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Sample records for fuel co2 monitoring

  1. CO2-Neutral Fuels

    NASA Astrophysics Data System (ADS)

    Goede, Adelbert; van de Sanden, Richard

    2016-06-01

    Mimicking the biogeochemical cycle of System Earth, synthetic hydrocarbon fuels are produced from recycled CO2 and H2O powered by renewable energy. Recapturing CO2 after use closes the carbon cycle, rendering the fuel cycle CO2 neutral. Non-equilibrium molecular CO2 vibrations are key to high energy efficiency.

  2. CO2-neutral fuels

    NASA Astrophysics Data System (ADS)

    Goede, A. P. H.

    2015-08-01

    The need for storage of renewable energy (RE) generated by photovoltaic, concentrated solar and wind arises from the fact that supply and demand are ill-matched both geographically and temporarily. This already causes problems of overcapacity and grid congestion in countries where the fraction of RE exceeds the 20% level. A system approach is needed, which focusses not only on the energy source, but includes conversion, storage, transport, distribution, use and, last but not least, the recycling of waste. Furthermore, there is a need for more flexibility in the energy system, rather than relying on electrification, integration with other energy systems, for example the gas network, would yield a system less vulnerable to failure and better adapted to requirements. For example, long-term large-scale storage of electrical energy is limited by capacity, yet needed to cover weekly to seasonal demand. This limitation can be overcome by coupling the electricity net to the gas system, considering the fact that the Dutch gas network alone has a storage capacity of 552 TWh, sufficient to cover the entire EU energy demand for over a month. This lecture explores energy storage in chemicals bonds. The focus is on chemicals other than hydrogen, taking advantage of the higher volumetric energy density of hydrocarbons, in this case methane, which has an approximate 3.5 times higher volumetric energy density. More importantly, it allows the ready use of existing gas infrastructure for energy storage, transport and distribution. Intermittent wind electricity generated is converted into synthetic methane, the Power to Gas (P2G) scheme, by splitting feedstock CO2 and H2O into synthesis gas, a mixture of CO and H2. Syngas plays a central role in the synthesis of a range of hydrocarbon products, including methane, diesel and dimethyl ether. The splitting is accomplished by innovative means; plasmolysis and high-temperature solid oxygen electrolysis. A CO2-neutral fuel cycle is

  3. Use of Chia Plant to Monitor Urban Fossil Fuel CO2 Emission: An Example From Irvine, CA in 2010

    NASA Astrophysics Data System (ADS)

    Xu, X.; Stills, A.; Trumbore, S.; Randerson, J. T.; Yi, J.

    2011-12-01

    Δ14CO2 is a unique tracer for quantifying anthropogenic CO2 emissions. However, monitoring 14CO2 change and distribution in an urban environment is challenging because of its large spatial and temporal variations. We have tested the potential use of a chia plant (Salvia hispanica) as an alternative way to collect a time-integrated CO2 sample for radiocarbon analysis. The results show that Δ14C of the new growth of chia sprouts and chia leaves are consistent with the Δ14C of air samples collected during the growing period, indicating the new growth has no inherited C from seeds and thus records atmospheric 14CO2. Time-integrated air samples and chia leaf samples significantly reduced the noises of Δ14CO2 in an urban environment. We report here an example of monitoring 14CO2 change in Irvine, CA from Mar 2010 to Mar 2011 utilizing such a method. The results showed a clear seasonal cycle with high (close to remote air background level) Δ14C in summer and low Δ14C in winter months in this urban area. Excess (above remote air background) fossil fuel CO2 was calculated to be closed to 0 ppm in June to about 16 ppm from November 2010 to February 2011. Monthly mean Δ14CO2 was anti-correlated with monthly mean CO mixing ratio, indicating Δ14CO2 is mainly controlled by fossil fuel CO2 mixing with clean on-shore marine air. In summary, this study has shown encouraging result that chia plant can be potentially used as a convenient and inexpensive sampling method for time-integrated atmospheric 14CO2. Combined with other annual plants this provides the opportunity to map out time-integrated fossil fuel-derived CO2 in major cities at low cost. This in turn can be used to: 1) establish a baseline for fossil fuel emissions reductions in cities in the future; 2) provide invaluable information for validating emission models.

  4. CO2 Sequestration Crosswell Monitoring

    NASA Astrophysics Data System (ADS)

    Morency, C.; Luo, Y.; Tromp, J.

    2010-12-01

    Geologic sequestration of CO2, a green house gas, represents an effort to reduce the large amount of CO2 generated as a by-product of fossil fuels combustion and emitted into the atmosphere. This process of sequestration involves CO2 storage deep underground into highly permeable porous media sealed by caprock. "4D seismics" is a natural non-intrusive monitoring technique which involves 3D time-lapse seismic surveys. The success of monitoring CO2 movement relies upon a proper description of the physics of the problem. We realize time-lapse migrations comparing acoustic, elastic (with or without Gassmann's formulae), and poroelastic simulations of 4D seismic imaging. This approach highlights the influence of using different physical theories on interpreting seismic data, and, more importantly, on extracting the CO2 signature from the seismic wave field. We investigate various types of inversions using (1) P-wave traveltimes, (2) P- & S-wave traveltimes and (3) P- & S-wave traveltimes and amplitudes. Simulations are performed using a spectral-element method, and finite-frequency sensitivity kernels, used in the non-linear iterative inversions, are calculated based on an adjoint method. Biot's equations are implemented in the forward and adjoint simulations to account for poroelastic effects.

  5. Sensitivity of simulated CO2 concentration to regridding of global fossil fuel CO2 emissions

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Gurney, K. R.; Rayner, P.; Liu, Y.; Asefi-Najafabady, S.

    2014-06-01

    Errors in the specification or utilization of fossil fuel CO2 emissions within carbon budget or atmospheric CO2 inverse studies can alias the estimation of biospheric and oceanic carbon exchange. A key component in the simulation of CO2 concentrations arising from fossil fuel emissions is the spatial distribution of the emission near coastlines. Finite grid resolution can give rise to mismatches between the emissions and simulated atmospheric dynamics which differ over land or water. We test these mismatches by examining simulated global atmospheric CO2 concentration driven by two different approaches to regridding fossil fuel CO2 emissions. The two approaches are: (1) a commonly-used method that allocates emissions to gridcells with no attempt to ensure dynamical consistency with atmospheric transport; (2) an improved method that reallocates emissions to gridcells to ensure dynamically consistent results. Results show large spatial and temporal differences in the simulated CO2 concentration when comparing these two approaches. The emissions difference ranges from -30.3 Tg C gridcell-1 yr-1 (-3.39 kg C m-2 yr-1) to +30.0 Tg C gridcell-1 yr-1 (+2.6 kg C m-2 yr-1) along coastal margins. Maximum simulated annual mean CO2 concentration differences at the surface exceed ±6 ppm at various locations and times. Examination of the current CO2 monitoring locations during the local afternoon, consistent with inversion modeling system sampling and measurement protocols, finds maximum hourly differences at 38 stations exceed ±0.10 ppm with individual station differences exceeding -32 ppm. The differences implied by not accounting for this dynamical consistency problem are largest at monitoring sites proximal to large coastal urban areas and point sources. These results suggest that studies comparing simulated to observed atmospheric CO2 concentration, such as atmospheric CO2 inversions, must take measures to correct for this potential problem and ensure flux and dynamical

  6. Atmospheric measurement of point source fossil fuel CO2 emissions

    NASA Astrophysics Data System (ADS)

    Turnbull, J. C.; Keller, E. D.; Baisden, W. T.; Brailsford, G.; Bromley, T.; Norris, M.; Zondervan, A.

    2013-11-01

    We use the Kapuni Gas Treatment Plant to examine methodologies for atmospheric monitoring of point source fossil fuel CO2 (CO2ff) emissions. The Kapuni plant, located in rural New Zealand, removes CO2 from locally extracted natural gas and vents that CO2 to the atmosphere, at a rate of ~0.1 Tg carbon per year. The plant is located in a rural dairy farming area, with no other significant CO2ff sources nearby, but large, diurnally varying, biospheric CO2 fluxes from the surrounding highly productive agricultural grassland. We made flask measurements of CO2 and 14CO2 (from which we derive the CO2ff component) and in situ measurements of CO2 downwind of the Kapuni plant, using a Helikite to sample transects across the emission plume from the surface up to 100 m a.g.l. We also determined the surface CO2ff content averaged over several weeks from the 14CO2 content of grass samples collected from the surrounding area. We use the WindTrax plume dispersion model to compare the atmospheric observations with the emissions reported by the Kapuni plant, and to determine how well atmospheric measurements can constrain the emissions. The model has difficulty accurately capturing the fluctuations and short-term variability in the Helikite samples, but does quite well in representing the observed CO2ff in 15 min averaged surface flask samples and in ~1 week integrated CO2ff averages from grass samples. In this pilot study, we found that using grass samples, the modeled and observed CO2ff emissions averaged over one week agreed to within 30%. The results imply that greater verification accuracy may be achieved by including more detailed meteorological observations and refining 14CO2 sampling strategies.

  7. Geophysical monitoring technology for CO2 sequestration

    NASA Astrophysics Data System (ADS)

    Ma, Jin-Feng; Li, Lin; Wang, Hao-Fan; Tan, Ming-You; Cui, Shi-Ling; Zhang, Yun-Yin; Qu, Zhi-Peng; Jia, Ling-Yun; Zhang, Shu-Hai

    2016-06-01

    Geophysical techniques play key roles in the measuring, monitoring, and verifying the safety of CO2 sequestration and in identifying the efficiency of CO2-enhanced oil recovery. Although geophysical monitoring techniques for CO2 sequestration have grown out of conventional oil and gas geophysical exploration techniques, it takes a long time to conduct geophysical monitoring, and there are many barriers and challenges. In this paper, with the initial objective of performing CO2 sequestration, we studied the geophysical tasks associated with evaluating geological storage sites and monitoring CO2 sequestration. Based on our review of the scope of geophysical monitoring techniques and our experience in domestic and international carbon capture and sequestration projects, we analyzed the inherent difficulties and our experiences in geophysical monitoring techniques, especially, with respect to 4D seismic acquisition, processing, and interpretation.

  8. Sensitivity of simulated CO2 concentration to regridding of global fossil fuel CO2 emissions

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Gurney, K. R.; Rayner, P.; Liu, Y.; Asefi-Najafabady, S.

    2014-12-01

    Errors in the specification or utilization of fossil fuel CO2 emissions within carbon budget or atmospheric CO2 inverse studies can alias the estimation of biospheric and oceanic carbon exchange. A key component in the simulation of CO2 concentrations arising from fossil fuel emissions is the spatial distribution of the emission near coastlines. Regridding of fossil fuel CO2 emissions (FFCO2) from fine to coarse grids to enable atmospheric transport simulations can give rise to mismatches between the emissions and simulated atmospheric dynamics which differ over land or water. For example, emissions originally emanating from the land are emitted from a grid cell for which the vertical mixing reflects the roughness and/or surface energy exchange of an ocean surface. We test this potential "dynamical inconsistency" by examining simulated global atmospheric CO2 concentration driven by two different approaches to regridding fossil fuel CO2 emissions. The two approaches are as follows: (1) a commonly used method that allocates emissions to grid cells with no attempt to ensure dynamical consistency with atmospheric transport and (2) an improved method that reallocates emissions to grid cells to ensure dynamically consistent results. Results show large spatial and temporal differences in the simulated CO2 concentration when comparing these two approaches. The emissions difference ranges from -30.3 TgC grid cell-1 yr-1 (-3.39 kgC m-2 yr-1) to +30.0 TgC grid cell-1 yr-1 (+2.6 kgC m-2 yr-1) along coastal margins. Maximum simulated annual mean CO2 concentration differences at the surface exceed ±6 ppm at various locations and times. Examination of the current CO2 monitoring locations during the local afternoon, consistent with inversion modeling system sampling and measurement protocols, finds maximum hourly differences at 38 stations exceed ±0.10 ppm with individual station differences exceeding -32 ppm. The differences implied by not accounting for this dynamical

  9. Inferring high-resolution fossil fuel CO2 records at continental sites from combined 14CO2 and CO observations

    NASA Astrophysics Data System (ADS)

    Levin, Ingeborg; Karstens, Ute

    2007-04-01

    An uncertainty estimate of a purely observational approach to derive hourly regional fossil fuel CO2 offsets (ΔCO2(foss)) at continental CO2 monitoring sites is presented. Weekly mean 14C-based fossil fuel CO2 mixing ratios and corresponding regional CO offsets (ΔCO) are proposed to determine weekly mean ΔCO/ΔCO2(foss) ratios in order to derive hourly ΔCO2(foss) mixing ratios from hourly ΔCO measurements. Respective regional model estimates of CO and CO2(foss) are applied to test this approach and obtain root mean square errors of the correspondingly determined regional hourly fossil fuel CO2 component. The method is further validated with campaign-based observations in Heidelberg. The uncertainty of the proposed method turns out to increase with decreasing fossil fuel CO2 fraction ranging from about 15% up to 40% for continental Europe. Together with the uncertainty of the ΔCO/ΔCO2(foss) ratio, which is determined by the precision of the 14CO2 measurement, this method is still more accurate and precise than any model-based approach.

  10. Atmospheric Verification of Point Source Fossil Fuel CO2 Emissions

    NASA Astrophysics Data System (ADS)

    Turnbull, J. C.; Keller, E. D.; Norris, M. W.; Wiltshire, R.; Baisden, W. T.; Brailsford, G. W.; Bromley, T.

    2015-12-01

    Large point sources (electricity generation and large-scale industry) make up roughly one third of all fossil fuel CO2 (CO2ff) emissions. Currently, these emissions are determined from self-reported inventory data, and sometimes from smokestack emissions monitoring, and the uncertainty in emissions from individual power plants is about 20%. We examine the utility of atmospheric 14C measurements combined with atmospheric transport modelling as a tool for independently quantifying point source CO2ff emissions, to both improve the accuracy of the reported emissions and for verification as we move towards a regulatory environment. We use the Kapuni Gas Treatment Facility as a test case. It is located in rural New Zealand with no other significant fossil fuel CO2 sources nearby, and emits CO2ff at ~0.1 Tg carbon per year. We use several different sampling methods to determine the 14C and hence the CO2ff content downwind of the emission source: grab flask samples of whole air; absorption of CO2 into sodium hydroxide integrated over many hours; and plant material which faithfully records the 14C content of assimilated CO2. We use a plume dispersion model to compare the reported emissions with our observed CO2ff mole fractions. We show that the short-term variability in plume dispersion makes it difficult to interpret the grab flask sample results, whereas the variability is averaged out in the integrated samples and we obtain excellent agreement between the reported and observed emissions, indicating that the 14C method can reliably be used to evaluated point source emissions.

  11. Monitoring of near surface CO2

    NASA Astrophysics Data System (ADS)

    Faber, E.; Möller, I.; Teschner, M.; Poggenburg, J.; Spickenbom, K.; Schulz, H. J.

    2009-04-01

    Monitoring of near surface CO2 ECKHARD FABER1, INGO MÖLLER1, MANFRED TESCHNER1, JÜRGEN POGGENBURG1, KAI SPICKENBOM1, HANS-MARTIN SCHULZ1,2 1Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Stilleweg 2, D-30655 Hannover, e.faber@bgr.de 2present adress: GeoForschungsZentrum Potsdam (GFZ), Telegrafenberg, D-14473 Potsdam Underground gas storage and sequestration of carbon dioxide is one of the methods to reduce the input of antropogenic CO2 into the atmosphere and its greenhouse effect. Storage of CO2 is planned in depleted reservoirs, in aquifers and in salt caverns. Storage sites must have very small leakage rates to safely store the CO2 for centuries. Thus, a careful investigation and site selection is crucial. However, any leakage of CO2 to the surface is potentially dangerous for humans and environment. Therefore, instruments and systems for the detection of any CO2 escaping the storage sites and reaching the atmosphere have to be developed. Systems to monitor gases in deep wells, groundwater and surface sediments for leaking CO2 are developed, tested and are contnuously improved. Our group is mainly analysing CO2 in shallow (down to 3 m) soil samples using automatically operating monitoring systems. The systems are equipped with sensors to measure CO2 (and other gases) concentrations and other environmental parameters (atmospheric pressure, ambient and soil temperatures, etc.). Data are measured in short intervals (minute to subminute), are stored locally and are transferred by telemetrical systems into the BGR laboratory (Weinlich et al., 2006). In addition to soil gases monitoring systems technical equipment is available for continuous underwater gas flow measurements. Several of those monitoring systems are installed in different areas like Czech Republic, Austria, Italy and Germany. To detect any leaking gas from a sequestration site after CO2 injection, the naturally existing CO2 concentration (before injection) must be known. Thus, the natural

  12. Carbon monoxide: A quantitative tracer for fossil fuel CO2?

    NASA Astrophysics Data System (ADS)

    Gamnitzer, Ulrike; Karstens, Ute; Kromer, Bernd; Neubert, Rolf E. M.; Meijer, Harro A. J.; Schroeder, Hartwig; Levin, Ingeborg

    2006-11-01

    Carbon monoxide (CO), carbon dioxide (CO2), and radiocarbon (14CO2) measurements have been made in Heidelberg from 2001 to 2004 in order to determine the regional fossil fuel CO2 component and to investigate the application of CO as a quantitative tracer for fossil fuel CO2 (CO2(foss)). The observations were compared with model estimates simulated with the regional transport model REMO at 0.5° × 0.5° resolution in Europe for 2002. These estimates are based on two available emissions inventories for CO and CO2(foss) and simplified atmospheric chemistry of CO. Both emissions inventories appear to overestimate fossil fuel emissions in the Heidelberg catchment area, in particular in summer and autumn by up to a factor of 2. Nevertheless, during meteorological conditions with high local source influence the CO/CO2(foss) emission ratios compared well with the observed atmospheric CO/CO2(foss) ratios. For a larger catchment area of several 100 km the observed CO/CO2(foss) ratio compared within better than 25% with the ratios derived from model simulations that take the transport from the sites of emission to the measurement station into account. Non-fossil-fuel CO emissions, production by volatile organic compounds, and oxidation, as well as soil uptake, turned out to add significant uncertainty to the application of CO as a quantitative fossil fuel CO2 surrogate tracer, so that 14CO2 measurements seem to be indispensable for reliable estimates of fossil fuel CO2 over the European continent.

  13. Process monitoring during CO2 laser cutting

    NASA Astrophysics Data System (ADS)

    Jorgensen, Henning; Olsen, Flemming O.

    1991-05-01

    On-line process control equipment for CO2 laser cutting is not available for industrial applications today. The majority of the industrial cutting machines are regulated off-line by highly-educated staffs. The quality inspection of the samples often is visual, and referred to different quality scales. Due to this lack of automatization, potential laser users hesitate to implement the cutting method and hereby to benefit from the advantages offered by the method. The first step toward an automatization of the process is development of a process monitoring system, and the investigation described in this paper is concentrated in the area of on-line quality detection during CO2 laser cutting. The method is based on detection of the emitted light from the cut front by photo diodes. The detection is made co-axial with the laser beam to assure independence of the chosen processing direction. ZnSe mirrors have been placed in the beam path, reflecting the laser beam but transmitting the visible light emitted from the process. Cut series of 2, 6 and 8 mm mild steel have been performed. Fourier Analyses and statistical analyses of the signals have been undertaken, and from these analyses it is possible to estimate the surface roughness in the cut kerf, dross attachment at the backside of the work piece and the penetration of the laser beam.

  14. Oceanic Uptake of Fossil Fuel CO2: Carbon-13 Evidence.

    PubMed

    Quay, P D; Tilbrook, B; Wong, C S

    1992-04-03

    The delta(13)C value of the dissolved inorganic carbon in the surface waters of the Pacific Ocean has decreased by about 0.4 per mil between 1970 and 1990. This decrease has resulted from the uptake of atmospheric CO(2) derived from fossil fuel combustion and deforestation. The net amounts of CO(2) taken up by the oceans and released from the biosphere between 1970 and 1990 have been determined from the changes in three measured values: the concentration of atmospheric CO(2), the delta(13)C of atmospheric CO(2) and the delta(13)C value of dissolved inorganic carbon in the ocean. The calculated average net oceanic CO(2) uptake is 2.1 gigatons of carbon per year. This amount implies that the ocean is the dominant net sink for anthropogenically produced CO(2) and that there has been no significant net CO(2) released from the biosphere during the last 20 years.

  15. Space/time explicit Hestia version 2.0 fossil fuel CO2 emissions for the Los Angeles Basin: comparison to atmospheric monitoring, emission drivers, and policy implications

    NASA Astrophysics Data System (ADS)

    Gurney, K. R.; Liang, J.; Patarasuk, R.; O'Keeffe, D.; Newman, S.; Rao, P.; Hutchins, M.; Huang, J.

    2016-12-01

    The Los Angeles Basin represents one of the largest metropolitan areas in the United States and is home to the Megacity Carbon Project, a multi-institutional effort led by NASA JPL to understand the total carbon budget of the Los Angeles Basin. A key component of that effort is the Hestia bottom-up fossil fuel CO2 emissions data product, which quantifies FFCO2 every hour to the spatial scale of individual buildings and road segments. This data product has undergone considerable revision in the last year and the version 2.0 data product is now complete covering the 2011-2014 time period. In this presentation, we highlight the advances in the Hestia version 2.0 including the improvements to onroad, building and industrial emissions. We make comparisons to the independently reported GHG reporting program of the EPA and to in-situ atmospheric measurement of CO2 at two monotiring locations in Pasadena and Palos Verdes. We provide an analysis of the socioeconomic drivers of emissions in the building and onroad transportation sectors across the domain highlighting hotspots of emissions and spatially-specific opportunities for reductions.

  16. Grassland Soil and Fossil CO2 Fluxes Monitored Using Continuous CELS Measurements of [CO2] and δ13C

    NASA Astrophysics Data System (ADS)

    Rau, G. H.; McAlexander, W. I.; Burton, E. A.; Dobeck, L.; Spangler, L.

    2009-12-01

    Over an 8 day period, the concentration and δ13C of above-ground CO2 at an experimental C3 grassland site (near Bozeman, MT) were continuously measured in situ using a cavity enhanced laser spectrometer (LGR, model 908-0003). Air was constantly drawn from 13 inlets and sequentially diverted into the analyzer at 150 sec intervals using an automated inlet switching system. These data were used to monitor and quantify the relative abundances of background air, soil, and experimentally introduced, fossil fuel derived CO2. The latter source was continuously vented from the soil subsurface as part of a larger project (ZERT) to simulate and detect a leak from underground CO2 storage. Keeling plots showed that the variations in [CO2] were dominated by the mixing of CO2 from the three sources: background air (δ13C = -8.2o/oo), soil (-27o/oo), and fossil (-56o/oo), forming a wedge of data points characteristic of three-end-member mixing (Fig.). Prior to fossil CO2 injection, a linear Keeling relationship was evident (Fig.). Photosynthetic uptake and fractionation of CO2 contributed only a small amount to the total variations seen, as evident in day-night data comparisons. Soil respiration was more dominant at night, and there were significant, periodic venting events of both soil and fossil CO2. Horizontal and vertical profiles of [CO2] and δ13C allowed estimates of CO2 fluxes from both soil respiration and fossil CO2. This study demonstrates that CELS can be useful in field studies of multiple CO2 sources requiring relatively high temporal and spatial measurement resolution.

  17. Directly converting CO2 into a gasoline fuel

    NASA Astrophysics Data System (ADS)

    Wei, Jian; Ge, Qingjie; Yao, Ruwei; Wen, Zhiyong; Fang, Chuanyan; Guo, Lisheng; Xu, Hengyong; Sun, Jian

    2017-05-01

    The direct production of liquid fuels from CO2 hydrogenation has attracted enormous interest for its significant roles in mitigating CO2 emissions and reducing dependence on petrochemicals. Here we report a highly efficient, stable and multifunctional Na-Fe3O4/HZSM-5 catalyst, which can directly convert CO2 to gasoline-range (C5-C11) hydrocarbons with selectivity up to 78% of all hydrocarbons while only 4% methane at a CO2 conversion of 22% under industrial relevant conditions. It is achieved by a multifunctional catalyst providing three types of active sites (Fe3O4, Fe5C2 and acid sites), which cooperatively catalyse a tandem reaction. More significantly, the appropriate proximity of three types of active sites plays a crucial role in the successive and synergetic catalytic conversion of CO2 to gasoline. The multifunctional catalyst, exhibiting a remarkable stability for 1,000 h on stream, definitely has the potential to be a promising industrial catalyst for CO2 utilization to liquid fuels.

  18. Directly converting CO2 into a gasoline fuel.

    PubMed

    Wei, Jian; Ge, Qingjie; Yao, Ruwei; Wen, Zhiyong; Fang, Chuanyan; Guo, Lisheng; Xu, Hengyong; Sun, Jian

    2017-05-02

    The direct production of liquid fuels from CO2 hydrogenation has attracted enormous interest for its significant roles in mitigating CO2 emissions and reducing dependence on petrochemicals. Here we report a highly efficient, stable and multifunctional Na-Fe3O4/HZSM-5 catalyst, which can directly convert CO2 to gasoline-range (C5-C11) hydrocarbons with selectivity up to 78% of all hydrocarbons while only 4% methane at a CO2 conversion of 22% under industrial relevant conditions. It is achieved by a multifunctional catalyst providing three types of active sites (Fe3O4, Fe5C2 and acid sites), which cooperatively catalyse a tandem reaction. More significantly, the appropriate proximity of three types of active sites plays a crucial role in the successive and synergetic catalytic conversion of CO2 to gasoline. The multifunctional catalyst, exhibiting a remarkable stability for 1,000 h on stream, definitely has the potential to be a promising industrial catalyst for CO2 utilization to liquid fuels.

  19. Monitoring solid oxide CO2 capture sorbents in action.

    PubMed

    Keturakis, Christopher J; Ni, Fan; Spicer, Michelle; Beaver, Michael G; Caram, Hugo S; Wachs, Israel E

    2014-12-01

    The separation, capture, and storage of CO2 , the major greenhouse gas, from industrial gas streams has received considerable attention in recent years because of concerns about environmental effects of increasing CO2 concentration in the atmosphere. An emerging area of research utilizes reversible CO2 sorbents to increase conversion and rate of forward reactions for equilibrium-controlled reactions (sorption-enhanced reactions). Little fundamental information, however, is known about the nature of the sorbent surface sites, sorbent surface-CO2 complexes, and the CO2 adsorption/desorption mechanisms. The present study directly spectroscopically monitors Na2 O/Al2 O3 sorbent-CO2 surface complexes during adsorption/desorption with simultaneous analysis of desorbed CO2 gas, allowing establishment of molecular level structure-sorption relationships between individual surface carbonate complexes and the CO2 working capacity of sorbents at different temperatures.

  20. An Artificial Biomimetic Catalysis Converting CO2 to Green Fuels

    NASA Astrophysics Data System (ADS)

    Li, Caihong; Wang, Zhiming

    2017-09-01

    Researchers devote to design catalytic systems with higher activity, selectivity, and stability ideally based on cheap and earth-abundant elements to reduce CO2 to value-added hydrocarbon fuels under mild conditions driven by visible light. This may offer profound inspirations on that. A bi-functional molecular iron catalyst designed could not only catalyze two-electron reduction from CO2 to CO but also further convert CO to CH4 with a high selectivity of 82% stably over several days.

  1. Production of solar fuels by CO2 plasmolysis

    NASA Astrophysics Data System (ADS)

    Goede, Adelbert P. H.; Bongers, Waldo A.; Graswinckel, Martijn F.; M. C. M van de Sanden, Richard; Leins, Martina; Kopecki, Jochen; Schulz, Andreas; Walker, Mathias

    2014-12-01

    A storage scheme for Renewable Energy (RE) based on the plasmolysis of CO2into CO and O2 has been experimentally investigated, demonstrating high energy efficiency (>50%) combined with high energy density, rapid start-stop and no use of scarce materials. The key parameter controlling energy efficiency has been identified as the reduced electric field. Basic plasma parameters including density and temperature are derived from a simple particle and energy balance model, allowing parameter specification of an upscale 100 kW reactor. With RE powered plasmolysis as the critical element, a CO2 neutral energy system becomes feasible when complemented by effective capture of CO2 at the input and separation of CO from the output gas stream followed by downstream chemical processing into hydrocarbon fuels.

  2. Transport realization of high resolution fossil fuel CO2 emissions in an urban domain

    NASA Astrophysics Data System (ADS)

    Zhou, Y.; Gurney, K. R.

    2010-12-01

    CO2 emissions from fossil fuel combustion are the largest net annual flux of carbon in the earth atmosphere system and energy consumption in urban environments is a major contributor to total fossil fuel CO2 emissions. Understanding how the emissions are transported in space and time, especially in urban environments and resolving contributions from individual sources of fossil-fuel CO2 emissions are an essential component of a complete reliable monitoring, reporting, and verification (MRV) system that are emerging at local, national, and international levels. As grid models are not designed to resolve concentrations on local scales, we tested the transport realization of fossil fuel CO2 emissions using the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) model, a commonly used transport algorithm for small domain air quality studies, in the greater Indianapolis region, USA. A typical 24-hour point, mobile, and area sources fossil fuel CO2 emissions in four seasons (spring, summer, autumn and winter) were processed from hourly emissions data and prepared at 500-meter spatial resolution for the model inputs together with other parameters. The simulation result provides a complete 4-dimensional concentration matrix transported from all sources for the urban domain which can be analyzed in order to isolate individual sources or test sampling strategies for verification at selected time periods. In addition, the urban 4-dimensional concentration matrix can be visualized in a virtual environment, which provides a powerful education and outreach platform for researchers, students, and public.

  3. Sensitivity of simulated CO2 concentration to sub-annual variations in fossil fuel CO2 emissions

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Gurney, K. R.; Rayner, P. J.; Baker, D. F.; Liu, Y.; Asefi-Najafabady, S.

    2014-12-01

    This study presents a sensitivity analysis of the impact of sub-annual fossil fuel CO2 emissions on simulated CO2 concentration using a global tracer transport model. Four sensitivity experiments were conducted to investigate the impact of three cyclic components (diurnal, weekly and monthly) and a complete cyclic component (the combination of the three) by comparing with a temporally "flat" fossil fuel CO2 emissions inventory. A complete exploration of these impacts is quantified at annual, seasonal, weekly and diurnal time scales of the CO2concentration for the surface, vertical profile and column-integral structure. Result shows an annual mean surface concentration difference varying from -1.35 ppm to 0.13 ppm at grid scale for the complete cyclic fossil fuel emissions, which is mainly driven by a large negative diurnal rectification and less positive seasonal rectification. The negative diurnal rectification is up to 1.45 ppm at grid scale and primarily due to the covariation of diurnal fossil fuel CO2 emissions and diurnal variations of vertical mixing. The positive seasonal rectification is up to 0.23 ppm at grid scale which is mainly driven by the monthly fossil fuel CO2emissions coupling with atmospheric transport. Both the diurnal and seasonal rectifier effects are indicated at local-to-regional scales with center at large source regions and extend to neighboring regions in mainly Northern Hemisphere. The diurnal fossil fuel CO2 emissions is found to significantly affect the simulated diurnal CO2 amplitude (up to 9.12 ppm at grid scale), which is primarily contributed by the minima concentration differences around local sunset time. Similarly, large impact on the seasonal CO2 amplitude (up to 6.11 ppm) is found at regional scale for the monthly fossil fuel emissions. An impact of diurnal fossil fuel CO2 emissions on simulated afternoon CO2 concentration is also identified by up to 1.13 ppm at local scales. The study demonstrates a large cyclic fossil fuel

  4. Surface Monitoring of Leakage From Geologic CO2 Sequestration

    NASA Astrophysics Data System (ADS)

    Strazisar, B. R.; Klusman, R. W.; Wells, A. W.

    2003-12-01

    The capture of carbon dioxide (CO2) from large point sources and long term storage in geological formations has received much recent attention as a potential green house gas mitigation option. Among the proposed storage locations are active and depleted oil and natural gas reservoirs, unmineable coal seams, and deep saline aquifers. The success of any candidate storage location greatly depends on its ability to keep CO2 underground for a long period of time. In order to evaluate the success or failure of a CO2 storage operation, it is important to monitor injection sites to detect CO2 released at the surface. The U.S. Department of Energy has placed a high priority on the development of inexpensive, effective methods to measure, monitor, and verify long term sequestration of CO2 in geological sinks. Monitoring the leakage of CO2 is a challenging task, due to the small expected concentrations above a leaking reservoir as well as the relatively large background of CO2 present in the atmosphere. Another complication is the fact that CO2 continually diffuses from the soil into the atmosphere due to plant and microbial respiration. Any leak of CO2 from a reservoir would have to be differentiated from these other processes. In cooperation with the Texas Bureau of Economic Geology at the University of Texas, the National Energy Technology Laboratory is conducting a comprehensive surface monitoring effort at the site of a pilot scale injection project. In this project, approximately 4000 tons of CO2 will be injected into the Frio formation, a deep, non-petroleum bearing saline aquifer. Surface monitoring includes the detection of injected tracer molecules, direct measurement of CO2 soil flux, soil gas analysis, and carbon isotope analysis from soil gas CO2. These measurements, in conjunction with a parallel modeling effort and deep seismic surveys, will provide an accurate measure of the leak rate of CO2 to the surface (or an upper limit of leakage). Such an understanding

  5. High resolution fossil fuel combustion CO2 emission fluxes for the United States.

    PubMed

    Gurney, Kevin R; Mendoza, Daniel L; Zhou, Yuyu; Fischer, Marc L; Miller, Chris C; Geethakumar, Sarath; de la Rue du Can, Stephane

    2009-07-15

    Quantification of fossil fuel CO2 emissions at fine space and time resolution is emerging as a critical need in carbon cycle and climate change research. As atmospheric CO2 measurements expand with the advent of a dedicated remote sensing platform and denser in situ measurements, the ability to close the carbon budget at spatial scales of approximately 100 km2 and daily time scales requires fossil fuel CO2 inventories at commensurate resolution. Additionally, the growing interest in U.S. climate change policy measures are best served by emissions that are tied to the driving processes in space and time. Here we introduce a high resolution data product (the "Vulcan" inventory: www.purdue.edu/eas/carbon/vulcan/) that has quantified fossil fuel CO2 emissions for the contiguous U.S. at spatial scales less than 100 km2 and temporal scales as small as hours. This data product completed for the year 2002, includes detail on combustion technology and 48 fuel types through all sectors of the U.S. economy. The Vulcan inventory is built from the decades of local/regional air pollution monitoring and complements these data with census, traffic, and digital road data sets. The Vulcan inventory shows excellent agreement with national-level Department of Energy inventories, despite the different approach taken by the DOE to quantify U.S. fossil fuel CO2 emissions. Comparison to the global 1degree x 1 degree fossil fuel CO2 inventory, used widely by the carbon cycle and climate change community prior to the construction of the Vulcan inventory, highlights the space/time biases inherent in the population-based approach.

  6. Detection of CO2 leakage by the surface-soil CO2-concentration monitoring (SCM) system in a small scale CO2 release test

    NASA Astrophysics Data System (ADS)

    Chae, Gitak; Yu, Soonyoung; Sung, Ki-Sung; Choi, Byoung-Young; Park, Jinyoung; Han, Raehee; Kim, Jeong-Chan; Park, Kwon Gyu

    2015-04-01

    Monitoring of CO2 release through the ground surface is essential to testify the safety of CO2 storage projects. We conducted a feasibility study of the multi-channel surface-soil CO2-concentration monitoring (SCM) system as a soil CO2 monitoring tool with a small scale injection. In the system, chambers are attached onto the ground surface, and NDIR sensors installed in each chamber detect CO2 in soil gas released through the soil surface. Before injection, the background CO2 concentrations were measured. They showed the distinct diurnal variation, and were positively related with relative humidity, but negatively with temperature. The negative relation of CO2 measurements with temperature and the low CO2 concentrations during the day imply that CO2 depends on respiration. The daily variation of CO2 concentrations was damped with precipitation, which can be explained by dissolution of CO2 and gas release out of pores through the ground surface with recharge. For the injection test, 4.2 kg of CO2 was injected 1 m below the ground for about 30 minutes. In result, CO2 concentrations increased in all five chambers, which were located less than 2.5 m of distance from an injection point. The Chamber 1, which is closest to the injection point, showed the largest increase of CO2 concentrations; while Chamber 2, 3, and 4 showed the peak which is 2 times higher than the average of background CO2. The CO2 concentrations increased back after decreasing from the peak around 4 hours after the injection ended in Chamber 2, 4, and 5, which indicated that CO2 concentrations seem to be recovered to the background around 4 hours after the injection ended. To determine the leakage, the data in Chamber 2 and 5, which had low increase rates in the CO2 injection test, were used for statistical analysis. The result shows that the coefficient of variation (CV) of CO2 measurements for 30 minutes is efficient to determine a leakage signal, with reflecting the abnormal change in CO2

  7. Sensitivity of simulated CO2 concentration to spatial aggregation and temporal structure in fossil fuel CO2 emissions generated by FFDAS

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Gurney, K. R.; Rayner, P. J.; Asefi-Najafabady, S.; Liu, Y.; Razlivanov, I. N.; Coltin, K.; McRobert, A.

    2013-12-01

    Accurate representation of fossil fuel CO2 emissions is becoming increasingly critical to atmospheric CO2 inversions, forward carbon cycle modeling and carbon budget studies. With the advent of remotely sensed CO2 concentration and a growing surface CO2 observing network, mischaracterization of the spatial and temporal structure of fossil fuel CO2 emissions can result in considerable error in quantification of the global carbon cycle and interactions with climate change. Here we present a sensitivity analysis of two key aspects of the new global FFDAS version 2.0 fossil fuel CO2 emissions data product, which represents hourly fossil fuel CO2 emissions across the globe. The first is an investigation into the potential aggregation bias of coastal fossil fuel CO2 emissions when aggregated from the 0.1 degree spatial resolution to coarser grid spacing. The second is an analysis of the impact of diurnal, weekly, and monthly time cycles. For the aggregation analysis, we compare a 'shuffled' coastline fossil fuel CO2 emissions to a non-'shuffled' case and analyze the CO2 concentration differences at ground-based coastal CO2 monitoring locations. For the time sensitivity study, we compare a temporally 'flat' fossil fuel CO2 emissions data product to cases with diurnal, weekly, and monthly time structure. We also compare 'flat' emissions to a data product with all time cycles present. The coastal aggregation bias experiment indicates that annual mean surface CO2 concentration differences between the 'shuffled' and non-'shuffled' simulations vary from -6.60 to +6.54 ppmv at coastline locations in the US, Europe and eastern Asia. Examination of these differences at the hourly timescale shows CO2 concentration percent differences at monitoring sites as large as ~60%. Turning to the time sensitivity study, a comparison of flat emissions to emissions with only a diurnal time cycle, exhibit hourly-mean surface CO2 concentration differences ranging from -1.98 to +7.15 ppmv (-8% to

  8. A leak monitoring method for CO2 storage sites using ratio of ∆CO2:∆O2 at the soil surface

    NASA Astrophysics Data System (ADS)

    Alam, M. M.; Norman, A. L.; Layzell, D. B.; Amiri, N.

    2016-12-01

    Carbon Capture and Storage (CCS) technology has a high potential for reducing carbon emission at large scales. However, the success of CCS projects vastly depends on the continuous monitoring of injected CO2 and ensuring it remains below ground. The technology currently available for monitoring sites are mainly adopted from disciplines which are effective at detecting high volume leaks but may not be reliable in distinguishing seepage of CO2 from underground and fossil fuel combustion at the surface. We have constructed a numerical model that includes soil characteristics and the bio-geo-chemical dynamics of near surface soils and soil gases. The simulation of our model can predict O2 and CO2 profiles in soil and differential ratios with respect to atmospheric concentrations (∆CO2 and ∆O2), and distinguish CO2 leaks. Experiments on a 1-m soil column have been conducted using dual channel IR and fuel cell analyzers to verify our model predictions. The preliminary results show that measured O2 and CO2 concentrations in near-surface soil layers and the ratio of ∆CO2:∆O2 at the soil surface are in agreement with our model. Based on initial results it is expected that this method of monitoring will able to detect fluxes as small as 2-6µmole/m2/s of CO 2 leakage.

  9. Diffuse CO2 degassing monitoring of Cerro Negro volcano, Nicaragua

    NASA Astrophysics Data System (ADS)

    Hernández, Pedro A.; Alonso, Mar; Ibarra, Martha; Rodríguez, Wesly; Melián, Gladys V.; Saballos, Armando; Barrancos, José; Pérez, Nemesio M.; Álvarez, Julio; Martínez, William

    2017-04-01

    We report the results of fourteen soil CO2 efflux surveys by the closed accumulation chamber method at Cerro Negro volcano, Nicaragua. The surveys were undertaken from 1999 to 2016 to constrain the diffuse CO2 emission from this volcano and to evaluate the spatial and temporal variations of CO2 degassing rate in relation to the eruptive cycle. Cerro Negro is an active basaltic volcano belonging to the active Central American Volcanic Arc which includes a 1,100 Km long chain of 41 active volcanoes from Guatemala to Panama. Cerro Negro first erupted in 1850 and has experienced 21 eruptive eruptions with inter eruptive average periods between 7 and 9 years. Since the last eruption occurred on 5 August 1999, with erupted lava flows and ash clouds together with gas emissions, a collaborative research program between INETER and ITER/INVOLCAN has been established for monitoring diffuse CO2 emissions from this volcano. The first survey carried out at Cerro Negro was in December 1999, just 3 months after the 1999 eruption, with a total diffuse CO2 emission output estimated on 1,869 ± 197 td-1. The second survey carried out in March 2003, three years after the eruption, yielded a value of 432 ± 54 td-1. Both values that can be considered within the post-eruptive phase. The last survey performed at Cerro Negro was in November 2016, with an estimated diffuse CO2 emission of 63 ± 14 tṡd-1and soil CO2 efflux values ranging from non-detectable (˜0.5 g m-2 d-1) up to 7264 g m-2 d-1. The long-term record of diffuse CO2 emissions at Cerro Negro shows small temporal variations in CO2 emissions with a peak in 2004 (256 ± 26 td-1) followed by a peak in seismicity. Except this value, the rest of estimated values can be considered within the inter-eruptive phase, period during which a decreasing trend on the total diffuse CO2 output has been observed, with estimates between 10 and 83 tṡd-1. Regarding to the spatial distribution of diffuse CO2 values, most of relatively high CO2

  10. Spatial Relationships of Sector-Specific Fossil-fuel CO2 Emissions in the United States

    SciTech Connect

    Zhou, Yuyu; Gurney, Kevin R.

    2011-07-01

    Quantification of the spatial distribution of sector-specific fossil fuel CO2 emissions provides strategic information to public and private decision-makers on climate change mitigation options and can provide critical constraints to carbon budget studies being performed at the national to urban scales. This study analyzes the spatial distribution and spatial drivers of total and sectoral fossil fuel CO2 emissions at the state and county levels in the United States. The spatial patterns of absolute versus per capita fossil fuel CO2 emissions differ substantially and these differences are sector-specific. Area-based sources such as those in the residential and commercial sectors are driven by a combination of population and surface temperature with per capita emissions largest in the northern latitudes and continental interior. Emission sources associated with large individual manufacturing or electricity producing facilities are heterogeneously distributed in both absolute and per capita metrics. The relationship between surface temperature and sectoral emissions suggests that the increased electricity consumption due to space cooling requirements under a warmer climate may outweigh the savings generated by lessened space heating. Spatial cluster analysis of fossil fuel CO2 emissions confirms that counties with high (low) CO2 emissions tend to be clustered close to other counties with high (low) CO2 emissions and some of the spatial clustering extends to multi-state spatial domains. This is particularly true for the residential and transportation sectors, suggesting that emissions mitigation policy might best be approached from the regional or multi-state perspective. Our findings underscore the potential for geographically focused, sector-specific emissions mitigation strategies and the importance of accurate spatial distribution of emitting sources when combined with atmospheric monitoring via aircraft, satellite and in situ measurements. Keywords: Fossil-fuel

  11. Detecting fossil fuel emissions patterns from subcontinental regions using North American in situ CO2 measurements.

    PubMed

    Shiga, Yoichi P; Michalak, Anna M; Gourdji, Sharon M; Mueller, Kim L; Yadav, Vineet

    2014-06-28

    The ability to monitor fossil fuel carbon dioxide (FFCO2) emissions from subcontinental regions using atmospheric CO2 observations remains an important but unrealized goal. Here we explore a necessary but not sufficient component of this goal, namely, the basic question of the detectability of FFCO2 emissions from subcontinental regions. Detectability is evaluated by examining the degree to which FFCO2 emissions patterns from specific regions are needed to explain the variability observed in high-frequency atmospheric CO2 observations. Analyses using a CO2 monitoring network of 35 continuous measurement towers over North America show that FFCO2 emissions are difficult to detect during nonwinter months. We find that the compounding effects of the seasonality of atmospheric transport patterns and the biospheric CO2 flux signal dramatically hamper the detectability of FFCO2 emissions. Results from several synthetic data case studies highlight the need for advancements in data coverage and transport model accuracy if the goal of atmospheric measurement-based FFCO2 emissions detection and estimation is to be achieved beyond urban scales. Poor detectability of fossil fuel CO2 emissions from subcontinental regionsDetectability assessed via attribution of emissions patterns in atmospheric dataLoss in detectability due to transport modeling errors and biospheric signal.

  12. High-Resolution Isotopic Monitoring of Cave Air CO2

    NASA Astrophysics Data System (ADS)

    Töchterle, Paul; Dublyansky, Yuri; Mandic, Magda; Stöbener, Nils; Jost, Hj; Spötl, Christoph

    2016-04-01

    This study aims at characterising the ventilation patterns in Spannagel Cave, a high-alpine cave system in the Zillertal Alps, Austria. A Thermo Scientific Delta Ray Isotope Ratio Infrared Spectrometer was installed in a chamber ca. 100 m behind the cave entrance to monitor pCO2 and δ13C and δ18O of CO2 at high temporal resolution (up to 1 s). The air temperature was independently monitored inside and outside the cave. This study aims at characterising the ventilation patterns in Spannagel Cave, a high-alpine cave system in the Zillertal Alps, Austria. A Thermo Scientific Delta Ray Isotope Ratio Infrared Spectrometer was installed in a chamber ca. 100 m behind the cave entrance to monitor pCO2 and δ13C and δ18O of CO2 at high temporal resolution (up to 1s). The air temperature was independently monitored inside and outside the cave. The data show two distinct patterns in terms of CO2 concentration and its isotopic composition, which are closely coupled with the temperature difference between the cave interior and the outside atmosphere. This gradient controls the direction of air flow in the cave on a seasonal to synoptic timescale (chimney-type ventilation). The summer circulation is characterised by CO2 closely resembling atmospheric values (pCO2 = 399 ± 12 ppm, δ13C = -8.5 ± 0.7 permil, δ18O = 8.1 ± 2.5 permil). The winter circulation mode features generally higher CO2 concentrations and lower isotopic compositions (pCO2 = 409 ± 14 ppm, δ13C = -10.1 ± 0.7 permil, δ18O = 2.3 ± 1.5 permil). The high temporal resolution of stable isotope data allows tracking cave air ventilation changes, including transient and short-lived ones. Moreover, the data make it possible to address concomitant geochemical processes, such as the input of atmospheric CO2 and the degassing of CO2 from seepage water. These processes would not be possible to quantify without the new generation of laser-based isotope ratio instruments represented by the Delta Ray.

  13. Discriminating and continuous measurement of photosynthesis and respiration by monitoring 13CO2 and 12CO2 as tracers.

    PubMed

    Nishi, I; Futami, J; Ma, P; Ishii, H; Takakura, T; Goto, E

    1996-12-01

    The simultaneous and discriminative measurement of the photosynthesis and the respiration of the plant was attained by simultaneous monitoring of 13CO2 and 12CO2 by artificial control of 13CO2 abundance of ambient air. The principle of the measurement is based on the following physiological processes. 6CO2 + 12H2O --> C6H12O6 + 6O2 + 6H2O, 6(13C)O2 + 12H2O --> (13C6)H12O6 + 6O2 + 6H2O, 6CO2 + 12H2(18O) --> C6H12O6 + 6(18O)18O + 6H20. Assuming that respiratory consumption of the new born carbon substrate fixed by photosynthesis is negligible during the measurement, the photosynthetic CO2 consumption VPCO2 and the respiratory CO2 production VRCO2 are measured according to the estimation (1) or (2), (1) for closed method, VPCO2 = k(V0 - V t)¿ F13CO2 + (F12CO2/F13CO2)F13CO2 ¿, VRCO2 = k(V0 - V t)¿ F12CO2 - (F12CO2/F13CO2)F13CO2 ¿, (2) for open method, VPCO2 = kVE ¿ (FI13CO2 - FE13CO2) + (F12CO2/F13CO2)(FI13CO2 - FE13CO2) ¿, VRCO2 = kVE ¿ (FI12CO2 - FE12CO2) - (F12CO2/F13CO2)(FI13CO2 - FE13CO2) ¿ where V0 is initial volume of growth chamber including attached flexible bag, FICO2 is the inlet or initial gas concentration of CO2 and FECO2 is the ambient gas concentration of CO2 in the chamber, V and VE are the sampling rate of mass spectrometer and the ventilation rate of the growth chamber respectively, k is the STPD conversion factor = ¿273(PB-PH2O)/760(273+tE)¿, tE(degrees C) is the ambient gas temperature. In the closed method, the gas container of the growth chamber is circulated, resulting FECO2 is varied according to the balance of consumption and production of CO2, while in the open method VE is controlled to keep FECO2 at a constant value. Both (1) and (2) methods were examined and evaluated on the measurements of komatsuna and maize.

  14. Radiocarbon observations in atmospheric CO2: determining fossil fuel CO2 over Europe using Jungfraujoch observations as background.

    PubMed

    Levin, Ingeborg; Hammer, Samuel; Kromer, Bernd; Meinhardt, Frank

    2008-03-01

    Monthly mean 14CO2 observations at two regional stations in Germany (Schauinsland observatory, Black Forest, and Heidelberg, upper Rhine valley) are compared with free tropospheric background measurements at the High Alpine Research Station Jungfraujoch (Swiss Alps) to estimate the regional fossil fuel CO2 surplus at the regional stations. The long-term mean fossil fuel CO2 surplus at Schauinsland is 1.31+/-0.09 ppm while it is 10.96+/-0.20 ppm in Heidelberg. No significant trend is observed at both sites over the last 20 years. Strong seasonal variations of the fossil fuel CO2 offsets indicate a strong seasonality of emissions but also of atmospheric dilution of ground level emissions by vertical mixing.

  15. Monitoring Atmospheric CO2 From Space: Challenge & Approach

    NASA Technical Reports Server (NTRS)

    Lin, Bing; Harrison, F. Wallace; Nehrir, Amin; Browell, Edward; Dobler, Jeremy; Campbell, Joel; Meadows, Byron; Obland, Michael; Kooi, Susan; Fan, Tai-Fang; Ismail, Syed

    2015-01-01

    Atmospheric CO2 is the key radiative forcing for the Earth's climate and may contribute a major part of the Earth's warming during the past 150 years. Advanced knowledge on the CO2 distributions and changes can lead considerable model improvements in predictions of the Earth's future climate. Large uncertainties in the predictions have been found for decades owing to limited CO2 observations. To obtain precise measurements of atmospheric CO2, certain challenges have to be overcome. For an example, global annual means of the CO2 are rather stable, but, have a very small increasing trend that is significant for multi-decadal long-term climate. At short time scales (a second to a few hours), regional and subcontinental gradients in the CO2 concentration are very small and only in an order of a few parts per million (ppm) compared to the mean atmospheric CO2 concentration of about 400 ppm, which requires atmospheric CO2 space monitoring systems with extremely high accuracy and precision (about 0.5 ppm or 0.125%) in spatiotemporal scales around 75 km and 10-s. It also requires a decadal-scale system stability. Furthermore, rapid changes in high latitude environments such as melting ice, snow and frozen soil, persistent thin cirrus clouds in Amazon and other tropical areas, and harsh weather conditions over Southern Ocean all increase difficulties in satellite atmospheric CO2 observations. Space lidar approaches using Integrated Path Differential Absorption (IPDA) technique are considered to be capable of obtaining precise CO2 measurements and, thus, have been proposed by various studies including the 2007 Decadal Survey (DS) of the U.S. National Research Council. This study considers to use the Intensity-Modulated Continuous-Wave (IM-CW) lidar to monitor global atmospheric CO2 distribution and variability from space. Development and demonstration of space lidar for atmospheric CO2 measurements have been made through joint adventure of NASA Langley Research Center and

  16. Fuel from Bacteria, CO2, Water, and Solar Energy: Engineering a Bacterial Reverse Fuel Cell

    SciTech Connect

    2010-07-01

    Electrofuels Project: Harvard is engineering a self-contained, scalable Electrofuels production system that can directly generate liquid fuels from bacteria, carbon dioxide (CO2), water, and sunlight. Harvard is genetically engineering bacteria called Shewanella, so the bacteria can sit directly on electrical conductors and absorb electrical current. This current, which is powered by solar panels, gives the bacteria the energy they need to process CO2 into liquid fuels. The Harvard team pumps this CO2 into the system, in addition to water and other nutrients needed to grow the bacteria. Harvard is also engineering the bacteria to produce fuel molecules that have properties similar to gasoline or diesel fuel—making them easier to incorporate into the existing fuel infrastructure. These molecules are designed to spontaneously separate from the water-based culture that the bacteria live in and to be used directly as fuel without further chemical processing once they’re pumped out of the tank.

  17. Separation of biospheric and fossil fuel fluxes of CO2 by atmospheric inversion of CO2 and 14CO2 measurements: Observation System Simulations

    NASA Astrophysics Data System (ADS)

    Basu, Sourish; Bharat Miller, John; Lehman, Scott

    2016-05-01

    National annual total CO2 emissions from combustion of fossil fuels are likely known to within 5-10 % for most developed countries. However, uncertainties are inevitably larger (by unknown amounts) for emission estimates at regional and monthly scales, or for developing countries. Given recent international efforts to establish emission reduction targets, independent determination and verification of regional and national scale fossil fuel CO2 emissions are likely to become increasingly important. Here, we take advantage of the fact that precise measurements of 14C in CO2 provide a largely unbiased tracer for recently added fossil-fuel-derived CO2 in the atmosphere and present an atmospheric inversion technique to jointly assimilate observations of CO2 and 14CO2 in order to simultaneously estimate fossil fuel emissions and biospheric exchange fluxes of CO2. Using this method in a set of Observation System Simulation Experiments (OSSEs), we show that given the coverage of 14CO2 measurements available in 2010 (969 over North America, 1063 globally), we can recover the US national total fossil fuel emission to better than 1 % for the year and to within 5 % for most months. Increasing the number of 14CO2 observations to ˜ 5000 per year over North America, as recently recommended by the National Academy of Science (NAS) (Pacala et al., 2010), we recover monthly emissions to within 5 % for all months for the US as a whole and also for smaller, highly emissive regions over which the specified data coverage is relatively dense, such as for the New England states or the NY-NJ-PA tri-state area. This result suggests that, given continued improvement in state-of-the art transport models, a measurement program similar in scale to that recommended by the NAS can provide for independent verification of bottom-up inventories of fossil fuel CO2 at the regional and national scale. In addition, we show that the dual tracer inversion framework can detect and minimize biases in

  18. Spatial relationships of sector-specific fossil fuel CO2 emissions in the United States

    NASA Astrophysics Data System (ADS)

    Zhou, Yuyu; Gurney, Kevin Robert

    2011-09-01

    Quantification of the spatial distribution of sector-specific fossil fuel CO2 emissions provides strategic information to public and private decision makers on climate change mitigation options and can provide critical constraints to carbon budget studies being performed at the national to urban scales. This study analyzes the spatial distribution and spatial drivers of total and sectoral fossil fuel CO2 emissions at the state and county levels in the United States. The spatial patterns of absolute versus per capita fossil fuel CO2 emissions differ substantially and these differences are sector-specific. Area-based sources such as those in the residential and commercial sectors are driven by a combination of population and surface temperature with per capita emissions largest in the northern latitudes and continental interior. Emission sources associated with large individual manufacturing or electricity producing facilities are heterogeneously distributed in both absolute and per capita metrics. The relationship between surface temperature and sectoral emissions suggests that the increased electricity consumption due to space cooling requirements under a warmer climate may outweigh the savings generated by lessened space heating. Spatial cluster analysis of fossil fuel CO2 emissions confirms that counties with high (low) CO2 emissions tend to be clustered close to other counties with high (low) CO2 emissions and some of the spatial clustering extends to multistate spatial domains. This is particularly true for the residential and transportation sectors, suggesting that emissions mitigation policy might best be approached from the regional or multistate perspective. Our findings underscore the potential for geographically focused, sector-specific emissions mitigation strategies and the importance of accurate spatial distribution of emitting sources when combined with atmospheric monitoring via aircraft, satellite and in situ measurements.

  19. Characterizing CO2 storage reservoir for above-zone monitoring

    NASA Astrophysics Data System (ADS)

    Zahid, K. M.; Hovorka, S. D.

    2011-12-01

    CO2 enhanced oil recovery (EOR) provides an excellent opportunity for commercial sequestration of anthropogenic CO2. Fluvial, strand plain, and deltaic sandstones of Oligocene and Miocene formations that extend across the Gulf Coast Basin were prolific oil producers for many decades and are also considered to be effective reservoirs for large scale carbon storage. A deep-seated salt dome, faulted anticlinal structure from Gulf coastal region is currently under investigation to develop a monitoring, verification, and accounting (MVA) plan as coordinated with commercial surveillance of an EOR site for injecting large volume (>1 Million ton/year) of CO2. Geophysical logs have been used to characterize the injection zone reservoir and overburden. One novel MVA element in design is above-zone pressure and geochemical monitoring for out-of-zone migration. Initial characterization with wireline logs demonstrates the extent and areal continuity of reservoir sands and geometries of faults that cut the reservoir. To develop the monitoring plan, we focus characterization on several elements: (1) input data for quick-look dynamic model of the extent of CO2 plume and amount and extent of accompanying pressure elevation, (2) characterization of the zones above the top-reservoir seal for above-zone pressure monitoring, and (3) intersection of faults with well-bores in intervals above the top-reservoir seal for thermal monitoring. Other uncertainties addressed during characterization are the upper extent of faults and juxtaposition of layers to assess the potential for cross-fault fluid migration. Such detail characterization will allow realistic assessment of the sensitivity of monitoring techniques such as temperature logging for tracking up-fault fluid migration and pressure change for out-of zone fluid migration. Successful use of such geophysical techniques for MVA based on uniting elements of existing regulatory monitoring expectations with commercial best practices will be

  20. 40 CFR 75.13 - Specific provisions for monitoring CO2 emissions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Specific provisions for monitoring CO2... monitoring CO2 emissions. (a) CO 2 continuous emission monitoring system. If the owner or operator chooses to... operating requirements in § 75.10 for a CO2 continuous emission monitoring system and flow monitoring system...

  1. Quantifying fossil fuel CO2 from continuous measurements of APO: a novel approach

    NASA Astrophysics Data System (ADS)

    Pickers, Penelope; Manning, Andrew C.; Forster, Grant L.; van der Laan, Sander; Wilson, Phil A.; Wenger, Angelina; Meijer, Harro A. J.; Oram, David E.; Sturges, William T.

    2016-04-01

    Using atmospheric measurements to accurately quantify CO2 emissions from fossil fuel sources requires the separation of biospheric and anthropogenic CO2 fluxes. The ability to quantify the fossil fuel component of CO2 (ffCO2) from atmospheric measurements enables more accurate 'top-down' verification of CO2 emissions inventories, which frequently have large uncertainty. Typically, ffCO2 is quantified (in ppm units) from discrete atmospheric measurements of Δ14CO2, combined with higher resolution atmospheric CO measurements, and with knowledge of CO:ffCO2 ratios. In the United Kingdom (UK), however, measurements of Δ14CO2 are often significantly biased by nuclear power plant influences, which limit the use of this approach. We present a novel approach for quantifying ffCO2 using measurements of APO (Atmospheric Potential Oxygen; a tracer derived from concurrent measurements of CO2 and O2) from two measurement sites in Norfolk, UK. Our approach is similar to that used for quantifying ffCO2 from CO measurements (ffCO2(CO)), whereby ffCO2(APO) = (APOmeas - APObg)/RAPO, where (APOmeas - APObg) is the APO deviation from the background, and RAPO is the APO:CO2 combustion ratio for fossil fuel. Time varying values of RAPO are calculated from the global gridded COFFEE (CO2 release and Oxygen uptake from Fossil Fuel Emission Estimate) dataset, combined with NAME (Numerical Atmospheric-dispersion Modelling Environment) transport model footprints. We compare our ffCO2(APO) results to results obtained using the ffCO2(CO) method, using CO:CO2 fossil fuel emission ratios (RCO) from the EDGAR (Emission Database for Global Atmospheric Research) database. We find that the APO ffCO2 quantification method is more precise than the CO method, owing primarily to a smaller range of possible APO:CO2 fossil fuel emission ratios, compared to the CO:CO2 emission ratio range. Using a long-term dataset of atmospheric O2, CO2, CO and Δ14CO2 from Lutjewad, The Netherlands, we examine the

  2. Plasmolysis for efficient CO2 -to-fuel conversion

    NASA Astrophysics Data System (ADS)

    van Rooij, Gerard

    2015-09-01

    The strong non-equilibrium conditions provided by the plasma phase offer the opportunity to beat traditional thermal process energy efficiencies via preferential excitation of molecular vibrational modes. It is therefore a promising option for creating artificial solar fuels from CO2as raw material using (intermittently available) sustainable energy surpluses, which can easily be deployed within the present infrastructure for conventional fossil fuels. In this presentation, a common microwave reactor approach is evaluated experimentally with Rayleigh scattering and Fourier transform infrared spectroscopy to assess gas temperatures and conversion degrees, respectively. The results are interpreted on basis of estimates of the plasma dynamics obtained with electron energy distribution functions calculated with a Boltzmann solver. It indicates that the intrinsic electron energies are higher than is favourable for preferential vibrational excitation due to dissociative excitation, which causes thermodynamic equilibrium chemistry still to dominate the initial experiments. Novel reactor approaches are proposed to tailor the plasma dynamics to achieve the non-equilibrium in which vibrational excitation is dominant. In collaboration with Dirk van den Bekerom, Niek den Harder, Teofil Minea, Dutch Institute For Fundamental Energy Research, Eindhoven, Netherlands; Gield Berden, Institute for Molecules and Materials, FELIX facility, Radboud University, Nijmegen, Netherlands; Richard Engeln, Applied Physics, Plasma en Materials Processing, Eindhoven University of Technology; and Waldo Bongers, Martijn Graswinckel, Erwin Zoethout, Richard van de Sanden, Dutch Institute For Fundamental Energy Research, Eindhoven, Netherlands.

  3. Estimation of fossil-fuel CO2 emissions using satellite measurements of "proxy" species

    NASA Astrophysics Data System (ADS)

    Konovalov, Igor B.; Berezin, Evgeny V.; Ciais, Philippe; Broquet, Grégoire; Zhuravlev, Ruslan V.; Janssens-Maenhout, Greet

    2016-11-01

    Fossil-fuel (FF) burning releases carbon dioxide (CO2) together with many other chemical species, some of which, such as nitrogen dioxide (NO2) and carbon monoxide (CO), are routinely monitored from space. This study examines the feasibility of estimation of FF CO2 emissions from large industrial regions by using NO2 and CO column retrievals from satellite measurements in combination with simulations by a mesoscale chemistry transport model (CTM). To this end, an inverse modeling method is developed that allows estimating FF CO2 emissions from different sectors of the economy, as well as the total CO2 emissions, in a given region. The key steps of the method are (1) inferring "top-down" estimates of the regional budget of anthropogenic NOx and CO emissions from satellite measurements of proxy species (NO2 and CO in the case considered) without using formal a priori constraints on these budgets, (2) the application of emission factors (the NOx-to-CO2 and CO-to-CO2 emission ratios in each sector) that relate FF CO2 emissions to the proxy species emissions and are evaluated by using data of "bottom-up" emission inventories, and (3) cross-validation and optimal combination of the estimates of CO2 emission budgets derived from measurements of the different proxy species. Uncertainties in the top-down estimates of the NOx and CO emissions are evaluated and systematic differences between the measured and simulated data are taken into account by using original robust techniques validated with synthetic data. To examine the potential of the method, it was applied to the budget of emissions for a western European region including 12 countries by using NO2 and CO column amounts retrieved from, respectively, the OMI and IASI satellite measurements and simulated by the CHIMERE mesoscale CTM, along with the emission conversion factors based on the EDGAR v4.2 emission inventory. The analysis was focused on evaluation of the uncertainty levels for the top-down NOx and CO emission

  4. Natural analogue study of CO2 storage monitoring using probability statistics of CO2-rich groundwater chemistry

    NASA Astrophysics Data System (ADS)

    Kim, K. K.; Hamm, S. Y.; Kim, S. O.; Yun, S. T.

    2016-12-01

    For confronting global climate change, carbon capture and storage (CCS) is one of several very useful strategies as using capture of greenhouse gases like CO2 spewed from stacks and then isolation of the gases in underground geologic storage. CO2-rich groundwater could be produced by CO2 dissolution into fresh groundwater around a CO2 storage site. As consequence, natural analogue studies related to geologic storage provide insights into future geologic CO2 storage sites as well as can provide crucial information on the safety and security of geologic sequestration, the long-term impact of CO2 storage on the environment, and field operation and monitoring that could be implemented for geologic sequestration. In this study, we developed CO2 leakage monitoring method using probability density function (PDF) by characterizing naturally occurring CO2-rich groundwater. For the study, we used existing data of CO2-rich groundwaters in different geological regions (Gangwondo, Gyeongsangdo, and Choongchungdo provinces) in South Korea. Using PDF method and QI (quantitative index), we executed qualitative and quantitative comparisons among local areas and chemical constituents. Geochemical properties of groundwater with/without CO2 as the PDF forms proved that pH, EC, TDS, HCO3-, Ca2+, Mg2+, and SiO2 were effective monitoring parameters for carbonated groundwater in the case of CO2leakage from an underground storage site. KEY WORDS: CO2-rich groundwater, CO2 storage site, monitoring parameter, natural analogue, probability density function (PDF), QI_quantitative index Acknowledgement This study was supported by the "Basic Science Research Program through the National Research Foundation of Korea (NRF), which is funded by the Ministry of Education (NRF-2013R1A1A2058186)" and the "R&D Project on Environmental Management of Geologic CO2 Storage" from KEITI (Project number: 2014001810003).

  5. CO, NOx and 13CO2 as tracers for fossil fuel CO2: results from a pilot study in Paris during winter 2010

    NASA Astrophysics Data System (ADS)

    Lopez, M.; Schmidt, M.; Delmotte, M.; Colomb, A.; Gros, V.; Janssen, C.; Lehman, S. J.; Mondelain, D.; Perrussel, O.; Ramonet, M.; Xueref-Remy, I.; Bousquet, P.

    2013-08-01

    Measurements of the mole fraction of the CO2 and its isotopes were performed in Paris during the MEGAPOLI winter campaign (January-February 2010). Radiocarbon (14CO2) measurements were used to identify the relative contributions of 77% CO2 from fossil fuel consumption (CO2ff from liquid and gas combustion) and 23% from biospheric CO2 (CO2 from the use of biofuels and from human and plant respiration: CO2bio). These percentages correspond to average mole fractions of 26.4 ppm and 8.2 ppm for CO2ff and CO2bio, respectively. The 13CO2 analysis indicated that gas and liquid fuel contributed 70% and 30%, respectively, of the CO2 emission from fossil fuel use. Continuous measurements of CO and NOx and the ratios CO/CO2ff and NOx/CO2ff derived from radiocarbon measurements during four days make it possible to estimate the fossil fuel CO2 contribution over the entire campaign. The ratios CO/CO2ff and NOx/CO2ff are functions of air mass origin and exhibited daily ranges of 7.9 to 14.5 ppb ppm-1 and 1.1 to 4.3 ppb ppm-1, respectively. These ratios are consistent with different emission inventories given the uncertainties of the different approaches. By using both tracers to derive the fossil fuel CO2, we observed similar diurnal cycles with two maxima during rush hour traffic.

  6. Monitoring CO2 and CH4 concentrations along an urban-rural transect in London, UK

    NASA Astrophysics Data System (ADS)

    Boon, Alex; Broquet, Gregoire; Clifford, Debbie; Chevallier, Frederic; Butterfield, David

    2013-04-01

    Cities are important sources of carbon dioxide (CO2) and methane (CH4). Anthropogenic CO2 is released in the combustion of fossil fuels for heating, electricity and transport. The major sources of CH4 in city environments are natural gas leakage, landfill sites and transport emissions. Monitoring of urban greenhouse gas concentrations is crucial for cities aiming to reduce emissions through measures such as changes to the transport infrastructure and green planning. We present measurements of CO2 and CH4 concentrations using Cavity Ring-Down Spectroscopy (CRDS) at four sites located in and around London, UK. Two sites were located in the inner city, one in the suburban fringe and the fourth in a rural location close to the city. This study was funded by Astrium Services Ltd as part of a pilot scheme to monitor city-scale GHG emissions and presented a unique opportunity to study changes in greenhouse gas concentrations across an urban to rural 'transect'. The CHIMERE chemistry-transport model is used to estimate CO2 and CH4 concentrations throughout the four month measurement period during the summer of 2012. Comparisons are made between the measured and modelled CO2 and CH4 concentrations and the representativity of the study sites for future urban greenhouse gas monitoring is considered. This study also examines the ability of a variety of measurement and modelling techniques to partition anthropogenic and biogenic CO2 sources.

