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Sample records for waterflood co2 miscible

  1. Post Waterflood CO2 Miscible Flood in Light Oil, Fluvial-Dominated Deltaic Reservoir (Pre-Work and Project Proposal - Appendix)

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    Bou-Mikael, Sami

    2002-02-05

    The main objective of the Port Neches Project was to determine the feasibility and producibility of CO2 miscible flooding techniques enhanced with horizontal drilling applied to a Fluvial Dominated Deltaic reservoir. The second was to disseminate the knowledge gained through established Technology Transfer mechanisms to support DOE's programmatic objectives of increasing domestic oil production and reducing abandonment of oil fields.

  2. An Improved CO2-Crude Oil Minimum Miscibility Pressure Correlation

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    Hao Zhang

    2015-01-01

    Full Text Available Minimum miscibility pressure (MMP, which plays an important role in miscible flooding, is a key parameter in determining whether crude oil and gas are completely miscible. On the basis of 210 groups of CO2-crude oil system minimum miscibility pressure data, an improved CO2-crude oil system minimum miscibility pressure correlation was built by modified conjugate gradient method and global optimizing method. The new correlation is a uniform empirical correlation to calculate the MMP for both thin oil and heavy oil and is expressed as a function of reservoir temperature, C7+ molecular weight of crude oil, and mole fractions of volatile components (CH4 and N2 and intermediate components (CO2, H2S, and C2~C6 of crude oil. Compared to the eleven most popular and relatively high-accuracy CO2-oil system MMP correlations in the previous literature by other nine groups of CO2-oil MMP experimental data, which have not been used to develop the new correlation, it is found that the new empirical correlation provides the best reproduction of the nine groups of CO2-oil MMP experimental data with a percentage average absolute relative error (%AARE of 8% and a percentage maximum absolute relative error (%MARE of 21%, respectively.

  3. Improved Efficiency of Miscible CO2 Floods and Enhanced Prospects for CO2 Flooding Heterogeneous Reservoirs

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    Grigg, Reid B.; Schechter, David S.

    1999-10-15

    The goal of this project is to improve the efficiency of miscible CO2 floods and enhance the prospects for flooding heterogeneous reservoirs. This report provides results of the second year of the three-year project that will be exploring three principles: (1) Fluid and matrix interactions (understanding the problems). (2) Conformance control/sweep efficiency (solving the problems. 3) Reservoir simulation for improved oil recovery (predicting results).

  4. Fluid characterization for miscible EOR projects and CO2 sequestration

    DEFF Research Database (Denmark)

    Jessen, Kristian; Stenby, Erling Halfdan

    2007-01-01

    Accurate performance prediction of miscible enhanced-oil-recovery (EOR) projects or CO, sequestration in depleted oil and gas reservoirs relies in part on the ability of an equation-of-state (EOS) model to adequately represent the properties of a wide range of mixtures of the resident fluid...... to condition an EOS model before application in performance evaluation of miscible displacements. However, no clear understanding exists of the impact on the resultant accuracy of the selected characterization procedure when the fluid description is subsequently included in reservoir simulation. In this paper...... in the data reduction and demonstrate that for some gas/oil systems, swelling tests do not contribute to a more accurate prediction of multicontact miscibility. Finally, we report on the impact that use of EOS models based on different characterization procedures can have on recovery predictions from dynamic...

  5. Determining CO2 storage potential during miscible CO2 enhanced oil recovery: Noble gas and stable isotope tracers

    Science.gov (United States)

    Shelton, Jenna L.; McIntosh, Jennifer C.; Hunt, Andrew; Beebe, Thomas L; Parker, Andrew D; Warwick, Peter D.; Drake, Ronald; McCray, John E.

    2016-01-01

    Rising atmospheric carbon dioxide (CO2) concentrations are fueling anthropogenic climate change. Geologic sequestration of anthropogenic CO2 in depleted oil reservoirs is one option for reducing CO2 emissions to the atmosphere while enhancing oil recovery. In order to evaluate the feasibility of using enhanced oil recovery (EOR) sites in the United States for permanent CO2 storage, an active multi-stage miscible CO2flooding project in the Permian Basin (North Ward Estes Field, near Wickett, Texas) was investigated. In addition, two major natural CO2 reservoirs in the southeastern Paradox Basin (McElmo Dome and Doe Canyon) were also investigated as they provide CO2 for EOR operations in the Permian Basin. Produced gas and water were collected from three different CO2 flooding phases (with different start dates) within the North Ward Estes Field to evaluate possible CO2 storage mechanisms and amounts of total CO2retention. McElmo Dome and Doe Canyon were sampled for produced gas to determine the noble gas and stable isotope signature of the original injected EOR gas and to confirm the source of this naturally-occurring CO2. As expected, the natural CO2produced from McElmo Dome and Doe Canyon is a mix of mantle and crustal sources. When comparing CO2 injection and production rates for the CO2 floods in the North Ward Estes Field, it appears that CO2 retention in the reservoir decreased over the course of the three injections, retaining 39%, 49% and 61% of the injected CO2 for the 2008, 2010, and 2013 projects, respectively, characteristic of maturing CO2 miscible flood projects. Noble gas isotopic composition of the injected and produced gas for the flood projects suggest no active fractionation, while δ13CCO2 values suggest no active CO2dissolution into formation water, or mineralization. CO2 volumes capable of dissolving in residual formation fluids were also estimated along with the potential to store pure-phase supercritical CO2. Using a combination

  6. Evaluation of miscible and immiscible CO2 injection in one of the Iranian oil fields

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    Aref Hashemi Fath

    2014-09-01

    Full Text Available Carbon dioxide (CO2 flooding is one of the most important methods for enhanced oil recovery (EOR because it not only increases oil recovery efficiency but also causes a reduction of greenhouse gas emissions. It is a very complex system, involving phase behavior that could increase the recovery of oil by means of swelling, evaporation and decreasing viscosity of the oil. In this study, a reservoir modeling approach was used to evaluate immiscible and miscible CO2 flooding in a fractured oil field. To reduce simulation time, we grouped fluid components into 10 pseudo-components. The 3-parameter, Peng–Robinson Equation of State (EOS was used to match PVT experimental data by using the PVTi software. A one-dimensional slim-tube model was defined using ECLIPSE 300 software to determine the minimum miscibility pressure (MMP for injection of CO2. We used FloGrid software for making a reservoir static model and the reservoir model was calibrated using manual and assisted history matching methods. Then various scenarios of natural depletion, immiscible and miscible CO2 injection have been simulated by ECLIPSE 300 software and then the simulation results of scenarios have been compared. Investigation of simulation results shows that the oil recovery factor in miscible CO2 injection scenario is more than other methods.

  7. Evaluation of miscible and immiscible CO2 injection in one of the Iranian oil fields

    OpenAIRE

    Hashemi Fath, Aref; Pouranfard, Abdol-Rasoul

    2014-01-01

    Carbon dioxide (CO2) flooding is one of the most important methods for enhanced oil recovery (EOR) because it not only increases oil recovery efficiency but also causes a reduction of greenhouse gas emissions. It is a very complex system, involving phase behavior that could increase the recovery of oil by means of swelling, evaporation and decreasing viscosity of the oil. In this study, a reservoir modeling approach was used to evaluate immiscible and miscible CO2 flooding in a fractured oil ...

  8. Design and Implementation of a CO2 Flood Utilizing Advanced Reservoir Characterization and Horizontal Injection Wells In a Shallow Shelf Carbonate Approaching Waterflood Depletion, Class II

    Energy Technology Data Exchange (ETDEWEB)

    Wier, Don R. Chimanhusky, John S.; Czirr, Kirk L.; Hallenbeck, Larry; Gerard, Matthew G.; Dollens, Kim B.; Owen, Rex; Gaddis, Maurice; Moshell, M.K.

    2002-11-18

    The purpose of this project was to economically design an optimum carbon dioxide (CO2) flood for a mature waterflood nearing its economic abandonment. The original project utilized advanced reservoir characterization and CO2 horizontal injection wells as the primary methods to redevelop the South Cowden Unit (SCU). The development plans; project implementation and reservoir management techniques were to be transferred to the public domain to assist in preventing premature abandonment of similar fields.

  9. Optimal Control of Partially Miscible Two-Phase Flow with Applications to Subsurface CO2 Sequestration

    KAUST Repository

    Simon, Moritz

    2013-01-01

    Motivated by applications in subsurface CO2 sequestration, we investigate constrained optimal control problems with partially miscible two-phase flow in porous media. The objective is, e.g., to maximize the amount of trapped CO2 in an underground reservoir after a fixed period of CO2 injection, where the time-dependent injection rates in multiple wells are used as control parameters. We describe the governing two-phase two-component Darcy flow PDE system and formulate the optimal control problem. For the discretization we use a variant of the BOX method, a locally conservative control-volume FE method. The timestep-wise Lagrangian of the control problem is implemented as a functional in the PDE toolbox Sundance, which is part of the HPC software Trilinos. The resulting MPI parallelized Sundance state and adjoint solvers are linked to the interior point optimization package IPOPT. Finally, we present some numerical results in a heterogeneous model reservoir.

  10. Experimental Study and Performance Investigation of Miscible Water-Alternating-CO2 Flooding for Enhancing Oil Recovery in the Sarvak Formation

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    Rahimi Vahid

    2017-11-01

    Full Text Available This experimental study is aimed at evaluating the performance of the miscible Water-Alternating-CO2 (CO2-WAG flooding as a function of slug size and WAG ratio based on the ultimate oil recovery in the Sarvak formation. In this research, initially the slim-tube apparatus was used to determine the Minimum Miscibility Pressure (MMP of the Sarvak heavy oil and CO2 at the constant reservoir temperature. Then, a total of seven core flooding experiments were performed by using the sandstone core samples collected from the Sarvak formation. These experiments were conducted through respective water flooding, miscible continuous CO2 flooding, and miscible CO2-WAG flooding. In the miscible CO2-WAG flooding, different WAG slug sizes of 0.15, 0.25, and 0.50 Pore Volume (PV and different WAG ratios of 1:1, 2:1, and 1:2 were applied to investigate their effects on the oil Recovery Factor (RF in the Sarvak formation. The results showed that, in general, the miscible CO2 Enhanced Oil Recovery (CO2-EOR process is capable of mobilizing the heavy oil and achieving a high and significant oil RF in the Sarvak formation. The miscible CO2-WAG flooding has the highest oil RF (84.3% in comparison with water flooding (37.7%, and miscible continuous CO2 flooding (61.5%. In addition, using a smaller WAG slug size for miscible CO2-WAG flooding leads to a higher oil RF. The optimum WAG ratio of the miscible CO2-WAG flooding for the Sarvak formation is approximately 2:1. The results also demonstrated that, more than 50% of the heavy oil is produced in the first two cycles of the miscible CO2-WAG flooding. The optimum miscible CO2-WAG flooding has a much less CO2 consumption than the miscible continuous CO2 flooding.

  11. Predicting CO2 Minimum Miscibility Pressure (MMP Using Alternating Conditional Expectation (ACE Algorithm

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    Alomair O.

    2015-11-01

    Full Text Available Miscible gas injection is one of the most important enhanced oil recovery (EOR approaches for increasing oil recovery. Due to the massive cost associated with this approach a high degree of accuracy is required for predicting the outcome of the process. Such accuracy includes, the preliminary screening parameters for gas miscible displacement; the “Minimum Miscibility Pressure” (MMP and the availability of the gas. All conventional and stat-of-art MMP measurement methods are either time consuming or decidedly cost demanding processes. Therefore, in order to address the immediate industry demands a nonparametric approach, Alternating Conditional Expectation (ACE, is used in this study to estimate MMP. This algorithm Breiman and Friedman [Brieman L., Friedman J.H. (1985 J. Am. Stat. Assoc. 80, 391, 580-619]estimates the transformations of a set of predictors (here C1, C2, C3, C4, C5, C6, C7+, CO2, H2S, N2, Mw5+, Mw7+ and T and a response (here MMP that produce the maximum linear effect between these transformed variables. One hundred thirteen MMP data points are considered both from the relevant published literature and the experimental work. Five MMP measurements for Kuwaiti Oil are included as part of the testing data. The proposed model is validated using detailed statistical analysis; a reasonably good value of correlation coefficient 0.956 is obtained as compare to the existing correlations. Similarly, standard deviation and average absolute error values are at the lowest as 139 psia (8.55 bar and 4.68% respectively. Hence, it reveals that the results are more reliable than the existing correlations for pure CO2 injection to enhance oil recovery. In addition to its accuracy, the ACE approach is more powerful, quick and can handle a huge data.

  12. Magnetic resonance imaging on CO(2) miscible and immiscible displacement in oil-saturated glass beads pack.

    Science.gov (United States)

    Liu, Yu; Zhao, Yuechao; Zhao, Jiafei; Song, Yongchen

    2011-10-01

    In this study, the displacement processes were observed as gaseous or supercritical CO(2) was injected into n-decane-saturated glass beads packs using a 400-MHz magnetic resonance imaging (MRI) system. Two-dimensional images of oil distribution in the vertical median section were obtained using a spin-echo pulse sequence. Gas channeling and viscous fingering appeared obviously in immiscible gaseous CO(2) displacement. A piston-like displacement front was detected in miscible supercritical CO(2) displacement that provided high sweep efficiency. MRI images were processed with image intensity analysis methods to obtain the saturation profiles. Final oil residual saturations and displacement coefficients were also estimated using this imaging intensity analysis. It was proved that miscible displacement can enhance the efficiency of CO(2) displacement notably. Finally, a special coreflood analysis method was applied to estimate the effects of capillary, viscosity and buoyancy based on the obtained saturation data. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Simulation Study on Miscibility Effect of CO2/Solvent Injection for Enhanced Oil Recovery at Nonisothermal Conditions

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    Moon Sik Jeong

    2016-01-01

    Full Text Available The minimum miscibility pressure (MMP determines the main mechanism of CO2 flooding, which is either an immiscible or miscible process. This paper examines the recovery improvements of CO2 flooding in terms of both the injection temperature and solvent composition. The results show that a lower temperature injection and LPG (liquefied petroleum gas mixture can considerably improve oil recovery due to the reduced MMP in the swept area caused by the injected solvent. For the pure CO2 injection at the reservoir temperature, oil recovery is 59% after 1.0 PV CO2 injection. The oil recoveries by CO2-LPG mixtures are improved to 73% with 0.1 mole fractions of LPG and 81% with 0.2 mole fractions of LPG. The recovery factor from low-temperature CO2 injection is 78%, which is 32% higher compared to the isothermal case. The recoveries obtained by low-temperature CO2-LPG injection increase up to 87% of the initial oil. Heat transfer between the reservoir and the formation of over/underburden should be considered in order to describe the process more accurately. Additionally, the recovery factors from the heat transfer models are decreased by 4–12% in comparison with the original nonisothermal models.

  14. Displacement front behavior of near miscible CO2flooding in decane saturated synthetic sandstone cores revealed by magnetic resonance imaging.

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    Liu, Yu; Teng, Ying; Jiang, Lanlan; Zhao, Jiafei; Zhang, Yi; Wang, Dayong; Song, Yongchen

    2017-04-01

    It is of great importance to study the CO 2 -oil two-phase flow characteristic and displacement front behavior in porous media, for understanding the mechanisms of CO 2 enhanced oil recovery. In this work, we carried out near miscible CO 2 flooding experiments in decane saturated synthetic sandstone cores to investigate the displacement front characteristic by using magnetic resonance imaging technique. Experiments were done in three consolidated sandstone cores with the permeabilities ranging from 80 to 450mD. The oil saturation maps and the overall oil saturation during CO 2 injections were obtained from the intensity of magnetic resonance imaging. Finally the parameters of the piston-like displacement fronts, including the front velocity and the front geometry factor (the length to width ratio) were analyzed. Experimental results showed that the near miscible vertical upward displacement is instable above the minimum miscible pressure in the synthetic sandstone cores. However, low permeability can restrain the instability to some extent. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Enhanced Oil Recovery (EOR by Miscible CO2 and Water Flooding of Asphaltenic and Non-Asphaltenic Oils

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    Edwin A. Chukwudeme

    2009-09-01

    Full Text Available An EOR study has been performed applying miscible CO2 flooding and compared with that for water flooding. Three different oils are used, reference oil (n-decane, model oil (n-C10, SA, toluene and 0.35 wt % asphaltene and crude oil (10 wt % asphaltene obtained from the Middle East. Stearic acid (SA is added representing a natural surfactant in oil. For the non-asphaltenic oil, miscible CO2 flooding is shown to be more favourable than that by water. However, it is interesting to see that for first years after the start of the injection (< 3 years it is shown that there is almost no difference between the recovered oils by water and CO2, after which (> 3 years oil recovery by gas injection showed a significant increase. This may be due to the enhanced performance at the increased reservoir pressure during the first period. Maximum oil recovery is shown by miscible CO2 flooding of asphaltenic oil at combined temperatures and pressures of 50 °C/90 bar and 70 °C/120 bar (no significant difference between the two cases, about 1% compared to 80 °C/140 bar. This may support the positive influence of the high combined temperatures and pressures for the miscible CO2 flooding; however beyond a certain limit the oil recovery declined due to increased asphaltene deposition. Another interesting finding in this work is that for single phase oil, an almost linear relationship is observed between the pressure drop and the asphaltene deposition regardless of the flowing fluid pressure.

  16. Estimation of minimum miscibility pressure (MMP) of CO2 and liquid n-alkane systems using an improved MRI technique.

    Science.gov (United States)

    Liu, Yu; Jiang, Lanlan; Song, Yongchen; Zhao, Yuechao; Zhang, Yi; Wang, Dayong

    2016-02-01

    Minimum miscible pressure (MMP) of gas and oil system is a key parameter for the injection system design of CO2 miscible flooding. Some industrial standard approaches such as the experiment using a rising bubble apparatus (RBA), the slim tube tests (STT), the pressure-density diagram (PDD), etc. have been applied for decades to determine the MMP of gas and oil. Some theoretical or experiential calculations of the MMP were also applied to the gas-oil miscible system. In the present work, an improved technique based on our previous research for the estimation of the MMP by using magnetic resonance imaging (MRI) was proposed. This technique was then applied to the CO2 and n-alkane binary and ternary systems to observe the mixing procedure and to study the miscibility. MRI signal intensities, which represent the proton concentration of n-alkane in both the hydrocarbon rich phase and the CO2 rich phase, were plotted as a reference for determining the MMP. The accuracy of the MMP obtained by using this improved technique was enhanced comparing with the data obtained from our previous works. The results also show good agreement with other established techniques (such as the STT) in previous published works. It demonstrates increases of MMPs as the temperature rise from 20 °C to 37.8 °C. The MMPs of CO2 and n-alkane systems are also found to be proportional to the carbon number in the range of C10 to C14. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. DESIGN AND IMPLEMENTATION OF A CO2 FLOOD UTILIZING ADVANCED RESERVOIR CHARACTERIZATION AND HORIZONTAL INJECTION WELLS IN A SHALLOW SHELF CARBONATE APPROACHING WATERFLOOD DEPLETION

    Energy Technology Data Exchange (ETDEWEB)

    K.J. Harpole; Ed G. Durrett; Susan Snow; J.S. Bles; Carlon Robertson; C.D. Caldwell; D.J. Harms; R.L. King; B.A. Baldwin; D. Wegener; M. Navarrette

    2002-09-01

    The purpose of this project was to economically design an optimum carbon dioxide (CO{sub 2}) flood for a mature waterflood nearing its economic abandonment. The original project utilized advanced reservoir characterization and CO{sub 2} horizontal injection wells as the primary methods to redevelop the South Cowden Unit (SCU). The development plans; project implementation and reservoir management techniques were to be transferred to the public domain to assist in preventing premature abandonment of similar fields. The Unit was a mature waterflood with water cut exceeding 95%. Oil must be mobilized through the use of a miscible or near-miscible fluid to recover significant additional reserves. Also, because the unit was relatively small, it did not have the benefit of economies of scale inherent in normal larger scale projects. Thus, new and innovative methods were required to reduce investment and operating costs. Two primary methods used to accomplish improved economics were use of reservoir characterization to restrict the flood to the higher quality rock in the unit and use of horizontal injection wells to cut investment and operating costs. The project consisted of two budget phases. Budget Phase I started in June 1994 and ended late June 1996. In this phase Reservoir Analysis, Characterization Tasks and Advanced Technology Definition Tasks were completed. Completion enabled the project to be designed, evaluated, and an Authority for Expenditure (AFE) for project implementation submitted to working interest owners for approval. Budget Phase II consisted of the implementation and execution of the project in the field. Phase II was completed in July 2001. Performance monitoring, during Phase II, by mid 1998 identified the majority of producing wells which under performed their anticipated withdrawal rates. Newly drilled and re-activated wells had lower offtake rates than originally forecasted. As a result of poor offtake, higher reservoir pressure was a concern

  18. A Practical Approach for Formation Damage Control in Both Miscible and Immiscible CO2 Gas Flooding in Asphaltenic Crude Systems Using Water Slugs and Injection Parameters

    Science.gov (United States)

    David, Sergio Z.

    CO2 flooding has proven to be an effective technique for enhanced oil recovery. However, the application of CO2 flooding in the recovery process of asphaltenic crude systems is often avoided, as high asphaltene precipitation rates may occur. While the effects of asphaltene concetration and CO2 injection pressure on asphaltene precipitation rate have been the focus of many studies, asphaltene precipitation rate is not a reliable factor to predict the magnitude of asphaltene-induced formation damage. Wettability alteration is only caused by the immobile asphaltene deposits on the rock surface. The enternmaint of flocs may occur at high fluid velocity. Morover, the effective permeability reduction is only caused by the flocs, which have become large enough to block the pore throats. The dissociation of the flocs may occur under certain flow conditions. In this study, a compositional reservoir simulation was conducted using Eclipse 300 to investigate the injection practice, which avoids asphaltene-induced formation damage during both immiscible and miscible CO2 flooding in asphaltenic crude system. Without injection, at pressure above bubble point, slight precipitation occurred in the zone of the lowest pressure near the producing well. As pressure approached the bubble point, precipitation increased due to the change in the hydrocarbon composition, which suggested that the potential of asphaltene-induced formation damage is determined by the overall fluid composition. At very low pressure, precipitation decreased due to the increase in the density. As CO2 was injected below the minimum miscibility pressure, a slight precipitation occurred in the transition zone at the gas-oil interface due to the microscopic diffusion of the volatile hydrocarbon components caused by the local concentration gradients. The increase in CO2 injection rate did not significantly increase the precipitation rate. As CO2 was injected at pressure above the minimum miscibility pressure

  19. Waterflood surveillance

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    Ghauri, W.K.

    1976-01-01

    Surveillance, in order for it to be effective, should be implemented through an organization with adequate staffing and technology. Engineering and field operations organizations should be complementary, providing for specific lines of communications, and yet at the same time encouraging informal personal exchanges between both groups. Surveillance of a waterflood project requires constant cooperation between the 2 groups in order to collect, document, and analyze an immense quantity of data, and to conduct an efficient operation. As is customary in many oil-field operations, project well reviews are held periodically to determine if the wells are performing satisfactorily. The periodic well review is an integral part of flood surveillance and is a highly practical method of (1) keeping ahead of a waterflood project, instead of continually putting out brush fires, and (2) bringing together the expertise of the engineering, field operations, and well analysis groups in an action-oriented session. Surveillance techniques and procedures are described, but the author states that there is no cookbook technique for flood surveillance. It is laborious, detailed work, and oftentimes, with little glamour. Its rewards are evident in successful project performance, prevention of loss of anticipated reserves, and addition of reserves not forseen previously.

  20. Post waterflood CO2 miscible flood in light oil fluvial - dominated deltaic reservoirs. Technical progress report, October 1, 1994--December 30, 1994. 1st Quarter, fiscal year 1995

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    NONE

    1994-01-15

    Production is averaging about 450 BOPD for the quarter. The fluctuation was primarily due to a temporary shutdown of CO{sub 2} delivery and maturing of the first WAG cycle. CO{sub 2} and water injection were reversed again in order to optimize changing yields and water cuts in the producing wells. Measured BHP was close to the anticipated value. A limited CO{sub 2} volume of 120 MMCF was injected to stimulate well Kuhn No. 6 to test the Huff-Puff process, since the well did not respond to CO{sub 2} injection from the main reservoir. The well will be placed on February 1, 1995. Total CO{sub 2} injection averaged this quarter about 8.8 MMCFD, including 3.6 MMCFD purchased CO{sub 2} from Cardox. The stratigraphy of the sand deposits is also discussed.

  1. Improved efficiency of miscible CO2 floods and enhanced prospects for CO2 flooding heterogeneous reservoirs. Final report, April 17, 1991--May 31, 1997

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    Grigg, R.B.; Schechter, D.S.

    1998-02-01

    From 1986 to 1996, oil recovery in the US by gas injection increased almost threefold, to 300,000 bbl/day. Carbon dioxide (CO{sub 2}) injection projects make up three-quarters of the 191,139 bbl/day production increase. This document reports experimental and modeling research in three areas that is increasing the number of reservoirs in which CO{sub 2} can profitably enhance oil recovery: (1) foams for selective mobility reduction (SMR) in heterogeneous reservoirs, (2) reduction of the amount of CO{sub 2} required in CO{sub 2} floods, and (3) low interfacial tension (97) processes and the possibility of CO{sub 2} flooding in naturally fractured reservoirs. CO{sub 2} injection under miscible conditions can effectively displace oil, but due to differences in density and viscosity the mobility of CO{sub 2} is higher than either oil or water. High CO{sub 2} mobility causes injection gas to finger through a reservoir, causing such problems as early gas breakthrough, high gas production rates, excessive injection gas recycling, and bypassing of much of the reservoir oil. These adverse effects are exacerbated by increased reservoir heterogeneity, reaching an extreme in naturally fractured reservoirs. Thus, many highly heterogeneous reservoirs have not been considered for CO{sub 2} injection or have had disappointing recoveries. One example is the heterogeneous Spraberry trend in west Texas, where only 10% of its ten billion barrels of original oil in place (OOIP) are recoverable by conventional methods. CO{sub 2} mobility can be reduced by injecting water (brine) alternated with CO{sub 2} (WAG) and then further reduced by adding foaming agents-surfactants. In Task 1, we studied a unique foam property, selective mobility reduction (SMR), that effectively reduces the effects of reservoir heterogeneity. Selective mobility reduction creates a more uniform displacement by decreasing CO{sub 2} mobility in higher permeability zones more than in lower permeability zones.

  2. CO2 Huff-n-Puff Process in a Light Oil Shallow Shelf Carbonate Reservoir

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    Boomer, R.J.; Cole, R.; Kovar, M.; Prieditis, J.; Vogt, J.; Wehner, S.

    1999-02-24

    The application cyclic CO2, often referred to as the CO2 Huff-n-Puff process, may find its niche in the maturing waterfloods of the Permian Basin. Coupling the CO2 Huff-n-Puff process to miscible flooding applications could provide the needed revenue to sufficiently mitigate near-term negative cash flow concerns in capital-intensive miscible projects. Texaco Exploration and Production Inc. and the US Department of Energy have teamed up in a attempt to develop the CO2 Huff-n-Puff process in the Grayburg and San Andres formations which are light oil, shallow shelf carbonate reservoirs that exist throughout the Permian Basin. This cost-shared effort is intended to demonstrate the viability of this underutilized technology in a specific class of domestic reservoir.

  3. Adjoint based optimal control of partially miscible two-phase flow in porous media with applications to CO2 sequestration in underground reservoirs

    KAUST Repository

    Simon, Moritz

    2014-11-14

    © 2014, Springer Science+Business Media New York. With the target of optimizing CO2 sequestration in underground reservoirs, we investigate constrained optimal control problems with partially miscible two-phase flow in porous media. Our objective is to maximize the amount of trapped CO2 in an underground reservoir after a fixed period of CO2 injection, while time-dependent injection rates in multiple wells are used as control parameters. We describe the governing two-phase two-component Darcy flow PDE system, formulate the optimal control problem and derive the continuous adjoint equations. For the discretization we apply a variant of the so-called BOX method, a locally conservative control-volume FE method that we further stabilize by a periodic averaging feature to reduce oscillations. The timestep-wise Lagrange function of the control problem is implemented as a variational form in Sundance, a toolbox for rapid development of parallel FE simulations, which is part of the HPC software Trilinos. We discuss the BOX method and our implementation in Sundance. The MPI parallelized Sundance state and adjoint solvers are linked to the interior point optimization package IPOPT, using limited-memory BFGS updates for approximating second derivatives. Finally, we present and discuss different types of optimal control results.

  4. 4-D High-Resolution Seismic Reflection Monitoring of Miscible CO2 Injected into a Carbonate Reservoir

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    Richard D. Miller; Abdelmoneam E. Raef; Alan P. Byrnes; William E. Harrison

    2007-06-30

    The objective of this research project was to acquire, process, and interpret multiple high-resolution 3-D compressional wave and 2-D, 2-C shear wave seismic data in the hopes of observing changes in fluid characteristics in an oil field before, during, and after the miscible carbon dioxide (CO{sub 2}) flood that began around December 1, 2003, as part of the DOE-sponsored Class Revisit Project (DOE No.DE-AC26-00BC15124). Unique and key to this imaging activity is the high-resolution nature of the seismic data, minimal deployment design, and the temporal sampling throughout the flood. The 900-m-deep test reservoir is located in central Kansas oomoldic limestones of the Lansing-Kansas City Group, deposited on a shallow marine shelf in Pennsylvanian time. After 30 months of seismic monitoring, one baseline and eight monitor surveys clearly detected changes that appear consistent with movement of CO{sub 2} as modeled with fluid simulators and observed in production data. Attribute analysis was a very useful tool in enhancing changes in seismic character present, but difficult to interpret on time amplitude slices. Lessons learned from and tools/techniques developed during this project will allow high-resolution seismic imaging to be routinely applied to many CO{sub 2} injection programs in a large percentage of shallow carbonate oil fields in the midcontinent.

  5. Using CO2 Prophet to estimate recovery factors for carbon dioxide enhanced oil recovery

    Science.gov (United States)

    Attanasi, Emil D.

    2017-07-17

    IntroductionThe Oil and Gas Journal’s enhanced oil recovery (EOR) survey for 2014 (Koottungal, 2014) showed that gas injection is the most frequently applied method of EOR in the United States and that carbon dioxide (CO2 ) is the most commonly used injection fluid for miscible operations. The CO2-EOR process typically follows primary and secondary (waterflood) phases of oil reservoir development. The common objective of implementing a CO2-EOR program is to produce oil that remains after the economic limit of waterflood recovery is reached. Under conditions of miscibility or multicontact miscibility, the injected CO2 partitions between the gas and liquid CO2 phases, swells the oil, and reduces the viscosity of the residual oil so that the lighter fractions of the oil vaporize and mix with the CO2 gas phase (Teletzke and others, 2005). Miscibility occurs when the reservoir pressure is at least at the minimum miscibility pressure (MMP). The MMP depends, in turn, on oil composition, impurities of the CO2 injection stream, and reservoir temperature. At pressures below the MMP, component partitioning, oil swelling, and viscosity reduction occur, but the efficiency is increasingly reduced as the pressure falls farther below the MMP. CO2-EOR processes are applied at the reservoir level, where a reservoir is defined as an underground formation containing an individual and separate pool of producible hydrocarbons that is confined by impermeable rock or water barriers and is characterized by a single natural pressure system. A field may consist of a single reservoir or multiple reservoirs that are not in communication but which may be associated with or related to a single structural or stratigraphic feature (U.S. Energy Information Administration [EIA], 2000). The purpose of modeling the CO2-EOR process is discussed along with the potential CO2-EOR predictive models. The data demands of models and the scope of the assessments require tradeoffs between reservoir

  6. Field-scale investigation of different miscible CO2-injection modes to improve oil recovery in a clastic highly heterogeneous reservoir

    National Research Council Canada - National Science Library

    Jaber, Ahmed Khalil; Awang, Mariyamni B

    Carbon dioxide flooding is considered one of the most commonly used miscible gas injections to improve oil recovery, and its applicability has grown significantly due to its availability, greenhouse...

  7. Waterflood planning pointers

    Energy Technology Data Exchange (ETDEWEB)

    Godsey, J.E.

    1972-10-01

    Despite extensive research into and widespread experience with waterflooding, there are still many different ideas regarding its various aspects, such as oil saturation, injection patterns, and equipment selection. Periodic review of past successful and unsuccessful waterfloods will yield positive answers to the many remaining questions. Performing feasibility studies, participating in unitization proceedings (from engineering feasibility studies, through operators committee meetings, through state regulatory agencies), designing and installing flood equipment, and operating floods to their depletion, have provided some empirical conclusions about some of these controversial questions and/or practices. Oil in place in a reservoir must be determined within reason to aid in primary field development. This determination increases in importance when making decisions about secondary recovery efforts, and increases again exponentially when tertiary recovery methods are considered. Geometric injection patterns generally result in higher recovery and profits. However, strict uniform patterns are seldom attained for a variety of reasons. In many instances, pumping unit sizing is passed over lightly. In all too many cases, pumping equipment is selected by assuming maximum production will occur in all wells at the same time, and/or that maximum production will be identical in all wells.

  8. Polymers reduce risk in waterflooding

    Energy Technology Data Exchange (ETDEWEB)

    McCartney, J.A.; Sloat, B.

    1972-12-01

    Results of a waterflood and a polymer flood in the same formation are compared with computer model runs to show that the model is a reliable and efficient screening tool easily applied to any formation considered a waterflood prospect. Wyoming Minnelusa, Oklahoma Sims, and California Chapman formations are used to compare the present worth value of waterfloods and polymer floods. In addition to recovering more oil in a shorter time, polymer floods handle much less produced water. In 3 of the 4 examples, reduced water handling costs were more than enough to balance the front end cost of the polymer treatment program. Properly assessing the time value of money invested in and generated by polymer oil recovery projects is a job well suited for a computer model. The results are compared with predictions.

  9. Smart Waterflooding in Carbonate Reservoirs

    DEFF Research Database (Denmark)

    Zahid, Adeel

    in porous media. The main conclusion of most previous studies was that it is the rock wettability alteration towards more water wetting condition that helps improving the oil recovery. In the first step of this project, we focused on verifying this conclusion. Coreflooding experiments were carried out using...... imbibition rather than forced flooding. The objective of the third step of this project was to investigate the potential of high salinity waterflooding process by carrying out experiments with reservoir chalk samples. We carried out waterflooding instead of spontaneous imbibition using core plugs...... reservoirs by injecting brine of low salinity. However, this effect has not been thoroughly investigated for carbonates. At the final stage of this project, we have experimentally investigated the oil recovery potential of low salinity water flooding in the carbonate rocks. We used both reservoir carbonate...

  10. Compositional and Relative Permeability Hysteresis Effects on Near-Miscible WAG

    DEFF Research Database (Denmark)

    Christensen, Jes Reimer; Stenby, Erling Halfdan; Skauge, Arne

    1998-01-01

    , and a compositional model was used to compare different production strategies e.g. waterflooding and a near-miscible (WAG) injection. In the WAG scheme both dry and wet (rich) hydrocarbon gases have been considered for injection. The phase behaviour was quantified by comparing the performance of the different...

  11. Recovery of waterflood residual oil

    Energy Technology Data Exchange (ETDEWEB)

    Orkiszewski, J.

    1966-03-15

    This is a method of recovering additional oil from a reservoir that has been depleted both by primary production and then by waterflooding. A bank of solvent is injected into the reservoir through an injection well. The solvent is followed with the injection of a scavenging and propelling fluid. Oil is withdrawn from the production wells. The solvent consists of a blend of liquid propane and a highly viscous distillate oil. The distillate oil has a true boiling range between 680-1,250$F and a viscosity of 200-6,000 cp at 100$F. The blend consists of 60-90% propane by volume, and the scavenging fluid can be water. (7 claims)

  12. Preferred Waterflood Management Practices for the Spraberry Trend Area

    Energy Technology Data Exchange (ETDEWEB)

    Sizemore, C.M.; Schechter, David S.; Vance, Harold

    2003-03-10

    The objectives of this report was to propose the location of new injection wells, to review wellbore status in Germania unit and to forecast the incremental oil recovery based on waterflooding performance in other waterflood pilot area in order to demonstrate the benefit of waterflooding in Germania unit area.

  13. Viscous fingering with partially miscible fluids

    Science.gov (United States)

    Fu, X.; Cueto-Felgueroso, L.; Juanes, R.

    2015-12-01

    When a less viscous fluid displaces a more viscous fluid, the contrast in viscosity destabilizes the interface between the two fluids, leading to the formation of fingers. Experimental and numerical studies of viscous fingering have focused on fluids that are either fully miscible (e.g. water and glycerol) or perfectly immiscible (e.g. water and oil). In practice, however, the miscibility of two fluids can change appreciably with temperature and pressure, and often falls into the case of partial miscibility, where two fluids have limited solubility in each other (e.g. CO2 and water). Following our recent work for miscible systems (Jha et al., PRL 2011, 2013) and immiscible systems (Cueto-Felgueroso and Juanes, PRL 2012, JFM 2014), here we propose a phase-field model for fluid-fluid displacements in a porous medium, when the two fluids have limited (but nonzero) solubility in one another. In our model, partial miscibility is characterized through the design of the thermodynamic free energy of the two-fluid system. We express the model in dimensionless form and elucidate the key dimensionless groups that control the behavior of the system. We present high-resolution numerical simulations of the model applied to the viscous fingering problem. On one hand, we demonstrate the effect of partial miscibility on the hydrodynamic instability. On the other, we elucidate the role of the degree of fingering on the rate of mutual fluid dissolution. Figure caption: final snapshots in simulations of viscous fingering with a two-fluid system mimicking that of CO2 and water. The colormap corresponds to the concentration of CO2. A band of less viscous gas phase rich in CO2 (red) displaces through the more viscous liquid phase that is undersaturated with CO2 (blue). At the fluid interface, an exchange of CO2 occurs as a result of local chemical potentials that drives the system towards thermodynamic equilibrium. This results in a shrinkage of gas phase as well as a local increase in

  14. Behavior of CO2/water flow in porous media for CO2geological storage.

    Science.gov (United States)

    Jiang, Lanlan; Yu, Minghao; Liu, Yu; Yang, Mingjun; Zhang, Yi; Xue, Ziqiu; Suekane, Tetsuya; Song, Yongchen

    2017-04-01

    A clear understanding of two-phase fluid flow properties in porous media is of importance to CO 2 geological storage. The study visually measured the immiscible and miscible displacement of water by CO 2 using MRI (magnetic resonance imaging), and investigated the factor influencing the displacement process in porous media which were filled with quartz glass beads. For immiscible displacement at slow flow rates, the MR signal intensity of images increased because of CO 2 dissolution; before the dissolution phenomenon became inconspicuous at flow rate of 0.8mLmin -1 . For miscible displacement, the MR signal intensity decreased gradually independent of flow rates, because supercritical CO 2 and water became miscible in the beginning of CO 2 injection. CO 2 channeling or fingering phenomena were more obviously observed with lower permeable porous media. Capillary force decreases with increasing particle size, which would increase permeability and allow CO 2 and water to invade into small pore spaces more easily. The study also showed CO 2 flow patterns were dominated by dimensionless capillary number, changing from capillary finger to stable flow. The relative permeability curve was calculated using Brooks-Corey model, while the results showed the relative permeability of CO 2 slightly decreases with the increase of capillary number. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Financial methods for waterflooding injectate design

    Science.gov (United States)

    Heneman, Helmuth J.; Brady, Patrick V.

    2017-08-08

    A method of selecting an injectate for recovering liquid hydrocarbons from a reservoir includes designing a plurality of injectates, calculating a net present value of each injectate, and selecting a candidate injectate based on the net present value. For example, the candidate injectate may be selected to maximize the net present value of a waterflooding operation.

  16. A study of surfactant-assisted waterflooding

    Energy Technology Data Exchange (ETDEWEB)

    Scamehorn, J F; Harwell, J H

    1990-09-01

    In surfactant-assisted waterflooding, a surfactant slug is injected into a reservoir, followed by a brine spacer, followed by second surfactant slug. The charge on the surfactant in the first slug has opposite sign to that in the second slug. When the two slugs mix in the reservoir, a precipitate or coacervate is formed which plugs the permeable region of the reservoir. Subsequently injected water or brine is forced through the low permeability region of the reservoir, increasing sweep efficiency of the waterflood, compared to a waterflood not using surfactants. In this part of the work, two major tasks are performed. First, core floods are performed with oil present to demonstrate the improvement in incremental oil production, as well as permeability modification. Second, a reservoir simulation model will be proposed to further delineate the optimum strategy for implementation of the surfactant-assisted waterflooding, as well as indicate the reservoir types for which it would be most effective. Surfactants utilized were sodium dodecyl sulfate and dodecyl pyridinium chloride. 44 refs., 17 figs., 3 tabs.

  17. Engineering waterfloods for improved oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Craig, F.F. Jr.

    1973-12-01

    The basis for an engineering design of a waterflood is a prediction of expected performance. The basic data required are (1) rock properties; (2) reservoir fluid characteristics; (3) overall reservoir description; and (4) a measure of the reservoir heterogeneity. These factors, together with judgment of possible flooding patterns, yield the calculated performance when used with a prediction technique. Two basic types of rock properties are (1) those influenced by the rock skeleton along; and (2) those influenced jointly by the rock and reservoir fluids. Reservoir fluid characteristics required for a prediction of reservoir performance consist primarily of oil and water viscosities at reservoir temperature and pressure. The mobility ratio is the single most important characteristic of a waterflood--a combination of rock and fluid properties.

  18. Experimental and simulation determination of minimum miscibility pressure for a Bakken tight oil and different injection gases

    OpenAIRE

    Li, Sheng; Luo, Peng

    2016-01-01

    The effective development of unconventional tight oil formations, such as Bakken, could include CO2 enhanced oil recovery (EOR) technologies with associated benefits of capturing and storing large quantities of CO2. It is important to conduct the gas injection at miscible condition so as to reach maximum recovery efficiency. Therefore, determination of the minimum miscibility pressure (MMP) of reservoir live oil–injection gas system is critical in a miscible gas flooding project design. In th...

  19. Waterflooding pays off in the United Kingdom

    Energy Technology Data Exchange (ETDEWEB)

    Collcott, J.S.

    1973-01-01

    A base map shows the East Midlands oil fields of the U.K. The production from these fields has been overshadowed somewhat by the more glamorous big oil and gas discoveries in the North Sea. However, these numerous highly engineered secondary recovery projects will yield significantly more needed crude during the next decade. During the 1946-1952 period, the total annual UK crude production (all in East Midlands) declined from 80 bpd per well (31 wells) and a peak of 855,000 bbl in 1943 to 4 bpd per well (237 wells) or 327,000 bbl in 1948. It became vital to find some means to increase recovery. The recovery methods lay between water injection and injection of air or inert gas. A study of American practice in the Bradford, Pennsylvania area, where similar sand conditions exist, indicated that efficient waterflooding was the answer. This study describes in detail water injection, development of the waterflood, and other pertinent factors with regard to the projects.

  20. CO2 blood test

    Science.gov (United States)

    Bicarbonate test; HCO3-; Carbon dioxide test; TCO2; Total CO2; CO2 test - serum; Acidosis - CO2; Alkalosis - CO2 ... The CO2 test is most often done as part of an electrolyte or basic metabolic panel. Changes in your ...

  1. Analysis of Microbial Communities in the Oil Reservoir Subjected to CO2-Flooding by Using Functional Genes as Molecular Biomarkers for Microbial CO2 Sequestration

    Directory of Open Access Journals (Sweden)

    Jin-Feng eLiu

    2015-03-01

    Full Text Available Sequestration of CO2 in oil reservoirs is considered to be one of the feasible options for mitigating atmospheric CO2 building up and also for the in situ potential bioconversion of stored CO2 to methane. However, the information on these functional microbial communities and the impact of CO2 storage on them is hardly available. In this paper a comprehensive molecular survey was performed on microbial communities in production water samples from oil reservoirs experienced CO2-flooding by analysis of functional genes involved in the process, including cbbM, cbbL, fthfs, [FeFe]-hydrogenase and mcrA. As a comparison, these functional genes in the production water samples from oil reservoir only experienced water-flooding in areas of the same oil bearing bed were also analyzed. It showed that these functional genes were all of rich diversity in these samples, and the functional microbial communities and their diversity were strongly affected by a long-term exposure to injected CO2. More interestingly, microorganisms affiliated with members of the genera Methanothemobacter, Acetobacterium and Halothiobacillus as well as hydrogen producers in CO2 injected area either increased or remained unchanged in relative abundance compared to that in water-flooded area, which implied that these microorganisms could adapt to CO2 injection and, if so, demonstrated the potential for microbial fixation and conversion of CO2 into methane in subsurface oil reservoirs.

  2. CO2-Neutral Fuels

    NARCIS (Netherlands)

    Goede, A.; van de Sanden, M. C. M.

    2016-01-01

    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

  3. Minimum miscibility pressure from EOS

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, T. [Montana Univ., Butte, MT (United States)

    2000-06-01

    Pressure is the main factor influencing the displacement efficiency of crude oil systems by gas injection. A certain minimum pressure, called Minimum Miscibility Pressure (MMP), is required in order to achieve miscible displacement. MMP is defined as the pressure at which the oil recovery versus pressure curve (generated from the slim-tube test) displays a sharp change in slope, also called the inflection point. The author described a simple, practical method that allows the MMP to be determined. The methodology involved the application of a modified version of the Peng and Robinson Equation of State, used in conjunction with a miscibility function. The Peng and Robinson Equation of State was modified by measured molecular weight and specific gravity of the heptanes-plus fraction for the determination of parameters. The necessary criteria for the prediction of the required injection pressure in miscible gas injection were taken into account in the formulation of the mathematical miscibility function. The demonstration of the use of the miscibility function for the determination of the required conditions for miscible displacement of hydrocarbon systems by gas injection was made. The author validated the methodology through a comparison with numerous experimentally measured minimum miscibility pressure values. The results indicated that the methodology presented by the author is capable of accurately predicting MMP for carbon dioxide and other gases with an absolute average error of 3.4 per cent. 32 refs., 2 tabs., 4 figs.

  4. Chemical Control of Hydrodynamic Instabilities in Partially Miscible Two-layer Systems

    OpenAIRE

    Budroni, Marcello; Riolfo, Luis Atilio; Lemaigre, Lorena; Rossi, Federico; Rustici, Mauro; De Wit, Anne

    2014-01-01

    Hydrodynamic instabilities at the interface between two partially miscible liquids impact numerous applications, including CO2 sequestration in saline aquifers. We introduce here a new laboratory-scale model system on which buoyancy- and Marangoni-driven convective instabilities of such partially miscible two-layer systems can easily be studied. This system consists of the stratification of a pure alkyl formate on top of a denser aqueous solution in the gravitational field. A rich spectrum of...

  5. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Perri, Pasquale R.

    2001-04-04

    This report describes the evaluation, design, and implementation of a DOE funded CO2 pilot project in the Lost Hills Field, Kern County, California. The pilot consists of four inverted (injector-centered) 5-spot patterns covering approximately 10 acres, and is located in a portion of the field, which has been under waterflood since early 1992. The target reservoir for the CO2 pilot is the Belridge Diatomite. The pilot location was selected based on geology, reservoir quality and reservoir performance during the waterflood. A CO2 pilot was chosen, rather than full-field implementation, to investigate uncertainties associated with CO2 utilization rate and premature CO2 breakthrough, and overall uncertainty in the unproven CO2 flood process in the San Joaquin Valley.

  6. CO2-helium and CO2-neon mixtures at high pressures.

    Science.gov (United States)

    Mallick, B; Ninet, S; Le Marchand, G; Munsch, P; Datchi, F

    2013-01-28

    The properties of mixtures of carbon dioxide with helium or neon have been investigated as a function of CO(2) concentration and pressure up to 30 GPa at room temperature. The binary phase diagrams of these mixtures are determined over the full range of CO(2) concentrations using visual observations and Raman scattering measurements. Both diagrams are of eutectic type, with a fluid-fluid miscibility gap for CO(2) concentrations in the range [5, 75] mol. % for He and [8, 55] mol. % for Ne, and a complete separation between the two components in the solid phase. The absence of alloys or stoichiometric compounds for these two binary systems is consistent with the Hume-Rothery rules of hard sphere mixtures. The Raman spectra and x-ray diffraction patterns of solid CO(2) embedded in He or Ne for various initial concentrations have been measured up to 30 GPa and 12 GPa, respectively. The frequencies of the Raman modes and the volume of solid phase I are identical, within error bars, to those reported for 100% CO(2) samples, thus confirming the total immiscibility of CO(2) with He and Ne in the solid phase. These results demonstrate the possibility to perform high-pressure experiments on solid CO(2) under (quasi-)hydrostatic conditions using He or Ne as pressure transmitting medium.

  7. Bulk and Surface Aqueous Speciation of Calcite: Implications for Low-Salinity Waterflooding of Carbonate Reservoirs

    KAUST Repository

    Yutkin, Maxim P.

    2017-08-25

    Low-salinity waterflooding (LSW) is ineffective when reservoir rock is strongly water-wet or when crude oil is not asphaltenic. Success of LSW relies heavily on the ability of injected brine to alter surface chemistry of reservoir crude-oil brine/rock (COBR) interfaces. Implementation of LSW in carbonate reservoirs is especially challenging because of high reservoir-brine salinity and, more importantly, because of high reactivity of the rock minerals. Both features complicate understanding of the COBR surface chemistries pertinent to successful LSW. Here, we tackle the complex physicochemical processes in chemically active carbonates flooded with diluted brine that is saturated with atmospheric carbon dioxide (CO2) and possibly supplemented with additional ionic species, such as sulfates or phosphates. When waterflooding carbonate reservoirs, rock equilibrates with the injected brine over short distances. Injected-brine ion speciation is shifted substantially in the presence of reactive carbonate rock. Our new calculations demonstrate that rock-equilibrated aqueous pH is slightly alkaline quite independent of injected-brine pH. We establish, for the first time, that CO2 content of a carbonate reservoir, originating from CO2-rich crude oil and gas, plays a dominant role in setting aqueous pH and rock-surface speciation. A simple ion-complexing model predicts the calcite-surface charge as a function of composition of reservoir brine. The surface charge of calcite may be positive or negative, depending on speciation of reservoir brine in contact with the calcite. There is no single point of zero charge; all dissolved aqueous species are charge determining. Rock-equilibrated aqueous composition controls the calcite-surface ion-exchange behavior, not the injected-brine composition. At high ionic strength, the electrical double layer collapses and is no longer diffuse. All surface charges are located directly in the inner and outer Helmholtz planes. Our evaluation of

  8. CO2NNIE

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Lewis-Kelham, Edwin

    2015-01-01

    We propose a system for calculating the personalized annual fuel consumption and CO2 emissions from transportation. The system, named CO2NNIE, estimates the fuel consumption on the fastest route between the frequent destinations of the user. The travel time and fuel consumption estimated are based......% of the actual fuel consumption (4.6% deviation on average). We conclude, that the system provides new detailed information on CO2 emissions and fuel consumption for any make and model....

  9. Chemical control of hydrodynamic instabilities in partially miscible two-layer systems

    Science.gov (United States)

    de Wit, A.; Riolfo, L. A.; Lemaigre, L.; Rossi, F.; Rustici, M.; Budroni, M. A.

    2013-11-01

    Hydrodynamic instabilities at the interface between two partially miscible liquids impact numerous applications including sequestration of supercritical liquid CO2 in old petroleum reservoirs or saline aquifers. As an alternative to difficult in situ studies of the related mixing dynamics, we introduce a new laboratory-scale model system on which buoyancy- and Marangoni-driven convective instabilities of partially miscible two-layer systems can easily be studied and controlled in presence or not of chemical reactions. This system consists in the stratification of a pure ester on top of a denser partially miscible aqueous solution in the gravitational field. The rich convective dynamics observed upon partial dissolution of the ester in the water followed by its hydrolysis highlight the specificity of partially miscible systems as compared to fully miscible or immiscible ones, i.e. the possibility to control the convective pattern and the mixing properties by tuning (i) the intrinsic miscibility of the ester in water, (ii) the feedback of the dissolved species on its own miscibility as well as (iii) the composition and reactivity of the aqueous solution with the ester phase.

  10. CO2 laser resurfacing.

    Science.gov (United States)

    Fitzpatrick, R E

    2001-07-01

    The CO2 Laser offers a variety of unique features in resurfacing facial photodamage and acne scarring. These include hemostasis, efficient removal of the epidermis in a single pass, thermally induced tissue tightening, and safe, predictable tissue interaction. Knowledge of these mechanisms will result in the capability of using the CO2 laser effectively and safely whether the goal is superficial or deep treatment.

  11. CO2 uit buitenlucht

    NARCIS (Netherlands)

    Weel, van P.A.; Vanthoor, B.H.E.

    2016-01-01

    The supply of additional CO2 in a greenhouse will be restricted in the future. The concentration in outside air has risen above 400 ppm. This may open the possibility to blow this air through the canopy to increase growth. In this project, the vertical CO2 concentration was measured in a vertical

  12. Hydrodynamic instabilities in miscible fluids

    Science.gov (United States)

    Truzzolillo, Domenico; Cipelletti, Luca

    2018-01-01

    Hydrodynamic instabilities in miscible fluids are ubiquitous, from natural phenomena up to geological scales, to industrial and technological applications, where they represent the only way to control and promote mixing at low Reynolds numbers, well below the transition from laminar to turbulent flow. As for immiscible fluids, the onset of hydrodynamic instabilities in miscible fluids is directly related to the physics of their interfaces. The focus of this review is therefore on the general mechanisms driving the growth of disturbances at the boundary between miscible fluids, under a variety of forcing conditions. In the absence of a regularizing mechanism, these disturbances would grow indefinitely. For immiscible fluids, interfacial tension provides such a regularizing mechanism, because of the energy cost associated to the creation of new interface by a growing disturbance. For miscible fluids, however, the very existence of interfacial stresses that mimic an effective surface tension is debated. Other mechanisms, however, may also be relevant, such as viscous dissipation. We shall review the stabilizing mechanisms that control the most common hydrodynamic instabilities, highlighting those cases for which the lack of an effective interfacial tension poses deep conceptual problems in the mathematical formulation of a linear stability analysis. Finally, we provide a short overview on the ongoing research on the effective, out of equilibrium interfacial tension between miscible fluids.

  13. Co2 injection into oil reservoir associated with structural deformation

    KAUST Repository

    El-Amin, Mohamed

    2012-01-01

    In this work, the problem of structural deformation with two-phase flow of carbon sequestration is presented. A model to simulate miscible CO2 injection with structural deformation in the aqueous phase is established. In the first part of this paper, we developed analytical solution for the problem under consideration with certain types of boundary conditions, namely, Dirichlet and Neumann boundary conditions. The second part concerns to numerical simulation using IMPDES scheme. A simulator based on cell-centered finite difference method is used to solve this equations system. Distributions of CO2 saturation, and horizontal and vertical displacements have been introduced.

  14. Outsourcing CO2 Emissions

    Science.gov (United States)

    Davis, S. J.; Caldeira, K. G.

    2009-12-01

    CO2 emissions from the burning of fossil fuels are the primary cause of global warming. Much attention has been focused on the CO2 directly emitted by each country, but relatively little attention has been paid to the amount of emissions associated with consumption of goods and services in each country. This consumption-based emissions inventory differs from the production-based inventory because of imports and exports of goods and services that, either directly or indirectly, involved CO2 emissions. Using the latest available data and reasonable assumptions regarding trans-shipment of embodied carbon through third-party countries, we developed a global consumption-based CO2 emissions inventory and have calculated associated consumption-based energy and carbon intensities. We find that, in 2004, 24% of CO2 emissions are effectively outsourced to other countries, with much of the developed world outsourcing CO2 emissions to emerging markets, principally China. Some wealthy countries, including Switzerland and Sweden, outsource over half of their consumption-based emissions, with many northern Europeans outsourcing more than three tons of emissions per person per year. The United States is both a big importer and exporter of emissions embodied in trade, outsourcing >2.6 tons of CO2 per person and at the same time as >2.0 tons of CO2 per person are outsourced to the United States. These large flows indicate that CO2 emissions embodied in trade must be taken into consideration when considering responsibility for increasing atmospheric greenhouse gas concentrations.

  15. REFERRED WATERFLOOD MANAGEMENT PRACTICES FOR THE SPRABERRY TREND AREA

    Energy Technology Data Exchange (ETDEWEB)

    C. M. Sizemore; David S. Schechter

    2004-02-13

    This report describes the work performed during the first semi-annual third year of the project, ''Preferred Waterflood Management Practices for the Spraberry Trend Area''. The objective of this project is to significantly increase field-wide production in the Spraberry Trend in a short time frame through the application of preferred practices for managing and optimizing water injection. Our goal is to dispel negative attitudes and lack of confidence in water injection and to document the methodology and results for public dissemination to motivate waterflood expansion in the Spraberry Trend. To achieve this objective, in this period we concentrated our effort on analyzing production and injection data to optimize the reservoir management strategies for Germania Spraberry Unit. This study address the reservoir characterization and monitoring of the waterflooding project and propose alternatives of development of the current and future conditions of the reservoir to improve field performance. This research should serve as a guide for future work in reservoir simulation and can be used to evaluate various scenarios for additional development as well as to optimize the operating practices in the field. The results indicate that under the current conditions, a total of 1.410 million barrels of oil can be produced in the next 20 years through the 64 active wells and suggest that the unit can be successfully flooded with the current injection rate of 1600 BWPD and the pattern consisting of 6 injection wells aligned about 36 degrees respect to the major fracture orientation. In addition, a progress report on GSU waterflood pilot is reported for this period.

  16. New minimum miscibility pressure (MMP) correlation for hydrocarbon miscible injections

    Energy Technology Data Exchange (ETDEWEB)

    Maklavani, A.M.; Vatani, A. [University of Tehran, Tehran (Iran, Islamic Republic of). Faculty of Engineering. Petroleum Engineering Dept.], e-mail: morady.babak@gmail.com; Moradi, B.; Tangsirifard, J. [Iranian Central Oil Fields Co., Tehran (Iran, Islamic Republic of). R and D Dept.

    2010-01-15

    This paper presents a new empirically derived correlation for estimating the minimum miscibility pressure (MMP) required for multi contact miscible (MCM) displacement of reservoir petroleum by hydrocarbon gas flooding. Only few empirical correlations exist for determining the MMP. These correlations are often used to estimate the MMP without considering the composition of the injected gas. On the other hand these correlations are based on a limited set of experimental data which are not quite applicable. In addition, in such correlations the complex condensing/vaporizing displacement process is not regarded. In this study, however, the derived correlation investigates the influence of the vaporizing/condensing drive mechanism and oil and gas composition on gas miscibility pressure. MMP has been correlated with temperature, oil composition and injection gas composition. Their effect on hydrocarbon gas MMP has been documented. MCM process was also modeled by compositional slim tube simulators. The modified Peng-Robison equation of state (PR3) was used to evaluate miscibility conditions. The new correlation is based on regression of widely experimentally measured MMP data in literature and data generated from validated compositional slim tube simulators. By comparing the calculated MMPs from the improved correlation data with currently used correlations and experimentally measured data, it was found that the novel correlation is significantly more accurate than other correlations. (author)

  17. CO2 Huff-n-Puff process in a light oil shallow shelf carbonate reservoir. Annual report, January 1, 1995--December 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Wehner, S.C.; Boomer, R.J.; Cole, R.; Preiditus, J.; Vogt, J.

    1996-09-01

    The application of cyclic CO{sub 2}, often referred to as the CO{sub 2} Huff-n-Puff process, may find its niche in the maturing waterfloods of the Permian Basin. Coupling the CO{sub 2} H-n-P process to miscible flooding applications could provide the needed revenue to sufficiently mitigate near-term negative cash flow concerns in the capital intensive miscible projects. Texaco Exploration & Production Inc. and the U.S. Department of Energy have teamed up in an attempt to develop the CO{sub 2} Huff-n-Puff process in the Grayburg/San Andres formation; a light oil, shallow shelf carbonate reservoir within the Permian Basin. This cost-shared effort is intended to demonstrate the viability of this underutilized technology in a specific class of domestic reservoir. A significant amount of oil reserves are located in carbonate reservoirs. Specifically, the carbonates deposited in shallow shelf (SSC) environments make up the largest percentage of known reservoirs within the Permian Basin of North America. Many of these known resources have been under waterflooding operations for decades and are at risk of abandonment if crude oil recoveries cannot be economically enhanced. The selected site for this demonstration project is the Central Vacuum Unit waterflood in Lea County, New Mexico.

  18. Miscibility Development Computation in Enhanced Oil Recovery by Flare Gas Flooding

    Directory of Open Access Journals (Sweden)

    Tjokorde Walmiki Samadhi

    2012-11-01

    Full Text Available The use of flare gas as injection gas in miscible gas flooding enhanced oil recovery (MGF-EOR presents a potential synergy between oil production improvement and greenhouse gases emission mitigation. This work is a preliminary evaluation of the feasibility of miscible flare gas injection based on phase behavior computations of a model oil (43%n-C5H12 : 57%n-C16H34 and a model flare gas (91%CH4 : 9%C2H6. The computations employed the multiple mixing-cell model with Peng-Robinson and PC-SAFT equations of state, and compared the minimum miscibility pressure (MMP value in the cases of flare gas injection and CO2 injection. For CO2 injection, both equations of state produced MMP values close to the measured value of 10.55 MPa. Flare gas injection MMP values were predicted to be 3.6-4.5 times those of CO2 injection. This very high MMP implies high gas compression costs, and may compromise the integrity of the reservoir. Subsequent studies shall explore the gas-oil miscibility behavior of mixtures of flare gas with intermediate hydrocarbon gases and CO2, in order to identify a suitable approach for rendering flare gas feasible as an injection gas in MGF-EOR.

  19. Capnography: monitoring CO2.

    Science.gov (United States)

    Casey, Georgina

    2015-10-01

    MONITORING RESPIRATORY and metabolic function by using capnography to measure end tidal carbon dioxide is standard practice in anaesthesia. It is also becoming more common in intensive care units and during procedural sedation. End tidal carbon dioxide (EtCO2) monitoring may also be used to assess effectiveness of cardiopulmonary resuscitation. Capnography is now emerging in general medical and surgical wards to monitor respiratory depression in patients using opioid analgesics. Using EtCO2 to monitor respiratory function offers many benefits over pulse oximetry. It is important to understand the differences between these two monitoring methods, and why capnography is increasingly favoured in many situations. An understanding of the physiological processes involved in CO2 excretion allows nurses to use capnography in a safe and meaningful way, while monitoring at-risk patients in acute care.

