Sample records for estimate co2 storage

  1. Cost implications of uncertainty in CO2 storage resource estimates: A review (United States)

    Anderson, Steven T.


    Carbon capture from stationary sources and geologic storage of carbon dioxide (CO2) is an important option to include in strategies to mitigate greenhouse gas emissions. However, the potential costs of commercial-scale CO2 storage are not well constrained, stemming from the inherent uncertainty in storage resource estimates coupled with a lack of detailed estimates of the infrastructure needed to access those resources. Storage resource estimates are highly dependent on storage efficiency values or storage coefficients, which are calculated based on ranges of uncertain geological and physical reservoir parameters. If dynamic factors (such as variability in storage efficiencies, pressure interference, and acceptable injection rates over time), reservoir pressure limitations, boundaries on migration of CO2, consideration of closed or semi-closed saline reservoir systems, and other possible constraints on the technically accessible CO2 storage resource (TASR) are accounted for, it is likely that only a fraction of the TASR could be available without incurring significant additional costs. Although storage resource estimates typically assume that any issues with pressure buildup due to CO2 injection will be mitigated by reservoir pressure management, estimates of the costs of CO2 storage generally do not include the costs of active pressure management. Production of saline waters (brines) could be essential to increasing the dynamic storage capacity of most reservoirs, but including the costs of this critical method of reservoir pressure management could increase current estimates of the costs of CO2 storage by two times, or more. Even without considering the implications for reservoir pressure management, geologic uncertainty can significantly impact CO2 storage capacities and costs, and contribute to uncertainty in carbon capture and storage (CCS) systems. Given the current state of available information and the scarcity of (data from) long-term commercial-scale CO2

  2. CO2 capture, transport, storage and utilisation

    NARCIS (Netherlands)

    Brouwer, J.H.


    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

  3. Monitoring Options for CO2 Storage

    NARCIS (Netherlands)

    Arts, R.; Winthaegen, P.


    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

  4. Classification of CO2 Geologic Storage: Resource and Capacity (United States)

    Frailey, S.M.; Finley, R.J.


    The use of the term capacity to describe possible geologic storage implies a realistic or likely volume of CO2 to be sequestered. Poor data quantity and quality may lead to very high uncertainty in the storage estimate. Use of the term "storage resource" alleviates the implied certainty of the term "storage capacity". This is especially important to non- scientists (e.g. policy makers) because "capacity" is commonly used to describe the very specific and more certain quantities such as volume of a gas tank or a hotel's overnight guest limit. Resource is a term used in the classification of oil and gas accumulations to infer lesser certainty in the commercial production of oil and gas. Likewise for CO2 sequestration, a suspected porous and permeable zone can be classified as a resource, but capacity can only be estimated after a well is drilled into the formation and a relatively higher degree of economic and regulatory certainty is established. Storage capacity estimates are lower risk or higher certainty compared to storage resource estimates. In the oil and gas industry, prospective resource and contingent resource are used for estimates with less data and certainty. Oil and gas reserves are classified as Proved and Unproved, and by analogy, capacity can be classified similarly. The highest degree of certainty for an oil or gas accumulation is Proved, Developed Producing (PDP) Reserves. For CO2 sequestration this could be Proved Developed Injecting (PDI) Capacity. A geologic sequestration storage classification system is developed by analogy to that used by the oil and gas industry. When a CO2 sequestration industry emerges, storage resource and capacity estimates will be considered a company asset and consequently regulated by the Securities and Exchange Commission. Additionally, storage accounting and auditing protocols will be required to confirm projected storage estimates and assignment of credits from actual injection. An example illustrates the use of

  5. The estimation of CO2 storage potential of gas-bearing shale complex at the early stage of reservoir characterization: the case of Baltic Basin (Poland). (United States)

    Wójcicki, Adam; Jarosiński, Marek


    For the stage of shale gas production, like in the USA, prediction of the CO2 storage potential in shale reservoir can be performed by dynamic modeling. We have made an attempt to estimate this potential at an early stage of shale gas exploration in the Lower Paleozoic Baltic Basin, based on data from 3,800 m deep vertical well (without hydraulic fracking stimulation), supplemented with additional information from neighboring boreholes. Such an attempt makes a sense as a first guess forecast for company that explores a new basin. In our approach, the storage capacity is build by: (1) sorption potential of organic matter, (2) open pore space and (3) potential fracture space. the sequence. our estimation is done for 120 m long shale sequence including three shale intervals enriched with organic mater. Such an interval is possible to be fracked from a single horizontal borehole as known from hydraulic fracture treatment in the other boreholes in this region. The potential for adsorbed CO2 is determined from Langmuir isotherm parameters taken from laboratory measurements in case of both CH4 and CO2 adsorption, as well as shale density and volume. CO2 has approximately three times higher sorption capacity than methane to the organic matter contained in the Baltic Basin shales. Finally, due to low permeability of shale we adopt the common assumption for the USA shale basins that the CO2 will be able to reach effectively only 10% of theoretical total sorption volume. The pore space capacity was estimated by utilizing results of laboratory measurements of dynamic capacity for pores bigger than 10 nm. It is assumed for smaller pores adsorption prevails over free gas. Similarly to solution for sorption, we have assumed that only 10 % of the tight pore space will be reached by CO2. For fracture space we have considered separately natural (tectonic-origin) and technological (potentially produced by hydraulic fracturing treatment) fractures. From fracture density profile and


    Directory of Open Access Journals (Sweden)

    Marija Podbojec


    Full Text Available A preliminary assessment of the capacity of regional geological storage in the western part of the Sava Depression was based on data obtained from several deep exploration wells. The Poljana Sandstones represent a regional deep sandstone body, in most parts saturated with water, with promising underground facilities for the storage of CO₂ in the study area. Poljana Sandstones (member of Kloštar-Ivanić Formation bounded between E-log markers Rνand Z' have favourable petrophysical properties and are situated at reasonable depths. According to previous investigations, at depths greater than 800 meters supercritical conditions of temperature and pressure CO₂ are achieved, which ensures easy and safe injection into storage underground facilities. For the creation of a model in Petrel software, various data was used, including the distribution of CO₂ density, porosity, effective thickness and the relative depth of sandstone. Spatial distribution of porosity was made regarding neutron porosity logs. The most important parameter in the estimate of storage capacity is effective thickness, defined by the interval between E–log markers Rν and Z’. Hence, the effective thickness was used for top and bottom surface of sandstones. Density of CO₂ was created according to their spatial distribution regarding the depth and the temperature. The capacity of CO2 storage was calculated by the volumetric method. The use of a calculated Petrel model can subsequently determine the amount of CO₂ storage in the underground facilities of the study area.

  7. Public Acceptance for Geological CO2-Storage (United States)

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


    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

  8. Gas condensate reservoir characterisation for CO2 geological storage (United States)

    Ivakhnenko, A. P.


    calculations demonstrate that injection of produced and additional gas (CO2 and sour gases) is economically viable and ecologically safe. Gas injection monitoring using surface injection well head pressures and measured injected volumes demonstrates a highly effective gas injection process. Injection well head pressure response shows no increase, indicating absence of compartmentalization close to the near well bore gas injection region in reservoir. And injector pulse study shows interconnectivity across the injection region highlighting good quality reservoir across the potential CO2 injection zones. Preliminary CO2 storage potential was also estimated for this type of geological site.

  9. Large-scale CO2 storage — Is it feasible?

    Directory of Open Access Journals (Sweden)

    Johansen H.


    Full Text Available CCS is generally estimated to have to account for about 20% of the reduction of CO2 emissions to the atmosphere. This paper focuses on the technical aspects of CO2 storage, even if the CCS challenge is equally dependent upon finding viable international solutions to a wide range of economic, political and cultural issues. It has already been demonstrated that it is technically possible to store adequate amounts of CO2 in the subsurface (Sleipner, InSalah, Snøhvit. The large-scale storage challenge (several Gigatons of CO2 per year is more an issue of minimizing cost without compromising safety, and of making international regulations.The storage challenge may be split into 4 main parts: 1 finding reservoirs with adequate storage capacity, 2 make sure that the sealing capacity above the reservoir is sufficient, 3 build the infrastructure for transport, drilling and injection, and 4 set up and perform the necessary monitoring activities. More than 150 years of worldwide experience from the production of oil and gas is an important source of competence for CO2 storage. The storage challenge is however different in three important aspects: 1 the storage activity results in pressure increase in the subsurface, 2 there is no production of fluids that give important feedback on reservoir performance, and 3 the monitoring requirement will have to extend for a much longer time into the future than what is needed during oil and gas production. An important property of CO2 is that its behaviour in the subsurface is significantly different from that of oil and gas. CO2 in contact with water is reactive and corrosive, and may impose great damage on both man-made and natural materials, if proper precautions are not executed. On the other hand, the long-term effect of most of these reactions is that a large amount of CO2 will become immobilized and permanently stored as solid carbonate minerals. The reduced opportunity for direct monitoring of fluid samples

  10. Large-scale CO2 storage — Is it feasible? (United States)

    Johansen, H.


    CCS is generally estimated to have to account for about 20% of the reduction of CO2 emissions to the atmosphere. This paper focuses on the technical aspects of CO2 storage, even if the CCS challenge is equally dependent upon finding viable international solutions to a wide range of economic, political and cultural issues. It has already been demonstrated that it is technically possible to store adequate amounts of CO2 in the subsurface (Sleipner, InSalah, Snøhvit). The large-scale storage challenge (several Gigatons of CO2 per year) is more an issue of minimizing cost without compromising safety, and of making international regulations.The storage challenge may be split into 4 main parts: 1) finding reservoirs with adequate storage capacity, 2) make sure that the sealing capacity above the reservoir is sufficient, 3) build the infrastructure for transport, drilling and injection, and 4) set up and perform the necessary monitoring activities. More than 150 years of worldwide experience from the production of oil and gas is an important source of competence for CO2 storage. The storage challenge is however different in three important aspects: 1) the storage activity results in pressure increase in the subsurface, 2) there is no production of fluids that give important feedback on reservoir performance, and 3) the monitoring requirement will have to extend for a much longer time into the future than what is needed during oil and gas production. An important property of CO2 is that its behaviour in the subsurface is significantly different from that of oil and gas. CO2 in contact with water is reactive and corrosive, and may impose great damage on both man-made and natural materials, if proper precautions are not executed. On the other hand, the long-term effect of most of these reactions is that a large amount of CO2 will become immobilized and permanently stored as solid carbonate minerals. The reduced opportunity for direct monitoring of fluid samples close to the

  11. CO2 Storage related Groundwater Impacts and Protection (United States)

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


    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.

  12. Impacts of fluvial sedimentary heterogeneities on CO2 storage performance (United States)

    Issautier, B. H.; Viseur, S.; Audigane, P. D.


    The heterogeneity of fluvial systems is a key parameter in sedimentology due to the associated impacts on flow performance. In a broader context, fluvial reservoirs are now targets for CO2 storage projects in several sedimentary basins (Paris Basin, North German Basin), thus calling for detailed characterization of reservoir behaviour and capacity. Fluvial reservoirs are a complex layout of highly heterogeneous sedimentary bodies with varying connectivity, depending on the sedimentary history of the system. Reservoir characterization must determine (a) the nature and dimension of the sedimentary bodies, and (b) the connectivity drivers and their evolution throughout the stratigraphic succession. Based on reservoir characterization, geological modelling must account for this information and can be used as a predictive tool for capacity estimation. Flow simulation, however, describes the reservoir behaviour with respect to CO2 injection. The present work focuses on fluvial reservoir performance and was carried out as part of a PhD (2008-2011) dedicated to the impact of sedimentary heterogeneity on CO2 storage performance. The work comprises three steps: ? Reservoir characterization based on detailed fieldwork (sedimentology and sequence stratigraphy) carried out in Central Arabia on the Minjur Sandstone. Twelve depositional environments and their associated heterogeneity are identified, and their layout is presented in a high-resolution sequence stratigraphy analysis. This step is summed up in a 3D geological model. ? Conceptual modelling based on this field data, using gOcad software and an in-house python code. The purpose was to study, for a given architecture, the impact of sedimentary heterogeneity on storage capacity estimations using two models: one with heterogeneity within the sedimentary fill (model A); the other without heterogeneity within the sedimentary fill (model B). A workflow was designed to estimate and compare the storage capacities for a series

  13. The Value of CO2-Geothermal Bulk Energy Storage to Reducing CO2 Emissions Compared to Conventional Bulk Energy Storage Technologies (United States)

    Ogland-Hand, J.; Bielicki, J. M.; Buscheck, T. A.


    Sedimentary basin geothermal resources and CO2 that is captured from large point sources can be used for bulk energy storage (BES) in order to accommodate higher penetration and utilization of variable renewable energy resources. Excess energy is stored by pressurizing and injecting CO2 into deep, porous, and permeable aquifers that are ubiquitous throughout the United States. When electricity demand exceeds supply, some of the pressurized and geothermally-heated CO2 can be produced and used to generate electricity. This CO2-BES approach reduces CO2 emissions directly by storing CO2 and indirectly by using some of that CO2 to time-shift over-generation and displace CO2 emissions from fossil-fueled power plants that would have otherwise provided electricity. As such, CO2-BES may create more value to regional electricity systems than conventional pumped hydro energy storage (PHES) or compressed air energy storage (CAES) approaches that may only create value by time-shifting energy and indirectly reducing CO2 emissions. We developed and implemented a method to estimate the value that BES has to reducing CO2 emissions from regional electricity systems. The method minimizes the dispatch of electricity system components to meet exogenous demand subject to various CO2 prices, so that the value of CO2 emissions reductions can be estimated. We applied this method to estimate the performance and value of CO2-BES, PHES, and CAES within real data for electricity systems in California and Texas over the course of a full year to account for seasonal fluctuations in electricity demand and variable renewable resource availability. Our results suggest that the value of CO2-BES to reducing CO2 emissions may be as much as twice that of PHES or CAES and thus CO2-BES may be a more favorable approach to energy storage in regional electricity systems, especially those where the topography is not amenable to PHES or the subsurface is not amenable to CAES.

  14. Key site abandonment steps in CO2 storage (United States)

    Kühn, M.; Wipki, M.; Durucan, S.; Deflandre, J.-P.; Lüth, S.; Wollenweber, J.; Chadwick, A.; Böhm, G.


    CO2CARE is an EU funded project within FP7-research, which started in January 2011 with a funding period of three years. The project objectives will be achieved through an international consortium consisting of 23 partners from Europe, USA, Canada, Japan, and Australia, belonging to universities, research institutes, and energy companies. According to the EC Guidance Document 3, the lifetime of a CO2 storage site can be generally subdivided into 6 phases: 1. assessment, 2. characterisation, 3. development, 4. operation, 5. post-closure/pre-transfer, and 6. post transfer. CO2CARE deals with phases 5 and 6. The main goals of the project are closely linked to the three high-level requirements of the EU Directive 2009/31/EC, Article 18 for CO2 storage which are: (i) absence of any detectable leakage, (ii) conformity of actual behaviour of the injected CO2 with the modelled behaviour, and (iii) the storage site is evolving towards a situation of long-term stability. These criteria have to be fulfilled prior to subsequent transfer of responsibility to the competent authorities, typically 20 or 30 years after site closure. CO2CARE aims to formulate robust procedures for site abandonment which will meet the regulatory requirements and ensure long-term integrity of the storage complex. We present key results from the first year of the project via a report on international regulatory requirements on CO2 geological storage and site abandonment that includes a general overview on the current state-of-the art in abandonment methodologies in the oil and gas industry worldwide. Due to the long time-frames involved in CO2 storage (in the range of several thousands of years), the behaviour of a system with respect to, for example, long-term well stability can be demonstrated only by using long-term predictive modelling tools to study potential leakage pathways. Trapping mechanisms for CO2 are of high interest concerning a quantitative estimation of physically captured, capillary

  15. Determining CO2 storage potential during miscible CO2 enhanced oil recovery: Noble gas and stable isotope tracers (United States)

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


    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

  16. Comparison of Dry Gas Seasonal Storage with CO2 Storage and Re-Use Potential


    Killerud, Marie


    To make large-scale CO2 storage economic, many groups have proposed using CO2in EOR projects to create value for CO2 storage. However, CO2 EOR projectsgenerally require a large and variable supply of CO2 and consequently may requiretemporary storage of CO2 in geological formations. In order to store CO2 atoffshore sites as a source for CO2 EOR projects, the CO2 needs to be extractedfrom a storage site to a certain extent. Alternatively, CO2 EOR projects maybe developed alongside saline aquife...

  17. Techno-Economic Assessment of Four CO2 Storage Sites

    Directory of Open Access Journals (Sweden)

    Gruson J.-F.


    Full Text Available Carbon Capture and Storage (CCS should be a key technology in order to achieve a decline in the CO2 emissions intensity of the power sector and other intensive industry, but this potential deployment could be restricted by cost issues as the International Energy Agency (IEA in their last projections (World Energy Outlook 2013 has considered only around 1% of global fossil fuel-fired power plants could be equipped with CCS by 2035. The SiteChar project funded by 7th Framework Programme of European Commission gives the opportunity to evaluate the most influential parameters of techno-economic evaluations of four feasible European projects for CO2 geological storage located onshore and offshore and related to aquifer storage or oil and gas reservoirs, at different stages of characterization. Four potential CO2 storage sites have been assessed in terms of storage costs per tonne of CO2 permanently stored (equivalent cost based. They are located offshore UK, onshore Denmark, offshore Norway and offshore Italy. The four SiteChar techno-economic evaluations confirm it is not possible to derive any meaningful average cost for a CO2 storage site. The results demonstrate that the structure of costs for a project is heterogeneous and the storage cost is consequently site dependent. The strategy of the site development is fundamental, the technical choices such as the timing, rate and duration of injection are also important. The way monitoring is managed, using observation wells and logging has a strong impact on the estimated monitoring costs. Options to lower monitoring costs, such as permanent surveys, exist and should be further investigated. Table 1 below summarizes the cost range in Euro per tonne (Discount Rate (DR at 8% for the different sites, which illustrates the various orders of magnitude due to the specificities of each site. These figures have how to be considered with care. In particular the Italian and Norwegian sites present very specific

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

    Energy Technology Data Exchange (ETDEWEB)



    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.

  19. 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.


    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

  20. Behavior of CO2/water flow in porous media for CO2geological storage. (United States)

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


    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.

  1. Corrosion studies on casing steel in CO2 storage environments

    NARCIS (Netherlands)

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


    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)

  2. System-level modeling for geological storage of CO2


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


    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...

  3. Simulating Remediation of CO2 Leakage from Geological Storage Sites (United States)

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


    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.

  4. Potential environmental impacts of offshore UK geological CO2 storage (United States)

    Carruthers, Kit; Wilkinson, Mark; Butler, Ian B.


    Geological carbon dioxide storage in the United Kingdom (UK) will almost certainly be entirely offshore, with storage for over 100 years' worth of UK CO2 output from industry and power generation in offshore depleted hydrocarbon fields and sandstone formations. Storage capacity can be limited by the increase in formation water pressure upon CO2 injection, therefore removal and disposal of formation waters ('produced waters') can control formation water pressures, and increase CO2 storage capacity. Formation waters could also be produced during CO2-Enhanced Oil Recovery (CO2-EOR). The precedent from current UK North Sea hydrocarbon extraction is to 'overboard' produced waters into the ocean, under current regulations. However, laboratory and field scale studies, with an emphasis on the effects on onshore shallow potable groundwaters, have shown that CO2 dissolution in formation waters during injection and storage acidifies the waters and promotes mobilisation from the reservoir sandstones of major and trace elements into solution, including heavy metals. Eight of these elements are specifically identified in the UK as potentially hazardous to the marine environment (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn). A comparison was made between the concentrations of these eight trace elements in the results of laboratory batch leaching experiments of reservoir rock in CO2-rich saline solutions and overboarded waters from current offshore UK hydrocarbon production. This showed that, taking the North Sea as a whole, the experimental results fall within the range of concentrations of current oil and gas activities. However, on a field-by-field basis, concentrations may be enhanced with CO2 storage, such that they are higher than waters normally produced from a particular field. Lead, nickel and zinc showed the greatest concentration increases in the experiments with the addition of CO2, with the other five elements of interest not showing any strong trends with respect to enhanced CO2

  5. Rapid solubility and mineral storage of CO2 in basalt

    DEFF Research Database (Denmark)

    Gislason, Sigurdur R.; Broecker, W.S.; Gunnlaugsson, E.


    rich in divalent metal cations such as basalts and ultra-mafic rocks. We have demonstrated the dissolution of CO2 into water during its injection into basalt leading to its geologic solubility storage in less than five minutes and potential geologic mineral storage within few years after injection [1...

  6. High storage rates of anthropogenic CO_{2} in the Indian sector of the Southern Ocean (United States)

    Murata, Akihiko; Kumamoto, Yu-ichiro; Sasaki, Ken-ichi


    Using high-quality data for CO2-system and related properties collected 17 years apart through international observation programs, we examined decadal-scale increases of anthropogenic CO2 along a zonal section at nominal 62˚ S ranging from 30˚ E to 160˚ E in the Indian sector of the Southern Ocean. In contrast to previous studies, increases of anthropogenic CO2 were largest (> 9.0 μmol kg-1) in Antarctic Bottom Water, where little storage of anthropogenic CO2 has been reported. Significant increases of anthropogenic CO2 in bottom and/or deep waters were detected through the section, although they became reduced in magnitude and depth range west of 110˚ E. Vertical distributions of anthropogenic CO2 showed significant positive correlations with decadal-scale changes in CFC-12, a proxy of circulation and ventilation, meaning that the distributions were mainly controlled by physical processes. Comparison of increases of anthropogenic CO2 between calculation methods with and without total alkalinity presented differences of increases of anthropogenic CO2west of 50˚ E. This is probably because decreases in production of particulate inorganic carbons in the Southern Ocean. The highest storage rate of anthropogenic CO2 was estimated to be 1.1 ± 0.6 mol m-2 a-1 at longitudes 130˚ -160˚ E. The results highlight storage rates higher than ever reported in the Southern Ocean, where very low storage of anthropogenic CO2 has been evidenced.

  7. CO2 Capture and Storage in Coal Gasification Projects (United States)

    Rao, Anand B.; Phadke, Pranav C.


    concerns about climate change problem. Carbon Capture and Storage (CCS) is being considered as a promising carbon mitigation technology, especially for large point sources such as coal power plants. Gasification of coal helps in better utilization of this resource offering multiple advantages such as pollution prevention, product flexibility (syngas and hydrogen) and higher efficiency (combined cycle). It also enables the capture of CO2 prior to the combustion, from the fuel gas mixture, at relatively lesser cost as compared to the post-combustion CO2 capture. CCS in gasification projects is considered as a promising technology for cost-effective carbon mitigation. Although many projects (power and non-power) have been announced internationally, very few large-scale projects have actually come up. This paper looks at the various aspects of CCS applications in gasification projects, including the technical feasibility and economic viability and discusses an Indian perspective. Impacts of including CCS in gasification projects (e.g. IGCC plants) have been assessed using a simulation tool. Integrated Environmental Control Model (IECM) - a modelling framework to simulate power plants - has been used to estimate the implications of adding CCS units in IGCC plants, on their performance and costs.

  8. Experimental Investigations into CO2 Interactions with Injection Well Infrastructure for CO2 Storage (United States)

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


    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

  9. Methods to Assess Geological CO2 Storage Capacity: Status and Best Practice

    Energy Technology Data Exchange (ETDEWEB)



    To understand the emission reduction potential of carbon capture and storage (CCS), decision makers need to understand the amount of CO2 that can be safely stored in the subsurface and the geographical distribution of storage resources. Estimates of storage resources need to be made using reliable and consistent methods. Previous estimates of CO2 storage potential for a range of countries and regions have been based on a variety of methodologies resulting in a correspondingly wide range of estimates. Consequently, there has been uncertainty about which of the methodologies were most appropriate in given settings, and whether the estimates produced by these methods were useful to policy makers trying to determine the appropriate role of CCS. In 2011, the IEA convened two workshops which brought together experts for six national surveys organisations to review CO2 storage assessment methodologies and make recommendations on how to harmonise CO2 storage estimates worldwide. This report presents the findings of these workshops and an internationally shared guideline for quantifying CO2 storage resources.