  7. Development of a mobile and high-precision atmospheric CO2 monitoring station

    NASA Astrophysics Data System (ADS)

    Molnár, M.; Haszpra, L.; Major, I.; Svingor, É.; Veres, M.

    2009-04-01

    Nowadays one of the most burning questions for the science is the rate and the reasons of the recent climate change. Greenhouse gases (GHG), mainly CO2 and CH4 in the atmosphere could affect the climate of our planet. However, the relation between the amount of atmospheric GHG and the climate is complex, full with interactions and feedbacks partly poorly known even by now. The only way to understand the processes, to trace the changes, to develop and validate mathematical models for forecasts is the extensive, high precision, continuous monitoring of the atmosphere. Fossil fuel CO2 emissions are a major component of the European carbon budget. Separation of the fossil fuel signal from the natural biogenic one in the atmosphere is, therefore, a crucial task for quantifying exchange flux of the continental biosphere through atmospheric observations and inverse modelling. An independent method to estimate trace gas emissions is the top-down approach, using atmospheric CO2 concentration measurements combined with simultaneous radiocarbon (14C) observations. As adding fossil fuel CO2 to the atmosphere, therefore, leads not only to an increase in the CO2 content of the atmosphere but also to a decrease in the 14C/12C ratio in atmospheric CO2. The ATOMKI has more than two decade long experience in atmospheric 14CO2 monitoring. As a part of an ongoing research project being carried out in Hungary to investigate the amount and temporal and spatial variations of fossil fuel CO2 in the near surface atmosphere we developed a mobile and high-precision atmospheric CO2 monitoring station. We describe the layout and the operation of the measuring system which is designed for the continuous, unattended monitoring of CO2 mixing ratio in the near surface atmosphere based on an Ultramat 6F (Siemens) infrared gas analyser. In the station one atmospheric 14CO2 sampling unit is also installed which is developed and widely used since more than one decade by ATOMKI. Mixing ratio of CO2 is

  8. Monitoring Exchange of CO2 - A KISS Workshop Report 2009

    NASA Technical Reports Server (NTRS)

    Miller, Charles; Wennberg, Paul

    2009-01-01

    The problem and context: Can top-down estimates of carbon dioxide (CO2) fluxes resolve the anthropogenic emissions of China, India, the United States, and the European Union with an accuracy of +/-10% or better?The workshop "Monitoring Exchange of Carbon Dioxide" was convened at the Keck Institute for Space Studies in Pasadena, California in February 2010 to address this question. The Workshop brought together an international, interdisciplinary group of 24 experts in carbon cycle science, remote sensing, emissions inventory estimation, and inverse modeling. The participants reviewed the potential of space-based and sub-orbital observational and modeling approaches to monitor anthropogenic CO2 emissions in the presence of much larger natural fluxes from the exchange of CO2 between the land, atmosphere, and ocean. This particular challenge was motivated in part by the NRC Report "Verifying Greenhouse Gas Emissions" [Pacala et al., 2010]. This workshop report includes several recommendations for improvements to observing strategies and modeling frameworks for optimal and cost-effective monitoring of carbon exchange

  9. Monitoring Exchange of CO2 - A KISS Workshop Report 2009

    NASA Technical Reports Server (NTRS)

    Miller, Charles; Wennberg, Paul

    2009-01-01

    The problem and context: Can top-down estimates of carbon dioxide (CO2) fluxes resolve the anthropogenic emissions of China, India, the United States, and the European Union with an accuracy of +/-10% or better?The workshop "Monitoring Exchange of Carbon Dioxide" was convened at the Keck Institute for Space Studies in Pasadena, California in February 2010 to address this question. The Workshop brought together an international, interdisciplinary group of 24 experts in carbon cycle science, remote sensing, emissions inventory estimation, and inverse modeling. The participants reviewed the potential of space-based and sub-orbital observational and modeling approaches to monitor anthropogenic CO2 emissions in the presence of much larger natural fluxes from the exchange of CO2 between the land, atmosphere, and ocean. This particular challenge was motivated in part by the NRC Report "Verifying Greenhouse Gas Emissions" [Pacala et al., 2010]. This workshop report includes several recommendations for improvements to observing strategies and modeling frameworks for optimal and cost-effective monitoring of carbon exchange

  10. Monitoring and Modeling CO2 Dynamics in the Vadose Zone near an Abandoned Historic Oil Well: Implications for Detecting CO2 Leakage at Geological CO2 Sequestration Sites

    NASA Astrophysics Data System (ADS)

    Yang, C.; Romanak, K.; Hovorka, S.; Reedy, R. C.; Trevino, R.; Scanlon, B. R.

    2010-12-01

    Soil-gas monitoring is proposed for detecting CO2 leakage at geological CO2 sequestration sites. At the Cranfield oil field, about 25 km east of Natchez, Mississippi, an integrated near-surface monitoring program is being implemented where supercritical CO2 is being injected for enhanced oil recovery (EOR). The purpose of the study is to understand how natural factors may affect soil CO2 monitoring at geologic carbon storage sites. A near-surface observatory, constructed on an engineered well pad near a 1950’s era open pit and plugged and abandoned well, was used to monitor atmospheric parameters such as air temperature, relative humility, barometric pressure, wind speed and direction, solar radiation, and precipitation. Soil temperature, soil CO2 concentrations, water content, and matric potential were also monitored at various depths to a maximum of 5 m in the vadose zone. The integrated monitoring system was installed in September 2009 and continued collecting data each half hour for about 240 days. CO2 concentrations measured at 1.5 m depth are about two times that of atmospheric CO2 concentrations and show daily fluctuations. However, CO2 concentrations measured at 3 m depth decreased from 11% in November 2009 to 9% in January 2010, then gradually increased to 10.5% in June 2010. There should be no CO2 contribution from root respiration because the engineered pad is bare of vegetation. Monitored CO2 in the vadose zone at this site most likely is derived from oxidation of methane with a suspected source related to the 1950’s era plugged and abandoned well. A 1-D numerical model was also used to simulate variably saturated water flow, CO2 transport, CH4 oxidation for understanding mechanisms that dominate CO2 transport at this site. Results of this study suggest that CO2 transport in the vadose zone is very complicated and can be affected by many factors including precipitation, barometric pressure, soil temperature, oxidation of methane, and therefore may

  11. Stable carbon isotopes to monitor the CO2 source mix in the urban environment

    NASA Astrophysics Data System (ADS)

    Vogel, F. R.; Wu, L.; Ramonet, M.; Broquet, G.; Worthy, D. E. J.

    2014-12-01

    Urban areas are said to be responsible for approximately 71% of fossil fuel CO2 emissions while comprising only two percent of the land area [IEA, 2008]. This limited spatial expansion could facility a monitoring of anthropogenic GHGs from atmospheric observations. As major sources of emissions, cities also have a huge potential to drive emissions reductions. To effectively manage emissions, cities must however, first establish techniques to validate their reported emission statistics. A pilot study which includes continues 13CO2 data from calibrated cavity ring-down spectrometers [Vogel et al. 2013] of two "sister sites" in the vicinity of Toronto, Canada is contrasted to recent observations of 13CO2 observations in Paris during significant pollution events. Using Miller-Tans plots [Miller and Tans, 2003] for our multi-season observations reveals significant changes of the source signatures of night time CO2 emissions which reflect the importance of natural gas burning in Megacities (up to 80% of fossil fuel sources) and show-case the potential of future isotope studies to determine source sectors. Especially the winter data this approach seems suitable to determine the source contribution of different fuel types (natural gas, liquid fuels and coal) which can inform the interpretation of other Greenhouse Gases and air pollution levels.

  12. PERSPECTIVE: Keeping a closer eye on fossil fuel CO2

    NASA Astrophysics Data System (ADS)

    Nelson, Peter F.

    2009-12-01

    all have a major influence on progress to an international agreement. It is important that the political challenges are not underestimated. Long-term observers of the negotiations necessary for global agreements (Inman 2009) are pessimistic about the chances for success at COP15, and argue that agreements between smaller groups of countries may be more effective. China and other developing countries clearly expect greater emission cuts by developed nations as a condition for a successful deal (Pan 2009). Conversely, the constraints on US climate policies are considerable, notably those imposed by fears that an international agreement that does not include equitable emission control measures for developing countries like China and India, will compromise the agreement and reduce its effectiveness (Skodvin and Andresen 2009). In this context the need for earlier, and more reliable, information on emissions is a high priority. Myhre and coworkers (Myhre et al 2009) provide an efficient method for calculating global carbon dioxide emissions from fossil fuel combustion by combining industry statistics with data from the Carbon Dioxide Information Analysis Center (CDIAC; http://cdiac.ornl.gov/). Recent analyses of carbon dioxide emission data show a worrying acceleration in emissions, beyond even the most extreme IPCC projections, but are based largely on the CDIAC which gives information about emissions released two to three years before real time (Canadell et al 2007, Raupach et al 2007). The approach used by Myhre et al (2009) uses BP annual statistics of fossil fuel consumption and has a much shorter lag, of the order of six months. Of significant concern is that their analysis of the data also reveals that the recent strong increase in fossil fuel CO2 is largely driven by an increase in emissions from coal, most significantly in China. By contrast, emissions from oil and gas continue to follow longer-term historical trends. Earlier and accurate data on CO2 emissions is

  13. Reducing risk in basin scale CO2 sequestration: a framework for integrated monitoring design.

    PubMed

    Seto, C J; McRae, G J

    2011-02-01

    Injection of CO(2) into geological structures is a key technology for sequestering CO(2) emissions captured from the combustion of fossil fuels. Current projects inject volumes on the order of megatonnes per year. However, injection volumes must be increased by several orders of magnitude for material reductions in ambient concentrations. A number of questions surrounding safety and security of injection have been raised about the large scale deployment of geological CO(2) sequestration. They are site specific and require an effective monitoring strategy to mitigate risks of concern to stakeholders. This paper presents a model-based framework for monitoring design that can provide a quantitative understanding of the trade-offs between operational decisions of cost, footprint size, and uncertainty in monitoring strategies. Potential risks and challenges of monitoring large scale CO(2) injection are discussed, and research areas needed to address uncertainties are identified. Lack of clear guidance surrounding monitoring has contributed to hampering the development of policies to promote the deployment of large scale sequestration projects. Modeling provides an understanding of site specific processes and allows insights into the complexity of these systems, facilitating the calibration of an appropriate plan to manage risk. An integrated policy for risk-based monitoring design, prior to large scale deployment of sequestration will ensure safe and secure storage through an understanding of the real risks associated with large scale injection.

  14. Linking emissions of fossil fuel CO2 and other anthropogenic trace gases using atmospheric 14CO2

    NASA Astrophysics Data System (ADS)

    Miller, John B.; Lehman, Scott J.; Montzka, Stephen A.; Sweeney, Colm; Miller, Benjamin R.; Karion, Anna; Wolak, Chad; Dlugokencky, Ed J.; Southon, John; Turnbull, Jocelyn C.; Tans, Pieter P.

    2012-04-01

    Atmospheric CO2 gradients are usually dominated by the signal from net terrestrial biological fluxes, despite the fact that fossil fuel combustion fluxes are larger in the annual mean. Here, we use a six year long series of 14CO2 and CO2 measurements obtained from vertical profiles at two northeast U.S. aircraft sampling sites to partition lower troposphere CO2 enhancements (and depletions) into terrestrial biological and fossil fuel components (Cbio and Cff). Mean Cff is 1.5 ppm, and 2.4 ppm when we consider only planetary boundary layer samples. However, we find that the contribution of Cbio to CO2 enhancements is large throughout the year, and averages 60% in winter. Paired observations of Cff and the lower troposphere enhancements (Δgas) of 22 other anthropogenic gases (CH4, CO, halo- and hydrocarbons and others) measured in the same samples are used to determine apparent emission ratios for each gas. We then scale these ratios by the well known U.S. fossil fuel CO2 emissions to provide observationally based estimates of national emissions for each gas and compare these to "bottom up" estimates from inventories. Correlations of Δgas with Cff for almost all gases are statistically significant with median r2for winter, summer and the entire year of 0.59, 0.45, and 0.42, respectively. Many gases exhibit statistically significant winter:summer differences in ratios that indicate seasonality of emissions or chemical destruction. The variability of ratios in a given season is not readily attributable to meteorological or geographic variables and instead most likely reflects real, short-term spatiotemporal variability of emissions.

  15. Self-Potential Monitoring for Geologic CO2 Sequestration

    NASA Astrophysics Data System (ADS)

    Nishi, Y.; Tosha, T.; Ishido, T.

    2009-12-01

    To appraise the utility of geophysical techniques for monitoring CO2 injected into aquifers, we carried out numerical simulations of an aquifer system underlying a portion of Tokyo Bay and calculated the temporal changes in geophysical observables caused by changing underground conditions as computed by the reservoir simulation. We used the STAR general-purpose reservoir simulator with the CO2SQS equation-of-state package (Pritchett, 2005) which treats three fluid phases (liquid- and gaseous-phase CO2 and an aqueous liquid phase) to calculate the evolution of reservoir conditions, and then used various “geophysical postprocessors” to calculate the resulting temporal changes in the earth-surface distributions of microgravity, apparent resistivity (from either DC or MT surveys), seismic observables and electrical self-potential (SP). The applicability of any particular method is likely to be highly site-specific, but these calculations indicate that none of these techniques should be ruled out altogether. In case of SP, CO2 injection does not create large electric signals through electrokinetic coupling within the saline aquifer owing to small coupling coefficients under the high salinity conditions. However, if a substantial pressure disturbance is induced to shallower levels where the interface between shallower fresh- and deeper saline-waters (which works as the boundary between regions of differing streaming potential coefficient) is present, obvious SP changes can appear on the ground surface. Continuous and/or repeat SP measurements are thought to be a promising geophysical technique to monitor pressure changes in shallower levels than the saline aquifer where CO2 is injected. In addition to SP measurements in a relatively wide area like covering the horizontal extent of CO2 plume, SP monitoring in a local area around a deep well is thought to be worthwhile from a different angle. SP anomalies of negative polarity are frequently observed near deep wells

  16. CO2 leakage monitoring and analysis to understand the variation of CO2 concentration in vadose zone by natural effects

    NASA Astrophysics Data System (ADS)

    Joun, Won-Tak; Ha, Seung-Wook; Kim, Hyun Jung; Ju, YeoJin; Lee, Sung-Sun; Lee, Kang-Kun

    2017-04-01

    Controlled ex-situ experiments and continuous CO2 monitoring in the field are significant implications for detecting and monitoring potential leakage from CO2 sequestration reservoir. However, it is difficult to understand the observed parameters because the natural disturbance will fluctuate the signal of detections in given local system. To identify the original source leaking from sequestration reservoir and to distinguish the camouflaged signal of CO2 concentration, the artificial leakage test was conducted in shallow groundwater environment and long-term monitoring have been performed. The monitoring system included several parameters such as pH, temperature, groundwater level, CO2 gas concentration, wind speed and direction, atmospheric pressure, borehole pressure, and rainfall event etc. Especially in this study, focused on understanding a relationship among the CO2 concentration, wind speed, rainfall and pressure difference. The results represent that changes of CO2 concentration in vadose zone could be influenced by physical parameters and this reason is helpful in identifying the camouflaged signal of CO2 concentrations. The 1-D column laboratory experiment also was conducted to understand the sparking-peak as shown in observed data plot. The results showed a similar peak plot and could consider two assumptions why the sparking-peak was shown. First, the trapped CO2 gas was escaped when the water table was changed. Second, the pressure equivalence between CO2 gas and water was broken when the water table was changed. These field data analysis and laboratory experiment need to advance due to comprehensively quantify local long-term dynamics of the artificial CO2 leaking aquifer. Acknowledgement Financial support was provided by the "R&D Project on Environmental Management of Geologic CO2 Storage" from the KEITI (Project Number: 2014001810003)

  17. Energy and climate impacts of producing synthetic hydrocarbon fuels from CO(2).

    PubMed

    van der Giesen, Coen; Kleijn, René; Kramer, Gert Jan

    2014-06-17

    Within the context of carbon dioxide (CO2) utilization there is an increasing interest in using CO2 as a resource to produce sustainable liquid hydrocarbon fuels. When these fuels are produced by solely using solar energy they are labeled as solar fuels. In the recent discourse on solar fuels intuitive arguments are used to support the prospects of these fuels. This paper takes a quantitative approach to investigate some of the claims made in this discussion. We analyze the life cycle performance of various classes of solar fuel processes using different primary energy and CO2 sources. We compare their efficacy with respect to carbon mitigation with ubiquitous fossil-based fuels and conclude that producing liquid hydrocarbon fuels starting from CO2 by using existing technologies requires much more energy than existing fuels. An improvement in life cycle CO2 emissions is only found when solar energy and atmospheric CO2 are used. Producing fuels from CO2 is a very long-term niche at best, not the panacea suggested in the recent public discourse.

  18. Geophysical Monitoring for the Frio Pilot CO2 Injection Test

    NASA Astrophysics Data System (ADS)

    Myer, L.; Hovorka, S.; Daley, T.; Wilt, M.

    2004-12-01

    The Frio Pilot test involves injection of approximately 3000 tons of CO2 into the brine-saturated Frio formation at a depth of approximately 1500 m at a test site located northeast of Houston. Interpretation of 3-D seismic coupled with petrophysical analyses and other geologic data showed that the test site is located in a small fault block off the flank of a salt dome. The CO2 is injected into a 10 m thick sand layer in an interval of alternating sand and shale layers overlain by the 75 m thick Anahuac shale. Well logs in the new well provide data to confirm test site stratigraphy as well as data needed for interpretation of geophysical monitoring measurements. Geophysical monitoring, which is augmented by hydrologic pressure measurements and geochemical sampling, involves time-lapse measurements, incorporating both surface and borehole techniques. A vertical seismic profiling (VSP) survey was designed for both monitoring and imaging the structure in the injection volume, and involved 8 explosive shot points at 100 - 1500 m offsets. An 80 level receiver string with 240 3-component sensors was used. Crosswell surveys involved P- and S-wave seismic and electromagnetic (EM) measurements (between steel-cased wells) at 1.5 m spacing over a 75 m interval. EM measurements were at 50 and 80Hz, and an orbital-vibrator seismic source provided seismic data in the 150Hz frequency range. Joint interpretation of crosswell seismic and EM with appropriate rock physics models can potentially provide quantitative information on CO2 saturation between boreholes.

  19. Spectral-element simulations of carbon dioxide (CO2) sequestration time-lapse monitoring

    NASA Astrophysics Data System (ADS)

    Morency, C.; Luo, Y.; Tromp, J.

    2009-12-01

    Geologic sequestration of CO2, a green house gas, represents an effort to reduce the large amount of CO2 generated as a by-product of fossil fuels combustion and emitted into the atmosphere. This process of sequestration involves CO2 storage deep underground. There are three main storage options: injection into hydrocarbon reservoirs, injection into methane-bearing coal beds, or injection into deep saline aquifers, that is, highly permeable porous media. The key issues involve accurate monitoring of the CO2, from the injection stage to the prediction & verification of CO2 movement over time for environmental considerations. A natural non-intrusive monitoring technique is referred to as ``4D seismics'', which involves 3D time-lapse seismic surveys. The success of monitoring the CO2 movement is subject to a proper description of the physics of the problem. We propose to realize time-lapse migrations comparing acoustic, elastic, and poroelastic simulations of 4D seismic imaging to characterize the storage zone. This approach highlights the influence of using different physical theories on interpreting seismic data, and, more importantly, on extracting the CO2 signature from the seismic wave field. Our simulations are performed using a spectral-element method, which allows for highly accurate results. Biot's equations are implemented to account for poroelastic effects. Attenuation associated with the anelasticity of the rock frame and frequency-dependent viscous resistance of the pore fluid are accommodated based upon a memory variable approach. The sensitivity of observables to the model parameters is quantified based upon finite-frequency sensitivity kernels calculated using an adjoint method.

  20. Field Tests of Real-time In-situ Dissolved CO2 Monitoring for CO2 Leakage Detection in Groundwater

    NASA Astrophysics Data System (ADS)

    Yang, C.; Zou, Y.; Delgado, J.; Guzman, N.; Pinedo, J.

    2016-12-01

    Groundwater monitoring for detecting CO2 leakage relies on groundwater sampling from water wells drilled into aquifers. Usually groundwater samples are required be collected periodically in field and analyzed in the laboratory. Obviously groundwater sampling is labor and cost-intensive for long-term monitoring of large areas. Potential damage and contamination of water samples during the sampling process can degrade accuracy, and intermittent monitoring may miss changes in the geochemical parameters of groundwater, and therefore signs of CO2 leakage. Real-time in-situ monitoring of geochemical parameters with chemical sensors may play an important role for CO2 leakage detection in groundwater at a geological carbon sequestration site. This study presents field demonstration of a real-time in situ monitoring system capable of covering large areas for detection of low levels of dissolved CO2 in groundwater and reliably differentiating natural variations of dissolved CO2 concentration from small changes resulting from leakage. The sand-alone system includes fully distributed fiber optic sensors for carbon dioxide detection with a unique sensor technology developed by Intelligent Optical Systems. The systems were deployed to the two research sites: the Brackenridge Field Laboratory where the aquifer is shallow at depths of 10-20 ft below surface and the Devine site where the aquifer is much deeper at depths of 140 to 150 ft. Groundwater samples were periodically collected from the water wells which were installed with the chemical sensors and further compared to the measurements of the chemical sensors. Our study shows that geochemical monitoring of dissolved CO2 with fiber optic sensors could provide reliable CO2 leakage signal detection in groundwater as long as CO2 leakage signals are stronger than background noises at the monitoring locations.

  1. Quantification of fossil fuel CO2 at the building/street level for large US cities

    NASA Astrophysics Data System (ADS)

    Gurney, K. R.; Razlivanov, I. N.; Song, Y.

    2012-12-01

    Quantification of fossil fuel CO2 emissions from the bottom-up perspective is a critical element in emerging plans on a global, integrated, carbon monitoring system (CMS). A space/time explicit emissions data product can act as both a verification and planning system. It can verify atmospheric CO2 measurements (in situ and remote) and offer detailed mitigation information to management authorities in order to optimize the mix of mitigation efforts. Here, we present the Hestia Project, an effort aimed at building a high resolution (eg. building and road link-specific, hourly) fossil fuel CO2 emissions data product for the urban domain as a pilot effort to a CMS. A complete data product has been built for the city of Indianapolis and preliminary quantification has been completed for Los Angeles and Phoenix (see figure). The effort in Indianapolis is now part of a larger effort aimed at a convergent top-down/bottom-up assessment of greenhouse gas emissions, called INFLUX. Our urban-level quantification relies on a mixture of data and modeling structures. We start with the sector-specific Vulcan Project estimate at the mix of geocoded and county-wide levels. The Hestia aim is to distribute the Vulcan result in space and time. Two components take the majority of effort: buildings and onroad emissions. In collaboration with our INFLUX colleagues, we are transporting these high resolution emissions through an atmospheric transport model for a forward comparison of the Hestia data product with atmospheric measurements, collected on aircraft and cell towers. In preparation for a formal urban-scale inversion, these forward comparisons offer insights into both improving our emissions data product and measurement strategies. A key benefit of the approach taken in this study is the tracking and archiving of fuel and process-level detail (eg. combustion process, other pollutants), allowing for a more thorough understanding and analysis of energy throughputs in the urban

  2. Soil CO2 Flux Monitoring for Geologic Carbon Storage: Assessing the Background CO2 Levels Prior to Artificial CO2 Release Experiment in Eumsung, Korea

    NASA Astrophysics Data System (ADS)

    Yun, H. M.; Kim, S.; Park, M. J.; Han, S. H.; Son, Y.

    2015-12-01

    With potential risks of CO2 leakage and subsequent impacts on surrounding abiotic and biotic environments, development of adequate monitoring strategies is essential for successful geologic carbon storage (GCS). To accomplish such goal, a controlled artificial CO2 release experiment site has been established in Eumsung, Korea. Prior to the scheduled release in fall 2015 at the depth of 2.5 m, grid measurements of soil CO2 fluxes at the surface and shallow subsoil CO2 concentrations at various depths were conducted periodically in order to assess the background soil respiration fluxes. Following the installation of automated soil flux chambers, the mean flux was found to be 2.1 μmol m-2 s-1 over the period of June to August 2015. However, as expected, spatial and temporal variations of the CO2 flux among the chambers were observed, ranging from about 0.5 to 4.0 μmol m-2 s-1. In addition, it was found that rainfalls, including few incidents of heavy monsoonal rain, have hindered the collection of reliable data. Spatiotemporal variability of soil CO2 flux is due to its strong dependence on surrounding soil conditions (i.e. temperature and soil moisture content) and meteorological conditions. Hence by integrating the results obtained by portable accumulation flux chamber method and subsoil CO2 concentration measurements along with environmental data, we expect to produce a more reliable background value. In addition to expanding the sampling area, subsoil CO2 concentration measurements at various depths is also expected to provide valuable observations on the evolution and vertical movement of CO2 through the soil profile to the surface. Carefully assessed background CO2 flux level, from monitoring over a sufficiently long-term site characterization period and when its spatiotemporal variability is well understood, will be the key to successful leakage detection in GCS facilities. ※ This subject is supported by Korea Ministry of Environment (MOE) as "K

  3. Hyperspectral Geobotanical Remote Sensing for CO2 Storage Monitoring

    SciTech Connect

    Pickles, W; Cover, W

    2004-05-14

    commercial hyperspectral image processing software. We have also begun to use the high resolution (0.6 meter) commercial satellite QuickBird in our technology development. This hyperspectral imaging project for CO2 leakage monitoring has focused on using the extensive hyperspectral imagery set that we acquired of the Rangely CO enhanced oil recovery field in August 2002. We have accomplished extensive analysis of this imagery. We have created highly detailed maps of soil types, plant coverages, plant health, local ecologies or habitats, water conditions, and manmade objects throughout the entire Rangely Oil field and surrounding areas. The results were verified during a field trip to Rangely CO in August 2003. These maps establish an environmental and ecological baseline against which any future CO2 leakage effects on the plants, plant habitats, soils and water conditions can be detected and verified. We have also seen signatures that may be subtle hidden faults. If confirmed these faults might provide pathways for upward CO2 migration if that occurred at any time during the future. We have found a result that was unexpected, new to us, and potentially very important to the task of monitoring for CO2 that has leaked to within the plant root depths near the surface. The discovery is that one of our analysis techniques has picked out finely detailed mapping of local ecologies. Some of which are found to extend across the entire Rangely oil field and into the surrounding areas. These ecologies appear to be made up of a fairly narrow range of percentage admixtures of two or three very specific plant types and soil types. It is likely that any large amounts of CO2 reaching the root depth near the surface would begin to modify the shapes of the habitats. These habitat changes will be easy to detect by repeat imaging of the area. The habitat modification signature is probably detectable earlier following the start of CO2 build up in the soil, than looking for individual plant

  4. 21 CFR 868.2480 - Cutaneous carbon dioxide (PcCO2) monitor.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cutaneous carbon dioxide (PcCO2) monitor. 868.2480... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2480 Cutaneous carbon dioxide (PcCO2) monitor. (a) Identification. A cutaneous carbon dioxide (PcCO2) monitor is a noninvasive heated...

  5. 21 CFR 868.2480 - Cutaneous carbon dioxide (PcCO2) monitor.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cutaneous carbon dioxide (PcCO2) monitor. 868.2480... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2480 Cutaneous carbon dioxide (PcCO2) monitor. (a) Identification. A cutaneous carbon dioxide (PcCO2) monitor is a noninvasive heated...

  6. 21 CFR 868.2480 - Cutaneous carbon dioxide (PcCO2) monitor.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cutaneous carbon dioxide (PcCO2) monitor. 868.2480... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2480 Cutaneous carbon dioxide (PcCO2) monitor. (a) Identification. A cutaneous carbon dioxide (PcCO2) monitor is a noninvasive heated...

  7. Wine ethanol 14C as a tracer for fossil fuel CO2 emissions in Europe: Measurements and model comparison

    NASA Astrophysics Data System (ADS)

    Palstra, Sanne W. L.; Karstens, Ute; Streurman, Harm-Jan; Meijer, Harro A. J.

    2008-11-01

    14C (radiocarbon) in atmospheric CO2 is the most direct tracer for the presence of fossil-fuel-derived CO2 (CO2-ff). We demonstrate the 14C measurement of wine ethanol as a way to determine the relative regional atmospheric CO2-ff concentration compared to a background site ("regional CO2-ff excess") for specific harvest years. The carbon in wine ethanol is directly back traceable to the atmospheric CO2 that the plants assimilate. An important advantage of using wine is that the atmosphere can be monitored annually back in time. We have analyzed a total of 165 wines, mainly from harvest years 1990-1993 and 2003-2004, among which is a semicontinuous series (1973-2004) of wines from one vineyard in southwest Germany. The results show clear spatial and temporal variations in the regional CO2-ff excess values. We have compared our measured regional CO2-ff excess values of 2003 and 2004 with those simulated by the REgional MOdel (REMO). The model results show a bias of almost +3 parts per million (ppm) CO2-ff compared with those of the observations. The modeled differences between 2003 and 2004, however, which can be used as a measure for the variability in atmospheric mixing and transport processes, show good agreement with those of the observations all over Europe. Correcting for interannual variations using modeled data produces a regional CO2-ff excess signal that is potentially useful for the verification of trends in regional fossil fuel consumption. In this fashion, analyzing 14C from wine ethanol offers the possibility to observe fossil fuel emissions back in time on many places in Europe and elsewhere.

  8. Atmospheric Modeling and Verification of Point Source Fossil Fuel CO2 Emissions

    NASA Astrophysics Data System (ADS)

    Keller, E. D.; Turnbull, J. C.; Baisden, W. T.; Brailsford, G. W.; Bromley, T.; Norris, M. W.; Zondervan, A.

    2014-12-01

    Emissions from large point sources (electricity generation and large-scale industry) of fossil fuel CO2 (CO2ff) emissions are currently determined from self-reported "bottom-up" inventory data, with an uncertainty of about 20% for individual power plants. As the world moves towards a regulatory environment, there is a need for independent, objective measurements of these emissions both to improve the accuracy of and to verify the reported amounts. "Top-down" atmospheric methods have the potential to independently constrain point source emissions, combining observations with atmospheric transport modeling to derive emission estimates. We use the Kapuni Gas Treatment Plant to examine methodologies and model sensitivities for atmospheric monitoring of point source fossil fuel CO2 (CO2ff) emissions. The Kapuni plant, located in rural New Zealand, removes and vents CO2 from locally extracted natural gas at a rate of ~0.1 Tg carbon per year. We measured the CO2ff content in three different types of observations: air samples collected in flasks over a period of a few minutes, sodium hydroxide solution exposed the atmosphere, and grass samples from the surrounding farmland, the latter two representing ~1 week integrated averages. We use the WindTrax Lagrangian plume dispersion model to compare these atmospheric observations with "expected" values given the emissions reported by the Kapuni plant. The model has difficulty accurately capturing the short-term variability in the flask samples but does well in representing the longer-term averages from grass samples, suggesting that passive integrated-sampling methods have the potential to monitor long-term emissions. Our results indicate that using this method, point source emissions can be verified to within about 30%. Further improvements in atmospheric transport modelling are needed to reduce uncertainties. In view of this, we discuss model strengths and weaknesses and explore model sensitivity to meteorological conditions

  9. Long-term results from an urban CO2 monitoring network

    NASA Astrophysics Data System (ADS)

    Ehleringer, J.; Pataki, D. E.; Lai, C.; Schauer, A.

    2009-12-01

    High-precision atmospheric CO2 has been monitored in several locations through the Salt Lake Valley metropolitan region of northern Utah over the past nine years. Many parts of this semi-arid grassland have transitioned into dense urban forests, supported totally by extensive homeowner irrigation practices. Diurnal changes in fossil-fuel energy uses and photosynthesis-respiration processes have resulted in significant spatial and temporal variations in atmospheric CO2. Here we present an analysis of the long-term patterns and trends in midday and nighttime CO2 values for four sites: a midvalley residential neighborhood, a midvalley non-residential neighborhood, an undeveloped valley-edge area transitioning from agriculture, and a developed valley-edge neighborhood with mixed residential and commercial activities; the neighborhoods span an elevation gradient within the valley of ~100 m. Patterns in CO2 concentrations among neighborhoods were examined relative to each other and relative to the NOAA background station, a desert site in Wendover, Utah. Four specific analyses are considered. First, we present a statistical analysis of weekday versus weekend CO2 patterns in the winter, spring, summer, and fall seasons. Second, we present a statistical analysis of the influences of high-pressure systems on the elevation of atmospheric CO2 above background levels in the winter versus summer seasons. Third, we present an analysis of the nighttime CO2 values through the year, relating these patterns to observed changes in the carbon isotope ratios of atmospheric CO2. Lastly, we examine the rate of increase in midday urban CO2 over time relative to regional and global CO2 averages to determine if the amplification of urban energy use is statistically detectable from atmospheric trace gas measurements over the past decade. These results show two important patterns. First, there is a strong weekday-weekend effect of vehicle emissions in contrast to the temperature

  10. A Pilot Study to Evaluate California's Fossil Fuel CO2 Emissions Using Atmospheric Observations

    NASA Astrophysics Data System (ADS)

    Graven, H. D.; Fischer, M. L.; Lueker, T.; Guilderson, T.; Brophy, K. J.; Keeling, R. F.; Arnold, T.; Bambha, R.; Callahan, W.; Campbell, J. E.; Cui, X.; Frankenberg, C.; Hsu, Y.; Iraci, L. T.; Jeong, S.; Kim, J.; LaFranchi, B. W.; Lehman, S.; Manning, A.; Michelsen, H. A.; Miller, J. B.; Newman, S.; Paplawsky, B.; Parazoo, N.; Sloop, C.; Walker, S.; Whelan, M.; Wunch, D.

    2016-12-01

    Atmospheric CO2 concentration is influenced by human activities and by natural exchanges. Studies of CO2 fluxes using atmospheric CO2 measurements typically focus on natural exchanges and assume that CO2 emissions by fossil fuel combustion and cement production are well-known from inventory estimates. However, atmospheric observation-based or "top-down" studies could potentially provide independent methods for evaluating fossil fuel CO2 emissions, in support of policies to reduce greenhouse gas emissions and mitigate climate change. Observation-based estimates of fossil fuel-derived CO2 may also improve estimates of biospheric CO2 exchange, which could help to characterize carbon storage and climate change mitigation by terrestrial ecosystems. We have been developing a top-down framework for estimating fossil fuel CO2 emissions in California that uses atmospheric observations and modeling. California is implementing the "Global Warming Solutions Act of 2006" to reduce total greenhouse gas emissions to 1990 levels by 2020, and it has a diverse array of ecosystems that may serve as CO2 sources or sinks. We performed three month-long field campaigns in different seasons in 2014-15 to collect flask samples from a state-wide network of 10 towers. Using measurements of radiocarbon in CO2, we estimate the fossil fuel-derived CO2 present in the flask samples, relative to marine background air observed at coastal sites. Radiocarbon (14C) is not present in fossil fuel-derived CO2 because of radioactive decay over millions of years, so fossil fuel emissions cause a measurable decrease in the 14C/C ratio in atmospheric CO2. We compare the observations of fossil fuel-derived CO2 to simulations based on atmospheric modeling and published fossil fuel flux estimates, and adjust the fossil fuel flux estimates in a statistical inversion that takes account of several uncertainties. We will present the results of the top-down technique to estimate fossil fuel emissions for our field

  11. Lessons from Natural CO2 Leakage Analogue Site Studies and their Application to Secure CO2 Storage and Monitoring

    NASA Astrophysics Data System (ADS)

    Han, W.; McPherson, B. J.; Kim, K.; Chae, G.; Yum, B.

    2011-12-01

    related chemical reactions in the observation wells and tested with numerical simulation tools, which predicted thermal processes caused by solid NaCl precipitation, buoyancy-driven supercritical CO2 migration, and potential non-isothermal effects. Simulation results suggest that these processes - solid NaCl precipitation, buoyancy effects, Joule-Thomson cooling, water vaporization, and exothermic CO2 reactions - are strongly coupled and dynamic (transient). Overall, a fundamental understanding of potential thermal processes investigated through this research will be beneficial in the collection and analysis of temperature signals collectively measured from monitoring wells.

  12. VSP and Crosswell Seismic Monitoring of a CO2 Injection

    NASA Astrophysics Data System (ADS)

    Daley, T. M.; Myer, L. R.; Majer, E. L.

    2004-12-01

    The U.S. Department of Energy is conducting a small scale CO2 injection to test issues related to the geologic sequestration of CO2. The injection is taking place in southeast Texas in the Frio Formation. As part of this injection test, Lawrence Berkeley National Laboratory is conducting time-lapse seismic monitoring. Both VSP and crosswell surveys have been acquired as pre-injection baselines with a repeat post-injection survey planned. The VSP used an 80 level, 3-component geophone string with 7.5 m sensor spacing and explosive sources. Eight source shot points were acquired. The sensor string locations were interleaved resulting in 1.5 to 7.5 m spacings. The shotpoints were offset 100 to 1500 m from the sensor well on 4 azimuths. The location of the shotpoints was designed to monitor the estimated CO2 plume location and to provide structural information at the injection site. VSP data reveal good quality direct and reflected events. Upgoing and downgoing wavefields will be shown. Data repeatability is investigated because up to 10 shot holes were used at each shot point. Initial results show good repeatability for separate explosive shots. The crosswell survey also used the 80 level, 3-component geophone string along with an orbital vibrator borehole source. The orbital vibrator is capable of generating both P- and S-wave direct arrivals with frequency content of about 70 - 350 Hz. For the crosswell survey, both source and sensor spacing was 1.5 m. The crosswell survey was conducted using the planned injection well (for sensors) and a nearby monitoring well (for source) which is about 30 m offset. Crosswell source locations spanned about 75 m, centered on the injection interval. The crosswell sensors spanned about 300 m., also centered on the injection interval. The planned injection interval is the 6-7 m thick, upper C sand in the Frio formation which is at a depth of about 1500 m. Initial analysis of the crosswell data shows good quality P- and S-wave direct

  13. Reduction of CO2 to C1 products and fuel

    USGS Publications Warehouse

    Mill, T.; Ross, D.

    2002-01-01

    Photochemical semiconductor processes readily reduced CO2 to a broad range of C1 products. However the intrinsic and solar efficiencies for the processes were low. Improved quantum efficiencies could be realized utilizing quantum-sized particles, but at the expense of using less of the visible solar spectrum. Conversely, semiconductors with small bandgaps used more of the visible solar spectrum at the expense of quantum efficiency. Thermal reduction of CO2 with Fe(II) was thermodynamically favored for forming many kinds of organic compounds and occurred readily with olivine and other Fe(II) minerals above 200??C to form higher alkanes and alkenes. No added hydrogen was required.

  14. Assessing the potential long-term increase of oceanic fossil fuel CO2 uptake due to CO2-calcification feedback

    NASA Astrophysics Data System (ADS)

    Ridgwell, A.; Zondervan, I.; Hargreaves, J. C.; Bijma, J.; Lenton, T. M.

    2007-07-01

    Plankton manipulation experiments exhibit a wide range of sensitivities of biogenic calcification to simulated anthropogenic acidification of the ocean, with the "lab rat" of planktic calcifiers, Emiliania huxleyi apparently not representative of calcification generally. We assess the implications of this observational uncertainty by creating an ensemble of realizations of an Earth system model that encapsulates a comparable range of uncertainty in calcification response to ocean acidification. We predict that a substantial reduction in marine carbonate production is possible in the future, with enhanced ocean CO2 sequestration across the model ensemble driving a 4-13% reduction in the year 3000 atmospheric fossil fuel CO2 burden. Concurrent changes in ocean circulation and surface temperatures in the model contribute about one third to the increase in CO2 uptake. We find that uncertainty in the predicted strength of CO2-calcification feedback seems to be dominated by the assumption as to which species of calcifier contribute most to carbonate production in the open ocean.

  15. Quantification of uncertainty associated with United States high resolution fossil fuel CO2 emissions: updates, challenges and future plans

    NASA Astrophysics Data System (ADS)

    Gurney, K. R.; Chandrasekaran, V.; Mendoza, D. L.; Geethakumar, S.

    2010-12-01

    The Vulcan Project has estimated United States fossil fuel CO2 emissions at the hourly time scale and at spatial scales below the county level for the year 2002. Vulcan is built from a wide variety of observational data streams including regulated air pollutant emissions reporting, traffic monitoring, energy statistics, and US census data. In addition to these data sets, Vulcan relies on a series of modeling assumptions and constructs to interpolate in space, time and transform non-CO2 reporting into an estimate of CO2 combustion emissions. The recent version 2.0 of the Vulcan inventory has produced advances in a number of categories with particular emphasis on improved temporal structure. Onroad transportation emissions now avail of roughly 5000 automated traffic count monitors allowing for much improved diurnal and weekly time structure in our onroad transportation emissions. Though the inventory shows excellent agreement with independent national-level CO2 emissions estimates, uncertainty quantification has been a challenging task given the large number of data sources and numerous modeling assumptions. However, we have now accomplished a complete uncertainty estimate across all the Vulcan economic sectors and will present uncertainty estimates as a function of space, time, sector and fuel. We find that, like the underlying distribution of CO2 emissions themselves, the uncertainty is also strongly lognormal with high uncertainty associated with a relatively small number of locations. These locations typically are locations reliant upon coal combustion as the dominant CO2 source. We will also compare and contrast Vulcan fossil fuel CO2 emissions estimates against estimates built from DOE fuel-based surveys at the state level. We conclude that much of the difference between the Vulcan inventory and DOE statistics are not due to biased estimation but mechanistic differences in supply versus demand and combustion in space/time.

  16. 21 CFR 868.2480 - Cutaneous carbon dioxide (PcCO 2) monitor.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cutaneous carbon dioxide (PcCO 2) monitor. 868... dioxide (PcCO 2) monitor. (a) Identification. A cutaneous carbon dioxide (PcCO2) monitor is a noninvasive... relative changes in a hemodynamically stable patient's cutaneous carbon dioxide tension as an adjunct to...

  17. 21 CFR 868.2480 - Cutaneous carbon dioxide (PcCO 2) monitor.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cutaneous carbon dioxide (PcCO 2) monitor. 868... dioxide (PcCO 2) monitor. (a) Identification. A cutaneous carbon dioxide (PcCO2) monitor is a noninvasive... relative changes in a hemodynamically stable patient's cutaneous carbon dioxide tension as an adjunct to...

  18. 40 CFR 75.13 - Specific provisions for monitoring CO 2 emissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Specific provisions for monitoring CO... provisions for monitoring CO 2 emissions. (a) CO 2 continuous emission monitoring system. If the owner or...” shall apply rather than “SO2 mass emissions.” (b) Determination of CO 2 emissions using appendix G...

  19. 40 CFR 75.13 - Specific provisions for monitoring CO 2 emissions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Specific provisions for monitoring CO... provisions for monitoring CO 2 emissions. (a) CO 2 continuous emission monitoring system. If the owner or...” shall apply rather than “SO2 mass emissions.” (b) Determination of CO 2 emissions using appendix G...

  20. Model Selection for Monitoring CO2 Plume during Sequestration

    SciTech Connect

    2014-12-31

    The model selection method developed as part of this project mainly includes four steps: (1) assessing the connectivity/dynamic characteristics of a large prior ensemble of models, (2) model clustering using multidimensional scaling coupled with k-mean clustering, (3) model selection using the Bayes' rule in the reduced model space, (4) model expansion using iterative resampling of the posterior models. The fourth step expresses one of the advantages of the method: it provides a built-in means of quantifying the uncertainty in predictions made with the selected models. In our application to plume monitoring, by expanding the posterior space of models, the final ensemble of representations of geological model can be used to assess the uncertainty in predicting the future displacement of the CO2 plume. The software implementation of this approach is attached here.

  1. Quantification of fossil fuel CO2 emissions on the building/street scale for a large U.S. city.

    PubMed

    Gurney, Kevin R; Razlivanov, Igor; Song, Yang; Zhou, Yuyu; Benes, Bedrich; Abdul-Massih, Michel

    2012-11-06

    In order to advance the scientific understanding of carbon exchange with the land surface, build an effective carbon monitoring system, and contribute to quantitatively based U.S. climate change policy interests, fine spatial and temporal quantification of fossil fuel CO(2) emissions, the primary greenhouse gas, is essential. Called the "Hestia Project", this research effort is the first to use bottom-up methods to quantify all fossil fuel CO(2) emissions down to the scale of individual buildings, road segments, and industrial/electricity production facilities on an hourly basis for an entire urban landscape. Here, we describe the methods used to quantify the on-site fossil fuel CO(2) emissions across the city of Indianapolis, IN. This effort combines a series of data sets and simulation tools such as a building energy simulation model, traffic data, power production reporting, and local air pollution reporting. The system is general enough to be applied to any large U.S. city and holds tremendous potential as a key component of a carbon-monitoring system in addition to enabling efficient greenhouse gas mitigation and planning. We compare the natural gas component of our fossil fuel CO(2) emissions estimate to consumption data provided by the local gas utility. At the zip code level, we achieve a bias-adjusted Pearson r correlation value of 0.92 (p < 0.001).

  2. [Monitoring Atmospheric CO2 and delta(13)C (CO2) Background Levels at Shangdianzi Station in Beijing, China].

    PubMed

    Xia, Ling-ju; Zhou, Ling-xi; Liu, Li-xin; Zhang, Gen

    2016-04-15

    The study presented time series of atmospheric CO2 concentrations from flask sampling at SDZ regional station in Beijing during 2007 and 2013, together with delta(13)CO2) values during 2009 and 2013. The "representative data" of CO2 and delta(13)C (CO2) were selected from the complete data for further analysis. Annual CO2 concentrations increased from 385.6 x 10(-6) in 2007 to 398.1 x 10(-6) in 2013, with an average growth rate of 2.0 x 10(-6) a(-1), while the delta(13)C values decreased from -8.38% per hundred in 2009 to -8.52% per hundred in 2013, with a mean growth rate of -0.03% per hundred x a(-1). The absolute increase of CO2 from 2007 to 2008 reached the lowest level during 2007 and 2013, possibly due to relatively less carbon emissions during the 2008 Olympic Games period. The peak-to-peak amplitudes of atmospheric CO2 and delta(13)C seasonal variations were 23. 9 x 10 -6 and 1. 03%o, respectively. The isotopic signatures of CO2 sources/sinks were also discussed in this study. The delta8 value for heating season I (Jan. 01-Mar. 14) was -21.30% per hundred, while -25.39% per hundred for heating season 11 (Nov. 15-Dec.31) , and for vegetative season (Mar. 15-Nov. 14) the delta(bio) value was estimated to be -21.28% per hundred, likely suggesting the significant impact of fossil fuel and corn straw combustions during winter heating season and biological activities during vegetative season.

  3. Characterizing Uncertainties in Atmospheric Inversions of Fossil Fuel CO2 Emissions in California

    NASA Astrophysics Data System (ADS)

    Brophy, K. J.; Graven, H. D.; Manning, A.; Arnold, T.; Fischer, M. L.; Jeong, S.; Cui, X.; Parazoo, N.

    2016-12-01

    In 2006 California passed a law requiring greenhouse gas emissions be reduced to 1990 levels by 2020, equivalent to a 20% reduction over 2006-2020. Assessing compliance with greenhouse gas mitigation policies requires accurate determination of emissions, particularly for CO2 emitted by fossil fuel combustion (ffCO2). We found differences in inventory-based ffCO2 flux estimates for California total emissions of 11% (standard deviation relative to the mean), and even larger differences on some smaller sub-state levels. Top-down studies may be useful for validating ffCO2 flux estimates, but top-down studies of CO2 typically focus on biospheric CO2 fluxes and they are not yet well-developed for ffCO2. Implementing top-down studies of ffCO2 requires observations of a fossil fuel combustion tracer such as 14C to distinguish ffCO2 from biospheric CO2. However, even if a large number of 14C observations are available, multiple other sources of uncertainty will contribute to the uncertainty in posterior ffCO2 flux estimates. With a Bayesian inverse modelling approach, we use simulated atmospheric observations of ffCO2 at a network of 11 tower sites across California in an observing system simulation experiment to investigate uncertainties. We use four different prior ffCO2 flux estimates, two different atmospheric transport models, different types of spatial aggregation, and different assumptions for observational and model transport uncertainties to investigate contributions to posterior ffCO2 emission uncertainties. We show how various sources of uncertainty compare and which uncertainties are likely to limit top-down estimation of ffCO2 fluxes in California.

  4. Can the envisaged reductions of fossil fuel CO2 emissions be detected by atmospheric observations?

    PubMed

    Levin, Ingeborg; Rödenbeck, Christian

    2008-03-01

    The lower troposphere is an excellent receptacle, which integrates anthropogenic greenhouse gases emissions over large areas. Therefore, atmospheric concentration observations over populated regions would provide the ultimate proof if sustained emissions changes have occurred. The most important anthropogenic greenhouse gas, carbon dioxide (CO(2)), also shows large natural concentration variations, which need to be disentangled from anthropogenic signals to assess changes in associated emissions. This is in principle possible for the fossil fuel CO(2) component (FFCO(2)) by high-precision radiocarbon ((14)C) analyses because FFCO(2) is free of radiocarbon. Long-term observations of (14)CO(2) conducted at two sites in south-western Germany do not yet reveal any significant trends in the regional fossil fuel CO(2) component. We rather observe strong inter-annual variations, which are largely imprinted by changes of atmospheric transport as supported by dedicated transport model simulations of fossil fuel CO(2). In this paper, we show that, depending on the remoteness of the site, changes of about 7-26% in fossil fuel emissions in respective catchment areas could be detected with confidence by high-precision atmospheric (14)CO(2) measurements when comparing 5-year averages if these inter-annual variations were taken into account. This perspective constitutes the urgently needed tool for validation of fossil fuel CO(2) emissions changes in the framework of the Kyoto protocol and successive climate initiatives.

  5. Will elevated CO2 alter fuel characteristics and flammability of eucalypt woodlands?

    NASA Astrophysics Data System (ADS)

    Collins, Luke; Resco, Victor; Boer, Matthias; Bradstock, Ross; Sawyer, Robert

    2016-04-01

    Rising atmospheric CO2 may enhance forest productivity via CO2 fertilisation and increased soil moisture associated with water savings, potentially resulting in increased woody plant abundance i.e. woody thickening. Changes to vegetation structure via woody thickening, as well as changes to vegetation properties (e.g. leaf characteristics and moisture content), may have important implications for ecosystem flammability and fire regimes. Understanding how elevated CO2 alters flammability and fire regimes will have implications for ecosystem dynamics, particularly carbon sequestration and emissions. We present data from Free Air CO2 Enrichment (EucFACE) and whole tree growth chamber (WTC) experiments to assess the effect of elevated CO2 on fuel properties and flammability of eucalypt woodlands. Experiments involved ambient (˜400 ppm) and elevated CO2treatments, with elevated treatments being +150 ppm and +240 ppm at EucFACE and the WTCs respectively. We examined the response of vegetation parameters known to influence ecosystem flammability, namely (i) understorey vegetation characteristics (ii) understorey fuel moisture and (iii) leaf flammability. Understorey growth experiments at EucFACE using seedlings of two common woody species (Hakea sericia, Eucalyptus tereticornis) indicate that elevated CO2 did not influence stem and leaf biomass, height or crown dimensions of seedlings after 12 months exposure to experimental treatments. Temporal changes to understorey live fuel moisture were assessed at EucFACE over an 18 month period using time lapse cameras. Understorey vegetation greenness was measured daily from digital photos using the green chromatic coordinate (GCC), an index that is highly correlated with live fuel moisture (R2 = 0.90). GCC and rates of greening and browning were not affected by elevated CO2, though they were highly responsive to soil moisture availability and temperature. This suggests that there is limited potential for elevated CO2 to alter

  6. First results of geodetic deformation monitoring after commencement of CO2 injection at the Aquistore underground CO2 storage site

    NASA Astrophysics Data System (ADS)

    Craymer, M.; White, D.; Piraszewski, M.; Zhao, Y.; Henton, J.; Silliker, J.; Samsonov, S.

    2015-12-01

    Aquistore is a demonstration project for the underground storage of CO2 at a depth of ~3350 m near Estevan, Saskatchewan, Canada. An objective of the project is to design, adapt, and test non-seismic monitoring methods that have not been systematically utilized to date for monitoring CO2 storage projects, and to integrate the data from these various monitoring tools to obtain quantitative estimates of the change in subsurface fluid distributions, pressure changes and associated surface deformation. Monitoring methods being applied include satellite-, surface- and wellbore-based monitoring systems and comprise natural- and controlled-source electromagnetic methods, gravity monitoring, continuous GPS, synthetic aperture radar interferometry (InSAR), tiltmeter array analysis, and chemical tracer studies. Here we focus on the GPS, InSAR and gravity monitoring. Five monitoring sites were installed in 2012 and another six in 2013, each including GPS and InSAR corner reflector monuments (some collocated on the same monument). The continuous GPS data from these stations have been processed on a daily basis in both baseline processing mode using the Bernese GPS Software and precise point positioning mode using CSRS-PPP. Gravity measurements at each site have also been performed in fall 2013, spring 2014 and fall 2015, and at two sites in fall 2014. InSAR measurements of deformation have been obtained for a 5 m footprint at each site as well as at the corner reflector point sources. Here we present the first results of this geodetic deformation monitoring after commencement of CO2 injection on April 14, 2015. The time series of these sites are examined, compared and analyzed with respect to monument stability, seasonal signals, longer term trends, and any changes in motion and mass since CO2 injection.

  7. Quantification of space/time explicit fossil fuel CO2 emissions in urban domes

    NASA Astrophysics Data System (ADS)

    Gurney, K. R.; Razlivanov, I.; Zhou, Y.; Song, Y.; Turnbull, J. C.; Sweeney, C.; Karion, A.; Davis, K. J.; Miles, N. L.; Richardson, S.; Lauvaux, T.; Shepson, P. B.; Cambaliza, M. L.; Lehman, S. J.; Tans, P. P.

    2011-12-01

    Quantification of fossil fuel CO2 emissions from the bottom-up perspective is a critical element in emerging plans on a carbon monitoring system (CMS). A space/time explicit emissions data product can act as both a verification and planning system. It can verify atmospheric CO2 measurements (in situ and remote) and offer detailed mitigation information to local management authorities in order to optimize the mix of mitigation efforts. Here, we present the Hestia Project, an effort aimed at building a high resolution (eg. building and road link-specific, hourly) fossil fuel CO2 emissions data products for the urban domain. A complete data product has been built for the city of Indianapolis and work is ongoing for the city of Los Angeles. The effort in Indianapolis is now part of a larger effort aimed at a convergent top-down/bottom-up assessment of greenhouse gas emissions, called INFLUX. Our urban-level quantification relies on a mixture of data and modeling structures. We start with the sector-specific Vulcan Project estimate at the mix of geocoded and county-wide levels. The Hestia aim is to distribute the Vulcan result in space and time. Two components take the majority of effort: buildings and onroad emissions. For the buildings, we utilize an energy building model which we constrain through lidar data, county assessor parcel data and GIS layers. For onroad emissions, we use a combination of traffic data and GIS road layers maintaining vehicle class information. Finally, all pointwise data in the Vulcan Project are transferred to our urban landscape and additional time distribution is performed. In collaboration with our INFLUX colleagues, we are transporting these high resolution emissions through an atmospheric transport model for a forward comparison of the Hestia data product with atmospheric measurements, collected on aircraft and cell towers. In preparation for a formal urban-scale inversion, these forward comparisons offer insights into both improving

  8. Radiocarbon-depleted CO2 evidence for fuel biodegradation at the Naval Air Station North Island (USA) fuel farm site.

    PubMed

    Boyd, Thomas J; Pound, Michael J; Lohr, Daniel; Coffin, Richard B

    2013-05-01

    Dissolved CO(2) radiocarbon and stable carbon isotope ratios were measured in groundwater from a fuel contaminated site at the North Island Naval Air Station in San Diego, CA (USA). A background groundwater sampling well and 16 wells in the underground fuel contamination zone were evaluated. For each sample, a two end-member isotopic mixing model was used to determine the fraction of CO(2) derived from fossil fuel. The CO(2) fraction from fossil sources ranged from 8 to 93% at the fuel contaminated site, while stable carbon isotope values ranged from -14 to +5‰VPDB. Wells associated with highest historical and contemporary fuel contamination showed the highest fraction of CO(2) derived from petroleum (fossil) sources. Stable carbon isotope ratios indicated sub-regions on-site with recycled CO(2) (δ(13)CO(2) as high as +5‰VPDB) - most likely resulting from methanogenesis. Ancillary measurements (pH and cations) were used to determine that no fossil CaCO(3), for instance limestone, biased the analytical conclusions. Radiocarbon analysis is verified as a viable and definitive technique for confirming fossil hydrocarbon conversion to CO(2) (complete oxidation) at hydrocarbon-contaminated groundwater sites. The technique should also be very useful for assessing the efficacy of engineered remediation efforts and by using CO(2) production rates, contaminant mass conversion over time and per unit volume.

  9. Acetylene fuel from atmospheric CO2 on Mars

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Linne, Diane L.

    1992-01-01

    The Mars mission scenario proposed by Baker and Zubrin (1990) intended for an unmanned preliminary mission is extended to maximize the total impulse of fuel produced with a minimum mass of hydrogen from Earth. The hydrogen along with atmospheric carbon dioxide is processed into methane and oxygen by the exothermic reaction in an atmospheric processing module. Use of simple chemical reactions to produce acetylene/oxygen rocket fuel on Mars from hydrogen makes it possible to produce an amount of fuel that is nearly 100 times the mass of hydrogen brought from earth. If such a process produces the return propellant for a manned Mars mission, the required mission mass in LEO is significantly reduced over a system using all earth-derived propellants.

  10. Global, Regional, and National Fossil-Fuel CO2 Emissions

    DOE Data Explorer

    Boden, T. A.; Andres, R. J.; Marland, G.

    2016-01-01

    The 1950 to present CO2 emission estimates are derived primarily from energy statistics published by the United Nations (2016), using the methods of Marland and Rotty (1984). The energy statistics were compiled primarily from annual questionnaires distributed by the U.N. Statistical Office and supplemented by official national statistical publications. As stated in the introduction of the Statistical Yearbook, "in a few cases, official sources are supplemented by other sources and estimates, where these have been subjected to professional scrutiny and debate and are consistent with other independent sources." Data from the U.S. Department of Interior's Geological Survey (USGS 2016) were used to estimate CO2 emitted during cement production. Values for emissions from gas flaring were derived primarily from U.N. data but were supplemented with data from the U.S. Department of Energy's Energy Information Administration (1994), Rotty (1974), and data provided by G. Marland. Greater details about these methods are provided in Marland and Rotty (1984), Boden et al. (1995), and Andres et al. (1999).

  11. Global, Regional, and National Fossil-Fuel CO2 Emissions

    DOE Data Explorer

    Boden, T. A.; Andres, R. J.; Marland, G.

    2017-01-01

    The 1950 to present CO2 emission estimates are derived primarily from energy statistics published by the United Nations (2017), using the methods of Marland and Rotty (1984). The energy statistics were compiled primarily from annual questionnaires distributed by the U.N. Statistical Office and supplemented by official national statistical publications. As stated in the introduction of the Statistical Yearbook, "in a few cases, official sources are supplemented by other sources and estimates, where these have been subjected to professional scrutiny and debate and are consistent with other independent sources." Data from the U.S. Department of Interior's Geological Survey (USGS 2017) were used to estimate CO2 emitted during cement production. Values for emissions from gas flaring were derived primarily from U.N. data but were supplemented with data from the U.S. Department of Energy's Energy Information Administration (1994), Rotty (1974), and data provided by G. Marland. Greater details about these methods are provided in Marland and Rotty (1984), Boden et al. (1995), and Andres et al. (1999).

  12. Global, Regional, and National Fossil-Fuel CO2 Emissions

    DOE Data Explorer

    Boden, T. A.; Andres, R. J.; Marland, G.

    2015-01-01

    The 1950 to present CO2 emission estimates are derived primarily from energy statistics published by the United Nations (2014), using the methods of Marland and Rotty (1984). The energy statistics were compiled primarily from annual questionnaires distributed by the U.N. Statistical Office and supplemented by official national statistical publications. As stated in the introduction of the Statistical Yearbook, "in a few cases, official sources are supplemented by other sources and estimates, where these have been subjected to professional scrutiny and debate and are consistent with other independent sources." Data from the U.S. Department of Interior's Geological Survey (USGS 2014) were used to estimate CO2 emitted during cement production. Values for emissions from gas flaring were derived primarily from U.N. data but were supplemented with data from the U.S. Department of Energy's Energy Information Administration (1994), Rotty (1974), and data provided by G. Marland. Greater details about these methods are provided in Marland and Rotty (1984), Boden et al. (1995), and Andres et al. (1999).

  13. Towards space/time resolved uncertainty quantification of urban fossil fuel CO2 emissions (Invited)

    NASA Astrophysics Data System (ADS)

    Gurney, K. R.; Razlivanov, I. N.; Patarasuk, R.; Song, Y.; O'Keeffe, D.; Huang, J.

    2013-12-01

    Quantification of fossil fuel CO2 emissions from the bottom-up perspective is a critical element in emerging plans on a global, integrated, carbon monitoring system (CMS). A space/time explicit emissions data product can act as both a verification and planning system. It can verify atmospheric CO2 measurements (in situ and remote) and offer detailed mitigation information to management authorities in order to optimize the mix of mitigation efforts. Quantification of the uncertainty associated with bottom-up emission data products remains a challenging endeavor. There are a number of reasons for this. First, bottom-up source data is often produced by a regulatory agency, which has strict legal limits to the amount and type of information available. Even in cases where legal limitations are not at work, there is no standard for uncertainty reporting and hence, little reliable uncertainty estimation is made. The Hestia Project is an effort aimed at building high-resolution (eg. building and road link-specific, hourly) fossil fuel CO2 emissions data products at the scale of buildings/street segments for entire urban domains. A complete data product has been built for the city of Indianapolis and preliminary quantification has been completed for Los Angeles and Salt Lake City. The effort in Indianapolis is now part of a larger effort aimed at a convergent top-down/bottom-up assessment of greenhouse gas emissions, called INFLUX. In the course of this work, we have attempted to quantify uncertainty. In some cases, this is driven by parameter sensitivity, in other cases through the comparison of independent datasets reporting on the same entity. Expert judgment is also deployed where no alternative exists. Here, I will provide a review of some of these techniques with examples from our urban case studies. Total fossil fuel CO2 emissions for Marion County, IN, for the year 2002: (a) top view with numbered zones and (b) blowups of the numbered zones. Color units: log10 kg C

  14. Perspective: Photocatalytic reduction of CO2 to solar fuels over semiconductors

    NASA Astrophysics Data System (ADS)

    Peng, Chao; Reid, Glenn; Wang, Haifeng; Hu, P.

    2017-07-01

    Increasing emissions of carbon dioxide and the depletion of finite fossil fuels have led to many concerns about global warming and energy crises. Consequently, a sustainable and alternative method, photocatalytic CO2 reduction to chemical fuels has received considerable attention. This perspective highlights recent knowledge and the main challenges in CO2 photoreduction primarily from the theoretical field. The fundamental understanding of CO2 adsorption and reaction mechanism at an atomic level is fully addressed, and the relevant effects dominating the process of CO2 photoreduction are also elucidated. Moreover, recent development of photocatalysts including structural modification is presented, which greatly affects the efficiency and selectivity of CO2 conversion. Finally, the possibilities and challenges in this field are discussed.

  15. Graphene-Based Photocatalysts for CO2 Reduction to Solar Fuel.

    PubMed

    Low, Jingxiang; Yu, Jiaguo; Ho, Wingkei

    2015-11-05

    Recently, photocatalytic CO2 reduction for solar fuel production has attracted much attention because of its potential for simultaneously solving energy and global warming problems. Many studies have been conducted to prepare novel and efficient photocatalysts for CO2 reduction. Graphene, a two-dimensional material, has been increasingly used in photocatalytic CO2 reduction. In theory, graphene shows several remarkable properties, including excellent electronic conductivity, good optical transmittance, large specific surface area, and superior chemical stability. Attributing to these advantages, fabrication of graphene-based materials has been known as one of the most feasible strategies to improve the CO2 reduction performance of photocatalysts. This Perspective mainly focuses on the recent important advances in the fabrication and application of graphene-based photocatalysts for CO2 reduction to solar fuels. The existing challenges and difficulties of graphene-based photocatalysts are also discussed for future application.

  16. Perspective: Photocatalytic reduction of CO2 to solar fuels over semiconductors.

    PubMed

    Peng, Chao; Reid, Glenn; Wang, Haifeng; Hu, P

    2017-07-21

    Increasing emissions of carbon dioxide and the depletion of finite fossil fuels have led to many concerns about global warming and energy crises. Consequently, a sustainable and alternative method, photocatalytic CO2 reduction to chemical fuels has received considerable attention. This perspective highlights recent knowledge and the main challenges in CO2 photoreduction primarily from the theoretical field. The fundamental understanding of CO2 adsorption and reaction mechanism at an atomic level is fully addressed, and the relevant effects dominating the process of CO2 photoreduction are also elucidated. Moreover, recent development of photocatalysts including structural modification is presented, which greatly affects the efficiency and selectivity of CO2 conversion. Finally, the possibilities and challenges in this field are discussed.

  17. The first 1-year-long estimate of the Paris region fossil fuel CO2 emissions based on atmospheric inversion

    NASA Astrophysics Data System (ADS)

    Staufer, Johannes; Broquet, Grégoire; Bréon, François-Marie; Puygrenier, Vincent; Chevallier, Frédéric; Xueref-Rémy, Irène; Dieudonné, Elsa; Lopez, Morgan; Schmidt, Martina; Ramonet, Michel; Perrussel, Olivier; Lac, Christine; Wu, Lin; Ciais, Philippe

    2016-11-01

    The ability of a Bayesian atmospheric inversion to quantify the Paris region's fossil fuel CO2 emissions on a monthly basis, based on a network of three surface stations operated for 1 year as part of the CO2-MEGAPARIS experiment (August 2010-July 2011), is analysed. Differences in hourly CO2 atmospheric mole fractions between the near-ground monitoring sites (CO2 gradients), located at the north-eastern and south-western edges of the urban area, are used to estimate the 6 h mean fossil fuel CO2 emission. The inversion relies on the CHIMERE transport model run at 2 km × 2 km horizontal resolution, on the spatial distribution of fossil fuel CO2 emissions in 2008 from a local inventory established at 1 km × 1 km horizontal resolution by the AIRPARIF air quality agency, and on the spatial distribution of the biogenic CO2 fluxes from the C-TESSEL land surface model. It corrects a prior estimate of the 6 h mean budgets of the fossil fuel CO2 emissions given by the AIRPARIF 2008 inventory. We found that a stringent selection of CO2 gradients is necessary for reliable inversion results, due to large modelling uncertainties. In particular, the most robust data selection analysed in this study uses only mid-afternoon gradients if wind speeds are larger than 3 m s-1 and if the modelled wind at the upwind site is within ±15° of the transect between downwind and upwind sites. This stringent data selection removes 92 % of the hourly observations. Even though this leaves few remaining data to constrain the emissions, the inversion system diagnoses that their assimilation significantly reduces the uncertainty in monthly emissions: by 9 % in November 2010 to 50 % in October 2010. The inverted monthly mean emissions correlate well with independent monthly mean air temperature. Furthermore, the inverted annual mean emission is consistent with the independent revision of the AIRPARIF inventory for the year 2010, which better corresponds to the measurement period than the 2008

  18. Quantification of fossil fuel CO2 emissions at the building/street scale for a large US city

    SciTech Connect

    Gurney, Kevin R.; Razlivanov, I.; Song, Yang; Zhou, Yuyu; Benes, Bedrich; Abdul- Massih, Michel

    2012-08-15

    In order to advance the scientific understanding of carbon exchange with the land surface, build an effective carbon monitoring system and contribute to quantitatively-based U.S. climate change policy interests, fine spatial and temporal quantification of fossil fuel CO2 emissions, the primary greenhouse gas, is essential. Called the ‘Hestia Project’, this research effort is the first to use bottom-up methods to quantify all fossil fuel CO2 emissions down to the scale of individual buildings, road segments, and industrial/electricity production facilities on an hourly basis for an entire urban landscape. a large city (Indianapolis, Indiana USA). Here, we describe the methods used to quantify the on-site fossil fuel CO2 emissions across the city of Indianapolis, Indiana. This effort combines a series of datasets and simulation tools such as a building energy simulation model, traffic data, power production reporting and local air pollution reporting. The system is general enough to be applied to any large U.S. city and holds tremendous potential as a key component of a carbon monitoring system in addition to enabling efficient greenhouse gas mitigation and planning. We compare our estimate of fossil fuel emissions from natural gas to consumption data provided by the local gas utility. At the zip code level, we achieve a bias adjusted pearson r correlation value of 0.92 (p<0.001).