  20. CO2-strategier

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard

    2008-01-01

    I 2007 henvendte Lyngby-Taarbæk kommunens Agenda 21 koordinator sig til Videnskabsbutikken og spurgte om der var interesse for at samarbejde om CO2-strategier. Da Videnskabsbutikken DTU er en åben dør til DTU for borgerne og deres organisationer, foreslog Videnskabsbutikken DTU at Danmarks...... Naturfredningsforening’s lokalkomité for Lyngby blev en del af samarbejdet for at få borgerne i kommunen involveret i arbejdet med at udvikle strategier for reduktion af CO2. Siden sommeren 2007 har Videnskabsbutikken DTU, Lyngby-Taarbæk kommune og Danmarks Naturfredningsforening i Lyngby-Taarbæk samarbejdet om analyse...... og innovation i forhold til CO2-strategier....

  1. CO2 cycle

    Science.gov (United States)

    Titus, Timothy N.; Byrne, Shane; Colaprete, Anthony; Forget, Francois; Michaels, Timothy I.; Prettyman, Thomas H.

    2017-01-01

    This chapter discusses the use of models, observations, and laboratory experiments to understand the cycling of CO2 between the atmosphere and seasonal Martian polar caps. This cycle is primarily controlled by the polar heat budget, and thus the emphasis here is on its components, including solar and infrared radiation, the effect of clouds (water- and CO2-ice), atmospheric transport, and subsurface heat conduction. There is a discussion about cap properties including growth and regression rates, albedos and emissivities, grain sizes and dust and/or water-ice contamination, and curious features like cold gas jets and araneiform (spider-shaped) terrain. The nature of the residual south polar cap is discussed as well as its long-term stability and ability to buffer atmospheric pressures. There is also a discussion of the consequences of the CO2 cycle as revealed by the non-condensable gas enrichment observed by Odyssey and modeled by various groups.

  2. A Review of CO2-Enhanced Oil Recovery with a Simulated Sensitivity Analysis

    Directory of Open Access Journals (Sweden)

    Mandadige Samintha Anne Perera

    2016-06-01

    Full Text Available This paper reports on a comprehensive study of the CO2-EOR (Enhanced oil recovery process, a detailed literature review and a numerical modelling study. According to past studies, CO2 injection can recover additional oil from reservoirs by reservoir pressure increment, oil swelling, the reduction of oil viscosity and density and the vaporization of oil hydrocarbons. Therefore, CO2-EOR can be used to enhance the two major oil recovery mechanisms in the field: miscible and immiscible oil recovery, which can be further increased by increasing the amount of CO2 injected, applying innovative flood design and well placement, improving the mobility ratio, extending miscibility, and controlling reservoir depth and temperature. A 3-D numerical model was developed using the CO2-Prophet simulator to examine the effective factors in the CO2-EOR process. According to that, in pure CO2 injection, oil production generally exhibits increasing trends with increasing CO2 injection rate and volume (in HCPV (Hydrocarbon pore volume and reservoir temperature. In the WAG (Water alternating gas process, oil production generally increases with increasing CO2 and water injection rates, the total amount of flood injected in HCPV and the distance between the injection wells, and reduces with WAG flood ratio and initial reservoir pressure. Compared to other factors, the water injection rate creates the minimum influence on oil production, and the CO2 injection rate, flood volume and distance between the flood wells have almost equally important influence on oil production.

  3. CO2NSL (Datalogger)

    DEFF Research Database (Denmark)

    Andersen, Sune Sick

    ,1500 street lamps around Copenhagen will be changed for light sources with low power consumption. Technical and Environmental turn down the energy as a part of Copenhagen goal of reducing the citys CO2 emissions by 20 percent by the end of year 2015. But how much power will the new lamps comsume? And can...

  4. CO2-neutral fuels

    Directory of Open Access Journals (Sweden)

    Goede A. P. H.

    2015-01-01

    Full Text Available 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

  5. CO2-neutral fuels

    Science.gov (United States)

    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

  6. Enhanced oil recovery by improved waterflooding. Second annual report

    Energy Technology Data Exchange (ETDEWEB)

    1980-08-01

    Energy Resources Co. Inc. is currently operating a pilot polymer improved waterflood of the Storms Pool, a sandstone reservoir in the Illinois basin. During the second year of the project, progress was made in the laboratory work, field preparation, and computer simulation. Tasks II, VII, and IX, polymer selection, workovers, and model building were completed during 1979. The polymer selected is a xanthan type polysaccharide polymer. Other laboratory work included preliminary testing of biocides and oxygen scavengers. Development of the pilot area continued with the completion of the well workovers and the design and initiation of construction of the injection facility. Preliminary simulation was begun.

  7. PREFERRED WATERFLOOD MANAGEMENT PRACTICES FOR THE SPRABERRY TREND AREA

    Energy Technology Data Exchange (ETDEWEB)

    C. M. Sizemore; David S. Schechter

    2003-08-13

    This report describes the work performed during the second year of the project, ''Preferred Waterflood Management Practices for the Spraberry Trend Area''. The objective of this project is to significantly increase field-wide production in the Spraberry Trend in a short time frame through the application of preferred practices for managing and optimizing water injection. Our goal is to dispel negative attitudes and lack of confidence in water injection and to document the methodology and results for public dissemination to motivate waterflood expansion in the Spraberry Trend. To achieve this objective, in this period we concentrated our effort on characterization of Germania Unit using an analog field ET ODaniel unit and old cased hole neutron. Petrophysical Characterization of the Germania Spraberry units requires a unique approach for a number of reasons--limited core data, lack of modern log data and absence of directed studies within the unit. The need for characterization of the Germania unit has emerged as a first step in the review, understanding and enhancement of the production practices applicable within the unit and the trend area in general. In the absence or lack of the afore mentioned resources, an approach that will rely heavily on previous petrophysical work carried out in the neighboring ET O'Daniel unit (6.2 miles away), and normalization of the old log data prior to conventional interpretation techniques will be used. A log-based rock model has been able to guide successfully the prediction of pay and non-pay intervals within the ET O'Daniel unit, and will be useful if found applicable within the Germania unit. A novel multiple regression technique utilizing non-parametric transformations to achieve better correlations in predicting a dependent variable (permeability) from multiple independent variables (rock type, shale volume and porosity) will also be investigated in this study. A log data base includes digitized

  8. Gas condensate reservoir characterisation for CO2 geological storage

    Science.gov (United States)

    Ivakhnenko, A. P.

    2012-04-01

    During oil and gas production hydrocarbon recovery efficiency is significantly increased by injecting miscible CO2 gas in order to displace hydrocarbons towards producing wells. This process of enhanced oil recovery (EOR) might be used for the total CO2 storage after complete hydrocarbon reservoir depletion. This kind of potential storage sites was selected for detailed studies, including generalised development study to investigate the applicability of CO2 for storages. The study is focused on compositional modelling to predict the miscibility pressures. We consider depleted gas condensate field in Kazakhstan as important target for CO2 storage and EOR. This reservoir being depleted below the dew point leads to retrograde condensate formed in the pore system. CO2 injection in the depleted gas condensate reservoirs may allow enhanced gas recovery by reservoir pressurisation and liquid re-vaporisation. In addition a number of geological and petrophysical parameters should satisfy storage requirements. Studied carbonate gas condensate and oil field has strong seal, good petrophysical parameters and already proven successful containment CO2 and sour gas in high pressure and high temperature (HPHT) conditions. The reservoir is isolated Lower Permian and Carboniferous carbonate platform covering an area of about 30 km. The reservoir contains a gas column about 1.5 km thick. Importantly, the strong massive sealing consists of the salt and shale seal. Sour gas that filled in the oil-saturated shale had an active role to form strong sealing. Two-stage hydrocarbon saturation of oil and later gas within the seal frame were accompanied by bitumen precipitation in shales forming a perfect additional seal. Field hydrocarbon production began three decades ago maintaining a strategy in full replacement of gas in order to maintain pressure of the reservoir above the dew point. This was partially due to the sour nature of the gas with CO2 content over 5%. Our models and

  9. Preparation of a Facilitated Transport Membrane Composed of Carboxymethyl Chitosan and Polyethylenimine for CO2/N2 Separation

    OpenAIRE

    Jiang-Nan Shen; Chang-Chao Yu; Gan-Ning Zeng; Bart van der Bruggen

    2013-01-01

    The miscibility of carboxymethyl chitosan/polyethylenimine (CMCS/PEI) blends was analyzed by FT-IR, TGA and SEM. Defect-free CMCS/PEI blend membranes were prepared with polysulfone (PSf) ultrafiltration membranes as support layer for the separation of CO2/N2 mixtures. The results demonstrate that the CMCS/PEI blend is miscible, due to the hydrogen bonding interaction between the two targeted polymers. For the blended membrane without water, the permeability of CO2 gas is 3.6 × 10−7 cm3 cm−2 s...

  10. PREFERRED WATERFLOOD MANAGEMENT PRACTICES FOR THE SPRABERRY TREND AREA

    Energy Technology Data Exchange (ETDEWEB)

    David S. Schechter

    2004-08-31

    The naturally fractured Spraberry Trend Area is one of the largest reservoirs in the domestic U.S. and is the largest reservoir in area extent in the world. Production from Spraberry sands is found over a 2,500 sq. mile area and Spraberry reservoirs can be found in an eight county area in west Texas. Over 150 operators produce 65,000 barrels of oil per day (bopd) from the Spraberry Trend Area from more than 9,000 production wells. Recovery is poor, on the order of 7-10% due to the profoundly complicated nature of the reservoir, yet billions of barrels of hydrocarbons remain. We estimate over 15% of remaining reserves in domestic Class III reservoirs are in Spraberry Trend Area reservoirs. This tremendous domestic asset is a prime example of an endangered hydrocarbon resource in need of immediate technological advancements before thousands of wells are permanently abandoned. This report describes the final work of the project, ''Preferred Waterflood Management Practices for the Spraberry Trend Area.'' The objective of this project is to significantly increase field-wide production in the Spraberry Trend in a short time frame through the application of preferred practices for managing and optimizing water injection. Our goal is to dispel negative attitudes and lack of confidence in water injection and to document the methodology and results for public dissemination to motivate waterflood expansion in the Spraberry Trend. This objective has been accomplished through research in three areas: (1) detail historical review and extensive reservoir characterization, (2) production data management, and (3) field demonstration. This provides results of the final year of the three-year project for each of the three areas.

  11. Canada -- World leader in hydrocarbon miscible flooding

    Energy Technology Data Exchange (ETDEWEB)

    Mungan, N. [Sproule Associates Limited, Calgary, AB (Canada)

    2002-08-01

    Miscible floods are designed to recover oil that due to capillary forces remain in those parts of the a reservoir that have been swept by injected water, and/or in those parts of the reservoir that having been bypassed, have not been swept at all. Miscible floods are one of three types: (1) direct, or first contact miscible, (2) dynamic, or multi-contact miscible, and (3) high pressure gas drive. This paper provides an overview of the process, outlines the considerations that have to be taken into account in selecting a reservoir, describes the procedures to be followed in determining whether miscibility has occurred, and discusses field applications and Canadian experience with the process. There are a total of 61 Canadian miscible flooding field projects. Of these 39 are vertical and 22 are horizontal floods. More than 90 per cent of the projects have operated at injection pressures in the range of only 15,200 kPa to 19,300 kPa. Eight miscible floods failed, while six applications showed marginal success. Incremental oil recoveries in the 47 successful or partially successful floods ranged from 16 per cent to 44 per cent, equal to oil recoveries obtained with primary recovery followed by water flooding. 5 refs., 1 tab., 1 fig.

  12. Experimental and simulation determination of minimum miscibility pressure for a Bakken tight oil and different injection gases

    Directory of Open Access Journals (Sweden)

    Sheng Li

    2017-03-01

    Full Text Available The effective development of unconventional tight oil formations, such as Bakken, could include CO2 enhanced oil recovery (EOR technologies with associated benefits of capturing and storing large quantities of CO2. It is important to conduct the gas injection at miscible condition so as to reach maximum recovery efficiency. Therefore, determination of the minimum miscibility pressure (MMP of reservoir live oil–injection gas system is critical in a miscible gas flooding project design. In this work, five candidate injection gases, namely CO2, CO2-enriched flue gas, natural gas, nitrogen, and CO2-enriched natural gas, were selected and their MMPs with a Bakken live oil were determined experimentally and numerically. At first, phase behaviour tests were conducted for the reconstituted Bakken live oil and the gases. CO2 outperformed other gases in terms of viscosity reduction and oil swelling. Rising bubble apparatus (RBA determined live oil–CO2 MMP as 11.9 MPa and all other gases higher than 30 MPa. The measured phase behaviour data were used to build and tune an equation-of-state (EOS model, which calculated the MMPs for different live oil-gas systems. The EOS-based calculations indicated that CO2 had the lowest MMP with live oil among the five gases in the study. At last, the commonly-accepted Alston et al. equation was used to calculate live oil–pure CO2 MMP and effect of impurities in the gas phase on MMP change. The Bakken oil–CO2 had a calculated MMP of 10.3 MPa from the Alston equation, and sensitivity analysis showed that slight addition of volatile impurities, particularly N2, can increase MMP significantly.

  13. Forecasting global atmospheric CO2

    Science.gov (United States)

    Agustí-Panareda, A.; Massart, S.; Chevallier, F.; Boussetta, S.; Balsamo, G.; Beljaars, A.; Ciais, P.; Deutscher, N. M.; Engelen, R.; Jones, L.; Kivi, R.; Paris, J.-D.; Peuch, V.-H.; Sherlock, V.; Vermeulen, A. T.; Wennberg, P. O.; Wunch, D.

    2014-11-01

    A new global atmospheric carbon dioxide (CO2) real-time forecast is now available as part of the pre-operational Monitoring of Atmospheric Composition and Climate - Interim Implementation (MACC-II) service using the infrastructure of the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS). One of the strengths of the CO2 forecasting system is that the land surface, including vegetation CO2 fluxes, is modelled online within the IFS. Other CO2 fluxes are prescribed from inventories and from off-line statistical and physical models. The CO2 forecast also benefits from the transport modelling from a state-of-the-art numerical weather prediction (NWP) system initialized daily with a wealth of meteorological observations. This paper describes the capability of the forecast in modelling the variability of CO2 on different temporal and spatial scales compared to observations. The modulation of the amplitude of the CO2 diurnal cycle by near-surface winds and boundary layer height is generally well represented in the forecast. The CO2 forecast also has high skill in simulating day-to-day synoptic variability. In the atmospheric boundary layer, this skill is significantly enhanced by modelling the day-to-day variability of the CO2 fluxes from vegetation compared to using equivalent monthly mean fluxes with a diurnal cycle. However, biases in the modelled CO2 fluxes also lead to accumulating errors in the CO2 forecast. These biases vary with season with an underestimation of the amplitude of the seasonal cycle both for the CO2 fluxes compared to total optimized fluxes and the atmospheric CO2 compared to observations. The largest biases in the atmospheric CO2 forecast are found in spring, corresponding to the onset of the growing season in the Northern Hemisphere. In the future, the forecast will be re-initialized regularly with atmospheric CO2 analyses based on the assimilation of CO2 products retrieved from satellite measurements and

  14. Surface Tension and Fingering of Miscible Interfaces

    Science.gov (United States)

    Abib, Mohammed; Liu, Jian-Bang; Ronney, Paul D.

    1999-01-01

    Experiments on miscible, buoyantly unstable reaction-diffusion fronts and non-reacting displacement fronts in Hele-Shaw cells show a fingering-type instability whose wavelengths (lambda*) are consistent with an interfacial tension (sigma) at the front caused by the change in chemical composition, even though the solutions are miscible in all proportions. In conjunction with the Saffman-Taylor model, the relation sigma = K/tau, where tau is the interface thickness and K approximately equal 4 +/- 2 x 10(exp -6) dyne, enables prediction of our measured values of lambda* as well as results from prior experiments on miscible interfaces. These results indicate that even for miscible fluids, surface tension is generally a more significant factor than diffusion in interfacial stability and flow characteristics.

  15. Miscible, Porous Media Displacements with Density Stratification

    National Research Council Canada - National Science Library

    RIAZ, AMIR; MEIBURG, ECKART

    2004-01-01

    A bstract : High accuracy, three‐dimensional numerical simulations of miscible displacements with gravity override, in both homogeneous and heterogeneous porous media, are discussed for the quarter five‐spot configuration...

  16. CO2 as a refrigerant

    CERN Document Server

    2014-01-01

    A first edition, the IIR guide “CO2 as a Refrigerant” highlights the application of carbon dioxide in supermarkets, industrial freezers, refrigerated transport, and cold stores as well as ice rinks, chillers, air conditioning systems, data centers and heat pumps. This guide is for design and development engineers needing instruction and inspiration as well as non-technical experts seeking background information on a specific topic. Written by Dr A.B. Pearson, a well-known expert in the field who has considerable experience in the use of CO2 as a refrigerant. Main topics: Thermophysical properties of CO2 – Exposure to CO2, safety precautions – CO2 Plant Design – CO2 applications – Future prospects – Standards and regulations – Bibliography.

  17. Calculation of minimum miscibility pressure

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Orr, F.M. [Department of Petroleum Engineering, Stanford University, Mitchell Bldg., Room 360, 94305-2220 Stanford, CA (United States)

    2000-09-01

    A method is described and tested for calculation of minimum miscibility pressure (MMP) that makes use of an analytical theory for one-dimensional, dispersion-free flow of multicomponent mixtures. The theory shows that in a displacement of an oil by a gas with n{sub c} components, the behavior of the displacement is controlled by a sequence of n{sub c}-1 key tie lines. Besides, the tie lines that extend through the initial oil and injection gas compositions, there are n{sub c}-3 tie lines, known as crossover tie lines, that can be found from a set of conditions that require the extensions of the appropriate tie lines to intersect each other. The MMP is calculated as the pressure at which one of the key tie lines becomes a tie line of zero length that is tangent to the critical locus. The numerical approach for solving the tie line intersection equations is described; slim tube test and compositional simulation data reported in the literature are used to show that the proposed approach can be used to calculate MMP accurately for displacements with an arbitrary number of components present.

  18. Enzymes in CO2 Capture

    DEFF Research Database (Denmark)

    Fosbøl, Philip Loldrup; Gladis, Arne; Thomsen, Kaj

    The enzyme Carbonic Anhydrase (CA) can accelerate the absorption rate of CO2 into aqueous solutions by several-fold. It exist in almost all living organisms and catalyses different important processes like CO2 transport, respiration and the acid-base balances. A new technology in the field...... of carbon capture is the application of enzymes for acceleration of typically slow ternary amines or inorganic carbonates. There is a hidden potential to revive currently infeasible amines which have an interesting low energy consumption for regeneration but too slow kinetics for viable CO2 capture. The aim...... of this work is to discuss the measurements of kinetic properties for CA promoted CO2 capture solvent systems. The development of a rate-based model for enzymes will be discussed showing the principles of implementation and the results on using a well-known ternary amine for CO2 capture. Conclusions...

  19. CO2 Sequestration short course

    Energy Technology Data Exchange (ETDEWEB)

    DePaolo, Donald J. [Lawrence Berkeley National Laboratory; Cole, David R [The Ohio State University; Navrotsky, Alexandra [University of California-Davis; Bourg, Ian C [Lawrence Berkeley National Laboratory

    2014-12-08

    Given the public’s interest and concern over the impact of atmospheric greenhouse gases (GHGs) on global warming and related climate change patterns, the course is a timely discussion of the underlying geochemical and mineralogical processes associated with gas-water-mineral-interactions encountered during geological sequestration of CO2. The geochemical and mineralogical processes encountered in the subsurface during storage of CO2 will play an important role in facilitating the isolation of anthropogenic CO2 in the subsurface for thousands of years, thus moderating rapid increases in concentrations of atmospheric CO2 and mitigating global warming. Successful implementation of a variety of geological sequestration scenarios will be dependent on our ability to accurately predict, monitor and verify the behavior of CO2 in the subsurface. The course was proposed to and accepted by the Mineralogical Society of America (MSA) and The Geochemical Society (GS).

  20. Improved Efficiency of Miscible C02 Floods and Enhanced Prospects for C02 Flooding Heterogeneous Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Boyun (Gordon) Guo; David S. Schechter; Jyun-Syung Tsau; Reid B. Grigg; Shih-Hsien (Eric) Chang

    1997-01-23

    A grant, �Improved Efficiency of Miscible CO2 Floods and Enhanced Prospects for CO2 Flooding Heterogeneous Reservoirs,� DOE Contract No. DE-FG26-97BC15047, was awarded and started on June 1, 1997. This project examines three major areas in which CO2 flooding can be improved: fluid and matrix interactions, conformance control/sweep efficiency, and reservoir simulation for improved oil recovery. In this quarter we continued the examination of synergistic effects of mixed surfactant versus single surfactant systems to enhance the properties of foams used for improving oil recovery in CO2 floods. The purpose is to reduce the concentration of surfactants and find less expensive surfactants. Also, we are refining reservoir models to handle the complex relationships of CO2-foam and heterogeneous reservoirs. The third area of our report this quarter comprises the results from experiments on CO2-assisted gravity drainage in naturally fractured oil reservoirs. Two more CO2 core flood experiments have been conducted under reservoir conditions to investigate the effect of pressure on oil recovery efficiency during CO2-assisted gravity drainage.

  1. Study of hydrocarbon miscible solvent slug injection process for improved recovery of heavy oil from Schrader Bluff Pool, Milne Point Unit, Alaska. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    The National Energy Strategy Plan (NES) has called for 900,000 barrels/day production of heavy oil in the mid-1990s to meet our national needs. To achieve this goal, it is important that the Alaskan heavy oil fields be brought to production. Alaska has more than 25 billion barrels of heavy oil deposits. Conoco, and now BP Exploration have been producing from Schrader Bluff Pool, which is part of the super heavy oil field known as West Sak Field. Schrader Bluff reservoir, located in the Milne Point Unit, North Slope of Alaska, is estimated to contain up to 1.5 billion barrels of (14 to 21{degrees}API) oil in place. The field is currently under production by primary depletion; however, the primary recovery will be much smaller than expected. Hence, waterflooding will be implemented earlier than anticipated. The eventual use of enhanced oil recovery (EOR) techniques, such as hydrocarbon miscible solvent slug injection process, is vital for recovery of additional oil from this reservoir. The purpose of this research project was to determine the nature of miscible solvent slug which would be commercially feasible, to evaluate the performance of the hydrocarbon miscible solvent slug process, and to assess the feasibility of this process for improved recovery of heavy oil from Schrader Bluff reservoir. The laboratory experimental work includes: slim tube displacement experiments and coreflood experiments. The components of solvent slug includes only those which are available on the North Slope of Alaska.

  2. Experimental use of internal waterflooding in development of oil fields in Tatar USSR

    Energy Technology Data Exchange (ETDEWEB)

    Kotsyubinskii, V.L.; Mosienko, L.G.; Muslimov, R.Kh.; Oshitko, V.M.

    1970-01-01

    Since 1962, an internal waterflooding pattern has been used in Tatar fields. In this pattern, a single water-injection well is surrounded by a circular battery of producing wells. The injection wells penetrate all the producing horizons. Basic geological requirements for this type of flooding pattern are described. Oil recovery data are given. Since 1962, this flooding procedure recovered an additional 11.8 million tons of oil. In 37% of the wells, a daily oil production increase of 5 to 10 tons was observed, and in 20% of the wells, the average increase was 20 to 40 tons. This type of waterflooding procedure was shown to be economically attractive.

  3. Determination of Minimum Miscibility Pressure in supercritical extractor using oil saturated sample

    DEFF Research Database (Denmark)

    Rudyk, Svetlana Nikolayevna; Søgaard, Erik Gydesen; Abbasi, Waqas A.

    2009-01-01

      The main parameter for determination of the possibilities to enhance oil recovery by e.g. CO2 injection into a specific oil field is the measurement of Minimum Miscibility Pressure (MMP). This pressure is the lowest pressure for which a gas can obtain miscibility through a multi contact process...... with a given oil reservoir at the reservoir temperature. The oil formation to which the process is applied must be operated at or above the MMP. Before field trial this parameter is to be determined at the laboratory which traditionally is done by help of a slim tube or a raising bubble experiments. However...... vessel containing the sample at different increasing pressure levels. The oil displaced in such a way was collected and measured. The volume of extracted oil was plotted against the increasing pressure. The form of the graph is similar to that typically obtained from a slim tube experiment.  Following...

  4. Connecting CO2. Feasibility study CO2 network Southwest Netherlands; Connecting CO2. Haalbaarheidsstudie CO2-netwerk Zuidwest-Nederland

    Energy Technology Data Exchange (ETDEWEB)

    Rutten, M.

    2009-06-10

    An overview is given of supply and demand of CO2 in the region Southwest Netherlands and the regions Antwerp and Gent in Belgium. Also attention is paid to possible connections between these regions [Dutch] Een inventarisatie wordt gegeven van vraag en aanbod van CO2 in de regio Zuidwest- Nederland en de regios Antwerpen en Gent in Belgie. Ook worden mogelijke koppelingen tussen de regios besproken.

  5. Preparation of a Facilitated Transport Membrane Composed of Carboxymethyl Chitosan and Polyethylenimine for CO2/N2 Separation

    Directory of Open Access Journals (Sweden)

    Jiang-Nan Shen

    2013-02-01

    Full Text Available The miscibility of carboxymethyl chitosan/polyethylenimine (CMCS/PEI blends was analyzed by FT-IR, TGA and SEM. Defect-free CMCS/PEI blend membranes were prepared with polysulfone (PSf ultrafiltration membranes as support layer for the separation of CO2/N2 mixtures. The results demonstrate that the CMCS/PEI blend is miscible, due to the hydrogen bonding interaction between the two targeted polymers. For the blended membrane without water, the permeability of CO2 gas is 3.6 × 10−7 cm3 cm−2 s−1 cmHg−1 and the corresponding separation factor for CO2 and N2 gas is about 33 at the pressure of 15.2 cmHg. Meanwhile, the blended membrane with water has the better permselectivity. The blended membrane containing water with PEI content of 30 wt% has the permeance of 6.3 × 10−4 cm3 cm−2 s−1 cmHg−1 for CO2 gas and a separation factor of 325 for CO2/N2 mixtures at the same feed pressure. This indicates that the CO2 separation performance of the CMCS/PEI blend membrane is higher than that of other facilitated transport membranes reported for CO2/N2 mixture separation.

  6. Preparation of a Facilitated Transport Membrane Composed of Carboxymethyl Chitosan and Polyethylenimine for CO2/N2 Separation.

    Science.gov (United States)

    Shen, Jiang-Nan; Yu, Chang-Chao; Zeng, Gan-Ning; van der Bruggen, Bart

    2013-02-07

    The miscibility of carboxymethyl chitosan/polyethylenimine (CMCS/PEI) blends was analyzed by FT-IR, TGA and SEM. Defect-free CMCS/PEI blend membranes were prepared with polysulfone (PSf) ultrafiltration membranes as support layer for the separation of CO(2)/N(2) mixtures. The results demonstrate that the CMCS/PEI blend is miscible, due to the hydrogen bonding interaction between the two targeted polymers. For the blended membrane without water, the permeability of CO(2) gas is 3.6 × 10-7 cm3 cm-2 s-1 cmHg-1 and the corresponding separation factor for CO(2) and N(2) gas is about 33 at the pressure of 15.2 cmHg. Meanwhile, the blended membrane with water has the better permselectivity. The blended membrane containing water with PEI content of 30 wt% has the permeance of 6.3 × 10-4 cm3 cm-2 s-1 cmHg-1 for CO(2) gas and a separation factor of 325 for CO(2)/N(2) mixtures at the same feed pressure. This indicates that the CO(2) separation performance of the CMCS/PEI blend membrane is higher than that of other facilitated transport membranes reported for CO(2)/N(2) mixture separation.

  7. The CO2nnect activities

    Science.gov (United States)

    Eugenia, Marcu

    2014-05-01

    Climate change is one of the biggest challenges we face today. A first step is the understanding the problem, more exactly what is the challenge and the differences people can make. Pupils need a wide competencies to meet the challenges of sustainable development - including climate change. The CO2nnect activities are designed to support learning which can provide pupils the abilities, skills, attitudes and awareness as well as knowledge and understanding of the issues. The project "Together for a clean and healthy world" is part of "The Global Educational Campaign CO2nnect- CO2 on the way to school" and it was held in our school in the period between February and October 2009. It contained a variety of curricular and extra-curricular activities, adapted to students aged from 11 to 15. These activities aimed to develop in students the necessary skills to understanding man's active role in improving the quality of the environment, putting an end to its degrading process and to reducing the effects of climate changes caused by the human intervention in nature, including transport- a source of CO2 pollution. The activity which I propose can be easily adapted to a wide range of age groups and linked to the curricula of many subjects: - Investigate CO2 emissions from travel to school -Share the findings using an international database -Compare and discuss CO2 emissions -Submit questions to a climate- and transport expert -Partner with other schools -Meet with people in your community to discuss emissions from transport Intended learning outcomes for pupils who participate in the CO2nnect campaign are: Understanding of the interconnected mobility- and climate change issue climate change, its causes and consequences greenhouse-gas emissions from transport and mobility the interlinking of social, environmental, cultural and economic aspects of the local transport system how individual choices and participation can contribute to creating a more sustainable development

  8. Reducing cement's CO2 footprint

    Science.gov (United States)

    van Oss, Hendrik G.

    2011-01-01

    The manufacturing process for Portland cement causes high levels of greenhouse gas emissions. However, environmental impacts can be reduced by using more energy-efficient kilns and replacing fossil energy with alternative fuels. Although carbon capture and new cements with less CO2 emission are still in the experimental phase, all these innovations can help develop a cleaner cement industry.

  9. The U.S. Gas Flooding Experience: CO2 Injection Strategies and Impact on Ultimate Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Nunez-Lopez, Vanessa [The University of Texas at Austin; Hosseini, Seyyed; Gil-Egui, Ramon

    2017-09-29

    The Permian Basin in West Texas and southwestern New Mexico has seen 45 years of oil reserve growth through CO2 enhanced oil recovery (CO2 EOR). More than 60 CO2 EOR projects are currently active in the region’s limestone, sandstone and dolomite reservoirs. Water alternating gas (WAG) has been the development strategy of choice in the Permian for several technical and economic reasons. More recently, the technology started to get implemented in the much more porous and permeable clastic depositional systems of the onshore U.S. Gulf Coast. Continued CO2 injection (CGI), as opposed to WAG, was selected as the injection strategy to develop Gulf Coast oil fields, where CO2 injection volumes are significantly larger (up to 6 times larger) than those of the Permian. We conducted a compositional simulation based study with the objective of comparing the CO2 utilization ratios (volume of CO2 injected to produce a barrel of oil) of 4 conventional and novel CO2 injection strategies: (1) continuous gas injection (CGI), (2) water alternating gas (WAG), (3) water curtain injection (WCI), and (4) WAG and WCI combination. These injection scenarios were simulated using the GEM module from the Computer Modeling Group (CMG). GEM is an advanced general equation-of-state compositional simulator, which includes equation of state, CO2 miscible flood, CO2/brine interactions, and complex phase behavior. The simulator is set up to model three fluid phases including water, oil, and gas. Our study demonstrates how the selected field development strategy has a significant impact on the ultimate recovery of CO2-EOR projects, with GCI injection providing maximum oil recovery in absolute volume terms, but with WAG offering a more balanced technical-economical approach.

  10. Evidence of Multi-Component Ion Exchange in Dolomite Formation during Low Salinity Waterflooding

    Science.gov (United States)

    Srisuriyachai, Falan; Meekangwal, Suthida

    2017-12-01

    Low salinity waterflooding is a technique performed in many oil reservoirs around the globe. The technique is simply implemented by injecting water with very low ionic activity compared to formation water into an injection well. The injected water will increase reservoir pressure that is compulsory to drive oil moving toward production well. More than just maintaining reservoir pressure as obtained from conventional waterflooding, low salinity water creates shifting of surface condition, resulting in additional amount of liberated oil. Nevertheless, exact oil recovery mechanisms are still discussed. Among these proposed mechanisms, Multi-component Ion Exchange (MIE) together with wettability alteration is believed to be a major mechanism leading to higher oil recovery compared to conventional waterflooding. In this study, detection of calcium and magnesium ions which are Potential Determining Ions (PDI) for carbonate reservoirs are detected during the coreflood experiment. Dolomite rock sample is used to represent carbonate formation and detection of previously mentioned ions is performed by complexometric titration of the effluents. From the study, it is observed that during conventional waterflooding and low salinity waterflooding at low temperature of 30 degrees Celsius, calcium and magnesium ions in the produced water is increased compared to the amount of these ions in the injected water. This incremental of ions can be explained by the dissolution of calcium and magnesium from dolomite which is chemically composed of calcium magnesium carbonate. At this temperature, the portion of calcium ion is always less than magnesium ion even though the amount of calcium ion is higher than magnesium ion in injected water. However, at higher temperatures which are 50 and 70 degrees Celsius, ratio of calcium and magnesium ions in injected and produced water is reversed. Disappearance of magnesium ion in the effluent is more obvious especially at 70 degrees Celsius and by

  11. Play-level distributions of estimates of recovery factors for a miscible carbon dioxide enhanced oil recovery method used in oil reservoirs in the conterminous United States

    Science.gov (United States)

    Attanasi, E.D.; Freeman, P.A.

    2016-03-02

    In a U.S. Geological Survey (USGS) study, recovery-factor estimates were calculated by using a publicly available reservoir simulator (CO2 Prophet) to estimate how much oil might be recovered with the application of a miscible carbon dioxide (CO2) enhanced oil recovery (EOR) method to technically screened oil reservoirs located in onshore and State offshore areas in the conterminous United States. A recovery factor represents the percentage of an oil reservoir’s original oil in place estimated to be recoverable by the application of a miscible CO2-EOR method. The USGS estimates were calculated for 2,018 clastic and 1,681 carbonate candidate reservoirs in the “Significant Oil and Gas Fields of the United States Database” prepared by Nehring Associates, Inc. (2012).

  12. Fang CO2 med Aminosyrer

    DEFF Research Database (Denmark)

    Lerche, Benedicte Mai

    2010-01-01

    Med såkaldte “carbon capture-teknikker” er det muligt at rense røgen fra kulfyrede kraftværker, således at den er næsten helt fri for drivhusgassen CO2. Kunsten er at gøre processen tilstrækkeligt billig. Et lovende fangstredskab i denne proces er aminosyrer.......Med såkaldte “carbon capture-teknikker” er det muligt at rense røgen fra kulfyrede kraftværker, således at den er næsten helt fri for drivhusgassen CO2. Kunsten er at gøre processen tilstrækkeligt billig. Et lovende fangstredskab i denne proces er aminosyrer....

  13. Dynamics of miscible displacements in round tubes

    Energy Technology Data Exchange (ETDEWEB)

    Meiburg, E.; Maxworthy, T.; Chen, C.Y. [Univ. of Southern California, Los Angeles, CA (United States); Petitjeans, P. [Ecole Superieure de Physique et de Chimie Industrielles, Paris (France)

    1995-12-31

    A combined experimental and numerical investigation of miscible two-phase flow in a capillary tube is reported. The fraction of fluid left behind on the wall is obtained as a function of the Peclet, Atwood, and Froude numbers. Scaling arguments are presented for two distinct flow regimes, dominated by diffusion and convection, respectively. In the latter one, an effective surface tension value can be estimated.

  14. Outsourcing CO2 within China.

    Science.gov (United States)

    Feng, Kuishuang; Davis, Steven J; Sun, Laixiang; Li, Xin; Guan, Dabo; Liu, Weidong; Liu, Zhu; Hubacek, Klaus

    2013-07-09

    Recent studies have shown that the high standard of living enjoyed by people in the richest countries often comes at the expense of CO2 emissions produced with technologies of low efficiency in less affluent, developing countries. Less apparent is that this relationship between developed and developing can exist within a single country's borders, with rich regions consuming and exporting high-value goods and services that depend upon production of low-cost and emission-intensive goods and services from poorer regions in the same country. As the world's largest emitter of CO2, China is a prominent and important example, struggling to balance rapid economic growth and environmental sustainability across provinces that are in very different stages of development. In this study, we track CO2 emissions embodied in products traded among Chinese provinces and internationally. We find that 57% of China's emissions are related to goods that are consumed outside of the province where they are produced. For instance, up to 80% of the emissions related to goods consumed in the highly developed coastal provinces are imported from less developed provinces in central and western China where many low-value-added but high-carbon-intensive goods are produced. Without policy attention to this sort of interprovincial carbon leakage, the less developed provinces will struggle to meet their emissions intensity targets, whereas the more developed provinces might achieve their own targets by further outsourcing. Consumption-based accounting of emissions can thus inform effective and equitable climate policy within China.

  15. Viscous fingering with partially miscible fluids

    Science.gov (United States)

    Fu, Xiaojing; Cueto-Felgueroso, Luis; Juanes, Ruben

    2017-10-01

    Viscous fingering—the fluid-mechanical instability that takes place when a low-viscosity fluid displaces a high-viscosity fluid—has traditionally been studied under either fully miscible or fully immiscible fluid systems. Here we study the impact of partial miscibility (a common occurrence in practice) on the fingering dynamics. Through a careful design of the thermodynamic free energy of a binary mixture, we develop a phase-field model of fluid-fluid displacements in a Hele-Shaw cell for the general case in which the two fluids have limited (but nonzero) solubility into one another. We show, by means of high-resolution numerical simulations, that partial miscibility exerts a powerful control on the degree of fingering: fluid dissolution hinders fingering while fluid exsolution enhances fingering. We also show that, as a result of the interplay between compositional exchange and the hydrodynamic pattern-forming process, stronger fingering promotes the system to approach thermodynamic equilibrium more quickly.

  16. Increasing Waterflood Reserves in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, D.; Koerner, R.; Moos D.; Nguyen, J.; Phillips, C.; Tagbor, K.; Walker, S.

    1999-04-05

    This project used advanced reservoir characterization tools, including the pulsed acoustic cased-hole logging tool, geologic three-dimensional (3-D) modeling software, and commercially available reservoir management software to identify sands with remaining high oil saturation following waterflood. Production from the identified high oil saturated sands was stimulated by recompleting existing production and injection wells in these sands using conventional means as well as a short radius redrill candidate.

  17. Determination of optimum miscible gas injection for Iranian oil reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Javadpour, F. G.; Jamialohmadi, M.; Shadizadeh, S. R.

    1997-12-31

    Results of experimental work to determine miscibility conditions for eight Iranian oil fields were discussed. The experimental work consisted of investigating and simulating new miscibility criteria for slim-tube apparatus. Results of the experimental and simulation runs were compared. Results showed that ternary diagrams are not reliable to predict miscibility conditions. A semi-empirical correlation was then developed which was able to satisfactorily predict the minimum miscibility pressure (MMP) within an acceptable error range. (The average prediction error was 4.9 per cent). 12 refs., 4 tabs., 13 figs.

  18. RODZAJE METOD SEKWESTRACJI CO2

    Directory of Open Access Journals (Sweden)

    Zofia LUBAŃSKA

    Full Text Available Z pojęciem ochrony środowiska wiąże się bardzo szeroko w ostatnim czasie omawiane zagadnienie dotyczące ograniczenia emisji CO2. Konsekwencją globalnych zmian klimatu wywołanego przez ludzi jest wzrost stężenia atmosferycznego gazów cieplarnianych, które powodują nasilający się efekt cieplarniany. Wzrasta na świecie liczba ludności, a co za tym idzie wzrasta konsumpcja na jednego mieszkańca, szczególnie w krajach szeroko rozwiniętych gospodarczo. Protokół z Kioto ściśle określa działania jakie należy podjąć w celu zmniejszenia stężenia dwutlenku węgla w atmosferze. Pomimo maksymalnej optymalizacji procesu spalania paliw kopalnianych wykorzystywanych do produkcji energii, zastosowania odnawialnych źródeł energii zmiana klimatu jest nieunikniona i konsekwentnie będzie postępować przez kolejne dekady. Prognozuje się, że duże znaczenie odegra nowoczesna technologia, która ma za zadanie wychwycenie CO2 a następnie składowanie go w odpowiednio wybranych formacjach geologicznych (CCS- Carbon Capture and Storage. Eksperci są zgodni, że ta technologia w niedalekiej przyszłości stanie się rozwiązaniem pozwalającym ograniczyć ogromną ilość emisji CO2 pochodzącą z procesów wytwarzania energii z paliw kopalnych. Z analiz Raportu IPCC wynika, iż technologia CSS może się przyczynić do ok. 20% redukcji emisji dwutlenku węgla przewidzianej do 2050 roku [3]. Zastosowanie jej napotyka na wiele barier, nie tylko technologicznych i ekonomicznych, ale także społecznych. Inną metodą dającą ujemne źródło emisji CO2 jest możliwość wykorzystania obszarów leśnych o odpowiedniej strukturze drzewostanu. Środkiem do tego celu, oprócz ograniczenia zużycia emisjogennych paliw kopalnych (przy zachowaniu zasad zrównoważonego rozwoju może być intensyfikacja zalesień. Zwiększanie lesistości i prawidłowa gospodarka leśna należy do najbardziej efektywnych sposobów kompensowania

  19. Assessment of potential increased oil production by polymer-waterflood in northern and southern mid-continent oil fields. Progress report for the quarter ending December 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    Six tasks are reported on: geological and engineering study of the DOE-Kewanee polymer-augmented waterflood, review of polymer injection program in this field, evaluation of results of polymer-augmented waterflood in this field, review of geological and engineering characteristics of oil fields now in waterflood as candidates for polymer augmentation, review of fields currently under primary production, and determination of ranges of future increased oil production from the polymer-water process in the project area.

  20. Compositional Modeling for Optimum Design of Water-Alternating CO2-LPG EOR under Complicated Wettability Conditions

    Directory of Open Access Journals (Sweden)

    Jinhyung Cho

    2015-01-01

    Full Text Available The addition of LPG to the CO2 stream leads to minimum miscible pressure (MMP reduction that causes more oil swelling and interfacial tension reduction compared to CO2 EOR, resulting in improved oil recovery. Numerical study based on compositional simulation has been performed to examine the injectivity efficiency and transport behavior of water-alternating CO2-LPG EOR. Based on oil, CO2, and LPG prices, optimum LPG concentration and composition were designed for different wettability conditions. Results from this study indicate how injected LPG mole fraction and butane content in LPG affect lowering of interfacial tension. Interfacial tension reduction by supplement of LPG components leads to miscible condition causing more enhanced oil recovery. The maximum enhancement of oil recovery for oil-wet reservoir is 50% which is greater than 22% for water-wet reservoir. According to the result of net present value (NPV analysis at designated oil, CO2, propane, and butane prices, the optimal injected LPG mole fraction and composition exist for maximum NPV. At the case of maximum NPV for oil-wet reservoir, the LPG fraction is about 25% in which compositions of propane and butane are 37% and 63%, respectively. For water-wet reservoir, the LPG fraction is 20% and compositions of propane and butane are 0% and 100%.

  1. Eigenvalues define conditions of stability in liquid-liquid miscible ...

    African Journals Online (AJOL)

    A miscible displacement process is primarily governed by both convective flow and hydrodynamic dispersion. The proper classification of stability condition in the miscible displacement process is a major requirement for a successful field application of this enhanced crude oil recovery mechanism. This paper derives ...

  2. Passive CO2 concentration in higher plants.

    Science.gov (United States)

    Sage, Rowan F; Khoshravesh, Roxana

    2016-06-01

    Photorespiratory limitations on C3 photosynthesis are substantial in warm, low CO2 conditions. To compensate, certain plants evolved mechanisms to actively concentrate CO2 around Rubisco using ATP-supported CO2 pumps such as C4 photosynthesis. Plants can also passively accumulate CO2 without additional ATP expenditure by localizing the release of photorespired and respired CO2 around Rubisco that is diffusively isolated from peripheral air spaces. Passive accumulation of photorespired CO2 occurs when glycine decarboxylase is localized to vascular sheath cells in what is termed C2 photosynthesis, and through forming sheaths of chloroplasts around the periphery of mesophyll cells. The peripheral sheaths require photorespired CO2 to re-enter chloroplasts where it can be refixed. Passive accumulation of respiratory CO2 is common in organs such as stems, fruits and flowers, due to abundant heterotrophic tissues and high diffusive resistance along the organ periphery. Chloroplasts within these organs are able to exploit this high CO2 to reduce photorespiration. CO2 concentration can also be enhanced passively by channeling respired CO2 from roots and rhizomes into photosynthetic cells of stems and leaves via lacunae, aerenchyma and the xylem stream. Through passive CO2 concentration, C3 species likely improved their carbon economy and maintained fitness during episodes of low atmospheric CO2. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. The CO2 emission registries; De CO2 registers

    Energy Technology Data Exchange (ETDEWEB)

    De Witt Wijnen, H.R. [De Brauw Blackstone Westbroek, Den Haag (Netherlands)

    2004-02-01

    The European Commission has made a first draft available of the Regulation for a standardized and secured system of CO2 -emissions registries. Transactions under the European emissions trading scheme will be settled in accordance with the rules of this Regulation. This article gives a summary of the Regulation and describes the way emissions transactions are going to take place. Any person can open an account in an emissions register. The relation between the Kyoto Protocol and the Regulation is discussed, such as the role of the Commitment Period Reserve. Emission Reductions will not qualify as registered goods under Dutch law, as information on individual accounts will not be made public. [Dutch] Begin november van het vorig jaar heeft de Europese Commissie een concept voor commentaar laten circuleren van een verordening inzake een gestandaardiseerd en beveiligd stelsel van registers (de 'Register Verordening'). Aangezien er op dit moment hard gewerkt wordt aan een wijziging van de Wet milieubeheer in verband met de invoering van een hoofdstuk inzake de handel in emissierechten, lijkt het nuttig om de Register Verordening thans al te bespreken. De Wet milieubeheer zal de Register Verordening hebben te volgen. Bovendien zal kennismaking met de Register Verordening het begrip voor de beoogde werking van de toekomstige Europese emissiehandel vergroten. In dit artikel is mede gebruik gemaakt van wetenswaardigheden opgedaan tijdens een bijeenkomst met de opstellers van de Register Verordening in november 2003.

  4. Investigation of Polyvinyl Chloride and Thermoplastic Polyurethane Waste Blend Miscibility

    Directory of Open Access Journals (Sweden)

    Agnė LAUKAITIENĖ

    2013-12-01

    Full Text Available In this study the miscibility of polyvinyl chloride (PVC and poly-e-caprolactone based thermoplastic polyurethanes (TPU waste blends were investigated by dilute solution viscometry. The miscibility criteria a, Db, DB, and D[h] were used to assess the degree of miscibility of polymers in tetrahydrofuran solution. Also, to assess the miscibility and microstructure of PVC/TPU blends obtained by solution casting have been characterized by X-ray diffraction. The tensile strength and deformability properties varying on the blend composition were determined. It was found that PVC and TPU are partially miscible, their blend is amorphous and show two-phase structure. TPU changes the mechanical behaviour of PVC the blends. Increase of TPU content causes PVC elongation at break increase and tensile strength decreases. DOI: http://dx.doi.org/10.5755/j01.ms.19.4.3145

  5. The ins and outs of CO2

    National Research Council Canada - National Science Library

    Raven, John A; Beardall, John

    2016-01-01

    ...; this article examines what is known and where there are gaps in knowledge. Irreversible decarboxylases produce CO2, and CO2 is the substrate/product of enzymes that act as carboxylases and decarboxylases...

  6. ISLSCP II Globalview: Atmospheric CO2 Concentrations

    Data.gov (United States)

    National Aeronautics and Space Administration — The GlobalView Carbon Dioxide (CO2) data product contains synchronized and smoothed time series of atmospheric CO2 concentrations at selected sites that were created...

  7. CO2 Capture for Cement Technology

    DEFF Research Database (Denmark)

    Pathi, Sharat Kumar

    Production of cement is an energy intensive process and is the source of considerable CO2emissions. Itis estimated that the cement industry contributes around 8% of total global CO2emissions. CO2is oneof the major greenhouse gases. In the atmosphere, the CO2concentration has increased from 310...... ppmvin 1960 to 390 ppmv in 2012, probably due to human activity. A lot of research is being carried out forreducing CO2emissions from large stationary sources. Ofwhich, the carbonate looping process is anew process and has the potential to reduce CO2emissions with lower energy penalties. Most of thework...... performed recently has focused on CO2capture from fossil fuel-based power plants. Inherently,this process is especially suitablefor cement plants, as CaO used for CO2capture is also a majoringredient for clinker production. Thus, a detailed investigation was carried outto study the applicationof...

  8. CO2 Virtual Science Data Environment API

    Data.gov (United States)

    National Aeronautics and Space Administration — The CO2 Virtual Data Environment is a comprehensive effort at bringing together the models, data, and tools necessary to perform research on atmospheric CO2.This...

  9. ISLSCP II Globalview: Atmospheric CO2 Concentrations

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The GlobalView Carbon Dioxide (CO2) data product contains synchronized and smoothed time series of atmospheric CO2 concentrations at selected sites that...

  10. Post waterflood CO{sub 2} miscible flood in light oil fluvial dominated deltaic reservoirs. Second quarterly technical progress report, [January 1, 1995--March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    Production from the Marg Area 1 at Port Neches is averaging 392 barrels of oil per day (BOPD) for this quarter. The production drop is due to fluctuation in both GOR and BS&W on various producing well, coupled with low water injectivity in the reservoir. We were unable to inject any tangible amount of water in the reservoir since late January. Both production and injection problems are currently being evaluated to improve reservoir performance. Well Kuhn (No. 6) was stimulated with 120 MMCF of CO{sub 2}, and was placed on production in February 1, 1995. The well was shut in for an additional month after producing dry CO{sub 2} initially. The well was opened again in early April and is currently producing about 40 BOPD. CO{sub 2} injection averaged 11.3 MMCFD including 4100 MMCFD purchased from Cardox, while water injection averaged 1000 BWPD with most of the injection occurring in the month of January.

  11. Example comparison of minimum miscibility pressure correlations

    Energy Technology Data Exchange (ETDEWEB)

    Elzwi, A. [Department of Mineral Resources and Petroleum Engineering, Univ. of Leoben (Austria)

    2009-03-15

    Enhanced oil recovery (EOR) using gas injection, in particular CO{sub 2}, is one of the most discussed miscible processes in Libya. Many of the giant and super-giant oil fields are becoming mature, and although the recovery factors from primary and secondary recoveries can be as high as sixty percent, the remaining quantities are billions of stock tank barrels of oil. One of the major challenges hindering such projects is the availability of injection CO{sub 2}. Recently after lifting the American sanctions, the country opened to foreign companies for exploration and production investments. Besides oil and gas discoveries, some discoveries of high CO{sub 2} concentrations favoured EOR using CO{sub 2} flooding. This article provides preliminary work and a review of experimental and empirical methods and correlations for predicting CO{sub 2} minimum miscibility pressure, MMP. Using the available slim-tube experiments and conventional fluid analysis, MMP was predicted using eight correlations, and the results were compared to the slim-tube measured MMP, and the deviation was reported as an absolute average error, AAE (%). A Peng-Robinson Equation of State, Pre-EOS, model was set up and calibrated using a subsurface fluid sample. This article will be followed up with a compositional simulation study to investigate flow problems during CO{sub 2} injection in one of the Libyan clastic reservoirs. (orig.)

  12. Carbon Dioxide (CO2) in Blood

    Science.gov (United States)

    ... https://medlineplus.gov/labtests/carbondioxideco2inblood.html Carbon Dioxide (CO2) in Blood To use the sharing features on ... please enable JavaScript. What is a Carbon Dioxide (CO2) Blood Test? Carbon dioxide (CO2) is an odorless, ...

  13. Prognose CO2-emissie glastuinbouw 2020

    NARCIS (Netherlands)

    Velden, van der Nico; Smit, Pepijn

    2016-01-01

    The greenhouse horticulture sector and government agreed in a covenant on a CO2 emission budget
    for 2020. It appeared that the 2014 CO2 emissions were considerably lower than this CO2 emission
    budget. The covenant signatories also agreed that an interim evaluation would be carried out

  14. Forest succession at elevated CO2

    Energy Technology Data Exchange (ETDEWEB)

    Clark, James S.; Schlesinger, William H.

    2002-02-01

    We tested hypotheses concerning the response of forest succession to elevated CO2 in the FACTS-1 site at the Duke Forest. We quantified growth and survival of naturally recruited seedlings, tree saplings, vines, and shrubs under ambient and elevated CO2. We planted seeds and seedlings to augment sample sites. We augmented CO2 treatments with estimates of shade tolerance and nutrient limitation while controlling for soil and light effects to place CO2 treatments within the context of natural variability at the site. Results are now being analyzed and used to parameterize forest models of CO2 response.

  15. Increasing Waterflood Reserves in the Wilmington Oil Field Through Reservoir Characterization and Reservoir Management

    Energy Technology Data Exchange (ETDEWEB)

    Chris Phillips; Dan Moos; Don Clarke; John Nguyen; Kwasi Tagbor; Roy Koerner; Scott Walker

    1997-04-10

    This project is intended to increase recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs. Transferring technology so that it can be applied in other sections of the Wilmington Field and by operators in other slope and basin reservoirs is a primary component of the project.

  16. Induced migration of fines during waterflooding in communicating layer-cake reservoirs

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander

    2011-01-01

    to more crossflow between layers and lowers the water sweep efficiency. However, this ratio facilitates the fluid diversion caused by the fines migration, leading to a more efficient enhanced oil recovery. The positive contribution from the mobility ratio to the increased oil recovery due to fines......The effects of fines migration induced by injection of water with a different salinity than the reservoir brine are incorporated into the upscaling model for waterflooding in a layer cake reservoir with good communication between the layers. Mobilization and re-capturing of the reservoir fines may...... migration seems to be limited....

  17. CO2 clearance by membrane lungs.

    Science.gov (United States)

    Sun, Liqun; Kaesler, Andreas; Fernando, Piyumindri; Thompson, Alex J; Toomasian, John M; Bartlett, Robert H

    2017-10-01

    Commercial membrane lungs are designed to transfer a specific amount of oxygen per unit of venous blood flow. Membrane lungs are much more efficient at removing CO2 than adding oxygen, but the range of CO2 transfer is rarely reported. Commercial membrane lungs were studied with the goal of evaluating CO2 removal capacity. CO2 removal was measured in 4 commercial membrane lungs under standardized conditions. CO2 clearance can be greater than 4 times that of oxygen at a given blood flow when the gas to blood flow ratio is elevated to 4:1 or 8:1. The CO2 clearance was less dependent on surface area and configuration than oxygen transfer. Any ECMO system can be used for selective CO2 removal.

  18. Extraction of stevia glycosides with CO2 + water, CO2 + ethanol, and CO2 + water + ethanol

    Directory of Open Access Journals (Sweden)

    A. Pasquel

    2000-09-01

    Full Text Available Stevia leaves are an important source of natural sugar substitute. There are some restrictions on the use of stevia extract because of its distinctive aftertaste. Some authors attribute this to soluble material other than the stevia glycosides, even though it is well known that stevia glycosides have to some extent a bitter taste. Therefore, the purpose of this work was to develop a process to obtain stevia extract of a better quality. The proposed process includes two steps: i Pretreatment of the leaves by SCFE; ii Extraction of the stevia glycosides by SCFE using CO2 as solvent and water and/or ethanol as cosolvent. The mean total yield for SCFE pretreatment was 3.0%. The yields for SCFE with cosolvent of stevia glycosides were below 0.50%, except at 120 bar, 16°C, and 9.5% (molar of water. Under this condition, total yield was 3.4%. The quality of the glycosidic fraction with respect to its capacity as sweetener was better for the SCFE extract as compared to extract obtained by the conventional process. The overall extraction curves were well described by the Lack extended model.

  19. Miscibility of polymer blends with engineering models

    DEFF Research Database (Denmark)

    Vassilis, Harismiadis; van Bergen, A. R. D.; Goncalves, Ana Saraiva

    1996-01-01

    The miscibility behavior of polymer blends that do not exhibit strong specific interactions is examined. Phase equilibrium calculations are presented with the van der Waals equation of state and three group-contribution models (UNIFAC, Entropic-FV, and GC-Flory). Performance of these models is also...... compared. The van der Waals equation of state was recently shown to accurately correlate and predict vapor-liquid and liquid-liquid equilibria for binary polymer/solvent solutions. In this work, it is demonstrated that it correlates the upper critical solution behavior of polymer blends with excellent......, the upper critical solution temperature can be predicted with an average error of less than 45 degrees C. The van der Waals equation of state can correlate the lower critical solution behavior of polymer blends, using an interaction parameter that is a linear function of temperature. The UNIFAC and Entropic...

  20. On the Spreading of Partially Miscible Liquids.

    Science.gov (United States)

    Santiago-Rosanne, Maria; Vignes-Adler, Michèle; Velarde, Manuel G.

    2001-02-15

    As time proceeds, partially miscible liquids spread as a cap surrounded by a primary film according to power laws, t(n), for both the leading edge (front) and the central cap. The corresponding exponents depend on the thickness, H, of the liquid aqueous substrate and the deviation of concentration from its saturation value, DeltaC=C-C(sat). As long as H is thick enough, here H>/=5 mm, the exponents are n=1/2 and n=1/3 for the front and the central cap, respectively. For thinner layers, H approximately 2 mm, and moderate DeltaC, the spreading is drastically hindered and the measured values can go down to n=0.1, due to the additional friction imposed by the confinement of the convective cells generated by dissolution below the primary film which anchor on the solid surface beneath the liquid substrate. Copyright 2001 Academic Press.

  1. CO2 flux from Javanese mud volcanism

    Science.gov (United States)

    Queißer, M.; Burton, M. R.; Arzilli, F.; Chiarugi, A.; Marliyani, G. I.; Anggara, F.; Harijoko, A.

    2017-06-01

    Studying the quantity and origin of CO2 emitted by back-arc mud volcanoes is critical to correctly model fluid-dynamical, thermodynamical, and geochemical processes that drive their activity and to constrain their role in the global geochemical carbon cycle. We measured CO2 fluxes of the Bledug Kuwu mud volcano on the Kendeng Fold and thrust belt in the back arc of Central Java, Indonesia, using scanning remote sensing absorption spectroscopy. The data show that the expelled gas is rich in CO2 with a volume fraction of at least 16 vol %. A lower limit CO2 flux of 1.4 kg s-1 (117 t d-1) was determined, in line with the CO2 flux from the Javanese mud volcano LUSI. Extrapolating these results to mud volcanism from the whole of Java suggests an order of magnitude total CO2 flux of 3 kt d-1, comparable with the expected back-arc efflux of magmatic CO2. After discussing geochemical, geological, and geophysical evidence we conclude that the source of CO2 observed at Bledug Kuwu is likely a mixture of thermogenic, biogenic, and magmatic CO2, with faulting controlling potential pathways for magmatic fluids. This study further demonstrates the merit of man-portable active remote sensing instruments for probing natural gas releases, enabling bottom-up quantification of CO2 fluxes.

  2. CO2 flux from Javanese mud volcanism.

    Science.gov (United States)

    Queißer, M; Burton, M R; Arzilli, F; Chiarugi, A; Marliyani, G I; Anggara, F; Harijoko, A

    2017-06-01

    Studying the quantity and origin of CO2 emitted by back-arc mud volcanoes is critical to correctly model fluid-dynamical, thermodynamical, and geochemical processes that drive their activity and to constrain their role in the global geochemical carbon cycle. We measured CO2 fluxes of the Bledug Kuwu mud volcano on the Kendeng Fold and thrust belt in the back arc of Central Java, Indonesia, using scanning remote sensing absorption spectroscopy. The data show that the expelled gas is rich in CO2 with a volume fraction of at least 16 vol %. A lower limit CO2 flux of 1.4 kg s-1 (117 t d-1) was determined, in line with the CO2 flux from the Javanese mud volcano LUSI. Extrapolating these results to mud volcanism from the whole of Java suggests an order of magnitude total CO2 flux of 3 kt d-1, comparable with the expected back-arc efflux of magmatic CO2. After discussing geochemical, geological, and geophysical evidence we conclude that the source of CO2 observed at Bledug Kuwu is likely a mixture of thermogenic, biogenic, and magmatic CO2, with faulting controlling potential pathways for magmatic fluids. This study further demonstrates the merit of man-portable active remote sensing instruments for probing natural gas releases, enabling bottom-up quantification of CO2 fluxes.

  3. Porous Organic Polymers for CO2 Capture

    KAUST Repository

    Teng, Baiyang

    2013-05-01

    Carbon dioxide (CO2) has long been regarded as the major greenhouse gas, which leads to numerous negative effects on global environment. The capture and separation of CO2 by selective adsorption using porous materials proves to be an effective way to reduce the emission of CO2 to atmosphere. Porous organic polymers (POPs) are promising candidates for this application due to their readily tunable textual properties and surface functionalities. The objective of this thesis work is to develop new POPs with high CO2 adsorption capacities and CO2/N2 selectivities for post-combustion effluent (e.g. flue gas) treatment. We will also exploit the correlation between the CO2 capture performance of POPs and their textual properties/functionalities. Chapters Two focuses on the study of a group of porous phenolic-aldehyde polymers (PPAPs) synthesized by a catalyst-free method, the CO2 capture capacities of these PPAPs exceed 2.0 mmol/g at 298 K and 1 bar, while keeping CO2/N2 selectivity of more than 30 at the same time. Chapter Three reports the gas adsorption results of different hyper-cross-linked polymers (HCPs), which indicate that heterocyclo aromatic monomers can greatly enhance polymers’ CO2/N2 selectivities, and the N-H bond is proved to the active CO2 adsorption center in the N-contained (e.g. pyrrole) HCPs, which possess the highest selectivities of more than 40 at 273 K when compared with other HCPs. Chapter Four emphasizes on the chemical modification of a new designed polymer of intrinsic microporosity (PIM) with high CO2/N2 selectivity (50 at 273 K), whose experimental repeatability and chemical stability prove excellent. In Chapter Five, we demonstrate an improvement of both CO2 capture capacity and CO2/N2 selectivity by doping alkali metal ions into azo-polymers, which leads a promising method to the design of new porous organic polymers.

  4. Design and Implementation of a CO2 Flood Utilizing Advanced Reservoir Characterization and Horizontal Injection Wells In a Shallow Shelf Carbonate Approaching Waterflood Depletion

    Energy Technology Data Exchange (ETDEWEB)

    Czirr, K.L.; Owen, R.; Robertson, C.R.; Harpole, K.J.; Durrett, E.G.

