture system...
40 CFR 63.4981 - What definitions apply to this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... subpart are defined in the CAA, in 40 CFR 63.2, and in this section as follows: Add-on control means an air pollution control device such as a thermal oxidizer or carbon adsorber that reduces pollution in... those emissions into an add-on air pollution control device. Capture efficiency or capture system...
40 CFR 63.4981 - What definitions apply to this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... subpart are defined in the CAA, in 40 CFR 63.2, and in this section as follows: Add-on control means an air pollution control device such as a thermal oxidizer or carbon adsorber that reduces pollution in... those emissions into an add-on air pollution control device. Capture efficiency or capture system...
40 CFR 63.4964 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
... operation are applied within the capture system; coating solvent flash-off and coating, curing, and drying... parts enter the open shop environment when being moved between a spray booth and a curing oven. (b... from the beginning to the end of production, which includes surface preparation activities and drying...
Among various clean energy technologies, one innovative option for reducing greenhouse gas (GHG) emissions involves pairing carbon capture and storage (CCS) with the production of synthetic fuels and electricity from co-processed coal and biomass. With a relatively pure CO2 strea...
40 CFR 63.4763 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2012 CFR
2012-07-01
...) and 63.7(e)(1), deviations that occur during a period of SSM of the emission capture system, add-on... identify as an SSM are violations, according to the provisions in § 63.6(e). (i) [Reserved] (j) You must...
40 CFR 63.4763 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2014 CFR
2014-07-01
...) and 63.7(e)(1), deviations that occur during a period of SSM of the emission capture system, add-on... identify as an SSM are violations, according to the provisions in § 63.6(e). (i) [Reserved] (j) You must...
40 CFR 63.4763 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2011 CFR
2011-07-01
...) and 63.7(e)(1), deviations that occur during a period of SSM of the emission capture system, add-on... identify as an SSM are violations, according to the provisions in § 63.6(e). (i) [Reserved] (j) You must...
40 CFR 63.4763 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2013 CFR
2013-07-01
...) and 63.7(e)(1), deviations that occur during a period of SSM of the emission capture system, add-on... identify as an SSM are violations, according to the provisions in § 63.6(e). (i) [Reserved] (j) You must...
40 CFR 63.4763 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2010 CFR
2010-07-01
...) and 63.7(e)(1), deviations that occur during a period of SSM of the emission capture system, add-on... identify as an SSM are violations, according to the provisions in § 63.6(e). (i) [Reserved] (j) You must...
EVALUATION OF THE EFFECT OF SCR ON MERCURY SPECIATION AND EMISSIONS
The paper presents the results of an investigation on the impact that selective catalytic reduction (SCR) has on both the total emissions and the speciation of mercury (Hg). SCR systems can be used as multipollutant technologies if they enhance Hg conversion/capture. Previous pil...
40 CFR 63.843 - Emission limits for existing sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
...) The emission capture system shall be installed and operated to meet the generally accepted engineering standards for minimum exhaust rates as published by the American Conference of Governmental Industrial Hygienists in Chapters 3 and 5 of “Industrial Ventilation: A Handbook of Recommended Practice” (incorporated...
40 CFR 63.843 - Emission limits for existing sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) The emission capture system shall be installed and operated to meet the generally accepted engineering standards for minimum exhaust rates as published by the American Conference of Governmental Industrial Hygienists in Chapters 3 and 5 of “Industrial Ventilation: A Handbook of Recommended Practice” (incorporated...
40 CFR 63.843 - Emission limits for existing sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) The emission capture system shall be installed and operated to meet the generally accepted engineering standards for minimum exhaust rates as published by the American Conference of Governmental Industrial Hygienists in Chapters 3 and 5 of “Industrial Ventilation: A Handbook of Recommended Practice” (incorporated...
40 CFR 63.843 - Emission limits for existing sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
...) The emission capture system shall be installed and operated to meet the generally accepted engineering standards for minimum exhaust rates as published by the American Conference of Governmental Industrial Hygienists in Chapters 3 and 5 of “Industrial Ventilation: A Handbook of Recommended Practice” (incorporated...
40 CFR 63.843 - Emission limits for existing sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) The emission capture system shall be installed and operated to meet the generally accepted engineering standards for minimum exhaust rates as published by the American Conference of Governmental Industrial Hygienists in Chapters 3 and 5 of “Industrial Ventilation: A Handbook of Recommended Practice” (incorporated...
This EPA-led project, conducted in collaboration with UNEP, the Swedish Environmental Institute and various Russian Institutes, that demonstrates that the mercury emission control efficiencies of activated carbon injection technologies applied at a Russian power plant burning Rus...
HIGHLIGHTS FROM TECHNICAL MANUAL ON HOOD SYSTEM CAPTURE OF PROCESS FUGITIVE PARTICULATE EMISSIONS
The paper discusses a technical manual whose emphasis is on the design and evaluation of actual hood systems used to control various fugitive particulate emission sources. Engineering analyses of the most important hood types are presented to provide a conceptual understanding of...
Glaser, Adam K; Zhang, Rongxiao; Gladstone, David J; Pogue, Brian W
2014-07-21
Recent studies have proposed that light emitted by the Cherenkov effect may be used for a number of radiation therapy dosimetry applications. There is a correlation between the captured light and expected dose under certain conditions, yet discrepancies have also been observed and a complete examination of the theoretical differences has not been done. In this study, a fundamental comparison between the Cherenkov emission and absorbed dose was explored for x-ray photons, electrons, and protons using both a theoretical and Monte Carlo-based analysis. Based on the findings of where dose correlates with Cherenkov emission, it was concluded that for x-ray photons the light emission would be optimally suited for narrow beam stereotactic radiation therapy and surgery validation studies, for verification of dynamic intensity-modulated and volumetric modulated arc therapy treatment plans in water tanks, near monoenergetic sources (e.g., Co-60 and brachy therapy sources) and also for entrance and exit surface imaging dosimetry of both narrow and broad beams. For electron use, Cherenkov emission was found to be only suitable for surface dosimetry applications. Finally, for proton dosimetry, there exists a fundamental lack of Cherenkov emission at the Bragg peak, making the technique of little use, although post-irradiation detection of light emission from radioisotopes could prove to be useful.
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.
The paper presents estimates of performance levels and related costs associated with controlling mercury (Hg) emissions from coal-fired power plants using either powdered activated carbon (PAC) injection or multipollutant control in which Hg capture is enhanced in existing and ne...
40 CFR 63.7143 - What definitions apply to this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Lime Manufacturing Plants Other... capture and transport PM to a control device. Control device means the air pollution control equipment used to reduce PM emissions released to the atmosphere from one or more process operations at an LMP...
40 CFR 63.7143 - What definitions apply to this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Lime Manufacturing Plants Other... capture and transport PM to a control device. Control device means the air pollution control equipment used to reduce PM emissions released to the atmosphere from one or more process operations at an LMP...
40 CFR 63.7143 - What definitions apply to this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Lime Manufacturing Plants Other... capture and transport PM to a control device. Control device means the air pollution control equipment used to reduce PM emissions released to the atmosphere from one or more process operations at an LMP...
40 CFR 63.7143 - What definitions apply to this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Lime Manufacturing Plants Other... capture and transport PM to a control device. Control device means the air pollution control equipment used to reduce PM emissions released to the atmosphere from one or more process operations at an LMP...
40 CFR 63.7143 - What definitions apply to this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Lime Manufacturing Plants Other... capture and transport PM to a control device. Control device means the air pollution control equipment used to reduce PM emissions released to the atmosphere from one or more process operations at an LMP...
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.
NASA Astrophysics Data System (ADS)
Bassett, Will P.; Dlott, Dana D.
2016-10-01
An emission spectrometer (450-850 nm) using a high-throughput, high numerical aperture (N.A. = 0.3) prism spectrograph with stepped fiberoptic coupling, 32 fast photomultipliers and thirty-two 1.25 GHz digitizers is described. The spectrometer can capture single-shot events with a high dynamic range in amplitude and time (nanoseconds to milliseconds or longer). Methods to calibrate the spectrometer and verify its performance and accuracy are described. When a reference thermal source is used for calibration, the spectrometer can function as a fast optical pyrometer. Applications of the spectrometer are illustrated by using it to capture single-shot emission transients from energetic materials or reactive materials initiated by kmṡs-1 impacts with laser-driven flyer plates. A log (time) data analysis method is used to visualize multiple kinetic processes resulting from impact initiation of HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) or a Zr/CuO nanolaminate thermite. Using a gray body algorithm to interpret the spectral radiance from shocked HMX, a time history of temperature and emissivity was obtained, which could be used to investigate HMX hot spot dynamics. Finally, two examples are presented showing how the spectrometer can avoid temperature determination errors in systems where thermal emission is accompanied by atomic or molecular emission lines.
Bassett, Will P; Dlott, Dana D
2016-10-01
An emission spectrometer (450-850 nm) using a high-throughput, high numerical aperture (N.A. = 0.3) prism spectrograph with stepped fiberoptic coupling, 32 fast photomultipliers and thirty-two 1.25 GHz digitizers is described. The spectrometer can capture single-shot events with a high dynamic range in amplitude and time (nanoseconds to milliseconds or longer). Methods to calibrate the spectrometer and verify its performance and accuracy are described. When a reference thermal source is used for calibration, the spectrometer can function as a fast optical pyrometer. Applications of the spectrometer are illustrated by using it to capture single-shot emission transients from energetic materials or reactive materials initiated by km⋅s -1 impacts with laser-driven flyer plates. A log (time) data analysis method is used to visualize multiple kinetic processes resulting from impact initiation of HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) or a Zr/CuO nanolaminate thermite. Using a gray body algorithm to interpret the spectral radiance from shocked HMX, a time history of temperature and emissivity was obtained, which could be used to investigate HMX hot spot dynamics. Finally, two examples are presented showing how the spectrometer can avoid temperature determination errors in systems where thermal emission is accompanied by atomic or molecular emission lines.
NASA Astrophysics Data System (ADS)
Kammann, Claudia; Schmidt, Hans-Peter; Williams, Anne; Hagemann, Nikolas; Marhan, Sven; Clough, Tim; Mueller, Christoph
2017-04-01
Pyrogenic carbon (biochar) produced from biomass may be used as a soil amendment to sequester biomass-C and to mitigate climate change. Moreover, biochar may increase soil fertility and optimize nutrient cycling in agro-ecosystems. However, according to meta-studies large additions (>10 t ha-1) of pure biochar, may only lead to moderate yield increases. Thus, there are no economic benefits for farmers to use biochar. Recently, it has been suggested that biochar may be used as an on-farm nutrient management tool (feed additive, liquid manure treatment, composting) to deliver small doses of nutrients and biochar to the soil each year. It may also be used as a carrier for (organic) nutrients in small doses (0.5 - 2 t ha-1) in the root zone; recent studies reported considerably increased yields. The mechanisms, however, are not well understood. Co-composted biochar was recently shown to promote plant growth due to its nutrient delivery and release capabilities, particularly nitrate (NO3-). To gain further insights into biochar-nitrogen (N) interactions, we conducted a 15N labelling-tracing study under controlled conditions with treatments consisting of a non-biochar amended control, 2% (wt/wt) of untreated biochar particles (BCpure ,no intrinsic content of nitrate) and a 2% co-composted biochar (BCcomp, 5.3 g NO3-N kg-1 as a result of composting), replicated thrice. Biochars were added to a sandy loam soil in jars (200 g) planted with barley (Hordeum vulgare L.) seedlings. Fertilizer (NH4NO3) was homogenously added with either the ammonium (NH4+) or the nitrate (NO3-) pools 15N labelled (60 atom% 15N) hours before planting the seedlings. Sets of 18 jars were harvested on days 1, 3, 8, 15 and 29 and nitrogen pools were analysed to trace 15N fertilizer fate (soil mineral N, plant biomass, biochar particles, nitrous oxide (N2O) emissions). Interestingly, both BCpure and BCcomp captured fertilizer 15N from the soil matrix within hours of addition, with higher capture of 15N-NO3 than 15N-NH4. Surprisingly, the already nitrate-enriched BCcomp captured significantly more 15N than the non-enriched BCpure. Plant biomass increased significantly in the BCcomp compared to both BCpure and control treatment, because BCcomp still delivered N to the growing plants when soil mineral N was already depleted. N2O emissions were lower in the BCcomp treatment (by 60%) and the BCpure treatment (by 67%) compared to the control, despite higher levels of mineral N introduced with BCcomp. The 15N-N2O enrichment suggested that with biochar a relatively larger proportion was contributed by nitrification (although denitrification still dominated); and that accelerated mineralization-nitrification from unlabelled soil organic N pools diluted the 15N-nitrate label. Our results suggest that nitrate capture in biochar particles may be one of the mechanism among others reducing N2O emissions. In conclusion, modifying and designing biochars by organic pre-treatments may promote plant growth while N2O emission reduction is still possible. However more research is needed to achieve the envisaged economic and environmental benefits of C-sequestering biochar use in agriculture. Acknowledgement: CK gratefully acknowledges the financial support of DFG grant no. Ka3442/1-1.
Kirchofer, Abby; Becker, Austin; Brandt, Adam; Wilcox, Jennifer
2013-07-02
The availability of industrial alkalinity sources is investigated to determine their potential for the simultaneous capture and sequestration of CO2 from point-source emissions in the United States. Industrial alkalinity sources investigated include fly ash, cement kiln dust, and iron and steel slag. Their feasibility for mineral carbonation is determined by their relative abundance for CO2 reactivity and their proximity to point-source CO2 emissions. In addition, the available aggregate markets are investigated as possible sinks for mineral carbonation products. We show that in the U.S., industrial alkaline byproducts have the potential to mitigate approximately 7.6 Mt CO2/yr, of which 7.0 Mt CO2/yr are CO2 captured through mineral carbonation and 0.6 Mt CO2/yr are CO2 emissions avoided through reuse as synthetic aggregate (replacing sand and gravel). The emission reductions represent a small share (i.e., 0.1%) of total U.S. CO2 emissions; however, industrial byproducts may represent comparatively low-cost methods for the advancement of mineral carbonation technologies, which may be extended to more abundant yet expensive natural alkalinity sources.
Characterization of boron coated vitreous carbon foam for neutron detection
NASA Astrophysics Data System (ADS)
Lavelle, C. M.; Deacon, Ryan M.; Hussey, Daniel S.; Coplan, Michael; Clark, Charles W.
2013-11-01
Reticulated vitreous carbon (RVC) foams coated with 3-11 μm thick layers of boron carbide (B4C) are experimentally characterized for use as an active material for neutron detection. The potential advantage of this material over thin films is that it can be fabricated in any shape and its porous structure may enhance the emission surface area for ionizing charged particles following thermal neutron capture. A coated foam is also advantageous because the neutron-absorbing material is only on the surface, which is more efficient for α particle emission on a per captured neutron basis. Measurements of the B4C layer thickness of an RVC coated foam, and determination of its elemental composition, are performed using scanning electron microscopy. Neutron transmission measurements using neutron radiography are presented and α particle emission from the coated foam in response to a moderated 252Cf thermal neutron source is demonstrated.
40 CFR 63.4964 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2014 CFR
2014-07-01
... to 40 CFR part 51 to determine the mass fraction, kg TVH per kg material, of TVH liquid input from... the coating operation during the capture efficiency test run, lb. TVHi = Mass fraction of TVH in... temporary total enclosure or building enclosure. The liquid-to-uncaptured-gas protocol compares the mass of...
40 CFR 63.3544 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2014 CFR
2014-07-01
... mass fraction of TVH liquid input from each coating and thinner used in the coating operation during... materials used in the coating operation during the capture efficiency test run, kg. TVHi = Mass fraction of... protocol compares the mass of liquid TVH in materials used in the coating operation to the mass of TVH...
40 CFR 63.4964 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2013 CFR
2013-07-01
... to 40 CFR part 51 to determine the mass fraction, kg TVH per kg material, of TVH liquid input from... the coating operation during the capture efficiency test run, lb. TVHi = Mass fraction of TVH in... temporary total enclosure or building enclosure. The liquid-to-uncaptured-gas protocol compares the mass of...
40 CFR 63.4165 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2013 CFR
2013-07-01
... to 40 CFR part 51 to determine the mass fraction of TVH liquid input from each coating, thinner, and... operation during the capture efficiency test run, kg. TVHi = mass fraction of TVH in coating, thinner, or... temporary total enclosure or building enclosure. The liquid-to-uncaptured-gas protocol compares the mass of...
40 CFR 63.4964 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
... determine the mass fraction, kg TVH per kg material, of TVH liquid input from each coating, thinner, and... capture efficiency test run, lb. TVHi = Mass fraction of TVH in coating, thinner, or cleaning material, i... enclosure. The liquid-to-uncaptured-gas protocol compares the mass of liquid TVH in materials used in the...
40 CFR 63.3544 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2012 CFR
2012-07-01
... mass fraction of TVH liquid input from each coating and thinner used in the coating operation during... materials used in the coating operation during the capture efficiency test run, kg. TVHi = Mass fraction of... protocol compares the mass of liquid TVH in materials used in the coating operation to the mass of TVH...
40 CFR 63.4165 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2011 CFR
2011-07-01
... to 40 CFR part 51 to determine the mass fraction of TVH liquid input from each coating, thinner, and... operation during the capture efficiency test run, kg. TVHi = mass fraction of TVH in coating, thinner, or... temporary total enclosure or building enclosure. The liquid-to-uncaptured-gas protocol compares the mass of...
40 CFR 63.3544 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2013 CFR
2013-07-01
... mass fraction of TVH liquid input from each coating and thinner used in the coating operation during... materials used in the coating operation during the capture efficiency test run, kg. TVHi = Mass fraction of... protocol compares the mass of liquid TVH in materials used in the coating operation to the mass of TVH...
40 CFR 63.4964 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2012 CFR
2012-07-01
... to 40 CFR part 51 to determine the mass fraction, kg TVH per kg material, of TVH liquid input from... the coating operation during the capture efficiency test run, lb. TVHi = Mass fraction of TVH in... temporary total enclosure or building enclosure. The liquid-to-uncaptured-gas protocol compares the mass of...
Natural gas combined-cycle (NGCC) turbines with carbon capture and storage (CCS) are a promising technology for reducing carbon dioxide (CO2) emissions in the electric sector. However, the high cost and efficiency penalties associated with CCS, as well as methane leakage from nat...
40 CFR 63.3544 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
... system, and coating solvent flash-off, curing, and drying occurs within the capture system. For example, the criterion is not met if parts enter the open shop environment when being moved between a spray... time required for a single part to go from the beginning to the end of production, and includes drying...
40 CFR 63.4565 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
... solvent flash-off, curing, and drying occurs within the capture system; and the removal or evaporation of..., this criterion is not met if parts enter the open shop environment when being moved between a spray... surface preparation activities and drying and curing time. (c) Liquid-to-uncaptured-gas protocol using a...
40 CFR 63.4765 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2010 CFR
2010-07-01
... coating, curing, and drying occurs within the capture system; and the removal or evaporation of cleaning... criterion is not met if parts enter the open shop environment when being moved between a spray booth and a... activities and drying or curing time. (c) Liquid-to-uncaptured-gas protocol using a temporary total enclosure...
Code of Federal Regulations, 2014 CFR
2014-07-01
... capture system and add-on control device operating limits during the performance test? 63.3556 Section 63... system and add-on control device operating limits during the performance test? During the performance... of key parameters of the valve operating system (e.g., solenoid valve operation, air pressure...
Code of Federal Regulations, 2012 CFR
2012-07-01
... capture system and add-on control device operating limits during the performance test? 63.3556 Section 63... system and add-on control device operating limits during the performance test? During the performance... of key parameters of the valve operating system (e.g., solenoid valve operation, air pressure...
Code of Federal Regulations, 2013 CFR
2013-07-01
... converter department uses Pierce-Smith converters, the capture system design must include use of a primary... discharged to the atmosphere from any Pierce-Smith converter primary hood capture system or Hoboken converter... construction commenced on or after April 20, 1998, the use of batch copper converters is prohibited. (f...
Code of Federal Regulations, 2012 CFR
2012-07-01
... converter department uses Pierce-Smith converters, the capture system design must include use of a primary... discharged to the atmosphere from any Pierce-Smith converter primary hood capture system or Hoboken converter... construction commenced on or after April 20, 1998, the use of batch copper converters is prohibited. (f...
Code of Federal Regulations, 2014 CFR
2014-07-01
... converter department uses Pierce-Smith converters, the capture system design must include use of a primary... discharged to the atmosphere from any Pierce-Smith converter primary hood capture system or Hoboken converter... construction commenced on or after April 20, 1998, the use of batch copper converters is prohibited. (f...
High-resolution infrared thermography for capturing wildland fire behaviour - RxCADRE 2012
Joseph J. O’Brien; E. Louise Loudermilk; Benjamin Hornsby; Andrew T. Hudak; Benjamin C. Bright; Matthew B. Dickinson; J. Kevin Hiers; Casey Teske; Roger D. Ottmar
2016-01-01
Wildland fire radiant energy emission is one of the only measurements of combustion that can be made at wide spatial extents and high temporal and spatial resolutions. Furthermore, spatially and temporally explicit measurements are critical for making inferences about fire effects and useful for examining patterns of fire spread. In this study we describe our...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kabalka, G. W.
2005-06-28
The primary objective of the project was the development of in vivo methods for the detection and evaluation of tumors in humans. The project was focused on utilizing positron emission tomography (PET) to monitor the distribution and pharamacokinetics of a current boron neutron capture therapy (BNCT) agent, p-boronophenylalanine (BPA) by labeling it with a fluorine-18, a positron emitting isotope. The PET data was then used to develop enhanced treatment planning protocols. The study also involved the synthesis of new tumor selective BNCTagents that could be labeled with radioactive nuclides for the in vivo detection of boron.
Field emission chemical sensor
Panitz, J.A.
1983-11-22
A field emission chemical sensor for specific detection of a chemical entity in a sample includes a closed chamber enclosing two field emission electrode sets, each field emission electrode set comprising (a) an electron emitter electrode from which field emission electrons can be emitted when an effective voltage is connected to the electrode set; and (b) a collector electrode which will capture said electrons emitted from said emitter electrode. One of the electrode sets is passive to the chemical entity and the other is active thereto and has an active emitter electrode which will bind the chemical entity when contacted therewith.
The Chemical Route to a Carbon Dioxide Neutral World.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lamarque, J. F.; Bond, Tami C.; Eyring, Veronika
2010-08-11
We present and discuss a new dataset of gridded emissions covering the historical period (1850-2000) in decadal increments at a horizontal resolution of 0.5° in latitude and longitude. The primary purpose of this inventory is to provide consistent gridded emissions of reactive gases and aerosols for use in chemistry model simulations needed by climate models for the Climate Model Intercomparison Program #5 (CMIP5) in support of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment report. Our best estimate for the year 2000 inventory represents a combination of existing regional and global inventories to capture the best information available atmore » this point; 40 regions and 12 sectors were used to combine the various sources. The historical reconstruction of each emitted compound, for each region and sector, was then forced to agree with our 2000 estimate, ensuring continuity between past and 2000 emissions. Application of these emissions into two chemistry-climate models is used to test their ability to capture long-term changes in atmospheric ozone, carbon monoxide and aerosols distributions. The simulated long-term change in the Northern mid-latitudes surface and mid-troposphere ozone is not quite as rapid as observed. However, stations outside this latitude band show much better agreement in both present-day and long-term trend. The model simulations consistently underestimate the carbon monoxide trend, while capturing the long-term trend at the Mace Head station. The simulated sulfate and black carbon deposition over Greenland is in very good agreement with the ice-core observations spanning the simulation period. Finally, aerosol optical depth and additional aerosol diagnostics are shown to be in good agreement with previously published estimates.« less
Deep Optical Spectroscopy of Planetary Nebulae: The Search for Neutron-Capture Elements
NASA Astrophysics Data System (ADS)
Sterling, Nicholas C.; Garofali, K.; Dinerstein, H. L.; Hwang, S.; Redfield, S.
2013-01-01
We present deep, high-resolution (R=36,700) optical spectra of five planetary nebulae (PNe), taken with the 2D-coude echelle spectrograph on the 2.7-m Harlan J. Smith Telescope at McDonald Observatory. These observations are part of a larger optical survey of PNe, designed to unambiguously detect emission lines from neutron(n)-capture elements (atomic number Z>30). The abundances of these elements are of particular interest in PNe, since they can be produced by slow n-capture nucleosynthesis (the ``s-process'') during the asymptotic giant branch (AGB) stage of evolution of PN progenitor stars. The first large-scale investigation of n-capture element abundances in PNe (Sterling & Dinerstein 2008, ApJS, 174, 157) surveyed [Kr III] and [Se IV] transitions in the K band spectra of more than 80 PNe. However, the abundances derived from these data relied on ionization corrections that were often large and uncertain due to the detection of only one ion per element. Transitions of other Se and Kr ions, as well as many other trans-iron species, reside at optical wavelengths. High-resolution spectra are essential to unequivocally identify these lines and resolve potential blends with other species. The spectra we present are rich in emission features, with between 125 and 600 distinct lines detected in each PN. Emission from at least one Kr ion is detected in all five objects, and two (Hb 12 and J 900) exhibit emission from multiple Kr ions. We detected multiple Xe ions in J 900, as well as Se, Br, and Rb lines. Hb 12 also exhibits Xe emission, and the first detection of [Se II] in a PN to our knowledge. The spectra display a wealth of other emission lines, including permitted features of second-row elements and forbidden transitions of several iron-peak elements (e.g., Cr, Mn, Fe, Co, Ni, and Cu). Our survey makes it possible to derive more accurate Se and Kr abundances in PNe, and reveals the enrichment of other trans-iron elements. This enables more accurate s-process enrichment factors to be derived for PNe, providing important constraints to models of AGB nucleosynthesis and the chemical evolution of trans-iron nuclides. This research was supported by NSF awards AST-0708425 and AST-901432.