  10. Effect of Mineral Dissolution/Precipitation and CO2 Exsolution on CO2 transport in Geological Carbon Storage. (United States)

    Xu, Ruina; Li, Rong; Ma, Jin; He, Di; Jiang, Peixue


    Geological carbon sequestration (GCS) in deep saline aquifers is an effective means for storing carbon dioxide to address global climate change. As the time after injection increases, the safety of storage increases as the CO2 transforms from a separate phase to CO2(aq) and HCO3(-) by dissolution and then to carbonates by mineral dissolution. However, subsequent depressurization could lead to dissolved CO2(aq) escaping from the formation water and creating a new separate phase which may reduce the GCS system safety. The mineral dissolution and the CO2 exsolution and mineral precipitation during depressurization change the morphology, porosity, and permeability of the porous rock medium, which then affects the two-phase flow of the CO2 and formation water. A better understanding of these effects on the CO2-water two-phase flow will improve predictions of the long-term CO2 storage reliability, especially the impact of depressurization on the long-term stability. In this Account, we summarize our recent work on the effect of CO2 exsolution and mineral dissolution/precipitation on CO2 transport in GCS reservoirs. We place emphasis on understanding the behavior and transformation of the carbon components in the reservoir, including CO2(sc/g), CO2(aq), HCO3(-), and carbonate minerals (calcite and dolomite), highlight their transport and mobility by coupled geochemical and two-phase flow processes, and consider the implications of these transport mechanisms on estimates of the long-term safety of GCS. We describe experimental and numerical pore- and core-scale methods used in our lab in conjunction with industrial and international partners to investigate these effects. Experimental results show how mineral dissolution affects permeability, capillary pressure, and relative permeability, which are important phenomena affecting the input parameters for reservoir flow modeling. The porosity and the absolute permeability increase when CO2 dissolved water is continuously

  11. CO2 Storage Capacity for Multi-Well Pads Scheme in Depleted Shale Gas Reservoirs

    Directory of Open Access Journals (Sweden)

    Zhan Meng


    Full Text Available As a promising technology to improve shale gas (SG recovery and CO2 storage capacity, the multi-well pads (MWPs scheme has gained more and more attention. The semi-analytical pressure-buildup method has been used to estimate CO2 storage capacity. It focuses on single multi-fractured horizontal wells (SMFHWs and does not consider multi-well pressure interference (MWPI induced by the MWPs scheme. This severely limits the application of this method as incidences of multi-well pressure interference have been widely reported. This paper proposed a new methodology to optimize the injection strategy of the MWPs scheme and maximize CO2 storage capacity. The new method implements numerical discretization, the superposition theory, Gauss elimination, and the Stehfest numerical algorithm to obtain pressure-buildup solutions for the MWPs scheme. The solution by the new method was validated with numerical simulation and pressure-buildup curves were generated to identify MWPI. Using the new method, we observed that the fracture number and fracture half-length have a positive influence on CO2 storage capacity. Both can be approximately related to the CO2 storage capacity by a linear correlation. For a given injection pressure, there is an optimal fracture number; the bigger the limited injection pressure, the smaller the optimal fracture number. Stress sensitivity has positive influences on CO2 storage capacity, thus extending the injection period would improve CO2 storage capacity. This work gains some insights into the CO2 storage capacity of the MWPs scheme in depleted SG reservoirs, and provides considerable guidance on injection strategies to maximize CO2 storage capacity in depleted SG reservoirs.

  12. CO2 Storage Feasibility: A Workflow for Site Characterisation

    Directory of Open Access Journals (Sweden)

    Nepveu Manuel


    Full Text Available In this paper, we present an overview of the SiteChar workflow model for site characterisation and assessment for CO2 storage. Site characterisation and assessment is required when permits are requested from the legal authorities in the process of starting a CO2 storage process at a given site. The goal is to assess whether a proposed CO2 storage site can indeed be used for permanent storage while meeting the safety requirements demanded by the European Commission (EC Storage Directive (9, Storage Directive 2009/31/EC. Many issues have to be scrutinised, and the workflow presented here is put forward to help efficiently organise this complex task. Three issues are highlighted: communication within the working team and with the authorities; interdependencies in the workflow and feedback loops; and the risk-based character of the workflow. A general overview (helicopter view of the workflow is given; the issues involved in communication and the risk assessment process are described in more detail. The workflow as described has been tested within the SiteChar project on five potential storage sites throughout Europe. This resulted in a list of key aspects of site characterisation which can help prepare and focus new site characterisation studies.

  13. Mass balance monitoring of geological CO2 storage with a superconducting gravimeter - A case study (United States)

    Kim, Jeong Woo; Neumeyer, Juergen; Kao, Ricky; Kabirzadeh, Hojjat


    Although monitoring of geological carbon dioxide (CO2) storage is possible with a number of geophysical and geodetic techniques (e.g., seismic survey), gravimetric monitoring is known to be the most accurate method for measuring total mass changes. Therefore, it can be used for detection of storage pore space content changes and migration of CO2 plumes. A superconducting gravimeter (SG) installed on the Earth's surface provides precise and continuous records of gravity variations over time for periods from minutes to decades, which are required for monitoring subsurface CO2 storage. Due to the fact that gravimeter records combine the gravity effects of surface displacement and subsurface mass change, these two effects must be separated properly for observing CO2 mass balance. The Newtonian attraction gravity effect of stored CO2 is modeled as a function of reservoir depth and CO2 mass for different locations of the gravimeter over the reservoir. The gravity effect of the surface deformation is considered according to the modeled and measured displacement above the CO2 reservoir at the gravimeter's position. For estimation of the detection threshold, an assessment is carried out for the gravity corrections, which must be subtracted from the raw gravity data before obtaining the gravity signal of the stored CO2. A CO2 signal larger than about 0.5 μGal can be detected with an SG's continuous recordings. A measured gravity profile along the reservoir can support the continuous measurements. For providing objective evidence of a CO2 stored gravity signal, real measured raw SG gravity data of the MunGyung site in Korea were superimposed with an artificial uniformly continuous gravity signal up to 1.7 μGal, representing a gravity signal from a CO2 storage site with increasing injections up to about 105 kt at a depth of 600 m. These data were analyzed, and the CO2 storage signal could be clearly identified.

  14. European resource assessment for geothermal energy and CO2 storage

    NARCIS (Netherlands)

    Wees, J.D. van; Neele, F.


    Geothermal Energy and CO2 Capture and Storage (CCS) are both considered major contributors to the global energy transition. Their success critically depends on subsurface resource quality, which in turn depends on specific subsurface parameters. For CCS and Geothermal Energy these in some respect

  15. Risk Assessment Methodology for CO2 Storage: The Scenario Approach

    NARCIS (Netherlands)

    Wildenborg, A.F.B.; Leijnse, A.L.; Kreft, E.; Nepveu, M.N.; Obdam, A.N.M.; Orlic, B.; Wipfler, E.L.; Grift, B. van der; Kesteren, W. van; Gaus, I.; Czernichowski-Lauriol, I.; Torfs, P.; Wójcik, R.


    This chapter introduces a "scenario approach," which is used as a methodology for the long-term safety assessment of underground CO2 storage and to demonstrate its applicability in an example of safety assessment. This developed methodology consists of three main parts-scenario analysis, model

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

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


    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. CO 2 breakthrough—Caprock sealing efficiency and integrity for carbon geological storage

    KAUST Repository

    Espinoza, D. Nicolas


    Small pores in high specific surface clay-rich caprocks give rise to high capillary entry pressures and high viscous drag that hinder the migration of buoyant carbon dioxide CO2. We measured the breakthrough pressure and ensuing CO2 permeability through sediment plugs prepared with sand, silt, kaolinite and smectite, and monitored their volumetric deformation using high-pressure oedometer cells. The data show water expulsion and volumetric contraction prior to CO2 breakthrough, followed by preferential CO2 flow thereafter. Our experimental results and data gathered from previous studies highlight the inverse relationship between breakthrough pressure and pore size, as anticipated by Laplace’s equation. In terms of macro-scale parameters, the breakthrough pressure increases as the sediment specific surface increases and the porosity decreases. The breakthrough pressure is usually lower than the values predicted with average pore size estimations; it can reach ∼6.2MPa in argillaceous formations, and 11.2MPa in evaporites. The CO2 permeability after breakthrough is significantly lower than the absolute permeability, but it may increase in time due to water displacement and desiccation. Leakage will be advection-controlled once percolation takes place at most storage sites currently being considered. Diffusive and advective CO2 leaks through non-fractured caprocks will be minor and will not compromise the storage capacity at CO2 injection sites. The “sealing number” and the “stability number” combine the initial fluid pressure, the buoyant pressure caused by the CO2 plume, the capillary breakthrough pressure of the caprock, and the stress conditions at the reservoir depth; these two numbers provide a rapid assessment of potential storage sites. Unexpected CO2 migration patterns emerge due to the inherent spatial variability and structural discontinuities in geological formations; sites with redundant seal layers should be sought for the safe and long

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

    Directory of Open Access Journals (Sweden)

    S. Basu


    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.

  19. Geological storage of CO2 within the oceanic crust by gravitational trapping (United States)

    Marieni, Chiara; Henstock, Timothy J.; Teagle, Damon A. H.


    rise of atmospheric carbon dioxide (CO2) principally due to the burning of fossil fuels is a key driver of anthropogenic climate change. Mitigation strategies include improved efficiency, using renewable energy, and capture and long-term sequestration of CO2. Most sequestration research considers CO2 injection into deep saline aquifers or depleted hydrocarbon reservoirs. Unconventional suggestions include CO2 storage in the porous volcanic lavas of uppermost oceanic crust. Here we test the feasibility of injecting CO2 into deep-sea basalts and identify sites where CO2 should be both physically and gravitationally trapped. We use global databases to estimate pressure and temperature, hence density of CO2 and seawater at the sediment-basement interface. At previously suggested sites on the Juan de Fuca Plate and in the eastern equatorial Pacific Ocean, CO2 is gravitationally unstable. However, we identify five sediment-covered regions where CO2 is denser than seawater, each sufficient for several centuries of anthropogenic CO2 emissions.

  20. Estimation of CO2 Transport Costs in South Korea Using a Techno-Economic Model

    Directory of Open Access Journals (Sweden)

    Kwangu Kang


    Full Text Available In this study, a techno–economic model was used to calculate the costs of CO2 transport and specify the major equipment required for transport in order to demonstrate and implement CO2 sequestration in the offshore sediments of South Korea. First, three different carbon capture and storage demonstration scenarios were set up involving the use of three CO2 capture plants and one offshore storage site. Each transport scenario considered both the pipeline transport and ship transport options. The temperature and pressure conditions of CO2 in each transport stage were determined from engineering and economic viewpoints, and the corresponding specifications and equipment costs were calculated. The transport costs for a 1 MtCO2/year transport rate were estimated to be US$33/tCO2 and US$28/tCO2 for a pipeline transport of ~530 km and ship transport of ~724 km, respectively. Through the economies of scale effect, the pipeline and ship transport costs for a transport rate of 3 MtCO2/year were reduced to approximately US$21/tCO2 and US$23/tCO2, respectively. A CO2 hub terminal did not significantly reduce the cost because of the short distance from the hub to the storage site and the small number of captured sources.

  1. International Symposium on Site Characterization for CO2Geological Storage

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Chin-Fu


    Several technological options have been proposed to stabilize atmospheric concentrations of CO{sub 2}. One proposed remedy is to separate and capture CO{sub 2} from fossil-fuel power plants and other stationary industrial sources and to inject the CO{sub 2} into deep subsurface formations for long-term storage and sequestration. Characterization of geologic formations for sequestration of large quantities of CO{sub 2} needs to be carefully considered to ensure that sites are suitable for long-term storage and that there will be no adverse impacts to human health or the environment. The Intergovernmental Panel on Climate Change (IPCC) Special Report on Carbon Dioxide Capture and Storage (Final Draft, October 2005) states that ''Site characterization, selection and performance prediction are crucial for successful geological storage. Before selecting a site, the geological setting must be characterized to determine if the overlying cap rock will provide an effective seal, if there is a sufficiently voluminous and permeable storage formation, and whether any abandoned or active wells will compromise the integrity of the seal. Moreover, the availability of good site characterization data is critical for the reliability of models''. This International Symposium on Site Characterization for CO{sub 2} Geological Storage (CO2SC) addresses the particular issue of site characterization and site selection related to the geologic storage of carbon dioxide. Presentations and discussions cover the various aspects associated with characterization and selection of potential CO{sub 2} storage sites, with emphasis on advances in process understanding, development of measurement methods, identification of key site features and parameters, site characterization strategies, and case studies.

  2. Case study - Dynamic pressure-limited capacity and costs of CO2 storage in the Mount Simon sandstone (United States)

    Anderson, Steven T.; Jahediesfanjani, Hossein


    Widespread deployment of carbon capture and storage (CCS) is likely necessary to be able to satisfy baseload electricity demand, to maintain diversity in the energy mix, and to achieve climate and other objectives at the lowest cost. If all of the carbon dioxide (CO2) emissions from stationary sources (such as fossil-fuel burning power plants, and other industrial plants) in the United States needed to be captured and stored, it could be possible to store only a small fraction of this CO2 in oil and natural gas reservoirs, including as a result of CO2 utilization for enhanced oil recovery. The vast majority would have to be stored in saline-filled reservoirs (Dahowski et al., 2005). Given a lack of long-term commercial-scale CCS projects, there is considerable uncertainty in the risks, dynamic capacity, and their cost implications for geologic storage of CO2. Pressure buildup in the storage reservoir is expected to be a primary source of risk associated with CO2 storage, and could severely limit CO2 injection rates (dynamic storage capacities). Most cost estimates for commercial-scale deployment of CCS estimate CO2 storage costs under assumed availability of a theoretical capacity to store tens, hundreds, or even thousands of gigatons of CO2, without considering geologic heterogeneities, pressure limitations, or the time dimension. This could lead to underestimation of the costs of CO2 storage (Anderson, 2017). This paper considers the impacts of pressure limitations and geologic heterogeneity on the dynamic CO2 storage capacity and storage (injection) costs. In the U.S. Geological Survey (USGS)’s National Assessment of Geologic CO2 Storage Resources (USGS, 2013), the mean estimate of the theoretical storage capacity in the Mount Simon Sandstone was about 94 billion metric tons of CO2. However, our results suggest that the pressure-limited capacity after 50 years of injection could be only about 4% of the theoretical geologic storage capacity in this formation

  3. CO2 Fixation into Novel CO2 Storage Materials Composed of 1,2-Ethanediamine and Ethylene Glycol Derivatives. (United States)

    Zhao, Tianxiang; Guo, Bo; Han, Limin; Zhu, Ning; Gao, Fei; Li, Qiang; Li, Lihua; Zhang, Jianbin


    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.

  4. Geological Storage of CO2. Site Selection Criteria; Almacenamiento Geologico de CO2. Criterios de Selecci0n de Emplazamientos

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, C.; Martinez, R.; Recreo, F.; Prado, P.; Campos, R.; Pelayo, M.; Losa, A. de la; Hurtado, A.; Lomba, L.; Perez del Villar, L.; Ortiz, G.; Sastre, J.; Zapatero, M. A.; Suarez, I.; Arenillas, A.


    In year 2002 the Spanish Parliament unanimously passed the ratification of the Kyoto Protocol, signed December 1997, compromising to limiting the greenhouse gas emissions increase. Later on, the Environment Ministry submitted the Spanish National Assignment Emissions Plan to the European Union and in year 2005 the Spanish Greenhouse Gas market started working, establishing taxes to pay in case of exceeding the assigned emissions limits. So, the avoided emissions of CO2 have now an economic value that is promoting new anthropogenic CO2 emissions reduction technologies. Carbon Capture and Storage (CCS) are among these new technological developments for mitigating or eliminate climate change. CO2 can be stored in geological formations such as depleted oil or gas fields, deep permeable saline water saturated formations and unmailable coal seams, among others. This report seeks to establish the selection criteria for suitable geological formations for CO2 storage in the Spanish national territory, paying attention to both the operational and performance requirements of these storage systems. The report presents the physical and chemical properties and performance of CO2 under storage conditions, the transport and reaction processes of both supercritical and gaseous CO2, and CO2 trapping mechanisms in geological formations. The main part of the report is devoted to geological criteria at watershed, site and formation scales. (Author) 100 refs.

  5. Geological Storage of CO2. Site Selection Criteria; Almacenamiento Geologico de CO2. Criterios de Seleccion de Emplazamientos

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, C.; Martinez, R.; Recreo, F.; Prado, P.; Campos, R.; Pelayo, M.; Losa, A. de la; Hurtado, A.; Lomba, L.; Perez del Villar, L.; Ortiz, G.; Sastre, J.


    In year 2002 the Spanish Parliament unanimously passed the ratification of the Kyoto Protocol, signed December 1997, compromising to limiting the greenhouse gas emissions increase. Later on, the Environment Ministry submitted the Spanish National Assignment Emissions Plan to the European Union and in year 2005 the Spanish Greenhouse Gas market started working, establishing taxes to pay in case of exceeding the assigned emissions limits. So, the avoided emissions of CO2 have now an economic value that is promoting new anthropogenic CO2 emissions reduction technologies. Carbon Capture and Storage (CCS) are among these new technological developments for mitigating or eliminate climate change. CO2 can be stored in geological formations such as depleted oil or gas fields, deep permeable saline water saturated formations and unmineable coal seams, among others. This report seeks to establish the selection criteria for suitable geological formations for CO2 storage in the Spanish national territory, paying attention to both the operational and performance requirements of these storage systems. The report presents the physical and chemical properties and performance of CO2 under storage conditions, the transport and reaction processes of both supercritical and gaseous CO2, and CO2 trapping mechanisms in geological formations. The main part of the report is devoted to geological criteria at watershed, site and formation scales. (Author) 100 ref.

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

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


    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.

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

    Directory of Open Access Journals (Sweden)

    Knut Arne Birkedal


    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.

  8. Experimental Investigation on CO2 Methanation Process for Solar Energy Storage Compared to CO2-Based Methanol Synthesis


    Castellani, Beatrice; Gambelli, Alberto Maria; Morini, Elena; Nastasi, B.; Presciutti, Andrea; Filipponi, Mirko; Nicolini, Andrea; Rossi, Federico


    The utilization of the captured CO2 as a carbon source for the production of energy storage media offers a technological solution for overcoming crucial issues in current energy systems. Solar energy production generally does not match with energy demand because of its intermittent and non-programmable nature, entailing the adoption of storage technologies. Hydrogen constitutes a chemical storage for renewable electricity if it is produced by water electrolysis and is also the key reactant fo...

  9. Health, Safety, and Environmental Screening and Ranking Frameworkfor Geologic CO2 Storage Site Selection

    Energy Technology Data Exchange (ETDEWEB)

    Oldenburg, Curtis M.


    This report describes a screening and ranking framework(SRF) developed to evaluate potential geologic carbon dioxide (CO2) storage sites on the basis of health, safety, and environmental (HSE) risk arising from possible CO2 leakage. The approach is based on the assumption that HSE risk due to CO2 leakage is dependent on three basic characteristics of a geologic CO2 storage site: (1) the potential for primary containment by the target formation; (2) the potential for secondary containment if the primary formation leaks; and (3) the potential for attenuation and dispersion of leaking CO2 if the primary formation leaks and secondary containment fails. The framework is implemented in a spreadsheet in which users enter numerical scores representing expert opinions or general information available from published materials along with estimates of uncertainty to evaluate the three basic characteristics in order to screen and rank candidate sites. Application of the framework to the Rio Visa Gas Field, Ventura Oil Field, and Mammoth Mountain demonstrates the approach. Refinements and extensions are possible through the use of more detailed data or model results in place of property proxies. Revisions and extensions to improve the approach are anticipated in the near future as it is used and tested by colleagues and collaborators.

  10. CO2 Flux Estimation Errors Associated with Moist Atmospheric Processes (United States)

    Parazoo, N. C.; Denning, A. S.; Kawa, S. R.; Pawson, S.; Lokupitiya, R.


    Vertical transport by moist sub-grid scale processes such as deep convection is a well-known source of uncertainty in CO2 source/sink inversion. However, a dynamical link between vertical transport, satellite based retrievals of column mole fractions of CO2, and source/sink inversion has not yet been established. By using the same offline transport model with meteorological fields from slightly different data assimilation systems, we examine sensitivity of frontal CO2 transport and retrieved fluxes to different parameterizations of sub-grid vertical transport. We find that frontal transport feeds off background vertical CO2 gradients, which are modulated by sub-grid vertical transport. The implication for source/sink estimation is two-fold. First, CO2 variations contained in moist poleward moving air masses are systematically different from variations in dry equatorward moving air. Moist poleward transport is hidden from orbital sensors on satellites, causing a sampling bias, which leads directly to small but systematic flux retrieval errors in northern mid-latitudes. Second, differences in the representation of moist sub-grid vertical transport in GEOS-4 and GEOS-5 meteorological fields cause differences in vertical gradients of CO2, which leads to systematic differences in moist poleward and dry equatorward CO2 transport and therefore the fraction of CO2 variations hidden in moist air from satellites. As a result, sampling biases are amplified and regional scale flux errors enhanced, most notably in Europe (0.43+/-0.35 PgC /yr). These results, cast from the perspective of moist frontal transport processes, support previous arguments that the vertical gradient of CO2 is a major source of uncertainty in source/sink inversion.

  11. Performance Analysis of Cold Energy Recovery from CO2 Injection in Ship-Based Carbon Capture and Storage (CCS

    Directory of Open Access Journals (Sweden)

    Hwalong You


    Full Text Available Carbon capture and storage (CCS technology is one of the practical solutions for mitigating the effects of global warming. When captured CO2 is injected into storage sites, the CO2 is subjected to a heating process. In a conventional CO2 injection system, CO2 cold energy is wasted during this heating process. This study proposes a new CO2 injection system that takes advantage of the cold energy using the Rankine cycle. The study compared the conventional system with the new CO2 injection system in terms of specific net power consumption, exergy efficiency, and life-cycle cost (LCC to estimate the economic effects. The results showed that the new system reduced specific net power consumption and yielded higher exergy efficiency. The LCC of the new system was more economical. Several cases were examined corresponding to different conditions, specifically, discharge pressure and seawater temperature. This information may affect decision-making when CCS projects are implemented.

  12. Geoelectric Monitoring of geological CO2 storage at Ketzin, Germany (CO2SINK project): Downhole and Surface-Downhole measurements (United States)

    Kiessling, D.; Schuett, H.; Schoebel, B.; Krueger, K.; Schmidt-Hattenberger, C.; Schilling, F.


    Numerical models of the CO2 storage experiment CO2SINK (CO2 Storage by Injection into a Natural Saline Aquifer at Ketzin), where CO2 is injected into a deep saline aquifer at roughly 650 m depth, yield a CO2 saturation of approximately 50% for large parts of the plume. Archie's equation predicts an increase of the resistivity by a factor of approximately 3 to 4 for the reservoir sandstone, and laboratory tests on Ketzin reservoir samples support this prediction. Modeling results show that tracking the CO2 plume may be doable with crosshole resistivity surveys under these conditions. One injection well and two observation wells were drilled in 2007 to a depth of about 800 m and were completed with "smart" casings, arranged L-shaped with distances of 50 m and 100 m. 45 permanent ring-shaped steel electrodes were attached to the electrically insulated casings of the three Ketzin wells at 590 m to 735 m depth with a spacing of about 10 m. It is to our knowledge the deepest permanent vertical electrical resistivity array (VERA) worldwide. The electrodes are connected to the current power supply and data registration units at the surface through custom-made cables. This deep electrode array allows for the registration of electrical resistivity tomography (ERT) data sets at basically any desired repetition rate and at very low cost, without interrupting the injection operations. The installation of all 45 electrodes succeeded. The electrodes are connected to the electrical cable, and the insulated casing stood undamaged. Even after 2-odd years under underground conditions only 6 electrodes are in a critical state now, caused by corrosion effects. In the framework of the COSMOS project (CO2-Storage, Monitoring and Safety Technology), supported by the German "Geotechnologien" program, the geoelectric monitoring has been performed. The 3D crosshole time-laps measurements are taken using dipole-dipole configurations. The data was inverted using AGI EarthImager 3D to obtain 3D

  13. Experimental Investigation on CO2 Methanation Process for Solar Energy Storage Compared to CO2-Based Methanol Synthesis

    NARCIS (Netherlands)

    Castellani, Beatrice; Gambelli, Alberto Maria; Morini, Elena; Nastasi, B.; Presciutti, Andrea; Filipponi, Mirko; Nicolini, Andrea; Rossi, Federico


    The utilization of the captured CO2 as a carbon source for the production of energy storage media offers a technological solution for overcoming crucial issues in current energy systems. Solar energy production generally does not match with energy demand because of its intermittent and

  14. CO2 capture by biomimetic adsorption: enzyme mediated co2 absorption for post-combustion carbon sequestration and storage process

    NARCIS (Netherlands)

    Russo, M.E.; Olivieri, G.; Salatino, P.; Marzocchella, A.