    1999-11-09

    This project consist of two budget phases. Budget Phase I started in June 1994 and ended late June 1996. During this phase the Reservoir Analysis and Characterization Task and the Advanced Technology Definition Task were completed. Completion of these tasks enabled the project to be designed, and an Authority for Expenditure (AFE) for project implementation to be generated and submitted to the working interest owners for approval. Budget Phase II consists of the implementation and execution of the project in the field.

  5. Field Demonstration of Carbon Dioxide Miscible Flooding in the Lansing-Kansas City Formation, Central Kansas

    Energy Technology Data Exchange (ETDEWEB)

    Alan Byrnes; G. Paul Willhite; Don Green; Martin Dubois; Richard Pancake; Timothy Carr; W. Lynn Watney; John Doveton; Willard Guy; Rodney Reynolds; Dave Murfin; James Daniels; Russell Martin; William Flanders; Dave Vander Griend; Eric Mork; Paul Cantrell

    2007-03-07

    A pilot carbon dioxide miscible flood was initiated in the Lansing Kansas City C formation in the Hall Gurney Field, Russell County, Kansas. The reservoir zone is an oomoldic carbonate located at a depth of about 2900 feet. The pilot consists of one carbon dioxide injection well and three production wells. Continuous carbon dioxide injection began on December 2, 2003. By the end of June 2005, 16.19 MM lb of carbon dioxide were injected into the pilot area. Injection was converted to water on June 21, 2005 to reduce operating costs to a breakeven level with the expectation that sufficient carbon dioxide has been injected to displace the oil bank to the production wells by water injection. By December 31, 2006, 79,072 bbls of water were injected into CO2 I-1 and 3,923 bbl of oil were produced from the pilot. Water injection rates into CO2 I-1, CO2 No.10 and CO2 No.18 were stabilized during this period. Oil production rates increased from 4.7 B/D to 5.5 to 6 B/D confirming the arrival of an oil bank at CO2 No.12. Production from wells to the northwest of the pilot region indicates that oil displaced from carbon dioxide injection was produced from Colliver No.7, Colliver No.3 and possibly Graham A4 located on an adjacent property. There is evidence of a directional permeability trend toward the NW through the pilot region. The majority of the injected carbon dioxide remains in the pilot region, which has been maintained at a pressure at or above the minimum miscibility pressure. Our management plan is to continue water injection maintaining oil displacement by displacing the carbon dioxide remaining in the C zone,. If the decline rate of production from the Colliver Lease remains as estimated and the oil rate from the pilot region remains constant, we estimate that the oil production attributed to carbon dioxide injection will be about 12,000 bbl by December 31, 2007. Oil recovery would be equivalent to 12 MCF/bbl, which is consistent with field experience in

  6. Metal-Organic Framework-Stabilized CO2/Water Interfacial Route for Photocatalytic CO2Conversion.

    Science.gov (United States)

    Luo, Tian; Zhang, Jianling; Li, Wei; He, Zhenhong; Sun, Xiaofu; Shi, Jinbiao; Shao, Dan; Zhang, Bingxing; Tan, Xiuniang; Han, Buxing

    2017-11-29

    Here, we propose a CO 2 /water interfacial route for photocatalytic CO 2 conversion by utilizing a metal-organic framework (MOF) as both an emulsifier and a catalyst. The CO 2 reduction occurring at the CO 2 /water interface produces formate with remarkably enhanced efficiency as compared with that in conventional solvent. The route is efficient, facile, adjustable, and environmentally benign, which is applicable for the CO 2 transformation photocatalyzed by different kinds of MOFs.

  7. Urine as a CO2 absorbent.

    Science.gov (United States)

    Aguilar, Manuel Jiménez

    2012-04-30

    The aim of this work was to investigate the effect of urine on the absorption of greenhouse gases such as CO(2). Human urine diluted with olive-oil-mill wastewaters (OMW) could be used to capture CO(2) from flue gas of coal-fired power plant and convert CO(2) emissions into valuable fertilizers (mainly, NH(4)HCO(3)) that can enhance CO(2) sequestration into soil and subsoil layers. Thus, the CO(2) emissions could be reduced between 0.1 and 1%. The proposed strategy requires further research to increase CO(2) absorption and assess the risks associated with wastewater reuse and xenobiotics in the agroecological environment. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. CO2 Capture by Cement Raw Meal

    DEFF Research Database (Denmark)

    Pathi, Sharat Kumar; Lin, Weigang; Illerup, Jytte Boll

    2013-01-01

    The cement industry is one of the major sources of CO2 emissions and is likely to contribute to further increases in the near future. The carbonate looping process has the potential to capture CO2 emissions from the cement industry, in which raw meal for cement production could be used...... as the sorbent. Cyclic experiments were carried out in a TGA apparatus using industrial cement raw meal and synthetic raw meal as sorbents, with limestone as the reference. The results show that the CO2 capture capacities of the cement raw meal and the synthetic raw meal are comparable to those of pure limestone....... The CO2 capture capacity of limestone in the raw meal is lower than for pure limestone. The difference in the CO2 capture capacity decreases with an increase in cycle number. The calcination conditions and composition are major factors that influence the CO2 capture capacity of limestone. At 850 °C in N2...

  9. Advanced technology development reducing CO2 emissions

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Sup

    2010-09-15

    Responding to Korean government policies on green growth and global energy/ environmental challenges, SK energy has been developing new technologies to reduce CO2 emissions by 1) CO2 capture and utilization, 2) efficiency improvement, and 3) Li-ion batteries. The paper introduces three advanced technologies developed by SK energy; GreenPol, ACO, and Li-ion battery. Contributing to company vision, a more energy and less CO2, the three technologies are characterized as follows. GreenPol utilizes CO2 as a feedstock for making polymer. Advanced Catalytic Olefin (ACO) reduces CO2 emission by 20% and increase olefin production by 17%. Li-ion Batteries for automotive industries improves CO2 emission.

  10. CO2 Hydration Shell Structure and Transformation.

    Science.gov (United States)

    Zukowski, Samual R; Mitev, Pavlin D; Hermansson, Kersti; Ben-Amotz, Dor

    2017-07-06

    The hydration-shell of CO2 is characterized using Raman multivariate curve resolution (Raman-MCR) spectroscopy combined with ab initio molecular dynamics (AIMD) vibrational density of states simulations, to validate our assignment of the experimentally observed high-frequency OH band to a weak hydrogen bond between water and CO2. Our results reveal that while the hydration-shell of CO2 is highly tetrahedral, it is also occasionally disrupted by the presence of entropically stabilized defects associated with the CO2-water hydrogen bond. Moreover, we find that the hydration-shell of CO2 undergoes a temperature-dependent structural transformation to a highly disordered (less tetrahedral) structure, reminiscent of the transformation that takes place at higher temperatures around much larger oily molecules. The biological significance of the CO2 hydration shell structural transformation is suggested by the fact that it takes place near physiological temperatures.

  11. Bosch - An alternate CO2 reduction technology

    Science.gov (United States)

    Heppner, D. B.; Hallick, T. M.; Clark, D. C.; Quattrone, P. D.

    1979-01-01

    The Bosch process is the most promising CO2 reduction concept for future prolonged space missions. The paper presents the design of a three-person-capacity preprototype B-CRS (Bosch-based CO2 Reduction Subsystem). It is sized to reduce 3.0 kg/d CO2 generated by the crew and to supply the product water to an O2 generation subsystem to obtain O2. The design supports future development of the B-CRS as an alternative CO2 reduction subsystem to the Sabatier-based process presently under test at NASA. The discussion covers the Bosch CO2 reduction concept, process and hardware description, performance parameters, design specifications, subsystem schematic and operation, mechanical subsystem summary, control/monitor instrumentation, and subsystem packaging. A B-CRS with a proven technological base is an attractive CO2 reduction subsystem that eliminates overboard venting.

  12. CO2 Activation over Catalytic Surfaces.

    Science.gov (United States)

    Álvarez, Andrea; Borges, Marta; Corral-Pérez, Juan José; Olcina, Joan Giner; Hu, Lingjun; Cornu, Damien; Huang, Rui; Stoian, Dragos; Urakawa, Atsushi

    2017-11-17

    This article describes the main strategies to activate and convert carbon dioxide (CO2 ) into valuable chemicals over catalytic surfaces. Coherent elements such as common intermediates are identified in the different strategies and concisely discussed based on the reactivity of CO2 with the aim to understand the decisive factors for selective and efficient CO2 conversion. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. CO2 Allowance and Electricity Price Interaction

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    With the introduction of CO2 emission constraints on power generators in the European Union, climate policy is starting to have notable effects on energy markets. This paper sheds light on the links between CO2 prices, electricity prices, and electricity costs to industry. It is based on a series of interviews with industrial and electricity stakeholders, as well as a rich literature seeking to estimate the exact effect of CO2 prices on electricity prices.

  14. CO2 capture in different carbon materials.

    Science.gov (United States)

    Jiménez, Vicente; Ramírez-Lucas, Ana; Díaz, José Antonio; Sánchez, Paula; Romero, Amaya

    2012-07-03

    In this work, the CO(2) capture capacity of different types of carbon nanofibers (platelet, fishbone, and ribbon) and amorphous carbon have been measured at 26 °C as at different pressures. The results showed that the more graphitic carbon materials adsorbed less CO(2) than more amorphous materials. Then, the aim was to improve the CO(2) adsorption capacity of the carbon materials by increasing the porosity during the chemical activation process. After chemical activation process, the amorphous carbon and platelet CNFs increased the CO(2) adsorption capacity 1.6 times, whereas fishbone and ribbon CNFs increased their CO(2) adsorption capacity 1.1 and 8.2 times, respectively. This increase of CO(2) adsorption capacity after chemical activation was due to an increase of BET surface area and pore volume in all carbon materials. Finally, the CO(2) adsorption isotherms showed that activated amorphous carbon exhibited the best CO(2) capture capacity with 72.0 wt % of CO(2) at 26 °C and 8 bar.

  15. Global Mapping of CO2 on Enceladus

    Science.gov (United States)

    McCord, T. B.; Combe, J. P.; Matson, D.; Johnson, T. V.

    2014-12-01

    We present the first global map of CO2 on Enceladus. The purpose is to determine whether CO2 is associated to fractures and eruptions, and if it formed recently. Cassini observed tectonic features and plumes on Enceladus, which could be caused by a warm subsurface ocean containing dissolved gases. CO2 should be one of these gases (Postberg F. et al., Nature, 2009), and some of it should be erupted and condensed onto the surface (Matson et al., Icarus, 2012). Validation of this hypothesis could be done by determining the amount, location and molecular state of the CO2. Free CO2 ice and complexed CO2 were reported on Enceladus (Brown et al., Science, 2006; Hansen, LPSC, 2010) from analysis of Cassini Visual and Infrared Mapping Spectrometer (VIMS) data, and on other Saturn icy satellites (Cruikshank et al., Icarus, 2010 ; Filacchione et al., Icarus, 2010). Complexed CO2 has also been found from Galileo Near-Infrared Mapping Spectrometer (NIMS) spectra on the icy Galilean satellites (McCord et al., Science, 1997 and JGR, 1998), apparently due to both interior outgassing and radiation processing. CO2 has an asymmetric stretching mode that creates an absorption band, the wavelength position of which is sensitive to the nature of molecular associations between CO2 and their neighbors. Free CO2 ice absorbs at 4.268 μm for (Sandford and Allamandola, 1990) and CO2 complexed with other molecules absorbs at shorter wavelengths, around 4.25 μm or shorter (Chaban et al., Icarus, 2007). In VIMS spectra of Enceladus, this stretching mode absorption band is near the instrument detection limit. We utilized all VIMS data sets available that had significant spatial resolution to increase the statistics of the observations for any given location and improve the signal to noise. CO2 has also a smaller absorption at 2.7 μm, although it occurs in a range of wavelength that has higher signal-to-noise ratio by several magnitudes, because the surface of Enceladus (mostly H2O ice) has

  16. Experimental Ion Mobility measurements in Ne-CO$_2$ and CO$_2$-N$_2$ mixtures

    CERN Document Server

    Encarnação, P.M.C.C.; Veenhof, R.; Neves, P.N.B.; Santos, F.P.; Trindade, A.M.F.; Borges, F.I.G.M.; Conde, C.A.N.

    2016-01-01

    In this paper we present the experimental results for the mobility, K0, of ions in neon-carbon dioxide (Ne-CO2) and carbon dioxide-nitrogen (CO2-N2) gaseous mixtures for total pressures ranging from 8–12 Torr, reduced electric fields in the 10–25 Td range, at room temperature. Regarding the Ne-CO2 mixture only one peak was observed for CO2 concentrations above 25%, which has been identified as an ion originated in CO2, while below 25% of CO2 a second-small peak appears at the left side of the main peak, which has been attributed to impurities. The mobility values for the main peak range between 3.51 ± 0.05 and 1.07 ± 0.01 cm2V−1s−1 in the 10%-99% interval of CO2, and from 4.61 ± 0.19 to 3.00 ± 0.09 cm2V−1s−1 for the second peak observed (10%–25% of CO2). For the CO2-N2, the time-of-arrival spectra displayed only one peak for CO2 concentrations above 10%, which was attributed to ions originated in CO2, namely CO2+(CO2), with a second peak appearing for CO2 concentrations below 10%. This secon...

  17. Effect of Pore-Scale Heterogeneity and Capillary-Viscous Fingering on Commingled Waterflood Oil Recovery in Stratified Porous Media

    Directory of Open Access Journals (Sweden)

    Emad W. Al-Shalabi

    2016-01-01

    Full Text Available Oil recovery prediction and field pilot implements require basic understanding and estimation of displacement efficiency. Corefloods and glass micromodels are two of the commonly used experimental methods to achieve this. In this paper, waterflood recovery is investigated using layered etched glass micromodel and Berea sandstone core plugs with large permeability contrasts. This study focuses mainly on the effect of permeability (heterogeneity in stratified porous media with no cross-flow. Three experimental setups were designed to represent uniformly stratified oil reservoir with vertical discontinuity in permeability. Waterflood recovery to residual oil saturation (Sor is measured through glass micromodel (to aid visual observation, linear coreflood, and forced drainage-imbibition processes by ultracentrifuge. Six oil samples of low-to-medium viscosity and porous media of widely different permeability (darcy and millidarcy ranges were chosen for the study. The results showed that waterflood displacement efficiencies are consistent in both permeability ranges, namely, glass micromodel and Berea sandstone core plugs. Interestingly, the experimental results show that the low permeability zones resulted in higher ultimate oil recovery compared to high permeability zones. At Sor microheterogeneity and fingering are attributed for this phenomenon. In light of the findings, conformance control is discussed for better sweep efficiency. This paper may be of help to field operators to gain more insight into microheterogeneity and fingering phenomena and their impact on waterflood recovery estimation.

  18. Field Demonstration of Carbon Dioxide Miscible Flooding in the Lansing-Kansas City Formation, Central Kansas

    Energy Technology Data Exchange (ETDEWEB)

    Alan Byrnes; G. Paul Willhite; Don Green; Richard Pancake; JyunSyung Tsau; W. Lynn Watney; John Doveton; Willard Guy; Rodney Reynolds; Dave Murfin; James Daniels; Russell Martin; William Flanders; Dave Vander Griend; Eric Mork; Paul Cantrell

    2010-03-07

    A pilot carbon dioxide miscible flood was initiated in the Lansing Kansas City C formation in the Hall Gurney Field, Russell County, Kansas. The reservoir zone is an oomoldic carbonate located at a depth of about 2900 feet. The pilot consists of one carbon dioxide injection well and three production wells. Continuous carbon dioxide injection began on December 2, 2003. By the end of June 2005, 16.19 MM lb of carbon dioxide was injected into the pilot area. Injection was converted to water on June 21, 2005 to reduce operating costs to a breakeven level with the expectation that sufficient carbon dioxide was injected to displace the oil bank to the production wells by water injection. By March 7,2010, 8,736 bbl of oil were produced from the pilot. Production from wells to the northwest of the pilot region indicates that oil displaced from carbon dioxide injection was produced from Colliver A7, Colliver A3, Colliver A14 and Graham A4 located on adjacent leases. About 19,166 bbl of incremental oil were estimated to have been produced from these wells as of March 7, 2010. There is evidence of a directional permeability trend toward the NW through the pilot region. The majority of the injected carbon dioxide remains in the pilot region, which has been maintained at a pressure at or above the minimum miscibility pressure. Estimated oil recovery attributed to the CO2 flood is 27,902 bbl which is equivalent to a gross CO2 utilization of 4.8 MCF/bbl. The pilot project is not economic.

  19. Transcritical CO2-booster installations for supermarkets; Transkritische CO2-boosterinstallaties bij supermarkten

    Energy Technology Data Exchange (ETDEWEB)

    Berger, M. [ECR Nederland, Hoofddorp (Netherlands); Jongejans, D. [Assumburg Koeltechniek, Uitgeest (Netherlands)

    2010-11-15

    To meet the demand for CO2 installations, Assumburg Refrigeration cooperates with a Swedish partner (Green and Cool), which provides complete CO2 packs, including well-developed software. At the moment Green and Cool now has about one hundred and fifty stores equipped with a transcritical CO2 system. [Dutch] Om aan de vraag naar CO2-installaties te kunnen voldoen, werkt Assumburg Koeltechniekdaar samen met een Zweedse partner (Green and Cool), die complete CO2-packs levert, inclusief goed ontwikkelde software. Green and Cool heeft op dit moment al zo'n honderdvijftig winkels voorzien van een transkritische CO2-installatie.

  20. CO2 capture, transport, storage and utilisation

    NARCIS (Netherlands)

    Brouwer, J.H.

    2013-01-01

    Reducing CO2 emissions requires an integrated CO2 management approach. The dependency between the different industry sectors is higher than commonly acknowledged and covers all areas; capture, transport, storage and utilisation. TNO is one of Europe’s largest independent research organisations and

  1. Recent development of capture of CO2

    CERN Document Server

    Chavez, Rosa Hilda

    2014-01-01

    "Recent Technologies in the capture of CO2" provides a comprehensive summary on the latest technologies available to minimize the emission of CO2 from large point sources like fossil-fuel power plants or industrial facilities. This ebook also covers various techniques that could be developed to reduce the amount of CO2 released into the atmosphere. The contents of this book include chapters on oxy-fuel combustion in fluidized beds, gas separation membrane used in post-combustion capture, minimizing energy consumption in CO2 capture processes through process integration, characterization and application of structured packing for CO2 capture, calcium looping technology for CO2 capture and many more. Recent Technologies in capture of CO2 is a valuable resource for graduate students, process engineers and administrative staff looking for real-case analysis of pilot plants. This eBook brings together the research results and professional experiences of the most renowned work groups in the CO2 capture field...

  2. CO2 Capture with Enzyme Synthetic Analogue

    Energy Technology Data Exchange (ETDEWEB)

    Cordatos, Harry

    2010-11-08

    Overview of an ongoing, 2 year research project partially funded by APRA-E to create a novel, synthetic analogue of carbonic anhydrase and incorporate it into a membrane for removal of CO2 from flue gas in coal power plants. Mechanism background, preliminary feasibility study results, molecular modeling of analogue-CO2 interaction, and program timeline are provided.

  3. Membrane Technologies for CO2 Capture

    NARCIS (Netherlands)

    Simons-Fischbein, K.

    2010-01-01

    This thesis investigates the potential of membrane technology for the effective CO2/CH4 separation. The work focuses on two different membrane processes to accomplish the separation: 1) The use of a gas-liquid membrane contactor for the selective absorption of CO2 from CH4 2) The use of thin, dense

  4. CO2 capture research in the Netherlands

    NARCIS (Netherlands)

    Meerman, J.C.; Kuramochi, T.; Egmond, S. van

    2008-01-01

    The global climate is changing due to human activities. This human‑induced climate change is mainly caused by global emissions of carbon dioxide (CO2) into the atmosphere. Most scientists agree that in order to mitigate climate change, by 2050, global CO2 emissions must be reduced by at least 50%

  5. Iconic CO2 Time Series at Risk

    Energy Technology Data Exchange (ETDEWEB)

    Houweling, S. [SRON Netherlands Institute for Space Research, 3584 CA, Utrecht (Netherlands); Badawy, B. [Max-Planck-Institute for Biogeochemistry, 07745, Jena (Germany); Vermeulen, A.T. [Energieonderzoek Centrum Nederland ECN, 1755 ZG Petten (Netherlands)] [and others

    2012-08-31

    The Mauna Loa CO2 time series is iconic evidence of the effect of human-caused fossil fuel and land-use change emissions on the atmospheric increase of CO2. The continuity of such records depends critically on having stable funding, which is currently threatened by the financial crisis.

  6. Photocatalytic CO2 Activation by Water

    NARCIS (Netherlands)

    Yang, Chieh-Chao

    2011-01-01

    Photocatalytic activation of CO2 and water has potential for producing fuels by conversion of photon energy. However, the low productivity still limits practical application. In this study, the goal was to gain more fundamental insight in CO2 activation, and to provide guidelines for rational design

  7. Toxic emissions and devalued CO2-neutrality

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    friendly effects of substituting wood burning for fossil fuels. With reference to Bent Sørensen's classical work on 'Renewable Energy' the assumption of CO2-neutrality regarding incineration is problematised when applied to plants with long rotation periods as trees. Registered CO2-emissions from wood...

  8. Options for CO2 sequestration in Kuwait

    NARCIS (Netherlands)

    Neele, F.; Vandeweijer, V.; Mayyan, H.; Sharma, S.R.; Kamal, D.

    2017-01-01

    In preparation for future requirements to abate CO2 emission levels, a CO2 storage feasibility study was carried out for the country of Kuwait. At present, no definite plans exist to install capture facilities at the larger emission points in the country; the study presented is one of the first

  9. Monitoring Options for CO2 Storage

    NARCIS (Netherlands)

    Arts, R.; Winthaegen, P.

    2005-01-01

    This chapter provides an overview of various monitoring techniques for CO2 storage that is structured into three categories-instrumentation in a well (monitoring well); instrumentation at the (near) surface (surface geophysical methods); and sampling at the (near) surface measuring CO2

  10. Aqueous ethylenediamine for CO(2) capture.

    Science.gov (United States)

    Zhou, Shan; Chen, Xi; Nguyen, Thu; Voice, Alexander K; Rochelle, Gary T

    2010-08-23

    Aqueous ethylenediamine (EDA) has been investigated as a solvent for CO(2) capture from flue gas. EDA can be used at 12 M (mol kg(-1) H(2)O) with an acceptable viscosity of 16 cP (1 cP=10(-3) Pa s) with 0.48 mol CO(2) per equivalent of EDA. Similar to monoethanolamine (MEA), EDA can be used up to 120 degrees C in a stripper without significant thermal degradation. Inhibitor A will effectively eliminate oxidative degradation. Above 120 degrees C, loaded EDA degrades with the production of its cyclic urea and other related compounds. Unlike piperazine, when exposed to oxidative degradation, EDA does not result in excessive foaming. Over much of the loading range, the CO(2) absorption rate with 12 M EDA is comparable to 7 M MEA. However, at typical rich loading, 12 M EDA absorbs CO(2) 2 times slower than 7 M MEA. The capacity of 12 M EDA is 0.72 mol CO(2)/(kg H(2)O+EDA) (for P(CO(2) )=0.5 to 5 kPa at 40 degrees C), which is about double that of MEA. The apparent heat of CO(2) desorption in EDA solution is 84 kJ mol(-1) CO(2); greater than most other amine systems.

  11. In situ characterization of wettability alteration and displacement mechanisms governing recovery enhancement due to low-salinity waterflooding

    Science.gov (United States)

    Khishvand, M.; Alizadeh, A. H.; Oraki Kohshour, I.; Piri, M.; Prasad, R. S.

    2017-05-01

    A series of micro-scale core-flooding experiments were performed on reservoir core samples at elevated temperature and pressure conditions to develop better insights into wettability alteration and pore-scale displacement mechanisms taking place during low-salinity waterflooding (LSWF). Two individual miniature core samples were cut from a preserved reservoir whole core, saturated to establish initial reservoir fluid saturation conditions, and subsequently waterflooded with low-salinity and high-salinity brines. A third miniature sister core sample was also cut, solvent-cleaned, and subjected to a dynamic wettability restoration process (to reestablish native state wettability) and then a low-salinity waterflood. All samples were imaged during the experiments using a micro-CT scanner to obtain fluid occupancy maps and measure in situ oil-water contact angles. The results of the experiments performed on the preserved core samples show a significantly improved performance of low-salinity waterflooding compared to that of high-salinity waterflooding (HSWF). Pore-scale contact angle measurements provide direct evidence of wettability alteration from weakly oil-wet toward weakly water-wet conditions during LSWF, whereas contact angles measured during HSWF remain unchanged. We believe that the reduction in oil-water contact angles toward increased water-wetness lowers the threshold water pressure needed to displace oil from some medium-sized pore elements. Contact angles measured during the dynamic wettability restoration process show an equilibrium wettability state very similar to the initial one observed in the preserved samples. This indicates that drilling fluid contaminants had a negligible effect on the reservoir rock wettability. The experimental results also reveal similarities between saturation trends for the preserved-LSWF and restored-LSWF tests.

  12. CO2 fluxes near a forest edge

    DEFF Research Database (Denmark)

    Sogachev, Andrey; Leclerc, Monique Y.; Zhang, Gensheng

    2008-01-01

    In contrast with recent advances on the dynamics of the flow at a forest edge, few studies have considered its role on scalar transport and, in particular, on CO2 transfer. The present study addresses the influence of the abrupt roughness change on forest atmosphere CO2 exchange and contrasts...... the concentration and flux fields against those of a uniform forested surface. We use an atmospheric boundary layer two-equation closure model that accounts for the flow dynamics and vertical divergence of CO2 sources/sinks within a plant canopy. This paper characterizes the spatial variation of CO2 fluxes...... as a function of both sources/sinks distribution and the vertical structure of the canopy. Results suggest that the ground source plays a major role in the formation of wave-like vertical CO2 flux behavior downwind of a forest edge, despite the fact that the contribution of foliage sources/sinks changes...

  13. Thermodynamic modeling of CO2 mixtures

    DEFF Research Database (Denmark)

    Bjørner, Martin Gamel

    Knowledge of the thermodynamic properties and phase equilibria of mixtures containing carbon dioxide (CO2) is important in several industrial processes such as enhanced oil recovery, carbon capture and storage, and supercritical extractions, where CO2 is used as a solvent. Despite this importance......, accurate predictions of the thermodynamic properties and phase equilibria of mixtures containing CO2 are challenging with classical models such as the Soave-Redlich-Kwong (SRK) equation of state (EoS). This is believed to be due to the fact, that CO2 has a large quadrupole moment which the classical models...... complicated due to parameter identifiability issues. In an attempt to quantify and illustrate these issues, the uncertainties in the pure compound parameters of CO2 were investigated using qCPA as well as different CPA approaches. The approaches employ between three and five parameters. The uncertainties...

  14. Underwater CO2 Sequestration Program in Korea

    Science.gov (United States)

    Kang, S.; Park, Y.; Choi, S.; Kim, Y.; Hwang, J.; Lee, J.

    2008-12-01

    In Korea an interdisciplinary project on underwater CO2 sequestration has been started. One of the main potential sites for the sequestration is the "DolGoRae (Dolphin)" gas field located over the southwestern part of the East/Japan Sea. We plan to deliver CO2 captured from the largest steel company in Korea (POSCO) to this site through pipe lines. To meet this end, chemical engineers study the behavior of CO2 hydrates, mechanical engineers design the pipe lines and injection systems, geologists and geological engineers survey the geological structure of the potential sites, and oceanographers assess the environmental effects. From a preliminary study, we find that we can store captured CO2 to the gas filed safely. In case the CO2 leaks from the storage site it would move to the north along the Korean coast on the average.

  15. Zinc depolarized electrochemical CO2 concentration

    Science.gov (United States)

    Woods, R. R.; Marshall, R. D.; Schubert, F. H.

    1975-01-01

    Two zinc depolarized electrochemical carbon dioxide concentrator concepts were analytically and experimentally evaluated for portable life support system carbon dioxide (CO2) removal application. The first concept, referred to as the zinc hydrogen generator electrochemical depolarized CO2 concentrator, uses a ZHG to generate hydrogen for direct use in an EDC. The second concept, referred to as the zinc/electrochemical depolarized concentrator, uses a standard EDC cell construction modified for use with the Zn anode. The Zn anode is consumed and subsequently regenerated, thereby eliminating the need to supply H2 to the EDC for the CO2 removal process. The evaluation was based primarily on an analytical evaluation of the two ZnDCs at projected end item performance and hardware design levels. Both ZnDC concepts for PLSS CO2 removal application were found to be noncompetitive in both total equivalent launch weight and individual extravehicular activity mission volume when compared to other candidate regenerable PLSS CO2 scrubbers.

  16. The ins and outs of CO2.

    Science.gov (United States)

    Raven, John A; Beardall, John

    2016-01-01

    It is difficult to distinguish influx and efflux of inorganic C in photosynthesizing tissues; this article examines what is known and where there are gaps in knowledge. Irreversible decarboxylases produce CO2, and CO2 is the substrate/product of enzymes that act as carboxylases and decarboxylases. Some irreversible carboxylases use CO2; others use HCO3(-). The relative role of permeation through the lipid bilayer versus movement through CO2-selective membrane proteins in the downhill, non-energized, movement of CO2 is not clear. Passive permeation explains most CO2 entry, including terrestrial and aquatic organisms with C3 physiology and biochemistry, terrestrial C4 plants and all crassulacean acid metabolism (CAM) plants, as well as being part of some mechanisms of HCO3(-) use in CO2 concentrating mechanism (CCM) function, although further work is needed to test the mechanism in some cases. However, there is some evidence of active CO2 influx at the plasmalemma of algae. HCO3(-) active influx at the plasmalemma underlies all cyanobacterial and some algal CCMs. HCO3(-) can also enter some algal chloroplasts, probably as part of a CCM. The high intracellular CO2 and HCO3(-) pools consequent upon CCMs result in leakage involving CO2, and occasionally HCO3(-). Leakage from cyanobacterial and microalgal CCMs involves up to half, but sometimes more, of the gross inorganic C entering in the CCM; leakage from terrestrial C4 plants is lower in most environments. Little is known of leakage from other organisms with CCMs, though given the leakage better-examined organisms, leakage occurs and increases the energetic cost of net carbon assimilation. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  17. The ins and outs of CO2

    Science.gov (United States)

    Raven, John A.; Beardall, John

    2016-01-01

    It is difficult to distinguish influx and efflux of inorganic C in photosynthesizing tissues; this article examines what is known and where there are gaps in knowledge. Irreversible decarboxylases produce CO2, and CO2 is the substrate/product of enzymes that act as carboxylases and decarboxylases. Some irreversible carboxylases use CO2; others use HCO3 –. The relative role of permeation through the lipid bilayer versus movement through CO2-selective membrane proteins in the downhill, non-energized, movement of CO2 is not clear. Passive permeation explains most CO2 entry, including terrestrial and aquatic organisms with C3 physiology and biochemistry, terrestrial C4 plants and all crassulacean acid metabolism (CAM) plants, as well as being part of some mechanisms of HCO3 – use in CO2 concentrating mechanism (CCM) function, although further work is needed to test the mechanism in some cases. However, there is some evidence of active CO2 influx at the plasmalemma of algae. HCO3 – active influx at the plasmalemma underlies all cyanobacterial and some algal CCMs. HCO3 – can also enter some algal chloroplasts, probably as part of a CCM. The high intracellular CO2 and HCO3 – pools consequent upon CCMs result in leakage involving CO2, and occasionally HCO3 –. Leakage from cyanobacterial and microalgal CCMs involves up to half, but sometimes more, of the gross inorganic C entering in the CCM; leakage from terrestrial C4 plants is lower in most environments. Little is known of leakage from other organisms with CCMs, though given the leakage better-examined organisms, leakage occurs and increases the energetic cost of net carbon assimilation. PMID:26466660

  18. Miscibility Critical Points in Plasma Membranes

    Science.gov (United States)

    Machta, Benjamin; Veatch, Sarah; Papanikolaou, Stefanos; Sethna, James P.

    2009-03-01

    Lipid bilayers surround all cells and are home to a host of proteins and lipids that mediate interactions between the cell and its environment. Recent experimental work has shown that simple membranes composed of three lipid components show complex phase behavior at temperatures in the physiological range. For example, two liquid phases and a gel or solid phase are seen, and a second order phase transition with Ising critical behavior can be reached at a boundary of the liquid-liquid coexistence region [1]. Surprisingly, membrane vesicles isolated from living cells can be tuned with a single parameter (temperature) to criticality [1]. This suggests that cell membranes in vivo sit near miscibility critical points, and may help explain some of the paradoxes associated with putative lipid rafts proposed in other experiments. Here we report on work mapping phase diagrams for the simple membranes utilizing NMR and microscopy data. In addition, we use canonical models of phase transitions to understand the qualitative features of the membranes. Finally we explore ideas from information theory and self organized criticality to understand how and why real cells maintain a membrane near criticality. [1] Honerkamp-Smith, Veatch, and Keller, Biochim Biophys Acta. 2008 (in press)

  19. A usage of CO2 hydrate: convenient method to increase CO2 concentration in culturing algae.

    Science.gov (United States)

    Nakano, Sho; Chang, Kwang-Hyeon; Shijima, Atsushi; Miyamoto, Hiroyuki; Sato, Yukio; Noto, Yuji; Ha, Jin-Yong; Sakamoto, Masaki

    2014-11-01

    The addition of CO2 to algal culture systems can increase algal biomass effectively. Generally, gas bubbling is used to increase CO2 levels in culture systems; however, it is difficult to quantitatively operate to control the concentration using this method. In this study, we tested the usability of CO2 hydrate for phytoplankton culture. Specifically, green algae Pseudokirchneriella subcapitata were cultured in COMBO medium that contained dissolved CO2 hydrate, after which its effects were evaluated. The experiment was conducted according to a general bioassay procedure (OECD TG201). CO2 promoted algae growth effectively (about 2-fold relative to the control), and the decrease in pH due to dissolution of the CO2 in water recovered soon because of photosynthesis. Since the CO2 hydrate method can control a CO2 concentration easily and quantitatively, it is expected to be useful in future applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Dynamics of CO2 fluxes and concentrations during a shallow subsurface CO2 release

    Energy Technology Data Exchange (ETDEWEB)

    Lewicki, J.L.; Hilley, G.E.; Dobeck, L.; Spangler, L.

    2009-09-01

    A field facility located in Bozeman, Montana provides the opportunity to test methods to detect, locate, and quantify potential CO2 leakage from geologic storage sites. From 9 July to 7 August 2008, 0.3 t CO2 d{sup -1} were injected from a 100-m long, {approx}2.5 m deep horizontal well. Repeated measurements of soil CO2 fluxes on a grid characterized the spatio-temporal evolution of the surface leakage signal and quantified the surface leakage rate. Infrared CO2 concentration sensors installed in the soil at 30 cm depth at 0 to 10 m from the well and at 4 cm above the ground at 0 and 5 m from the well recorded surface breakthrough of CO2 leakage and migration of CO2 leakage through the soil. Temporal variations in CO2 concentrations were correlated with atmospheric and soil temperature, wind speed, atmospheric pressure, rainfall, and CO2 injection rate.

  1. Integrated Approach Towards the Application of Horizontal Wells to Improve Waterflooding Performance

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, Mohan; Liner, Chris; Kerr, Dennis

    1999-10-15

    This final report describes the progress during the six year of the project on ''Integrated Approach Towards the Application of Horizontal Wells to Improve Waterflooding Performance.'' This report is funded under the Department of Energy's (DOE's) Class I program which is targeted towards improving the reservoir performance of mature oil fields located in fluvially-dominated deltaic deposits. The project involves using an integrated approach to characterize the reservoir followed by drilling of horizontal injection wells to improve production performance. The project was divided into two budget periods. In the first budget period, many modern technologies were used to develop a detailed reservoir management plan; whereas, in the second budget period, conventional data was used to develop a reservoir management plan. The idea was to determine the cost effectiveness of various technologies in improving the performance of mature oil fields.

  2. A new approach of proration-injection allocation for water-flooding mature oilfields

    Directory of Open Access Journals (Sweden)

    Shuyong Hu

    2015-03-01

    Full Text Available This paper presents a new method of injection-production allocation estimation for water-flooding mature oilfields. The suggested approach is based on logistic growth rate functions and several type-curve matching methods. Using the relationship between these equations, oil production and water injection rate as well as injection-production ratio can be easily forecasted. The calculation procedure developed and outlined in this paper requires very few production data and is easily implemented. Furthermore, an oilfield case has been analyzed. The synthetic and field cases validate the calculation procedure, so it can be accurately used in forecasting production data, and it is important to optimize the whole injection-production system.

  3. Electrocatalytic Alloys for CO2 Reduction.

    Science.gov (United States)

    He, Jingfu; Johnson, Noah J J; Huang, Aoxue; Berlinguette, Curtis P

    2018-01-10

    Electrochemically reducing CO2 using renewable energy is a contemporary global challenge that will only be met with electrocatalysts capable of efficiently converting CO2 into fuels and chemicals with high selectivity. Although many different metals and morphologies have been tested for CO2 electrocatalysis over the last several decades, relatively limited attention has been committed to the study of alloys for this application. Alloying is a promising method to tailor the geometric and electric environments of active sites. The parameter space for discovering new alloys for CO2 electrocatalysis is particularly large because of the myriad products that can be formed during CO2 reduction. In this Minireview, mixed-metal electrocatalyst compositions that have been evaluated for CO2 reduction are summarized. A distillation of the structure-property relationships gleaned from this survey are intended to help in the construction of guidelines for discovering new classes of alloys for the CO2 reduction reaction. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Assessing the potential impact of the CO2 performance ladder on CO2 emission reduction

    NARCIS (Netherlands)

    Kornelis Blok; dr. Martijn Rietbergen

    2013-01-01

    The aim of this research is to assess the potential impact of the CO2 Performance Ladder on CO2 emission reduction. The CO2 Performance Ladder is a new green procurement scheme that has been adopted by several public authorities in the Netherlands; it is a staged certification scheme for energy and

  5. Regenerable Sorbent for CO2 Removal

    Science.gov (United States)

    Alptekin, Gokhan; Jayaraman, Ambal

    2013-01-01

    A durable, high-capacity regenerable sorbent can remove CO2 from the breathing loop under a Martian atmosphere. The system design allows near-ambient temperature operation, needs only a small temperature swing, and sorbent regeneration takes place at or above 8 torr, eliminating the potential for Martian atmosphere to leak into the regeneration bed and into the breathing loop. The physical adsorbent can be used in a metabolic, heat-driven TSA system to remove CO2 from the breathing loop of the astronaut and reject it to the Martian atmosphere. Two (or more) alternating sorbent beds continuously scrub and reject CO2 from the spacesuit ventilation loop. The sorbent beds are cycled, alternately absorbing CO2 from the vent loop and rejecting the adsorbed material into the environment at a high CO2 partial pressure (above 8 torr). The system does not need to run the adsorber at cryogenic temperatures, and uses a much smaller temperature swing. The sorbent removes CO2 via a weak chemical interaction. The interaction is strong enough to enable CO2 adsorption even at 3 to 7.6 torr. However, because the interaction between the surface adsorption sites and the CO2 is relatively weak, the heat input needed to regenerate the sorbent is much lower than that for chemical absorbents. The sorbent developed in this project could potentially find use in a large commercial market in the removal of CO2 emissions from coal-fired power plants, if regulations are put in place to curb carbon emissions from power plants.

  6. Enhanced oil recovery by improved waterflooding. Fourth annual report, October 1980-September 1981. [Illinois

    Energy Technology Data Exchange (ETDEWEB)

    Craig, F.F. III; Passman, F.J.; Burtch, F.W.

    1982-05-01

    Energy Resourcs Co. Inc., and its subcontractor Elf Aquitaine Oil and Gas Company are conducting a 100-acre pilot polymer flood in the Storms Pool Field near Carmi, in White County, Illinois. The project is a cost-sharing venture with the United States Department of Energy (DOE). Preparation for the polymer flood began in September 1977, and the project is scheduled for completion in December 1983. This report reviews progress during the fourth year of performance (October 1980 through September 1981). The Storms Pool, once highly productive, has yielded over 12 million barrels of oil from the Waltersburg formation since its discovery in 1939. The field has been waterflooded for over 20 years and is now largely in stripper production with high watercuts at most producing wells. Material balance and recent electric logs indicate, however, that there is a substantial volume of movable oil still in place, presumably bypassed by the inefficient waterflood. The polymer flood is intended to improve the sweep efficiency, showing that the engineering, management, and financial resources required for such tertiary techniques can be applied to similar fields that might otherwise be abandoned for lack of investment by parties knowledgeable in enhanced oil technology. Preflush injection and polymer injection were both initiated during this period with total polymer injection now standing at 179,453 barrels (or about 6% pore volume). Laboratory testing has continued throughout the year with the emphasis being on field support (troubleshooting field problems and monitoring the field injection and production systems). No evidence of polymer break-through has been detected at the production wells. Details of the interference testing program and the radiotracer study executed during this period are also presented.

  7. Energy Balance of Global CO_2 Recycling and Amounts of Reduction of CO_2 Emission

    OpenAIRE

    Hashimoto, K; Akiyama, E.; Habazaki, H.; Kawashima, A.; Komori, M.; SHIMAMURA, K.; Kumagai, N.

    1997-01-01

    On the basis of tailoring of amorphous alloy electrodes for seawater electrolysis to form H_2 and amorphous alloy catalysts for conversion of CO_2 to CH_4, we are proposing global CO_2 recycling : At deserts; power generation by solar energy, at coasts close to the deserts; production of H_2 by electrolysis of seawater, production of CH_4 by the reaction of H_2 and CO_2 transported, and at energy consuming districts; combustion of CH_4, recovery of CO_2 and transportation of liquefied CO_2 to...

  8. A cost effective CO2 strategy

    DEFF Research Database (Denmark)

    In January 2008 the Danish Government decided to prepare a strategy for reducing CO2 from the transport sector in Denmark. The decision to prepare the strategy was part of the follow-up to the national Infrastructure Commission report of January 2008. The preparations have been chaired...... by the Ministry of Transport, with the Technical University of Denmark as one of the main contributors. The CO2-strategy was to be based on the principle of cost-effectiveness. A model was set up to assist in the assessment. The model consists of a projection of CO2-emissions from road and rail modes from 2020......, a scenario-part and a cost-benefit part. Air and sea modes are not analyzed. The model adopts a bottom-up approach to allow a detailed assessment of transport policy measures. Four generic areas of intervention were identified and the likely effect on CO2 emissions, socioeconomic efficiency and other...

  9. The ATLAS IBL CO2 Cooling System

    CERN Document Server

    Verlaat, Bartholomeus; The ATLAS collaboration

    2016-01-01

    The Atlas Pixel detector has been equipped with an extra B-layer in the space obtained by a reduced beam pipe. This new pixel detector called the ATLAS Insertable B-Layer (IBL) is installed in 2014 and is operational in the current ATLAS data taking. The IBL detector is cooled with evaporative CO2 and is the first of its kind in ATLAS. The ATLAS IBL CO2 cooling system is designed for lower temperature operation (<-35⁰C) than the previous developed CO2 cooling systems in High Energy Physics experiments. The cold temperatures are required to protect the pixel sensors for the high expected radiation dose up to 550 fb^-1 integrated luminosity. This paper describes the design, development, construction and commissioning of the IBL CO2 cooling system. It describes the challenges overcome and the important lessons learned for the development of future systems which are now under design for the Phase-II upgrade detectors.

  10. Sustainable Process Networks for CO2 Conversion

    DEFF Research Database (Denmark)

    Frauzem, Rebecca; Kongpanna, P.; Pavarajam, V.

    that are thermodynamically feasible, including the co-reactants, catalysts, operating conditions and reactions. Research has revealed that there are a variety of reactions that fulfill the aforementioned criteria. The products that are formed fall into categories: fuels, bulk chemicals and specialty chemicals. While fuels...... the emissions is the conversion of CO2 into useful products, such as methanol [3]. In this work, through a computer-aided framework for process network synthesis-design, a network of feasible conversion processes that all use emitted CO2 is investigated. CO2 is emitted into the environment from various sources......, such as methanol (MeOH) have the largest market, this network will include a variety of thermodynamically feasible conversion paths [4]. From reviews of work previously done, there are ranges of possible products that are formed from CO2 and another co-reactant directly. Methanol, dimethyl ether, dimethyl...

  11. CO2 Removal from Mars EMU Project

    Data.gov (United States)

    National Aeronautics and Space Administration — CO2 control for during ExtraVehicular Activity (EVA) on mars is challenging. Lithium hydroxide (LiOH) canisters have impractical logistics penalties, and regenerable...

  12. Compact, High Accuracy CO2 Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovative Research Phase I proposal seeks to develop a low cost, robust, highly precise and accurate CO2 monitoring system. This system will...

  13. Compact, High Accuracy CO2 Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovative Research Phase II proposal seeks to develop a low cost, robust, highly precise and accurate CO2 monitoring system. This system will...

  14. CO2 emissions in the steel industry

    Directory of Open Access Journals (Sweden)

    M. Kundak

    2009-07-01

    Full Text Available Global CO2 emissions caused by the burning of fossil fuels over the past century are presented. Taking into consideration the total world production of more than 1,3 billion tons of steel, the steel industry produces over two billion tons of CO2. Reductions in CO2 emissions as a result of technological improvements and structural changes in steel production in industrialized countries during the past 40 years are described. Substantial further reductions in those emissions will not be possible using conventional technologies. Instead, a radical cutback may be achieved if, instead of carbon, hydrogen is used for direct iron ore reduction. The cost and the ensuing CO2 generation in the production of hydrogen as a reducing agent from various sources are analysed.

  15. Photocatalytic Conversion of CO2 on Mars

    Science.gov (United States)

    Meier, Annie; Hare, Bryan

    2016-01-01

    Light on Mars shows potential for providing the energy means necessary for enhanced In-Situ Resource Utilization (ISRU). Through photocatalysis, the energy barrier required to convert CO2 is lowered and CH4 production is favorable.

  16. CO2 Removal from Mars EMU Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A practical CO2 control system for ExtraVehicular Activity (EVA) on Mars have not yet been developed. TDA Research, Inc. proposes to develop a durable,...

  17. CO2 binding in the (quinoline-CO2)- anionic complex

    Science.gov (United States)

    Graham, Jacob D.; Buytendyk, Allyson M.; Wang, Yi; Kim, Seong K.; Bowen, Kit H.

    2015-06-01

    We have studied the (quinoline-CO2)- anionic complex by a combination of mass spectrometry, anion photoelectron spectroscopy, and density functional theory calculations. The (quinoline-CO2)- anionic complex has much in common with previously studied (N-heterocycle-CO2)- anionic complexes both in terms of geometric structure and covalent bonding character. Unlike the previously studied N-heterocycles, however, quinoline has a positive electron affinity, and this provided a pathway for determining the binding energy of CO2 in the (quinoline-CO2)- anionic complex. From the theoretical calculations, we found CO2 to be bound within the (quinoline-CO2)- anionic complex by 0.6 eV. We also showed that the excess electron is delocalized over the entire molecular framework. It is likely that the CO2 binding energies and excess electron delocalization profiles of the previously studied (N-heterocycle-CO2)- anionic complexes are quite similar to that of the (quinoline-CO2)- anionic complex. This class of complexes may have a role to play in CO2 activation and/or sequestration.

  18. A lipophilic ionic liquid based on formamidinium cations and TFSI: the electric response and the effect of CO2 on the conductivity mechanism.

    Science.gov (United States)

    Bertasi, Federico; Giffin, Guinevere A; Vezzù, Keti; Pace, Giuseppe; Abu-Lebdeh, Yaser; Armand, Michel; Di Noto, Vito

    2017-10-04

    This work describes the preparation of the new lipophilic ionic liquid tetraoctyl-formamidinium bis(trifluoromethanesulfonyl) imide (TOFATFSI), which is miscible with lower alkanes. In particular, this work focuses on the electric behaviour of TOFATFSI in the particularly challenging highly apolar environment of supercritical CO2. The conductivity and relaxation phenomena are revealed through the analysis of the broadband electric spectra with a particular emphasis on the effect of temperature and CO2 uptake on the IL conductivity. It is found that temperature boosts the conductivity via an increase in the charge carrier mobility. Also, CO2 absorption affects both the conductivity and the permittivity of the material due to the presence of CO2-IL interactions that modulate the nanostructure and the size of the TOFATFSI aggregates, which increases both the mobility and the density of the charge carriers.

  19. Udvikling af CO2 neutralt byrumsarmatur

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Dam-Hansen, Carsten; Corell, Dennis Dan

    Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet ” Udvikling af CO2 neutralt byrumsarmatur” og udgør slutrapportering for dette projekt.......Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet ” Udvikling af CO2 neutralt byrumsarmatur” og udgør slutrapportering for dette projekt....

  20. Bifunctional Catalysts for CO2 Reduction

    Science.gov (United States)

    2014-09-30

    product distribution as a function of catalyst composition (ligand, metal ions), electrolyte, acid and CO2 pressure. 4. Examine reaction chemistry ...alternative ligand platforms to seek transition metal complexes that would feature inner-sphere reduction chemistry with CO2 and promote the desired multi...into these polyamine based-ligands typically involves a transamination reaction with metal-amide or organometallic starting materials (e.g., M2(N

  1. Density of aqueous solutions of CO2

    OpenAIRE

    Garcia, Julio E.

    2001-01-01

    In this report, we present a numerical representation for the partial molar volume of CO2 in water and the calculation of the corresponding aqueous solution density. The motivation behind this work is related to the importance of having accurate representations for aqueous phase properties in the numerical simulation of carbon dioxide disposal into aquifers as well as in geothermal applications. According to reported experimental data the density of aqueous solutions of CO2 can be as mu...

  2. Photoacoustic CO2-Sensor for Automotive Applications

    OpenAIRE

    Huber, J; C. Weber; Eberhardt, A.; Wöllenstein, J.

    2016-01-01

    We present a field-tested miniaturized spectroscopic CO2 sensor which is based on the photoacoustic effect. The sensor is developed for automotive applications and considers the requirements for the usage in vehicles. The sensor measures two measurement ranges simultaneously: The monitoring of the indoor air quality and the detection of possible leakages of the coolant in CO2 air-conditioning systems. The sensor consists of a miniaturized innovative photoacoustic sensor unit with integrated e...

  3. Combustion of hythane diluted with CO2

    Directory of Open Access Journals (Sweden)

    Hraiech Ibtissem

    2015-01-01

    Full Text Available With increasing concern about energy shortage and environmental protection, improving engine fuel economy and reducing exhaust emissions have become major research topics in combustion and engine development. Hythane (a blend of hydrogen H2 and natural gas NG has generated a significant interest as an alternative fuel for the future. This paper describes an experimental study of the effects of CO2 addition on the stability of a turbulent jet diffusion NG-H2 flame. The mole fraction of hydrogen (% H2 in NG-H2 mixture was varied from 0% to 50%. The equivalence ratio of the hythane/CO2/air mixture was kept at stoichiometry. The results show that the lift-off height increases with the addition of CO2 at various % H2 content in hythane. However, we observe that with 20% H2, we can obtain a stable flame diluted with 40% CO2, while for 0% H2, the flame is blown out above 20% CO2. This means that the limits of flame blowing out are pushed with the additions of H2. Moreover, the results show that for %H2 content in NG-H2 fuel up to 10%, the addition of CO2 could produce lifted flame if the % CO2 is low. At higher % CO2 dilution, flame would remain attached until blow-out. This is mainly due to the fact that the dilution leads to ejection velocities very high but reactivity of the mixture does not change so the flame tends to stretch.

  4. Density of aqueous solutions of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Julio E.

    2001-10-10

    In this report, we present a numerical representation for the partial molar volume of CO2 in water and the calculation of the corresponding aqueous solution density. The motivation behind this work is related to the importance of having accurate representations for aqueous phase properties in the numerical simulation of carbon dioxide disposal into aquifers as well as in geothermal applications. According to reported experimental data the density of aqueous solutions of CO2 can be as much as 2-3% higher than pure water density. This density variation might produce an influence on the groundwater flow regime. For instance, in geologic sequestration of CO2, convective transport mixing might occur when, several years after injection of carbon dioxide has stopped, the CO2-rich gas phase is concentrated at the top of the formation, just below an overlaying caprock. In this particular case the heavier CO2 saturated water will flow downward and will be replaced by water with a lesser CO2 content.

  5. CO2 efflux from cleared mangrove peat.

    Directory of Open Access Journals (Sweden)

    Catherine E Lovelock

    Full Text Available BACKGROUND: CO(2 emissions from cleared mangrove areas may be substantial, increasing the costs of continued losses of these ecosystems, particularly in mangroves that have highly organic soils. METHODOLOGY/PRINCIPAL FINDINGS: We measured CO(2 efflux from mangrove soils that had been cleared for up to 20 years on the islands of Twin Cays, Belize. We also disturbed these cleared peat soils to assess what disturbance of soils after clearing may have on CO(2 efflux. CO(2 efflux from soils declines from time of clearing from ∼10,600 tonnes km(-2 year(-1 in the first year to 3000 tonnes km(2 year(-1 after 20 years since clearing. Disturbing peat leads to short term increases in CO(2 efflux (27 umol m(-2 s(-1, but this had returned to baseline levels within 2 days. CONCLUSIONS/SIGNIFICANCE: Deforesting mangroves that grow on peat soils results in CO(2 emissions that are comparable to rates estimated for peat collapse in other tropical ecosystems. Preventing deforestation presents an opportunity for countries to benefit from carbon payments for preservation of threatened carbon stocks.

  6. Anthropogenic CO2 in the ocean

    Directory of Open Access Journals (Sweden)

    Tsung-Hung Peng

    2005-06-01

    Full Text Available The focus of this review article is on the anthropogenic CO2 taken up by the ocean. There are several methods of identifying the anthropogenic CO2 signal and quantifying its inventory in the ocean. The ?C* method is most frequently used to estimate the global distribution of anthropogenic CO2 in the ocean. Results based on analysis of the dataset obtained from the comprehensive surveys of inorganic carbon distribution in the world oceans in the 1990s are given. These surveys were jointly conducted during the World Ocean Circulation Experiment (WOCE and the Joint Global Ocean Flux Study (JGOFS. This data set consists of 9618 hydrographic stations from a total of 95 cruises, which represents the most accurate and comprehensive view of the distribution of inorganic carbon in the global ocean available today. The increase of anthropogenic CO2 in the ocean during the past few decades is also evaluated using direct comparison of results from repeat surveys and using statistical method of Multi-parameter Linear Regression (MLR. The impact of increasing oceanic anthropogenic CO2 on the calcium carbonate system in the ocean is reviewed briefly as well. Extensive studies of CaCO3 dissolution as a result of increasing anthropogenic CO2 in the ocean have revealed several distinct oceanic regions where the CaCO3 undersaturation zone has expanded.

  7. Monitoring CO2 in shock states.

    Science.gov (United States)

    Danin, Pierre-Eric; Siegenthaler, Nils; Levraut, Jacques; Bernardin, Gilles; Dellamonica, Jean; Bendjelid, Karim

    2015-10-01

    The primary end point when treating acute shock is to restore blood circulation, mainly by reaching macrocirculatory parameters. However, even if global haemodynamic goals can be achieved, microcirculatory perfusion may remain impaired, leading to cellular hypoxia and organ damage. Interestingly, few methods are currently available to measure the adequacy of organ blood flow and tissue oxygenation. The rise in tissue partial pressure of carbon dioxide (CO2) has been observed when tissue perfusion is decreased. In this regard, tissue partial pressure of CO2 has been proposed as an early and reliable marker of tissue hypoxia even if the mechanisms of tissue partial pressure in CO2 rise during hypoperfusion remain unclear. Several technologies allow the estimation of CO2 content from different body sites: vascular, tissular (in hollow organs, mucosal or cutaneous), and airway. These tools remain poorly evaluated, and some are used but are not widely used in clinical practice. The present review clarifies the physiology of increasing tissue CO2 during hypoperfusion and underlines the specificities of the different technologies that allow bedside estimation of tissue CO2 content.

  8. Advanced CO2 Removal and Reduction System

    Science.gov (United States)

    Alptekin, Gokhan; Dubovik, Margarita; Copeland, Robert J.

    2011-01-01

    An advanced system for removing CO2 and H2O from cabin air, reducing the CO2, and returning the resulting O2 to the air is less massive than is a prior system that includes two assemblies . one for removal and one for reduction. Also, in this system, unlike in the prior system, there is no need to compress and temporarily store CO2. In this present system, removal and reduction take place within a single assembly, wherein removal is effected by use of an alkali sorbent and reduction is effected using a supply of H2 and Ru catalyst, by means of the Sabatier reaction, which is CO2 + 4H2 CH4 + O2. The assembly contains two fixed-bed reactors operating in alternation: At first, air is blown through the first bed, which absorbs CO2 and H2O. Once the first bed is saturated with CO2 and H2O, the flow of air is diverted through the second bed and the first bed is regenerated by supplying it with H2 for the Sabatier reaction. Initially, the H2 is heated to provide heat for the regeneration reaction, which is endothermic. In the later stages of regeneration, the Sabatier reaction, which is exothermic, supplies the heat for regeneration.

  9. CO2 Emission Factors for Coals

    Directory of Open Access Journals (Sweden)

    P. Orlović-Leko

    2015-03-01

    Full Text Available Emission factors are used in greenhouse gas inventories to estimate emissions from coal combustion. In the absence of direct measures, emissions factors are frequently used as a quick, low cost way to estimate emissions values. Coal combustion has been a major contributor to the CO2 flux into the atmosphere. Nearly all of the fuel carbon (99 % in coal is converted to CO2 during the combustion process. The carbon content is the most important coal parameter which is the measure of the degree of coalification (coal rank. Coalification is the alteration of vegetation to form peat, succeeded by the transformation of peat through lignite, sub-bituminous, bituminous to anthracite coal. During the geochemical or metamorphic stage, the progressive changes that occur within the coal are an increase in the carbon content and a decrease in the hydrogen and oxygen content resulting in a loss of volatiles. Heterogeneous composition of coal causes variation in CO2 emission from different coals. The IPCC (Intergovernmental Panel on Climate Change has produced guidelines on how to produce emission inventories which includes emission factors. Although 2006 IPCC Guidelines provided the default values specified according to the rank of the coal, the application of country-specific emission factors was recommended when estimating the national greenhouse gas emissions. This paper discusses the differences between country-specific emission factors and default IPCC CO2 emission factors, EF(CO2, for coals. Also, this study estimated EF(CO2 for two different types of coals and peat from B&H, on the basis fuel analyses. Carbon emission factors for coal mainly depend on the carbon content of the fuel and vary with both rank and geographic origin, which supports the idea of provincial variation of carbon emission factors. Also, various other factors, such as content of sulphur, minerals and macerals play an important role and influence EF(CO2 from coal. Carbonate minerals

  10. Miscibility evolution of polycarbonate/polystyrene blends during compounding

    DEFF Research Database (Denmark)

    Chuai, Chengzhi; Almdal, Kristoffer; Johannsen, Ib

    2002-01-01

    The miscibility evolution of polycarbonate/polystyrene (PC/PS) blends during the compounding process in three blending methods of industrial relevance, namely melt blending, remelt blending in a twin-screw extruder and third melt blending in an injection molding machine, was investigated by measu......The miscibility evolution of polycarbonate/polystyrene (PC/PS) blends during the compounding process in three blending methods of industrial relevance, namely melt blending, remelt blending in a twin-screw extruder and third melt blending in an injection molding machine, was investigated...

  11. CO2-Water-Rock Wettability: Variability, Influencing Factors, and Implications for CO2Geostorage.

    Science.gov (United States)

    Iglauer, Stefan

    2017-05-16

    Carbon geosequestration (CGS) has been identified as a key technology to reduce anthropogenic greenhouse gas emissions and thus significantly mitigate climate change. In CGS, CO 2 is captured from large point-source emitters (e.g., coal fired power stations), purified, and injected deep underground into geological formations for disposal. However, the CO 2 has a lower density than the resident formation brine and thus migrates upward due to buoyancy forces. To prevent the CO 2 from leaking back to the surface, four trapping mechanisms are used: (1) structural trapping (where a tight caprock acts as a seal barrier through which the CO 2 cannot percolate), (2) residual trapping (where the CO 2 plume is split into many micrometer-sized bubbles, which are immobilized by capillary forces in the pore network of the rock), (3) dissolution trapping (where CO 2 dissolves in the formation brine and sinks deep into the reservoir due to a slight increase in brine density), and (4) mineral trapping (where the CO 2 introduced into the subsurface chemically reacts with the formation brine or reservoir rock or both to form solid precipitates). The efficiency of these trapping mechanisms and the movement of CO 2 through the rock are strongly influenced by the CO 2 -brine-rock wettability (mainly due to the small capillary-like pores in the rock which form a complex network), and it is thus of key importance to rigorously understand CO 2 -wettability. In this context, a substantial number of experiments have been conducted from which several conclusions can be drawn: of prime importance is the rock surface chemistry, and hydrophilic surfaces are water-wet while hydrophobic surfaces are CO 2 -wet. Note that CO 2 -wet surfaces dramatically reduce CO 2 storage capacities. Furthermore, increasing pressure, salinity, or dissolved ion valency increases CO 2 -wettability, while the effect of temperature is not well understood. Indeed theoretical understanding of CO 2 -wettability and the

  12. Carbon Dioxide Clusters: (CO_2)_6 to (CO_2)13

    Science.gov (United States)

    McKellar, A. R. W.; Oliaee, J. Norooz; Dehghany, M.; Moazzen-Ahmadi, N.