40 CFR 63.3542 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2010 CFR
2010-07-01
... limit in § 63.3490. Alternatively, if you calculate an OSEL for all coating type segments within a... of startup, shutdown, or malfunction of the emission capture system, add-on control device, or... Administrator will determine whether deviations that occur during a period you identify as a startup, shutdown...
40 CFR 63.3542 - How do I demonstrate continuous compliance with the emission limitations?
Code of Federal Regulations, 2011 CFR
2011-07-01
... limit in § 63.3490. Alternatively, if you calculate an OSEL for all coating type segments within a... of startup, shutdown, or malfunction of the emission capture system, add-on control device, or... Administrator will determine whether deviations that occur during a period you identify as a startup, shutdown...
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.
Tomography of a simply magnetized toroidal plasma
NASA Astrophysics Data System (ADS)
Ruggero, BARNI; Stefano, CALDIROLA; Luca, FATTORINI; Claudia, RICCARDI
2018-02-01
Optical emission spectroscopy is a passive diagnostic technique, which does not perturb the plasma state. In particular, in a hydrogen plasma, Balmer-alpha (H α ) emission can be easily measured in the visible range along a line of sight from outside the plasma vessel. Other emission lines in the visible spectral range from hydrogen atoms and molecules can be exploited too, in order to gather complementary pieces of information on the plasma state. Tomography allows us to capture bi-dimensional structures. We propose to adopt an emission spectroscopy tomography for studying the transverse profiles of magnetized plasmas when Abel inversion is not exploitable. An experimental campaign was carried out at the Thorello device, a simple magnetized torus. The characteristics of the profile extraction method, which we implemented for this purpose are discussed, together with a few results concerning the plasma profiles in a simply magnetized torus configuration.
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
NASA Astrophysics Data System (ADS)
Spokas, K.; Patrizio, P.; Leduc, S.; Mesfun, S.; Kraxner, F.
2017-12-01
Reducing electricity-sector emissions relies heavily on countries' abilities to either transition away from carbon-intensive energy generation or to sequester its resultant emissions with carbon capture and storage (CCS) technologies. The use of biomass energy technologies in conjunction with carbon capture and sequestration (BECCS) presents the opportunity for net reductions in atmospheric carbon dioxide. In this study, we investigate the limitations of several common policy mechanisms to incentivize the deployment of BECCS using the techno-economic spatial optimization model BeWhere (www.iiasa.ac.at/bewhere). We consider a set of coal and natural gas power plants in the United States (U.S.) selected using a screening process that considers capacity, boiler age, and capacity factor for electricity-generation units from the EPA 2014 eGRID database. The set makes up 470 GW of generation, and produces 8,400 PJ and 2.07 GtCO2 annually. Co-firing up to 15% for coal power plants is considered, using woody-biomass residues sourced from certified and managed U.S. forests obtained from the G4M (www.iiasa.ac.at/g4m) and GeoWiki (www.geo-wiki.org) database. Geologic storage is considered with injectivity and geomechanical limitations to ensure safe storage. Costs are minimized under two policy mechanisms: a carbon tax and geologic carbon sequestration credits, such as the Q45 credits. Results show that the carbon tax scenario incentivizes co-firing at low to medium carbon taxes, but is replaced by CCS at higher tax values. Carbon taxes do not strongly incentivize BECCS, as negative emissions associated with sequestering carbon content are not accounted as revenue. On the other hand, carbon credit scenarios result in significant CCS deployment, but lack any incentive for co-firing.
NASA Astrophysics Data System (ADS)
Wang, Haibin; Zhou, Peilin; Wang, Zhongcheng
2017-06-01
Concern about global climate change is growing, and many projects and researchers are committed to reducing greenhouse gases from all possible sources. International Maritime (IMO) has set a target of 20% CO2 reduction from shipping by 2020 and also presented a series of carbon emission reduction methods, which are known as Energy Efficiency Design Index (EEDI) and Energy Efficiency Operation Indicator (EEOI). Reviews on carbon emission reduction from all industries indicate that, Carbon Capture and Storage (CCS) is an excellent solution to global warming. In this paper, a comprehensive literature review of EEDI and EEOI and CCS is conducted and involves reviewing current policies, introducing common technologies, and considering their feasibilities for marine activities, mainly shipping. Current projects are also presented in this paper, thereby illustrating that carbon emission reduction has been the subject of attention from all over the world. Two case ship studies indicate the economic feasibility of carbon emission reduction and provide a guide for CCS system application and practical installation on ships.
Exploratory investigations of hypervelocity intact capture spectroscopy
NASA Technical Reports Server (NTRS)
Tsou, P.; Griffiths, D. J.
1993-01-01
The ability to capture hypervelocity projectiles intact opens a new technique available for hypervelocity research. A determination of the reactions taking place between the projectile and the capture medium during the process of intact capture is extremely important to an understanding of the intact capture phenomenon, to improving the capture technique, and to developing a theory describing the phenomenon. The intact capture of hypervelocity projectiles by underdense media generates spectra, characteristic of the material species of projectile and capture medium involved. Initial exploratory results into real-time characterization of hypervelocity intact capture techniques by spectroscopy include ultra-violet and visible spectra obtained by use of reflecting gratings, transmitting gratings, and prisms, and recorded by photographic and electronic means. Spectrometry proved to be a valuable real-time diagnostic tool for hypervelocity intact capture events, offering understanding of the interactions of the projectile and the capture medium during the initial period and providing information not obtainable by other characterizations. Preliminary results and analyses of spectra produced by the intact capture of hypervelocity aluminum spheres in polyethylene (PE), polystyrene (PS), and polyurethane (PU) foams are presented. Included are tentative emission species identifications, as well as gray body temperatures produced in the intact capture process.
USDA-ARS?s Scientific Manuscript database
Due to concerns surrounding its ozone depletion potential, there is a need for technologies to capture and destroy methyl bromide (CH3Br) emissions from post-harvest fumigations applied to control agricultural pests. Previously we described a system in which CH3Br fumes vented from fumigation chambe...
40 CFR 63.4361 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Method 204A or 204F of appendix M to 40 CFR part 51 to determine the mass fraction of TVH liquid input... the capture efficiency test run, kg. TVHi = Mass fraction of TVH in regulated material, i, that is... protocol compares the mass of liquid TVH in regulated materials applied in the web coating/printing or...
40 CFR 63.4361 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2012 CFR
2012-07-01
... Method 204A or 204F of appendix M to 40 CFR part 51 to determine the mass fraction of TVH liquid input... the capture efficiency test run, kg. TVHi = Mass fraction of TVH in regulated material, i, that is... protocol compares the mass of liquid TVH in regulated materials applied in the web coating/printing or...
Code of Federal Regulations, 2010 CFR
2010-07-01
... system and add-on control device operating limits during the performance test? 63.3967 Section 63.3967... capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.3892 according to this section, unless you have received...
Code of Federal Regulations, 2011 CFR
2011-07-01
... system and add-on control device operating limits during the performance test? 63.3967 Section 63.3967... capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.3892 according to this section, unless you have received...
Code of Federal Regulations, 2013 CFR
2013-07-01
... system and add-on control device operating limits during the performance test? 63.4567 Section 63.4567... capture system and add-on control device operating limits during the performance test? During the... the operating limits required by § 63.4492 according to this section, unless you have received...
Trends and Patterns in a New Time Series of Natural and Anthropogenic Methane Emissions, 1980-2000
NASA Astrophysics Data System (ADS)
Matthews, E.; Bruhwiler, L.; Themelis, N. J.
2007-12-01
We report on a new time series of methane (CH4) emissions from anthropogenic and natural sources developed for a multi-decadal methane modeling study (see following presentation by Bruhwiler et al.). The emission series extends from 1980 through the early 2000s with annual emissions for all countries has several features distinct from the source histories based on IPCC methods typically employed in modeling the global methane cycle. Fossil fuel emissions rely on 7 fuel-process emission combinations and minimize reliance on highly-uncertain emission factors. Emissions from ruminant animals employ regional profiles of bovine populations that account for the influence of variable age- and size-demographics on emissions and are ~15% lower than other estimates. Waste-related emissions are developed using an approach that avoids using of data-poor emission factors and accounts for impacts of recycling and thermal treatment of waste on diverting material from landfills and CH4 capture at landfill facilities. Emissions from irrigated rice use rice-harvest areas under 3 water-management systems and a new historical data set that analyzes multiple sources for trends in water management since 1980. A time series of emissions from natural wetlands was developed by applying a multiple-regression model derived from full process-based model of Walter with analyzed meteorology from the ERA-40 reanalysis.
Developing Particle Emission Inventories Using Remote Sensing (PEIRS)
NASA Technical Reports Server (NTRS)
Tang, Chia-Hsi; Coull, Brent A.; Schwartz, Joel; Lyapustin, Alexei I.; Di, Qian; Koutrakis, Petros
2016-01-01
Information regarding the magnitude and distribution of PM(sub 2.5) emissions is crucial in establishing effective PM regulations and assessing the associated risk to human health and the ecosystem. At present, emission data is obtained from measured or estimated emission factors of various source types. Collecting such information for every known source is costly and time consuming. For this reason, emission inventories are reported periodically and unknown or smaller sources are often omitted or aggregated at large spatial scale. To address these limitations, we have developed and evaluated a novel method that uses remote sensing data to construct spatially-resolved emission inventories for PM(sub 2.5). This approach enables us to account for all sources within a fixed area, which renders source classification unnecessary. We applied this method to predict emissions in the northeast United States during the period of 2002-2013 using high- resolution 1 km x 1 km Aerosol Optical Depth (AOD). Emission estimates moderately agreed with the EPA National Emission Inventory (R(sup2) = 0.66 approx. 0.71, CV = 17.7 approx. 20%). Predicted emissions are found to correlate with land use parameters suggesting that our method can capture emissions from land use-related sources. In addition, we distinguished small-scale intra-urban variation in emissions reflecting distribution of metropolitan sources. In essence, this study demonstrates the great potential of remote sensing data to predict particle source emissions cost-effectively.
Developing Particle Emission Inventories Using Remote Sensing (PEIRS)
Tang, Chia-Hsi; Coull, Brent A.; Schwartz, Joel; Lyapustin, Alexei I.; Di, Qian; Koutrakis, Petros
2018-01-01
Information regarding the magnitude and distribution of PM2.5 emissions is crucial in establishing effective PM regulations and assessing the associated risk to human health and the ecosystem. At present, emission data is obtained from measured or estimated emission factors of various source types. Collecting such information for every known source is costly and time consuming. For this reason, emission inventories are reported periodically and unknown or smaller sources are often omitted or aggregated at large spatial scale. To address these limitations, we have developed and evaluated a novel method that uses remote sensing data to construct spatially-resolved emission inventories for PM2.5. This approach enables us to account for all sources within a fixed area, which renders source classification unnecessary. We applied this method to predict emissions in the northeast United States during the period of 2002–2013 using high- resolution 1 km × 1km Aerosol Optical Depth (AOD). Emission estimates moderately agreed with the EPA National Emission Inventory (R2=0.66~0.71, CV = 17.7~20%). Predicted emissions are found to correlate with land use parameters suggesting that our method can capture emissions from land use-related sources. In addition, we distinguished small-scale intra-urban variation in emissions reflecting distribution of metropolitan sources. In essence, this study demonstrates the great potential of remote sensing data to predict particle source emissions cost-effectively. PMID:27653469
Analysis of MCNP simulated gamma spectra of CdTe detectors for boron neutron capture therapy.
Winkler, Alexander; Koivunoro, Hanna; Savolainen, Sauli
2017-06-01
The next step in the boron neutron capture therapy (BNCT) is the real time imaging of the boron concentration in healthy and tumor tissue. Monte Carlo simulations are employed to predict the detector response required to realize single-photon emission computed tomography in BNCT, but have failed to correctly resemble measured data for cadmium telluride detectors. In this study we have tested the gamma production cross-section data tables of commonly used libraries in the Monte Carlo code MCNP in comparison to measurements. The cross section data table TENDL-2008-ACE is reproducing measured data best, whilst the commonly used ENDL92 and other studied libraries do not include correct tables for the gamma production from the cadmium neutron capture reaction that is occurring inside the detector. Furthermore, we have discussed the size of the annihilation peaks of spectra obtained by cadmium telluride and germanium detectors. Copyright © 2017 Elsevier Ltd. All rights reserved.
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.
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.
Field emission chemical sensor for receptor/binder, such as antigen/antibody
Panitz, John A.
1986-01-01
A field emission chemical sensor for specific detection of a chemical entity in a sample includes a closed chamber enclosing two field emission electrode sets, each field emission electrode set comprising (a) an electron emitter electrode from which field emission electrons can be emitted when an effective voltage is connected to the electrode set; and (b) a collector electrode which will capture said electrons emitted from said emitter electrode. One of the electrode sets is passive to the chemical entity and the other is active thereto and has an active emitter electrode which will bind the chemical entity when contacted therewith.
40 CFR 63.4900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... and add-on control device to comply with the emission limitations in § 63.4890, you must develop a... SSMP must address the startup, shutdown, and corrective actions in the event of a malfunction of the emission capture system or the add-on control device. The SSMP must also address any coating operation...
40 CFR 63.4900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... and add-on control device to comply with the emission limitations in § 63.4890, you must develop a... SSMP must address the startup, shutdown, and corrective actions in the event of a malfunction of the emission capture system or the add-on control device. The SSMP must also address any coating operation...
40 CFR 63.4900 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... and add-on control device to comply with the emission limitations in § 63.4890, you must develop a... SSMP must address the startup, shutdown, and corrective actions in the event of a malfunction of the emission capture system or the add-on control device. The SSMP must also address any coating operation...
Reducing cement's CO2 footprint
van Oss, Hendrik G.
2011-01-01
The manufacturing process for Portland cement causes high levels of greenhouse gas emissions. However, environmental impacts can be reduced by using more energy-efficient kilns and replacing fossil energy with alternative fuels. Although carbon capture and new cements with less CO2 emission are still in the experimental phase, all these innovations can help develop a cleaner cement industry.
Tuning the Photon Statistics of a Strongly Coupled Nanophotonic System
NASA Astrophysics Data System (ADS)
Dory, C.; Fischer, K. A.; Müller, K.; Lagoudakis, K. G.; Sarmiento, T.; Rundquist, A.; Zhang, J. L.; Kelaita, Y.; Sapra, N. V.; Vučković, J.
Strongly coupled quantum-dot-photonic-crystal cavity systems provide a nonlinear ladder of hybridized light-matter states, which are a promising platform for non-classical light generation. The transmission of light through such systems enables light generation with tunable photon counting statistics. By detuning the frequencies of quantum emitter and cavity, we can tune the transmission of light to strongly enhance either single- or two-photon emission processes. However, these nanophotonic systems show a strongly dissipative nature and classical light obscures any quantum character of the emission. In this work, we utilize a self-homodyne interference technique combined with frequency-filtering to overcome this obstacle. This allows us to generate emission with a strong two-photon component in the multi-photon regime, where we measure a second-order coherence value of g (2) [ 0 ] = 1 . 490 +/- 0 . 034 . We propose rate equation models that capture the dominant processes of emission both in the single- and multi-photon regimes and support them by quantum-optical simulations that fully capture the frequency filtering of emission from our solid-state system. Finally, we simulate a third-order coherence value of g (3) [ 0 ] = 0 . 872 +/- 0 . 021 . Army Research Office (ARO) (W911NF1310309), National Science Foundation (1503759), Stanford Graduate Fellowship.
The urgency of the development of CO2 capture from ambient air
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
Code of Federal Regulations, 2010 CFR
2010-07-01
... control device which is not taken into account when demonstrating compliance with the applicable emission limitations? You may have capture systems or add-on control devices which you choose not to take into account... system or add-on control device which is not taken into account when demonstrating compliance with the...
Multispectral laser-induced fluorescence imaging system for large biological samples
NASA Astrophysics Data System (ADS)
Kim, Moon S.; Lefcourt, Alan M.; Chen, Yud-Ren
2003-07-01
A laser-induced fluorescence imaging system developed to capture multispectral fluorescence emission images simultaneously from a relatively large target object is described. With an expanded, 355-nm Nd:YAG laser as the excitation source, the system captures fluorescence emission images in the blue, green, red, and far-red regions of the spectrum centered at 450, 550, 678, and 730 nm, respectively, from a 30-cm-diameter target area in ambient light. Images of apples and of pork meat artificially contaminated with diluted animal feces have demonstrated the versatility of fluorescence imaging techniques for potential applications in food safety inspection. Regions of contamination, including sites that were not readily visible to the human eye, could easily be identified from the images.
An innovative permanent total enclosure for blast cleaning and painting ships in drydock
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garland, C.; Lukey, M.
1997-12-31
This paper describes a new innovative Permanent Total Enclosure, or CAPE system, which encloses and captures emissions from blast cleaning and painting ship hulls in drydock. A description of the modular enclosure towers with unique seals is shown with several figures. The support barge with its environmental control equipment which includes a dust collector, VOC thermal oxidizer, dehumidifier, boiler, heating coils, air flow fans and, system controls is also described. Data measurements from the first two applications rate this system at 100 percent capture efficiency, 99 percent VOC destruction efficiency and 99.9 percent dust collection efficiency. Ships can be blastmore » cleaned and painted using noncompliant paints and meet all state and federal standards for air emissions.« less
NASA Astrophysics Data System (ADS)
Rani, Abha; Singh, Udayan; Jayant; Singh, Ajay K.; Sankar Mahapatra, Siba
2017-07-01
Coal gasification processes are crucial to decarbonisation in the power sector. While underground coal gasification (UCG) and integrated gasification combined cycle (IGCC) are different in terms of the site of gasification, they have considerable similarities in terms of the types of gasifiers used. Of course, UCG offers some additional advantages such as reduction of the fugitive methane emissions accompanying the coal mining process. Nevertheless, simulation of IGCC plants involving surface coal gasification is likely to give reasonable indication of the 3E (efficiency, economics and emissions) prospects of the gasification pathway towards electricity. This paper will aim at Estimating 3E impacts (efficiency, environment, economics) of gasification processes using simulation carried out in the Integrated Environmental Control Model (IECM) software framework. Key plant level controls which will be studied in this paper will be based on Indian financial regulations and operating costs which are specific to the country. Also, impacts of CO2 capture and storage (CCS) in these plants will be studied. The various parameters that can be studied are plant load factor, impact of coal quality and price, type of CO2 capture process, capital costs etc. It is hoped that relevant insights into electricity generation from gasification may be obtained with this paper.
Hydropower's Biogenic Carbon Footprint.
Scherer, Laura; Pfister, Stephan
2016-01-01
Global warming is accelerating and the world urgently needs a shift to clean and renewable energy. Hydropower is currently the largest renewable source of electricity, but its contribution to climate change mitigation is not yet fully understood. Hydroelectric reservoirs are a source of biogenic greenhouse gases and in individual cases can reach the same emission rates as thermal power plants. Little is known about the severity of their emissions at the global scale. Here we show that the carbon footprint of hydropower is far higher than previously assumed, with a global average of 173 kg CO2 and 2.95 kg CH4 emitted per MWh of electricity produced. This results in a combined average carbon footprint of 273 kg CO2e/MWh when using the global warming potential over a time horizon of 100 years (GWP100). Nonetheless, this is still below that of fossil energy sources without the use of carbon capture and sequestration technologies. We identified the dams most promising for capturing methane for use as alternative energy source. The spread among the ~1500 hydropower plants analysed in this study is large and highlights the importance of case-by-case examinations.
Comparing Solar-Flare Acceleration of >-20 MeV Protons and Electrons Above Various Energies
NASA Technical Reports Server (NTRS)
Shih, Albert Y.
2010-01-01
A large fraction (up to tens of percent) of the energy released in solar flares goes into accelerated ions and electrons, and studies indicate that these two populations have comparable energy content. RHESSI observations have shown a striking close linear correlation between the 2.223 MeV neutron-capture gamma-ray line and electron bremsstrahlung emission >300 keV, indicating that the flare acceleration of >^20 MeV protons and >300 keV electrons is roughly proportional over >3 orders of magnitude in fluence. We show that the correlations of neutron-capture line fluence with GOES class or with bremsstrahlung emission at lower energies show deviations from proportionality, primarily for flares with lower fluences. From analyzing thirteen flares, we demonstrate that there appear to be two classes of flares with high-energy acceleration: flares that exhibit only proportional acceleration of ions and electrons down to 50 keV and flares that have an additional soft, low-energy bremsstrahlung component, suggesting two separate populations of accelerated electrons. We use RHESSI spectroscopy and imaging to investigate a number of these flares in detail.
Adom, Philip Kofi; Kwakwa, Paul Adjei; Amankwaa, Afua
2018-07-15
This study examines the long-run drivers of potential and actual CO 2 emissions in Ghana, a sub-Saharan Africa country. The use of the former helps address the reverse causality problem and capture the true long-run effects. The Stock-Watson dynamic OLS is used with data from 1970 to 2014. The result shows that potential CO 2 emissions improve model efficiency. Income (except in "other sector") and financial development (except in manufacturing and construction sector) have compelling positive and negative effects on actual and potential CO 2 emissions, respectively. A higher price (oil and electricity) reduces actual and potential CO 2 emissions, but electricity price is more vital in residential, buildings and commercial and public services sector, while oil price is crucial in the transport sector. Democracy lowers actual and potential CO 2 emissions in the aggregate (insignificant) and transport sectors but raises it in the manufacturing and construction sector. The effect is, however, inconsistent for the remaining sectors. Urbanization raises aggregate actual and potential CO 2 emissions, but the effect is inconsistent for the transport sector. The findings have important implications for policy formulation. Copyright © 2018 Elsevier Ltd. All rights reserved.
State and Regional Control of Geological Carbon Sequestration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reitze, Arnold; Durrant, Marie
2011-03-01
The United States has economically recoverable coal reserves of about 261 billion tons, which is in excess of a 250-year supply based on 2009 consumption rates. However, in the near future the use of coal may be legally restricted because of concerns over the effects of its combustion on atmospheric carbon dioxide concentrations. Carbon capture and geologic sequestration offer one method to reduce carbon emissions from coal and other hydrocarbon energy production. While the federal government is providing increased funding for carbon capture and sequestration, recent congressional legislative efforts to create a framework for regulating carbon emissions have failed. However,more » regional and state bodies have taken significant actions both to regulate carbon and facilitate its capture and sequestration. This article explores how regional bodies and state government are addressing the technical and legal problems that must be resolved in order to have a viable carbon sequestration program. Several regional bodies have formed regulations and model laws that affect carbon capture and storage, and three bodies comprising twenty-three states—the Regional Greenhouse Gas Initiative, the Midwest Regional Greenhouse Gas Reduction Accord, and the Western Climate initiative—have cap-and-trade programs in various stages of development. State property, land use and environmental laws affect the development and implementation of carbon capture and sequestration projects, and unless federal standards are imposed, state laws on torts and renewable portfolio requirements will directly affect the liability and viability of these projects. This paper examines current state laws and legislative efforts addressing carbon capture and sequestration.« less
NASA Astrophysics Data System (ADS)
Augustin, C. M.; Broad, K.; Swart, P. K.
2011-12-01
It is estimated that carbon capture and storage (CCS) could be used to achieve between 15% and 55% of the carbon emission reductions necessary to avoid dangerous levels of climate change. It is also believed that achieving emission reduction goals will be less costly with CCS than without it. The expansion of active CCS sites over the past decade, from three to 53 demonstrates the value that industry sees in CCS as a transition technology for governments seeking to reduce their CO2 emissions. However, to continue developing CCS for industry scale implementation, it is essential to provide the regulatory certainty needed to foster energy industry wide adoption of CCS. Existing CCS regulatory regimes are inadequate, fragmented and contradictory. There is a need for comprehensive, unifying regulations for CCS that are flexible enough to adapt as the technology develops. Governments are limited by the fact that carbon capture and storage is a multidisciplinary issue that touches on the fields of oil drilling, groundwater quality, greenhouse gas management, air quality, and risk management. Though it is in part a technological, environmental and management issue there is also a complex political element to tackling the CCS problem. Due to its cross-cutting nature, CCS regulations should be based off the best practices and standards developed by industry stakeholders. Industry standards are stakeholder developed and consensus based, created through a democratic and collaborative process by bodies such as the International Standards Organization, the National Institutes of Standards and Testing (USA), ASTM International, and the Canadian Standards Organization. Standards can typically be broken down into six general categories: test methods, specifications, classifications, practices, guides, and terminology. These standards are created by stakeholders across the industry and across geographic boundaries to create an trade-wide, rather than nationwide, consensus and ensuring that the standards are international in scope. This paper examines regulatory issues post-capture, particularly the transport and geological storage of carbon dioxide and seeks to identify areas where relevant stakeholders should collaborate to develop a comprehensive list of industry standards and provides several case study examples.
How well is black carbon in the Arctic atmosphere captured by models?
NASA Astrophysics Data System (ADS)
Eckhardt, Sabine; Berntsen, Terje; Cherian, Ribu; Daskalakis, Nikos; Heyes, Chris; Hodnebrog, Øivind; Kanakidou, Maria; Klimont, Zbigniew; Law, Kathy; Lund, Marianne; Myhre, Gunnar; Myriokefalitakis, Stelios; Olivie, Dirk; Quaas, Johannes; Quennehen, Boris; Raut, Jean-Christophe; Samset, Bjørn; Schulz, Michael; Skeie, Ragnhild; Stohl, Andreas
2014-05-01
A correct representation of the spatial distribution of aerosols in atmospheric models is essential for realistic simulations of deposition and calculations of radiative forcing. It has been observed that transport of black carbon (BC) into the Arctic and scavenging is sometimes not captured accurately enough in chemistry transport models (CTM) as well as global circulation models (GCM). In this study we determine the discrepancies between measured equivalent BC (EBC) and modeled BC for several Arctic measurement stations as well as for Arctic aircraft campaigns. For this, we use the output of a set of 5 models based on the same emission dataset (ECLIPSE emissions, see eclipse.nilu.no) and evaluate the simulated concentrations at the measurement locations and times. Emissions are separated for different sources such as biomass burning, domestic heating, gas flaring, industry and the transport sector. We focus on the years 2008 and 2009, where many campaigns took place in the framework of the International Polar Year. Arctic stations like Barrow, Alert, Station Nord in Greenland and Zeppelin show a very pronounced winter/spring maximum in BC. While monthly averaged measured EBC values are around 80 ng/m^3, the models severely underestimate this with some models simulating only a small percentage of the observed values. During summer measured concentrations are a magnitude lower, and still underestimated by almost an order of magnitude in some models. However, the best models are correct within a factor of 2 in winter/spring and give realistic concentrations in summer. In order to get information on the vertical profile we used measurements from aircraft campaigns like ARCTAS, ARCPAC and HIPPO. It is found that BC in latitudes below 60 degrees is better captured by the models than BC at higher latitudes, even though it is overestimated at high altitudes. A systematic analysis of the performance of different models is presented. With the dataset we use we capture remote, polluted and fire-influenced conditions. We estimate the impact of model deficiencies on calculated BC radiative forcing by introducing scaling factors based on the model-measurement comparisons.