  19. Tracing fossil fuel CO2 using Δ14C in Xi'an City, China

    NASA Astrophysics Data System (ADS)

    Zhou, Weijian; Wu, Shugang; Huo, Wenwen; Xiong, Xiaohu; Cheng, Peng; Lu, Xuefeng; Niu, Zhenchuan

    2014-09-01

    Radiocarbon can be used to trace fossil fuel CO2 (CO2ff) in the atmosphere, because radiocarbon has been depleted in fossil fuels. Here we present our study on the spatial distribution and temporal variations of CO2ff in Xi'an City, China using Δ14C of both green foxtail (Setaria viridis, L. Beauv.) leaf samples and urban air samples collected in the recent years. Our results show that the CO2ff indicated by green foxtail ranged from 14.7 ± 1.7 to 52.6 ± 1.7 ppm, reflecting high CO2ff mole fractions in downtown, industrial areas, and at road sites, and low CO2ff mole fractions in public parks. Meanwhile, the monthly CO2ff reflected by air samples showed higher value in winter (57.8 ± 17.1 ppm) than that in summer (20.2 ± 9.8 ppm) due to the enhancement usage of coal burning and the poor dispersion condition of atmosphere. This study displays that the increased fossil fuel emission is associated with the fast development of Xi'an City in China. It is worth mentioning that the green foxtail samples can be used to map out the CO2ff spatial distribution on large scale quickly and conveniently, while the air samples can be used to trace the CO2ff temporal variations with high resolution effectively. Therefore the Δ14C of both green foxtail and air samples is a good indicator of CO2ff emission.

  20. Biofuels from Bacteria, Electricity, and CO2: Biofuels from CO2 Using Ammonia or Iron-Oxidizing Bacteria in Reverse Microbial Fuel Cells

    SciTech Connect

    2010-07-01

    Electrofuels Project: Electrofuels Project: Columbia University is using carbon dioxide (CO2) from ambient air, ammonia—an abundant and affordable chemical, and a bacteria called N. europaea to produce liquid fuel. The Columbia University team is feeding the ammonia and CO2 into an engineered tank where the bacteria live. The bacteria capture the energy from ammonia and then use that energy to convert CO2 into a liquid fuel. When the bacteria use up all the ammonia, renewable electricity can regenerate it and pump it back into the system—creating a continuous fuel-creation cycle. In addition, Columbia University is also working with the bacteria A. ferrooxidans to capture and use energy from ferrous iron to produce liquid fuels from CO2.

  1. Geophysical monitoring of near surface CO2 injection at Svelvik - Learnings from the CO2FieldLab experiments.

    NASA Astrophysics Data System (ADS)

    Querendez, Etor; Romdhane, Anouar; Jordan, Michael; Eliasson, Peder; Grimstad, Alv-Arne

    2014-05-01

    A CO2 migration field laboratory for testing monitoring methods and tools has been established in the glaciofluvial-glaciomarine Holocene deposits of the Svelvik ridge, near Oslo (Norway). At the site, feasibility, sensitivity, acquisition geometry and usefulness of various surface and subsurface monitoring tools are investigated during controlled CO2 injection experiments. In a first stage, a shallow CO2 injection experiment was conducted in September 2011. Approximately 1700 kg of CO2 was injected at 18 m depth below surface in an unconsolidated sand formation. The objectives of this experiment were to (i) detect and, where possible, quantify migrated CO2 concentrations at the surface and very shallow subsurface, (ii) evaluate the sensitivity of the monitoring tools and (iii) study the impact of the vadose zone on observed measurements. Results showed that all deployed monitoring tools (for surface and near-surface gas monitoring, subsurface water monitoring and subsurface geophysical monitoring) where able to detect the presence of CO2 even though the CO2 plume did not migrate vertically as expected in what was thought to be an homogeneous unconsolidated sand structure. The upper part of the site revealed to be more heterogeneous than expected, mainly due to the highly variable lamination and channelling of the morainic sediments and to the presence of pebble and cobble beds sporadically showing throughout the deposits. Building on the learnings from the 18m depth injection experiment, a second experiment is being planned for a deeper injection, at a depth of 65m. Re-processing of the appraisal 2D multi-channel seismic with state-of-the-art processing techniques, like Linear Radon coherent and random noise attenuation and Full Waveform Inversion followed by pre-stack depth migration, corroborate the presence of heterogeneities at the near surface. Based on the re-interpreted seismic sections, a more realistic 3D geomodel, where the complex topography of the site

  2. Quantification of space/time explicit fossil fuel CO2 emissions in urban domains

    NASA Astrophysics Data System (ADS)

    Gurney, K. R.; Razlivanov, I. N.; Song, Y.

    2013-05-01

    Quantification of fossil fuel CO2 emissions from the bottom-up perspective is a critical element in development of a carbon monitoring system. A space/time explicit emissions data product can verify atmospheric CO2 measurements and offer practical information to authorities in order to optimize mitigation efforts. Here, we present the Hestia Project, an effort aimed at building a high resolution (eg. building and road link-specific, hourly) fossil fuel CO2 emissions data product for the urban domain. A complete data product has been built for the city of Indianapolis and work is ongoing in Los Angeles. The work in Indianapolis is now part of a larger effort, INFLUX, aimed at a convergent top-down/bottom-up assessment of greenhouse gas emissions. The work in Los Angeles with JPL colleagues is aimed at building an operational carbon monitoring system with focus on global megacities. Our urban-level quantification relies on a mixture of data and modeling structures. We start with the sector-specific Vulcan Project estimate using Hestia to distribute emissions in space and time. Two components take the majority of effort: buildings and onroad emissions. For the buildings, we utilize an energy building model constrained with multiple local data streams. For onroad emissions, we use a combination of traffic data and GIS road layers maintaining vehicle class information. In collaboration with our INFLUX colleagues, we are transporting these high resolution emissions through an atmospheric transport model for a forward comparison of the Hestia data product with atmospheric measurements, collected on aircraft and cell towers. In collaboration with our JPL colleagues, we are testing the feasibility of quantifying a megacity domain and how it might integrate with remote sensing and in situ measurement systems. The Hestia effort also holds promise for a useable policy tool at the city scale. With detailed information on energy consumption and emissions with process

  3. Liquid Fuel From Bacteria: Engineering Ralstonia eutropha for Production of Isobutanol (IBT) Motor Fuel from CO2, Hydrogen, and Oxygen

    SciTech Connect

    2010-07-15

    Electrofuels Project: MIT is using solar-derived hydrogen and common soil bacteria called Ralstonia eutropha to turn carbon dioxide (CO2) directly into biofuel. This bacteria already has the natural ability to use hydrogen and CO2 for growth. MIT is engineering the bacteria to use hydrogen to convert CO2 directly into liquid transportation fuels. Hydrogen is a flammable gas, so the MIT team is building an innovative reactor system that will safely house the bacteria and gas mixture during the fuel-creation process. The system will pump in precise mixtures of hydrogen, oxygen, and CO2, and the online fuel-recovery system will continuously capture and remove the biofuel product.

  4. Thermocatalytic CO2-Free Production of Hydrogen from Hydrocarbon Fuels

    SciTech Connect

    University of Central Florida

    2004-01-30

    The main objective of this project is the development of an economically viable thermocatalytic process for production of hydrogen and carbon from natural gas or other hydrocarbon fuels with minimal environmental impact. The three major technical goals of this project are: (1) to accomplish efficient production of hydrogen and carbon via sustainable catalytic decomposition of methane or other hydrocarbons using inexpensive and durable carbon catalysts, (2) to obviate the concurrent production of CO/CO{sub 2} byproducts and drastically reduce CO{sub 2} emissions from the process, and (3) to produce valuable carbon products in order to reduce the cost of hydrogen production The important feature of the process is that the reaction is catalyzed by carbon particulates produced in the process, so no external catalyst is required (except for the start-up operation). This results in the following advantages: (1) no CO/CO{sub 2} byproducts are generated during hydrocarbon decomposition stage, (2) no expensive catalysts are used in the process, (3) several valuable forms of carbon can be produced in the process depending on the process conditions (e.g., turbostratic carbon, pyrolytic graphite, spherical carbon particles, carbon filaments etc.), and (4) CO{sub 2} emissions could be drastically reduced (compared to conventional processes).

  5. CO2-water-mineral reactions during CO2 leakage into glauconitic sands: geochemical and isotopic monitoring of batch experiments

    NASA Astrophysics Data System (ADS)

    Humez, P.; Lions, J.; Lagneau, V.; Negrel, Ph.

    2012-04-01

    The assessment of environmental impacts of carbon dioxide geological storage requires the investigation of the potential CO2 leakages into fresh groundwater reserves. The Albian aquifer of the Paris Basin was chosen as a case of study because i) the Paris Basin contains deep saline Jurassic and Triassic aquifers identified as targets by the French national program of CO2 geological storage and ii) the Albian aquifer is a deep freshwater resource of strategic national importance, above the Jurassic and Triassic formations. An experimental and a geochemical modelling approach were carried out in order to better understand the rock-water-CO2 interactions with two main objectives: to assess the evolution of the chemistry of the formation water and of the mineralogy of the solid phase during the interaction and to design a monitoring program for freshwater resources. The main focus is to select and develop suitable indirect indicators of the presence of CO2 in the aquifer. We present here the experimental results, which combines both major and trace elements and isotopic tools, some of them new in the CCS field. Batch reactors with a liquid/solid ratio of 10 made of appropriate materials (PTFE, stainless steel) were equipped with simultaneous controls on several parameters (pH measurement, gas phase composition, pressure, tightness…) after CO2 injection (PCO2= 2 bar; room temperature). Ten reactors were run simultaneously, over pre-determined durations of CO2-water-rock interaction (1, 7, 15 and 30 days). During the batch experiment, we observed major changes in several chemical parameters due to the CO2 injection. A sharp drop in pH from 6.6 to 4.9 was noticeable, immediately after the injection, due to CO2 dissolution in the water phase. Alkalinity varies from 1.3 mmol.L-1 in the initial water to 2.0 mmol.L-1 at the end of the 1-month experiment. Four types of ion behaviors are observed: (1) calcium, silicon and magnesium concentrations increase during the 1-month

  6. Hydrological and geochemical monitoring for a CO2 sequestration pilot in a brine formation

    SciTech Connect

    Doughty, Christine; Pruess, Karsten; Benson, Sally M.; Freifeld, Barry M.; Gunter, William D.

    2004-05-17

    Hydrological and geochemical monitoring are key components of site characterization and CO2 plume monitoring for a pilot test to inject CO2 into a brine-bearing sand of the fluvial-deltaic Frio formation in the upper Texas Gulf Coast. In situ, injected CO2 forms a supercritical phase that has gas-like properties (low density and viscosity) compared to the surrounding brine, while some CO2 dissolves in the brine. The pilot test employs one injection well and one monitor well, with continuous pressure and flow-rate monitoring in both wells, and continuous surface fluid sampling and periodic down-hole fluid sampling from the monitor well. Pre-injection site-characterization includes pump tests with pressure-transient analysis to estimate single-phase flow properties, establish hydraulic connectivity between the wells, determine appropriate boundary conditions, and analyze ambient phase conditions within the formation. Additionally, a pre-injection tracer test furnishes estimates of kinematic porosity and the geometry of flow paths between injection and monitor wells under single-phase conditions. Pre-injection geochemical sampling provides a baseline for subsequent geochemical monitoring and helps determine the optimal tracers to accompany CO2 injection. During CO2 injection, hydrological monitoring enables estimation of two-phase flow properties and helps track the movement of the injected CO2 plume, while geochemical sampling provides direct evidence of the arrival of CO2 and tracers at the monitor well. Furthermore, CO2-charged water acts as a weak acid, and reacts to some extent with the minerals in the aquifer, producing a distinct chemical signature in the water collected at the monitor well. Comparison of breakthrough curves for the single-phase tracer test and the CO2 (and its accompanying tracers) illuminates two-phase flow processes between the supercritical CO2 and native brine, an area of current uncertainty that must be better understood to effectively

  7. Atmospheric Fossil Fuel CO2 Tracing By 14C In Some Chinese Cities

    NASA Astrophysics Data System (ADS)

    Zhou, W.; Niu, Z.; Zhu, Y., Sr.

    2016-12-01

    CO2 plays an important role in global climate as a primary greenhouse gas in the atmosphere. Moreover, it has been shown that more than 70% of global fossil fuel CO2 (CO2ff) emissions are concentrated in urban areas (Duren and Miller, 2012). Our study focuses on atmospheric CO2ff concentrations in 15 Chinese cities using accelerator mass spectrometer (AMS) to measure 14C. Our objectives are: (1) to document atmospheric CO2ff concentrations in a variety of urban environments, (2) to differentiate the spatial-temporal variations in CO2ff among these cities, and (3) to ascertain the factors that control the observed variations. For about two years (winter 2014 to winter 2016), the CO2ff concentrations we observed from all sites varied from 5.1±4.5 ppm to 65.8±39.0 ppm. We observed that inland cities display much higher CO2ff concentrations and overall temporal variations than coastal cities in winter, and that northern cities have higher CO2ff concentrations than those of southern cities in winter. For inland cities relatively high CO2ff values are observed in winter and low values in summer; while seasonal variations are not distinct in the coastal cities. No significant (p > 0.05) differences in CO2ff values are found between weekdays and weekends as was shown previously in Xi'an (Zhou et al., 2014). Diurnal CO2ff variations are plainly evident, with high values between midnight and 4:00 am, and during morning and afternoon rush hours (Niu et al., 2016). The high CO2ff concentrations in northern inland cities in winter results mainly from the substantial consumption of fossil fuels for heating. The high CO2ff concentrations seen in diurnal measurements result mainly from variations in atmospheric dispersion, and from vehicle emissions related to traffic flows. The inter-annual variations in CO2ff in cities could provide a useful reference for local governments to develop policy around the effect of energy conservation and emission reduction strategies.

  8. Photocatalytic conversion of CO2 into value-added and renewable fuels

    NASA Astrophysics Data System (ADS)

    Yuan, Lan; Xu, Yi-Jun

    2015-07-01

    The increasing energy crisis and the worsening global climate caused by the excessive utilization of fossil fuel have boosted tremendous research activities about CO2 capture, storage and utilization. Artificial photosynthesis that uses solar light energy to convert CO2 to form value-added and renewable fuels such as methane or methanol has been consistently drawing increasing attention. It is like killing two birds with one stone since it can not only reduce the greenhouse effects caused by CO2 emission but also produce value added chemicals for alternative energy supplying. This review provides a brief introduction about the basic principles of artificial photosynthesis of CO2 and the progress made in exploring more efficient photocatalysts from the viewpoint of light harvesting and photogenerated charge carriers boosting. Moreover, the undergoing mechanisms of CO2 photoreduction are discussed with selected examples, in terms of adsorption of reactants, CO2 activation as well as the possible reaction pathways. Finally, perspectives on future research directions and open issues in CO2 photoreduction are outlined.

  9. Organic reactions for the electrochemical and photochemical production of chemical fuels from CO2--The reduction chemistry of carboxylic acids and derivatives as bent CO2 surrogates.

    PubMed

    Luca, Oana R; Fenwick, Aidan Q

    2015-11-01

    The present review covers organic transformations involved in the reduction of CO2 to chemical fuels. In particular, we focus on reactions of CO2 with organic molecules to yield carboxylic acid derivatives as a first step in CO2 reduction reaction sequences. These biomimetic initial steps create opportunities for tandem electrochemical/chemical reductions. We draw parallels between long-standing knowledge of CO2 reactivity from organic chemistry, organocatalysis, surface science and electrocatalysis. We point out some possible non-faradaic chemical reactions that may contribute to product distributions in the production of solar fuels from CO2. These reactions may be accelerated by thermal effects such as resistive heating and illumination.

  10. Monitoring CO2 injection with a buried geophone array: Stage 2C of CO2CRC Otway Project

    NASA Astrophysics Data System (ADS)

    Urosevic, M.; Gurevich, B.; Pevzner, R.; Tertyshnikov, K.; Shulakova, V.; Glubokovskikh, S.; Popik, D.; Kepic, A.; Robertson, M.; Freifeld, B. M.; Daley, T. M.; Singh, R.

    2015-12-01

    The Stage 2 of the CO2CRC project involves injection of a small quantity of CO2, 15 Kt, into the Paaratte formation, a saline aquifer located at a depth of around 1500 m in the Otway basin, Victoria, Australia. The project aims to investigate the limits of time lapse seismic methodologies in order to devise an optimal monitoring program. That includes time lapse signal and noise prediction, time lapse data acquisition design and finally data analysis. The strength of the time lapse (TL) seismic is governed by the magnitudes of both the time lapse signal and time lapse noise. They are in turn both dependent on numerous factors which need to be addressed through modelling studies and data acquisition technologies. Geological information is used to build a detailed 3D static model for the dynamic reservoir simulations and analysis of CO2 plume distribution for small quantities of CO2 injected into the deepest Paaratte member. Various lithological scenarios and variations in permeability distribution are tested until arriving at the "most likely" solution. The final model is used initially for 1D and subsequently for the full 3D time lapse modelling. These time lapse modelling results, combined with field tests and noise analysis, show clearly that small quantities of CO2 injected into a relatively thin (~20 m in thickness) saline aquifer would benefit from utilizing a permanent 3D seismic array to achieve desired repeatability, that is reduction in time lapse seismic noise. Buried receiver array was designed and deployed at the CO2CRC Otway during January and February. The array comprises 908 high-sensitivity geophones deployed at 4 m depth below the surface. Baseline 3D was acquired in March 2015. Some 3003 shots were acquired by a crew of 7 people over 9 days. Benchmark tests show a significant improvement in data quality compared to surface geophones. With this approach there are no cables or other seismic infrastructure on the surface. This significantly reduces

  11. Delivery room end tidal CO2 monitoring in preterm infants <32 weeks.

    PubMed

    Hawkes, Gavin A; Kenosi, Mmoloki; Finn, Daragh; O'Toole, John M; O'Halloran, Ken D; Boylan, Geraldine B; Ryan, Anthony C; Dempsey, Eugene M

    2016-01-01

    To determine the feasibility of end tidal (EtCO2) monitoring of preterm infants in the delivery room, to determine EtCO2 levels during delivery room stabilisation, and to examine the incidence of normocapnia (5-8 kPa) on admission to the neonatal intensive care unit in the EtCO2 monitored group compared with a historical cohort without EtCO2 monitoring. Preterm infants (<32 weeks) were eligible for inclusion in this observational study. The evolution of EtCO2 values immediately after delivery was assessed and linear least-squares methods were used to fit a line to EtCO2 recordings. The partial pressure of CO2 in blood (PCO2) from the infants who received EtCO2 monitoring was compared with a historical cohort without EtCO2 monitoring. EtCO2 monitoring was feasible in the delivery room. EtCO2 values were successfully obtained in 39 (88.7%) of the 44 infants included in the study. EtCO2 gradually increased over the first 4 min. Intubated infants had higher EtCO2 values compared with infants who were not intubated, with median (IQR) values of 4.7 (3.3-8.4) kPa versus 3.2 (2.6-4.2) kPa (p=0.05). No difference was found between the proportions of PCO2 values within the range of normocapnia among infants who received EtCO2 monitoring compared with those who did not (56.8% vs 47.9%, p=0.396). Delivery room EtCO2 monitoring is feasible and safe. EtCO2 values obtained after birth reflect the establishment of functional residual capacity and effective ventilation. The potential short-term and long-term consequences of EtCO2 monitoring should be established in randomised controlled trials. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  12. Combustion Characteristics of Oxy-fuel Burners for CO2 Capturing Boilers

    NASA Astrophysics Data System (ADS)

    Ahn, Joon; Kim, Hyouck Ju; Choi, Kyu Sung

    Oxy-fuel boilers have been developed to capture CO2 from the exhaust gas. A 50 kW class model burner has been developed and tested in a furnace type boiler. The burner has been scaled up to 0.5 and 3 MW class for fire-tube type boilers. The burners are commonly laid out in a coaxial type to effectively heat the combustion chamber of boilers. Burners are devised to support air and oxy-fuel combustion modes for the retrofitting scenario. FGR (flue gas recirculation) has been tried during the scale-up procedure. Oxy-fuel combustion yields stretched flame to uniformly heat the combustion chamber. It also provides the high CO2 concentration, which is over 90% in dry base. However, pure oxy-fuel combustion increases NO concentration, because of the reduced flow rate. The FGR can suppress the thermal NOx induced by the infiltration of the air.

  13. Potential for the Use of Wireless Sensor Networks for Monitoring of CO2 Leakage Risks

    NASA Astrophysics Data System (ADS)

    Pawar, R.; Illangasekare, T. H.; Han, Q.; Jayasumana, A.

    2015-12-01

    Storage of supercritical CO2 in deep saline geologic formation is under study as a means to mitigate potential global climate change from green house gas loading to the atmosphere. Leakage of CO2 from these formations poses risk to the storage permanence goal of 99% of injected CO2 remaining sequestered from the atmosphere,. Leaked CO2 that migrates into overlying groundwater aquifers may cause changes in groundwater quality that pose risks to environmental and human health. For these reasons, technologies for monitoring, measuring and accounting of injected CO2 are necessary for permitting of CO2 sequestration projects under EPA's class VI CO2 injection well regulations. While the probability of leakage related to CO2 injection is thought to be small at characterized and permitted sites, it is still very important to protect the groundwater resources and develop methods that can efficiently and accurately detect CO2 leakage. Methods that have been proposed for leakage detection include remote sensing, soil gas monitoring, geophysical techniques, pressure monitoring, vegetation stress and eddy covariance measurements. We have demonstrated the use of wireless sensor networks (WSN) for monitoring of subsurface contaminant plumes. The adaptability of this technology for leakage monitoring of CO2 through geochemical changes in the shallow subsurface is explored. For this technology to be viable, it is necessary to identify geochemical indicators such as pH or electrical conductivity that have high potential for significant change in groundwater in the event of CO2 leakage. This talk presents a conceptual approach to use WSNs for CO2 leakage monitoring. Based on our past work on the use of WSN for subsurface monitoring, some of the challenges that need to be over come for this technology to be viable for leakage detection will be discussed.

  14. Influence of test fuel properties and composition on UNECE R101 CO2 and fuel economy valuation

    NASA Astrophysics Data System (ADS)

    Parker, A.

    2015-12-01

    CO2 emission and fuel consumption of passenger cars is now assessed by using a simplistic procedure measuring the emission during a test performed without any control of the fuel properties and computing the fuel consumption through an unsophisticated formula. As pump gasoline and diesel fuels are refinery products mixture of many different hydrocarbons, and in case of gasoline may also contain a significant amount of oxygenates, the fuel properties, including the density, carbon and energy content may strongly vary from one pump fuel to the other. Being the specific test fuels carefully selected by the car manufacturers and everything but randomly chosen pump fuels, the claimed CO2 emission and fuel economy figures may differ largely from the certification values. I show from the analysis of the 2014 UK government data for 2358 diesel and 2103 petrol vehicles how same volumes of only theoretically same pump fuels used during the certification test by the cars manufacturers unfortunately do not produce the same carbon dioxide emission, and very likely do not have the same energy content. The CO2 emission per liter of diesel fuel is shown to oscillate froma maximum of 3049 g to a minimum of 2125 g, with an average of 2625 g, froma +16.13% to a -19.06% of the average. TheCO2 emission per liter of petrol fuel is shown to oscillate even more from a maximum of 3735 g to a minimum of 1767 g with an average of 2327 g, from a +60.48% to a -24.05% of the average. The proposed solution is to center the assessment on the energy demand by measuring with accuracy the mass of fuel consumed and the fuel properties of the test fuel starting from the lower heating. The corrected fuel consumption and the corrected carbon dioxide emission to mention from the test are then computed by using pure hydrocarbon reference fuels for diesel and petrol having a given lower heating value and a given hydrocarbon composition. Alternatively, exactly the same test fuel should be used by all the

  15. Independent evaluation of point source fossil fuel CO2 emissions to better than 10.

    PubMed

    Turnbull, Jocelyn Christine; Keller, Elizabeth D; Norris, Margaret W; Wiltshire, Rachael M

    2016-09-13

    Independent estimates of fossil fuel CO2 (CO2ff) emissions are key to ensuring that emission reductions and regulations are effective and provide needed transparency and trust. Point source emissions are a key target because a small number of power plants represent a large portion of total global emissions. Currently, emission rates are known only from self-reported data. Atmospheric observations have the potential to meet the need for independent evaluation, but useful results from this method have been elusive, due to challenges in distinguishing CO2ff emissions from the large and varying CO2 background and in relating atmospheric observations to emission flux rates with high accuracy. Here we use time-integrated observations of the radiocarbon content of CO2 ((14)CO2) to quantify the recently added CO2ff mole fraction at surface sites surrounding a point source. We demonstrate that both fast-growing plant material (grass) and CO2 collected by absorption into sodium hydroxide solution provide excellent time-integrated records of atmospheric (14)CO2 These time-integrated samples allow us to evaluate emissions over a period of days to weeks with only a modest number of measurements. Applying the same time integration in an atmospheric transport model eliminates the need to resolve highly variable short-term turbulence. Together these techniques allow us to independently evaluate point source CO2ff emission rates from atmospheric observations with uncertainties of better than 10%. This uncertainty represents an improvement by a factor of 2 over current bottom-up inventory estimates and previous atmospheric observation estimates and allows reliable independent evaluation of emissions.

  16. Independent evaluation of point source fossil fuel CO2 emissions to better than 10%

    PubMed Central

    Turnbull, Jocelyn Christine; Keller, Elizabeth D.; Norris, Margaret W.; Wiltshire, Rachael M.

    2016-01-01

    Independent estimates of fossil fuel CO2 (CO2ff) emissions are key to ensuring that emission reductions and regulations are effective and provide needed transparency and trust. Point source emissions are a key target because a small number of power plants represent a large portion of total global emissions. Currently, emission rates are known only from self-reported data. Atmospheric observations have the potential to meet the need for independent evaluation, but useful results from this method have been elusive, due to challenges in distinguishing CO2ff emissions from the large and varying CO2 background and in relating atmospheric observations to emission flux rates with high accuracy. Here we use time-integrated observations of the radiocarbon content of CO2 (14CO2) to quantify the recently added CO2ff mole fraction at surface sites surrounding a point source. We demonstrate that both fast-growing plant material (grass) and CO2 collected by absorption into sodium hydroxide solution provide excellent time-integrated records of atmospheric 14CO2. These time-integrated samples allow us to evaluate emissions over a period of days to weeks with only a modest number of measurements. Applying the same time integration in an atmospheric transport model eliminates the need to resolve highly variable short-term turbulence. Together these techniques allow us to independently evaluate point source CO2ff emission rates from atmospheric observations with uncertainties of better than 10%. This uncertainty represents an improvement by a factor of 2 over current bottom-up inventory estimates and previous atmospheric observation estimates and allows reliable independent evaluation of emissions. PMID:27573818

  17. Using the Relationship between Vehicle Fuel Consumption and CO2 Emissions To Illustrate Chemical Principles

    NASA Astrophysics Data System (ADS)

    Oliver-Hoyo, Maria T.; Pinto, Gabriel

    2008-02-01

    This instructional resource utilizes consumer product information by which students compare theoretical stoichiometric calculations to CO 2 car emissions and fuel consumption data. Representing graphically the emission of CO 2 versus consumption of fuel provides a tangible way of connecting concepts studied in chemistry classes to everyday life. Considerable simplification of an otherwise complex chemistry problem provides comparable theoretical and actual data. Practice with unit conversion and graphing enhance this activity promoting skills used by professionals to perform emission measurements. This activity may be used to bring awareness of car emissions issues such as the environmental impact of CO 2 emissions and the differences of hybrid engines or gasoline versus diesel engines. Scientific literacy can be approached by incorporating exercises such as this one into chemistry classroom activities. Students have expressed keen interest in this type of "tangible" chemistry where a concrete example of everyday life puts textbook chemistry in context.

  18. Tracking a Common Surface-Bound Intermediate during CO2-to-Fuels Catalysis

    PubMed Central

    2016-01-01

    Rational design of selective CO2-to-fuels electrocatalysts requires direct knowledge of the electrode surface structure during turnover. Metallic Cu is the most versatile CO2-to-fuels catalyst, capable of generating a wide array of value-added products, including methane, ethylene, and ethanol. All of these products are postulated to form via a common surface-bound CO intermediate. Therefore, the kinetics and thermodynamics of CO adsorption to Cu play a central role in determining fuel-formation selectivity and efficiency, highlighting the need for direct observation of CO surface binding equilibria under catalytic conditions. Here, we synthesize nanostructured Cu films adhered to IR-transparent Si prisms, and we find that these Cu surfaces enhance IR absorption of bound molecules. Using these films as electrodes, we examine Cu-catalyzed CO2 reduction in situ via IR spectroelectrochemistry. We observe that Cu surfaces bind electrogenerated CO, derived from CO2, beginning at −0.60 V vs RHE with increasing surface population at more negative potentials. Adsorbed CO is in dynamic equilibrium with dissolved 13CO and exchanges rapidly under catalytic conditions. The CO adsorption profiles are pH independent, but adsorbed CO species undergo a reversible transformation on the surface in modestly alkaline electrolytes. These studies establish the potential, concentration, and pH dependencies of the CO surface population on Cu, which serve to maintain a pool of this vital intermediate primed for further reduction to higher order fuel products. PMID:27610413

  19. Enhanced carbonate and silicate weathering accelerates recovery from fossil fuel CO2 perturbations

    NASA Astrophysics Data System (ADS)

    Lenton, Timothy M.; Britton, Clare

    2006-09-01

    Increasing atmospheric CO2 and surface temperatures should increase carbonate and silicate weathering rates, directly via warming, and indirectly via the CO2 fertilization effect enhancing plant productivity. Enhanced weathering should in turn increase alkalinity input to the ocean and accelerate long-term CO2 uptake. We added silicate and carbonate weathering and carbonate sediments to an existing global carbon cycle and surface temperature model and subjected it to a range of long-term fossil fuel emissions scenarios, spanning 1100-15,000 GtC in total. Emissions of ≥7350 GtC dissolve all carbonate sediments, and enhanced carbonate and silicate weathering accelerate subsequent CO2 removal from the atmosphere by up to a factor of 4. For 1100-4000 GtC emissions, enhanced weathering accelerates CO2 removal by a factor of 1.5-2.5. However, it takes >1 Myr for silicate weathering to stabilize atmospheric CO2. If land use tends to suppress vegetation and weathering rates on this timescale, then CO2 will stabilize above preindustrial levels.

  20. Feasibility of Autonomous Monitoring of CO2 Leakage in Aquifers: Results From Controlled Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Versteeg, R.; Leger, E.; Dafflon, B.

    2016-12-01

    Geologic sequestration of CO2 is one of the primary proposed approaches for reducing total atmospheric CO2 concentrations. MVAA (Monitoring, Verification, Accounting and Assessment) of CO2 sequestration is an essential part of the geologic CO2 sequestration cycle. MVAA activities need to meet multiple operational, regulatory and environmental objectives, including ensuring the protection of underground sources of drinking water. Anticipated negative consequences of CO2 leakage into groundwater, besides possible brine contamination and release of gaseous CO2, include a significant increase of dissolved CO2 into shallow groundwater systems, which will decrease groundwater pH and can potentially mobilize naturally occurring trace metals and ions that are commonly absorbed to or contained in sediments. Autonomous electrical geophysical monitoring in aquifers has the potential of allowing for rapid and automated detection of CO2 leakage. However, while the feasibility of such monitoring has been demonstrated by a number of different field experiments, automated interpretation of complex electrical resistivity data requires the development of quantitative relationships between complex electrical resistivity signatures and dissolved CO2 in the aquifer resulting from leakage Under a DOE SBIR funded effort we performed multiple tank scale experiments in which we investigated complex electrical resistivity signatures associated with dissolved CO2 plumes in saturated sediments. We also investigated the feasibility of distinguishing CO2 leakage signatures from signatures associated with other processes such as salt water movement, temperature variations and other variations in chemical or physical conditions. In addition to these experiments we also numerically modeled the tank experiments. These experiments showed that (a) we can distinguish CO2 leakage signatures from other signatures, (b) CO2 leakage signatures have a consistent characteristic, (c) laboratory experiments

  1. Core-scale electrical resistivity tomography (ERT) monitoring of CO2-brine mixture in Fontainebleau sandstone

    NASA Astrophysics Data System (ADS)

    Bosch, David; Ledo, Juanjo; Queralt, Pilar; Bellmunt, Fabian; Luquot, Linda; Gouze, Philippe

    2016-07-01

    The main goal of the monitoring stage of Carbon Capture and Storage (CCS) is to obtain an accurate estimation of the subsurface CO2 accumulation and to detect any possible leakage. Laboratory experiments are necessary to investigate the small scale processes governing the CO2-brine-rock interaction. They also provide a means to calibrate the results coming from field scale geophysical methods. In this work we set up an experimental system which is able to perform Electrical Resistivity Tomography (ERT) measurements on centimeter-scale rock samples at various P-T conditions. We present the results of two new experiments related to CO2 monitoring, performed on a cylindrical (4 × 8 cm) Fontainebleau rock sample. In the first one, we have quantified the CO2 saturation at different volume fractions, representing zones from a deep saline aquifer with varying degrees of saturation. In the second one, we have monitored and quantified the effect of CO2 dissolution in the brine at a pressure of 40 bar during eight days, emulating the invasion of CO2 into a shallow aquifer. Results highlight the importance of accounting for the contribution of surface conductivity in highly CO2-saturated regions, even in clay-free rocks, and also for brine conductivity variation due to CO2 dissolution. Ignoring any of these effects will end up in a CO2 saturation underestimation. We present a modified CO2 saturation equation to account for these two influences.

  2. Observations of Atmospheric Δ(14)CO2 at the Global and Regional Background Sites in China: Implication for Fossil Fuel CO2 Inputs.

    PubMed

    Niu, Zhenchuan; Zhou, Weijian; Cheng, Peng; Wu, Shugang; Lu, Xuefeng; Xiong, Xiaohu; Du, Hua; Fu, Yunchong

    2016-11-15

    Six months to more than one year of atmospheric Δ(14)CO2 were measured in 2014-2015 at one global background site in Waliguan (WLG) and four regional background sites at Shangdianzi (SDZ), Lin'an (LAN), Longfengshan (LFS) and Luhuitou (LHT), China. The objectives of the study are to document the Δ(14)CO2 levels at each site and to trace the variations in fossil fuel CO2 (CO2ff) inputs at regional background sites. Δ(14)CO2 at WLG varied from 7.1 ± 2.9‰ to 32.0 ± 3.2‰ (average 17.1 ± 6.8‰) in 2015, with high values generally in autumn/summer and low values in winter/spring. During the same period, Δ(14)CO2 values at the regional background sites were found to be significantly (p < 0.05) lower than those at WLG, indicating different levels of CO2ff inputs at those sites. CO2ff concentrations at LAN (12.7 ± 9.6 ppm) and SDZ (11.5 ± 8.2 ppm) were significantly (p < 0.05) higher than those at LHT (4.6 ± 4.3 ppm) in 2015. There were no significant (p > 0.05) seasonal differences in CO2ff concentrations for the regional sites. Regional sources contributed in part to the CO2ff inputs at LAN and SDZ, while local sources dominated the trend observed at LHT. These data provide a preliminary understanding of atmospheric Δ(14)CO2 and CO2ff inputs for a range of Chinese background sites.

  3. CO2 capture from simulated fuel gas mixtures using semiclathrate hydrates formed by quaternary ammonium salts.

    PubMed

    Park, Sungwon; Lee, Seungmin; Lee, Youngjun; Seo, Yongwon

    2013-07-02

    In order to investigate the feasibility of semiclathrate hydrate-based precombustion CO2 capture, thermodynamic, kinetic, and spectroscopic studies were undertaken on the semiclathrate hydrates formed from a fuel gas mixture of H2 (60%) + CO2 (40%) in the presence of quaternary ammonium salts (QASs) such as tetra-n-butylammonium bromide (TBAB) and fluoride (TBAF). The inclusion of QASs demonstrated significantly stabilized hydrate dissociation conditions. This effect was greater for TBAF than TBAB. However, due to the presence of dodecahedral cages that are partially filled with water molecules, TBAF showed a relatively lower gas uptake than TBAB. From the stability condition measurements and compositional analyses, it was found that with only one step of semiclathrate hydrate formation with the fuel gas mixture from the IGCC plants, 95% CO2 can be enriched in the semiclathrate hydrate phase at room temperature. The enclathration of both CO2 and H2 in the cages of the QAS semiclathrate hydrates and the structural transition that results from the inclusion of QASs were confirmed through Raman and (1)H NMR measurements. The experimental results obtained in this study provide the physicochemical background required for understanding selective partitioning and distributions of guest gases in the QAS semiclathrate hydrates and for investigating the feasibility of a semiclathrate hydrate-based precombustion CO2 capture process.

  4. 40 CFR 75.13 - Specific provisions for monitoring CO2 emissions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...” shall apply rather than “SO2 continuous emission monitoring system,” the phrase “CO2 concentration” shall apply rather than “SO2 concentration,” the term “maximum potential concentration of CO2” shall apply rather than “maximum potential concentration of SO2,” and the phrase “CO2 mass emissions”...

  5. 40 CFR 75.13 - Specific provisions for monitoring CO2 emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...” shall apply rather than “SO2 continuous emission monitoring system,” the phrase “CO2 concentration” shall apply rather than “SO2 concentration,” the term “maximum potential concentration of CO2” shall apply rather than “maximum potential concentration of SO2,” and the phrase “CO2 mass emissions”...

  6. Effective CO2 sequestration monitoring using joint inversion result of seismic and electromagnetic data

    NASA Astrophysics Data System (ADS)

    Noh, K.; Jeong, S.; Seol, S. J.; Byun, J.; Kwon, T.

    2015-12-01

    Man-made carbon dioxide (CO2) released into the atmosphere is a significant contributor to the greenhouse gas effect and related global warming. Sequestration of CO2 into saline aquifers has been proposed as one of the most practical options of all geological sequestration possibilities. During CO2 geological sequestration, monitoring is indispensable to delineate the change of CO2 saturation and migration of CO2 in the subsurface. Especially, monitoring of CO2 saturation in aquifers provides useful information for determining amount of injected CO2. Seismic inversion can provide the migration of CO2 plume with high resolution because velocity is reduced when CO2 replaces the pore fluid during CO2 injection. However, the estimation of CO2 saturation using the seismic method is difficult due to the lower sensitivity of the velocity to the saturation when the CO2 saturation up to 20%. On the other hand, marine controlled-source EM (mCSEM) inversion is sensitive to the resistivity changes resulting from variations in CO2 saturation, even though it has poor resolution than seismic method. In this study, we proposed an effective CO2 sequestration monitoring method using joint inversion of seismic and mCSEM data based on a cross-gradient constraint. The method was tested with realistic CO2 injection models in a deep brine aquifer beneath a shallow sea which is selected with consideration for the access convenience for the installation of source and receiver and an environmental safety. Resistivity images of CO2 plume by the proposed method for different CO2 injection stages have been significantly improved over those obtained from individual EM inversion. In addition, we could estimate a reliable CO2 saturation by rock physics model (RPM) using the P-wave velocity and the improved resistivity. The proposed method is a basis of three-dimensional estimation of reservoir parameters such as porosity and fluid saturation, and the method can be also applied for detecting a

  7. Near-Surface CO2 Monitoring And Analysis To Detect Hidden Geothermal Systems

    SciTech Connect

    Lewicki, Jennifer L.; Oldenburg, Curtis M.

    2005-01-19

    ''Hidden'' geothermal systems are systems devoid of obvious surface hydrothermal manifestations. Emissions of moderate-to-low solubility gases may be one of the primary near-surface signals from these systems. We investigate the potential for CO2 detection and monitoring below and above ground in the near-surface environment as an approach to exploration targeting hidden geothermal systems. We focus on CO2 because it is the dominant noncondensible gas species in most geothermal systems and has moderate solubility in water. We carried out numerical simulations of a CO2 migration scenario to calculate the magnitude of expected fluxes and concentrations. Our results show that CO2 concentrations can reach high levels in the shallow subsurface even for relatively low geothermal source CO2 fluxes. However, once CO2 seeps out of the ground into the atmospheric surface layer, winds are effective at dispersing CO2 seepage. In natural ecological systems in the absence of geothermal gas emissions, near-surface CO2 fluxes and concentrations are predominantly controlled by CO2 uptake by photosynthesis, production by root respiration, microbial decomposition of soil/subsoil organic matter, groundwater degassing, and exchange with the atmosphere. Available technologies for monitoring CO2 in the near-surface environment include the infrared gas analyzer, the accumulation chamber method, the eddy covariance method, hyperspectral imaging, and light detection and ranging. To meet the challenge of detecting potentially small-magnitude geothermal CO2 emissions within the natural background variability of CO2, we propose an approach that integrates available detection and monitoring techniques with statistical analysis and modeling strategies. The proposed monitoring plan initially focuses on rapid, economical, reliable measurements of CO2 subsurface concentrations and surface fluxes and statistical analysis of the collected data. Based on this analysis, are as with a high probability

  8. Multi-Channel Auto-Dilution System for Remote Continuous Monitoring of High Soil-CO2 Fluxes

    SciTech Connect

    Amonette, James E.; Barr, Jonathan L.

    2009-04-23

    Geological sequestration has the potential capacity and longevity to significantly decrease the amount of anthropogenic CO2 introduced into the atmosphere by combustion of fossil fuels such as coal. Effective sequestration, however, requires the ability to verify the integrity of the reservoir and ensure that potential leakage rates are kept to a minimum. Moreover, understanding the pathways by which CO2 migrates to the surface is critical to assessing the risks and developing remediation approaches. Field experiments, such as those conducted at the Zero Emissions Research and Technology (ZERT) project test site in Bozeman, Montana, require a flexible CO2 monitoring system that can accurately and continuously measure soil-surface CO2 fluxes for multiple sampling points at concentrations ranging from background levels to several tens of percent. To meet this need, PNNL is developing a multi-port battery-operated system capable of both spatial and temporal monitoring of CO2 at concentrations from ambient to at least 150,000 ppmv. This report describes the system components (sampling chambers, measurement and control system, and power supply) and the results of a field test at the ZERT site during the late summer and fall of 2008. While the system performed well overall during the field test, several improvements to the system are suggested for implementation in FY2009.

  9. The thermal performance of fuel matrix material in a CO2 atmosphere

    NASA Astrophysics Data System (ADS)

    Turner, J. D.; Schmidt, M. J. S.; Abram, T. J.

    2013-11-01

    The thermal oxidation performance of a semi-graphitic fuel matrix-material has been compared to two grades of nuclear graphite between 600 °C and 1200 °C in flowing CO2. Fuel matrix material is used to produce compacts or pebbles containing TRISO coated particle fuel for High Temperature Reactors (HTRs). The A3-27 fuel matrix-material grade was compared to NBG-18 and Gilsocarbon nuclear graphite grades. At 1200 °C temperatures A3-27 appears to be more reactive than NBG-18, but less so than Gilsocarbon. At 600 °C the oxidation rate of A3-27 is comparable to that of NBG-18, but both are significantly higher than that of Gilsocarbon. It is concluded that the comparable thermal oxidation behaviour of graphite and fuel-matrix material suggests that operating temperatures in a CO2 cooled reactor fuelled with TRISO coated particle fuel would not need to be reduced below those considered acceptable for the use of nuclear graphite.

  10. Influence of Fossil Fuel Emissions on CO2 Flux Estimation by Atmospheric Inversions

    NASA Astrophysics Data System (ADS)

    Saeki, T.; Patra, P. K.; van der Laan-Luijkx, I. T.; Peters, W.

    2015-12-01

    Top-down approaches (or atmospheric inversions) using atmospheric transport models with CO2 observations are an effective way to estimate carbon fluxes at global and regional scales. CO2 flux estimation by Bayesian inversions require a priori knowledge of terrestrial biosphere and oceanic fluxes and fossil fuel (FF) CO2 emissions. In most inversion frameworks, FF CO2 is assumed to be a known quantity because FF CO2 based on world statistics are thought to be more reliable than natural CO2 fluxes. However different databases of FF CO2 emissions may have different temporal and spatial variations especially at locations where statistics are not so accurate. In this study, we use 3 datasets of fossil fuel emissions in inversion estimations and evaluate the sensitivity of the optimized CO2 fluxes to FF emissions with two different inverse models, JAMSTEC's ACTM and CarbonTracker Europe (CTE). Interannually varying a priori FF CO2 emissions were based on 1) CDIAC database, 2) EDGARv4.2 database, and 3) IEA database, with some modifications. Biosphere and oceanic fluxes were optimized. Except for FF emissions, other conditions were kept the same in our inverse experiments. The three a priori FF emissions showed ~5% (~0.3GtC/yr) differences in their global total emissions in the early 2000's and the differences reached ~9% (~0.9 GtC/yr) in 2010. This resulted in 0.5-1 GtC/yr (2001-2011) and 0.3-0.6 GtC/yr (2007-2011) differences in the estimated global total emissions for the ACTM and CTE inversions, respectively. Regional differences in the FF emissions were relatively large in East Asia (~0.5 GtC/yr for ACTM and ~0.3 GtC/yr for CTE) and Europe (~0.3 GtC/yr for ACTM). These a priori flux differences caused differences in the estimated biosphere fluxes for ACTM in East Asia and Europe and also their neighboring regions such as West Asia, Boreal Eurasia, and North Africa. The main differences in the biosphere fluxes for CTE were found in Asia and the Americas.

  11. Simple dielectric mixing model in the monitoring of CO2 leakage from geological storage aquifer

    NASA Astrophysics Data System (ADS)

    Abidoye, L. K.; Bello, A. A.

    2017-01-01

    The principle of the dielectric mixing for multiphase systems in porous media has been employed to investigate CO2-water-porous media system and monitor the leakage of CO2, in analogy to scenarios that can be encountered in geological carbon sequestration. A dielectric mixing model was used to relate the relative permittivity for different subsurface materials connected with the geological carbon sequestration. The model was used to assess CO2 leakage and its upward migration, under the influences of the depth-dependent characteristics of the subsurface media as well as the fault-connected aquifers. The results showed that for the upward migration of CO2 in the subsurface, the change in the bulk relative permittivity (εb) of the CO2-water-porous media system clearly depicts the leakage and movement of CO2, especially at depth shallower than 800 m. At higher depth, with higher pressure and temperature, the relative permittivity of CO2 increases with pressure, while that of water decreases with temperature. These characteristics of water and supercritical CO2, combine to limit the change in the εb, at higher depth. Furthermore, it was noticed that if the pore water was not displaced by the migrating CO2, the presence of CO2 in the system increases the εb. But, with the displacement of pore water by the migrating CO2, it was shown how the εb profile decreases with time. Owing to its relative simplicity, composite dielectric behaviour of multiphase materials can be effectively deployed for monitoring and enhancement of control of CO2 movement in the geological carbon sequestration.

  12. Simple dielectric mixing model in the monitoring of CO2 leakage from geological storage aquifer

    NASA Astrophysics Data System (ADS)

    Abidoye, L. K.; Bello, A. A.

    2017-03-01

    The principle of the dielectric mixing for multiphase systems in porous media has been employed to investigate CO2-water-porous media system and monitor the leakage of CO2, in analogy to scenarios that can be encountered in geological carbon sequestration. A dielectric mixing model was used to relate the relative permittivity for different subsurface materials connected with the geological carbon sequestration. The model was used to assess CO2 leakage and its upward migration, under the influences of the depth-dependent characteristics of the subsurface media as well as the fault-connected aquifers. The results showed that for the upward migration of CO2 in the subsurface, the change in the bulk relative permittivity (εb) of the CO2-water-porous media system clearly depicts the leakage and movement of CO2, especially at depth shallower than 800 m. At higher depth, with higher pressure and temperature, the relative permittivity of CO2 increases with pressure, while that of water decreases with temperature. These characteristics of water and supercritical CO2, combine to limit the change in the εb, at higher depth. Furthermore, it was noted that if the pore water was not displaced by the migrating CO2, the presence of CO2 in the system increases the εb. But, with the displacement of pore water by the migrating CO2, it was shown how the εb profile decreases with time. Owing to its relative simplicity, composite dielectric behaviour of multiphase materials can be effectively deployed for monitoring and enhancement of control of CO2 movement in the geological carbon sequestration.

  13. Liquid Fuel From Microbial Communities: Electroalcoholgenesis: Bioelectrochemical Reduction of CO2 to Butanol

    SciTech Connect

    2010-07-01

    Electrofuels Project: MUSC is developing an engineered system to create liquid fuels from communities of interdependent microorganisms. MUSC is first pumping carbon dioxide (CO2) and renewable sources of electricity into a battery-like cell. A community of microorganisms uses the electricity to convert the CO2 into hydrogen. That hydrogen is then consumed by another community of microorganisms living in the same system. These new microorganisms convert the hydrogen into acetate, which in turn feed yet another community of microorganisms. This last community of microorganisms uses the acetate to produce a liquid biofuel called butanol. Similar interdependent microbial communities can be found in some natural environments, but they’ve never been coupled together in an engineered cell to produce liquid fuels. MUSC is working to triple the amount of butanol that can be produced in its system and to reduce the overall cost of the process.

  14. Continuous active-source seismic monitoring of CO2 injection in abrine aquifer

    SciTech Connect

    Daley, Thomas M.; Solbau, Ray D.; Ajo-Franklin, Jonathan B.; Benson, Sally M.

    2006-12-10

    Continuous crosswell seismic monitoring of a small-scale CO2injection was accomplished with the development of a noveltubing-deployed piezoelectric borehole source. This piezotube source wasdeployed on the CO2 injection tubing, near the top of the saline aquiferreservoir at 1657-m depth, and allowed acquisition of crosswellrecordings at 15-minute intervals during the multiday injection. Thechange in traveltime recorded at various depths in a nearby observationwell allowed hour-by-hour monitoring of the growing CO2 plume via theinduced seismic velocity change. Traveltime changes of 0.2 to 1.0 ms ( upto 8 percent ) were observed, with no change seen at control sensorsplaced above the reservoir. The traveltime measurements indicate that theCO2 plume reached the top of the reservoir sand before reaching theobservation well, where regular fluid sampling was occuring during theinjection, thus providing information about the in situ buoyancy ofCO2.

  15. A multiyear, global gridded fossil fuel CO2 emission data product: Evaluation and analysis of results

    NASA Astrophysics Data System (ADS)

    Asefi-Najafabady, S.; Rayner, P. J.; Gurney, K. R.; McRobert, A.; Song, Y.; Coltin, K.; Huang, J.; Elvidge, C.; Baugh, K.

    2014-09-01

    High-resolution, global quantification of fossil fuel CO2 emissions is emerging as a critical need in carbon cycle science and climate policy. We build upon a previously developed fossil fuel data assimilation system (FFDAS) for estimating global high-resolution fossil fuel CO2 emissions. We have improved the underlying observationally based data sources, expanded the approach through treatment of separate emitting sectors including a new pointwise database of global power plants, and extended the results to cover a 1997 to 2010 time series at a spatial resolution of 0.1°. Long-term trend analysis of the resulting global emissions shows subnational spatial structure in large active economies such as the United States, China, and India. These three countries, in particular, show different long-term trends and exploration of the trends in nighttime lights, and population reveal a decoupling of population and emissions at the subnational level. Analysis of shorter-term variations reveals the impact of the 2008-2009 global financial crisis with widespread negative emission anomalies across the U.S. and Europe. We have used a center of mass (CM) calculation as a compact metric to express the time evolution of spatial patterns in fossil fuel CO2 emissions. The global emission CM has moved toward the east and somewhat south between 1997 and 2010, driven by the increase in emissions in China and South Asia over this time period. Analysis at the level of individual countries reveals per capita CO2 emission migration in both Russia and India. The per capita emission CM holds potential as a way to succinctly analyze subnational shifts in carbon intensity over time. Uncertainties are generally lower than the previous version of FFDAS due mainly to an improved nightlight data set.

  16. FUEL ECONOMY AND CO2 EMISSIONS STANDARDS, MANUFACTURER PRICING STRATEGIES, AND FEEBATES

    SciTech Connect

    Liu, Changzheng; Greene, David L; Bunch, Dr David S.

    2012-01-01

    Corporate Average Fuel Economy (CAFE) standards and CO2 emissions standards for 2012 to 2016 have significantly increased the stringency of requirements for new light-duty vehicle fuel efficiency. This study investigates the role of technology adoption and pricing strategies in meeting new standards, as well as the impact of feebate policies. The analysis is carried out by means of a dynamic optimization model that simulates manufacturer decisions with the objective of maximizing social surplus while simultaneously considering consumer response and meeting CAFE and emissions standards. The results indicate that technology adoption plays the major role and that the provision of compliance flexibility and the availability of cost-effective advanced technologies help manufacturers reduce the need for pricing to induce changes in the mix of vehicles sold. Feebates, when implemented along with fuel economy and emissions standards, can bring additional fuel economy improvement and emissions reduction, but the benefit diminishes with the increasing stringency of the standards.

  17. Progress with the development of a CO 2 capturing solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Haines, M. R.; Heidug, W. K.; Li, K. J.; Moore, J. B.

    In April 2000 Siemens Westinghouse started work under a co-operation agreement with Shell International to develop and demonstrate a natural gas fired 0.25 MW solid oxide fuel cell (SOFC) modified to enable capture of carbon dioxide. The basic principles of this development and initial plans for the demonstration, which is due to start up at a Norwegian location in 2003, have been presented in environmental and fuel cell forums during 1999/2000. This paper reviews the latest technical progress with this development and discusses the large potential market for stationary power generation using SOFCs with CO 2 capturing capability.

  18. Inter-annual variability in fossil-fuel CO2 emissions due to temperature anomalies

    NASA Astrophysics Data System (ADS)

    Bréon, F.-M.; Boucher, O.; Brender, P.

    2017-07-01

    It is well known that short-term (i.e. interannual) variations in fossil-fuel CO2 emissions are closely related to the evolution of the national economies. Nevertheless, a fraction of the CO2 emissions are linked to domestic and business heating and cooling, which can be expected to be related to the meteorology, independently of the economy. Here, we analyse whether the signature of the inter-annual temperature anomalies is discernible in the time series of CO2 emissions at the country scale. Our analysis shows that, for many countries, there is a clear positive correlation between a heating-degree-person index and the component of the CO2 emissions that is not explained by the economy as quantified by the gross domestic product (GDP). Similarly, several countries show a positive correlation between a cooling-degree-person (CDP) index and CO2 emissions. The slope of the linear relationship for heating is on the order of 0.5-1 kg CO2 (degree-day-person)-1 but with significant country-to-country variations. A similar relationship for cooling shows even greater diversity. We further show that the inter-annual climate anomalies have a small but significant impact on the annual growth rate of CO2 emissions, both at the national and global scale. Such a meteorological effect was a significant contribution to the rather small and unexpected global emission growth rate in 2014 while its contribution to the near zero emission growth in 2015 was insignificant.

  19. Fire vs. fossil fuel: all CO2 emissions are not created equal

    NASA Astrophysics Data System (ADS)

    Landry, J.-S.; Matthews, H. D.

    2015-09-01

    Fire is arguably the most influential natural disturbance in terrestrial ecosystems, thereby playing a major role in carbon exchanges and affecting many climatic processes. Nevertheless, fire has not been the subject of dedicated studies in coupled climate-carbon models with interactive vegetation until very recently. Hence, previous studies resorted to results from simulations of fossil fuel emissions to estimate the effects of fire-induced CO2 emissions. While atmospheric CO2 molecules are all alike, fundamental differences in their origin suggest that the effects from fire emissions on the global carbon cycle and temperature are irreconcilable with the effects from fossil fuel emissions. The main purpose of this study is to illustrate the consequences from these fundamental differences between CO2 emissions from fossil fuels and non-deforestation fires (i.e., following which the natural vegetation can recover) using 1000-year simulations of a coupled climate-carbon model with interactive vegetation. We assessed emissions from both pulse and stable fire regime changes, considering both the gross (carbon released from combustion) and net (fire-caused change in land carbon, also accounting for vegetation decomposition and regrowth, as well as climate-carbon feedbacks) fire CO2 emissions. In all cases, we found substantial differences from equivalent amounts of emissions produced by fossil fuel combustion. These findings suggest that side-by-side comparisons of non-deforestation fire and fossil fuel CO2 emissions - implicitly implying that they have similar effects - should therefore be avoided, particularly when these comparisons involve gross fire emissions. Our results also support the notion that most net emissions occur relatively soon after fire regime shifts and then progressively approach zero, whereas gross emissions stabilize around a new value that is a poor indicator of the cumulative net emissions caused by the fire regime shift. Overall, our study

  20. Δ(14)CO2 from dark respiration in plants and its impact on the estimation of atmospheric fossil fuel CO2.

    PubMed

    Xiong, Xiaohu; Zhou, Weijian; Cheng, Peng; Wu, Shugang; Niu, Zhenchuan; Du, Hua; Lu, Xuefeng; Fu, Yunchong; Burr, George S

    2017-04-01

    Radiocarbon ((14)C) has been widely used for quantification of fossil fuel CO2 (CO2ff) in the atmosphere and for ecosystem source partitioning studies. The strength of the technique lies in the intrinsic differences between the (14)C signature of fossil fuels and other sources. In past studies, the (14)C content of CO2 derived from plants has been equated with the (14)C content of the atmosphere. Carbon isotopic fractionation mechanisms vary among plants however, and experimental study on fractionation associated with dark respiration is lacking. Here we present accelerator mass spectrometry (AMS) radiocarbon results of CO2 respired from 21 plants using a lab-incubation method and associated bulk organic matter. From the respired CO2 we determine Δ(14)Cres values, and from the bulk organic matter we determine Δ(14)Cbom values. A significant difference between Δ(14)Cres and Δ(14)Cbom (P < 0.01) was observed for all investigated plants, ranging from -42.3‰ to 10.1‰. The results show that Δ(14)Cres values are in agreement with mean atmospheric Δ(14)CO2 for several days leading up to the sampling date, but are significantly different from corresponding bulk organic Δ(14)C values. We find that although dark respiration is unlikely to significantly influence the estimation of CO2ff, an additional bias associated with the respiration rate during a plant's growth period should be considered when using Δ(14)C in plants to quantify atmospheric CO2ff. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The CO2 Vadose Project - Buffering capacity of a carbonate vadose zone on induced CO2 leakage. Part 1: monitoring in a natural pilot experimental field

    NASA Astrophysics Data System (ADS)

    Cohen, Grégory; Loisy, Corinne; Le Roux, Olivier; Garcia, Bruno; Rouchon, Virgile; Delaplace, Philippe; Cerepi, Adrian

    2013-04-01

    The Intergovernmental Panel on Climate Change Special Report on Carbon Capture and Storage identified various knowledge gaps that need to be resolved before the large-scale implementation of CO2 geological storage to become possible. One of them is to determine what would be the impact of a CO2 leakage from a geological storage on vadose zone and near surface environment. The CO2-Vadose project aims at i) understanding the behavior of CO2 in the near surface carbonate environment during an induced CO2 leakage, ii) assessing numerical simulations associated with CO2 release experiments and iii) developing integrated field methodologies to detect and quantify a potential CO2 leakage. A gas mixture of CO2 and tracers (He and Kr) was released in a cavity (9 m3, 7 m deep) located in an abandoned limestone quarry in Gironde (France). More than forty gas probes were set up (in the near surface and all around the cavity in limestone) for following CO2 concentrations before, during and after injection thanks to micro-GC and Li-Cor analyzers. The meteorological parameters were recorded at the site surface as well as around the injection room. Experimental observations of variations of electrical resistivity were also carried out in order to investigate the evolution of limestone geophysical property in response to possible leakages of geologically sequestered CO2. The dynamic evolution of electrical resistivity was measured thanks to time-lapse electrical resistivity tomography. Natural ground and limestone CO2 concentrations were monitored during a year before CO2 injection. Natural CO2 concentrations variations were observed in order to plot a natural baseline and so to determine the best period for the injection and to distinguish biogenic from injected CO2. These concentrations varied between about 400 ppm to more than 20,000 ppm, following cycles of about six weeks. Initial electrical resistivity tomography was also carried out just before the injection in order to have

  2. Advanced CO2 removal process control and monitor instrumentation development

    NASA Technical Reports Server (NTRS)

    Heppner, D. B.; Dalhausen, M. J.; Klimes, R.

    1982-01-01

    A progam to evaluate, design and demonstrate major advances in control and monitor instrumentation was undertaken. A carbon dioxide removal process, one whose maturity level makes it a prime candidate for early flight demonstration was investigated. The instrumentation design incorporates features which are compatible with anticipated flight requirements. Current electronics technology and projected advances are included. In addition, the program established commonality of components for all advanced life support subsystems. It was concluded from the studies and design activities conducted under this program that the next generation of instrumentation will be greatly smaller than the prior one. Not only physical size but weight, power and heat rejection requirements were reduced in the range of 80 to 85% from the former level of research and development instrumentation. Using a microprocessor based computer, a standard computer bus structure and nonvolatile memory, improved fabrication techniques and aerospace packaging this instrumentation will greatly enhance overall reliability and total system availability.

  3. Time-lapse crosswell seismic and VSP monitoring of injected CO2 in a brine aquifer

    NASA Astrophysics Data System (ADS)

    Daley, Thomas M.; Myer, Larry R.; Peterson, J. E.; Majer, E. L.; Hoversten, G. M.

    2008-06-01

    Seismic surveys successfully imaged a small scale CO2 injection (1,600 ton) conducted in a brine aquifer of the Frio Formation near Houston, Texas. These time-lapse borehole seismic surveys, crosswell and vertical seismic profile (VSP), were acquired to monitor the CO2 distribution using two boreholes (the new injection well and a pre-existing well used for monitoring) which are 30 m apart at a depth of 1,500 m. The crosswell survey provided a high-resolution image of the CO2 distribution between the wells via tomographic imaging of the P-wave velocity decrease (up to 500 m/s). The simultaneously acquired S-wave tomography showed little change in S-wave velocity, as expected for fluid substitution. A rock physics model was used to estimate CO2 saturations of 10 20% from the P-wave velocity change. The VSP survey resolved a large (˜70%) change in reflection amplitude for the Frio horizon. This CO2 induced reflection amplitude change allowed estimation of the CO2 extent beyond the monitor well and on three azimuths. The VSP result is compared with numerical modeling of CO2 saturations and is seismically modeled using the velocity change estimated in the crosswell survey.

  4. 40 CFR 600.207-12 - Calculation and use of vehicle-specific 5-cycle-based fuel economy and CO2 emission values for...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-specific 5-cycle-based fuel economy and CO2 emission values for vehicle configurations. 600.207-12 Section... ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Procedures for Calculating Fuel Economy and... fuel economy and CO2 emission values for vehicle configurations. (a) Fuel economy and CO2...

  5. Geophysical Monitoring at the Aquistore CO2 Storage Site, Saskatchewan, Canada (Invited)

    NASA Astrophysics Data System (ADS)

    White, D. J.

    2013-12-01

    The Aquistore Project, located near Estevan, Saskatchewan, is designed to demonstrate CO2 storage in a deep saline aquifer. CO2 captured from the nearby Boundary Dam coal-fired power plant will be injected into a brine-filled sandstone formation at ~3300 m depth, starting in November, 2013. A key element of the Aquistore research program is the further development of geophysical methods to monitor the security and subsurface distribution of the injected CO2. Toward this end, a spectrum of geophysical techniques are being tested at the Aquistore site. Various time-lapse seismic methods, including 3D surface and vertical seismic profiles (VSP) as well as crosswell seismic tomography, are designed to provide monitoring of the CO2 plume. Novel components of the seismic monitoring include use of a sparse permanent array and borehole recording using a fiber optic distributed acoustic sensor (DAS) system. Gravity and electromagnetic methods are providing complementary monitoring. Pre-injection baseline surveys have been acquired for each of these methods. In addition, continuous pre-injection monitoring has been ongoing since the summer of 2012 to establish background surface deformation patterns and local seismicity prior to the start of CO2 injection. A network of GPS stations, surface tiltmeters and InSAR reflectors has been deployed to monitor injection-related surface deformation. Passive seismic monitoring is being conducted using two orthogonal linear arrays of surface geophones.

  6. Geophysical Monitoring at the Aquistore CO2 Storage Site, Saskatchewan, Canada (Invited)

    NASA Astrophysics Data System (ADS)

    Wang, L.; Huang, Z.; Xu, M.; Mi, N.; Yu, D.; Li, H.

    2011-12-01

    The Aquistore Project, located near Estevan, Saskatchewan, is designed to demonstrate CO2 storage in a deep saline aquifer. CO2 captured from the nearby Boundary Dam coal-fired power plant will be injected into a brine-filled sandstone formation at ~3300 m depth, starting in November, 2013. A key element of the Aquistore research program is the further development of geophysical methods to monitor the security and subsurface distribution of the injected CO2. Toward this end, a spectrum of geophysical techniques are being tested at the Aquistore site. Various time-lapse seismic methods, including 3D surface and vertical seismic profiles (VSP) as well as crosswell seismic tomography, are designed to provide monitoring of the CO2 plume. Novel components of the seismic monitoring include use of a sparse permanent array and borehole recording using a fiber optic distributed acoustic sensor (DAS) system. Gravity and electromagnetic methods are providing complementary monitoring. Pre-injection baseline surveys have been acquired for each of these methods. In addition, continuous pre-injection monitoring has been ongoing since the summer of 2012 to establish background surface deformation patterns and local seismicity prior to the start of CO2 injection. A network of GPS stations, surface tiltmeters and InSAR reflectors has been deployed to monitor injection-related surface deformation. Passive seismic monitoring is being conducted using two orthogonal linear arrays of surface geophones.

  7. Geophysical Techniques for Monitoring CO2 Movement During Sequestration

    SciTech Connect

    Erika Gasperikova; G. Michael Hoversten

    2005-11-15

    The relative merits of the seismic, gravity, and electromagnetic (EM) geophysical techniques are examined as monitoring tools for geologic sequestration of carbon dioxide (CO{sub 2}). This work does not represent an exhaustive study, but rather demonstrates the capabilities of a number of geophysical techniques for two synthetic modeling scenarios. The first scenario represents combined CO{sub 2} enhanced oil recovery (EOR) and sequestration in a producing oil field, the Schrader Bluff field on the north slope of Alaska, USA. EOR/sequestration projects in general and Schrader Bluff in particular represent relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine, and CO{sub 2}). This model represents the most difficult end member of a complex spectrum of possible sequestration scenarios. The time-lapse performance of seismic, gravity, and EM techniques are considered for the Schrader Bluff model. The second scenario is a gas field that in general resembles conditions of Rio Vista reservoir in the Sacramento Basin of California. Surface gravity, and seismic measurements are considered for this model.

  8. CO2 Injection Test in a Shallow Aquifer: Monitoring via Use of Different Technologies

    NASA Astrophysics Data System (ADS)

    Lamert, H.; Dietrich, P.; Werban, U.; Steinbrueckner, D.; Schulz, A.; Peter, A.; Grossmann, J.; Beyer, M.

    2011-12-01

    A promising tool for the reduction of CO2 emissions into the atmosphere is CCS (Carbon Capture and Storage). However, the availability of efficient methods for the detection and monitoring of potential CO2 degassing is a prerequisite for CO2 sequestration as well as for the public acceptance of this controversially discussed technology in general. Before implementing the CCS technology, a sound risk assessment and monitoring strategy is absolutely necessary. The aim of the project is to emulate a CO2 leakage scenario by injecting gaseous CO2 into a shallow aquifer. This field study was performed at a former military air field over a period of ten days in March and April 2011. One of the main objectives is to develop and test different monitoring methods applied to controlled CO2 intrusion in a shallow groundwater system. Thirty-four installed monitoring wells, predominantly oriented to the main groundwater flow direction, allow the sampling of groundwater during the injection test. Gaseous CO2 injection into the groundwater causes increasing electric resistivity. The subsequent dissolution and dissociation processes lead, in general, to decreasing pH and increasing electric conductivity. Installed wells were equipped with electrodes at different depths to detect changes in electric resistivity in the underground. Initial results show significant breakthrough curves of the electric resistivity signal affected by the injected CO2. Groundwater samples were taken before, during and after the injection test to validate these data. Field parameters (pH, electric conductivity) and stable isotope data were compared with the measured geoelectric data. Thus, the electric resistivity changes can be clearly related to the geochemically changed groundwater caused by the injected CO2.