    The huge emission of greenhouse gases from fossil-fuelled power plants is emphasizing the need for efficient Carbon Capture and Storage (CCS) technologies. The biomimetic CO2 absorption in aqueous solutions has been recently investigated as a promising innovative alternative for post-combustion CCS.

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

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


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

  16. The potential of geological storage of CO2 in Austria: a techno-economic assessment (United States)

    Brüstle, Anna Katharina; Welkenhuysen, Kris; Bottig, Magdalena; Piessens, Kris; Ramirez, Andrea; Swenner, Rudy


    An impressive two-third or about 40GWh/y of electricity in Austria is produced from renewable energy sources, in particular hydro energy. For the remaining part the country depends on fossil fuels, which together with iron & steel production form the most CO2 intensive industries in Austria with a combined emission of just over 20Mt/y. According to the IEA, CO2 capture and geological storage (CCS) can reduce the global CO2 emission until 2050 by 17%. A correct assessment of CCS needs to start with the storage potential. Prior to this study, only general estimates of the theoretical capacity of Austrian reservoirs were available, thus, up until now, the realistic potential for CCS technology has not been assessed. Both for policy and industry, an assessment of the matched capacity is required, which is the capacity that actually will be used in CCS projects. This hurdle can be taken by applying a recently developed methodology (Welkenhuysen et al., 2013). This policy support system (PSS) consists of two parts, PSS Explorer and PSS III simulator. In brief, the methodology is based on expert judgements of potential reservoirs. These assessments can provide the best available data, including the expert's experience and possibly confidential data, without disclosing specific data. The geo-techno-economic calculation scheme PSS Explorer uses the expert input to calculate for each individual reservoir an assessment of the practical capacity (as probability density functions), in function of an acceptable price for storage. This practical capacity can then be used by the techno-economic PSS III simulator to perform advanced source-sink matching until 2050 and thus provide the matched reservoir capacity. The analysed reservoirs are 7 active or abandoned oil and gas reservoirs in Austria. The simulation of the electricity and iron & steel sector of Austria resulted in the estimation of the geological storage potential, taking into account geological, technological and

  17. The Baltic Basin: structure, properties of reservoir rocks, and capacity for geological storage of CO2

    Directory of Open Access Journals (Sweden)

    Vaher, Rein


    Full Text Available Baltic countries are located in the limits of the Baltic sedimentary basin, a 700 km long and 500 km wide synclinal structure. The axis of the syneclise plunges to the southwest. In Poland the Precambrian basement occurs at a depth of 5 km. The Baltic Basin includes the Neoproterozoic Ediacaran (Vendian at the base and all Phanerozoic systems. Two aquifers, the lower Devonian and Cambrian reservoirs, meet the basic requirements for CO2 storage. The porosity and permeability of sandstone decrease with depth. The average porosity of Cambrian sandstone at depths of 80–800, 800–1800, and 1800–2300 m is 18.6, 14.2, and 5.5%, respectively. The average permeability is, respectively, 311, 251, and 12 mD. Devonian sandstone has an average porosity of 26% and permeability in the range of 0.5–2 D. Prospective Cambrian structural traps occur only in Latvia. The 16 largest ones have CO2 storage capacity in the range of 2–74 Mt, with total capacity exceeding 400 Mt. The structural trapping is not an option for Lithuania as the uplifts there are too small. Another option is utilization of CO2 for enhanced oil recovery (EOR. The estimated total EOR net volume of CO2 (part of CO2 remaining in the formation in Lithuania is 5.6 Mt. Solubility and mineral trapping are a long-term option. The calculated total solubility trapping capacity of the Cambrian reservoir is as high as 11 Gt of CO2 within the area of the supercritical state of carbon dioxide.

  18. Using noble gas tracers to estimate residual CO2 saturation in the field: results from the CO2CRC Otway residual saturation and dissolution test (United States)

    LaForce, T.; Ennis-King, J.; Paterson, L.


    Residual CO2 saturation is a critically important parameter in CO2 storage as it can have a large impact on the available secure storage volume and post-injection CO2 migration. A suite of single-well tests to measure residual trapping was conducted at the Otway test site in Victoria, Australia during 2011. One or more of these tests could be conducted at a prospective CO2 storage site before large-scale injection. The test involved injection of 150 tonnes of pure carbon dioxide followed by 454 tonnes of CO2-saturated formation water to drive the carbon dioxide to residual saturation. This work presents a brief overview of the full test sequence, followed by the analysis and interpretation of the tests using noble gas tracers. Prior to CO2 injection krypton (Kr) and xenon (Xe) tracers were injected and back-produced to characterise the aquifer under single-phase conditions. After CO2 had been driven to residual the two tracers were injected and produced again. The noble gases act as non-partitioning aqueous-phase tracers in the undisturbed aquifer and as partitioning tracers in the presence of residual CO2. To estimate residual saturation from the tracer test data a one-dimensional radial model of the near-well region is used. In the model there are only two independent parameters: the apparent dispersivity of each tracer and the residual CO2 saturation. Independent analysis of the Kr and Xe tracer production curves gives the same estimate of residual saturation to within the accuracy of the method. Furthermore the residual from the noble gas tracer tests is consistent with other measurements in the sequence of tests.

  19. Assessment of CO2 storage performance of the Enhanced Coalbed Methane pilot site in Kaniow

    NARCIS (Netherlands)

    Bergen, F. van; Winthaegen, P.; Pagnier, H.; Krzystolik, P.; Jura, B.; Skiba, J.; Wageningen, N. van


    A pilot site for CO2 storage in coal seams was set-up in Poland, as has been reported on previous GHGT conferences. This site consisted of one injection and one production well. About 760 ton of CO2 has been injected into the reservoir from August 2004 to June 2005. Breakthrough of the injected CO2

  20. Numerical investigation of CO2 storage in hydrocarbon field using a geomechanical-fluid coupling model

    Directory of Open Access Journals (Sweden)

    Guang Li


    Full Text Available Increasing pore pressure due to CO2 injection can lead to stress and strain changes of the reservoir. One of the safely standards for long term CO2 storage is whether stress and strain changes caused by CO2 injection will lead to irreversible mechanical damages of the reservoir and impact the integrity of caprock which could lead to CO2 leakage through previously sealing structures. Leakage from storage will compromise both the storage capacity and the perceived security of the project, therefore, a successful CO2 storage project requires large volumes of CO2 to be injected into storage site in a reliable and secure manner. Yougou hydrocarbon field located in Orods basin was chosen as storage site based on it's stable geological structure and low leakage risks. In this paper, we present a fluid pressure and stress-strain variations analysis for CO2 geological storage based on a geomechanical-fluid coupling model. Using nonlinear elasticity theory to describe the geomechanical part of the model, while using the Darcy's law to describe the fluid flow. Two parts are coupled together using the poroelasticity theory. The objectives of our work were: 1 evaluation of the geomechanical response of the reservoir to different CO2 injection scenarios. 2 assessment of the potential leakage risk of the reservoir caused by CO2 injection.

  1. Rigorous Screening Technology for Identifying Suitable CO2 Storage Sites II

    Energy Technology Data Exchange (ETDEWEB)

    George J. Koperna Jr.; Vello A. Kuuskraa; David E. Riestenberg; Aiysha Sultana; Tyler Van Leeuwen


    This report serves as the final technical report and users manual for the 'Rigorous Screening Technology for Identifying Suitable CO2 Storage Sites II SBIR project. Advanced Resources International has developed a screening tool by which users can technically screen, assess the storage capacity and quantify the costs of CO2 storage in four types of CO2 storage reservoirs. These include CO2-enhanced oil recovery reservoirs, depleted oil and gas fields (non-enhanced oil recovery candidates), deep coal seems that are amenable to CO2-enhanced methane recovery, and saline reservoirs. The screening function assessed whether the reservoir could likely serve as a safe, long-term CO2 storage reservoir. The storage capacity assessment uses rigorous reservoir simulation models to determine the timing, ultimate storage capacity, and potential for enhanced hydrocarbon recovery. Finally, the economic assessment function determines both the field-level and pipeline (transportation) costs for CO2 sequestration in a given reservoir. The screening tool has been peer reviewed at an Electrical Power Research Institute (EPRI) technical meeting in March 2009. A number of useful observations and recommendations emerged from the Workshop on the costs of CO2 transport and storage that could be readily incorporated into a commercial version of the Screening Tool in a Phase III SBIR.

  2. Simulated anthropogenic CO2 storage and acidification of the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    J. Palmiéri


    Full Text Available Constraints on the Mediterranean Sea's storage of anthropogenic CO2 are limited, coming only from data-based approaches that disagree by more than a factor of two. Here we simulate this marginal sea's anthropogenic carbon storage by applying a perturbation approach in a high-resolution regional model. Our model simulates that, between 1800 and 2001, basin-wide CO2 storage by the Mediterranean Sea has increased by 1.0 Pg C, a lower limit based on the model's weak deep-water ventilation, as revealed by evaluation with CFC-12. Furthermore, by testing a data-based approach (transit time distribution in our model, comparing simulated anthropogenic CO2 to values computed from simulated CFC-12 and physical variables, we conclude that the associated basin-wide storage of 1.7 Pg, published previously, must be an upper bound. Out of the total simulated storage of 1.0 Pg C, 75% comes from the air–sea flux into the Mediterranean Sea and 25% comes from net transport from the Atlantic across the Strait of Gibraltar. Sensitivity tests indicate that the Mediterranean Sea's higher total alkalinity, relative to the global-ocean mean, enhances the Mediterranean's total inventory of anthropogenic carbon by 10%. Yet the corresponding average anthropogenic change in surface pH does not differ significantly from the global-ocean average, despite higher total alkalinity. In Mediterranean deep waters, the pH change is estimated to be between −0.005 and −0.06 pH units.

  3. Large divergence of satellite and Earth system model estimates of global terrestrial CO2 fertilization (United States)

    Smith, W. Kolby; Reed, Sasha C.; Cleveland, Cory C.; Ballantyne, Ashley P; Anderegg, William R. L.; Wieder, William R.; Liu, Yi Y; Running, Steven W.


    Atmospheric mass balance analyses suggest that terrestrial carbon (C) storage is increasing, partially abating the atmospheric [CO2] growth rate, although the continued strength of this important ecosystem service remains uncertain. Some evidence suggests that these increases will persist owing to positive responses of vegetation growth (net primary productivity; NPP) to rising atmospheric [CO2] (that is, ‘CO2 fertilization’). Here, we present a new satellite-derived global terrestrial NPP data set, which shows a significant increase in NPP from 1982 to 2011. However, comparison against Earth system model (ESM) NPP estimates reveals a significant divergence, with satellite-derived increases (2.8 ± 1.50%) less than half of ESM-derived increases (7.6  ±  1.67%) over the 30-year period. By isolating the CO2 fertilization effect in each NPP time series and comparing it against a synthesis of available free-air CO2 enrichment data, we provide evidence that much of the discrepancy may be due to an over-sensitivity of ESMs to atmospheric [CO2], potentially reflecting an under-representation of climatic feedbacks and/or a lack of representation of nutrient constraints. Our understanding of CO2 fertilization effects on NPP needs rapid improvement to enable more accurate projections of future C cycle–climate feedbacks; we contend that better integration of modelling, satellite and experimental approaches offers a promising way forward.

  4. Economic Operation of Supercritical CO2 Refrigeration Energy Storage Technology (United States)

    Hay, Ryan

    With increasing penetration of intermittent renewable energy resources, improved methods of energy storage are becoming a crucial stepping stone in the path toward a smarter, greener grid. SuperCritical Technologies is a company based in Bremerton, WA that is developing a storage technology that can operate entirely on waste heat, a resource that is otherwise dispelled into the environment. The following research models this storage technology in several electricity spot markets around the US to determine if it is economically viable. A modification to the storage dispatch scheme is then presented which allows the storage unit to increase its profit in real-time markets by taking advantage of extreme price fluctuations. Next, the technology is modeled in combination with an industrial load profile on two different utility rate schedules to determine potential cost savings. The forecast of facility load has a significant impact on savings from the storage dispatch, so an exploration into this relationship is then presented.

  5. Does CO2 enhance short-term storage success of Chinook salmon (Oncorhynchus tshawytscha) milt? (United States)

    Bencic, D C; Ingermann, R L; Cloud, J G


    Successful short-term storage of salmonid milt depends on numerous factors, including temperature, fluid volume, and gaseous environment, with storage at low temperatures under an atmosphere of 100% O2 being the most common method. Salmonid sperm maintained in a storage environment with elevated carbon dioxide (CO2) levels, such as the approximately 4% CO2 in exhaled air, are not motile when activated. While these modest levels of CO2 inhibit sperm motility, the effect is reversible within hours after exposure to a CO2-free oxygenated environment. Therefore, the effect of CO2 (as a component gas in the storage environment) on chinook salmon (Oncorhynchus tshawytscha) sperm motility and viability was examined. The hypothesis of the current investigation was that CO2-exposure with subsequent CO2 removal would be beneficial during short-term chinook salmon milt storage. Milt samples were collected from mature (adult) and precocious (jack) male chinook salmon and stored under various CO2 and O2 levels at 3 to 4 degrees C for up to 14 days. Milt samples were then removed from the incubation environments and maintained under CO2-free humidified air with continuous mixing for 4 h at 10 degrees C before analysis of motility. The resultant motility of samples incubated under 3.5% or less CO2 was not different than controls during the 14 d incubation period; motility of samples stored under higher CO2 tensions were significantly lower. The motility of samples incubated under 3.5% CO2 reached the maximum recovered motility after 2 h exposure to CO2-free humidified air, while the motility of sperm incubated under 13.4% CO2 levels recovered no motility even after 6 h exposure to CO2-free humidified air. The motility of samples incubated under normoxia was significantly greater than that of samples incubated under hyperoxia (approximately 90% O2) at both 7 and 14 d, regardless of the CO2 level. Sperm viability was relatively unaltered by any of the incubation conditions examined

  6. 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


    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.


    Energy Technology Data Exchange (ETDEWEB)

    Bert Bock; Richard Rhudy; Howard Herzog; Michael Klett; John Davison; Danial G. De La Torre Ugarte; Dale Simbeck


    This project developed life-cycle costs for the major technologies and practices under development for CO{sub 2} storage and sink enhancement. The technologies evaluated included options for storing captured CO{sub 2} in active oil reservoirs, depleted oil and gas reservoirs, deep aquifers, coal beds, and oceans, as well as the enhancement of carbon sequestration in forests and croplands. The capture costs for a nominal 500 MW{sub e} integrated gasification combined cycle plant from an earlier study were combined with the storage costs from this study to allow comparison among capture and storage approaches as well as sink enhancements.

  8. Influence of shale-total organic content on CO2 geo-storage potential (United States)

    Arif, Muhammad; Lebedev, Maxim; Barifcani, Ahmed; Iglauer, Stefan


    Shale CO2 wettability is a key factor which determines the structural trapping capacity of a caprock. However, the influence of shale-total organic content (TOC) on wettability (and thus on storage potential) has not been evaluated despite the fact that naturally occurring shale formations can vary dramatically in TOC, and that even minute TOC strongly affects storage capacities and containment security. Thus, there is a serious lack of understanding in terms of how shale, with varying organic content, performs in a CO2 geo-storage context. We demonstrate here that CO2-wettability scales with shale-TOC at storage conditions, and we propose that if TOC is low, shale is suitable as a caprock in conventional structural trapping scenarios, while if TOC is ultrahigh to medium, the shale itself is suitable as a storage medium (via adsorption trapping after CO2 injection through fractured horizontal wells).

  9. Improving soil CO2 efflux estimates from in-situ soil CO2 sensors with gas transport measurements (United States)

    Sanchez-Canete, E. P.; Barron-Gafford, G.; Van Haren, J. L. M.; Scott, R. L.


    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

  10. On CO2 Behavior in the Subsurface, Following Leakage from aGeologic Storage Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, Karsten


    The amounts of CO2 that would need to be injected intogeologic storage reservoirs to achieve a significant reduction ofatmospheric emissions are very large. A 1000 MWe coal-fired power plantemits approximately 30,000 tonnes of CO2 per day, 10 Mt per year(Hitchon, 1996). When injected underground over a typical lifetime of 30years of such a plant, the CO2 plume may occupy a large area of order 100km2 or more, and fluid pressure increase in excess of 1 bar(corresponding to 10 m water head) may extend over an area of more than2,500 km2 (Pruess, et al., 2003). The large areal extent expected for CO2plumes makes it likely that caprock imperfections will be encountered,such as fault zones or fractures, which may allow some CO2 to escape fromthe primary storage reservoir. Under most subsurface conditions oftemperature and pressure, CO2 is buoyant relative to groundwaters. If(sub-)vertical pathways are available, CO2 will tend to flow upward and,depending on geologic conditions, may eventually reach potablegroundwater aquifers or even the land surface. Leakage of CO2 could alsooccur along wellbores, including pre-existing and improperly abandonedwells, or wells drilled in connection with the CO2 storage operations.The pressure increases accompanying CO2 injection will give rise tochanges in effective stress that could cause movement along faults,increasing permeability and potential for leakage.Escape of CO2 from aprimary geologic storage reservoir and potential hazards associated withits discharge at the land surface raise a number of concerns, including(1) acidification of groundwater resources, (2) asphyxiation hazard whenleaking CO2 is discharged at the land surface, (3) increase inatmospheric concentrations of CO2, and (4) damage from a high-energy,eruptive discharge (if such discharge is physically possible). In orderto gain public acceptance for geologic storage as a viable technology forreducing atmospheric emissions of CO2, it is necessary to address theseissues

  11. Leakage of CO2 from geologic storage: Role of secondaryaccumulation at shallow depth

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, K.


    Geologic storage of CO2 can be a viable technology forreducing atmospheric emissions of greenhouse gases only if it can bedemonstrated that leakage from proposed storage reservoirs and associatedhazards are small or can be mitigated. Risk assessment must evaluatepotential leakage scenarios and develop a rational, mechanisticunderstanding of CO2 behavior during leakage. Flow of CO2 may be subjectto positive feedbacks that could amplify leakage risks and hazards,placing a premium on identifying and avoiding adverse conditions andmechanisms. A scenario that is unfavorable in terms of leakage behavioris formation of a secondary CO2 accumulation at shallow depth. This paperdevelops a detailed numerical simulation model to investigate CO2discharge from a secondary accumulation, and evaluates the role ofdifferent thermodynamic and hydrogeologic conditions. Our simulationsdemonstrate self-enhancing as well as self-limiting feedbacks.Condensation of gaseous CO2, 3-phase flow of aqueous phase -- liquid CO2-- gaseous CO2, and cooling from Joule-Thomson expansion and boiling ofliquid CO2 are found to play important roles in the behavior of a CO2leakage system. We find no evidence that a subsurface accumulation of CO2at ambient temperatures could give rise to a high-energy discharge, aso-called "pneumatic eruption."

  12. Numerical simulation of CO2 geological storage in saline aquifers – case study of Utsira formation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zheming; Agarwal, Ramesh K. [Department of Mechanical Engineering and Materials Science, Washington University, St. Louis, MO 63130 (United States)


    CO2 geological storage (CGS) is one of the most promising technologies to address the issue of excessive anthropogenic CO2 emissions in the atmosphere due to fossil fuel combustion for electricity generation. In order to fully exploit the storage potential, numerical simulations can help in determining injection strategies before the deployment of full scale sequestration in saline aquifers. This paper presents the numerical simulations of CO2 geological storage in Utsira saline formation where the sequestration is currently underway. The effects of various hydrogeological and numerical factors on the CO2 distribution in the topmost hydrogeological layer of Utsira are discussed. The existence of multiple pathways for upward mobility of CO2 into the topmost layer of Utsira as well as the performance of the top seal are also investigated.

  13. Harvesting Duke FACE: improving estimates of productivity and biomass under elevated CO2 (United States)

    McCarthy, H. R.; Oren, R.; Kim, D.; Tor-ngern, P.; Johnsen, K. H.; Maier, C. A.


    Free air CO2 enrichment experiments (FACE) have greatly advanced our knowledge on the impacts of increasing atmospheric CO2 concentrations in developing and mature ecosystems. These experiments have provided years of data on changes in physiology and ecosystem functions, such as photosynthesis, water use, net primary productivity (NPP), ecosystem carbon storage, and nutrient cycling. As these experiments come to a close, there has also been the opportunity to add critically lacking biometric data, which can be obtained only through destructive measurements. After 15 years of CO2 elevation at the Duke Forest FACE, a 28 year old pine plantation with a hardwood understory, a vast array of biometric data was obtained through harvesting of >1150 trees in both elevated and ambient CO2 plots. Harvested trees included pines and hardwoods, understory and overstory trees. The harvest provided direct assessments of leaf, stem and branch biomass, as well as the vertical distribution of these masses. In combination with leaf and wood level properties (e.g. specific leaf area, wood density), it was possible to explore potential CO2 effects on allometric relationships between plant parts, and stem and canopy shape and distribution. Although stimulatory effects of elevated CO2 on NPP are well established in this forest (averaging 27%), harvest results thus far indicate few changes in basic allometric relationships, such as height-diameter relationships, proportion of mass contained in different plant parts (stems vs. leaves vs. branches), distribution of leaves within the canopy and stem shape. The coupling of site-specific biometric relationships with long-term data on tree growth and mortality will reduce current sources of uncertainty in estimates of NPP and carbon storage under future increased CO2 conditions. Recent efforts in data-model synthesis have demonstrated the critical need for such data as constraints and initial values in ecosystem and earth system models; these

  14. Geochemical modelling of worst-case leakage scenarios at potential CO2-storage sites - CO2 and saline water contamination of drinking water aquifers (United States)

    Szabó, Zsuzsanna; Edit Gál, Nóra; Kun, Éva; Szőcs, Teodóra; Falus, György


    Carbon Capture and Storage is a transitional technology to reduce greenhouse gas emissions and to mitigate climate change. Following the implementation and enforcement of the 2009/31/EC Directive in the Hungarian legislation, the Geological and Geophysical Institute of Hungary is required to evaluate the potential CO2 geological storage structures of the country. Basic assessment of these saline water formations has been already performed and the present goal is to extend the studies to the whole of the storage complex and consider the protection of fresh water aquifers of the neighbouring area even in unlikely scenarios when CO2 injection has a much more regional effect than planned. In this work, worst-case scenarios are modelled to understand the effects of CO2 or saline water leaks into drinking water aquifers. The dissolution of CO2 may significantly change the pH of fresh water which induces mineral dissolution and precipitation in the aquifer and therefore, changes in solution composition and even rock porosity. Mobilization of heavy metals may also be of concern. Brine migration from CO2 reservoir and replacement of fresh water in the shallower aquifer may happen due to pressure increase as a consequence of CO2 injection. The saline water causes changes in solution composition which may also induce mineral reactions. The modelling of the above scenarios has happened at several methodological levels such as equilibrium batch, kinetic batch and kinetic reactive transport simulations. All of these have been performed by PHREEQC using the PHREEQC.DAT thermodynamic database. Kinetic models use equations and kinetic rate parameters from the USGS report of Palandri and Kharaka (2004). Reactive transport modelling also considers estimated fluid flow and dispersivity of the studied formation. Further input parameters are the rock and the original ground water compositions of the aquifers and a range of gas-phase CO2 or brine replacement ratios. Worst-case scenarios

  15. Numerical modeling of CO2 mineralisation during storage in deep saline aquifers

    NARCIS (Netherlands)

    Ranganathan, P.; Van Hemert, P.; Rudolph, S.J.; Zitha, P.L.J.