NASA Astrophysics Data System (ADS)
Aim-O, P.; Wongsawaeng, D.; Tancharakorn, S.; Sophon, M.
2017-09-01
High-density cement mixed with crumb rubber has been studied to be a gamma ray and neutron shielding material, especially for photonuclear reactions that may occur from accelerators where both types of radiation exist. The Buildup factors from gamma ray scattering, prompt and secondary gamma ray emissions from neutron capture and mechanical properties were evaluated. For buildup factor studies, two different geometries were used: narrow beam and broad beam. Prompt Gamma Neutron Activation Analysis (PGNAA) was carried out to determine the prompt and secondary gamma ray emissions. The compressive strength of samples was evaluated by using compression testing machine which was central point loading crushing test. The results revealed that addition of crumb rubber increased the buildup factor. Gamma ray spectra following PGNAA revealed no prompt or secondary gamma ray emission. Mechanical testing indicated that the compressive strength of the shielding material decreased with increasing volume percentage of crumb rubber.
Heavy Element Abundances in Planetary Nebulae from Deep Optical Echelle Spectroscopy
NASA Astrophysics Data System (ADS)
Mashburn, Amanda; Sterling, Nicholas C.; Dinerstein, Harriet L.; Garofali, Kristen; Jensema, Rachael; Turbyfill, Amanda; Wieser, Hannah-Marie N.; Reed, Evan C.; Redfield, Seth
2016-01-01
We present the abundances of neutron(n)-capture elements (atomic number Z > 30) and iron determined from deep optical echelle spectroscopy of 14 Galactic planetary nebulae (PNe). The spectra were obtained with the 2D-coudé spectrograph on the 2.7-m Harlan J. Smith telescope at McDonald Observatory. The abundances of n-capture elements can be enhanced in PNe due to slow n-capture nucleosynthesis in the progenitor asymptotic giant branch (AGB) stars. The high spectral resolution of these data (R = 36,700) allow most n-capture element emission lines to be resolved from other nebular and telluric features. We detect Kr in all of the observed PNe (with multiple ions detected in several objects), while Br, Rb, and Xe were each detected in 4--5 objects. Using the new Kr ionization correction factors (ICFs) of Sterling et al. (2015, ApJS, 218, 25), we find [Kr/O] abundances ranging from 0.05 to 1.1 dex. We utilize approximate ICFs for the other n-capture elements, and find slightly lower enrichments for Br and Rb (-0.1 to 0.7 dex), while Xe is enhanced relative to solar by factors of two to 30. The [Xe/Kr] ratios range from -0.3 to 1.4 dex, indicating a significant range in neutron exposures in PN progenitor stars. Interestingly, the largest [Xe/Kr] ratio is found in the thick-disk PN NGC 6644, which has a lower metallicity than the other observed PNe. We detect iron emission lines in all but one target. Fe can be depleted into dust grains in ionized nebulae, and its abundance thus provides key information regarding dust-to-gas ratios and grain destruction processes. We find that [Fe/O] ranges from -1.3 to -0.7 dex in the observed PNe, a smaller spread of depletion factors than found in recent studies (Delgado-Inglada & Rodriguez 2014, ApJ, 784, 173) though this may be due in part to our smaller sample. These data are part of a larger study of heavy elements in PNe, which will provide more accurate determinations of n-capture element abundances than previous estimates in several PNe, thereby providing key new constraints to models of AGB nucleosynthesis and Galactic chemical evolution. This work was supported by NSF awards AST-0708245 and AST-901432.
Pollutant in palm oil production process.
Hosseini, Seyed Ehsan; Abdul Wahid, Mazlan
2015-07-01
Palm oil mill effluent (POME) is a by-product of the palm industry and it releases large amounts of greenhouse gases (GHGs). Water systems are also contaminated by POME if it is released into nonstandard ponds or rivers where it endangers the lives of fish and water fowl. In this paper, the environmental bottlenecks faced by palm oil production were investigated by analyzing the data collected from wet extraction palm oil mills (POMs) located in Malaysia. Strategies for reducing pollution and technologies for GHG reduction from the wet extraction POMs were also proposed. Average GHG emissions produced from processing 1 ton of crude palm oil (CPO) was 1100 kg CO2eq. This amount can be reduced to 200 kg CO2eq by capturing biogases. The amount of GHG emissions from open ponds could be decreased from 225 to 25 kg CO2eq/MT CPO by covering the ponds. Installation of biogas capturing system can decrease the average of chemical oxygen demand (COD) to about 17,100 mg/L and stabilizing ponds in the final step could decrease COD to 5220 mg/L. Using a biogas capturing system allows for the reduction of COD by 80% and simultaneously using a biogas capturing system and by stabilizing ponds can mitigate COD by 96%. Other ways to reduce the pollution caused by POME, including the installation of wet scrubber vessels and increasing the performance of biogas recovery and biogas upgrading systems, are studied in this paper. Around 0.87 m3 POME is produced per 1 ton palm fruit milled. POME consists of around 2% oil, 2-4% suspended solid, 94-96% water. In palm oil mills, more than 90% of GHGs were emitted from POME. From 1 ton crude palm oil, 1100 kg CO2eq GHGs are generated, which can be reduced to 200 kg CO2eq by installation of biogas capturing equipment.
Lan, Xin; Talbot, Robert; Laine, Patrick; Torres, Azucena; Lefer, Barry; Flynn, James
2015-09-01
Atmospheric mercury emissions in the Barnett Shale area were studied by employing both stationary measurements and mobile laboratory surveys. Stationary measurements near the Engle Mountain Lake showed that the median mixing ratio of total gaseous mercury (THg) was 138 ppqv (140 ± 29 ppqv for mean ± S.D.) during the June 2011 study period. A distinct diurnal variation pattern was observed in which the highest THg levels appeared near midnight, followed by a monotonic decrease until midafternoon. The influence of oil and gas (ONG) emissions was substantial in this area, as inferred from the i-pentane/n-pentane ratio (1.17). However, few THg plumes were captured by our mobile laboratory during a ∼3700 km survey with detailed downwind measurements from 50 ONG facilities. One compressor station and one natural gas condensate processing facility were found to have significant THg emissions, with maximum THg levels of 963 and 392 ppqv, respectively, and the emissions rates were estimated to be 7.9 kg/yr and 0.3 kg/yr, respectively. Our results suggest that the majority of ONG facilities in this area are not significant sources of THg; however, it is highly likely that a small number of these facilities contribute a relatively large amount of emissions in the ONG sector.
Nuclear structure and weak rates of heavy waiting point nuclei under rp-process conditions
NASA Astrophysics Data System (ADS)
Nabi, Jameel-Un; Böyükata, Mahmut
2017-01-01
The structure and the weak interaction mediated rates of the heavy waiting point (WP) nuclei 80Zr, 84Mo, 88Ru, 92Pd and 96Cd along N = Z line were studied within the interacting boson model-1 (IBM-1) and the proton-neutron quasi-particle random phase approximation (pn-QRPA). The energy levels of the N = Z WP nuclei were calculated by fitting the essential parameters of IBM-1 Hamiltonian and their geometric shapes were predicted by plotting potential energy surfaces (PESs). Half-lives, continuum electron capture rates, positron decay rates, electron capture cross sections of WP nuclei, energy rates of β-delayed protons and their emission probabilities were later calculated using the pn-QRPA. The calculated Gamow-Teller strength distributions were compared with previous calculation. We present positron decay and continuum electron capture rates on these WP nuclei under rp-process conditions using the same model. For the rp-process conditions, the calculated total weak rates are twice the Skyrme HF+BCS+QRPA rates for 80Zr. For remaining nuclei the two calculations compare well. The electron capture rates are significant and compete well with the corresponding positron decay rates under rp-process conditions. The finding of the present study supports that electron capture rates form an integral part of the weak rates under rp-process conditions and has an important role for the nuclear model calculations.
ERIC Educational Resources Information Center
Liou, Wei-Kai; Bhagat, Kaushal Kumar; Chang, Chun-Yen
2018-01-01
The aim of this study is to design and implement a digital interactive globe system (DIGS), by integrating low-cost equipment to make DIGS cost-effective. DIGS includes a data processing unit, a wireless control unit, an image-capturing unit, a laser emission unit, and a three-dimensional hemispheric body-imaging screen. A quasi-experimental study…
Infrared non-destructive evaluation method and apparatus
Baleine, Erwan; Erwan, James F; Lee, Ching-Pang; Stinelli, Stephanie
2014-10-21
A method of nondestructive evaluation and related system. The method includes arranging a test piece (14) having an internal passage (18) and an external surface (15) and a thermal calibrator (12) within a field of view (42) of an infrared sensor (44); generating a flow (16) of fluid characterized by a fluid temperature; exposing the test piece internal passage (18) and the thermal calibrator (12) to fluid from the flow (16); capturing infrared emission information of the test piece external surface (15) and of the thermal calibrator (12) simultaneously using the infrared sensor (44), wherein the test piece infrared emission information includes emission intensity information, and wherein the thermal calibrator infrared emission information includes a reference emission intensity associated with the fluid temperature; and normalizing the test piece emission intensity information against the reference emission intensity.
Pathways to Carbon-Negative Liquid Biofuels
NASA Astrophysics Data System (ADS)
Woolf, D.; Lehmann, J.
2017-12-01
Many climate change mitigation scenarios assume that atmospheric carbon dioxide removal will be delivered at scale using bioenergy power generation with carbon capture and storage (BECCS). However, other pathways to negative emission technologies (NETs) in the energy sector are possible, but have received relatively little attention. Given that the costs, benefits and life-cycle emissions of technologies vary widely, more comprehensive analyses of the policy options for NETs are critical. This study provides a comparative assessment of the potential pathways to carbon-negative liquid biofuels. It is often assumed that that decarbonisation of the transport sector will include use of liquid biofuels, particularly for applications that are difficult to electrify such as aviation and maritime transport. However, given that biomass and land on which to grow it sustainably are limiting factors in the scaling up of both biofuels and NETs, these two strategies compete for shared factors of production. One way to circumvent this competition is carbon-negative biofuels. Because capture of exhaust CO2 in the transport sector is impractical, this will likely require carbon capture during biofuel production. Potential pathways include, for example, capture of CO2 from fermentation, or sequestration of biochar from biomass pyrolysis in soils, in combination with thermochemical or bio-catalytic conversion of syngas to alcohols or alkanes. Here we show that optimal pathway selection depends on specific resource constraints. As land availability becomes increasingly limiting if bioenergy is scaled up—particularly in consideration that abandoned degraded land is widely considered to be an important resource that does not compete with food fiber or habitat—then systems which enhance land productivity by increasing soil fertility using soil carbon sequestration become increasingly preferable compared to bioenergy systems that deplete or degrade the land resource on which they depend.
Integrating Algae with Bioenergy Carbon Capture and Storage (ABECCS) Increases Sustainability
NASA Astrophysics Data System (ADS)
Beal, Colin M.; Archibald, Ian; Huntley, Mark E.; Greene, Charles H.; Johnson, Zackary I.
2018-03-01
Bioenergy carbon capture and storage (BECCS) has been proposed to reduce atmospheric CO2 concentrations, but concerns remain about competition for arable land and freshwater. The synergistic integration of algae production, which does not require arable land or freshwater, with BECCS (called "ABECCS") can reduce CO2 emissions without competing with agriculture. This study presents a technoeconomic and life-cycle assessment for colocating a 121-ha algae facility with a 2,680-ha eucalyptus forest for BECCS. The eucalyptus biomass fuels combined heat and power (CHP) generation with subsequent amine-based carbon capture and storage (CCS). A portion of the captured CO2 is used for growing algae and the remainder is sequestered. Biomass combustion supplies CO2, heat, and electricity, thus increasing the range of sites suitable for algae cultivation. Economic, energetic, and environmental impacts are considered. The system yields as much protein as soybeans while generating 61.5 TJ of electricity and sequestering 29,600 t of CO2 per year. More energy is generated than consumed and the freshwater footprint is roughly equal to that for soybeans. Financial break-even is achieved for product value combinations that include 1) algal biomass sold for 1,400/t (fishmeal replacement) with a 68/t carbon credit and 2) algal biomass sold for 600/t (soymeal replacement) with a 278/t carbon credit. Sensitivity analysis shows significant reductions to the cost of carbon sequestration are possible. The ABECCS system represents a unique technology for negative emissions without reducing protein production or increasing water demand, and should therefore be included in the suite of technologies being considered to address global sustainability.
Xing, Tiancai; Jiang, Qichuan; Ma, Xuejiao
2017-10-13
With the Paris Agreement coming into effect, China, as the largest CO₂ emitter in the world, will be facing greater pressure to reduce its carbon emissions. This paper discusses how to solve this issue from the perspective of financial development in China. Although many studies have analyzed its impact on carbon emissions, the conclusions are contradictory. A major criticism of the existing studies is the reasonability of the selection of appropriate indicators and panel estimation techniques. Almost all studies use only one or limited indicators to represent the financial development and ignore the cross-sectional dependence. To fulfil the gaps mentioned above, a financial development index system is built, and with the framework of the STIRPAT (Stochastic impacts by regression on population, affluence, and technology) model, this paper applies an ARDL approach to investigating the long-run relationship between financial development and carbon emissions and a dynamic panel error-corrected model to capture the short-run impact. The empirical results show that financial development can improve carbon emissions, and such impact not only shows a regional difference but also reflects the features of stage differences. Additionally, based on the discussion on seven specific aspects of financial development, our findings can be helpful for policy makers to enact corresponding policies to realize the goal of reducing carbon emissions in China.
Xing, Tiancai; Jiang, Qichuan
2017-01-01
With the Paris Agreement coming into effect, China, as the largest CO2 emitter in the world, will be facing greater pressure to reduce its carbon emissions. This paper discusses how to solve this issue from the perspective of financial development in China. Although many studies have analyzed its impact on carbon emissions, the conclusions are contradictory. A major criticism of the existing studies is the reasonability of the selection of appropriate indicators and panel estimation techniques. Almost all studies use only one or limited indicators to represent the financial development and ignore the cross-sectional dependence. To fulfil the gaps mentioned above, a financial development index system is built, and with the framework of the STIRPAT (Stochastic impacts by regression on population, affluence, and technology) model, this paper applies an ARDL approach to investigating the long-run relationship between financial development and carbon emissions and a dynamic panel error-corrected model to capture the short-run impact. The empirical results show that financial development can improve carbon emissions, and such impact not only shows a regional difference but also reflects the features of stage differences. Additionally, based on the discussion on seven specific aspects of financial development, our findings can be helpful for policy makers to enact corresponding policies to realize the goal of reducing carbon emissions in China. PMID:29027983
USDA-ARS?s Scientific Manuscript database
Two experiments were conducted to evaluate the effect of bait delivery rate on methane emission estimates measured by a GreenFeed system (GFS; C-Lock, Inc., Rapid City, SD). The manufacture recommends that cattle have a minimum visit time of 3 minutes so that at least 3 eructations are captured to ...
40 CFR 63.3370 - How do I demonstrate compliance with the emission standards?
Code of Federal Regulations, 2014 CFR
2014-07-01
... equivalent allowable organic HAP (Equation 13a or b of § 63.3370). (4) Use of a capture system and control... control devices (i) Average equivalent organic HAP emission rate does not exceed 0.2 kg organic HAP per kg... material applied on the web coating line or group of web coating lines controlled by a common control...
40 CFR 63.3370 - How do I demonstrate compliance with the emission standards?
Code of Federal Regulations, 2012 CFR
2012-07-01
... equivalent allowable organic HAP (Equation 13a or b of § 63.3370). (4) Use of a capture system and control... control devices (i) Average equivalent organic HAP emission rate does not exceed 0.2 kg organic HAP per kg... material applied on the web coating line or group of web coating lines controlled by a common control...
40 CFR 63.3370 - How do I demonstrate compliance with the emission standards?
Code of Federal Regulations, 2013 CFR
2013-07-01
... equivalent allowable organic HAP (Equation 13a or b of § 63.3370). (4) Use of a capture system and control... control devices (i) Average equivalent organic HAP emission rate does not exceed 0.2 kg organic HAP per kg... material applied on the web coating line or group of web coating lines controlled by a common control...
40 CFR 63.3920 - What reports must I submit?
Code of Federal Regulations, 2010 CFR
2010-07-01
... limitation (including any periods when emissions bypassed the add-on control device and were diverted to the... month by emission capture systems and add-on control devices using Equations 1 and 1A through 1D of § 63... description of the CPMS. (v) The date of the latest CPMS certification or audit. (vi) The date and time that...
NASA Astrophysics Data System (ADS)
Cumbee, R. S.; Mullen, P. D.; Lyons, D.; Shelton, R. L.; Fogle, M.; Schultz, D. R.; Stancil, P. C.
2018-01-01
The fundamental collisional process of charge exchange (CX) has been established as a primary source of X-ray emission from the heliosphere, planetary exospheres, and supernova remnants. In this process, X-ray emission results from the capture of an electron by a highly charged ion from a neutral atom or molecule, to form a highly excited, high-charge state ion. As the captured electron cascades down to the lowest energy level, photons are emitted, including X-rays. To provide reliable CX-induced X-ray spectral models to realistically simulate these environments, line ratios and spectra are computed using theoretical CX cross sections obtained with the multi-channel Landau-Zener, atomic-orbital close-coupling, molecular-orbital close-coupling, and classical trajectory Monte Carlo methods for various collisional velocities relevant to astrophysics. X-ray spectra were computed for collisions of bare and H-like C to Al ions with H, He, and H2 with results compared to available experimental data. Using these line ratios, XSPEC models of CX emission in the northeast rim of the Cygnus Loop supernova remnant and the heliosphere are shown as examples with ion velocity dependence.
NASA Astrophysics Data System (ADS)
Hashim, Akasha; Khalid, Amir; Sapit, Azwan; Samsudin, Dahrum
2016-11-01
There are many technologies about exhaust emissions reduction for wide variety of spark ignition (SI) engine have been considered as the improvement throughout the combustion process. The stricter on legislation of emission and demands of lower fuel consumption needs to be priority in order to satisfy the demand of emission quality. Besides, alternative fuel such as methanol-gasoline blends is used as working fluid in this study due to its higher octane number and self-sustain concept which capable to contribute positive effect to the combustion process. The purpose of this study is to investigate the effects of methanol-gasoline fuel with different blending ratio and variant ambient pressures on flame development and emission for gasoline engine. An experimental study is carried towards to the flame development of methanol-gasoline fuel in a constant volume chamber. Schlieren optical visualization technique is a visual process that used when high sensitivity is required to photograph the flow of fluids of varying density used for captured the combustion images in the constant volume chamber and analysed through image processing technique. Apart from that, the result showed combustion burn rate increased when the percentage of methanol content in gasoline increased. Thus, high percentage of methanol-gasoline blends gave greater flame development area. Moreover, the emissions of CO, NOX and HC are performed a reduction when the percentage of methanol content in gasoline is increased. Contrarily, the emission of Carbon dioxide, CO2 is increased due to the combustion process is enhanced.
Investigation of tracer emission and transport in GEOS-5 during ARCTAS
NASA Astrophysics Data System (ADS)
Bian, H.; Chin, M.; Kawa, S. R.; Colarco, P. R.; Nielsen, E.; Pawson, S.; Kucsera, T.; da Silva, A.; Chu, A. D.
2009-12-01
We examine the emission and transport of trace gases and their impact on the Arctic environment during two ARCTAS flights. One captures Asian anthropogenic pollution and one focuses on the impact of biomass burning. Three approaches are used in our study. First, the comparison of GEOS5 CO and aerosol with observations from the two ARCTAS flights provides evaluation of the model’s sources, sinks, chemistry, and transport. Second, backward trajectories from the aircraft measurements trace the pollutant samples to their source regions and forward trajectories applied to the emissions at the pollutant origin target the final destination of the pollutant. Third, a high meridonal index (HMI) approach, which emphasizes the part of a blocking where the jet stream curves northwards, will be used to link the long-range pollutant transport from northern hemispheric mid-latitudes to the Arctic region.
NASA Astrophysics Data System (ADS)
Itahashi, S.; Uno, I.; Irie, H.; Kurokawa, J.; Ohara, T.
2013-04-01
Satellite observations of the tropospheric NO2 vertical column density (VCD) are closely correlated to surface NOx emissions and can thus be used to estimate the latter. In this study, the NO2 VCDs simulated by a regional chemical transport model with data from the updated Regional Emission inventory in ASia (REAS) version 2.1 were validated by comparison with multi-satellite observations (GOME, SCIAMACHY, GOME-2, and OMI) between 2000 and 2010. Rapid growth in NO2 VCD driven by expansion of anthropogenic NOx emissions was revealed above the central eastern China region, except during the economic downturn. In contrast, slightly decreasing trends were captured above Japan. The modeled NO2 VCDs using the updated REAS emissions reasonably reproduced the annual trends observed by multi-satellites, suggesting that the NOx emissions growth rate estimated by the updated inventory is robust. On the basis of the close linear relationship of modeled NO2 VCD, observed NO2 VCD, and anthropogenic NOx emissions, the NOx emissions in 2009 and 2010 were estimated. It was estimated that the NOx emissions from anthropogenic sources in China beyond doubled between 2000 and 2010, reflecting the strong growth of anthropogenic emissions in China with the rapid recovery from the economic downturn during late 2008 and mid-2009.
Nielsen, Claus J; Herrmann, Hartmut; Weller, Christian
2012-10-07
This critical review addresses the atmospheric gas phase and aqueous phase amine chemistry that is relevant to potential emissions from amine-based carbon capture and storage (CCS). The focus is on amine, nitrosamine and nitramine degradation, and nitrosamine and nitramine formation processes. A comparison between the relative importance of the various atmospheric sinks for amines, nitrosamines and nitramines is presented.
CaO-based CO2 sorbents: from fundamentals to the development of new, highly effective materials.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fitzgerald, David; Vidal, Rafael; Russell, Tania
2014-12-31
The results of the preliminary environmental, health and safety (EH&S) risk assessment for an enzyme-activated potassium carbonate (K2CO3) solution post-combustion CO2 capture (PCC) plant, integrated with a subcritical pulverized coal (PC) power plant, are presented. The expected emissions during normal steady-state operation have been estimated utilizing models of the PCC plant developed in AspenTech’s AspenPlus® software, bench scale test results from the University of Kentucky, and industrial experience of emission results from a slipstream PCC plant utilizing amine based solvents. A review of all potential emission species and their sources was undertaken that identified two credible emission sources, the absorbermore » off-gas that is vented to atmosphere via a stack and the waste removed from the PCC plant in the centrifuge used to reclaim enzyme and solvent. The conditions and compositions of the emissions were calculated and the potential EH&S effects were considered as well as legislative compliance requirements. Potential mitigation methods for emissions during normal operation have been proposed and solutions to mitigate uncontrolled releases of species have been considered. The potential emissions were found to pose no significant EH&S concerns and were compliant with the Federal legislation reviewed. The limitations in predicting full scale plant performance from bench scale tests have been noted and further work on a larger scale test unit is recommended to reduce the level of uncertainty.« less
Harvesting Electricity From Wasted Heat
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schwede, Jared
Scientists as SLAC National Laboratory explain the concept, Photon Enhanced Thermionic Emission (PETE), and how this process can capture more energy from photovoltaic panels by harnessing heat energy from sunlight.
Harvesting Electricity From Wasted Heat
Schwede, Jared
2018-01-16
Scientists as SLAC National Laboratory explain the concept, Photon Enhanced Thermionic Emission (PETE), and how this process can capture more energy from photovoltaic panels by harnessing heat energy from sunlight.
40 CFR 63.5860 - How do I demonstrate initial compliance with the standards?
Code of Federal Regulations, 2010 CFR
2010-07-01
... CATEGORIES National Emissions Standards for Hazardous Air Pollutants: Reinforced Plastic Composites... Factor, Percent Reduction, and Capture Efficiency Calculation Procedures for Continuous Lamination...
Quantifying the isotopic composition of NOx emission sources: An analysis of collection methods
NASA Astrophysics Data System (ADS)
Fibiger, D.; Hastings, M.