  9. Global, Regional, and National Fossil-Fuel CO2 Emissions, 1751 - 2009

    DOE Data Explorer

    Boden, Thomas A. [CDIAC, Oak Ridge National Laboratory; Andres, Robert J. [Oak Ridge National Laboratory; Marland, G. [Research Institute for Environment, Energy and Economics, Appalachian State University

    2012-01-01

    Publications containing historical energy statistics make it possible to estimate fossil fuel CO2 emissions back to 1751. Etemad et al. (1991) published a summary compilation that tabulates coal, brown coal, peat, and crude oil production by nation and year. Footnotes in the Etemad et al.(1991) publication extend the energy statistics time series back to 1751. Summary compilations of fossil fuel trade were published by Mitchell (1983, 1992, 1993, 1995). Mitchell's work tabulates solid and liquid fuel imports and exports by nation and year. These pre-1950 production and trade data were digitized and CO2 emission calculations were made following the procedures discussed in Marland and Rotty (1984) and Boden et al. (1995). Further details on the contents and processing of the historical energy statistics are provided in Andres et al. (1999). The 1950 to present CO2 emission estimates are derived primarily from energy statistics published by the United Nations (2012), using the methods of Marland and Rotty (1984). The energy statistics were compiled primarily from annual questionnaires distributed by the U.N. Statistical Office and supplemented by official national statistical publications. As stated in the introduction of the Statistical Yearbook, "in a few cases, official sources are supplemented by other sources and estimates, where these have been subjected to professional scrutiny and debate and are consistent with other independent sources." Data from the U.S. Department of Interior's Geological Survey (USGS 2011) were used to estimate CO2 emitted during cement production. Values for emissions from gas flaring were derived primarily from U.N. data but were supplemented with data from the U.S. Department of Energy's Energy Information Administration (1994), Rotty (1974), and data provided by G. Marland. Greater details about these methods are provided in Marland and Rotty (1984), Boden et al. (1995), and Andres et al. (1999).

  10. Global, Regional, and National Fossil-Fuel CO2 Emissions, 1751 - 2006 (published 2009)

    DOE Data Explorer

    Boden, Thomas A. [CDIAC, Oak Ridge National Laboratory; Marland, G. [CDIAC, Oak Ridge National Laboratory; Andres, Robert J. [CDIAC, Oak Ridge National Laboratory

    2009-01-01

    Publications containing historical energy statistics make it possible to estimate fossil fuel CO2 emissions back to 1751. Etemad et al. (1991) published a summary compilation that tabulates coal, brown coal, peat, and crude oil production by nation and year. Footnotes in the Etemad et al.(1991) publication extend the energy statistics time series back to 1751. Summary compilations of fossil fuel trade were published by Mitchell (1983, 1992, 1993, 1995). Mitchell's work tabulates solid and liquid fuel imports and exports by nation and year. These pre-1950 production and trade data were digitized and CO2 emission calculations were made following the procedures discussed in Marland and Rotty (1984) and Boden et al. (1995). Further details on the contents and processing of the historical energy statistics are provided in Andres et al. (1999). The 1950 to present CO2 emission estimates are derived primarily from energy statistics published by the United Nations (2008), using the methods of Marland and Rotty (1984). The energy statistics were compiled primarily from annual questionnaires distributed by the U.N. Statistical Office and supplemented by official national statistical publications. As stated in the introduction of the Statistical Yearbook, "in a few cases, official sources are supplemented by other sources and estimates, where these have been subjected to professional scrutiny and debate and are consistent with other independent sources." Data from the U.S. Department of Interior's Geological Survey (USGS 2008) were used to estimate CO2 emitted during cement production. Values for emissions from gas flaring were derived primarily from U.N. data but were supplemented with data from the U.S. Department of Energy's Energy Information Administration (1994), Rotty (1974), and data provided by G. Marland. Greater details about these methods are provided in Marland and Rotty (1984), Boden et al. (1995), and Andres et al. (1999).

  11. GLOBAL, REGIONAL, AND NATIONAL FOSSIL-FUEL CO2 EMISSIONS, 1751 - 2007 (Version 2010)

    DOE Data Explorer

    Boden, Thomas A. [CDIAC, Oak Ridge National Laboratory; Marland, G. [CDIAC, Oak Ridge National Laboratory; Andres, Robert J. [CDIAC, Oak Ridge National Laboratory

    2010-01-01

    Publications containing historical energy statistics make it possible to estimate fossil fuel CO2 emissions back to 1751. Etemad et al. (1991) published a summary compilation that tabulates coal, brown coal, peat, and crude oil production by nation and year. Footnotes in the Etemad et al.(1991) publication extend the energy statistics time series back to 1751. Summary compilations of fossil fuel trade were published by Mitchell (1983, 1992, 1993, 1995). Mitchell's work tabulates solid and liquid fuel imports and exports by nation and year. These pre-1950 production and trade data were digitized and CO2 emission calculations were made following the procedures discussed in Marland and Rotty (1984) and Boden et al. (1995). Further details on the contents and processing of the historical energy statistics are provided in Andres et al. (1999). The 1950 to present CO2 emission estimates are derived primarily from energy statistics published by the United Nations (2009), using the methods of Marland and Rotty (1984). The energy statistics were compiled primarily from annual questionnaires distributed by the U.N. Statistical Office and supplemented by official national statistical publications. As stated in the introduction of the Statistical Yearbook, "in a few cases, official sources are supplemented by other sources and estimates, where these have been subjected to professional scrutiny and debate and are consistent with other independent sources." Data from the U.S. Department of Interior's Geological Survey (USGS 2009) were used to estimate CO2 emitted during cement production. Values for emissions from gas flaring were derived primarily from U.N. data but were supplemented with data from the U.S. Department of Energy's Energy Information Administration (1994), Rotty (1974), and data provided by G. Marland. Greater details about these methods are provided in Marland and Rotty (1984), Boden et al. (1995), and Andres et al. (1999).

  12. Global, Regional, and National Fossil-Fuel CO2 Emissions, 1751 - 2008 (Version 2011)

    DOE Data Explorer

    Boden, Thomas A. [CDIAC, Oak Ridge National Laboratory; Marland, G. [CDIAC, Oak Ridge National Laboratory; Andres, Robert J. [CDIAC, Oak Ridge National Laboratory

    2011-01-01

    Publications containing historical energy statistics make it possible to estimate fossil fuel CO2 emissions back to 1751. Etemad et al. (1991) published a summary compilation that tabulates coal, brown coal, peat, and crude oil production by nation and year. Footnotes in the Etemad et al.(1991) publication extend the energy statistics time series back to 1751. Summary compilations of fossil fuel trade were published by Mitchell (1983, 1992, 1993, 1995). Mitchell's work tabulates solid and liquid fuel imports and exports by nation and year. These pre-1950 production and trade data were digitized and CO2 emission calculations were made following the procedures discussed in Marland and Rotty (1984) and Boden et al. (1995). Further details on the contents and processing of the historical energy statistics are provided in Andres et al. (1999). The 1950 to present CO2 emission estimates are derived primarily from energy statistics published by the United Nations (2010), using the methods of Marland and Rotty (1984). The energy statistics were compiled primarily from annual questionnaires distributed by the U.N. Statistical Office and supplemented by official national statistical publications. As stated in the introduction of the Statistical Yearbook, "in a few cases, official sources are supplemented by other sources and estimates, where these have been subjected to professional scrutiny and debate and are consistent with other independent sources." Data from the U.S. Department of Interior's Geological Survey (USGS 2010) were used to estimate CO2 emitted during cement production. Values for emissions from gas flaring were derived primarily from U.N. data but were supplemented with data from the U.S. Department of Energy's Energy Information Administration (1994), Rotty (1974), and data provided by G. Marland. Greater details about these methods are provided in Marland and Rotty (1984), Boden et al. (1995), and Andres et al. (1999).

  13. Global, Regional, and National Fossil-Fuel CO2 Emissions, 1751 - 2010

    DOE Data Explorer

    Boden, Thomas A. [CDIAC, Oak Ridge National Laboratory; Andres, Robert J. [CDIAC, Oak Ridge National Laboratory; Marland, G.

    2013-01-01

    Publications containing historical energy statistics make it possible to estimate fossil fuel CO2 emissions back to 1751. Etemad et al. (1991) published a summary compilation that tabulates coal, brown coal, peat, and crude oil production by nation and year. Footnotes in the Etemad et al.(1991) publication extend the energy statistics time series back to 1751. Summary compilations of fossil fuel trade were published by Mitchell (1983, 1992, 1993, 1995). Mitchell's work tabulates solid and liquid fuel imports and exports by nation and year. These pre-1950 production and trade data were digitized and CO2 emission calculations were made following the procedures discussed in Marland and Rotty (1984) and Boden et al. (1995). Further details on the contents and processing of the historical energy statistics are provided in Andres et al. (1999). The 1950 to present CO2 emission estimates are derived primarily from energy statistics published by the United Nations (2013), using the methods of Marland and Rotty (1984). The energy statistics were compiled primarily from annual questionnaires distributed by the U.N. Statistical Office and supplemented by official national statistical publications. As stated in the introduction of the Statistical Yearbook, "in a few cases, official sources are supplemented by other sources and estimates, where these have been subjected to professional scrutiny and debate and are consistent with other independent sources." Data from the U.S. Department of Interior's Geological Survey (USGS 2012) were used to estimate CO2 emitted during cement production. Values for emissions from gas flaring were derived primarily from U.N. data but were supplemented with data from the U.S. Department of Energy's Energy Information Administration (1994), Rotty (1974), and data provided by G. Marland. Greater details about these methods are provided in Marland and Rotty (1984), Boden et al. (1995), and Andres et al. (1999).

  14. Using the Bongwana natural CO2 release to understand leakage processes and develop monitoring

    NASA Astrophysics Data System (ADS)

    Jones, David; Johnson, Gareth; Hicks, Nigel; Bond, Clare; Gilfillan, Stuart; Kremer, Yannick; Lister, Bob; Nkwane, Mzikayise; Maupa, Thulani; Munyangane, Portia; Robey, Kate; Saunders, Ian; Shipton, Zoe; Pearce, Jonathan; Haszeldine, Stuart

    2016-04-01

    Natural CO2 leakage along the Bongwana Fault in South Africa is being studied to help understand processes of CO2 leakage and develop monitoring protocols. The Bongwana Fault crops out over approximately 80 km in KwaZulu-Natal province, South Africa. In outcrop the fault is expressed as a broad fracture corridor in Dwyka Tillite, with fractures oriented approximately N-S. Natural emissions of CO2 occur at various points along the fault, manifest as travertine cones and terraces, bubbling in the rivers and as gas fluxes through soil. Exposed rock outcrop shows evidence for Fe-staining around fractures and is locally extensively kaolinitised. The gas has also been released through a shallow water well, and was exploited commercially in the past. Preliminary studies have been carried out to better document the surface emissions using near surface gas monitoring, understand the origin of the gas through major gas composition and stable and noble gas isotopes and improve understanding of the structural controls on gas leakage through mapping. In addition the impact of the leaking CO2 on local water sources (surface and ground) is being investigated, along with the seismic activity of the fault. The investigation will help to build technical capacity in South Africa and to develop monitoring techniques and plans for a future CO2 storage pilot there. Early results suggest that CO2 leakage is confined to a relatively small number of spatially-restricted locations along the weakly seismically active fault. Fracture permeability appears to be the main method by which the CO2 migrates to the surface. The bulk of the CO2 is of deep origin with a minor contribution from near surface biogenic processes as determined by major gas composition. Water chemistry, including pH, DO and TDS is notably different between CO2-rich and CO2-poor sites. Soil gas content and flux effectively delineates the fault trace in active leakage sites. The fault provides an effective testing ground for

  15. Gravity monitoring of CO2 movement during sequestration: Model studies

    SciTech Connect

    Gasperikova, E.; Hoversten, G.M.

    2008-07-15

    We examine the relative merits of gravity measurements as a monitoring tool for geological CO{sub 2} sequestration in three different modeling scenarios. The first is a combined CO{sub 2} enhanced oil recovery (EOR) and sequestration in a producing oil field, the second is sequestration in a brine formation, and the third is for a coalbed methane formation. EOR/sequestration petroleum reservoirs have relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine, and CO{sub 2}), whereas brine formations usually have much thicker injection intervals and only two components (brine and CO{sub 2}). Coal formations undergoing methane extraction tend to be thin (3-10 m), but shallow compared to either EOR or brine formations. The injection of CO{sub 2} into the oil reservoir produced a bulk density decrease in the reservoir. The spatial pattern of the change in the vertical component of gravity (G{sub z}) is directly correlated with the net change in reservoir density. Furthermore, time-lapse changes in the borehole G{sub z} clearly identified the vertical section of the reservoir where fluid saturations are changing. The CO{sub 2}-brine front, on the order of 1 km within a 20 m thick brine formation at 1900 m depth, with 30% CO{sub 2} and 70% brine saturations, respectively, produced a -10 Gal surface gravity anomaly. Such anomaly would be detectable in the field. The amount of CO{sub 2} in a coalbed methane test scenario did not produce a large enough surface gravity response; however, we would expect that for an industrial size injection, the surface gravity response would be measurable. Gravity inversions in all three scenarios illustrated that the general position of density changes caused by CO{sub 2} can be recovered, but not the absolute value of the change. Analysis of the spatial resolution and detectability limits shows that gravity measurements could, under certain circumstances, be used as a lower-cost alternative to seismic

  16. Monitoring Ocean CO2 Fluxes from Space: GOSAT and OCO-2

    NASA Technical Reports Server (NTRS)

    Crisp, David

    2012-01-01

    The ocean is a major component of the global carbon cycle, emitting over 330 billion tons of carbon dioxide (CO2) into the atmosphere each year, or about 10 times that emitted fossil fuel combustion and all other human activities [1, 2]. The ocean reabsorbs a comparable amount of CO2 each year, along with 25% of the CO2 emitted by these human activities. The nature and geographic distribution of the processes controlling these ocean CO2 fluxes are still poorly constrained by observations. A better understanding of these processes is essential to predict how this important CO2 sink may evolve as the climate changes.While in situ measurements of ocean CO2 fluxes can be very precise, the sampling density is far too sparse to quantify ocean CO2 sources and sinks over much of the globe. One way to improve the spatial resolution, coverage, and sampling frequency is to make observations of the column averaged CO2 dry air mole fraction, XCO2, from space [4, 5, 6]. Such measurements could provide global coverage at high resolution (< 100 km) on monthly time scales. High precision (< 1 part per million, ppm) is essential to resolve the small, near-surface CO2 variations associated with ocean fluxes and to better constrain the CO2 transport over the ocean. The Japanese Greenhouse gases Observing Satellite (GOSAT) and the NASA Orbiting Carbon Observatory (OCO) were first two space based sensors designed specifically for this task. GOSAT was successfully launched on January 23, 2009, and has been returning measurements of XCO2 since April 2009. The OCO mission was lost in February 2009, when its launch vehicle malfunctioned and failed to reach orbit. In early 2010, NASA authorized a re-flight of OCO, called OCO-2, which is currently under development.

  17. Inhibited proton transfer enhances Au-catalyzed CO2-to-fuels selectivity

    PubMed Central

    Wuttig, Anna; Yaguchi, Momo; Motobayashi, Kenta; Osawa, Masatoshi; Surendranath, Yogesh

    2016-01-01

    CO2 reduction in aqueous electrolytes suffers efficiency losses because of the simultaneous reduction of water to H2. We combine in situ surface-enhanced IR absorption spectroscopy (SEIRAS) and electrochemical kinetic studies to probe the mechanistic basis for kinetic bifurcation between H2 and CO production on polycrystalline Au electrodes. Under the conditions of CO2 reduction catalysis, electrogenerated CO species are irreversibly bound to Au in a bridging mode at a surface coverage of ∼0.2 and act as kinetically inert spectators. Electrokinetic data are consistent with a mechanism of CO production involving rate-limiting, single-electron transfer to CO2 with concomitant adsorption to surface active sites followed by rapid one-electron, two-proton transfer and CO liberation from the surface. In contrast, the data suggest an H2 evolution mechanism involving rate-limiting, single-electron transfer coupled with proton transfer from bicarbonate, hydronium, and/or carbonic acid to form adsorbed H species followed by rapid one-electron, one-proton, or H recombination reactions. The disparate proton coupling requirements for CO and H2 production establish a mechanistic basis for reaction selectivity in electrocatalytic fuel formation, and the high population of spectator CO species highlights the complex heterogeneity of electrode surfaces under conditions of fuel-forming electrocatalysis. PMID:27450088

  18. Atmospheric CO2 Concentrations--The Canadian Background Air Pollution Monitoring Network (1993)

    DOE Data Explorer

    Trivett, N. B. A.; Hudec, V. C.; Wong, C. S.

    1993-01-01

    Flask air samples collected at roughly weekly intervals at three Canadian sites [Alert, Northwest Territories (July 1975 through July 1992); Sable Island, Nova Scotia (March 1975 through July 1992); and Cape St. James, British Columbia (May 1979 through July 1992)] were analyzed for CO2 concentration with the measurements directly traceable to the WMO primary CO2 standards. Each record includes the date, atmospheric CO2 concentration, and flask classification code. They provide an accurate record of CO2 concentration levels in Canada during the past two decades. Because these data are directly traceable to WMO standards, this record may be compared with records from other Background Air Pollution Monitoring Network (BAPMoN) stations. The data are in three files (one for each of the monitoring stations) ranging in size from 9.4 to 20.1 kB.

  19. Subsurface Monitoring of CO2 Sequestration - A Review and Look Forward

    NASA Astrophysics Data System (ADS)

    Daley, T. M.

    2012-12-01

    The injection of CO2 into subsurface formations is at least 50 years old with large-scale utilization of CO2 for enhanced oil recovery (CO2-EOR) beginning in the 1970s. Early monitoring efforts had limited measurements in available boreholes. With growing interest in CO2 sequestration beginning in the 1990's, along with growth in geophysical reservoir monitoring, small to mid-size sequestration monitoring projects began to appear. The overall goals of a subsurface monitoring plan are to provide measurement of CO2 induced changes in subsurface properties at a range of spatial and temporal scales. The range of spatial scales allows tracking of the location and saturation of the plume with varying detail, while finer temporal sampling (up to continuous) allows better understanding of dynamic processes (e.g. multi-phase flow) and constraining of reservoir models. Early monitoring of small scale pilots associated with CO2-EOR (e.g., the McElroy field and the Lost Hills field), developed many of the methodologies including tomographic imaging and multi-physics measurements. Large (reservoir) scale sequestration monitoring began with the Sleipner and Weyburn projects. Typically, large scale monitoring, such as 4D surface seismic, has limited temporal sampling due to costs. Smaller scale pilots can allow more frequent measurements as either individual time-lapse 'snapshots' or as continuous monitoring. Pilot monitoring examples include the Frio, Nagaoka and Otway pilots using repeated well logging, crosswell imaging, vertical seismic profiles and CASSM (continuous active-source seismic monitoring). For saline reservoir sequestration projects, there is typically integration of characterization and monitoring, since the sites are not pre-characterized resource developments (oil or gas), which reinforces the need for multi-scale measurements. As we move beyond pilot sites, we need to quantify CO2 plume and reservoir properties (e.g. pressure) over large scales, while still

  20. A comparison of near surface CO2 monitoring methods and their applicability in the CCS context

    NASA Astrophysics Data System (ADS)

    Möller, Ingo; Schlömer, Stefan

    2014-05-01

    The detection, characterization and quantification of different gas species in the vicinity of the soil-atmosphere interface is considered as one key element of near surface monitoring related to CO2 storage operations. From a broad range of available techniques (see e.g. Korre et al. 2011 and Rütters et al. 2013), three different methods have initially been selected in order to compare their applicability in the CCS context: - The eddy covariance method which can compute CO2 fluxes within the atmospheric boundary layer, - CO2 flux measurements between soil and atmosphere by means of accumulation chambers, - Permanent CO2 concentration measurements in the vadose zone of the soil column. Additionally, basic atmospheric CO2 concentration measurements were also included in this comparison since they might have a potential as monitoring alternative on a low-cost basis. Results and lessons learned from practical field experiments were elaborated to point out advantages and disadvantages of the individual methods as well as their integration into an overall monitoring concept of CO2 storage sites. Field work has been carried out in different locations of Northern Germany, amongst others in the Altmark region, a formerly proposed CO2 injection site for enhanced gas recovery (Schlömer et al. 2014). This study benefits from interim results of the MONACO project (Monitoring approach for geological CO2 storage sites using an hierarchic observation concept) which is funded by the German Federal Ministry of Education and Research (BMBF, grant 03G0817A). References: Korre, A., Imrie, C.E., May, F., Beaubien, S.E., Vandermeijer, V., Persoglia, S., Golmen, L., Fabriol, H., Dixon, T., 2011. Quantification techniques for potential CO2 leakage from geological storage sites. Energy Proc. 4, pp. 3413-3420. Rütters, H., Möller, I., May, F., Flornes, K., Hladik, V., Arvanitis, A., Gülec, N.,Bakiler, C., Dudu, A., Kucharic, L., Juhojuntti, N., Shogenova, A., Georgiev, G., 2013. State

  1. Significant long-term increase of fossil fuel CO2 uptake from reduced marine calcification

    NASA Astrophysics Data System (ADS)

    Ridgwell, A.; Zondervan, I.; Hargreaves, J. C.; Bijma, J.; Lenton, T. M.

    2006-11-01

    Analysis of available plankton manipulation experiments demonstrates a previously unrecognized wide range of sensitivities of biogenic calcification to simulated anthropogenic acidification of the ocean, with the "lab rat" of planktic calcifiers, Emiliania huxleyi not representative of calcification generally. We assess the implications of the experimental uncertainty in plankton calcification response by creating an ensemble of realizations of an Earth system model that encapsulates a comparable range of uncertainty in calcification response. We predict a substantial future reduction in marine carbonate production, with ocean CO2 sequestration across the model ensemble enhanced by between 62 and 199 PgC by the year 3000, equivalent to a reduction in the atmospheric fossil fuel CO2 burden at that time of up to 13%. Concurrent changes in ocean circulation and surface temperatures contribute about one third to the overall importance of reduced plankton calcification.

  2. Direct Experiments on the Ocean Disposal of Fossil Fuel CO2

    SciTech Connect

    Barry, James, P.

    2010-05-26

    Funding from DoE grant # FG0204-ER63721, Direct Experiments on the Ocean Disposal of Fossil Fuel CO2, supposed several postdoctoral fellows and research activities at MBARI related to ocean CO2 disposal and the biological consequences of high ocean CO2 levels on marine organisms. Postdocs supported on the project included Brad Seibel, now an associate professor at the University of Rhode Island, Jeff Drazen, now an associate professor at the University of Hawaii, and Eric Pane, who continues as a research associate at MBARI. Thus, the project contributed significantly to the professional development of young scientists. In addition, we made significant progress in several research areas. We continued several deep-sea CO2 release experiments using support from DoE and MBARI, along with several collaborators. These CO2 release studies had the goal of broadening our understanding of the effects of high ocean CO2 levels on deep sea animals in the vicinity of potential release sites for direct deep-ocean carbon dioxide sequestration. Using MBARI ships and ROVs, we performed these experiments at depths of 3000 to 3600 m, where liquid CO2 is heavier than seawater. CO2 was released into small pools (sections of PVC pipe) on the seabed, where it dissolved and drifted downstream, bathing any caged animals and sediments in a CO2-rich, low-pH plume. We assessed the survival of organisms nearby. Several publications arose from these studies (Barry et al. 2004, 2005; Carman et al. 2004; Thistle et al. 2005, 2006, 2007; Fleeger et al. 2006, 2010; Barry and Drazen 2007; Bernhard et al. 2009; Sedlacek et al. 2009; Ricketts et al. in press; Barry et al, in revision) concerning the sensitivity of animals to low pH waters. Using funds from DoE and MBARI, we designed and fabricated a hyperbaric trap-respirometer to study metabolic rates of deep-sea fishes under high CO2 conditions (Drazen et al, 2005), as well as a gas-control aquarium system to support laboratory studies of the

  3. Numerical modeling of time-lapse monitoring of CO2 sequestration in a layered basalt reservoir

    USGS Publications Warehouse

    Khatiwada, M.; Van Wijk, K.; Clement, W.P.; Haney, M.

    2008-01-01

    As part of preparations in plans by The Big Sky Carbon Sequestration Partnership (BSCSP) to inject CO2 in layered basalt, we numerically investigate seismic methods as a noninvasive monitoring technique. Basalt seems to have geochemical advantages as a reservoir for CO2 storage (CO2 mineralizes quite rapidly while exposed to basalt), but poses a considerable challenge in term of seismic monitoring: strong scattering from the layering of the basalt complicates surface seismic imaging. We perform numerical tests using the Spectral Element Method (SEM) to identify possibilities and limitations of seismic monitoring of CO2 sequestration in a basalt reservoir. While surface seismic is unlikely to detect small physical changes in the reservoir due to the injection of CO2, the results from Vertical Seismic Profiling (VSP) simulations are encouraging. As a perturbation, we make a 5%; change in wave velocity, which produces significant changes in VSP images of pre-injection and post-injection conditions. Finally, we perform an analysis using Coda Wave Interferometry (CWI), to quantify these changes in the reservoir properties due to CO2 injection.

  4. Geochemical Monitoring for Potential Environmental Impacts of Geologic Sequestration of CO2

    NASA Astrophysics Data System (ADS)

    Thomas, B.; Kharaka, Y. K.; Cole, D. R.; Thordsen, J. J.; Conaway, C. H.; Gans, K. D.

    2013-12-01

    Geologically sequestered CO2 is buoyant, has a low viscosity and, when dissolved in brine, becomes reactive to minerals, cements and well pipes. These properties of CO2 may cause it to leak upward from the major storage reservoirs, possibly contaminating underground sources of drinking water. We have participated in several multi-laboratory field experiments to investigate the changes in chemical and isotopic parameters and added tracers that are applicable to the monitoring of the flow of injected CO2 in reservoirs and leakage into potable shallow groundwater. Geochemical results from the Frio Brine I and II pilot tests located near Dayton, Texas and from the SECARB Phase III tests at Cranfield oil field, Mississippi, proved powerful tools in: 1- Tracking the successful injection and flow of CO2 into the injection sandstones; 2- showing major changes in the chemical (pH, alkalinity, and major divalent cations) and isotopic (δ13C values of CO2, and δ18O values of CO2, and brine) compositions of formation water; 3-. showing mobilization of metals, including Fe Mn and Pb, and organic compounds , including DOC, BTEX, PAHs, and phenols following CO2 injection; and 4- showing that some of the CO2 injected into the Frio 'C' sandstone was detected in the overlying 'B' sandstone that is separated by 15 m of shale and muddy siltstone. Rapid, significant and systematic changes were also observed in the isotopic and chemical compositions of shallow groundwater at the ZERT site located in Bozeman, MT, in response to four yearly controlled injections of CO2 gas through a slotted pipe placed horizontally at a depth of ~2 m below ground level. The observed changes, included the lowering of groundwater pH from ~7.0 to values as low as 5.6, increases in the alkalinity from about 400 mg/L as HCO3 to values of up to 1330 mg/L, increases in the electrical conductance from ~600 μS/cm to up to 1800 μS/cm, as well as increases in the concentrations of cations and metals following CO2

  5. A field and laboratory method for monitoring the concentration and isotopic composition of soil CO2.

    PubMed

    Breecker, Dan; Sharp, Zachary D

    2008-01-01

    The stable isotope composition of nmol size gas samples can be determined accurately and precisely using continuous flow isotope ratio mass spectrometry (IRMS). We have developed a technique that exploits this capability in order to measure delta13C and delta18O values and, simultaneously, the concentration of CO2 in sub-mL volume soil air samples. A sampling strategy designed for monitoring CO2 profiles at particular locations of interest is also described. This combined field and laboratory technique provides several advantages over those previously reported: (1) the small sample size required allows soil air to be sampled at a high spatial resolution, (2) the field setup minimizes sampling times and does not require powered equipment, (3) the analytical method avoids the introduction of air (including O2) into the mass spectrometer thereby extending filament life, and (4) pCO2, delta13C and delta18O are determined simultaneously. The reproducibility of measurements of CO2 in synthetic tank air using this technique is: +/-0.08 per thousand (delta13C), +/-0.10 per thousand (delta18O), and +/-0.7% (pCO2) at 5550 ppm. The reproducibility for CO2 in soil air is estimated as: +/-0.06 per thousand (delta13C), +/-0.06 per thousand (delta18O), and +/-1.6% (pCO2). Monitoring soil CO2 using this technique is applicable to studies concerning soil respiration and ecosystem gas exchange, the effect of elevated atmospheric CO2 (e.g. free air carbon dioxide enrichment) on soil processes, soil water budgets including partitioning evaporation from transpiration, pedogenesis and weathering, diffuse solid-earth degassing, and the calibration of speleothem and pedogenic carbonate delta13C values as paleoenvironmental proxies.

  6. Trading Off Global Fuel Supply, CO2 Emissions and Sustainable Development

    PubMed Central

    Wagner, Liam; Ross, Ian; Foster, John; Hankamer, Ben

    2016-01-01

    The United Nations Conference on Climate Change (Paris 2015) reached an international agreement to keep the rise in global average temperature ‘well below 2°C’ and to ‘aim to limit the increase to 1.5°C’. These reductions will have to be made in the face of rising global energy demand. Here a thoroughly validated dynamic econometric model (Eq 1) is used to forecast global energy demand growth (International Energy Agency and BP), which is driven by an increase of the global population (UN), energy use per person and real GDP (World Bank and Maddison). Even relatively conservative assumptions put a severe upward pressure on forecast global energy demand and highlight three areas of concern. First, is the potential for an exponential increase of fossil fuel consumption, if renewable energy systems are not rapidly scaled up. Second, implementation of internationally mandated CO2 emission controls are forecast to place serious constraints on fossil fuel use from ~2030 onward, raising energy security implications. Third is the challenge of maintaining the international ‘pro-growth’ strategy being used to meet poverty alleviation targets, while reducing CO2 emissions. Our findings place global economists and environmentalists on the same side as they indicate that the scale up of CO2 neutral renewable energy systems is not only important to protect against climate change, but to enhance global energy security by reducing our dependence of fossil fuels and to provide a sustainable basis for economic development and poverty alleviation. Very hard choices will have to be made to achieve ‘sustainable development’ goals. PMID:26959977

  7. Trading Off Global Fuel Supply, CO2 Emissions and Sustainable Development.

    PubMed

    Wagner, Liam; Ross, Ian; Foster, John; Hankamer, Ben

    2016-01-01

    The United Nations Conference on Climate Change (Paris 2015) reached an international agreement to keep the rise in global average temperature 'well below 2°C' and to 'aim to limit the increase to 1.5°C'. These reductions will have to be made in the face of rising global energy demand. Here a thoroughly validated dynamic econometric model (Eq 1) is used to forecast global energy demand growth (International Energy Agency and BP), which is driven by an increase of the global population (UN), energy use per person and real GDP (World Bank and Maddison). Even relatively conservative assumptions put a severe upward pressure on forecast global energy demand and highlight three areas of concern. First, is the potential for an exponential increase of fossil fuel consumption, if renewable energy systems are not rapidly scaled up. Second, implementation of internationally mandated CO2 emission controls are forecast to place serious constraints on fossil fuel use from ~2030 onward, raising energy security implications. Third is the challenge of maintaining the international 'pro-growth' strategy being used to meet poverty alleviation targets, while reducing CO2 emissions. Our findings place global economists and environmentalists on the same side as they indicate that the scale up of CO2 neutral renewable energy systems is not only important to protect against climate change, but to enhance global energy security by reducing our dependence of fossil fuels and to provide a sustainable basis for economic development and poverty alleviation. Very hard choices will have to be made to achieve 'sustainable development' goals.

  8. Comparing observations of fossil fuel-derived CO2 in California with predictions from bottom-up inventories

    NASA Astrophysics Data System (ADS)

    Graven, H. D.; Lueker, T.; Fischer, M. L.; Guilderson, T. P.; Keeling, R. F.; Brophy, K.; Arnold, T.; Bambha, R.; Callahan, W.; Campbell, J. E.; Frankenberg, C.; Hsu, Y.; Iraci, L. T.; Jeong, S.; Kim, J.; LaFranchi, B. W.; Lehman, S.; Manning, A.; Michelsen, H. A.; Miller, J. B.; Newman, S.; Parazoo, N.; Sloop, C.; Walker, S.; Whelan, M.; Wunch, D.

    2015-12-01

    The US state of California has a progressive climate change mitigation policy, AB-32, enacted in 2006 to reduce greenhouse gas emissions 15% by 2020 and then a further 80% by 2050. Bottom-up inventories indicate California's fossil fuel CO2 emissions are currently about 100 Mt C per year, but different inventories show discrepancies of ±15% in the state-wide total, and some larger discrepancies in various sub-regions of the state. We are developing a top-down framework for investigating fossil fuel and biospheric CO2 fluxes in California using atmospheric observations and models. California has a relatively dense collaborative network of greenhouse gas observations run by several universities, government laboratories and Earth Networks. Using this collaborative network, we conducted three field campaigns in 2014-15 to sample flasks at 10 tower sites across the state. Flasks were analysed for atmospheric CO2 and CO concentrations and for stable isotopes and radiocarbon in CO2. The flask observations of radiocarbon in CO2 allow patterns of fossil fuel-derived and biospheric CO2 to be distinguished at relatively high resolution across the state. We will report initial results from the observations showing regional gradients in fossil fuel-derived CO2 and fluctuations from changing weather patterns. We will compare the observations of fossil fuel-derived CO2 to predictions from several bottom-up inventories and two atmospheric models. Linking the flask data with observations from OCO-2, TCCON, aircraft flights and ground-based in situ analyzers, we will examine the variation in total CO2 and its drivers over California. Further analysis is planned to integrate the data into an inversion framework for fossil fuel and biospheric CO2 fluxes over California.

  9. Monitoring of Injected CO2 at Geologic CO2 Storage Demonstration Sites with Significant Pressure Depletion and/or Re-Pressurization Histories

    NASA Astrophysics Data System (ADS)

    Saini, D.

    2016-12-01

    Majority of geologic CO2 storage sites for currently operated large-scale integrated carbon capture and storage projects (LSIPs) in operation around the world are depleted oil fields that have been undergone significant depletion and re-pressurization prior to injection of captured CO2. A better understanding of any of the implications associated with past depletion and re-pressurization histories to "out of injection zone" migration of injected CO2 can help in making monitoring strategies significantly more effective. Being the geologic CO2 storage demonstration sites for two most active LSIPs in the US, the West Hastings and the Bell Creek Oil Fields are the main focus of present study. The monitoring technologies that have been used/deployed/tested at both the normally pressured West Hastings and subnormally pressured Bell Creek storage sites appear to adequately address any of the potential "out of zone migration" of injected CO2 at these sites. It would be interesting to see if any of the collected monitoring data at the West Hastings and the Bell Creek storage sites could also be used in future to better understand the viability of initially subnormally pressured and subsequently depleted and re-pressurized oil fields as secure geologic CO2 storage sites with relatively large storage CO2 capacities compared to the depleted and re-pressurized oil fields that were initially discovered as normally pressured.

  10. Geochemical monitoring of Taal volcano (Philippines) by means of diffuse CO2 degassing studies

    NASA Astrophysics Data System (ADS)

    Padrón, Eleazar; Hernández, Pedro A.; Arcilla, Carlo; Pérez, Nemesio M.; Lagmay, Alfredo M.; Rodríguez, Fátima; Quina, Gerald; Alonso, Mar; Padilla, Germán D.; Aurelio, Mario A.

    2017-04-01

    Observing changes in the discharge rate of CO2 is an important part of volcanic monitoring programs, because it is released by progressive depressurization of magma during ascent and reach the surface well before their parental magma. Taal Volcano in Southwest Luzon, Philippines, lies between a volcanic arc front facing the subduction zone along the Manila Trench and a volcanic field formed from extension beyond the arc front. Taal Volcano Island is formed by a main tuff cone surrounded by several smaller tuff cones, tuff rings and scoria cones. This island is located in the center of the 30 km wide Taal Caldera, now filled by Taal Lake. To monitor the volcanic activity of Taal volcano is a priority task in the Philippines, because several million people live within a 20-km radius of Taal's caldera rim. During the last period of volcanic unrest from 2010 to 2011, the main crater lake of Taal volcano released the highest diffuse CO2 emission rates through the water surface reported to date by volcanic lakes worldwide. The maximum CO2 emission rate measured in the study period occurred two months before the strongest seismic activity recorded during the unrest period (Arpa et al., 2013, Bull Volcanol 75:747). After the unrest period, diffuse CO2 emission has remained in the range 532-860 t/d in the period 2013-2016. In January 2016, an automatic geochemical station to monitor in a continuous mode the diffuse CO2 degassing in a selected location of Taal, was installed in January 2016 to improve the early warning system at the volcano. The station is located at Daang Kastila, at the northern portion of the main crater rim. It measures hourly the diffuse CO2 efflux, atmospheric CO2 concentration, soil water content and temperature, wind speed and direction, air temperature and humidity, rainfall, and barometric pressure. The 2016 time series show CO2 efflux values in the range 20-690 g m-2 d-1.Soil temperature, heavily influenced by rainfall, ranged between 74 and 96o

  11. [Open-path online monitoring of ambient atmospheric CO2 based on laser absorption spectrum].

    PubMed

    He, Ying; Zhang, Yu-Jun; Kan, Rui-Feng; Xia, Hui; Geng, Hui; Ruan, Jun; Wang, Min; Cui, Xiao-Juan; Liu, Wen-Qing

    2009-01-01

    With the conjunction of tunable diode laser absorption spectroscopy technology (TDLAS) and the open long optical path technology, the system designing scheme of CO2 on-line monitoring based on near infrared tunable diode laser absorption spectroscopy technology was discussed in detail, and the instrument for large-range measurement was set up. By choosing the infrared absorption line of CO2 at 1.57 microm whose line strength is strong and suitable for measurement, the ambient atmospheric CO2 was measured continuously with a 30 s temporal resolution at an suburb site in the autumn of 2007. The diurnal atmospheric variations of CO2 and continuous monitoring results were presented. The results show that the variation in CO2 concentration has an obvious diurnal periodicity in suburb where the air is free of interference and contamination. The general characteristic of diurnal variation is that the concentration is low in the daytime and high at night, so it matches the photosynthesis trend. The instrument can detect gas concentration online with high resolution, high sensitivity, high precision, short response time and many other advantages, the monitoring requires no gas sampling, the calibration is easy, and the detection limit is about 4.2 x 10(-7). It has been proved that the system and measurement project are feasible, so it is an effective method for gas flux continuous online monitoring of large range in ecosystem based on TDLAS technology.

  12. Large Hybrid Energy Systems for Making Low CO2 Load-Following Power and Synthetic Fuel

    SciTech Connect

    Robert S. Cherry; Richard D. Boardman; Steven Aumeier

    2012-02-01

    Hybrid energy systems using nuclear heat sources can economically produce load-following electrical power by exploiting the surplus generation capacity available at night or seasonally to make synthetic fuel. Vehicle fuel is the only current energy use large enough to absorb all the energy capacity that might be diverted from the power industry, and its ease of storage obviates problems with discontinuous synfuel production. The potential benefits and challenges of synfuels integration are illustrated by the production of methanol from natural gas (as a source of carbon) using steam from a light water nuclear power reactor which is assumed to be available in accord with a year's worth of power demand data. Methanol's synthesis process is easily adapted to using 300 C heat from a light water reactor and this simple compound can be further processed into gasoline, biodiesel, or dimethyl ether, fuels which can be used with the current vehicle fleet. A supplemental feed to the methanol process of natural gas (for energy) allows operation at constant full rate when the nuclear heat is being used to produce electrical power. The higher capital costs of such a system are offset by a lower cost of heat and power production from a large base load type of plant and by reduced costs associated with much lower CO2 emissions. Other less tangible economic benefits of this and similar hybrid systems include better use of natural resource for fuels and greater energy services security from the domestic production of vehicle fuel.

  13. Monitoring CO2 Intrusion in shallow aquifer using complex electrical methods and a novel CO2 sensitive Lidar-based sensor

    NASA Astrophysics Data System (ADS)

    Leger, E.; Dafflon, B.; Thorpe, M.; Kreitinger, A.; Laura, D.; Haivala, J.; Peterson, J.; Spangler, L.; Hubbard, S. S.

    2016-12-01

    While subsurface storage of CO2 in geological formations offers significant potential to mitigate atmospheric greenhouse gasses, approaches are needed to monitor the efficacy of the strategy as well as possible negative consequences, such as leakage of CO2 or brine into groundwater or release of fugitive gaseous CO2. Groundwater leakages can cause subsequent reactions that may also be deleterious. For example, a release of dissolved CO2 into shallow groundwatersystems can decrease groundwater pH which can potentiallymobilize naturally occurring trace metals and ions. In this perspective, detecting and assessing potential leak requires development of novel monitoring techniques.We present the results of using surface electrical resistivity tomography (ERT) and a novel CO2 sensitive Lidar-based sensor to monitor a controlled CO2 release at the ZeroEmission Research and Technology Center (Bozeman, Montana). Soil temperature and moisture sensors, wellbore water quality measurements as well as chamber-based CO2 flux measurements were used in addition to the ERT and a novel Lidar-based sensor to detect and assess potential leakage into groundwater, vadose zone and atmosphere. The three-week release wascarried out in the vadose and the saturated zones. Well sampling of pH and conductivity and surface CO2 fluxes and concentrations measurements were acquired during the release and are compared with complex electricalresistivity time-lapse measurements. The novel Lidar-based image of the CO2 plume were compared to chamber-based CO2 flux and concentration measurements. While a continuous increase in subsurface ERT and above ground CO2 was documented, joint analysis of the above and below ground data revealed distinct transport behavior in the vadose and saturated zones. Two type of transport were observed, one in the vadoze zone, monitored by CO2 flux chamber and ERT, and the other one in the saturated zone, were ERT and wellsampling were carried. The experiment suggests how

  14. Anion-activated, thermoreversible gelation system for the capture, release, and visual monitoring of CO2

    PubMed Central

    Zhang, Xin; Lee, Songyi; Liu, Yifan; Lee, Minji; Yin, Jun; Sessler, Jonathan L.; Yoon, Juyoung

    2014-01-01

    Carbon dioxide (CO2) is an important green house gas. This is providing an incentive to develop new strategies to detect and capture CO2. Achieving both functions within a single molecular system represents an unmet challenge in terms of molecular design and could translate into enhanced ease of use. Here, we report an anion-activated chemosensor system, NAP-chol 1, that permits dissolved CO2 to be detected in organic media via simple color changes or through ratiometric differences in fluorescence intensity. NAP-chol 1 also acts as a super gelator for DMSO. The resulting gel is transformed into a homogeneous solution upon exposure to fluoride anions. Bubbling with CO2 regenerates the gel. Subsequent flushing with N2 or heating serves to release the CO2 and reform the sol form. This series of transformations is reversible and can be followed by easy-to-discern color changes. Thus, NAP-chol 1 allows for the capture and release of CO2 gas while acting as a three mode sensing system. In particular, it permits CO2 to be detected through reversible sol-gel transitions, simple changes in color, or ratiometric monitoring of the differences in the fluorescence features. PMID:24699626

  15. Anion-activated, thermoreversible gelation system for the capture, release, and visual monitoring of CO2

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Lee, Songyi; Liu, Yifan; Lee, Minji; Yin, Jun; Sessler, Jonathan L.; Yoon, Juyoung

    2014-04-01

    Carbon dioxide (CO2) is an important green house gas. This is providing an incentive to develop new strategies to detect and capture CO2. Achieving both functions within a single molecular system represents an unmet challenge in terms of molecular design and could translate into enhanced ease of use. Here, we report an anion-activated chemosensor system, NAP-chol 1, that permits dissolved CO2 to be detected in organic media via simple color changes or through ratiometric differences in fluorescence intensity. NAP-chol 1 also acts as a super gelator for DMSO. The resulting gel is transformed into a homogeneous solution upon exposure to fluoride anions. Bubbling with CO2 regenerates the gel. Subsequent flushing with N2 or heating serves to release the CO2 and reform the sol form. This series of transformations is reversible and can be followed by easy-to-discern color changes. Thus, NAP-chol 1 allows for the capture and release of CO2 gas while acting as a three mode sensing system. In particular, it permits CO2 to be detected through reversible sol-gel transitions, simple changes in color, or ratiometric monitoring of the differences in the fluorescence features.

  16. Monitoring of environmental parameters for CO2 sequestration: a case study of Nagpur City, India.

    PubMed

    Chaudhari, P R; Gajghate, D G; Dhadse, Sharda; Suple, Sonali; Satapathy, D R; Wate, S R

    2007-12-01

    Carbon dioxide concentration is an index of total amount of combustion and natural ventilation in an urban environment and therefore required more careful attention for assessment of CO(2) level in air environment. An attempt was made to monitor CO(2) levels in ambient air of Nagpur city at industrial, commercial and residential sites. In addition to this a remote sensing studies and biotic survey for floral biodiversity were carried out to study the green cover at respective sampling locations. The observations showed that the largest amount of CO(2) occurred at night due to absence of photosynthesis and lowest concentration of CO(2) was observed in the afternoon due to photosynthesis at its maximum level. The most pollution tolerant species found in Nagpur city are having higher Air Pollution Tolerance Index (APTI) value, which acts as a natural sink for CO(2) sequestration. In case of commercial site the CO(2) level is highest (366 ppm) because of lowest vegetation and vehicular pollution. The generation of database of CO(2) concentration and floral biodiversity along with percentage of green cover helps to formulate the strategy for prevention of global worming phenomenon.

  17. Monitoring CO2 sequestration with a network inversion InSAR method

    NASA Astrophysics Data System (ADS)

    Rabus, B.; Ghuman, P.; MacDonald, B.

    2009-05-01

    The capture, containment and long-term storage of CO2 is increasingly discussed as an important means to counter climate change resulting from the ongoing release of greenhouse gases into the atmosphere. This CO2 sequestration often requires the pumping of the gas into deep saline aquifers. However, before sequestration can be regarded as a longterm solution it is necessary to investigate under which conditions permanent and leakless capture of the CO2 is achieved in the substrate. We demonstrate that a combination of spaceborne synthetic aperture interferometry (InSAR) and ground based measurements of ground uplift caused by the underground release and spreading of the CO2 can be forged into a powerful tool to monitor sequsetration. We use a novel InSAR approach, which combines the benefits of a point-based persistent scatterer algorithm with a network inversion approach, and an additional temporal filter to remove atmospheric disturbances also at smaller scales down to 1 km and less. Using case studies from several injection wells we show that InSAR and ground based data in conjunction with geological and structural information above the aquifer, as well as detailed injection logs, allow to monitor the volumetric spread of CO2 at the mm per year level. For the majority of the studied wells CO2 appears to approach a stable sequestration state, however, in at least one case our results suggest leakage outside the aquifer.

  18. Microbial monitoring during CO2 storage in deep subsurface saline aquifers in Ketzin, Germany

    NASA Astrophysics Data System (ADS)

    Wuerdemann, H.; Wandrey, M.; Fischer, S.; Zemke, K.; Let, D.; Zettlitzer, M.; Morozova, D.

    2010-12-01

    Investigations on subsurface saline aquifers have shown an active biosphere composed of diverse groups of microorganisms in the subsurface. Since microorganisms represent very effective geochemical catalysts, they may influence the process of CO2 storage significantly. In the frames of the EU Project CO2SINK a field laboratory to study CO2 storage into saline aquifer was operated. Our studies aim at monitoring of biological and biogeochemical processes and their impact on the technical effectiveness of CO2 storage technique. The interactions between microorganisms and the minerals of both the reservoir and the cap rock may cause changes to the structure and chemical composition of the rock formations, which may influence the reservoir permeability locally. In addition, precipitation and corrosion may be induced around the well affecting the casing and the casing cement. Therefore, analyses of the composition of microbial communities and its changes should contribute to an evaluation of the effectiveness and reliability of the long-term CO2 storage technique. In order to investigate processes in the deep biosphere caused by the injection of supercritical CO2, genetic fingerprinting (PCR SSCP Single-Strand-Conformation Polymorphism) and FISH (Fluorescence in situ Hybridisation) were used for identification and quantification of microorganisms. Although saline aquifers could be characterised as an extreme habitat for microorganisms due to reduced conditions, high pressure and salinity, a high number of diverse groups of microorganisms were detected with downhole sampling in the injection and observation wells at a depth of about 650m depth. Of great importance was the identification of the sulphate reducing bacteria, which are known to be involved in corrosion processes. Microbial monitoring during CO2 injection has shown that both quantity and diversity of microbial communities were strongly influenced by the CO2 injection. In addition, the indigenous microbial

  19. Monitoring Concept for CO2 Storage at the Pilot Site Ketzin, Germany

    NASA Astrophysics Data System (ADS)

    Wipki, Mario; Liebscher, Axel; Lüth, Stefan; Ivanova, Alexandra; Möller, Fabian; Schmidt-Hattenberger, Cornelia; Rippe, Dennis; Zimmer, Martin; Szizybalski, Alexandra

    2016-04-01

    Between 2008 and 2013, the German Research Centre for Geosciences - GFZ has injected more than 67 kt of CO2 at the Pilot Site in Ketzin, 25 km west of Berlin. The CO2 was stored in porous sandstones of the Upper Triassic Stuttgart Formation at a depth of 630 to 650 m. In more than a decade, GFZ has developed and tested an extraordinary multi-monitoring concept for onshore CO2 storages which mainly comprises the following methods: Time-lapse 3D seismic surveying is the most commonly used method for imaging and monitoring a CO2-plume in the deep underground before, during and after the injection phase. Such campaigns require high logistical and financial efforts and can be realised only to a limited extent. At Ketzin, for instance, 3D-seismic repeat surveys were acquired using several thousand surface acquisition points and lasting over two or three months. Alternative approaches include permanently buried seismic receivers. Geoelectric measurements in Ketzin are mainly applied by using a permanent downhole electrode installation (Vertical Electrical Resistivity Array = VERA) which has been implemented in three wells behind the well casings. Measurements between 590 m to 735 m are constantly carried out covering the vertical thickness of the entire CO2 storage horizon. Valuable results were achieved by a combination of inhole, crosshole and surface downhole measurements which has been carried out with appropriate acquisition geometries. For focused areas around monitoring wells, geoelectric methods may support and supplement information from seismic surveys. Borehole monitoring of pressure and temperature are generally indispensable for every underground gas storage type. In Ketzin, a remote monitoring system for all wells has been installed that constantly provides the operators with values for date, time, downhole and wellhead pressure, depth, and temperature. Moreover, all wellheads are checked weekly during onsite inspections. Samples for chemical analysis are

  20. Toward verifying fossil fuel CO2 emissions with the CMAQ model: motivation, model description and initial simulation.

    PubMed

    Liu, Zhen; Bambha, Ray P; Pinto, Joseph P; Zeng, Tao; Boylan, Jim; Huang, Maoyi; Lei, Huimin; Zhao, Chun; Liu, Shishi; Mao, Jiafu; Schwalm, Christopher R; Shi, Xiaoying; Wei, Yaxing; Michelsen, Hope A

    2014-04-01

    Motivated by the question of whether and how a state-of-the-art regional chemical transport model (CTM) can facilitate characterization of CO2 spatiotemporal variability and verify CO2 fossil-fuel emissions, we for the first time applied the Community Multiscale Air Quality (CMAQ) model to simulate CO2. This paper presents methods, input data, and initial results for CO2 simulation using CMAQ over the contiguous United States in October 2007. Modeling experiments have been performed to understand the roles of fossil-fuel emissions, biosphere-atmosphere exchange, and meteorology in regulating the spatial distribution of CO2 near the surface over the contiguous United States. Three sets of net ecosystem exchange (NEE) fluxes were used as input to assess the impact of uncertainty of NEE on CO2 concentrations simulated by CMAQ. Observational data from six tall tower sites across the country were used to evaluate model performance. In particular, at the Boulder Atmospheric Observatory (BAO), a tall tower site that receives urban emissions from Denver CO, the CMAQ model using hourly varying, high-resolution CO2 fossil-fuel emissions from the Vulcan inventory and Carbon Tracker optimized NEE reproduced the observed diurnal profile of CO2 reasonably well but with a low bias in the early morning. The spatial distribution of CO2 was found to correlate with NO(x), SO2, and CO, because of their similar fossil-fuel emission sources and common transport processes. These initial results from CMAQ demonstrate the potential of using a regional CTM to help interpret CO2 observations and understand CO2 variability in space and time. The ability to simulate a full suite of air pollutants in CMAQ will also facilitate investigations of their use as tracers for CO2 source attribution. This work serves as a proof of concept and the foundation for more comprehensive examinations of CO2 spatiotemporal variability and various uncertainties in the future. Atmospheric CO2 has long been modeled

  1. A Feasibility Study of Non-Seismic Geophysical Methods forMonitoring Geologic CO2 Sequestration

    SciTech Connect

    Gasperikova, Erika; Hoversten, G. Michael

    2006-07-01

    Because of their wide application within the petroleumindustry it is natural to consider geophysical techniques for monitoringof CO2 movement within hydrocarbon reservoirs, whether the CO2 isintroduced for enhanced oil/gas recovery or for geologic sequestration.Among the available approaches to monitoring, seismic methods are by farthe most highly developed and applied. Due to cost considerations, lessexpensive techniques have recently been considered. In this article, therelative merits of gravity and electromagnetic (EM) methods as monitoringtools for geological CO2 sequestration are examined for two syntheticmodeling scenarios. The first scenario represents combined CO2 enhancedoil recovery (EOR) and sequestration in a producing oil field, theSchrader Bluff field on the north slope of Alaska, USA. The secondscenario is a simplified model of a brine formation at a depth of 1,900m.

  2. Assessment of CO2 Injection Potential and Monitoring Well Location at the Mountaineer Power Plant Site

    SciTech Connect

    Bacon, Diana H.; White, Mark D.; Gupta, Neeraj; Sminchak, Joel R.; Kelley, Mark E.

    2006-11-01

    Numerical simulations of CO2 injection have been conducted as part of a program to assess the potential for geologic sequestration in a deep brine reservoir at the American Electric Power?s (AEP?s) Mountaineer Power Plant in New Haven, West Virginia. The results of the simulations will provide design guidance for injection and monitoring strategies, protocols, and permits for a demonstration project for CO2 injection in these deep saline aquifers as well as support for integrated risk assessments. The results of several three-dimensional simulations of CO2 injection into the Rose Run formation indicate that the formation is capable of receiving 666 to 837 ktonnes of CO2 at an injection pressure gradient of 1.53x104 Pa/m (0.675 psi/ft) over a period of 3 years.

  3. Initial results from seismic monitoring at the Aquistore CO2 storage site, Saskatchewan, Canada

    DOE PAGES

    White, D. J.; Roach, L. A.N.; Roberts, B.; ...

    2014-12-31

    The Aquistore Project, located near Estevan, Saskatchewan, is one of the first integrated commercial-scale CO2 storage projects in the world that is designed to demonstrate CO2 storage in a deep saline aquifer. Starting in 2014, CO2 captured from the nearby Boundary Dam coal-fired power plant will be transported via pipeline to the storage site and to nearby oil fields for enhanced oil recovery. At the Aquistore site, the CO2 will be injected into a brine-filled sandstone formation at ~3200 m depth using the deepest well in Saskatchewan. The suitability of the geological formations that will host the injected CO2 hasmore » been predetermined through 3D characterization using high-resolution 3D seismic images and deep well information. These data show that 1) there are no significant faults in the immediate area of the storage site, 2) the regional sealing formation is continuous in the area, and 3) the reservoir is not adversely affected by knolls on the surface of the underlying Precambrian basement. Furthermore, the Aquistore site is located within an intracratonic region characterized by extremely low levels of seismicity. This is in spite of oil-field related water injection in the nearby Weyburn-Midale field where a total of 656 million m3 of water have been injected since the 1960`s with no demonstrable related induced seismicity. A key element of the Aquistore research program is the further development of methods to monitor the security and subsurface distribution of the injected CO2. Toward this end, a permanent areal seismic monitoring array was deployed in 2012, comprising 630 vertical-component geophones installed at 20 m depth on a 2.5x2.5 km regular grid. This permanent array is designed to provide improved 3D time-lapse seismic imaging for monitoring subsurface CO2. Prior to the onset of CO2 injection, calibration 3D surveys were acquired in May and November of 2013. Comparison of the data from these surveys relative to the baseline 3D survey data

  4. On the influence of biomass burning on the seasonal CO2 signal as observed at monitoring stations

    USGS Publications Warehouse

    Wittenberg, U.; Heimann, Martin; Esse, G.; McGuire, A.D.; Sauf, W.

    1998-01-01

    We investigated the role of biomass burning in simulating the seasonal signal in both prognostic and diagnostic analyses. The prognostic anaysis involved the High-Resolution Biosphere Model, a prognostic terrestrial biosphere model, and the coupled vegetation fire module, which together produce a prognostic data set of biomass burning. The diagnostic analysis invovled the Simple Diagnostic Biosphere Model (SDBM) and the Hao and Liu [1994] diagnostic data set of bimass burning, which have been scaled to global 2 and 4 Pg C yr-1, respectively. The monthly carbon exchange fields between the atmosphere and the biosphere with a spatial resolution of 0.5?? ?? 0.5??, the seasonal atmosphere-ocean exchange fields, and the emissions from fossil fuels have been coupled to the three-dimensional atmospheric transport model TM2. We have chosen eight monitoring stations of the National Oceanic and Atmospheric Administration network to compare the predicted seasonal atmospheric CO2 signals with those deduced from atmosphere-biosphere carbon exchange fluxes without any contribution from biomass burning. The prognostic analysis and the diagnostic analysis with global burning emissions of 4 Pg C yr-1 agree with respect to the change in the amplitude of the seasonal CO2 concentration introduced through biomass burning. We find that the seasonal CO2 signal at stations in higher northern latitudes (north of 30??N) is marginally influenced by biomass burning. For stations in tropical regions an increase in the CO2 amplitude of more an 1 oppmv (up to 50% with respect to the observed trough to peak amplitude) has been calculated. Biomass burning at stations farther south accounts for an increase in the CO2 amplitude of up to 59% (0.6 ppmv). A change in the phase of the seasonal CO2 signal at tropical and southern stations has been shown to be strongly influenced by the onset of biomass burning in southern tropical Africa and America. Comparing simulated and observed seasonal CO2 signals

  5. Detection of endobronchial intubation by monitoring the CO2 level above the endotracheal cuff.

    PubMed

    Efrati, Shai; Deutsch, Israel; Weksler, Nathan; Gurman, Gabriel M

    2015-02-01

    Early detection of accidental endobronchial intubation (EBI) is still an unsolved problem in anesthesia and critical care daily practice. The aim of this study was to evaluate the ability of monitoring above cuff CO2 to detect EBI (the working hypothesis was that the origin of CO2 is from the unventilated, but still perfused, lung). Six goats were intubated under general anesthesia and the ETT positioning was verified by a flexible bronchoscope. The AnapnoGuard system, already successfully used to detect air leak around the ETT cuff, was used for continuous monitoring of above-the-cuff CO2 level. When the ETT distal tip was located in the trachea, with an average cuff pressure of 15 mmHg, absence of CO2 above the cuff was observed. The ETT was then deliberately advanced into one of the main bronchi under flexible bronchoscopic vision. In all six cases the immediate presence of CO2 above the cuff was identified. Further automatic inflation of the cuff, up to a level of 27 mmHg, did not affect the above-the-cuff measured CO2 level. Withdrawal of the ETT and repositioning of its distal tip in mid-trachea caused the disappearance of CO2 above the cuff in a maximum of 3 min, confirming the absence of air leak and the correct positioning of the ETT. Our results suggest that measurement of the above-the-cuff CO2 level could offer a reliable, on-line solution for early identification of accidental EBI. Further studies are planned to validate the efficacy of the method in a clinical setup.

  6. Design and construction of Information Systems of Ocean Satellite Monitoring for Air-sea CO2 Flux (IssCO2)

    NASA Astrophysics Data System (ADS)

    Zhu, Qiankun; Fang, Lei; Bai, Yan; He, Xianqiang; Sun, Xiaoxiao; Chen, Jianyu

    2013-10-01

    Climate change has become one of the hotspots of global attention in recent progress of globalization and industrialization. The mainstream opinion presented by Intergovernmental Panel on Climate Change (IPCC) regards that the global warming was caused mainly by greenhouse gases generated by human activities, such as anthropogenic CO2, which also resulting in the high-frequent happening of abnormal climate events. Satellite remote sensing is an efficient and economic method for CO2 flux observation. In this paper, we describe an Information System of Ocean Satellite Monitoring for Ari-sea CO2 Flux (IssCO2) which developed by the Second Institute of Oceanography, China. The IssCO2can achieve the whole procedure automatically from the satellite remote data receiving to products distribution, including the data acquirement and satellite image process, products generation, etc. The IssCO2 can process various types of in situ data, satellite data and model data, and validate the final satellite-derived CO2 flux products by in situ data; it can provide a real-time browsing and download of remote sensing products on the web based on the Geo-information System (GIS) technologies. The IssCO2 can meet the concurrent queries of different levels of users, and the query results can be visual displayed and analyzed on the client.

  7. Sensitivity of Flux Accuracy to Setup of Fossil Fuel and Biogenic CO2 Inverse System in an Urban Environment

    NASA Astrophysics Data System (ADS)

    Wu, K.; Lauvaux, T.; Deng, A.; Lopez-Coto, I.; Gurney, K. R.; Patarasuk, R.; Turnbull, J. C.; Davis, K. J.

    2015-12-01

    The Indianapolis Flux Experiment (INFLUX) aims to utilize a variety of measurements and a high resolution inversion system to estimate the spatial distribution and the temporal variation of anthropogenic greenhouse gas (GHG) emissions from the city of Indianapolis. We separated biogenic and fossil fuel CO2 fluxes and tested the sensitivity of inverse flux estimates to inverse system configurations by performing Observing System Simulation Experiments (OSSEs). The a priori CO2 emissions from Hestia were aggregated to 1 km resolution to represent emissions from the Indianapolis metropolitan area and its surroundings. With the Weather Research and Forecasting (WRF) model coupled to a Lagrangian Particle Dispersion Model (LPDM), the physical relations between concentrations at the tower locations and emissions at the surface were simulated at 1 km spatial resolution, hourly. Within a Bayesian synthesis inversion framework, we tested the effect of multiple parameters on our ability to infer fossil fuel CO2 fluxes: the presence of biogenic CO2 fluxes in the optimization procedure, the use of fossil fuel CO2 concentration measurements, the impact of reduced transport errors, the sensitivity to observation density, and the spatio-temporal properties of prior errors. The results indicate that the presence of biogenic CO2 fluxes obviously weakens the ability to invert for the fossil fuel CO2 emissions in an urban environment, but having relatively accurate fossil fuel CO2 concentration measurements can effectively compensate the interference from the biogenic flux component. Reduced transport error and more intensive measurement networks are two possible approaches to retrieve the spatial pattern of the fluxes and decrease the bias in inferred whole-city fossil fuel CO2 emissions. The accuracy of posterior fluxes is very sensitive to the spatial correlation length in the prior flux errors which, if they exist, can enhance significantly our ability to recover the known fluxes

  8. Quantification of fossil fuel CO2 at the building/street level for the LA Megacity

    NASA Astrophysics Data System (ADS)

    Gurney, K. R.; Razlivanov, I. N.; Patarasuk, R.; Song, Y.; O'Keeffe, D.; Duren, R. M.; Eldering, A.

    2013-12-01

    Quantification of fossil fuel CO2 emissions from the bottom-up perspective is a critical element in emerging plans on a global, integrated, carbon monitoring system (CMS). A space/time explicit emissions data product can act as both verification and guidance to emissions mitigation. We have progress on applying our Hestia approach to the entire LA Basin. Here, we present these initial results focusing on a few points of progress worthy of dissemination. Geocoding of the original point sources are inaccurate, placing point sources in the wrong physical position. Sometimes these errors are many kilometers. We have corrected the majority of these point through a variety of techniques. The LAX airport and the LA Port pose large unique sources in the Basin and we have taken novel approaches to characterizing the space/time distribution of these emission sources. We have used AADT and hourly traffic data to best distribute emissions in the onroad sector. This has required both extrapolation and interpolation techniques to fully cover all road types other than local roads. Finally, we have updated the emission product to the year 2012 using a variety of scaling arguments. Work on greenhouse gas emissions has been accomplished by others, though these efforts typically go down to only the county spatial scale. However, these offer numerous opportunities to potentially calibrate or explore alternative methods and results. We will review these efforts and what benefit they are provided thus far. Finally, we will review our attempts to quantify uncertainty at the space/time scales attempted here. Uncertainty quantification remains challenging due to a variety of reasons. First, bottom-up source data is often produced by a regulatory agency, which has strict legal limits to the amount and type of information available. Even in cases where legal limitations are not at work, there is no standard for uncertainty reporting and hence, little reliable uncertainty estimation is made

  9. Quantitative monitoring of subsurface CO2 emplacement and leakage using muon tomography

    NASA Astrophysics Data System (ADS)

    Coleman, M. L.; Kudryavtsev, V.; Spooner, N.; Gluyas, J.; Fung, C.

    2011-12-01

    Monitoring CO2 emplacement and possible leakage is a major challenge; methods, such as repeat seismic surveys, are episodic and expensive. A relevant alternative approach will use detection of cosmic ray muons, which has been used previously in archaeological and geological research as a technique for mapping features hidden underground. We developed a model to test if this concept would work for monitoring CO2 storage and show that muon detection is a viable method. To achieve this we used the well-established MUSUN/MUSIC computer codes to model changes in muon fluxes resulting from the introduction of supercritical CO2 into a simulated sandstone reservoir. Results from our first simulation indicate that we could detect as little as 0.4% change in the mean reservoir density at about 1 km depth, resulting from changing the relative proportions of CO2 and existing brine pore fluid. This change is equivalent to 7% of the pore volume in this particular case. However, other scenarios offer the promise of considerable increase in sensitivity. We will show how practical implementation can be achieved using state of the art drilling technology to place an array of detectors in short-radius side-track horizontal wells beneath the storage site. We conclude that with an appropriate design it will be possible to monitor and image the migration or loss of injected CO2 continuously using cosmic ray muons, a significant step towards implementing widescale CCS safely and help rapid introduction of this essential technology.

  10. Wavelet-based reconstruction of fossil-fuel CO2 emissions from sparse measurements

    NASA Astrophysics Data System (ADS)

    McKenna, S. A.; Ray, J.; Yadav, V.; Van Bloemen Waanders, B.; Michalak, A. M.

    2012-12-01

    We present a method to estimate spatially resolved fossil-fuel CO2 (ffCO2) emissions from sparse measurements of time-varying CO2 concentrations. It is based on the wavelet-modeling of the strongly non-stationary spatial distribution of ffCO2 emissions. The dimensionality of the wavelet model is first reduced using images of nightlights, which identify regions of human habitation. Since wavelets are a multiresolution basis set, most of the reduction is accomplished by removing fine-scale wavelets, in the regions with low nightlight radiances. The (reduced) wavelet model of emissions is propagated through an atmospheric transport model (WRF) to predict CO2 concentrations at a handful of measurement sites. The estimation of the wavelet model of emissions i.e., inferring the wavelet weights, is performed by fitting to observations at the measurement sites. This is done using Staggered Orthogonal Matching Pursuit (StOMP), which first identifies (and sets to zero) the wavelet coefficients that cannot be estimated from the observations, before estimating the remaining coefficients. This model sparsification and fitting is performed simultaneously, allowing us to explore multiple wavelet-models of differing complexity. This technique is borrowed from the field of compressive sensing, and is generally used in image and video processing. We test this approach using synthetic observations generated from emissions from the Vulcan database. 35 sensor sites are chosen over the USA. FfCO2 emissions, averaged over 8-day periods, are estimated, at a 1 degree spatial resolutions. We find that only about 40% of the wavelets in emission model can be estimated from the data; however the mix of coefficients that are estimated changes with time. Total US emission can be reconstructed with about ~5% errors. The inferred emissions, if aggregated monthly, have a correlation of 0.9 with Vulcan fluxes. We find that the estimated emissions in the Northeast US are the most accurate. Sandia

  11. Geophysical Signatures to Monitor Fluids and Mineralization for CO2 Sequestration in Basalts

    NASA Astrophysics Data System (ADS)

    Otheim, L. T.; Adam, L.; Van Wijk, K.; Batzle, M. L.; Mcling, T. L.; Podgorney, R. K.