    2011-06-01

    We recenty reported assignments of specific infrared bands in the CO_2 νb{3} region (˜2350 wn) to (CO_2)_6, (CO_2)_7, (CO_2)_9, (CO_2)10, (CO_2)11, (CO_2)12, and (CO_2)13. Spectra are obtained by direct absorption using a rapid-scan tuneable diode laser spectrometer to probe a pulsed supersonic slit-jet expansion and assignments are facilitated by recent calculations of Takeuchi based on the Murthy potential. (CO_2)_6 is a symmetric top with S_6 point group symmetry which can be thought of as a stack of two planar cyclic trimers. (CO_2)13 is also an S_6 symmetric top, and consists of a single CO_2 monomer surrounded by an slightly distorted icosahedral cage. The remaining clusters are asymmetric tops without symmetry. Here we report additional CO_2 cluster results. Calculations based on the SAPT-s potential indicate that the structure of (CO_2)10 may be slightly different from that given by Takeuchi/Murthy. An additional band is observed for each of (CO_2)13 and (CO_2)10. A feature observed at 2378.2 wn is assigned as a (CO_2)_6 parallel combination band involving the sum of a fundamental and a low-lying intermolecular vibration. Most significantly, two bands are assigned to a second isomer of (CO_2)_6. This is also a symmetric top, but now with S_4 symmetry. The two symmetric hexamer isomers observed spectroscopically correspond well with the lowest energy structures given by both the SAPT-s and Murthy intermolecular potentials. [1] J. Norooz Oliaee, M. Dehgany, N. Moazzen-Ahmadi, and A.R.W. McKellar, Phys. Chem. Chem. Phys. 13, 1297 (2011). [2] H. Takeuchi, J. Phys. Chem. A 107, 5703 (2008); C.S. Murthy, S.F. O'Shea, and I.R. McDonald, Mol. Phys. 50, 531 (1983). [3] R. Bukowski, J. Sadlej, B. Jeziorski, P. Jankowski, K. Szalewicz, S.A. Kucharski, H.L. Williams, and B.M. Rice, J. Chem. Phys. 110, 3785 (1999)

  13. Direct CO2-Methanation of flue gas

    Science.gov (United States)

    Müller, Klaus; Fleige, Michael; Rachow, Fabian; Israel, Johannes; Schmeißer, Dieter

    2013-04-01

    Already discovered by Paul Sabatier in 1902 the Hydrogenation according to CO2 + 4H2 ->CH4 + 2H2O nowadays is discussed in the course of the "Power-to-Gas" approach to utilize excess energy from renewable electricity generation in times of oversupply of electricity. We investigate the behavior of this process in a simulated flue gas atmosphere of conventional base load power plants, which could be used as constant sources of the reactant CO2. In relation to an approach related to carbon capture and cycling, the conversion of CO2 directly from the flue gas of a conventional power plant is a new aspect and has several advantages: The conversion of CO2 into methane could be integrated directly into the combustion process. Even older power plants could be upgraded and used as a possible source for CO2, in the same sense as the amine cleaning of flue gas, as a post combustion process. Further, waste heat of the power plant could be used as process energy for the catalytic reaction. Therefore the influence of different flue gas compositions such as varying contents of nitrogen and residual oxygen are tested in a laboratory scale. The heterogeneous catalysis process is investigated with regard to conversion rates, yield and selectivity and long-term stability of the Ni-catalyst. Also the influence of typical contaminations like SO2 is investigated and will be presented.

  14. CO2 and CO simulations and their source signature indicated by CO/CO2

    Science.gov (United States)

    Kawa, S. R.; Bian, H.

    2004-12-01

    Three years (2000-2002) atmospheric CO2 and CO fields are simulated by a Chemistry Transport Model driven by the assimilated meteorological fields from GEOS_4. The simulated CO2 and CO are evaluated by measurements from surface (CMDL), satellite (MOPITT/CO), and aircraft. The model-observation comparisons indicate reasonable agreement in both source and remote regions, and in the lower and upper troposphere. The simulation also captures the seasonality of CO2 and CO variations. The ratios of CO/CO2 are analyzed over different representative regions to identify the source signature, since the anthropogenic CO comes from the same combustion processes as CO2. This work enables us to improve satellite inversion estimates of CO2 sources and sinks by simultaneously using satellite CO measurement.

  15. CO2 sensing and CO2 regulation of stomatal conductance: advances and open questions

    Science.gov (United States)

    Engineer, Cawas; Hashimoto-Sugimoto, Mimi; Negi, Juntaro; Israelsson-Nordstrom, Maria; Azoulay-Shemer, Tamar; Rappel, Wouter-Jan; Iba, Koh; Schroeder, Julian

    2015-01-01

    Guard cells form epidermal stomatal gas exchange valves in plants and regulate the aperture of stomatal pores in response to changes in the carbon dioxide (CO2) concentration in leaves. Moreover, the development of stomata is repressed by elevated CO2 in diverse plant species. Evidence suggests that plants can sense CO2 concentration changes via guard cells and via mesophyll tissues in mediating stomatal movements. We review new discoveries and open questions on mechanisms mediating CO2-regulated stomatal movements and CO2 modulation of stomatal development, which together function in CO2-regulation of stomatal conductance and gas exchange in plants. Research in this area is timely in light of the necessity of selecting and developing crop cultivars which perform better in a shifting climate. PMID:26482956

  16. CO2-Switchable Membranes Prepared by Immobilization of CO2-Breathing Microgels.

    Science.gov (United States)

    Zhang, Qi; Wang, Zhenwu; Lei, Lei; Tang, Jun; Wang, Jianli; Zhu, Shiping

    2017-12-20

    Herein, we report the development of a novel CO 2 -responsive membrane system through immobilization of CO 2 -responsive microgels into commercially available microfiltration membranes using a method of dynamic adsorption. The microgels, prepared from soap-free emulsion polymerization of CO 2 -responsive monomer 2-(diethylamino)ethyl methacrylate (DEA), can be reversibly expanded and shrunken upon CO 2 /N 2 alternation. When incorporated into the membranes, this switching behavior was preserved and further led to transformation between microfiltration and ultrafiltration membranes, as indicated from the dramatic changes on water flux and BSA rejection results. This CO 2 -regulated performance switching of membranes was caused by the changes of water transportation channel, as revealed from the dynamic water contact angle tests and SEM observation. This work represents a simple yet versatile strategy for making CO 2 -responsive membranes.

  17. CO2 and CO Simulations and Their Source Signature Indicated by CO/CO2

    Science.gov (United States)

    Kawa, Randy; Huisheng, Bian

    2004-01-01

    Three years (2000-2002) atmospheric CO2 and CO fields are simulated by a Chemistry Transport Model driven by the assimilated meteorological fields from GEOS-4. The simulated CO2 and CO are evaluated by measurements from surface (CMDL), satellite (MOPITT/CO), and aircraft. The model-observation comparisons indicate reasonable agreement in both source and remote regions, and in the lower and upper troposphere. The simulation also captures the seasonality of CO2 and CO variations. The ratios of CO/CO2 are analyzed over different representative regions to identify the source signature, since the anthropogenic CO comes fiom the same combustion processes as CO2. This work enables us to improve satellite inversion estimates of CO2 sources and sinks by simultaneously using satellite CO measurement.

  18. Metal-CO2 Batteries on the Road: CO2 from Contamination Gas to Energy Source.

    Science.gov (United States)

    Xie, Zhaojun; Zhang, Xin; Zhang, Zhang; Zhou, Zhen

    2017-04-01

    Rechargeable nonaqueous metal-air batteries attract much attention for their high theoretical energy density, especially in the last decade. However, most reported metal-air batteries are actually operated in a pure O2 atmosphere, while CO2 and moisture in ambient air can significantly impact the electrochemical performance of metal-O2 batteries. In the study of CO2 contamination on metal-O2 batteries, it has been gradually found that CO2 can be utilized as the reactant gas alone; namely, metal-CO2 batteries can work. On the other hand, investigations on CO2 fixation are in focus due to the potential threat of CO2 on global climate change, especially for its steadily increasing concentration in the atmosphere. The exploitation of CO2 in energy storage systems represents an alternative approach towards clean recycling and utilization of CO2 . Here, the aim is to provide a timely summary of recent achievements in metal-CO2 batteries, and inspire new ideas for new energy storage systems. Moreover, critical issues associated with reaction mechanisms and potential directions for future studies are discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Measuring Nitrous Oxide Mass Transfer into Non-Aqueous CO2BOL CO2 Capture Solvents

    Energy Technology Data Exchange (ETDEWEB)

    Whyatt, Greg A.; Freeman, Charles J.; Zwoster, Andy; Heldebrant, David J.

    2016-03-28

    This paper investigates CO2 absorption behavior in CO2BOL solvents by decoupling the physical and chemical effects using N2O as a non-reactive mimic. Absorption measurements were performed using a wetted-wall contactor. Testing was performed using a “first generation” CO2 binding organic liquid (CO2BOL), comprised of an independent base and alcohol. Measurements were made with N2O at a lean (0.06 mol CO2/mol BOL) and rich (0.26 mol CO2/mol BOL) loading, each at three temperatures (35, 45 and 55 °C). Liquid-film mass transfer coefficients (kg') were calculated by subtracting the gas film resistance – determined from a correlation from literature – from the overall mass transfer measurement. The resulting kg' values for N2O in CO2BOLs were found to be higher than that of 5 M aqueous MEA under comparable conditions, which is supported by published measurements of Henry’s coefficients for N2O in various solvents. These results suggest that the physical solubility contribution for CO2 absorption in CO2BOLs is greater than that of aqueous amines, an effect that may pertain to other non-aqueous solvents.

  20. THE HIGH GAIN CO2 LASER BY EFFECTIVE MIXING OF N2 AND CO2 GAS

    OpenAIRE

    Hara, H.; Fujisawa, A.

    1980-01-01

    A high-gain CO2 laser is described in which vibrationally excited N2 gas and cold CO2 gas are mixed effectively by means of the diffusion of CO2 gas into N2 gas. By using different types of mixing techniques, a maximum gain of 11 m-1 was obtained when CO2 gas was injected parallel to the expanding N2 gas flow. An output power of 4 W was obtained from an 1.2 cm active length. In addition, He gas addition to the N2 gas flow was found to decrease the small-signal gain with increasing He gas flow...

  1. Investigation into Optimal CO2 Concentration for CO2 Capture from Aluminium Production

    OpenAIRE

    Mathisen, Anette; Sørensen, Henriette; Melaaen, Morten; Müller, Gunn-Iren

    2013-01-01

    Capture of CO2 from aluminum production has been simulated using Aspen Plus and Aspen Hysys. The technology used for aluminum production is the Hall-Héroult and the current cell design necessitates that large amounts of false air is supplied to the cells. This results in a CO2 concentration in the process gas at around 1 vol%, which is considered uneconomical for CO2 capture. Therefore, the aim of this investigation is to evaluate the CO2 capture from aluminum production when the process gas ...

  2. The Abundance of Atmospheric CO2 in Ocean Exoplanets: a Novel CO2 Deposition Mechanism

    Science.gov (United States)

    Levi, A.; Sasselov, D.; Podolak, M.

    2017-03-01

    We consider super-Earth sized planets which have a water mass fraction large enough to form an external mantle composed of high-pressure water-ice polymorphs and also lack a substantial H/He atmosphere. We consider such planets in their habitable zone, so that their outermost condensed mantle is a global, deep, liquid ocean. For these ocean planets, we investigate potential internal reservoirs of CO2, the amount of CO2 dissolved in the ocean for the various saturation conditions encountered, and the ocean-atmosphere exchange flux of CO2. We find that, in a steady state, the abundance of CO2 in the atmosphere has two possible states. When wind-driven circulation is the dominant CO2 exchange mechanism, an atmosphere of tens of bars of CO2 results, where the exact value depends on the subtropical ocean surface temperature and the deep ocean temperature. When sea-ice formation, acting on these planets as a CO2 deposition mechanism, is the dominant exchange mechanism, an atmosphere of a few bars of CO2 is established. The exact value depends on the subpolar surface temperature. Our results suggest the possibility of a negative feedback mechanism, unique to water planets, where a reduction in the subpolar temperature drives more CO2 into the atmosphere to increase the greenhouse effect.

  3. Decoupling of CO2 emissions and GDP

    Directory of Open Access Journals (Sweden)

    Yves Rocha de Salles Lima

    2016-12-01

    Full Text Available The objetive of this work is to analyze the variation of CO2 emissions and GDP per capita throughout the years and identify the possible interaction between them. For this purpose, data from the International Energy Agency was collected on two countries, Brazil and the one with the highest GDP worldwide, the United States. Thus, the results showed that CO2 emissions have been following the country’s economic growth for many years. However, these two indicators have started to decouple in the US in 2007 while in Brazil the same happened in 2011. Furthermore, projections for CO2 emissions are made until 2040, considering 6 probable scenarios. These projections showed that even if the oil price decreases, the emissions will not be significantly affected as long as the economic growth does not decelerate.

  4. Chilled Ammonia Process for CO2 Capture

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Thomsen, Kaj; Well, Willy J.M. van

    2010-01-01

    The chilled ammonia process absorbs the CO2 at low temperature (2–10°C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows good...... perspectives for decreasing the heat requirement. However, a scientific understanding of the processes is required. The thermodynamic properties of the NH3–CO2–H2O system were described using the extended UNIQUAC electrolyte model developed by Thomsen and Rasmussen in a temperature range from 0 to 110°C...... and pressure up to 100bars. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The heat requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that a heat requirement for the desorber lower than 2GJ/ton CO2...

  5. The ATLAS IBL CO2 Cooling System

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00237783; The ATLAS collaboration; Zwalinski, L.; Bortolin, C.; Vogt, S.; Godlewski, J.; Crespo-Lopez, O.; Van Overbeek, M.; Blaszcyk, T.

    2017-01-01

    The ATLAS Pixel detector has been equipped with an extra B-layer in the space obtained by a reduced beam pipe. This new pixel detector called the ATLAS Insertable B-Layer (IBL) is installed in 2014 and is operational in the current ATLAS data taking. The IBL detector is cooled with evaporative CO2 and is the first of its kind in ATLAS. The ATLAS IBL CO2 cooling system is designed for lower temperature operation (<-35⁰C) than the previous developed CO2 cooling systems in High Energy Physics experiments. The cold temperatures are required to protect the pixel sensors for the high expected radiation dose up to 550 fb^-1 integrated luminosity.

  6. CW CO2 Laser Induced Chemical Reactions

    Science.gov (United States)

    Pola, Joseph

    1989-05-01

    CW CO2 laser driven reactions between sulfur hexafluoride and carbon oxide, carbon suboxide, carbonyl sulfide and carbon disulfide proceed at subatmospheric pressures and yield fluorinated carbon compounds and sulfur tetrafluoride. CW CO2 laser driven reactions of organic compounds in the presence of energy-conveying sulfur hexafluoride show reaction course different from that normally observed due to elimination of reactor hot surface effects. The examples concern the decomposition of polychlorohydrocarbons, 2-nitropropane, tert.-butylamine, allyl chloride, spirohexane, isobornyl acetate and the oxidation of haloolefins. CW CO2 laser induced fragmentation of 1-methyl-l-silacyclobutanes and 4-silaspiro(3.4)octane in the presence of sulfur hexafluoride is an effective way for preparation and deposition of stable organosilicon polymers.

  7. CO2 utilization: Developments in conversion processes

    Directory of Open Access Journals (Sweden)

    Erdogan Alper

    2017-03-01

    The potential utilization of CO2, captured at power plants, should also been taken into consideration for sustainability. This CO2 source, which is potentially a raw material for the chemical industry, will be available at sufficient quality and at gigantic quantity upon realization of on-going tangible capture projects. Products resulting from carboxylation reactions are obvious conversions. In addition, provided that enough supply of energy from non-fossil resources, such as solar [1], is ensured, CO2 reduction reactions can produce several valuable commodity chemicals including multi-carbon compounds, such as ethylene and acrylic acid, in addition to C1 chemicals and polymers. Presently, there are only few developing technologies which can find industrial applications. Therefore, there is a need for concerted research in order to assess the viability of these promising exploratory technologies rationally.

  8. The Idea of Global CO2 Trade

    DEFF Research Database (Denmark)

    Svendsen, Gert Tinggaard

    1999-01-01

    The US has been criticized for wanting to earn a fortune on a global CO2 market. However, compared to the situation without trade and provided that such a market is designed so that it does not pay to cheat, a global CO2 market may provide the world with an epoch-making means of cost......-effective control which can solve future global environmental problems. The economic gains from 'hot air' distributions of permits and CO2 trade make the system politically attractive to potential participants. For example, vital financial subsidies from the EU to Eastern Europe are to be expected. It will probably...... not pay to cheat if quotas are renewed periodically by the UN. Cheating countries are then to be excluded from further profitable trade. Also, a periodical renewal of permits makes it possible to tighten target levels in the future....

  9. The Idea of Global CO2 Trade

    DEFF Research Database (Denmark)

    Svendsen, Gert Tinggaard

    1998-01-01

    The US has been criticized for wanting to earn a fortune on a global CO2 market. However, compared to the situation without trade and provided that such a market is designed so that it does not pay to cheat, a global CO2 market may provide the world with an epoch-making means of cost......-effective control which can solve future global environmental problems. The gains from CO2 trade may give vital financial subsidies from the EU to Eastern Europe, for example, and it will probably not pay to cheat if quotas are renewed periodically by the UN. Cheating countries are then to be excluded from further...... profitable trade. Also, a periodical renewal of permits makes it possible to tighten target levels in the future....

  10. Membraneless water filtration using CO2

    Science.gov (United States)

    Shin, Sangwoo; Shardt, Orest; Warren, Patrick B.; Stone, Howard A.

    2017-05-01

    Water purification technologies such as microfiltration/ultrafiltration and reverse osmosis utilize porous membranes to remove suspended particles and solutes. These membranes, however, cause many drawbacks such as a high pumping cost and a need for periodic replacement due to fouling. Here we show an alternative membraneless method for separating suspended particles by exposing the colloidal suspension to CO2. Dissolution of CO2 into the suspension creates solute gradients that drive phoretic motion of particles. Due to the large diffusion potential generated by the dissociation of carbonic acid, colloidal particles move either away from or towards the gas-liquid interface depending on their surface charge. Using the directed motion of particles induced by exposure to CO2, we demonstrate a scalable, continuous flow, membraneless particle filtration process that exhibits low energy consumption, three orders of magnitude lower than conventional microfiltration/ultrafiltration processes, and is essentially free from fouling.

  11. Cutting weeds with a CO2 laser

    DEFF Research Database (Denmark)

    Heisel, T.; Schou, Jørgen; Christensen, S.

    2001-01-01

    Stems of Chenopodium album. and Sinapis arvensis. and leaves of Lolium perenne. were cut with a CO2 laser or with a pair of scissors. Treatments were carried out on greenhouse-grown pot plants at three different growth stages and at two heights. Plant dry matter was measured 2 to 5 weeks after...... treatment. The relationship between dry weight and laser energy was analysed using a non-linear dose-response regression model. The regression parameters differed significantly between the weed species. At all growth stages and heights S. arvensis was more difficult to cut with a CO2 laser than C. album....... When stems were cut below the meristems, 0.9 and 2.3 J mm(-1) of CO2 laser energy dose was sufficient to reduce by 90% the biomass of C. album and S. arvensis respectively. Regrowth appeared when dicotyledonous plant stems were cut above meristems, indicating that it is important to cut close...

  12. Equilibrium Solubility of CO2 in Alkanolamines

    DEFF Research Database (Denmark)

    Waseem Arshad, Muhammad; Fosbøl, Philip Loldrup; von Solms, Nicolas

    2014-01-01

    Equilibrium solubility of CO2 were measured in aqueous solutions of Monoethanolamine (MEA) and N,N-diethylethanolamine(DEEA). Equilibrium cells are generally used for these measurements. In this study, the equilibrium data were measured from the calorimetry. For this purpose a reaction calorimeter...... (model CPA 122 from ChemiSens AB, Sweden) was used. The advantage of this method is being the measurement of both heats of absorption and equilibrium solubility data of CO2 at the same time. The measurements were performed for 30 mass % MEA and 5M DEEA solutions as a function of CO2 loading at three...... different temperatures 40, 80 and 120 ºC. The measured 30 mass % MEA and 5M DEEA data were compared with the literature data obtained from different equilibrium cells which validated the use of calorimeters for equilibrium solubility measurements....

  13. Oxygen isotope fractionation in stratospheric CO2

    Science.gov (United States)

    Thiemens, M. H.; Jackson, T.; Mauersberger, K.; Schueler, B.; Morton, J.

    1991-01-01

    A new cryogenic collection system has been flown on board a balloon gondola to obtain separate samples of ozone and carbon dioxide without entrapping major atmospheric gases. Precision laboratory isotopic analysis of CO2 samples collected between 26 and 35.5 km show a mass-independent enrichment in both O-17 and O-18 of about 11 per mil above tropospheric values. Ozone enrichment in its heavy isotopes was 9 to 16 percent in O3-50 and 8 to 11 percent in O3-49, respectively (Schueler et al., 1990). A mechanism to explain the isotope enrichment in CO2 has been recently proposed by Yung et al. (1991). The model is based on the isotope exchange between CO2 and O3 via O(1D), resulting in a transfer of the ozone isotope enrichment to carbon dioxide. Predicted enrichment and measured values agree well.

  14. Kronikken: Handel og handling med CO2

    DEFF Research Database (Denmark)

    Andersen, M. S.

    2000-01-01

    De fleksible mekanismer i Kyoto-aftalen fortjener indgående overvejelser, ikke kun fordi de giver mulighed for en rabat på CO2-reduktionen, men også fordi de rummer globale og sikkerhedspolitiske dimensioner som er essentielle.......De fleksible mekanismer i Kyoto-aftalen fortjener indgående overvejelser, ikke kun fordi de giver mulighed for en rabat på CO2-reduktionen, men også fordi de rummer globale og sikkerhedspolitiske dimensioner som er essentielle....

  15. Do Tree Stems Recapture Respired CO2?

    Science.gov (United States)

    Hilman, B.; Angert, A.

    2016-12-01

    Tree stem respiration is an important, yet not well understood, component of the terrestrial carbon cycle. Predicting how trees as whole organisms respond to changes in climate and atmospheric CO2 requires understanding of the variability in the fraction of assimilated carbon allocated to respiration, versus the allocation to growth, damage repair, and to rhizosphere symbionts. Here we used the ratio of CO2 efflux/O2 influx (Apparent Respiratory Quotient, ARQ) to study stem respiration. The ARQ in trees stems is predicted to be 1.0, as a result of carbohydrates metabolism. Lower than 1.0 ARQ values may indicate a local assimilation of respired CO2, or dissolution and transport of CO2 in the xylem stream. We measured stems ARQ in 16 tree species at tropical, Mediterranean and temperate ecosystems using stem chambers and in-vitro incubations. The CO2 and O2 were measured by a system we developed, which is based on an IRGA and a Fuel-cell O2 analyzer (Hilman and Angert 2016). We found typical values of ARQ in the range of 0.4-0.8. Since incubations of detach stem tissues yielded similar ARQ values, and since the influence of natural variations in the transpiration stream on ARQ was found to be small, we conclude that the removal of the respired CO2 is not via dissolution in the xylem stream. Using 13C labeling, dark fixation of stem tissues was detected, which is most probably phosphoenolpyruvate carboxylase (PEPC) mediated. Hence, we suggest that in-stem dark fixation of respired CO2 to organic acids (e.g. malate) affects the outgoing efflux. Further research should determine if these organic acids are transported to the canopy, stored in the stem, or transported to the roots to serve as exudates. Hilman B, Angert A (2016) Measuring the ratio of CO2 efflux to O2 influx in tree stem respiration. Tree Physiol 2016, doi: 10.1093/treephys/tpw057

  16. 10 MW Supercritical CO2 Turbine Test

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, Craig

    2014-01-29

    The Supercritical CO2 Turbine Test project was to demonstrate the inherent efficiencies of a supercritical carbon dioxide (s-CO2) power turbine and associated turbomachinery under conditions and at a scale relevant to commercial concentrating solar power (CSP) projects, thereby accelerating the commercial deployment of this new power generation technology. The project involved eight partnering organizations: NREL, Sandia National Laboratories, Echogen Power Systems, Abengoa Solar, University of Wisconsin at Madison, Electric Power Research Institute, Barber-Nichols, and the CSP Program of the U.S. Department of Energy. The multi-year project planned to design, fabricate, and validate an s-CO2 power turbine of nominally 10 MWe that is capable of operation at up to 700°C and operates in a dry-cooled test loop. The project plan consisted of three phases: (1) system design and modeling, (2) fabrication, and (3) testing. The major accomplishments of Phase 1 included: Design of a multistage, axial-flow, s-CO2 power turbine; Design modifications to an existing turbocompressor to provide s-CO2 flow for the test system; Updated equipment and installation costs for the turbomachinery and associated support infrastructure; Development of simulation tools for the test loop itself and for more efficient cycle designs that are of greater commercial interest; Simulation of s-CO2 power cycle integration into molten-nitrate-salt CSP systems indicating a cost benefit of up to 8% in levelized cost of energy; Identification of recuperator cost as a key economic parameter; Corrosion data for multiple alloys at temperatures up to 650ºC in high-pressure CO2 and recommendations for materials-of-construction; and Revised test plan and preliminary operating conditions based on the ongoing tests of related equipment. Phase 1 established that the cost of the facility needed to test the power turbine at its full power and temperature would exceed the planned funding for Phases 2 and 3. Late

  17. Modelling the Martian CO2 Ice Clouds

    Science.gov (United States)

    Listowski, Constantino; Määttänen, A.; Montmessin, F.; Lefèvre, F.

    2012-10-01

    Martian CO2 ice cloud formation represents a rare phenomenon in the Solar System: the condensation of the main component of the atmosphere. Moreover, on Mars, condensation occurs in a rarefied atmosphere (large Knudsen numbers, Kn) that limits the growth efficiency. These clouds form in the polar winter troposphere and in the mesosphere near the equator. CO2 ice cloud modeling has turned out to be challenging: recent efforts (e.g. [1]) fail in explaining typical small sizes (80 nm-130 nm) observed for mesospheric clouds [2]. Supercold pockets (TWood, S. E., (1999), Ph.D. thesis, UCLA [6] Young, J. B., J. Geophys. Res., 36, 294-2956, 1993

  18. CO2 flux from Javanese mud volcanism

    OpenAIRE

    Quei?er, M.; Burton, M.; Arzilli, F.; Chiarugi, A.; Marliyani, G.I; Anggara, F.; Harijoko, A.

    2017-01-01

    Abstract Studying the quantity and origin of CO2 emitted by back?arc mud volcanoes is critical to correctly model fluid?dynamical, thermodynamical, and geochemical processes that drive their activity and to constrain their role in the global geochemical carbon cycle. We measured CO2 fluxes of the Bledug Kuwu mud volcano on the Kendeng Fold and thrust belt in the back arc of Central Java, Indonesia, using scanning remote sensing absorption spectroscopy. The data show that the expelled gas is r...

  19. Toxic emissions and devaluated CO2-neutrality

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    Environmental, energy and climate policies need fresh reflections. In order to evaluate toxics reduction policies the Stockholm Convention on Persistent Organic Pollutants is mandatory. Denmark's function as lead country for dioxin research in the context of the OSPAR Convention is contrasted...... with a climate policy whose goals of CO2-reduction were made operational by green-wash. Arguments are given for the devaluation of CO2- neutrality in case of burning wood. Alternative practices as storing C in high quality wood products and/or leaving wood in the forest are recommended. A counter...

  20. Leak Path Development in CO2 Wells

    Science.gov (United States)

    Torsater, M.; Todorovic, J.; Opedal, N.; Lavrov, A.

    2014-12-01

    Wells have in numerous scientific works been denoted the "weak link" of safe and cost-efficient CO2 Capture and Storage (CCS). Whether they are active or abandoned, all wells are man-made intrusions into the storage reservoir with sealing abilities depending on degradable materials like steel and cement. If dense CO2 is allowed to expand (e.g. due to leakage) it will cool down its surroundings and cause strong thermal and mechanical loading on the wellbore. In addition, CO2 reacts chemically with rock, cement and steel. To ensure long-term underground containment, it is therefore necessary to study how, why, where and when leakage occurs along CO2wells. If cement bonding to rock or casing is poor, leak paths can form already during drilling and completion of the well. In the present work, we have mapped the bonding quality of cement-rock and cement-steel interfaces - and measured their resistance towards CO2 flow. This involved a large experimental matrix including different rocks, steels, cement types and well fluids. The bonding qualities were measured on composite cores using micro computed tomography (µ-CT), and CO2 was flooded through the samples to determine leakage rates. These were further compared to numerical simulations of leakage through the digitalized µ-CT core data, and CO2chemical interactions with the materials were mapped using electron microscopy. We also present a new laboratory set-up for measuring how well integrity is affected by downhole temperature variations - and we showcase some initial results. Our work concludes that leak path development in CO2 wells depends critically on the drilling fluids and presflushes/spacers chosen already during drilling and completion of a well. Fluid films residing on rock and casing surfaces strongly degrade the quality of cement bonding. The operation of the well is also important, as even slight thermal cycling (between 10°C and 95°C on casing) leads to significant de-bonding of the annular cement.

  1. Differential miscibility properties of various phosphatidylcholine/lysophosphatidylcholine mixtures

    NARCIS (Netherlands)

    Echteld, C.J.A. van; Kruijff, B. de; Gier, J. de

    1980-01-01

    Using enthalphy data from differential scanning calorimetry experiments and 13C-NMR linewidths of specifically (N-Me-13C)-labelled lipids, the miscibility properties of phosphatidylcholines and lysophosphatidylcholines in liposomal dispersions have been investigated. It was found that 16 : 0

  2. Research note : Miscibility behaviour of binary mixtures of benzyl ...

    African Journals Online (AJOL)

    Miscibility of binary mixtures of benzyl benzoate and liquid paraffin as functions of temperature and composition has been determined using phase separation method. The binary mixtures demonstrated a critical (upper) solution temperature of 35 °C at 101325 Nm-2 with a mixing gap. A tie-line drawn at 28 °C across the ...

  3. Effective Algorithm for Calculation of Minimum Miscibility Pressure

    DEFF Research Database (Denmark)

    Jessen, Kristian; Michelsen, Michael Locht; Stenby, Erling Halfdan

    1998-01-01

    This paper describes a new algorithm developed for calculation of the minimum miscibility pressure (MMP) for the displacement of oil by a multicomponent injection gas. The algorithm is based on the key tie line identification approach initially studied by Wang and Orr . A new global formulation i...

  4. Sustained effects of atmospheric [CO2] and nitrogen availability on forest soil CO2 efflux

    Science.gov (United States)

    A. Christopher Oishi; Sari Palmroth; Kurt H. Johnsen; Heather R. McCarthy; Ram. Oren

    2014-01-01

    Soil CO2 efflux (Fsoil) is the largest source of carbon from forests and reflects primary productivity as well as how carbon is allocated within forest ecosystems. Through early stages of stand development, both elevated [CO2] and availability of soil nitrogen (N; sum of mineralization, deposition, and fixation) have been shown to increase gross primary productivity,...

  5. Uncertainties in the CO2 buget associated to boundary layer dynamics and CO2-advection

    NARCIS (Netherlands)

    Kaikkonen, J.P.; Pino, D.; Vilà-Guerau de Arellano, J.

    2012-01-01

    The relationship between boundary layer dynamics and carbon dioxide (CO2) budget in the convective boundary layer (CBL) is investigated by using mixed-layer theory. We derive a new set of analytical relations to quantify the uncertainties on the estimation of the bulk CO2 mixing ratio and the

  6. Heterotrophic fixation of CO2 in soil

    Czech Academy of Sciences Publication Activity Database

    Šantrůčková, Hana; Bird, M. I.; Elhottová, Dana; Novák, Jaroslav; Picek, T.; Šimek, Miloslav; Tykva, Richard

    2005-01-01

    Roč. 49, č. 2 (2005), s. 218-225 ISSN 0095-3628 R&D Projects: GA ČR(CZ) GA206/02/1036; GA AV ČR(CZ) IAA6066901 Institutional research plan: CEZ:AV0Z60660521 Keywords : heterotrophic fixation * CO2 * soil Subject RIV: EH - Ecology, Behaviour Impact factor: 2.674, year: 2005

  7. Carbon dioxide (CO2) utilizing strain database

    African Journals Online (AJOL)

    Jane

    2011-10-17

    Oct 17, 2011 ... Culling of excess carbon dioxide from our environment is one of the major challenges to scientific communities. Many physical, chemical and biological methods have been practiced to overcome this problem. The biological means of CO2 fixation using various microorganisms is gaining importance.

  8. 76 FR 15249 - Deferral for CO2

    Science.gov (United States)

    2011-03-21

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 51, 52, 70, and 71 RIN 2060-AQ79 Deferral for CO2 Emissions From Bioenergy and Other Biogenic Sources Under the Prevention of Significant Deterioration (PSD) and Title V Programs: Proposed...

  9. Artificial photosynthesis - CO2 towards methanol

    Science.gov (United States)

    Nazimek, D.; Czech, B.

    2011-03-01

    The new insight into the problem of carbon dioxide utilization into valuable compound - methanol and then its transformation into fuel is presented. Because the highly endothermic requirements of the reaction of CO2 hydrogenation a photocatalytic route is applied. Combining of the two reactions: water splitting and CO2 hydrogenation using H2O as a source of hydrogen at the same time and place are proposed. The studies over modified TiO2 catalysts supported on Al2O3 were conducted in a self-designed circulated photocatalytic reaction system under at room temperature and constant pressure. Experimental results indicated that the highest yield of the photoreduction of CO2 with H2O were obtained using TiO2 with the active anatase phase modified by Ru and WO3 addition. The conversion was very high - almost 97% of CO2 was transformed mainly into methanol (14%vol.) and into small amount of formic and acetic acid and ester.

  10. Iconic CO2 Time Series at Risk

    NARCIS (Netherlands)

    Houweling, S.; Badawy, B.; Basu, S.; Krol, M.C.; Röckmann, T.; Vermeulen, A.

    2012-01-01

    THE STEADY RISE IN ATMOSPHERIC LONGlived greenhouse gas concentrations is the main driver of contemporary climate change. The Mauna Loa CO2 time series (1, 2), started by C. D. Keeling in 1958 and maintained today by the Scripps Institution of Oceanography and the Earth System Research Laboratory

  11. Bosch CO2 Reduction System Development

    Science.gov (United States)

    Holmes, R. F.; King, C. D.; Keller, E. E.

    1976-01-01

    Development of a Bosch process CO2 reduction unit was continued, and, by means of hardware modifications, the performance was substantially improved. Benefits of the hardware upgrading were demonstrated by extensive unit operation and data acquisition in the laboratory. This work was accomplished on a cold seal configuration of the Bosch unit.

  12. Harvesting Energy from CO2 Emissions

    NARCIS (Netherlands)

    Hamelers, H.V.M.; Schaetzle, O.; Paz-García, J.M.; Biesheuvel, P.M.; Buisman, C.J.N.

    2014-01-01

    When two fluids with different compositions are mixed, mixing energy is released. This holds true for both liquids and gases, though in the case of gases, no technology is yet available to harvest this energy source. Mixing the CO2 in combustion gases with air represents a source of energy with a

  13. Extraction of lipids from microalgae using CO2-expanded methanol and liquid CO2.

    Science.gov (United States)

    Paudel, Ashok; Jessop, Michael J; Stubbins, Spencer H; Champagne, Pascale; Jessop, Philip G

    2015-05-01

    The use of CO2-expanded methanol (cxMeOH) and liquid carbon dioxide (lCO2) is proposed to extract lipids from Botryococcus braunii. When compressed CO2 dissolves in methanol, the solvent expands in volume, decreases in polarity and so increases in its selectivity for biodiesel desirable lipids. Solid phase extraction of the algal extract showed that the cxMeOH extracted 21 mg of biodiesel desirable lipids per mL of organic solvent compared to 3mg/mL using either neat methanol or chloroform/methanol mixture. The non-polar lCO2 showed a high affinity for non-polar lipids. Using lCO2, it is possible to extract up to 10% neutral lipids relative to the mass of dry algae. Unlike extractions using conventional solvents, these new methods require little to no volatile, flammable, or chlorinated organic solvents. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Flash scanning the CO2 laser: a revival of the CO2 laser in plastic surgery

    Science.gov (United States)

    Lach, Elliot

    1994-09-01

    The CO2 laser has broad clinical application yet also presents a number of practical disadvantages. These drawbacks have limited the success and utilization of this laser in plastic surgery. Flashscanner technology has recently been used for char-free CO2 laser surgery of the oropharynx, the external female genital tract, and perirectal mucosa. A commercially available optomechanical flashscanner unit `Swiftlase,' was adapted to a CO2 laser and used for treatment in numerous plastic surgical applications. Conditions and situations that were treated in this study included generalized neurofibromatosis, tuberous sclerosis, rhinophyma, viral warts, breast reconstruction, and deepithelialization prior to microsurgery or local flap transfer and/or skin graft placement. There were no significant wound healing complications. Some patients previously sustained undue scarring from conventional CO2 laser surgery. Conservative, primarily ablative CO2 laser surgery with the Swiftlase has usefulness for treatment of patients in plastic surgery including those that were previously unsuccessfully treated.

  15. The Li–CO2 battery: a novel method for CO2 capture and utilization

    KAUST Repository

    Xu, Shaomao

    2013-01-01

    We report a novel primary Li-CO2 battery that consumes pure CO2 gas as its cathode. The battery exhibits a high discharge capacity of around 2500 mA h g-1 at moderate temperatures. At 100 °C the discharge capacity is close to 1000% higher than that at 40 °C, and the temperature dependence is significantly weaker for higher surface area carbon cathodes. Ex-situ FTIR and XRD analyses convincingly show that lithium carbonate (Li2CO3) is the main component of the discharge product. The feasibility of similar primary metal-CO2 batteries based on earth abundant metal anodes, such as Al and Mg, is demonstrated. The metal-CO2 battery platform provides a novel approach for simultaneous capturing of CO2 emissions and producing electrical energy. © 2013 The Royal Society of Chemistry.

  16. Rapid CO2 permeation across biological membranes: implications for CO2 venting from tissue.

    Science.gov (United States)

    Hulikova, Alzbeta; Swietach, Pawel

    2014-07-01

    The degree to which cell membranes are barriers to CO2 transport remains controversial. Proteins, such as aquaporins and Rh complex, have been proposed to facilitate CO2 transport, implying that the nonchannel component of membranes must have greatly reduced CO2 permeability. To determine whether membrane CO2 permeation is rate limiting for gas transport, the spread of CO2 across multicellular tissue growths (spheroids) was measured using intracellular pH as a spatial readout. Colorectal HCT116 cells have basal water and NH3 permeability, indicating the functional absence of aquaporins and gas channels. However, CO2 diffusivity in HCT116 spheroids was only 24 ± 4% lower than in pure water, which can be accounted for fully by volume exclusion due to proteins. Diffusivity was unaffected by blockers of aquaporins and Rh complex (Hg(2+), p-chloromercuribenzoic acid, and 4,4'-diisothiocyano-2,2'-stilbene-disulfonic acid) but decreased under hypertonic conditions (by addition of 300 mOsm mannitol), which increases intracellular protein crowding. Similar CO2 diffusivity was measured in spheroids of T47D breast cells (basal water permeability) and NHDF-Ad fibroblasts (aquaporin-facilitated water permeability). In contrast, diffusivity of NH3, a smaller but less lipophilic gas, was considerably slower than in pure water, as expected from rate-limiting membrane permeation. In conclusion, membranes, even in the functional absence of proposed gas channels, do not restrict CO2 venting from tissue growths.-Hulikova, A., Swietach, P. Rapid CO2 permeation across biological membranes: implications for CO2 venting from tissue. © FASEB.

  17. Isolation of microorganisms from CO2 sequestration sites through enrichments under high pCO2

    Science.gov (United States)

    Peet, K. C.; Freedman, A. J.; Boreham, C.; Thompson, J. R.

    2012-12-01

    Carbon Capture and Storage (CCS) in geologic formations has the potential to reduce greenhouse gas emissions from fossil fuel processing and combustion. However, little is known about the effects that CO2 may have on biological activity in deep earth environments. To understand microorganisms associated with these environments, we have developed a simple high-pressure enrichment methodology to cultivate organisms capable of growth under supercritical CO2 (scCO2). Growth media targeting different subsurface functional metabolic groups is added to sterilized 316 stainless steel tubing sealed with quarter turn plug valves values and pressurized to 120-136 atm using a helium-padded CO2 tank, followed by incubation at 37 °C to achieve the scCO2 state. Repeated passages of crushed subsurface rock samples and growth media under supercritical CO2 headspaces are assessed for growth via microscopic enumeration. We have utilized this method to survey sandstone cores for microbes capable of growth under scCO2 from two different geologic sites targeted for carbon sequestration activities. Reproducible growth of microbial biomass under high pCO2 has been sustained from each site. Cell morphologies consist of primarily 1-2 μm rods and oval spores, with densities from 1E5-1E7 cells per ml of culture. We have purified and characterized a bacterial strain most closely related to Bacillus subterraneus (99% 16S rRNA identity) capable of growth under scCO2. Preliminary physiological characterization of this strain indicates it is a spore-forming facultative anaerobe able to grow in 0.5 to 50 ppt salinity. Genome sequencing and analysis currently in progress will help reveal genetic mechanisms of acclimation to high pCO2 conditions associated with geologic carbon sequestration.

  18. The Role of the CO2 Laser and Fractional CO2 Laser in Dermatology.

    Science.gov (United States)

    Omi, Tokuya; Numano, Kayoko

    2014-03-27

    Tremendous advances have been made in the medical application of the laser in the past few decades. Many diseases in the dermatological field are now indications for laser treatment that qualify for reimbursement by many national health insurance systems. Among laser types, the carbon dioxide (CO2) laser remains an important system for the dermatologist. The lasers used in photosurgery have wavelengths that differ according to their intended use and are of various types, but the CO2 laser is one of the most widely used lasers in the dermatology field. With its wavelength in the mid-infrared at 10,600 nm, CO2 laser energy is wellabsorbed in water. As skin contains a very high water percentage, this makes the CO2 laser ideal for precise, safe ablation with good hemostasis. In addition to its efficacy in ablating benign raised lesions, the CO2 laser has been reported to be effective in the field of esthetic dermatology in the revision of acne scars as well as in photorejuvenation. With the addition of fractionation of the beam of energy into myriad microbeams, the fractional CO2 laser has offered a bridge between the frankly full ablative indications and the nonablative skin rejuvenation systems of the 2000s in the rejuvenation of photoaged skin on and off the face. The CO2 laser remains an efficient, precise and safe system for the dermatologist. Technological advances in CO2 laser construction have meant smaller spot sizes and greater precision for laser surgery, and more flexibility in tip sizes and protocols for fractional CO2 laser treatment. The range of dermatological applications of the CO2 laser is expected to continue to increase in the future.

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

    Directory of Open Access Journals (Sweden)

    C. Lac

    2013-05-01

    Full Text Available Accurate simulation of the spatial and temporal variability of tracer mixing ratios over urban areas is a challenging and interesting task needed to be performed in order to utilise CO2 measurements in an atmospheric inverse framework and to better estimate regional CO2 fluxes. This study investigates the ability of a high-resolution model to simulate meteorological and CO2 fields around Paris agglomeration during the March field campaign of the CO2-MEGAPARIS project. The mesoscale atmospheric model Meso-NH, running at 2 km horizontal resolution, is coupled with the Town Energy Balance (TEB urban canopy scheme and with the Interactions between Soil, Biosphere and Atmosphere CO2-reactive (ISBA-A-gs surface scheme, allowing a full interaction of CO2 modelling between the surface and the atmosphere. Statistical scores show a good representation of the urban heat island (UHI with stronger urban–rural contrasts on temperature at night than during the day by up to 7 °C. Boundary layer heights (BLH have been evaluated on urban, suburban and rural sites during the campaign, and also on a suburban site over 1 yr. The diurnal cycles of the BLH are well captured, especially the onset time of the BLH increase and its growth rate in the morning, which are essential for tall tower CO2 observatories. The main discrepancy is a small negative bias over urban and suburban sites during nighttime (respectively 45 m and 5 m, leading to a few overestimations of nocturnal CO2 mixing ratios at suburban sites and a bias of +5 ppm. The diurnal CO2 cycle is generally well captured for all the sites. At the Eiffel tower, the observed spikes of CO2 maxima occur every morning exactly at the time at which the atmospheric boundary layer (ABL growth reaches the measurement height. At suburban ground stations, CO2 measurements exhibit maxima at the beginning and at the end of each night, when the ABL is fully contracted, with a strong spatio-temporal variability. A

  20. Root-derived CO2 efflux via xylem stream rivals soil CO2 efflux.

    Energy Technology Data Exchange (ETDEWEB)

    Aubrey, Doug, P.; Teskey, Robert, O.

    2009-07-01

    • Respiration consumes a large portion of annual gross primary productivity in forest ecosystems and is dominated by belowground metabolism. Here, we present evidence of a previously unaccounted for internal CO2 flux of large magnitude from tree roots through stems. If this pattern is shown to persist over time and in other forests, it suggests that belowground respiration has been grossly underestimated. • Using an experimental Populus deltoides plantation as a model system, we tested the hypothesis that a substantial portion of the CO2 released from belowground autotrophic respiration remains within tree root systems and is transported aboveground through the xylem stream rather than diffusing into the soil atmosphere. • On a daily basis, the amount of CO2 that moved upward from the root system into the stem via the xylem stream (0.26 mol CO2 m-2 d-1) rivalled that which diffused from the soil surface to the atmosphere (0.27 mol CO2 m-2 d-1). We estimated that twice the amount of CO2 derived from belowground autotrophic respiration entered the xylem stream as diffused into the soil environment. • Our observations indicate that belowground autotrophic respiration consumes substantially more carbohydrates than previously recognized and challenge the paradigm that all root-respired CO2 diffuses into the soil atmosphere.

  1. Global CO2 fluxes estimated from GOSAT retrievals of total column CO2

    Directory of Open Access Journals (Sweden)

    S. Basu

    2013-09-01

    Full Text Available We present one of the first estimates of the global distribution of CO2 surface fluxes using total column CO2 measurements retrieved by the SRON-KIT RemoTeC algorithm from the Greenhouse gases Observing SATellite (GOSAT. We derive optimized fluxes from June 2009 to December 2010. We estimate fluxes from surface CO2 measurements to use as baselines for comparing GOSAT data-derived fluxes. Assimilating only GOSAT data, we can reproduce the observed CO2 time series at surface and TCCON sites in the tropics and the northern extra-tropics. In contrast, in the southern extra-tropics GOSAT XCO2 leads to enhanced seasonal cycle amplitudes compared to independent measurements, and we identify it as the result of a land–sea bias in our GOSAT XCO2 retrievals. A bias correction in the form of a global offset between GOSAT land and sea pixels in a joint inversion of satellite and surface measurements of CO2 yields plausible global flux estimates which are more tightly constrained than in an inversion using surface CO2 data alone. We show that assimilating the bias-corrected GOSAT data on top of surface CO2 data (a reduces the estimated global land sink of CO2, and (b shifts the terrestrial net uptake of carbon from the tropics to the extra-tropics. It is concluded that while GOSAT total column CO2 provide useful constraints for source–sink inversions, small spatiotemporal biases – beyond what can be detected using current validation techniques – have serious consequences for optimized fluxes, even aggregated over continental scales.

  2. Effects of CO2 on stomatal conductance: do stomata open at very high CO2 concentrations?

    Science.gov (United States)

    Wheeler, R. M.; Mackowiak, C. L.; Yorio, N. C.; Sager, J. C.

    1999-01-01

    Potato and wheat plants were grown for 50 d at 400, 1000 and 10000 micromoles mol-1 carbon dioxide (CO2). and sweetpotato and soybean were grown at 1000 micromoles mol-1 CO2 in controlled environment chambers to study stomatal conductance and plant water use. Lighting was provided with fluorescent lamps as a 12 h photoperiod with 300 micromoles m-2 s-1 PAR. Mid-day stomatal conductances for potato were greatest at 400 and 10000 micromoles mol-1 and least at 1000 micromoles mol-1 CO2. Mid-day conductances for wheat were greatest at 400 micromoles mol-1 and least at 1000 and 10000 micromoles mol-1 CO2. Mid-dark period conductances for potato were significantly greater at 10000 micromoles mol-1 than at 400 or 1000 micromoles mol-1, whereas dark conductance for wheat was similar in all CO2 treatments. Temporarily changing the CO2 concentration from the native 1000 micromoles mol-1 to 400 micromoles mol-1 increased mid-day conductance for all species, while temporarily changing from 1000 to 10000 micromoles mol-1 also increased conductance for potato and sweetpotato. Temporarily changing the dark period CO2 from 1000 to 10000 micromoles mol-1 increased conductance for potato, soybean and sweetpotato. In all cases, the stomatal responses were reversible, i.e. conductances returned to original rates following temporary changes in CO2 concentration. Canopy water use for potato was greatest at 10000, intermediate at 400, and least at 1000 micromoles mol-1 CO2, whereas canopy water use for wheat was greatest at 400 and similar at 1000 and 10000 micromoles mol-1 CO2. Elevated CO2 treatments (i.e. 1000 and 10000 micromoles mol-1) resulted in increased plant biomass for both wheat and potato relative to 400 micromoles mol-1, and no injurious effects were apparent from the 10000 micromoles mol-1 treatment. Results indicate that super-elevated CO2 (i.e. 10000 micromoles mol-1) can increase stomatal conductance in some species, particularly during the dark period, resulting in

  3. Streamer parameters and breakdown in CO2

    Science.gov (United States)

    Seeger, M.; Avaheden, J.; Pancheshnyi, S.; Votteler, T.

    2017-01-01

    CO2 is a promising gas for the replacement of SF6 in high-voltage transmission and distribution networks due to its lower environmental impact. The insulation properties of CO2 are, therefore, of great interest. For this, the properties of streamers are important, since they determine the initial discharge propagation and possibly the transition to a leader. The present experimental investigation addresses the streamer inception and propagation at ambient temperature in the pressure range 0.05-0.5 MPa at both polarities. Streamer parameters, namely the stability field, radius and velocity, were deduced in uniform and in strongly non-uniform background fields. The measured breakdown fields can then be understood by streamer propagation and streamer-to-leader transition.

  4. CO2-DISSOLVED and Aqueous Gas Separation

    OpenAIRE

    Gorensek, Maximillian; Hamm, Luther; Blount, Gerald; Kervévan, Christophe; O'Neil, Kathleen

    2016-01-01

    International audience; CO2-DISSOLVED (Kervévan et al, 2014) is a multinational project funded by the French National Research Agency (ANR) with Phase II funded as one of the first Geodenergies projects. Geodenergies is a French industry-driven initiative grouping 18 companies and research organizations aiming at: (1) structuring a community of expertise to promote subsurface energy technologies that are key to a global energy transition; (2) cross-fertilizing to develop 3 emerging industrial...

  5. Aridity under conditions of increased CO2

    Science.gov (United States)

    Greve, Peter; Roderick, Micheal L.; Seneviratne, Sonia I.

    2016-04-01

    A string of recent of studies led to the wide-held assumption that aridity will increase under conditions of increasing atmospheric CO2 concentrations and associated global warming. Such results generally build upon analyses of changes in the 'aridity index' (the ratio of potential evaporation to precipitation) and can be described as a direct thermodynamic effect on atmospheric water demand due to increasing temperatures. However, there is widespread evidence that contradicts the 'warmer is more arid' interpretation, leading to the 'global aridity paradox' (Roderick et al. 2015, WRR). Here we provide a comprehensive assessment of modeled changes in a broad set of dryness metrics (primarily based on a range of measures of water availability) over a large range of realistic atmospheric CO2 concentrations. We use an ensemble of simulations from of state-of-the-art climate models to analyse both equilibrium climate experiments and transient historical simulations and future projections. Our results show that dryness is, under conditions of increasing atmospheric CO2 concentrations and related global warming, generally decreasing at global scales. At regional scales we do, however, identify areas that undergo changes towards drier conditions, located primarily in subtropical climate regions and the Amazon Basin. Nonetheless, the majority of regions, especially in tropical and mid- to northern high latitudes areas, display wetting conditions in a warming world. Our results contradict previous findings and highlight the need to comprehensively assess all aspects of changes in hydroclimatological conditions at the land surface. Roderick, M. L., P. Greve, and G. D. Farquhar (2015), On the assessment of aridity with changes in atmospheric CO2, Water Resour. Res., 51, 5450-5463

  6. Continuous CO2 extractor and methods

    Energy Technology Data Exchange (ETDEWEB)

    None listed

    2010-06-15

    The purpose of this CRADA was to assist in technology transfer from Russia to the US and assist in development of the technology improvements and applications for use in the U.S. and worldwide. Over the period of this work, ORNL has facilitated design, development and demonstration of a low-pressure liquid extractor and development of initial design for high-pressure supercritical CO2 fluid extractor.

  7. CO2 flux geothermometer for geothermal exploration

    Science.gov (United States)

    Harvey, M. C.; Rowland, J. V.; Chiodini, G.; Rissmann, C. F.; Bloomberg, S.; Fridriksson, T.; Oladottir, A. A.

    2017-09-01

    A new geothermometer (TCO2 Flux) is proposed based on soil diffuse CO2 flux and shallow temperature measurements made on areas of steam heated, thermally altered ground above active geothermal systems. This CO2 flux geothermometer is based on a previously reported CO2 geothermometer that was designed for use with fumarole analysis. The new geothermometer provides a valuable additional exploration tool for estimating subsurface temperatures in high-temperature geothermal systems. Mean TCO2 Flux estimates fall within the range of deep drill hole temperatures at Wairakei (New Zealand), Tauhara (New Zealand), Rotokawa (New Zealand), Ohaaki (New Zealand), Reykjanes (Iceland) and Copahue (Argentina). The spatial distribution of geothermometry estimates is consistent with the location of major upflow zones previously reported at the Wairakei and Rotokawa geothermal systems. TCO2 Flux was also evaluated at White Island (New Zealand) and Reporoa (New Zealand), where limited sub-surface data exists. Mode TCO2 Flux at White Island is high (320 °C), the highest of the systems considered in this study. However, the geothermometer relies on mineral-water equilibrium in neutral pH reservoir fluids, and would not be reliable in such an active and acidic environment. Mean TCO2 Flux at Reporoa (310 °C) is high, which indicates Reporoa has a separate upflow from the nearby Waiotapu geothermal system; an outflow from Waiotapu would not be expected to have such high temperature.

  8. CO2 cooling for HEP experiments

    CERN Document Server

    Verlaat; Van Lysebetten, A

    2008-01-01

    The new generation silicon detectors require more efficient cooling of the front-end electronics and the silicon sensors themselves. To minimize reverse annealing of the silicon sensors the cooling temperatures need to be reduced. Other important requirements of the new generation cooling systems are a reduced mass and a maintenance free operation of the hardware inside the detector. Evaporative CO2 cooling systems are ideal for this purpose as they need smaller tubes than conventional systems. The heat transfer capability of evaporative CO2 is high. CO2 is used as cooling fluid for the LHCb-VELO and the AMS-Tracker cooling systems. A special method for the fluid circulation is developed at Nikhef to get a very stable temperature of both detectors without any active components like valves or heaters inside. This method is called 2-phase Accumulator Controlled Loop (2PACL) and is a good candidate technology for the design of the future cooling systems for the Atlas and CMS upgrades.

  9. Electrochemical CO2 Reduction: A Classification Problem.

    Science.gov (United States)

    Bagger, Alexander; Ju, Wen; Varela, Ana Sofia; Strasser, Peter; Rossmeisl, Jan

    2017-11-17

    In this work, we propose four non-coupled binding energies of intermediates as descriptors, or "genes", for predicting the product distribution in CO2 electroreduction. Simple reactions can be understood by the Sabatier principle (catalytic activity vs. one descriptor), while more complex reactions tend to give multiple very different products and consequently the product selectivity is a more complex property to understand. We approach this, as a logistical classification problem, by grouping metals according to their major experimental product from CO2 electroreduction: H2 , CO, formic acid and beyond CO* (hydrocarbons or alcohols). We compare the groups in terms of multiple binding energies of intermediates calculated by density functional theory. Here, we find three descriptors to explain the grouping: the adsorption energies of H*, COOH*, and CO*. To further classify products beyond CO*, we carry out formaldehyde experiments on Cu, Ag, and Au and combine these results with the literature to group and differentiate alcohol or hydrocarbon products. We find that the oxygen binding (adsorption energy of CH3 O*) is an additional descriptor to explain the alcohol formation in reduction processes. Finally, the adsorption energy of the four intermediates, H*, COOH*, CO*, and CH3 O*, can be used to differentiate, group, and explain products in electrochemical reduction processes involving CO2 , CO, and carbon-oxygen compounds. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Biosequestration of atmospheric CO2 and flue gas-containing CO2 by microalgae.

    Science.gov (United States)

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

    2015-05-01

    The unceasing rise of greenhouse gas emission has led to global warming and climate change. Global concern on this phenomenon has put forward the microalgal-based CO2 sequestration aiming to sequester carbon back to the biosphere, ultimately reducing greenhouse effects. Microalgae have recently gained enormous attention worldwide, to be the valuable feedstock for renewable energy production, due to their high growth rates, high lipid productivities and the ability to sequester carbon. The photosynthetic process of microalgae uses atmospheric CO2 and CO2 from flue gases, to synthesize nutrients for their growth. In this review article, we will primarily discuss the efficiency of CO2 biosequestration by microalgae species, factors influencing microalgal biomass productions, microalgal cultivation systems, the potential and limitations of using flue gas for microalgal cultivation as well as the bio-refinery approach of microalgal biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Integration of the electrochemical depolorized CO2 concentrator with the Bosch CO2 reduction subsystem

    Science.gov (United States)

    Schubert, F. H.; Wynveen, R. A.; Hallick, T. M.

    1976-01-01

    Regenerative processes for the revitalization of spacecraft atmospheres require an Oxygen Reclamation System (ORS) for the collection of carbon dioxide and water vapor and the recovery of oxygen from these metabolic products. Three life support subsystems uniquely qualified to form such an ORS are an Electrochemical CO2 Depolarized Concentrator (EDC), a CO2 Reduction Subsystem (BRS) and a Water Electrolysis Subsystem (WES). A program to develop and test the interface hardware and control concepts necessary for integrated operation of a four man capacity EDC with a four man capacity BRS was successfully completed. The control concept implemented proved successful in operating the EDC with the BRS for both constant CO2 loading as well as variable CO2 loading, based on a repetitive mission profile of the Space Station Prototype (SSP).

  12. Natural Analogues of CO2 Geological Storage; Analogos Naturales del Almacenamiento Geologico de CO2

    Energy Technology Data Exchange (ETDEWEB)

    Perez del Villar, L.; Pelayo, M.; Recreo, F.

    2007-07-20

    Geological storage of carbon dioxide is nowadays, internationally considered as the most effective method for greenhouse gas emission mitigation, in order to minimize the global climate change universally accepted. Nevertheless, the possible risks derived of this long-term storage have a direct influence on its public acceptance. Among the favourable geological formations to store CO2, depleted oil and gas fields, deep saline reservoirs, and unamiable coal seams are highlighted. One of the most important objectives of the R and D projects related to the CO2 geological storage is the evaluation of the CO2 leakage rate through the above mentioned geological formations. Therefore, it is absolutely necessary to increase our knowledge on the interaction among CO2, storage and sealing formations, as well as on the flow paths and the physical resistance of the sealing formation. The quantification of the CO2 leakage rate is essential to evaluate the effects on the human and animal health, as well as for the ecosystem and water quality. To achieve these objectives, the study of the natural analogues is very useful in order to know the natural leakage rate to the atmosphere, its flow paths, the physical, chemical and mineralogical modifications due to the long term interaction processes among the CO2 and the storage and sealing formations, as well as the effects on the groundwaters and ecosystems. In this report, we have tried to summarise the main characteristics of the natural reservoirs and surficial sources of CO2, which are both natural analogues of the geological storage and CO2 leakage, studied in EEUU, Europe and Australia. The main objective of this summary is to find the possible applications for long-term risk prediction and for the performance assessment by means of conceptual and numerical modelling, which will allow to validate the predictive models of the CO2 storage behaviour, to design and develop suitable monitoring techniques to control the CO2 behaviour

  13. Increased reserves through horizontal drilling in a mature waterflood, Long Beach unit, Wilmington Oil Field, California

    Energy Technology Data Exchange (ETDEWEB)

    Berman, B.H. (Thums Long Beach Co., Long Beach, CA (United States))

    1996-01-01

    Ranger Zone development started in 1965. A waterflood was initiated from the start using a staggered line-drive pattern. Infill drilling in the early 1980s and again in the 1990s revealed bypassed oil in the upper Ranger Fo sand. Detailed studies of the aerial extent of the remaining oil resulted in drilling 17 horizontal wells to recover these reserves. The Fo target sand thickness is 20 to 50 feet. Well courses are between 10 and 15 feet below the top of the Fo with lengths varying from 800 to 1,000 feet. The success of the Fo drilling program has prompted expansion of horizontal drilling into thin-bedded sand units. Well lengths have increased to between 1,500 and 1,800 feet with structural trend used to advantage. Where needed, probes are designed to penetrate the target sand before setting intermediate casing. The drilling program has been extended into bilateral horizontal completions. Geosteering with MWD/GR and a 2 MHz dual propagation resistivity tool is used to the casing point. In the completion interval, only the MWD/GR tool is used and a drillpipe conveyed E-log is run afterward to confirm expected resistivities. Despite the many well penetrations in the Ranger Zone, structural control is only fair. Accuracy of MWD data is generally low and geosteering is done by TVD log correlation. With a recovery factor of over 30 percent in Ranger West, from approximately 800 wells drilled in the last 30 years, the horizontal drilling program targeting bypassed reserves has brought new life to this mature reservoir.

  14. Increased reserves through horizontal drilling in a mature waterflood, Long Beach unit, Wilmington Oil Field, California

    Energy Technology Data Exchange (ETDEWEB)

    Berman, B.H. [Thums Long Beach Co., Long Beach, CA (United States)

    1996-12-31

    Ranger Zone development started in 1965. A waterflood was initiated from the start using a staggered line-drive pattern. Infill drilling in the early 1980s and again in the 1990s revealed bypassed oil in the upper Ranger Fo sand. Detailed studies of the aerial extent of the remaining oil resulted in drilling 17 horizontal wells to recover these reserves. The Fo target sand thickness is 20 to 50 feet. Well courses are between 10 and 15 feet below the top of the Fo with lengths varying from 800 to 1,000 feet. The success of the Fo drilling program has prompted expansion of horizontal drilling into thin-bedded sand units. Well lengths have increased to between 1,500 and 1,800 feet with structural trend used to advantage. Where needed, probes are designed to penetrate the target sand before setting intermediate casing. The drilling program has been extended into bilateral horizontal completions. Geosteering with MWD/GR and a 2 MHz dual propagation resistivity tool is used to the casing point. In the completion interval, only the MWD/GR tool is used and a drillpipe conveyed E-log is run afterward to confirm expected resistivities. Despite the many well penetrations in the Ranger Zone, structural control is only fair. Accuracy of MWD data is generally low and geosteering is done by TVD log correlation. With a recovery factor of over 30 percent in Ranger West, from approximately 800 wells drilled in the last 30 years, the horizontal drilling program targeting bypassed reserves has brought new life to this mature reservoir.