2012-04-01
We analyze various collection methods for nitrogen oxides, NOx (NO2 and NO), used to evaluate the nitrogen isotopic composition (δ15N). Atmospheric NOx is a major contributor to acid rain deposition upon its conversion to nitric acid; it also plays a significant role in determining air quality through the production of tropospheric ozone. NOx is released by both anthropogenic (fossil fuel combustion, biomass burning, aircraft emissions) and natural (lightning, biogenic production in soils) sources. Global concentrations of NOx are rising because of increased anthropogenic emissions, while natural source emissions also contribute significantly to the global NOx burden. The contributions of both natural and anthropogenic sources and their considerable variability in space and time make it difficult to attribute local NOx concentrations (and, thus, nitric acid) to a particular source. Several recent studies suggest that variability in the isotopic composition of nitric acid deposition is related to variability in the isotopic signatures of NOx emission sources. Nevertheless, the isotopic composition of most NOx sources has not been thoroughly constrained. Ultimately, the direct capture and quantification of the nitrogen isotopic signatures of NOx sources will allow for the tracing of NOx emissions sources and their impact on environmental quality. Moreover, this will provide a new means by which to verify emissions estimates and atmospheric models. We present laboratory results of methods used for capturing NOx from air into solution. A variety of methods have been used in field studies, but no independent laboratory verification of the efficiencies of these methods has been performed. When analyzing isotopic composition, it is important that NOx be collected quantitatively or the possibility of fractionation must be constrained. We have found that collection efficiency can vary widely under different conditions in the laboratory and fractionation does not vary predictably with collection efficiency. For example, prior measurements frequently utilized triethanolamine solution for collecting NOx, but the collection efficiency was found to drop quickly as the solution aged. The most promising method tested is a NaOH/KMnO4 solution (Margeson and Knoll, Anal. Chem., 1985) which can collect NOx quantitatively from the air. Laboratory tests of previously used methods, along with progress toward creating a suitable and verifiable field deployable collection method will be presented.
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
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
The Effect of Emissions Trading And Carbon Sequestration on The Cost Of CO2 Emissions Mitigation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mahasenan, Natesan; Scott, Michael J.; Smith, Steven J.
2002-08-05
The deployment of carbon capture and sequestration (CC&S) technologies is greatly affected by the marginal cost of controlling carbon emissions (also the value of carbon, when emissions permits are traded). Emissions limits that are more stringent in the near term imply higher near-term carbon values and therefore encourage the local development and deployment of CC&S technologies. In addition, trade in emissions obligations lowers the cost of meeting any regional or global emissions limit and so affects the rate of penetration of CC&S technologies. We examine the effects of the availability of sequestration opportunities and emissions trading (either within select regionsmore » or globally) on the cost of emissions mitigation and compliance with different emissions reduction targets for the IPCC SRES scenarios. For each base scenario and emissions target, we examine the issues outlined above and present quantitative estimates for the impacts of trade and the availability of sequestration opportunities in meeting emissions limitation obligations.« less
NASA Astrophysics Data System (ADS)
Banzhaf, S.; Schaap, M.; Kranenburg, R.; Manders, A. M. M.; Segers, A. J.; Visschedijk, A. J. H.; Denier van der Gon, H. A. C.; Kuenen, J. J. P.; van Meijgaard, E.; van Ulft, L. H.; Cofala, J.; Builtjes, P. J. H.
2015-04-01
In this study we present a dynamic model evaluation of chemistry transport model LOTOS-EUROS (LOng Term Ozone Simulation - EURopean Operational Smog) to analyse the ability of the model to reproduce observed non-linear responses to emission changes and interannual variability of secondary inorganic aerosol (SIA) and its precursors over Europe from 1990 to 2009. The 20 year simulation was performed using a consistent set of meteorological data provided by RACMO2 (Regional Atmospheric Climate MOdel). Observations at European rural background sites have been used as a reference for the model evaluation. To ensure the consistency of the used observational data, stringent selection criteria were applied, including a comprehensive visual screening to remove suspicious data from the analysis. The LOTOS-EUROS model was able to capture a large part of the seasonal and interannual variability of SIA and its precursors' concentrations. The dynamic evaluation has shown that the model is able to simulate the declining trends observed for all considered sulfur and nitrogen components following the implementation of emission abatement strategies for SIA precursors over Europe. Both the observations and the model show the largest part of the decline in the 1990s, while smaller concentration changes and an increasing number of non-significant trends are observed and modelled between 2000 and 2009. Furthermore, the results confirm former studies showing that the observed trends in sulfate and total nitrate concentrations from 1990 to 2009 are lower than the trends in precursor emissions and precursor concentrations. The model captured well these non-linear responses to the emission changes. Using the LOTOS-EUROS source apportionment module, trends in the formation efficiency of SIA have been quantified for four European regions. The exercise has revealed a 20-50% more efficient sulfate formation in 2009 compared to 1990 and an up to 20% more efficient nitrate formation per unit nitrogen oxide emission, which added to the explanation of the non-linear responses. However, we have also identified some weaknesses in the model and the input data. LOTOS-EUROS underestimates the observed nitrogen dioxide concentrations throughout the whole time period, while it overestimates the observed nitrogen dioxide concentration trends. Moreover, model results suggest that the emission information of the early 1990s used in this study needs to be improved concerning magnitude and spatial distribution.
NASA Astrophysics Data System (ADS)
Banzhaf, S.; Schaap, M.; Kranenburg, R.; Manders, A. M. M.; Segers, A. J.; Visschedijk, A. H. J.; Denier van der Gon, H. A. C.; Kuenen, J. J. P.; van Meijgaard, E.; van Ulft, L. H.; Cofala, J.; Builtjes, P. J. H.
2014-07-01
In this study we present a dynamic model evaluation of the chemistry transport model LOTOS-EUROS to analyse the ability of the model to reproduce observed non-linear responses to emission changes and interannual variability of secondary inorganic aerosol (SIA) and its precursors over Europe from 1990 to 2009. The 20 year simulation was performed using a consistent set of meteorological data provided by the regional climate model RACMO2. Observations at European rural background sites have been used as reference for the model evaluation. To ensure the consistency of the used observational data stringent selection criteria were applied including a comprehensive visual screening to remove suspicious data from the analysis. The LOTOS-EUROS model was able to capture a large part of the day-to-day, seasonal and interannual variability of SIA and its precursors' concentrations. The dynamic evaluation has shown that the model is able to simulate the declining trends observed for all considered sulphur and nitrogen components following the implementation of emission abatement strategies for SIA precursors over Europe. Both, the observations and the model show the largest part of the decline in the 1990's while smaller concentration changes and an increasing number of non-significant trends are observed and modelled between 2000-2009. Furthermore, the results confirm former studies showing that the observed trends in sulphate and total nitrate concentrations from 1990 to 2009 are significantly lower than the trends in precursor emissions and precursor concentrations. The model captured these non-linear responses to the emission changes well. Using the LOTOS-EUROS source apportionment module trends in formation efficiency of SIA have been quantified for four European regions. The exercise has revealed a 20-50% more efficient sulphate formation in 2009 compared to 1990 and an up to 20% more efficient nitrate formation per unit nitrogen oxide emission, which added to the explanation of the non-linear responses. However, we have also identified some weaknesses to the model and the input data. LOTOS-EUROS underestimates the observed nitrogen dioxide concentrations throughout the whole time period, while it overestimates the observed nitrogen dioxide concentration trends. Moreover, model results suggest that the emission information of the early 1990's used in this study needs to be improved concerning magnitude and spatial distribution.
Yoshida, Hiroko; Clavreul, Julie; Scheutz, Charlotte; Christensen, Thomas H
2014-06-01
A Life Cycle Assessment (LCA) of a municipal wastewater treatment plant (WWTP) was conducted to illustrate the effect of an emission inventory data collection scheme on the outcomes of an environmental impact assessment. Due to their burden in respect to data collection, LCAs often rely heavily on existing emission and operational data, which are gathered under either compulsory monitoring or reporting requirements under law. In this study, an LCA was conducted using three input data sources: Information compiled under compulsory disclosure requirements (the European Pollutant Release and Transfer Registry), compliance with national discharge limits, and a state-of-the-art emission data collection scheme conducted at the same WWTP. Parameter uncertainty for each collection scheme was assessed through Monte Carlo simulation. The comparison of the results confirmed that LCA results depend heavily on input data coverage. Due to the threshold on reporting value, the E-PRTR did not capture the impact for particulate matter emission, terrestrial acidification, or terrestrial eutrophication. While the current practice can capture more than 90% of non-carcinogenic human toxicity and marine eutrophication, an LCA based on the data collection scheme underestimates impact potential due to limitations of substance coverage. Besides differences between data collection schemes, the results showed that 3-13,500% of the impacts came from background systems, such as from the provisioning of fuel, electricity, and chemicals, which do not need to be disclosed currently under E-PRTR. The incidental release of pollutants was also assessed by employing a scenario-based approach, the results of which demonstrated that these non-routine emissions could increase overall WWTP greenhouse gas emissions by between 113 and 210%. Overall, current data collection schemes have the potential to provide standardized data collection and form the basis for a sound environmental impact assessment, but several improvements are recommended, including the additional collection of energy and chemical usage data, the elimination of a reporting threshold, the expansion of substance coverage, and the inclusion of non-point fugitive gas emissions. Copyright © 2014 Elsevier Ltd. All rights reserved.
March, Anne Marie; Assefa, Tadesse A.; Boemer, Christina; ...
2017-01-17
Here we probe the dynamics of valence electrons in photoexcited [Fe(terpy) 2] 2+ in solution to gain deeper insight into the Fe-ligand bond changes. We use hard X-ray emission spectroscopy (XES), which combines element specificity and high penetration with sensitivity to orbital structure, making it a powerful technique for molecular studies in a wide variety of environments. A picosecond-time-resolved measurement of the complete Is X-ray emission spectrum captures the transient photoinduced changes and includes the weak valence-to-core (vtc) emission lines that correspond to transitions from occupied valence orbitals to the nascent core-hole. Vtc-XES offers particular insight into the molecular orbitalsmore » directly involved in the light-driven dynamics; a change in the metal-ligand orbital overlap results in an intensity reduction and a blue energy shift in agreement with our theoretical calculations and more subtle features at the highest energies reflect changes in the frontier orbital populations.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
March, Anne Marie; Assefa, Tadesse A.; Boemer, Christina
Here we probe the dynamics of valence electrons in photoexcited [Fe(terpy) 2] 2+ in solution to gain deeper insight into the Fe-ligand bond changes. We use hard X-ray emission spectroscopy (XES), which combines element specificity and high penetration with sensitivity to orbital structure, making it a powerful technique for molecular studies in a wide variety of environments. A picosecond-time-resolved measurement of the complete Is X-ray emission spectrum captures the transient photoinduced changes and includes the weak valence-to-core (vtc) emission lines that correspond to transitions from occupied valence orbitals to the nascent core-hole. Vtc-XES offers particular insight into the molecular orbitalsmore » directly involved in the light-driven dynamics; a change in the metal-ligand orbital overlap results in an intensity reduction and a blue energy shift in agreement with our theoretical calculations and more subtle features at the highest energies reflect changes in the frontier orbital populations.« less
Radiation effects in accelerator components
NASA Astrophysics Data System (ADS)
Borden, M. J.
1995-05-01
A review of basic radiation effects is presented. The fundamental definitions of radioactivity are given for alpha, beta, positron decay, gamma-ray emission and electron capture. The interaction of neutrons with material is covered including: absorption through radiative capture, neutron-proton interaction, alpha particle emission, neutron-multi-neutron reactions and fission. Basic equations defining inelastic and elastic scattering are presented with examples of neutron energy loss per collision for several elements. Photon interactions are considered for gamma-rays and x-rays. Photoelectric collisions, the Compton effect and pair production are reviewed. Electron-proton interactions are discussed with emphasis placed on defect production. Basic displacement damage mechanisms for photon and particle interaction are presented. Several examples of radiation effects to plastics, electronics and ceramics are presented. Extended references are given for each example.
NASA Astrophysics Data System (ADS)
Quan, Xie; Chen, Shuo; Platzer, Bernhard; Chen, Jingwen; Gfrerer, Marion
2002-01-01
Water and sediment samples were screened simultaneously for the presence of polychlorinated organic compounds using gas chromatography (GC) coupled with an micro electron capture detector (μ-ECD) and a newly developed helium plasma based on a micro-atomic emission detector (μ-AED). The GC column effluent was split 15:85 between two detectors. In this way, two chromatograms, one obtained by μ-ECD and another by μ-AED, were recorded simultaneously. α-, β-hexachlorocyclohexane and p, p'-DDE were detected. RSDs of the monitoring results from the two detection methods were <20% for the three compounds. A detection limit of 8.5 pg and at least 3 orders of magnitude of linear range for μ-AED was observed.
NASA Astrophysics Data System (ADS)
Duc, Tran Thien; Pozina, Galia; Amano, Hiroshi; Monemar, Bo; Janzén, Erik; Hemmingsson, Carl
2016-07-01
Deep levels in Mg-doped GaN grown by metal organic chemical vapor deposition (MOCVD), undoped GaN grown by MOCVD, and halide vapor phase epitaxy (HVPE)-grown GaN have been studied using deep level transient spectroscopy and minority charge carrier transient spectroscopy on Schottky diodes. One hole trap, labeled HT1, was detected in the Mg-doped sample. It is observed that the hole emission rate of the trap is enhanced by increasing electric field. By fitting four different theoretical models for field-assisted carrier emission processes, the three-dimensional Coulombic Poole-Frenkel (PF) effect, three-dimensional square well PF effect, phonon-assisted tunneling, and one-dimensional Coulombic PF effect including phonon-assisted tunneling, it is found that the one-dimensional Coulombic PF model, including phonon-assisted tunneling, is consistent with the experimental data. Since the trap exhibits the PF effect, we suggest it is acceptorlike. From the theoretical model, the zero field ionization energy of the trap and an estimate of the hole capture cross section have been determined. Depending on whether the charge state is -1 or -2 after hole emission, the zero field activation energy Ei 0 is 0.57 eV or 0.60 eV, respectively, and the hole capture cross section σp is 1.3 ×10-15c m2 or 1.6 ×10-16c m2 , respectively. Since the level was not observed in undoped GaN, it is suggested that the trap is associated with an Mg related defect.
Carbon dioxide emission and economic growth of China-the role of international trade.
Boamah, Kofi Baah; Du, Jianguo; Bediako, Isaac Asare; Boamah, Angela Jacinta; Abdul-Rasheed, Alhassan Alolo; Owusu, Samuel Mensah
2017-05-01
This study investigates the role of international trade in mitigating carbon dioxide emission as a nation economically advances. This study disaggregated the international trade into total exports and total imports. A multivariate model framework was estimated for the time series data for the period of 1970-2014. The quantile regression detected all the essential relationship, which hitherto, the traditional ordinary least squares could not capture. A cointegration relationship was confirmed using the Johansen cointegration model. The findings of the Granger causality revealed the presence of a uni-directional Granger causality running from energy consumption to economic growth; from import to economic growth; from imports to exports; and from urbanisation to economic growth, exports and imports. Our study established the presence of long-run relationships amongst carbon dioxide emission, economic growth, energy consumption, imports, exports and urbanisation. A bootstrap method was further utilised to reassess the evidence of the Granger causality, of which the results affirmed the Granger causality in the long run. This study confirmed a long-run N-shaped relationship between economic growth and carbon emission, under the estimated cubic environmental Kuznet curve framework, from the perspective of China. The recommendation therefore is that China as export leader should transform its trade growth mode by reducing the level of carbon dioxide emission and strengthening its international cooperation as it embraces more environmental protectionisms.
Ye, Liu; Ni, Bing-Jie; Law, Yingyu; Byers, Craig; Yuan, Zhiguo
2014-01-01
The quantification of nitrous oxide (N2O) emissions from open-surface wastewater treatment systems with surface aerators is difficult as emissions from the surface aerator zone cannot be easily captured by floating hoods. In this study, we propose and demonstrate a novel methodology to estimate N2O emissions from such systems through determination of the N2O transfer coefficient (kLa) induced by surface aerators based on oxygen balance for the entire system. The methodology is demonstrated through its application to a full-scale open oxidation ditch wastewater treatment plant with surface aerators. The estimated kLa profile based on a month-long measurement campaign for oxygen balance, intensive monitoring of dissolved N2O profiles along the oxidation ditch over a period of four days, together with mathematical modelling, enabled to determine the N2O emission factor from this treatment plant (0.52 ± 0.16%). Majority of the N2O emission was found to occur in the surface aerator zone, which would be missed if the gas hood method was applied alone. Copyright © 2013 Elsevier Ltd. All rights reserved.
Housing and mobility demands of individual households and their life cycle assessment.
Saner, Dominik; Heeren, Niko; Jäggi, Boris; Waraich, Rashid A; Hellweg, Stefanie
2013-06-04
Household consumption, apart from governmental consumption, is the main driver of worldwide economy. Attached to each household purchase are economic activities along the preceding supply chain, with the associated resource use and emissions. A method to capture and assess all these resource uses and emissions is life cycle assessment. We developed a model for the life cycle assessment of housing and land-based mobility (excluding air travel) consumption of individual households a small village in Switzerland. Statistical census and dwelling register data are the foundations of the model. In a case study performed on a midsized community, we found a median value of greenhouse gas emissions of 3.12 t CO2 equiv and a mean value of 4.30 t CO2 equiv per capita and year for housing and mobility. Twenty-one percent of the households in the investigated region were responsible for 50% of the total greenhouse gas emissions, meaning that if their emissions could be halved the total emissions of the community would be reduced by 25%. Furthermore, a cluster analysis revealed that driving factors for large environmental footprints are demands of large living area heated by fossil energy carriers, as well as large demands of motorized private transportation.
Mazumdar, Prativa; Maity, Samir; Shyamal, Milan; Das, Debasish; Sahoo, Gobinda Prasad; Misra, Ajay
2016-03-14
A heteroatom containing organic fluorophore 6,7-dimethyl-2,3-bis-(2-pyridyl)-quinoxaline (BPQ) is weakly emissive in solution but its emission properties are highly enhanced in the aggregated state due to the restriction of intramolecular rotation (RIR) and large amplitude vibrational modes, demonstrating the phenomenon, aggregation induced emission enhancement (AIEE). It has strong proton capture capability, allowing reversible fluorescence switching in basic and acidic medium and the emission color changes from blue to green in the aggregated state through protonation. It has been explained as a competition between intramolecular charge transfers (ICTs) and the AIEE phenomena at a lower pH range (pH ∼1-4). Such behavior enables it as a fluorescent pH sensor for detection in acidic and basic medium. Morphologies of the particles are characterized using optical and field emission scanning electron microscopic (FESEM) studies. The turn off fluorescence properties of aggregated BPQ have been utilized for the selective detection of picric acid and the fluorescence quenching is explained due to ground state complexation with a strong quenching constant, 7.81 × 10(4) M(-1).
Simulation of K-α Emission from Highly Charged Cu ions for Pinches on ZR
NASA Astrophysics Data System (ADS)
Dasgupta, A.; Giuliani, J. L.; Clark, R. W.; Ouart, N. D.; Jones, B.; Ampleford, D. J.
2012-10-01
Recent spectral data of Cu shots Z1975 and Z2122 from Sandia's ZR machine are believed to show strong K-α emissions. As these K-α lines provide good diagnostics, a detailed spectral model will be developed to investigate these line emissions for analyzing the data. In a Z pinch plasma, K-α emission can occur due to e-beams, hot electrons at the tail of a Maxwellian and also pumping from hot photons emitted near the axis. K-α emission that originates from collisional processes involving hot electrons in the final phase of the pinching plasmas are associated with radiationless electron capture, inner-shell electron collisional excitation and ionization. K-α lines from various ionization stages of various materials such as Fe, Cr, Ni, and Mn were also observed in the ZR data. Contributions from ions with strong K-α transitions will be included for this study which is a preliminary attempt to investigate Cu K-α lines due to hot electrons and photons. Photo-pumped K-α emission from an outer shell is spatially distinguishable from that produced by e-beam on axis.
Hudda, N.; Fruin, S.; Delfino, R. J.; Sioutas, C.
2013-01-01
To evaluate the success of vehicle emissions regulations, trends in both fleet-wide average emissions as well as high-emitter emissions are needed, but it is challenging to capture the full spread of vehicle emission factors (EFs) with chassis dynamometer or tunnel studies, and remote sensing studies cannot evaluate particulate compounds. We developed an alternative method that links real-time on-road pollutant measurements from a mobile platform with real-time traffic data, and allows efficient calculation of both the average and the spread of EFs for light-duty gasoline-powered vehicles (LDG) and heavy-duty diesel-powered vehicles (HDD). This is the first study in California to report EFs under a full range of real-world driving conditions on multiple freeways. Fleet average LDG EFs were in agreement with most recent studies and an order of magnitude lower than observed HDD EFs. HDD EFs reflected the relatively rapid decreases in diesel emissions that have recently occurred in Los Angeles/California, and on I-710, a primary route used for goods movement and a focus of additional truck fleet turnover incentives, HDD EFs were often lower than on other freeways. When freeway emission rates (ER) were quantified as the product of EF and vehicle miles traveled (VMT) per time per mile of freeway, despite a twoto three-fold difference in HDD fractions between freeways, ERs were found to be generally similar in magnitude. Higher LDG VMT on low HDD fraction freeways largely offset the difference. Therefore, the conventional assumption that free ways with the highest HDD fractions are significantly worse sources of total emissions in Los Angeles may no longer be true. PMID:24244208
Hudda, N; Fruin, S; Delfino, R J; Sioutas, C
2013-01-11
To evaluate the success of vehicle emissions regulations, trends in both fleet-wide average emissions as well as high-emitter emissions are needed, but it is challenging to capture the full spread of vehicle emission factors (EFs) with chassis dynamometer or tunnel studies, and remote sensing studies cannot evaluate particulate compounds. We developed an alternative method that links real-time on-road pollutant measurements from a mobile platform with real-time traffic data, and allows efficient calculation of both the average and the spread of EFs for light-duty gasoline-powered vehicles (LDG) and heavy-duty diesel-powered vehicles (HDD). This is the first study in California to report EFs under a full range of real-world driving conditions on multiple freeways. Fleet average LDG EFs were in agreement with most recent studies and an order of magnitude lower than observed HDD EFs. HDD EFs reflected the relatively rapid decreases in diesel emissions that have recently occurred in Los Angeles/California, and on I-710, a primary route used for goods movement and a focus of additional truck fleet turnover incentives, HDD EFs were often lower than on other freeways. When freeway emission rates (ER) were quantified as the product of EF and vehicle miles traveled (VMT) per time per mile of freeway, despite a twoto three-fold difference in HDD fractions between freeways, ERs were found to be generally similar in magnitude. Higher LDG VMT on low HDD fraction freeways largely offset the difference. Therefore, the conventional assumption that free ways with the highest HDD fractions are significantly worse sources of total emissions in Los Angeles may no longer be true.
40 CFR 63.4300 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... which you use the emission rate without add-on controls option, as specified in § 63.4291(a)(2) or (c)(2... with add-on controls option, as specified in § 63.4291(a)(3) or (c)(3), and any web coating/printing... must be in compliance with the operating limits for emission capture systems and add-on control devices...
40 CFR 63.4300 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... which you use the emission rate without add-on controls option, as specified in § 63.4291(a)(2) or (c)(2... with add-on controls option, as specified in § 63.4291(a)(3) or (c)(3), and any web coating/printing... must be in compliance with the operating limits for emission capture systems and add-on control devices...
40 CFR 63.4300 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... which you use the emission rate without add-on controls option, as specified in § 63.4291(a)(2) or (c)(2... with add-on controls option, as specified in § 63.4291(a)(3) or (c)(3), and any web coating/printing... must be in compliance with the operating limits for emission capture systems and add-on control devices...
40 CFR 63.3500 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... compliant material option or the emission rate without add-on controls option, as specified in § 63.3491(a... operation(s) for which you use the emission rate with add-on controls option, as specified in § 63.3491(c... capture systems and add-on control devices required by § 63.3492 at all times, except for those for which...
40 CFR 63.3500 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... compliant material option or the emission rate without add-on controls option, as specified in § 63.3491(a... operation(s) for which you use the emission rate with add-on controls option, as specified in § 63.3491(c... capture systems and add-on control devices required by § 63.3492 at all times, except for those for which...
40 CFR 63.4300 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... which you use the emission rate without add-on controls option, as specified in § 63.4291(a)(2) or (c)(2... with add-on controls option, as specified in § 63.4291(a)(3) or (c)(3), and any web coating/printing... must be in compliance with the operating limits for emission capture systems and add-on control devices...
40 CFR 63.4300 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... which you use the emission rate without add-on controls option, as specified in § 63.4291(a)(2) or (c)(2... with add-on controls option, as specified in § 63.4291(a)(3) or (c)(3), and any web coating/printing... must be in compliance with the operating limits for emission capture systems and add-on control devices...
40 CFR 63.3500 - What are my general requirements for complying with this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... compliant material option or the emission rate without add-on controls option, as specified in § 63.3491(a... operation(s) for which you use the emission rate with add-on controls option, as specified in § 63.3491(c... capture systems and add-on control devices required by § 63.3492 at all times, except for those for which...
40 CFR 63.3965 - How do I determine the emission capture system efficiency?
Code of Federal Regulations, 2013 CFR
2013-07-01
.... (2) Use Method 204A or 204F of appendix M to 40 CFR part 51 to determine the mass fraction of TVH.... TVHi = Mass fraction of TVH in coating, thinner and/or other additive, or cleaning material, i, that is... compares the mass of liquid TVH in materials used in the coating operation to the mass of TVH emissions not...
Methane from the Tropospheric Emission Spectrometer (TES)
NASA Technical Reports Server (NTRS)
Payne, Vivienne; Worden, John; Kulawik, Susan; Frankenberg, Christian; Bowman, Kevin; Wecht, Kevin
2012-01-01
TES V5 CH4 captures latitudinal gradients, regional variability and interannual variation in the free troposphere. V5 joint retrievals offer improved sensitivity to lower troposphere. Time series extends from 2004 to present. V5 reprocessing in progress. Upper tropospheric bias. Mitigated by N2O correction. Appears largely spatially uniform, so can be corrected. How to relate free-tropospheric values to surface emissions.
Mercury (Hg) emissions from coal utilities are difficult to control. Hg eludes capture by most air pollution control devices (APCDs). To determine the gaseous Hg species in stack gases, U.S. EPA Method 5 type sampling is used. In this type of sampling a hole is drilled into th...
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).