    Simulations are performed to evaluate the feasibility of a potential site within the Rotliegend sandstone formation in the Dutch subsurface at a depth of around 3000 m for CO2 sequestration using the numerical simulator CMG-GEM. Three CO2 storage trapping mechanisms are studied: (1) mobility

  16. Second Generation CO2 FEP Analysis: CASSIF - Carbon Storage Scenario Identification Framework

    NARCIS (Netherlands)

    Yavuz, F.; Tilburg, T. van; David, P.; Spruijt, M.; Wildenborg, T.


    Carbon dioxide Capture and Storage (CCS) is a promising contribution to reduce further increase of atmospheric CO2 emissions from fossil fuels. The CCS concept anticipates that large amounts of CO2 are going to be stored in the subsurface for the long term. Since CCS is a rather new technology,

  17. GHGT-10 : Assessing the integrity of fault- and top seals at CO2 storage sites

    NARCIS (Netherlands)

    Orlic, B.; Heege J.H. ter; Wassing, B.


    Induced stress changes due to CO2 injection into geological reservoirs can mechanically damage bounding fault- and top seals creating preferential pathways for CO2 migration from the containment or trigger existing faults causing seismic activity at storage sites. In this paper we present

  18. CO2 Storage Potential of the Eocene Tay Sandstone, Central North Sea, UK (United States)

    Gent, Christopher; Williams, John


    Carbon Capture and Storage (CCS) is crucial for low-carbon industry, climate mitigation and a sustainable energy future. The offshore capacity of the UK is substantial and has been estimated at 78 Gt of CO2 in saline aquifers and hydrocarbon fields. The early-mid Eocene Tay Sandstone Member of the Central North Sea (CNS) is a submarine-fan system and potential storage reservoir with a theoretical capacity of 123 Mt of CO2. The Tay Sandstone comprises of 4 sequences, amalgamating into a fan complex 125km long and 40 km at a minimum of 1500 m depth striking NW-SE, hosting several hydrocarbon fields including Gannett A, B, D and Pict. In order to better understand the storage potential and characteristics, the Tay Sandstone over Quadrant 21 has been interpreted using log correlation and 3D seismic. Understanding the internal and external geometry of the sandstone as well as the lateral extent of the unit is essential when considering CO2 vertical and horizontal fluid flow pathways and storage security. 3D seismic mapping of a clear mounded feature has revealed the youngest sequence of the Tay complex; a homogenous sand-rich channel 12 km long, 1.5 km wide and on average 100 m thick. The sandstone has porosity >35%, permeability >5 D and a net to gross of 0.8, giving a total pore volume of 927x106 m3. The remaining three sequences are a series of stacked channels and interbedded mudstones which are more quiescent on the seismic, however, well logs indicate each subsequent sequence reduce in net to gross with age as mud has a greater influence in the early fan system. Nevertheless, the sandstone properties remain relatively consistent and are far more laterally extensive than the youngest sequence. The Tay Sandstone spatially overlaps several other potential storage sites including the older Tertiary sandstones of the Cromarty, Forties and Mey Members and deeper Jurassic reservoirs. This favours the Tay Sandstone to be considered in a secondary or multiple stacked

  19. A simple empirical model estimating atmospheric CO2 background concentrations (United States)

    Reuter, M.; Buchwitz, M.; Schneising, O.; Heymann, J.; Guerlet, S.; Cogan, A. J.; Bovensmann, H.; Burrows, J. P.


    A simple empirical CO2 model (SECM) is presented to estimate column-average dry-air mole fractions of atmospheric CO2 (XCO2) as well as mixing ratio profiles. SECM is based on a simple equation depending on 17 empirical parameters, latitude, and date. The empirical parameters have been determined by least squares fitting to NOAA's (National Oceanic and Atmospheric Administration) assimilation system CarbonTracker version 2010 (CT2010). Comparisons with TCCON (total column carbon observing network) FTS (Fourier transform spectrometer) measurements show that SECM XCO2 agrees quite well with reality. The synthetic XCO2 values have a standard error of 1.39 ppm and systematic station-to-station biases of 0.46 ppm. Typical column averaging kernels of the TCCON FTS, a SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric CHartographY), and two GOSAT (Greenhouse gases Observing SATellite) XCO2 retrieval algorithms have been used to assess the smoothing error introduced by using SECM profiles instead of CT2010 profiles as a priori. The additional smoothing error amounts to 0.17 ppm for a typical SCIAMACHY averaging kernel and is most times much smaller for the other instruments (e.g. 0.05 ppm for a typical TCCON FTS averaging kernel). Therefore, SECM is well-suited to provide a priori information for state of the art ground-based (FTS) and satellite-based (GOSAT, SCIAMACHY) XCO2 retrievals. Other potential applications are: (i) quick check for obvious retrieval errors (by monitoring the difference to SECM), (ii) near real time processing systems (that cannot make use of models like CT2010 operated in delayed mode), (iii) "CO2 proxy" methods for XCH4 retrievals (as correction for the XCO2 background), (iv) observing system simulation experiments especially for future satellite missions.

  20. CO2 Leakage, Storage and Injection Monitoring by Using Experimental, Numerical and Analytical Methods

    Directory of Open Access Journals (Sweden)

    A. Namdar


    Full Text Available The maintaining environment is priority to any plan in human life. It is planned for monitoring CO2 injection, storage and leakage by using geophysical, numerical and analytical methods in seismic zone. In this regard the mineralogy, chemical composite, lithology, seismic wave propagation, small earthquake, accelerating natural earthquake, thermal stress-strain modeling, ground movement level and fault activation will be consider. It is expected to better understand CO2 leakage, storage and injection process and problems.

  1. Status of Geological Storage of CO2 as Part of Negative Emissions Strategy (United States)

    Benson, S. M.


    Recent analyses show that many GHG stabilization scenarios require technologies that permanently extract CO2 from the atmosphere -so-called "net negative emissions." Among the most promising negative emissions approaches is bioenergy with carbon capture and storage (BECCS). The most mature options for CO2 storage are in sedimentary rocks located in thick sedimentary basins. Within those basins, CO2 can be stored either in depleted or depleting hydrocarbon formations or in so-called saline aquifers. In addition to the economic costs of bioenergy with CO2 capture, key to the success of and scale at which BECCS can contribute to negative emissions is the ability to store quantities on the order of 1 Gt per year of CO2. Today, about 65 Mt of CO2 per year are injected underground for the purposes of enhancing oil recovery (CO2-EOR) or for CO2 storage, the vast majority being for CO2-EOR. Achieving 1 Gt per year of negative emissions will require a 15-fold scale up of the current injection operations. This paper will review the conditions necessary for storage at this scale, identify what has been learned from nearly 2 decades of experience with CO2 storage that provides insight into the feasibility of CO2 storage on this scale, and identify critical issues that remain to be resolved to meet these ambitious negative emissions targets. Critical technological issues include but are not limited to: the amount of CO2 storage capacity that is available and where it is located in relation to biomass energy resources; identification of sustainable injection rates and how this depends on the properties of the geological formation; the extent to which water extraction will be required to manage the magnitude of pressure buildup; identification of regions at high risk for induced seismicity that could damage structures and infrastructure; and selection of sites with a adequate seals to permanently contain CO2. Social, economic and political issues are also important: including the

  2. European and global perspectives for CO2 capture and storage

    Energy Technology Data Exchange (ETDEWEB)

    Groenenberg, H.; Uyterlinde, M. [ECN Policy Studies (Netherlands)


    CO{sub 2} capture and storage (CCS) is increasingly mentioned as one of the options in the portfolio to mitigate climate change. CCS involves the capture of CO{sub 2} from a large point source, compression, transport and subsequent storage in a geological reservoir, the ocean, or in mineral carbonates. This paper will provide results of the scenarios analysed using 10 advanced energy models. Two policy approaches are compared in order to address the question how to achieve significant CO{sub 2} emission reductions through the application of CCS technologies. The analysis shows that CCS can provide an important contribution to mitigating climate change. Up to 30% of global CO{sub 2} emissions could be captured in 2050, while for Europe, due to a more limited growth of the power sector than in some other world regions, this would amount to some 22% of total CO{sub 2} emissions. The CCS policies not only induce the large-scale introduction of CCS systems in the electricity sector, but they also accelerate the penetration of renewable energy sources and nuclear. Policies that provide flexibility, for instance through emission trading, are more cost-effective than those obliging CCS to be installed with all new fossil power plants. Therefore, it is recommended to employ mixes of the different CO{sub 2} emission reduction options available, also depending on regional circumstances. The uncertainties, particularly in storage capacities, are large. Being a new technology, the actual deployment of CCS will also depend on public perception and on how legal and regulatory aspects related to risks and liabilities are addressed. (au)

  3. Effects of CO2 gas as leaks from geological storage sites on agro-ecosystems

    DEFF Research Database (Denmark)

    Patil, Ravi; Colls, Jeremy J; Steven, Michael D


    Carbon capture and storage in geological formations has potential risks in the long-term safety because of the possibility of CO2 leakage. Effects of leaking gas, therefore, on vegetation, soil, and soil-inhabiting organisms are critical to understand. An artificial soil gassing and response...... to control plot. A negative correlation (r = -0.95) between soil CO2 and O2 concentrations indicated that injected CO2 displaced O2 from soil. Gassing CO2 reduced soil pH both in grass and fallow plots (p = 0.012). The number of earthworm castings was twice as much in gassed plots than in control plots....... This study showed adverse effects of CO2 gas on agro-ecosystem in case of leakage from storage sites to surface....

  4. Regional CO2 flux estimates for 2009-2010 based on GOSAT and ground-based CO2 observations (United States)

    Maksyutov, S.; Takagi, H.; Valsala, V. K.; Saito, M.; Oda, T.; Saeki, T.; Belikov, D. A.; Saito, R.; Ito, A.; Yoshida, Y.; Morino, I.; Uchino, O.; Andres, R. J.; Yokota, T.


    We present the application of a global carbon cycle modeling system to the estimation of monthly regional CO2 fluxes from the column-averaged mole fractions of CO2 (XCO2) retrieved from spectral observations made by the Greenhouse gases Observing SATellite (GOSAT). The regional flux estimates are to be publicly disseminated as the GOSAT Level 4 data product. The forward modeling components of the system include an atmospheric tracer transport model, an anthropogenic emissions inventory, a terrestrial biosphere exchange model, and an oceanic flux model. The atmospheric tracer transport was simulated using isentropic coordinates in the stratosphere and was tuned to reproduce the age of air. We used a fossil fuel emission inventory based on large point source data and observations of nighttime lights. The terrestrial biospheric model was optimized by fitting model parameters to observed atmospheric CO2 seasonal cycle, net primary production data, and a biomass distribution map. The oceanic surface pCO2 distribution was estimated with a 4-D variational data assimilation system based on reanalyzed ocean currents. Monthly CO2 fluxes of 64 sub-continental regions, between June 2009 and May 2010, were estimated from GOSAT FTS SWIR Level 2 XCO2 retrievals (ver. 02.00) gridded to 5° × 5° cells and averaged on a monthly basis and monthly-mean GLOBALVIEW-CO2 data. Our result indicated that adding the GOSAT XCO2 retrievals to the GLOBALVIEW data in the flux estimation brings changes to fluxes of tropics and other remote regions where the surface-based data are sparse. The uncertainties of these remote fluxes were reduced by as much as 60% through such addition. Optimized fluxes estimated for many of these regions, were brought closer to the prior fluxes by the addition of the GOSAT retrievals. In most of the regions and seasons considered here, the estimated fluxes fell within the range of natural flux variabilities estimated with the component models.

  5. Regional CO2 flux estimates for 2009–2010 based on GOSAT and ground-based CO2 observations

    Directory of Open Access Journals (Sweden)

    S. Maksyutov


    Full Text Available We present the application of a global carbon cycle modeling system to the estimation of monthly regional CO2 fluxes from the column-averaged mole fractions of CO2 (XCO2 retrieved from spectral observations made by the Greenhouse gases Observing SATellite (GOSAT. The regional flux estimates are to be publicly disseminated as the GOSAT Level 4 data product. The forward modeling components of the system include an atmospheric tracer transport model, an anthropogenic emissions inventory, a terrestrial biosphere exchange model, and an oceanic flux model. The atmospheric tracer transport was simulated using isentropic coordinates in the stratosphere and was tuned to reproduce the age of air. We used a fossil fuel emission inventory based on large point source data and observations of nighttime lights. The terrestrial biospheric model was optimized by fitting model parameters to observed atmospheric CO2 seasonal cycle, net primary production data, and a biomass distribution map. The oceanic surface pCO2 distribution was estimated with a 4-D variational data assimilation system based on reanalyzed ocean currents. Monthly CO2 fluxes of 64 sub-continental regions, between June 2009 and May 2010, were estimated from GOSAT FTS SWIR Level 2 XCO2 retrievals (ver. 02.00 gridded to 5° × 5° cells and averaged on a monthly basis and monthly-mean GLOBALVIEW-CO2 data. Our result indicated that adding the GOSAT XCO2 retrievals to the GLOBALVIEW data in the flux estimation brings changes to fluxes of tropics and other remote regions where the surface-based data are sparse. The uncertainties of these remote fluxes were reduced by as much as 60% through such addition. Optimized fluxes estimated for many of these regions, were brought closer to the prior fluxes by the addition of the GOSAT retrievals. In most of the regions and seasons considered here, the estimated fluxes fell within the range of natural flux variabilities estimated with the component models.

  6. Developments since 2005 in understanding potential environmental impacts of CO2 leakage from geological storage

    NARCIS (Netherlands)

    Jones, D.G.; Beaubien, S.E.; Blackford, J.C.; Foekema, E.M.; Lions, J.; Vittor, de C.; West, J.M.; Widdicombe, S.; Hauton, C.; Queiros, A.M.


    This paper reviews research into the potential environmental impacts of leakage from geological storage of CO2 since the publication of the IPCC Special Report on Carbon Dioxide Capture and Storage in 2005. Possible impacts are considered on onshore (including drinking water aquifers) and offshore

  7. [Error analysis of CO2 storage flux in a temperate deciduous broadleaved forest based on different scalar variables]. (United States)

    Wang, Jing; Wang, Xing-chang; Wang, Chuan-kuan


    Using the measurement data from an 8-level vertical profile of CO2/H2 0 in a temperate deciduous broadleaved forest at the Maoershan Forest Ecosystem Research Station, Northeast China, this paper quantified the errors of CO2 storage flux (Fs ) calculated with three scalar variables, i. e. , CO2 density (rho c), molar fraction (cc), and molar mixing ratio relative to dry air (Xc). The dry air storage in the control volume of flux measurement was not a constant, and thus, the fluctuation of the dry air storage could cause the CO2 molecules transporting out of or into the control volume, i. e. , the variation of the dry air storage adjustment term (Fsd). During nighttime and day-night transition periods, the relative magnitude of Fsd to eddy flux was larger, and ignoring the Fsd could introduce errors in calculating the net CO2 exchange between the forest ecosystem and the atmosphere. Three error sources in the Fs calculation could be introduced from the atmospheric hydrothermal processes, i. e. , 1) air temperature fluctuation, which could cause the largest error, with one order of magnitude larger than that caused by atmospheric pressure (P) , 2) water vapor, its effect being larger than that of P in warm and moist summer but smaller in cold and dry winter, and 3) P, whose effect was generally smaller throughout the year. In estimating the effective CO2 storage (Fs_E) , the Fs value calculated with rho c, cc, and Xc was overestimated averagely by 8. 5%, suggested that in the calculation of Fs, adopting the Xc conservation to atmospheric hydrothermal processes could be more appropriate to minimize the potential errors.

  8. Recent advances in risk assessment and risk management of geologic CO2 storage


    Pawar, Rajesh J.; Bromhal, Grant S.; Carey, J. William; Foxall, William; Korre, Anna; Ringrose, Philip S.; Tucker, Owain; Watson, Maxwell N.; White, Joshua A.


    ? 2015 Elsevier Ltd.This paper gives an overview of the advances made in the field of risk assessment and risk management of geologic CO2 storage (GCS), since the publication of the IPCC Special Report on Carbon Capture and Storage in 2005. Development and operation of a wide range of demonstration projects coupled with development of new regulations for safe injection and storage of CO2 have led to development and deployment of a range of risk assessment approaches. New methods and tools hav...

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


    Pranoto, Arif


    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 ...

  10. Estimating global CO2 surface fluxes using CO2 and δ 13C data from the NOAA/CMDL network. (United States)

    Miller, J. B.; Denning, A. S.; Peters, W.; Bruhwiler, L.; Tans, P. P.


    In the last several years there has been considerable attention devoted to using global time-space patterns of CO2 in the atmosphere to infer surface fluxes. Here, we present flux results derived from both CO2 and δ 13C, using data from the NOAA/CMDL sampling network in a three-dimensional inversion framework. δ 13C data has been used previously but either in a two-dimensional transport framework, or using data from a small number of sampling sites. While it is clear that atmospheric δ 13C contains unique information about surface flux patterns, it remains unclear exactly where and when δ 13C is useful, given uncertainties in the 13C budget. We will use a Bayesian inversion setup in which CO2 and δ 13C data will be used to optimize not only surface fluxes but also patterns of isotopic fractionation and disequilibrium. Within this framework, we will be able to formally assess how much information δ 13C data add compared to CO2 alone, given uncertainties in CO2 data, δ 13C data, fractionation, disequilibrium, and first guesses of fluxes. This analysis will allow us to answer the question of what advances need to occur so that the atmospheric δ 13C signal can be used most effectively. Finally, using our best uncertainty estimates, we will compare surface fluxes derived from CO2 and δ 13C data.

  11. Salt concentrations during water production resulting from CO2 storage

    DEFF Research Database (Denmark)

    Walter, Lena; Class, Holger; Binning, Philip John


    present in the saline aquifer. The brine can be displaced over large areas and can reach shallower groundwater resources. High salt concentrations could lead to a degradation of groundwater quality. For water suppliers the most important information is whether and how much salt is produced at a water...... production well. In this approach the salt concentrations at water production wells depending on different parameters are determined for the assumption of a 2D model domain accounting for groundwater flow. Recognized ignorance resulting from grid resolution is qualitatively studied and statistical...... uncertainty is investigated for three parameters: the well distance, the water production rate, and the permeability of the aquifer. One possible way of estimating statistical uncertainties and providing probabilities is performing numerical Monte Carlo (MC) simulations. The MC approach is computationally...

  12. On the potential for CO2 mineral storage in continental flood basalts – PHREEQC batch- and 1D diffusion–reaction simulations


    Van Pham, Thi H; Aagaard, Per; Hellevang, Helge


    Abstract Continental flood basalts (CFB) are considered as potential CO2 storage sites because of their high reactivity and abundant divalent metal ions that can potentially trap carbon for geological timescales. Moreover, laterally extensive CFB are found in many place in the world within reasonable distances from major CO2 point emission sources. Based on the mineral and glass composition of the Columbia River Basalt (CRB) we estimated the potential of CFB to store CO2 in secondary carbonat...

  13. MERIS Ocean Colour Data for the Estimation of Surface Water pCO2: The Case Studies of Peru and Namibia

    DEFF Research Database (Denmark)

    Karagali, Ioanna; Badger, Merete; Sørensen, Lise Lotte


    Carbon dioxide fluxes between the ocean and atmosphere are important when trying to estimate the amount of existing atmospheric CO2. The ocean can potentially be considered as a storage or source of CO2 depending on temperature, salinity, biological activity and wind. To identify the role...... of a region, CO2 fluxes must be estimated. The air-sea exchange of CO2 depends on the partial pressures of atmospheric and oceanic CO2 and a wind related exchange coefficient. Direct in situ measurements are expensive, operationally demanding and of low spatial resolution. It has been shown that indirect...... estimation of oceanic pCO2 is possible due to its strong dependence on temperature. Primary production may also influence the CO2 concentration in the water, due to the consumption by phytoplankton. The present study aims at estimating the oceanic pCO2 with the use of satellite measurements for water...

  14. Impacts of deforestation and reforestation on soil organic carbon storage and CO2 emission

    Directory of Open Access Journals (Sweden)

    Mohammad Ghannadi


    Full Text Available Soil organic carbon (SOC storage and CO2 flux into the atmosphere can be influenced by land use change, especially re/deforestation. The impacts of conversion of primary deciduous (PF to secondary coniferous (SF forest and deforestation of PF land to abandoned rangeland (AR on various soil properties, SOC storage, and soil CO2 emission were investigated on the selected sites (Neshat and Garakpass in Kelardasht region, northern Iran. The highest SOC storages were determined in coniferous forest land uses (SF1=255.00 and SF2=237.90 Mg C ha−1 followed by deciduous forest (PF1=216.74 and PF2=159.12 Mg C ha−1 and abandoned rangeland (AR1=185.31 and AR2=151.60 Mg C ha−1. Land use changes showed significant impacts on soil CO2 efflux. The significant positive correlations, with exponential and linear relationships were observed between the monthly CO2 emissions; the minimum air temperature and the cumulative precipitation in the last week ended to CO2 measurement time. The highest recorded soil CO2 efflux in a wide range of land uses were obtained in August to October due to more suitable temperature and rainfall distribution. Based on lower CO2 emission in abandoned rangelands, lesser soil organic carbon is related to lower input to soil. The higher C: N ratios in litter and some of mineral horizons (SF2 and lower CO2 emissions by the higher lignin and polyphenol concentrations (SF1 in coniferous forests compared to deciduous forests have probably caused increasing SOC storage.

  15. CO2 capture and storage in Greece: A case study from komotini ngcc power plant

    Directory of Open Access Journals (Sweden)

    Koukouzas Nikolaos


    Full Text Available The aim of this paper is to examine the possibilities for the abatement of CO2 emissions in the Greek fossil fuel power generation sector. An overview of CO2 capture, transportation, and storage concepts, on which the R&D community is focused, is presented. The implementation of post-combustion CO2 capture options in an existing fossil fuel power plant is then examined and the consequences on the overall plant performance are determined. Finally, the possibilities of transportation and then underground storage of the pure CO2 stream are analyzed taking into account both technical and economical factors. The results of this analysis show that CO2 sequestration is technically feasible for existing fossil fuel fired power plants in Greece. However, substantial reduction in plant efficiency is observed due to increased energy demand of the technologies used as well as in electricity production cost due to capital and operation costs of capture, transport, and storage of CO2. .

  16. Environmental Assessment for Potential Impacts of Ocean CO2 Storage on Marine Biogeochemical Cycles (United States)

    Yamada, N.; Tsurushima, N.; Suzumura, M.; Shibamoto, Y.; Harada, K.


    Ocean CO2 storage that actively utilizes the ocean potential to dissolve extremely large amounts of CO2 is a useful option with the intent of diminishing atmospheric CO2 concentration. CO2 storage into sub-seabed geological formations is also considered as the option which has been already put to practical reconnaissance in some projects. Direct release of CO2 in the ocean storage and potential CO2 leakage from geological formations into the bottom water can alter carbonate system as well as pH of seawater. It is essential to examine to what direction and extent chemistry change of seawater induced by CO2 can affect the marine environments. Previous studies have shown direct and acute effects by increasing CO2 concentrations on physiology of marine organisms. It is also a serious concern that chemistry change can affect the rates of chemical, biochemical and microbial processes in seawater resulting in significant influences on marine biogeochemical cycles of the bioelements including carbon, nutrients and trace metals. We, AIST, have conducted a series of basic researches to assess the potential impacts of ocean CO2 storage on marine biogeochemical processes including CaCO3 dissolution, and bacterial and enzymatic decomposition of organic matter. By laboratory experiments using a special high pressure apparatus, the improved empirical equation was obtained for CaCO3 dissolution rate in the high CO2 concentrations. Based on the experimentally obtained kinetics with a numerical simulation for a practical scenario of oceanic CO2 sequestration where 50 Mton CO2 per year is continuously injected to 1,000-2,500 m depth within 100 x 333 km area for 30 years, we could illustrate precise 3-D maps for the predicted distributions of the saturation depth of CaCO3, in situ Ω value and CaCO3 dissolution rate in the western North Pacific. The result showed no significant change in the bathypelagic CaCO3 flux due to chemistry change induced by ocean CO2 sequestration. Both

  17. Geomechanical effects of CO2 storage in depleted gas reservoirs in the Netherlands: Inferences from feasibility studies and comparison with aquifer storage

    NARCIS (Netherlands)

    Orlic, B.