  15. Miscible displacement by high-pressure gas at Block 31

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, J.H.; Robertson, N.

    1975-11-01

    The world's first large-scale miscible displacement project by high-pressure gas injection has produced 130,000,000 bbl, almost double the original estimated primary recovery of 69,000,000 bbl, at the University Block 31 field in Crane County, Texas. The field-wide project began in 1952, and will keep the unit on stream well into the future, with ultimate recovery efficiency estimated at 60%. Infill drilling has helped boost daily production to 16,000 bbl, highest producing rate since gas injection began in 1949. The subject discussed include reservoir characteristics, high pressure gas miscibility, flue gas generation, production problems, and new lift for an old field by infill drilling.

  16. Gas miscible displacement enhanced oil recovery: Technology status report

    Energy Technology Data Exchange (ETDEWEB)

    Watts, R.J.; Komar, C.A. (eds.)

    1989-01-01

    Research on gas flooding and miscible displacement, with an emphasis on improvement of CO/sub 2/ flood performance is described. Low reservoir volumetric sweep efficiency is the major problem associated with gas flooding and all miscible displacements. CO/sub 2/ flooding would be considerably more efficient if a larger area of the reservoir could be contacted by the gas. Current research has focused on mobility control, computer simulation, and reservoir heterogeneity studies. Three mobility control methods have been investigated: the use of polymers for direct thickening of high-density carbon dioxide, mobile ''foam-like dispersions'' of carbon dioxide and aqueous surfactant, and in situ deposition of chemical precipitates. 17 refs., 22 figs., 8 tabs.

  17. Global Approach for Calculation of Minimum Miscibility Pressure

    DEFF Research Database (Denmark)

    Jessen, Kristian; Michelsen, Michael Locht; Stenby, Erling Halfdan

    1998-01-01

    An algorithm has been developed for calculation of minimum miscibility pressure (MMP) for the displacement of oil by multicomponent gas injection. The algorithm is based on the key tie line identification approach initially addressed by Wang and Orr [Y. Wang and F.M. Orr Jr., Analytical calculation...... of minimum miscibility pressure, Fluid Phase Equilibria, 139 (1997) 101-124]. In this work a new global approach is introduced. A number of deficiencies of the sequential approach have been eliminated resulting in a robust and highly efficient algorithm. The time consumption for calculation of the MMP...... in multicomponent displacement processes has been reduced significantly and can now be performed within a few seconds on a PC for a 15-component gas mixture. The algorithm is hence particularly suitable for gas enrichment studies or other case studies where a large number of MMP calculations is required. Predicted...

  18. CO2-Responsive Polymer-Functionalized Au Nanoparticles for CO2 Sensor.

    Science.gov (United States)

    Ma, Ying; Promthaveepong, Kittithat; Li, Nan

    2016-08-16

    Metallic nanoparticles (NPs) coated with stimuli-responsive polymers (SRPs) exhibit tunable optical properties responding to external stimuli and show promising sensing applications. We present a new CO2-responsive polymer, poly(N-(3-amidino)-aniline) (PNAAN), coated gold NPs (AuNPs) synthesized by directly reducing HAuCl4 with a CO2-responsive monomer N-(3-amidino)-aniline (NAAN). The amidine group of PNAAN can be protonated into a hydrophilic amidinium group by dissolved CO2 (dCO2). This induces the PNAAN to swell and detach from the AuNP surface, resulting in AuNP aggregation and color change. By monitoring the UV absorbance change of AuNPs, a sensitive dCO2 sensor with a linear range of 0.0132 to 0.1584 hPa and a limit of detection (LOD) of 0.0024 hPa is developed. This method shows dramatic improvement in sensitivity and convenience of sample preparation compared with the previously reported dCO2 sensor.

  19. Recycling CO 2 ? Computational Considerations of the Activation of CO 2 with Homogeneous Transition Metal Catalysts

    KAUST Repository

    Drees, Markus

    2012-08-10

    Faced with depleting fossil carbon sources, the search for alternative energy carriers and energy storage possibilities has become an important issue. Nature utilizes carbon dioxide as starting material for storing sun energy in plant hydrocarbons. A similar approach, storing energy from renewable sources in chemical bonds with CO 2 as starting material, may lead to partial recycling of CO 2 created by human industrial activities. Unfortunately, currently available routes for the transformation of CO 2 involve high temperatures and are often not selective. With the development of more sophisticated methods and better software, theoretical studies have become both increasingly widespread and useful. This concept article summarizes theoretical investigations of the current state of the feasibility of CO 2 activation with molecular transition metal catalysts, highlighting the most promising reactions of CO 2 with olefins to industrially relevant acrylic acid/acrylates, and the insertion of CO 2 into metal-element bonds, particularly for the synthesis of cyclic carbonates and polymers. Rapidly improving computational power and methods help to increase the importance and accuracy of calculations continuously and make computational chemistry a useful tool helping to solve some of the most important questions for the future. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Effective Use of Natural CO2-RICH Systems for Stakeholder Communication: CO2FACTS.ORG

    Science.gov (United States)

    Olson, H. C.; Romanak, K.; Osborne, V.; Hovorka, S. D.; Clift, S.; Castner, A.

    2011-12-01

    The impact of using natural analogues as an avenue for communicating about CO2 injection and storage technology with stakeholders has been addressed by previous researchers, e.g., Romanak et al (2011), Dixon et al (2011). Analogies between natural CO2-rich systems and engineered CO2 storage are not necessarily straightforward, and stakeholder opinion is often based on factors other than technical accuracy of information (e.g., lack of trust, confidence, and fear). In order to enhance this communication pathway, STORE (Sequestration Training, Outreach, Research and Education), the outreach arm of the Gulf Coast Carbon Center at The University of Texas at Austin, has created an online resource (www.co2facts.org) to help stakeholders better understand the injection and storage of CO2 underground. The online resource includes frequently asked questions (FAQs) for a variety of CO2-storage-related issues, including those related to natural analogues, and uses examples of natural systems of CO2 release for communication. The content targets various levels of technical education and understanding. A unique feature of the online resource is its approach to verification of information. Each FAQ and example is "fact-checked" by an actual expert in the field. Part of this verification process is to provide an online link to background, credentials, scientific research and images of actual experts in the field at natural release sites. This approach helps put a face to, and potentially builds a relationship of trust with, the scientist behind the technical information. Videos of experts discussing natural systems and their similarities and differences with CO2 injection and storage sites are also part of the resource. Stakeholders commonly draw incorrect parallels between natural disasters that gain attention in the media (e.g., Lake Nyos) and CO2 injection and storage technology. The video images available at www.co2facts.org are a useful tool for assuaging environmental fears

  1. Metabolic effects of Carbon Dioxide (CO 2 ) insufflation during ...

    African Journals Online (AJOL)

    Metabolic effects of Carbon Dioxide (CO 2 ) insufflation during laparoscopic surgery: changes in pH, arterial partial Pressure of Carbon Dioxide (PaCo 2 ) and End Tidal Carbon Dioxide (EtCO ... EtCO2 is still a good non-invasive monitor for estimation of PaCO2 during low tidal volume ventilation during pneumoperitoneum.

  2. In silico screening of zeolite membranes for CO2 capture

    NARCIS (Netherlands)

    Krishna, R.; van Baten, J.M.

    2010-01-01

    The separation of CO2/H-2, CO2/CH4, and CO2/N-2 mixtures is of practical importance for CO2 capture and other applications in the processing industries. Use of membranes with microporous layers of zeolites, metal-organic frameworks (MOFs), and zeolitic imidazolate frameworks (ZIFs) offer

  3. Miscibility and oxidation rate of the simulated metallic spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    You, K. S.; Joo, J. S.; Shin, Y. J.; Oh, S. C. [KAERI, Taejon (Korea, Republic of)

    1999-10-01

    The simulated metallic spent fuel was fabricated by using Uranium, Neodymium and Palladium in order to study the miscibility of Neodymium and Palladium with Uranium. For analysis of long-term safty on the metallized spent fuel, the simulated metallic spent fuel was oxidized under pure oxygen environment at 183{approx}250 deg C. From the results, the oxidation rate correlation and activation energy were obtained.

  4. Colloidal rods and spheres in partially miscible binary liquids

    OpenAIRE

    Hijnen, Niek

    2013-01-01

    Different scenarios for assembling rod-like and spherical colloidal particles using binary mixtures of partially miscible liquids were investigated experimentally. Suitable rod-like colloids were developed first. The subsequent studies of colloids in binary liquids consisted, on one hand, of systems where particles were partially wetted by both phases and, on the other hand, of systems where particles were completely wetted by the minority phase. A simple method to prepare l...

  5. The liquid metastable miscibility gap in Cu-based systems

    DEFF Research Database (Denmark)

    Curiotto, S.; Greco, R.; Pryds, Nini

    2007-01-01

    Some Cu-based alloys, like Cu–Co, Cu–Fe and Cu–Co–Fe, display a liquid metastable miscibility gap. When the melt is undercooled below a certain temperature depending on the alloy composition, they present a separation in two liquid phases, followed by coagulation before dendritic solidification. ....... Furthermore, the knowledge on the phase equilibria in the three systems is extended by presenting new results obtained by differential scanning calorimetry (DSC) and comparing them with the calculated phase diagrams....

  6. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, Roy; Clarke, Don; Walker, Scott; Phillips, Chris; Nguyen, John; Moos, Dan; Tagbor, Kwasi

    2001-08-07

    This project was intended to increase recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs, transferring technology so that it can be applied in other sections of the Wilmington field and by operators in other slope and basin reservoirs is a primary component of the project.

  7. Carbon Sequestration: Hydrogenation of CO2 to Formic Acid

    Directory of Open Access Journals (Sweden)

    Upadhyay Praveenkumar

    2016-10-01

    Full Text Available The concentration CO2 gas has become a great worldwide challenge because CO2 is considered as an important counterpart of greenhouse gases. The tremendous increase in the concentration of CO2 gas, elevated the worldwide temperature as well as it altered the climatic changes. Various physiochemical approached have been reported to trap the CO2 gas and the chemical conversion of CO2 to useful chemicals is one of them. This review covers the conversion of CO2 gas to formic acid. In this CO2 hydrogenation reaction, both the homogeneous as well as heterogeneous catalytic systems were discussed along with the effect of solvent systems on reaction kinetics.

  8. Regimes of miscible fluid thread formation in microfluidic focusing sections

    Science.gov (United States)

    Cubaud, Thomas; Notaro, Sara

    2014-12-01

    We experimentally study the formation and stability of miscible fluid threads made of high-viscosity liquids using hydrodynamic focusing sections. Miscible core annular flows are useful for transporting viscous materials and can be destabilized for enhancing mass transfer. We delineate phase-diagrams of the generation of lubricated threads from low to large viscosity contrasts with various diffusion coefficients. Depending on fluid properties and flow rates of injection, stable microflows are classified into engulfment, thread, and tubing regimes. For low Péclet numbers, we examine thread dynamics when diffusive effects strongly alter basic flow structures and induce new flow configurations, including ultra-diffusive and diffusive instability regimes. Another unstable flow arrangement is investigated for moderate Reynolds numbers where small threads are rapidly destabilized in the inertial flow field of the sheath fluid near the fluid junction. This study provides an overview of stable and unstable flow regimes and their transitions during the formation of miscible viscous fluid filaments in square microchannels.

  9. Miscibility Studies on Polymer Blends Modified with Phytochemicals

    Science.gov (United States)

    Chandrasekaran, Neelakandan; Kyu, Thein

    2009-03-01

    The miscibility studies related to an amorphous poly(amide)/poly(vinyl pyrrolidone) [PA/PVP] blend with a crystalline phytochemical called ``Mangiferin'' is presented. Phytochemicals are plant derived chemicals which intrinsically possess multiple salubrious properties that are associated with prevention of diseases such as cancer, diabetes, cardiovascular disease, and hypertension. Incorporation of phytochemicals into polymers has shown to have very promising applications in wound healing, drug delivery, etc. The morphology of these materials is crucial to applications like hemodialysis, which is governed by thermodynamics and kinetics of the phase separation process. Hence, miscibility studies of PA/PVP blends with and without mangiferin have been carried out using dimethyl sulfoxide as a common solvent. Differential scanning calorimetry studies revealed that the binary PA/PVP blends were completely miscible at all compositions. However, the addition of mangiferin has led to liquid-liquid phase separation and liquid-solid phase transition in a composition dependent manner. Fourier transformed infrared spectroscopy was undertaken to determine specific interaction between the polymer constituents and the role of possible hydrogen bonding among three constituents will be discussed.

  10. Miscible displacement in the Weyburn reservoir: A laboratory study

    Energy Technology Data Exchange (ETDEWEB)

    Huang, S.S (Saskatchewan Research Council, Saskatoon, SK (Canada)); Dyer, S.B. (PanCanadian Petorleum Ltd., AB (Canada))

    1993-09-01

    A laboratory study was conducted to evaluate the applicability of various solvents (including the potential source of carbon dioxide extracted from flue gas) for the recovery of oil from a southeast Saskatchewan reservoir, the Weyburn. The physical, chemical, and phase behavior (PVT) properties of the dead oil, reservoir fluid, and reservoir fluid with carbon dioxide, were determined. Slim tube tests were conducted for the Weyburn reservoir fluid with pure carbon dioxide, with wellhead gas from the Steelman gas plant, and with two impure carbon dioxide gases (one containing 9.9 mol % CH[sub 4] and the other containing 5.1 mol % N[sub 2] and 5.1 mol % CH[sub 4]), at various pressures and the reservoir temperature of 59[degree]C. Tests were also carried out to determine the maximum amount of impurities that can be tolerated for the miscible process. The minimum miscibility pressures (MMP) determined for the systems demonstrated that miscible displacement using pure CO[sub 2] or impure gas containing up to 9.9 mol % CH[sub 4] as a solvent is a promising enhanced oil recovery (EOR) technique for southest Saskatchewan reservoirs. The MMPs are below the estimated reservoir fracture pressure. The wellhead gas from the Steelman gas plant is not a suitable EOR agent for the Weyburn reservoir. MMPs determined by the rising bubble method were in good agreement with slim tube test results, and this method is considered superior. 20 refs., 8 figs., 15 tabs.

  11. Air-sea CO2 fluxes along the coast of Chile: From CO2 outgassing in central northern upwelling waters to CO2 uptake in southern Patagonian fjords

    Science.gov (United States)

    Torres, Rodrigo; Pantoja, Silvio; Harada, Naomi; GonzáLez, Humberto E.; Daneri, Giovanni; Frangopulos, MáXimo; Rutllant, José A.; Duarte, Carlos M.; Rúiz-Halpern, Sergio; Mayol, Eva; Fukasawa, Masao

    2011-09-01

    Carbon system parameters measured during several expeditions along the coast of Chile (23°S-56°S) have been used to show the main spatial and temporal trends of air-sea CO2 fluxes in the coastal waters of the eastern South Pacific. Chilean coastal waters are characterized by strong pCO2 gradients between the atmosphere and the surface water, with high spatial and temporal variability. On average, the direction of the carbon flux changes from CO2 outgassing at the coastal upwelling region to CO2 sequestering at the nonupwelling fjord region in Chilean Patagonia. Estimations of surface water pCO2 along the Patagonian fjord region showed that, while minimum pCO2 levels (strong CO2 undersaturation) occurs during the spring and summer period, maximum levels (including CO2 supersaturation) occur during the austral winter. CO2 uptake in the Patagonia fjord region during spring-summer is within the order of -5 mol C m-2 yr-1, indicating a significant regional sink of atmospheric CO2 during that season. We suggest that the CO2 sink at Patagonia most probably exceeds the CO2 source exerted by the coastal upwelling system off central northern Chile.

  12. PLAINS CO2 REDUCTION (PCOR) PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Edward N. Steadman; Daniel J. Daly; Lynette L. de Silva; John A. Harju; Melanie D. Jensen; Erin M. O' Leary; Wesley D. Peck; Steven A. Smith; James A. Sorensen

    2006-01-01

    During the period of October 1, 2003, through September 30, 2005, the Plains CO2 Reduction (PCOR) Partnership, identified geologic and terrestrial candidates for near-term practical and environmentally sound carbon dioxide (CO2) sequestration demonstrations in the heartland of North America. The PCOR Partnership region covered nine states and three Canadian provinces. The validation test candidates were further vetted to ensure that they represented projects with (1) commercial potential and (2) a mix that would support future projects both dependent and independent of CO2 monetization. This report uses the findings contained in the PCOR Partnership's two dozen topical reports and half-dozen fact sheets as well as the capabilities of its geographic information system-based Decision Support System to provide a concise picture of the sequestration potential for both terrestrial and geologic sequestration in the PCOR Partnership region based on assessments of sources, sinks, regulations, deployment issues, transportation, and capture and separation. The report also includes concise action plans for deployment and public education and outreach as well as a brief overview of the structure, development, and capabilities of the PCOR Partnership. The PCOR Partnership is one of seven regional partnerships under Phase I of the U.S. Department of Energy National Energy Technology Laboratory's Regional Carbon Sequestration Partnership program. The PCOR Partnership, comprising 49 public and private sector members, is led by the Energy & Environmental Research Center at the University of North Dakota. The international PCOR Partnership region includes the Canadian provinces of Alberta, Saskatchewan, and Manitoba and the states of Montana (part), Wyoming (part), North Dakota, South Dakota, Nebraska, Missouri, Iowa, Minnesota, and Wisconsin.

  13. Method for tracing simulated CO2 leak in terrestrial environment with a 13CO2 tracer

    Science.gov (United States)

    Moni, Christophe; Rasse, Daniel

    2013-04-01

    Facilities for the geological storage of carbon dioxide (CO2) as part of carbon capture and storage (CCS) schemes will be designed to prevent any leakage from the defined 'storage complex'. However, developing regulations and guidance throughout the world (e.g. the EC Directive and the USEPA Vulnerability Evaluation Framework) recognize the importance of assessing the potential for environmental impacts from CO2 storage. RISCS, a European (FP7) project, aims to improve understanding of those impacts that could plausibly occur in the hypothetical case that unexpected leakage occurs. As part of the RISCS project the potential impacts that an unexpected CO2 leaks might have on a cropland ecosystems was investigated. A CO2 exposure field experiment based on CO2 injection at 85 cm depth under an oats culture was designed. To facilitate the characterization of the simulated leaking zone the gas used for injection was produced from natural gas and had a δ13C of -46‰. The aim of the present communication is to depict how the injected gas was traced within the soil-vegetation-atmosphere continuum using 13CO2 continuous cavity ring-down spectrometry (CRDS). Four subsurface experimental injection plots (6m x 3m) were set up. In order to test the effects of different intensity of leakage, the field experiment was designed as to create a longitudinal CO2 gradient for each plot. For this purpose gas supply pipes were inserted at one extremity of each plot at the base of a 45 cm thick layer of sand buried 40 cm below the surface under the clayey plough layer of Norwegian moraine soils. Soil CO2 concentration and isotopic signature were punctually recorded: 1) in the soil at 20 cm depth at 6 positions distributed on the central transect, 2) at the surface following a (50x50 cm) grid sampling pattern, and 3) in the canopy atmosphere at 10, 20, 30 cm along three longitudinal transects (seven sampling point per transect). Soil CO2 fluxes and isotopic signature were finally

  14. Upscaling of enzyme enhanced CO2 capture

    DEFF Research Database (Denmark)

    Gladis, Arne Berthold

    Fossil fuels are the backbone of the energy generation in the coming decades for USA, China, India and Europe, hence high greenhouse gas emissions are expected in future. Carbon capture and storage technology (CCS) is the only technology that can mitigate greenhouse gas emissions from fossil fuel...... fired power by selectively capturing CO2 from flue gases. High capital and high operational costs of this process are the major obstacles of industrial implementation. In the field of CCS the chemical absorption process is the most mature technology. The use of kinetic rate promoters that enhance...

  15. Chilled ammonia process for CO2 capture

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Thomsen, Kaj; van Well, Willy J. M

    2009-01-01

    The chilled ammonia process absorbs the CO2 at low temperature (2-10 degrees C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows...... C and pressure up to 100 bars [1]. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The energy requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that an energy requirement for the desorber...

  16. Saturated CO2 inhibits microbial processes in CO2-vented deep-sea sediments

    Directory of Open Access Journals (Sweden)

    D. de Beer

    2013-08-01

    Full Text Available This study focused on biogeochemical processes and microbial activity in sediments of a natural deep-sea CO2 seepage area (Yonaguni Knoll IV hydrothermal system, Japan. The aim was to assess the influence of the geochemical conditions occurring in highly acidic and CO2 saturated sediments on sulfate reduction (SR and anaerobic methane oxidation (AOM. Porewater chemistry was investigated from retrieved sediment cores and in situ by microsensor profiling. The sites sampled around a sediment-hosted hydrothermal CO2 vent were very heterogeneous in porewater chemistry, indicating a complex leakage pattern. Near the vents, droplets of liquid CO2 were observed emanating from the sediments, and the pH reached approximately 4.5 in a sediment depth > 6 cm, as determined in situ by microsensors. Methane and sulfate co-occurred in most sediment samples from the vicinity of the vents down to a depth of 3 m. However, SR and AOM were restricted to the upper 7–15 cm below seafloor, although neither temperature, low pH, nor the availability of methane and sulfate could be limiting microbial activity. We argue that the extremely high subsurface concentrations of dissolved CO2 (1000–1700 mM, which disrupt the cellular pH homeostasis, and lead to end-product inhibition. This limits life to the surface sediment horizons above the liquid CO2 phase, where less extreme conditions prevail. Our results may have to be taken into consideration in assessing the consequences of deep-sea CO2 sequestration on benthic element cycling and on the local ecosystem state.

  17. Choice of satellite-based CO2 product (XCO¬2, vertical profile) alters surface CO2 flux estimate

    Science.gov (United States)

    Liu, J.; Bowman, K. W.; Lee, M.; Henze, D. K.; Fisher, J. B.; Frankenberg, C.; Polhamus, A.

    2011-12-01

    The ACOS (Atmospheric CO2 Observations from Space) algorithm provides column-averaged CO2 products in units of dry-air mole fraction (XCO2) based on GOSAT radiances. However, XCO2 is derived from a linear transformation of the CO2 vertical profiles estimated from the ACOS retrieval algorithm. In theory, XCO2 vertical columns should provide no more information than the original CO2 profiles. However, the different sensitivities of either CO2 profiles or XCO2 to transport errors can significantly alter surface CO2 flux estimates. Though it has been argued that XCO2 may be less sensitive to transport error than CO2 vertical profiles, there is no study so far investigating the actual impact on surface CO2 flux estimation due to the choice of observation format, which could have significant impact on future satellite CO2 profile mission concepts. In this presentation, we will present the sensitivity of surface CO2 flux estimation to a suite of CO2 observation products, which includes CO2 vertical profiles, XCO2, and the lowest 3 levels of CO2 from CO2 vertical profiles. The CO2 observations are ACOS products covering from July 2009 to June 2010. We will present both OSSE and real observation experiments. In the OSSE experiments, we will present both perfect model experiments and experiments with model errors that are introduced by changing the planetary boundary height. In the real observations, we will show the annual and seasonal CO2 flux as function of regions from using the three observation products. The accuracy of CO2 flux estimation will be examined by comparing CO2 concentrations forced by posterior CO2 flux to independent CO2 observations. The surface CO2 flux estimation framework is based on GEOS-Chem adjoint model that is developed by the Carbon Monitoring Study flux pilot project.

  18. CO2 acclimation impacts leaf isoprene emissions: evidence from past to future CO2 levels

    Science.gov (United States)

    de Boer, Hugo; van der Laan, Annick; Dekker, Stefan; Holzinger, Rupert

    2017-04-01

    Isoprene is emitted by many plant species as a side-product of photosynthesis. Once in the atmosphere, isoprene exhibits climate forcing through various feedback mechanisms. In order to quantify the climate feedbacks of biogenic isoprene emission it is crucial to establish how isoprene emissions are effected by plant acclimation to rising atmospheric CO2 levels. A promising development for modelling CO2-induced changes in isoprene emissions is the Leaf-Energetic-Status model (referred to as LES-model hereafter, see Harrison et al., 2013 and Morfopoulos et al., 2014). This model simulates isoprene emissions based on the hypothesis that isoprene biosynthesis depends on the imbalance between the photosynthetic electron supply of reducing power and the electron demands of carbon fixation. The energetic imbalance is critically related to the photosynthetic electron transport capacity (Jmax) and the maximum carboxylation capacity of Rubisco (Vcmax). Here we compare predictions of the LES-model with observed isoprene emission responses of Quercus robur (pedunculate oak) specimen that acclimated to CO2 growth conditions representative of the last glacial, the present and the end of this century (200, 400 and 800 ppm, respectively) for two growing seasons. These plants were grown in walk-in growth chambers with tight control of light, temperature, humidity and CO2 concentrations. Photosynthetic biochemical parameters Vcmax and Jmax were determined with a Licor LI-6400XT photosynthesis system. The relationship between photosynthesis and isoprene emissions was measured by coupling the photosynthesis system with a Proton-Transfer Reaction Time-of-Flight Mass Spectrometer. Our empirical results support the LES-model and show that the fractional allocation of carbon to isoprene biosynthesis is reduced in response to both short-term and long-term CO2 increases. In the short term, an increase in CO2 stimulates photosynthesis through an increase in the leaf interior CO2

  19. Global CO2 emissions from cement production

    Science.gov (United States)

    Andrew, Robbie M.

    2018-01-01

    The global production of cement has grown very rapidly in recent years, and after fossil fuels and land-use change, it is the third-largest source of anthropogenic emissions of carbon dioxide. The required data for estimating emissions from global cement production are poor, and it has been recognised that some global estimates are significantly inflated. Here we assemble a large variety of available datasets and prioritise official data and emission factors, including estimates submitted to the UNFCCC plus new estimates for China and India, to present a new analysis of global process emissions from cement production. We show that global process emissions in 2016 were 1.45±0.20 Gt CO2, equivalent to about 4 % of emissions from fossil fuels. Cumulative emissions from 1928 to 2016 were 39.3±2.4 Gt CO2, 66 % of which have occurred since 1990. Emissions in 2015 were 30 % lower than those recently reported by the Global Carbon Project. The data associated with this article can be found at https://doi.org/10.5281/zenodo.831455" target="_blank">https://doi.org/10.5281/zenodo.831455.

  20. Public Acceptance for Geological CO2-Storage

    Science.gov (United States)

    Schilling, F.; Ossing, F.; Würdemann, H.; Co2SINK Team

    2009-04-01

    Public acceptance is one of the fundamental prerequisites for geological CO2 storage. In highly populated areas like central Europe, especially in the vicinity of metropolitan areas like Berlin, underground operations are in the focus of the people living next to the site, the media, and politics. To gain acceptance, all these groups - the people in the neighbourhood, journalists, and authorities - need to be confident of the security of the planned storage operation as well as the long term security of storage. A very important point is to show that the technical risks of CO2 storage can be managed with the help of a proper short and long term monitoring concept, as well as appropriate mitigation technologies e.g adequate abandonment procedures for leaking wells. To better explain the possible risks examples for leakage scenarios help the public to assess and to accept the technical risks of CO2 storage. At Ketzin we tried the following approach that can be summed up on the basis: Always tell the truth! This might be self-evident but it has to be stressed that credibility is of vital importance. Suspiciousness and distrust are best friends of fear. Undefined fear seems to be the major risk in public acceptance of geological CO2-storage. Misinformation and missing communication further enhance the denial of geological CO2 storage. When we started to plan and establish the Ketzin storage site, we ensured a forward directed communication. Offensive information activities, an information centre on site, active media politics and open information about the activities taking place are basics. Some of the measures were: - information of the competent authorities through meetings (mayor, governmental authorities) - information of the local public, e.g. hearings (while also inviting local, regional and nation wide media) - we always treated the local people and press first! - organizing of bigger events to inform the public on site, e.g. start of drilling activities (open

  1. Effect of CO2 partial pressure and different CO2 phases on carbon steel corrosion

    Science.gov (United States)

    Mahlobo, MGR; Premlall, K.; Olubambi, PA

    2017-12-01

    Carbon capture and storage (CCS) is the recent promising technology aimed at reducing greenhouse gas emission. Like many other developed technologies, CCS is faced with great challenges such as pipeline transportation failure due to corrosion. There are many factors contributing to steel corrosion during the pipeline transportation of carbon dioxide (CO2). This study focuses on CO2 partial pressure and different phases of CO2 as some of the factors contributing to steel corrosion. Carbon steel was used as a testing specimen. High pressure reactor was used in this study to compress CO2 from low to high pressures ultimately changing the CO2 from gaseous phase to gas/liquid phase (subcritical) and to dense phase (supercritical). Weight loss method was employed to determine the corrosion rate while scanning electron microscopy (SEM) and X-Ray diffraction (XRD) were used to study the carbon steel morphology and phase analysis. Using low magnification digital camera, the type of corrosion that took place on the carbon steel surface was identified.

  2. Intermittent Water Injection on Top of Continuous CO2 Injection to Co-Optimize Oil Recovery and CO2-Storage

    OpenAIRE

    Pranoto, Arif

    2016-01-01

    Master's thesis in Petroleum engineering The objective of this project is to maximize oil recovery and the CO2 stored during CO2-EOR. To reach that goal there are two important things to be achieved: gas production rate reduction and the oil production rate improvement. To attain the co-optimization, the following CO2 injection approaches were compared: CO2 continuous injection, WAG, Continuous water injection over continuous CO2 injection, and intermittent water injection over continuous ...

  3. The Influence of CO2 Solubility in Brine on Simulation of CO2 Injection into Water Flooded Reservoir and CO2 WAG

    DEFF Research Database (Denmark)

    Yan, Wei; Stenby, Erling Halfdan

    2010-01-01

    Injection of CO2 into depleted oil reservoirs is not only a traditional way to enhance oil recovery but also a relatively cheaper way to sequester CO2 underground since the increased oil production can offset some sequestration cost. CO2 injection process is often applied to water flooded...... reservoirs and in many situations alternating injection of water and CO2 is required to stabilize the injection front. Both scenarios involve a large amount of water, making CO2 solubility in brine, which is around ten times higher than methane solubility, a non-negligible factor in the relevant reservoir...... simulations. In our previous study, a 1-D slimtube simulator, which rigorously accounts for both CO2 solubility in brine and water content in hydrocarbon phases using the Peng-Robinson EoS modified by Soreide and Whitson, has been used to investigate the influence of CO2 solubility on the simulation...

  4. Field demonstration of CO2 leakage detection in potable aquifers with a pulselike CO2-release test.

    Science.gov (United States)

    Yang, Changbing; Hovorka, Susan D; Delgado-Alonso, Jesus; Mickler, Patrick J; Treviño, Ramón H; Phillips, Straun

    2014-12-02

    This study presents two field pulselike CO2-release tests to demonstrate CO2 leakage detection in a shallow aquifer by monitoring groundwater pH, alkalinity, and dissolved inorganic carbon (DIC) using the periodic groundwater sampling method and a fiber-optic CO2 sensor for real-time in situ monitoring of dissolved CO2 in groundwater. Measurements of groundwater pH, alkalinity, DIC, and dissolved CO2 clearly deviated from their background values, showing responses to CO2 leakage. Dissolved CO2 observed in the tests was highly sensitive in comparison to groundwater pH, DIC, and alkalinity. Comparison of the pulselike CO2-release tests to other field tests suggests that pulselike CO2-release tests can provide reliable assessment of geochemical parameters indicative of CO2 leakage. Measurements by the fiber-optic CO2 sensor, showing obvious leakage signals, demonstrated the potential of real-time in situ monitoring of dissolved CO2 for leakage detection at a geologic carbon sequestration (GCS) site. Results of a two-dimensional reactive transport model reproduced the geochemical measurements and confirmed that the decrease in groundwater pH and the increases in DIC and dissolved CO2 observed in the pulselike CO2-release tests were caused by dissolution of CO2 whereas alkalinity was likely affected by carbonate dissolution.

  5. CO2 Emissions from Fuel Combustion - 2012 Highlights

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    How much CO2 are countries emitting? Where is it coming from? In the lead-up to the UN climate negotiations in Doha, the latest information on the level and growth of CO2 emissions, their source and geographic distribution will be essential to lay the foundation for a global agreement. To provide input to and support for the UN process the IEA is making available for free download the 'Highlights' version of CO2 Emissions from Fuel Combustion. This annual publication contains: estimates of CO2 emissions by country from 1971 to 2010; selected indicators such as CO2/GDP, CO2/capita, CO2/TPES and CO2/kWh; and CO2 emissions from international marine and aviation bunkers, and other relevant information.

  6. Photocatalytic Reduction of Low Concentration of CO2.

    Science.gov (United States)

    Nakajima, Takuya; Tamaki, Yusuke; Ueno, Kazuki; Kato, Eishiro; Nishikawa, Tetsuya; Ohkubo, Kei; Yamazaki, Yasuomi; Morimoto, Tatsuki; Ishitani, Osamu

    2016-10-05

    A novel molecular photocatalytic system with not only high reduction ability of CO2 but also high capture ability of CO2 has been developed using a Ru(II)-Re(I) dinuclear complex as a photocatalyst. By using this photocatalytic system, CO2 of 10% concentration could be selectively converted to CO with almost same photocatalysis to that under a pure CO2 atmosphere (TONCO > 1000, ΦCO > 0.4). Even 0.5% concentration of CO2 was reduced with 60% initial efficiency of CO formation by using the same system compared to that using pure CO2 (TONCO > 200). The Re(I) catalyst unit in the photocatalyst can efficiently capture CO2, which proceeds CO2 insertion to the Re-O bond, and then reduce the captured CO2 by using an electron supplied from the photochemically reduced Ru photosensitizer unit.

  7. CO(2) Inhibits Respiration in Leaves of Rumex crispus L.

    Science.gov (United States)

    Amthor, J S; Koch, G W; Bloom, A J

    1992-02-01

    Curly dock (Rumex crispus L.) was grown from seed in a glasshouse at an ambient CO(2) partial pressure of about 35 pascals. Apparent respiration rate (CO(2) efflux in the dark) of expanded leaves was then measured at ambient CO(2) partial pressure of 5 to 95 pascals. Calculated intercellular CO(2) partial pressure was proportional to ambient CO(2) partial pressure in these short-term experiments. The CO(2) level strongly affected apparent respiration rate: a doubling of the partial pressure of CO(2) typically inhibited respiration by 25 to 30%, whereas a decrease in CO(2) elicited a corresponding increase in respiration. These responses were readily reversible. A flexible, sensitive regulatory interaction between CO(2) (a byproduct of respiration) and some component(s) of heterotrophic metabolism is indicated.

  8. CO2 Emissions from Fuel Combustion 2011: Highlights

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    How much CO2 are countries emitting? Where is it coming from? In the lead-up to the UN climate negotiations in Durban, the latest information on the level and growth of CO2 emissions, their source and geographic distribution will be essential to lay the foundation for a global agreement. To provide input to and support for the UN process the IEA is making available for free download the 'Highlights' version of CO2 Emissions from Fuel Combustion. This annual publication contains: - estimates of CO2 emissions by country from 1971 to 2009; - selected indicators such as CO2/GDP, CO2/capita, CO2/TPES and CO2/kWh; - CO2 emissions from international marine and aviation bunkers, and other relevant information. These estimates have been calculated using the IEA energy databases and the default methods and emission factors from the Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories.

  9. Reducing CO2 from shipping – do non-CO2 effects matter?

    Directory of Open Access Journals (Sweden)

    M. S. Eide

    2013-04-01

    Full Text Available Shipping is a growing sector in the global economy, and it contributions to global CO2 emissions are expected to increase. CO2 emissions from the world shipping fleet will likely be regulated in the near future, and studies have shown that significant emission reductions can be achieved at low cost. Regulations are being discussed for both existing ships as well as for future additions to the fleet. In this study a plausible CO2 emission reduction inventory is constructed for the cargo fleet existing in 2010, as well as for container ships, bulk ships and tankers separately. In the reduction inventories, CO2 emissions are reduced by 25–32% relative to baseline by applying 15 technical and operational emission reduction measures in accordance with a ship-type-specific cost-effectiveness criterion, and 9 other emission compounds are changed as a technical implication of reducing CO2. The overall climate and environmental effects of the changes to all 10 emission components in the reduction inventory are assessed using a chemical transport model, radiative forcing (RF models and a simple climate model. We find substantial environmental and health benefits with up to 5% reduction in surface ozone levels, 15% reductions in surface sulfate and 10% reductions in wet deposition of sulfate in certain regions exposed to heavy ship traffic. The major ship types show distinctly different contributions in specific locations. For instance, the container fleet contributes 50% of the sulfate decline on the west coast of North America. The global radiative forcing from a 1 yr emission equal to the difference between baseline and reduction inventory shows an initial strong positive forcing from non-CO2 compounds. This warming effect is due to reduced cooling by aerosols and methane. After approximately 25 yr, the non-CO2 forcing is balanced by the CO2 forcing. For the global mean temperature change, we find a shift from warming to cooling after approximately 60

  10. Supercritical CO2 as a substitute of volatile hydrocarbons; Superkritisch CO2 vervangt vluchtige koolwaterstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Folkerts, G. (ed.)

    2006-05-15

    In many cases supercritical carbon dioxide can replace volatile hydrocarbons in extraction processes. Currently gaseous or liquid CO2 is already used for industrial purification processes, extraction of caffeine from coffee and as a solvent for paint. Although supercritical extraction s a batch process the technique can be applied as a continuous process. [Dutch] In processen waar vluchtige koolwaterstoffen worden ingezet om stoffen te extraheren, biedt superkritisch CO2 een milieuvriendelijk alternatief. Het koolzuur dat zowel in de vloeistof- als gasfase zit, wordt dan ook steeds meer ingezet in extractieprocessen.

  11. Responses of soil CO2 efflux to changes in plant CO2 uptake and transpiration

    Science.gov (United States)

    Balogh, János; de Luca, Giulia; Mészáros, Ádám; Trieber, Júlia; Gecse, Bernadett; Fóti, Szilvia; Pintér, Krisztina; Nagy, Zoltán

    2017-04-01

    Biotic drivers of soil respiration represent a significant supply-side (plant) control of the process. Those biotic drivers that integrate over longer time periods are useful in describing the phenological changes and physiological state of the vegetation, but they are not suitable to explain the diel variability of soil respiration. Two plant physiological processes, acting in opposite directions, could be relevant at diel timescale: (1) photosynthesis, and (2) transpiration. Firstly, it was recently found that photosynthesis has a time-lagged (a few hours) positive effect on the respiration of roots and root-associated microbes. This can be explainedby an increase in easily accessible non-structural hydrocarbon sources for the roots and root-associated organisms within this period. Secondly, it was found that the effect of transpiration could reduce root respiration due to CO2 transport through the transpiration stream, and this effect is expected to be immediate. Removing the effect of the abiotic drivers from the soil efflux signal could help to clarify the role of other driving variables. In the present study, we conducted manipulation measurements in lab environment to be able to detect the effects of the plant physiological variables (CO2 uptake, transpiration) on soil CO2 efflux. Plant individuals were planted into field soil samples in small pots. Transpiration manipulation was done by regulating vapour pressure of the air around the plant canopy and by inhibitors. Photosynthesis manipulation consisted of programmed absence of light. Isotopic signatures of soil respiration were used for estimating the contribution of the autotrophic and heterotrophic soil respiration components. 13CO2 concentration of the CO2 efflux of the different soil components was measured continuously in open system by cavity ring-down spectroscopy (Picarro G1101-i gas analyser). Keeling-plot approach was also used to calculate the isotopic signals of the sources. According to the

  12. Nanoscale Controls on CO2-water-rock Interactions in Saline Reservoirs

    Science.gov (United States)

    Deyoreo, J.; Depaolo, D. J.

    2009-12-01

    It is becoming increasingly widely recognized that geologic sequestration of CO2, when combined with economical means of capture, may be one of the most effective approaches to reducing net CO2 emissions to the atmosphere over the next century. Injection of CO2 into saline geologic formations involves forcing a buoyant, low-viscosity fluid into a more dense, higher viscosity fluid. The difference in wetting properties of the two fluids, their partial miscibility, the fact that CO2 and H2O form an acid, and the heterogeneity of geologic formations combine to make the flow and transport details fascinating but difficult to fully characterize and predict. A major question is whether the flow of CO2 into subsurface formations, the efficiency of pore space filling, and the trapping efficiency can be not only predicted but controlled over the decades of injection that might be associated with the life of a power plant. The major technological gaps to controlling and ultimately sequestering subsurface CO2 can be traced to far-from-equilibrum processes that originate at the molecular and nanoscale, but are expressed as complex emergent behavior at larger scales. Essential knowledge gaps involve the effects of nanoscale confinement on material properties, flow and chemical reactions, the effects of nanoparticles, mineral surface dynamics, and microbiota on mineral dissolution/precipitation and fluid flow, and the dynamics of fluid-fluid and fluid-mineral interfaces. To address these scientific and technical challenges, the Energy Frontier Research Center recently established, involving collaboration between LBNL, ORNL, MIT, UC Berkeley, UC Davis and LLNL, will attempt to bring new approaches to the study of nanoscale phenomena in fluid-rock systems to bear on the problem of CO2 behavior in saline formations. The stated goal is to use molecular, nanoscale, and pore-network scale approaches to control flow, dissolution, and precipitation in deep subsurface rock formations to

  13. Characterization of heavy oils. 3: Prediction of gas injection behavior -- Swelling test, multicontact test, multiple-contact minimum miscibility pressure, and multiple-contact minimum miscibility enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Jaubert, J.N. [Ecole Nationale Superieure des Industries Chimiques, Nancy (France); Neau, E.; Avaullee, L. [Faculte des Sciences de Luminy, Marseille (France). Lab. de Chimie Physique; Zaborowski, G. [Compagnie Petroliere TOTAL, Saint-Remy-les-Chevreuse (France). Centre Scientifique et Technique

    1995-11-01

    The modeling of miscible gas injection into reservoir crude oils was performed using a cubic equation of state coupled with a predictive procedure for characterizing the heavy fractions. It is shown that experimental data on the swelling test, multicontact test, slim tube minimum miscibility pressure (MMP), and minimum miscibility enrichment (MME) for 10 different crude oils from different fields are satisfactorily calculated using the predictive characterization. However, in the case of MMP and MME calculations, a significant deviation may appear between predicted and experimental values. Reasons for this discrepancy are discussed. The influence of tuning the equation of state parameters in the estimation of results for the swelling test is also discussed.

  14. Plasma Arc Augmented CO2 laser welding

    DEFF Research Database (Denmark)

    Bagger, Claus; Andersen, Mikkel; Frederiksen, Niels

    2001-01-01

    In order to reduce the hardness of laser beam welded 2.13 mm medium strength steel CMn 250, a plasma arc has been used simultaneously with a 2.6 kW CO2 laser source. In a number of systematic laboratory tests, the plasma arc current, plasma gas flow and distance to the laser source were varied...... with all laser parameters fixed. The welds were quality assessed and hardness measured transversely to the welding direction in the top, middle and root of the seam. In the seams welded by laser alone, hardness values between 275 and 304 HV1 were measured, about the double of the base material, 150 HV1...

  15. High gain, multiatmosphere CO2 laser amplifier

    Science.gov (United States)

    Stuart, G. C.; Houtman, H.; Meyer, J.

    1987-02-01

    A novel TE discharge, 15-mm aperture, multiatmosphere, CO2 laser amplifier is described, with measured electrical characteristics and gain measurements on the 9.294-micron, 9R (16) line. The electrical circuit used in this amplifier is a realistic alternative to the Marx bank or conventional LC inversion circuit and, similarly, it would be useful for excitation of other gas lasers as well. This automatically preionized, double-sided, fourfold LC inversion circuit uses only one spark gap, and it is shown to provide small-signal gains of 5.7 percent/cm, at 120 J/l atm and 10 atm. The generalization to an n-stage device, which would be suitable for higher pressures, and larger apertures, is discussed.

  16. CO2 laser therapy of rhinophyma

    Science.gov (United States)

    Voigt, Peggy; Jovanovic, Sergije; Sedlmaier, Benedikt W.

    2000-06-01

    Laser treatment of skin changes has become common practice in recent years. High absorption of the CO2 laser wavelength in water is responsible for its low penetration dpt in biological tissue. Shortening the tissue exposure time minimizes thermic side effects of laser radiation such as carbonization and coagulation. This can be achieved with scanner systems that move the focused laser beam over a defined area by microprocessor-controlled rapidly rotating mirrors. This enables controlled and reliable removal of certain dermal lesions, particularly hypertrophic scar/span>s, scars after common acne, wrinkles and rhinophyma. Laser ablation of rhinophyma is a stress-minimizing procedure for the surgeon and the patient, since it is nearly bloodless and can be performed under local anaesthesia. Cosmetically favorable reepithelization of the lasered surfaces is achieved within a very short period of time.

  17. Smart Transportation CO2 Emission Reduction Strategies

    Science.gov (United States)

    Tarulescu, S.; Tarulescu, R.; Soica, A.; Leahu, C. I.

    2017-10-01

    Transport represents the sector with the fastest growing greenhouse gas emissions around the world. The main global objective is to reduce energy usage and associated greenhouse gas emissions from the transportation sector. For this study it was analyzed the road transportation system from Brasov Metropolitan area. The study was made for the transportation route that connects Ghimbav city to the main surrounding objectives. In this study ware considered four optimization measures: vehicle fleet renewal; building the detour belt for the city; road increasing the average travel speed; making bicycle lanes; and implementing an urban public transport system for Ghimbav. For each measure it was used a mathematical model to calculate the energy consumption and carbon emissions from the road transportation sector. After all four measures was analyzed is calculated the general energy consumption and CO2 reduction if this are applied from year 2017 to 2020.

  18. Enhanced Molecular Sieve CO2 Removal Evaluation

    Science.gov (United States)

    Rose, Susan; ElSherif, Dina; MacKnight, Allen

    1996-01-01

    The objective of this research is to quantitatively characterize the performance of two major types of molecular sieves for two-bed regenerative carbon dioxide removal at the conditions compatible with both a spacesuit and station application. One sorbent is a zeolite-based molecular sieve that has been substantially improved over the materials used in Skylab. The second sorbent is a recently developed carbon-based molecular sieve. Both molecular sieves offer the potential of high payoff for future manned missions by reducing system complexity, weight (including consumables), and power consumption in comparison with competing concepts. The research reported here provides the technical data required to improve CO2 removal systems for regenerative life support systems for future IVA and EVA missions.

  19. Phase Locking of CO(2) Lasers.

    Science.gov (United States)

    Weingartner, W; Schröder, K; Schuöcker, D

    2001-05-20

    A method of phase locking two CO(2) lasers by radiation exchange is presented. This phase-locking was achieved by use of a copper prism as a beam folding device in the resonators and extraction of the output radiation by a common output coupler. Energy exchange led to a phase-locked state if several locking conditions were fulfilled. The amount of radiation injected from one resonator to the second cavity could be adjusted by movement of the prism. The influence of the strength of coupling on the locking range was studied. The beat signal between the two unlocked lasers could be measured, whereas in the case of phase-locked operation twice the intensity was detected. Despite the inclusion of several assumptions, a simplified mathematical model delivered good agreement between calculated and experimental results.

  20. Experimental Investigations into CO2 Interactions with Injection Well Infrastructure for CO2 Storage

    Science.gov (United States)

    Syed, Amer; Shi, Ji-Quan; Durucan, Sevket; Nash, Graham; Korre, Anna

    2013-04-01

    Wellbore integrity is an essential requirement to ensure the success of a CO2 Storage project as leakage of CO2 from the injection or any other abandoned well in the storage complex, could not only severely impede the efficiency of CO2 injection and storage but also may result in potential adverse impact on the surrounding environment. Early research has revealed that in case of improper well completions and/or significant changes in operating bottomhole pressure and temperature could lead to the creation of microannulus at cement-casing interface which may constitute a preferential pathway for potential CO2 leakage during and post injection period. As a part of a European Commission funded CO2CARE project, the current research investigates the sealing behaviour of such microannulus at the cement-casing interface under simulated subsurface reservoir pressure and temperature conditions and uses the findings to develop a methodology to assess the overall integrity of CO2 storage. A full scale wellbore experimental test set up was constructed for use under elevated pressure and temperature conditions as encountered in typical CO2 storage sites. The wellbore cell consists of an assembly of concentric elements of full scale casing (Diameter= 0.1524m), cement sheath and an outer casing. The stainless steel outer ring is intended to simulate the stiffness offered by the reservoir rock to the displacement applied at the wellbore. The Central Loading Mechanism (CLM) consists of four case hardened shoes that can impart radial load onto the well casing. The radial movement of the shoes is powered through the synchronised movement of four precision jacks controlled hydraulically which could impart radial pressures up to 15 MPa. The cell body is a gas tight enclosure that houses the wellbore and the central loading mechanism. The setup is enclosed in a laboratory oven which acts both as temperature and safety enclosure. Prior to a test, cement mix is set between the casing and

  1. Enhanced transport phenomena in CO2 sequestration and CO2 EOR

    NARCIS (Netherlands)

    Farajzadeh, R.

    2009-01-01

    The results of this thesis give insight into the (mass)-transfer during flow of gases, especially CO2, in various gas-liquid systems. A number of experiments was performed to investigate the transport phenomena through interfaces with and without surfactant monolayers. The observed phenomena have

  2. Root-derived CO2 efflux via xylem stream rivals soil CO2 efflux

    Science.gov (United States)

    Doug P. Aubrey; Robert O. Teskey

    2009-01-01

    Respiration consumes a large portion of annual gross primary productivity in forest ecosystems and is dominated by belowground metabolism. Here, we present evidence of a previously unaccounted for internal CO2 flux of large magnitude from tree roots through stems. If this pattern is shown to persist over time and in other forests, it suggests...

  3. DEPLETED HYDROCARBON RESERVOIRS AND CO2 INJECTION WELLS –CO2 LEAKAGE ASSESSMENT

    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec

    2017-03-01

    Full Text Available Migration risk assessment of the injected CO2 is one of the fi rst and indispensable steps in determining locations for the implementation of projects for carbon dioxide permanent disposal in depleted hydrocarbon reservoirs. Within the phase of potential storage characterization and assessment, it is necessary to conduct a quantitative risk assessment, based on dynamic reservoir models that predict the behaviour of the injected CO2, which requires good knowledge of the reservoir conditions. A preliminary risk assessment proposed in this paper can be used to identify risks of CO2 leakage from the injection zone and through wells by quantifying hazard probability (likelihood and severity, in order to establish a risk-mitigation plan and to engage prevention programs. Here, the proposed risk assessment for the injection well is based on a quantitative risk matrix. The proposed assessment for the injection zone is based on methodology used to determine a reservoir probability in exploration and development of oil and gas (Probability of Success, abbr. POS, and modifi ed by taking into account hazards that may lead to CO2 leakage through the cap rock in the atmosphere or groundwater. Such an assessment can eliminate locations that do not meet the basic criteria in regard to short-term and long-term safety and the integrity of the site

  4. CO2-ECBM and CO2 Sequestration in Polish Coal Seam – Experimental Study

    Directory of Open Access Journals (Sweden)

    Paweł Baran

    2014-01-01

    Originality/value: The results indicate successful sorption of carbon dioxide in each experiment. This provides the rationale to study the application of the coal tested to obtain methane genetic origin genetic methane with the use of the CO2 injection.

  5. Novel Long-Term CO2 Removal System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Current Technology for CO2 removal from enclosed air of spacecraft utilizes LiOH canisters for CO2 absorption. This absorption is irreversible so longer flights...

  6. Framework for Assessing Biogenic CO2 Emissions from Stationary Sources

    Science.gov (United States)

    This revision of the 2011 report, Accounting Framework for Biogenic CO2 Emissions from Stationary Sources, evaluates biogenic CO2 emissions from stationary sources, including a detailed study of the scientific and technical issues associated with assessing biogenic carbon dioxide...

  7. Comparison of regional and ecosystem CO2 fluxes

    DEFF Research Database (Denmark)

    Gryning, Sven-Erik; Søgaard, Henrik; Batchvarova, Ekaterina

    2009-01-01

    A budget method to derive the regional surface flux of CO2 from the evolution of the boundary layer is presented and applied. The necessary input for the method can be deduced from a combination of vertical profile measurements of CO2 concentrations by i.e. an airplane, successive radio......-soundings and standard measurements of the CO2 concentration near the ground. The method was used to derive the regional flux of CO2 over an agricultural site at Zealand in Denmark during an experiment on 12–13 June 2006. The regional fluxes of CO2 represent a combination of agricultural and forest surface conditions....... It was found that the regional flux of CO2 in broad terms follows the behavior of the flux of CO2 at the agricultural (grassland) and the deciduous forest station. The regional flux is comparable not only in size but also in the diurnal (daytime) cycle of CO2 fluxes at the two stations....

  8. Non-CO2 Greenhouse Gases: International Emissions and Projections

    Science.gov (United States)

    EPA August 2011 report on global non-CO2 emissions projections (1990-2030) for emissions of non-CO2 greenhouse gases (methane, nitrous oxide, and fluorinated greenhouse gases) from more than twenty emissions sources.

  9. Understanding and predicting trends in north Atlantic CO2 uptake

    Science.gov (United States)

    Halloran, Paul; Lebehot, Alice; Watson, Andy; McNeall, Doug; Ford, David; Schuster, Ute

    2017-04-01

    To determine the maximum carbon dioxide (CO2) emissions society must commit to, to remain below a given atmospheric CO2 threshold, the scientific community must robustly quantify what proportion of human emitted CO2 will be taken up by the land and marine carbon reservoirs. The North Atlantic Ocean is the most intense marine sink of anthropogenic CO2 on the planet, accounting for about a fifth of the global oceanic anthropogenic CO2 uptake, despite covering just 15% of the global ocean area. Carefully assessing uncertainties, we quantify the real-world trend in North Atlantic CO2 uptake over the past two decades. Comparing this to results from state-of-the-art climate models, we find that models are systematically underestimating the observed CO2 uptake trend. By performing a set of targeted climate model simulations, we diagnose and account for this bias, and produce the first set of observation-informed future ocean CO2 uptake predictions.

  10. Chemical reduction of CO2 facilitated by C-nucleophiles.

    Science.gov (United States)

    Janes, Trevor; Yang, Yanxin; Song, Datong

    2017-10-17

    The abundance of atmospheric CO2 presents both an opportunity and a challenge for synthetic chemists to transform CO2 into value-added products. A promising strategy involves CO2 reduction driven by the energy stored in chemical bonds and promoted by molecules containing nucleophilic carbon sites. This approach allows the synthesis of new C-C or C-H bonds from CO2-derived carbon. The first part of this Feature article deals with uncatalyzed reductions of CO2 such as insertion into metal-carbon bonds and reactivity towards multidentate actor ligands and metal-free compounds. The second part covers catalytic reduction of CO2 in which a nucleophilic C-site is involved. This review brings together two general approaches in the chemical CO2 reduction field, showing how the discovery of fundamental reactivity of CO2 leads to synthetic applications, and proposes directions for further development.

  11. Concentration-dependent diffusion instability in reactive miscible fluids.

    Science.gov (United States)

    Bratsun, Dmitry; Kostarev, Konstantin; Mizev, Aleksey; Mosheva, Elena

    2015-07-01

    We report on chemoconvective pattern formation phenomena observed in a two-layer system of miscible fluids filling a vertical Hele-Shaw cell. We show both experimentally and theoretically that the concentration-dependent diffusion coupled with frontal acid-base neutralization can give rise to the formation of a local unstable zone low in density, resulting in a perfectly regular cell-type convective pattern. The described effect gives an example of yet another powerful mechanism which allows the reaction-diffusion processes to govern the flow of reacting fluids under gravity conditions.

  12. Miscibility Phase Diagrams of Giant Vesicles Containing Sphingomyelin

    Science.gov (United States)

    Veatch, Sarah L.; Keller, Sarah L.

    2005-04-01

    Saturated sphingomyelin (SM) lipids are implicated in lipid rafts in cell plasma membranes. Here we use fluorescence microscopy to observe coexisting liquid domains in vesicles containing SM, an unsaturated phosphatidylcholine lipid (either DOPC or POPC), and cholesterol. We note similar phase behavior in a model membrane mixture without SM (DOPC/DPPC/Chol), but find no micron-scale liquid domains in membranes of POPC/PSM/Chol. We delineate the onset of solid phases below the miscibility transition temperature, and detail indirect evidence for a three-phase coexistence of one solid and two liquid phases.

  13. Theory of Interfacial Tension of Partially Miscible Liquids

    OpenAIRE

    Boudh-Hir, M. -E.; Mansoori, G. A.

    2017-01-01

    The aim of this work is to study the problem of the existence of a fundamental relation between the interfacial tension of a system of two partially miscible liquids and the surface tensions of the pure substances. It is shown that these properties cannot be correlated from the physical point of view. However, an accurate relation between them may be developed using a mathematical artifact. In the light of this work, the basis of the empirical formula of Girifalco and Good is examined. The we...

  14. Calculation of minimum miscibility pressure using fast slimtube simulation

    DEFF Research Database (Denmark)

    Yan, Wei; Michelsen, Michael Locht; Stenby, Erling Halfdan

    2012-01-01

    Minimum misciblility pressure (MMP) is a critical parameter in designing a miscible gas injection process. It is expected that 100% displacement efficiency on the microscopic scale can be achieved provided the injection pressure is above MMP. Two approaches are usually employed for equation of st...... is poroposed to reduce the number of slimtube simulations needed. In addition, it is also discussed how to parallelize slimtube simulations for modem computers with multiple CPU cores to further chop the computation time. Copyright 2012, Society of Petroleum Engineers....

  15. Atmospheric measurement of point source fossil fuel CO2 emissions

    Science.gov (United States)

    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.

  16. Can elevated CO(2) improve salt tolerance in olive trees?

    Science.gov (United States)

    Melgar, Juan Carlos; Syvertsen, James P; García-Sánchez, Francisco

    2008-04-18

    We compared growth, leaf gas exchange characteristics, water relations, chlorophyll fluorescence, and Na(+) and Cl(-) concentration of two cultivars ('Koroneiki' and 'Picual') of olive (Olea europaea L.) trees in response to high salinity (NaCl 100mM) and elevated CO(2) (eCO(2)) concentration (700microLL(-1)). The cultivar 'Koroneiki' is considered to be more salt sensitive than the relatively salt-tolerant 'Picual'. After 3 months of treatment, the 9-month-old cuttings of 'Koroneiki' had significantly greater shoot growth, and net CO(2) assimilation (A(CO(2))) at eCO(2) than at ambient CO(2), but this difference disappeared under salt stress. Growth and A(CO(2)) of 'Picual' did not respond to eCO(2) regardless of salinity treatment. Stomatal conductance (g(s)) and leaf transpiration were decreased at eCO(2) such that leaf water use efficiency (WUE) increased in both cultivars regardless of saline treatment. Salt stress increased leaf Na(+) and Cl(-) concentration, reduced growth and leaf osmotic potential, but increased leaf turgor compared with non-salinized control plants of both cultivars. Salinity decreased A(CO(2)), g(s), and WUE, but internal CO(2) concentrations in the mesophyll were not affected. eCO(2) increased the sensitivity of PSII and chlorophyll concentration to salinity. eCO(2) did not affect leaf or root Na(+) or Cl(-) concentrations in salt-tolerant 'Picual', but eCO(2) decreased leaf and root Na(+) concentration and root Cl(-) concentration in the more salt-sensitive 'Koroneiki'. Na(+) and Cl(-) accumulation was associated with the lower water use in 'Koroneiki' but not in 'Picual'. Although eCO(2) increased WUE in salinized leaves and decreased salt ion uptake in the relatively salt-tolerant 'Koroneiki', growth of these young olive trees was not affected by eCO(2).

  17. [Effects of plastic film mulching on soil CO2 efflux and CO2 concentration in an oasis cotton field].

    Science.gov (United States)

    Yu, Yong-xiang; Zhao, Cheng-yi; Jia, Hong-tao; Yu, Bo; Zhou, Tian-he; Yang, Yu-guang; Zhao, Hua

    2015-01-01

    A field study was conducted to compare soil CO2 efflux and CO2 concentration between mulched and non-mulched cotton fields by using closed chamber method and diffusion chamber technique. Soil CO2 efflux and CO2 concentration exhibited a similar seasonal pattern, decreasing from July to October. Mulched field had a lower soil CO2 efflux but a higher CO2 concentration, compared to those of non-mulched fields. Over the measurement period, cumulative CO2 efflux was 1871.95 kg C . hm-2 for mulched field and 2032.81 kg C . hm-2 for non-mulched field. Soil CO2 concentration was higher in mulched field (ranging from 5137 to 25945 µL . L-1) than in non- mulched field (ranging from 2165 to 23986 µL . L-1). The correlation coefficients between soil CO2 concentrations at different depths and soil CO2 effluxes were 0.60 to 0.73 and 0.57 to 0.75 for the mulched and non-mulched fields, indicating that soil CO2 concentration played a crucial role in soil CO2 emission. The Q10 values were 2.77 and 2.48 for the mulched and non-mulched fields, respectively, suggesting that CO2 efflux in mulched field was more sensitive to the temperature.

  18. Estimation of CE–CVM energy parameters from miscibility gap data

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 28; Issue 2. Estimation of CE–CVM energy parameters from miscibility gap data. G Srinivasa Gupta G ... As a starting point, a method has been devised to estimate the values of energy parameters from consolute point (miscibility gap maximum) data. Empirical relations ...

  19. CO2 (dry ice) cleaning system

    Science.gov (United States)

    Barnett, Donald M.