Al Sadat, Wajdi I; Archer, Lynden A
2016-07-01
Economical and efficient carbon capture, utilization, and sequestration technologies are a requirement for successful implementation of global action plans to reduce carbon emissions and to mitigate climate change. These technologies are also essential for longer-term use of fossil fuels while reducing the associated carbon footprint. We demonstrate an O2-assisted Al/CO2 electrochemical cell as a new approach to sequester CO2 emissions and, at the same time, to generate substantial amounts of electrical energy. We report on the fundamental principles that guide operations of these cells using multiple intrusive electrochemical and physical analytical methods, including chronopotentiometry, cyclic voltammetry, direct analysis in real-time mass spectrometry, energy-dispersive x-ray spectroscopy, x-ray photoelectron spectroscopy, and coupled thermogravimetric analysis-Fourier transform infrared spectroscopy. On this basis, we demonstrate that an electrochemical cell that uses metallic aluminum as anode and a carbon dioxide/oxygen gas mixture as the active material in the cathode provides a path toward electrochemical generation of a valuable (C2) species and electrical energy. Specifically, we show that the cell first reduces O2 at the cathode to form superoxide intermediates. Chemical reaction of the superoxide with CO2 sequesters the CO2 in the form of aluminum oxalate, Al2(C2O4)3, as the dominant product. On the basis of an analysis of the overall CO2 footprint, which considers emissions associated with the production of the aluminum anode and the CO2 captured/abated by the Al/CO2-O2 electrochemical cell, we conclude that the proposed process offers an important strategy for net reduction of CO2 emissions.
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'.
Al Sadat, Wajdi I.; Archer, Lynden A.
2016-01-01
Economical and efficient carbon capture, utilization, and sequestration technologies are a requirement for successful implementation of global action plans to reduce carbon emissions and to mitigate climate change. These technologies are also essential for longer-term use of fossil fuels while reducing the associated carbon footprint. We demonstrate an O2-assisted Al/CO2 electrochemical cell as a new approach to sequester CO2 emissions and, at the same time, to generate substantial amounts of electrical energy. We report on the fundamental principles that guide operations of these cells using multiple intrusive electrochemical and physical analytical methods, including chronopotentiometry, cyclic voltammetry, direct analysis in real-time mass spectrometry, energy-dispersive x-ray spectroscopy, x-ray photoelectron spectroscopy, and coupled thermogravimetric analysis–Fourier transform infrared spectroscopy. On this basis, we demonstrate that an electrochemical cell that uses metallic aluminum as anode and a carbon dioxide/oxygen gas mixture as the active material in the cathode provides a path toward electrochemical generation of a valuable (C2) species and electrical energy. Specifically, we show that the cell first reduces O2 at the cathode to form superoxide intermediates. Chemical reaction of the superoxide with CO2 sequesters the CO2 in the form of aluminum oxalate, Al2(C2O4)3, as the dominant product. On the basis of an analysis of the overall CO2 footprint, which considers emissions associated with the production of the aluminum anode and the CO2 captured/abated by the Al/CO2-O2 electrochemical cell, we conclude that the proposed process offers an important strategy for net reduction of CO2 emissions. PMID:27453949
What are we missing? Scope 3 greenhouse gas emissions accounting in the metals and minerals industry
NASA Astrophysics Data System (ADS)
Greene, Suzanne E.
2018-05-01
Metal and mineral companies have significant greenhouse gas emissions in their upstream and downstream value chains due to outsourced extraction, beneficiation and transportation activities, depending on a firm's business model. While many companies move towards more transparent reporting of corporate greenhouse gas emissions, value chain emissions remain difficult to capture, particularly in the global supply chain. Incomplete reports make it difficult for companies to track emissions reductions goals or implement sustainable supply chain improvements, especially for commodity products that form the base of many other sector's value chains. Using voluntarily-reported CDP data, this paper sheds light on hotspots in value chain emissions for individual metal and mineral companies, and for the sector as a whole. The state of value chain emissions reporting for the industry is discussed in general, with a focus on where emissions could potentially be underestimated and how estimates could be improved.
Water use at pulverized coal power plants with postcombustion carbon capture and storage.
Zhai, Haibo; Rubin, Edward S; Versteeg, Peter L
2011-03-15
Coal-fired power plants account for nearly 50% of U.S. electricity supply and about a third of U.S. emissions of CO(2), the major greenhouse gas (GHG) associated with global climate change. Thermal power plants also account for 39% of all freshwater withdrawals in the U.S. To reduce GHG emissions from coal-fired plants, postcombustion carbon capture and storage (CCS) systems are receiving considerable attention. Current commercial amine-based capture systems require water for cooling and other operations that add to power plant water requirements. This paper characterizes and quantifies water use at coal-burning power plants with and without CCS and investigates key parameters that influence water consumption. Analytical models are presented to quantify water use for major unit operations. Case study results show that, for power plants with conventional wet cooling towers, approximately 80% of total plant water withdrawals and 86% of plant water consumption is for cooling. The addition of an amine-based CCS system would approximately double the consumptive water use of the plant. Replacing wet towers with air-cooled condensers for dry cooling would reduce plant water use by about 80% (without CCS) to about 40% (with CCS). However, the cooling system capital cost would approximately triple, although costs are highly dependent on site-specific characteristics. The potential for water use reductions with CCS is explored via sensitivity analyses of plant efficiency and other key design parameters that affect water resource management for the electric power industry.
NASA Astrophysics Data System (ADS)
Weinstein, I. A.; Vokhmintsev, A. S.; Chaikin, D. V.; Afonin, Yu. D.
2016-11-01
The high-field electroluminescence (EL) spectra for Al-rich AlN nanowhiskers varying applied voltage were studied. The observed 2.70 eV emission, which can be considered as superposition of two Gaussian bands in 2.75 and 2.53 eV, was analyzed. It was shown that Fowler-Nordheim effect took place in EL mechanism with participation of capturing levels of ON- and VN-centers when AlN nanowhiskers were exposed to an external field of 2.5 ÷ 10 V/μm. Obtained results and made conclusions are in a good agreement with independent electron field emission measurements for different one-dimensional AlN nanostructures.
Rao, Sujaya; Ostroverkhova, Oksana
2015-07-01
Bees have ultraviolet (UV), blue and green photoreceptor types in their compound eyes with which they locate food sources in landscapes that change continuously in cues emanating from plants and backgrounds against which they are perceived. The complexity of bee vision has been elucidated through studies examining individual species under laboratory conditions. Here, we used a bee-attractive fluorescent blue trap as a model for analyzing visual signals in operation outdoors, and across bee species. We manipulated trap color (appearance to humans under light with weak UV component) and UV-induced fluorescence emission, and aligned field capture results with bee vision models. Our studies show that the bees were attracted to traps that under solar illumination exhibited strong fluorescence emission exclusively in the blue spectral region. Through quantitative analysis, we established that strong spectral overlap of trap emittance with the photosensitivity characteristic of the blue receptor type and minimal overlap with those of the other two receptor types is the most critical property of attractive traps. A parameter has been identified which predicts the degree of attractiveness of the traps and which captures trends in the field data across wild bee species and for a diversity of backgrounds.
Ou, Yang; Shi, Wenjing; Smith, Steven J; Ledna, Catherine M; West, J Jason; Nolte, Christopher G; Loughlin, Daniel H
2018-04-15
There are many technological pathways that can lead to reduced carbon dioxide emissions. However, these pathways can have substantially different impacts on other environmental endpoints, such as air quality and energy-related water demand. This study uses an integrated assessment model with state-level resolution of the energy system to compare environmental impacts of alternative low-carbon pathways for the United States. One set of pathways emphasizes nuclear energy and carbon capture and storage, while another set emphasizes renewable energy, including wind, solar, geothermal power, and bioenergy. These are compared with pathways in which all technologies are available. Air pollutant emissions, mortality costs attributable to particulate matter smaller than 2.5 μm in diameter, and energy-related water demands are evaluated for 50% and 80% carbon dioxide reduction targets in 2050. The renewable low-carbon pathways require less water withdrawal and consumption than the nuclear and carbon capture pathways. However, the renewable low-carbon pathways modeled in this study produce higher particulate matter-related mortality costs due to greater use of biomass in residential heating. Environmental co-benefits differ among states because of factors such as existing technology stock, resource availability, and environmental and energy policies.
Not in My Backyard: CCS Sites and Public Perception of CCS.
Braun, Carola
2017-12-01
Carbon capture and storage (CCS) is a technology that counteracts climate change by capturing atmospheric emissions of CO 2 from human activities, storing them in geological formations underground. However, CCS also involves major risks and side effects, and faces strong public opposition. The whereabouts of 408 potential CCS sites in Germany were released in 2011. Using detailed survey data on the public perception of CCS, this study quantifies how living close to a potential storage site affects the acceptance of CCS. It also analyzes the influence of other regional characteristics on the acceptance of CCS. The study finds that respondents who live close to a potential CCS site have significantly lower acceptance rates than those who do not. Living in a coal-mining region also markedly decreases acceptance. © 2017 Society for Risk Analysis.
Analysis of CO2, CO and HC emission reduction in automobiles
NASA Astrophysics Data System (ADS)
Balan, K. N.; Valarmathi, T. N.; Reddy, Mannem Soma Harish; Aravinda Reddy, Gireddy; Sai Srinivas, Jammalamadaka K. M. K.; Vasan
2017-05-01
In the present scenario, the emission from automobiles is becoming a serious problem to the environment. Automobiles, thermal power stations and Industries majorly constitute to the emission of CO2, CO and HC. Though the CO2 available in the atmosphere will be captured by oceans, grasslands; they are not enough to control CO2 present in the atmosphere completely. Also advances in engine and vehicle technology continuously to reduce the emission from engine exhaust are not sufficient to reduce the HC and CO emission. This work concentrates on design, fabrication and analysis to reduce CO2, CO and HC emission from exhaust of automobiles by using molecular sieve 5A of 1.5mm. In this paper, the details of the fabrication, results and discussion about the process are discussed.
Fires Burning near Big Sur, California
2008-06-30
Fires near Big Sur, Calif., continued to burn unchecked when the Advanced Spaceborne Thermal Emission and Reflection Radiometer ASTER instrument on NASA Terra satellite captured this image on Sunday, June 29, 2008.
Jaramillo, Paulina; Griffin, W Michael; Matthews, H Scott
2007-09-01
The U.S. Department of Energy (DOE) estimates that in the coming decades the United States' natural gas (NG) demand for electricity generation will increase. Estimates also suggest that NG supply will increasingly come from imported liquefied natural gas (LNG). Additional supplies of NG could come domestically from the production of synthetic natural gas (SNG) via coal gasification-methanation. The objective of this study is to compare greenhouse gas (GHG), SOx, and NOx life-cycle emissions of electricity generated with NG/LNG/SNG and coal. This life-cycle comparison of air emissions from different fuels can help us better understand the advantages and disadvantages of using coal versus globally sourced NG for electricity generation. Our estimates suggest that with the current fleet of power plants, a mix of domestic NG, LNG, and SNG would have lower GHG emissions than coal. If advanced technologies with carbon capture and sequestration (CCS) are used, however, coal and a mix of domestic NG, LNG, and SNG would have very similar life-cycle GHG emissions. For SOx and NOx we find there are significant emissions in the upstream stages of the NG/ LNG life-cycles, which contribute to a larger range in SOx and NOx emissions for NG/LNG than for coal and SNG.
Permafrost thaw strongly reduces allowable CO2 emissions for 1.5°C and 2°C
NASA Astrophysics Data System (ADS)
Kechiar, M.; Gasser, T.; Kleinen, T.; Ciais, P.; Huang, Y.; Burke, E.; Obersteiner, M.
2017-12-01
We quantify how the inclusion of carbon emission from permafrost thaw impacts the budgets of allowable anthropogenic CO2 emissions. We use the compact Earth system model OSCAR v2.2 which we expand with a permafrost module calibrated to emulate the behavior of the complex models JSBACH, ORCHIDEE and JULES. When using the "exceedance" method and with permafrost thaw turned off, we find budgets very close to the CMIP5 models' estimates reported by IPCC. With permafrost thaw turned on, the total budgets are reduced by 3-4%. This corresponds to a 33-45% reduction of the remaining budget for 1.5°C, and a 9-13% reduction for 2°C. When using the "avoidance" method, however, permafrost thaw reduces the total budget by 3-7%, which corresponds to reductions by 33-56% and 56-79% of the remaining budget for 1.5°C and 2°C, respectively. The avoidance method relies on many scenarios that actually peak below the target whereas the exceedance method overlooks the carbon emitted by thawed permafrost after the temperature target is reached, which explains the difference. If we use only the subset of scenarios in which there is no net negative emissions, the permafrost-induced reduction in total budgets rises to 6-15%. Permafrost thaw therefore makes the emission budgets strongly path-dependent. We also estimate budgets of needed carbon capture in scenarios overshooting the temperature targets. Permafrost thaw strongly increases these capture budgets: in the case of a 1.5°C target overshot by 0.5°C, which is in line with the Paris agreement, about 30% more carbon must be captured. Our conclusions are threefold. First, inclusion of permafrost thaw systematically reduces the emission budgets, and very strongly so if the temperature target is overshot. Second, the exceedance method, that is the only one that complex models can follow, only partially accounts for the effect of slow non-linear processes such as permafrost thaw, leading to overestimated budgets. Third, the newfound strong path-dependency of the budgets renders the concept more delicate to use. For instance, using a budget that implicitly assumes a large development of negative emission technologies may lead to missing the target if these are not as scalable as anticipated.
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
NASA Astrophysics Data System (ADS)
2011-12-01
Research on Global Carbon Emission and Sequestration NSFC Funded Project Made Significant Progress in Quantum Dynamics Functional Human Blood Protein Obtained from Rice How Giant Pandas Thrive on a Bamboo Diet New Evidence of Interpersonal Violence from 129,000 Years Ago Found in China Aptamer-Mediated Efficient Capture and Release of T Lymphocytes on Nanostructured Surfaces BGI Study Results on Resequencing 50 Accessions of Rice Cast New Light on Molecular Breeding BGI Reports Study Results on Frequent Mutation of Genes Encoding UMPP Components in Kidney Cancer Research on Habitat Shift Promoting Species Diversification
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.
Production of twin /Λ-hypernuclei from Ξ- hyperon capture at rest
NASA Astrophysics Data System (ADS)
Ichikawa, A.; Ahn, J. K.; Akikawa, H.; Aoki, S.; Arai, K.; Bahk, S. Y.; Baik, K. M.; Bassalleck, B.; Chung, J. H.; Chung, M. S.; Hoshino, K.; Ieiri, M.; Imai, K.; Iwata, Y. H.; Iwata, Y. S.; Kanda, H.; Kaneko, M.; Kawai, T.; Kim, C. O.; Kim, J. Y.; Kim, S. J.; Kim, S. H.; Kondo, Y.; Kouketsu, T.; Lee, Y. L.; McNabb, J. W. C.; Mitsuhara, M.; Nagase, Y.; Nagoshi, C.; Nakazawa, K.; Noumi, H.; Ogawa, S.; Okabe, H.; Oyama, K.; Park, H. M.; Park, I. G.; Parker, J.; Ra, Y. S.; Rhee, J. T.; Rusek, A.; Shibuya, H.; Sim, K. S.; Saha, P. K.; Seki, D.; Sekimoto, M.; Song, J. S.; Takahashi, H.; Takahashi, T.; Takeutchi, F.; Tanaka, H.; Tanida, K.; Tojo, J.; Torii, H.; Torikai, S.; Ushida, N.; Yamamoto, K.; Yasuda, N.; Yang, J. T.; Yoon, C. J.; Yoon, C. S.; Yosoi, M.; Yoshida, T.; Zhu, L.
2001-02-01
A hybrid emulsion experiment was carried out to study double-strangeness nuclei produced via Ξ- hyperon capture at rest with the expectation of ten times larger statistics than previous experiments. We have analyzed 5% of the total emulsion and found one ``twin-hypernuclei'' event involving the emission of two single-/Λ hypernuclei and a nuclear fragment from a Ξ- hyperon stopping point. The event is interpreted as the decay of a Ξ-+14N atomic system to 5
NASA Astrophysics Data System (ADS)
Ogutu, K. B. Z.; D'Andrea, F.; Ghil, M.; Nyandwi, C.; Manene, M. M.; Muthama, J. N.
2015-04-01
This study uses the global climate-economy-biosphere (CoCEB) model developed in Part 1 to investigate economic aspects of deforestation control and carbon sequestration in forests, as well as the efficiency of carbon capture and storage (CCS) technologies as policy measures for climate change mitigation. We assume - as in Part 1 - that replacement of one technology with another occurs in terms of a logistic law, so that the same law also governs the dynamics of reduction in carbon dioxide emission using CCS technologies. In order to take into account the effect of deforestation control, a slightly more complex description of the carbon cycle than in Part 1 is needed. Consequently, we add a biomass equation into the CoCEB model and analyze the ensuing feedbacks and their effects on per capita gross domestic product (GDP) growth. Integrating biomass into the CoCEB and applying deforestation control as well as CCS technologies has the following results: (i) low investment in CCS contributes to reducing industrial carbon emissions and to increasing GDP, but further investment leads to a smaller reduction in emissions, as well as in the incremental GDP growth; and (ii) enhanced deforestation control contributes to a reduction in both deforestation emissions and in atmospheric carbon dioxide concentration, thus reducing the impacts of climate change and contributing to a slight appreciation of GDP growth. This effect is however very small compared to that of low-carbon technologies or CCS. We also find that the result in (i) is very sensitive to the formulation of CCS costs, while to the contrary, the results for deforestation control are less sensitive.
NASA Astrophysics Data System (ADS)
La Mantia, David; Kumara, Nuwan; Kayani, Asghar; Simon, Anna; Tanis, John
2016-05-01
Total cross sections for single and double capture, as well as the corresponding cross sections for capture resulting in the emission of an Ar K x ray, were measured. This work was performed at Western Michigan University with the use of the tandem Van de Graaff accelerator. A 45 MeV beam of fully-stripped fluorine ions was collided with argon gas molecules in a differentially pumped cell. Surface barrier detectors were used to observe the charge changed projectiles and a Si(Li) x-ray detector, placed at 90o to the incident beam, were used to measure coincidences with Ar K x rays. The total capture cross sections are compared to previously measured cross sections in the existing literature. The coincidence cross sections, considerably smaller than the total cross sections, are found to be nearly equal for single and double capture in contrast to the total cross sections, which vary by about an order of magnitude. Possible reasons for this behavior are discussed. Supported in part by the NSF.
NASA Astrophysics Data System (ADS)
Salari, S.; Ghodsi, F. E.
2018-06-01
A study on the optical properties and photoluminescence (PL) spectra of ternary oxide nanogranular thin films comprising Zr, Zn, and Sn revealed that the change in component ratio could direct the roadmap to improve characteristics of the films. Grazing angle X-ray diffraction analysis showed that incorporation of Sn atoms into the tetragonal structure of Zn/Zr thin film resulted in an amorphous structure. The band gap of film was tunable by precisely controlling the concentration of components. The widening of band gap could correlate to the quantum confinement effect. PL spectra of the composite thin films under excitation at 365 nm showed a sharp red emission with relatively Gaussian line shape, which was intensified in the optimum percentage ratio of 50/30/20. This nearly red emission is attributed to the radiative emission of electrons captured at low-energy traps located near the valence band. An optimum red emission is strongly desirable for use in white LEDs. The comparative study on FTIR spectra of unary, binary, and ternary thin films confirmed successful composition of three different metal oxides in ternary thin films. Detailed investigation on FTIR spectra of ternary compounds revealed that the quenching in PL emission at higher percentage of Sn was originally due to the hydroxyl group.
Capture and decay of electroweak WIMPonium
NASA Astrophysics Data System (ADS)
Asadi, Pouya; Baumgart, Matthew; Fitzpatrick, Patrick J.; Krupczak, Emmett; Slatyer, Tracy R.
2017-02-01
The spectrum of Weakly-Interacting-Massive-Particle (WIMP) dark matter generically possesses bound states when the WIMP mass becomes sufficiently large relative to the mass of the electroweak gauge bosons. The presence of these bound states enhances the annihilation rate via resonances in the Sommerfeld enhancement, but they can also be produced directly with the emission of a low-energy photon. In this work we compute the rate for SU(2) triplet dark matter (the wino) to bind into WIMPonium—which is possible via single-photon emission for wino masses above 5 TeV for relative velocity v < O(10-2) —and study the subsequent decays of these bound states. We present results with applications beyond the wino case, e.g. for dark matter inhabiting a nonabelian dark sector; these include analytic capture and transition rates for general dark sectors in the limit of vanishing force carrier mass, efficient numerical routines for calculating positive and negative-energy eigenstates of a Hamiltonian containing interactions with both massive and massless force carriers, and a study of the scaling of bound state formation in the short-range Hulth&apos{e}n potential. In the specific case of the wino, we find that the rate for bound state formation is suppressed relative to direct annihilation, and so provides only a small correction to the overall annihilation rate. The soft photons radiated by the capture process and by bound state transitions could permit measurement of the dark matter's quantum numbers; for wino-like dark matter, such photons are rare, but might be observable by a future ground-based gamma-ray telescope combining large effective area and a low energy threshold.
Pan, Wenxiao; Qi, Yuanyuan; Wang, Ruoxi; Han, Zhe; Zhang, Dongju; Zhan, Jinhua
2013-04-01
The effective abatement of flue gas emissions, especially polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), is one of the challenging issues in the field of environmental science currently. Imidazolium-based dicyanamide ionic liquids (ILs) were proposed to have potential in controlling the emissions of PCDD/Fs. However, the relevant mechanism at the molecular level still remains unclear. To address this subject, we here present a combined molecular dynamics (MD) simulation and quantum chemical (QM) study on the adsorption of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most toxic congener among PCDD/F family, by 1-butyl-3-methylimidazolium dicyanamide IL, a representative imidazolium dicyanoamide ILs, which were demonstrated to possess high capture capability for PCDD/Fs. The MD simulation results show that TCDD molecules can be effectively adsorbed on the IL surface to form a dense layer, but cannot enter the interior of the IL. The results of QM calculations show that the adsorption of TCDDs on the IL surface occurs via intra-molecular hydrogen bond interactions. The calculated interaction energy of the anion with TCDD molecule is two times more than that of the cation, implying that the IL anion dominates the interaction with TCDD molecules, while the cation plays a secondary role. Based on the calculated results, we propose that imidazolium dicyanamide IL films/membranes may be better materials than the corresponding bulk for capturing TCDD. The present theoretical results may be helpful to designing the functional ILs which effectively capture and concentrate PCDD/F compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.
The impact of oil burning on kraft recovery furnace SO sub 2 emissions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Someshwar, A.V.; Pinkerton, J.E.; Caron, A.L.
1991-04-01
Auxiliary fossil fuel, either natural gas or fuel oil, is burned in kraft recovery furnaces during furnace startups and shutdowns, furnace upsets, and periods of substantially reduced rates of black liquor firing. The efficiency of sulfur capture and retention during normal operation of a kraft recovery furnace is inherently high. Consequently, not all the SO{sub 2} from occasional burning of sulfur-containing fuel oil in the furnace would be expected to end up in the stack gases. However, the extent to which such SO{sub 2} is captured by the alkali fume generation processes has not been well documented. In this paper,more » the authors examines the impact that burning oil in kraft recovery furnaces has on the SO{sub 2} emissions. The work included analyses of long-term SO{sub 2} data from a continuous emission monitoring system (CEMS) obtained for four furnaces that burned medium sulfur fuel oil as auxiliary fuel. It also included tests conducted on four furnaces in which varying amounts of oil were co-fired with black liquor.« less
NASA Astrophysics Data System (ADS)
Zavala, Miguel; Molina, Luisa T.; Maiz, Pablo; Monsivais, Israel; Chow, Judith C.; Watson, John G.; Munguia, Jose Luis; Cardenas, Beatriz; Fortner, Edward C.; Herndon, Scott C.; Roscioli, Joseph R.; Kolb, Charles E.; Knighton, Walter B.
2018-04-01
In many parts of the developing world and economies in transition, small-scale traditional brick kilns are a notorious source of urban air pollution. Many are both energy inefficient and burn highly polluting fuels that emit significant levels of black carbon (BC), organic carbon (OC) and other atmospheric pollutants into local communities, resulting in severe health and environmental impacts. However, only a very limited number of studies are available on the emission characteristics of brick kilns; thus, there is a need to characterize their gaseous and particulate matter (PM) emission factors to better assess their overall contribution to emissions inventories and to quantify their ecological, human health, and climate impacts. In this study, the fuel-, energy-, and brick-based emissions factors and time-based emission ratios of BC, OC, inorganic PM components, CO, SO2, CH4, NOx, and selected volatile organic compounds (VOCs) from three artisanal brick kilns with different designs in Mexico were quantified using the tracer ratio sampling technique. Simultaneous measurements of PM components, CO, and CO2 were also obtained using a sampling probe technique. Additional measurements included the internal temperature of the brick kilns, mechanical resistance of bricks produced, and characteristics of fuels employed. Average fuel-based BC emission factors ranged from 0.15 to 0.58 g (kg fuel)-1, whereas BC/OC mass ratios ranged from 0.9 to 5.2, depending on the kiln type. The results show that both techniques capture similar temporal profiles of the brick kiln emissions and produce comparable emission factors. A more integrated inter-comparison of the brick kilns' performances was obtained by simultaneously assessing emissions factors, energy efficiency, fuel consumption, and the quality of the bricks produced.
Questioning the accuracy of greenhouse gas accounting from agricultural waste: a case study.