    In this paper, the geomechanical impact of large-scale carbon dioxide (CO2) storage in depleted Dutch gas fields is compared with the impact of CO2 storage in saline aquifers. The geomechanical behaviour of four potential CO2 storage sites is examined using flow and geomechanical simulations. Many

  18. Dynamic characterization of fractured carbonates at the Hontomín CO2 storage site (United States)

    Le Gallo, yann; de Dios, José Carlos; Salvador, Ignacio; Acosta Carballo, Taimara


    The geological storage of CO2 is investigated at the Technology Development Plant (TDP) at Hontomín (Burgos, Spain) into a deep saline aquifer, formed by fractured carbonates with poor matrix porosity. During the hydraulic characterization tests, 2,300 tons of liquid CO2 and 14,000 m3 synthetic brine were co-injected on site in various sequences to determine the pressure and temperature responses of the facture network. The results of the pressure tests were analyzed using an analytical approach to determine the overall petrophysical characteristics of the storage formation. Later on, these characteristics were implemented in a 3-D numerical model. The model is a compositional dual medium (fracture + matrix) which accounts for temperature effects, as CO2 is liquid at the well bottom-hole, and multiphase flow hysteresis as alternating water and CO2 injection tests were performed. The pressure and temperature responses of the storage formation were history-matched mainly through the petrophysical and geometrical characteristics of the facture network. This dynamic characterization of the fracture network controls the CO2 migration while the matrix does not appear to significantly contribute to the storage capacity. Consequently, the hydrodynamic behavior of the aquifer is one of the main challenge of the modeling workflow.

  19. 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.


    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


    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Melanie; Schlasner, Steven; Sorensen, James; Hamling, John


    Carbon dioxide (CO2) is produced in large quantities during electricity generation and by industrial processes. These CO2 streams vary in terms of both composition and mass flow rate, sometimes substantially. The impact of a varying CO2 stream on pipeline and storage operation is not fully understood in terms of either operability or infrastructure robustness. This study was performed to summarize basic background from the literature on the topic of operational flexibility of CO2 transport and storage, but the primary focus was on compiling real-world lessons learned about flexible operation of CO2 pipelines and storage from both large-scale field demonstrations and commercial operating experience. Modeling and pilot-scale results of research in this area were included to illustrate some of the questions that exist relative to operation of carbon capture and storage (CCS) projects with variable CO2 streams. It is hoped that this report’s real-world findings provide readers with useful information on the topic of transport and storage of variable CO2 streams. The real-world results were obtained from two sources. The first source consisted of five full-scale, commercial transport–storage projects: Sleipner, Snøhvit, In Salah, Weyburn, and Illinois Basin–Decatur. These scenarios were reviewed to determine the information that is available about CO2 stream variability/intermittency on these demonstration-scale projects. The five projects all experienced mass flow variability or an interruption in flow. In each case, pipeline and/or injection engineers were able to accommodate any issues that arose. Significant variability in composition has not been an issue at these five sites. The second source of real- world results was telephone interviews conducted with experts in CO2 pipeline transport, injection, and storage during which commercial anecdotal information was acquired to augment that found during the literature search of the five full-scale projects. The

  1. Nanoscale Chemical Processes Affecting Storage Capacities and Seals during Geologic CO2 Sequestration. (United States)

    Jun, Young-Shin; Zhang, Lijie; Min, Yujia; Li, Qingyun


    Geologic CO2 sequestration (GCS) is a promising strategy to mitigate anthropogenic CO2 emission to the atmosphere. Suitable geologic storage sites should have a porous reservoir rock zone where injected CO2 can displace brine and be stored in pores, and an impermeable zone on top of reservoir rocks to hinder upward movement of buoyant CO2. The injection wells (steel casings encased in concrete) pass through these geologic zones and lead CO2 to the desired zones. In subsurface environments, CO2 is reactive as both a supercritical (sc) phase and aqueous (aq) species. Its nanoscale chemical reactions with geomedia and wellbores are closely related to the safety and efficiency of CO2 storage. For example, the injection pressure is determined by the wettability and permeability of geomedia, which can be sensitive to nanoscale mineral-fluid interactions; the sealing safety of the injection sites is affected by the opening and closing of fractures in caprocks and the alteration of wellbore integrity caused by nanoscale chemical reactions; and the time scale for CO2 mineralization is also largely dependent on the chemical reactivities of the reservoir rocks. Therefore, nanoscale chemical processes can influence the hydrogeological and mechanical properties of geomedia, such as their wettability, permeability, mechanical strength, and fracturing. This Account reviews our group's work on nanoscale chemical reactions and their qualitative impacts on seal integrity and storage capacity at GCS sites from four points of view. First, studies on dissolution of feldspar, an important reservoir rock constituent, and subsequent secondary mineral precipitation are discussed, focusing on the effects of feldspar crystallography, cations, and sulfate anions. Second, interfacial reactions between caprock and brine are introduced using model clay minerals, with focuses on the effects of water chemistries (salinity and organic ligands) and water content on mineral dissolution and surface

  2. Next generation of CO2 enhanced water recovery with subsurface energy storage in China (United States)

    Li, Qi; Kühn, Michael; Ma, Jianli; Niu, Zhiyong


    Carbon dioxide (CO2) utilization and storage (CCUS) is very popular in comparison with traditional CO2 capture and storage (CCS) in China. In particular, CO2 storage in deep saline aquifers with enhanced water recovery (CO2-EWR) [1] is gaining more and more attention as a cleaner production technology. The CO2-EWR was written into the "U.S.-China Joint Announcement on Climate Change" released November 11, 2014. "Both sides will work to manage climate change by demonstrating a new frontier for CO2 use through a carbon capture, use, and sequestration (CCUS) project that will capture and store CO2 while producing fresh water, thus demonstrating power generation as a net producer of water instead of a water consumer. This CCUS project with enhanced water recovery will eventually inject about 1.0 million tonnes of CO2 and create approximately 1.4 million cubic meters of freshwater per year." In this article, at first we reviewed the history of the CO2-EWR and addressed its current status in China. Then, we put forth a new generation of the CO2-EWR with emphasizing the collaborative solutions between carbon emission reductions and subsurface energy storage or renewable energy cycle [2]. Furthermore, we figured out the key challenging problems such as water-CCUS nexus when integrating the CO2-EWR with the coal chemical industry in the Junggar Basin, Xinjiang, China [3-5]. Finally, we addressed some crucial problems and strategic consideration of the CO2-EWR in China with focuses on its technical bottleneck, relative advantage, early opportunities, environmental synergies and other related issues. This research is not only very useful for the current development of CCUS in the relative "cold season" but also beneficial for the energy security and clean production in China. [1] Li Q, Wei Y-N, Liu G, Shi H (2015) CO2-EWR: a cleaner solution for coal chemical industry in China. Journal of Cleaner Production 103:330-337. doi:10.1016/j.jclepro.2014.09.073 [2] Streibel M

  3. Detection of CO2 leaks from carbon capture and storage sites to the atmosphere with combined CO2 and O2 measurements (United States)

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


    One of the main issues in carbon capture and storage (CCS) is the possibility of leakage of CO2 from the storage reservoir to the atmosphere, both from a public health and a climate change combat perspective. Detecting these leaks in the atmosphere is difficult due to the rapid mixing of the emitted CO2 with the surrounding air masses and the high natural variability of the atmospheric CO2 concentration. Instead of measuring only the CO2 concentration of the atmosphere, its isotopes or chemical tracers that are released together with the CO2, our method uses O2 measurements in addition to CO2 measurements to detect a leak from a CCS site. CO2 and O2 are coupled in most processes on earth. In photosynthesis, plants take up CO2 and release O2 at the same time. In respiration and fossil fuel burning, O2 is consumed while CO2 is released. In case of a leak from a CCS site, however, there is no relationship between CO2 and O2. A CO2 leak can therefore be distinguished from other sources of CO2 by looking at the atmospheric CO2-O2 ratio. A natural increase of the CO2 concentration is accompanied by a drop in the O2 concentration, while an increase in the CO2 concentration caused by a leak from a CCS site does not have any effect on the O2 concentration. To demonstrate this leak detection strategy we designed and built a transportable CO2 and O2 measurement system, that is capable of measuring the relatively minute (ppm's variations on a 21% concentration) changes in the O2 concentration. The system comprises of three cases that contain the instrumentation and gas handling equipment, the gas cylinders used as reference and calibration gases and a drying system, respectively. Air is pumped to the system from an air inlet that is placed in a small tower in the field. At the conference, we will demonstrate the success of leak detection with our system by showing measurements of several CO2 release experiments, where CO2 was released at a small distance from the air inlet of

  4. Geochemical Implications of CO2 Leakage Associated with Geologic Storage: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, Omar R.; Qafoku, Nikolla; Cantrell, Kirk J.; Brown, Christopher F.


    Leakage from deep storage reservoirs is a major risk factor associated with geologic sequestration of carbon dioxide (CO2). Different scientific theories exist concerning the potential implications of such leakage for near-surface environments. The authors of this report reviewed the current literature on how CO2 leakage (from storage reservoirs) would likely impact the geochemistry of near surface environments such as potable water aquifers and the vadose zone. Experimental and modeling studies highlighted the potential for both beneficial (e.g., CO2 re sequestration or contaminant immobilization) and deleterious (e.g., contaminant mobilization) consequences of CO2 intrusion in these systems. Current knowledge gaps, including the role of CO2-induced changes in redox conditions, the influence of CO2 influx rate, gas composition, organic matter content and microorganisms are discussed in terms of their potential influence on pertinent geochemical processes and the potential for beneficial or deleterious outcomes. Geochemical modeling was used to systematically highlight why closing these knowledge gaps are pivotal. A framework for studying and assessing consequences associated with each factor is also presented in Section 5.6.

  5. 3rd Sino-German Conference “Underground Storage of CO2 and Energy”

    CERN Document Server

    Xie, Heping; Were, Patrick


    Anthropogenic greenhouse gas emissions, energy security and sustainability are three of the greatest contemporary global challenges today. This year the Sino-German Cooperation Group “Underground Storage of CO2 and Energy”, is meeting on the 21-23 May 2013 for the second time in Goslar, Germany, to convene its 3rd Sino-German conference on the theme “Clean Energy Systems in the Subsurface: Production, Storage and Conversion”.   This volume is a collection of diverse quality scientific works from different perspectives elucidating on the current developments in CO2 geologic sequestration research to reduce greenhouse emissions including measures to monitor surface leakage, groundwater quality and the integrity of caprock, while ensuring a sufficient supply of clean energy. The contributions herein have been structured into 6 major thematic research themes: Integrated Energy and Environmental Utilization of Geo-reservoirs: Law, Risk Management & Monitoring CO2 for Enhanced Gas and Oil Recovery, Coa...

  6. Performance Analysis of Cold Energy Recovery from CO2 Injection in Ship-Based Carbon Capture and Storage (CCS)


    Hwalong You; Youngkyun Seo; Cheol Huh; Daejun Chang


    Carbon capture and storage (CCS) technology is one of the practical solutions for mitigating the effects of global warming. When captured CO 2 is injected into storage sites, the CO 2 is subjected to a heating process. In a conventional CO 2 injection system, CO 2 cold energy is wasted during this heating process. This study proposes a new CO 2 injection system that takes advantage of the cold energy using the Rankine cycle. The study compared the conventional system with the new CO 2 injecti...

  7. Keynote speech - Corrective measures for CO2 storage - The MiReCOL project

    NARCIS (Netherlands)

    Neele, F.


    CO2 capture, transport and storage (CCS) has the potential to significantly reduce the carbon emission that follows from the use of fossil fuels in power production and industry. Integrated demo-scale projects are currently being developed to demonstrate the feasibility of CCS and the first such

  8. Estimates of CO2 traffic emissions from mobile concentration measurements (United States)

    Maness, H. L.; Thurlow, M. E.; McDonald, B. C.; Harley, R. A.


    We present data from a new mobile system intended to aid in the design of upcoming urban CO2-monitoring networks. Our collected data include GPS probe data, video-derived traffic density, and accurate CO2 concentration measurements. The method described here is economical, scalable, and self-contained, allowing for potential future deployment in locations without existing traffic infrastructure or vehicle fleet information. Using a test data set collected on California Highway 24 over a 2 week period, we observe that on-road CO2 concentrations are elevated by a factor of 2 in congestion compared to free-flow conditions. This result is found to be consistent with a model including vehicle-induced turbulence and standard engine physics. In contrast to surface concentrations, surface emissions are found to be relatively insensitive to congestion. We next use our model for CO2 concentration together with our data to independently derive vehicle emission rate parameters. Parameters scaling the leading four emission rate terms are found to be within 25% of those expected for a typical passenger car fleet, enabling us to derive instantaneous emission rates directly from our data that compare generally favorably to predictive models presented in the literature. The present results highlight the importance of high spatial and temporal resolution traffic data for interpreting on- and near-road concentration measurements. Future work will focus on transport and the integration of mobile platforms into existing stationary network designs.

  9. A model for estimating CO2 solubility in aqueous alkanolamines

    DEFF Research Database (Denmark)

    Gabrielsen, Jostein; Michelsen, Michael Locht; Stenby, Erling Halfdan


    Partial pressures of carbon dioxide (CO2) over aqueous solutions of monoethanolamine (MEA), diethanolamine (DEA), and N-methyldiethanolamine (MDEA) have been correlated using a simple approach where only one chemical equilibrium reaction is taken into account and assuming ideal gas and ideal liqu...

  10. Streamline-based Simulation of Geological CO2 Storage: Otway Case-Study (United States)

    Lazaro Vallejo, Lorena; Dance, Tess; Cinar, Yildiray; Laforce, Tara


    Three of the most important challenges for the near future: maximizing oil extraction, securing fresh water supplies and mitigating climate change through Carbon Capture and Storage (CCS), require a better understanding of flow in porous media. It has been shown by Qi et al [1] that an optimum injection strategy for CO2 storage can result in up to 90% of the injected CO2 being trapped in the pore network of the rock during the injection phase of a CO2 storage project. When the non-wetting phase saturation increases and then decreases in the pore space, part of the non-wetting phase is trapped in pores as a residual saturation. Injection of CO2 and water in alternating cycles can be used to engineer this trapping. With time, CO2 will dissolve in the brine surrounding it and finally precipitate as carbonate. The Otway Project, taking place in the south-east of Australia and lead by the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC), is the world's largest research and geosequestration demonstration project [2]. CO2CRC has proposed testing the concept of using residual trapping to improve storage security by using Huff and Push injections. In this case, CO2 is injected in a depleted gas reservoir together with methane. The Huff and Push injection mechanism consists of a single well which alternates injection and production. Initially, brine is injected followed by a mixture of CO2/CH4/other gases (77/20/3 mole%) followed by a shut-in period. Then, when production starts the water front should move faster towards the production well and immobilise CO2 in the micro pores of the rock. Very little production of CO2 should be observed, confirming that it has been immobilized within the formation. Traditional grid-based reservoir simulations are used to predict fluid behaviour and to design injection strategies that maximize both oil extraction and trapping of carbon dioxide in the rock formation. Unlike conventional grid-based simulations, streamline

  11. Comparative methane estimation from cattle based on total CO2 production using different techniques

    Directory of Open Access Journals (Sweden)

    Md N. Haque


    Full Text Available The objective of this study was to compare the precision of CH4 estimates using calculated CO2 (HP by the CO2 method (CO2T and measured CO2 in the respiration chamber (CO2R. The CO2R and CO2T study was conducted as a 3 × 3 Latin square design where 3 Dexter heifers were allocated to metabolic cages for 3 periods. Each period consisted of 2 weeks of adaptation followed by 1 week of measurement with the CO2R and CO2T. The average body weight of the heifer was 226 ± 11 kg (means ± SD. They were fed a total mixed ration, twice daily, with 1 of 3 supplements: wheat (W, molasses (M, or molasses mixed with sodium bicarbonate (Mbic. The dry mater intake (DMI; kg/day was significantly greater (P < 0.001 in the metabolic cage compared with that in the respiration chamber. The daily CH4 (L/day emission was strongly correlated (r = 0.78 between CO2T and CO2R. The daily CH4 (L/kg DMI emission by the CO2T was in the same magnitude as by the CO2R. The measured CO2 (L/day production in the respiration chamber was not different (P = 0.39 from the calculated CO2 production using the CO2T. This result concludes a reasonable accuracy and precision of CH4 estimation by the CO2T compared with the CO2R.

  12. PVTxy properties of CO2 mixtures relevant for CO2 capture, transport and storage: Review of available experimental data and theoretical models


    Li, Hailong; Jakobsen, Jana P.; Wilhelmsen, Øivind; Yan, Jinyue


    The knowledge about pressure–volume–temperature–composition (PVTxy) properties plays an importantrole in the design and operation of many processes involved in CO2 capture and storage (CCS) systems.A literature survey was conducted on both the available experimental data and the theoreticalmodels associated with the thermodynamic properties of CO2 mixtures within the operation windowof CCS. Some gaps were identified between available experimental data and requirements of the systemdesign and ...

  13. The impact of elevated CO2 concentrations on soil microbial community, soil organic matter storage and nutrient cycling at a natural CO2 vent in NW Bohemia (United States)

    Nowak, Martin; Beulig, Felix; von Fischer, Joe; Muhr, Jan; Kuesel, Kirsten; Trumbore, Susan


    Natural CO2 vents or 'mofettes' are diffusive or advective exhalations of geogenic CO2 from soils. These structures occur at several places worldwide and in most cases they are linked to volcanic activity. Characteristic for mofette soils are high CO2 concentrations of up to more than 90% as well as a lack of oxygen, low pH values and reducing conditions. Mofette soils usually are considered to be sites of carbon accumulation, which is not only due to the absence of oxygen, but might also result from lower plant litter quality due to CO2 fertilization of CO2 influenced plants and reduced availability of N and P for the decomposer community. Furthermore, fermentation processes and the formation of reduced elements by anoxic decomposition might fuel chemo-lithoautotrophic or mixotrophic microbial CO2 uptake, a process which might have important ecological functions by closing internal element cycles, formation of trace gasses as well as by re-cycling and storing of carbon. Several studies of microbial community structure revealed a shift towards CO2 utilizing prokaryotes in moffete soils compared to a reference site. Here, we use combined stable and radiocarbon isotope data from mofette soils in NW Bohemia to quantify the contribution of geogenic CO2 to soil organic carbon formation within mofette soils, either resulting from plant litter or from microbial CO2 uptake. This is possible because the geogenic CO2 has a distinct isotopic signature (δ13C = -2 o Δ14C = -1000 ) that is very different from the isotopic signature of atmospheric CO2. First results show that mofette soils have a high Corg content (20 to 40 %) compared to a reference site (2 to 20 %) and soil organic matter is enriched in 13C as well as depleted in 14C. This indicates that geogenic CO2 is re-fixed and stored as SOM. In order to quantify microbial contribution to CO2 fixation and SOM storage, microbial CO2 uptake rates were determined by incubating mofette soils with 13CO2 labelled gas. The

  14. N2-CO2 co-injection field test at the Ketzin pilot CO2 storage site


    Sebastian Fischer; Martin Zimmer; Alexandra Szizybalski; Christian Kujawa; B. Plessen; A. Liebscher; F. Moeller;  & the Ketzin Team


    In summer 2013, a four week N2-CO2 co-injection field test was conducted at the Ketzin pilot site. Major objectives were (i) demonstrating the technical feasibility of a continuous N2-CO2 co-injection scenario, (ii) monitoring wellhead and reservoir pressure, (iii) monitoring spreading and behavior of the CO2-N2 gas mixture in the reservoir, and (iv) analyzing potential chromatographic effects within the reservoir. 10,000 L (10 Nm3) of krypton (Kr) were injected as an additional conservative ...

  15. Assessment of the potential for geological storage of CO2 in the vicinity of Moneypoint, Co. Clare, Ireland

    NARCIS (Netherlands)

    Farrelly, I.; Loske, B.; Neele, F.; Holdstock, M.


    The largest single point CO2 emitter in Ireland, the Moneypoint Power Station (3.95 Mt CO2 per annum), is located in Co. Clare and geologically lies within the Clare Basin. In terms of the economics of transportation of CO2 from Moneypoint, a possible local storage site would be favoured. The study

  16. Preliminary assessments of CO2 storage in carbonate formations: a case study from Malaysia (United States)

    Raza, Arshad; Gholami, Raoof; Rezaee, Reza; Bing, Chua Han; Nagarajan, Ramasamy; Hamid, Mohamed Ali


    The preliminary assessment of depleted reservoirs prior to the injection of CO2 is an essential step to ensure the safety and success of storage projects. Several studies have provided a preliminary assessment of depleted reservoirs as a sequestration practice. However, the screening criteria used in these studies were not able to consider all of the aspects of a storage site. The aim of this paper is to provide a reservoir-scale evaluation approach for long-term storage practice in an offshore carbonate field located in Malaysia. Recently developed screening criteria that cover the key aspects of storage sites, such as capacity, injectivity, trapping mechanisms, and containment, are taken into consideration for the purpose of this study. The results obtained suggest that the reservoir has good potential to be a storage place for CO2, although the compaction behavior and aquifer supports of the reservoir might cause some difficulties. It is, therefore, recommended that a series of experimental and numerical studies on different aspects of storage sites be performed to ensure that injectivity is not a problem when it comes to the implementation stage.

  17. Capturing Coupled Effects of CO2 and Brine Leakage in Cemented Wellbores at CO2 Storage Sites using Decoupled Reduced Order Models (United States)

    Harp, D. R.; Carey, J. W.; Pawar, R.


    Understanding the potential significance and risk of CO2 and brine leakage from wells at proposed geologic storage sites is a key goal of the National Risk Assessment Partnership (NRAP). In this study, we developed reduced order models (ROMs) of cemented-wellbore leakage that are being incorporated into systems models in order to determine CO2 storage risk profiles. ROMs are used to capture general trends in numerically simulated leakage in a computationally efficient manner, allowing for large numbers of evaluations required by stochastic evaluations of risk. In this study, we perform the wellbore leakage numerical simulations using the multi-phase Finite Element Heat and Mass (FEHM) code. The constituents of interest are water, supercritical CO2, dissolved CO2, liquid CO2, and gaseous CO2. The computational domain is a full 3D mesh with a 0.1 m wellbore at the center. A storage reservoir is located below the impermeable rock and the wellbore is connected directly to the atmosphere or to a shallow aquifer above. Injector wells introduce CO2 into the reservoir for 20 years followed by a 30 year relaxation period. Reservoir depth, cement permeability, relative permeability model parameters, and injection rate are sampled by Latin Hypercube sampling. For each sample, simulations are performed with and without a wellbore in the model. Transient pressures and CO2 saturations are collected at the top of the reservoir at the location where the wellbore would be located from the model without a wellbore. CO2 and brine flow rates (leakage) are collected near the top of the wellbore from the models with a wellbore. ROM model inputs are the sampled parameters, transient pressures and CO2 saturations and their first and second derivatives calculated by backward finite differences. Using these inputs, ROMs are generated for CO2 and brine leakage using the Multivariate Adaptive Regression Splines (MARS) regression technique. ROM development, evaluation, and use will be

  18. Storage of Renewable Energy by Reduction of CO2 with Hydrogen. (United States)

    Züttel, Andreas; Mauron, Philippe; Kato, Shunsuke; Callini, Elsa; Holzer, Marco; Huang, Jianmei


    The main difference between the past energy economy during the industrialization period which was mainly based on mining of fossil fuels, e.g. coal, oil and methane and the future energy economy based on renewable energy is the requirement for storage of the energy fluxes. Renewable energy, except biomass, appears in time- and location-dependent energy fluxes as heat or electricity upon conversion. Storage and transport of energy requires a high energy density and has to be realized in a closed materials cycle. The hydrogen cycle, i.e. production of hydrogen from water by renewable energy, storage and use of hydrogen in fuel cells, combustion engines or turbines, is a closed cycle. However, the hydrogen density in a storage system is limited to 20 mass% and 150 kg/m(3) which limits the energy density to about half of the energy density in fossil fuels. Introducing CO(2) into the cycle and storing hydrogen by the reduction of CO(2) to hydrocarbons allows renewable energy to be converted into synthetic fuels with the same energy density as fossil fuels. The resulting cycle is a closed cycle (CO(2) neutral) if CO(2) is extracted from the atmosphere. Today's technology allows CO(2) to be reduced either by the Sabatier reaction to methane, by the reversed water gas shift reaction to CO and further reduction of CO by the Fischer-Tropsch synthesis (FTS) to hydrocarbons or over methanol to gasoline. The overall process can only be realized on a very large scale, because the large number of by-products of FTS requires the use of a refinery. Therefore, a well-controlled reaction to a specific product is required for the efficient conversion of renewable energy (electricity) into an easy to store liquid hydrocarbon (fuel). In order to realize a closed hydrocarbon cycle the two major challenges are to extract CO(2) from the atmosphere close to the thermodynamic limit and to reduce CO(2) with hydrogen in a controlled reaction to a specific hydrocarbon. Nanomaterials with

  19. Pore-scale modeling of wettability effects on CO2-brine displacement during geological storage (United States)

    Basirat, Farzad; Yang, Zhibing; Niemi, Auli


    Wetting properties of reservoir rocks and caprocks can vary significantly, and they strongly influence geological storage of carbon dioxide in deep saline aquifers, during which CO2 is supposed to displace the resident brine and to become permanently trapped. Fundamental understanding of the effect of wettability on CO2-brine displacement is thus important for improving storage efficiency and security. In this study, we investigate the influence of wetting properties on two-phase flow of CO2 and brine at the pore scale. A numerical model based on the phase field method is implemented to simulate the two-phase flow of CO2-brine in a realistic pore geometry. Our focus is to study the pore-scale fluid-fluid displacement mechanisms under different wetting conditions and to quantify the effect of wettability on macroscopic parameters such as residual brine saturation, capillary pressure, relative permeability, and specific interfacial area. Our simulation results confirm that both the trapped wetting phase saturation and the normalized interfacial area increase with decreasing contact angle. However, the wetting condition does not appear to influence the CO2 breakthrough time and saturation. We also show that the macroscopic capillary pressures based on the pressure difference between inlet and outlet can differ significantly from the phase averaging capillary pressures for all contact angles when the capillary number is high (log Ca > -5). This indicates that the inlet-outlet pressure difference may not be a good measure of the continuum-scale capillary pressure. In addition, the results show that the relative permeability of CO2 can be significantly lower in strongly water-wet conditions than in the intermediate-wet conditions.