    2011-12-01

    Carbon dioxide sequestration in large reservoirs can reduce emissions of this green house gas into the atmosphere. Basalts are promising host rocks due to their volumetric extend, worldwide distribution, and recent observations that CO2-water mixtures react with basalt minerals to precipitate as carbonate minerals, trapping the CO2. The chemical reaction between carbonic acid and minerals rich in calcium, magnesium and iron precipitates carbonates in the pore space. This process would increase the elastic modulus and velocity of the rock. At the same time, the higher compressibility of CO2 over water changes the elastic properties of the rock, decreasing the saturated rock bulk modulus and the P-wave velocity. Reservoirs where the rock properties change as a result of fluid or pressure changes are commonly monitored with seismic methods. Here we present experiments to study the feasibility of monitoring CO2 migration in a reservoir and CO2-rock reactions for a sequestration scenario in basalts. Our goal is to measure the rock's elastic response to mineralization with non-contacting ultrasonic lasers, and the effect of fluid substitution at reservoir conditions at seismic and ultrasonic frequencies. For the fluid substitution experiment we observe changes in the P- and S-wave velocities when saturating the sample with super-critical (sc) CO2, CO2-water mixtures and water alone for different pore and confining pressures. The bulk modulus of the rock is significantly dependent on frequency in the 2~to 106~Hz range, for CO2-water mixtures and pure water saturations. Dry and pure CO2 (sc or gas) do not show a frequency dependence on the modulus. Moreover, the shear wave modulus is not dispersive for either fluid. The frequency dependence of the elastic parameters is related to the attenuation (1/Q) of the rock. We will show the correlation between frequency dependent moduli and attenuation data for the different elastic moduli of the rocks. Three other basalt samples

  12. Strategies for satellite-based monitoring of CO2 from distributed area and point sources

    NASA Astrophysics Data System (ADS)

    Schwandner, Florian M.; Miller, Charles E.; Duren, Riley M.; Natraj, Vijay; Eldering, Annmarie; Gunson, Michael R.; Crisp, David

    2014-05-01

    Atmospheric CO2 budgets are controlled by the strengths, as well as the spatial and temporal variabilities of CO2 sources and sinks. Natural CO2 sources and sinks are dominated by the vast areas of the oceans and the terrestrial biosphere. In contrast, anthropogenic and geogenic CO2 sources are dominated by distributed area and point sources, which may constitute as much as 70% of anthropogenic (e.g., Duren & Miller, 2012), and over 80% of geogenic emissions (Burton et al., 2013). Comprehensive assessments of CO2 budgets necessitate robust and highly accurate satellite remote sensing strategies that address the competing and often conflicting requirements for sampling over disparate space and time scales. Spatial variability: The spatial distribution of anthropogenic sources is dominated by patterns of production, storage, transport and use. In contrast, geogenic variability is almost entirely controlled by endogenic geological processes, except where surface gas permeability is modulated by soil moisture. Satellite remote sensing solutions will thus have to vary greatly in spatial coverage and resolution to address distributed area sources and point sources alike. Temporal variability: While biogenic sources are dominated by diurnal and seasonal patterns, anthropogenic sources fluctuate over a greater variety of time scales from diurnal, weekly and seasonal cycles, driven by both economic and climatic factors. Geogenic sources typically vary in time scales of days to months (geogenic sources sensu stricto are not fossil fuels but volcanoes, hydrothermal and metamorphic sources). Current ground-based monitoring networks for anthropogenic and geogenic sources record data on minute- to weekly temporal scales. Satellite remote sensing solutions would have to capture temporal variability through revisit frequency or point-and-stare strategies. Space-based remote sensing offers the potential of global coverage by a single sensor. However, no single combination of orbit

  13. [Monitoring and analysis of CO2 and CH4 using long path FTIR spectroscopy over Beijing].

    PubMed

    Xu, Liang; Liu, Jian-guo; Gao, Min-guang; Lu, Yi-huai; Liu, Wen-qing; Wei, Xiu-li; Zhu, Jun; Zhang, Tian-shu; Chen, Jun

    2007-05-01

    Recently, the greenhouse effect is well known and is of great worldwide concern. CO2 and CH4 are two of the main human activity-induced greenhouse gases in the atmosphere. It is important for environmental scientists to monitor their long-term variation. A Fourier transform infrared spectrometer was used to monitor the concentrations of CO2 and CH4 at a specific site in Beijing. The pollution air was passed through a long open path and the absorption spectra were collected over a period of a month. Quantitative analysis was performed by means of the nonlinear least square method using synthetically generated spectra, which was than convolved with instrumental line shape function. Ambient levels of CO2 and CH4 are reported with a time resolution of five minutes for 4-10, September 2005, and some analysis is present.

  14. A Vulnerability-Benefit Analysis of Fossil Fuel CO2 Emissions

    NASA Astrophysics Data System (ADS)

    Delman, E. M.; Stephenson, S. R.; Davis, S. J.; Diffenbaugh, N. S.

    2015-12-01

    Although we can anticipate continued improvements in our understanding of future climate impacts, the central challenge of climate change is not scientific, but rather political and economic. In particular, international climate negotiations center on how to share the burden of uncertain mitigation and adaptation costs. We expose the relative economic interests of different countries by assessing and comparing their vulnerability to climate impacts and the economic benefits they derive from the fossil fuel-based energy system. Vulnerability refers to the propensity of humans and their assets to suffer when impacted by hazards, and we draw upon the results from a number of prior studies that have quantified vulnerability using multivariate indices. As a proxy for benefit, we average CO2 related to each country's extraction of fossil fuels, production of CO2 emissions, and consumption of goods and services (Davis et al., 2011), which should reflect benefits accrued in proportion to national economic dependence on fossil fuels. We define a nondimensional vulnerability-benefit ratio for each nation and find a large range across countries. In general, we confirm that developed and emerging economies such as the U.S., Western Europe, and China rely heavily on fossil fuels and have substantial resources to respond to the impacts of climate change, while smaller, less-developed economies such as Sierra Leone and Vanuatu benefit little from current CO2 emissions and are much more vulnerable to adverse climate impacts. In addition, we identify some countries with a high vulnerability and benefit, such as Iraq and Nigeria; conversely, some nations exhibit both a low vulnerability and benefit, such as New Zealand. In most cases, the ratios reflect the nature of energy-climate policies in each country, although certain nations - such as the United Kingdom and France - assume a level of responsibility incongruous with their ratio and commit to mitigation policy despite

  15. Geochemical monitoring for detection of CO_{2} leakage from subsea storage sites

    NASA Astrophysics Data System (ADS)

    García-Ibáñez, Maribel I.; Omar, Abdirahman M.; Johannessen, Truls

    2017-04-01

    Carbon Capture and Storage (CCS) in subsea geological formations is a promising large-scale technology for mitigating the increases of carbon dioxide (CO2) in the atmosphere. However, detection and quantification of potential leakage of the stored CO2 remains as one of the main challenges of this technology. Geochemical monitoring of the water column is specially demanding because the leakage CO2 once in the seawater may be rapidly dispersed by dissolution, dilution and currents. In situ sensors capture CO2 leakage signal if they are deployed very close to the leakage point. For regions with vigorous mixing and/or deep water column, and for areas far away from the leakage point, a highly sensitive carbon tracer (Cseep tracer) was developed based on the back-calculation techniques used to estimate anthropogenic CO2 in the water column. Originally, the Cseep tracer was computed using accurate discrete measurements of total dissolved inorganic carbon (DIC) and total alkalinity (AT) in the Norwegian Sea to isolate the effect of natural submarine vents in the water column. In this work we assess the effect of measurement variables on the performance of the method by computing the Cseep tracer twice: first using DIC and AT, and second using partial pressure of CO2 (pCO2) and pH. The assessment was performed through the calculation of the signal to noise ratios (STNR). We found that the use of the Cseep tracer increases the STNR ten times compared to the raw measurement data, regardless of the variables used. Thus, while traditionally the pH-pCO2 pair generates the greatest uncertainties in the oceanic CO2 system, it seems that the Cseep technique is insensitive to that issue. On the contrary, the use of the pCO2-pH pair has the highest CO2 leakage detection and localization potential due to the fact that both pCO2 and pH can currently be measured at high frequency and in an autonomous mode.

  16. Hydrogeological characterization of shallow-depth zone for CO2 injection and leak test at a CO2 environmental monitoring site in Korea

    NASA Astrophysics Data System (ADS)

    Lee, S. S.; Kim, T. W.; Kim, H. H.; Ha, S. W.; Jeon, W. T.; Lee, K. K.

    2015-12-01

    The main goal of the this study is to evaluate the importance of heterogeneities in controlling the field-scale transport of CO2 are originated from the CO2 injected at saturated zone below the water table for monitoring and prediction of CO2 leakage from a reservoir. Hydrogeological and geophysical data are collected to characterize the site, prior to conducting CO2 injection experiment at the CO2 environmental monitoring site at Eumseong, Korea. The geophysical data were acquired from borehole electromagnetic flowmeter tests, while the hydraulic data were obtained from pumping tests, slug tests, and falling head permeability tests. Total of 13 wells to perform hydraulic and geophysical test are established along groundwater flow direction in regular sequence, revealed by the results of borehole electromagnetic flowmeter test. The results of geophysical tests indicated that hydraulic gradient is not identical with the topographic gradient. Groundwater flows toward the uphill direction in the study area. Then, the hydraulic tests were conducted to identify the hydraulic properties of the study site. According to the results of pumping and slug tests at the study site, the hydraulic conductivity values show ranges between 4.75 x 10-5 cm/day and 9.74 x 10-5 cm/day. In addition, a portable multi-level sampling and monitoring packer device which remains inflated condition for a long period developed and used to isolate designated depths to identify vertical distribution of hydrogeological characteristics. Hydrogeological information obtained from this study will be used to decide the injection test interval of CO2-infused water and gaseous CO2. Acknowledgement: Financial support was provided by "R&D Project on Environmental Mangement of Geologic CO2 Storage" from the KEITI (Project Number: 2014001810003).

  17. Toward Verifying Fossil Fuel CO2 Emissions with the CMAQ Model: Motivation, Model Description and Initial Simulation

    SciTech Connect

    Liu, Zhen; Bambha, Ray P.; Pinto, Joseph P.; Zeng, Tao; Boylan, Jim; Huang, Maoyi; Lei, Huimin; Zhao, Chun; Liu, Shishi; Mao, Jiafu; Schwalm, Christopher R.; Shi, Xiaoying; Wei, Yaxing; Michelsen, Hope A.

    2014-03-14

    Motivated by the urgent need for emission verification of CO2 and other greenhouse gases, we have developed regional CO2 simulation with CMAQ over the contiguous U.S. Model sensitivity experiments have been performed using three different sets of inputs for net ecosystem exchange (NEE) and two fossil fuel emission inventories, to understand the roles of fossil fuel emissions, atmosphere-biosphere exchange and transport in regulating the spatial and diurnal variability of CO2 near the surface, and to characterize the well-known ‘signal-to-noise’ problem, i.e. the interference from the biosphere on the interpretation of atmospheric CO2 observations. It is found that differences in the meteorological conditions for different urban areas strongly contribute to the contrast in concentrations. The uncertainty of NEE, as measured by the difference among the three different NEE inputs, has notable impact on regional distribution of CO2 simulated by CMAQ. Larger NEE uncertainty and impact are found over eastern U.S. urban areas than along the western coast. A comparison with tower CO2 measurements at Boulder Atmospheric Observatory (BAO) shows that the CMAQ model using hourly varied and high-resolution CO2 emission from the Vulcan inventory and CarbonTracker optimized NEE reasonably reproduce the observed diurnal profile, whereas switching to different NEE inputs significantly degrades the model performance. Spatial distribution of CO2 is found to correlate with NOx, SO2 and CO, due to their similarity in emission sources and transport processes. These initial results from CMAQ demonstrate the power of a state-of-the art CTM in helping interpret CO2 observations and verify fossil fuel emissions. The ability to simulate CO2 in CMAQ will also facilitate investigations of the utility of traditionally regulated pollutants and other species as tracers to CO2 source attribution.

  18. Time lapse geoelectrical and geochemical monitoring of CO2 migration in a carbonate vadose zone - lessons learned from the CO2-Vadose and DEMO-CO2 projects (Saint Emilion, France).

    NASA Astrophysics Data System (ADS)

    Virgile, R.; Cerepi, A.; Garcia, B.; Delaplace, P.; Loisy, C.; Leroux, O.; Laveuf, C.; Cohen, G.; Rhino, K.; El Khamlichi, A.

    2016-12-01

    The surface and subsurface monitoring of underground CO2 leakage is a complex task because of the natural heterogeneities in the distribution of soil and substrate properties such as porosity, permeability, mineralogy, water saturation and organic content; together with diurnal and seasonal weather condition variations. The different potential migration pathways and mechanisms, and the local sources and sinks of free CO2 render the establishment of mass balance at the natural experiment scale very challenging; precluding robust impact assessment of CO2 leakage on the environment to be made. The CO2-Vadose and DEMO-CO2 projects aimed at building knowledge and methodologies for apprehending CO2 leakage in the context of a carbonate vadose zone. More than 6 years of experiments and technical developments have led to a refined understanding of the CO2 migration throughout a high porosity-permeability limestone formation, through the use of time-lapse geoelectric monitoring and geochemical tracers. Based on numerical simulations of fluid flow in porous media, a monitoring set up was designed with optimized probe placement and sampling calendars. CO2+tracer gas was injected in different locations of the experimental site, and gas compositions were monitored and the data interpreted in a common 4D reference frame. The comparison of the results from numerical simulations and leakage experiments allow to track advection and diffusion driven migrations, and preferential migration pathways in response to underground petrophysical heterogeneities. Building on the expertise gained from the development of the experimental site, a prototype of automated gas geochemistry monitoring was designed, built and put into operation. This presentation will guide you through the scientific and technical achievements of several years of experimental work in the underground quarries of the St Emilion village.

  19. VSP Monitoring of CO2 Injection at the Aneth Oil Field in Utah

    NASA Astrophysics Data System (ADS)

    Huang, L.; Rutledge, J.; Zhou, R.; Denli, H.; Cheng, A.; Zhao, M.; Peron, J.

    2008-12-01

    Remotely tracking the movement of injected CO2 within a geological formation is critically important for ensuring safe and long-term geologic carbon sequestration. To study the capability of vertical seismic profiling (VSP) for remote monitoring of CO2 injection, a geophone string with 60 levels and 96 channels was cemented into a monitoring well at the Aneth oil field in Utah operated by Resolute Natural Resources and Navajo National Oil and Gas Company. The oil field is located in the Paradox Basin of southeastern Utah, and was selected by the Southwest Regional Partnership on Carbon Sequestration, supported by the U.S. Department of Energy, to demonstrate combined enhanced oil recovery (EOR) and CO2 sequestration. The geophones are placed at depths from 805 m to 1704 m, and the oil reservoir is located approximately from 1731 m to 1786 m in depth. A baseline VSP dataset with one zero-offset and seven offset source locations was acquired in October, 2007 before CO2 injection. The offsets/source locations are approximately 1 km away from the monitoring well with buried geophone string. A time-lapse VSP dataset with the same source locations was collected in July, 2008 after five months of CO2/water injection into a horizontal well adjacent to the monitoring well. The total amount of CO2 injected during the time interval between the two VSP surveys was 181,000 MCF (million cubic feet), or 10,500 tons. The time-lapse VSP data are pre-processed to balance the phase and amplitude of seismic events above the oil reservoir. We conduct wave-equation migration imaging and interferometry analysis using the pre-processed time-lapse VSP data. The results demonstrate that time-lapse VSP surveys with high-resolution migration imaging and scattering analysis can provide reliable information about CO2 migration. Both the repeatability of VSP surveys and sophisticated time-lapse data pre-processing are essential to make VSP as an effective tool for monitoring CO2 injection.

  20. Monitoring of catalyst performance in CO2 lasers using frequency modulation spectroscopy with diode lasers

    NASA Technical Reports Server (NTRS)

    Wang, Liang-Guo; Sachse, Glen

    1990-01-01

    Closed-cycle CO2 laser operation with removal of O2 and regeneration of CO2 can be achieved by catalytic CO-O2 recombination. Both parametric studies of the optimum catalyst formulation and long-term performance tests require on line monitoring of CO, O2 and CO2 concentrations. There are several existing methods for molecular oxygen detection. These methods are either intrusive (such as electrochemical method or mass spectrometry) or very expensive (such as CARS, UV laser absorption). Researchers demonstrated a high-sensitivity spectroscopic measurement of O2 using the two-tone frequency modulation spectroscopy (FMS) technique with a near infrared GaAlAs diode laser. Besides its inexpensive cost, fast response time, nonintrusive measurements and high sensitivity, this technique may also be used to differentiate between isotopes due to its high spectroscopic resolution. This frequency modulation spectroscopy technique could also be applied for the on-line monitoring of CO and CO2 using InGaAsP diode lasers operation in the 1.55 microns region and H2O in the 1.3 microns region. The existence of single mode optical fibers at the near infrared region makes it possible to combine FMS with optical fiber technology. Optical fiber FMS is particularly suitable for making point-measurements at one or more locations in the CO2 laser/catalyst system.

  1. The utility of space-based CO2 emission mapping for monitoring emissions from cities

    NASA Astrophysics Data System (ADS)

    Oda, T.; Lauvaux, T.; Roman, M. O.; Wang, Z.; Tang, J.; Rao, P.

    2016-12-01

    Cities are responsible for more than 70% of greenhouse gas emissions in the world and their magnitude is rapidly changing in response to economic activities and emission reduction efforts. The science community is expected to provide a tool to monitor these emissions and guide practical emission management. When applying a top-down inversion to a city, the availability of detailed emission inventory is one of limiting factor other than atmospheric data. With a hope of getting more CO2 data collected by ongoing and future CO2 satellites (e.g. NASA's OCO2/OCO3), we started prototyping the use of satellite data to help constraining city emissions. The development of fine-grained emission dataset, which will be a prior for inversion, requires time-intensive labor and often difficult to update on annual basis. We made an attempt to improve the 1 km resolution fossil fuel emission fields taken from global nightlight-based emission model ODIAC using a 30m resolution impervious surface data. Impervious data is a good indicator of emitting areas in cities (e.g. building/road vs. urban vegetation) and should inform fine-scale emission source spatial structures. We implemented inversions using two different prior emissions (1km ODIAC emission field and the improved 30m emission field) and compared to the control inversion case where a fine-grained emission data was used. We confirmed that the use of two satellite-based emission fields both yield comparable emission estimates to the control. Also, the improved results from the run with the 30m emission field relative to the 1km ODIAC case, suggested that while temporal variations are captured by atmospheric inversions (emissions are only provided on monthly basis), emission spatial structures remain as a key information to constrain emission spatial distributions at a very fine spatial scale. The improved emission field can be also used to implement the full characterization of error structures, which is not currently

  2. Seismic modeling to monitor CO2 geological storage: The Atzbach-Schwanenstadt gas field

    NASA Astrophysics Data System (ADS)

    Picotti, Stefano; Carcione, José M.; Gei, Davide; Rossi, Giuliana; Santos, Juan E.

    2012-06-01

    We develop a petro-elastical numerical methodology to compute realistic synthetic seismograms and analyze the sensitivity of the seismic response when injecting carbon dioxide (CO2) in a depleted gas reservoir. The petro-elastical model describes the seismic properties of the reservoir rock saturated with CO2, methane and brine, and allows us to estimate the distribution and saturation of CO2 during the injection process. The gas properties, as a function of the in-situ pressure and temperature conditions, are computed with the Peng-Robinson equation of state, taking into account the absorption of gas by brine. Wave attenuation and velocity dispersion are based on the mesoscopic loss mechanism, which is simulated by an upscaling procedure to obtain an equivalent viscoelastic medium corresponding to partial saturation at the mesoscopic scale. Having the equivalent complex and frequency-dependent bulk (dilatational) modulus, we include shear attenuation and perform numerical simulations of wave propagation at the macroscale by solving the viscoelastic differential equations using the memory-variable approach. The pseudo-spectral modeling method allows general material variability and provides a complete and accurate characterization of the reservoir. The methodology is used to assess the sensitivity of the seismic method for monitoring the CO2 geological storage at the Atzbach-Schwanestadt depleted gas-field in Austria. The objective of monitoring is the detection of the CO2 plume in the reservoir and possible leakages of CO2. The leakages are located at different depths, where the CO2 is present as gaseous, liquid and supercritical phases. Even though the differences can be very subtle, this work shows that seismic monitoring of CO2 from the surface is possible. While the identification of shallow leakages is feasible, the detection of the plume and deep leakages, located in the caprock just above the injection formation, is more difficult, but possible by using

  3. Time Lapse Gravity and Seismic Monitoring of CO2 Injection at the West Hastings Field, Texas

    NASA Astrophysics Data System (ADS)

    Ferguson, J. F.; Richards, T.; Klopping, F.; MacQueen, J.; Hosseini, S. A.

    2015-12-01

    Time lapse or 4D gravity and seismic reflection surveys are being conducted at the West Hastings Field near Houston, Texas to monitor the progress of CO2 injection. This Department of Energy supported CO2 sequestration experiment is conducted in conjunction with a Denbury Onshore, LLC tertiary recovery project. The reservoir is at a depth of 1.8 km in the Oligocene Frio sands and has been produced since the 1930s. Goals are an accounting and mapping of the injected CO2 and to determine if migration occurs along intra-reservoir faults. An integrated interpretation of the geophysical surveys will be made together with well logs and engineering data. Gravity monitoring of water versus gas replacement has been very successful, but liquid phase CO2 monitoring is problematic due to the smaller density contrast with respect to oil and water. This reservoir has a small volume to depth ratio and hence only a small gravity difference signal is expected on the surface. New borehole gravity technology introduced by Micro-g-Lacoste can make gravity measurements at near reservoir depths with a much higher signal to noise ratio. This method has been successfully evaluated on a simulation of the Hastings project. Field operations have been conducted for repeated surface and borehole gravity surveys beginning in 2013. The surface survey of 95 stations covers an area of 3 by 5 km and 22 borehole gravity logs are run in the interval above the Frio formation. 4D seismic reflection surveys are being made at 6 month intervals on the surface and in 3 VSP wells. CO2 injection into the targeted portion of the reservoir only began in early 2015 and monitoring will continue into 2017. To date only the baseline reservoir conditions have been assessed. The overall success of the gravity monitoring will not be determined until 2017.

  4. Improved monitoring of subsurface CO2 storage using novel electrical and seismic measurements: scaled laboratory studies

    NASA Astrophysics Data System (ADS)

    Ghose, R.; Kirichek, A.; Draganov, D.; Heller, K.

    2013-05-01

    For monitoring CO2 stored in appropriate geological settings like depleted oil or gas reservoirs, deep saline aquifers and deep unminable coalbeds, geophysical methods e.g., seismic, electromagnetics, gravity, and surface deformation studies serve as remote sensing techniques which generally provide a large coverage but a low spatial resolution. It has been concluded that of the various approaches, seismic methods have the broadest applicability for stored CO2 monitoring in various geologic settings. As a result, advanced and dedicated seismic monitoring techniques have been developed. However, three major issues that remain unresolved are: 1) to remove accurately the effect of the overburden layers in order to capture the change in seismic properties in the reservoir and thereby obtain reliable estimates of temporal and spatial changes of the rock-physical properties like pressure and saturation, 2) the difficulty to minimize the source-related variation in time-lapse seismic, and 3) the inability to monitor the changes in phase (supercritical, liquid or gaseous) of the stored CO2 in time and space. In order to address these crucial issues, we have concentrated on scaled laboratory tests mimicking realistic storage conditions, and have tested novel approaches involving analysis of complex electrical impedance coupled with seismic-interferometric characterization. A new laboratory experimental facility for simultaneous, multichannel seismic and AC electrical measurements has been developed. We have found that electrical permittivity is a very sensitive parameter to monitor the phase of the stored CO2. Secondly, a novel approach has been developed, which takes advantage of the nonphysical reflections retrieved by seismic interferometry to estimate reliable values of seismic wave velocity and attenuation in the CO2 reservoir, efficiently minimizing the effect of the overburden and removing the detrimental effect of the source-related irreproducibility. Finally, new

  5. Permanent downhole fiber optic pressure and temperature monitoring during CO2 injection

    NASA Astrophysics Data System (ADS)

    Schmidt-Hattenberger, C.; Moeller, F.; Liebscher, A.; Koehler, S.

    2009-04-01

    Permanent downhole monitoring of pressure and temperature, ideally over the entire length of the injection string, is essential for any smooth and safe CO2 injection within the framework of geological CO2 storage: i) To avoid fracturing of the cap-rock, a certain, site dependent pressure threshold within the reservoir should not be exceeded; ii) Any CO2 phase transition within the injection string, i.e. either condensation or evaporation, should be avoided. Such phase transitions cause uncontrolled and undetermined P-T regimes within the injection string that may ultimately result in a shut-in of the injection facility; and iii) Precise knowledge of the P and T response of the reservoir to the CO2 injection is a prerequisite to any reservoir modeling. The talk will present first results from our permanent downhole P-T monitoring program from the Ketzin CO2 storage test site (CO2SINK). At Ketzin, a fiber Bragg grating pressure sensor has been installed at the end of the injection string in combination with distributed temperature profiling over the entire length (about 550 m) of the string for continuous P-T monitoring during operation. Such fiber optic monitoring technique is used by default in the oil and gas industry but has not yet been applied as standard on a long-term routine mode for CO2 injection. Pressure is measured every 5 seconds with a resolution of < 1 bar. The data are later processed by user-defined program. The temperature logs along the injection string are measured every 3 minutes with a spatial resolution of one meter and with a temperature resolution of about 0.1°C. The long-term stability under full operational conditions is currently under investigation. The main computer of the P-T system operates as a stand-alone data-acquisition unit, and is connected with a secure intranet in order to ensure remote data access and system maintenance. The on-line measurements are displayed on the operator panel of the injection facility for direct control

  6. Quantification of fossil fuel CO2 emissions at the urban scale: Results from the Indianapolis Flux Project (INFLUX)

    NASA Astrophysics Data System (ADS)

    Turnbull, J. C.; Cambaliza, M. L.; Sweeney, C.; Karion, A.; Newberger, T.; Tans, P. P.; Lehman, S.; Davis, K. J.; Miles, N. L.; Richardson, S.; Lauvaux, T.; Shepson, P.; Gurney, K. R.; Song, Y.; Razlivanov, I. N.

    2012-12-01

    Emissions of fossil fuel CO2 (CO2ff) from anthropogenic sources are the primary driver of observed increases in the atmospheric CO2 burden, and hence global warming. Quantification of the magnitude of fossil fuel CO2 emissions is vital to improving our understanding of the global and regional carbon cycle, and independent evaluation of reported emissions is essential to the success of any emission reduction efforts. The urban scale is of particular interest, because ~75% CO2ff is emitted from urban regions, and cities are leading the way in attempts to reduce emissions. Measurements of 14CO2 can be used to determine CO2ff, yet existing 14C measurement techniques require laborious laboratory analysis and measurements are often insufficient for inferring an urban emission flux. This presentation will focus on how 14CO2 measurements can be combined with those of more easily measured ancillary tracers to obtain high resolution CO2ff mixing ratio estimates and then infer the emission flux. A pilot study over Sacramento, California showed strong correlations between CO2ff and carbon monoxide (CO) and demonstrated an ability to quantify the urban flux, albeit with large uncertainties. The Indianapolis Flux Project (INFLUX) aims to develop and assess methods to quantify urban greenhouse gas emissions. Indianapolis was chosen as an ideal test case because it has relatively straightforward meteorology; a contained, isolated, urban region; and substantial and well-known fossil fuel CO2 emissions. INFLUX incorporates atmospheric measurements of a suite of gases and isotopes including 14C from light aircraft and from a network of existing tall towers surrounding the Indianapolis urban area. The recently added CO2ff content is calculated from measurements of 14C in CO2, and then convolved with atmospheric transport models and ancillary data to estimate the urban CO2ff emission flux. Significant innovations in sample collection include: collection of hourly averaged samples to

  7. Continuous monitoring of diffuse CO2 degassing at Taal volcano, Philippines

    NASA Astrophysics Data System (ADS)

    Padron, E.; Hernandez Perez, P. A.; Arcilla, C. A.; Lagmay, A. M. A.; Perez, N. M.; Quina, G.; Padilla, G.; Barrancos, J.; Cótchico, M. A.; Melián, G.

    2016-12-01

    Observing changes in the composition and discharge rates of volcanic gases is an important part of volcanic monitoring programs, because some gases released by progressive depressurization of magma during ascent are highly mobile and reach the surface well before their parental magma. Among volcanic gases, CO2 is widely used in volcano studies and monitoring because it is one of the earliest released gas species from ascending magma, and it is considered conservative. Taal Volcano in Southwest Luzon, Philippines, lies between a volcanic arc front (facing the subduction zone along the Manila Trench) and a volcanic field formed from extension beyond the arc front. Taal Volcano Island is formed by a main tuff cone surrounded by several smaller tuff cones, tuff rings and scoria cones. This island is located in the center of the 30 km wide Taal Caldera, now filled by Taal Lake. To monitor the volcanic activity of Taal volcano is a priority task in the Philippines, because several million people live within a 20-km radius of Taal's caldera rim. In the period from 2010-2011, during a period of volcanic unrest, the main crater lake of Taal volcano released the highest diffuse CO2 emission rates reported to date by volcanic lakes worldwide. The maximum CO2 emission rate measured in the study period occurred two months before the strongest seismic activity recorded during the unrest period (Arpa et al., 2013, Bull Volcanol 75:747). In the light of the excellent results obtained through diffuse degassing studies, an automatic geochemical station to monitor in a continuous mode the diffuse CO2 degassing in a selected location of Taal, was installed in January 2016 to improve the early warning system at the volcano. The station is located at Daang Kastila, at the northern portion of the main crater rim. It measures hourly the diffuse CO2 efflux, atmospheric CO2 concentration, soil water content and temperature, wind speed and direction, air temperature and humidity, rainfall

  8. Monitoring the mesospheric CO2 ice clouds by OMEGA/MEx

    NASA Astrophysics Data System (ADS)

    Gondet, B.; Bibring, J. P.; Vincendon, M.

    2012-04-01

    Along four consecutive Martian years, we have discovered and systematically monitored the appearance of CO2 ice clouds, mapping large areas in latitude, longitude and date. These observations have been made from large (at apoapsis) to close (at pericenter) distances, thus with varying resolutions. We have identified the proper locations, altitude and seasons of these clouds. During the past year, we have observed a temporal shift in the occurrence of the clouds, preceded by the evolution of dust clouds, possibly acting as nucleation site for the CO2 clouds. We shall present these new results, and discuss them in the framework of cloud formation processes.

  9. Electromagnetic monitoring of CO2 dissemination: a case study in the North Eastern German Basin

    NASA Astrophysics Data System (ADS)

    Muñoz, G.; Ritter, O.

    2012-04-01

    Storage of CO2 in saline aquifers is a topic which is recently gaining a lot of interest. The BRINE project, funded by the German Ministry of Education and Research (BMBF) has the double objective of investigating the endangerment of freshwater reservoirs by upward migration of brine from saline aquifers as a result of the pressure increase subsequent to a CO2 injection into a target storage formation and the synergetic utilization of geothermal heat production and CO2 storage by implementation of pressure discharge wells. The success of geological CO2 storage projects depends largely on the ability to monitor the state of the reservoir during and after CO2 injection, particularly in terms of fluid saturation and pressure. This is essential from the reservoir engineering as well as for risk assessment perspectives. Electrical conductivity of sedimentary rocks depends strongly on the presence of fluids, their temperature and salinity. Therefore, electromagnetic (EM) methods, such as magnetotellurics (MT) and controlled source magnetotellurics (CSMT) are promising exploration techniques for characterizing and monitoring deep aquifer systems, such as CO2 storage sites or geothermal reservoirs. In order to develop an electromagnetic monitoring system it is necessary to have a good understanding of the electrical conductivity distribution and the changes produced by the dissemination of the CO2 in the deep saline aquifer. Based on the geological model of the study area and using conductivity values of similar structures in the North Eastern German Basin we have created a vast collection of models simulating different scenarios of CO2 migration, whose responses have been then computed using different forward modelling codes. The synthetic model responses have been calculated both for passive MT (with natural source) and CSMT (with active sources), in 1D, 2D and 3D scenarios. These synthetic model studies represent the basis for the development of a monitoring concept

  10. Stability aspects of a fiber optic sensor for CO2 phase monitoring

    NASA Astrophysics Data System (ADS)

    Prada, Dario; Martelli, Cicero; Gouvêa, Paula M. P.; Kato, Carla C.; Braga, Arthur M. B.; Gomes, Marcos S. P.

    2015-09-01

    In this paper we discuss the stability and effectiveness of an optical fiber sensor for CO2 phase monitoring that could be used inside pipelines, rock caverns and steel tanks for Carbon Capture and Storage (CCS) systems; in Enhanced Oil Recovery (EOR) processes; and in mapping of natural reservoirs. The sensor is an optical fiber refractometer and is shown to be capable of identifying phase changes and when two-phase systems co-exist, even near the phase transition line. When properly calibrated, the sensor can be used to obtain the refractive index and density (calculated with the Lorentz-Lorentz formula) of CO2.

  11. On the development of a methodology for extensive in-situ and continuous atmospheric CO2 monitoring

    NASA Astrophysics Data System (ADS)

    Wang, K.; Chang, S.; Jhang, T.

    2010-12-01

    Carbon dioxide is recognized as the dominating greenhouse gas contributing to anthropogenic global warming. Stringent controls on carbon dioxide emissions are viewed as necessary steps in controlling atmospheric carbon dioxide concentrations. From the view point of policy making, regulation of carbon dioxide emissions and its monitoring are keys to the success of stringent controls on carbon dioxide emissions. Especially, extensive atmospheric CO2 monitoring is a crucial step to ensure that CO2 emission control strategies are closely followed. In this work we develop a methodology that enables reliable and accurate in-situ and continuous atmospheric CO2 monitoring for policy making. The methodology comprises the use of gas filter correlation (GFC) instrument for in-situ CO2 monitoring, the use of CO2 working standards accompanying the continuous measurements, and the use of NOAA WMO CO2 standard gases for calibrating the working standards. The use of GFC instruments enables 1-second data sampling frequency with the interference of water vapor removed from added dryer. The CO2 measurements are conducted in the following timed and cycled manner: zero CO2 measurement, two standard CO2 gases measurements, and ambient air measurements. The standard CO2 gases are calibrated again NOAA WMO CO2 standards. The methodology is used in indoor CO2 measurements in a commercial office (about 120 people working inside), ambient CO2 measurements, and installed in a fleet of in-service commercial cargo ships for monitoring CO2 over global marine boundary layer. These measurements demonstrate our method is reliable, accurate, and traceable to NOAA WMO CO2 standards. The portability of the instrument and the working standards make the method readily applied for large-scale and extensive CO2 measurements.

  12. 40 CFR 600.208-12 - Calculation of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related exhaust...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... or diesel test fuel. (ii) Calculate the city, highway, and combined fuel economy, CO2 emissions, and...-based fuel economy, CO2 emissions, and carbon-related exhaust emissions for a model type. 600.208-12... FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Procedures for Calculating...

  13. 40 CFR 600.208-12 - Calculation of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related exhaust...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... or diesel test fuel. (ii) Calculate the city, highway, and combined fuel economy, CO2 emissions, and...-based fuel economy, CO2 emissions, and carbon-related exhaust emissions for a model type. 600.208-12... FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Procedures for Calculating...

  14. 40 CFR 600.209-12 - Calculation of vehicle-specific 5-cycle fuel economy and CO2 emission values for a model type.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... basic engine (i.e., they are not included in the calculation of the original base level fuel economy... highway fuel economy and CO2 emission values from the tests performed using gasoline or diesel test fuel... economy and CO2 emission values from the tests performed using gasoline or diesel test fuel....

  15. 40 CFR 600.208-12 - Calculation of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related exhaust...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... or diesel test fuel. (ii) Calculate the city, highway, and combined fuel economy, CO2 emissions, and...-based fuel economy, CO2 emissions, and carbon-related exhaust emissions for a model type. 600.208-12... FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Procedures for Calculating...

  16. 40 CFR 600.209-12 - Calculation of vehicle-specific 5-cycle fuel economy and CO2 emission values for a model type.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... basic engine (i.e., they are not included in the calculation of the original base level fuel economy... highway fuel economy and CO2 emission values from the tests performed using gasoline or diesel test fuel... economy and CO2 emission values from the tests performed using gasoline or diesel test fuel....

  17. Toward Regional Fossil Fuel CO2 Emissions Verification Using WRF-CHEM

    NASA Astrophysics Data System (ADS)

    Delle Monache, L.; Kosoviæ, B.; Cameron-Smith, P.; Bergmann, D.; Grant, K.; Guilderson, T.

    2008-12-01

    As efforts to reduce emissions of green house gases take shape it is becoming obvious that an essential component of a viable solution will involve emission verification. While detailed inventories of green house gas sources will represent important component of the solution additional verification methodologies will be necessary to reduce uncertainties in emission estimates especially for distributed sources and CO2 offsets. We developed tools for solving inverse dispersion problem for distributed emissions of green house gases. For that purpose we combine probabilistic inverse methodology based on Bayesian inversion with stochastic sampling and weather forecasting and air quality model WRF-CHEM. We demonstrate estimation of CO2 emissions associated with fossil fuel burning in California over two one-week periods in 2006. We use WRF- CHEM in tracer simulation mode to solve forward dispersion problem for emissions over eleven air basins. We first use direct inversion approach to determine optimal location for a limited number of CO2 - C14 isotope sensors. We then use Bayesian inference with stochastic sampling to determine probability distributions for emissions from California air basins. Moreover, we vary the number of sensors and frequency of measurements to study their effect on the accuracy and uncertainty level of the emission estimation. Finally, to take into account uncertainties associated with forward modeling, we combine Bayesian inference and stochastic sampling with ensemble modeling. The ensemble is created by running WRF-CHEM with different initial and boundary conditions as well as different boundary layer and surface model options. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory (LLNL) under Contract DE-AC52-07NA27344 (LLNL-ABS-406901-DRAFT). The project 07-ERD- 064 was funded by the Laboratory Directed Research and Development Program at LLNL.

  18. Investigating the Feasibility of Traveltime Tomography for Monitoring CO2 Enhanced Oil Recovery

    NASA Astrophysics Data System (ADS)

    Barghouty, L. K.; Quan, Y.; Harris, J. M.

    2012-12-01

    CO2 Enhanced Oil Recovery (EOR) is a process for improving the recovery of oil from a reservoir through injection of carbon dioxide. The monitoring CO2 EOR requires an effective method that detects the location of injected CO2 in the reservoir. This project investigates the feasibility of using crosswell seismic tomography to monitor the distribution of injected CO2. Tomography converts seismic traveltime data into seismic velocity models. The effectiveness of seismic tomography as a monitoring method depends on the level of its repeatability, e.g., how accurate the results will be under possible survey challenges such as incomplete datasets and errors in survey geometry. These challenges are found in the seismic data in a field test from west Texas. Using synthetic data comprising pre-injection and post-injection datasets similar to the recorded field datasets, several data processing techniques have been tested to assess the difference between the pre-injection and post-injection velocity models, to determine how data processing affects the time-lapse results. Such tests include limiting the aperture of one or both surveys, eliminating near offset data where traveltime picks are difficult to make, shifting receivers/sources depth coordinates to simulate the survey acquisition errors, and patching (data extrapolation) to correct for missing data. Synthetic results show that near-offset elimination does not notably affect the quality of the time-lapse results while matching pre- and post-injection survey geometries gives better results even for incomplete survey geometries. Patching of incomplete datasets gives reasonable results within certain limits, and having a depth error more than twice the inversion grid size significantly affects the results. Based on synthetic results, repeatability of seismic tomography depends highly on the accuracy of source and receiver coordinates, while repeatability tolerates mismatching pre-injection and post-injection survey

  19. Optimal distribution of borehole geophones for monitoring CO2-injection-induced seismicity

    NASA Astrophysics Data System (ADS)

    Huang, L.; Chen, T.; Foxall, W.; Wagoner, J. L.

    2016-12-01

    The U.S. DOE initiative, National Risk Assessment Partnership (NRAP), aims to develop quantitative risk assessment methodologies for carbon capture, utilization and storage (CCUS). As part of tasks of the Strategic Monitoring Group of NRAP, we develop a tool for optimal design of a borehole geophones distribution for monitoring CO2-injection-induced seismicity. The tool consists of a number of steps, including building a geophysical model for a given CO2 injection site, defining target monitoring regions within CO2-injection/migration zones, generating synthetic seismic data, giving acceptable uncertainties in input data, and determining the optimal distribution of borehole geophones. We use a synthetic geophysical model as an example to demonstrate the capability our new tool to design an optimal/cost-effective passive seismic monitoring network using borehole geophones. The model is built based on the geologic features found at the Kimberlina CCUS pilot site located in southern San Joaquin Valley, California. This tool can provide CCUS operators with a guideline for cost-effective microseismic monitoring of geologic carbon storage and utilization.

  20. 1. Fourteen Years Of Diffuse CO2 Monitoring At Cerro Negro Volcano, Nicaragua

    NASA Astrophysics Data System (ADS)

    Barrancos Martinez, Jose; Melián, Gladys; Ibarra, Martha; Álvarez, Julio; Rodríguez, Fátima; Nolasco, Dácil; Padilla, Germán; Calvo, David; Dionis, Samara; Padrón, Eleazar; Hernández, Iñigo; Hernández, Pedro A.; Pérez, Nemesio M.; Muñoz, Angélica

    2013-04-01

    7. Cerro Negro is an active basaltic volcano belonging to the active Central American Volcanic Belt, which includes a 1,100 Km long chain of 41 active volcanoes from Guatemala to Panama. Cerro Negro first erupted in 1850 and has experienced 21 eruptive eruptions with inter eruptive average periods between 7 and 9 years. Since the last eruption occurred on 5 August 1999, with erupted lava flows and ash clouds together with gas emissions, a collaborative research program between INETER and ITER was established for monitoring diffuse CO2 emissions from this volcano. Until 2012, twelve soil CO2 emission surveys covering an area of 0,6 km2 have been performed by means of the accumulation chamber method to evaluate the spatial and temporal variations of CO2 degassing rate in relation to the eruptive cycle of Cerro Negro. A total diffuse CO2 emission output of 1,869 t•d-1 was estimated for the 1999 survey; just 3 months after the 1999 eruption which can be considered within the post-eruptive phase. For the April, 2002 and March, 2008 surveys, considered within the inter-eruptive phase, a clear decreasing tendency on the total diffuse CO2 output was observed, with estimates of 431 and 10 t•d-1, respectively, except a small increment in 2004, to 256 t d-1, associated with an anomalous seismic activity. The higher anomalies are located around the crater of 1995 and 1999. An increasing on the total CO2 emission has been observed, from December 2008 to February 2011, with total diffuse CO2 output estimates from 12 t•d-1 to 43 t•d-1, respectively. These temporal variations show a close relationship between diffuse CO2 emission and the eruptive cycle at Cerro Negro. This relationship indicates that monitoring CO2 emission is an important geochemical tool for the volcanic surveillance at Cerro Negro. References: (1) Rodríguez et al. (2009) AGU Fall Meeting 2009. EOS, AGU,V21-2017 . (2) Padilla et al. (2008). IV Reunión de la Red Española de Volcanología, Almagro 2008

  1. Monitoring CO2 emissions to gain a dynamic view of carbon allocation to arbuscular mycorrhizal fungi.

    PubMed

    Slavíková, Renata; Püschel, David; Janoušková, Martina; Hujslová, Martina; Konvalinková, Tereza; Gryndlerová, Hana; Gryndler, Milan; Weiser, Martin; Jansa, Jan

    2017-01-01

    Quantification of carbon (C) fluxes in mycorrhizal plants is one of the important yet little explored tasks of mycorrhizal physiology and ecology. (13)CO2 pulse-chase labelling experiments are increasingly being used to track the fate of C in these plant-microbial symbioses. Nevertheless, continuous monitoring of both the below- and aboveground CO2 emissions remains a challenge, although it is necessary to establish the full C budget of mycorrhizal plants. Here, a novel CO2 collection system is presented which allows assessment of gaseous CO2 emissions (including isotopic composition of their C) from both belowground and shoot compartments. This system then is used to quantify the allocation of recently fixed C in mycorrhizal versus nonmycorrhizal Medicago truncatula plants with comparable biomass and mineral nutrition. Using this system, we confirmed substantially greater belowground C drain in mycorrhizal versus nonmycorrhizal plants, with the belowground CO2 emissions showing large variation because of fluctuating environmental conditions in the glasshouse. Based on the assembled (13)C budget, the C allocation to the mycorrhizal fungus was between 2.3% (increased (13)C allocation to mycorrhizal substrate) and 2.9% (reduction of (13)C allocation to mycorrhizal shoots) of the plant gross photosynthetic production. Although the C allocation to shoot respiration (measured during one night only) did not differ between the mycorrhizal and nonmycorrhizal plants under our experimental conditions, it presented a substantial part (∼10%) of the plant C budget, comparable to the amount of CO2 released belowground. These results advocate quantification of both above- and belowground CO2 emissions in future studies.

  2. Gas monitoring during the CO2 back production field test at the Ketzin pilot site

    NASA Astrophysics Data System (ADS)

    Szizybalski, Alexandra; Zimmer, Martin; Kujawa, Christian; Erzinger, Jörg

    2015-04-01

    fluids before the injection of CO2 showed that CH4, CO2, H2 and N2 are present in the original formation fluid (0.17 mg/l, 0.08 mg/l, 0.14 mg/l, 17.9 mg/l fluid; Morozova et al., 2010). The observed N2 concentrations in the back-produced gas may, therefore, result from the field tests and from injection management or from the original formation fluid. Results of the isotopic measurements are in preparation. Morozova, D., Wandrey, M., Alawi, M., Zimmer, M., Vieth, A., Zettlitzer, M., Wuerdemann, H. (2010): Monitoring of the microbial community composition in saline aquifers during CO2 storage by fluorescence in situ hybridisation. International Journal of Greenhouse Gas Control, Volume 4, Pages 981-989. doi:10.1016/j.ijggc.2009.11.014.

  3. CO2FieldLab project. Near-surface downhole electrical resistivity monitoring for CO2 shallow injection at the Svelvik ridge (Norway).

    NASA Astrophysics Data System (ADS)

    Denchik, N.; Pezard, P.; Paris, J.; Geeraert, M.; Henry, G.; Baqué, L.; Barry, S.; Neyens, D.

    2012-04-01

    The CO2FieldLab shallow injection experiment is a collaborative effort aimed at developing, verifying, and evaluating near-surface monitoring techniques for geological sequestration of CO2. The objective is to create a downhole leakage of CO2 in order to demonstrate whether existing monitoring techniques have the ability to detect and quantify the CO2 loss. The CO2FieldLab project associates collaboration from several research groups and organizations (SINTEF, NGI, BRGM, BGS, CNRS, imaGeau and Schlumberger). For this, the field Laboratory for monitoring CO2 migration and leakage was established in Holocene deposits of the Svelvik ridge, located in the Drammensfjord 50 km south of Oslo (Norway). It is a glaciofluvial-glaciomarine terminal deposit formed during the last deglaciation. The depth to the bedrock is located between 300 and 400 m. The central part of the ridge is aerially exposed up to 70 m above sea level, constituting a phreatic aquifer. The characterization phase and associated modelling suggest that the site is suitable for studying both gas migration and leakage at shallow depths. The shallow aquifer (down to 50 m) consists in a relatively homogeneous sand body with a depositional dip of about 10° to the North. The shallow injection experiment took place in September of 2011 and consisted in an injection of CO2 at a depth of 20 m from a 45° inclined well. The purpose of this phase was to simulate a point source leakage, which could possibly occur due to failure of a deep well completion. A total mass of 1.67 ton of CO2 was injected over a period of 6 days. The water table was located at 60 cm depth during the experiment and a transition from fresh to salt pore water was found below 12 m depth. An integrated set of surface and downhole strategies was deployed across a 64 m2 square monitoring area: cross-hole radar, water and gas phases physico-chemical parameters (BRGM); multi-hole electrical ALERT system (BGS), CO2 concentration in soils and gas

  4. A rate-based transcutaneous CO2 sensor for noninvasive respiration monitoring.

    PubMed

    Chatterjee, M; Ge, X; Kostov, Y; Luu, P; Tolosa, L; Woo, H; Viscardi, R; Falk, S; Potts, R; Rao, G

    2015-05-01

    The pain and risk of infection associated with invasive blood sampling for blood gas measurements necessitate the search for reliable noninvasive techniques. In this work we developed a novel rate-based noninvasive method for a safe and fast assessment of respiratory status. A small sampler was built to collect the gases diffusing out of the skin. It was connected to a CO2 sensor through gas-impermeable tubing. During a measurement, the CO2 initially present in the sampler was first removed by purging it with nitrogen. The gases in the system were then recirculated between the sampler and the CO2 sensor, and the CO2 diffusion rate into the sampler was measured. Because the measurement is based on the initial transcutaneous diffusion rate, reaching mass transfer equilibrium and heating the skin is no longer required, thus, making it much faster and safer than traditional method. A series of designed experiments were performed to analyze the effect of the measurement parameters such as sampler size, measurement location, subject positions, and movement. After the factor analysis tests, the prototype was sent to a level IV NICU for clinical trial. The results show that the measured initial rate of increase in CO2 partial pressure is linearly correlated with the corresponding arterial blood gas measurements. The new approach can be used as a trending tool, making frequent blood sampling unnecessary for respiratory status monitoring.

  5. Monitoring CO2 sources and sinks from space : the Orbiting Carbon Observatory (OCO) Mission

    NASA Technical Reports Server (NTRS)

    Crisp, David

    2006-01-01

    NASA's Orbiting Carbon Observatory (OCO) will make the first space-based measurements of atmospheric carbon dioxide (CO2) with the precision, resolution, and coverage needed to characterize the geographic distribution of CO2 sources and sinks and quantify their variability over the seasonal cycle. OCO is currently scheduled for launch in 2008. The observatory will carry a single instrument that incorporates three high-resolution grating spectrometers designed to measure the near-infrared absorption by CO2 and molecular oxygen (O2) in reflected sunlight. OCO will fly 12 minutes ahead of the EOS Aqua platform in the Earth Observing System (EOS) Afternoon Constellation (A-Train). The in-strument will collect 12 to 24 soundings per second as the Observatory moves along its orbit track on the day side of the Earth. A small sampling footprint (<3 km2 at nadir) was adopted to reduce biases in each sounding associated with clouds and aerosols and spatial variations in surface topography. A comprehensive ground-based validation program will be used to assess random errors and biases in the XCO2 product on regional to continental scales. Measurements collected by OCO will be assimilated with other environmental measurements to retrieve surface sources and sinks of CO2. This information could play an important role in monitoring the integrity of large scale CO2 sequestration projects.

  6. Effective detection of CO2 leakage: a comparison of groundwater sampling and pressure monitoring

    DOE PAGES

    Keating, Elizabeth; Dai, Zhenxue; Dempsey, David; ...

    2014-12-31

    Shallow aquifer monitoring is likely to be a required aspect to any geologic CO2 sequestration operation. Collecting groundwater samples and analyzing for geochemical parameters such as pH, alkalinity, total dissolved carbon, and trace metals has been suggested by a number of authors as a possible strategy to detect CO2 leakage. The effectiveness of this approach, however, will depend on the hydrodynamics of the leak-induced CO2 plume and the spatial distribution of the monitoring wells relative to the origin of the leak. To our knowledge, the expected effectiveness of groundwater sampling to detect CO2 leakage has not yet been quantitatively assessed.more » In this study we query hundreds of simulations developed for the National Risk Assessment Project (US DOE) to estimate risks to drinking water resources associated with CO2 leaks. The ensemble of simulations represent transient, 3-D multi-phase reactive transport of CO2 and brine leaked from a sequestration reservoir, via a leaky wellbore, into an unconfined aquifer. Key characteristics of the aquifer, including thickness, mean permeability, background hydraulic gradient, and geostatistical measures of aquifer heterogeneity, were all considered uncertain parameters. Complex temporally-varying CO2 and brine leak rate scenarios were simulated using a heuristic scheme with ten uncertain parameters. The simulations collectively predict the spatial and temporal evolution of CO2 and brine plumes over 200 years in a shallow aquifer under a wide range of leakage scenarios and aquifer characteristics. Using spatial data from an existing network of shallow drinking water wells in the Edwards Aquifer, TX, as one illustrative example, we calculated the likelihood of leakage detection by groundwater sampling. In this monitoring example, there are 128 wells available for sampling, with a density of about 2.6 wells per square kilometer. If the location of the leak is unknown a priori, a reasonable assumption in many cases

  7. Understanding of Electrochemical Mechanisms for CO2 Capture and Conversion into Hydrocarbon Fuels in Transition-Metal Carbides (MXenes).

    PubMed

    Li, Neng; Chen, Xingzhu; Ong, Wee-Jun; MacFarlane, Douglas R; Zhao, Xiujian; Cheetham, Anthony K; Sun, Chenghua

    2017-09-13

    Two-dimensional (2D) transition-metal (groups IV, V, VI) carbides (MXenes) with formulas M3C2 have been investigated as CO2 conversion catalysts with well-resolved density functional theory calculations. While MXenes from the group IV to VI series have demonstrated an active behavior for the capture of CO2, the Cr3C2 and Mo3C2 MXenes exhibit the most promising CO2 to CH4 selective conversion capabilities. Our results predicted the formation of OCHO(•) and HOCO(•) radical species in the early hydrogenation steps through spontaneous reactions. This provides atomic level insights into the computer-aided screening for high-performance catalysts and the understanding of electrochemical mechanisms for CO2 reduction to energy-rich hydrocarbon fuels, which is of fundamental significance to elucidate the elementary steps for CO2 fixation.

  8. Integrated Geophysical Monitoring Program to Study Flood Performance and Incidental CO2 Storage Associated with a CO2 EOR Project in the Bell Creek Oil Field

    NASA Astrophysics Data System (ADS)

    Burnison, S. A.; Ditty, P.; Gorecki, C. D.; Hamling, J. A.; Steadman, E. N.; Harju, J. A.

    2013-12-01

    The Plains CO2 Reduction (PCOR) Partnership, led by the Energy & Environmental Research Center, is working with Denbury Onshore LLC to determine the effect of a large-scale injection of carbon dioxide (CO2) into a deep clastic reservoir for the purpose of simultaneous CO2 enhanced oil recovery (EOR) and to study incidental CO2 storage at the Bell Creek oil field located in southeastern Montana. This project will reduce CO2 emissions by more than 1 million tons a year while simultaneously recovering an anticipated 30 million barrels of incremental oil. The Bell Creek project provides a unique opportunity to use and evaluate a comprehensive suite of technologies for monitoring, verification, and accounting (MVA) of CO2 on a large-scale. The plan incorporates multiple geophysical technologies in the presence of complementary and sometimes overlapping data to create a comprehensive data set that will facilitate evaluation and comparison. The MVA plan has been divided into shallow and deep subsurface monitoring. The deep subsurface monitoring plan includes 4-D surface seismic, time-lapse 3-D vertical seismic profile (VSP) surveys incorporating a permanent borehole array, and baseline and subsequent carbon-oxygen logging and other well-based measurements. The goal is to track the movement of CO2 in the reservoir, evaluate the recovery/storage efficiency of the CO2 EOR program, identify fluid migration pathways, and determine the ultimate fate of injected CO2. CO2 injection at Bell Creek began in late May 2013. Prior to injection, a monitoring and characterization well near the field center was drilled and outfitted with a distributed temperature-monitoring system and three down-hole pressure gauges to provide continuous real-time data of the reservoir and overlying strata. The monitoring well allows on-demand access for time-lapse well-based measurements and borehole seismic instrumentation. A 50-level permanent borehole array of 3-component geophones was installed in a

  9. Monitoring Surface CO2 Leaks Using Hyperspectral Plant Signatures During the 2008 and 2009 ZERT Shallow Subsurface CO2 Release Experiment in Bozeman, MT

    NASA Astrophysics Data System (ADS)

    Male, E. J.; Pickles, W.; Silver, E. A.; Hoffmann, G. D.; Lewicki, J. L.; Apple, M. E.; Repasky, K. S.; Dobeck, L.; Burton, E. A.

    2009-12-01

    Hyperspectral plant signatures can be a powerful tool in the monitoring, verification, and accounting (MVA) of geologic carbon sequestration fields. They can be used to ensure safe and effective sequestration of carbon on short term, as well as on long term timescales. A compromised sequestration field could release CO2 to the surface, where it can negatively impact overlying vegetation. Plant stress caused by a CO2 leak can be observed as changes in the visible to near-infrared reflectance spectra of vegetation. We tested this technique during two controlled shallow CO2 injections during the summers of 2008 and 2009, with each injection lasting for approximately 4 weeks. CO2 gas was released through a 100-meter long horizontal injection well, at a flow rate of 300 kg/day in 2008, and 200 kg/day in 2009. In both years, overlying vegetation comprised various short and tall grasses, alfalfa, and dandelions. During the spring of 2009, following the 2008 experiment, a species of short grass, Kentucky Bluegrass (Poa pratensis), grew predominately in areas where high CO2 fluxes were previously measured, suggesting long term changes to the site as a result of the CO2 leaks. We used a “FieldSpec Pro” spectrometer by Analytical Spectral Devices (ASD, Inc.) to monitor plant health by measuring spectral signatures nearly daily for both experiments. We measured plants located directly over the injection well to10 m away from the well. Acquiring data both inside and outside of the CO2 leak zones allowed us to normalize our measurements to seasonal changes and other environmental factors that affected the vegetation. In both the 2008 and 2009 experiments, we began to observe plant stress within approximately 4 days of the start of each injection. The measured plant stress each year was located within zones of high CO2 flux from the injections. This correlation was also seen in aerial hyperspectral imagery acquired in 2008 by Resonon Inc. of Bozeman, MT using their self

  10. CO2 Fluxes Monitoring at the Level of Field Agroecosystem in Moscow Region of Russia

    NASA Astrophysics Data System (ADS)

    Meshalkina, Joulia; Mazirov, Ilya; Samardzic, Miljan; Yaroslavtsev, Alexis; Valentini, Riccardo; Vasenev, Ivan

    2014-05-01

    The Central Russia is still one of the less GHG-investigated European areas especially in case of agroecosystem-level carbon dioxide fluxes monitoring by eddy covariance method. The eddy covariance technique is a statistical method to measure and calculate vertical turbulent fluxes within atmospheric boundary layers. The major assumption of the metod is that measurements at a point can represent an entire upwind area. Eddy covariance researches, which could be considered as repeated for the same area, are very rare. The research has been carried out on the Precision Farming Experimental Field of the Russian Timiryazev State Agricultural University (Moscow, Russia) in 2013 under the support of RF Government grant No. 11.G34.31.0079. Arable derno-podzoluvisls have around 1 The results have shown high daily and seasonal dynamic of agroecosystem CO2 emission. Sowing activates soil microbiological activity and the average soil CO2 emission and adsorption are rising at the same time. CO2 streams are intensified after crop emerging from values of 3 to 7 μmol/s-m2 for emission, and from values of 5 to 20 μmol/s-m2 for adsorption. Stabilization of the flow has come at achieving plants height of 10-12 cm. The vegetation period is characterized by high average soil CO2 emission and adsorption at the same time, but the adsorption is significantly higher. The resulted CO2 absorption during the day is approximately 2-5 times higher than emissions at night. For example, in mid-June, the absorption value was about 0.45 mol/m2 during the day-time, and the emission value was about 0.1 mol/m2 at night. After harvesting CO2 emission is becoming essentially higher than adsorption. Autumn and winter data are fluctuate around zero, but for some periods a small predominance of CO2 emissions over the absorption may be observed. The daily dynamics of CO2 emissions depends on the air temperature with the correlation coefficient changes between 0.4 and 0.8. Crop stage, agrotechnological

  11. On the feasibility of borehole-to-surface electromagnetics for monitoring CO2 sequestration

    NASA Astrophysics Data System (ADS)

    Wilson, G. A.; Zhdanov, M. S.; Hibbs, A. D.; Black, N.; Gribenko, A. V.; Cuma, M.; Agundes, A.; Eiskamp, G.

    2012-12-01

    Carbon capture and storage (CCS) projects rely on storing supercritical CO2 in deep saline reservoirs where buoyancy forces drive the injected CO2 upward into the aquifer until a seal is reached. The permanence of the sequestration depends entirely on the long-term geological integrity of the seal. Active geophysical monitoring of the sequestration is critical for informing CO2 monitoring, accounting and verification (MVA) decisions. During injection, there exists a correlation between the changes in CO2 and water saturations in a saline reservoir. Dissolved salts react with the CO2 to precipitate out as carbonates, thereby generally decreasing the electrical resistivity. As a result, there is a correlation between the change in fluid saturation and measured electromagnetic (EM) fields. The challenge is to design an EM survey appropriate for monitoring large, deep reservoirs. Borehole-to-surface electromagnetic (BSEM) surveys consist of borehole-deployed galvanic transmitters and a surface-based array of electric and magnetic field sensors. During a recent field trial, it was demonstrated that BSEM could successfully identify the oil-water contact in the water-injection zone of a carbonate reservoir. We review the BSEM methodology, and perform full-field BSEM modeling. The 3D resistivity models used in this study are based on dynamic reservoir simulations of CO2 injection into a saline reservoir. Although the electric field response at the earth's surface is low, we demonstrate that it can be accurately measured and processed with novel methods of noise cancellation and sufficient stacking over the period of monitoring to increase the signal-to-noise ratio for subsequent seismic- and well-constrained 3D inversion. For long-term or permanent monitoring, we discuss the deployment of novel electric field sensors with chemically inert electrodes that couple to earth in a capacitive manner. This capacitive coupling is a purely EM phenomenon, which, to first order, has

  12. Passive microseismic monitoring at an Australian CO2 geological storage site

    NASA Astrophysics Data System (ADS)

    Siggins, Anthony

    2010-05-01

    Passive microseismic monitoring at an Australian CO2 geological storage site A.F. Siggins1 and T. Daley2 1. CO2CRC at CSIRO Earth Science and Resource Engineering, Clayton, Victoria, Australia 2. Lawrence Berkeley National Labs, Berkeley, CA, USA Prior to the injection of CO2, background micro-seismic (MS) monitoring commenced at the CO2CRC Otway project site in Victoria, south-eastern Australia on the 4th of October 2007. The seismometer installation consisted of a solar powered ISS MS™ seismometer connected to two triaxial geophones placed in a gravel pack in a shallow borehole at 10m and 40 m depth respectively. The seismometer unit was interfaced to a digital radio which communicated with a remote computer containing the seismic data base. This system was designed to give a qualitative indication of any natural micro-seismicity at the site and to provide backup to a more extensive geophone array installed at the reservoir depth of approximately 2000m. During the period, October to December 2007 in excess of 150 two-station events were recorded. These events could all be associated with surface engineering activities during the down-hole installation of instruments at the nearby Naylor 1 monitoring well and surface seismic weight drop investigations on site. Source location showed the great majority of events to be clustered on the surface. MS activity then quietened down with the completion of these tasks. Injection of a CO2 rich gas commenced in mid March 2008 continuing until late August 2009 with approximately 65,000 tonnes being injected at 2050m depth in to a depleted natural gas formation. Only a small number of subsurface MS events were recorded during 2008 although the monitoring system suffered from long periods of down-time due to power supply failures and frequent mains power outages in the region. In March 2009 the surface installation was upgraded with new hardware and software. The seismometer was replaced with a more sensitive ISS 32-bit GS

  13. Solar-to-chemical and solar-to-fuel production from CO2 by metabolically engineered microorganisms.

    PubMed

    Woo, Han Min

    2017-01-11

    Recent development of carbon capture utilization (CCU) for reduction of greenhouse gas emission are reviewed. In the case of CO2 utilization, I describe development of solar-to-chemical and solar-to-fuel technology that refers to the use of solar energy to convert CO2 to desired chemicals and fuels. Photoautotrophic cyanobacterial platforms have been extensively developed on this principle, producing a diverse range of alcohols, organic acids, and isoprenoids directly from CO2. Recent breakthroughs in the metabolic engineering of cyanobacteria were reviewed. In addition, adoption of the light harvesting mechanisms from nature, photovoltaics-derived water splitting technologies have recently been integrated with microbial biotechnology to produce desired chemicals. Studies on the integration of electrode material with next-generation microbes are showcased for alternative solar-to-chemical and solar-to-fuel platforms.

  14. Rapid, Long-term Monitoring of CO2 Concentration and δ13CO2 at CCUS Sites Allows Discrimination of Leakage Patterns from Natural Background Values

    NASA Astrophysics Data System (ADS)

    Galfond, B.; Riemer, D. D.; Swart, P. K.

    2014-12-01

    In order for Carbon Capture Utilization and Storage (CCUS) to gain wide acceptance as a method for mitigating atmospheric CO2 concentrations, schemes must be devised to ensure that potential leakage is detected. New regulations from the US Environmental Protection Agency require monitoring and accounting for Class VI injection wells, which will remain a barrier to wide scale CCUS deployment until effective and efficient monitoring techniques have been developed and proven. Monitoring near-surface CO2 at injection sites to ensure safety and operational success requires high temporal resolution CO2 concentration and carbon isotopic (δ13C) measurements. The only technologies currently capable of this rapid measurement of δ13C are optical techniques such as Cavity Ringdown Spectroscopy (CRDS). We have developed a comprehensive remote monitoring approach using CRDS and a custom manifold system to obtain accurate rapid measurements from a large sample area over an extended study period. Our modified Picarro G1101-i CRDS allows for automated rapid and continuous field measurement of δ13CO2 and concentrations of relevant gas species. At our field site, where preparations have been underway for Enhanced Oil Recovery (EOR) operations, we have been able to measure biogenic effects on a diurnal scale, as well as variation due to precipitation and seasonality. Taking these background trends into account, our statistical treatment of real data has been used to improve signal-to-noise ratios by an order of magnitude over published models. Our system has proven field readiness for the monitoring of sites with even modest CO2 fluxes.

  15. The electrical conductivity of CO2-bearing pore waters at elevated pressure and temperature: a laboratory study and its implications in CO2 storage monitoring and leakage detection

    NASA Astrophysics Data System (ADS)

    Börner, Jana H.; Herdegen, Volker; Repke, Jens-Uwe; Spitzer, Klaus

    2015-11-01

    and ion species dependence of the CO2 effect. Furthermore, the observations are analysed and predicted with a semi-analytical formulation for the electrical pore water conductivity taking into account the species' interactions. For the applicability of our results in practice of exploration and monitoring, we additionally provide a purely empirical formulation to compute the impact of CO2 on pore water conductivity at equilibrium which only requires the input of pressure, temperature and salinity information.

  16. Monitoring CO2 Sequestration by Mineral Carbonation in Mine Tailings at Thetford Mines, Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Lechat, K.; Lemieux, J. M.; Molson, J. W. H.; Beaudoin, G.; Hebert, R.

    2014-12-01

    Mineral carbonation is considered a permanent option to capture and store atmospheric CO2. This reaction occurs naturally under ambient conditions in ultramafic mining and milling waste. In the region of Thetford Mines, Quebec, chrysotile mining has produced approximately 0.8 Gt of magnesium-rich milling waste, which mainly consists of poorly sorted ultramafic rock fragments (< 10 cm) and chrysotile fibers. To quantify the amount of CO2 that can be captured in the mine wastes of Thetford Mines, two experimental pilot-scale tailings cells were constructed and instrumented for measuring soil temperature, volumetric water content, gas pressure and gas composition, with ambient conditions recorded by an autonomous meteorological station. The cells were monitored for water geochemistry, carbon content and mineralogy, with the objective to better understand the mineral carbonation processes under natural conditions and to propose a conceptual model for mineral carbonation at the pilot scale. To validate this model, numerical simulations with the MIN3P reactive transport code have been carried out. The chemical composition of the cell leachate (pH > 10, Mg from 85 to 140 mg.L-1, and high total alkalinity from 260 to 300 mg.L-1 CaCO3) is consistent with active CO2 mineralization reactions within the cell. SEM analyses show precipitation of dypingite with a lamellar texture and cemented grain surfaces. The milling waste contains up to 1.2% C, which indicates CO2 sequestration by mineral carbonation. Measured CO2 concentrations in the interstitial air are also ten times lower than in the atmosphere. Analysis of seasonal variations in fluid flow and heat transfer (essentially by thermal conduction) shows that molecular diffusion is the main process for CO2 supply within the experimental cells. These observations have helped develop a conceptual model for mineral carbonation in the wastes and were used to calibrate the reactive transport model.

  17. A new device for continuous monitoring the CO2 dissolved in water

    NASA Astrophysics Data System (ADS)

    de Gregorio, S.; Camarda, M.; Cappuzzo, S.; Giudice, G.; Gurrieri, S.; Longo, M.

    2009-04-01

    The measurements of dissolved CO2 in water are common elements of industrial processes and scientific research. In order to perform gas dissolved measurements is required to separate the dissolved gaseous phase from water. We developed a new device able to separate the gases phase directly in situ and well suitable for continuous measuring the CO2 dissolved in water. The device is made by a probe of a polytetrafluorethylene (PTFE) tube connected to an I.R. spectrophotometer (I.R.) and a pump. The PTFE is a polymeric semi-permeable membrane and allows the permeation of gas in the system. Hence, this part of the device is dipped in water in order to equilibrate the probe headspace with the dissolved gases. The partial pressure of the gas i in the headspace at equilibrium (Pi) follows the Henry's law: Pi=Hi•Ci, where Hi is the Henry's constant and Ci is the dissolved concentration of gas i. After the equilibrium is achieved, the partial pressure of CO2 inside the tube is equal to the partial pressure of dissolved CO2. The concentration of CO2 is measured by the I.R. connected to the tube. The gas is moved from the tube headspace to the I.R. by using the pump. In order to test the device and assess the best operating condition, several experimental were performed in laboratory. All the test were executed in a special apparatus where was feasible to create controlled atmospheres. Afterward the device has been placed in a draining tunnel sited in the Mt. Etna Volcano edifice (Italy). The monitored groundwater intercepts the Pernicana Fault, along which degassing phenomena are often observed. The values recorded by the station result in agreement with monthly directly measurements of dissolved CO2 partial pressure.