Chung, Matthew L; Shilton, Andrew N; Guieysse, Benoit; Pratt, Chris
2013-01-01
The New Zealand Greenhouse Gas Inventory (the NZ Inventory) uses country-specific data to quantify CH emissions from anaerobic ponds treating dairy farm effluent (315 Gg CO equivalent [CO-e] in 2009). In this study, we used literature data to: (i) evaluate the accuracy of the NZ Inventory's parameters used to quantify these CH emissions; and (ii) determine whether the NZ Inventory's scope is capturing the full spectrum of sources with bio-CH potential entering anaerobic ponds. The research indicated that the current NZ Inventory methodology is underestimating CH emissions from anaerobic ponds across New Zealand by 264 to 603 Gg CO-e annually. Moreover, the NZ Inventory is currently not accounting for (i) manure from supplementary feed pads and stand-off pads (annual CH emissions = 207-330 Gg CO-e); (ii) waste milk (153-280 Gg CO-e); and (iii) supplementary feed waste (90-216 Gg CO-e). Annual CH emissions from anaerobic ponds on dairy farms across New Zealand are thus more likely to be 1029 to 1744 Gg CO-e, indicating that the NZ Inventory is reporting as little as 18% of actual CH emissions produced by this sector. These additional wastes are not accounted for in the methodology prescribed by the Intergovernmental Panel on Climate Change for estimating CH emissions from dairy manure. Consequently, other significant dairying nations will also probably be underestimating their waste CH emissions. Our research highlights that, if governments attempt to include country-specific emission factors in their greenhouse gas inventories, these factors must be based on an assessment of the full spectrum of sources contributing to greenhouse gas emissions within any given sector. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Study of nitro-polycyclic aromatic hydrocarbons in fine and coarse atmospheric particles
NASA Astrophysics Data System (ADS)
Teixeira, Elba Calesso; Garcia, Karine Oliveira; Meincke, Larissa; Leal, Karen Alam
2011-08-01
The purpose of the present study was to evaluate six nitro-polycyclic aromatic hydrocarbons (NPAHs) in fine (< 2.5 μm) and coarse (2.5-10 μm) atmospheric particles in an urban and industrial area located in the Metropolitan Area of Porto Alegre (MAPA), RS, Brazil. The method used was of NPAHs isolation and derivatization, and subsequent gas chromatography by electron capture detection (CG/ECD). Results revealed a higher concentration of NPAHs, especially 3-nitrofluoranthene and 1-nitropyrene, in fine particles in the sampling sites studied within the MAPA. The diagnostic ratios calculated for PAHs and NPAHs identified the influence of heavy traffic, mainly of diesel emissions. The correlation of NPAHs with other pollutants (NO x, NO 2, NO and O 3) evidence the influence of vehicular emissions in the MAPA. The seasonal variation evidenced higher NPAHs concentrations in the fine particles during winter for most compounds studied.
Integrated Assessment of Carbon Dioxide Removal
NASA Astrophysics Data System (ADS)
Rickels, W.; Reith, F.; Keller, D.; Oschlies, A.; Quaas, M. F.
2018-03-01
To maintain the chance of keeping the average global temperature increase below 2°C and to limit long-term climate change, removing carbon dioxide from the atmosphere (carbon dioxide removal, CDR) is becoming increasingly necessary. We analyze optimal and cost-effective climate policies in the dynamic integrated assessment model (IAM) of climate and the economy (DICE2016R) and investigate (1) the utilization of (ocean) CDR under different climate objectives, (2) the sensitivity of policies with respect to carbon cycle feedbacks, and (3) how well carbon cycle feedbacks are captured in the carbon cycle models used in state-of-the-art IAMs. Overall, the carbon cycle model in DICE2016R shows clear improvements compared to its predecessor, DICE2013R, capturing much better long-term dynamics and also oceanic carbon outgassing due to excess oceanic storage of carbon from CDR. However, this comes at the cost of a (too) tight short-term remaining emission budget, limiting the model suitability to analyze low-emission scenarios accurately. With DICE2016R, the compliance with the 2°C goal is no longer feasible without negative emissions via CDR. Overall, the optimal amount of CDR has to take into account (1) the emission substitution effect and (2) compensation for carbon cycle feedbacks.
Hydropower's Biogenic Carbon Footprint
Pfister, Stephan
2016-01-01
Global warming is accelerating and the world urgently needs a shift to clean and renewable energy. Hydropower is currently the largest renewable source of electricity, but its contribution to climate change mitigation is not yet fully understood. Hydroelectric reservoirs are a source of biogenic greenhouse gases and in individual cases can reach the same emission rates as thermal power plants. Little is known about the severity of their emissions at the global scale. Here we show that the carbon footprint of hydropower is far higher than previously assumed, with a global average of 173 kg CO2 and 2.95 kg CH4 emitted per MWh of electricity produced. This results in a combined average carbon footprint of 273 kg CO2e/MWh when using the global warming potential over a time horizon of 100 years (GWP100). Nonetheless, this is still below that of fossil energy sources without the use of carbon capture and sequestration technologies. We identified the dams most promising for capturing methane for use as alternative energy source. The spread among the ~1500 hydropower plants analysed in this study is large and highlights the importance of case-by-case examinations. PMID:27626943
Visible camera imaging of plasmas in Proto-MPEX
NASA Astrophysics Data System (ADS)
Mosby, R.; Skeen, C.; Biewer, T. M.; Renfro, R.; Ray, H.; Shaw, G. C.
2015-11-01
The prototype Material Plasma Exposure eXperiment (Proto-MPEX) is a linear plasma device being developed at Oak Ridge National Laboratory (ORNL). This machine plans to study plasma-material interaction (PMI) physics relevant to future fusion reactors. Measurements of plasma light emission will be made on Proto-MPEX using fast, visible framing cameras. The cameras utilize a global shutter, which allows a full frame image of the plasma to be captured and compared at multiple times during the plasma discharge. Typical exposure times are ~10-100 microseconds. The cameras are capable of capturing images at up to 18,000 frames per second (fps). However, the frame rate is strongly dependent on the size of the ``region of interest'' that is sampled. The maximum ROI corresponds to the full detector area, of ~1000x1000 pixels. The cameras have an internal gain, which controls the sensitivity of the 10-bit detector. The detector includes a Bayer filter, for ``true-color'' imaging of the plasma emission. This presentation will exmine the optimized camera settings for use on Proto-MPEX. This work was supported by the US. D.O.E. contract DE-AC05-00OR22725.
Tidal variability in methane and nitrous oxide emissions along a subtropical estuarine gradient
NASA Astrophysics Data System (ADS)
Sturm, Katrin; Werner, Ursula; Grinham, Alistair; Yuan, Zhiguo
2017-06-01
This study investigates the tidal variability in methane (CH4) and nitrous oxide (N2O) emissions along a gradient of the subtropical Brisbane River estuary. Sampling was conducted at the upper, middle and lower reaches over two tidal cycles in 2013 and 2014. Methane and N2O emissions varied significantly over tidal cycles at all sites. Methane and N2O emissions measured at all locations and in both campaigns varied substantially in time, with the maximum to minimum flux ratio in a cycle varying between 2.5 - 9 and 1.7-4.7 times, respectively. Methane emissions peaked just before or at slack tides. In comparison, no clear patterns were observed between the N2O emissions and the tidal cycle despite there being large variations in N2O emissions in some cases. Methane concentrations were elevated during low tides whereas N2O concentrations showed no clear pattern over the tidal cycle. Surface water concentrations and tidal currents played important roles in CH4 and N2O emissions, but wind did not. Our findings show that measurements at a single point in time and site would result in significant errors in CH4 and N2O emission estimates. An adequate and careful sampling scheme is required to capture spatial and temporal variations of CH4 and N2O emissions and surface water concentrations which should cover at least one tidal cycle in different estuarine sections.
NASA Astrophysics Data System (ADS)
Mues, Andrea; Lauer, Axel; Lupascu, Aurelia; Rupakheti, Maheswar; Kuik, Friderike; Lawrence, Mark G.
2018-06-01
An evaluation of the meteorology simulated using the Weather Research and Forecast (WRF) model for the region of south Asia and Nepal with a focus on the Kathmandu Valley is presented. A particular focus of the model evaluation is placed on meteorological parameters that are highly relevant to air quality such as wind speed and direction, boundary layer height and precipitation. The same model setup is then used for simulations with WRF including chemistry and aerosols (WRF-Chem). A WRF-Chem simulation has been performed using the state-of-the-art emission database, EDGAR HTAP v2.2, which is the Emission Database for Global Atmospheric Research of the Joint Research Centre (JRC) of the European Commission, in cooperation with the Task Force on Hemispheric Transport of Air Pollution (TF HTAP) organized by the United Nations Economic Commission for Europe, along with a sensitivity simulation using observation-based black carbon emission fluxes for the Kathmandu Valley. The WRF-Chem simulations are analyzed in comparison to black carbon measurements in the valley and to each other. The evaluation of the WRF simulation with a horizontal resolution of 3×3 km2 shows that the model is often able to capture important meteorological parameters inside the Kathmandu Valley and the results for most meteorological parameters are well within the range of biases found in other WRF studies especially in mountain areas. But the evaluation results also clearly highlight the difficulties of capturing meteorological parameters in such complex terrain and reproducing subgrid-scale processes with a horizontal resolution of 3×3 km2. The measured black carbon concentrations are typically systematically and strongly underestimated by WRF-Chem. A sensitivity study with improved emissions in the Kathmandu Valley shows significantly reduced biases but also underlines several limitations of such corrections. Further improvements of the model and of the emission data are needed before being able to use the model to robustly assess air pollution mitigation scenarios in the Kathmandu region.
NASA Astrophysics Data System (ADS)
Colette, A.; Ciarelli, G.; Otero, N.; Theobald, M.; Solberg, S.; Andersson, C.; Couvidat, F.; Manders-Groot, A.; Mar, K. A.; Mircea, M.; Pay, M. T.; Raffort, V.; Tsyro, S.; Cuvelier, K.; Adani, M.; Bessagnet, B.; Bergstrom, R.; Briganti, G.; Cappelletti, A.; D'isidoro, M.; Fagerli, H.; Ojha, N.; Roustan, Y.; Vivanco, M. G.
2017-12-01
The Eurodelta-Trends multi-model chemistry-transport experiment has been designed to better understand the evolution of air pollution and its drivers for the period 1990-2010 in Europe. The main objective of the experiment is to assess the efficiency of air pollutant emissions mitigation measures in improving regional scale air quality. The experiment is designed in three tiers with increasing degree of computational demand in order to facilitate the participation of as many modelling teams as possible. The basic experiment consists of simulations for the years 1990, 2000 and 2010. Sensitivity analysis for the same three years using various combinations of (i) anthropogenic emissions, (ii) chemical boundary conditions and (iii) meteorology complements it. The most demanding tier consists in two complete time series from 1990 to 2010, simulated using either time varying emissions for corresponding years or constant emissions. Eight chemistry-transport models have contributed with calculation results to at least one experiment tier, and six models have completed the 21-year trend simulations. The modelling results are publicly available for further use by the scientific community. We assess the skill of the models in capturing observed air pollution trends for the 1990-2010 time period. The average particulate matter relative trends are well captured by the models, even if they display the usual lower bias in reproducing absolute levels. Ozone trends are also well reproduced, yet slightly overestimated in the 1990s. The attribution study emphasizes the efficiency of mitigation measures in reducing air pollution over Europe, although a strong impact of long range transport is pointed out for ozone trends. Meteorological variability is also an important factor in some regions of Europe. The results of the first health and ecosystem impact studies impacts building upon a regional scale multi-model ensemble over a 20yr time period will also be presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Easley, Emily A.
Authored article from the media services team talking about Dave Heldebrant's research with CO2 capture with reversible ionic liquids. The article also provides a look into Dave's personal life and why he became a scientist.
40 CFR 63.7765 - What definitions apply to this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... means the collection of components used to capture gases and fumes released from one or more emissions... of this subpart, the sum of the concentrations of antimony, arsenic, beryllium, cadmium, chromium...
40 CFR 63.7765 - What definitions apply to this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... means the collection of components used to capture gases and fumes released from one or more emissions... of this subpart, the sum of the concentrations of antimony, arsenic, beryllium, cadmium, chromium...
40 CFR 63.7765 - What definitions apply to this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... means the collection of components used to capture gases and fumes released from one or more emissions... of this subpart, the sum of the concentrations of antimony, arsenic, beryllium, cadmium, chromium...
40 CFR 63.7765 - What definitions apply to this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... means the collection of components used to capture gases and fumes released from one or more emissions... of this subpart, the sum of the concentrations of antimony, arsenic, beryllium, cadmium, chromium...
Boron analysis for neutron capture therapy using particle-induced gamma-ray emission.
Nakai, Kei; Yamamoto, Yohei; Okamoto, Emiko; Yamamoto, Tetsuya; Yoshida, Fumiyo; Matsumura, Akira; Yamada, Naoto; Kitamura, Akane; Koka, Masashi; Satoh, Takahiro
2015-12-01
The neutron source of BNCT is currently changing from reactor to accelerator, but peripheral facilities such as a dose-planning system and blood boron analysis have still not been established. To evaluate the potential application of particle-induced gamma-ray emission (PIGE) for boron measurement in clinical boron neutron capture therapy, boronophenylalanine dissolved within a cell culture medium was measured using PIGE. PIGE detected 18 μgB/mL f-BPA in the culture medium, and all measurements of any given sample were taken within 20 min. Two hours of f-BPA exposure was required to create a boron distribution image. However, even though boron remained in the cells, the boron on the cell membrane could not be distinguished from the boron in the cytoplasm. Copyright © 2015 Elsevier Ltd. All rights reserved.
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.
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).
Subtask 2.18 - Advancing CO 2 Capture Technology: Partnership for CO 2 Capture (PCO 2C) Phase III
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kay, John; Azenkeng, Alexander; Fiala, Nathan
2016-03-31
Industries and utilities continue to investigate ways to decrease their carbon footprint. Carbon capture and storage (CCS) can enable existing power generation facilities to meet the current national CO 2 reduction goals. The Partnership for CO2 Capture Phase III focused on several important research areas in an effort to find ways to decrease the cost of capture across both precombustion and postcombustion platforms. Two flue gas pretreatment technologies for postcombustion capture, an SO 2 reduction scrubbing technology from Cansolv Technologies Inc. and the Tri-Mer filtration technology that combines particulate, NOx, and SO 2 control, were evaluated on the Energy &more » Environmental Research Center’s (EERC’s) pilot-scale test system. Pretreating the flue gas should enable more efficient, and therefore less expensive, CO 2 capture. Both technologies were found to be effective in pretreating flue gas prior to CO 2 capture. Two new postcombustion capture solvents were tested, one from the Korea Carbon Capture and Sequestration R&D Center (KCRC) and one from CO 2 Solutions Incorporated. Both of these solvents showed the ability to capture CO 2 while requiring less regeneration energy, which would reduce the cost of capture. Hydrogen separation membranes from Commonwealth Scientific and Industrial Research Organisation were evaluated through precombustion testing. They are composed of vanadium alloy, which is less expensive than the palladium alloys that are typically used. Their performance was comparable to that of other membranes that have been tested at the EERC. Aspen Plus® software was used to model the KCRC and CO 2 Solutions solvents and found that they would result in significantly improved overall plant performance. The modeling effort also showed that the parasitic steam load at partial capture of 45% is less than half that of 90% overall capture, indicating savings that could be accrued if 90% capture is not required. Modeling of three regional power plants using the Carnegie Mellon Integrated Environmental Control Model showed that, among other things, the use of a bypass during partial capture may minimize the size of the capture tower(s) and result in a slight reduction in the revenue required to operate the capture facility. The results reinforced that a one-size-fits-all approach cannot be taken to adding capture to a power plant. Laboratory testing indicated that Fourier transform infrared spectroscopy could be used to continuously sample stack emissions at CO 2 capture facilities to detect and quantify any residual amine or its degradation products, particularly nitrosamines. The information gathered during Phase III is important for utility stakeholders as they determine how to reduce their CO 2 emissions in a carbon-constrained world. This subtask was funded through the EERC–U.S. Department of Energy (DOE) Joint Program on Research and Development for Fossil Energy-Related Resources Cooperative Agreement No. DE-FC26-08NT43291. Nonfederal funding was provided by the North Dakota Industrial Commission, PPL Montana, Nebraska Public Power District, Tri-Mer Corporation, Montana–Dakota Utilities Co., Basin Electric Power Cooperative, KCRC/Korean Institute of Energy Research, Cansolv Technologies, and CO 2 Solutions, Inc.« less
Mercury speciation and emissions from coal combustion in Guiyang, Southwest China.
Tang, Shunlin; Feng, Xinbin; Qiu, Jianrong; Yin, Guoxun; Yang, Zaichan
2007-10-01
Although China has been regarded as one of the largest anthropogenic mercury emission source with coal combustion, so far the actual measurements of Hg species and Hg emissions from the combustion and the capture of Hg in Chinese emission control devices were very limited. Aiming at Hg mercury species measurements in Guiyang, the capital city of Guizhou province in Southwest China, we studied flue gases of medium-to-small-sized industrial steam coal-firing boiler (10-30 t/h) with no control devices, medium-to-small-sized industrial steam coal-firing boiler with WFGD and large-scale coal combustion with ESPs using Ontario Hytro method. We obtained mercury emission factors of the three representative coal combustion and estimated mercury emissions in Guiyang in 2003, as well as the whole province from 1986 to 2002. Coal combustion in Guiyang emitted 1898 kg mercury to the atmosphere, of which 36% Hg is released from power plants, 41% from industrial coal combustion, and 23% from domestic users, and 267 kg is Hg(p), 813 kg is Hg(2+) and 817 kg is Hg0. Mercury emission in Guizhou province increased sharply from 5.8 t in 1986 to 16.4 t in 2002. With the implementation of national economic strategy of China's Western Development, the annual mercury emission from coal combustion in the province is estimated to be about 32 t in 2015.
Reversible capture of SO2 through functionalized ionic liquids.
Yang, Dezhong; Hou, Minqiang; Ning, Hui; Ma, Jun; Kang, Xinchen; Zhang, Jianling; Han, Buxing
2013-07-01
Emission of SO2 in flue gas from the combustion of fossil fuels leads to severe environmental problems. Exploration of green and efficient methods to capture SO2 is an interesting topic, especially at lower SO2 partial pressures. In this work, ionic liquids (ILs) 1-(2-diethylaminoethyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Et2 NEMim][Tf2 N]) and 1-(2-diethylaminoethyl)-3-methylimidazolium tetrazolate ([Et2 NEMim][Tetz]) were synthesized. The performances of the two ILs to capture SO2 were studied under different conditions. It was demonstrated that the ILs were very efficient for SO2 absorption. The [Et2 NEMim][Tetz] IL designed in this work could absorb 0.47 g(SO2)g(IL)(-1) at 0.0101 MPa SO2 partial pressure, which is the highest capacity reported to date under the same conditions. The main reason for the large capacity was that both the cation and the anion could capture SO2 chemically. In addition, the IL could easily be regenerated, and the very high absorption capacity and rapid absorption/desorption rates were not changed over five repeated cycles. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Evaluating policy-relevant emission inventories for transportation and electricity (Invited)
NASA Astrophysics Data System (ADS)
Holloway, T.; Meier, P.; Bickford, E. E.
2013-12-01
We explore the challenges and opportunities in evaluating bottom-up emission inventories for transportation and electricity. These anthropogenic emissions respond in complex ways to technology and activity changes. Thus, it is essential that inventories capture historic emissions consistent with observations, as well as future emissions consistent with policy scenarios. For transportation, we focus on freight-related trucking emissions, represented by the Wisconsin Inventory for Freight Emissions (WIFE), developed with activity data from the U.S. Federal Highway Administration Freight Analysis Framework and emission factors from the EPA MOVES model. Because WIFE is linked to commodity flows and roadway speeds, it offers a useful data set to evaluate policy changes such as truck-to-rail modal shifts and alternative fuel choices. However, the value of the inventory in assessing these scenarios depends on its skill in calculating frieght-related emissions. Satellite data of nitrogen dioxide (NO2) from the OMI instrument aboard the NASA Aura satellite is used to evaluate truck and rail NOx emissions, especially on rural highways away from ground-based monitors. For electricity, we use the MyPower electricity dispatch model to calculate emissions and power generation in response to policy and technology changes. These include renewable portfolio standards, conservation, increased natural gas, and response to building demand. To evaluate MyPower, we compare with the Clean Air Markets database, and 2007 calculated daily afternoon emissions with satellite-derived NO2 from OMI. Drawing on the results of these studies, we discuss strategies to meet the information demands of both historically correct air quality inputs and future-relevant policy scenarios.
Chuen, Onn Chiu; Yusoff, Sumiani
2012-03-01
This study performed an assessment on the beneficial of the Clean Development Mechanism (CDM) application on waste treatment system in a local palm oil industry in Malaysia. Life cycle assessment (LCA) was conducted to assess the environmental impacts of the greenhouse gas (GHG) reduction from the CDM application. Calculations on the emission reduction used the methodology based on AM002 (Avoided Wastewater and On-site Energy Use Emissions in the Industrial Sector) Version 4 published by United Nations Framework Convention on Climate Change (UNFCC). The results from the studies showed that the introduction of CDM in the palm oil mill through conversion of the captured biogas from palm oil mill effluent (POME) treatment into power generation were able to reduce approximate 0.12 tonnes CO2 equivalent concentration (tCO2e) emission and 30 kW x hr power generation per 1 tonne of fresh fruit bunch processed. Thus, the application of CDM methodology on palm oil mill wastewater treatment was able to reduce up to 1/4 of the overall environment impact generated in palm oil mill.
In situ studies of materials for high temperature CO2 capture and storage.
Dunstan, Matthew T; Maugeri, Serena A; Liu, Wen; Tucker, Matthew G; Taiwo, Oluwadamilola O; Gonzalez, Belen; Allan, Phoebe K; Gaultois, Michael W; Shearing, Paul R; Keen, David A; Phillips, Anthony E; Dove, Martin T; Scott, Stuart A; Dennis, John S; Grey, Clare P
2016-10-20
Carbon capture and storage (CCS) offers a possible solution to curb the CO 2 emissions from stationary sources in the coming decades, considering the delays in shifting energy generation to carbon neutral sources such as wind, solar and biomass. The most mature technology for post-combustion capture uses a liquid sorbent, amine scrubbing. However, with the existing technology, a large amount of heat is required for the regeneration of the liquid sorbent, which introduces a substantial energy penalty. The use of alternative sorbents for CO 2 capture, such as the CaO-CaCO 3 system, has been investigated extensively in recent years. However there are significant problems associated with the use of CaO based sorbents, the most challenging one being the deactivation of the sorbent material. When sorbents such as natural limestone are used, the capture capacity of the solid sorbent can fall by as much as 90 mol% after the first 20 carbonation-regeneration cycles. In this study a variety of techniques were employed to understand better the cause of this deterioration from both a structural and morphological standpoint. X-ray and neutron PDF studies were employed to understand better the local surface and interfacial structures formed upon reaction, finding that after carbonation the surface roughness is decreased for CaO. In situ synchrotron X-ray diffraction studies showed that carbonation with added steam leads to a faster and more complete conversion of CaO than under conditions without steam, as evidenced by the phases seen at different depths within the sample. Finally, in situ X-ray tomography experiments were employed to track the morphological changes in the sorbents during carbonation, observing directly the reduction in porosity and increase in tortuosity of the pore network over multiple calcination reactions.
NASA Astrophysics Data System (ADS)
Stohl, A.; Klimont, Z.; Eckhardt, S.; Kupiainen, K.
2013-04-01
Arctic Haze is a seasonal phenomenon with high concentrations of accumulation-mode aerosols occurring in the Arctic in winter and early spring. Chemistry transport models and climate chemistry models struggle to reproduce this phenomenon, and this has recently prompted changes in aerosol removal schemes to remedy the modeling problems. In this paper, we show that shortcomings in current emission data sets are at least as important. We perform a 3 yr model simulation of black carbon (BC) with the Lagrangian particle dispersion model FLEXPART. The model is driven with a new emission data set which includes emissions from gas flaring. While gas flaring is estimated to contribute less than 3% of global BC emissions in this data set, flaring dominates the estimated BC emissions in the Arctic (north of 66° N). Putting these emissions into our model, we find that flaring contributes 42% to the annual mean BC surface concentrations in the Arctic. In March, flaring even accounts for 52% of all Arctic BC near the surface. Most of the flaring BC remains close to the surface in the Arctic, so that the flaring contribution to BC in the middle and upper troposphere is small. Another important factor determining simulated BC concentrations is the seasonal variation of BC emissions from domestic combustion. We have calculated daily domestic combustion emissions using the heating degree day (HDD) concept based on ambient air temperature and compare results from model simulations using emissions with daily, monthly and annual time resolution. In January, the Arctic-mean surface concentrations of BC due to domestic combustion emissions are 150% higher when using daily emissions than when using annually constant emissions. While there are concentration reductions in summer, they are smaller than the winter increases, leading to a systematic increase of annual mean Arctic BC surface concentrations due to domestic combustion by 68% when using daily emissions. A large part (93%) of this systematic increase can be captured also when using monthly emissions; the increase is compensated by a decreased BC burden at lower latitudes. In a comparison with BC measurements at six Arctic stations, we find that using daily-varying domestic combustion emissions and introducing gas flaring emissions leads to large improvements of the simulated Arctic BC, both in terms of mean concentration levels and simulated seasonality. Case studies based on BC and carbon monoxide (CO) measurements from the Zeppelin observatory appear to confirm flaring as an important BC source that can produce pollution plumes in the Arctic with a high BC/CO enhancement ratio, as expected for this source type. Our results suggest that it may not be "vertical transport that is too strong or scavenging rates that are too low" and "opposite biases in these processes" in the Arctic and elsewhere in current aerosol models, as suggested in a recent review article (Bond et al., 2013), but missing emission sources and lacking time resolution of the emission data that are causing opposite model biases in simulated BC concentrations in the Arctic and in the mid-latitudes.