    1995-03-01

    Tomco Equipment Company has participated in the dry ice (solid carbon dioxide, CO2) cleaning industry for over ten years as a pioneer in the manufacturer of high density, dry ice cleaning pellet production equipment. For over four years Tomco high density pelletizers have been available to the dry ice cleaning industry. Approximately one year ago Tomco introduced the DI-250, a new dry ice blast unit making Tomco a single source supplier for sublimable media, particle blast, cleaning systems. This new blast unit is an all pneumatic, single discharge hose device. It meters the insertion of 1/8 inch diameter (or smaller), high density, dry ice pellets into a high pressure, propellant gas stream. The dry ice and propellant streams are controlled and mixed from the blast cabinet. From there the mixture is transported to the nozzle where the pellets are accelerated to an appropriate blasting velocity. When directed to impact upon a target area, these dry ice pellets have sufficient energy to effectively remove most surface coatings through dry, abrasive contact. The meta-stable, dry ice pellets used for CO2 cleaning, while labeled 'high density,' are less dense than alternate, abrasive, particle blast media. In addition, after contacting the target surface, they return to their equilibrium condition: a superheated gas state. Most currently used grit blasting media are silicon dioxide based, which possess a sharp tetrahedral molecular structure. Silicon dioxide crystal structures will always produce smaller sharp-edged replicas of the original crystal upon fracture. Larger, softer dry ice pellets do not share the same sharp-edged crystalline structures as their non-sublimable counterparts when broken. In fact, upon contact with the target surface, dry ice pellets will plastically deform and break apart. As such, dry ice cleaning is less harmful to sensitive substrates, workers and the environment than chemical or abrasive cleaning systems. Dry ice cleaning system

  20. A liquid CO2-compatible hydrocarbon surfactant: experiment and modelling

    NARCIS (Netherlands)

    Banerjee, S.; Kleijn, J.M.; Cohen Stuart, M.A.; Leermakers, F.A.M.

    2013-01-01

    Surfactants soluble in liquid CO2 are rare and knowledge on interfacial and self-assembly behaviour is fragmented. We found that polyoxyethylene (5) isooctylphenyl ether is interfacially active at the water–liquid CO2 interface. Water–liquid CO2 interfacial tension was measured at various surfactant

  1. Activation of CO2 by phosphinoamide hafnium complexes.

    Science.gov (United States)

    Sgro, Michael J; Stephan, Douglas W

    2013-04-04

    Hf-phosphinoamide cation complexes behave as metal-based frustrated Lewis pairs and bind one or two equivalent of CO2 and in as well can activate CO2 in a bimetallic fashion to give a pseudo-tetrahedral P2CO2 fragment linking two Hf centres.

  2. CO2-laserchirurgie van leukoplakie van het mondslijmvlies

    NARCIS (Netherlands)

    Roodenburg, Johannes Leendert Nicolaas

    1985-01-01

    The purpose of this investigation is: 1. to gain an insight into the direct effect of CO2-laserlight on oral mucosa; 2. to study the healing of oral mucosa after being damaged by CO2-laserlight; 3. to evaluate the CO2-laserevaporataion as a treatment modality for oral leukoplakia. ... Zie: Summary

  3. Impacts: economic trade-offs for CO2 impurity specification

    NARCIS (Netherlands)

    Eickhoff, C.; Neele, F.P.; Hammer, M.; DiBiagio, M.; Hofstee, C.; Koenen, M.; Fischer, S.; Isaenko, A.; Brown, A.; Kovacs, T.

    2014-01-01

    The IMPACTS project has a stated broad objective to develop the knowledge base of CO2 quality required for establishing norms and regulations to ensure safe and reliable design, construction and operation of CO2 pipelines and injection equipment, and safe long-term geological storage of CO2. More

  4. Thermogravimetric and model-free kinetic studies on CO2 ...

    Indian Academy of Sciences (India)

    Coal gasification with CO 2 has emerged as a cleaner and more efficient way for the production of energy, and it offers the advantages of CO 2 mitigation policies through simultaneous CO 2 sequestration. In the present investigation, a feasibility study on the gasification of three low-quality, high-sulphur coals fromthe ...

  5. Ventilation in Sewers Quantified by Measurements of CO2

    DEFF Research Database (Denmark)

    Fuglsang, Emil Dietz; Vollertsen, Jes; Nielsen, Asbjørn Haaning

    2012-01-01

    H, alkalinity and sewer-air CO2 concentrations. An intercepting sewer was studied and an average sewer-air retention time of approximately 1.5-2.5 hours was found at CO2 levels around 4-6 times the natural background. Also an upstream sub-catchment was studied. In this part of the sewer system the level of CO2...

  6. Designing an oscillating CO2 concentration experiment for field chambers

    Science.gov (United States)

    Questions have arisen about photosynthetic response to fluctuating carbon dioxide (CO2), which might affect yield in free-air CO2 enrichment (FACE) systems and in open top chambers. A few studies have been conducted based on CO2 controlled to cycles of fixed time-periods and fixed, large amplitude....

  7. Designing an oscillating CO2 concentration experiment for fild chambers

    Science.gov (United States)

    Questions have arisen about photosynthetic response to fluctuating carbon dioxide (CO2), which might affect yield in free-air CO2 enrichment (FACE) systems and in open top chambers. A few studies have been conducted based on CO2 controlled to cycles of fixed time-periods and fixed, large amplitude....

  8. End tidal CO2 versus arterial CO2 monitoring in patients undergoing coronary artery bypass graft

    Directory of Open Access Journals (Sweden)

    Hassani E

    2009-12-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Measuring end tidal carbon dioxide (ETCo2 is one of the methods used for estimating arterial carbon dioxide (PaCo2 during general anesthesia. ETCo2 measurements maybe obviate the need for repeating arterial puncture for determination of arterial PaCo2. This study performed to determine the accuracy of ETCo2 levels as a measure of PaCo2 levels in patients undergoing coronary artery bypass graft and also to evaluate variation of the gradient between PaCo2 and ETCo2, peri- cardiopulmonary bypass operation."n"nMethods: In a prospective, cross-sectional study, a total of 40 patients with age 57±11 (35-73 years old undergoing coronary artery bypass graft were enrolled. ETCo2 levels (mmHg were recorded using side stream capnography at the time of arterial blood gas sampling, before (T0 and after (T1 cardiopulmonary bypass."n"nResults: Mean P(a-ETCo2 at T0 was 4.3±4.4mmHg, with the mean PaCo2, 33±6mmHg and mean ETCo2, 29±5mmHg and these values at T1 were 4.5±4.1mmHg, 33±5mmHg and 29±2mmHg respectively. There was no variation of the mean gradient (PaCo2-PETCo2 during, before and after cardiopulmonary bypass (p>0.870. Significant correlation was found between ETCo2 and PaCo2 at T0 and T1 (r=0.754 and 0

  9. Sensory Transduction of the CO2 Response of Guard Cells

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Eduardo Zeiger

    2003-06-30

    Stomata have a key role in the regulation of gas exchange and intercellular CO2 concentrations of leaves. Guard cells sense internal and external signals in the leaf environment and transduce these signals into osmoregulatory processes that control stomatal apertures. This research proposal addresses the characterization of the sensory transduction of the CO2 signal in guard cells. Recent studies have shown that in Vicia leaves kept at constant light and temperature in a growth chamber, changes in ambient CO2 concentrations cause large changes in guard cell zeaxanthin that are linear with CO2-dependent changes in stomatal apertures. Research proposed here will test the hypothesis that zeaxanthin function as a transducer of CO2 signals in guard cells. Three central aspects of this hypothesis will be investigated: CO2 sensing by the carboxylation reaction of Rubisco in the guard cell chloroplast, which would modulate zeaxanthin concentrations via changes in lumen pH; transduction of the CO2 signal by zeaxanthin via a transducing cascade that controls guard cell osmoregulation; and blue light dependence of the CO2 signal transduction by zeaxanthin, required for the formation of an isomeric form of zeaxanthin that is physiologically active as a transducer. The role of Rubisco in CO2 sensing will be investigated in experiments characterizing the stomatal response to CO2 in the Arabidopsis mutants R100 and rca-, which have reduced rates of Rubisco-dependent carboxylation. The role of zeaxanthin as a CO2 transducer will be studied in npq1, a zeaxanthin-less mutant. The blue light-dependence of CO2 sensing will be studied in experiments characterizing the stomatal response to CO2 under red light. Arabidopsis mutants will also be used in further studies of an acclimation of the stomatal response to CO2, and a possible role of the xanthophyll cycle of the guard cell chloroplast in acclimations of the stomatal response to CO2. Studies on the osmoregulatory role of sucrose in

  10. CO2 Condensation Models for Mars

    Science.gov (United States)

    Colaprete, A.; Haberle, R.

    2004-01-01

    During the polar night in both hemispheres of Mars, regions of low thermal emission, frequently referred to as "cold spots", have been observed by Mariner 9, Viking and Mars Global Surveyor (MGS) spacecraft. These cold spots vary in time and appear to be associated with topographic features suggesting that they are the result of a spectral-emission effect due to surface accumulation of fine-grained frost or snow. Presented here are simulations of the Martian polar night using the NASA Ames General Circulation Cloud Model. This cloud model incorporates all the microphysical processes of carbon dioxide cloud formation, including nucleation, condensation and sedimentation and is coupled to a surface frost scheme that includes both direct surface condensation and precipitation. Using this cloud model we simulate the Mars polar nights and compare model results to observations from the Thermal Emission Spectrometer (TES) and the Mars Orbiter Laser Altimeter (MOLA). Model predictions of "cold spots" compare well with TES observations of low emissivity regions, both spatially and as a function of season. The model predicted frequency of CO2 cloud formation also agrees well with MOLA observations of polar night cloud echoes. Together the simulations and observations in the North indicate a distinct shift in atmospheric state centered about Ls 270 which we believe may be associated with the strength of the polar vortex.

  11. Removing extra CO2 in COPD patients.

    Science.gov (United States)

    Lund, Laura W; Federspiel, William J

    2013-01-01

    For patients experiencing acute respiratory failure due to a severe exacerbation of chronic obstructive pulmonary disease (COPD), noninvasive positive pressure ventilation has been shown to significantly reduce mortality and hospital length of stay compared to respiratory support with invasive mechanical ventilation. Despite continued improvements in the administration of noninvasive ventilation (NIV), refractory hypercapnia and hypercapnic acidosis continue to prevent its successful use in many patients. Recent advances in extracorporeal gas exchange technology have led to the development of systems designed to be safer and simpler by focusing on the clinical benefits of partial extracorporeal carbon dioxide removal (ECCO2R), as opposed to full cardiopulmonary support. While the use of ECCO2R has been studied in the treatment of acute respiratory distress syndrome (ARDS), its use for acute hypercapnic respiratory during COPD exacerbations has not been evaluated until recently. This review will focus on literature published over the last year on the use of ECCO2R for removing extra CO2 in patients experiencing an acute exacerbation of COPD.

  12. Study of hydrocarbon miscible solvent slug injection process for improved recovery of heavy oil from Schrader Bluff Pool, Milne Point Unit, Alaska. Annual report, December 1, 1992--December 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, G.D.

    1994-01-01

    The shallow Cretaceous sands of the Schrader Bluff Reservoir occur between depths of 4,000 and 4,800 feet below surface and are estimated to contain up to 1.5 billion barrels of oil in place. The field is currently under production by primary depletion. Initial production indicated that primary recovery will fall short of earlier estimates and waterflooding will have to be employed much earlier than expected. A large portion of the oil-in-place thus would still be left behind in this reservoir after primary and secondary recovery methods have been applied. Enhanced oil recovery (EOR) techniques will be needed to recover the additional portion of remaining oil in this huge reservoir and to add significant additional reserves. Slim tube displacement studies, PVT data and asphaltene precipitation studies are needed for Schrader Bluff heavy oil to define possible hydrocarbon solvent suitable for miscible solvent slug displacement process. Such studies are essential because the API gravity of the crude in Schrader Bluff reservoir varies significantly from well to well. Coreflood experiments are also needed to determine effect of solvent slug size, WAG ratio and solvent composition on the oil recovery and solvent breakthrough. A compositional reservoir simulation study will be conducted later to evaluate the complete performance of the hydrocarbon solvent slug process and to assess the feasibility of this process for improving recovery of heavy oil from Schrader Bluff reservoir. This report contains the following: reservoir description; slim tube displacement studies; and coreflood experiments.

  13. Thermodynamic Properties of CO2 Mixtures and Their Applications in Advanced Power Cycles with CO2 Capture Processes

    OpenAIRE

    Li, Hailong

    2008-01-01

    The thermodynamic properties of CO2-mixtures are essential for the design and operation of CO2 Capture and Storage (CCS) systems. A better understanding of the thermodynamic properties of CO2 mixtures could provide a scientific basis to define a proper guideline of CO2 purity and impure components for the CCS processes according to technical, safety and environmental requirements. However the available accurate experimental data cannot cover the whole operation conditions of CCS processes. In...

  14. Greenhouse gas capture. Norwegian test facility for CO2-technology; Broeikasgasvangers. Noors testcentrum voor CO2-technologie

    Energy Technology Data Exchange (ETDEWEB)

    Van Velzen, T.

    2012-02-03

    In Norway a large research center on the capture of CO2 will be opened in the spring of 2012: the CO2 Technology Centre Mongstad. It allows companies to test concepts for CCS (carbon dioxide capture and storage) [Dutch] In Noorwegen wordt in de lente van 2012 een groot centrum voor onderzoek naar het afvangen van CO2 geopend: het CO2 Technology Centre Mongstad. Daar kunnen bedrijven hun concepten voor CCS beproeven.

  15. Dual-slug miscible displacement of Bradford crude. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, C.D.

    1965-07-01

    An examination of the results presented in graphs showing (1) effect of buffer slug viscosity on isopropyl alcohol-free oleic phase recovery, and (2) viscosity ratio (Bradford crude/buffer slug), indicate that phase behavior was a more critical parameter than viscosity ratio in determining the recovery efficiency of the buffer slug for the systems studied. Solvent-free oleic phase recovery increased 2.6 times as the viscosity ratio was increased from 0.8 to 36. Pure oil recovery was greatest for the most adverse viscosity ratio. Of all the buffer materials tested, propane gave a higher pure oil recovery than an amyl alcohol for a viscosity ratio of 1.09. It should be emphasized that in the combination slug process one is concerned with two aspects of phase behavior. First, the in-place oil is miscibly displaced by the buffer slug which is usually immiscible with the brine in the core. Then, on the injection of isopropyl alcohol, a completely miscible process occurs at the rear of the buffer fluid, as the brine-drive alcohol removes all of the remaining reservoir fluids under ideal conditions. The ternary diagrams illustrated provide an indication only to the mechanism of the latter process.

  16. CO2 niet meer dan genoeg: Teelt van Tomaat in 2012 bij Improvement Centre met lichtafhankelijk doseren van CO2

    NARCIS (Netherlands)

    Gelder, de A.; Warmenhoven, M.G.; Dieleman, J.A.; Klapwijk, P.; Baar, van P.H.

    2014-01-01

    Wageningen UR Glastuinbouw heeft met financiering van Kas als Energiebron en Samenwerken aan Vaardigheden onderzoek gedaan naar efficienter gebruik van CO2. In een kasproef bij GreenQ/Improvement Centre is een CO2 doseerstrategie getest, waarbij iets meer CO2 wordt gegeven dan er op basis van de

  17. Detection of CO2 leaks from carbon capture and storage sites with combined atmospheric CO2 and O-2 measurements

    NARCIS (Netherlands)

    van Leeuwen, Charlotte; Meijer, Harro A. J.

    2015-01-01

    This paper presents a transportable instrument that simultaneously measures the CO2 and (relative) O-2 concentration of the atmosphere with the purpose to aid in the detection of CO2 leaks from CCS sites. CO2 and O-2 are coupled in most processes on earth (e.g., photosynthesis, respiration and

  18. The effects of CO2-differentiated vehicle tax systems on car choice, CO2 emissions and tax revenues

    NARCIS (Netherlands)

    Kok, R.

    2011-01-01

    This paper assesses the impacts of a CO2-differentiated tax policy designed to influence car purchasing trends towards lower CO2 emitting vehicles in the Netherlands. Since 2009, gasoline and diesel cars up to 110 and 95 gram CO2 per km are exempted from the vehicle registration tax (VRT). In

  19. Application of ammonia and CO2 in supermarkets; Toepassing van ammoniak en CO2 in supermarkten

    Energy Technology Data Exchange (ETDEWEB)

    Stoecker, W.F.; Hrnjak, P.J. [University of Illinois, Urbana-Champaign, IL (United States); Infante Ferreiria, C.A. [Technische Universiteit Delft, Delft (Netherlands)

    2001-08-01

    The application of microchannel condensers in ammonia installations makes it possible to go down as far as 18 g NH3 per kW refrigeration. The use of ammonia in combination with CO2 contributes to economic effective and energy efficient solutions for supermarket applications. In this article also the experiences in Sweden, Denmark and Italy with indirect, cascade and transcritical supermarket refrigeration systems with carbon dioxide are described. 8 refs.

  20. Recent global CO2 flux inferred from atmospheric CO2 observations and its regional analyses

    Directory of Open Access Journals (Sweden)

    J. M. Chen

    2011-11-01

    Full Text Available The net surface exchange of CO2 for the years 2002–2007 is inferred from 12 181 atmospheric CO2 concentration data with a time-dependent Bayesian synthesis inversion scheme. Monthly CO2 fluxes are optimized for 30 regions of the North America and 20 regions for the rest of the globe. Although there have been many previous multiyear inversion studies, the reliability of atmospheric inversion techniques has not yet been systematically evaluated for quantifying regional interannual variability in the carbon cycle. In this study, the global interannual variability of the CO2 flux is found to be dominated by terrestrial ecosystems, particularly by tropical land, and the variations of regional terrestrial carbon fluxes are closely related to climate variations. These interannual variations are mostly caused by abnormal meteorological conditions in a few months in the year or part of a growing season and cannot be well represented using annual means, suggesting that we should pay attention to finer temporal climate variations in ecosystem modeling. We find that, excluding fossil fuel and biomass burning emissions, terrestrial ecosystems and oceans absorb an average of 3.63 ± 0.49 and 1.94 ± 0.41 Pg C yr−1, respectively. The terrestrial uptake is mainly in northern land while the tropical and southern lands contribute 0.62 ± 0.47, and 0.67 ± 0.34 Pg C yr−1 to the sink, respectively. In North America, terrestrial ecosystems absorb 0.89 ± 0.18 Pg C yr−1 on average with a strong flux density found in the south-east of the continent.

  1. The Influence of CO2 Solubility in Brine on Simulation of CO2 Injection into Water Flooded Reservoir and CO2 WAG

    DEFF Research Database (Denmark)

    Yan, Wei; Stenby, Erling Halfdan

    2010-01-01

    simulations. In our previous study, a 1-D slimtube simulator, which rigorously accounts for both CO2 solubility in brine and water content in hydrocarbon phases using the Peng-Robinson EoS modified by Soreide and Whitson, has been used to investigate the influence of CO2 solubility on the simulation...

  2. Sequestering CO2 in the Built Environment

    Science.gov (United States)

    Constantz, B. R.

    2009-12-01

    Calera’s Carbonate Mineralization by Aqueous Precipitation (CMAP) technology with beneficial reuse has been called, “game-changing” by Carl Pope, Director of the Sierra Club. Calera offers a solution to the scale of the carbon problem. By capturing carbon into the built environment through carbonate mineralization, Calera provides a sound and cost-effective alternative to Geologic Sequestration and Terrestrial Sequestration. The CMAP technology permanently converts carbon dioxide into a mineral form that can be stored above ground, or used as a building material. The process produces a suite of carbonate-containing minerals of various polymorphic forms. Calera product can be substituted into blends with ordinary Portland cements and used as aggregate to produce concrete with reduced carbon, carbon neutral, or carbon negative footprints. For each ton of product produced, approximately half a ton of carbon dioxide can be sequestered using the Calera process. Coal and natural gas are composed of predominately istopically light carbon, as the carbon in the fuel is plant-derived. Thus, power plant CO2 emissions have relatively low δ13C values.The carbon species throughout the CMAP process are identified through measuring the inorganic carbon content, δ13C values of the dissolved carbonate species, and the product carbonate minerals. Measuring δ13C allows for tracking the flue gas CO2 throughout the capture process. Initial analysis of the capture of propane flue gas (δ13C ˜ -25 ‰) with seawater (δ13C ˜ -10 ‰) and industrial brucite tailings from a retired magnesium oxide plant in Moss Landing, CA (δ13C ˜ -7 ‰ from residual calcite) produced carbonate mineral products with a δ13C value of ˜ -20 ‰. This isotopically light carbon, transformed from flue gas to stable carbonate minerals, can be transferred and tracked through the capture process, and finally to the built environment. CMAP provides an economical solution to global warming by producing

  3. 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

    Science.gov (United States)

    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

  4. Atmospheric measurement of point source fossil CO2 emissions

    Science.gov (United States)

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

    2014-05-01

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

  5. Use of sediment CO2 by submersed rooted plants.

    Science.gov (United States)

    Winkel, Anders; Borum, Jens

    2009-05-01

    Submersed plants have different strategies to overcome inorganic carbon limitation. It is generally assumed that only small rosette species (isoetids) are able to utilize the high sediment CO(2) availability. The present study examined to what extent five species of submersed freshwater plants with different morphology and growth characteristics (Lobelia dortmanna, Lilaeopsis macloviana, Ludwigia repens, Vallisneria americana and Hydrocotyle verticillata) are able to support photosynthesis supplied by uptake of CO(2) from the sediment. Gross photosynthesis was measured in two-compartment split chambers with low inorganic carbon availability in leaf compartments and variable CO(2) availability (0 to >8 mmol L(-1)) in root compartments. Photosynthetic rates based on root-supplied CO(2) were compared with maximum rates obtained at saturating leaf CO(2) availability, and (14)C experiments were conducted for two species to localize bottlenecks for utilization of sediment CO(2). All species except Hydrocotyle were able to use sediment CO(2), however, with variable efficiency, and with the isoetid, Lobelia, as clearly the most effective and the elodeid, Ludwigia, as the least efficient. At a water column CO(2) concentration in equilibrium with air, Lobelia, Lilaeopsis and Vallisneria covered >75% of their CO(2) requirements by sediment uptake, and sediment CO(2) contributed substantially to photosynthesis at water CO(2) concentrations up to 1000 micromol L(-1). For all species except Ludwigia, the shoot to root ratio on an areal basis was the single factor best explaining variability in the importance of sediment CO(2). For Ludwigia, diffusion barriers limited uptake or transport from roots to stems and transport from stems to leaves. Submersed plants other than isoetids can utilize sediment CO(2), and small and medium sized elodeids with high root to shoot area in particular may benefit substantially from uptake of sediment CO(2) in low alkaline lakes.

  6. Subsurface oxide plays a critical role in CO2activation by Cu(111) surfaces to form chemisorbed CO2, the first step in reduction of CO2.

    Science.gov (United States)

    Favaro, Marco; Xiao, Hai; Cheng, Tao; Goddard, William A; Yano, Junko; Crumlin, Ethan J

    2017-06-27

    A national priority is to convert CO 2 into high-value chemical products such as liquid fuels. Because current electrocatalysts are not adequate, we aim to discover new catalysts by obtaining a detailed understanding of the initial steps of CO 2 electroreduction on copper surfaces, the best current catalysts. Using ambient pressure X-ray photoelectron spectroscopy interpreted with quantum mechanical prediction of the structures and free energies, we show that the presence of a thin suboxide structure below the copper surface is essential to bind the CO 2 in the physisorbed configuration at 298 K, and we show that this suboxide is essential for converting to the chemisorbed CO 2 in the presence of water as the first step toward CO 2 reduction products such as formate and CO. This optimum suboxide leads to both neutral and charged Cu surface sites, providing fresh insights into how to design improved carbon dioxide reduction catalysts.

  7. Experience with CO2 Eor Process in Hungary Expérience du procédé de récupération assistée du pétrole par le CO2 en Hongrie

    Directory of Open Access Journals (Sweden)

    Nemeth G.

    2006-11-01

    Full Text Available In Hungary, the CO2 injection EOR technology began in the mid 1960s. Since then, this method has achieved a wide range of field applications. Its special feature is that there is no miscibility. This article describes two types of field application: using CO2 in sandstone reservoirs and in karstic- limestone ones. The mechanism of displacement in such reservoirs is quite different. This article summarizes the exploitation technology used and its development, field experience and results, considering sandstone and the karstic reservoirs separately. La récupération assistée du pétrole par injection de CO2 a débuté en Hongrie au milieu des années 60. Depuis lors, cette méthode a été largement développée dans des applications à l'échelle du gisement. La caractéristique principale de cette méthode est qu'il n'y a pas de miscibilité. Les auteurs développent dans cet article deux types d'application sur champ : l'utilisation du CO2 dans le cas, d'une part de réservoirs gréseux et d'autre part de réservoirs karstiques-calca ires. Le mécanisme du déplacement dans ces deux types de réservoirs est assez différent. Cet article résume la technologie d'exploitation utilisée, ainsi que son développement, les expériences sur champ et les résultats obtenus, en considérant séparément les réservoirs gréseux et karstiques.

  8. Dynamics of soil CO 2 efflux under varying atmospheric CO 2 concentrations reveal dominance of slow processes

    Science.gov (United States)

    Dohyoung Kim; Ram Oren; James S. Clark; Sari Palmroth; A. Christopher Oishi; Heather R. McCarthy; Chris A. Maier; Kurt Johnsen

    2017-01-01

    We evaluated the effect on soil CO2 efflux (FCO2) of sudden changes in photosynthetic rates by altering CO2 concentration in plots subjected to +200 ppmv for 15 years. Five-day intervals of exposure to elevated CO2 (eCO2) ranging 1.0–1.8 times ambient did not affect FCO2. FCO2 did not decrease until 4 months after termination of the long-term eCO2 treatment, longer...

  9. Development of a stable MnCo2O4 cocatalyst for photocatalytic CO2 reduction with visible light.

    Science.gov (United States)

    Wang, Sibo; Hou, Yidong; Wang, Xinchen

    2015-02-25

    The synthesis of uniform MnCo2O4 microspheres and their cooperation with a visible light harvester to achieve efficient photocatalytic CO2 reduction under ambient conditions are reported here. The MnCo2O4 materials were prepared by a facile two-step solvothermal-calcination method and were characterized by XRD, SEM, TEM, EDX, XPS, elemental mapping, and N2 adsorption measurements. By using the MnCo2O4 microspheres as a heterogeneous cocatalyst, the photocatalytic performance of the CO2-to-CO conversion catalysis was remarkably enhanced, and no decrease in the promotional effect of the cocatalyst was observed after repeatedly operating the reaction for six cycles. (13)CO2 isotope tracer experiments verified that the CO product originated from the CO2 reactant. The effect of synthetic conditions and various reaction parameters on the photocatalytic activity of the system were investigated and optimized. The stability of the MnCo2O4 cocatalyst in the CO2 reduction system was confirmed by several techniques. Moreover, a possible mechanism for MnCo2O4-cocatalyzed CO2 photoreduction catalysis is proposed.

  10. Research on the physical properties of supercritical CO2 and the log evaluation of CO2-bearing volcanic reservoirs

    Science.gov (United States)

    Pan, Baozhi; Lei, Jian; Zhang, Lihua; Guo, Yuhang

    2017-10-01

    CO2-bearing reservoirs are difficult to distinguish from other natural gas reservoirs during gas explorations. Due to the lack of physical parameters for supercritical CO2, particularly neutron porosity, at present a hydrocarbon gas log evaluation method is used to evaluate CO2-bearing reservoirs. The differences in the physical properties of hydrocarbon and CO2 gases have led to serious errors. In this study, the deep volcanic rock of the Songliao Basin was the research area. In accordance with the relationship between the density and acoustic velocity of supercritical CO2 and temperature and pressure, the regularity between the CO2 density and acoustic velocity, and the depth of the area was established. A neutron logging simulation was completed based on a Monte Carlo method. Through the simulation of the wet limestone neutron logging, the relationship between the count rate ratio of short and long space detectors and the neutron porosity was acquired. Then, the nature of the supercritical CO2 neutron moderation was obtained. With consideration given to the complexity of the volcanic rock mineral composition, a volcanic rock volume model was established, and the matrix neutron and density parameters were acquired using the ECS log. The properties of CO2 were applied in the log evaluation of the CO2-bearing volcanic reservoirs in the southern Songliao Basin. The porosity and saturation of CO2 were obtained, and a reasonable application was achieved in the CO2-bearing reservoir.

  11. Canopy CO2 exchange of sugar beet under different CO2 concentrations and nitrogen supply: results from a free-air CO2 enrichment study.

    Science.gov (United States)

    Burkart, S; Manderscheid, R; Weigel, H-J

    2009-11-01

    Sugar beet (Beta vulgaris ssp. altissima Döll) was grown in the field under free-air CO(2) enrichment (FACE, 550 ppm) and different nitrogen (N) supply (2001: 126 (N100) and 63 kg.ha(-1) (N50); 2004: 156 (N100) and 75 kg.ha(-1)) during two crop rotations. Canopy CO(2) exchange rates (CCER) were measured during the main growth phase (leaf area index > or =2) using a dynamic chamber system. Canopy CO(2) exchange data were analysed with respect to treatment effects on seasonal means and light use efficiency and light response characteristics. CO(2) enrichment enhanced CCER throughout the season. However, in both years, CCER declined after the second half of August independent of radiation and [CO(2)]. Elevated [CO(2)] strongly stimulated CCER on a seasonal basis, whereas the reduction of CCER caused by low N was below 10% and not significant. There were no effects of N on daily radiation use efficiency of carbon gain calculated from CCER data, but a strong enhancement by CO(2) enrichment. CCER closely tracked diurnal variations in incident photosynthetic photon flux density (PPFD, mumol.m(-2).s(-1)). The relationship between CCER and incident PPFD was curvilinear. In both seasons, initial slopes and maximum rates (CCER(max)) were determined from two 6-day periods using these relationships. The first period was measured after canopy closure (first half of July) and the second in the second half of August. In the first period, elevated [CO(2)] increased the initial slopes. Low N supply affected neither the initial slopes nor their response to elevated [CO(2)] in either period. In contrast to initial slopes, N stress limited the [CO(2)] response of CCER(max) in the first period. In the second period, however, this interaction of [CO(2)] and N on CCER(max) was completely dominated by a general decline of CCER(max) whereas no general decline of the initial slopes occurred in the second period. This response of light response parameters to [CO(2)] and N suggests that, in

  12. Microbial growth under a high-pressure CO2 environment

    Science.gov (United States)

    Thompson, J. R.; Hernandez, H. H.

    2009-12-01

    Carbon capture and storage (CCS) of CO2 has the potential to significantly reduce the emission of greenhouse gasses associated with fossil fuel combustion. The largest potential for storing captured CO2 in the United Sates is in deep geologic saline formations. Currently, little is known about the effects of CO2 storage on biologically active microbial communities found in the deep earth biosphere. Therefore, to investigate how deep earth microbial communities will be affected by the storage of CO2, we have built a high-pressure microbial growth system in which microbial samples are subjected to a supercritical CO2 (scCO2) environment. Recently we have isolated a microbial consortium that is capable of growth and extracellular matrix production in nutrient media under a supercritical CO2 headspace. This consortium was cultivated from hydrocarbon residues associated with saline formation waters and includes members of the gram-positive Bacillus genus. The cultivation of actively growing cells in an environment containing scCO2 is unexpected based on previous experimental evidence of microbial sterilization attributed to the acidic, desiccating, and solvent-like properties of scCO2. Such microbial consortia have potential for development as (i) biofilm barriers for geological carbon-dioxide sequestration, and as (ii) agents of biocatalysis in environmentally-friendly supercritical (sc) CO2 solvent systems. The discovery that microbes can remain biologically active, and grow, in these environments opens new frontiers for the use of self-regenerating biological systems in engineering applications.

  13. Metal-Free Carbon Materials for CO2 Electrochemical Reduction.

    Science.gov (United States)

    Duan, Xiaochuan; Xu, Jiantie; Wei, Zengxi; Ma, Jianmin; Guo, Shaojun; Wang, Shuangyin; Liu, Huakun; Dou, Shixue

    2017-11-01

    The rapid increase of the CO2 concentration in the Earth's atmosphere has resulted in numerous environmental issues, such as global warming, ocean acidification, melting of the polar ice, rising sea level, and extinction of species. To search for suitable and capable catalytic systems for CO2 conversion, electrochemical reduction of CO2 (CO2 RR) holds great promise. Emerging heterogeneous carbon materials have been considered as promising metal-free electrocatalysts for the CO2 RR, owing to their abundant natural resources, tailorable porous structures, resistance to acids and bases, high-temperature stability, and environmental friendliness. They exhibit remarkable CO2 RR properties, including catalytic activity, long durability, and high selectivity. Here, various carbon materials (e.g., carbon fibers, carbon nanotubes, graphene, diamond, nanoporous carbon, and graphene dots) with heteroatom doping (e.g., N, S, and B) that can be used as metal-free catalysts for the CO2 RR are highlighted. Recent advances regarding the identification of active sites for the CO2 RR and the pathway of reduction of CO2 to the final product are comprehensively reviewed. Additionally, the emerging challenges and some perspectives on the development of heteroatom-doped carbon materials as metal-free electrocatalysts for the CO2 RR are included. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Waste benefits of CO2 policies in Japan.

    Science.gov (United States)

    Gielen, D J; Moriguchi, Y

    2002-02-01

    A linear programming model REAP (Regional Environmental strategy Analysis Program) has been developed for the analysis of the consequences of a CO2 tax for petrochemical products such as plastics (CO2, carbon dioxide, is the most important greenhouse gas). Special attention has been paid to the impacts on waste management. The results suggest that a 10,000 Y t(-1) CO2 tax would result in a significant reduction of CO2 emissions in the petrochemical life cycle, ranging from 40 Mt in 2015 to 70 Mt CO2 in later decades (more than 50% emission reduction). Waste quantities will be reduced simultaneously. The CO2 tax results in an 18% reduction of plastic waste weight in 2015 (3 Mt waste). Lower tax levels that may be politically more acceptable would result in proportionally lower environmental benefits. CO2 benefits and waste benefits of a CO2 tax are of equal importance in policy terms. Apart from changes in waste volume, CO2 taxes would affect the cost-effectiveness of waste handling technologies. Energy recovery in industrial kilns may replace conventional waste incineration. Recycling constitutes half of the total waste treatment. Given these results, current investments in new incineration capacity may suffer from insufficient waste availability during the next two decades in case CO2 taxes are introduced. A third effect of a CO2 tax is a significant increase of waste transportation. The results show that this increase is concentrated in the central part of Honshu (Kinki, Chubu & Kanto). Such transportation can result in new local environmental impacts that should be analysed in more detail. Given the strong impact of CO2 taxes on waste quantities and waste treatment it is recommended to co-ordinate CO2 policies and solid waste policies.

  15. Forecasting CO2 emissions in the Persian Gulf States

    Directory of Open Access Journals (Sweden)

    F.A. Olabemiwo

    2017-12-01

    Full Text Available The Persian Gulf States (Bahrain. Iran, Iraq, Qatar, Saudi Arabia, Kuwait and United Arab Emirate have dominated the oil and gas sector since the discovery of oil in the region. They are the world largest producers of crude oil, producing about 35 and 25 percent of the world natural gas and crude oil respectively. The use of fossil fuels is directly linked to the release of CO2 into the environment. CO2 accounts for 58.8 percent of all greenhouse gases released via human activities, consequently, presenting a malign impact on the environment through climate change, global warming, biodiversity, acid rain and desertification among others. Due to its importance, the data on CO2 emission obtained from US EIA from 1980 – 2010 was regressed using least square techniques and projections were made to the year 2050. Results indicated that each country’s p-value was less than 0.05 which implies that the models can be used for predicting CO2 emissions into the future. The data shows the emission of CO2 by countries from the highest to the lowest in 2016 as: Iran (590.72 Mtonnes; 7.58 tonnes of CO2/person > Saudi Arabia (471.82 Mtonnes; 18 tonnes of CO2/person > UAE (218.58 Mtonnes; 41.31 tonnes of CO2/person > Iraq (114.01 Mtonees; 3.71 tonnes of CO2/person > Kuwait (92.58 Mtonnes; 36.31 tonnes of CO2/person > Qatar (68.26 Mtonnes; 37 tonnes of CO2/person > Bahrain (33.16 Mtonnes; 27.5 tonnes of CO2/person". The sequence from the country with highest emission (Iran to the country with lowest emission (Bahrain will remain the same until 2050. A projection depicting a 7.7 percent yearly increase in CO2 emission in the Persian Gulf States.

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

    Science.gov (United States)

    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).

  17. Biofiksasi CO2 Oleh Mikroalga Chlamydomonas sp dalam Photobioreaktor Tubular

    Directory of Open Access Journals (Sweden)

    Hadiyanto Hadiyanto

    2014-05-01

    Full Text Available Mikroalga memiliki potensi dalam membiofiksasi CO2 dan dapat dimanfaatkan untuk mengurangi kadar CO2 dalam gas pencemar. Pertumbuhan mikroalga sangat dipengaruhi oleh konsentrasi gas CO2 di dalam gas pencemar. Tujuan penelitian ini adalah untuk mengeetahui kemampuan mikroalga Chlamydomonas sp yang dikultivasi dalam photobioreaktor tubular dalam penyerapan gas CO2 serta untuk mengetahui konsentrasi maksimum gas CO2 dalam umpan untuk memproduksi biomasa mikroalga yang optimal. Percobaan dilakukan dnegan memvariasi laju alir dari 0.03 -0.071 L/menit dan konsentrasi CO2 dalam umpan 10-30%. Hasil penelitian menunjukkan bahwa biomasa mikroalga dapat diproduksi dengan maksimal dengan konsentrasi gas CO2 20% dengan laju alir 0.07 L/min. Semakin tinggi laju alir maka produksi biomasa alga semakin besar. Kecepatan pertumbuhan alga maksimum terjadi pada 0.31 /hari. Pada konsentrasi gas CO2 30%, terjadi substrate inhibition yang disebabkan carbon dalam bentuk ion bicarbonate tidak dapat dikonsumsi lagi di dalam kultur alga. Kata kunci : Mikroalga, chlamydomonas sp, biofiksasi CO2, biogas Abstract Microalgae have a potential for CO2 biofixation and therefore can be used to reduce the CO2 concentration in the gas pollutants. Moreover, microalgae growth is strongly affected by the concentration of CO2 in the exhaust gas pollutants. The objective of this research was to investigate the ability of microalgae Chlamydomonas sp which was cultivated in a tubular photobioreactor for CO2 absorption as well as to determine the maximum concentration of CO2 in the feed gas to obtain optimum microalgae biomass. The experiments were performed by varying the gas flow rate of 0.03 -0.071 L / min and the concentration of CO2 in the feed of 10-30%. The results showed that the maximum biomass of microalgae can be produced with CO2 concentration of 20% vol with a flow rate of 0.07 L / min. The result also showed that increasing the gas flow rate, the greater of the production of

  18. Air-sea CO2 fluxes along the coast of Chile: From CO2 outgassing in central northern upwelling waters to CO2 uptake in southern Patagonian fjords

    OpenAIRE

    Torres, Rodrigo; Duarte, Carlos M.; Ruiz-Halpern, Sergio; Fukasawa, Masao

    2011-01-01

    Carbon system parameters measured during several expeditions along the coast of Chile (23°S-56°S) have been used to show the main spatial and temporal trends of air-sea CO2 fluxes in the coastal waters of the eastern South Pacific. Chilean coastal waters are characterized by strong pCO2 gradients between the atmosphere and the surface water, with high spatial and temporal variability. On average, the direction of the carbon flux changes from CO2 outgassing at the coastal upwelling region to C...

  19. Recent enlightening strategies for co2 capture: a review

    Science.gov (United States)

    Yuan, Peng; Qiu, Ziyang; Liu, Jia

    2017-05-01

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

  20. Financial development and sectoral CO2emissions in Malaysia.

    Science.gov (United States)

    Maji, Ibrahim Kabiru; Habibullah, Muzafar Shah; Saari, Mohd Yusof

    2017-03-01

    The paper examines the impacts of financial development on sectoral carbon emissions (CO 2 ) for environmental quality in Malaysia. Since the financial sector is considered as one of the sectors that will contribute to Malaysian economy to become a developed country by 2020, we utilize a cointegration method to investigate how financial development affects sectoral CO 2 emissions. The long-run results reveal that financial development increases CO 2 emissions from the transportation and oil and gas sector and reduces CO 2 emissions from manufacturing and construction sectors. However, the elasticity of financial development is not significant in explaining CO 2 emissions from the agricultural sector. The results for short-run elasticities were also consistent with the long-run results. We conclude that generally, financial development increases CO 2 emissions and reduces environmental quality in Malaysia.

  1. A Circular Bioeconomy with Biobased Products from CO2 Sequestration.

    Science.gov (United States)

    Venkata Mohan, S; Modestra, J Annie; Amulya, K; Butti, Sai Kishore; Velvizhi, G

    2016-06-01

    The unprecedented climate change influenced by elevated concentrations of CO2 has compelled the research world to focus on CO2 sequestration. Although existing natural and anthropogenic CO2 sinks have proven valuable, their ability to further assimilate CO2 is now questioned. Thus, we highlight here the importance of biological sequestration methods as alternate and viable routes for mitigating climate change while simultaneously synthesizing value-added products that could sustainably fuel the circular bioeconomy. Four conceptual models for CO2 biosequestration and the synthesis of biobased products, as well as an integrated CO2 biorefinery model, are proposed. Optimizing and implementing this biorefinery model might overcome the limitations of existing sequestration methods and could help realign the carbon balance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. CO2 measurements during transcranial Doppler examinations in headache patients

    DEFF Research Database (Denmark)

    Thomsen, L L; Iversen, Helle Klingenberg

    1994-01-01

    Transcranial Doppler (TCD) examinations are increasingly being used in studies of headache pathophysiology. Because blood velocity is highly dependent on PCO2, these parameters should be measured simultaneously. The most common way of performing measurements during TCD examinations is as end......-tidal pCO2 with a capnograph. When patients are nauseated and vomit, as in migraine, the mask or mouthpiece connected to the capnograph represents a problem. We therefore evaluated whether a transcutaneous pCO2 electrode was as useful as the capnograph for pCO2 measurements in TCD examinations. We...... conclude that this is not the case, and recommend capnographic end-tidal pCO2 measurements during TCD examinations. However, transcutaneous pCO2 measurements may represent a supplement to spot measurements of end-tidal pCO2 in stable conditions when long-term monitoring is needed, and the mask...

  3. CO2 Storage related Groundwater Impacts and Protection

    Science.gov (United States)

    Fischer, Sebastian; Knopf, Stefan; May, Franz; Rebscher, Dorothee

    2016-03-01

    Injection of CO2 into the deep subsurface will affect physical and chemical conditions in the storage environment. Hence, geological CO2 storage can have potential impacts on groundwater resources. Shallow freshwater can only be affected if leakage pathways facilitate the ascent of CO2 or saline formation water. Leakage associated with CO2 storage cannot be excluded, but potential environmental impacts could be reduced by selecting suitable storage locations. In the framework of risk assessment, testing of models and scenarios against operational data has to be performed repeatedly in order to predict the long-term fate of CO2. Monitoring of a storage site should reveal any deviations from expected storage performance, so that corrective measures can be taken. Comprehensive R & D activities and experience from several storage projects will enhance the state of knowledge on geological CO2 storage, thus enabling safe storage operations at well-characterised and carefully selected storage sites while meeting the requirements of groundwater protection.

  4. Climate-dependent CO2 emissions from lakes

    Science.gov (United States)

    Kosten, Sarian; Roland, FáBio; da Motta Marques, David M. L.; van Nes, Egbert H.; Mazzeo, NéStor; Sternberg, Leonel Da S. L.; Scheffer, Marten; Cole, Jon J.

    2010-06-01

    Inland waters, just as the world's oceans, play an important role in the global carbon cycle. While lakes and reservoirs typically emit CO2, they also bury carbon in their sediment. The net CO2 emission is largely the result of the decomposition or preservation of terrestrially supplied carbon. What regulates the balance between CO2 emission and carbon burial is not known, but climate change and temperature have been hypothesized to influence both processes. We analyzed patterns in carbon dioxide partial pressure (pCO2) in 83 shallow lakes over a large climatic gradient in South America and found a strong, positive correlation with temperature. The higher pCO2 in warmer lakes may be caused by a higher, temperature-dependent mineralization of organic carbon. This pattern suggests that cool lakes may start to emit more CO2 when they warm up because of climate change.

  5. Non-CO2 greenhouse gases and climate change.

    Science.gov (United States)

    Montzka, S A; Dlugokencky, E J; Butler, J H

    2011-08-03

    Earth's climate is warming as a result of anthropogenic emissions of greenhouse gases, particularly carbon dioxide (CO(2)) from fossil fuel combustion. Anthropogenic emissions of non-CO(2) greenhouse gases, such as methane, nitrous oxide and ozone-depleting substances (largely from sources other than fossil fuels), also contribute significantly to warming. Some non-CO(2) greenhouse gases have much shorter lifetimes than CO(2), so reducing their emissions offers an additional opportunity to lessen future climate change. Although it is clear that sustainably reducing the warming influence of greenhouse gases will be possible only with substantial cuts in emissions of CO(2), reducing non-CO(2) greenhouse gas emissions would be a relatively quick way of contributing to this goal.

  6. CO2 emission benefit of diesel (versus gasoline) powered vehicles.

    Science.gov (United States)

    Sullivan, J L; Baker, R E; Boyer, B A; Hammerle, R H; Kenney, T E; Muniz, L; Wallington, T J

    2004-06-15

    Concerns regarding global warming have increased the pressure on automobile manufacturers to decrease emissions of CO2 from vehicles. Diesel vehicles have higher fuel economy and lower CO2 emissions than their gasoline counterparts. Increased penetration of diesel powered vehicles into the market is a possible transition strategy toward a more sustainable transportation system. To facilitate discussions regarding the relative merits of diesel vehicles it is important to have a clear understanding of their CO2 emission benefits. Based on European diesel and gasoline certification data, this report quantifies such CO2 reduction opportunities for cars and light duty trucks in today's vehicles and those in the year 2015. Overall, on a well-to-wheels per vehicle per mile basis, the CO2 reduction opportunity for today's vehicles is approximately 24-33%. We anticipate that the gap between diesel and gasoline well-to-wheel vehicle CO2 emissions will decrease to approximately 14-27% by the year 2015.

  7. Mixing of two miscible fluids at high Schmidt number

    Science.gov (United States)

    Simmons, Mark; Alberini, Federico; Pain, Christopher; Matar, Omar

    2013-11-01

    The blending of two miscible liquids at high Schmidt number is an increasingly common industrial problem: as processes push towards shorter timescales yet the rheology of the fluids becomes increasingly complex. This leads to phenomena which resemble a quasi two-phase system with zero interfacial tension. In this study, we compare experimental results with computational fluid dynamics simulations using unstructured-mesh adaptivity for the flow of two Newtonian, or two power-law fluids through a complex geometry representative of a Kenics type static mixer used in industry. The geometry induces a stretching and folding of the fluid elements which causes exponential growth of the interface length down the geometry. The interfacial topology obtained from the simulations is compared with experiments carried out using Planar Laser Induced Fluorescence (PLIF), which enables the spatial distribution of each phase, and the interfaces between them, to be determined at the outlet of the geometry. EPSRC Programme Grant EP/K003976/1.

  8. Miscible viscous fingering involving production of gel by chemical reactions

    Science.gov (United States)

    Nagatsu, Yuichiro; Hoshino, Kenichi

    2015-11-01

    We have experimentally investigated miscible viscous fingering with chemical reactions producing gel. Here, two systems were employed. In one system, sodium polyacrylate (SPA) solution and aluminum ion (Al3 +) solution were used as the more and less viscous liquids, respectively. In another system, SPA solution and ferric ion (Fe3 +) solution were used as the more and less viscous liquids, respectively. In the case of Al3 +, displacement efficiency was smaller than that in the non-reactive case, whereas in the case of Fe3 +, the displacement efficiency was larger. We consider that the difference in change of the patterns in the two systems will be caused by the difference in the properties of the gels. Therefore, we have measured the rheological properties of the gels by means of a rheometer. We discuss relationship between the VF patterns and the rheological measurement.

  9. Calculation of minimum miscibility pressure using fast slimtube simulation

    DEFF Research Database (Denmark)

    Yan, Wei; Michelsen, Michael Locht; Stenby, Erling Halfdan

    2012-01-01

    Minimum misciblility pressure (MMP) is a critical parameter in designing a miscible gas injection process. It is expected that 100% displacement efficiency on the microscopic scale can be achieved provided the injection pressure is above MMP. Two approaches are usually employed for equation...... of state (EoS) based MMP calculation. The slimtube simulation approach is a numerical simulation of the physical slimtube experiment, which is commonly accepted as the most reliable experimental method for MMP determination. This approach carries out slimtube simulation runs at a series of pressures...... and determines the MMP from the recovery-pressure curve, just as in the experiment. The global approach, which is based on the method of characteristics analysis of 1D gas injection, finds the MMP by locating the pressure where a key tie-line becomes critical. Although the global approach is faster, the slimtube...

  10. Transport Mechanisms for CO2-CH4 Exchange and Safe CO2 Storage in Hydrate-Bearing Sandstone

    Directory of Open Access Journals (Sweden)

    Knut Arne Birkedal

    2015-05-01

    Full Text Available CO2 injection in hydrate-bearing sediments induces methane (CH4 production while benefitting from CO2 storage, as demonstrated in both core and field scale studies. CH4 hydrates have been formed repeatedly in partially water saturated Bentheim sandstones. Magnetic Resonance Imaging (MRI and CH4 consumption from pump logs have been used to verify final CH4 hydrate saturation. Gas Chromatography (GC in combination with a Mass Flow Meter was used to quantify CH4 recovery during CO2 injection. The overall aim has been to study the impact of CO2 in fractured and non-fractured samples to determine the performance of CO2-induced CH4 hydrate production. Previous efforts focused on diffusion-driven exchange from a fracture volume. This approach was limited by gas dilution, where free and produced CH4 reduced the CO2 concentration and subsequent driving force for both diffusion and exchange. This limitation was targeted by performing experiments where CO2 was injected continuously into the spacer volume to maintain a high driving force. To evaluate the effect of diffusion length multi-fractured core samples were used, which demonstrated that length was not the dominating effect on core scale. An additional set of experiments is presented on non-fractured samples, where diffusion-limited transportation was assisted by continuous CO2 injection and CH4 displacement. Loss of permeability was addressed through binary gas (N2/CO2 injection, which regained injectivity and sustained CO2-CH4 exchange.

  11. Numerical Study on CO2-Brine-Rock Interaction of Enhanced Geothermal Systems with CO2 as Heat Transmission Fluid

    Directory of Open Access Journals (Sweden)

    Wan Yuyu

    2016-01-01

    Full Text Available Enhanced Geothermal Systems (EGS with CO2 instead of water as heat transmission fluid is an attractive concept for both geothermal resources development and CO2 geological sequestration. Previous studies show that CO2 has lots of favorable properties as heat transmission fluid and also can offer geologic storage of CO2 as an ancillary benefit. However, after CO2 injection into geological formations, chemical reaction between brine and rock can change chemical characteristics of saline and properties of rock such as porosity and permeability. Is this advantage or disadvantage for EGS operating? To answer this question, we have performed chemically reactive transport modeling to investigate fluid-rock interactions and CO2 mineral carbonation of Enhanced Geothermal Systems (EGS site at Desert Peak (Nevada operated with CO2. The simulation results show that (1 injection CO2 can create a core zone fulfilled with CO2 as main working domain for EGS, and (2 CO2 storage can induced self-enhancing alteration of EGS.

  12. Implications of overestimated anthropogenic CO2 emissions on East Asian and global land CO2 flux inversion

    Science.gov (United States)

    Saeki, Tazu; Patra, Prabir K.

    2017-12-01

    Measurement and modelling of regional or country-level carbon dioxide (CO2) fluxes are becoming critical for verification of the greenhouse gases emission control. One of the commonly adopted approaches is inverse modelling, where CO2 fluxes (emission: positive flux, sink: negative flux) from the terrestrial ecosystems are estimated by combining atmospheric CO2 measurements with atmospheric transport models. The inverse models assume anthropogenic emissions are known, and thus the uncertainties in the emissions introduce systematic bias in estimation of the terrestrial (residual) fluxes by inverse modelling. Here we show that the CO2 sink increase, estimated by the inverse model, over East Asia (China, Japan, Korea and Mongolia), by about 0.26 PgC year-1 (1 Pg = 1012 g) during 2001-2010, is likely to be an artifact of the anthropogenic CO2 emissions increasing too quickly in China by 1.41 PgC year-1. Independent results from methane (CH4) inversion suggested about 41% lower rate of East Asian CH4 emission increase during 2002-2012. We apply a scaling factor of 0.59, based on CH4 inversion, to the rate of anthropogenic CO2 emission increase since the anthropogenic emissions of both CO2 and CH4 increase linearly in the emission inventory. We find no systematic increase in land CO2 uptake over East Asia during 1993-2010 or 2000-2009 when scaled anthropogenic CO2 emissions are used, and that there is a need of higher emission increase rate for 2010-2012 compared to those calculated by the inventory methods. High bias in anthropogenic CO2 emissions leads to stronger land sinks in global land-ocean flux partitioning in our inverse model. The corrected anthropogenic CO2 emissions also produce measurable reductions in the rate of global land CO2 sink increase post-2002, leading to a better agreement with the terrestrial biospheric model simulations that include CO2-fertilization and climate effects.

  13. CO2 laser welding of magnesium alloys

    Science.gov (United States)

    Dhahri, Mohammed; Masse, Jean Eric; Mathieu, J. F.; Barreau, Gerard; Autric, Michel L.

    2000-02-01

    Metallic alloys with a low mass density can be considered to be basic materials in aeronautic and automotive industry. Magnesium alloys have better properties than aluminum alloys in respect of their low density and high resistance to traction. The main problems of magnesium alloy welding are the inflammability, the crack formation and the appearance of porosity during the solidification. The laser tool is efficient to overcome the difficulties of manufacturing by conventional processing. Besides, the laser processing mainly using shielding gases allows an effective protection of the metal against the action of oxygen and a small heat affected zone. In this paper, we present experimental results about 5 kW CO2 laser welding of 4 mm-thick magnesium alloy plates provided by Eurocopter France. The focused laser beam has about 0.15 mm of diameter. We have investigated the following sample: WE43, alloy recommended in aeronautic and space applications, is constituted with Mg, Y, Zr, rare earth. More ductile, it can be used at high temperatures until 250 degrees Celsius for times longer than 5000 hours without effects on its mechanical properties. A sample of RZ5 (French Norm: GZ4TR, United States Norm ZE41) is composed of Mg, Zn, Zr, La, rare earth. This alloy has excellent properties of foundry and it allows to the realization of components with complex form. Also, it has a good resistance and important properties of tightness. The parameters of the process were optimized in the following fields: laser power: 2 to 5 kW, welding speed: 1 to 4.5 m/min, focal position: -3 mm to +3 mm below or on the top of the metal surface, shielding gas: helium with a flow of 10 to 60 l/min at 4 bars. Metallurgical analyses and mechanical control are made (macroscopic structure, microscopic structure, interpretations of the structures and localization of possible defects, analyse phases, chemical composition, hardness, tensile test etc.) to understand the parameters influence of welding

  14. Global CO2 Levels and the Calvin Cycle

    Science.gov (United States)

    1990-01-01

    half of the total CO2 fixed world-wide is processed by marine algae . Presently, three mechanisms have been described by which CO 2 may be...information on the autotrophic process in eukaryotes has been derived almost exclusively from terrestrial plants and green algae (the Chlorophyta...However, two additional supertaxa of plants also fix CO 2. The Chromophyta represent a large assemblage of algae that include the diatoms and

  15. CO2 hydrogenation to hydrocarbons over iron nanoparticles ...

    Indian Academy of Sciences (India)

    Hydrogenation of CO2 to hydrocarbons over iron nanoparticles supported on oxygen- functionalized multi-walled carbon nanotubes was studied in a fixed-bed U-tube reactor at 25 bar with a. H2:CO2 ratio of 3. Conversion of CO2 was approximately 35% yielding C1–C5 products at 360. ◦. C with methane and CO as major ...

  16. Holiday CO2: Inference from the Salt Lake City data

    Science.gov (United States)

    Ryoo, J.; Fung, I. Y.; Ehleringer, J. R.; Stephens, B. B.

    2013-12-01

    A network of high-frequency CO2 sensors has been established in Salt Lake City (SLC), Utah (http://co2.utah.edu/), and the annual/monthly pattern of CO2 variability is consistent with a priori estimates of CO2 fluxes (McKain et al., 2012). Here we ask if short-term changes in anthropogenic sources can be detected, and present a case study of Thanksgiving holiday, when traffic and energy use patterns are expected to be different from that during the rest of the month. CO2 mole fraction is much higher during the Thanksgiving holidays than the other days in November 2008 for all 5 sites in SLC, and a similar pattern is found in other years. Taking into account that the wind speed is relatively low in downtown SLC compared to the other SLC sites, the downtown site is further investigated to minimize the meteorological influence on CO2. In order to understand the relative contributions to the high level of CO2 during the Thanksgiving holidays, we carried out a multiple linear regression (MLR) analysis of the rate of CO2 change against various sources. Mobile CO2 sources are assumed to be proportional to local traffic data and residential CO2 sources are assumed to depend exponentially on temperature. Vulcan data were used to specify the other anthropogenic sources (commercial, industrial, nonroad, electricity, aircraft, and cement). The MLR analysis shows that during the Thanksgiving holidays CO2 contributions from residential and commercial CO2 are larger than that during the rest of November, and mobile sources represent only a relatively small contribution. The study demonstrates the feasibility of detecting changes in urban source contributions using high-frequency measurements in combination with daily PBL height and local traffic volume data.

  17. Simulating Remediation of CO2 Leakage from Geological Storage Sites

    Science.gov (United States)

    Zhang, Y.; Oldenburg, C. M.; Benson, S. M.

    2003-12-01

    One strategy to reduce net greenhouse gas emissions is to inject carbon dioxide (CO2) deep into subsurface formations where presumably it would be stored indefinitely. Although geologic storage formations will be carefully selected, CO2 injected into a target formation may unexpectedly migrate upwards and ultimately seep out at the ground surface, creating a potential hazard to human beings and ecosystems. In this case, CO2 that has leaked from the geologic storage site is considered a contaminant, and remediation strategies such as passive venting and active pumping are needed. The purpose of this study is to investigate remediation strategies for CO2 leakage from geologic storage sites. We use the integral finite-difference code TOUGH2 to simulate the remediation of CO2 in subsurface systems. We consider the components of water, CO2 and air, and model flow and transport in aqueous and gas phases subject to a variety of initial and boundary conditions including passive venting and active pumping. We have investigated the time it takes for a gas plume of CO2 to be removed from the vadose zone both by natural attenuation processes and by active extraction wells. The time for removal is parameterized in terms of a CO2 plume half-life, defined as the time required for one-half of the CO2 mass to be removed. Initial simulations show that barometric pressure fluctuations enhance the removal of CO2 from the vadose zone, but that CO2 trapped near the water table is difficult to remove by either passive or active remediation approaches. This work was supported by a Cooperative Research and Development Agreement (CRADA) between BP Corporation North America, as part of the CO2 Capture Project (CCP), and the U.S. Department of Energy (DOE) through the National Energy Technologies Laboratory (NETL), and by the U.S. Department of Energy under contract DE-AC03-76SF00098.

  18. CO2^{*} chemiluminescence study at low and elevated pressures

    Science.gov (United States)

    Kopp, M.; Brower, M.; Mathieu, O.; Petersen, E.; Güthe, F.

    2012-06-01

    Chemiluminescence experiments have been performed to assess the state of current CO2^{*} kinetics modeling. The difficulty with modeling CO2^{*} lies in its broad emission spectrum, making it a challenge to isolate it from background emission of species such as CH∗ and CH2O∗. Experiments were performed in a mixture of 0.0005H2+0.01N2O+0.03CO+0.9595Ar in an attempt to isolate CO2^{*} emission. Temperatures ranged from 1654 K to 2221 K at two average pressures, 1.4 and 10.4 atm. The unique time histories of the various chemiluminescence species in the unconventional mixture employed at these conditions allow for easy identification of the CO2^{*} concentration. Two different wavelengths to capture CO2^{*} were used; one optical filter was centered at 415 nm and the other at 458 nm. The use of these two different wavelengths was done to verify that broadband CO2^{*} was in fact being captured, and not emission from other species such as CH∗ and CH2O∗. As a baseline for time history and peak magnitude comparison, OH∗ emission was captured at 307 nm simultaneously with the two CO2^{*} filters. The results from the two CO2^{*} filters were consistent with each other, implying that indeed the same species (i.e., CO2^{*}) was being measured at both wavelengths. A first-generation kinetics model for CO2^{*} and CH2O∗ was developed, since no comprehensively validated one exists to date. CH2O∗ and CH∗ were ruled out as being present in the experiments at any measurable level, based on calculations and comparisons with the data. Agreement with the CO2^{*} model was only fair, which necessitates future improvements for a better understanding of CO2^{*} chemiluminescence as well as the kinetics of the ground state species.

  19. Corrosion studies on casing steel in CO2 storage environments

    NARCIS (Netherlands)

    Zhang, X.; Zevenbergen, J.F.; Benedictus, T.

    2013-01-01

    The corrosion behavior of casing steel N80 in brine plus CO2 was studied in autoclave to simulate the CO2 storage environment. The brine solution used in the study contained 130 g/l NaCl, 22.2 g/l CaCl2 and 4 g/l MgCl2. The CO2 was charged in the autoclave at different pressures (60, 80 and 100 bar)

  20. CO 2 hydrogenation to hydrocarbons over iron nanoparticles ...

    Indian Academy of Sciences (India)

    Hydrogenation of CO2 to hydrocarbons over iron nanoparticles supported on oxygenfunctionalized multi-walled carbon nanotubes was studied in a fixed-bed U-tube reactor at 25 bar with a H2:CO2 ratio of 3. Conversion of CO2 was approximately 35% yielding C1-C5 products at 360°C with methane and CO as major ...

  1. CO2 laser resurfacing of the face and neck.

    Science.gov (United States)

    Goldman, M P

    2001-05-01

    Laser resurfacing with the short-pulsed, high-energy CO2 laser has been used to treat photodamaged skin and acne scars. Efficacy and safety have been demonstrated with this technique since 1992. Newer treatment methods, including sequential or combination treatment with the Er:YAG laser have led to increased efficacy with a decrease in adverse sequelae. This article details the author's experience with CO2 laser resurfacing and promotes the use of sequential CO2/Er:YAG laser resurfacing.