  18. Borehole Seismic Monitoring of Injected CO2 at the Frio Site

    NASA Astrophysics Data System (ADS)

    Daley, T. M.; Myer, L.; Hoversten, G. M.; Peterson, J. E.

    2005-12-01

    The recently completed CO2 injection in the brine aquifer of the Frio Formation in southeast Texas provided an opportunity to test borehole seismic monitoring techniques. Designed tests included time-lapse VSP and crosswell surveys which investigated the detectability of CO2 with surface-to-borehole and borehole-to-borehole measurement. The VSP method uses surface seismic sources in conjunction with borehole sensors to measure the seismic properties ( such as velocity and reflection strength) in the vicinity of the borehole. By moving the source location, seismic properties can be mapped spatially around the sensor well. A large change (about 70%)in VSP reflection amplitude from the Frio zone was observed. Because of the relatively small amount of CO2 injected (about 1600 tons), and the thin injection interval (about 6 m thick at 1500 m depth), CO2 detectability by the VSP method was not an assumed certainty. The initial result is therefor quite promising for use of the VSP method. The crosswell method measures wave propagation between wells and can tomographically image the interwell volume. The crosswell survey was conducted using the injection well (for sensors) and a nearby monitoring well (for the source) which is about 30 m offset. Crosswell source locations were centered on the injection interval. The crosswell sensors were also centered on the injection interval, which is the 6-7 m thick, upper C sand in the Frio formation which is at a depth of about 1500 m. Initial analysis of the crosswell data shows good quality P- and S-wave direct arrivals. Time-lapse tomographic imaging maps the changes in velocity (up to 1 km/s) due to the CO2 plume.

  19. Ground gas monitoring: implications for hydraulic fracturing and CO2 storage.

    PubMed

    Teasdale, Christopher J; Hall, Jean A; Martin, John P; Manning, David A C

    2014-12-02

    Understanding the exchange of carbon dioxide (CO2) and methane (CH4) between the geosphere and atmosphere is essential for the management of anthropogenic emissions. Human activities such as carbon capture and storage and hydraulic fracturing ("fracking") affect the natural system and pose risks to future global warming and to human health and safety if not engineered to a high standard. In this paper an innovative approach of expressing ground gas compositions is presented, using data derived from regulatory monitoring of boreholes in the unsaturated zone at infrequent intervals (typically 3 months) with data from a high frequency monitoring instrument deployed over periods of weeks. Similar highly variable trends are observed for time scales ranging from decades to hourly for boreholes located close to sanitary landfill sites. Additionally, high frequency monitoring data confirm the effect of meteorological controls on ground gas emissions; the maximum observed CH4 and CO2 concentrations in a borehole monitored over two weeks were 40.1% v/v and 8.5% v/v respectively, but for 70% of the monitoring period only air was present. There is a clear weakness in current point monitoring strategies that may miss emission events and this needs to be considered along with obtaining baseline data prior to starting any engineering activity.

  20. Microseismic Monitoring of CO2 Sequestration: A Case Study in the Michigan Basin

    NASA Astrophysics Data System (ADS)

    Bohnhoff, M.; Chiaramonte, L.; Zoback, M. D.; Gerst, J.; Gupka, N.

    2008-12-01

    In low permeability hydrocarbon or geothermal reservoirs, passive seismic monitoring of microseismicity induced through fluid-injection is a widely-used method to image fracture growth and permeability enhancement. Currently, similar techniques and approaches are being developed and tested to monitor underground storage of CO2 into different target formations such as saline reservoirs and depleted oil and gas reservoirs. Many saline reservoirs in the mid-continental U.S. appear to have declining porosity and permeability with increasing depth resulting in injectivity and storage challenges. Hence, permeability enhancement (in a manner similar to that used in low permeability hydrocarbon and geothermal reservoirs) may be needed to inject significant volumes of CO2 at acceptable pressures. This analysis is supported by the Global Climate and Energy Project (GCEP) in collaboration with the Midwest Regional Carbon Sequestration Partnership (MRCSP). The Otsego County Test Site in the Michigan Basin was proposed as a demonstration site for CO2 sequestration. A total of more than 10,000 metric tons of supercritical CO2 was injected over a period of 31 days into the target formation (Silurian age Bass Island dolomite -BILD) at 1050 m depth. The injected CO2 was separated from methane produced from the Antrim Shale gas at a nearby site. The injection experiment aimed at evaluating microseismic monitoring technologies and establishing the storage capacity and suitability of the BILD formation. Seismic monitoring of the injection was achieved by two downhole seismometer arrays that consisted of eight, three-component sensors each. The arrays were deployed in two nearby monitoring wells directly above the target horizon at 150 and 550 m lateral distance to the injection point, respectively. The sensor spacing was 15m. Calibration shots in the injection well were used to determine the orientation of the sensors at each depth in the two monitoring wells. The analysis of the

  1. CO2 leakage up from a geological storage site to shallow fresh groundwater: CO2-water-rock interaction assessment and development of sensitive monitoring

    NASA Astrophysics Data System (ADS)

    Humez, Pauline; Audigane, Pascal; Lions, Julie; Négrel, Philippe; Lagneau, Vincent

    2010-05-01

    The assessment of environmental impacts of carbon dioxide storage in geological repository requires the investigation of the potential CO2 leakage back into fresh groundwater, particularly with respect to protected groundwater reserves. We are starting a new project with the aims of developing sensitive monitoring techniques in order to detect potential CO2 leaks and their magnitude as well as their geochemical impacts on the groundwater. In a predictive approach goal, a modelling study of the geochemical impact on fresh groundwaters of a CO2 intrusion during geological storage was performed and serves as a basis for the development of sensitive monitoring techniques (e.g. isotope tracing). Then, isotopic monitoring opportunities will be explored. A modeling study of the geochemical impact on fresh groundwaters of the ingress of CO2 during geological storage was conducted. The 3D model includes (i) storage saline aquifer, (ii) impacted overlying aquifer containing freshwater and (iii) a leakage path way up through an abandoned well represented as 1D porous medium and corresponding to the cement-rock formation interface. This model was used to simulate the supercritical CO2 migration path and the interaction between the fluid and the host rock. The model uses the carbonate saline Dogger aquifer in the Paris Basin as the storage reservoir and the Albian formation (located above the Dogger) as the fresh groundwater aquifer. The principal geochemical process simulated is the acidification of groundwaters due to CO2 dissolution, inducing the dissolution of minerals in the Albian formation. Knowing the mineralogical composition of the impacted aquifer is therefore crucial if we are to correctly determine which elements might be release during the arrival of CO2 in freshwater. Estimates of increases in element concentrations are proposed along with a direct control of the injection procedure. This predictive modeling approach impact of CO2 intrusion to fresh groundwaters

  2. Effect of nanostructured carbon support on copper electrocatalytic activity toward CO2 electroreduction to hydrocarbon fuels

    DOE PAGES

    Baturina, Olga; Lu, Qin; Xu, Feng; ...

    2016-11-10

    The effect of support on electrocatalytic activity of Cu nanoparticles (NPs) towards CO2 electroreduction to hydrocarbon fuels (CH4 and C2H4) is investigated for three types of nanostructured carbons: single wall carbon nanotubes (SWNT), graphene (GP) and onion-like carbon (OLC). Cu/SWNT, Cu/GP and Cu/OLC composite catalysts are synthesized and characterized by X-Ray diffraction analysis, transmission electron microscopy and electrochemical surface area measurements. Electrocatalytic activities of the synthesized materials, as measured in an electrochemical cell connected to a gas chromatograph, are compared to that of Cu NPs supported on Vulcan carbon. All four catalysts demonstrate higher activity towards C2H4 generation vs CH4,more » with production of the latter mostly suppressed on Cu NPs supported on nanostructured substrates. Onset potentials for C2H4 vs CH4 generation are shifted positively by 200 mV for Cu/SWNT, Cu/GP, and Cu/OLC catalysts. The Cu/OLC catalyst is found to be superior to the other two nanostructured catalysts in terms of stability, activity and selectivity towards C2H4 generation. Its faradaic efficiency reached 60% at -1.8 V vs Ag/AgCl. The enhanced activity and stability of Cu/OLC catalyst can be attributed to the unique catalyst design, wherein a shell of OLC surrounds the Cu NPs such that the outer layer acts as a filter that protects the Cu surface from adsorption of undesirable species, enhances its electrocatalytic performance, and improves its viability in CO2 electroreduction reaction.« less

  3. Experimental study on monitoring CO2 sequestration by conjoint analysis of the P-wave velocity and amplitude.

    PubMed

    Chen, Hao; Yang, Shenglai; Huan, Kangning; Li, Fangfang; Huang, Wei; Zheng, Aiai; Zhang, Xing

    2013-09-03

    CO2 sequestration has been considered to be one of the most straightforward carbon management strategies for industrial CO2 emission. Monitoring of the CO2 injection process is one of the best ways to make sure the safety storage but is also a major challenge in CO2 geological sequestration. Previous field and laboratory researches have shown that seismic methods are among the most promising monitoring methods because of the obvious reduction in P-wave velocities caused by CO2 injection. However, as CO2 injection continues, the P-wave velocity becomes increasingly insensitive according to the pilot projects when CO2 saturation is higher than 20-40%. Therefore, the conventional seismic method needs improvement or replacement to solve its limitations. In this study, P-wave velocity and amplitude responses to supercritical CO2 injection in brine-saturated core samples from Jilin oilfield were tested using core displacement and an ultrasonic detection integrated system. Results showed that neither the P-wave velocity nor amplitude could simply be used to monitor the CO2 injection process because of the insensitive or nonmonotonous response. Consequently, a new index was established by synthetically considering these two parameters to invert and monitor the CO2 process, which can be thought of as a newer and more effective assessment criterion for the seismic method.

  4. A simple high-performance matrix-free biomass molten carbonate fuel cell without CO2 recirculation

    PubMed Central

    Lan, Rong; Tao, Shanwen

    2016-01-01

    In previous reports, flowing CO2 at the cathode is essential for either conventional molten carbonate fuel cells (MCFCs) based on molten carbonate/LiAlO2 electrolytes or matrix-free MCFCs. For the first time, we demonstrate a high-performance matrix-free MCFC without CO2 recirculation. At 800°C, power densities of 430 and 410 mW/cm2 are achieved when biomass—bamboo charcoal and wood, respectively–is used as fuel. At 600°C, a stable performance is observed during the measured 90 hours after the initial degradation. In this MCFC, CO2 is produced at the anode when carbon-containing fuels are used. The produced CO2 then dissolves and diffuses to the cathode to react with oxygen in open air, forming the required CO32− or CO42− ions for continuous operation. The dissolved O2− ions may also take part in the cell reactions. This provides a simple new fuel cell technology to directly convert carbon-containing fuels such as carbon and biomass into electricity with high efficiency. PMID:27540588

  5. A simple high-performance matrix-free biomass molten carbonate fuel cell without CO2 recirculation.

    PubMed

    Lan, Rong; Tao, Shanwen

    2016-08-01

    In previous reports, flowing CO2 at the cathode is essential for either conventional molten carbonate fuel cells (MCFCs) based on molten carbonate/LiAlO2 electrolytes or matrix-free MCFCs. For the first time, we demonstrate a high-performance matrix-free MCFC without CO2 recirculation. At 800°C, power densities of 430 and 410 mW/cm(2) are achieved when biomass-bamboo charcoal and wood, respectively-is used as fuel. At 600°C, a stable performance is observed during the measured 90 hours after the initial degradation. In this MCFC, CO2 is produced at the anode when carbon-containing fuels are used. The produced CO2 then dissolves and diffuses to the cathode to react with oxygen in open air, forming the required [Formula: see text] or [Formula: see text] ions for continuous operation. The dissolved [Formula: see text] ions may also take part in the cell reactions. This provides a simple new fuel cell technology to directly convert carbon-containing fuels such as carbon and biomass into electricity with high efficiency.

  6. Feasibility Study for The Setting Up of a Safety System for Monitoring CO2 Storage at Prinos Field, Greece

    NASA Astrophysics Data System (ADS)

    Koukouzas, Nikolaos; Lymperopoulos, Panagiotis; Tasianas, Alexandros; Shariatipour, Seyed

    2016-10-01

    Geological storage of CO2 in subsurface geological structures can mitigate global warming. A comprehensive safety and monitoring system for CO2 storage has been undertaken for the Prinos hydrocarbon field, offshore northern Greece; a system which can prevent any possible leakage of CO2. This paper presents various monitoring strategies of CO2 subsurface movement in the Prinos reservoir, the results of a simulation of a CO2 leak through a well, an environmental risk assessment study related to the potential leakage of CO2 from the seafloor and an overall economic insight of the system. The results of the simulation of the CO2 leak have shown that CO2 reaches the seabed in the form of gas approximately 13.7 years, from the beginning of injection. From that point onwards the amount of CO2 reaching the seabed increases until it reaches a peak at around 32.9 years. During the injection period, the CO2 plume develops only within the reservoir. During the post-injection period, the CO2 reaches the seabed and develops side branches. These correspond to preferential lateral flow pathways of the CO2 and are more extensive for the dissolved CO2 than for the saturated CO2 gas. For the environmental risk assessment, we set up a model, using ArcGIS software, based on the use of data regarding the speeds of the winds and currents encountered in the region. We also made assumptions related to the flow rate of CO2. Results show that after a period of 10 days from the start of CO2 leakage the CO2 has reached halfway to the continental shores where the “Natura” protected areas are located. CO2 leakage modelling results show CO2 to be initially flowing along a preferential flow direction, which is towards the NE. However, 5 days after the start of leakage of CO2, the CO2 is also flowing towards the ENE. The consequences of a potential CO2 leak are considered spatially limited and the ecosystem is itself capable of recovering. We have tried to determine the costs necessary for the

  7. High resolution fossil fuel combustion CO2 emission fluxes for the United States

    SciTech Connect

    Gurney, Kevin R.; Mendoza, Daniel L.; Zhou, Yuyu; Fischer, Marc L.; Miller, Chris C.; Geethakumar, Sarath; de la Rue du Can, Stephane

    2009-03-19

    Quantification of fossil fuel CO{sub 2} emissions at fine space and time resolution is emerging as a critical need in carbon cycle and climate change research. As atmospheric CO{sub 2} measurements expand with the advent of a dedicated remote sensing platform and denser in situ measurements, the ability to close the carbon budget at spatial scales of {approx}100 km{sup 2} and daily time scales requires fossil fuel CO{sub 2} inventories at commensurate resolution. Additionally, the growing interest in U.S. climate change policy measures are best served by emissions that are tied to the driving processes in space and time. Here we introduce a high resolution data product (the 'Vulcan' inventory: www.purdue.edu/eas/carbon/vulcan/) that has quantified fossil fuel CO{sub 2} emissions for the contiguous U.S. at spatial scales less than 100 km{sup 2} and temporal scales as small as hours. This data product, completed for the year 2002, includes detail on combustion technology and 48 fuel types through all sectors of the U.S. economy. The Vulcan inventory is built from the decades of local/regional air pollution monitoring and complements these data with census, traffic, and digital road data sets. The Vulcan inventory shows excellent agreement with national-level Department of Energy inventories, despite the different approach taken by the DOE to quantify U.S. fossil fuel CO{sub 2} emissions. Comparison to the global 1{sup o} x 1{sup o} fossil fuel CO{sub 2} inventory, used widely by the carbon cycle and climate change community prior to the construction of the Vulcan inventory, highlights the space/time biases inherent in the population-based approach.

  8. Application of Pressure Pulse Test Analysis in CO2 Leakage Detection and Monitoring

    NASA Astrophysics Data System (ADS)

    Shakiba, M.; Hosseini, S. A.

    2015-12-01

    Over the past decade, numerous research and industrial projects have been devoted to investigate the feasibility and efficiency of carbon dioxide capture, storage, and utilization. Besides the studies over the characteristics of candidate formations for CO2 injection, much attention has been paid to answer the environmental concerns regarding the CO2 leak to overlying formations. To first detect and then track a possible CO2 leak, different techniques have been proposed in the literature; however, most of them examine only a small portion of the formation and have a low resolution for early leak detection. To further increase the extent of the investigation zone and to monitor a large section of the formation in more detail, multi-well testing techniques have received a significant attention. Pressure pulse testing is a multi-well test technique in which a pressure signal generated by periods of injection and shut-in from a pulser well is propagated inside the formation, and the corresponding response is recorded at the observer wells. The recorded pressure response is then analyzed to measure the rock and fluid properties and to monitor the possible changes over the time. In this research study, we have applied frequency methods as well as superposition principle to interpret the pressure pulse test data and monitor the changes in transmissibility and storativity of the formation between the well pairs. We have used synthetic reservoir models and numerical reservoir simulations to produce the pressure pulse test data. The analysis of the simulation results indicated that even a small amount of CO2 leak in the investigation zone can have a measurable effect on the calculated storativity and transmissibility factors. This can be of a great importance when an early leak detection is of interest. Moreover, when multiple wells are available in the formation, the distribution of the calculated parameters can visualize the extent of CO2 leak, which has a great

  9. 40 CFR 600.209-12 - Calculation of vehicle-specific 5-cycle fuel economy and CO2 emission values for a model type.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-cycle fuel economy and CO2 emission values for a model type. 600.209-12 Section 600.209-12 Protection of... EMISSIONS OF MOTOR VEHICLES Procedures for Calculating Fuel Economy and Carbon-Related Exhaust Emission Values § 600.209-12 Calculation of vehicle-specific 5-cycle fuel economy and CO2 emission values for a...

  10. Real-time monitoring of CO2 storage sites: Application to Illinois Basin-Decatur Project

    USGS Publications Warehouse

    Picard, G.; Berard, T.; Chabora, E.; Marsteller, S.; Greenberg, S.; Finley, R.J.; Rinck, U.; Greenaway, R.; Champagnon, C.; Davard, J.

    2011-01-01

    Optimization of carbon dioxide (CO2) storage operations for efficiency and safety requires use of monitoring techniques and implementation of control protocols. The monitoring techniques consist of permanent sensors and tools deployed for measurement campaigns. Large amounts of data are thus generated. These data must be managed and integrated for interpretation at different time scales. A fast interpretation loop involves combining continuous measurements from permanent sensors as they are collected to enable a rapid response to detected events; a slower loop requires combining large datasets gathered over longer operational periods from all techniques. The purpose of this paper is twofold. First, it presents an analysis of the monitoring objectives to be performed in the slow and fast interpretation loops. Second, it describes the implementation of the fast interpretation loop with a real-time monitoring system at the Illinois Basin-Decatur Project (IBDP) in Illinois, USA. ?? 2011 Published by Elsevier Ltd.

  11. Results from twelve years of continuous monitoring of the soil CO2 flux at the Ketzin CO2 storage pilot site, Germany

    NASA Astrophysics Data System (ADS)

    Szizybalski, Alexandra; Zimmer, Martin; Pilz, Peter; Liebscher, Axel

    2017-04-01

    Under the coordination of the GFZ German Research Centre for Geosciences the complete life-cycle of a geological storage site for CO2 has been investigated and studied in detail over the past 12 years at Ketzin near Berlin, Germany. The test site is located at the southern flank of an anticlinal structure. Beginning with an exploration phase in 2004, drilling of the first three wells took place in 2007. From June 2008 to August 2013 about 67 kt of CO2 were injected into Upper Triassic sandstones at a depth of 630 to 650 m overlain by more than 165 m of shaley cap rocks. A comprehensive operational and scientific monitoring program forms the central part of the Ketzin project targeting at the reservoir itself, its overburden or above-zone and the surface. The surface monitoring is done by continuous soil CO2 flux measurements. These already started in 2005, more than three years prior to the injection phase using a survey chamber from LI-COR Inc. Twenty sampling locations were selected in the area of the anticline covering about 3 x 3 km. In order to obtain information on seasonal trends, measurements are performed at least once a month. The data set obtained prior to the injection serves as a basis for comparison with all further measurements during the injection and storage operations [Zimmer et al., 2010]. To refine the monitoring network, eight automatic, permanent soil CO2 flux stations were additionally installed in 2011 in the direct vicinity of the boreholes. Using this system, the CO2 soil flux is measured on an hourly basis. Over the whole monitoring time, soil temperature and moisture are recorded simultaneously and soil samples down to 70 cm depth were studied for their structure, carbon and nitrogen content. ver the whole monitoring time. Both, diurnal and seasonal flux variations can be detected and hence, provide a basis for interpretation of the measured data. Detailed analysis of the long-term monitoring at each station clearly reveals the influence

  12. Monitoring of injected CO2 using the seismic full waveform inversion for 2-D elastic VTI media

    NASA Astrophysics Data System (ADS)

    Kim, W. K.; Min, D. J.; KIM, S.; Shin, Y.; Moon, S.

    2014-12-01

    To monitor the injected CO2 in the subsurface, seismic monitoring techniques are extensively applied because of its high resolution. Among the seismic monitoring techniques, seismic full waveform inversion (FWI) has high applicability because it can delineate parameter changes by injected CO2. When seismic FWIs are applied, subsurface media can be generally assumed to be isotropic. However, most subsurface media are not isotropic, and shale is a representative anisotropic medium, particularly vertical transversely isotropic (VTI) medium, which is often encountered as a barrier to injected CO2. Thus, anisotropic properties of subsurface media are important for monitoring of injected CO2. For these issues, we need to consider anisotropy of subsurface media when seismic FWIs are applied as a monitoring tool for CO2 sequestration. In this study, we performed seismic FWI for 2-D elastic VTI media to investigate the effects of anisotropic properties in CO2 monitoring. For this numerical test, we assumed a geological model, which copies after one of CO2 storage prospects in Korea. We also applied seismic FWI algorithm for 2-D elastic isotropic media for comparison. From this comparison, we noticed that we can obtain more reliable results when we apply the anisotropic FWI algorithm. Numerical examples indicate that we should apply the anisotropic FWI algorithm rather than the isotropic FWI algorithm when we interpret seismic monitoring data acquired in anisotropic media to increase the success of monitoring for injected CO2. Our numerical results can also be used as references for real seismic monitoring of the Korea CO2 sequestration projects in the near future. Acknowledgements This work was supported by the Human Resources Development program (No. 20134010200510) of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korean government Ministry of Trade, Industry, and Energy and by the "Development of Technology for CO2 Marine

  13. Monitoring fugitive CH4 and CO2 emissions from a closed landfill at Tenerife, Canary Islands

    NASA Astrophysics Data System (ADS)

    Asensio-Ramos, María; Tompkins, Mitchell R. K.; Turtle, Lara A. K.; García-Merino, Marta; Amonte, Cecilia; Rodrígez, Fátima; Padrón, Eleazar; Melián, Gladys V.; Padilla, Germán; Barrancos, José; Pérez, Nemesio M.

    2017-04-01

    Solid waste must be managed systematically to ensure environmental best practices. One of the ways to manage this huge problem is to systematic dispose waste materials in locations such as landfills. However, landfills could face possible threats to the environment such as groundwater pollution and the release of landfill gases (CH4, volatile organic compounds, etc.) to the atmosphere. These structures should be carefully filled, monitored and maintained while they are active and for up to 30 years after they are closed. Even after years of being closed, a systematically amount of landfill gas could be released to the atmosphere through its surface in a diffuse and fugitive form. During the period 1999-2016, we have studied the spatial-temporal distribution of the surface fugitive emission of CO2 and CH4 into the atmosphere in a cell in the Arico's municipal landfill (0.3 km2) at Tenerife, Canary Islands, Spain. This cell was operative until 2004, when it was filled and closed. Monitoring these diffuse landfill emissions provides information of how the closed landfill is degassing. To do so, we have performed 9 gas emission surveys during the period 1999-2016. Surface landfill CO2 efflux measurements were carried out at around 450 sampling site by means of a portable non-dispersive infrared spectrophotometer (NDIR) model LICOR Li800 following the accumulation chamber method. Landfill gases taken in the chamber were analyzed using a double channel VARIAN 4900 micro-GC. CH4 efflux measurements were computed combining CO2 efflux measurements and CH4/CO2 ratio in the landfill's surface gas. To quantify the total CH4 emission, CH4 efflux contour map was constructed using sequential Gaussian simulation (sGs) as interpolation method. In general, a decrease in the CO2 emission is observed since the cell was closed (2004) to the present. The total CO2 and CH4 diffuse emissions estimated in the 2016 survey were 4.54 ± 0.14 t d-1 and 268.65 ± 17.99 t d-1, respectively

  14. Developing a monitoring and verification plan with reference to the Australian Otway CO2 pilot project

    SciTech Connect

    Dodds, K.; Daley, T.; Freifeld, B.; Urosevic, M.; Kepic, A.; Sharma, S.

    2009-05-01

    The Australian Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) is currently injecting 100,000 tons of CO{sub 2} in a large-scale test of storage technology in a pilot project in southeastern Australia called the CO2CRC Otway Project. The Otway Basin, with its natural CO{sub 2} accumulations and many depleted gas fields, offers an appropriate site for such a pilot project. An 80% CO{sub 2} stream is produced from a well (Buttress) near the depleted gas reservoir (Naylor) used for storage (Figure 1). The goal of this project is to demonstrate that CO{sub 2} can be safely transported, stored underground, and its behavior tracked and monitored. The monitoring and verification framework has been developed to monitor for the presence and behavior of CO{sub 2} in the subsurface reservoir, near surface, and atmosphere. This monitoring framework addresses areas, identified by a rigorous risk assessment, to verify conformance to clearly identifiable performance criteria. These criteria have been agreed with the regulatory authorities to manage the project through all phases addressing responsibilities, liabilities, and to assure the public of safe storage.

  15. A layer stripping approach for monitoring CO2 storage sites using surface magnetotelluric responses

    NASA Astrophysics Data System (ADS)

    Ogaya, X.; Ledo, J.; Queralt, P.; Jones, A. G.; Marcuello, A.

    2015-12-01

    In this work we present an approach, called "layer stripping", to enhance the sensitivity of surface magnetotelluric responses to subtle subsurface temporal variations in electrical resistivity. The proposed methodology is based on the analytical solution of the one-dimensional magnetotelluric problem, and that both resolution and sensitivity to resistivity changes produced at a given depth increase when the data are acquired closer to the depth where the resistivity changes are taking place. Thus, given a well-known geoelectrical baseline model of a reservoir site, the layer stripping approach aims to remove the effects of the upper, unchanging, structures in order to obtain the time-varying magnetotelluric responses at the target depth. The layer stripping methodology is suggested for monitoring all types of reservoirs but in this work we focus on its application on CO2 geological storage sites. Different injections of CO2 are studied simulating one-dimensional and three-dimensional resistivity variations in the reservoir layer, and the feasibility of the method is appraised evaluating the error of the approach. The geoelectrical baseline model of the Hontomín site (Spain) for CO2 geological storage in a deep saline aquifer is used to assess how this methodology could be implemented in an actual monitoring survey. The resistivity model of the site defines the subsurface in the pre-injection state and allows applying the layer stripping approach to remove the effect of the upper structures not affected by injection of the CO2 gas from the surface MT responses. The proposed approach constitutes an innovative contribution to detect resistivity variations and locate them more precisely in the space. The obtained results show the potential of the method also to sense any possible leakage.

  16. Seismic dynamic monitoring in CO2 flooding based on characterization of frequency-dependent velocity factor

    NASA Astrophysics Data System (ADS)

    Zhang, Jun-Hua; Li, Jun; Xiao, Wen; Tan, Ming-You; Zhang, Yun-Ying; Cui, Shi-Ling; Qu, Zhi-Peng

    2016-06-01

    The phase velocity of seismic waves varies with the propagation frequency, and thus frequency-dependent phenomena appear when CO2 gas is injected into a reservoir. By dynamically considering these phenomena with reservoir conditions it is thus feasible to extract the frequency-dependent velocity factor with the aim of monitoring changes in the reservoir both before and after CO2 injection. In the paper, we derive a quantitative expression for the frequency-dependent factor based on the Robinson seismic convolution model. In addition, an inversion equation with a frequency-dependent velocity factor is constructed, and a procedure is implemented using the following four processing steps: decomposition of the spectrum by generalized S transform, wavelet extraction of cross-well seismic traces, spectrum equalization processing, and an extraction method for frequency-dependent velocity factor based on the damped least-square algorithm. An attenuation layered model is then established based on changes in the Q value of the viscoelastic medium, and spectra of migration profiles from forward modeling are obtained and analyzed. Frequency-dependent factors are extracted and compared, and the effectiveness of the method is then verified using a synthetic data. The frequency-dependent velocity factor is finally applied to target processing and oil displacement monitoring based on real seismic data obtained before and after CO2 injection in the G89 well block within Shengli oilfield. Profiles and slices of the frequency-dependent factor determine its ability to indicate differences in CO2 flooding, and the predicting results are highly consistent with those of practical investigations within the well block.

  17. Stored CO2 and Methane Leakage Risk Assessment and Monitoring Tool Development: CO2 Capture Project Phase 2 (CCP2)

    SciTech Connect

    Dan Kieki

    2008-09-30

    The primary project goal is to develop and test tools for optimization of ECBM recovery and geologic storage of CO{sub 2} in coalbeds, in addition to tools for monitoring CO{sub 2} sequestration in coalbeds to support risk assessment. Three critical topics identified are (1) the integrity of coal bed methane geologic and engineered systems, (2) the optimization of the coal bed storage process, and (3) reliable monitoring and verification systems appropriate to the special conditions of CO{sub 2} storage and flow in coals.

  18. A unique noninvasive approach to monitoring dissolved O2 and CO2 in cell culture.

    PubMed

    Chatterjee, Madhubanti; Ge, Xudong; Uplekar, Shaunak; Kostov, Yordan; Croucher, Leah; Pilli, Manohar; Rao, Govind

    2015-01-01

    Although online monitoring of dissolved oxygen (DO) and carbon dioxide (DCO2 ) is highly desirable in bioprocesses, small-scale bioreactors are usually not monitored due to the lack of suitable sensors. Traditional electrochemical sensors are usually not used because they are bulky and invasive. Disposable optical sensors are small and only partially invasive, but there are concerns regarding the toxicity of the patch and the phototoxicity of the illuminating light. Here we present a novel, noninvasive, rate-based technique for monitoring DO and DCO2 in cell cultures. A silicone sampling loop which allowed the diffusion of O2 and CO2 through its wall was inserted inside a bioreactor, and then flushed with N2 until the CO2 and O2 inside the loop were completely removed. The gas inside the loop was then allowed to recirculate through gas impermeable tubing to the O2 and CO2 sensors. We have shown that by measuring the initial diffusion rate we were able to determine the partial pressures of the two gases in the culture. The technique could be readily automated and measurements could be made in minutes. It was tested in demonstration experiments by growing murine hybridoma cells in a T-flask and a spinner-flask at 37°C. The results were comparable to those measured with commercially available fluorescence-based patch sensors. These results show that the rate-based method is an effective way to monitor small-scale cell cultures. This measurement mechanism can be easily built into disposable cell culture vessels for facile use. © 2014 Wiley Periodicals, Inc.

  19. Diffuse CO_{2} and ^{222}Rn degassing monitoring of Ontake volcano, Japan

    NASA Astrophysics Data System (ADS)

    Alonso, Mar; Sagiya, Takeshi; Meneses-Gutiérrez, Ángela; Padrón, Eleazar; Hernández, Pedro A.; Pérez, Nemesio M.; Melián, Gladys; Padilla, Germán D.

    2017-04-01

    Mt. Ontake (3067 m.a.s.l.) is a stratovolcano located in central Honsu and around 100 Km northeast of Nagoya, Japan, with the last eruption occurring on September 27, 2014, killing 57 people, and creating a 7-10 km high ash plume (Kagoshima et. al., 2016). There were no significant earthquakes that might have warned authorities in the lead up to the phreatic eruption, caused by ground water flashing to steam in a hydrothermal explosion. At the time of the eruption there was no operational geochemical surveillance program. In order to contribute to the strengthening of this program, the Disaster Mitigation Research Center of Nagoya University and the Volcanological Institute of Canary Islands started a collaborative program. To do so, an automatic geochemical station was installed at Ontake volcano and a survey of diffuse CO2efflux and other volatiles was carried out at the surface environment of selected areas of the volcano. The station was installed 10.9 km east away from the eruptive vent, where some earthquakes occurred, and consists of a soil radon (Rn) monitor (SARAD RTM-2010-2) able to measure 222Rn and 220Rn activities. Monitoring of radon is an important geochemical tool to forecast earthquakes and volcanic eruptions due to its geochemical properties. Rn ascends from the lower to the upper part of earth's crust mainly through cracks or faults and its transport needs the existence of a naturally occurring flux of a carrier gas. Regarding to the soil gas survey, it was carried out in August 2016 with 183 measurement points performed in an area of 136 km2. Measurements of soil CO2 efflux were carried out following the accumulation chamber method by means of a portable soil CO2 efflux instrument. To estimate the total CO2 output, sequential Gaussian simulation (sGs) was used allowing the interpolation of the measured variable at not-sampled sites and assess the uncertainly of the total diffuse emission of carbon dioxide estimated for the entire studied area

  20. Improving the temporal and spatial distribution of CO2 emissions from global fossil fuel emission data sets

    NASA Astrophysics Data System (ADS)

    Nassar, Ray; Napier-Linton, Louis; Gurney, Kevin R.; Andres, Robert J.; Oda, Tomohiro; Vogel, Felix R.; Deng, Feng

    2013-01-01

    Through an analysis of multiple global fossil fuel CO2 emission data sets, Vulcan emission data for the United States, Canada's National Inventory Report, and NO2 variability based on satellite observations, we derive scale factors that can be applied to global emission data sets to represent weekly and diurnal CO2 emission variability. This is important for inverse modeling and data assimilation of CO2, which use in situ or satellite measurements subject to variability on these time scales. Model simulations applying the weekly and diurnal scaling show that, although the impacts are minor far away from sources, surface atmospheric CO2 is perturbed by up to 1.5-8 ppm and column-averaged CO2 is perturbed by 0.1-0.5 ppm over some major cities, suggesting the magnitude of model biases for urban areas when these modes of temporal variability are not represented. In addition, we also derive scale factors to account for the large per capita differences in CO2 emissions between Canadian provinces that arise from differences in per capita energy use and the proportion of energy generated by methods that do not emit CO2, which are not accounted for in population-based global emission data sets. The resulting products of these analyses are global 0.25° × 0.25° gridded scale factor maps that can be applied to global fossil fuel CO2 emission data sets to represent weekly and diurnal variability and 1° × 1° scale factor maps to redistribute spatially emissions from two common global data sets to account for differences in per capita emissions within Canada.

  1. High-resolution mapping of biogenic carbon fluxes to improve urban CO2 monitoring, reporting, and verification

    NASA Astrophysics Data System (ADS)

    Hardiman, B. S.; Hutyra, L.; Gately, C.; Raciti, S. M.

    2014-12-01

    Urban areas are home to 80% of the US population and 70% of energy related fossil fuel emissions originate from urban areas. Efforts to accurately monitor, report, and verify anthropogenic CO2 missions using atmospheric measurements require reliable partitioning of anthropogenic and biogenic sources. Anthropogenic emissions peak during the daytime, coincident with biogenic drawdown of CO2. In contrast, biogenic respiration emissions peak at night when anthropogenic emissions are lower. This temporal aliasing of fluxes requires careful modeling of both biogenic and anthropogenic fluxes for accurate source attribution through inverse modeling. Biogenic fluxes in urban regions can be a significant component of the urban carbon cycle. However, vegetation in urban areas is subject to longer growing seasons, reduced competition, higher rates of nitrogen deposition, and altered patterns of biomass inputs, all interacting to elevate C turnover rates relative to analogous non-urban ecosystems. These conditions suggest that models that ignore urban vegetation or base biogenic flux estimates on non-urban forests are likely to produce inaccurate estimates of anthropogenic CO2 emissions. Biosphere models often omit biogenic fluxes in urban areas despite potentially extensive vegetation coverage. For example, in Massachusetts, models mask out as much as 40% of land area, effectively assuming they have no biological flux. This results in a ~32% underestimate of aboveground biomass (AGB) across the state as compared to higher resolution vegetation maps. Our analysis suggests that some common biomass maps may underestimate forest biomass by ~520 Tg C within the state of Massachusetts. Moreover, omitted portions of the state have the highest population density, indicating that we know least about regions where most people live. We combine remote sensing imagery of urban vegetation cover with ground surveys of tree growth and mortality to improve estimates of aboveground biomass and

  2. Land and Water Use, CO2 Emissions, and Worker Radiological Exposure Factors for the Nuclear Fuel Cycle

    SciTech Connect

    Brett W Carlsen; Brent W Dixon; Urairisa Pathanapirom; Eric Schneider; Bethany L. Smith; Timothy M. AUlt; Allen G. Croff; Steven L. Krahn

    2013-08-01

    The Department of Energy Office of Nuclear Energy’s Fuel Cycle Technologies program is preparing to evaluate several proposed nuclear fuel cycle options to help guide and prioritize Fuel Cycle Technology research and development. Metrics are being developed to assess performance against nine evaluation criteria that will be used to assess relevant impacts resulting from all phases of the fuel cycle. This report focuses on four specific environmental metrics. • land use • water use • CO2 emissions • radiological Dose to workers Impacts associated with the processes in the front-end of the nuclear fuel cycle, mining through enrichment and deconversion of DUF6 are summarized from FCRD-FCO-2012-000124, Revision 1. Impact estimates are developed within this report for the remaining phases of the nuclear fuel cycle. These phases include fuel fabrication, reactor construction and operations, fuel reprocessing, and storage, transport, and disposal of associated used fuel and radioactive wastes. Impact estimates for each of the phases of the nuclear fuel cycle are given as impact factors normalized per unit process throughput or output. These impact factors can then be re-scaled against the appropriate mass flows to provide estimates for a wide range of potential fuel cycles. A companion report, FCRD-FCO-2013-000213, applies the impact factors to estimate and provide a comparative evaluation of 40 fuel cycles under consideration relative to these four environmental metrics.

  3. Time-lapse downhole electrical resistivity monitoring of subsurface CO2 storage at the Maguelone shallow experimental site (Languedoc, France)

    NASA Astrophysics Data System (ADS)

    Denchik, Nataliya; Pezard, Philippe; Lofi, Johanna; Perroud, Hervé; Neyens, Denis; Luquot, Linda

    2015-04-01

    A shallow field experimental site for CO2 injection was established at Maguelone (Languedoc,France), in order to test in an integrated manner a suite of surface and downhole hydrogeophysical monitoring methods. The objective is to improve our understanding of gas transport in the shallow subsurface and to determine the sensitivity of CO2 monitoring systems for leakage detection. The site offers a natural laboratory to study the processes associated with CO2 injection in a clastic and clay-rich context saturated with saline fluids. Prior to CO2injection, three nitrogen (N2) injections were undertaken in 2012 to measure the site response to neutral gas injection. In 2013, a volume of 111 m3 of CO2 was injected during 3.5 hours at 15 meter depth. During each experiment, the gas plumes were successfully detected from pressure monitoring, time-lapse induction logging and downhole resistivity monitoring with downhole dipole-dipole arrays. Increases in resistivity are attributed to free gas propagation (either N2 or CO2) whereas decreases in resistivity correlate with CO2 dissolution in the pore fluid. Chemical analyses confirm this hypothesis with a decrease in pH and an increase in the concentration of dissolved species in the later case. The next stage of the project will be performing the CO2 injection experiments with improved monitoring schema using results of the present study. In perspective, besides of improving our understanding of gas transport in the shallow subsurface, the additional issues could not just show a capability of used geophysical and geochemical techniques to monitor the CO2 plume and to detect near-surface CO2 migration pathways, but to help quantifying potential CO2 migration.

  4. Direct PEM fuel cell using "organic chemical hydrides" with zero-CO2 emission and low-crossover.

    PubMed

    Kariya, Nobuko; Fukuoka, Atsushi; Ichikawa, Masaru

    2006-04-14

    A series of "organic chemical hydrides" such as cyclohexane, methylcyclohexane, cyclohexene, 2-propanol, and cyclohexanol were applied to the direct PEM fuel cell. High performances of the PEM fuel cell were achieved by using cyclohexane (OCV = 920 mV, PD(max) = 15 mW cm(-2)) and 2-propanol (OCV = 790 mV, PD(max) = 78 mW cm(-2)) as fuels without CO(2) emissions. The rates of fuel crossover for cyclohexane, 2-propanol, and methanol were estimated, and the rates of fuel permeation of cyclohexane and 2-propanol were lower than that of methanol. Water electrolysis and electro-reductive hydrogenation of acetone mediated by PEM were carried out and formation of 2-propanol in cathode side was observed. This system is the first example of a "rechargeable" direct fuel cell.

  5. PEM fuel cell monitoring system

    DOEpatents

    Meltser, M.A.; Grot, S.A.

    1998-06-09

    Method and apparatus are disclosed for monitoring the performance of H{sub 2}--O{sub 2} PEM fuel cells. Outputs from a cell/stack voltage monitor and a cathode exhaust gas H{sub 2} sensor are corrected for stack operating conditions, and then compared to predetermined levels of acceptability. If certain unacceptable conditions coexist, an operator is alerted and/or corrective measures are automatically undertaken. 2 figs.

  6. PEM fuel cell monitoring system

    DOEpatents

    Meltser, Mark Alexander; Grot, Stephen Andreas

    1998-01-01

    Method and apparatus for monitoring the performance of H.sub.2 --O.sub.2 PEM fuel cells. Outputs from a cell/stack voltage monitor and a cathode exhaust gas H.sub.2 sensor are corrected for stack operating conditions, and then compared to predetermined levels of acceptability. If certain unacceptable conditions coexist, an operator is alerted and/or corrective measures are automatically undertaken.

  7. CO2 Outgassing from an Urbanized River System Fueled by Wastewater Treatment Plant Effluents.

    PubMed

    Yoon, Tae Kyung; Jin, Hyojin; Begum, Most Shirina; Kang, Namgoo; Park, Ji-Hyung

    2017-09-19

    Continuous underway measurements were combined with a basin-scale survey to examine human impacts on CO2 outgassing in a highly urbanized river system in Korea. While the partial pressure of CO2 (pCO2) was measured at 15 sites using syringe equilibration, 3 cruises employing an equilibrator were done along a 30 km transect in the Seoul metropolitan area. The basin-scale survey revealed longitudinal increases in surface water pCO2 and dissolved organic carbon (DOC) in the downstream reach. Downstream increases in pCO2, DOC, fluorescence index, and inorganic N and P reflected disproportionately large contributions from wastewater treatment plant (WWTP) effluents carried by major urban tributaries. Cruise transects exhibited strong localized peaks of pCO2 up to 13 000 μatm and (13)CO2 enrichment along the confluences of tributaries at an average flow, whereas CO2 pulses were dampened by increased flow during the monsoon period. Fluctuations in pCO2 along the eutrophic reach downstream of the confluences reflected environmental controls on the balance between photosynthesis, biodegradation, and outgassing. The results underscore WWTP effluents as an anthropogenic source of nutrients, DOC, and CO2 and their influences on algal blooms and associated C dynamics in eutrophic urbanized river systems, warranting further research on urbanization-induced perturbations to riverine metabolic processes and carbon fluxes.

  8. Investigation of Redox Metal Oxides for Carbonaceous Fuel Conversion and CO2 Capture

    NASA Astrophysics Data System (ADS)

    Galinsky, Nathan Lee

    The chemical looping combustion (CLC) process uses metal oxides, also referred to as oxygen carriers, in a redox scheme for conversion of carbonaceous fuels into a concentrated stream of CO2 and steam while also producing heat and electricity. The unique redox scheme of CLC allows CO2 capture with minimal energy penalty. The CLC process performance greatly depends on the oxygen carrier that is chosen. To date, more than 1000 oxygen carriers have been developed for chemical-looping processes using metal oxides containing first-row transition metals. Oxygen carriers are typically mixed with an inert ceramic support to improve their overall mechanical stability and recyclability. This study focuses on design of (i) iron oxide oxygen carriers for conversion of gaseous carbonaceous fuels and (ii) development of perovskite CaMnO 3-d with improved stability and redox properties for conversion of solid fuels. Iron oxide is cheap and environmentally benign. However, it suffers from low activity with carbonaceous fuels due partially to the low ionic conductivity of iron oxides. In order to address the low activity of iron-oxide-based oxygen carriers, support addition has been shown to lower the energy barrier of oxygen anion transport within the oxygen carrier. This work adds a mixed-ionic-and-electronic-conductor (MIEC) support to iron oxide to help facilitate O2- transport inside the lattice of iron oxide. The MIEC-supported iron oxide is compared to commonly used supports including TiO2 and Al2O 3 and the pure ionic conductor support yttria-stabilized zirconia (YSZ) for conversion of different carbonaceous fuels and hydrogen. Results show that the MIEC-supported iron oxide exhibits up to 70 times higher activity than non-MIEC-supported iron oxides for methane conversion. The MIEC supported iron oxide also shows good recyclability with only minor agglomeration and carbon formation observed. The effect of support-iron oxide synergies is further investigated to understand

  9. The Significance of Transcutaneous Continuous Overnight CO2 Monitoring in Determining Initial Mechanical Ventilator Application for Patients with Neuromuscular Disease

    PubMed Central

    Lee, Soon Kyu; Kim, Dong-hyun; Choi, Won Ah; Won, Yu Hui; Kim, Sun Mi

    2012-01-01

    Objective To reveal the significance of continuous transcutaneous carbon dioxide (CO2) level monitoring through reviewing cases which showed a discrepancy in CO2 levels between arterial blood gas analysis (ABGA) and continuous transcutaneous blood gas monitoring. Method Medical record review was conducted retrospectively of patients with neuromuscular diseases who had started home mechanical ventilation between June 2008 and May 2010. The 89 patients underwent ABGA at the 1st hospital day, and changes to their CO2 level were continuously monitored overnight with a transcutaneous blood gas analysis device. The number of patients who initially appeared to show normal PaCO2 through ABGA, yet displayed hypercapnea through overnight continuous monitoring, was counted. Results 36 patients (40.45%) presented inconsistent CO2 level results between ABGA and continuous overnight monitoring. The mean CO2 level of the 36 patients using ABGA was 37.23±5.11 mmHg. However, the maximum and mean CO2 levels from the continuous monitoring device were 52.25±6.87 mmHg and 46.16±6.08 mmHg, respectively. From the total monitoring period (357.28±150.12 minutes), CO2 retention over 45 mmHg was detected in 198.97 minutes (55.69%). Conclusion Although ABGA only reflects ventilatory status at the puncturing moment, ABGA results are commonly used to monitor ventilatory status in most clinical settings. In order to decide the starting point of home mechanical ventilation in neuromuscular patients, continuous overnight monitoring should be considered to assess latent CO2 retention. PMID:22506245

  10. Synthetic seismic monitoring using reverse-time migration and Kirchhoff migration for CO2 sequestration in Korea

    NASA Astrophysics Data System (ADS)

    Kim, W.; Kim, Y.; Min, D.; Oh, J.; Huh, C.; Kang, S.

    2012-12-01

    During last two decades, CO2 sequestration in the subsurface has been extensively studied and progressed as a direct tool to reduce CO2 emission. Commercial projects such as Sleipner, In Salah and Weyburn that inject more than one million tons of CO2 per year are operated actively as well as test projects such as Ketzin to study the behavior of CO2 and the monitoring techniques. Korea also began the CCS (CO2 capture and storage) project. One of the prospects for CO2 sequestration in Korea is the southwestern continental margin of Ulleung basin. To monitor the behavior of CO2 underground for the evaluation of stability and safety, several geophysical monitoring techniques should be applied. Among various geophysical monitoring techniques, seismic survey is considered as the most effective tool. To verify CO2 migration in the subsurface more effectively, seismic numerical simulation is an essential process. Furthermore, the efficiency of the seismic migration techniques should be investigated for various cases because numerical seismic simulation and migration test help us accurately interpret CO2 migration. In this study, we apply the reverse-time migration and Kirchhoff migration to synthetic seismic monitoring data generated for the simplified model based on the geological structures of Ulleung basin in Korea. Synthetic seismic monitoring data are generated for various cases of CO2 migration in the subsurface. From the seismic migration images, we can investigate CO2 diffusion patterns indirectly. From seismic monitoring simulation, it is noted that while the reverse-time migration generates clear subsurface images when subsurface structures are steeply dipping, Kirchhoff migration has an advantage in imaging horizontal-layered structures such as depositional sediments appearing in the continental shelf. The reverse-time migration and Kirchhoff migration present reliable subsurface images for the potential site characterized by stratigraphical traps. In case of

  11. Characterization of a novel dissolved CO2 sensor for utilization in environmental monitoring and aquaculture industry

    NASA Astrophysics Data System (ADS)

    Balogh, K.; Jesus, João. M.; Gouveia, C.; Domingues, Jorge O.; Markovics, A.; Baptista, J. M.; Kovacs, B.; Pereira, Carlos M.; Borges, Maria-Teresa; Jorge, P. A. S.

    2013-11-01

    A novel optical fiber sensor is presented for measuring dissolved CO2 for water quality monitoring applications, where the optical signal is based either on refractive index changes or on color change. The sensing chemistry is based on the acid-basic equilibrium of 4-nitrophenol, that is converted into the anionic form by addition quaternary ammonium hydroxide. The CO2 sensitive layer was characterized and tested by using simple absorbance/reflectance measurement setups where the sensor was connected to a fiber optic CCD spectrometer. A prototype simulating a real shallow raceway aquaculture system was developed and its hydraulic behavior characterized. A commercially available partial-pressure- NDIR sensor was used as a reference for dissolved CO2 tests with the new optical fiber sensor under development. Preliminary tests allowed verifying the suitability of the new optical sensor for accurately tracking the dissolved carbon dioxide concentration in a suitable operation range. Direct comparison of the new sensor and the reference sensor system allowed to demonstrate the suitability of the new technology but also to identify some fragilities there are presently being addressed.

  12. Did dead animals really spew from the IEA-GHG Weyburn-Midale CO2 monitoring and storage project?

    NASA Astrophysics Data System (ADS)

    Rostron, B. J.; IEA-GHG Weyburn-Midale CO2 Project, T.; Theme Leaders: IEA-GHG Weyburn-Midale CO2 Monitoring; Storage Project

    2011-12-01

    The IEA-GHG Weyburn-Midale CO2 monitoring and storage project was initiated in 2000 to study the geological storage of CO2 as part of a CO2-EOR project in the Weyburn Field in Saskatchewan, Canada. Initial injection of CO2 began in October 2000, and continues to date, with more than 18 Mtonnes of anthropogenic CO2 stored in the Weyburn reservoir. In January 2011, a local landowner supported by a consultant's soil gas survey, claimed they had conclusive proof that the "source of the high concentrations of CO2 in soils ... is clearly the anthropogenic CO2 injected into the Weyburn reservoir". These claims quickly attracted local, provincial, national, and international media attention alerting the world to the "leakage" at the Weyburn CO2-EOR project and furthermore calling into question the safety of geological CO2 sequestration in general. A careful look at the data reveals a different story. Twenty six soil gas samples were collected in August 2010, from shallow (< 1m) drill holes and analyzed for CO2 concentrations and short-chain hydrocarbons. Six samples were analyzed for concentrations of stable isotopes of carbon, and four water samples from shallow dugouts were sampled for BTEX and hydrocarbons. Measured CO2 concentrations ranged from approximately 1 to 11%, methane concentrations ranged from approximately 1.2 to 24 ppm, and 13C/12C isotope concentrations ranged from -21.5 to -22.9 per mil. Hydrocarbons and BTEX in the water samples were below detection limits. Volumes of data collected by more than 80 international researchers in the IEA-GHG Weyburn-Midale research project, do not support the claim(s) of anthropogenic CO2 leakage from the Weyburn reservoir. A comprehensive geological, geophysical, hydrogeological, and geochemical site characterization combined with background and on-site soil gas monitoring, integrated with numerical simulations of CO2 movement has not detected any evidence of migration of CO2 above the regional subsurface seal. Shallow

  13. Modeling and Evaluation of Geophysical Methods for Monitoring and Tracking CO2 Migration

    SciTech Connect

    Daniels, Jeff

    2012-11-30

    Geological sequestration has been proposed as a viable option for mitigating the vast amount of CO{sub 2} being released into the atmosphere daily. Test sites for CO{sub 2} injection have been appearing across the world to ascertain the feasibility of capturing and sequestering carbon dioxide. A major concern with full scale implementation is monitoring and verifying the permanence of injected CO{sub 2}. Geophysical methods, an exploration industry standard, are non-invasive imaging techniques that can be implemented to address that concern. Geophysical methods, seismic and electromagnetic, play a crucial role in monitoring the subsurface pre- and post-injection. Seismic techniques have been the most popular but electromagnetic methods are gaining interest. The primary goal of this project was to develop a new geophysical tool, a software program called GphyzCO2, to investigate the implementation of geophysical monitoring for detecting injected CO{sub 2} at test sites. The GphyzCO2 software consists of interconnected programs that encompass well logging, seismic, and electromagnetic methods. The software enables users to design and execute 3D surface-to-surface (conventional surface seismic) and borehole-to-borehole (cross-hole seismic and electromagnetic methods) numerical modeling surveys. The generalized flow of the program begins with building a complex 3D subsurface geological model, assigning properties to the models that mimic a potential CO{sub 2} injection site, numerically forward model a geophysical survey, and analyze the results. A test site located in Warren County, Ohio was selected as the test site for the full implementation of GphyzCO2. Specific interest was placed on a potential reservoir target, the Mount Simon Sandstone, and cap rock, the Eau Claire Formation. Analysis of the test site included well log data, physical property measurements (porosity), core sample resistivity measurements, calculating electrical permittivity values, seismic data

  14. Uncertainty in projected climate change caused by methodological discrepancy in estimating CO2 emissions from fossil fuel combustion

    NASA Astrophysics Data System (ADS)

    Quilcaille, Yann; Gasser, Thomas; Ciais, Philippe; Lecocq, Franck; Janssens-Maenhout, Greet; Mohr, Steve; Andres, Robert J.; Bopp, Laurent

    2016-04-01

    There are different methodologies to estimate CO2 emissions from fossil fuel combustion. The term "methodology" refers to the way subtypes of fossil fuels are aggregated and their implied emissions factors. This study investigates how the choice of a methodology impacts historical and future CO2 emissions, and ensuing climate change projections. First, we use fossil fuel extraction data from the Geologic Resources Supply-Demand model of Mohr et al. (2015). We compare four different methodologies to transform amounts of fossil fuel extracted into CO2 emissions based on the methodologies used by Mohr et al. (2015), CDIAC, EDGARv4.3, and IPCC 1996. We thus obtain 4 emissions pathways, for the historical period 1750-2012, that we compare to the emissions timeseries from EDGARv4.3 (1970-2012) and CDIACv2015 (1751-2011). Using the 3 scenarios by Mohr et al. (2015) for projections till 2300 under the assumption of an Early (Low emission), Best Guess or Late (High emission) extraction peaking, we obtain 12 different pathways of CO2 emissions over 1750-2300. Second, we extend these CO2-only pathways to all co-emitted and climatically active species. Co-emission ratios for CH4, CO, BC, OC, SO2, VOC, N2O, NH3, NOx are calculated on the basis of the EDGAR v4.3 dataset, and are then used to produce complementary pathways of non-CO2 emissions from fossil fuel combustion only. Finally, the 12 emissions scenarios are integrated using the compact Earth system model OSCAR v2.2, in order to quantify the impact of the selected driver onto climate change projections. We find historical cumulative fossil fuel CO2 emissions from 1750 to 2012 ranging from 365 GtC to 392 GtC depending upon the methodology used to convert fossil fuel into CO2 emissions. We notice a drastic increase of the impact of the methodology in the projections. For the High emission scenario with Late fuel extraction peaking, cumulated CO2 emissions from 1700 to 2100 range from 1505 GtC to 1685 GtC; this corresponds

  15. Surrogate gas proxy prediction model for Delta 14C-based measurements of fossil fuel-CO2

    NASA Astrophysics Data System (ADS)

    Coakley, K. J.; Miller, J. B.; Montzka, S. A.; Sweeney, C.; Miller, B.

    2016-12-01

    The measured {}14}C {:12} {C isotopic ratio ofatmospheric CO2 (and its associated derived Δ 14Cvalue) is an ideal tracer for determination of the fossil fuelderived CO2 enhancement contributing to any atmosphericCO2 measurement (Cff). Given enough such measurements,independent top-down estimation of US fossil fuel- CO2emissions should be possible. However, the number of Δ 14Cmeasurements is presently constrained by cost, available samplevolume, and availability of mass spectrometer measurement facilities.Δ 14C is therefore measured in just a small fraction ofsamples obtained by flask air sampling networks around the world.Here, we develop a Projection Pursuit Regression model topredict Cff as a function of multiple surrogate gases acquiredwithin the NOAA/ESRL Global Greenhouse Gas Reference Network (GGGRN).The surrogates consist of measured enhancements of various anthropogenictrace gases, including CO, SF6, and halo- andhydro-carbons acquired in vertical airborne sampling profiles nearCape May, NJ and Portsmouth, NH from 2005 through 2010. Modelperformance is quantified based on predicted values correspondingto test data excluded from the model building process. Chi-squarehypothesis test analysis indicates that these predictions andcorresponding observations are consistent given our uncertaintybudget which accounts for random effects and one particular systematiceffect. To account for the possibility of additional systematiceffects, we incorporate another component of uncertainty into ourbudget. Provided that these estimates are of comparable qualityto Δ 14C -based estimates, we expect an improved determinationof fossil fuel-CO2 emissions.

  16. Uranium extraction from TRISO-coated fuel particles using supercritical CO2 containing tri-n-butyl phosphate.

    PubMed

    Zhu, Liyang; Duan, Wuhua; Xu, Jingming; Zhu, Yongjun

    2012-11-30

    High-temperature gas-cooled reactors (HTGRs) are advanced nuclear systems that will receive heavy use in the future. It is important to develop spent nuclear fuel reprocessing technologies for HTGR. A new method for recovering uranium from tristructural-isotropic (TRISO-) coated fuel particles with supercritical CO(2) containing tri-n-butyl phosphate (TBP) as a complexing agent was investigated. TRISO-coated fuel particles from HTGR fuel elements were first crushed to expose UO(2) pellet fuel kernels. The crushed TRISO-coated fuel particles were then treated under O(2) stream at 750°C, resulting in a mixture of U(3)O(8) powder and SiC shells. The conversion of U(3)O(8) into solid uranyl nitrate by its reaction with liquid N(2)O(4) in the presence of a small amount of water was carried out. Complete conversion was achieved after 60 min of reaction at 80°C, whereas the SiC shells were not converted by N(2)O(4). Uranyl nitrate in the converted mixture was extracted with supercritical CO(2) containing TBP. The cumulative extraction efficiency was above 98% after 20 min of online extraction at 50°C and 25 MPa, whereas the SiC shells were not extracted by TBP. The results suggest an attractive strategy for reprocessing spent nuclear fuel from HTGR to minimize the generation of secondary radioactive waste.

  17. Highly efficient visible light photocatalytic reduction of CO2 to hydrocarbon fuels by Cu-nanoparticle decorated graphene oxide.

    PubMed

    Shown, Indrajit; Hsu, Hsin-Cheng; Chang, Yu-Chung; Lin, Chang-Hui; Roy, Pradip Kumar; Ganguly, Abhijit; Wang, Chen-Hao; Chang, Jan-Kai; Wu, Chih-I; Chen, Li-Chyong; Chen, Kuei-Hsien

    2014-11-12

    The production of renewable solar fuel through CO2 photoreduction, namely artificial photosynthesis, has gained tremendous attention in recent times due to the limited availability of fossil-fuel resources and global climate change caused by rising anthropogenic CO2 in the atmosphere. In this study, graphene oxide (GO) decorated with copper nanoparticles (Cu-NPs), hereafter referred to as Cu/GO, has been used to enhance photocatalytic CO2 reduction under visible-light. A rapid one-pot microwave process was used to prepare the Cu/GO hybrids with various Cu contents. The attributes of metallic copper nanoparticles (∼4-5 nm in size) in the GO hybrid are shown to significantly enhance the photocatalytic activity of GO, primarily through the suppression of electron-hole pair recombination, further reduction of GO's bandgap, and modification of its work function. X-ray photoemission spectroscopy studies indicate a charge transfer from GO to Cu. A strong interaction is observed between the metal content of the Cu/GO hybrids and the rates of formation and selectivity of the products. A factor of greater than 60 times enhancement in CO2 to fuel catalytic efficiency has been demonstrated using Cu/GO-2 (10 wt % Cu) compared with that using pristine GO.

  18. Elevated atmospheric CO2 fuels leaching of old dissolved organic matter at the alpine treeline

    NASA Astrophysics Data System (ADS)

    Hagedorn, Frank; van Hees, Patrick A. W.; Handa, I. Tanya; HäTtenschwiler, Stephan

    2008-06-01

    Dissolved organic matter (DOM), the mobile form of soil organic matter (SOM), plays an important role in soil C cycling and in nutrient transport. We investigated the effects of 5 years of CO2 enrichment (370 versus 570 μmol CO2 mol-1) on DOM dynamics at the alpine treeline, including the analysis of fast-cycling components such as low molecular weight organic acids (LMWOAs), dissolved organic carbon (DOC) biodegradability, and the decomposition of 14C-labeled oxalate. Concentrations of DOC in canopy throughfall were 20% higher at elevated CO2, probably driven by higher carbohydrate concentrations in leaves. In the organic soil layer, 5 years of CO2 enrichment increased water-extractable organic C by 17% and soil solution DOC at 5 cm depth by 20%. The 13C tracing of recently assimilated CO2 revealed that the input of recent plant-derived C (<15% of total DOC) was smaller than the CO2-induced increase in DOC. This strongly suggests that CO2 enrichment enhanced the mobilization of native DOC, which is supported by significant increases in dissolved organic nitrogen (DON). We mainly attribute these increases to a stimulated microbial activity as indicated by higher basal and soil respiration rates (+27%). The 14C-labeled oxalate was more rapidly mineralized from high CO2 soils. The concentrations of LMWOAs, but also those of "hydrophilic" DOC and biodegradable DOC (6% of total DOC), were, however, not affected by elevated CO2, suggesting that production and consumption of "labile" DOC were in balance. In summary, our data suggest that 5 years of CO2 enrichment speeded up the cycling of "labile" DOM and SOM in a late successional treeline ecosystem and increased the mobilization of older DOM through a stimulated microbial activity. Such a "priming effect" implies that elevated CO2 can accelerate the turnover of native SOM, and thus, it may induce increasing losses of old C from thick organic layers.

  19. Experiments on the Deep Ocean Disposal of Fossil Fuel CO2

    NASA Astrophysics Data System (ADS)

    Brewer, P. G.; Peltzer, E. T.; Rehder, G.

    2001-12-01

    Deep ocean ROV experiments for the controlled release of CO2 have so far been limited by the small volume available for deployment, thus inhibiting observation of long life time effects, biological interactions, and macroscopic properties associated with sediment penetration. Early (1996) experiments released about 500ml per dive; later (1998) studies released volumes up to 7 liters per dive. We have developed and used a new large volume apparatus based upon a carbon fiber cylinder accumulator (79.5" long, 11" diameter, 150 lbs empty in air) with an internal volume of about 45 liters. For perspective present US CO2 releases are about 55 kg/person/day. The system is filled with liquid CO2 at about 1000 psi, and CO2 internal pressure is maintained above ambient by frequent hydraulic pumping of sea water to the open side of the accumulator during the dive. We have used this system to release 20-30 liter quantities into 20" diameter experimental corrals on the sea floor at 3600m depth, where the density of CO2 exceeds that of sea water. Earlier studies have shown the strong immiscibility of CO2 with sea water, and the apparent effect of a hydrate skin in inhibiting sediment penetration. We have now observed for the first time the formation of a large "frost heave" of CO2 hydrate within the surficial sediment 24 hours after the initial release. This is apparently caused by relatively rapid (~2 micromoles/cm2/sec) dissolution of CO2 hydrate at the sediment-CO2 interface, thus creating flow of dense CO2 saturated pore waters, followed by nucleation and growth of a hydrate mass which pushes apart the sediment matrix. Very large changes in pore water chemistry must follow, with pH < 3.7. Core recovery shows large releases of CO2 during retrieval, leading to the need for in situ measurement and/or pressure retaining samplers for accurate assessment.

  20. CO2-laser photoacoustic spectroscopy applied to low-level toxic-vapor monitoring

    NASA Astrophysics Data System (ADS)

    Loper, G. L.; Gelbwachs, J. A.; Beck, S. M.

    1986-09-01

    A CO2-laser photoacoustic detector is being developed that can detect the hazardous hydrazine-based rocket fuels and selected toxic industrial compounds at concentrations below 100 ppb in the ambient air. This paper reviews the work to develop this detector based on the principles of photoacoustic spectroscopy and classical acoustics. The low parts-per-billion level detection capability of the method to the hydrazines is demonstrated with both acoustically nonresonant and resonant photoacoustic cell designs. A flowing, resonant photoacoustic cell whose interior is coated with tetrafluoroethylene Teflon has been shown to be preferred for detecting highly adsorptive or reactive compounds. Photoacoustic spectroscopy has been demonstrated to be useful in measuring adsorption or reaction losses of low-concentration gases on surfaces.

  1. Microseismicity monitoring at the Decatur, IL, CO2 sequestration demonstration site

    NASA Astrophysics Data System (ADS)

    Kaven, J. Ole; Hickman, Stephen H.; McGarr, Arthur F.; Greenberg, Sallie

    2016-04-01

    Industrial-scale carbon capture and storage (CCS) will require the injection of large volumes of CO2 into extensive undisturbed brine aquifers. Large-volume injection has the potential to induce earthquake activity (Zoback and Gorelick, 2012). To assess the seismic hazard posed by one such operation, the USGS has been monitoring seismic activity at a CCS demonstration site in Decatur, IL, where supercritical CO2 is injected into the Mt. Simon Sandstone, a basal brine formation, at a depth of about 2 km, several 10s of meters above granitic basement. During the first phase of injection, supercritical CO2 was injected at a rate of about 1000 metric tons/day from November 2011 until November 2014. The USGS monitored microseismicity using a seismic network that consists of 16 stations (4 in 500 ft boreholes). The USGS data set contains 179 locatable events and shows that the microseismicity occurs in the Mt Simon sandstone injection interval and, to a lesser degree, in the pre-Mt Simon and the Precambrian basement. Microseismicity occurs in distinct clusters at varying distances from the injection well and distance from the well does not increase systematically with time. Double difference relocations of these events reveal that these clusters tend to form linear features in both the Mt. Simon and the basement, suggesting that the microseismicity involves reactivation of preexisting fractures and faults. This finding is corroborated by composite focal mechanisms for individual clusters that are consistent with the regional horizontal principal stress orientations and right-lateral slip across the reactivated faults and fractures. Despite the injection of nearly one million tons of CO2 the largest microearthquake magnitudes barely exceeded 1 and, thus, none of these events could be felt at the surface. During the second phase, injection down a second borehole will be at a rate of about 3000 metric tons/day starting in early 2016 and continue for three years. To augment

  2. Source Repeatability of Time-Lapse Offset VSP Surveys for Monitoring CO2 Injection

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Huang, L.; Rutledge, J. T.; Denli, H.; Zhang, H.; McPherson, B. J.; Grigg, R.

    2009-12-01

    Time-lapse vertical seismic profiling (VSP) surveys have the potential to remotely track the migration of injected CO2 within a geologic formation. To accurately detect small changes due to CO2 injection, the sources of time-lapse VSP surveys must be located exactly at the same positions. However, in practice, the source locations can vary from one survey to another survey. Our numerical simulations demonstrate that a variation of a few meters in the VSP source locations can result in significant changes in time-lapse seismograms. To address the source repeatability issue, we apply double-difference tomography to downgoing waves of time-lapse offset VSP data to invert for the source locations and the velocity structures simultaneously. In collaboration with Resolute Natural Resources, Navajo National Oil and Gas Company, and the Southwest Regional Partnership on Carbon Sequestration under the support of the U.S. Department of Energy’s National Energy Technology Laboratory, one baseline and two repeat offset VSP datasets were acquired in 2007-2009 for monitoring CO2 injection at the Aneth oil field in Utah. A cemented geophone string was used to acquire the data for one zero-offset and seven offset source locations. During the data acquisition, there was some uncertainty in the repeatability of the source locations relative to the baseline survey. Our double-difference tomography results of the Aneth time-lapse VSP data show that the source locations for different surveys are separated up to a few meters. Accounting for these source location variations during VSP data analysis will improve reliability of time-lapse VSP monitoring.