NASA Astrophysics Data System (ADS)
Kam, Winnie; Liacos, James W.; Schauer, James J.; Delfino, Ralph J.; Sioutas, Constantinos
2012-12-01
An on-road sampling campaign was conducted on two major surface streets (Wilshire and Sunset Boulevards) in Los Angeles, CA, to characterize PM components including metals, trace elements, and organic species for three PM size fractions (PM10-2.5, PM2.5-0.25, and PM0.25). Fuel-based emission factors (mass of pollutant per kg of fuel) were calculated to assess the emissions profile of a light-duty vehicle (LDV) traffic fleet characterized by stop-and-go driving conditions that are reflective of urban street driving. Emission factors for metals and trace elements were highest in PM10-2.5 while emission factors for PAHs and hopanes and steranes were highest in PM0.25. PM2.5 emission factors were also compared to previous freeway, roadway tunnel, and dynamometer studies based on an LDV fleet to determine how various environments and driving conditions may influence concentrations of PM components. The on-road sampling methodology deployed in the current study captured substantially higher levels of metals and trace elements associated with vehicular abrasion (Fe, Ca, Cu, and Ba) and crustal origins (Mg and Al) than previous LDV studies. The semi-volatile nature of PAHs resulted in higher levels of PAHs in the particulate phase for LDV tunnel studies (Phuleria et al., 2006) and lower levels of PAHs in the particulate phase for freeway studies (Ning et al., 2008). With the exception of a few high molecular weight PAHs, the current study's emission factors were in between the LDV tunnel and LDV freeway studies. In contrast, hopane and sterane emission factors were generally comparable between the current study, the LDV tunnel, and LDV freeway, as expected given the greater atmospheric stability of these organic compounds. Overall, the emission factors from the dynamometer studies for metals, trace elements, and organic species are lower than the current study. Lastly, n-alkanes (C19-C40) were quantified and alkane carbon preference indices (CPIs) were determined to be in the range of 1-2, indicating substantial anthropogenic source contribution for surface streets in Los Angeles.
Life-cycle analysis of greenhouse gas emissions from renewable jet fuel production.
de Jong, Sierk; Antonissen, Kay; Hoefnagels, Ric; Lonza, Laura; Wang, Michael; Faaij, André; Junginger, Martin
2017-01-01
The introduction of renewable jet fuel (RJF) is considered an important emission mitigation measure for the aviation industry. This study compares the well-to-wake (WtWa) greenhouse gas (GHG) emission performance of multiple RJF conversion pathways and explores the impact of different co-product allocation methods. The insights obtained in this study are of particular importance if RJF is included as an emission mitigation instrument in the global Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA). Fischer-Tropsch pathways yield the highest GHG emission reduction compared to fossil jet fuel (86-104%) of the pathways in scope, followed by Hydrothermal Liquefaction (77-80%) and sugarcane- (71-75%) and corn stover-based Alcohol-to-Jet (60-75%). Feedstock cultivation, hydrogen and conversion inputs were shown to be major contributors to the overall WtWa GHG emission performance. The choice of allocation method mainly affects pathways yielding high shares of co-products or producing co-products which effectively displace carbon intensive products (e.g., electricity). Renewable jet fuel can contribute to significant reduction of aviation-related GHG emissions, provided the right feedstock and conversion technology are used. The GHG emission performance of RJF may be further improved by using sustainable hydrogen sources or applying carbon capture and storage. Based on the character and impact of different co-product allocation methods, we recommend using energy and economic allocation (for non-energy co-products) at a global level, as it leverages the universal character of energy allocation while adequately valuing non-energy co-products.
NASA Astrophysics Data System (ADS)
Chambliss, S. E.; Silva, R.; West, J. J.; Zeinali, M.; Minjares, R.
2014-10-01
Exposure to ambient fine particular matter (PM2.5) was responsible for 3.2 million premature deaths in 2010 and is among the top ten leading risk factors for early death. Surface transportation is a significant global source of PM2.5 emissions and a target for new actions. The objective of this study is to estimate the global and national health burden of ambient PM2.5 exposure attributable to surface transportation emissions. This share of health burden is called the transportation attributable fraction (TAF), and is assumed equal to the proportional decrease in modeled ambient particulate matter concentrations when surface transportation emissions are removed. National population-weighted TAFs for 190 countries are modeled for 2005 using the MOZART-4 global chemical transport model. Changes in annual average concentration of PM2.5 at 0.5 × 0.67 degree horizontal resolution are based on a global emissions inventory and removal of all surface transportation emissions. Global population-weighted average TAF was 8.5 percent or 1.75 μg m-3 in 2005. Approximately 242 000 annual premature deaths were attributable to surface transportation emissions, dominated by China, the United States, the European Union and India. This application of TAF allows future Global Burden of Disease studies to estimate the sector-specific burden of ambient PM2.5 exposure. Additional research is needed to capture intraurban variations in emissions and exposure, and to broaden the range of health effects considered, including the effects of other pollutants.
The effects of household management practices on the global warming potential of urban lawns.
Gu, Chuanhui; Crane, John; Hornberger, George; Carrico, Amanda
2015-03-15
Nitrous oxide (N2O) emissions are an important component of the greenhouse gas (GHG) budget for urban turfgrasses. A biogeochemical model DNDC successfully captured the magnitudes and patterns of N2O emissions observed at an urban turfgrass system at the Richland Creek Watershed in Nashville, TN. The model was then used to study the long-term (i.e. 75 years) impacts of lawn management practice (LMP) on soil organic carbon sequestration rate (dSOC), soil N2O emissions, and net Global Warming Potentials (net GWPs). The model simulated N2O emissions and net GWP from the three management intensity levels over 75 years ranged from 0.75 to 3.57 kg N ha(-1)yr(-1) and 697 to 2443 kg CO2-eq ha(-1)yr(-1), respectively, which suggested that turfgrasses act as a net carbon emitter. Reduction of fertilization is most effective to mitigate the global warming potentials of turfgrasses. Compared to the baseline scenario, halving fertilization rate and clipping recycle as an alternative to synthetic fertilizer can reduce net GWPs by 17% and 12%, respectively. In addition, reducing irrigation and mowing are also effective in lowering net GWPs. The minimum-maintenance LMP without irrigation and fertilization can reduce annual N2O emissions and net GWPs by approximately 53% and 70%, respectively, with the price of gradual depletion of soil organic carbon, when compared to the intensive-maintenance LMP. A lawn age-dependent best management practice is recommended: a high dose fertilizer input at the initial stage of lawn establishment to enhance SOC sequestration, followed by decreasing fertilization rate when the lawn ages to minimize N2O emissions. A minimum-maintained LMP with clipping recycling, and minimum irrigation and mowing, is recommended to mitigate global warming effects from urban turfgrass systems. Among all practices, clipping recycle may be a relatively malleable behavior and, therefore, a good target for interventions seeking to reduce the environmental impacts of lawn management through public education. Our results suggest that a long-term or a chronosequence study of turfgrasses with varying ages is warranted to capture the complete dynamics of contribution of turfgrasses to global warming. Copyright © 2015 Elsevier Ltd. All rights reserved.
The pivotal role of perceived scientific consensus in acceptance of science
NASA Astrophysics Data System (ADS)
Lewandowsky, Stephan; Gignac, Gilles E.; Vaughan, Samuel
2013-04-01
Although most experts agree that CO2 emissions are causing anthropogenic global warming (AGW), public concern has been declining. One reason for this decline is the `manufacture of doubt' by political and vested interests, which often challenge the existence of the scientific consensus. The role of perceived consensus in shaping public opinion is therefore of considerable interest: in particular, it is unknown whether consensus determines people's beliefs causally. It is also unclear whether perception of consensus can override people's `worldviews', which are known to foster rejection of AGW. Study 1 shows that acceptance of several scientific propositions--from HIV/AIDS to AGW--is captured by a common factor that is correlated with another factor that captures perceived scientific consensus. Study 2 reveals a causal role of perceived consensus by showing that acceptance of AGW increases when consensus is highlighted. Consensus information also neutralizes the effect of worldview.
Lin, Hsiao-Wen; Jin, Yufang; Giglio, Louis; Foley, Jonathan A; Randerson, James T
2012-06-01
Fires in agricultural ecosystems emit greenhouse gases and aerosols that influence climate on multiple spatial and temporal scales. Annex 1 countries of the United Nations Framework Convention on Climate Change (UNFCCC), many of which ratified the Kyoto Protocol, are required to report emissions of CH4 and N2O from these fires annually. In this study, we evaluated several aspects of this reporting system, including the optimality of the crops targeted by the UNFCCC globally and within Annex 1 countries, and the consistency of emissions inventories among different countries. We also evaluated the success of individual countries in capturing interannual variability and long-term trends in agricultural fire activity. In our approach, we combined global high-resolution maps of crop harvest area and production, derived from satellite maps and ground-based census data, with Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) measurements of active fires. At a global scale, we found that adding ground nuts (e.g., peanuts), cocoa, cotton and oil palm, and removing potato, oats, rye, and pulse other from the list of 14 crops targeted by the UNFCCC increased the percentage of active fires covered by the reporting system by 9%. Optimization led to a different recommended list for Annex 1 countries, requiring the addition of sunflower, cotton, rapeseed, and alfalfa and the removal of beans, sugarcane, pulse others, and tuber-root others. Extending emissions reporting to all Annex 1 countries (from the current set of 19 countries) would increase the efficacy of the reporting system from 6% to 15%, and further including several non-Annex 1 countries (Argentina, Brazil, China, India, Indonesia, Thailand, Kazakhstan, Mexico, and Nigeria) would capture over 55% of active fires in croplands worldwide. Analyses of interannual trends from the United States and Australia showed the importance of both intensity of fire use and crop production in controlling year-to-year variations in agricultural fire emissions. Remote sensing provides an effective means for evaluating some aspects of the current UNFCCC emissions reporting system; and, if combined with census data, field experiments and expert opinion, has the potential to improve the robustness of the next generation inventory system.
40 CFR 63.7852 - What definitions apply to this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... hot metal, usually with dry air or nitrogen, to remove sulfur. Deviation means any instance in which... capture and collection of secondary emissions from a basic oxygen process furnace. Sinter cooler means the...
40 CFR 63.7852 - What definitions apply to this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... hot metal, usually with dry air or nitrogen, to remove sulfur. Deviation means any instance in which... capture and collection of secondary emissions from a basic oxygen process furnace. Sinter cooler means the...
40 CFR 63.7852 - What definitions apply to this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... hot metal, usually with dry air or nitrogen, to remove sulfur. Deviation means any instance in which... capture and collection of secondary emissions from a basic oxygen process furnace. Sinter cooler means the...
40 CFR 63.7852 - What definitions apply to this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... hot metal, usually with dry air or nitrogen, to remove sulfur. Deviation means any instance in which... capture and collection of secondary emissions from a basic oxygen process furnace. Sinter cooler means the...
40 CFR 63.7852 - What definitions apply to this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... hot metal, usually with dry air or nitrogen, to remove sulfur. Deviation means any instance in which... capture and collection of secondary emissions from a basic oxygen process furnace. Sinter cooler means the...
40 CFR 60.276a - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2014 CFR
2014-07-01
... device, and continuous monitoring equipment; (4) Flow diagram of process and emission capture equipment... at values exceeding ±15 percent of the value established under § 60.274a(c) or operation at flow...
40 CFR 60.276 - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2010 CFR
2010-07-01
...; (4) Flow diagram of process and emission capture equipment including other equipment or process(es... values exceeding ±15 percent of the value established under § 60.274(c) or operation at flow rates lower...
40 CFR 60.276 - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2014 CFR
2014-07-01
...; (4) Flow diagram of process and emission capture equipment including other equipment or process(es... values exceeding ±15 percent of the value established under § 60.274(c) or operation at flow rates lower...
40 CFR 60.276 - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2012 CFR
2012-07-01
...; (4) Flow diagram of process and emission capture equipment including other equipment or process(es... values exceeding ±15 percent of the value established under § 60.274(c) or operation at flow rates lower...
40 CFR 60.276a - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
... device, and continuous monitoring equipment; (4) Flow diagram of process and emission capture equipment... at values exceeding ±15 percent of the value established under § 60.274a(c) or operation at flow...
40 CFR 60.276a - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2013 CFR
2013-07-01
... device, and continuous monitoring equipment; (4) Flow diagram of process and emission capture equipment... at values exceeding ±15 percent of the value established under § 60.274a(c) or operation at flow...
40 CFR 60.276a - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2010 CFR
2010-07-01
... device, and continuous monitoring equipment; (4) Flow diagram of process and emission capture equipment... at values exceeding ±15 percent of the value established under § 60.274a(c) or operation at flow...
40 CFR 60.276 - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2013 CFR
2013-07-01
...; (4) Flow diagram of process and emission capture equipment including other equipment or process(es... values exceeding ±15 percent of the value established under § 60.274(c) or operation at flow rates lower...
40 CFR 60.276a - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2012 CFR
2012-07-01
... device, and continuous monitoring equipment; (4) Flow diagram of process and emission capture equipment... at values exceeding ±15 percent of the value established under § 60.274a(c) or operation at flow...
40 CFR 60.276 - Recordkeeping and reporting requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
...; (4) Flow diagram of process and emission capture equipment including other equipment or process(es... values exceeding ±15 percent of the value established under § 60.274(c) or operation at flow rates lower...
Front page or "buried" beneath the fold? Media coverage of carbon capture and storage.
Boyd, Amanda D; Paveglio, Travis B
2014-05-01
Media can affect public views and opinions on science, policy and risk issues. This is especially true of a controversial emerging technology that is relatively unknown. The study presented here employs a media content analysis of carbon capture and storage (CCS), one potential strategy to reduce greenhouse gas emissions. The authors analyzed all mentions of CCS in two leading Canadian national newspapers and two major western regional newspapers from the first article that discussed CCS in 2004 to the end of 2009 (825 articles). An in-depth content analysis was conducted to examine factors relating to risk from CCS, how the technology was portrayed and if coverage was negatively or positively biased. We conclude by discussing the possible impact of media coverage on support or opposition to CCS adoption.
Coping with carbon: a near-term strategy to limit carbon dioxide emissions from power stations.
Breeze, Paul
2008-11-13
Burning coal to generate electricity is one of the key sources of atmospheric carbon dioxide emissions; so, targeting coal-fired power plants offers one of the easiest ways of reducing global carbon emissions. Given that the world's largest economies all rely heavily on coal for electricity production, eliminating coal combustion is not an option. Indeed, coal consumption is likely to increase over the next 20-30 years. However, the introduction of more efficient steam cycles will improve the emission performance of these plants over the short term. To achieve a reduction in carbon emissions from coal-fired plant, however, it will be necessary to develop and introduce carbon capture and sequestration technologies. Given adequate investment, these technologies should be capable of commercial development by ca 2020.
Can dust emission mechanisms be determined from field measurements?
NASA Astrophysics Data System (ADS)
Klose, Martina; Webb, Nicholas; Gill, Thomas E.; Van Pelt, Scott; Okin, Gregory
2017-04-01
Field observations are needed to develop and test theories on dust emission for use in dust modeling systems. The dust emission mechanism (aerodynamic entrainment, saltation bombardment, aggregate disintegration) as well as the amount and particle-size distribution of emitted dust may vary under sediment supply- and transport-limited conditions. This variability, which is caused by heterogeneity of the surface and the atmosphere, cannot be fully captured in either field measurements or models. However, uncertainty in dust emission modeling can be reduced through more detailed observational data on the dust emission mechanism itself. To date, most measurements do not provide enough information to allow for a determination of the mechanisms leading to dust emission and often focus on a small variety of soil and atmospheric settings. Additionally, data sets are often not directly comparable due to different measurement setups. As a consequence, the calibration of dust emission schemes has so far relied on a selective set of observations, which leads to an idealization of the emission process in models and thus affects dust budget estimates. Here, we will present results of a study which aims to decipher the dust emission mechanism from field measurements as an input for future model development. Detailed field measurements are conducted, which allow for a comparison of dust emission for different surface and atmospheric conditions. Measurements include monitoring of the surface, loose erodible material, transported sediment, and meteorological data, and are conducted in different environmental settings in the southwestern United States. Based on the field measurements, a method is developed to differentiate between the different dust emission mechanisms.
NASA Astrophysics Data System (ADS)
Riddick, S. N.; Blackall, T. D.; Dragosits, U.; Tang, Y. S.; Moring, A.; Daunt, F.; Wanless, S.; Hamer, K. C.; Sutton, M. A.
2017-07-01
Many studies in recent years have highlighted the ecological implications of adding reactive nitrogen (Nr) to terrestrial ecosystems. Seabird colonies represent a situation with concentrated sources of Nr, through excreted and accumulated guano, often occurring in otherwise nutrient-poor areas. To date, there has been little attention given to modelling N flows in this context, and particularly to quantifying the relationship between ammonia (NH3) emissions and meteorology. This paper presents a dynamic mass-flow model (GUANO) that simulates temporal variations in NH3 emissions from seabird guano. While the focus is on NH3 emissions, the model necessarily also treats the interaction with wash-off as far as this affects NH3. The model is validated using NH3 emissions measurements from seabird colonies across a range of climates, from sub-polar to tropical. In simulations for hourly time-resolved data, the model is able to capture the observed dependence of NH3 emission on environmental variables. With temperature and wind speed having the greatest effects on emission for the cases considered. In comparison with empirical data, the percentage of excreted nitrogen that volatilizes as NH3 is found to range from 2% to 67% (based on measurements), with the GUANO model providing a range of 2%-82%. The model provides a tool that can be used to investigate the meteorological dependence of NH3 emissions from seabird guano and provides a starting point to refine models of NH3 emissions from other sources.
Geospatial analysis of near-term potential for carbon-negative bioenergy in the United States
Baik, Ejeong; Turner, Peter A.; Mach, Katharine J.; Field, Christopher B.; Benson, Sally M.
2018-01-01
Bioenergy with carbon capture and storage (BECCS) is a negative-emissions technology that may play a crucial role in climate change mitigation. BECCS relies on the capture and sequestration of carbon dioxide (CO2) following bioenergy production to remove and reliably sequester atmospheric CO2. Previous BECCS deployment assessments have largely overlooked the potential lack of spatial colocation of suitable storage basins and biomass availability, in the absence of long-distance biomass and CO2 transport. These conditions could constrain the near-term technical deployment potential of BECCS due to social and economic barriers that exist for biomass and CO2 transport. This study leverages biomass production data and site-specific injection and storage capacity estimates at high spatial resolution to assess the near-term deployment opportunities for BECCS in the United States. If the total biomass resource available in the United States was mobilized for BECCS, an estimated 370 Mt CO2⋅y−1 of negative emissions could be supplied in 2020. However, the absence of long-distance biomass and CO2 transport, as well as limitations imposed by unsuitable regional storage and injection capacities, collectively decrease the technical potential of negative emissions to 100 Mt CO2⋅y−1. Meeting this technical potential may require large-scale deployment of BECCS technology in more than 1,000 counties, as well as widespread deployment of dedicated energy crops. Specifically, the Illinois basin, Gulf region, and western North Dakota have the greatest potential for near-term BECCS deployment. High-resolution spatial assessment as conducted in this study can inform near-term opportunities that minimize social and economic barriers to BECCS deployment. PMID:29531081
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sinistore, Julie C.; Reinemann, D. J.; Izaurralde, Roberto C.
Spatial variability in yields and greenhouse gas emissions from soils has been identified as a key source of variability in life cycle assessments (LCAs) of agricultural products such as cellulosic ethanol. This study aims to conduct an LCA of cellulosic ethanol production from switchgrass in a way that captures this spatial variability and tests results for sensitivity to using spatially averaged results. The Environment Policy Integrated Climate (EPIC) model was used to calculate switchgrass yields, greenhouse gas (GHG) emissions, and nitrogen and phosphorus emissions from crop production in southern Wisconsin and Michigan at the watershed scale. These data were combinedmore » with cellulosic ethanol production data via ammonia fiber expansion and dilute acid pretreatment methods and region-specific electricity production data into an LCA model of eight ethanol production scenarios. Standard deviations from the spatial mean yields and soil emissions were used to test the sensitivity of net energy ratio, global warming potential intensity, and eutrophication and acidification potential metrics to spatial variability. Substantial variation in the eutrophication potential was also observed when nitrogen and phosphorus emissions from soils were varied. This work illustrates the need for spatially explicit agricultural production data in the LCA of biofuels and other agricultural products.« less
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.
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.
NASA Astrophysics Data System (ADS)
Ryu, Donghyeon; Castaño, Nicolas; Bhakta, Raj; Kimberley, Jamie
2017-08-01
The objective of this study is to understand light emission characteristics of fracto-mechanoluminescent (FML) europium tetrakis(dibenzoylmethide)-triethylammonium (EuD4TEA) crystals under high strain-rate compressive loading. As a sensing material that can play a pivotal role for the self-powered impact sensor technology, it is important to understand transformative light emission characteristics of the FML EuD4TEA crystals under high strain-rate compressive loading. First, EuD4TEA crystals were synthesized and embedded into polydimethylsiloxane (PDMS) elastomer to fabricate EuD4TEA-PDMS composite test specimens. Second, the prepared EuD4TEA-PDMS composites were tested using the modified Kolsky bar setup equipped with a high-speed camera. Third, FML light emission was captured to yield 12 bit grayscale video footage, which was processed to quantify the FML light emission. Finally, quantitative parameters were generated by taking into account pixel values and population of pixels of the 12 bit grayscale images to represent FML light intensity. The FML light intensity was correlated with high strain-rate compressive strain and strain rate to understand the FML light emission characteristics under high strain-rate compressive loading that can result from impact occurrences.
On the polarization of the green emission of polyfluorenes
NASA Astrophysics Data System (ADS)
Yang, X. H.; Neher, D.; Spitz, C.; Zojer, E.; Brédas, J. L.; Güntner, R.; Scherf, U.
2003-10-01
An experimental and theoretical study of the anisotropic optical properties of polyfluorenes (PFs) bearing ketonic defects is presented. Polarized emission experiments performed on photooxidized aligned PF layers indicate that the transition dipole of the "green" CT π-π* transition of the keto-defect is oriented parallel to the chain direction. It is further observed that the polarization ratio of the green emission is slightly smaller than that of the blue emission component originating from undisturbed chains. Quantum mechanical calculations have been performed to support these observations. It is shown that the transition dipole moment of the CT π-π* transition of the defect is slightly misaligned with respect to the π-π* transition of the undisturbed PF chain, and that the angle between both depends on the chain conformation. For the most probably 5/2 helical conformation, this angle is, however, smaller than 5°. Further, polarized PL spectroscopy with polarized excitation has been performed to determine the extent of energy migration prior to emission from the keto-defect. For excitation at 380 nm, the polarization ratio of the green emission is essentially independent of the excitation polarization, indicating almost complete depolarization of the excitation before it is captured at a defect site. In contrast to this, energy migration after direct excitation of the keto-defect is inefficient or even absent.
MethaneSat: Detecting Methane Emissions in the Barnett Shale Region
NASA Astrophysics Data System (ADS)
Propp, A. M.; Benmergui, J. S.; Turner, A. J.; Wofsy, S. C.
2017-12-01
In this study, we investigate the new information that will be provided by MethaneSat, a proposed satellite that will measure the total column dry-air mole fraction of methane at 1x1 km or 2x2 km spatial resolution with 0.1-0.2% random error. We run an atmospheric model to simulate MethaneSat's ability to characterize methane emissions from the Barnett Shale, a natural gas province in Texas. For comparison, we perform observation system simulation experiments (OSSEs) for MethaneSat, the National Oceanic and Atmospheric administration (NOAA) surface and aircraft network, and Greenhouse Gases Observing Satellite (GOSAT). The results demonstrate the added benefit that MethaneSat would provide in our efforts to monitor and report methane emissions. We find that MethaneSat successfully quantifies total methane emissions in the region, as well as their spatial distribution and steep gradients. Under the same test conditions, both the NOAA network and GOSAT fail to capture this information. Furthermore, we find that the results for MethaneSat depend far less on the prior emission estimate than do those for the other observing systems, demonstrating the benefit of high sampling density. The results suggest that MethaneSat would be an incredibly useful tool for obtaining detailed methane emission information from oil and gas provinces around the world.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Firestone, Ryan; Marnay, Chris
The on-site generation of electricity can offer buildingowners and occupiers financial benefits as well as social benefits suchas reduced grid congestion, improved energy efficiency, and reducedgreenhouse gas emissions. Combined heat and power (CHP), or cogeneration,systems make use of the waste heat from the generator for site heatingneeds. Real-time optimal dispatch of CHP systems is difficult todetermine because of complicated electricity tariffs and uncertainty inCHP equipment availability, energy prices, and system loads. Typically,CHP systems use simple heuristic control strategies. This paper describesa method of determining optimal control in real-time and applies it to alight industrial site in San Diego, California, tomore » examine: 1) the addedbenefit of optimal over heuristic controls, 2) the price elasticity ofthe system, and 3) the site-attributable greenhouse gas emissions, allunder three different tariff structures. Results suggest that heuristiccontrols are adequate under the current tariff structure and relativelyhigh electricity prices, capturing 97 percent of the value of thedistributed generation system. Even more value could be captured bysimply not running the CHP system during times of unusually high naturalgas prices. Under hypothetical real-time pricing of electricity,heuristic controls would capture only 70 percent of the value ofdistributed generation.« less
Role of hydrogen in volatile behaviour of defects in SiO2-based electronic devices
NASA Astrophysics Data System (ADS)
Wimmer, Yannick; El-Sayed, Al-Moatasem; Gös, Wolfgang; Grasser, Tibor; Shluger, Alexander L.
2016-06-01
Charge capture and emission by point defects in gate oxides of metal-oxide-semiconductor field-effect transistors (MOSFETs) strongly affect reliability and performance of electronic devices. Recent advances in experimental techniques used for probing defect properties have led to new insights into their characteristics. In particular, these experimental data show a repeated dis- and reappearance (the so-called volatility) of the defect-related signals. We use multiscale modelling to explain the charge capture and emission as well as defect volatility in amorphous SiO2 gate dielectrics. We first briefly discuss the recent experimental results and use a multiphonon charge capture model to describe the charge-trapping behaviour of defects in silicon-based MOSFETs. We then link this model to ab initio calculations that investigate the three most promising defect candidates. Statistical distributions of defect characteristics obtained from ab initio calculations in amorphous SiO2 are compared with the experimentally measured statistical properties of charge traps. This allows us to suggest an atomistic mechanism to explain the experimentally observed volatile behaviour of defects. We conclude that the hydroxyl-E' centre is a promising candidate to explain all the observed features, including defect volatility.