  20. Identification and determination of trapping parameters as key site parameters for CO2 storage for the active CO2 storage site in Ketzin (Germany) - Comparison of different experimental approaches and analysis of field data (United States)

    Zemke, Kornelia; Liebscher, Axel


    Petrophysical properties like porosity and permeability are key parameters for a safe long-term storage of CO2 but also for the injection operation itself. The accurate quantification of residual trapping is difficult, but very important for both storage containment security and storage capacity; it is also an important parameter for dynamic simulation. The German CO2 pilot storage in Ketzin is a Triassic saline aquifer with initial conditions of the target sandstone horizon of 33.5 ° C/6.1 MPa at 630 m. One injection and two observation wells were drilled in 2007 and nearly 200 m of core material was recovered for site characterization. From June 2008 to September 2013, slightly more than 67 kt food-grade CO2 has been injected and continuously monitored. A fourth observation well has been drilled after 61 kt injected CO2 in summer 2012 at only 25 m distance to the injection well and new core material was recovered that allow study CO2 induced changes in petrophysical properties. The observed only minor differences between pre-injection and post-injection petrophysical parameters of the heterogeneous formation have no severe consequences on reservoir and cap rock integrity or on the injection behavior. Residual brine saturation for the Ketzin reservoir core material was estimated by different methods. Brine-CO2 flooding experiments for two reservoir samples resulted in 36% and 55% residual brine saturation (Kiessling, 2011). Centrifuge capillary pressure measurements (pc = 0.22 MPa) yielded the smallest residual brine saturation values with ~20% for the lower part of the reservoir sandstone and ~28% for the upper part (Fleury, 2010). The method by Cerepi (2002), which calculates the residual mercury saturation after pressure release on the imbibition path as trapped porosity and the retracted mercury volume as free porosity, yielded unrealistic low free porosity values of only a few percent, because over 80% of the penetrated mercury remained in the samples after

  1. Dynamic Behavior of CO2 in a Wellbore and Storage Formation: Wellbore-Coupled and Salt-Precipitation Processes during Geologic CO2 Sequestration

    Directory of Open Access Journals (Sweden)

    Jize Piao


    Full Text Available For investigating the wellbore flow process in CO2 injection scenarios, coupled wellbore-reservoir (WR and conventional equivalent porous media (EPM models were compared with each other. In WR model, during the injection, conditions for the wellbore including pressure and temperature were dynamically changed from the initial pressure (7.45–8.33 MPa and temperature (52.0–55.9°C of the storage formation. After 3.35 days, the wellbore flow reached the steady state with adiabatic condition; temperature linearly increased from the well-head (35°C to the well-bottom (52°C. In contrast, the EPM model neglecting the wellbore process revealed that CO2 temperature was consistently 35°C at the screen interval. Differences in temperature from WR and EPM models resulted in density contrast of CO2 that entered the storage formation (~200 and ~600 kg/m3, resp.. Subsequently, the WR model causing greater density difference between CO2 and brine revealed more vertical CO2 migration and counterflow of brine and also developed the localized salt-precipitation. Finally, a series of sensitivity analyses for the WR model was conducted to assess how the injection conditions influenced interplay between flow system and the localized salt-precipitation in the storage formation.

  2. A data driven model for the impact of IFT and density variations on CO2 storage capacity in geologic formations (United States)

    Nomeli, Mohammad A.; Riaz, Amir


    Carbon dioxide (CO2) storage in depleted hydrocarbon reservoirs and deep saline aquifers is one of the most promising solutions for decreasing CO2 concentration in the atmosphere. One of the important issues for CO2 storage in subsurface environments is the sealing efficiency of low-permeable cap-rocks overlying potential CO2 storage reservoirs. Though we focus on the effect of IFT in this study as a factor influencing sealing efficiency or storage capacity, other factors such as interfacial interactions, wettability, pore radius and interfacial mass transfer also affect the mobility and storage capacity of CO2 phase in the pore space. The study of the variation of IFT is however important because the pressure needed to penetrate a pore depends on both the pore size and the interfacial tension. Hence small variations in IFT can affect flow across a large population of pores. A novel model is proposed to find the IFT of the ternary systems (CO2/brine-salt) in a range of temperatures (300-373 K), pressures (50-250 bar), and up to 6 molal salinity applicable to CO2 storage in geological formations through a multi-variant non-linear regression of experimental data. The method uses a general empirical model for the quaternary system CO2/brine-salts that can be made to coincide with experimental data for a variety of solutions. We introduce correction parameters into the model, which compensates for uncertainties, and enforce agreement with experimental data. The results for IFT show a strong dependence on temperature, pressure, and salinity. The model has been found to describe the experimental data in the appropriate parameter space with reasonable precision. Finally, we use the new model to evaluate the effects of formation depth on the actual efficiency of CO2 storage. The results indicate that, in the case of CO2 storage in deep subsurface environments as a global-warming mitigation strategy, CO2 storage capacity increases with reservoir depth.

  3. Change in cap rock porosity triggered by pressure and temperature dependent CO2–water–rock interactions in CO2 storage systems

    Directory of Open Access Journals (Sweden)

    Christina Hemme


    Full Text Available Carbon capture and storage in deep geological formations is a method to reduce greenhouse gas emissions. Supercritical CO2 is injected into a reservoir and dissolves in the brine. Under the impact of pressure and temperature (P–T the aqueous species of the CO2-acidified brine diffuse through the cap rock where they trigger CO2–water–rock interactions. These geochemical reactions result in mineral dissolution and precipitation along the CO2 migration path and are responsible for a change in porosity and therefore for the sealing capacity of the cap rock. This study focuses on the diffusive mass transport of CO2 along a gradient of decreasing P–T conditions. The process is retraced with a one-dimensional hydrogeochemical reactive mass transport model. The semi-generic hydrogeochemical model is based on chemical equilibrium thermodynamics. Based on a broad variety of scenarios, including different initial mineralogical, chemical and physical parameters, the hydrogeochemical parameters that are most sensitive for safe long-term CO2 storage are identified. The results demonstrate that P–T conditions have the strongest effect on the change in porosity and the effect of both is stronger at high P–T conditions because the solubility of the mineral phases involved depends on P–T conditions. Furthermore, modeling results indicate that the change in porosity depends strongly on the initial mineralogical composition of the reservoir and cap rock as well as on the brine compositions. Nevertheless, a wide range of conditions for safe CO2 storage is identified.

  4. Dynamic Fluid Flow and Geomechanical Coupling to Assess the CO2 Storage Integrity in Faulted Structures

    Directory of Open Access Journals (Sweden)

    Baroni A.


    Full Text Available The SiteChar research on the Southern Adriatic Sea site focused on the investigation of the geomechanical and hydrodynamic behaviour of the storage complex in the case of CO2 injection in a reservoir consisting of fractured carbonate formations. Special attention was paid to the effects that natural faults and fractures might have on CO2 migration, and the effects that injection might have on the stability of faults. This assessment was originally performed via a hydro-geomechanical one-way coupling which relies on an adequate representation of faults in the model, allowing one to simulate fluid flow along the fault plane and inside faults as well as evolution of the stress state due to CO2 injection. The geological model was populated with petrophysical and geomechanical parameters derived either from laboratory measurements performed on samples from a reservoir analogue, or published literature. Since only sparse data were available, various scenarios were simulated to take into account the uncertainties in the fluid flow and geomechanical properties of the model: the different state of faults (i.e., open or closed and various in situ stress state, commonly named geostatic stresses as the earth’s crust deformation is assumed to be slow regarding the short-term study. Various fluid flow parameters were also considered, although only one set of petrophysical data corresponding to the most realistic ones is considered here. Faults modeled as volumetric elements behave as flow pathways for fluids when they are conductive. The injected CO2 migrates inside and through the Rovesti fault, which is located near the injection well. The fluid flow also induces overpressure in the faults. The overpressure in the Rovesti fault reaches 2.2 MPa while it reaches 4.4 MPa at the bottom hole of the injector. Extending to about 30 km, the pore pressure field reaches the Gondola fault located at 15 km from the injection zone but the overpressure does not exceed

  5. ULTimateCO2 project: Field experiment in an underground rock laboratory to study the well integrity in the context of CO2 geological storage

    NARCIS (Netherlands)

    Manceau, J.C.; Audigane, P.; Claret, F.; Parmentier, M.; Tambach, T.J.; Wasch, L.; Gherardi, F.; Dimier, A.; Ukelis, O.; Jeandel, E.; Cladt, F.; Zorn, R.; Yalamas, T.; Nussbaum, C.; Laurent, A.; Fierz, T.; Pieedevache, M.


    Wells drilled through low-permeable caprock are potential connections between the CO2 storage reservoir and overlying sensitive targets like aquifers and targets located at the surface. The wellbore integrity can be compromised due to in situ operations, including drilling, completion, operations

  6. Techno-economic assessment of four CO2 storage sites = Évaluation technico-économique de quatre sites de stockage de CO2

    NARCIS (Netherlands)

    Gruson, J.F.; Serbutoviez, S.; Delprat-Jannaud, F.; Akhurst, M.; Nielsen, C.; Dalhoff, F.; Bergmo, P.; Bos, C.; Volpi, V.; Iacobellis, S.


    Carbon Capture and Storage (CCS) should be a key technology in order to achieve a decline in the CO2 emissions intensity of the power sector and other intensive industry, but this potential deployment could be restricted by cost issues as the International Energy Agency (IEA) in their last

  7. Geochemical Impacts of Leaking CO2 from Subsurface Storage Reservoirs to Unconfined and Confined Aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Qafoku, Nikolla; Brown, Christopher F.; Wang, Guohui; Sullivan, E. C.; Lawter, Amanda R.; Harvey, Omar R.; Bowden, Mark


    Experimental research work has been conducted and is undergoing at Pacific Northwest National Laboratory (PNNL) to address a variety of scientific issues related with the potential leaks of the carbon dioxide (CO2) gas from deep storage reservoirs. The main objectives of this work are as follows: • Develop a systematic understanding of how CO2 leakage is likely to influence pertinent geochemical processes (e.g., dissolution/precipitation, sorption/desorption and redox reactions) in the aquifer sediments. • Identify prevailing environmental conditions that would dictate one geochemical outcome over another. • Gather useful information to support site selection, risk assessment, policy-making, and public education efforts associated with geological carbon sequestration. In this report, we present results from experiments conducted at PNNL to address research issues related to the main objectives of this effort. A series of batch and column experiments and solid phase characterization studies (quantitative x-ray diffraction and wet chemical extractions with a concentrated acid) were conducted with representative rocks and sediments from an unconfined, oxidizing carbonate aquifer, i.e., Edwards aquifer in Texas, and a confined aquifer, i.e., the High Plains aquifer in Kansas. These materials were exposed to a CO2 gas stream simulating CO2 gas leaking scenarios, and changes in aqueous phase pH and chemical composition were measured in liquid and effluent samples collected at pre-determined experimental times. Additional research to be conducted during the current fiscal year will further validate these results and will address other important remaining issues. Results from these experimental efforts will provide valuable insights for the development of site-specific, generation III reduced order models. In addition, results will initially serve as input parameters during model calibration runs and, ultimately, will be used to test model predictive capability and

  8. A fast and robust TOUGH2 module to simulate geological CO2 storage in saline aquifers (United States)

    Shabani, Babak; Vilcáez, Javier


    A new TOUGH2 module to simulate geological CO2 storage (GCS) in saline aquifers is developed based on the widely employed ECO2N module of TOUGH2. The newly developed TOUGH2 module uses a new non-iterative fugacity-activity thermodynamic model to obtain the partitioning of CO2 and H2O between the aqueous and gas phases. Simple but robust thermophysical correlations are used to obtain density, viscosity, and enthalpy of the gas phase. The implementation and accuracy of the employed thermophysical correlations are verified by comparisons against the national institute of standards and technology (NIST) online thermophysical database. To assess the computation accuracy and efficiency, simulation results obtained with the new TOUGH2 module for a one-dimensional non-isothermal radial and a three-dimensional isothermal system are compared against the simulation results obtained with the ECO2N module. Treating salt mass fraction in the aqueous phase as a constant, along with the inclusion of a non-iterative fugacity-activity thermodynamic model, and simple thermophysical correlations, resulted in simulations much faster than simulations with ECO2N module, without losing numerical accuracy. Both modules yield virtually identical results. Additional field-scale simulations of CO2 injection into an actual non-isothermal and heterogeneous geological formation confirmed that the new module is much faster than the ECO2N module in simulating complex field-scale conditions. Owing to its capability to handle CO2-CH4-H2S-N2 gas mixtures and its compatibility with TOUGHREACT, this new TOUGH2 module offers the possibility of developing a fast and robust TOUGHREACT module to predict the fate of CO2 in GCS sites under biotic conditions where CO2, CH4, H2S, and N2 gases can be formed.

  9. Geochemical modeling of fluid-fluid and fluid-mineral interactions during geological CO2 storage (United States)

    Zhu, C.; Ji, X.; Lu, P.


    The long time required for effective CO2 storage makes geochemical modeling an indispensable tool for CCUS. One area of geochemical modeling research that is in urgent need is impurities in CO2 streams. Permitting impurities, such as H2S, in CO2 streams can lead to potential capital and energy savings. However, predicting the consequences of co-injection of CO2 and impurities into geological formations requires the understanding of the phase equilibrium and fluid-fluid interactions. To meet this need, we developed a statistical associating fluid theory (SAFT)-based equation of state (EOS) for the H2S-CO2-H2O-NaCl system at 373.15 concentration of NaCl up to 6 mol/kgH2O. The EoS allows us to predict equilibrium composition in both liquid and vapor phases, fugacity coefficients of components, and phase densities. Predictions show that inclusion of H2S in CO2 streams may lead to two-phase flow in pipelines. For H2S-CO2 mixtures at a given temperature the bubble and dew pressures decrease with increasing H2S content, while the mass density increases at low pressures and decreases at high pressures. Furthermore, the EoS can be incorporated into reservoir simulators so that the dynamic development of mixed fluid plumes in the reservoir can be simulated. Accurate modeling of fluid-mineral interactions must confront unresolved uncertainties of silicate dissolution - precipitation reaction kinetics. Most prominent among these uncertainties is the well-known lab-field apparent discrepancy in dissolution rates. Although reactive transport models that simulate the interactions between reservoir rocks and brine, and their attendant effects on porosity and permeability changes, have proliferated, whether these results have acceptable uncertainties are unknown. We have conducted a series of batch experiments at elevated temperatures and numerical simulations of coupled dissolution and precipitation reactions. The results show that taking into account of reaction coupling is able

  10. Assessment of model estimates of land-atmosphere CO2 exchange across northern Eurasia (United States)

    Rawlins, M.A.; McGuire, A.D.; Kimball, J.S.; Dass, P.; Lawrence, D.; Burke, E.; Chen, X.; Delire, C.; Koven, C.; MacDougall, A.; Peng, S.; Rinke, A.; Saito, K.; Zhang, W.; Alkama, R.; Bohn, T. J.; Ciais, P.; Decharme, B.; Gouttevin, I.; Hajima, T.; Ji, D.; Krinner, G.; Lettenmaier, D.P.; Miller, P.; Moore, J.C.; Smith, B.; Sueyoshi, T.


    A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobilization of permafrost soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO2) cycling through analysis of net ecosystem productivity (NEP) and its component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time, simulated by a set of land surface models (LSMs) over a region spanning the drainage basin of Northern Eurasia. The retrospective simulations cover the period 1960–2009 at 0.5° resolution, which is a scale common among many global carbon and climate model simulations. Model performance benchmarks were drawn from comparisons against both observed CO2 fluxes derived from site-based eddy covariance measurements as well as regional-scale GPP estimates based on satellite remote-sensing data. The site-based comparisons depict a tendency for overestimates in GPP and ER for several of the models, particularly at the two sites to the south. For several models the spatial pattern in GPP explains less than half the variance in the MODIS MOD17 GPP product. Across the models NEP increases by as little as 0.01 to as much as 0.79 g C m−2 yr−2, equivalent to 3 to 340 % of the respective model means, over the analysis period. For the multimodel average the increase is 135 % of the mean from the first to last 10 years of record (1960–1969 vs. 2000–2009), with a weakening CO2 sink over the latter decades. Vegetation net primary productivity increased by 8 to 30 % from the first to last 10 years, contributing to soil carbon storage gains. The range in regional mean NEP among the group is twice the multimodel mean, indicative of the uncertainty in CO2 sink strength. The models simulate that inputs to the soil carbon pool exceeded losses, resulting in a net soil carbon gain amid a decrease in residence time. Our analysis points to improvements in model

  11. Assessment of model estimates of land-atmosphere CO2 exchange across Northern Eurasia (United States)

    Rawlins, M. A.; McGuire, A. D.; Kimball, J. S.; Dass, P.; Lawrence, D.; Burke, E.; Chen, X.; Delire, C.; Koven, C.; MacDougall, A.; Peng, S.; Rinke, A.; Saito, K.; Zhang, W.; Alkama, R.; Bohn, T. J.; Ciais, P.; Decharme, B.; Gouttevin, I.; Hajima, T.; Ji, D.; Krinner, G.; Lettenmaier, D. P.; Miller, P.; Moore, J. C.; Smith, B.; Sueyoshi, T.


    A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobilization of permafrost soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO2) cycling through analysis of net ecosystem productivity (NEP) and its component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time, simulated by a set of land surface models (LSMs) over a region spanning the drainage basin of Northern Eurasia. The retrospective simulations cover the period 1960-2009 at 0.5° resolution, which is a scale common among many global carbon and climate model simulations. Model performance benchmarks were drawn from comparisons against both observed CO2 fluxes derived from site-based eddy covariance measurements as well as regional-scale GPP estimates based on satellite remote-sensing data. The site-based comparisons depict a tendency for overestimates in GPP and ER for several of the models, particularly at the two sites to the south. For several models the spatial pattern in GPP explains less than half the variance in the MODIS MOD17 GPP product. Across the models NEP increases by as little as 0.01 to as much as 0.79 g C m-2 yr-2, equivalent to 3 to 340 % of the respective model means, over the analysis period. For the multimodel average the increase is 135 % of the mean from the first to last 10 years of record (1960-1969 vs. 2000-2009), with a weakening CO2 sink over the latter decades. Vegetation net primary productivity increased by 8 to 30 % from the first to last 10 years, contributing to soil carbon storage gains. The range in regional mean NEP among the group is twice the multimodel mean, indicative of the uncertainty in CO2 sink strength. The models simulate that inputs to the soil carbon pool exceeded losses, resulting in a net soil carbon gain amid a decrease in residence time. Our analysis points to improvements in model elements

  12. CO2 Geological Storage in Olivine Rich Basaltic Aquifers: New Insights From Flow-Through Experiments (United States)

    Peuble, S.; Godard, M.; Luquot, L.; Gouze, P.


    Injection of CO2-rich fluids into basaltic aquifers is one of the methods envisaged for mitigation of increasing atmospheric CO2. Basalts are rich in Mg, Fe and Ca and have a high potential to trap CO2 as carbonate minerals. However, the role of reaction-transport processes has yet to be investigated in order to predict the capacity and sustainability for CO2 storage of these highly reactive systems. We present the results of three flow-through experiments performed at 180°C and total pressure 12 MPa. NaHCO3 rich water (0.5 mol/L) mixed with CO2 (PCO2 = 10 MPa) was injected through sintered analogues of olivine-accumulation zones in basaltic flows (~ 95% olivine Fo87, MORB glass, minor chromite). The injection rate was 1 mL/h for exp. 1 and 2, and 0.1 mL/h for exp. 3. The initial porosity and permeability of samples ranges from 3 to 7% and 250.10-18 to 2500.10-18 m2 respectively. All experiments show a strong permeability decrease (down to 10-18 m2) after 90 hours for exp. 1 and 2, earlier for exp 3. Yet dissolution occurs: high concentrations of Zr and Al and of Co in the outlet fluids indicate dissolution of basaltic glass and olivine respectively. Si concentration changes reveal a more complex system with olivine dissolution and the precipitation of Si rich phases: we observed the growth of relatively large (up to 5 microns) Mg-Fe rich phyllosilicates mostly perpendicular to olivine surface. This reaction is typically associated to hydration of (ultra-)mafic rocks and may explain the decrease in permeability during experiments. Finally, the low Ca and Mg fluid concentrations suggest trapping by Ca-Mg rich phases. Ankerite and dolomite were identified by Raman spectrometry in the reacted samples after exp. 1 and 2, while exp. 3 was characterized by precipitation of well-developed and abundant magnesite (Mg0.88 Fe0.11 Ca0.01 CO3) replacing dissolved olivine. Carbonation appears to be an efficient process: ~ 0.015g of CO2 per gram of sample is stored as carbonates

  13. The potential of renewables versus natural gas with CO2 capture and storage for power generation under CO2 constraints

    NARCIS (Netherlands)

    Van Den Broek, Machteld; Berghout, Niels; Rubin, Edward S.


    The costs of intermittent renewable energy systems (IRES) and power storage technologies are compared on a level playing field to those of natural gas combined cycle power plants with CO2 capture and storage (NGCC-CCS). To account for technological progress over time, an "experience

  14. Impure CO2 geological storage: Preliminary laboratory experiments at ambient conditions (United States)

    Oostrom, M.; Wei, N.; Wang, Y.; Zhang, C.; Bonneville, A.


    The cost of carbon capture is related to the purity of the CO2 and subsequent removal of the impurities may be costly. For several sites, it is likely to be more cost effective if impure CO2 is injected, although non-condensable impurities may reduce storage capacity and increase the injection pressure. The feasibility of co-sequestration of CO2 with a certain level of impurity has not been experimentally studied in much detail due to severe limitations associated with visualization and sampling at high pressure and temperature conditions. A series of intermediate-scale experiments has been conducted in a 100-cm-long, 20-cm-high, and 5-cm-wide intermediate-scale flow cell studying the effects of N2 and H2S impurities on CO2 transport in initially brine-saturated porous media. Homogeneous and simple layered heterogeneous systems were used to evaluate pH behavior, measure water and gas pressures, and analyze the gas composition at several locations. A multiphase code was used to compare simulation results for equilibrium dissolution conditions with experimental results. Although these preliminary analogue experiments were conducted at ambient pressure and temperature, the provide insight in the behavior of injected multi-component gas in initially saturated porous media.