  3. Hopewell Beneficial CO2 Capture for Production of Fuels, Fertilizer and Energy

    SciTech Connect

    UOP; Honeywell Resins & Chemicals; Honeywell Process Solutions; Aquaflow Bionomics Ltd

    2010-09-30

    For Phase 1 of this project, the Hopewell team developed a detailed design for the Small Scale Pilot-Scale Algal CO2 Sequestration System. This pilot consisted of six (6) x 135 gallon cultivation tanks including systems for CO2 delivery and control, algal cultivation, and algal harvesting. A feed tank supplied Hopewell wastewater to the tanks and a receiver tank collected the effluent from the algal cultivation system. The effect of environmental parameters and nutrient loading on CO2 uptake and sequestration into biomass were determined. Additionally the cost of capturing CO2 from an industrial stack emission at both pilot and full-scale was determined. The engineering estimate evaluated Amine Guard technology for capture of pure CO2 and direct stack gas capture and compression. The study concluded that Amine Guard technology has lower lifecycle cost at commercial scale, although the cost of direct stack gas capture is lower at the pilot scale. Experiments conducted under high concentrations of dissolved CO2 did not demonstrate enhanced algae growth rate. This result suggests that the dissolved CO2 concentration at neutral pH was already above the limiting value. Even though dissolved CO2 did not show a positive effect on biomass growth, controlling its value at a constant set-point during daylight hours can be beneficial in an algae cultivation stage with high algae biomass concentration to maximize the rate of CO2 uptake. The limited enhancement of algal growth by CO2 addition to Hopewell wastewater was due at least in part to the high endogenous CO2 evolution from bacterial degradation of dissolved organic carbon present at high levels in the wastewater. It was found that the high level of bacterial activity was somewhat inhibitory to algal growth in the Hopewell wastewater. The project demonstrated that the Honeywell automation and control system, in combination with the accuracy of the online pH, dissolved O2, dissolved CO2, turbidity, Chlorophyll A and

  4. Radon isotope measurements as a monitoring tool for CO2 leakage in geological storage

    NASA Astrophysics Data System (ADS)

    Grandia, F.; Mazadiego, L. F.; de Elío, J.; Ortega, M.; Bruno, J.

    2011-12-01

    Early detection of the failure of the seal integrity is fundamental in the monitoring plan of a deep geological CO2 storage. A number of methods of leakage control are based on changes in fluid geochemistry (shallow water, soil gases) providing valuable indicators. Among them, the measurement of CO2 fluxes in the soil-atmosphere interface is commonly used since it can be easily done using portable infra-red analyzers (i.e., accumulation chambers). However, initial emission of CO2 from storage horizon could be masked by fluxes from biological activity, limiting its applicability as an early alarm system. The measurement of fluxes of trace gas (Rn, He, VOC) that are virtually absent in the pre-injection baseline turns out a promising complementary method. The measurement of radon isotopes has been long used for the observation of mass transport from deep reservoirs to surface despite the flux of 222Rn and 220Rn is usually very limited in sedimentary basins due to the short half-life of these isotopes. The enhanced transport of radon in CO2 fluxes has been reported from natural systems, resulting in concentration in air up to several thousands of Bq/m3. In the frame of the Compostilla pilot plant project in Spain, a number of methodologies to measure radon emission are being tested in natural systems to select of the most reliable and cost-effective method to be used in leakage control. These methods are (1) Scintillation detector EDA RD-200, (2) Track Etch °, (3) Ionization Chamber and (4) alpha spectroscopy SARAD RTM 200. Some of them are capable of measuring the isotopes separately (SARAD) whereas others just detect the bulk radon concentration. Also, these methods follow distinct procedures and acquisition times. The studied natural sites are located in central and NE Spain (Campo de Calatrava and La Selva basins), and in central Italy (Arezzo basin). Apparently, radon isotopes (up 200000 Bq/m3) are measured far from parent isotopes, and they are coupled to

  5. Least-squares reverse-time migration of Cranfield VSP data for monitoring CO2 injection

    NASA Astrophysics Data System (ADS)

    TAN, S.; Huang, L.

    2012-12-01

    Cost-effective monitoring for carbon utilization and sequestration requires high-resolution imaging with a minimal amount of data. Least-squares reverse-time migration is a promising imaging method for this purpose. We apply least-squares reverse-time migration to a portion of the 3D vertical seismic profile data acquired at the Cranfield enhanced oil recovery field in Mississippi for monitoring CO2 injection. Conventional reverse-time migration of limited data suffers from significant image artifacts and a poor image resolution. Lease-squares reverse-time migration can reduce image artifacts and improves the image resolution. We demonstrate the significant improvements of least-squares reverse-time migration by comparing its migration images of the Cranfield VSP data with that obtained using the conventional reverse-time migration.

  6. CO2 as a carbon neutral fuel source via enhanced biomass gasification.

    PubMed

    Butterman, Heidi C; Castaldi, Marco J

    2009-12-01

    The gas evolution, mass decay behavior and energy content of several woods, grasses, and agricultural residues were examined with steam and CO(2) gasification using thermogravimetric analysis and gas chromatography. CO(2) concentrations were varied between 0 and 100% with steam as a coreactant. Carbon conversion was complete with 25% CO(2)/75% steam compared to 90% conversion with pure steam in the temperature range of 800-1000 degrees C. The largest effect was from 0-5% CO(2) introduction where CO concentration increased by a factor of 10 and H(2) decreased by a factor of 3.3 at 900 degrees C. Increasing CO(2) from 5 to 50% resulted in continued CO increases and H(2) decrease by a factor of 3 at 900 degrees C. This yielded a H(2)/CO ratio that could be adjusted from 5.5 at a 0% CO(2) to 0.25 at a 50% CO(2) concentration. Selection of the gasification parameters, such as heating rate, also enabled greater control in the separation of cellulose from lignin via thermal treatment. 100% CO(2) concentration enabled near complete separation of cellulose from lignin at 380 degrees C using a 1 degrees C min(-1) heating rate. Similar trends were observed with coal and municipal solid waste (MSW) as feedstock. The likely mechanism is the ability for CO(2) to enhance the pore structure, particularly the micropores, of the residual carbon skeleton after drying and devolatilization providing access for CO(2) to efficiently gasify the solid.

  7. Stability and coking of direct-methane solid oxide fuel cells: Effect of CO 2 and air additions

    NASA Astrophysics Data System (ADS)

    Pillai, Manoj; Lin, Yuanbo; Zhu, Huayang; Kee, Robert J.; Barnett, Scott A.

    This paper concerns the stability of anode-supported solid oxide fuel cells (SOFCs), operated with fuel mixtures of methane-CO 2 and methane-air. Stability, which was evaluated in terms of voltage decrease at constant current density, was affected by coke deposits. Chemically inert anode barrier layers were shown to enhance stability and to slow catalytic endothermic reforming reactions within the Ni-YSZ anode that otherwise caused deleterious temperature variations and cell cracking. Increasing the amount of CO 2 added to CH 4 fuel led to a wider stable operating range, yet had relatively little effect on SOFC performance. Button cells operated at 800 ° C with fuel streams of 75% CH 4 and 25% CO 2 achieved maximum power densities above 1 W/cm 2. Adding air to methane also increased stability. In the case of air addition, SOFC temperature increased as a consequence of exothermic partial-oxidation reforming chemistry. Models were developed to predict temperature and gas-composition profiles within the button cells. The simulation results were used to assist interpretation of the experimental observations.

  8. sparse-msrf:A package for sparse modeling and estimation of fossil-fuel CO2 emission fields

    SciTech Connect

    2014-10-06

    The software is used to fit models of emission fields (e.g., fossil-fuel CO2 emissions) to sparse measurements of gaseous concentrations. Its primary aim is to provide an implementation and a demonstration for the algorithms and models developed in J. Ray, V. Yadav, A. M. Michalak, B. van Bloemen Waanders and S. A. McKenna, "A multiresolution spatial parameterization for the estimation of fossil-fuel carbon dioxide emissions via atmospheric inversions", accepted, Geoscientific Model Development, 2014. The software can be used to estimate emissions of non-reactive gases such as fossil-fuel CO2, methane etc. The software uses a proxy of the emission field being estimated (e.g., for fossil-fuel CO2, a population density map is a good proxy) to construct a wavelet model for the emission field. It then uses a shrinkage regression algorithm called Stagewise Orthogonal Matching Pursuit (StOMP) to fit the wavelet model to concentration measurements, using an atmospheric transport model to relate emission and concentration fields. Algorithmic novelties described in the paper above (1) ensure that the estimated emission fields are non-negative, (2) allow the use of guesses for emission fields to accelerate the estimation processes and (3) ensure that under/overestimates in the guesses do not skew the estimation.

  9. Surface monitoring of microseismicity at the Decatur, Illinois, CO2 sequestration demonstration site

    USGS Publications Warehouse

    Kaven, Joern; Hickman, Stephen H.; McGarr, Arthur F.; Ellsworth, William L.

    2015-01-01

    Sequestration of CO2 into subsurface reservoirs can play an important role in limiting future emission of CO2 into the atmosphere (e.g., Benson and Cole, 2008). For geologic sequestration to become a viable option to reduce greenhouse gas emissions, large-volume injection of supercritical CO2 into deep sedimentary formations is required. These formations offer large pore volumes and good pore connectivity and are abundant (Bachu, 2003; U.S. Geological Survey Geologic Carbon Dioxide Storage Resources Assessment Team, 2013). However, hazards associated with injection of CO2 into deep formations require evaluation before widespread sequestration can be adopted safely (Zoback and Gorelick, 2012). One of these hazards is the potential to induce seismicity on pre-existing faults or fractures. If these faults or fractures are large and critically stressed, seismic events can occur with magnitudes large enough to pose a hazard to surface installations and, possibly more critical, the seal integrity of the cap rock. The Decatur, Illinois, carbon capture and storage (CCS) demonstration site is the first, and to date, only CCS project in the United States that injects a large volume of supercritical CO2 into a regionally extensive, undisturbed saline formation. The first phase of the Decatur CCS project was completed in November 2014 after injecting a million metric tons of supercritical CO2 over three years. This phase was led by the Illinois State Geological Survey (ISGS) and included seismic monitoring using deep borehole sensors, with a few sensors installed within the injection horizon. Although the deep borehole network provides a more comprehensive seismic catalog than is presented in this paper, these deep data are not publically available. We contend that for monitoring induced microseismicity as a possible seismic hazard and to elucidate the general patterns of microseismicity, the U.S. Geological Survey (USGS) surface and shallow borehole network described below

  10. 40 CFR 600.207-12 - Calculation and use of vehicle-specific 5-cycle-based fuel economy and CO2 emission values for...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Carbon-Related Exhaust Emission Values § 600.207-12 Calculation and use of vehicle-specific 5-cycle-based...-specific 5-cycle-based fuel economy and CO2 emission values for vehicle configurations. 600.207-12 Section... vehicle-specific 5-cycle city and highway fuel economy and CO2 emission values for each...

  11. 40 CFR 600.207-12 - Calculation and use of vehicle-specific 5-cycle-based fuel economy and CO2 emission values for...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Carbon-Related Exhaust Emission Values § 600.207-12 Calculation and use of vehicle-specific 5-cycle-based...-specific 5-cycle-based fuel economy and CO2 emission values for vehicle configurations. 600.207-12 Section... vehicle-specific 5-cycle city and highway fuel economy and CO2 emission values for each...

  12. End tidal CO2 monitoring in condition of constant ventilation: a useful guide during advanced cardiac life support.

    PubMed

    Pokorná, M; Andrlík, M; Necas, E

    2006-01-01

    Success of advanced cardiac life support (ACLS) depends on several factors: character and severity of the primary insult, time interval between cardiac arrest and effective basic life support (BLS) and the ensuing ACLS, patient's general condition before the insult, environmental circumstances and efficacy of BLS and ACLS. From these factors, only the efficacy of ACLS is under control of emergency personnel. The end tidal partial pressure of CO2 (P(ET)CO2) has been shown to be an indicator of the efficiency of ACLS and a general prognostic marker. In this study P(ET)CO2 was monitored during out-of hospital ACLS in three cases of cardiac arrest of different aetiology. The aetiology included lung oedema, tension pneumothorax and high voltage electric injury. P(ET)CO2 served for adjustments of ACLS. In these three cases the predictive value of P(ET)CO2 monitoring corresponded to previously reported recommendations.

  13. A MOX Fuel Attribute Monitor

    SciTech Connect

    Bliss, Mary; Jordan, David V.; Barnett, Debra S.; Redding, Rebecca L.; Pearce, Stephen K.

    2007-08-21

    Euratom performs safeguards monitoring of Fresh MOX fuel for domestic power production in the European Union. Video cameras monitor the reactor storage ponds. If video surveillance is lost for a certain amount of time a measurement is required to verify that no fuel was diverted. The attribute measurement to verify the continued presence of MOX fuel is neutron emission. Ideally this measurement would be made without moving or handling the fuel rod assembly. A prototype attribute measurement system was made using scintillating neutron sensitive glass waveguides developed by Pacific Northwest National Laboratory. Short lengths (5-20 cm) of the neutron sensitive fiber were mechanically spliced to 15 m lengths of commercial high numerical aperture fiber optic cable (Ceramoptec Optran Ultra 0.44). The light detector is a Hamamatsu R7400P photomultiplier tube. An electronics package was built to use the sensors with a GBS Elektronik MCA-166 multichannel analyzer and user interface. The MCA-166 is the system most commonly used by Euratom inspectors. It can also be run from a laptop computer using Maestro (Ortec) or other software. A MCNP model was made to compare to measurements made with several neutron sources including NIST traceable 252Cf.

  14. A MOX fuel attribute monitor

    NASA Astrophysics Data System (ADS)

    Bliss, Mary; Jordan, David V.; Barnett, Debra S.; Redding, Rebecca L.; Pearce, Stephen K.

    2007-08-01

    Euratom performs safeguards monitoring of Fresh MOX fuel for domestic power production in the European Union. Video cameras monitor the reactor storage ponds. If video surveillance is lost for a certain amount of time a measurement is required to verify that no fuel was diverted. The attribute measurement to verify the continued presence of MOX fuel is neutron emission. Ideally this measurement would be made without moving or handling the fuel rod assembly. A prototype attribute measurement system was made using scintillating neutron sensitive glass waveguides developed by Pacific Northwest National Laboratory. Short lengths (5-20 cm) of the neutron sensitive fiber were mechanically spliced to 15 m lengths of commercial high numerical aperture fiber optic cable (Ceramoptec Optran Ultra 0.44). The light detector is a Hamamatsu R7400P photomultiplier tube. An electronics package was built to use the sensors with a GBS Elektronik MCA-166 multichannel analyzer and user interface. The MCA-166 is the system most commonly used by Euratom inspectors. It can also be run from a laptop computer using Maestro (Ortec) or other software. A MCNP model was made to compare to measurements made with several neutron sources including NIST traceable 252Cf.

  15. Evaluating sensitivity of complex electrical methods for monitoring CO2 intrusion into a shallow groundwater system and associated geochemical transformations

    NASA Astrophysics Data System (ADS)

    Dafflon, B.; Wu, Y.; Hubbard, S. S.; Birkholzer, J. T.; Daley, T. M.; Pugh, J. D.; Peterson, J.; Trautz, R. C.

    2011-12-01

    A risk factor of CO2 storage in deep geological formations includes its potential to leak into shallow formations and impact groundwater geochemistry and quality. In particular, CO2 decreases groundwater pH, which can potentially mobilize naturally occurring trace metals and ions commonly absorbed to or contained in sediments. Here, geophysical studies (primarily complex electrical method) are being carried out at both laboratory and field scales to evaluate the sensitivity of geophysical methods for monitoring dissolved CO2 distribution and geochemical transformations that may impact water quality. Our research is performed in association with a field test that is exploring the effects of dissolved CO2 intrusion on groundwater geochemistry. Laboratory experiments using site sediments (silica sand and some fraction of clay minerals) and groundwater were initially conducted under field relevant CO2 partial pressures (pCO2). A significant pH drop was observed with inline sensors with concurrent changes in fluid conductivity caused by CO2 dissolution. Electrical resistivity and electrical phase responses correlated well with the CO2 dissolution process at various pCO2. Specifically, resistivity decreased initially at low pCO2 condition resulting from CO2 dissolution followed by a slight rebound because of the transition of bicarbonate into non-dissociated carbonic acid at lower pH slightly reducing the total concentration of dissociated species. Continuous electrical phase decreases were also observed, which are interpreted to be driven by the decrease of surface charge density (due to the decrease of pH, which approaches the PZC of the sediments). In general, laboratory experiments revealed the sensitivity of electrical signals to CO2 intrusion into groundwater formations and can be used to guide field data interpretation. Cross well complex electrical data are currently being collected periodically throughout a field experiment involving the controlled release of

  16. Current photosynthate fuels the nitrogen response of soil CO2 flux in a boreal forest

    NASA Astrophysics Data System (ADS)

    Marshall, John; Peichl, Matthias; Tarvainen, Lasse; Näsholm, Torgny; Öquist, Mats; Linder, Sune

    2017-04-01

    Nitrogen addition frequently reduces CO2 efflux from forest soils, but it has been unclear whether the effect is on fluxes of current photosynthate belowground or the oxidation of substrate to CO2. Pulse-chase and girdling experiments have shown that current photosynthate can be a major substrate for soil CO2 efflux, but these methods are unwieldy for describing seasonal patterns. In the current study, we placed transparent chambers on the soil surface beneath a forest canopy and measured the seasonal CO2 flux over three growing seasons (2012-2014) in a boreal Scots pine forest under repeated, heavy nitrogen (N) addition (50-100 kg N ha-1 yr-1). Net CO2 fluxes were measured every half hour using a unique system comprised of four large (each 20.3 m2 surface area) chambers, two each on the nitrogen treatment and the control. Base respiration rates (R0) and temperature sensitivity (Q10) were derived from nonlinear fits to the flux data. The Q10 was similar with or without N addition, but the nitrogen additions nearly halved the R0 values. Treatment differences in R0 appeared in May or June, peaked in July and August, and disappeared again in November. This pattern is consistent with the seasonality of photosynthesis at our boreal site. We estimated efflux in the absence of new photosynthate by extrapolating the May and November parameterization throughout the year. These extrapolations agreed with independent estimates through the winter snowpack and with the results of previous tracer and girdling experiments, supporting the contention that new photosynthate accounts for the nitrogen-induced reduction in CO2 efflux. Soil organic matter accumulated in the N addition treatment at a rate that quantitatively matched the reduction in CO2 efflux. We therefore conclude that the reduced CO2 efflux following N addition is due to a decrease in the oxidation of new photosynthate, whereas its delivery belowground remains unaltered.

  17. Passive and Active Seismic Monitoring of CO2-Storage at Ketzin

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Santonico, D.; Meekes, J. A. C.; Verdel, A. R.; Arts, R. J.

    2012-04-01

    Since July 2008, CO2 is injected into a saline aquifer near the town of Ketzin in Germany. The reservoir used for this purpose is located at a depth of about 650 m. For monitoring the CO2-migration in the reservoir close to the injection well, TNO installed and exploits, since August 2009, a 2D seismic array, with 3-component geophones at the surface, 4-component receivers at 50 meters depth and a central vertical array of 4-component receivers. This specific acquisition set-up was and is being used both for the recording of high-quality active time-lapse seismic data as well as for continuous passive seismic data recording. Two active 2D surveys that were acquired using shot lines in a close vicinity of the two monitoring wells have meanwhile been processed. A first analysis of these data already shows that the use of an array of buried receivers results in time-lapse data that offer a high S/N ratio, thereby suppressing both ambient noise and surface-related coherent noise. Therefore, this setup is expected to lead to an increased data repeatability as compared to conventional seismic acquisition with sensors mounted at the surface only. The passive seismic data that were recorded continuously with the same array since September 2009 are exploited following two, largely different, approaches: 1)Spectral-ratio data pre-processing and back-projection of identified seismic events. This approach is data-driven and allows handling of variations in data quality caused by temporal and spatial changes in environmental site conditions. The first results are presented here whereby two months of data were investigated. The large majority of the identified events appears to originate from a single location at the surface. A few weak events originating from the subsurface have also been observed. 2)Testing of a new technique called ambient noise seismic interferometry: continuous passive noise registrations are correlated with each other to produce P-wave reflections as if

  18. External CO2 and water supplies for enhancing electrical power generation of air-cathode microbial fuel cells.

    PubMed

    Ishizaki, So; Fujiki, Itto; Sano, Daisuke; Okabe, Satoshi

    2014-10-07

    Alkalization on the cathode electrode limits the electrical power generation of air-cathode microbial fuel cells (MFCs), and thus external proton supply to the cathode electrode is essential to enhance the electrical power generation. In this study, the effects of external CO2 and water supplies to the cathode electrode on the electrical power generation were investigated, and then the relative contributions of CO2 and water supplies to the total proton consumption were experimentally evaluated. The CO2 supply decreased the cathode pH and consequently increased the power generation. Carbonate dissolution was the main proton source under ambient air conditions, which provides about 67% of total protons consumed for the cathode reaction. It is also critical to adequately control the water content on the cathode electrode of air-cathode MFCs because the carbonate dissolution was highly dependent on water content. On the basis of these experimental results, the power density was increased by 400% (143.0 ± 3.5 mW/m(2) to 575.0 ± 36.0 mW/m(2)) by supplying a humid gas containing 50% CO2 to the cathode chamber. This study demonstrates that the simultaneous CO2 and water supplies to the cathode electrode were effective to increase the electrical power generation of air-cathode MFCs for the first time.

  19. The SMAP Level 4 Carbon PRODUCT for Monitoring Terrestrial Ecosystem-Atmosphere CO2 Exchange

    NASA Technical Reports Server (NTRS)

    Jones, L. A.; Kimball, J. S.; Madani, N.; Reichle, R. H.; Glassy, J.; Ardizzone, J/

    2016-01-01

    The NASA Soil Moisture Active Passive (SMAP) mission Level 4 Carbon (L4_C) product provides model estimates of Net Ecosystem CO2 exchange (NEE) incorporating SMAP soil moisture information as a primary driver. The L4_C product provides NEE, computed as total respiration less gross photosynthesis, at a daily time step and approximate 14-day latency posted to a 9-km global grid summarized by plant functional type. The L4_C product includes component carbon fluxes, surface soil organic carbon stocks, underlying environmental constraints, and detailed uncertainty metrics. The L4_C model is driven by the SMAP Level 4 Soil Moisture (L4_SM) data assimilation product, with additional inputs from the Goddard Earth Observing System, Version 5 (GEOS-5) weather analysis and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data. The L4_C data record extends from March 2015 to present with ongoing production. Initial comparisons against global CO2 eddy flux tower measurements, satellite Solar Induced Canopy Florescence (SIF) and other independent observation benchmarks show favorable L4_C performance and accuracy, capturing the dynamic biosphere response to recent weather anomalies and demonstrating the value of SMAP observations for monitoring of global terrestrial water and carbon cycle linkages.

  20. Monitoring CO2 drainage and imbibition in a heterogeneous sandstone using both seismic velocity and electrical resistivity measurements

    NASA Astrophysics Data System (ADS)

    Kim, Jongwook; Nam, Myung Jin; Matsuoka, Toshifumi

    2016-02-01

    In a laboratory fluid-injection experiment, seismic velocity and electrical resistivity were measured simultaneously to monitor injected carbon dioxide (CO2) during CO2 drainage and imbibition within a heterogeneous, clay-containing Tako sandstone sample. In the CO2 drainage process, supercritical CO2 (10 MPa at 40°C) was injected under a condition similar to that of an in situ reservoir. After the CO2 drainage process, water was injected into the CO2-injected sandstone for the CO2 imbibition stage. Employing strategies based on Gassmann fluid-substitution and Archie's equation, P-wave velocities and electrical resistivities were interpreted to evaluate CO2 saturation (SCO2). Estimated values of SCO2 during the CO2 drainage process were compared with those of volume-derived SCO2, which were obtained by evaluating the volumes of injected and drained fluid. When Tako sandstone SCO2 is < 0.1, SCO2 estimation from P-wave velocity based on the Gassmann-Brie equation (with e = 12) is more precise than resistivity index (RI)-based Archie's equation estimations from electrical resistivity. For further analysis, a modified RI equation was also employed to estimate SCO2, and the results were compared with those of the original RI-based Archie strategy.

  1. The CO2 release and Oxygen uptake from Fossil Fuel Emission Estimate (COFFEE) dataset: effects from varying oxidative ratios

    NASA Astrophysics Data System (ADS)

    Steinbach, J.; Gerbig, C.; Rödenbeck, C.; Karstens, U.; Minejima, C.; Mukai, H.

    2011-07-01

    We present a global dataset of CO2 emissions and O2 uptake associated with the combustion of different fossil fuel types. To derive spatial and temporal patterns of oxygen uptake, we combined high-resolution CO2 emissions from the EDGAR (Emission Database for Global Atmospheric Research) inventory with country level information on oxidative ratios, based on fossil fuel consumption data from the UN energy statistics database. The results are hourly global maps with a spatial resolution of 1°×1° for the years 1996-2008. The potential influence of spatial patterns and temporal trends in the resulting O2/CO2 emission ratios on the atmospheric oxygen signal is examined for different stations in the global measurement network, using model simulations from the global TM3 and the regional REMO transport model. For the station Hateruma Island (Japan, 24°03' N, 123°48' E), the simulated results are also compared to observations. In addition, the possibility of signals caused by variations in fuel use to be mistaken for oceanic signals is investigated using a global APO inversion.

  2. The CO2 release and Oxygen uptake from Fossil Fuel Emission Estimate (COFFEE) dataset: effects from varying oxidative ratios

    NASA Astrophysics Data System (ADS)

    Steinbach, J.; Gerbig, C.; Rödenbeck, C.; Karstens, U.; Minejima, C.; Mukai, H.

    2011-02-01

    We present a global dataset of CO2 emissions and O2 uptake associated with the combustion of different fossil fuel types. To derive spatial and temporal patterns of oxygen uptake, we combined high-resolution CO2 emissions from the EDGAR (Emission Database for Global Atmospheric Research) inventory with country level information on oxidative ratios, based on fossil fuel consumption data from the UN energy statistics database. The results are hourly global maps with a spatial resolution of 1° × 1° for the years 1996-2008. The potential influence of spatial patterns and temporal trends in the resulting O2/CO2 emission ratios on the atmospheric oxygen signal is examined for different stations in the global measurement network, using model simulations from the global TM3 and the regional REMO transport model. For the station Hateruma Island (Japan, 24° 03' N, 123° 48' E), the simulated results are also compared to observations. In addition, the possibility of signals caused by variations in fuel use to be mistaken for oceanic signals is investigated using a global APO inversion.

  3. Fuel-Flexible Gasification-Combustion Technology for Production of H2 and Sequestration-Ready CO2

    SciTech Connect

    George Rizeq; Parag Kulkarni; Wei Wei; Arnaldo Frydman; Thomas McNulty; Roger Shisler

    2005-11-01

    It is expected that in the 21st century the Nation will continue to rely on fossil fuels for electricity, transportation, and chemicals. It will be necessary to improve both the process efficiency and environmental impact performance of fossil fuel utilization. GE Global Research is developing an innovative fuel-flexible Unmixed Fuel Processor (UFP) technology to produce H{sub 2}, power, and sequestration-ready CO{sub 2} from coal and other solid fuels. The UFP module offers the potential for reduced cost, increased process efficiency relative to conventional gasification and combustion systems, and near-zero pollutant emissions including NO{sub x}. GE was awarded a contract from U.S. DOE NETL to develop the UFP technology. Work on the Phase I program started in October 2000, and work on the Phase II effort started in April 2005. In the UFP technology, coal and air are simultaneously converted into separate streams of (1) high-purity hydrogen that can be utilized in fuel cells or turbines, (2) sequestration-ready CO{sub 2}, and (3) high temperature/pressure vitiated air to produce electricity in a gas turbine. The process produces near-zero emissions with an estimated efficiency higher than IGCC with conventional CO2 separation. The Phase I R&D program established the feasibility of the integrated UFP technology through lab-, bench- and pilot-scale testing and investigated operating conditions that maximize separation of CO{sub 2} and pollutants from the vent gas, while simultaneously maximizing coal conversion efficiency and hydrogen production. The Phase I effort integrated experimental testing, modeling and preliminary economic studies to demonstrate the UFP technology. The Phase II effort will focus on three high-risk areas: economics, sorbent attrition and lifetime, and product gas quality for turbines. The economic analysis will include estimating the capital cost as well as the costs of hydrogen and electricity for a full-scale UFP plant. These costs will be

  4. Seismic Borehole Monitoring of CO2 Injection in an Oil Reservoir

    NASA Astrophysics Data System (ADS)

    Gritto, R.; Daley, T. M.; Myer, L. R.

    2002-12-01

    A series of time-lapse seismic cross well and single well experiments were conducted in a diatomite reservoir to monitor the injection of CO2 into a hydrofracture zone, based on P- and S-wave data. A high-frequency piezo-electric P-wave source and an orbital-vibrator S-wave source were used to generate waves that were recorded by hydrophones as well as three-component geophones. The injection well was located about 12 m from the source well. During the pre-injection phase water was injected into the hydrofrac-zone. The set of seismic experiments was repeated after a time interval of 7 months during which CO2 was injected into the hydrofractured zone. The questions to be answered ranged from the detectability of the geologic structure in the diatomic reservoir to the detectability of CO2 within the hydrofracture. Furthermore it was intended to determine which experiment (cross well or single well) is best suited to resolve these features. During the pre-injection experiment, the P-wave velocities exhibited relatively low values between 1700-1900 m/s, which decreased to 1600-1800 m/s during the post-injection phase (-5%). The analysis of the pre-injection S-wave data revealed slow S-wave velocities between 600-800 m/s, while the post-injection data revealed velocities between 500-700 m/s (-6%). These velocity estimates produced high Poisson ratios between 0.36 and 0.46 for this highly porous (~ 50%) material. Differencing post- and pre-injection data revealed an increase in Poisson ratio of up to 5%. Both, velocity and Poisson estimates indicate the dissolution of CO2 in the liquid phase of the reservoir accompanied by a pore-pressure increase. The single well data supported the findings of the cross well experiments. P- and S-wave velocities as well as Poisson ratios were comparable to the estimates of the cross well data.

  5. Creating a multi-gas proxy for Delta 14C and atmospheric fossil fuel-CO2. Kevin Coakley, John Miller , Scott Lehman, Stephen Montzka, Colm Sweeney, Arlyn Andrews , Ben Miller

    NASA Astrophysics Data System (ADS)

    Coakley, K. J.; Miller, J. B.; Lehman, S.; Montzka, S. A.; Andrews, A. E.; Miller, B. R.

    2013-12-01

    The C14:C12 ratio of atmospheric CO2 (expressed as Delta 14C) is the gold standard measurement to derive the portion of observed atmospheric CO2 gradients resulting from combustion of fossil fuels (CO2-ff). This is because fossil fuels are devoid of 14C, unlike all other sources and sinks that impact atmospheric Delta14C. With enough 14C measurements, independent, 'top-down', estimation of US fossil fuel-CO2 emissions should be possible. However, our ability to make carbon-14 measurements is severely constrained by cost, accessibility to accelerator mass spectrometers (AMS) and the volume of air required to make high precision (~0.2 %) measurements of 14CO2 (mixing ratio is ~ 4e-16 mol/mol). Thus, Delta 14C is currently measured in only a small subset of NOAA/ESRL Global Monitoring Division (GMD) tall-tower and aircraft air samples. Here, we present a Projection Pursuit Regression (PPR) model to predict CO2-ff measured at different times and altitudes in terms of surrogate gases that are more widespread and relatively inexpensive to measure. This method would, in effect, allow expansion of Delta 14C measurements by factor of ~3 or 4 throughout North America. To create a proxy for CO2-ff, we take advantage of the observed correlations between (Delta 14C-derrived) CO2-ff and regional-scale enhancements of a wide array of anthropogenic gases, like CO, SF6, and halo- and hydro-carbons. We select the complexity and form of the PPR model by cross validation where validation data prediction error is minimized. In cross validation, the prediction model is based on the training data and not the validation data. We quantify prediction model performance with test data excluded from the model development process. According to cross validation, the PPR model is superior to a simpler linear model. Comparison with test CO2-ff data shows that CO2-ff can be predicted with a root mean square error of 1.1 ppm, only slightly higher than the Delta 14C-precision limit for CO2-ff of 1

  6. Rb-stabilized laser at 1572 nm for CO2 monitoring

    NASA Astrophysics Data System (ADS)

    Matthey, R.; Moreno, W.; Gruet, F.; Brochard, P.; Schilt, S.; Mileti, G.

    2016-06-01

    We have developed a compact rubidium-stabilized laser system to serve as optical frequency reference in the 1.55-μm wavelength region, in particular for CO2 monitoring at 1572 nm. The light of a fiber-pigtailed distributed feedback (DFB) laser emitting at 1560 nm is frequency-doubled and locked to a sub-Doppler rubidium transition at 780 nm using a 2-cm long vapor glass cell. Part of the DFB laser light is modulated with an electro-optical modulator enclosed in a Fabry-Perot cavity, generating an optical frequency comb with spectral coverage extending from 1540 nm to 1580 nm. A second slave DFB laser emitting at 1572 nm and offset-locked to one line of the frequency comb shows a relative frequency stability of 1.10-11 at 1 s averaging time and <4.10-12 from 1 hour up to 3 days.

  7. Can satellite-based monitoring techniques be used to quantify volcanic CO2 emissions?

    NASA Astrophysics Data System (ADS)

    Schwandner, Florian M.; Carn, Simon A.; Kuze, Akihiko; Kataoka, Fumie; Shiomi, Kei; Goto, Naoki; Popp, Christoph; Ajiro, Masataka; Suto, Hiroshi; Takeda, Toru; Kanekon, Sayaka; Sealing, Christine; Flower, Verity

    2014-05-01

    Since 2010, we investigate and improve possible methods to regularly target volcanic centers from space in order to detect volcanic carbon dioxide (CO2) point source anomalies, using the Japanese Greenhouse gas Observing SATellite (GOSAT). Our long-term goals are: (a) better spatial and temporal coverage of volcano monitoring techniques; (b) improvement of the currently highly uncertain global CO2 emission inventory for volcanoes, and (c) use of volcanic CO2 emissions for high altitude, strong point source emission and dispersion studies in atmospheric science. The difficulties posed by strong relief, orogenic clouds, and aerosols are minimized by a small field of view, enhanced spectral resolving power, by employing repeat target mode observation strategies, and by comparison to continuous ground based sensor network validation data. GOSAT is a single-instrument Earth observing greenhouse gas mission aboard JAXA's IBUKI satellite in sun-synchronous polar orbit. GOSAT's Fourier-Transform Spectrometer (TANSO-FTS) has been producing total column XCO2 data since January 2009, at a repeat cycle of 3 days, offering great opportunities for temporal monitoring of point sources. GOSAT's 10 km field of view can spatially integrate entire volcanic edifices within one 'shot' in precise target mode. While it doesn't have any spatial scanning or mapping capability, it does have strong spectral resolving power and agile pointing capability to focus on several targets of interest per orbit. Sufficient uncertainty reduction is achieved through comprehensive in-flight vicarious calibration, in close collaboration between NASA and JAXA. Challenges with the on-board pointing mirror system have been compensated for employing custom observation planning strategies, including repeat sacrificial upstream reference points to control pointing mirror motion, empirical individualized target offset compensation, observation pattern simulations to minimize view angle azimuth. Since summer 2010

  8. [Measuring the calibration factor of a light scattering dust monitor for CO2 arc welding fumes].

    PubMed

    Ojima, Jun

    2002-12-01

    In Japan, a light scattering type digital dust monitor is most commonly used for dust concentration measurement in a working environment. In this study, the calibration factors of a digital dust monitor (K-factor) for several welding fumes were measured in a laboratory. During the experiment, fumes were generated from CO2 arc welding performed by an automatic welding robot. The examined welding wires were JIS Z 3312, Z 3313, Z 3315, Z 3317 and Z 3320. The mass and relative concentrations of the welding fumes were measured simultaneously by a total/respirable (TR) dust sampler and a digital dust monitor at a welding current of 100 A, 150 A, 200 A, 250 A and 300 A. The particle size distributions of welding fumes were measured by a low pressure impactor at a welding current of 100 A and 300 A. A significant effect of the welding current on the K-factor was recognized for all the examined wires. In the most remarkable case, a four-fold difference in the K-factors was found when the fumes were generated from a flux cored wire for mild steel (JIS Z 3313). The particle size distributions of fumes were also affected by the welding current. The coefficients of variation in the measured K-factor were 7.8-40.5%.

  9. Subtask 2.6 - Assessment of Alternative Fuels on CO2 Production

    SciTech Connect

    Debra Pflughoeft-Hassett; Darren Naasz

    2009-06-16

    Many coal-based electric generating units use alternative fuels, and this effort assessed the impact of alternative fuels on CO{sub 2} production and other emissions and also assessed the potential impact of changes in emission regulations under the Clean Air Act (CAA) for facilities utilizing alternative fuels that may be categorized as wastes. Information was assembled from publicly available U.S. Department of Energy Energy Information Administration databases that included alternative fuel use for 2004 and 2005. Alternative fuel types were categorized along with information on usage by coal-based electric, number of facilities utilizing each fuel type, and the heating value of solid, liquid, and gaseous alternative fuels. The sulfur dioxide, nitrogen oxide, and carbon dioxide emissions associated with alternative fuels and primary fuels were also evaluated. Carbon dioxide emissions are also associated with the transport of all fuels. A calculation of carbon dioxide emissions associated with the transport of biomass-based fuels that are typically accessed on a regional basis was made. A review of CAA emission regulations for coal-based electric generating facilities from Section 112 (1) and Section 129 (2) for solid waste incinerators was performed with consideration for a potential regulatory change from Section 112 (1) regulation to Section 129 (2). Increased emission controls would be expected to be required if coal-based electric generating facilities using alternative fuels would be recategorized under CAA Section 129 (2) for solid waste incinerators, and if this change were made, it is anticipated that coal-fired electric generating facilities might reduce the use of alternative fuels. Conclusions included information on the use profile for alternative fuels and the impacts to emissions as well as the impact of potential application of emission regulations for solid waste incinerators to electric generating facilities using alternative fuels.

  10. mCSEM inversion for CO2 sequestration monitoring at a deep brine aquifer in a shallow sea

    NASA Astrophysics Data System (ADS)

    Kang, Seogi; Noh, Kyubo; Seol, Soon Jee; Byun, Joongmoo

    2015-11-01

    Carbon dioxide injection monitoring in offshore environments is a promising future application of the marine controlled-source electromagnetic (mCSEM) method. To investigate whether the mCSEM method can be used to quantitatively monitor variations in the distribution of the injected CO2, we developed a mCSEM inversion scheme and conducted numerical analyses. Furthermore, to demonstrate the monitoring capability of the mCSEM method in challenging environments, we used a deep brine aquifer model in shallow sea as an injection target. The mCSEM responses of the injected CO2 in the deep brine aquifer were severely decayed and heavily masked by the air wave due to the proximity of the free space. Therefore, the accurate computation of small mCSEM responses due to the injected CO2 and the proper incorporation into the inversion process are critically important for the mCSEM method to be successful. Additionally, in monitoring situations, some useful a priori information is usually available (e.g. well logs and seismic sections), and the proper implementation of this to our inversion framework is crucial to ensure reliable estimation of the distribution of the injected CO2 plume. In this study, we developed an efficient 2.5D mCSEM inversion algorithm based on an accurate forward modelling algorithm and the judicious incorporation of a priori information into our inversion scheme. The inversion scheme was tested with simplified and realistic CO2 injection models and successfully recovered the resistivity distributions of the injected CO2, although it still required the presence of a considerable amount of the injected CO2. Based on these inversion experiments, we demonstrated that the mCSEM method is capable of quantitatively monitoring variations in the distribution of injected CO2 in offshore environments.

  11. EM Methods Applied for the Characterization and Monitoring of the Hontomin (Spain) CO2 Storage Pilot Plant

    NASA Astrophysics Data System (ADS)

    Ledo, Juanjo; Queralt, Pilar; Marcuello, Alex; Ogaya, Xenia; Vilamajo, Eloi; Bosch, David; Escalas, Lena; Piña, Perla

    2013-04-01

    The work presented here correspond to an on-going project in the frame of the development of a pilot plant for CO2 storage in a deep saline aquifer funded by Fundación Ciudad de la Energía-CIUDEN (http://www.ciuden.es/) on behalf of the Spanish Government. The main objective of the research Project is to monitor the CO2 migration within the reservoir during and after the injection as well as testing and evaluating different EM monitoring methods. In this way, a good characterization of the zone is imperative to perceive and quantify, as soon as possible, any change owing to the CO2 injection. Among all geophysical techniques, electrical and electromagnetic methods are especially useful and meaningful to monitor the CO2 plume since these methods are sensitive to the electrical conductivity of the pore fluid. The presence of CO2 inside the pore will replace a fraction of saline fluid within the storage aquifer, reducing the effective volume available for ionic transport. As a consequence, the bulk electrical resistivity of the rock is expected to increase significantly. The proposed EM techniques are the following: 1- Magnetotelluric method, 2-Cross-hole electrical resistivity tomography, 3- Control source electromagnetics. Moreover laboratory experiments are being carried out to monitor the CO2 flux inside sample cores using ERT.

  12. Monitoring arrangement for vented nuclear fuel elements

    DOEpatents

    Campana, Robert J.

    1981-01-01

    In a nuclear fuel reactor core, fuel elements are arranged in a closely packed hexagonal configuration, each fuel element having diametrically opposed vents permitting 180.degree. rotation of the fuel elements to counteract bowing. A grid plate engages the fuel elements and forms passages for communicating sets of three, four or six individual vents with respective monitor lines in order to communicate vented radioactive gases from the fuel elements to suitable monitor means in a manner readily permitting detection of leakage in individual fuel elements.

  13. Final Progress Report: Direct Experiments on the Ocean Disposal of Fossil Fuel CO2.

    SciTech Connect

    James P. Barry; Peter G. Brewer

    2004-05-25

    OAK-B135 This report summarizes activities and results of investigations of the potential environmental consequences of direct injection of carbon dioxide into the deep-sea as a carbon sequestration method. Results of field experiments using small scale in situ releases of liquid CO2 are described in detail. The major conclusions of these experiments are that mortality rates of deep sea biota will vary depending on the concentrations of CO2 in deep ocean waters that result from a carbon sequestration project. Large changes in seawater acidity and carbon dioxide content near CO2 release sites will likely cause significant harm to deep-sea marine life. Smaller changes in seawater chemistry at greater distances from release sites will be less harmful, but may result in significant ecosystem changes.

  14. Multi-species monitoring for fugitive gases and CO2 leakage at enhanced oil recovery operations

    NASA Astrophysics Data System (ADS)

    Risk, D. A.; Lavoie, M.; Brooks, B.; Goeckede, M.; Phillips, C. L.

    2013-12-01

    Carbon, Capture, and Storage (CCS) remains an option for reducing fossil CO2 emissions, but public acceptance continues to limit the roll-out of new projects. Monitoring is one mechanism by which operators can demonstrate credibility, competency, and environmental performance. While many previous research initiatives on surface monitoring have focused largely on soil gas sampling and geochemistries, fewer have tackled site-scale atmospheric detection techniques. This study aims to develop suitable techniques for identifying produced fluid leaks from wells and fugitive emissions from other associated infrastructure, and also to understand the variability of the target gases across land use types, and through time. During the growing season of 2013, we conducted multi-species atmospheric surveys of a 100 square kilometre Enhanced Oil Recovery site, using stationary and vehicle-mounted Cavity Ringdown Spectrometers (CRDS) targeting CH4, δ13C-CH4, CO2, and H2S. The study site offered excellent opportunity to study anthropogenic emissions, as it had well over 1000 active wells onsite, spatially distributed pipeline infrastructure, geochemical differentiation among the various possible emission sources, and also a road network that provided good access to most areas of the site. Leak detection using this method presented challenges related to the atmospheric transport modelling needed to back-calculate the source regions for observed anomalies. Transport models are generally not readily applicable at these smaller scales, so we developed an operational leak detection package. This package included the in situ and roving measurements, interpreted using simple mathematical models, maps, and remote sensing data, to narrow our survey search window and score sub-domains based on the gases present and the probability that these gases were man-made (as opposed to natural), in addition to the likely nature of the anthropogenic source as indicated by gas mixing ratios. Both

  15. Seasonal variations in δ13C and δ18O of atmospheric CO2 measured in the urban boundary layer over Vancouver, Canada in relation to fuel emissions.

    NASA Astrophysics Data System (ADS)

    Lee, J.; Christen, A.; Ketler, R.; Nesic, Z.; Schwendenmann, L.; Semmens, C.

    2014-12-01

    Recent advances in techniques to measure carbon dioxide (CO2) in urban plumes show potential for validating and monitoring emission inventories at regional to urban scale. A major challenge remains the attribution of elevated CO2 in urban plumes to different fuel and biogenic sources. Stable isotopes are a promising source of additional information. Here, we report a full year of measurements of CO2 mixing ratios, δ13C and δ18O in CO2 in the urban boundary layer over Vancouver, Canada. The goal of the work is to link seasonally changing isotopic composition to dominant fuel sources and put the urban enhancement into the context of regional background concentrations. Atmospheric composition in the urban atmosphere was measured continuously using a tunable diode laser absorption system (TGA 200, Campbell Scientific, Logan, UT, USA). In addition, end member signatures were determined by means of bag samples from representative fuel emission sources (gasoline, diesel, natural gas). While δ13C depends on the fuel type and origin (for Vancouver in 2013/14: δ13C gasoline 27.2‰; diesel -28.8‰; natural gas -41.6‰), δ18O is fractionated in catalytic converters (d18O gasoline vehicles -12.5‰; diesel -18.6‰; natural gas -22.7‰) and exhibits higher variability between samples. Additional signatures were determined for human, soil and plant respiration. During the study year, monthly mean mixing ratios in the urban atmosphere ranged between 410.5 (Jul) and 425.7 ppm (Dec), which was on average 18 ppm elevated above the regional background. As expected, mean monthly δ13C was lower in winter than summer with seasonally changing intercepts between -33.6‰ (JJF) and -27.7‰ (MJJ). Making the simple assumption that natural gas and gasoline are the only major fuel sources, natural gas would contribute ~45% to emissions in winter and ~3% in early summer, which is lower than the downscaled Local Emissions Inventory (57% in winter and 20% in summer). Mean δ18O showed

  16. Soda-fuel metallurgy: Metal ions for carbon neutral CO2 and H2O reduction

    NASA Astrophysics Data System (ADS)

    Neelameggham, Neale R.

    2009-04-01

    The role of minerals in biomass formation is understood only to a limited extent. When the term “photosynthesis—CO2 and H2O reduction of sugars, using solar energy”—is used, one normally thinks of chlorophyll as a compound containing magnesium. Alkali and alkaline earth metals present in leaf cells in the form of ions are equally essential in this solar energy bioconversion coupled with nitrogen fixation. Application of some of these principles can lead to artificial carbon-neutral processes on an industrial scale close to the concentrated CO2 emission sources.

  17. Delta13C values of grasses as a novel indicator of pollution by fossil-fuel-derived greenhouse gas CO2 in urban areas.

    PubMed

    Lichtfouse, Eric; Lichtfouse, Michel; Jaffrézic, Anne

    2003-01-01

    A novel fossil fuel pollution indicator based on the 13C/12C isotopic composition of plants has been designed. This bioindicator is a promising tool for future mapping of the sequestration of fossil fuel CO2 into urban vegetation. Theoretically, plants growing in fossil-fuel-CO2-contaminated areas, such as major cities, industrial centers, and highway borders, should assimilate a mixture of global atmospheric CO2 of delta13C value of -8.02 per thousand and of fossil fuel CO2 of average delta13C value of -27.28 per thousand. This isotopic difference should, thus, be recorded in plant carbon. Indeed, this study reveals that grasses growing near a major highway in Paris, France, have strikingly depleted delta13C values, averaging at -35.08 per thousand, versus rural grasses that show an average delta13C value of -30.59 per thousand. A simple mixing model was used to calculate the contributions of fossil-fuel-derived CO2 to the plant tissue. Calculation based on contaminated and noncontaminated isotopic end members shows that urban grasses assimilate up to 29.1% of fossil-fuel-CO2-derived carbon in their tissues. The 13C isotopic composition of grasses thus represents a promising new tool for the study of the impact of fossil fuel CO2 in major cities.

  18. Development of a low cost and low power consumption system for monitoring CO_{2} soil concentration in volcanic areas.

    NASA Astrophysics Data System (ADS)

    Awadallah Estévez, Shadia; Moure-García, David; Torres-González, Pedro; Acosta Sánchez, Leopoldo; Domínguez Cerdeña, Itahiza

    2017-04-01

    Volatiles dissolved in magma are released as gases when pressure or stress conditions change. H2O, CO2, SO2 and H2S are the most abundant gases involved in volcanic processes. Emission rates are related to changes in the volcanic activity. Therefore, in order to predict possible eruptive events, periodic measurements of CO2 concentrations from the soil should be carried out. In the last years, CO2 monitoring has been widespread for many reasons. A direct relationship between changes in volcanic activity and variations in concentration, diffuse flux and isotope ratios of this gas, have been observed prior to some eruptions or unrest processes. All these factors have pointed out the fact that CO2 emission data are crucial in volcanic monitoring programs. In addition, relevant instrumentation development has also taken place: improved accuracy, cost reduction and portability. Considering this, we propose a low cost and a low power consumption system for measuring CO2 concentration in the soil based on Arduino. Through a perforated pick-axe buried at a certain depth, gas samples are periodically taken with the aid of a piston. These samples are injected through a pneumatic circuit in the spectrometer, which measures the CO2 concentration. Simultaneously, the system records the following meteorological parameters: atmospheric pressure, precipitation, relative humidity and air and soil temperature. These parameters are used to correct their possible influence in the CO2 soil concentration. Data are locally stored (SD card) and transmitted via GPRS or WIFI to a data analysis center.

  19. Acoustic emission monitoring of hydraulic fracturing laboratory experiment with supercritical and liquid CO2

    NASA Astrophysics Data System (ADS)

    Ishida, Tsuyoshi; Aoyagi, Kazuhei; Niwa, Tomoya; Chen, Youqing; Murata, Sumihiko; Chen, Qu; Nakayama, Yoshiki

    2012-08-01

    Carbon dioxide (CO2) is often used for enhanced oil recovery in depleted petroleum reservoirs, and its behavior in rock is also of interest in CO2 capture and storage projects. CO2 usually becomes supercritical (SC-CO2) at depths greater than 1,000 m, while it is liquid (L-CO2) at low temperatures. The viscosity of L-CO2 is one order lower than that of normal liquid water, and that of SC-CO2 is much lower still. To clarify fracture behavior induced with injection of the low viscosity fluids, we conducted hydraulic fracturing experiments using 17 cm cubic granite blocks. The AE sources with the SC- and L-CO2 injections tend to distribute in a larger area than those with water injection, and furthermore, SC-CO2 tended to generate cracks extending more three dimensionally rather than along a flat plane than L-CO2. It was also found that the breakdown pressures for SC- and L-CO2 injections are expected to be considerably lower than for water.

  20. Applying monitoring, verification, and accounting techniques to a real-world, enhanced oil recovery operational CO2 leak

    USGS Publications Warehouse

    Wimmer, B.T.; Krapac, I.G.; Locke, R.; Iranmanesh, A.

    2011-01-01

    The use of carbon dioxide (CO2) for enhanced oil recovery (EOR) is being tested for oil fields in the Illinois Basin, USA. While this technology has shown promise for improving oil production, it has raised some issues about the safety of CO2 injection and storage. The Midwest Geological Sequestration Consortium (MGSC) organized a Monitoring, Verification, and Accounting (MVA) team to develop and deploy monitoring programs at three EOR sites in Illinois, Indiana, and Kentucky, USA. MVA goals include establishing baseline conditions to evaluate potential impacts from CO2 injection, demonstrating that project activities are protective of human health and the environment, and providing an accurate accounting of stored CO2. This paper focuses on the use of MVA techniques in monitoring a small CO2 leak from a supply line at an EOR facility under real-world conditions. The ability of shallow monitoring techniques to detect and quantify a CO2 leak under real-world conditions has been largely unproven. In July of 2009, a leak in the pipe supplying pressurized CO2 to an injection well was observed at an MGSC EOR site located in west-central Kentucky. Carbon dioxide was escaping from the supply pipe located approximately 1 m underground. The leak was discovered visually by site personnel and injection was halted immediately. At its largest extent, the hole created by the leak was approximately 1.9 m long by 1.7 m wide and 0.7 m deep in the land surface. This circumstance provided an excellent opportunity to evaluate the performance of several monitoring techniques including soil CO2 flux measurements, portable infrared gas analysis, thermal infrared imagery, and aerial hyperspectral imagery. Valuable experience was gained during this effort. Lessons learned included determining 1) hyperspectral imagery was not effective in detecting this relatively small, short-term CO2 leak, 2) even though injection was halted, the leak remained dynamic and presented a safety risk concern

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

    PubMed

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

    2014-10-21

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

  2. Direct conversion of CO2 into liquid fuels with high selectivity over a bifunctional catalyst

    NASA Astrophysics Data System (ADS)

    Gao, Peng; Li, Shenggang; Bu, Xianni; Dang, Shanshan; Liu, Ziyu; Wang, Hui; Zhong, Liangshu; Qiu, Minghuang; Yang, Chengguang; Cai, Jun; Wei, Wei; Sun, Yuhan

    2017-10-01

    Although considerable progress has been made in carbon dioxide (CO2) hydrogenation to various C1 chemicals, it is still a great challenge to synthesize value-added products with two or more carbons, such as gasoline, directly from CO2 because of the extreme inertness of CO2 and a high C-C coupling barrier. Here we present a bifunctional catalyst composed of reducible indium oxides (In2O3) and zeolites that yields a high selectivity to gasoline-range hydrocarbons (78.6%) with a very low methane selectivity (1%). The oxygen vacancies on the In2O3 surfaces activate CO2 and hydrogen to form methanol, and C‑C coupling subsequently occurs inside zeolite pores to produce gasoline-range hydrocarbons with a high octane number. The proximity of these two components plays a crucial role in suppressing the undesired reverse water gas shift reaction and giving a high selectivity for gasoline-range hydrocarbons. Moreover, the pellet catalyst exhibits a much better performance during an industry-relevant test, which suggests promising prospects for industrial applications.

  3. China: Emissions pattern of the world leader in CO2 emissions from fossil fuel consumption and cement production

    NASA Astrophysics Data System (ADS)

    Gregg, Jay S.; Andres, Robert J.; Marland, Gregg

    2008-04-01

    Release of carbon dioxide (CO2) from fossil fuel combustion and cement manufacture is the primary anthropogenic driver of climate change. Our best estimate is that China became the largest national source of CO2 emissions during 2006. Previously, the United States (US) had occupied that position. However, the annual emission rate in the US has remained relatively stable between 2001-2006 while the emission rate in China has more than doubled, apparently eclipsing that of the US in late 2006. Here we present the seasonal and spatial pattern of CO2 emissions in China, as well as the sectoral breakdown of emissions. Though our best point estimate places China in the lead position in terms of CO2 emissions, we qualify this statement in a discussion of the uncertainty in the underlying data (3-5% for the US; 15-20% for China). Finally, we comment briefly on the implications of China's new position with respect to international agreements to mitigate climate change.

  4. Photocatalytic conversion of CO(2) into renewable hydrocarbon fuels: state-of-the-art accomplishment, challenges, and prospects.

    PubMed

    Tu, Wenguang; Zhou, Yong; Zou, Zhigang

    2014-07-16

    Photocatalytic reduction of CO2 into hydrocarbon fuels, an artificial photosynthesis, is based on the simulation of natural photosynthesis in green plants, whereby O2 and carbohydrates are produced from H2 O and CO2 using sunlight as an energy source. It couples the reductive half-reaction of CO2 fixation with a matched oxidative half-reaction such as water oxidation, to achieve a carbon neutral cycle, which is like killing two birds with one stone in terms of saving the environment and supplying future energy. The present review provides an overview and highlights recent state-of-the-art accomplishments of overcoming the drawback of low photoconversion efficiency and selectivity through the design of highly active photocatalysts from the point of adsorption of reactants, charge separation and transport, light harvesting, and CO2 activation. It specifically includes: i) band-structure engineering, ii) nanostructuralization, iii) surface oxygen vacancy engineering, iv) macro-/meso-/microporous structuralization, v) exposed facet engineering, vi) co-catalysts, vii) the development of a Z-scheme system. The challenges and prospects for future development of this field are also present. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Leaf-architectured 3D Hierarchical Artificial Photosynthetic System of Perovskite Titanates Towards CO2 Photoreduction Into Hydrocarbon Fuels

    NASA Astrophysics Data System (ADS)

    Zhou, Han; Guo, Jianjun; Li, Peng; Fan, Tongxiang; Zhang, Di; Ye, Jinhua

    2013-04-01

    The development of an ``artificial photosynthetic system'' (APS) having both the analogous important structural elements and reaction features of photosynthesis to achieve solar-driven water splitting and CO2 reduction is highly challenging. Here, we demonstrate a design strategy for a promising 3D APS architecture as an efficient mass flow/light harvesting network relying on the morphological replacement of a concept prototype-leaf's 3D architecture into perovskite titanates for CO2 photoreduction into hydrocarbon fuels (CO and CH4). The process uses artificial sunlight as the energy source, water as an electron donor and CO2 as the carbon source, mimicking what real leaves do. To our knowledge this is the first example utilizing biological systems as ``architecture-directing agents'' for APS towards CO2 photoreduction, which hints at a more general principle for APS architectures with a great variety of optimized biological geometries. This research would have great significance for the potential realization of global carbon neutral cycle.

  6. Leaf-architectured 3D Hierarchical Artificial Photosynthetic System of Perovskite Titanates Towards CO2 Photoreduction Into Hydrocarbon Fuels

    PubMed Central

    Zhou, Han; Guo, Jianjun; Li, Peng; Fan, Tongxiang; Zhang, Di; Ye, Jinhua

    2013-01-01

    The development of an “artificial photosynthetic system” (APS) having both the analogous important structural elements and reaction features of photosynthesis to achieve solar-driven water splitting and CO2 reduction is highly challenging. Here, we demonstrate a design strategy for a promising 3D APS architecture as an efficient mass flow/light harvesting network relying on the morphological replacement of a concept prototype-leaf's 3D architecture into perovskite titanates for CO2 photoreduction into hydrocarbon fuels (CO and CH4). The process uses artificial sunlight as the energy source, water as an electron donor and CO2 as the carbon source, mimicking what real leaves do. To our knowledge this is the first example utilizing biological systems as “architecture-directing agents” for APS towards CO2 photoreduction, which hints at a more general principle for APS architectures with a great variety of optimized biological geometries. This research would have great significance for the potential realization of global carbon neutral cycle. PMID:23588925

  7. 40 CFR 600.008 - Review of fuel economy, CO2 emissions, and carbon-related exhaust emission data, testing by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 31 2013-07-01 2013-07-01 false Review of fuel economy, CO2 emissions... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES General Provisions § 600.008 Review of fuel economy,...

  8. 40 CFR 600.206-12 - Calculation and use of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... in addition to miles per gasoline gallon equivalent, and fuel cell vehicles will determine miles per... HFET-based fuel economy, CO2 emissions, and carbon-related exhaust emission values for vehicle... (CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Procedures...

  9. 40 CFR 600.206-12 - Calculation and use of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... in addition to miles per gasoline gallon equivalent, and fuel cell vehicles will determine miles per... HFET-based fuel economy, CO2 emissions, and carbon-related exhaust emission values for vehicle... (CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Procedures...

  10. 40 CFR 600.206-12 - Calculation and use of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... in addition to miles per gasoline gallon equivalent, and fuel cell vehicles will determine miles per... HFET-based fuel economy, CO2 emissions, and carbon-related exhaust emission values for vehicle... (CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Procedures...

  11. Climate Change to the Nuclear Fuel Cycle: Expanding the spectral (14)CO(2) database for non-AMS Field Measurement Systems

    NASA Astrophysics Data System (ADS)

    Marino, B. D. V.; Odonnell, R. G.; Tolliver, D. E.

    2014-06-01

    Accelerator Mass Spectrometry (AMS) is well known and universally employed for radiocarbon analysis but is not adaptable to in-situ field measurements limiting applications. 14CO2 is a key tracer for fossil fuel CO2 as well as for release of enriched 14CO2 characteristic of the nuclear fuel cycle with ∆14CO2 values ranging from -1000 to ˜+500 per mil. However, to exploit the full value of in situ 14CO2 data in diverse climate change and nuclear fuel cycle applications, high data rate temporal and spatial field measurement sensors and systems are required. The development of non-AMS methods based on quantum cascade laser, cavity ring down and optogalvanic spectroscopy are emerging applications but not fully developed for field use or widely accepted. Spectral data for lasing transitions for 14CO2 are lacking in contrast to HITRAN data available for 12CO2 (626) and 13CO2 (636) (among other isotopologues 628, 638, etc.) in the spectral databases limiting development and innovation in non-AMS 14CO2 sensors and systems. We review the corpus of 14CO2 spectral data available in the literature and document grating tuned isotopic lasers (e.g., Freed 19901; Bradley et al., 19862), well suited for expanded spectral studies of 14CO2 and inclusion in the HITRAN database. Non-AMS 14CO2 approaches are reviewed with suggestions for future work to support field systems for 14CO2 measurements. Available isotopic lasers for 14CO2 collaborative studies are described.

  12. Testing surface gas monitoring methods at sites of natural and man-made CO2 seepage in Europe

    NASA Astrophysics Data System (ADS)

    Jones, D.; Lister, R.; Barkwith, A.; Barlow, T.; Shaw, R.; Strutt, M.; Lombardi, S.; Beaubien, S.; Annunziatellis, A.; Graziani, S.

    2011-12-01

    Useful lessons for monitoring techniques and strategies can be learned at natural CO2 seepage sites. Existing methods and new developments can be tested at such sites to assess how useful they would be at geological CO2 storage sites. Such testing is not possible at actual storage sites where there is no leakage. Experience has been gained at the natural CO2 seepage sites near Latera in Italy, the Laacher See in Germany and Florina in Greece. Studies have also been carried out at experimental CO2 injection sites in the UK and Norway and at landfill sites in the UK. The sites have been used as a testing ground for existing and new techniques including open path lasers, eddy covariance, CO2 monitoring stations, flux chambers and in situ and laboratory soil gas analysis. Natural CO2 seepage at the sites tends to occur at gas vents of restricted surface extent. Typically such vents have a diameter of metres to tens of metres. Whilst the vents may align along faults or fractures they occur at small discrete points on such features where permeability is higher. These appear commonly to be associated with fracture intersections. Venting therefore occurs over only a small fraction of the total area of the sites. By analogy this suggests that a surface monitoring strategy for a CO2 storage site needs to include cost effective screening methods that can cover large areas quickly but which are capable of finding small leakage targets. Soil gas concentrations and fluxes vary with time in response to factors such as temperature, pressure, wind speed and soil moisture. This gives rise to diurnal, seasonal and weather system related cycles. Seepage of CO2 can therefore vary over time and this implies the need for continuous monitoring techniques to avoid missing transient releases. Developing legislation for CO2 storage sites (such as the European Union Storage Directive) also requires the quantification of any detected CO2 leakage and this will require an understanding of

  13. Distributions of fossil fuel originated CO2 in five metropolitan areas of Korea (Seoul, Busan, Daegu, Daejeon, and Gwangju) according to the Δ14C in ginkgo leaves

    NASA Astrophysics Data System (ADS)

    Park, J. H.; Hong, W.; Park, G.; Sung, K. S.; Lee, K. H.; Kim, Y. E.; Kim, J. K.; Choi, H. W.; Kim, G. D.; Woo, H. J.

    2013-01-01

    We collected a batch of ginkgo (Ginkgo biloba Linnaeus) leaf samples at five metropolitan areas of Korea (Seoul, Busan, Daegu, Daejeon, and Gwangju) in 2009 to obtain the regional distribution of fossil fuel originated CO2 (fossil fuel CO2) in the atmosphere. Regions assumed to be free of fossil fuel CO2 were also selected, namely Mt. Chiak, Mt. Kyeryong, Mt. Jiri, Anmyeon Island, and Jeju Island and ginkgo leaf samples were collected in those areas during the same period. The Δ14C values of the samples were measured using Accelerator Mass Spectrometry (AMS) and the fossil fuel CO2 ratios in the atmosphere were obtained in the five metropolitan areas. The average ratio of fossil fuel CO2 in Seoul was higher than that in the other four cities. The leaves from the Sajik Tunnel in Seoul recorded the highest FFCTC (fossil fuel CO2 over total CO2 in atmosphere), 13.9 ± 0.5%, as the air flow of the surrounding neighborhood of the Sajik Tunnel was blocked.

  14. Monitoring CO2 concentration and δ13C in an underground cavity using a commercial isotope ratio infrared spectrometer

    NASA Astrophysics Data System (ADS)

    Guillon, Sophie; Agrinier, Pierre; Pili, Éric

    2015-04-01

    CO2 stable carbon isotopes are very attractive in environmental research to investigate both natural and anthropogenic carbon sources. Laser-based isotope ratio infrared spectrometers (IRIS) allow in situ continuous monitoring of CO2 isotopes, and therefore they have a potential for unprecedented understanding of carbon sources and dynamics with a high temporal resolution. Here we present the performance assessment of a commercial IRIS analyzer, including the measurement setup and the data processing scheme that we used. Even if the analyzer performs 1-Hz measurements, an integration time of the order of 1 h is commonly needed to obtain acceptable precision for δ13C. The main sources of uncertainty on δ13C come from the concentration dependence and from the temporal instability of the analyzer. The method is applied to the in situ monitoring of the CO2 carbon isotopes in an underground cavity (Roselend Natural Laboratory, France) during several months. On a weekly timescale, the temporal variability of CO2 is dominated by transient contamination by human breath. Discarding these anthropogenic contaminations, CO2 and δ13C backgrounds do not show diurnal or seasonal fluctuations. A CO2 flux released into the tunnel by the surrounding rocks is measured. The carbon isotope composition of this CO2, identified with a Keeling plot, is consistent with a main production by microbial respiration and a minor production from weathering of carbonate minerals. The presented instrument and application study are relevant to cave monitoring, whether to understand CO2 dynamics in visited and/or painted caves for preservation purposes or to understand paleoclimate recording in speleothems.

  15. Periodic behavior of soil CO2 emissions in diffuse degassing areas of the Azores archipelago: Application to seismovolcanic monitoring

    NASA Astrophysics Data System (ADS)

    Viveiros, Fátima; Vandemeulebrouck, Jean; Rinaldi, Antonio P.; Ferreira, Teresa; Silva, Catarina; Cruz, José V.

    2014-10-01

    Time series of soil CO2 efflux recorded in the Azores archipelago volcanic-hydrothermal areas feature daily and seasonal variations. The recorded CO2 efflux values were lower during summer than in the winter season. The diurnal CO2 efflux values were higher at dawn and lower in the early afternoon, contrary to that observed in biogenic environments. CO2 efflux cycles correlated well with the environmental variables, such as air temperature, wind speed, and barometric pressure, which also showed low- and high-frequency periodicities. Several simulations were performed here using the Transport of Unsaturated Groundwater and Heat 2 (TOUGH2) geothermal simulator to complement the study of Rinaldi et al. (2012). The effects of the water table depth, air temperature perturbation amplitude, and soil thermal gradient contributed to an explanation of the contrasts observed in the diurnal (S1) and semidiurnal (S2) soil CO2 efflux peaks for the different monitoring sites and seasons. Filtering techniques (multivariate regression analysis and fast Fourier transform filters) were also applied to the recorded time series to remove effects of external variables on the soil CO2 efflux. The resulting time series (the residuals) correspond to the best approach to the deep-seated (volcanic/hydrothermal) CO2 emissions and thus should be used in seismovolcanic monitoring programs. Even if no evident correlation can be established yet between the soil CO2 residuals and seismicity over the monitored time, a seismic swarm that occurred around the end of 2008 might have triggered some deviations from the observed daily cycles.

  16. Seismic monitoring results from the first 6 months of CO2 injection at the Aquistore geological storage site, Saskatchewan, Canada

    NASA Astrophysics Data System (ADS)

    Daley, T. M.; White, D. J.; Stork, A.; Schmitt, D. R.; Worth, K.; Harris, K.; Roberts, B.; Samson, C.; Kendal, M. J.