  2. THE INFLUENCE OF CO2 ON WELL CEMENT

    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec

    2010-12-01

    Full Text Available Carbon capture and storage is one way to reduce emissions of greenhouse gases in the atmosphere. Underground gas storage operations and CO2 sequestration in aquifers relay on both the proper wellbore construction and sealing properties of the cap rock. CO2 injection candidates may be new wells or old wells. In both cases, the long-term wellbore integrity (up to 1 000 years is one of the key performance criteria in the geological storage of CO2. The potential leakage paths are the migration CO2 along the wellbore due to poor cementation and flow through the cap rock. The permeability and integrity of the set cement will determine how effective it is in preventing the leakage. The integrity of the cap rock is assured by an adequate fracture gradient and by sufficient set cement around the casing across the cap rock and without a micro-annulus. CO2 storage in underground formations has revived the researc of long term influence of the injected CO2 on Portland cements and methods for improving the long term efficiency of the wellbore sealant. Some researchers predicted that set cement will fail when exposed to CO2 leading to potential leakage to the atmosphere or into underground formations that may contain potable water. Other researchers show set cement samples from 30 to 50 year-old wells (CO2 EOR projects that have maintained sealing integrity and prevented CO2 leakage, in spite of some degree of carbonation. One of reasons for the discrepancy between certain research lab tests and actual field performance measurements is the absence of standard protocol for CO2 resistance-testing devices, conditions, or procedures. This paper presents potential flow paths along the wellbore, CO2 behaviour under reservoir conditions, and geochemical alteration of hydrated Portland cement due to supercritical CO2 injection.

  3. System-level modeling for geological storage of CO2

    OpenAIRE

    Zhang, Yingqi; Oldenburg, Curtis M.; Finsterle, Stefan; Bodvarsson, Gudmundur S.

    2006-01-01

    One way to reduce the effects of anthropogenic greenhouse gases on climate is to inject carbon dioxide (CO2) from industrial sources into deep geological formations such as brine formations or depleted oil or gas reservoirs. Research has and is being conducted to improve understanding of factors affecting particular aspects of geological CO2 storage, such as performance, capacity, and health, safety and environmental (HSE) issues, as well as to lower the cost of CO2 capture and related p...

  4. Activation of CO2 by supported Cu clusters.

    Science.gov (United States)

    Iyemperumal, Satish Kumar; Deskins, N Aaron

    2017-11-01

    Catalytic reduction of carbon dioxide to useful chemicals is a potent way to mitigate this greenhouse gas, but the challenge lies in finding active reduction catalysts. Using density functional theory we studied CO2 activation over TiO2-supported Cu clusters of size 1-4 atoms. The linear to bent transformation of CO2 is necessary for activation, and we found that all the clusters stabilized bent CO2, along with a significant gain of electrons on the CO2 (indicative of activation). On all the TiO2 supported Cu clusters, the interfacial sites were found to stabilize the bent CO2 adsorption, where the active site of adsorption on Cu dimer, trimer and tetramer was on the Cu atom farthest away from the TiO2 surface. Particularly, the Cu dimer stabilized bent CO2 very strongly, although this species was found to be unstable on the surface. A synthesis technique that could stabilize the Cu dimer could therefore lead to a very active catalyst. Furthermore we found (using vibrational and charge analysis) that the active sites for the CO2 activation predominantly had 0 and +1 oxidation states; the oxidation state of Cu is known to directly affect CO2 reduction activity. Our study shows TiO2-supported small Cu clusters can be active catalysts for CO2 reduction and also provides further motivation for theoretical and experimental studies of metal clusters.

  5. Investigation of CO2precursors in roasted coffee.

    Science.gov (United States)

    Wang, Xiuju; Lim, Loong-Tak

    2017-03-15

    Two CO 2 formation pathways (chlorogenic acid (CGA) degradation and Maillard reaction) during coffee roasting were investigated. CGA is shown not a major contributor to CO 2 formation, as heating of this compound under typical roasting conditions did not release a large quantity of CO 2 . However, heating of a CGA moiety, caffeic acid, resulted in high yield of CO 2 (>98%), suggesting that CGA hydrolysis could be the rate limiting step for CO 2 formation from CGA. A large amount of CO 2 was detected from glycine-sucrose model system under coffee roasting conditions, implying the importance of Maillard reactions in CO 2 formation. Further studies on the heating of various components isolated from green coffee beans showed that CO 2 was generated from various green coffee components, including water insoluble proteins and polysaccharides. Around 50% of CO 2 was formed from thermal reactions of lower molecular weight compounds that represent ∼25% by weight in green coffee. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. CO2 Emissions From Fuel Combustion. Highlights. 2013 Edition

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    In the lead-up to the UN climate negotiations in Warsaw, the latest information on the level and growth of CO2 emissions, their source and geographic distribution will be essential to lay the foundation for a global agreement. To provide input to and support for the UN process, the IEA is making available for free download the ''Highlights'' version of CO2 Emissions from Fuel Combustion now for sale on IEA Bookshop. This annual publication contains, for more than 140 countries and regions: estimates of CO2 emissions from 1971 to 2011; selected indicators such as CO2/GDP, CO2/capita, CO2/TPES and CO2/kWh; a decomposition of CO2 emissions into driving factors; and CO2emissions from international marine and aviation bunkers, key sources, and other relevant information. The nineteenth session of the Conference of the Parties to the Climate Change Convention (COP-19), in conjunction with the ninth meeting of the Parties to the Kyoto Protocol (CMP 9), met in Warsaw, Poland from 11 to 22 November 2013. This volume of ''Highlights'', drawn from the full-scale study, was specially designed for delegations and observers of the meeting in Warsaw.

  7. CO2 emissions from German drinking water reservoirs.

    Science.gov (United States)

    Saidi, Helmi; Koschorreck, Matthias

    2017-03-01

    Globally, reservoirs are a significant source of atmospheric CO2. However, precise quantification of greenhouse gas emissions from drinking water reservoirs on the regional or national scale is still challenging. We calculated CO2 fluxes for 39 German drinking water reservoirs during a period of 22years (1991-2013) using routine monitoring data in order to quantify total emission of CO2 from drinking water reservoirs in Germany and to identify major drivers. All reservoirs were a net CO2 source with a median flux of 167gCm-2y-1, which makes gaseous emissions a relevant process for the carbon budget of each reservoir. Fluxes varied seasonally with median fluxes of 13, 48, and 201gCm-2y-1 in spring, summer, and autumn respectively. Differences between reservoirs appeared to be primarily caused by the concentration of CO2 in the surface water rather than by the physical gas transfer coefficient. Consideration of short term fluctuations of the gas transfer coefficient due to varying wind speed had only a minor effect on the annual budgets. High CO2 emissions only occurred in reservoirs with pHemissions correlated exponentially with pH but not with dissolved organic carbon (DOC). There was significant correlation between land use in the catchment and CO2 emissions. In total, German drinking water reservoirs emit 44000t of CO2 annually, which makes them a negligible CO2 source (emissions) in Germany. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Atmospheric CO2 Variability Observed From ASCENDS Flight Campaigns

    Science.gov (United States)

    Lin, Bing; Browell, Edward; Campbell, Joel; Choi, Yonghoon; Dobler, Jeremy; Fan, Tai-Fang; Harrison, F. Wallace; Kooi, Susan; Liu, Zhaoyan; Meadows, Byron; hide

    2015-01-01

    Significant atmospheric CO2 variations on various spatiotemporal scales were observed during ASCENDS flight campaigns. For example, around 10-ppm CO2 changes were found within free troposphere in a region of about 200x300 sq km over Iowa during a summer 2014 flight. Even over extended forests, about 2-ppm CO2 column variability was measured within about 500-km distance. For winter times, especially over snow covered ground, relatively less horizontal CO2 variability was observed, likely owing to minimal interactions between the atmosphere and land surface. Inter-annual variations of CO2 drawdown over cornfields in the Mid-West were found to be larger than 5 ppm due to slight differences in the corn growing phase and meteorological conditions even in the same time period of a year. Furthermore, considerable differences in atmospheric CO2 profiles were found during winter and summer campaigns. In the winter CO2 was found to decrease from about 400 ppm in the atmospheric boundary layer (ABL) to about 392 ppm above 10 km, while in the summer CO2 increased from 386 ppm in the ABL to about 396 ppm in free troposphere. These and other CO2 observations are discussed in this presentation.

  9. A CO2-strategy for BTC [Belgian Development Agency

    Energy Technology Data Exchange (ETDEWEB)

    Bailly, J. [Prospect C and S, Brussels (Belgium); Hanekamp, E. [Partners for Innovation, Amsterdam (Netherlands)

    2008-09-15

    The CO2 footprint is determined the CO2 strategy is developed for the Belgian Technical Cooperation (BTC). BTC is the Belgian agency for development cooperation, and finances development projects in 23 partner countries. The CO2 footprint covered BTC's activities in 2007 in all their offices worldwide. Footprint and strategy were finalised and adopted by the Executive Board at the end of 2008. Meanwhile, the BTC began with the introduction of the proposed strategy. Partners for Innovation and Prospect were asked to support the introduction of the strategy and to determine the CO2 footprint of 2008.

  10. A practical CO2 flux remote sensing technique

    Science.gov (United States)

    Queisser, Manuel; Burton, Mike

    2017-04-01

    An accurate quantification of CO2 flux from both natural and anthropogenic sources is of great interest in various areas of the Earth, environmental and atmospheric sciences. As emitted excess CO2 quickly dilutes into the 400 ppm ambient CO2 concentration and degassing often occurs diffusively, measuring CO2 fluxes is challenging. Therefore, fluxes are usually derived from grids of in-situ measurements, which are labour intensive measurements. Other than a safe measurement distance, remote sensing offers quick, spatially integrated and thus a more thorough measurement of gas fluxes. Active remote sensing combines these merits with operation independent of sunlight or clear sky conditions. Due to their weight and size, active remote sensing platforms for CO2, such as LIDAR, cannot easily be applied in the field or transported overseas. Moreover, their complexity requires a rather lengthy setup procedure to be undertaken by skilled personal. To meet the need for a rugged, practical CO2 remote sensing technique to scan volcanic plumes, we have developed the CO2 LIDAR. It measures 1-D column densities of CO2 with sufficient sensitivity to reveal the contribution of magmatic CO2. The CO2 LIDAR has been mounted inside a small aircraft and used to measure atmospheric column CO2 concentrations between the aircraft and the ground. It was further employed on the ground, measuring CO2 emissions from mud volcanism. During the measurement campaign the CO2 LIDAR demonstrated reliability, portability, quick set-up time (10 to 15 min) and platform independence. This new technique opens the possibility of rapid, comprehensive surveys of point source, open-vent CO2 emissions, as well as emissions from more diffuse sources such as lakes and fumarole fields. Currently, within the proof-of-concept ERC project CarbSens, a further reduction in size, weight and operational complexity is underway with the goal to commercialize the platform. Areas of potential applications include fugitive

  11. Efficient electrochemical CO2 conversion powered by renewable energy.

    Science.gov (United States)

    Kauffman, Douglas R; Thakkar, Jay; Siva, Rajan; Matranga, Christopher; Ohodnicki, Paul R; Zeng, Chenjie; Jin, Rongchao

    2015-07-22

    The catalytic conversion of CO2 into industrially relevant chemicals is one strategy for mitigating greenhouse gas emissions. Along these lines, electrochemical CO2 conversion technologies are attractive because they can operate with high reaction rates at ambient conditions. However, electrochemical systems require electricity, and CO2 conversion processes must integrate with carbon-free, renewable-energy sources to be viable on larger scales. We utilize Au25 nanoclusters as renewably powered CO2 conversion electrocatalysts with CO2 → CO reaction rates between 400 and 800 L of CO2 per gram of catalytic metal per hour and product selectivities between 80 and 95%. These performance metrics correspond to conversion rates approaching 0.8-1.6 kg of CO2 per gram of catalytic metal per hour. We also present data showing CO2 conversion rates and product selectivity strongly depend on catalyst loading. Optimized systems demonstrate stable operation and reaction turnover numbers (TONs) approaching 6 × 10(6) molCO2 molcatalyst(-1) during a multiday (36 h total hours) CO2 electrolysis experiment containing multiple start/stop cycles. TONs between 1 × 10(6) and 4 × 10(6) molCO2 molcatalyst(-1) were obtained when our system was powered by consumer-grade renewable-energy sources. Daytime photovoltaic-powered CO2 conversion was demonstrated for 12 h and we mimicked low-light or nighttime operation for 24 h with a solar-rechargeable battery. This proof-of-principle study provides some of the initial performance data necessary for assessing the scalability and technical viability of electrochemical CO2 conversion technologies. Specifically, we show the following: (1) all electrochemical CO2 conversion systems will produce a net increase in CO2 emissions if they do not integrate with renewable-energy sources, (2) catalyst loading vs activity trends can be used to tune process rates and product distributions, and (3) state-of-the-art renewable-energy technologies are sufficient

  12. Supported Catalysts for CO2 Methanation: A Review

    Directory of Open Access Journals (Sweden)

    Patrizia Frontera

    2017-02-01

    Full Text Available CO2 methanation is a well-known reaction that is of interest as a capture and storage (CCS process and as a renewable energy storage system based on a power-to-gas conversion process by substitute or synthetic natural gas (SNG production. Integrating water electrolysis and CO2 methanation is a highly effective way to store energy produced by renewables sources. The conversion of electricity into methane takes place via two steps: hydrogen is produced by electrolysis and converted to methane by CO2 methanation. The effectiveness and efficiency of power-to-gas plants strongly depend on the CO2 methanation process. For this reason, research on CO2 methanation has intensified over the last 10 years. The rise of active, selective, and stable catalysts is the core of the CO2 methanation process. Novel, heterogeneous catalysts have been tested and tuned such that the CO2 methanation process increases their productivity. The present work aims to give a critical overview of CO2 methanation catalyst production and research carried out in the last 50 years. The fundamentals of reaction mechanism, catalyst deactivation, and catalyst promoters, as well as a discussion of current and future developments in CO2 methanation, are also included.

  13. Cerebrovascular CO2 reactivity in normotensive and hypertensive man

    DEFF Research Database (Denmark)

    Tominaga, S; Strandgaard, S; Uemura, K

    1976-01-01

    Cerebrovascular reactivity to CO2 inhalation and voluntary hyperventilation was studied in seven normotensive subjects and nine hypertensive patients without clinical or angiographical signs of arteriosclerosis. Cerebral blood flow (CBF) was measured by the intracarotid 133Xe clearance method...... and calculated as the initial slope index. Three to five CBF measurements were made in each patient in the PaCO2 range of 20 to 55 mm Hg. No difference was observed in reactivity between hypertensive and normotensive patients, either during CO2 inhalation or during hyperventilation. The shape of the CBF:PaCO2...

  14. Reducing of CO2 emissions and its depositing into underground

    Directory of Open Access Journals (Sweden)

    Jaroslava Koudelková

    2005-11-01

    Full Text Available Increasing CO2 emissions caused especially by the combustion of fossil fuels rises a question of how this can be problem solved in the long term. There is several solutions which differ technically and financially. This paper deals with the CO2 capture from combustion processes or power plant processes, (CO2 can be captured from the flue gas, after combustion in oxygen and recirculated flue gas or from a synthesis gas before combustion. This paper presents possibilities of CO2 storagex captured in this way into underground (deep ocean, oil and gas fields, coal bed, aquifers.

  15. Enhanced Oil Recovery with CO2 Capture and Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Andrei, Maria; De Simoni, Michela; Delbianco, Alberto; Cazzani, Piero; Zanibelli, Laura

    2010-09-15

    This paper presents the results of a feasibility study aimed at extending the production life of a small oilfield in Italy through EOR, employing the CO2 captured from the flue gas streams of the refinery nearby. The EOR operation allows the recovery of additional reserves while a consistent amount of the CO2 injected remains permanently stored into the reservoir. The screening process selection for EOR-CO2 and the main elements of the pilot project for the proper upstream-downstream integration will be described. Evaluation of EOR-CO2 extension to other oilfields and its effect on oil production and project's economics will be reported.

  16. A Global Perspective of Atmospheric CO2 Concentrations

    Science.gov (United States)

    Putman, William M.; Ott, Lesley; Darmenov, Anton; daSilva, Arlindo

    2016-01-01

    Carbon dioxide (CO2) is the most important greenhouse gas affected by human activity. About half of the CO2 emitted from fossil fuel combustion remains in the atmosphere, contributing to rising temperatures, while the other half is absorbed by natural land and ocean carbon reservoirs. Despite the importance of CO2, many questions remain regarding the processes that control these fluxes and how they may change in response to a changing climate. The Orbiting Carbon Observatory-2 (OCO-2), launched on July 2, 2014, is NASA's first satellite mission designed to provide the global view of atmospheric CO2 needed to better understand both human emissions and natural fluxes. This visualization shows how column CO2 mixing ratio, the quantity observed by OCO-2, varies throughout the year. By observing spatial and temporal gradients in CO2 like those shown, OCO-2 data will improve our understanding of carbon flux estimates. But, CO2 observations can't do that alone. This visualization also shows that column CO2 mixing ratios are strongly affected by large-scale weather systems. In order to fully understand carbon flux processes, OCO-2 observations and atmospheric models will work closely together to determine when and where observed CO2 came from. Together, the combination of high-resolution data and models will guide climate models towards more reliable predictions of future conditions.

  17. Fabry-Perot Interferometer for Column CO2: Airborne

    Science.gov (United States)

    Kawa, S. R.; Heaps, W. S.; Mao, J.; Andrews, A. E.; Burris, J. F.; Miodek, M.; Georgieva, E.

    2002-01-01

    Global atmospheric CO2 measurements are essential to resolving significant discrepancies in our understanding of the global carbon budget and, hence, humankind's role in global climate change. The science measurement requirements for CO2 are, however, extremely demanding (precision approximately 0.3%). We are developing a novel application of a Fabry-Perot interferometer to detect spectral absorption of reflected sunlight by CO2 and O2 in the atmosphere that should be able to achieve sufficient sensitivity and signal-to-noise to measure column CO2 at the target specification. We are currently constructing a prototype instrument for deployment on aircraft. The aircraft version will measure total column CO2 and CO2 below the aircraft as well as O2, which allows normalization of CO2 column amounts for varying surface height and pressure. This instrument will be a valuable asset in carbon budget field studies as well as a useful tool for evaluating existing and future space-based CO2 measurements. We will present the instrument concept, sensitivity calculations, and the results of testing a bench system in the laboratory and outdoors on the ground. We will also discuss our plan for deployment on the aircraft and potential flight applications to the CO2 budget problem.

  18. Electrochemical CO2 concentration for the Space Station Program

    Science.gov (United States)

    Lance, N.; Schwartz, M.; Boyda, R. B.

    1985-01-01

    Under the sponsorship of NASA, Electrochemical Carbon Dioxide (CO2) Concentration EDC technology has been developed that removes CO2 continuously or cyclically from low CO2 partial pressure (400 Pa) atmospheres with the performance and operating characteristics required for Space Station applications. The most recent advancement of this technology is the development of an advanced preprototype subsystem, the CS-3A, to remove the metabolic CO2 produced by three persons from the projected Space Station atmosphere. This paper provides an overview of EDC technology, shows how it is ideally suited for Space Station application, and presents technology enhancements that will be demonstrated by the CS-3A subsystem development program.

  19. Positive feedback between increasing atmospheric CO2 and ecosystem productivity

    Science.gov (United States)

    Gelfand, I.; Hamilton, S. K.; Robertson, G. P.

    2009-12-01

    Increasing atmospheric CO2 will likely affect both the hydrologic cycle and ecosystem productivity. Current assumptions that increasing CO2 will lead to increased ecosystem productivity and plant water use efficiency (WUE) are driving optimistic predictions of higher crop yields as well as greater availability of freshwater resources due to a decrease in evapotranspiration. The plant physiological response that drives these effects is believed to be an increase in carbon uptake either by (a) stronger CO2 gradient between the stomata and the atmosphere, or by (b) reduced CO2 limitation of enzymatic carboxylation within the leaf. The (a) scenario will lead to increased water use efficiency (WUE) in plants. However, evidence for increased WUE is mostly based on modeling studies, and experiments producing a short duration or step-wise increase in CO2 concentration (e.g. free-air CO2 enrichment). We hypothesize that the increase in atmospheric CO2 concentration is having a positive effect on ecosystem productivity and WUE. To investigate this hypothesis, we analyzed meteorological, ANPP, and soil CO2 flux datasets together with carbon isotopic ratio (13C/12C) of archived plant samples from the long term ecological research (LTER) program at Kellogg Biological Station. The datasets were collected between 1989 and 2007 (corresponding to an increase in atmospheric CO2 concentration of ~33 ppmv at Mauna Loa). Wheat (Triticum aestivum) samples taken from 1989 and 2007 show a significant decrease in the C isotope discrimination factor (Δ) over time. Stomatal conductance is directly related to Δ, and thus Δ is inversely related to plant intrinsic WUE (iWUE). Historical changes in the 13C/12C ratio (δ13C) in samples of a perennial forb, Canada goldenrod (Solidago canadensis), taken from adjacent successional fields, indicate changes in Δ upon uptake of CO2 as well. These temporal trends in Δ suggest a positive feedback between the increasing CO2 concentration in the

  20. CO2 Sink/Source in the Indonesian Seas

    KAUST Repository

    Kartadikaria, Aditya R.

    2015-04-01

    Two distinct CO2 sink/source characteristics appeared from the compiled observed data 1984-2013 in the tropical Indonesian seas. The western part persistently emits CO2 to the atmosphere, while the eastern is rather dynamic which emits and absorbs smaller amount of CO2 to and from atmosphere, respectively. The segregation is proximal to the virtual Wallace line, where in the continental shelf is located. Lower salinity and higher silicate condition in the western part influenced the higher pCO2 condition in Java Sea. Temperature is found to have a limited influence to control different characteristic in the west and east, but SST change of 2.0 0C during La Ninã condition effectively reduced the source amount of CO2 by 50% compared to Normal year condition. Yet, during La Ninã, higher wind speed increases CO2 flux twice compared to Normal year. In the continental shelf area where CO2 sink area is found, 29 years data showed that pCO2 trend is increasing ±0.6-3.8 μatm/year. From this study, the overall areas have a significant source of CO2 of approximately 10 - 24 μatm.

  1. An advanced analytical solution for pressure build-up during CO2 injection into infinite saline aquifers: The role of compressibility

    Science.gov (United States)

    Wu, Haiqing; Bai, Bing; Li, Xiaochun

    2018-02-01

    Existing analytical or approximate solutions that are appropriate for describing the migration mechanics of CO2 and the evolution of fluid pressure in reservoirs do not consider the high compressibility of CO2, which reduces their calculation accuracy and application value. Therefore, this work first derives a new governing equation that represents the movement of complex fluids in reservoirs, based on the equation of continuity and the generalized Darcy's law. A more rigorous definition of the coefficient of compressibility of fluid is then presented, and a power function model (PFM) that characterizes the relationship between the physical properties of CO2 and the pressure is derived. Meanwhile, to avoid the difficulty of determining the saturation of fluids, a method that directly assumes the average relative permeability of each fluid phase in different fluid domains is proposed, based on the theory of gradual change. An advanced analytical solution is obtained that includes both the partial miscibility and the compressibility of CO2 and brine in evaluating the evolution of fluid pressure by integrating within different regions. Finally, two typical sample analyses are used to verify the reliability, improved nature and universality of this new analytical solution. Based on the physical characteristics and the results calculated for the examples, this work elaborates the concept and basis of partitioning for use in further work.

  2. Direct Air Capture of CO2 with an Amine Resin: A Molecular Modeling Study of the CO2 Capturing Process.

    Science.gov (United States)

    Buijs, Wim; de Flart, Stijn

    2017-11-01

    Several reactions, known from other amine systems for CO2 capture, have been proposed for Lewatit R VP OC 1065. The aim of this molecular modeling study is to elucidate the CO2 capture process: the physisorption process prior to the CO2-capture and the reactions. Molecular modeling yields that the resin has a structure with benzyl amine groups on alternating positions in close vicinity of each other. Based on this structure, the preferred adsorption mode of CO2 and H2O was established. Next, using standard Density Functional Theory two catalytic reactions responsible for the actual CO2 capture were identified: direct amine and amine-H2O catalyzed formation of carbamic acid. The latter is a new type of catalysis. Other reactions are unlikely. Quantitative verification of the molecular modeling results with known experimental CO2 adsorption isotherms, applying a dual site Langmuir adsorption isotherm model, further supports all results of this molecular modeling study.

  3. Comparison of Surface and Column Variations of CO2 Over Urban Areas for Future Active Remote CO2 Sensors

    Science.gov (United States)

    Choi, Yonghoon; Yang, Melissa; Kooi, Susan; Browell, Edward

    2015-01-01

    High resolution in-situ CO2 measurements were recorded onboard the NASA P-3B during the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) Field Campaign, to investigate the ability of space-based observations to accurately assess near surface conditions related to air quality. This campaign includes, Washington DC/Baltimore, MD (July 2011), San Joaquin Valley, CA (January - February 2013), Houston, TX (September 2013), and Denver, CO (July-August 2014). Each of these campaigns consisted of missed approaches and approximately two hundred vertical soundings of CO2 within the lower troposphere (surface to about 5 km). In this study, surface (0 - 1 km) and column-averaged (0 - 3.5 km) CO2 mixing ratio values from the vertical soundings in the four geographically different urban areas are used to investigate the temporal and spatial variability of CO2 within the different urban atmospheric emission environments. Tracers such as CO, CH2O, NOx, and NMHCs are used to identify the source of CO2 variations in the urban sites. Additionally, we apply nominal CO2 column weighting functions for potential future active remote CO2 sensors operating in the 1.57-microns and 2.05-microns measurement regions to convert the in situ CO2 vertical mixing ratio profiles to variations in CO2 column optical depths, which is what the active remote sensors actually measure. Using statistics calculated from the optical depths at each urban site measured during the DISCOVER-AQ field campaign and for each nominal weighting function, we investigate the natural variability of CO2 columns in the lower troposphere; relate the CO2 column variability to the urban surface emissions; and show the measurement requirements for the future ASCENDS (Active Sensing of CO2 Emissions over Nights, Days, and Seasons) in the continental U.S. urban areas.

  4. Selected Issues on CO2 in Compression Systems

    Energy Technology Data Exchange (ETDEWEB)

    Aarlien, R.

    2004-05-15

    Carbon Dioxide (CO2) has shown promising results as an alternative working fluid compared to the CFCs, HFCs and HCFCs. CO2 provides an environmental friendly alternative in a number of heat pump applications, in automobile air conditioning, and as a secondary fluid in refrigeration systems. The physical and the thermodynamic properties of CO2 differ considerably from the more conventional working fluids and offer new possibilities as well as design challenges for systems and components. On this background IEA Heat Pump Programme's Annex 27 was established. The main objective of the Annex has been to bring the CO2 heat pump technology closer to commercialization, by addressing critical issues of both basic and applied character. The scope of the work under this Annex includes compression heat pump, refrigeration and air-conditioning systems and components, with the main emphasis on heat pumps, using CO2 as working fluid. The term 'compression heat pump' covers vapor compression circuits with phase change. The term 'system' includes all the components used in a heating/cooling system from the heat pump to the inside unit, controls included. Results from 12 different research projects together with an extensive literature survey are presented. The projects are carried out as independent research projects, and the findings and the results are the sole responsibility of the authors. The following projects are presented: 1) Feasibility of transcritical CO2 systems for mobile space conditioning applications. 2) Use of CO2- and propane thermosyphons in combination with compact cooler in domestic freeze. 3) Heat transfer of carbon dioxide in an evaporator. 4) Correlating the heat transfer coefficient during in-tube cooling of turbulent supercritical CO2. 5) Heat transfer and pressure drop characteristics of super-critical CO2 in microchannel tubes under cooling. 6) Flow vaporization of CO2 in microchannel tubes. 7) Two-phase flow patterns during

  5. Chemical reactions occurring during direct solar reduction of CO2.

    Science.gov (United States)

    Lyma, J L; Jensen, R J

    2001-09-28

    At high temperatures carbon dioxide may absorb solar radiation and react to form carbon monoxide and molecular oxygen. The CO, so produced, may be converted by well-established means to a combustible fuel, such as methanol. We intend to make a future demonstration of the solar reduction of CO2 based on these processes. This paper, however, addresses only the problem of preserving, or even enhancing, the initial photolytic CO by quenching the hot gas with colder H2O or CO2. We present model calculations with a reaction mechanism used extensively in other calculations. If a CO2 gas stream is heated and photolyzed by intense solar radiation and then allowed to cool slowly, it will react back to the initial CO2 by a series of elementary chemical reactions. The back reaction to CO2 can be terminated with the rapid addition of CO2, water, or a mixture. Calculations show that a three-fold quench with pure CO2 will stop the reactions and preserve over 90% of the initial photolytic CO. We find that water has one of two effects. It can either increase the CO level, or it can catalyze the recombination of O and CO to CO2. The gas temperature is the determining factor. If the quench gas is not sufficient to keep the temperature below approximately 1100 K, a chain-branching reaction dominates and the reaction to CO2 occurs. If the temperature stays below that level a chain terminating reaction dominates and the CO is increased. The former case occurs below approximately a fourfold quench with a water/CO2 mixture. The later case occurs when the quench is greater than fourfold. We conclude that CO2, H2O, or a mixture may quench the hot gas stream photolyzed by solar radiation and preserve the photolytic CO.

  6. Crystal structures and dynamical properties of dense CO2

    Science.gov (United States)

    Yong, Xue; Liu, Hanyu; Wu, Min; Yao, Yansun; Tse, John S.; Dias, Ranga; Yoo, Choong-Shik

    2016-01-01

    Structural polymorphism in dense carbon dioxide (CO2) has attracted significant attention in high-pressure physics and chemistry for the past two decades. Here, we have performed high-pressure experiments and first-principles theoretical calculations to investigate the stability, structure, and dynamical properties of dense CO2. We found evidence that CO2-V with the 4-coordinated extended structure can be quenched to ambient pressure below 200 K—the melting temperature of CO2-I. CO2-V is a fully coordinated structure formed from a molecular solid at high pressure and recovered at ambient pressure. Apart from confirming the metastability of CO2-V (I-42d) at ambient pressure at low temperature, results of ab initio molecular dynamics and metadynamics (MD) simulations provided insights into the transformation processes and structural relationship from the molecular to the extended phases. In addition, the simulation also predicted a phase V′(Pna21) in the stability region of CO2-V with a diffraction pattern similar to that previously assigned to the CO2-V (P212121) structure. Both CO2-V and -V′ are predicted to be recoverable and hard with a Vicker hardness of ∼20 GPa. Significantly, MD simulations found that the CO2 in phase IV exhibits large-amplitude bending motions at finite temperatures and high pressures. This finding helps to explain the discrepancy between earlier predicted static structures and experiments. MD simulations clearly indicate temperature effects are critical to understanding the high-pressure behaviors of dense CO2 structures—highlighting the significance of chemical kinetics associated with the transformations. PMID:27647887

  7. Simulasi Numeris Karakteristik Pembakaran CH4/CO2/Udara dan CH4/CO2/O2 pada Counterflow Premixed Burner

    Directory of Open Access Journals (Sweden)

    Hangga Wicaksono

    2017-08-01

    Full Text Available The high amount of CO2 produced in a conventional biogas reactor needs to be considered. A further analysis is needed in order to investigate the effect of CO2 addition especially in thermal and chemical kinetics aspect. This numerical study has been held to analyze the effect of CO2 in CH4/CO2/O­2 and CH4/CO2/Air premixed combustion. In this study one dimensional analisys in a counterflow burner has been performed. The volume fraction of CO2 used in this study was 0%-40% from CH4’s volume fraction, according to the amount of CO2 in general phenomenon. Based on the flammability limits data, the volume fraction of CH4 used was 5-61% in O2 environment and 5-15% in air environment. The results showed a decreasing temperature along with the increasing percentage of CO2 in each mixtures, but the effect was quite smaller especially in stoichiometric and lean mixture. CO2 could affects thermally (by absorbing heat due to its high Cp and also made the production of unburnt fuel species such as CO relatively higher.

  8. CO2 footprint 2008 District Oud-Zuid, Amsterdam, Netherlands; CO2-voetafdruk 2008 Stadsdeel Oud-Zuid [Amsterdam

    Energy Technology Data Exchange (ETDEWEB)

    Hanekamp, E.; Van Merksteijn, C. [Partners for Innovation, Amsterdam (Netherlands)

    2009-06-15

    The district 'Oud-Zuid' in Amsterdam, Netherlands, plans to become CO2 neutral in 2015. For this purpose, the CO2 footprint of the district is determined and a plan of action developed. By means of scenarios, the district council can make choices for climate investments [Dutch] Stadsdeel Oud-Zuid van de gemeente Amsterdam wil CO2-neutraal zijn in 2015. Daartoe is de CO2-voetafdruk van Oud-Zuid bepaald en een plan van aanpak uitgewerkt. Met behulp van scenario's zal de stadsdeelraad keuzes kunnen maken over haar klimaatinvesteringen.

  9. Serpentine diffusion trajectories and the Ouzo effect in partially miscible ternary liquid mixtures

    NARCIS (Netherlands)

    Krishna, R.

    2015-01-01

    This work investigates the transient equilibration process when partially miscible ternary liquid mixtures of two different compositions are brought into contact with each other. Diffusional coupling effects are shown to become increasingly significant as the mixture compositions approach the

  10. MISCIBILITY, SOLUBILITY, AND VISCOSITY MEASUREMENTS FOR R-236EA WITH POTENTIAL LUBRICANTS

    Science.gov (United States)

    The report gives results of miscibility, solubility, and viscosity measurements of refrigerant R-236ea with three potential lubricants. (NOTE: The data were needed to determine the suitability of refrigerant/lubricant combinations for use in refrigeration systems.) The lubricants...

  11. Influence of travel behavior on global CO2 emissions

    NARCIS (Netherlands)

    Girod, B.; Vuuren, D.P. van; Vries, B. de

    2013-01-01

    Travel demand is rising steeply and its contribution to global CO2 emissions is increasing. Different studies have shown possible mitigation through technological options, but so far few studies have evaluated the implications of changing travel behavior on global travel demand, energy use and CO2

  12. Mechanochemical synthesis and characterization of pure Co2B ...

    Indian Academy of Sciences (India)

    Cobalt boride (Co 2 B) is a significant transition metal boride having a wide range of usage area due to its high oxidation, abrasion and corrosion resistance as well as its superior electrochemical, magnetic and anisotropicproperties. In this study, pure Co2B nanocrystals were synthesized with Co, B 2 O 3 and Mg as starting ...

  13. Selective Electrocatalytic CO2 Conversion on Metal Surfaces

    NARCIS (Netherlands)

    Ma, M.

    2017-01-01

    The electrocatalytic conversion of CO2 into fuel and valuable chemicals by coupling with a renewable electricity source is a promising strategy for closing the anthropogenic carbon cycle. The critical step for achieving this practical CO2 utilization is to find a suitable electrocatalyst that is

  14. CO2 sorption by supported amino acid ionic liquids

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention concerns the absorption and desorption behaviour of carbon dioxide (CO2) using ionic liquids derived from amino acids adsorbed on porous carrier materials.......The present invention concerns the absorption and desorption behaviour of carbon dioxide (CO2) using ionic liquids derived from amino acids adsorbed on porous carrier materials....

  15. CO2 emissions from soil incubated with sugarcane straw and ...

    African Journals Online (AJOL)

    SAM

    2014-08-13

    CO2 until the 79th. DAI) and initial accumulated respiration (Σ-CO2 until the 5th DAI). Analytical procedures. At the 80th DAI, the incubated soils were sieved (2 mm opening) to remove the remaining crop residue from the soil.

  16. AMESCO General Study Environmental Impacts CO2-storage. Public summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-15

    The AMESCO study aims to supply environmental background information on CO2-storage in the Netherlands for the broad group of initiators and other stakeholders. By bringing together the information from the scientific world, companies and authorities and by analysing relevant policies it is intended to eludicate: which are the possible environmental effects of CO2-injection and storage; which are the possibilities for risk reduction or mitigation; which existing legislation is of relevance for CO2-storage in the deep surface; where are the gaps in knowledge and legislation with regard to CO2-storage. The report produced during the AMESCO study should be seen as a broad answer to the four questions mentioned above. In specific projects the report can be used as a background document during permitting procedures. This background information has to be supplemented with location specific information. The report can also be used as input for an environmental impact assessment (EIA). For practical reasons the AMESCO study was performed with the following scope limitations: (1) Focus on potential impacts and risks resulting from the storage of CO2; (2) Only consider CO2-storage in gas reservoirs; (3) Only consider onshore projects; (4) Only consider permanent storage; (5) Consider alternative options for CO2-storage in gas reservoirs; but not other forms of CO2-emission reduction. The scope is limited to depleted gas fields, from which the economically recoverable resources have already been taken.

  17. New methodologies for integrating algae with CO2 capture

    NARCIS (Netherlands)

    Hernandez Mireles, I.; Stel, R.W. van der; Goetheer, E.L.V.

    2014-01-01

    It is generally recognized, that algae could be an interesting option for reducing CO2 emissions. Based on light and CO2, algae can be used for the production various economically interesting products. Current algae cultivation techniques, however, still present a number of limitations. Efficient

  18. Costs, safety and uncertainties of CO2 infrastructure development

    NARCIS (Netherlands)

    Knoope, M.M.J.|info:eu-repo/dai/nl/364248149

    2015-01-01

    To avoid drastic climate change, strong reductions in CO2 emissions are required. Carbon capture and storage (CCS) is a potential mitigation measure. With CCS, CO2 from industrial and energy related sources is captured from flue gases and subsequently transported with pipelines and / or ships to

  19. CO2-Philic polymer membrane with extremely high separation performance

    KAUST Repository

    Yave, Wilfredo

    2010-01-12

    Polymeric membranes are attractive for CO2 separation and concentration from different gas streams because of their versatility and energy efficiency; they can compete with, and they may even replace, traditional absorption processes. Here we describe a simple and powerful method for developing nanostructured and CO2-philic polymer membranes for CO2 separation. A poly(ethylene oxide)-poly(butylene terephthalate) multiblock copolymer is used as membrane material. Smart additives such as polyethylene glycol dibutyl ether are incorporated as spacers or fillers for producing nanostructured materials. The addition of these specific additives produces CO2-philic membranes and increases the CO2 permeability (750 barrer) up to five-fold without the loss of selectivity. The membranes present outstanding performance for CO2 separation, and the measured CO2 flux is extremely high ( > 2 m3 m -2 h-1 bar-1) with selectivity over H2 and N2 of 10 and 40, respectively, making them attractive for CO 2 capture. © 2009 American Chemical Society.

  20. CO2 dissolution and its impact on reservoir pressure behavior

    NARCIS (Netherlands)

    Peters, E.; Egberts, P.J.P.; Loeve, D.; Hofstee, C.

    2015-01-01

    Geological storage of CO2 in large, saline aquifers needs to be monitored for safety purposes. In particular the observation of the pressure behavior of a storage site is relevant for the indication of CO2 leakage. However, interpretation of observed pressure is not straightforward in these systems,

  1. A Quantitative Investigation of CO2 Sequestration by Mineral Carbonation

    CERN Document Server

    Mohammad, Muneer

    2015-01-01

    Anthropogenic activities have led to a substantial increase in carbon dioxide (CO2), a greenhouse gas (GHG), contributing to heightened concerns of global warming. In the last decade alone CO2 emissions increased by 2.0 ppm/yr. globally. In the year 2009, United States and China contributed up to 43.4% of global CO2 emissions. CO2 capture and sequestration have been recognized as promising solutions to mitigate CO2 emissions from fossil fuel based power plants. Typical techniques for carbon capture include post-combustion capture, pre-combustion capture and oxy-combustion capture, which are under active research globally. Mineral carbonation has been investigated as a suitable technique for long term storage of CO2. Sequestration is a highly energy intensive process and the additional energy is typically supplied by the power plant itself. This leads to a reduction in net amount of CO2 captured because of extra CO2 emitted. This paper presents a quantitative analysis of the energy consumption during sequestra...

  2. Target atmospheric CO2: Where should humanity aim?

    CERN Document Server

    Hansen, J; Kharecha, P; Beerling, D; Masson-Delmotte, V; Pagani, M; Raymo, M; Royer, D L; Zachos, J C

    2008-01-01

    Paleoclimate data show that climate sensitivity is ~3 deg-C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6 deg-C for doubled CO2 for the range of climate states between glacial conditions and ice-free Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425 +/- 75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practice...

  3. CO2-emissiehandel in 2020 : betekenis voor de Nederlandse glastuinbouw

    NARCIS (Netherlands)

    Bunte, F.H.J.; Dijkxhoorn, Y.

    2009-01-01

    Het rapport bepaalt de impact van de EU-richtlijn voor de handel in CO2-emissierechten voor de Nederlandse glastuinbouw. Het rapport berekent de kosten die de richtlijn met zich meebrengt voor de sector en bepaalt het effect op de CO2- uitstoot door de sector. Verder bepaalt het rapport het effect

  4. CO2 as a smart gelator for Pluronic aqueous solutions.

    Science.gov (United States)

    Liu, Chengcheng; Mei, Qingqing; Zhang, Jianling; Kang, Xinchen; Peng, Li; Han, Buxing; Xue, Zhimin; Sang, Xinxin; Yang, Xiaogan; Wu, Zhonghua; Li, Zhihong; Mo, Guang

    2014-11-25

    It was found that CO2 could induce the gelation of Pluronic aqueous solutions, during which the microstructure of the solution transforms from randomly dispersed spherical micelles to cubic close packed micelles. The gelation switched by compressed CO2 has many advantages and can be applied in the synthesis of porous materials.

  5. Resolving CO2 and methane hydrate formation kinetics

    NARCIS (Netherlands)

    Golombok, M.; Ineke, E.; Luzardo, J.C.R.; He, Y.Y.; Zitha, P.

    2008-01-01

    We analyse the kinetics of CO2 and methane hydrate formation. The characteristic formation times are associated with different steps of the formation process. Conditions for minimising these rate times are identified while maintaining a regime where CO2 hydrate is formed and methane remains

  6. Vesicularity and CO2 in mid-ocean ridge basalt

    Science.gov (United States)

    Moore, J.G.

    1979-01-01

    Vesicles and included CO2are enriched in deep-sea basalts that are also enriched in light rare earth and incompatible elements. This enrichment probably results from a unique deep mantle origin of such melts but may have been modified by CO2 bubbles rising in shallow magma chambers. ?? 1979 Nature Publishing Group.

  7. Geothermal energy combined with CO2 sequestration : An additional benefit

    NARCIS (Netherlands)

    Salimi, H.; Wolf, K.H.A.A.; Bruining, J.

    2012-01-01

    In this transition period from a fossil-fuel based society to a sustainable-energy society, it is expected that CO2 capture and subsequent sequestration in geological formations plays a major role in reducing greenhouse gas emissions. An alternative for CO2 emission reduction is to partially replace

  8. Adsorption and Dissociation of CO2 on Ru

    NARCIS (Netherlands)

    Pachecka, Malgorzata; Sturm, Jacobus Marinus; Lee, Christopher James; Bijkerk, Frederik

    2017-01-01

    The adsorption and dissociation of carbon dioxide on a Ru(0001) single crystal surface was investigated by reflection–absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption (TPD) spectroscopy for CO2 adsorbed at 85 K. RAIRS spectroscopy shows that the adsorption of CO2 on a

  9. Fractional CO2 laser resurfacing for atrophic acne scars

    DEFF Research Database (Denmark)

    Hedelund, Lene; Haak, Christina Skovbølling; Togsverd-Bo, Katrine

    2012-01-01

    The treatment of acne scars with fractional CO(2) lasers is gaining increasing impact, but has so far not been compared side-by-side to untreated control skin.......The treatment of acne scars with fractional CO(2) lasers is gaining increasing impact, but has so far not been compared side-by-side to untreated control skin....

  10. Extra CO2 kan nuttig zijn bij snij-anthurium

    NARCIS (Netherlands)

    Garcia Victoria, N.

    2011-01-01

    Bij de snij-anthurium Midori zijn in een proef van WUR Glastuinbouw 10% meer bloemen geoogst door extra CO2 toe te dienen. Tropical reageerde met grotere bloemdiameters. Grotere bloemen brengen meestal meer op. Extra CO2 is dus voor deze cultivars economisch interessant.

  11. A role for atmospheric CO2 in preindustrial climate forcing

    NARCIS (Netherlands)

    Hoof, T.B. van; Wagner-Cremer, F.; Kürschner, W.M.; Visscher, H.

    2008-01-01

    Complementary to measurements in Antarctic ice cores, stomatal frequency analysis of leaves of land plants preserved in peat and lake deposits can provide a proxy record of preindustrial atmospheric CO2 concentration. CO2 trends based on leaf remains of Quercus robur (English oak) from the

  12. Transient nature of CO2 fertilization in arctic tundra

    Science.gov (United States)

    Walter C. Oechel; Sid Cowles; Nancy Grulke; Steven J. Hastings; Bill Lawrence; Tom Prudhomme; George Riechers; Boyd Strain; David Tissue; George. Vourlitis

    1994-01-01

    There has been much debate about the effect of increased atmospheric CO2 concentrations on plant net primary production1,3 and on net ecosystem CO2 flux3–10. Apparently conflicting experimental findings could be the result of differences in genetic potential11–15...

  13. Ni–Fe–S Cubanes in CO2 Reduction Electrocatalysis

    DEFF Research Database (Denmark)

    Varley, J. B.; Hansen, H. A.; Ammitzbøll, Nadia Luciw

    2013-01-01

    In this work, we perform extensive mechanistic studies of CO2 (electro)reduction by analogs to the active sites of carbon monoxide dehydrogenase (CODH) enzymes. We explore structure–property relationships for different cluster compositions and interpret the results with a model for CO2...

  14. Hydrogel-based sensor for CO2 measurements

    NARCIS (Netherlands)

    Herber, S.; Olthuis, Wouter; Bergveld, Piet; van den Berg, Albert

    2004-01-01

    A hydrogel-based sensor is presented for CO2 measurements. The sensor consists of a pressure sensor and porous silicon cover. A pH-sensitive hydrogel is confined between the two parts. Furthermore the porous cover contains a bicarbonate solution and a gaspermeable membrane. CO2 reacts with the

  15. Aquaporins and membrane diffusion of CO2 in living organisms.

    Science.gov (United States)

    Kaldenhoff, Ralf; Kai, Lei; Uehlein, Norbert

    2014-05-01

    Determination of CO2 diffusion rates in living cells revealed inconsistencies with existing models about the mechanisms of membrane gas transport. Mainly, these discrepancies exist in the determined CO2 diffusion rates of bio-membranes, which were orders of magnitudes below those for pure lipid bilayers or theoretical considerations as well as in the observation that membrane insertion of specific aquaporins was rescuing high CO2 transport rates. This effect was confirmed by functional aquaporin protein analysis in heterologous expression systems as well as in bacteria, plants and partly in mammals. This review summarizes the arguments in favor of and against aquaporin facilitated membrane diffusion of CO2 and reports about its importance for the physiology of living organisms. Most likely, the aquaporin tetramer forming an additional fifth pore is required for CO2 diffusion facilitation. Aquaporin tetramer formation, membrane integration and disintegration could provide a mechanism for regulation of cellular CO2 exchange. The physiological importance of aquaporin mediated CO2 membrane diffusion could be shown for plants and cyanobacteria and partly for mammals. Taking the mentioned results into account, consequences for our current picture of cell membrane transport emerge. It appears that in some or many instances, membranes might not be as permeable as it was suggested by current bio-membrane models, opening an additional way of controlling the cellular influx or efflux of volatile substances like CO2. This article is part of a Special Issue entitled Aquaporins. © 2013.

  16. A 10 cm aperture, high quality TEA CO2 laser

    NARCIS (Netherlands)

    Ernst, G.J.

    1982-01-01

    Experiments have been performed on a corona preionization type 10 cm aperture TEA CO2 laser. For a CO2:N2:He=1: 1: 7: mixture an output energy of 34 joule per liter and for a 1 : 1 : 10 mixture 40 joule per liter could be obtained. The overall efficiency is about 18%. The time behaviour of the

  17. CO2 absorption characteristics of monoethanol amine aqueous solution and recovery of CO2 from marine engine exhaust; Monoethanol amine suiyoeki no CO2 kyushu tokusei to hakuyo kikan no CO2 kaishu

    Energy Technology Data Exchange (ETDEWEB)

    Ikame, M.; Suga, S.; Hiraoka, K.; Kumakura, T. [Ship Research Inst., Tokyo (Japan)

    1994-04-13

    Investigations were made on characteristics of CO2 absorption into monoethanol amine aqueous solution under normal pressure as a method of recovering CO2, the CO2 concentration and effect of the accompanying gases. Furthermore, assuming a large marine diesel engine using methanol as a fuel, the experimental result was used to discuss a size of the CO2 absorbing device. Assuming exhaust gases from a methanol-fueled diesel engine and steam reformed gas of methanol, from which CO2 is to be recovered, the experiment used two kinds of accompanying gases, N2 and H2, and the CO2 concentrations of 5% to 25% by volume. The relationship between the CO2 material balance and the substance movement between gas and liquid based on the double boundary film theory was put into order to derive an experiment equation. This equation was capable of expression with an error of less than {plus_minus}35%. This paper indicates by using the experimental result a method to derive the size of an absorbing and filling layer for CO2 in exhaust gases from a methanol fueled marine diesel engine. Given an example, the volume of the filling layer in the absorption column is required to be about 12% of the engine volume of 770m{sup 3}, and the absorption flow rate to be 65.4kg/s. 4 refs., 6 figs., 1 tab.

  18. Tuning of CO2 Reduction Selectivity on Metal Electrocatalysts.

    Science.gov (United States)

    Wang, Yuhang; Liu, Junlang; Wang, Yifei; Al-Enizi, Abdullah M; Zheng, Gengfeng

    2017-11-01

    Climate change, caused by heavy CO2 emissions, is driving new demands to alleviate the rising concentration of atmospheric CO2 levels. Enlightened by the photosynthesis of green plants, photo(electro)chemical catalysis of CO2 reduction, also known as artificial photosynthesis, is emerged as a promising candidate to address these demands and is widely investigated during the past decade. Among various artificial photosynthetic systems, solar-driven electrochemical CO2 reduction is widely recognized to possess high efficiencies and potentials for practical application. The efficient and selective electroreduction of CO2 is the key to the overall solar-to-chemical efficiency of artificial photosynthesis. Recent studies show that various metallic materials possess the capability to play as electrocatalysts for CO2 reduction. In order to achieve high selectivity for CO2 reduction products, various efforts are made including studies on electrolytes, crystal facets, oxide-derived catalysts, electronic and geometric structures, nanostructures, and mesoscale phenomena. In this Review, these methods for tuning the selectivity of CO2 electrochemical reduction of metallic catalysts are summarized. The challenges and perspectives in this field are also discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. CO2 reduction strategies for the Northern Netherlands

    NARCIS (Netherlands)

    Benders, Rene; Moll, Henk; Noorman, Klaas Jan; Wiersma, Gerwin

    2011-01-01

    The concern about global warming initiated ambitious CO2 reduction goals in cities and regions in the Netherlands. This article describes a study of such a local initiative for the Northern Netherlands. The research aimed to develop CO2 reduction scenarios for 2035 with national and international

  20. Enhanced cerebral CO2 reactivity during strenuous exercise in man

    DEFF Research Database (Denmark)

    Rasmussen, Peter; Stie, Henrik; Nielsen, Bodil

    2006-01-01

    subjects by the administration of CO(2) as well as by voluntary hypo- and hyperventilation at rest and during exercise with and without hyperthermia. At rest, P(a)CO(2) was 5.1 +/- 0.2 kPa (mean +/- SEM) and MCA V(mean) 50.7 +/- 3.8 cm s(-1) and the relationship between MCA V(mean) and P(a)CO(2 )was linear...... (double-log slope 1.1 +/- 0.1). However, the relationship became curvilinear during exercise (slope 1.8 +/- 0.1; P exercise with hyperthermia (slope 2.3 +/- 0.3; P exercise). Accordingly, the cerebral CO(2) reactivity increased from 30.5 +/- 2.7% kPa(-1...... be accounted for by the reduction in the arterial CO(2) tension (P(a)CO(2)). This study evaluated whether the apparently large reduction in MCA V(mean) at the end of exhaustive exercise relates to an enhanced cerebrovascular CO(2) reactivity. The CO(2) reactivity was evaluated in six young healthy male...

  1. Flash-Point prediction for binary partially miscible aqueous-organic mixtures

    OpenAIRE

    Liaw, Horng-Jang; Chen, Chien Tsun; Gerbaud, Vincent

    2008-01-01

    Flash point is the most important variable used to characterize fire and explosion hazard of liquids. Herein, partially miscible mixtures are presented within the context of liquid-liquid extraction processes and heterogeneous distillation processes. This paper describes development of a model for predicting the flash point of binary partially miscible mixtures of aqueous-organic system. To confirm the predictive efficiency of the derived flash points, the model was verified by comparing the ...

  2. Flash-point prediction for binary partially miscible mixtures of flammable solvents

    OpenAIRE

    Liaw, Horng-Jang; Lu, Wen-Hung; Gerbaud, Vincent; Chen, Chan-Cheng

    2008-01-01

    Flash point is the most important variable used to characterize fire and explosion hazard of liquids. Herein, partially miscible mixtures are presented within the context of liquid-liquid extraction processes. This paper describes development of a model for predicting the flash point of binary partially miscible mixtures of flammable solvents. To confirm the predictive efficacy of the derived flash points, the model was verified by comparing the predicted values with the experimental data for...

  3. Autotrophic and heterotrophic soil respiration determined with trenching, soil CO2 fluxes and 13CO2/12CO2 concentration gradients in a boreal forest ecosystem

    Science.gov (United States)

    Pumpanen, Jukka; Shurpali, Narasinha; Kulmala, Liisa; Kolari, Pasi; Heinonsalo, Jussi

    2017-04-01

    Soil CO2 efflux forms a substantial part of the ecosystem carbon balance, and it can contribute more than half of the annual ecosystem respiration. Recently assimilated carbon which has been fixed in photosynthesis during the previous days plays an important role in soil CO2 efflux, and its contribution is seasonally variable. Moreover, the recently assimilated C has been shown to stimulate the decomposition of recalcitrant C in soil and increase the mineralization of nitrogen, the most important macronutrient limiting gross primary productivity (GPP) in boreal ecosystems. Podzolic soils, typical in boreal zone, have distinctive layers with different biological and chemical properties. The biological activity in different soil layers has large seasonal variation due to vertical gradient in temperature, soil organic matter and root biomass. Thus, the source of CO2 and its components have a vertical gradient which is seasonally variable. The contribution of recently assimilated C and its seasonal as well as spatial variation in soil are difficult to assess without disturbing the system. The most common method of partitioning soil respiration into its components is trenching which entails the roots being cut or girdling where the flow of carbohydrates from the canopy to roots has been isolated by cutting of the phloem. Other methods for determining the contribution of autotrophic (Ra) and heterotrophic (Rh) respiration components in soil CO2 efflux are pulse labelling with 13CO2 or 14CO2 or the natural abundance of 13C and/or 14C isotopes. Also differences in seasonal and short-term temperature response of soil respiration have been used to separate Ra and Rh. We compared the seasonal variation in Ra and Rh using the trenching method and differences between seasonal and short-term temperature responses of soil respiration. I addition, we estimated the vertical variation in soil biological activity using soil CO2 concentration and the natural abundance of 13C and 12C

  4. Natural CO2 Releases Providing Messages For Stakeholders

    Science.gov (United States)

    Dixon, T.; Romanak, K.; Camps, A. P.

    2011-12-01

    Stakeholder viewpoints and beliefs about geologic carbon storage are not always accurate, yet they may affect the future of carbon capture and storage (CCS). Gaps in stakeholder understanding and perspectives must be addressed, and natural systems that release CO2 can be valuable tools for communicating difficult scientific concepts because they provide tangible examples of geologic principles at work. Stakeholder perceptions commonly involve a misunderstanding of geologic scale and mechanisms, and can be charged with emotions fueled by media coverage of natural disasters. One example of an event widely cited by stakeholders is the CO2 release at Lake Nyos in Cameroon in August 1986 that killed 1700 people. This event is commonly thought by stakeholders to be an analogue for a release from a CO2 storage site; however, this release occurred under a rare combination of circumstances (a 208-m-deep volcanic crater lake) not analogous to an engineered CO2 storage site. Stakeholders therefore gravitate towards natural systems to form concepts and opinions of how CO2 might behave in a geological environment, but they often choose systems that are not true analogues but that gain attention through the media because they are associated with a disaster. When chosen correctly, natural releases of CO2 may create a level of clarity for stakeholders by providing tangible concrete examples that explain difficult scientific principles and provide familiar reference points to adapt different viewpoints. We present suggestions and examples presented by scientists at an IEAGHG Workshop Natural Releases of CO2: Building Knowledge for CO2 Storage Environmental Impact Assessments', held at Maria Laach, Germany, November 2010 which brought together researchers from the EU, North America, Japan, and Australia. It also included field observations of natural CO2 releases around the Laacher See caldera lake, CO2 springs, and the Wallenborn CO2 geyser. New information from international

  5. Achieving Negative CO2 Emissions by Protecting Ocean Chemistry

    Science.gov (United States)

    Cannara, A.

    2016-12-01

    Industrial Age CO2 added 1.8 trillion tons to the atmosphere. About ¼ has dissolved in seas. The rest still dissolves, bolstered by present emissions of >30 gigatons/year. Airborne & oceanic CO2 have induced sea warming & ocean acidification*. This paper suggests a way to induce a negative CO2-emissions environment for climate & oceans - preserve the planet`s dominant CO2-sequestration system ( 1 gigaton/year via calcifying sea life**) by promptly protecting ocean chemistry via expansion of clean power for both lime production & replacement of CO2-emitting sources. Provide natural alkali (CaO, MgO…) to oceans to maintain average pH above 8.0, as indicated by marine biologists. That alkali (lime) is available from past calcifying life's limestone deposits, so can be returned safely to seas once its CO2 is removed & permanently sequestered (Carbfix, BSCP, etc.***). Limestone is a dense source of CO2 - efficient processing per mole sequestered. Distribution of enough lime is possible via cargo-ship transits - 10,000 tons lime/transit, 1 million transits/year. New Panamax ships carry 120,000 tons. Just 10,000/transit allows gradual reduction of present & past CO2 emissions effects, if coupled with combustion-power reductions. CO2 separation from limestone, as in cement plants, consumes 400kWHrs of thermal energy per ton of output lime (or CO2). To combat yearly CO2 dissolution in seas, we must produce & distribute about 10gigatons of lime/year. Only nuclear power produces the clean energy (thousands of terawatt hours) to meet this need - 1000 dedicated 1GWe reactors, processing 12 cubic miles of limestone/year & sequestering CO2 into a similar mass of basalt. Basalt is common in the world. Researchers*** report it provides good, mineralized CO2 sequestration. The numbers above allow gradual CO2 reduction in air and seas, if we return to President Kennedy's energy path: http://tinyurl.com/6xgpkfa We're on an environmental precipice due to failure to eliminate

  6. CO2 emissions from Super-light Structures

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Bagger, Anne

    2011-01-01

    CO2 emission from the construction of buildings is seldom taken into account because focus is primarily on building operation. New technologies have therefore mainly been developed to reduce the energy consumption connected to operation. Super-light technology is a new structural principle giving...... rise to a substantial reduction of the CO2 emission in the construction phase. The present paper describes how the CO2 emission is reduced when using Super-light technology instead of traditional structural components. Estimations of the CO2 emissions from a number of projects using various...... construction methods suggest that building with Super-light structures may cut the CO2 emission in half, compared to traditional concrete structures, and reduce it to 25% compared to traditional steel structures....

  7. Sustainable DME synthesis-design with CO2 utilization

    DEFF Research Database (Denmark)

    Prasertsri, Weeranut; Frauzem, Rebecca; Suriyapraphadilok, Uthaiporn

    Minimizing CO2 emission, while achieving economic feasibility in CO2 utilization for producing valuable chemicals is a challenging problem, as reported in recent studies.Due to its high Cetane number, clean-burning, and non-toxic, DME is a promising fuel alternative, and therefore, potentially...... valuable chemical that can be produced via thermochemical CO2 conversion reactions. The aim of this study is to identify the most promising processing route for sustainable production of DME in terms of CO2 emission, economic indicators and sustainable indicators. The three processing routes are generated......: (A) dry reforming step, methanol synthesis step, and methanoldehydration step; (B) CO2 hydrogenation step followed by methanol dehydration step;and (C) dry reforming step followed by direct DME synthesis step. Starting with a base-case design, the process flow sheets for the three routes are studied...

  8. Modeling of CO2 absorber using an AMP solution

    DEFF Research Database (Denmark)

    Gabrielsen, Jostein; Michelsen, Michael Locht; Stenby, Erling Halfdan

    2006-01-01

    Abstract: An explicit model for carbon dioxide (CO2) solubility in an aqueous solution of 2-amino-2-methyl-1-propanol (AMP) has been proposed and an expression for the heat of absorption of CO2 has been developed as a function of loading and temperature. A rate-based steady-state model for CO2...... absorption into an AMP solution has been proposed, using both the proposed expression for the CO2 solubility and the expression for the heat of absorption along with an expression for the enhancement factor and physicochemical data from the literature. The proposed model has successfully been applied...... to absorption of CO2 into an AMP solution in a packed tower and validated against pilot-plant data from the literature. (c) 2006 American Institute of Chemical Engineers....

  9. Effects of explicit atmospheric convection at high CO2.

    Science.gov (United States)

    Arnold, Nathan P; Branson, Mark; Burt, Melissa A; Abbot, Dorian S; Kuang, Zhiming; Randall, David A; Tziperman, Eli

    2014-07-29

    The effect of clouds on climate remains the largest uncertainty in climate change predictions, due to the inability of global climate models (GCMs) to resolve essential small-scale cloud and convection processes. We compare preindustrial and quadrupled CO2 simulations between a conventional GCM in which convection is parameterized and a "superparameterized" model in which convection is explicitly simulated with a cloud-permitting model in each grid cell. We find that the global responses of the two models to increased CO2 are broadly similar: both simulate ice-free Arctic summers, wintertime Arctic convection, and enhanced Madden-Julian oscillation (MJO) activity. Superparameterization produces significant differences at both CO2 levels, including greater Arctic cloud cover, further reduced sea ice area at high CO2, and a stronger increase with CO2 of the MJO.