Temperature dependence of carrier capture by defects in gallium arsenide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wampler, William R.; Modine, Normand A.
2015-08-01
This report examines the temperature dependence of the capture rate of carriers by defects in gallium arsenide and compares two previously published theoretical treatments of this based on multi phonon emission (MPE). The objective is to reduce uncertainty in atomistic simulations of gain degradation in III-V HBTs from neutron irradiation. A major source of uncertainty in those simulations is poor knowledge of carrier capture rates, whose values can differ by several orders of magnitude between various defect types. Most of this variation is due to different dependence on temperature, which is closely related to the relaxation of the defect structuremore » that occurs as a result of the change in charge state of the defect. The uncertainty in capture rate can therefore be greatly reduced by better knowledge of the defect relaxation.« less
Many-body formulation of carriers capture time in quantum dots applicable in device simulation codes
NASA Astrophysics Data System (ADS)
Vallone, Marco
2010-03-01
We present an application of Green's functions formalism to calculate in a simplified but rigorous way electrons and holes capture time in quantum dots in closed form as function of carrier density, levels confinement potential, and temperature. Carrier-carrier (Auger) scattering and single LO-phonon emission are both addressed accounting for dynamic effects of the potential screening in the single plasmon pole approximation of the dielectric function. Regarding the LO-phonons interaction, the formulation evidences the role of the dynamic screening from wetting-layer carriers in comparison with its static limit, describes the interplay between screening and Fermi band filling, and offers simple expressions for capture time, suitable for modeling implementation.
Commercialization Development of Oxygen Fired CFB for Greenhouse Gas Control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nsakala ya Nsakala; Gregory N. Liljedahl; David G. Turek
2007-03-31
Given that fossil fuel fired power plants are among the largest and most concentrated producers of CO{sub 2} emissions, recovery and sequestration of CO{sub 2} from the flue gas of such plants has been identified as one of the primary means for reducing anthropogenic (i.e., man-made) CO{sub 2} emissions. In 2001, ALSTOM Power Inc. (ALSTOM) began a two-phase program to investigate the feasibility of various carbon capture technologies. This program was sponsored under a Cooperative Agreement from the US Department of Energy's National Energy Technology Laboratory (DOE). The first phase entailed a comprehensive study evaluating the technical feasibility and economicsmore » of alternate CO{sub 2} capture technologies applied to Greenfield US coal-fired electric generation power plants. Thirteen cases, representing various levels of technology development, were evaluated. Seven cases represented coal combustion in CFB type equipment. Four cases represented Integrated Gasification Combined Cycle (IGCC) systems. Two cases represented advanced Chemical Looping Combined Cycle systems. Marion, et al. reported the details of this work in 2003. One of the thirteen cases studied utilized an oxygen-fired circulating fluidized bed (CFB) boiler. In this concept, the fuel is fired with a mixture of oxygen and recirculated flue gas (mainly CO{sub 2}). This combustion process yields a flue gas containing over 80 percent (by volume) CO{sub 2}. This flue gas can be processed relatively easily to enrich the CO{sub 2} content to over 96 percent for use in enhanced oil or gas recovery (EOR or EGR) or simply dried for sequestration. The Phase I study identified the O{sub 2}-fired CFB as having a near term development potential, because it uses conventional commercial CFB technology and commercially available CO{sub 2} capture enabling technologies such as cryogenic air separation and simple rectification or distillation gas processing systems. In the long term, air separation technology advancements offer significant reductions in power requirements, which would improve plant efficiency and economics for the oxygen-fired technology. The second phase consisted of pilot-scale testing followed by a refined performance and economic evaluation of the O{sub 2} fired CFB concept. As a part of this workscope, ALSTOM modified its 3 MW{sub th} (9.9 MMBtu/hr) Multiuse Test Facility (MTF) pilot plant to operate with O{sub 2}/CO{sub 2} mixtures of up to 70 percent O{sub 2} by volume. Tests were conducted with coal and petroleum coke. The test objectives were to determine the impacts of oxygen firing on heat transfer, bed dynamics, potential agglomeration, and gaseous and particulate emissions. The test data results were used to refine the design, performance, costs, and economic models developed in Phase-I for the O{sub 2}-fired CFB with CO{sub 2} capture. Nsakala, Liljedahl, and Turek reported results from this study in 2004. ALSTOM identified several items needing further investigation in preparation for large scale demonstration of the oxygen-fired CFB concept, namely: (1) Operation and performance of the moving bed heat exchanger (MBHE) to avoid recarbonation and also for cost savings compared to the standard bubbling fluid bed heat exchanger (FBHE); (2) Performance of the back-end flash dryer absorber (FDA) for sulfur capture under high CO{sub 2}/high moisture flue gas environment using calcined limestone in the fly ash and using fresh commercial lime directly in the FDA; (3) Determination of the effect of recarbonation on fouling in the convective pass; (4) Assessment of the impact of oxygen firing on the mercury, other trace elements, and volatile organic compound (VOC) emissions; and (5) Develop a proposal-level oxygen-fired retrofit design for a relatively small existing CFB steam power plant in preparation for a large-scale demonstration of the O{sub 2} fired CFB concept. Hence, ALSTOM responded to a DOE Solicitation to address all these issues with further O{sub 2} fired MTF pilot testing and a subsequent retrofit design study of oxygen firing and CO{sub 2} capture on an existing air-fired CFB plant. ALSTOM received a contract award from the DOE to conduct a project entitled 'Commercialization Development of Oxygen Fired CFB for Greenhouse Gas Control', under Cooperative Agreement DE-FC26-04NT42205 that is the subject of this topical report.« less
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.
Integrated gasification combined cycle using Egyptian Maghara coal-rice straw feedstock.
Hegazy, A; Ghallab, A O; Ashour, F H
2017-06-01
Rice straw is an agricultural waste that causes an annoying problem in Egypt if it is not well exploited. This study focuses on using this waste in power generation by co-gasification of Egyptian Maghara coal and rice straw blends using entrained flow gasifier technology. Aspen Plus was used to conduct a parametric study for investigation of the effect of changing the inputs to the gasifier on the produced gas composition. Three different input parameters, influencing the performance of the gasifier, including the percentage of coal to rice straw in the blend, the fraction of added water to the blend, and the mass percentage of oxygen with respect to the mass of the blend fed to the gasifier were analysed. Two alternative power production schemes (with and without carbon capturing) have been investigated. The obtained optimum feed conditions are: 40% coal in the feed blend, 20% water concentration in the feed slurry, and 80% oxygen with respect to the dry feed blend to the gasifier. For (10 0000 kg per hour) of the feed blend, the power generated was 270.1 MW in the case of non-carbon capturing, while in the case of carbon capturing, 263.52 MW was generated. Although it produces less power, applying carbon capturing techniques means handling less flue gas and thus using smaller gas turbines and results in more environmentally friendly emissions.
Fermi/LAT detection of a transient gamma-ray flare in the vicinity of the binary star DG CVn
Loh, Alan; Corbel, Stéphane; Dubus, Guillaume
2017-02-16
Solar flares are regularly detected by the Large Area Telescope (LAT) on board the Fermi satellite, however no γ-ray emission from other stellar eruptions has ever been captured. The Swift detection in 2014 April of a powerful outburst originating from DG CVn, with associated optical and radio emissions, enticed us to search for possible 0.1–100 GeV emission from this flaring nearby binary star using the Fermi/LAT. No γ-ray emission is detected from DG CVn in 2014, but we report a significant γ-ray excess in 2012 November, at a position consistent with that of the binary. There are no reports ofmore » contemporary flaring at other wavelengths from DG CVn or any other source within the error circle of the γ-ray source. As a result, we argue that the γ-ray flare is more likely to have been associated with a background blazar than with DG CVn and identify a candidate for follow-up study.« less
Tsai, Candace Su-Jung; Hofmann, Mario; Hallock, Marilyn; Ellenbecker, Michael; Kong, Jing
2015-11-01
This study performed a workplace evaluation of emission control using available air sampling filters and characterized the emitted particles captured in filters. Characterized particles were contained in the exhaust gas released from carbon nanotube (CNT) synthesis using chemical vapor deposition (CVD). Emitted nanoparticles were collected on grids to be analyzed using transmission electron microscopy (TEM). CNT clusters in the exhaust gas were collected on filters for investigation. Three types of filters, including Nalgene surfactant-free cellulose acetate (SFCA), Pall A/E glass fiber, and Whatman QMA quartz filters, were evaluated as emission control measures, and particles deposited in the filters were characterized using scanning transmission electron microscopy (STEM) to further understand the nature of particles emitted from this CNT production. STEM analysis for collected particles on filters found that particles deposited on filter fibers had a similar morphology on all three filters, that is, hydrophobic agglomerates forming circular beaded clusters on hydrophilic filter fibers on the collecting side of the filter. CNT agglomerates were found trapped underneath the filter surface. The particle agglomerates consisted mostly of elemental carbon regardless of the shapes. Most particles were trapped in filters and no particles were found in the exhaust downstream from A/E and quartz filters, while a few nanometer-sized and submicrometer-sized individual particles and filament agglomerates were found downstream from the SFCA filter. The number concentration of particles with diameters from 5 nm to 20 µm was measured while collecting particles on grids at the exhaust piping. Total number concentration was reduced from an average of 88,500 to 700 particle/cm(3) for the lowest found for all filters used. Overall, the quartz filter showed the most consistent and highest particle reduction control, and exhaust particles containing nanotubes were successfully collected and trapped inside this filter. As concern for the toxicity of engineered nanoparticles grows, there is a need to characterize emission from carbon nanotube synthesis processes and to investigate methods to prevent their environmental release. At this time, the particles emitted from synthesis were not well characterized when collected on filters, and limited information was available about filter performance to such emission. This field study used readily available sampling filters to collect nanoparticles from the exhaust gas of a carbon nanotube furnace. New agglomerates were found on filters from such emitted particles, and the performance of using the filters studied was encouraging in terms of capturing emissions from carbon nanotube synthesis.
Chatzinoff, Yonatan; Szczepanski, Debby; Bing, Chenchen; Shaikh, Sumbul; Wyman, Omar; Perry, Cameron E.; Richardson, James A.; Burns, Dennis K.; Evers, Bret M.; Greenberg, David E.; Chopra, Rajiv
2018-01-01
Treatment of prosthetic joint infections often involves multiple surgeries and prolonged antibiotic administration, resulting in a significant burden to patients and the healthcare system. We are exploring a non-invasive method to eradicate biofilm on metal implants utilizing high-frequency alternating magnetic fields (AMF) which can achieve surface induction heating. Although proof-of-concept studies demonstrate the ability of AMF to eradicate biofilm in vitro, there is a legitimate safety concern related to the potential for thermal damage to surrounding tissues when considering heating implanted metal objects. The goal of this study was to explore the feasibility of detecting acoustic emissions associated with boiling at the interface between a metal implant and surrounding soft tissue as a wireless safety sensing mechanism. Acoustic emissions generated during in vitro and in vivo AMF exposures were captured with a hydrophone, and the relationship with surface temperature analyzed. The effect of AMF exposure power, surrounding media composition, implant location within the AMF transmitter, and implant geometry on acoustic detection during AMF therapy was also evaluated. Acoustic emissions were reliably identified in both tissue-mimicking phantom and mouse studies, and their onset coincided with the implant temperature reaching the boiling threshold. The viscosity of the surrounding medium did not impact the production of acoustic emissions; however, emissions were not present when the medium was oil due to the higher boiling point. Results of simulations and in vivo studies suggest that short-duration, high-power AMF exposures combined with acoustic sensing can be used to minimize the amount of thermal damage in surrounding tissues. These studies support the hypothesis that detection of boiling associated acoustic emissions at a metal/tissue interface could serve as a real-time, wireless safety indicator during AMF treatment of biofilm on metallic implants. PMID:29746579
Cheng, Bingbing; Chatzinoff, Yonatan; Szczepanski, Debby; Bing, Chenchen; Shaikh, Sumbul; Wyman, Omar; Perry, Cameron E; Richardson, James A; Burns, Dennis K; Evers, Bret M; Greenberg, David E; Chopra, Rajiv
2018-01-01
Treatment of prosthetic joint infections often involves multiple surgeries and prolonged antibiotic administration, resulting in a significant burden to patients and the healthcare system. We are exploring a non-invasive method to eradicate biofilm on metal implants utilizing high-frequency alternating magnetic fields (AMF) which can achieve surface induction heating. Although proof-of-concept studies demonstrate the ability of AMF to eradicate biofilm in vitro, there is a legitimate safety concern related to the potential for thermal damage to surrounding tissues when considering heating implanted metal objects. The goal of this study was to explore the feasibility of detecting acoustic emissions associated with boiling at the interface between a metal implant and surrounding soft tissue as a wireless safety sensing mechanism. Acoustic emissions generated during in vitro and in vivo AMF exposures were captured with a hydrophone, and the relationship with surface temperature analyzed. The effect of AMF exposure power, surrounding media composition, implant location within the AMF transmitter, and implant geometry on acoustic detection during AMF therapy was also evaluated. Acoustic emissions were reliably identified in both tissue-mimicking phantom and mouse studies, and their onset coincided with the implant temperature reaching the boiling threshold. The viscosity of the surrounding medium did not impact the production of acoustic emissions; however, emissions were not present when the medium was oil due to the higher boiling point. Results of simulations and in vivo studies suggest that short-duration, high-power AMF exposures combined with acoustic sensing can be used to minimize the amount of thermal damage in surrounding tissues. These studies support the hypothesis that detection of boiling associated acoustic emissions at a metal/tissue interface could serve as a real-time, wireless safety indicator during AMF treatment of biofilm on metallic implants.
Do s-Process Enhanced Planetary Nebulae Have Unusual Dust Emission Spectra?
NASA Astrophysics Data System (ADS)
Dinerstein, Harriet; Sellgren, Kris; Sterling, Nicholas
2006-05-01
We propose to obtain IRS observations of the mid-infrared dust emission of a sample of Galactic planetary nebulae (PNs) which are known to have enrichments of elements produced in the precursor star by slow neutron-capture nucleosynthesis (the "s-process"). These enhanced abundances result from captures of free neutrons by Fe-peak nuclei following by convective mixing during the AGB; this "third dredge-up" is also responsible for increasing the surface abundance of carbon. Since PNs are the descendants of AGB stars and are often C-rich, it is not surprising that we find substantial enrichments of s-process products such as Ge, Se, and Kr in some PNs. Despite their low initial abundances, 1e-9 to 1e-10 times H, modest enrichments of neutron-capture elements can have observable effects. The spectral type S, a transitional class between O-rich and C-rich AGB stars, is characterized by prominent ZrO bands; Zr is produced in the s-process. We have attempted, without success, to detect gas-phase Zr in PNs. However, Zr is highly refractory. It can condense into ZrO2 or be incorporated into high-temperature rocky condensates in O-rich environments, while in C-rich environments it may form metallic carbides (i.e. ZrC, an analog of TiC). Indeed, Zr-Mo carbide inclusions found in some meteoritic presolar grains are thought to originate in the atmospheres of C-rich AGB stars. Other refractory s-process products (e.g. Sr, Ba) may also be incorporated into grains. High-quality Spitzer spectra of the dust emission in a set of PNs with known s-process enhancements - determined by us from gas-phase measurements of undepleted elements - will be valuable for comparison with laboratory spectroscopy of grain analogs. These comparisons will help determine whether the dredge-up of n-capture products affects the dust chemistry of PNs and may offer some new insights into the dust composition.
NASA Astrophysics Data System (ADS)
Correa Silva, R.; Larter, S.
2016-12-01
Atmospheric CO2 capture into biomass is one of the capture options for negative emission technologies, although proposed sequestration systems such as the permanent burial of total fresh biomass, algal lipids or soil amendment with biochar are yet to be successfully demonstrated as effective at scale. In the context of carbon sequestration, shallow geological reservoirs have not been exhaustively explored, even though they pose, away from groundwater protection zones, potentially low implementation cost, and geographically abundant potential carbon storage reservoirs. Typical carbon storage vectors considered, such as CO2 and biochar, are not suitable for shallow aquifer disposal, due either to cap rock containment requirements, or shallow aquifer CO2 densities, or issues related to formation damage from solid particles. Thus, a cost-effective technology, aimed at converting biomass into a large-scale carbon vector fit-for-disposal in shallow formations could be significant, linking promising carbon capture and containment strategies. In this work, we discuss the development of unconventional carbon vectors for subsurface storage in the form of Functionalized, Refractory and Aqueous Compatible Carbon Compounds (FRACCC), as a potential alternative negative emission technology (Larter et al., 2010). The concept is based on CO2 capture into microbial and algal biomass, followed by the modification of biomass constituents through facile chemical reactions aimed at rendering the biomass efficiently into a stable, biologically refractory but water soluble form, similar in some regards, to dissolved organic matter in the oceans, then sequestering the material in geological settings. As the injected material is not buoyant, containment specifications are more modest than for CO2 injection and potentially, more reservoirs could be accessible! This work analyses the technological, economic and societal implications of such potential FRACCC technologies, and make an assessment of whether such routes are likely to be technically, economically and politically viable.
MERCURY SPECIATION AND CAPTURE
In December 2000, the U.S. Environmental Protection Agency (USEPA) announced its intent to regulate mercury emissions from coal-fired electric utility steam generating plants. Maximum achievable control technology (MACT) requirements are to be proposed by December 2003 and finali...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-27
... operation and maintenance of this equipment. These standards rely on the capture and reduction of methane, carbon dioxide, and non-methane organic gas compound emissions by combustion devices (boilers, internal...
Hawaii Kilauea Volcano Belches a Toxic Brew
2008-04-04
On the night of March 25, 2008, the Advanced Spaceborne Thermal Emission and Reflection Radiometer instrument on NASA Terra satellite captured these thermal infrared images of Kilauea volcano on Hawaii Big Island. Kilauea was active at two locations.
Reducing Mercury Pollution from Artisanal and Small-Scale Gold Mining
To reduce airborne mercury emissions from these Gold Shops, EPA and the Argonne National Laboratory (ANL) have partnered to design a low cost, easily constructible technology called the Gold Shop Mercury Capture System (MCS).
Svečko, Rajko; Kusić, Dragan; Kek, Tomaž; Sarjaš, Andrej; Hančič, Aleš; Grum, Janez
2013-05-14
This paper presents an improved monitoring system for the failure detection of engraving tool steel inserts during the injection molding cycle. This system uses acoustic emission PZT sensors mounted through acoustic waveguides on the engraving insert. We were thus able to clearly distinguish the defect through measured AE signals. Two engraving tool steel inserts were tested during the production of standard test specimens, each under the same processing conditions. By closely comparing the captured AE signals on both engraving inserts during the filling and packing stages, we were able to detect the presence of macro-cracks on one engraving insert. Gabor wavelet analysis was used for closer examination of the captured AE signals' peak amplitudes during the filling and packing stages. The obtained results revealed that such a system could be used successfully as an improved tool for monitoring the integrity of an injection molding process.
Juno Captures Jupiter Glow in Infrared Light
2016-09-02
As NASA's Juno spacecraft approached Jupiter on Aug. 27, 2016, the Jovian Infrared Auroral Mapper (JIRAM) instrument captured the planet's glow in infrared light. The video is composed of 580 images collected over a period of about nine hours while Jupiter completed nearly a full rotation on its axis. The video shows the two parts composing the JIRAM imager: the lower one, in a red color scale, is used for mapping the planet's thermal emission at wavelengths around 4.8 microns; the upper one, in a blue color scale, is used to map the auroras at wavelengths around 3.45 microns. In this case the exposure time of the imager was optimized to observe the planet's thermal emission. However, it is possible to see a faint aurora and Jupiter's moon Io approaching the planet. The Great Red Spot is also visible just south of the planet's equator. A movie is available at http://photojournal.jpl.nasa.gov/catalog/PIA21036
Svečko, Rajko; Kusić, Dragan; Kek, Tomaž; Sarjaš, Andrej; Hančič, Aleš; Grum, Janez
2013-01-01
This paper presents an improved monitoring system for the failure detection of engraving tool steel inserts during the injection molding cycle. This system uses acoustic emission PZT sensors mounted through acoustic waveguides on the engraving insert. We were thus able to clearly distinguish the defect through measured AE signals. Two engraving tool steel inserts were tested during the production of standard test specimens, each under the same processing conditions. By closely comparing the captured AE signals on both engraving inserts during the filling and packing stages, we were able to detect the presence of macro-cracks on one engraving insert. Gabor wavelet analysis was used for closer examination of the captured AE signals' peak amplitudes during the filling and packing stages. The obtained results revealed that such a system could be used successfully as an improved tool for monitoring the integrity of an injection molding process. PMID:23673677
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swanson, Charles; Kaganovich, Igor D.
Complex structures on a material surface can significantly reduce the total secondary electron emission from that surface. The reduction occurs due to the capture of low-energy, true secondary electrons emitted at one point of the structure and intersecting another. We performed Monte Carlo calculations to demonstrate that fractal surfaces can reduce net secondary electron emission produced by the surface as compared to the flat surface. Specifically, we describe one surface, a “feathered” surface, which reduces the secondary electron emission yield more effectively than other previously considered configurations. Specifically, feathers grown onto a surface suppress secondary electron emission from shallow anglesmore » of incidence more effectively than velvet. Here, we find that, for the surface simulated, secondary electron emission yield remains below 20% of its un-suppressed value, even for shallow incident angles, where the velvet-only surface gives reduction factor of only 50%.« less
Swanson, Charles; Kaganovich, Igor D.
2017-07-24
Complex structures on a material surface can significantly reduce the total secondary electron emission from that surface. The reduction occurs due to the capture of low-energy, true secondary electrons emitted at one point of the structure and intersecting another. We performed Monte Carlo calculations to demonstrate that fractal surfaces can reduce net secondary electron emission produced by the surface as compared to the flat surface. Specifically, we describe one surface, a “feathered” surface, which reduces the secondary electron emission yield more effectively than other previously considered configurations. Specifically, feathers grown onto a surface suppress secondary electron emission from shallow anglesmore » of incidence more effectively than velvet. Here, we find that, for the surface simulated, secondary electron emission yield remains below 20% of its un-suppressed value, even for shallow incident angles, where the velvet-only surface gives reduction factor of only 50%.« less
NASA Astrophysics Data System (ADS)
Swanson, Charles; Kaganovich, Igor D.
2017-07-01
Complex structures on a material surface can significantly reduce the total secondary electron emission from that surface. The reduction occurs due to the capture of low-energy, true secondary electrons emitted at one point of the structure and intersecting another. We performed Monte Carlo calculations to demonstrate that fractal surfaces can reduce net secondary electron emission produced by the surface as compared to the flat surface. Specifically, we describe one surface, a "feathered" surface, which reduces the secondary electron emission yield more effectively than other previously considered configurations. Specifically, feathers grown onto a surface suppress secondary electron emission from shallow angles of incidence more effectively than velvet. We find that, for the surface simulated, secondary electron emission yield remains below 20% of its un-suppressed value, even for shallow incident angles, where the velvet-only surface gives reduction factor of only 50%.
CO2 Accounting and Risk Analysis for CO2 Sequestration at Enhanced Oil Recovery Sites.
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.
The cost of carbon capture and storage for natural gas combined cycle power plants.
Rubin, Edward S; Zhai, Haibo
2012-03-20
This paper examines the cost of CO(2) capture and storage (CCS) for natural gas combined cycle (NGCC) power plants. Existing studies employ a broad range of assumptions and lack a consistent costing method. This study takes a more systematic approach to analyze plants with an amine-based postcombustion CCS system with 90% CO(2) capture. We employ sensitivity analyses together with a probabilistic analysis to quantify costs for plants with and without CCS under uncertainty or variability in key parameters. Results for new baseload plants indicate a likely increase in levelized cost of electricity (LCOE) of $20-32/MWh (constant 2007$) or $22-40/MWh in current dollars. A risk premium for plants with CCS increases these ranges to $23-39/MWh and $25-46/MWh, respectively. Based on current cost estimates, our analysis further shows that a policy to encourage CCS at new NGCC plants via an emission tax or carbon price requires (at 95% confidence) a price of at least $125/t CO(2) to ensure NGCC-CCS is cheaper than a plant without CCS. Higher costs are found for nonbaseload plants and CCS retrofits.
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
Carbon Capture and Utilization in the Industrial Sector.
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.
NASA Astrophysics Data System (ADS)
Modine, Normand; Wright, Alan; Lee, Stephen
2015-03-01
Carrier recombination due to defects can have a major impact on device performance. The rate of defect-induced recombination is determined by both defect levels and carrier capture cross-sections. Density functional theory (DFT) has been widely and successfully used to predict defect levels, but only recently has work begun to focus on using DFT to determine carrier capture cross-sections. Lang and Henry worked out the fundamental theory of carrier-capture by multiphonon emission in the 1970s and showed that, above the Debye temperature, carrier-capture cross-sections differ between defects primarily due to differences in their carrier capture activation energies. We present an approach to using DFT to calculate carrier capture activation energies that does not depend on an assumed configuration coordinate and that fully accounts for anharmonic effects, which can substantially modify carrier activation energies. We demonstrate our approach for the -3/-2 level of the Ga vacancy in wurtzite GaN. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
NASA Astrophysics Data System (ADS)
Modine, N. A.; Wright, A. F.; Lee, S. R.
The rate of defect-induced carrier recombination is determined by both defect levels and carrier capture cross-sections. Density functional theory (DFT) has been widely and successfully used to predict defect levels, but only recently has work begun to focus on using DFT to determine carrier capture cross-sections. Lang and Henry developed the theory of carrier-capture by multiphonon emission in the 1970s and showed that carrier-capture cross-sections differ between defects primarily due to differences in their carrier capture activation energies. We present an approach to using DFT to calculate carrier capture activation energies that does not depend on an assumed configuration coordinate and that fully accounts for anharmonic effects, which can substantially modify carrier activation energies. We demonstrate our approach for intrinisic defects in GaAs and GaN and discuss how our results depend on the choice of exchange-correlation functional and the treatment of spin polarization. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.
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.