  15. Probabilistic modeling and global sensitivity analysis for CO 2 storage in geological formations: a spectral approach

    KAUST Repository

    Saad, Bilal Mohammed


    This work focuses on the simulation of CO2 storage in deep underground formations under uncertainty and seeks to understand the impact of uncertainties in reservoir properties on CO2 leakage. To simulate the process, a non-isothermal two-phase two-component flow system with equilibrium phase exchange is used. Since model evaluations are computationally intensive, instead of traditional Monte Carlo methods, we rely on polynomial chaos (PC) expansions for representation of the stochastic model response. A non-intrusive approach is used to determine the PC coefficients. We establish the accuracy of the PC representations within a reasonable error threshold through systematic convergence studies. In addition to characterizing the distributions of model observables, we compute probabilities of excess CO2 leakage. Moreover, we consider the injection rate as a design parameter and compute an optimum injection rate that ensures that the risk of excess pressure buildup at the leaky well remains below acceptable levels. We also provide a comprehensive analysis of sensitivities of CO2 leakage, where we compute the contributions of the random parameters, and their interactions, to the variance by computing first, second, and total order Sobol’ indices.

  16. Geoelectrical image of the subsurface for CO2 geological storage in the Changhua site, Taiwan (United States)

    Chiang, C. W.; Chiao, C. H.; Yang, M. W.; Yu, C. W.; Yang, C. H.; Chen, C. C.


    Global warming has recently become an important worldwide issue. Reduction of carbon dioxide (CO2) emission is recommended by Intergovernmental Panel on Climate Change, which geological storage is one of possible way to reduce the CO2 issue. The Taichung Power Plant is a coal-fired power plant operated by the Taiwan Power Company in Taichung, Taiwan, which is the largest coal-fired power station in the world. The power plant emits approximately 40 million tons annually which is also the world's largest CO2 emitter. Geophysical techniques are presented as the most useful tool to characterize the reservoir. The electrical resistivity tool was carried out applying audio-magnetotelluric (AMT) method, which could provide the depth resolution for evaluating the subsurface. A first survey of 20 AMT soundings was acquired to study the viability of the method to characterize the subsurface. Stations were deployed at approximately 500 m intervals and the data were recorded in the frequency range of 104-100 Hz. The dimensionality analysis proved the validity of the 1-D or 2-D assumption. The visualized model shows a layered electrical resistivity structure from shallow to depth of 3000 m. The preliminary result corresponds to seismic reflection and geological investigations that suggests a simple geological structure without complex geological processes in the area. It could be a suitable site for geological storage.

  17. The seasonal variation of the CO2 flux over Tropical Asia estimated from GOSAT, CONTRAIL, and IASI

    NARCIS (Netherlands)

    Basu, S.; Krol, M.C.; Butz, A.; Clerbaux, C.; Sawa, Y.; Machida, T.; Matsueda, H.; Frankenberg, C.; Hasekamp, O.P.; Aben, I.


    We estimate the CO2 flux over Tropical Asia in 2009, 2010, and 2011 using Greenhouse Gases Observing Satellite (GOSAT) total column CO2(XCO2) and in situ measurements of CO2. Compared to flux estimates from assimilating surface measurements of CO2, GOSAT XCO2 estimates a more dynamic seasonal cycle

  18. U.S. Department of Energy's site screening, site selection, and initial characterization for storage of CO2 in deep geological formations (United States)

    Rodosta, T.D.; Litynski, J.T.; Plasynski, S.I.; Hickman, S.; Frailey, S.; Myer, L.


    The U.S. Department of Energy (DOE) is the lead Federal agency for the development and deployment of carbon sequestration technologies. As part of its mission to facilitate technology transfer and develop guidelines from lessons learned, DOE is developing a series of best practice manuals (BPMs) for carbon capture and storage (CCS). The "Site Screening, Site Selection, and Initial Characterization for Storage of CO2 in Deep Geological Formations" BPM is a compilation of best practices and includes flowchart diagrams illustrating the general decision making process for Site Screening, Site Selection, and Initial Characterization. The BPM integrates the knowledge gained from various programmatic efforts, with particular emphasis on the Characterization Phase through pilot-scale CO2 injection testing of the Validation Phase of the Regional Carbon Sequestration Partnership (RCSP) Initiative. Key geologic and surface elements that suitable candidate storage sites should possess are identified, along with example Site Screening, Site Selection, and Initial Characterization protocols for large-scale geologic storage projects located across diverse geologic and regional settings. This manual has been written as a working document, establishing a framework and methodology for proper site selection for CO2 geologic storage. This will be useful for future CO2 emitters, transporters, and storage providers. It will also be of use in informing local, regional, state, and national governmental agencies of best practices in proper sequestration site selection. Furthermore, it will educate the inquisitive general public on options and processes for geologic CO2 storage. In addition to providing best practices, the manual presents a geologic storage resource and capacity classification system. The system provides a "standard" to communicate storage and capacity estimates, uncertainty and project development risk, data guidelines and analyses for adequate site characterization, and

  19. Does saturation with supercritical CO2 alter the frictional properties of Na-montmorillonite (SWy-2)? Implications for CO2 storage reservoirs (United States)

    Samuelson, J. E.


    Recent research indicates that saturation with supercritical CO2 results in swelling of Na-montmorillonite in a similar fashion to water induced swelling, though to a lesser extent. It is important for feasibility studies of geological CO2 storage to understand if clay-rich fault zones in storage reservoirs will become frictionally weaker or stronger, and whether frictional stability will be altered due to the saturation with CO2. We performed velocity-stepping direct shear experiments on pre-pressed plates (49 mm long x 35 mm wide x ~1 mm thick), of Na-montmorillonite (SWy-2). An effective normal stress of 35 MPa was used in all experiments, which is roughly equivalent to the effective overburden stress expected in many storage projects. Temperature was held constant at ~48 °C, consistent with previous experiments which indicated CO2 induced swelling in Na-montmorillonite. Pore fluid conditions were varied, with the frictional strength measured for oven-dry (attached to vacuum) gouges, and gouges saturated with deionized (DI) water, and oven-dry saturated with supercritical CO2. Pore pressure was maintained at 15 MPa for the water and CO2 saturated experiments (σn=50 MPa, PH20/CO2=15 MPa). Shearing velocity was varied systematically from approximately 11 μm/s to 0.2, 1.1, 11, 1.1, and 0.2 μm/s in order to determine the rate and state friction parameters, a, b, and DC. Additionally, microstructural analysis of the post-shear clay gouges will be conducted in an effort to understand the rheology behind changes observed in frictional properties. Preliminary experiments show an overconsolidation peak at strains of approximately 0.2-0.7 for all experimental conditions. Peak friction (μP) for oven-dry samples is ~0.56, decaying to a steady-state friction (μSS) ranging from 0.52-0.55. DI-saturated samples indicate μP=0.13-0.14 and μSS=0.11-0.12. Early results on CO2 saturated samples indicate modest weakening when compared to oven-dry samples, but also that part

  20. CO2 Storage Properties of Nanostructured Carbons by a Microwave Plasma Reactor

    Directory of Open Access Journals (Sweden)

    Mi Tian


    Full Text Available Nanostructured carbon was successfully produced by methane cracking in a relatively low-energy cold plasma reactor designed in-house. A followed thermal treatment was carried out to further enhance its porosity. The modified plasma carbon was then employed for CO2 adsorption at 25°C. The as-synthesized plasma carbon and the modified carbon were characterized by BET surface area/pore size analyzer, Raman spectra, and transmission electron microscopy (TEM. The results show thermal modification pronouncedly improves BET surface area and porosity of PC due to opening up of accessible micro-/mesopores in the graphitic structure and by the removal of amorphous carbons around the graphite surface. The modified PC displays a higher adsorption capacity at 25°C than that of the commercial activated carbon reported. The low hydrogen storage capacity of the modified PC indicates that it can be considered for CO2 removal in syngas.

  1. Correction: Large-scale electricity storage utilizing reversible solid oxide cells combined with underground storage of CO2 and CH4

    DEFF Research Database (Denmark)

    Jensen, Søren Højgaard; Graves, Christopher R.; Mogensen, Mogens Bjerg


    Correction for ‘Large-scale electricity storage utilizing reversible solid oxide cells combined with underground storage of CO2 and CH4’ by S. H. Jensen et al., Energy Environ. Sci., 2015, 8, 2471–2479.......Correction for ‘Large-scale electricity storage utilizing reversible solid oxide cells combined with underground storage of CO2 and CH4’ by S. H. Jensen et al., Energy Environ. Sci., 2015, 8, 2471–2479....

  2. Fractionation of carbon isotopes by phytoplankton and estimates of ancient CO2 levels (United States)

    Freeman, K. H.; Hayes, J. M.


    Reports of the 13C content of marine particulate organic carbon are compiled and on the basis of GEOSECS data and temperatures, concentrations, and isotopic compositions of dissolved CO2 in the waters in which the related phytoplankton grew are estimated. In this way, the fractionation of carbon isotopes during photosynthetic fixation of CO2 is found to be significantly correlated with concentrations of dissolved CO2. Because ancient carbon isotopic fractionations have been determined from analyses of sedimentary porphyrins [Popp et al., 1989], the relationship between isotopic fractionation and concentrations of dissolved CO2 developed here can be employed to estimate concentrations of CO2 dissolved in ancient oceans and, in turn, partial pressures of CO2 in ancient atmospheres. The calculations take into account the temperature dependence of chemical and isotopic equilibria in the dissolved-inorganic-carbon system and of air-sea equilibria. Paleoenvironmental temperatures for each sample are estimated from reconstructions of paleogeography, latitudinal temperature gradients, and secular changes in low-latitude sea surface temperature. It is estimated that atmospheric partial pressures of CO2 were over 1000 micro atm 160 - 100 Ma ago, then declined to values near 300 micro atm during the next 100 Ma. Analysis of a high-resolution record of carbon isotopic fractionation at the Cenomanian-Turonian boundary suggests that the partial pressure of CO2 in the atmosphere was drawn down from values near 840 micro atm to values near 700 micro atm during the anoxic event.

  3. A layer stripping approach for monitoring CO2 storage sites using surface magnetotelluric responses (United States)

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


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

  4. Framework for the assessment of interaction between CO2 geological storage and other sedimentary basin resources. (United States)

    Michael, K; Whittaker, S; Varma, S; Bekele, E; Langhi, L; Hodgkinson, J; Harris, B


    Sedimentary basins around the world considered suitable for carbon storage usually contain other natural resources such as petroleum, coal, geothermal energy and groundwater. Storing carbon dioxide in geological formations in the basins adds to the competition for access to the subsurface and the use of pore space where other resource-based industries also operate. Managing potential impacts that industrial-scale injection of carbon dioxide may have on other resource development must be focused to prevent potential conflicts and enhance synergies where possible. Such a sustainable coexistence of various resource developments can be accomplished by implementing a Framework for Basin Resource Management strategy (FBRM). The FBRM strategy utilizes the concept of an Area of Review (AOR) for guiding development and regulation of CO2 geological storage projects and for assessing their potential impact on other resources. The AOR is determined by the expected physical distribution of the CO2 plume in the subsurface and the modelled extent of reservoir pressure increase resulting from the injection of the CO2. This information is used to define the region to be characterised and monitored for a CO2 injection project. The geological characterisation and risk- and performance-based monitoring will be most comprehensive within the region of the reservoir containing the carbon dioxide plume and should consider geological features and wells continuously above the plume through to its surface projection; this region defines where increases in reservoir pressure will be greatest and where potential for unplanned migration of carbon dioxide is highest. Beyond the expanse of the carbon dioxide plume, geological characterisation and monitoring should focus only on identified features that could be a potential migration conduit for either formation water or carbon dioxide.

  5. Mesoscale Assessment of CO2 Storage Potential and Geological Suitability for Target Area Selection in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Yujie Diao


    Full Text Available In China, south of the Yangtze River, there are a large number of carbon sources, while the Sichuan Basin is the largest sedimentary basin; it makes sense to select the targets for CO2 geological storage (CGUS early demonstration. For CO2 enhanced oil and gas, coal bed methane recovery (CO2-EOR, EGR, and ECBM, or storage in these depleted fields, the existing oil, gas fields, or coal seams could be the target areas in the mesoscale. This paper proposed a methodology of GIS superimposed multisource information assessment of geological suitability for CO2 enhanced water recovery (CO2-EWR or only storage in deep saline aquifers. The potential per unit area of deep saline aquifers CO2 storage in Central Sichuan is generally greater than 50 × 104 t/km2 at P50 probability level, with Xujiahe group being the main reservoir. CO2 storage potential of depleted gas fields is 53.73 × 108 t, while it is 33.85 × 108 t by using CO2-EGR technology. This paper recommended that early implementation of CGUS could be carried out in the deep saline aquifers and depleted gas fields in the Sichuan Basin, especially that of the latter because of excellent traps, rich geological data, and well-run infrastructures.

  6. Modeling Diffusion and Buoyancy-Driven Convection with Application to Geological CO2 Storage

    KAUST Repository

    Allen, Rebecca


    ABSTRACT Modeling Diffusion and Buoyancy-Driven Convection with Application to Geological CO2 Storage Rebecca Allen Geological CO2 storage is an engineering feat that has been undertaken around the world for more than two decades, thus accurate modeling of flow and transport behavior is of practical importance. Diffusive and convective transport are relevant processes for buoyancy-driven convection of CO2 into underlying fluid, a scenario that has received the attention of numerous modeling studies. While most studies focus on Darcy-scale modeling of this scenario, relatively little work exists at the pore-scale. In this work, properties evaluated at the pore-scale are used to investigate the transport behavior modeled at the Darcy-scale. We compute permeability and two different forms of tortuosity, namely hydraulic and diffusive. By generating various pore ge- ometries, we find hydraulic and diffusive tortuosity can be quantitatively different in the same pore geometry by up to a factor of ten. As such, we emphasize that these tortuosities should not be used interchangeably. We find pore geometries that are characterized by anisotropic permeability can also exhibit anisotropic diffusive tortuosity. This finding has important implications for buoyancy-driven convection modeling; when representing the geological formation with an anisotropic permeabil- ity, it is more realistic to also account for an anisotropic diffusivity. By implementing a non-dimensional model that includes both a vertically and horizontally orientated 5 Rayleigh number, we interpret our findings according to the combined effect of the anisotropy from permeability and diffusive tortuosity. In particular, we observe the Rayleigh ratio may either dampen or enhance the diffusing front, and our simulation data is used to express the time of convective onset as a function of the Rayleigh ratio. Also, we implement a lattice Boltzmann model for thermal convective flows, which we treat as an analog for

  7. CO2 Geological Storage in Olivine Rich Basaltic Aquifers: New Insights From Flow-Through Experiments (United States)

    Peuble, S.; Godard, M.; Luquot, L.; Gibert, B.; Mainprice, D.; Martinez, I.; Gouze, P.


    Injection of CO2-rich fluids into (ultra-)mafic aquifers is one of the methods envisaged for mitigation of increasing atmospheric CO2 concentrations. These rocks, rich in Mg, Fe and Ca, have a high potential to trap CO2 as carbonates minerals. However, the role of reaction-transport processes has not been investigated to predict the capacity and sustainability for CO2 storage in these highly reactive systems. We performed three percolation-reaction experiments on the ICARE-2 bench (Luquot et al., 2012) at 180°C and total pressure of 12 MPa. NaHCO3 rich water (0.5 mol/L) mixed with CO2 (Pco2 = 10 MPa) were injected at an initial injection rate of 1 mL/h for exp. 1 and 2, and 0.1 mL/h for exp. 3 into sintered olivine analogues of accumulation zones in basaltic flows. The sintered samples comprise mainly olivine Fo87 (Mg1.75Fe0.24Ni0.01SiO4) with minor basalt and spinel (Mg0.57Cr1.19Ti0.03Mn0.01Fe0.66Al0.54O4). The initial porosity and permeability of samples ranges from 4 to 7 % and 30x10-18 to 400x10-18 m2 respectively. All experiments resulted in a strong permeability decrease (down to 10-18 m2) after 90 hours for exp. 1 and 2 and 55 hours for exp 3. The enrichment in several major and trace elements observed in outlet fluids indicates that dissolution of olivine (Si, Co), basalt (Al, Zr) and spinel (Cr, V) occurred, while the depleted Ca and Mg composition of outlet fluids indicates precipitation of Ca-Mg rich phases. Analyses of reacted samples indicate that all basalt grains were dissolved and the spatial distribution of etch pits on forsterite surfaces suggest the anisotropic dissolution of olivine. Ankerite and calcite is observed in pores of samples after exp. 1 and 2, and well-developed magnesite (Mg0.88Fe0.11Ca0.01CO3) and dolomite replacing dissolved olivine is found in exp.3 sample. The (001) planes of magnesite and dolomite are parallel to the (100) plane of forsterite. Downstream, no carbonates were found but the growth of relatively large (up to 5 µm

  8. CMS: CO2 Signals Estimated for Fossil Fuel Emissions and Biosphere Flux, California (United States)

    National Aeronautics and Space Administration — This data set provides estimated CO2 emission signals for 16 regions (air quality basins) in California, USA, during the individual months of November 2010 and May...

  9. Public Responses to CO2 Storage Sites. Lessons from Five European Cases

    Energy Technology Data Exchange (ETDEWEB)

    Oltra, C.; Boso, A. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas CIEMAT, Madrid (Spain); Upham, P. [Finnish Environment Institute, Helsinki and Centre for Integrated Energy Research, University of Leeds, Leeds (United Kingdom); Riesch, H. [Centre for Environmental Policy, Imperial College London, London (United Kingdom); Brunsting, S. [ECN Policy Studies, Energy Research Centre of the Netherlands ECN, Amsterdam (Netherlands); Duetschke, E. [Fraunhofer-Institut fuer System- und Innovationsforschung ISI, Karlsruhe (Germany); Lis, A. [Department of Sociology and Social Anthropology, Central European University, Budapest (Hungary)


    Studies of the factors involved in public perceptions of CO2 storage projects reveal a level of complexity and diversity that arguably confounds a comprehensive theoretical account. To some extent, a conceptual approach that simply organises the relevant social scientific knowledge thematically, rather than seeking an integrated explanation, is as useful as any single account that fails to do justice to the contingencies involved. This paper reviews and assembles such knowledge in terms of six themes and applies these themes to five European cases of carbon capture and storage (CCS) implementation. We identify the main factors involved in community responses to CCS as relating to: the characteristics of the project; the engagement process; risk perceptions; the actions of the stakeholders; the characteristics of the community, and the socio-political context.

  10. Influence of Chemical, Mechanical, and Transport Processes on Wellbore Leakage from Geologic CO2Storage Reservoirs. (United States)

    Carroll, Susan A; Iyer, Jaisree; Walsh, Stuart D C


    Wells are considered to be high-risk pathways for fluid leakage from geologic CO 2 storage reservoirs, because breaches in this engineered system have the potential to connect the reservoir to groundwater resources and the atmosphere. Given these concerns, a few studies have assessed leakage risk by evaluating regulatory records, often self-reported, documenting leakage in gas fields. Leakage is thought to be governed largely by initial well-construction quality and the method of well abandonment. The geologic carbon storage community has raised further concerns because acidic fluids in the CO 2 storage reservoir, alkaline cement meant to isolate the reservoir fluids from the overlying strata, and steel casings in wells are inherently reactive systems. This is of particular concern for storage of CO 2 in depleted oil and gas reservoirs with numerous legacy wells engineered to variable standards. Research suggests that leakage risks are not as great as initially perceived because chemical and mechanical alteration of cement has the capacity to seal damaged zones. Our work centers on defining the coupled chemical and mechanical processes governing flow in damaged zones in wells. We have developed process-based models, constrained by experiments, to better understand and forecast leakage risk. Leakage pathways can be sealed by precipitation of carbonate minerals in the fractures and deformation of the reacted cement. High reactivity of cement hydroxides releases excess calcium that can precipitate as carbonate solids in the fracture network under low brine flow rates. If the flow is fast, then the brine remains undersaturated with respect to the solubility of calcium carbonate minerals, and zones depleted in calcium hydroxides, enriched in calcium carbonate precipitates, and made of amorphous silicates leached of original cement minerals are formed. Under confining pressure, the reacted cement is compressed, which reduces permeability and lowers leakage risks. The

  11. Adaptive management for subsurface pressure and plume control in application to geological CO2 storage (United States)

    Gonzalez-Nicolas, A.; Cihan, A.; Birkholzer, J. T.; Petrusak, R.; Zhou, Q.; Riestenberg, D. E.; Trautz, R. C.; Godec, M.


    Industrial-scale injection of CO2 into the subsurface can cause reservoir pressure increases that must be properly controlled to prevent any potential environmental impact. Excessive pressure buildup in reservoir may result in ground water contamination stemming from leakage through conductive pathways, such as improperly plugged abandoned wells or distant faults, and the potential for fault reactivation and possibly seal breaching. Brine extraction is a viable approach for managing formation pressure, effective stress, and plume movement during industrial-scale CO2 injection projects. The main objectives of this study are to investigate suitable different pressure management strategies involving active brine extraction and passive pressure relief wells. Adaptive optimized management of CO2 storage projects utilizes the advanced automated optimization algorithms and suitable process models. The adaptive management integrates monitoring, forward modeling, inversion modeling and optimization through an iterative process. In this study, we employ an adaptive framework to understand primarily the effects of initial site characterization and frequency of the model update (calibration) and optimization calculations for controlling extraction rates based on the monitoring data on the accuracy and the success of the management without violating pressure buildup constraints in the subsurface reservoir system. We will present results of applying the adaptive framework to test appropriateness of different management strategies for a realistic field injection project.

  12. Assessing the potential of utilisation and storage strategies for post-combustion CO2 emissions reduction

    Directory of Open Access Journals (Sweden)

    Peter eStyring


    Full Text Available The emissions reduction potential of three carbon dioxide handling strategies for post-combustion capture are considered. These are carbon capture and sequestration/storage (CCS, enhanced hydrocarbon recovery (EHR and carbon dioxide utilization (CDU to produce synthetic oil. This is performed using common and comparable boundary conditions including net CO2 sequestered based on equivalent boundary conditions. This is achieved using a 'cradle to grave approach' where the final destination and fate of any product is considered. The input boundary is pure CO2 that has been produced using a post-combustion capture process as this is common between all processes. The output boundary is the emissions resulting from any product produced with the assumption that the majority of the oil will go to combustion processes. We also consider the 'cradle to gate' approach where the ultimate fate of the oil is not considered as this is a boundary condition often applied to EHR processes. Results show that while CCS can make an impact on CO2 emissions, CDU will have a comparable effect whilst generating income while EHR will ultimately increase net emissions. The global capacity for CDU is also compared against CCS using data based on current and planned CCS projects. Analysis shows that current CDU represent a greater volume of capture than CCS processes and that this gap is likely to remain well beyond 2020 which is the limit of the CCS projects in the database.

  13. Functional response of a near-surface soil microbial community to a simulated underground CO2 storage leak.

    Directory of Open Access Journals (Sweden)

    Sergio E Morales

    Full Text Available Understanding the impacts of leaks from geologic carbon sequestration, also known as carbon capture and storage, is key to developing effective strategies for carbon dioxide (CO2 emissions management and mitigation of potential negative effects. Here, we provide the first report on the potential effects of leaks from carbon capture and storage sites on microbial functional groups in surface and near-surface soils. Using a simulated subsurface CO2 storage leak scenario, we demonstrate how CO2 flow upward through the soil column altered both the abundance (DNA and activity (mRNA of microbial functional groups mediating carbon and nitrogen transformations. These microbial responses were found to be seasonally dependent and correlated to shifts in atmospheric conditions. While both DNA and mRNA levels were affected by elevated CO2, they did not react equally, suggesting two separate mechanisms for soil microbial community response to high CO2 levels. The results did not always agree with previous studies on elevated atmospheric (rather than subsurface CO2 using FACE (Free-Air CO2 Enrichment systems, suggesting that microbial community response to CO2 seepage from the subsurface might differ from its response to atmospheric CO2 increases.

  14. The environmental impact and risk assessment of CO2 capture, transport and storage - an evaluation of the knowledge base

    NARCIS (Netherlands)

    Koornneef, J.M.; Ramirez, C.A.; Turkenburg, W.C.; Faaij, A.P.C.