  10. Interfacial phenomena at the compressed co2-water interface

    Directory of Open Access Journals (Sweden)

    B. Bharatwaj

    2006-06-01

    Full Text Available Compressed CO2 is considered to be a viable alternative to toxic volatile organic solvents with potential applications in areas including separation reactions, and materials formation processes. Thus an interest in CO2 stems from the fact that it is very inexpensive, has low toxicity, and is not a regulated. However, compressed CO2 has a zero dipole moment and weak van der Waals forces and thus is a poor solvent for both polar and most high molecular weight solutes, characteristics that severely restrict its applicability. In order to overcome this inherent inability, surfactant-stabilized organic and aqueous dispersions in CO2 have been proposed. This work will discuss fundamentals and recent advances in the design of amphiphiles for the novel CO2-water interface.

  11. Feedbacks and the coevolution of plants and atmospheric CO2.

    Science.gov (United States)

    Beerling, David J; Berner, Robert A

    2005-02-01

    The coupled evolution of land plants, CO2, and climate over the last half billion years has maintained atmospheric CO2 concentrations within finite limits, indicating the involvement of a complex network of geophysiological feedbacks. But insight into this important regulatory network is extremely limited. Here we present a systems analysis of the physiological and geochemical processes involved, identifying new positive and negative feedbacks between plants and CO2 on geological time scales. Positive feedbacks accelerated falling CO2 concentrations during the evolution and diversification of terrestrial ecosystems in the Paleozoic and enhanced rising CO2 concentrations across the Triassic-Jurassic boundary during flood basalt eruptions. The existence of positive feedbacks reveals the unexpected destabilizing influence of the biota in climate regulation that led to environmental modifications accelerating rates of terrestrial plant and animal evolution in the Paleozoic.

  12. Compensation of CO2 emissions by air travels: an example

    Directory of Open Access Journals (Sweden)

    Lombardi F

    2011-05-01

    Full Text Available In recent years, several aircraft companies launched awareness campaigns, offering to their passenger the opportunity to known and also calculate their own per-capita CO2 emissions related to the flight they are going to make. Such campaigns permits to the passenger to pay a volunteer contribution in order to compensate their CO2 emissions. In this short communication, some programs undertaken by airline companies are showed. These initiatives are all characterized by a common denominator: the achievement of concrete, proved and verifiable results to compensate the aircraft CO2 emissions. Moreover, also a concrete case is reported as example: it is useful to show which is the per capita CO2 emission for a sample flight in Europe and, quantitatively, the amount of compensation measurements. Finally, this communication highlights on how the estimates of such measurements are usually miscalculated, considering that the capability of forest ecosystems to store CO2 are often underestimated.

  13. PSO 7171 - Oxyfuel Combustion for below zero CO2 emissions

    DEFF Research Database (Denmark)

    Toftegaard, Maja Bøg; Brix, Jacob; Hansen, Brian Brun

    are sought which will enable a significant reduction of the anthropogenic CO2 emissions during the transformation period from the use of fossil fuels to renewable sources of energy. Carbon capture and storage (CCS) has the potential to significantly reduce CO2 emissions from power stations while allowing...... conventional combustion in air by using a mixture of pure oxygen and recirculated flue gas as the combustion medium thereby creating a flue gas highly concentrated in CO2 making the capture process economically more feasible compared to technologies with capture from more dilute CO2 streams. This project has......, and the perspectives for the implementation of oxyfuel combustion s a CO2 sequestration solution in the Danish power production system. Regarding the fundamental combustion characteristics (combustion, emissions, and ash), the project has not identified any disqualifying characteristics. On the contrary, oxyfuel has...

  14. Synthesis and Design of a Sustainable CO2 Utilization Network

    DEFF Research Database (Denmark)

    Frauzem, Rebecca; Gani, Rafiqul

    In response to increasing regulations and concern about the impact of greenhouse gases on the environment, carbon dioxide (CO2) emissions are targeted for reduction. One method is the conversion of CO2 to useful compounds via chemical reactions. However, conversion is still in its infancy...... processing block. CO2 conversion processes show promise as an additional method for the sustainable reduction of CO2 emissions....... a superstructure-based approach a network of utilization alternatives is created linking CO2 and other raw materials with various products using processing blocks. This will then be optimized and verified for sustainability. Detailed design has also been performed for a case study on the methanol synthesis...

  15. [Model study on CO2 removal by photobioreactor].

    Science.gov (United States)

    Cheng, Gui-Lin; Cheng, Li-Hua; Zhou, Cheng-Xu; Zhang, Lin; Chen, Huan-Lin

    2006-09-01

    The key point of study on CO2 removal by microalgae cultured in a photobioreactor is to improve CO2 removal capability. In this paper, a model of air-lift photobioreactor was developed by combination of conditions including the velocity of flow, the degree of mixing, the gas-liquid mass transfer and the rate of photosynthesis, and two corresponding simplified methods, such as time discretization and lumped parameters were put forward. Using a method of lumped parameters, the model for simulation of time course of DO, pH in the column air-lift photobioreactor and prediction of CO2, O2 concentrations in the outlet gas under different CO2 concentration in the aeration gas was thoroughly discussed. Experimental data were also used to verify the model which could potentially be applied to rational design of the photobioreactor, high-density culture of microalgae and efficient removal of CO2.

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

    Science.gov (United States)

    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. Mineral CO2 Sequestration into Basalt: The Carbfix Project

    Science.gov (United States)

    Gislason, S. R.; Broecker, W. S.; Oelkers, E. H.; Gunnlaugsson, E.; Stefansson, A.; Wolff-Boenisch, D.; Matter, J.; Björnsson, G.

    2008-12-01

    The reduction of industrial CO2 emissions is considered one of the main challenges of this century. Among commonly proposed CO2 storage techniques, the injection of anthropogenic CO2 into deep geological formations is quite promising due their large potential storage capacity and geographic ubiquity. Finding a storage solution that is long lasting, thermodynamically stable and environmentally benign would be ideal. Storage of CO2, as solid calcium magnesium iron carbonate, in basaltic rocks may provide such a long lasting, thermodynamically stable and environmentally benign solution. In nature, the carbonization of basaltic rocks occurs in a variety of well-documented settings, such as the hydrothermal alteration in geothermal systems and in deep ocean vent systems. The goal of this research project is to optimize industrial methods for storing CO2 in basaltic rocks through a combined program consisting of, field scale injection of CO2 charged waters into basaltic rocks, laboratory based experiments, study of natural CO2 waters as natural analogue and state of the art geochemical modelling. A second and equally important goal of this research project is to generate the human capital and expertise to apply the advances made in this project in the future. Towards this goal the bulk of the research is to be performed by graduate student and post-doctoral trainees. At the Hellisheidi Iceland site, the hot gases released from geothermal energy production will be processed to separate the CO2. It will then be dissolved in water at about 25 bar pressure and pumped into the porous basalt at 400 to 700 m depth, at the rate of 30 000 tonnes per year. Model simulations, natural analogues and experimental work suggest that the CO2 charged waters will reacts with the basalt and form carbonate minerals such as FeCO3 - MgCO3 solid solutions and CaCO3. By this method the fixed CO2 will remain trapped as mineral for millions of years.

  18. Increasing stomatal conductance in response to rising atmospheric CO2.

    Science.gov (United States)

    Purcell, C; Batke, S P; Yiotis, C; Caballero, R; Soh, W K; Murray, M; McElwain, J C

    2018-01-31

    Studies have indicated that plant stomatal conductance (gs) decreases in response to elevated atmospheric CO2, a phenomenon of significance for the global hydrological cycle. However, gs increases across certain CO2 ranges have been predicted by optimization models. The aim of this work was to demonstrate that under certain environmental conditions, gs can increase in response to elevated CO2. Using (1) an extensive, up-to-date synthesis of gs responses in free air CO2 enrichment (FACE)experiments, (2) in situ measurements across four biomes showing dynamic gs responses to a CO2 rise of ~50 ppm (characterizing the change in this greenhouse gas over the past three decades) and (3) a photosynthesis-stomatal conductance model, it is demonstrated that gs can in some cases increase in response to increasing atmospheric CO2. Field observations are corroborated by an extensive synthesis of gs responses in FACE experiments showing that 11.8 % of gs responses under experimentally elevated CO2 are positive. They are further supported by a strong data-model fit (r2 = 0.607) using a stomatal optimization model applied to the field gs dataset. A parameter space identified in the Farquhar-Ball-Berry photosynthesis-stomatal conductance model confirms field observations of increasing gs under elevated CO2 in hot dry conditions. Contrary to the general assumption, positive gs responses to elevated CO2, although relatively rare, are a feature of woody taxa adapted to warm, low-humidity conditions, and this response is also demonstrated in global simulations using the Community Land Model (CLM4). The results contradict the over-simplistic notion that global vegetation always responds with decreasing gs to elevated CO2, a finding that has important implications for predicting future vegetation feedbacks on the hydrological cycle at the regional level.

  19. CO2 on the International Space Station: An Operations Update

    Science.gov (United States)

    Law, Jennifer; Alexander, David

    2016-01-01

    PROBLEM STATEMENT: We describe CO2 symptoms that have been reported recently by crewmembers on the International Space Station and our continuing efforts to control CO2 to lower levels than historically accepted. BACKGROUND: Throughout the International Space Station (ISS) program, anecdotal reports have suggested that crewmembers develop CO2-related symptoms at lower CO2 levels than would be expected terrestrially. Since 2010, operational limits have controlled the 24-hour average CO2 to 4.0 mm Hg, or below as driven by crew symptomatology. In recent years, largely due to increasing awareness by crew and ground team, there have been increased reports of crew symptoms. The aim of this presentation is to discuss recent observations and operational impacts to lower CO2 levels on the ISS. CASE PRESENTATION: Crewmembers are routinely asked about CO2 symptoms in their weekly private medical conferences with their crew surgeons. In recent ISS expeditions, crewmembers have noted symptoms attributable to CO2 starting at 2.3 mmHg. Between 2.3 - 2.7 mm Hg, fatigue and full-headedness have been reported. Between 2.7 - 3.0 mm Hg, there have been self-reports of procedure missed steps or procedures going long. Above 3.0 - 3.4 mm Hg, headaches have been reported. A wide range of inter- and intra-individual variability in sensitivity to CO2 have been noted. OPERATIONAL / CLINICAL RELEVANCE: These preliminary data provide semi-quantitative ranges that have been used to inform a new operational limit of 3.0 mmHg as a compromise between systems capabilities and the recognition that there are human health and performance impacts at recent ISS CO2 levels. Current evidence would suggest that an operational limit between 0.5 and 2.0 mm Hg may maintain health and performance. Future work is needed to establish long-term ISS and future vehicle operational limits.

  20. Transient nature of CO2 fertilization in Arctic tundra

    Science.gov (United States)

    Oechel, Walter C.; Cowles, Sid; Grulke, Nancy; Hastings, Steven J.; Lawrence, Bill; Prudhomme, Tom; Riechers, George; Strain, Boyd; Tissue, David; Vourlitis, George

    1994-10-01

    THERE has been much debate about the effect of increased atmospheric CO2 concentrations on plant net primary production1,3 and on net ecosystem CO2 flux3-10. Apparently conflicting experimental findings could be the result of differences in genetic potential11-15 and resource availability16-20, different experimental conditions21-24 and the fact that many studies have focused on individual components of the system2,21,25-27 rather than the whole ecosystem. Here we present results of an in situ experiment on the response of an intact native ecosystem to elevated CO2. An undisturbed patch of tussock tundra at Toolik Lake, Alaska, was enclosed in greenhouses in which the CO2 level, moisture and temperature could be controlled28, and was subjected to ambient (340 p.p.m.) and elevated (680 p.p.m.) levels of CO2 and temperature (+4 °C). Air humidity, precipitation and soil water table were maintained at ambient control levels. For a doubled CO2 level alone, complete homeostasis of the CO2 flux was re-established within three years, whereas the regions exposed to a combination of higher temperatures and doubled CO2 showed persistent fertilization effect on net ecosystem carbon sequestration over this time. This difference may be due to enhanced sink activity from the direct effects of higher temperatures on growth16,29-33 and to indirect effects from enhanced nutrient supply caused by increased mineralization10,11,19,27,34. These results indicate that the responses of native ecosystems to elevated CO2 may not always be positive, and are unlikely to be straightforward. Clearly, CO2 fertilization effects must always be considered in the context of genetic limitation, resource availability and other such factors.

  1. CuZn Alloy- Based Electrocatalyst for CO2 Reduction

    KAUST Repository

    Alazmi, Amira

    2014-06-01

    ABSTRACT CuZn Alloy- Based Electrocatalyst for CO2 Reduction Amira Alazmi Carbon dioxide (CO2) is one of the major greenhouse gases and its emission is a significant threat to global economy and sustainability. Efficient CO2 conversion leads to utilization of CO2 as a carbon feedstock, but activating the most stable carbon-based molecule, CO2, is a challenging task. Electrochemical conversion of CO2 is considered to be the beneficial approach to generate carbon-containing fuels directly from CO2, especially when the electronic energy is derived from renewable energies, such as solar, wind, geo-thermal and tidal. To achieve this goal, the development of an efficient electrocatalyst for CO2 reduction is essential. In this thesis, studies on CuZn alloys with heat treatments at different temperatures have been evaluated as electrocatalysts for CO2 reduction. It was found that the catalytic activity of these electrodes was strongly dependent on the thermal oxidation temperature before their use for electrochemical measurements. The polycrystalline CuZn electrode without thermal treatment shows the Faradaic efficiency for CO formation of only 30% at applied potential ~−1.0 V vs. RHE with current density of ~−2.55 mA cm−2. In contrast, the reduction of oxide-based CuZn alloy electrode exhibits 65% Faradaic efficiency for CO at lower applied potential about −1.0 V vs. RHE with current density of −2.55 mA cm−2. Furthermore, stable activity was achieved over several hours of the reduction reaction at the modified electrodes. Based on electrokinetic studies, this improvement could be attributed to further stabilization of the CO2•− on the oxide-based Cu-Zn alloy surface.

  2. Phase-field modelling of a miscible system in spinning droplet tensiometer.

    Science.gov (United States)

    Vorobev, Anatoliy; Boghi, Andrea

    2016-11-15

    The spinning drop tensiometry is used for measurements of surface tension coefficients, especially, when interfaces are characterised by low and ultra-low interfacial stresses. A droplet of lighter liquid is introduced into a rotating capillary that was initially saturated with another heavier liquid. The tube is subject to axial rotation that results in droplet's elongation along the tube's axis. The equilibrium shape of the droplet is used to determine the surface tension coefficient. In this work, the evolution of a slowly miscible droplet introduced into a spinning capillary is investigated. This technique is frequently employed for studies of the dynamics of miscible systems, even despite the fact that a strict equilibrium is never achieved in a mixture of fully miscible liquids. The numerical modelling of a miscible droplet is fulfilled on the basis of the phase-field (Cahn-Hilliard) approach. The numerical results are compared against the experimental data pursuing two objectives: (i) to verify the use of the phase-field approach as a consistent physics-based approach capable of accurate tracking of the short- and long-term evolution of miscible systems, and (ii) to estimate the values of the phenomenological parameters introduced within the phase-field approach, so making this approach a practical tool for modelling of thermohydrodynamic changes in miscible systems within various configurations. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Numerical modeling of CO2 sequestration inside a fracture in porous media based on space discretization by means of integral finite difference method

    Science.gov (United States)

    Alizadeh Nomeli, M.; Riaz, A.

    2012-12-01

    Increasing concentration of CO2 as a greenhouse gas in the atmosphere causes global warming and it subsequently perturbs the balance of the life cycle. In order to mitigate the concentration of CO2 in the atmosphere, the sequestration of CO2 into deep geological formations has been investigated theoretically and experimentally in recent decades. Solubility and mineral trapping are the most promising long term solutions to geologic CO2 sequestration, because they prevent its return to the atmosphere. In this study, the CO2 sequestration capacity of both aqueous and mineral phases is evaluated. Mineral alterations, however, are too slow to be modeled experimentally; therefore a numerical model is required. This study presents a model to simulate a reactive fluid within permeable porous media. The problem contains reactive transport modeling between a miscible flow and minerals in post-injection regime. Rates of dissolution and precipitation (PD) of minerals are determined by taking into account the pH of the system, in addition to the consideration of the influence of temperature. We solve fluid convection, diffusion and PD reactions inside a fracture in order to predict the amount of CO2 that can be stored as precipitation of secondary carbonates after specific period of time. The modeling of flow and transport inside the fracture for the mineral trapping purpose is based on space discretization by means of integral finite differences. Dissolution and precipitation of all minerals in simulations presented in the current study are assumed to be kinetically controlled. Therefore the model can monitor changes in porosity and permeability during the simulation from changes in the volume of the fracture.

  4. Photosynthetic responses to elevated CO(2) and O(3) in Quercus ilex leaves at a natural CO(2) spring.

    Science.gov (United States)

    Paoletti, E; Seufert, G; Della Rocca, G; Thomsen, H

    2007-06-01

    Photosynthetic stimulation and stomatal conductance (Gs) depression in Quercus ilex leaves at a CO(2) spring suggested no down-regulation. The insensitivity of Gs to a CO(2) increase (from ambient 1500 to 2000 micromol mol(-1)) suggested stomatal acclimation. Both responses are likely adaptations to the special environment of CO(2) springs. At the CO(2)-enriched site, not at the control site, photosynthesis decreased 9% in leaves exposed to 2x ambient O(3) concentrations in branch enclosures, compared to controls in charcoal-filtered air. The stomatal density reduction at high CO(2) was one-third lower than the concomitant Gs reduction, so that the O(3) uptake per single stoma was lower than at ambient CO(2). No significant variation in monoterpene emission was measured. Higher trichome and mesophyll density were recorded at the CO(2)-enriched site, accounting for lower O(3) sensitivity. A long-term exposure to H(2)S, reflected by higher foliar S-content, and CO(2) might depress the antioxidant capacity of leaves close to the vent and increase their O(3) sensitivity.

  5. Elevated CO2 and nitrogen effects on soil CO2 flux from a pasture upon return to cultivation

    Science.gov (United States)

    Soil CO2 efflux patterns associated with converting pastures back to row crop production remain understudied in the Southeastern U.S. A 10-year study of bahiagrass (Paspalum notatum Flüggé) response to elevated CO2 was conducted using open top field chambers on a Blanton loamy sand (loamy siliceous,...

  6. Effects of atmospheric CO2 enrichment on soil CO2 efflux in a young longleaf pine system

    Science.gov (United States)

    G. Brett Runion; John R. Butnor; S. A. Prior; R. J. Mitchell; H. H. Rogers

    2012-01-01

    The southeastern landscape is composed of agricultural and forest systems that can store carbon (C) in standing biomass and soil. Research is needed to quantify the effects of elevated atmospheric carbon dioxide (CO2) on terrestrial C dynamics including CO2 release back to the atmosphere and soil sequestration. Longleaf...

  7. Membrane-assisted CO2 liquefaction: performance modelling of CO2 capture from flue gas in cement production

    NARCIS (Netherlands)

    Bouma, R.H.B.; Vercauteren, F.F.; Os, P.J. van; Goetheer, E.L.V.; Berstad, D.; Anantharaman, R.

    2017-01-01

    CEMCAP is an international R&D project under the Horizon 2020 Programme preparing the ground for the large-scale implementation of CO2 capture in the European cement industry. This paper concerns the performance modeling of membraneassisted CO2 liquefaction as a possible retrofit application for

  8. CO2 Fixation into Novel CO2 Storage Materials Composed of 1,2-Ethanediamine and Ethylene Glycol Derivatives.

    Science.gov (United States)

    Zhao, Tianxiang; Guo, Bo; Han, Limin; Zhu, Ning; Gao, Fei; Li, Qiang; Li, Lihua; Zhang, Jianbin

    2015-07-20

    A new CO2 fixation process into solid CO2 -storage materials (CO2 SMs) under mild conditions has been developed. The novel application of amine-glycol systems to the capture, storage, and utilization of CO2 with readily available 1,2-ethanediamine (EDA) and ethylene glycol derivatives (EGs) was demonstrated. Typically, the CO2 SMs were isolated in 28.9-47.5 % yields, followed by extensive characterization using (13) C NMR, XRD, and FTIR. We found that especially the resulting poly-ethylene-glycol-300-based CO2 SM (PCO2 SM) product could be processed into stable tablets for CO2 storage; the aqueous PCO2 SM solution exhibited remarkable CO2 capturing and releasing capabilities after multiple cycles. Most importantly, the EDA and PEG 300 released from PCO2 SM were found to act as facilitative surfactants for the multiple preparation of CaCO3 microparticles with nano-layer structure. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Characterization of CO2 and mixed methane/CO2 hydrates intercalated in smectites by means of atomistic calculations.

    Science.gov (United States)

    Martos-Villa, Rubén; Mata, M Pilar; Sainz-Díaz, C Ignacio

    2014-04-01

    The recent increase in anthropogenic CO2 gas released to the atmosphere and its contribution to global warming make necessary to investigate new ways of CO2 storage. Injecting CO2 into subsurface CH4 hydrate reservoirs would displace some of the CH4 in the hydrate crystal lattice, converting simple CH4 hydrates into either simple CO2 hydrates or mixed CH4CO2 hydrates. Molecular simulations were performed to determine the structure and behavior of CO2 and mixed hydrate complexes in the interlayer of Na-rich montmorillonite and beidellite smectite. Molecular Dynamics (MD) simulations used NPT ensembles in a 4×4×1 supercell comprised of montmorillonite or beidellite with CO2 or mixed CH4/CO2 hydrate complexes in the interlayer. The smectite 2:1 layer surface helps provide a stabilizing influence on the formation of gas hydrate complexes. The type of smectite affects the stability of the smectite-hydrate complexes, where high charge located on the tetrahedral layer of the smectites disfavor the formation of hydrate complexes. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Ab initio studies on [bmim][PF6]–CO2 mixture and CO2 clusters

    Indian Academy of Sciences (India)

    Wintec

    on CO2 clusters reveals the greater tendency of the clusters with more CO2 units, to deviate from the linear geometry. Keywords. Ionic liquids; supercritical carbon dioxide; ab initio; molecular dynamics. 1. Introduction. The increase in the pollution level due to the solvents used currently in industries demands alternative ...

  11. An estimate of monthly global emissions of anthropogenic CO2: Impact on the seasonal cycle of atmospheric CO2

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, D [Oak Ridge National Laboratory (ORNL); Mills, R [Oak Ridge National Laboratory (ORNL); Gregg, J [University of Maryland; Blasing, T J [ORNL; Hoffman, F [Oak Ridge National Laboratory (ORNL); Andres, Robert Joseph [ORNL; Devries, M [Oak Ridge National Laboratory (ORNL); Zhu, Z [NASA Goddard Space Flight Center; Kawa, S [NASA Goddard Space Flight Center

    2008-01-01

    Monthly estimates of the global emissions of anthropogenic CO2 are presented. Approximating the seasonal CO2 emission cycle using a 2-harmonic Fourier series with coefficients as a function of latitude, the annual fluxes are decomposed into monthly flux estimates based on data for the United States and applied globally. These monthly anthropogenic CO2 flux estimates are then used to model atmospheric CO2 concentrations using meteorological fields from the NASA GEOS-4 data assimilation system. We find that the use of monthly resolved fluxes makes a significant difference in the seasonal cycle of atmospheric CO2 in and near those regions where anthropogenic CO2 is released to the atmosphere. Local variations of 2-6 ppmv CO2 in the seasonal cycle amplitude are simulated; larger variations would be expected if smaller source-receptor distances could be more precisely specified using a more refined spatial resolution. We also find that in the midlatitudes near the sources, synoptic scale atmospheric circulations are important in the winter and that boundary layer venting and diurnal rectifier effects are more important in the summer. These findings have implications for inverse-modeling efforts that attempt to estimate surface source/sink regions especially when the surface sinks are colocated with regions of strong anthropogenic CO2 emissions.

  12. Lessons Learned From Recent Research on Internal CO2 Transport in Trees. Part I, CO2 Efflux and Respiration

    Science.gov (United States)

    McGuire, M. A.; Bloemen, J.; Aubrey, D. P.; Steppe, K.; Teskey, R. O.

    2016-12-01

    Currently, the most pressing problem regarding respiration in trees is determining the rate of respiration in woody tissues. In stems and roots, barriers to diffusion promote the buildup of CO2 from respiration to high concentrations, often in the range of 3 to 10% and sometimes exceeding 20%, substantially higher than that of the atmosphere ( 0.04%). A substantial portion of this internal CO2 released from respiring cells in roots and stems can dissolve in xylem sap and move upward in the xylem stream, resulting in internal transport of respired CO2 that rivals the efflux of respired CO2from woody tissues. The importance of such internal CO2 transport for the assessment of above- and below-ground respiration has gained increasing interest and here we will synthesize the latest research. The most important recent finding has been that in tree roots, a large fraction of respired CO2 remains within the root system rather than diffusing into the soil. This CO2 is transported in xylem sap into the shoot, and because respiration is almost always measured as the flux of CO2 into the atmosphere from plant tissues, it represents an unaccounted- for component of tree root metabolism. In Populus deltoides trees, for which xylem CO2 transport and soil CO2 efflux near the tree was measured, twice the amount of CO2 derived from below-ground autotrophic respiration entered the xylem stream as diffused into the soil environment. For both Eucalyptus and Quercus, up to 24 and 19% of root-respired CO2 was transported via the transpiration stream, respectively, illustrating that a significant internal transport of root-respired CO2 is present across a wide range of plant families. These findings suggest that root and soil respiration can be substantially underestimated by "soil-centric" measurements. Moreover, internal transport of respired CO2, which has only recently been recognized and measured, has important implications for our understanding of carbon dynamics at both plant and

  13. CO2 with Mechanical Subcooling vs. CO2 Cascade Cycles for Medium Temperature Commercial Refrigeration Applications Thermodynamic Analysis

    Directory of Open Access Journals (Sweden)

    Laura Nebot-Andrés

    2017-09-01

    Full Text Available A recent trend to spread the use of CO2 refrigeration cycles in warm regions of the world is to combine a CO2 cycle with another one using a high performance refrigerant. Two alternatives are being considered: cascade and mechanical subcooling systems. Both respond to a similar configuration of the refrigeration cycle, they being based on the use of two compressors and same number of heat exchangers. However, the compressor, heat exchanger sizes and energy performance differ a lot between them. This work, using experimental relations for CO2 and R1234yf semi-hermetic compressors analyzes in depth both alternatives under the warm climate of Spain. In general, it was concluded that the CO2 refrigeration solution with mechanical subcooling would cover all the conditions with high overall energy efficiency, thus it being recommended for further extension of the CO2 refrigeration applications.

  14. Measurement of total CO2 in microliter samples of urine and other biological fluids using infrared detection of CO2.

    Science.gov (United States)

    Trepiccione, Francesco; Iena, Francesco Maria; Catalini, Laura; Carpi, Francesco Martino; Koed, Mogens; Frische, Sebastian

    2017-06-05

    The purpose of this study is to describe a low-cost and simply made instrument capable of measuring the total CO2 content of microliter volumes of biological fluids utilizing a commercially available CO2 sensor based on a NDIR detector. The described instrument is based on transformation of dissolved HCO3- to CO2 by acidification and subsequent measurement of the produced CO2. The instrument has a linear response in the range 0.025-10 μmol HCO3-, which enables measurements in fresh urine and plasma samples down to 5 μl. The values from plasma were compared to measurements made on 65 μl whole blood in an automatic blood gas analyzer and found not to differ significantly. Compared to currently commercially available instruments applying the same principles to measure total CO2, this study provides a simple and robust alternative which even can be used on smaller sample volumes.

  15. Zeta potential in oil-water-carbonate systems and its impact on oil recovery during controlled salinity water-flooding.

    Science.gov (United States)

    Jackson, Matthew D; Al-Mahrouqi, Dawoud; Vinogradov, Jan

    2016-11-23

    Laboratory experiments and field trials have shown that oil recovery from carbonate reservoirs can be increased by modifying the brine composition injected during recovery in a process termed controlled salinity water-flooding (CSW). However, CSW remains poorly understood and there is no method to predict the optimum CSW composition. This work demonstrates for the first time that improved oil recovery (IOR) during CSW is strongly correlated to changes in zeta potential at both the mineral-water and oil-water interfaces. We report experiments in which IOR during CSW occurs only when the change in brine composition induces a repulsive electrostatic force between the oil-brine and mineral-brine interfaces. The polarity of the zeta potential at both interfaces must be determined when designing the optimum CSW composition. A new experimental method is presented that allows this. Results also show for the first time that the zeta potential at the oil-water interface may be positive at conditions relevant to carbonate reservoirs. A key challenge for any model of CSW is to explain why IOR is not always observed. Here we suggest that failures using the conventional (dilution) approach to CSW may have been caused by a positively charged oil-water interface that had not been identified.

  16. Improving soil CO2 efflux estimates from in-situ soil CO2 sensors with gas transport measurements

    Science.gov (United States)

    Sanchez-Canete, E. P.; Barron-Gafford, G.; Van Haren, J. L. M.; Scott, R. L.

    2015-12-01

    Correctly estimating soil carbon dioxide (CO2) fluxes emitted to the atmosphere is essential because they are a large component of the ecosystem carbon balance. Continuous estimates of soil CO2 flux, especially when paired with eddy covariance measurements of whole-ecosystem CO­2 exchange, help to disaggregate net ecosystem CO2 exchange. Most researchers estimate soil CO2 fluxes by applying the gradient method; however, this is only appropriate in the absence of advective or convective processes. Given the rarity of such static states, we must move toward measurement techniques that will allow us to quantify the dynamic soil efflux system with gas transport by convective, advective and molecular diffusion processes. Convective processes are mainly relevant in caves, where values of relative humidity, temperature and CO2 molar fraction determine the buoyancy of the external-internal air masses. These convective processes also are important in large fractures when temperature differences between surface and depth can generate convection, transporting CO2 from deep layers to the atmosphere. Advective processes occur both in caves and in soils, and the CO2 exchanges are mainly due to three factors: wind, changes in atmospheric pressure, and changes in the water table. Molecular diffusion processes are being widely applied in the determination of soil-atmosphere gas exchanges by applying the gradient method. However, the use of the gradient method can yield inappropriate flux estimates due to the uncertainties mainly associated with the inappropriate determination of the soil diffusion coefficient. Therefore, in-situ methods to determine diffusion coefficient are necessary to obtain accurate CO2 fluxes. If this is resolved, the gradient method has great potential to become the most used technique to monitor atmosphere-soil CO2 exchanges within the next few years. Here we review the state of the science and describe a series of field measurements for significantly

  17. Environmental potential of the use of CO2 from alcoholic fermentation processes. The CO2-AFP strategy.

    Science.gov (United States)

    Alonso-Moreno, Carlos; García-Yuste, Santiago

    2016-10-15

    A novel Carbon Dioxide Utilization (CDU) approach from a relatively minor CO2 emission source, i.e., alcoholic fermentation processes (AFP), is presented. The CO2 produced as a by-product from the AFP is estimated by examining the EtOH consumed per year reported by the World Health Organization in 2014. It is proposed that the extremely pure CO2 from the AFP is captured in NaOH solutions to produce one of the Top 10 commodities in the chemical industry, Na2CO3, as a good example of an atomic economy process. The novel CDU strategy could yield over 30.6Mt of Na2CO3 in oversaturated aqueous solution on using ca. 12.7Mt of captured CO2 and this process would consume less energy than the synthetic methodology (Solvay ammonia soda process) and would not produce low-value by-products. The quantity of Na2CO3 obtained by this strategy could represent ca. 50% of the world Na2CO3 production in one year. In terms of the green economy, the viability of the strategy is discussed according to the recommendations of the CO2Chem network, and an estimation of the CO2negative emission achieved suggests a capture of around 280.0Mt of CO2 from now to 2020 or ca. 1.9Gt from now to 2050. Finally, the results obtained for this new CDU proposal are discussed by considering different scenarios; the CO2 production in a typical winemaking corporation, the CO2 released in the most relevant wine-producing countries, and the use of CO2 from AFP as an alternative for the top Na2CO3-producing countries. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Annual CO2 budget and seasonal CO2 exchange signals at a High Arctic permafrost site on Spitsbergen, Svalbard archipelago

    Science.gov (United States)

    Lüers, J.; Westermann, S.; Piel, K.; Boike, J.

    2014-01-01

    The annual variability of CO2 exchange in most ecosystems is primarily driven by the activities of plants and soil microorganisms. However, little is known about the carbon balance and its controlling factors outside the growing season in arctic regions dominated by soil freeze/thaw-processes, long-lasting snow cover, and several months of darkness. This study presents a complete annual cycle of the CO2 net ecosystem exchange (NEE) dynamics for a High Arctic tundra area on the west coast of Svalbard based on eddy-covariance flux measurements. The annual cumulative CO2 budget is close to zero grams carbon per square meter per year, but shows a very strong seasonal variability. Four major CO2 exchange seasons have been identified. (1) During summer (ground snow-free), the CO2 exchange occurs mainly as a result of biological activity, with a predominance of strong CO2 assimilation by the ecosystem. (2) The autumn (ground snow-free or partly snow-covered) is dominated by CO2 respiration as a result of biological activity. (3) In winter and spring (ground snow-covered), low but persistent CO2 release occur, overlain by considerable CO2 exchange events in both directions associated with changes of air masses and air and atmospheric CO2 pressure. (4) The snow melt season (pattern of snow-free and snow-covered areas), where both, meteorological and biological forcing, resulting in a visible carbon uptake by the high arctic ecosystem. Data related to this article are archived under: http://doi.pangaea.de/10.1594/PANGAEA.809507.

  19. Seasonal and temporal CO2 dynamics in three tropical mangrove creeks - A revision of global mangrove CO2 emissions

    Science.gov (United States)

    Rosentreter, Judith A.; Maher, D. T.; Erler, D. V.; Murray, R.; Eyre, B. D.

    2018-02-01

    Continuous high-resolution surface water pCO2 and δ13C-CO2 and 222Rn (dry season only) were measured over two tidal cycles in the wet and dry season in three tropical tidal mangrove creeks on the north-eastern coast of Queensland, Australia. Mangrove surface water pCO2 followed a clear tidal pattern (ranging from 387 to 13,031 μatm) with higher pCO2-values in the wet season than in the dry season. The δ13C-CO2 in the mangrove waters ranged from -21.7 to -8.8‰ and was rather indicative of a mixed source than a distinct mangrove signature. Surface water CO2 was likely driven by a combination of mangrove and external carbon sources, e.g. exchange with groundwater/pore water enriched in 13C, or terrestrial carbon inputs with a significant contribution of C4-vegetation (sugar cane) source. The kinetic and equilibrium fractionation during the gas exchange at the water-atmosphere interface may have further caused a 13C-enrichment of the CO2 pool in the mangrove surface waters. Average CO2 evasion rates (58.7-277.6 mmol m-2 d-1) were calculated using different empirical gas transfer velocity models. Using our high-resolution time series data and previously published data, the average CO2 flux rate in mangrove ecosystems was estimated to be 56.5 ± 8.9 mmol m-2 d-1, which corresponds to a revised global mangrove CO2 emission of 34.1 ± 5.4 Tg C per year.

  20. Progress Toward Measuring CO2 Isotopologue Fluxes in situ with the LLNL Miniature, Laser-based CO2 Sensor

    Science.gov (United States)

    Osuna, J. L.; Bora, M.; Bond, T.

    2015-12-01

    One method to constrain photosynthesis and respiration independently at the ecosystem scale is to measure the fluxes of CO2­ isotopologues. Instrumentation is currently available to makes these measurements but they are generally costly, large, bench-top instruments. Here, we present progress toward developing a laser-based sensor that can be deployed directly to a canopy to passively measure CO2 isotopologue fluxes. In this study, we perform initial proof-of-concept and sensor characterization tests in the laboratory and in the field to demonstrate performance of the Lawrence Livermore National Laboratory (LLNL) tunable diode laser flux sensor. The results shown herein demonstrate measurement of bulk CO2 as a first step toward achieving flux measurements of CO2 isotopologues. The sensor uses a Vertical Cavity Surface Emitting Laser (VCSEL) in the 2012 nm range. The laser is mounted in a multi-pass White Cell. In order to amplify the absorption signal of CO2 in this range we employ wave modulation spectroscopy, introducing an alternating current (AC) bias component where f is the frequency of modulation on the laser drive current in addition to the direct current (DC) emission scanning component. We observed a strong linear relationship (r2 = 0.998 and r2 = 0.978 at all and low CO2 concentrations, respectively) between the 2f signal and the CO2 concentration in the cell across the range of CO2 concentrations relevant for flux measurements. We use this calibration to interpret CO2 concentration of a gas flowing through the White cell in the laboratory and deployed over a grassy field. We will discuss sensor performance in the lab and in situ as well as address steps toward achieving canopy-deployed, passive measurements of CO2 isotopologue fluxes. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-675788

  1. Adsorption of CO2 by alginate immobilized zeolite beads

    Science.gov (United States)

    Suratman, A.; Kunarti, E. S.; Aprilita, N. H.; Pamurtya, I. C.

    2017-03-01

    Immobilized zeolit in alginate beads for adsorption of CO2 was developed. Alginate immobilized zeolit beads was generated by dropping the mixture of Na-alginate and zeolite solution into Ca2+ solution. The adsorption efficacy such as the influence of contact time, mass of zeolite, flowrate of CO2, and mass of adsorbent was evaluated. The adsorption of CO2 onto alginate immobilized zeolit beads was investigated by performing both equilibrium and kinetic batch test. Bead was characterized by FTIR and SEM. Alginate immobilized zeolit beads demonstrated significantly higher sorption efficacy compared to plain alginate beads and zeolite with 0.25 mmol CO2 adsorbed /g adsorbent. Optimum condition was achieved with mass composition of alginate:zeolite (3:1), flowrate 50 mL/min for 20 minutes. The alginate immobilized zeolit beads showed that adsorption of CO2 followed Freundlich isotherm and pseudo second order kinetic model. Adsorption of CO2 onto alginate immobilized zeolite beads is a physisorption with adsorption energy of 6.37 kJ/mol. This results indicates that the alginate immobilized zeolit beads can be used as promising adsorbents for CO2.

  2. Trends in global CO2 emissions. 2012 Report

    Energy Technology Data Exchange (ETDEWEB)

    Olivier, J.G.J.; Peters, J.A.H.W. [PBL Netherlands Environmental Assessment Agency, Den Haag (Netherlands); Janssens-Maenhout, G. [Institute for Environment and Sustainability IES, European Commission' s Joint Research Centre JRC, Ispra (Italy)

    2012-07-15

    This report discusses the results of a trend assessment of global CO2 emissions up to 2011 and updates last year's assessment. This assessment focusses on the changes in annual CO2 emissions from 2010 to 2011, and includes not only fossil fuel combustion on which the BP reports are based, but also incorporates all other relevant CO2 emissions sources including flaring of waste gas during oil production, cement clinker production and other limestone uses, feedstock and other non-energy uses of fuels, and several other small sources. After a short description of the methods used (Chapter 2), we first present a summary of recent CO2 emission trends, by region and by country, and of the underlying trend of fossil fuel use, non-fossil energy and of other CO2 sources (Chapter 3). To provide a broader context of the global trends we also assess the cumulative global CO2 emissions of the last decade, i.e. since 2000, and compare it with scientific literature that analyse global emissions in relation to the target of 2C maximum global warming in the 21st century, which was adopted in the UN climate negotiations (Chapter 4). Compared to last year's report, Annex 1 includes a more detailed and updated discussion of the uncertainty in national and global CO2 emission estimates.

  3. Mesoscale modelling of atmospheric CO2 across Denmark

    DEFF Research Database (Denmark)

    Lansø, Anne Sofie

    2016-01-01

    It is scientifically well-established that the increase of atmospheric CO2 affects the entire globe and will lead to higher surface temperatures. Although anthropogenic CO2is emitted straight into the atmosphere, it does not all contribute to the existing atmospheric CO2 reservoir. Approximately 29......% is taken up by the global oceans, due to under-saturation of CO2 in the surface waters, while another 33 % is taken up by the terrestrial biosphere, via photosynthesis. In order to estimate the effects of increasing anthropogenic emissions of CO2 more accurately in the future, it is essential to understand...... the processes controlling the sources and sinks of atmospheric CO2. This PhD dissertation attempts to increase our understanding of the importance of accounting for high spatiotemporal variability in estimates of CO2 exchanges between the atmosphere and the surface. For this purpose, a mesoscale...

  4. The possible evolution and future of CO2-concentrating mechanisms.

    Science.gov (United States)

    Raven, John A; Beardall, John; Sánchez-Baracaldo, Patricia

    2017-06-01

    CO2-concentrating mechanisms (CCMs), based either on active transport of inorganic carbon (biophysical CCMs) or on biochemistry involving supplementary carbon fixation into C4 acids (C4 and CAM), play a major role in global primary productivity. However, the ubiquitous CO2-fixing enzyme in autotrophs, Rubisco, evolved at a time when atmospheric CO2 levels were very much higher than today and O2 was very low and, as CO2 and O2 approached (by no means monotonically), today's levels, at some time subsequently many organisms evolved a CCM that increased the supply of CO2 and decreased Rubisco oxygenase activity. Given that CO2 levels and other environmental factors have altered considerably between when autotrophs evolved and the present day, and are predicted to continue to change into the future, we here examine the drivers for, and possible timing of, evolution of CCMs. CCMs probably evolved when CO2 fell to 2-16 times the present atmospheric level, depending on Rubisco kinetics. We also assess the effects of other key environmental factors such as temperature and nutrient levels on CCM activity and examine the evidence for evolutionary changes in CCM activity and related cellular processes as well as limitations on continuity of CCMs through environmental variations. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. Varied growth response of cogongrass ecotypes to elevated CO2

    Directory of Open Access Journals (Sweden)

    G. Brett Runion

    2016-01-01

    Full Text Available Cogongrass [Imperata cylindrica (L. P. Beauv] is an invasive C4 perennial grass which is listed as one of the top ten worst weeds in the world and is a major problem in the Southeast US. Five cogongrass ecotypes (Florida, Hybrid, Louisiana, Mobile, and North Alabama collected across the Southeast and a red-tip ornamental variety were container grown for six months in open top chambers under ambient and elevated (ambient plus 200 ppm atmospheric CO2. Elevated CO2 increased average dry weight (13% which is typical for grasses. Elevated CO2 increased height growth and both nitrogen and water use efficiencies, but lowered tissue nitrogen concentration; again, these are typical plant responses to elevated CO2. The hybrid ecotype tended to exhibit the greatest growth (followed by Louisiana, North Alabama, and Florida ecotypes while the red-tip and Mobile ecotypes were smallest. Interactions of CO2 with ecotype generally showed that the hybrid, Louisiana, Florida, and/or North Alabama ecotypes showed a positive response to CO2 while the Mobile and red-tip ecotypes did not. Cogongrass is a problematic invasive weed in the southeastern U.S. and some ecotypes may become more so as atmospheric CO2 continues to rise.

  6. Clinical effects of CO2 laser on equine diseases

    Science.gov (United States)

    Lindholm, Arne; Svensson, Ulf; Collinder, Eje

    2002-10-01

    CO2 lasers has been used for five years at Malaren Equine Hospital, as an alternative treatment of some equine diseases. The application of CO2 laser has been studied for evaluation of its appropriateness for treatment of the equine diseases sarcoids, lameness in fetlock joints or pulmonary haemorrhage. During the last five years, above 100 equine sarcoids have been removed by laser surgery (CO2 laser) and so far resulting in significantly few recurrences compared with results from usual excision surgery. In one study, acute traumatic arthritis in fetlock joints was treated three times every second day with defocalised CO2 laser. The therapeutic effectiveness of CO2 laser in this study was better than that of the customary therapy with betamethasone plus hyaluronan. During one year, chronic pulmonary bleeders, namely exercise induced pulmonary haemorrhage, has been treated with defocalised CO2 laser. Six race horses have been treated once daily during five days. Until now, three of these horses have subsequently been successfully racing and no symptoms of pulmonary haemorrhage have been observed. These studies indicate that CO2 laser might be an appropriate therapy on sarcoids and traumatic arthritis, and probably also on exercise induced pulmonary haemorrhage. Other treatments for this pulmonary disease are few.

  7. A uniform, quality controlled Surface Ocean CO2 Atlas (SOCAT

    Directory of Open Access Journals (Sweden)

    B. Pfeil

    2013-04-01

    Full Text Available A well-documented, publicly available, global data set of surface ocean carbon dioxide (CO2 parameters has been called for by international groups for nearly two decades. The Surface Ocean CO2 Atlas (SOCAT project was initiated by the international marine carbon science community in 2007 with the aim of providing a comprehensive, publicly available, regularly updated, global data set of marine surface CO2, which had been subject to quality control (QC. Many additional CO2 data, not yet made public via the Carbon Dioxide Information Analysis Center (CDIAC, were retrieved from data originators, public websites and other data centres. All data were put in a uniform format following a strict protocol. Quality control was carried out according to clearly defined criteria. Regional specialists performed the quality control, using state-of-the-art web-based tools, specially developed for accomplishing this global team effort. SOCAT version 1.5 was made public in September 2011 and holds 6.3 million quality controlled surface CO2 data points from the global oceans and coastal seas, spanning four decades (1968–2007. Three types of data products are available: individual cruise files, a merged complete data set and gridded products. With the rapid expansion of marine CO2 data collection and the importance of quantifying net global oceanic CO2 uptake and its changes, sustained data synthesis and data access are priorities.

  8. Reconstituted aquaporin 1 water channels transport CO2 across membranes.

    Science.gov (United States)

    Prasad, G V; Coury, L A; Finn, F; Zeidel, M L

    1998-12-11

    Biological membranes provide selective barriers to a number of molecules and gases. However, the factors that affect permeability to gases remain unclear because of the difficulty of accurately measuring gas movements. To determine the roles of lipid composition and the aquaporin 1 (AQP1) water channel in altering CO2 flux across membranes, we developed a fluorometric assay to measure CO2 entry into vesicles. Maximal CO2 flux was approximately 1000-fold above control values with 0.5 mg/ml carbonic anhydrase. Unilamellar phospholipid vesicles of varying composition gave widely varying water permeabilities but similar CO2 permeabilities at 25 degreesC. When AQP1 purified from human red blood cells was reconstituted into proteoliposomes, however, it increased water and CO2 permeabilities markedly. Both increases were abolished with HgCl2, and the mercurial inhibition was reversible with beta-mercaptoethanol. We conclude that unlike water and small nonelectrolytes, CO2 permeation is not significantly altered by lipid bilayer composition or fluidity. AQP1 clearly serves to increase CO2 permeation, likely through the water pore; under certain circumstances, gas permeation through membranes is protein-mediated.

  9. [CO2-Concentrating Mechanism and Its Traits in Haloalkaliphilic Cyanobacteria].

    Science.gov (United States)

    Kupriyanova, E V; Samylina, O S

    2015-01-01

    Cyanobacteria are a group of oxygenic phototrophs existing for at least 3.5 Ga. Photosynthetic CO2 assimilation by cyanobacteria occurs via the Calvin cycle, with RuBisCO, its key enzyme, having very low affinity to CO2. This is due to the fact that atmospheric CO2 concentration in Archaean, when the photosynthetic apparatus evolved, was several orders higher than now. Later, in the epoch of Precambrian microbial communities, CO2 content in the atmosphere decreased drastically. Thus, present-day phototrophs, including cyanobacteria, require adaptive mechanisms for efficient photosynthesis. In cyanobacterial cells, this function is performed by the CO2-concentrating mechanism (CCM), which creates elevated CO2 concentrations in the vicinity of RuBisCO active centers, thus significantly increasing the rate of CO2 fixation in the Calvin cycle. CCM has been previously studied only for freshwater and marine cyanobacteria. We were the first to investigate CCM in haloalkaliphilic cyanobacteria from soda lakes. Extremophilic haloalkaliphilic cyanobacteria were shown to possess a well-developed CCM with the structure and functional principles similar to those of freshwater and marine strains. Analysis of available data suggests that regulation of the amount of inorganic carbon transported into the cell is probably the general CCM function under these conditions.

  10. CO2 mitigation via capture and chemical conversion in seawater.

    Science.gov (United States)

    Rau, Greg H

    2011-02-01

    A lab-scale seawater/mineral carbonate gas scrubber was found to remove up to 97% of CO(2) in a simulated flue gas stream at ambient temperature and pressure, with a large fraction of this carbon ultimately converted to dissolved calcium bicarbonate. After full equilibration with air, up to 85% of the captured carbon was retained in solution, that is, it did not degas or precipitate. Thus, above-ground CO(2) hydration and mineral carbonate scrubbing may provide a relatively simple point-source CO(2) capture and storage scheme at coastal locations. Such low-tech CO(2) mitigation could be especially relevant for retrofitting to existing power plants and for deployment in the developing world, the primary source of future CO(2) emissions. Addition of the resulting alkaline solution to the ocean may benefit marine ecosystems that are currently threatened by acidification, while also allowing the utilization of the vast potential of the sea to safely sequester anthropogenic carbon. This approach in essence hastens Nature's own very effective but slow CO(2) mitigation process; carbonate mineral weathering is a major consumer of excess atmospheric CO(2) and ocean acidity on geologic times scales.

  11. The effect of CO2 laser treatment on skin tissue.

    Science.gov (United States)

    Baleg, Sana Mohammed Anayb; Bidin, Noriah; Suan, Lau Pik; Ahmad, Muhammad Fakarruddin Sidi; Krishnan, Ganesan; Johari, Abd Rahman; Hamid, Asma

    2015-09-01

    The aim of this study was to evaluate the effects of multiple pulses on the depth of injury caused by CO2 laser in an in vivo rat model. A 10 600-nm CO2 laser was applied to rat skin, with one side of the rat dorsal skin being exposed, leaving the other side as a control. All of the various laser pulses tested led to gradual loss of epidermal thickness as well as a dramatic increase in thermal damage depth. Collagen coagulation was most effective with ten pulses of CO2 laser, while the strength of irradiated skin tissue increased as the influence of the laser increased. Fundamental laser-skin interaction effects were studied using a CO2 laser. The photodamaged areas obtained from laser interaction were recorded via couple charge device video camera and analyzed via ImageJ software. Photodamage induced by CO2 laser is due to photothermal effects, which involve burning and vaporizing mechanisms to ablate the epidermis layer. The burning area literally expands and penetrates deep into the dermis layer, subsequently causing collagen coagulation. This fundamental study shows in detail the effect of CO2 laser interaction with skin. The CO2 attributed severe burning, producing deep coagulation, and induced strength to treated skin. © 2015 Wiley Periodicals, Inc.

  12. Correlation between plant physiology and CO2 removable

    Science.gov (United States)

    Leman, A. M.; Shamsuri, Mohd Mahathir Suhaimi; Hariri, Azian; Kadir, Aeslina Abdul; Idris, Ahmad Fu'ad; Afandi, Azizi

    2017-09-01

    Certain plants that are able to live in the building are known as indoor plants. Plants have tolerance with indoor environment in order to survive. Usually these plants are able to improve indoor air quality (IAQ). Absorption of carbon dioxide (CO2) by plants is one of the indicators that plants are still alive during photosynthesis process. The possibility of plants structure (plant physiology) to affect CO2 absorption had been the concerns of former researchers. This research intends to study the significant of plant structure (leaf area, fresh weight, and dry weight) that leads to reducing the concentration of CO2 by seven plant species (Anthurium, Dumb Cane, Golden Pothos, Kadaka Fern, Prayer Plants, Spider Plants, and Syngonium). The data of CO2 reduction by plants has been obtained from previous studies. Based on results show that, the leaf area is the most contributing the significant effect to the plant absorb CO2 compare to fresh weight and dry weight. It can be prove by Pearson Correlation, where only the value of leaf area is more than 0.5 for every four conditions. This study can be conclude that the leaf area is quite plays an important role to the plant treat air from CO2, while concentration of light and CO2 will become catalytic factor for the plants improve their photosynthesis process.

  13. Tropical epiphytes in a CO 2-rich atmosphere

    Science.gov (United States)

    Monteiro, José Alberto Fernandez; Zotz, Gerhard; Körner, Christian

    2009-01-01

    We tested the effect on epiphyte growth of a doubling of pre-industrial CO 2 concentration (280 vs. 560 ppm) combined with two light (three fold) and two nutrition (ten fold) treatments under close to natural humid conditions in daylight growth cabinets over 6 months. Across co-treatments and six species, elevated CO 2 increased relative growth rates by only 6% ( p = 0.03). Although the three C3 species, on average, grew 60% faster than the three CAM species, the two groups did not significantly differ in their CO 2 response. The two Orchidaceae, Bulbophyllum (CAM) and Oncidium (C3) showed no CO 2 response, and three out of four Bromeliaceae showed a positive one: Aechmea (CAM, +32% p = 0.08), Catopsis (C3, +11% p = 0.01) and Vriesea (C3, +4% p = 0.02). In contrast, the representative of the species-rich genus Tillandsia (CAM), which grew very well under experimental conditions, showed no stimulation. On average, high light increased growth by 21% and high nutrients by 10%. Interactions between CO 2, light and nutrient treatments (low vs. high) were inconsistent across species. CO 2 responsive taxa such as Catopsis, could accelerate tropical forest dynamics and increase branch breakage, but overall, the responses to doubling CO 2 of these epiphytes was relatively small and the responses were taxa specific.

  14. CO2 - The Canary in the Energy Efficiency Coal Mine

    Science.gov (United States)

    Somssich, Peter

    2011-04-01

    While much of the discussion surrounding CO2 is focused on its role as a GHG (green house gas) and its affect on Climate Change, CO2 can also be viewed as an indicator for reductions in fossil fuel use and increased energy efficiency. Much as the canary in a mine was used to warn miners of unsafe health conditions in a mine, CO2 can be seen as allowing us to effectively track progress towards energy efficiency and sustainability. Such an effort can best be achieved by either a Carbon Tax or a Cap and Trade system which was highly effective as part of the 1992 Clean Air Act, contributing to a significant reduction of SO2 and acid rain. A similar attempt has been made using the 1997 Kyoto Protocol to reduce carbon emissions. The mechanisms of how this treaty was intended to work will be explained, and examples will be given, both in the USA and Europe, of how the protocol was used to reduce energy consumption and energy dependence, while also reducing CO2 emissions. Regardless of how strong an impact CO2 reduction may have for Climate Change issues, a reduction of CO2 is guaranteed to produce energy benefits, monetary benefits and can even enhance national security. For all of these reasons, we need the CO2 canary.

  15. Isentropic transport and the seasonal cycle amplitude of CO2

    Science.gov (United States)

    Parazoo, N.; Barnes, E. A.; Orbe, C.; Denning, A. S.

    2016-12-01

    Carbon-concentration feedbacks and carbon-climate feedbacks constitute one of the largest sources of uncertainty in future climate. Since the beginning of the modern atmospheric CO2 record, seasonal variations in CO2 have been recognized as a signal of the metabolism of land ecosystems, and quantitative attribution of changes in the seasonal cycle amplitude (SCA) of CO2 to ecosystem processes is critical for understanding and projecting carbon-climate feedbacks far into the 21st Century. Here the impact of surface carbon fluxes on the SCA of CO2 throughout the Northern Hemisphere troposphere is investigated, paying particular attention to isentropic transport across latitudes. The analysis includes both a chemical transport model GOES-Chem and an idealized tracer in a gray-radiation aquaplanet. The results of the study can be summarized by two main conclusions: (1) the SCA of CO2 roughly follows surfaces of constant potential temperature, which can explain the observed increase in SCA with latitude along pressure surfaces and (2) increasing seasonal fluxes in lower latitudes have a larger impact on the SCA of CO2 throughout most of the troposphere compared to increasing seasonal fluxes in higher latitudes. These results provide strong evidence that recently observed changes in the SCA of CO2 at high northern latitudes (poleward of 60N) are likely driven by changes in midlatitude surface fluxes, rather than changes in Arctic fluxes.

  16. DESIGN AND MECHANICAL INTEGRITY OF CO2 INJECTION WELLS

    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec

    2011-12-01

    Full Text Available Geologic Sequestration (GS is part of a process known as “carbon capture and storage (CCS” and represents the process of injecting CO2, into deep subsurface rock formations for long-term storage. For injecting of CO2 existing wells are used as well as new drilled wells. A well represents the most likely route for leakage of CO2 from geologic carbon sequestration. Maintaining mechanical integrity helps prevent the well and wellbore from becoming conduits for CO2 migration out of the injection zone. The typical components of a CO2 injection well are casing, tubing, cement, and packer. These components are relevant for maintaining mechanical integrity and ensuring CO2 does not migrate upwards from the injection zone into underground source of drinking water (USDW; therefore helping to ensure zonal isolation of the injected carbon dioxide. In order to have the safe underground storage of CO2 well integrity considerations should be present during all phases of well life including design phase, drilling, completion, injection, workover (service and abandonment. The paper describes well design, well integrity and mechanical integrity tests (MITs as a means of measuring the adequacy of the construction of the injection well and as a way to detect problems within the well system.

  17. Reinforcing carbon fixation: CO2 reduction replacing and supporting carboxylation.

    Science.gov (United States)

    Cotton, Charles Ar; Edlich-Muth, Christian; Bar-Even, Arren

    2017-08-10

    Carbon dioxide enters the biosphere via one of two mechanisms: carboxylation, in which CO2 is attached to an existing metabolite, or reduction, in which CO2 is converted to formate or carbon monoxide before further assimilation. Here, we focus on the latter mechanism which usually receives less attention. To better understand the possible advantages of the 'reduction-first' approach, we compare the two general strategies according to the kinetics of the CO2-capturing enzymes, and the resource consumption of the subsequent pathways. We show that the best CO2 reducing enzymes can compete with the best carboxylases. We further demonstrate that pathways that fix CO2 by first reducing it to formate could have an advantage over the majority of their carboxylation-only counterparts in terms of ATP-efficiency and hence biomass yield. We discuss and elaborate on the challenges of implementing 'reduction-first' pathways, including the thermodynamic barrier of CO2 reduction. We believe that pathways based on CO2 reduction are a valuable addition to nature's arsenal for capturing inorganic carbon and could provide promising metabolic solutions that have been previously overlooked. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. [CO2 sequestration coupled with industrial cultivation of microalgae].

    Science.gov (United States)

    Zhang, Feng; Xiang, Wenzhou; Xiao, Bei; Chen, Pingyuan

    2012-11-04

    In order to reduce CO2 emission and lower the cost of microalgal industrial production at the same time, a technology was developed to combine CO2 sequestration with microalgal cultivation. The technology was based on rapid pH drift and high pH adaptability of two microalgal species, Chlorococcum alkaliphilus MC-1 and Spirulina platensis. A simple structure, CO2 leakage prevention covering-box, was designed to collect CO2 escaped from culture medium when CO2 gas was injected into the culture. In the small-scale outdoor cultivation of MC-1, CO2 escaped from culture was all absorbed by culture with the help of covering-box. Results from the pilot-scale cultivation of S. platensis (HS 331) combined with the CO2 addition technology show that the cost of carbon source was remarkably reduced and deposition of CaCO3 and MgCO3 was effectively avoided. In addition, the average productivity was rather high [9.54 g/( m2 x d1)]. In the large-scale cultivation of S. platensis, the annual yield was increased by 20% and high quality product was obtained with the CO2 addition technology. In addition, 66% of NaHCO3 was saved, more than 58% of carbon cost was reduced, and about 45 tons of CO2 was sequestrated. The technology was successfully applied in industrial production of S. platensis and the cost of producing S. platensis was dramatically reduced. The study would provide new insight into carbon dioxide sequestration.

  19. Shocking Results on the Adverse Effects of CO2 Exposures

    Science.gov (United States)

    James, John T.

    2012-01-01

    Carbon dioxide (CO2) is released in large quantities from humans while they live and work in spacecraft or work outside the spacecraft during extravehicular activity (EVA). Removal of this anthropogenic pollutant requires major resources, and these resources increase dramatically as the levels of CO2 set to protect human health and performance are reduced. The current Spacecraft Maximum Allowable Concentration of CO2 aboard the ISS is 0.7% or 5.3 mmHg; however, according to Chits (mission action requests), NASA and its international partners have agreed to control CO2 levels to less than 4 mmHg. In the meantime, retrospective investigations attempting to associate crew symptoms with elevated CO2 levels over the life if the International Space Station (ISS) are underway to determine if this level is sufficient to protect against health and performance decrements. Anecdotal reports suggest that crewmembers are not able to perform complex tasks as readily in spaceflight as they were able during ground-based training. While physiological effects of CO2 have been studied for many decades, it is only recently that the effects of CO2 on higher reasoning capabilities have been studied. The initial results are shocking. For example, one study published in the respected journal Environmental Health Perspectives showed obvious adverse effects of CO2 exposures on higher reasoning at 1.9 mmHg. The implications and limitations of this study are paramount in determining future CO2 SMACs for human spaceflight, both aboard the ISS and in exploration-class missions. Key Words: carbon dioxide, spacecraft, air quality, toxic effects

  20. Does Elevated CO2 Alter Silica Uptake in Trees?

    Directory of Open Access Journals (Sweden)

    Robinson W. Fulweiler

    2015-01-01

    Full Text Available Human activities have greatly altered global carbon (C and N (N cycling. In fact, atmospheric concentrations of carbon dioxide (CO2 have increased 40% over the last century and the amount of N cycling in the biosphere has more than doubled. In an effort to understand how plants will respond to continued global carbon dioxide fertilization, long-term free-air CO2 enrichment (FACE experiments have been conducted at sites around the globe. Here we examine how atmospheric CO2 enrichment and N fertilization affects the uptake of silicon (Si in the Duke Forest, North Carolina, a stand dominated by Pinus taeda (loblolly pine, and five hardwood species. Specifically, we measured foliar biogenic silica (BSi concentrations in five deciduous and one coniferous species across three treatments: CO2 enrichment, N enrichment, and N and CO2 enrichment. We found no consistent trends in foliar Si concentration under elevated CO2, N fertilization, or combined elevated CO2 and N fertilization. However, two-thirds of the tree species studied here have Si foliar concentrations greater than well-known Si accumulators, such as grasses. Based on net primary production values and aboveground Si concentrations in these trees, we calculated forest Si uptake rates under control and elevated CO2 concentrations. Due largely to increased primary production, elevated CO2 enhanced the magnitude of Si uptake between 20% and 26%, likely intensifying the terrestrial silica pump. This uptake of Si by forests has important implications for Si export from terrestrial systems, with the potential to impact C sequestration and higher trophic levels in downstream ecosystems.