    2015-12-01

    The Aquistore Project, located in SE Saskatchewan, Canada, is a demonstration project for CO2 storage in a deep saline aquifer. CO2 captured from a nearby coal-fired power plant is being injected into a brine-filled sandstone formation at 3100-3300 m depth. CO2 injection commenced in April, 2015, at initial rates of up to 250 tonnes per day. Seismic monitoring methods have been employed to track the subsurface CO2 plume and to record any injection-induced microseismicity. Active seismic methods utilized include 4D surface seismics using a sparse permanent array, 4D vertical seismic profiles (VSP) with both downhole geophones and a fiber optic distributed acoustic sensor (DAS) system. Pre-injection baseline seismic surveys have established very good repeatability with NRMS values as low as 0.07. 3D finite-difference seismic modelling of fluid flow simulations is used with the repeatability estimates to determine the appropriate timing for the first CO2 monitor surveys. Time-lapse logging is being conducted on a regular basis to provide in situ measurement of the change in seismic velocity associated with changes in CO2 saturation. Continuous passive seismic recording has been ongoing since the summer of 2012 to establish background local seismicity prior to the start of CO2 injection. Passive monitoring is being conducted using two, 2.5 km long, orthogonal linear arrays of surface geophones.with 3-component short-period geophones, 3 broadband surface seismometers, and an array of 3-component short-period geophones in an observation well. No significant injection-related seismicity (Mw > -1) has been detected at the surface during the first 4 months of CO2 injection. On-going analysis of the downhole passive data will provide further information as to the occurrence of lower magnitude microseismicity (Mw of -1 to -3).

  17. Fuel cell stack monitoring and system control

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2004-02-17

    A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell.

  18. Risk Assessment and Monitoring of Stored CO2 in Organic Rocks Under Non-Equilibrium Conditions

    SciTech Connect

    Malhotra, Vivak

    2014-06-30

    The USA is embarking upon tackling the serious environmental challenges posed to the world by greenhouse gases, especially carbon dioxide (CO2). The dimension of the problem is daunting. In fact, according to the Energy Information Agency, nearly 6 billion metric tons of CO2 were produced in the USA in 2007 with coal-burning power plants contributing about 2 billion metric tons. To mitigate the concerns associated with CO2 emission, geological sequestration holds promise. Among the potential geological storage sites, unmineable coal seams and shale formations in particular show promise because of the probability of methane recovery while sequestering the CO2. However. the success of large-scale sequestration of CO2 in coal and shale would hinge on a thorough understanding of CO2's interactions with host reservoirs. An important parameter for successful storage of CO2 reservoirs would be whether the pressurized CO2 would remain invariant in coal and shale formations under reasonable internal and/or external perturbations. Recent research has brought to the fore the potential of induced seismicity, which may result in caprock compromise. Therefore, to evaluate the potential risks involved in sequestering CO2 in Illinois bituminous coal seams and shale, we studied: (i) the mechanical behavior of Murphysboro (Illinois) and Houchin Creek (Illinois) coals, (ii) thermodynamic behavior of Illinois bituminous coal at - 100oC ≤ T ≤ 300oC, (iii) how high pressure CO2 (up to 20.7 MPa) modifies the viscosity of the host, (iv) the rate of emission of CO2 from Illinois bituminous coal and shale cores if the cores, which were pressurized with high pressure (≤ 20.7 MPa) CO2, were exposed to an atmospheric pressure, simulating the development of leakage pathways, (v) whether there are any fractions of CO2 stored in these hosts which are resistance to emission by simply exposing the cores to atmospheric pressure, and (vi) how compressive shockwaves applied to the coal and shale

  19. Integration & Co-development of a Geophysical CO2 Monitoring Suite

    SciTech Connect

    Friedmann, S J

    2007-07-24

    Carbon capture and sequestration (CCS) has emerged as a key technology for dramatic short-term reduction in greenhouse gas emissions in particular from large stationary. A key challenge in this arena is the monitoring and verification (M&V) of CO2 plumes in the deep subsurface. Towards that end, we have developed a tool that can simultaneously invert multiple sub-surface data sets to constrain the location, geometry, and saturation of subsurface CO2 plumes. We have focused on a suite of unconventional geophysical approaches that measure changes in electrical properties (electrical resistance tomography, electromagnetic induction tomography) and bulk crustal deformation (til-meters). We had also used constraints of the geology as rendered in a shared earth model (ShEM) and of the injection (e.g., total injected CO{sub 2}). We describe a stochastic inversion method for mapping subsurface regions where CO{sub 2} saturation is changing. The technique combines prior information with measurements of injected CO{sub 2} volume, reservoir deformation and electrical resistivity. Bayesian inference and a Metropolis simulation algorithm form the basis for this approach. The method can (a) jointly reconstruct disparate data types such as surface or subsurface tilt, electrical resistivity, and injected CO{sub 2} volume measurements, (b) provide quantitative measures of the result uncertainty, (c) identify competing models when the available data are insufficient to definitively identify a single optimal model and (d) rank the alternative models based on how well they fit available data. We present results from general simulations of a hypothetical case derived from a real site. We also apply the technique to a field in Wyoming, where measurements collected during CO{sub 2} injection for enhanced oil recovery serve to illustrate the method's performance. The stochastic inversions provide estimates of the most probable location, shape, volume of the plume and most likely CO{sub 2

  20. Monitoring underground migration of sequestered CO2 using self-potential methods

    NASA Astrophysics Data System (ADS)

    Ishido, T.; Pritchett, J.; Tosha, T.; Nishi, Y.; Nakanishi, S.

    2013-12-01

    An appropriate monitoring program is indispensable for an individual geologic storage project to aid in answering various operational questions by detecting changes within the reservoir and to provide early warning of potential CO2 leakage through the caprock. Such a program is also essential to reduce uncertainties associated with reservoir parameters and to improve the predictive capability of reservoir models. Repeat geophysical measurements performed at the earth surface show particular promise for monitoring large subsurface volumes. To appraise the utility of geophysical techniques, Ishido et al. carried out numerical simulations of an aquifer system underlying a portion of Tokyo Bay and calculated the temporal changes in geophysical observables caused by changing underground conditions as computed by reservoir simulation (Energy Procedia, 2011). They used 'geophysical postprocessors' to calculate the resulting temporal changes in the earth-surface distributions of microgravity, self-potential (SP), apparent resistivity (from MT surveys) and seismic observables. The applicability of any particular method is likely to be highly site-specific, but these calculations indicate that none of these techniques should be ruled out altogether. Some survey techniques (gravity, MT resistivity) appear to be suitable for characterizing long-term changes, whereas others (seismic reflection, SP) are quite responsive to short term disturbances. The self-potential postprocessor calculates changes in subsurface electrical potential induced by pressure disturbances through electrokinetic coupling (Ishido & Pritchett, JGR 1999). In addition to electrokinetic coupling, SP anomalies may be generated by various other mechanisms such as thermoelectric coupling, electrochemical diffusion potential, etc. In particular, SP anomalies of negative polarity, which are frequently observed near wells, appear to be caused by an underground electrochemical mechanism similar to a galvanic cell

  1. Surrogate gas prediction model as a proxy for Δ(14)C-based measurements of fossil fuel-CO2.

    PubMed

    Coakley, Kevin J; Miller, John B; Montzka, Stephen A; Sweeney, Colm; Miller, Ben R

    2016-06-27

    The measured (14)C:(12)C isotopic ratio of atmospheric CO2 (and its associated derived Δ(14)C value) is an ideal tracer for determination of the fossil fuel derived CO2 enhancement contributing to any atmospheric CO2 measurement (Cff ). Given enough such measurements, independent top-down estimation of US fossil fuel-CO2 emissions should be possible. However, the number of Δ(14)C measurements is presently constrained by cost, available sample volume, and availability of mass spectrometer measurement facilities. Δ(14)C is therefore measured in just a small fraction of samples obtained by ask air sampling networks around the world. Here, we develop a Projection Pursuit Regression (PPR) model to predict Cff as a function of multiple surrogate gases acquired within the NOAA/ESRL Global Greenhouse Gas Reference Network (GGGRN). The surrogates consist of measured enhancements of various anthropogenic trace gases, including CO, SF6, and halo- and hydrocarbons acquired in vertical airborne sampling profiles near Cape May, NJ and Portsmouth, NH from 2005 through 2010. Model performance for these sites is quantified based on predicted values corresponding to test data excluded from the model building process. Chi-square hypothesis test analysis indicates that these predictions and corresponding observations are consistent given our uncertainty budget which accounts for random effects and one particular systematic effect. However, quantification of the combined uncertainty of the prediction due to all relevant systematic effects is difficult because of the limited range of the observations and their relatively high fractional uncertainties at the sampling sites considered here. To account for the possibility of additional systematic effects, we incorporate another component of uncertainty into our budget. Expanding the number of Δ(14)C measurements in the NOAA GGGRN and building new PPR models at additional sites would improve our understanding of uncertainties and

  2. Surrogate gas prediction model as a proxy for Δ14C-based measurements of fossil fuel CO2

    NASA Astrophysics Data System (ADS)

    Coakley, Kevin J.; Miller, John B.; Montzka, Stephen A.; Sweeney, Colm; Miller, Ben R.

    2016-06-01

    The measured 14C:12C isotopic ratio of atmospheric CO2 (and its associated derived Δ14C value) is an ideal tracer for determination of the fossil fuel derived CO2 enhancement contributing to any atmospheric CO2 measurement (Cff). Given enough such measurements, independent top-down estimation of U.S. fossil fuel CO2 emissions should be possible. However, the number of Δ14C measurements is presently constrained by cost, available sample volume, and availability of mass spectrometer measurement facilities. Δ14C is therefore measured in just a small fraction of samples obtained by flask air sampling networks around the world. Here we develop a projection pursuit regression (PPR) model to predict Cff as a function of multiple surrogate gases acquired within the NOAA/Earth System Research Laboratory (ESRL) Global Greenhouse Gas Reference Network (GGGRN). The surrogates consist of measured enhancements of various anthropogenic trace gases, including CO, SF6, and halocarbon and hydrocarbon acquired in vertical airborne sampling profiles near Cape May, NJ and Portsmouth, NH from 2005 to 2010. Model performance for these sites is quantified based on predicted values corresponding to test data excluded from the model building process. Chi-square hypothesis test analysis indicates that these predictions and corresponding observations are consistent given our uncertainty budget which accounts for random effects and one particular systematic effect. However, quantification of the combined uncertainty of the prediction due to all relevant systematic effects is difficult because of the limited range of the observations and their relatively high fractional uncertainties at the sampling sites considered here. To account for the possibility of additional systematic effects, we incorporate another component of uncertainty into our budget. Expanding the number of Δ14C measurements in the NOAA GGGRN and building new PPR models at additional sites would improve our understanding of

  3. Photocatalytic reduction of CO2 into hydrocarbon solar fuels over g-C3N4-Pt nanocomposite photocatalysts.

    PubMed

    Yu, Jiaguo; Wang, Ke; Xiao, Wei; Cheng, Bei

    2014-06-21

    Photocatalytic reduction of CO2 into renewable hydrocarbon fuels is an alternative way to develop reproducible energy, which is also a promising way to solve the problem of the greenhouse effect. In this work, graphitic carbon nitride (g-C3N4) was synthesized by directly heating thiourea at 550 °C and then a certain amount of Pt was deposited on it to form g-C3N4-Pt nanocomposites used as catalysts for photocatalytic reduction of CO2 under simulated solar irradiation. The main products of photocatalysis were CH4, CH3OH and HCHO. The deposited Pt acted as an effective cocatalyst, which not only influenced the selectivity of the product generation, but also affected the activity of the reaction. The yield of CH4 first increased upon increasing the amount of Pt deposited on the g-C3N4 from 0 to 1 wt%, then decreased at 2 wt% Pt loading. The production rates of CH3OH and HCHO also increased with the content of Pt increasing from 0 to 0.75 wt% and the maximum yield was observed at 0.75 wt%. The Pt nanoparticles (NPs) could facilitate the transfer and enrichment of photogenerated electrons from g-C3N4 to its surface for photocatalytic reduction of CO2. At the same time, Pt was also used a catalyst to promote the oxidation of products. The transient photocurrent response further confirmed the proposed photocatalytic reduction mechanism of CO2. This work indicates that the deposition of Pt is a good strategy to improve the photoactivity and selectivity of g-C3N4 for CO2 reduction.

  4. Anion-Exchange Membrane Fuel Cells with Improved CO2 Tolerance: Impact of Chemically Induced Bicarbonate Ion Consumption.

    PubMed

    Katayama, Yu; Yamauchi, Kosuke; Hayashi, Kohei; Okanishi, Takeou; Muroyama, Hiroki; Matsui, Toshiaki; Kikkawa, Yuuki; Negishi, Takayuki; Watanabe, Shin; Isomura, Takenori; Eguchi, Koichi

    2017-08-30

    Over the last few decades, because of the significant development of anion exchange membranes, increasing efforts have been devoted the realization of anion exchange membrane fuel cells (AEMFCs) that operate with the supply of hydrogen generated on-site. In this paper, ammonia was selected as a hydrogen source, following which the effect of conceivable impurities, unreacted NH3 and atmospheric CO2, on the performance of AEMFCs was established. As expected, we show that these impurities worsen the performance of AEMFCs significantly. Furthermore, with the help of in situ attenuated total reflection infrared (ATR-IR) spectroscopy, it was revealed that the degradation of the cell performance was primarily due to the inhibition of the hydrogen oxidation reaction (HOR). This is attributed to the active site occupation by CO-related adspecies derived from (bi)carbonate adspecies. Interestingly, this degradation in the HOR activity is suppressed in the presence of both NH3 and HCO3(-) because of the bicarbonate ion consumption reaction induced by the existence of NH3. Further analysis using in situ ATR-IR and electrochemical methods revealed that the poisonous CO-related adspecies were completely removed under NH3-HCO3(-) conditions, accompanied by the improvement in HOR activity. Finally, a fuel cell test was conducted by using the practical AEMFC with the supply of NH3-contained H2 gas to the anode and ambient air to the cathode. The result confirmed the validity of this positive effect of NH3-HCO3(-) coexistence on CO2-tolerence of AEMFCs. The cell performance achieved nearly 95% of that without any impurity in the fuels. These results clearly show the impact of the chemically induced bicarbonate ion consumption reaction on the realization of highly CO2-tolerent AEMFCs.

  5. The kinetics of the O2/CO2 reaction in molten carbonate - Reaction orders for O2 and CO2 on NiO. [in fuel cells

    NASA Technical Reports Server (NTRS)

    Winnick, J.; Ross, P. N.

    1980-01-01

    The kinetics of the O2/CO2 reaction in molten carbonate is investigated using paste electrolytes and nickel sinter electrodes. A two-step approach to the determination of reaction orders is employed. First, exchange currents at various P(CO2) and P(O2) were measured using the low polarization method. Second, alpha(+) and alpha(-) values were obtained from the slope of the Allen-Hickling plot for current densities low enough so that concentration polarization within the electrode can be neglected. The reaction orders are + 1/4 in CO2 and + 5/8 in O2 in the cathodic direction, and - 3/4 in CO2 and + 1/8 in O2 in the anodic direction.

  6. A 10-year record of geochemical and isotopic monitoring at the IEA Weyburn-Midale CO2 Monitoring and Storage Project (Saskatchewan, Canada)

    NASA Astrophysics Data System (ADS)

    Mayer, Bernhard; Shevalier, Maurice; Nightingale, Michael; Kwon, Jang-Soon; Hutcheon, Ian

    2013-04-01

    Carbon capture and storage is a promising technology to reduce CO2 emissions into the atmosphere. Monitoring of CO2 storage sites is required by many of the emerging regulations with specific interest in verification of injected CO2 in various target reservoirs. The objective of this study was to use geochemical and isotopic techniques to trace the fate of CO2 injected over a 10-year period at the IEA Weyburn-Midale CO2 Monitoring and Storage Project (Saskatchewan, Canada). Geochemical monitoring measures changes in chemical and isotopic parameters of fluid and gas samples in a storage reservoir due to brine-mineral-CO2 reactions resulting from CO2 injection. Seventeen sampling events were conducted over a 10-year period, including one pre-injection (baseline in the year 2000) and 16 post-injection surveys between 2001 and 2010. Fluid and gas samples were obtained from circa 50 observation wells per sampling event followed by chemical and isotope analyses. Carbon isotope ratios (δ13C) of injected CO2 were constant at -20.4 ‰ throughout the 10-year study period and were markedly different from baseline δ13C values of dissolved CO2 in the reservoir brines. Therefore, carbon isotope ratio measurements constitute an elegant tool for tracing the movement and the geochemical fate of injected CO2 in the reservoir. Gas samples obtained from the observation wells at baseline had a median CO2 concentration of 4 mole%. After 7 to 10 years of CO2 injection, a significant increase in the median CO2 concentration was observed yielding values ranging from 64 to 75 mole%. This increase in CO2 concentrations was accompanied by a decrease in the δ13C values of CO2 from a median value of -12.7 ‰ at baseline in the year 2000 to values near -18 ‰ between 2008 and 2010. This is evidence that elevated CO2 concentrations are caused by injected CO2 arriving at numerous observation wells. Analyses of fluid samples revealed that the median total alkalinity increased from ~400 mg

  7. Monitoring CO2 intrusion and associated geochemical transformations in a shallow groundwater system using complex electrical methods.

    PubMed

    Dafflon, Baptiste; Wu, Yuxin; Hubbard, Susan S; Birkholzer, Jens T; Daley, Thomas M; Pugh, John D; Peterson, John E; Trautz, Robert C

    2013-01-02

    The risk of CO(2) leakage from a properly permitted deep geologic storage facility is expected to be very low. However, if leakage occurs it could potentially impact potable groundwater quality. Dissolved CO(2) in groundwater decreases pH, which can mobilize naturally occurring trace metals commonly contained in aquifer sediments. Observing such processes requires adequate monitoring strategies. Here, we use laboratory and field experiments to explore the sensitivity of time-lapse complex resistivity responses for remotely monitoring dissolved CO(2) distribution and geochemical transformations that may impact groundwater quality. Results show that electrical resistivity and phase responses correlate well with dissolved CO(2) injection processes. Specifically, resistivity initially decreases due to increase of bicarbonate and dissolved species. As pH continues to decrease, the resistivity rebounds toward initial conditions due to the transition of bicarbonate into nondissociated carbonic acid, which reduces the total concentration of dissociated species and thus the water conductivity. An electrical phase decrease is also observed, which is interpreted to be driven by the decrease of surface charge density as well as potential mineral dissolution and ion exchange. Both laboratory and field experiments demonstrate the potential of field complex resistivity method for remotely monitoring changes in groundwater quality due to CO(2) leakage.

  8. Response of CO2 Concentration in Andisol to Rainfall Events by Using Buried Tubing Gas Monitoring System

    NASA Astrophysics Data System (ADS)

    Endo, Toshifumi; Tokida, Takeshi; Imoto, Hiromi; Nishimura, Taku; Miyazaki, Tsuyoshi

    For the purpose of continuous soil CO2 gas monitoring, gas permeable resins were evaluated. Among polytetrafluoroethylen (PTFE), polyfluoroethylene propylene (PFEP) and silicone, the silicone rubber tube had highest permeability for oxygen gas. Buried Tubing Gas Monitoring System (BT-GMS) consisting of silicone rubber tube connected to a Non-diffuse infrared (NDIR) -CO2 gas and galvanic cell O2 gas sensors were constructed, and buried into an Andisol upland field at a depth of 20cm. Thermo-couples and EC-5 soil moisture sensors were inserted into 10 and 20cm deep layers. Soil CO2 gas concentration, temperature and moisture were continuously monitored for 5 months. Soil CO2 concentration was sensitive to rainfall events and soil moisture change. Responses were keen during summer until early autumn when soil temperature was higher than 20°C. Then, when soil temperature got lower the response tended to be dull. This suggested quick CO2 gas concentration change following a rainfall event was mostly due to enhancement in soil respiration with soil moisture rise.

  9. Atmospheric CO2 Concentrations from Aircraft for 1972-1981, CSIRO Monitoring Program

    DOE Data Explorer

    Beardsmore, D. J.; Pearman, G. I.

    2012-01-01

    From 1972 through 1981, air samples were collected in glass flasks from aircraft at a variety of latitudes and altitudes over Australia, New Zealand, and Antarctica. The samples were analyzed for CO2 concentrations with nondispersive infrared gas analysis. The resulting data contain the sampling dates, type of aircraft, flight number, flask identification number, sampling time, geographic sector, distance in kilometers from the listed distance measuring equipment (DME) station, station number of the radio navigation distance measuring equipment, altitude of the aircraft above mean sea level, sample analysis date, flask pressure, tertiary standards used for the analysis, analyzer used, and CO2 concentration. These data represent the first published record of CO2 concentrations in the Southern Hemisphere expressed in the WMO 1981 CO2 Calibration Scale and provide a precise record of atmospheric CO2 concentrations in the troposphere and lower stratosphere over Australia and New Zealand.

  10. Open framework metal chalcogenides as efficient photocatalysts for reduction of CO2 into renewable hydrocarbon fuel.

    PubMed

    Sasan, Koroush; Lin, Qipu; Mao, Chengyu; Feng, Pingyun

    2016-06-07

    Open framework metal chalcogenides are a family of porous semiconducting materials with diverse chemical compositions. Here we show that these materials containing covalent three-dimensional superlattices of nanosized supertetrahedral clusters can function as efficient photocatalysts for the reduction of CO2 to CH4. Unlike dense semiconductors, metal cations are successfully incorporated into the channels of the porous semiconducting materials to further tune the physical properties of the materials such as electrical conductivity and band gaps. In terms of the photocatalytic properties, the metal-incorporated porous chalcogenides demonstrated enhanced solar energy absorption and higher electrical conductivity and improved photocatalytic activity.

  11. An Integrated Hydrogen Production-CO2 Capture Process from Fossil Fuel

    SciTech Connect

    Z. Wang; K. B. Bota

    2005-03-15

    The major project objective is to determine the feasibility of using the char from coal and/or biomass pyrolysis, ammonia and CO2 emissions at smokestacks to produce clean hydrogen and a sequestered carbon fertilizer. During this work period, literature review has been completed. The project plan, design and test schedules were made on the basis of discussion with partner in experimental issues. Installation of pilot scale units was finished and major units tests were fully performed. Modification of the pyrolyzer, reformer and gas absorption tank have been done. Integration testing is performing recently. Lab scale tests are in operation phase. The experimental installations are discussed in this paper.

  12. Effect of fossil fuels on the parameters of CO2 capture.

    PubMed

    Nagy, Tibor; Mizsey, Peter

    2013-08-06

    The carbon dioxide capture is a more and more important issue in the design and operation of boilers and/or power stations because of increasing environmental considerations. Such processes, absorber desorber should be able to cope with flue gases from the use of different fossil primary energy sources, in order to guarantee a flexible, stable, and secure energy supply operation. The changing flue gases have significant influence on the optimal operation of the capture process, that is, where the required heating of the desorber is the minimal. Therefore special considerations are devoted to the proper design and control of such boiler and/or power stations equipped with CO2 capture process.

  13. An Intergrated Hydrogen Production-CO2 Capture Process from Fossil Fuel

    SciTech Connect

    Z. Wang; K. B. Bota

    2006-03-15

    The major project objective is to determine the feasibility of using the char from coal and/or biomass pyrolysis, ammonia and CO2 emissions at smokestacks to produce clean hydrogen and a sequestered carbon fertilizer. During this work period, the project plan, design and test schedules were made on the basis of discussion with partner in experimental issues. Installation of pilot scale units was finished and major units tests were fully performed. Modification of the pyrolyzer, reformer and gas absorption tank have been done. Integration testing is performing recently. Lab scale tests have been performed. Field tests of char/fertilizer have been conducted.

  14. CO2 emissions mitigation and fossil fuel markets: Dynamic and international aspects of climate policies

    SciTech Connect

    Bauer, Nico; Bosetti, Valentina; Hamdi-Cherif, Meriem; Kitous, Alban; McCollum, David; Mejean, Aurelie; Rao, Shilpa; Turton, Hal; Paroussos, Leonidas; Ashina, Shuichi; Calvin, Katherine V.; Wada, Kenichi; Van Vuuren, Detlef

    2015-01-01

    This paper explores a multi-model scenario ensemble to assess the impacts of idealized and non-idealized climate change stabilization policies on fossil fuel markets. Under idealized conditions climate policies significantly reduce coal use in the short- and long-term. Reductions in oil and gas use are much smaller, particularly until 2030, but revenues decrease much more because oil and gas prices are higher and decrease with mitigation. A first deviation from the optimal transition pathway relaxes global emission targets until 2030, in accordance with the Copenhagen pledges and regionally-specific low-carbon technology targets. Fossil fuel markets revert back to the no-policy case: though coal use increases strongest, revenue gains are higher for oil and gas. To balance the carbon budget over the 21st century, the long-term reallocation of fossil fuels is significantly larger - twice and more - than the short-term distortion. This amplifying effect results from coal lock-in and inter-fuel substitution effects. The second deviation from the optimal transition pathway relaxes the global participation assumption. The result here is less clear cut across models, as we find carbon leakage effects ranging from positive to negative because leakage and substitution patterns of coal, oil, and gas differ. In summary, distortions of fossil fuel markets resulting from relaxed short-term global emission targets are more important and less uncertain than the issue of carbon leakage from early mover action.

  15. Toward quantification and source sector identification of fossil fuel CO2 emissions from an urban area: Results from the INFLUX experiment

    NASA Astrophysics Data System (ADS)

    Turnbull, Jocelyn C.; Sweeney, Colm; Karion, Anna; Newberger, Timothy; Lehman, Scott J.; Tans, Pieter P.; Davis, Kenneth J.; Lauvaux, Thomas; Miles, Natasha L.; Richardson, Scott J.; Cambaliza, Maria Obiminda; Shepson, Paul B.; Gurney, Kevin; Patarasuk, Risa; Razlivanov, Igor

    2015-01-01

    Indianapolis Flux Experiment (INFLUX) aims to develop and assess methods for quantifying urban greenhouse gas emissions. Here we use CO2, 14CO2, and CO measurements from tall towers around Indianapolis, USA, to determine urban total CO2, the fossil fuel derived CO2 component (CO2ff), and CO enhancements relative to background measurements. When a local background directly upwind of the urban area is used, the wintertime total CO2 enhancement over Indianapolis can be entirely explained by urban CO2ff emissions. Conversely, when a continental background is used, CO2ff enhancements are larger and account for only half the total CO2 enhancement, effectively representing the combined CO2ff enhancement from Indianapolis and the wider region. In summer, we find that diurnal variability in both background CO2 mole fraction and covarying vertical mixing makes it difficult to use a simple upwind-downwind difference for a reliable determination of total CO2 urban enhancement. We use characteristic CO2ff source sector CO:CO2ff emission ratios to examine the contribution of the CO2ff source sectors to total CO2ff emissions. This method is strongly sensitive to the mobile sector, which produces most CO. We show that the inventory-based emission product ("bottom up") and atmospheric observations ("top down") can be directly compared throughout the diurnal cycle using this ratio method. For Indianapolis, the top-down observations are consistent with the bottom-up Hestia data product emission sector patterns for most of the diurnal cycle but disagree during the nighttime hours. Further examination of both the top-down and bottom-up assumptions is needed to assess the exact cause of the discrepancy.

  16. Evaluation of SF6, C2Cl4, and CO to approximate fossil fuel CO2 in the Northern Hemisphere using a chemistry transport model

    NASA Astrophysics Data System (ADS)

    Rivier, L.; Ciais, P.; Hauglustaine, D. A.; Bakwin, P.; Bousquet, P.; Peylin, P.; Klonecki, A.

    2006-08-01

    The distribution of the fossil fuel component in atmospheric CO2 cannot be measured directly at a cheap cost. Could anthropogenic tracers with source patterns similar to fossil fuel CO2 then be used for that purpose? Here we present and evaluate a methodology using surrogate tracers, CO, SF6, and C2Cl4, to deduce fossil fuel CO2. A three-dimensional atmospheric chemistry transport model is used to simulate the relationship between each tracer and fossil fuel CO2. In summertime the regression slopes between fossil fuel CO2 and surrogate tracers show large spatial variations for chemically active tracers (CO and C2Cl4), although C2Cl4 presents less scatter than CO. At two tall tower sites in the United States (WLEF, Wisconsin, and WITN, North Carolina), we found that in summertime the C2Cl4 (CO) versus fossil CO2 slope is on average up to 15% (25%) higher than in winter. We show that for C2Cl4 this seasonal variation is due to OH oxidation. For CO the seasonal variation is due to both chemistry and mixing with nonanthropogenic CO sources. In wintertime the three surrogate tracers SF6, C2Cl4, and CO are about equally as good indicators of the presence of fossil CO2. However, our model strongly underestimates the variability of SF6 at both towers, probably because of unaccounted for emissions. Hence poor knowledge of emission distribution hampers the use of SF6 as a surrogate tracer. From a practical point of view we recommend the use of C2Cl4 as a proxy of fossil CO2. We also recommend the use of tracers to separate fossil CO2. Despite the fact that the uncertainty on the regression slope is on the order of 30%, the tracer approach is likely to have less bias than when letting one model with one inventory emission map calculate the fossil CO2 distribution.

  17. Fuel cell stack monitoring and system control

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2005-01-25

    A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell. Other polarization curves may be generated and used for fuel cell stack monitoring based on different operating pressures, temperatures, hydrogen quantities.

  18. COPROCESSING OF FOSSIL FUELS AND BIOMASS FOR CO2 EMISSION REDUCTION IN THE TRANSPORTATION SECTOR

    EPA Science Inventory

    The paper discusses an evaluation of the Hydrocarb process for conversion of carbonaceous raw material to clean carbon and methanol products. As fuel, methanol and carbon can be used economically, either independently or in slurry form, in efficient heat engines (turbines and int...

  19. COPROCESSING OF FOSSIL FUELS AND BIOMASS FOR CO2 EMISSION REDUCTION IN THE TRANSPORTATION SECTOR

    EPA Science Inventory

    The paper discusses an evaluation of the Hydrocarb process for conversion of carbonaceous raw material to clean carbon and methanol products. As fuel, methanol and carbon can be used economically, either independently or in slurry form, in efficient heat engines (turbines and int...

  20. Monitoring gaseous CO2 and ethanol above champagne glasses: flute versus coupe, and the role of temperature.

    PubMed

    Liger-Belair, Gérard; Bourget, Marielle; Pron, Hervé; Polidori, Guillaume; Cilindre, Clara

    2012-01-01

    In champagne tasting, gaseous CO(2) and volatile organic compounds progressively invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Simultaneous quantification of gaseous CO(2) and ethanol was monitored through micro-gas chromatography (μGC), all along the first 15 minutes following pouring, depending on whether a volume of 100 mL of champagne was served into a flute or into a coupe. The concentration of gaseous CO(2) was found to be significantly higher above the flute than above the coupe. Moreover, a recently developed gaseous CO(2) visualization technique based on infrared imaging was performed, thus confirming this tendency. The influence of champagne temperature was also tested. As could have been expected, lowering the temperature of champagne was found to decrease ethanol vapor concentrations in the headspace of a glass. Nevertheless, and quite surprisingly, this temperature decrease had no impact on the level of gaseous CO(2) found above the glass. Those results were discussed on the basis of a multiparameter model which describes fluxes of gaseous CO(2) escaping the liquid phase into the form of bubbles.

  1. Monitoring Gaseous CO2 and Ethanol above Champagne Glasses: Flute versus Coupe, and the Role of Temperature

    PubMed Central

    Liger-Belair, Gérard; Bourget, Marielle; Pron, Hervé; Polidori, Guillaume; Cilindre, Clara

    2012-01-01

    In champagne tasting, gaseous CO2 and volatile organic compounds progressively invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Simultaneous quantification of gaseous CO2 and ethanol was monitored through micro-gas chromatography (μGC), all along the first 15 minutes following pouring, depending on whether a volume of 100 mL of champagne was served into a flute or into a coupe. The concentration of gaseous CO2 was found to be significantly higher above the flute than above the coupe. Moreover, a recently developed gaseous CO2 visualization technique based on infrared imaging was performed, thus confirming this tendency. The influence of champagne temperature was also tested. As could have been expected, lowering the temperature of champagne was found to decrease ethanol vapor concentrations in the headspace of a glass. Nevertheless, and quite surprisingly, this temperature decrease had no impact on the level of gaseous CO2 found above the glass. Those results were discussed on the basis of a multiparameter model which describes fluxes of gaseous CO2 escaping the liquid phase into the form of bubbles. PMID:22347390

  2. Towards space based verification of CO2 emissions from strong localized sources: fossil fuel power plant emissions as seen by a CarbonSat constellation

    NASA Astrophysics Data System (ADS)

    Velazco, V. A.; Buchwitz, M.; Bovensmann, H.; Reuter, M.; Schneising, O.; Heymann, J.; Krings, T.; Gerilowski, K.; Burrows, J. P.

    2011-08-01

    Carbon dioxide (CO2) is the most important man-made greenhouse gas (GHG) that cause global warming. With electricity generation through fossil-fuel power plants now as the economic sector with the largest source of CO2, power plant emissions monitoring has become more important than ever in the fight against global warming. In a previous study done by Bovensmann et al. (2010), random and systematic errors of power plant CO2 emissions have been quantified using a single overpass from a proposed CarbonSat instrument. In this study, we quantify errors of power plant annual emission estimates from a hypothetical CarbonSat and constellations of several CarbonSats while taking into account that power plant CO2 emissions are time-dependent. Our focus is on estimating systematic errors arising from the sparse temporal sampling as well as random errors that are primarily dependent on wind speeds. We used hourly emissions data from the US Environmental Protection Agency (EPA) combined with assimilated and re-analyzed meteorological fields from the National Centers of Environmental Prediction (NCEP). CarbonSat orbits were simulated as a sun-synchronous low-earth orbiting satellite (LEO) with an 828-km orbit height, local time ascending node (LTAN) of 13:30 (01:30 p.m.) and achieves global coverage after 5 days. We show, that despite the variability of the power plant emissions and the limited satellite overpasses, one CarbonSat can verify reported US annual CO2 emissions from large power plants (≥5 Mt CO2 yr-1) with a systematic error of less than ~4.9 % for 50 % of all the power plants. For 90 % of all the power plants, the systematic error was less than ~12.4 %. We additionally investigated two different satellite configurations using a combination of 5 CarbonSats. One achieves global coverage everyday but only samples the targets at fixed local times. The other configuration samples the targets five times at two-hour intervals approximately every 6th day but only

  3. Towards space based verification of CO2 emissions from strong localized sources: fossil fuel power plant emissions as seen by a CarbonSat constellation

    NASA Astrophysics Data System (ADS)

    Velazco, V. A.; Buchwitz, M.; Bovensmann, H.; Reuter, M.; Schneising, O.; Heymann, J.; Krings, T.; Gerilowski, K.; Burrows, J. P.

    2011-12-01

    Carbon dioxide (CO2) is the most important man-made greenhouse gas (GHG) that cause global warming. With electricity generation through fossil-fuel power plants now being the economic sector with the largest source of CO2, power plant emissions monitoring has become more important than ever in the fight against global warming. In a previous study done by Bovensmann et al. (2010), random and systematic errors of power plant CO2 emissions have been quantified using a single overpass from a proposed CarbonSat instrument. In this study, we quantify errors of power plant annual emission estimates from a hypothetical CarbonSat and constellations of several CarbonSats while taking into account that power plant CO2 emissions are time-dependent. Our focus is on estimating systematic errors arising from the sparse temporal sampling as well as random errors that are primarily dependent on wind speeds. We used hourly emissions data from the US Environmental Protection Agency (EPA) combined with assimilated and re-analyzed meteorological fields from the National Centers of Environmental Prediction (NCEP). CarbonSat orbits were simulated as a sun-synchronous low-earth orbiting satellite (LEO) with an 828-km orbit height, local time ascending node (LTAN) of 13:30 (01:30 p.m. LT) and achieves global coverage after 5 days. We show, that despite the variability of the power plant emissions and the limited satellite overpasses, one CarbonSat has the potential to verify reported US annual CO2 emissions from large power plants (≥5 Mt CO2 yr-1) with a systematic error of less than ~4.9% and a random error of less than ~6.7% for 50% of all the power plants. For 90% of all the power plants, the systematic error was less than ~12.4% and the random error was less than ~13%. We additionally investigated two different satellite configurations using a combination of 5 CarbonSats. One achieves global coverage everyday but only samples the targets at fixed local times. The other configuration

  4. The venous-arterial CO2 to arterial-venous O2 content difference ratio: Easy to monitor?

    PubMed

    Danin, Pierre Eric; Bendjelid, Karim

    2016-10-01

    Blood sampling for venous-arterial CO2 to arterial-venous O2 content difference ratio starts to be widely used as a hemodynamic monitoring tool, despite that this calculation remains cumbersome. We propose using indirect calorimetry and respiratory quotient for this purpose, with the same physiological concept. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Enhance performance of micro direct methanol fuel cell by in situ CO2 removal using novel anode flow field with superhydrophobic degassing channels

    NASA Astrophysics Data System (ADS)

    Liang, Junsheng; Luo, Ying; Zheng, Sheng; Wang, Dazhi

    2017-05-01

    Capillary blocking caused by CO2 bubbles in anode flow field (AFF) is one of the bottlenecks for performance improvement of a micro direct methanol fuel cell (μDMFC). In this work, we present a novel AFF structure with nested layout of hydrophilic fuel channels and superhydrophobic degassing channels which can remove most of CO2 from AFF before it is released to the fuel channels. The new AFFs are fabricated on Ti substrates by using micro photochemical etching combined with anodization and fluorination treatments. Performance of the μDMFCs with and without superhydrophobic degassing channels in their AFF is comparatively studied. Results show that the superhydrophobic degassing channels can significantly speed up the exhaust of CO2 from the AFF. CO2 clogging is not observed in the new AFFs even when their comparison AFFs have been seriously blocked by CO2 slugs under the same operating conditions. 55% and 60% of total CO2 produced in μDMFCs with N-serpentine and N-spiral AFF can be respectively removed by the superhydrophobic degassing channels. The power densities of the μDMFCs equipped with new serpentine and spiral AFFs are respectively improved by 30% and 90% compared with those using conventional AFFs. This means that the new AFFs developed in this work can effectively prevent CO2-induced capillary blocking in the fuel channels, and finally significantly improve the performance of the μDMFCs.

  6. An Integrated Hydrogen Producton-CO2 Capture Process from Fossil Fuel

    SciTech Connect

    Z. Wang; K.B. Bota; D. Day

    2005-12-01

    The major project objective is to determine the feasibility of using the char from coal and/or biomass pyrolysis, ammonia and CO2 emissions at smokestacks to produce clean hydrogen and a sequestered carbon fertilizer. During this work period, literature review has been completed. The project plan, design and test schedules were made on the basis of discussion with partner in experimental issues. Installation of pilot scale units was finished and major units tests were fully performed. Modification of the pyrolyzer, reformer and gas absorption tank have been done. Integration testing is performing recently. Lab scale tests have been performed. Field tests of char/fertilizer have been conducted. The experimental results are discussed in this paper.

  7. Soil CO2 efflux measurement network by means of closed static chambers to monitor volcanic activity at Tenerife, Canary Islands

    NASA Astrophysics Data System (ADS)

    Amonte, Cecilia; García-Merino, Marta; Asensio-Ramos, María; Melián, Gladys; García-Hernández, Rubén; Pérez, Aaron; Hernández, Pedro A.; Pérez, Nemesio M.

    2017-04-01

    Tenerife (2304 km2) is the largest of the Canary Islands and has developed a central volcanic complex (Cañadas edifice), that started to grow about 3.5 My ago. Coeval with the construction of the Cañadas edifice, shield basaltic volcanism continued until the present along three rift zones oriented NW-SE, NE-SW and NS (hereinafter referred as NW, NE and NS respectively). Main volcanic historical activity has occurred along de NW and NE rift-zones, although summit cone of Teide volcano, in central volcanic complex, is the only area of the island where surface geothermal manifestations are visible. Uprising of deep-seated gases occurs along the aforementioned volcanic structures causing diffuse emissions at the surface environment of the rift-zones. In the last 20 years, there has been considerable interest in the study of diffuse degassing as a powerful tool in volcano monitoring programs. Diffuse degassing studies are even more important volcanic surveillance tool at those volcanic areas where visible manifestations of volcanic gases are absent. Historically, soil gas and diffuse degassing surveys in volcanic environments have focused mainly on CO2 because it is, after water vapor, the most abundant gas dissolved in magma. One of the most popular methods used to determine CO2 fluxes in soil sciences is based on the absorption of CO2 through an alkaline medium, in its solid or liquid form, followed by gravimetric, conductivity, or titration analyses. In the summer of 2016, a network of 31 closed static chambers was installed, covering the three main structural zones of Tenerife (NE, NW and NS) as well as Cañadas Caldera with volcanic surveillance porpoises. 50 cc of 0.1N KOH solution is placed inside the chamber to absorb the CO2 released from the soil. The solution is replaced weekly and the trapped CO2 is then analyzed at the laboratory by titration. The are expressed as weekly integrated CO2 efflux values. The CO2 efflux values ranged from 3.2 to 12.9 gṡm-2

  8. Seventeen years of monitoring diffuse CO2 emission from the Tenerife North-West Rift Zone (NWRZ) volcano, Canary Islands

    NASA Astrophysics Data System (ADS)

    Padilla, Germán D.; Evans, Bethany J.; Provis, Aaron R.; Asensio, María; Alonso, Mar; Calvo, David; Hernández, Pedro; Pérez, Nemesio M.

    2017-04-01

    Tenerife together and Gran Canaria are the central islands of the Canarian archipelago, which have developed a central volcanic complex characterized by the eruption of differentiated magmas. Tenerife is the largest of the Canary Islands (2100 km2) and at present, the North-West Rift-Zone (NWRZ) is one of the most active volcanic structures of the three volcanic rift-zone of the island, which has hosted two historical eruptions (Arenas Negras in 1706 and Chinyero in 1909). In order to monitor the volcanic activity of NWRZ, since the year 2000, 49 soil CO2 efflux surveys have been performed at NWRZ (more than 300 observation sites each one) to evaluate the temporal an spatial variations of CO2 efflux and their relationships with the volcanic-seismic activity. Measurements were performed in accordance with the accumulation chamber method. Spatial distribution maps were constructed following the sequential Gaussian simulation (sGs) procedure. To quantify the total CO2 emission from the studied area, 100 simulations for each survey have been performed. We report herein the results of the last diffuse CO2 efflux surveys at the NWRZ undertaken in July and October 2016 to constrain the total CO2 output from the studied area. During July and October 2016 surveys, soil CO2 efflux values ranged from non-detectable up to 32.4 and 53.7 g m-2 d-1, respectively. The total diffuse CO2 output released to atmosphere were estimated at 255 ± 9 and 338 ± 18 t d-1, respectively, values higher than the background CO2 emission estimated on 144 t d-1. Since 2000, soil CO2 efflux values have ranged from non-detectable up to 141 g m-2 d-1, with the highest values measured in May 2005 whereas total CO2 output ranged between 52 and 867 t d-1. Long-term variations in the total CO2 output have shown a temporal correlation with the onsets of seismic activity at Tenerife, supporting unrest of the volcanic system, as is also suggested by anomalous seismic activity recorded in the studied area

  9. The Potential for Increased Atmospheric CO2 Emissions and Accelerated Consumption of Deep Geologic CO2 Storage Resources Resulting from the Large-Scale Deployment of a CCS-Enabled Unconventional Fossil Fuels Industry in the U.S.

    SciTech Connect

    Dooley, James J.; Dahowski, Robert T.; Davidson, Casie L.

    2009-11-02

    Desires to enhance the energy security of the United States have spurred significant interest in the development of abundant domestic heavy hydrocarbon resources including oil shale and coal to produce unconventional liquid fuels to supplement conventional oil supplies. However, the production processes for these unconventional fossil fuels create large quantities of carbon dioxide (CO2) and this remains one of the key arguments against such development. Carbon dioxide capture and storage (CCS) technologies could reduce these emissions and preliminary analysis of regional CO2 storage capacity in locations where such facilities might be sited within the U.S. indicates that there appears to be sufficient storage capacity, primarily in deep saline formations, to accommodate the CO2 from these industries. Nevertheless, even assuming wide-scale availability of cost-effective CO2 capture and geologic storage resources, the emergence of a domestic U.S. oil shale or coal-to-liquids (CTL) industry would be responsible for significant increases in CO2 emissions to the atmosphere. The authors present modeling results of two future hypothetical climate policy scenarios that indicate that the oil shale production facilities required to produce 3MMB/d from the Eocene Green River Formation of the western U.S. using an in situ retorting process would result in net emissions to the atmosphere of between 3000-7000 MtCO2, in addition to storing potentially 900-5000 MtCO2 in regional deep geologic formations via CCS in the period up to 2050. A similarly sized, but geographically more dispersed domestic CTL industry could result in 4000-5000 MtCO2 emitted to the atmosphere in addition to potentially 21,000-22,000 MtCO2 stored in regional deep geologic formations over the same period. While this analysis shows that there is likely adequate CO2 storage capacity in the regions where these technologies are likely to deploy, the reliance by these industries on large-scale CCS could result

  10. Safe storage and effective monitoring of CO2 in depleted gas fields.

    PubMed

    Jenkins, Charles R; Cook, Peter J; Ennis-King, Jonathan; Undershultz, James; Boreham, Chris; Dance, Tess; de Caritat, Patrice; Etheridge, David M; Freifeld, Barry M; Hortle, Allison; Kirste, Dirk; Paterson, Lincoln; Pevzner, Roman; Schacht, Ulrike; Sharma, Sandeep; Stalker, Linda; Urosevic, Milovan

    2012-01-10

    Carbon capture and storage (CCS) is vital to reduce CO(2) emissions to the atmosphere, potentially providing 20% of the needed reductions in global emissions. Research and demonstration projects are important to increase scientific understanding of CCS, and making processes and results widely available helps to reduce public concerns, which may otherwise block this technology. The Otway Project has provided verification of the underlying science of CO(2) storage in a depleted gas field, and shows that the support of all stakeholders can be earned and retained. Quantitative verification of long-term storage has been demonstrated. A direct measurement of storage efficiency has been made, confirming that CO(2) storage in depleted gas fields can be safe and effective, and that these structures could store globally significant amounts of CO(2).

  11. CO2 Sparging Phase 3 Full Scale Implementation and Monitoring Report

    EPA Pesticide Factsheets

    In-situ carbon dioxide (CO2) sparging was designed and implemented to treat a subsurface causticbrine pool (CBP) formed as a result of releases from historical production of industrial chemicals at theLCP Chemicals Site, Brunswick, GA (Site).

  12. Active CO2 Reservoir Management for Carbon Capture, Utilization, and Sequestration: Impact on Permitting, Monitoring, and Public Acceptance

    NASA Astrophysics Data System (ADS)

    Buscheck, T. A.; Chen, M.; Sun, Y.; Hao, Y.; Court, B.; Celia, M. A.; Wolery, T.; Aines, R. D.

    2011-12-01

    CO2 capture and sequestration (CCS) integrated with geothermal energy production in deep geological formations can play an important role in reducing CO2 emissions to the atmosphere and thereby mitigate global climate change. For industrial-scale CO2 injection in saline formations, pressure buildup can limit storage capacity and security. Active CO2 Reservoir Management (ACRM) combines brine production with CO2 injection to relieve pressure buildup, increase injectivity, manipulate CO2 migration, constrain brine leakage, and enable beneficial utilization of produced brine. Therefore, ACRM can be an enabler of carbon capture, utilization, and sequestration (CCUS). Useful products may include freshwater, cooling water, make-up water for pressure support in oil, gas, and geothermal reservoir operations, and geothermal energy production. Implementation barriers to industrial-scale CCS include concerns about (1) CO2 sequestration security and assurance, (2) pore-space competition with neighboring subsurface activities, (3) CO2 capture costs, and (4) water-use demands imposed by CCS operations, which is particularly important where water resources are already scarce. CCUS, enabled by ACRM, has the potential of addressing these barriers. Pressure relief from brine production can substantially reduce the driving force for potential CO2 and brine migration, as well as minimize interference with neighboring subsurface activities. Electricity generated from geothermal energy can offset a portion of the parasitic energy and financial costs of CCS. Produced brine can be used to generate freshwater by desalination technologies, such as RO, provide a source for saltwater cooling systems or be used as make-up water for oil, gas, or geothermal reservoir operations, reducing the consumption of valuable freshwater resources. We examine the impact of brine production on reducing CO2 and brine leakage. A volumetric balance between injected and produced fluids minimizes the spatial

  13. A Sea Floor Gravity Survey of the Sleipner Field to Monitor CO2 Migration

    SciTech Connect

    Mark Zumberge

    2011-09-30

    Carbon dioxide gas (CO{sub 2}) is a byproduct of many wells that produce natural gas. Frequently the CO{sub 2} separated from the valuable fossil fuel gas is released into the atmosphere. This adds to the growing problem of the climatic consequences of greenhouse gas contamination. In the Sleipner North Sea natural gas production facility, the separated CO{sub 2} is injected into an underground saline aquifer to be forever sequestered. Monitoring the fate of such sequestered material is important - and difficult. Local change in Earth's gravity field over the injected gas is one way to detect the CO{sub 2} and track its migration within the reservoir over time. The density of the injected gas is less than that of the brine that becomes displaced from the pore space of the formation, leading to slight but detectable decrease in gravity observed on the seafloor above the reservoir. Using equipment developed at Scripps Institution of Oceanography, we have been monitoring gravity over the Sleipner CO{sub 2} sequestration reservoir since 2002. We surveyed the field in 2009 in a project jointly funded by a consortium of European oil and gas companies and the US Department of Energy. The value of gravity at some 30 benchmarks on the seafloor, emplaced at the beginning of the monitoring project, was observed in a week-long survey with a remotely operated vehicle. Three gravity meters were deployed on the benchmarks multiple times in a campaign-style survey, and the measured gravity values compared to those collected in earlier surveys. A clear signature in the map of gravity differences is well correlated with repeated seismic surveys.

  14. Detection and monitoring of H2O and CO2 ice clouds on Mars

    USGS Publications Warehouse

    Bell, J.F.; Calvin, W.M.; Ockert-Bell, M. E.; Crisp, D.; Pollack, James B.; Spencer, J.

    1996-01-01

    We have developed an observational scheme for the detection and discrimination of Mars atmospheric H2O and CO2 clouds using ground-based instruments in the near infrared. We report the results of our cloud detection and characterization study using Mars near IR images obtained during the 1990 and 1993 oppositions. We focused on specific wavelengths that have the potential, based on previous laboratory studies of H2O and CO2 ices, of yielding the greatest degree of cloud detectability and compositional discriminability. We have detected and mapped absorption features at some of these wavelengths in both the northern and southern polar regions of Mars. Compositional information on the nature of these absorption features was derived from comparisons with laboratory ice spectra and with a simplified radiative transfer model of a CO2 ice cloud overlying a bright surface. Our results indicate that both H2O and CO2 ices can be detected and distinguished in the polar hood clouds. The region near 3.00 ??m is most useful for the detection of water ice clouds because there is a strong H2O ice absorption at this wavelength but only a weak CO2 ice band. The region near 3.33 ??m is most useful for the detection of CO2 ice clouds because there is a strong, relatively narrow CO2 ice band at this wavelength but only broad "continuum" H2O ice absorption. Weaker features near 2.30 ??m could arise from CO2 ice at coarse grain sizes, or surface/dust minerals. Narrow features near 2.00 ??m, which could potentially be very diagnostic of CO2 ice clouds, suffer from contamination by Mars atmospheric CO2 absorptions and are difficult to interpret because of the rather poor knowledge of surface elevation at high latitudes. These results indicate that future ground-based, Earth-orbital, and spacecraft studies over a more extended span of the seasonal cycle should yield substantial information on the style and timing of volatile transport on Mars, as well as a more detailed understanding of

  15. Sixteen years monitoring of Cumbre Vieja volcano (La Palma, Canary Islands) by means of diffuse CO2 degassing surveys

    NASA Astrophysics Data System (ADS)

    Cótchico, M. A.; Renee, L. K.; De Jongh, M. E.; Padron, E.; Hernandez Perez, P. A.; Perez, N. M.

    2016-12-01

    La Palma Island, the fifth longest (706 km2) and second highest (2,423 m asl) of the Canary Islands, is located at the northwestern end of the archipelago. Subaerial volcanic activity on La Palma started 2.0 My ago and has taken place exclusively at the southern part of the island during the last 123 ka, where Cumbre Vieja volcano, the most active basaltic volcano in the Canaries, has been constructed. Major volcano-structural and geomorphological features of Cumbre Vieja volcano are a north-south rift zone 20 km long, with vents located also at the northwest and northeast, and up to 1,950 m in elevation covering an área of 220 km2. Nowadays, there are no visible gas emissions from fumaroles or hot springs at Cumbre Vieja; therefore, diffuse CO2 degassing monitoring is important geochemical tool for its volcanic surveillance. Recent studies have shown that enhanced endogenous contributions of deep-seated CO2 might have been responsible for higher diffuse CO2 efflux values (Padrón et al., 2015). We report here the latest results of the diffuse CO2 emission survey at Cumbre Vieja volcano. The surface CO2 efflux measurements were taken using the accumulation chamber method in the period 1997- 2016 to evaluate their spatial distribution on this 220 km2 volcano and the diffuse CO2 emission rate from Cumbre Vieja volcano. Surface CO2 efflux values ranged from non-detectable up to 94 g m-2 d-1 in the last survey. Spatial distribution maps were constructed following the sequential Gaussian simulation (sGs) procedure. The spatial distribution of diffuse CO2 emission values did not seem to be controlled by the main structural features of the volcano since the highest values were measured in the southern part. The diffuse CO2 emission for the 2016 survey has been estimated about 739 ± 30 t d-1. The 2016 emission rate is slightly higher than the estimated average for Cumbre Vieja volcano (493 t d-1), but within the observed background range for this volcanic system over the

  16. Reduction of CO2 Emissions from Mobile Sources by Alternative Fuels Derived from Biomass.

    DTIC Science & Technology

    1993-11-01

    those goals with alcohol fuels derived from biomass produced as short-rotation woody crops. Emphasis is on the Hydrocarb process , now under evaluation...that a process such as Hydrocarb, that can leverage biomass with natural gas, should maximize petroleum displacement at least cost. Because of these...on the Hydrocarb process , now under evaluation by the EPA for production of methanol from biomass and natural gas. Factors considered in this

  17. Integration of an Emerging Highly Sensitive Optical CO2 Sensor for Ocean Monitoring on an Existing Data Acquisition System SeaKeeper 1000 (trademark)

    DTIC Science & Technology

    2012-09-30

    be deployed in geat numbers to autonomously monitor the overall patterns of CO2 emissions and ocean acidification . OBJECTIVES  Meet the...Integration of an Emerging Highly Sensitive Optical CO2 Sensor for Ocean Monitoring on an Existing Data Acquisition System SeaKeeper 1000TM Annual...challenging requirements for ocean pCO2 monitoring using an innovative sensor design based on high sensitivity fluorescence detection.  Assemble the system

  18. Integration of an Emerging Highly Sensitive Optical CO2 Sensor for Ocean Monitoring on an Existing Data Acquisition System SeaKeeper 1000(TM)

    DTIC Science & Technology

    2011-09-30

    be deployed in geat numbers to autonomously monitor the overall patterns of CO2 emissions and ocean acidification . OBJECTIVES  Meet the...Integration of an Emerging Highly Sensitive Optical CO2 Sensor for Ocean Monitoring on an Existing Data Acquisition System SeaKeeper 1000TM Annual...challenging requirements for ocean pCO2 monitoring using an innovative sensor design based on high sensitivity fluorescence detection.  Assemble the system

  19. Quantifying the Observability of CO2 Flux Uncertainty in Atmospheric CO2 Records Using Products from Nasa's Carbon Monitoring Flux Pilot Project

    NASA Technical Reports Server (NTRS)

    Ott, Lesley; Pawson, Steven; Collatz, Jim; Watson, Gregg; Menemenlis, Dimitris; Brix, Holger; Rousseaux, Cecile; Bowman, Kevin; Bowman, Kevin; Liu, Junjie; Eldering, Annmarie; Gunson, Michael; Kawa, Stephan R.

    2014-01-01

    NASAs Carbon Monitoring System (CMS) Flux Pilot Project (FPP) was designed to better understand contemporary carbon fluxes by bringing together state-of-the art models with remote sensing datasets. Here we report on simulations using NASAs Goddard Earth Observing System Model, version 5 (GEOS-5) which was used to evaluate the consistency of two different sets of observationally constrained land and ocean fluxes with atmospheric CO2 records. Despite the strong data constraint, the average difference in annual terrestrial biosphere flux between the two land (NASA Ames CASA and CASA-GFED) models is 1.7 Pg C for 2009-2010. Ocean models (NOBM and ECCO2-Darwin) differ by 35 in their global estimates of carbon flux with particularly strong disagreement in high latitudes. Based upon combinations of terrestrial and ocean fluxes, GEOS-5 reasonably simulated the seasonal cycle observed at northern hemisphere surface sites and by the Greenhouse gases Observing SATellite (GOSAT) while the model struggled to simulate the seasonal cycle at southern hemisphere surface locations. Though GEOS-5 was able to reasonably reproduce the patterns of XCO2 observed by GOSAT, it struggled to reproduce these aspects of AIRS observations. Despite large differences between land and ocean flux estimates, resulting differences in atmospheric mixing ratio were small, typically less than 5 ppmv at the surface and 3 ppmv in the XCO2 column. A statistical analysis based on the variability of observations shows that flux differences of these magnitudes are difficult to distinguish from natural variability, regardless of measurement platform.

  20. Maguelone (Languedoc coastline, France) : a shallow experimental site for CO2 storage hydrogeophysical monitoring methods.

    NASA Astrophysics Data System (ADS)

    Pezard, Philippe; Denchik, Nataliya; Lofi, Johanna; Perroud, Hervé; Neyens, Denis

    2010-05-01

    conditions encountered in CO2 underground storage, and pressure conditions down to 1500 m depth. The SIMEx ("Shallow Integrated Monitoring Experiment") monitoring experiment is consequently to be deployed at Maguelone by mid 2010. It is a unique opportunity to test in an integrated manner a full suite of coordinated monitoring techniques, either from surface or downhole. While gas injection will be restricted to the reservoir located from about 14 to 17 m, all new holes will be drilled down to 25 m and instrumented over their entire length. The field spread includes, along with the existing holes (MAG4 resistivity observatory and MAG1), a new injection hole perforated only over the 3 meter long interval corresponding to the conglomeratic reservoir, additional downhole electrical observatories (DEO's) placed at variable distance from the injection point, a downhole hydrodynamic observatory (DHO) based on a pore fluid sampling completion from WestBay (SWS), a downhole seismic observatory (DSO) in order to complete the electrical strategy and study how the two methods might be combined for a more efficient description of the saturation/desaturation process associated with the injection (to be installed in MAG1), surface electrical observatory (SEO) and seismic observatory (SSO) with permanent flutes during the injection period, in order to study how surface and downhole monitoring strategies shall complete each other, looking at different volumes, with possible surface/downhole tomographic approaches.

  1. Ground deformation monitoring using RADARSAT-2 DInSAR-MSBAS at the Aquistore CO2 storage site in Saskatchewan (Canada)

    NASA Astrophysics Data System (ADS)

    Czarnogorska, M.; Samsonov, S.; White, D.

    2014-11-01

    The research objectives of the Aquistore CO2 storage project are to design, adapt, and test non-seismic monitoring methods for measurement, and verification of CO2 storage, and to integrate data to determine subsurface fluid distributions, pressure changes and associated surface deformation. Aquistore site is located near Estevan in Southern Saskatchewan on the South flank of the Souris River and west of the Boundary Dam Power Station and the historical part of Estevan coal mine in southeastern Saskatchewan, Canada. Several monitoring techniques were employed in the study area including advanced satellite Differential Interferometric Synthetic Aperture Radar (DInSAR) technique, GPS, tiltmeters and piezometers. The targeted CO2 injection zones are within the Winnipeg and Deadwood formations located at > 3000 m depth. An array of monitoring techniques was employed in the study area including advanced satellite Differential Interferometric Synthetic Aperture Radar (DInSAR) with established corner reflectors, GPS, tiltmeters and piezometers stations. We used airborne LIDAR data for topographic phase estimation, and DInSAR product geocoding. Ground deformation maps have been calculated using Multidimensional Small Baseline Subset (MSBAS) methodology from 134 RADARSAT-2 images, from five different beams, acquired during 20120612-20140706. We computed and interpreted nine time series for selected places. MSBAS results indicate slow ground deformation up to 1 cm/year not related to CO2 injection but caused by various natural and anthropogenic causes.

  2. Surface-downhole and crosshole geoelectrics for monitoring of brine injection at the Ketzin CO2 storage site

    NASA Astrophysics Data System (ADS)

    Rippe, Dennis; Bergmann, Peter; Labitzke, Tim; Wagner, Florian; Schmidt-Hattenberger, Cornelia

    2016-04-01

    The Ketzin pilot site in Germany is the longest operating on-shore CO2 storage site in Europe. From June 2008 till August 2013, a total of ˜67,000 tonnes of CO2 were safely stored in a saline aquifer at depths of 630 m to 650 m. The storage site has now entered the abandonment phase, and continuation of the multi-disciplinary monitoring as part of the national project "CO2 post-injection monitoring and post-closure phase at the Ketzin pilot site" (COMPLETE) provides the unique chance to participate in the conclusion of the complete life cycle of a CO2 storage site. As part of the continuous evaluation of the functionality and integrity of the CO2 storage in Ketzin, from October 12, 2015 till January 6, 2015 a total of ˜2,900 tonnes of brine were successfully injected into the CO2 reservoir, hereby simulating in time-lapse the natural backflow of brine and the associated displacement of CO2. The main objectives of this brine injection experiment include investigation of how much of the CO2 in the pore space can be displaced by brine and if this displacement of CO2 during the brine injection differs from the displacement of formation fluid during the initial CO2 injection. Geophysical monitoring of the brine injection included continuous geoelectric measurements accompanied by monitoring of pressure and temperature conditions in the injection well and two adjacent observation wells. During the previous CO2 injection, the geoelectrical monitoring concept at the Ketzin pilot site consisted of permanent crosshole measurements and non-permanent large-scale surveys (Kiessling et al., 2010). Time-lapse geoelectrical tomographies derived from the weekly crosshole data at near-wellbore scale complemented by six surface-downhole surveys at a scale of 1.5 km showed a noticeable resistivity signature within the target storage zone, which was attributed to the CO2 plume (Schmidt-Hattenberger et al., 2011) and interpreted in terms of relative CO2 and brine saturations (Bergmann

  3. High-rate solar photocatalytic conversion of CO2 and water vapor to hydrocarbon fuels.

    PubMed

    Varghese, Oomman K; Paulose, Maggie; Latempa, Thomas J; Grimes, Craig A

    2009-02-01

    Efficient solar conversion of carbon dioxide and water vapor to methane and other hydrocarbons is achieved using nitrogen-doped titania nanotube arrays, with a wall thickness low enough to facilitate effective carrier transfer to the adsorbing species, surface-loaded with nanodimensional islands of cocatalysts platinum and/or copper. All experiments are conducted in outdoor sunlight at University Park, PA. Intermediate reaction products, hydrogen and carbon monoxide, are also detected with their relative concentrations underlying hydrocarbon production rates and dependent upon the nature of the cocatalysts on the nanotube array surface. Using outdoor global AM 1.5 sunlight, 100 mW/cm(2), a hydrocarbon production rate of 111 ppm cm(-2) h(-1), or approximately 160 microL/(g h), is obtained when the nanotube array samples are loaded with both Cu and Pt nanoparticles. This rate of CO(2) to hydrocarbon production obtained under outdoor sunlight is at least 20 times higher than previous published reports, which were conducted under laboratory conditions using UV illumination.

  4. High resolution pCO2 monitoring reveals ventilation of Bunker Cave (NW Germany) and its impact on speleothem growth

    NASA Astrophysics Data System (ADS)

    Riechelmann, Sylvia; Breitenbach, Sebastian F. M.; Schröder-Ritzrau, Andrea; Immenhauser, Adrian

    2017-04-01

    Understanding the environmental processes that influence geochemical proxies archived in speleothems depends critically on detailed cave monitoring. Cave air pCO2 is one of the most important factors controlling speleothem growth. The pCO2 concentration of cave air depends on (i) the productivity of its source(s), (ii) CO2-transport dynamics through the epikarst and (iii) cave ventilation processes. We monitored the pCO2 concentration ca. 100 m from the lower entrance of the Bunker-Emst-Cave system (NW Germany) with a CORA CO2-logger at a two-hourly resolution between April 2012 and February 2014. Near-atmospheric minimum pCO2 concentrations of 408 ppm are observed in winter, while higher values up to 811 ppm are recorded in summer. Higher summer concentrations are due to increased plant and soil microbial activity, resulting in elevated CO2 in the soil, which is transferred to the cave with infiltrating water. Generally, the front passages of Bunker Cave are well ventilated. Besides the seasonal pattern, pCO2 concentrations vary at diurnal scale. Correlations of pCO2 with the temperature difference between surface and cave air are positive during summer and negative in winter, with no clear pattern for spring and autumn months. Thus, Bunker Cave ventilation is driven by temperature and density differences between cave and surface air, with two entrances at different elevations allowing dynamic ventilation. During summer, relatively cooler cave air flows from the upper to the lower entrance, while in winter this pattern is reversed due to ascending warm cave air. The situation is further complicated by preferential south/southwestern winds that point directly on the cave entrances. Thus, cave ventilation is frequently disturbed, especially during periods of higher wind speed. Modern ventilation systematics only developed when the two cave entrances were artificially opened (1863 and 1926). Before that, ventilation was restricted and cave pCO2 concentrations were

  5. Monitoring of Volcanogenic CO2-Induced Tree Kills with AVIRIS Image Data at Mammoth Mountain, California

    NASA Technical Reports Server (NTRS)

    Hausback, Brian P.; Strong, Mel; Farrar, Chris; Pieri, David

    1998-01-01

    Elevated cold CO2 emissions from the flank of Mammoth Mountain volcano on the southwest rim of the Long Valley Caldera, eastern California, have been the cause of over 100 acres of dead trees in that area since 1990. The source of the CO2 gas is thought to be from one or more magmatic intrusion(s) beneath Mammoth Mountain and is probably related to a period of seismic unrest that began in 1989. The gas rises to the surface probably from depths of a few kilometers, along faults and fracture zones. The gas is at ambient temperature and diffuses from the soil rather than discharging from distinct vents. Typically, soil gas concentrations in tree-kill areas range from 10% to over 90% CO2 by volume, as compared to normal background of < 1% in healthy forest. The gas composition is predominantly CO2 mixed with air (sulfur gases are not elevated), and C and He isotopic ratios are consistent with a magmatic origin for the gas. The total CO2 emission has been estimated at 1200 tons/day, comparable to the emissions at Kilauea. Some of the dead trees are as old as 250 years, suggesting that similar anomalous gas discharge has not occurred over the previous few hundred years. The delta C-13/12 ratio in the Mammoth Mountain CO2 emission averages about -4.5 (PDB standard). This is consistent with a mantle source for the carbon. However, the large volume of the emission suggests that not all of the CO2 is necessarily being generated from the 1989 intrusion. The voluminous gas could be leaking from a vapor-rich zone, capped by an impermeable layer, that was supplied CO2 from degassing of many small magma bodies that intruded beneath the mountain over a period of decades or centuries. Earthquakes in 1989 could have fractured the capping layer and provided pathways for the escape Of CO2 to the surface. Alternatively, some of the CO2 could be derived from contact metamorphism of carbonate rocks intruded by magma. Carbonate-bearing Paleozoic roof pendents crop out in close proximity

  6. Monitoring of Volcanogenic CO2-Induced Tree Kills with AVIRIS Image Data at Mammoth Mountain, California

    NASA Technical Reports Server (NTRS)

    Hausback, Brian P.; Strong, Mel; Farrar, Chris; Pieri, David

    1998-01-01

    Elevated cold CO2 emissions from the flank of Mammoth Mountain volcano on the southwest rim of the Long Valley Caldera, eastern California, have been the cause of over 100 acres of dead trees in that area since 1990. The source of the CO2 gas is thought to be from one or more magmatic intrusion(s) beneath Mammoth Mountain and is probably related to a period of seismic unrest that began in 1989. The gas rises to the surface probably from depths of a few kilometers, along faults and fracture zones. The gas is at ambient temperature and diffuses from the soil rather than discharging from distinct vents. Typically, soil gas concentrations in tree-kill areas range from 10% to over 90% CO2 by volume, as compared to normal background of < 1% in healthy forest. The gas composition is predominantly CO2 mixed with air (sulfur gases are not elevated), and C and He isotopic ratios are consistent with a magmatic origin for the gas. The total CO2 emission has been estimated at 1200 tons/day, comparable to the emissions at Kilauea. Some of the dead trees are as old as 250 years, suggesting that similar anomalous gas discharge has not occurred over the previous few hundred years. The delta C-13/12 ratio in the Mammoth Mountain CO2 emission averages about -4.5 (PDB standard). This is consistent with a mantle source for the carbon. However, the large volume of the emission suggests that not all of the CO2 is necessarily being generated from the 1989 intrusion. The voluminous gas could be leaking from a vapor-rich zone, capped by an impermeable layer, that was supplied CO2 from degassing of many small magma bodies that intruded beneath the mountain over a period of decades or centuries. Earthquakes in 1989 could have fractured the capping layer and provided pa