    In this study, we identify and characterize known and new environmental consequences associated with CO2 capture from power plants, transport by pipeline and storage in geological formations. We have reviewed (analogous) environmental impact assessment procedures and scientific literature on

  15. Characterization and modelling of a naturally fractured reservoir-caprock unit targeted for CO2 storage in arctic Norway

    NARCIS (Netherlands)

    Senger, K.; Mulrooney, M.; Schaaf, N.; Tveranger, J.; Braathen, A.; Ogata, K.; Olaussen, S.


    Successfully storing CO2 underground requires a good understanding of the subsurface at the storage site, and its robust representation in geological models. Geological models, and related simulations, provide important quantitative information on critical parameters for the optimal utilisation of

  16. Diffusive leakage of brine from aquifers during CO2 geological storage (United States)

    Dejam, Morteza; Hassanzadeh, Hassan


    The area of investigation in this study is designed around an improved understanding of fundamentals of the diffusive leakage of brine from a storage aquifer into overlying and underlying low permeability layers during geosequestration of carbon dioxide (CO2) through development of a theoretical model. Here, we consider a two-dimensional domain in cylindrical coordinates, comprised of an aquifer and an overburden, where the interaction between the two media is handled by imposing the continuities of pressures and fluid fluxes at the aquifer-overburden interface. This coupled problem is solved by successive implementation of the Laplace and finite Hankel transforms. The developed solutions can be used to analyze diffusive leakage of brine from the aquifer into overburden and generate type curves for average pressures in the aquifer and overburden during injection and post injection periods. The results show that the leakage rate at early times is scaled with t1/2 while it remains constant at late times. It is also shown that the average pressure in the aquifer is scaled with t for short and long times. Moreover, the average pressure in the overburden is scaled with t at late times while it is scaled with t3/2 at early times. In addition, the results reveal that factors affecting diffusive leakage rate through intact overburden during CO2 storage are, in decreasing order of significance, thickness of overburden, thickness of aquifer, aquifer to overburden permeability ratio, and aquifer to overburden porosity ratio. However, thickness of aquifer has minimal effect on diffusive leakage of brine within post injection period. To evaluate the theoretical model, case studies for two potential sites in United Kingdom, one in Lincolnshire and the other one in the Firth of Forth, are conducted. The field studies show that the diffusive leakage from the aquifer into the overburden diminishes ∼40 years after the injection has ceased for Lincolnshire while it stops after

  17. Radon isotope measurements as a monitoring tool for CO2 leakage in geological storage (United States)

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


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

  18. The importance of CO2 capture and storage: A geopolitical discussion

    Directory of Open Access Journals (Sweden)

    Johnsson Filip


    Full Text Available The CO2 capture and storage (CCS technology is since more than ten years considered one of the key options for the future climate change mitigation. This paper discusses the implications for the further development of CCS, particularly with respect to climate change policy in an international geopolitics context. The rationale for developing CCS should be the over-abundance of fossil fuel reserves (and resources in a climate change context. From a geopolitical point, it can be argued that the most important outcome from the successful commercialisation of CCS will be that fossil fuel-dependent economies with large fossil fuel resources will find it easier to comply with stringent greenhouse gas (GHG reduction targets (i.e. to attach a price to CO2 emissions. This should be of great importance since, from a geopolitical view, the curbing on GHG emissions cannot be isolated from security of supply and economic competition between regions. Thus, successful application of CCS may moderate geopolitical risks related to regional differences in the possibilities and thereby willingness to comply with large emission cuts. In Europe, application of CCS will enhance security of supply by fuel diversification from continued use of coal, especially domestic lignite. Introduction of CCS will also make possible negative emissions when using biomass as a fuel, i.e. in so called Biomass Energy CCS (BECCS. Yet, the development of BECCS relies on the successful development of fossil fuelled CCS since BECCS in itself is unlikely to be sufficient for establishing a cost efficient CCS infrastructure for transport and storage and because BECCS does not solve the problem with the abundant resources of fossil fuels. Results from research and development of capture, transport and storage of CO2 indicate that the barriers for commercialization of CCS should not be technical. Instead, the main barriers for implementation of CCS seem to be how to reach public acceptance

  19. Soil organic carbon storage and soil CO2 flux in the alpine meadow ecosystem

    Institute of Scientific and Technical Information of China (English)


    High-resolution sampling,measurements of organic carbon contents and 14C signatures of selected four soil profiles in the Haibei Station situated on the northeast Tibetan Plateau,and application of 14C tracing technology were conducted in an attempt to investigate the turnover times of soil organic car-bon and the soil-CO2 flux in the alpine meadow ecosystem. The results show that the organic carbon stored in the soils varies from 22.12×104 kg C hm-2 to 30.75×104 kg C hm-2 in the alpine meadow eco-systems,with an average of 26.86×104 kg C hm-2. Turnover times of organic carbon pools increase with depth from 45 a to 73 a in the surface soil horizon to hundreds of years or millennia or even longer at the deep soil horizons in the alpine meadow ecosystems. The soil-CO2 flux ranges from 103.24 g C m-2 a-1 to 254.93 gC m-2 a-1,with an average of 191.23 g C m-2 a-1. The CO2 efflux produced from microbial decomposition of organic matter varies from 73.3 g C m-2 a-1 to 181 g C m-2 a-1. More than 30% of total soil organic carbon resides in the active carbon pool and 72.8%―81.23% of total CO2 emitted from or-ganic matter decomposition results from the topsoil horizon (from 0 cm to 10 cm) for the Kobresia meadow. Responding to global warming,the storage,volume of flow and fate of the soil organic carbon in the alpine meadow ecosystem of the Tibetan Plateau will be changed,which needs further research.

  20. Integrated underground gas storage of CO2 and CH4 for renewable energy storage for a test case in China (United States)

    Kühn, Michael; Li, Qi; Nakaten, Natalie, Christine; Kempka, Thomas


    Integration and further development of the energy supply system in China is a major challenge for the years to come. Part of the strategy is the implementation of a low carbon energy system based on carbon dioxide capture and storage (CCS). The innovative idea presented here is based on an extension of the power-to-gas-to-power (PGP) technology by establishing a closed carbon dioxide cycle [1]. Thereto, hydrogen generated from excess renewable energy is transformed into methane for combustion in a combined cycle gas power plant. To comply with the fluctuating energy demand, carbon dioxide produced during methane combustion and required for the methanation process as well as excess methane are temporarily stored in two underground reservoirs located close to each other [2]. Consequently, renewable energy generation units can be operated even if energy demand is below consumption, while stored energy can be fed into the grid as energy demand exceeds production [3]. We studied a show case for Xinjiang in China [4] to determine the energy demand of the entire process chain based on numerical computer simulations for the operation of the CO2 and CH4 storage reservoirs, and to ascertain the pressure regimes present in the storage formations during the injection and production phases of the annual cycle. [1] Streibel M., Nakaten N., Kempka T., Kühn M. (2013) Analysis of an integrated carbon cycle for storage of renewables. Energy Procedia 40, 202-211. doi: 10.1016/j.egypro.2013.08.024. [2] Kühn M., Streibel M., Nakaten N.C., Kempka T. (2014) Integrated Underground Gas Storage of CO2 and CH4 to Decarbonise the "Power-to-gas-to-gas-to-power" Technology. Energy Procedia 59, 9-15. doi: 10.1016/j.egypro.2014.10.342 [3] Kühn M., Nakaten N.C., Streibel M., Kempka T. (2014) CO2 Geological Storage and Utilization for a Carbon Neutral "Power-to-gas-to-power" Cycle to Even Out Fluctuations of Renewable Energy Provision. Energy Procedia 63, 8044-8049. doi: 10.1016/j.egypro.2014

  1. Estimation of CO2 emissions from waste incinerators: Comparison of three methods. (United States)

    Lee, Hyeyoung; Yi, Seung-Muk; Holsen, Thomas M; Seo, Yong-Seok; Choi, Eunhwa


    Climate-relevant CO2 emissions from waste incineration were compared using three methods: making use of CO2 concentration data, converting O2 concentration and waste characteristic data, and using a mass balance method following Intergovernmental Panel on Climate Change (IPCC) guidelines. For the first two methods, CO2 and O2 concentrations were measured continuously from 24 to 86 days. The O2 conversion method in comparison to the direct CO2 measurement method had a 4.8% mean difference in daily CO2 emissions for four incinerators where analyzed waste composition data were available. However, the IPCC method had a higher difference of 13% relative to the direct CO2 measurement method. For three incinerators using designed values for waste composition, the O2 conversion and IPCC methods in comparison to the direct CO2 measurement method had mean differences of 7.5% and 89%, respectively. Therefore, the use of O2 concentration data measured for monitoring air pollutant emissions is an effective method for estimating CO2 emissions resulting from waste incineration. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Rehmer, Donald E.

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

  3. Numerical Modeling Studies of The Dissolution-Diffusion-Convection ProcessDuring CO2 Storage in Saline Aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, Karsten; Zhang, Keni


    For purposes of geologic storage, CO2 would be injected into saline formations at supercritical temperature and pressure conditions, and would form a separate phase that is immiscible with the aqueous phase (brine). At typical subsurface temperature and pressure conditions, supercritical CO2 (scCO2) has lower density than the aqueous phase and would experience an upward buoyancy force. Accordingly, the CO2 is expected to accumulate beneath the caprock at the top of the permeable interval, and could escape from the storage formation wherever (sub-)vertical pathways are available, such as fractures or faults through the caprock, or improperly abandoned wells. Over time, an increasing fraction of CO2 may dissolve in the aqueous phase, and eventually some of the aqueous CO2 may react with rock minerals to form poorly soluble carbonates. Dissolution into the aqueous phase and eventual sequestration as carbonates are highly desirable processes as they would increase permanence and security of storage. Dissolution of CO2 will establish phase equilibrium locally between the overlying CO2 plume and the aqueous phase beneath. If the aqueous phase were immobile, CO2 dissolution would be limited by the rate at which molecular diffusion can remove dissolved CO2 from the interface between CO2-rich and aqueous phases. This is a slow process. However, dissolution of CO2 is accompanied by a small increase in the density of the aqueous phase, creating a negative buoyancy force that can give rise to downward convection of CO2-rich brine, which in turn can greatly accelerate CO2 dissolution. This study explores the process of dissolution-diffusion-convection (DDC), using high-resolution numerical simulation. We find that geometric features of convection patterns are very sensitive to small changes in problem specifications, reflecting self-enhancing feedbacks and the chaotic nature of the process. Total CO2 dissolution rates on the other hand are found to be quite robust against

  4. Results from twelve years of continuous monitoring of the soil CO2 flux at the Ketzin CO2 storage pilot site, Germany (United States)

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


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

  5. The global carbon nation: Status of CO2 capture, storage and utilization (United States)

    Kocs, Elizabeth A.


    As the world transitions toward cleaner and more sustainable energy generation, Carbon Capture and Sequestration/Storage (CCS) plays an essential role in the portfolio of technologies to help reduce global greenhouse gas (GHG) emissions. The projected increase in population size and its resulting increase in global energy consumption, for both transportation and the electricity grid —the largest emitters of greenhouse gases, will continue to add to current CO2 emissions levels during this transition. Since eighty percent of today's global energy continues to be generated by fossil fuels, a shift to low-carbon energy sources will take many decades. In recent years, shifting to renewables and increasing energy efficiencies have taken more importance than deploying CCS. Together, this triad —renewables, energy efficiency, and CCS— represent a strong paradigm for achieving a carbon-free world. Additionally, the need to accelerate CCS in developing economies like China and India are of increasing concern since migration to renewables is unlikely to occur quickly in those countries. CCS of stationary sources, accounting for only 20% reduction in emissions, as well as increasing efficiency in current systems are needed for major reductions in emissions. A rising urgency for fifty to eighty percent reduction of CO2 emissions by 2050 and one hundred percent reduction by 2100 makes CCS all that more critical in the transition to a cleaner-energy future globally.

  6. Ground gas monitoring: implications for hydraulic fracturing and CO2 storage. (United States)

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


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

  7. Popcorn-Derived Porous Carbon for Energy Storage and CO2 Capture. (United States)

    Liang, Ting; Chen, Chunlin; Li, Xing; Zhang, Jian


    Porous carbon materials have drawn tremendous attention due to its applications in energy storage, gas/water purification, catalyst support, and other important fields. However, producing high-performance carbons via a facile and efficient route is still a big challenge. Here we report the synthesis of microporous carbon materials by employing a steam-explosion method with subsequent potassium activation and carbonization of the obtained popcorn. The obtained carbon features a large specific surface area, high porosity, and doped nitrogen atoms. Using as an electrode material in supercapacitor, it displays a high specific capacitance of 245 F g(-1) at 0.5 A g(-1) and a remarkable stability of 97.8% retention after 5000 cycles at 5 A g(-1). The product also exhibits a high CO2 adsorption capacity of 4.60 mmol g(-1) under 1066 mbar and 25 °C. Both areal specific capacitance and specific CO2 uptake are directly proportional to the surface nitrogen content. This approach could thus enlighten the batch production of porous nitrogen-doped carbons for a wide range of energy and environmental applications.

  8. The global carbon nation: Status of CO2 capture, storage and utilization

    Directory of Open Access Journals (Sweden)

    Kocs Elizabeth A.


    Full Text Available As the world transitions toward cleaner and more sustainable energy generation, Carbon Capture and Sequestration/Storage (CCS plays an essential role in the portfolio of technologies to help reduce global greenhouse gas (GHG emissions. The projected increase in population size and its resulting increase in global energy consumption, for both transportation and the electricity grid —the largest emitters of greenhouse gases, will continue to add to current CO2 emissions levels during this transition. Since eighty percent of today’s global energy continues to be generated by fossil fuels, a shift to low-carbon energy sources will take many decades. In recent years, shifting to renewables and increasing energy efficiencies have taken more importance than deploying CCS. Together, this triad —renewables, energy efficiency, and CCS— represent a strong paradigm for achieving a carbon-free world. Additionally, the need to accelerate CCS in developing economies like China and India are of increasing concern since migration to renewables is unlikely to occur quickly in those countries. CCS of stationary sources, accounting for only 20% reduction in emissions, as well as increasing efficiency in current systems are needed for major reductions in emissions. A rising urgency for fifty to eighty percent reduction of CO2 emissions by 2050 and one hundred percent reduction by 2100 makes CCS all that more critical in the transition to a cleaner-energy future globally.

  9. Using CO2 Prophet to estimate recovery factors for carbon dioxide enhanced oil recovery (United States)

    Attanasi, Emil D.


    -specific data that can be assembled and simplifying assumptions that allow assignment of default values for some reservoir parameters. These issues are discussed in the context of the CO2 Prophet EOR model, and their resolution is demonstrated with the computation of recovery-factor estimates for CO2-EOR of 143 reservoirs in the Powder River Basin Province in southeastern Montana and northeastern Wyoming.

  10. Environmental impact of an agro-waste based polygeneration without and with CO2 storage: Life cycle assessment approach. (United States)

    Jana, Kuntal; De, Sudipta


    Life cycle assessment (LCA) is the most scientific tool to measure environmental sustainability. Poly-generation is a better option than single-utility generation due to its higher resource utilization efficiency and more flexibility. Also biomass based polygeneration with CO2 capture and storage may be useful being 'net negative' greenhouse gas emission option. But this 'negativity' should be studied and confirmed through LCA. In this paper, cradle-to-gate life cycle assessment of a straw based polygeneration without and with CO2 storage is studied. Results show that captured CO2 of this polygeneration should be stored to get a net negative energy system. However, biomass distribution density, ethanol production rate and CO2 transportation distance affect the net GHG emission. For this polygeneration system, exergy based allocation should be preferred. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Armazenamento refrigerado de morango submetido a altas concentrações de CO2 Cold storage of strawberries under high CO2 concentrations

    Directory of Open Access Journals (Sweden)

    Luis C Cunha Junior


    strawberries. However, fruits and vegetables are not currently handled under cold chain in Brazil and, when it happens, it used to be at 10 to 15ºC. The goal of this work was to evaluate the quality and the shelf life of 'Oso Grande' strawberry at 10ºC associated to high carbon dioxide concentrations. Strawberries were randomized, chilled and stored at 10ºC in hermetic mini-chambers to apply the CO2 concentrations (0.03, 10, 20, 40 and 80% plus 20% O2. Strawberries were analyzed every two days while they were proper to consumption. The shelf life for strawberries at 20 and 40% CO2 was 8 days, while those at 0.03% CO2 lasted only two days. Strawberries at 80% CO2 maintained good appearance for 6 days, but they were considered unsuitable for consumption due to high levels of acetaldehyde (40.92 µg g-1 and ethanol (1,053 µg g-1 that gave evidence of fermentation process. The weight loss was less than 2% showing how efficient was the method used to control the relative humidity during the storage. Strawberries at 0.03 and 80% CO2 levels showed higher firmness loss. Those fruits lost 40% of the initial firmness. Strawberries at 20 and 40% CO2 lost only 28% of initial firmness. Despite of the statistical effect of the treatments in the external color it was not visually perceptible. Strawberries stored at 10ºC and 40% CO2 plus 20% O2 kept the marketable quality during 8 days.


    National Research Council Canada - National Science Library

    Carla Maria Abido Valentini; Mariano Martínez Espinosa; Sérgio Roberto de Paulo


    .... Considering that soil CO2 efflux is the greater component of the carboncycle of the biosphere, this work found an equation for estimating the soil CO2 efflux of an area of the Transition Forest...

  13. Earthquakes induced by fluid injection: Implications for secure CO2 storage (United States)

    Verdon, J.; Kendall, J. M.


    It is well understood that the injection of fluids into the subsurface can trigger seismic activity. Recently, the US unconventional gas boom has lead to an increase in the volumes of produced water being disposed in geological formations and a concomitant increase in triggered seismic events. This issue is especially pertinent for geologic carbon sequestration, where the injection volumes necessary to store the CO2 emissions from a typical coal-fired power station far exceed the volumes known to have triggered seismic activity. Moreover, unlike water disposal operations, where there is no strong buoyancy drive to return injected fluids to the surface, CO2 sequestration requires a sealing caprock to prevent upward CO2 migration. Induced seismic events may create or reactivate faults and fracture networks, compromising the hydraulic integrity of the caprock. Therefore, induced seismic activity at future CCS sites is of doubly significant, given both the direct seismic hazard and the risk to secure CO2 storage. With this in mind, we re-examine case histories of seismic activity induced by waste water disposal into sedimentary formations with the intention of learning lessons that can be applied to future CCS sites. In particular, we examine the spatial and temporal distributions of events to determine whether there are any rules-of-thumb that might be usefully applied when appraising and monitoring operations. We find that in all cases, at least some seismicity occurs at the depth of the injection interval, but the majority (~80% of events) occur at least 500m below the injection depth. Less than 2% of events occur more than 500m above the shallowest injection interval. This observation must be considered encouraging from a CCS perspective, where seismicity in sealing caprocks will be of greatest concern. However, without a phenomenological explanation for the relative lack of seismicity above injection depths, it cannot be guaranteed that such observations would be

  14. Spatial and Temporal Monitoring Resolutions for CO2 Leakage Detection at Carbon Storage Sites (United States)

    Yang, Y. M.; Dilmore, R. M.; Daley, T. M.; Carroll, S.; Mansoor, K.; Gasperikova, E.; Harbert, W.; Wang, Z.; Bromhal, G. S.; Small, M.


    Different leakage monitoring techniques offer different strengths in detection sensitivity, coverage, feedback time, cost, and technology availability, such that they may complement each other when applied together. This research focuses on quantifying the spatial coverage and temporal resolution of detection response for several geophysical remote monitoring and direct groundwater monitoring techniques for an optimal monitoring plan for CO2 leakage detection. Various monitoring techniques with different monitoring depths are selected: 3D time-lapse seismic survey, wellbore pressure, groundwater chemistry and soil gas. The spatial resolution in terms of leakage detectability is quantified through the effective detection distance between two adjacent monitors, given the magnitude of leakage and specified detection probability. The effective detection distances are obtained either from leakage simulations with various monitoring densities or from information garnered from field test data. These spatial leakage detection resolutions are affected by physically feasible monitoring design and detection limits. Similarly, the temporal resolution, in terms of leakage detectability, is quantified through the effective time to positive detection of a given size of leak and a specified detection probability, again obtained either from representative leakage simulations with various monitoring densities or from field test data. The effective time to positive detection is also affected by operational feedback time (associated with sampling, sample analysis and data interpretation), with values obtained mainly through expert interviews and literature review. In additional to the spatial and temporal resolutions of these monitoring techniques, the impact of CO2 plume migration speed and leakage detection sensitivity of each monitoring technique are also discussed with consideration of how much monitoring is necessary for effective leakage detection and how these monitoring

  15. Geometry-coupled reactive fluid transport at the fracture scale -Application to CO 2 geologic storage

    KAUST Repository

    Kim, Seunghee


    Water acidification follows CO2 injection and leads to reactive fluid transport through pores and rock fractures, with potential implications to reservoirs and wells in CO2 geologic storage and enhanced oil recovery. Kinetic rate laws for dissolution reactions in calcite and anorthite are combined with Navier-Stokes law and advection-diffusion transport to perform geometry-coupled numerical simulations in order to study the evolution of chemical reactions, species concentration and fracture morphology. Results are summarized as a function of two dimensionless parameters: the Damköhler number Da which is the ratio between advection and reaction times, and the transverse Peclet number Pe defined as the ratio between the time for diffusion across the fracture and the time for advection along the fracture. Reactant species are readily consumed near the inlet in a carbonate reservoir when the flow velocity is low (low transverse Peclet number and Da>10-1). At high flow velocities, diffusion fails to homogenize the concentration field across the fracture (high transverse Peclet number Pe>10-1). When the reaction rate is low as in anorthite reservoirs (Da<10-1) reactant species are more readily transported towards the outlet. At a given Peclet number, a lower Damköhler number causes the flow channel to experience a more uniform aperture enlargement along the length of the fracture. When the length-to-aperture ratio is sufficiently large, say l/d>30, the system response resembles the solution for 1-D reactive fluid transport. A decreased length-to-aperture ratio slows the diffusive transport of reactant species to the mineral fracture surface, and analyses of fracture networks must take into consideration both the length and slenderness of individual fractures in addition to Pe and Da numbers.

  16. Estimating surface CO2 fluxes from space-borne CO2 dry air mole fraction observations using an ensemble Kalman Filter

    Directory of Open Access Journals (Sweden)

    S. Dance


    Full Text Available We have developed an ensemble Kalman Filter (EnKF to estimate 8-day regional surface fluxes of CO2 from space-borne CO2 dry-air mole fraction observations (XCO2 and evaluate the approach using a series of synthetic experiments, in preparation for data from the NASA Orbiting Carbon Observatory (OCO. The 32-day duty cycle of OCO alternates every 16 days between nadir and glint measurements of backscattered solar radiation at short-wave infrared wavelengths. The EnKF uses an ensemble of states to represent the error covariances to estimate 8-day CO2 surface fluxes over 144 geographical regions. We use a 12×8-day lag window, recognising that XCO2 measurements include surface flux information from prior time windows. The observation operator that relates surface CO2 fluxes to atmospheric distributions of XCO2 includes: a the GEOS-Chem transport model that relates surface fluxes to global 3-D distributions of CO2 concentrations, which are sampled at the time and location of OCO measurements that are cloud-free and have aerosol optical depths 2 profiles to XCO2, accounting for differences between nadir and glint measurements, and the associated scene-dependent observation errors. We show that OCO XCO2 measurements significantly reduce the uncertainties of surface CO2 flux estimates. Glint measurements are generally better at constraining ocean CO2 flux estimates. Nadir XCO2 measurements over the terrestrial tropics are sparse throughout the year because of either clouds or smoke. Glint measurements provide the most effective constraint for estimating tropical terrestrial CO2 fluxes by accurately sampling fresh continental outflow over neighbouring oceans. We also present results from sensitivity experiments that investigate how flux estimates change with 1 bias and unbiased errors, 2 alternative duty cycles, 3 measurement density and correlations, 4 the spatial resolution of estimated flux estimates, and 5 reducing the length of the lag window and the

  17. CO2 storage resources, reserves, and reserve growth: Toward a methodology for integrated assessment of the storage capacity of oil and gas reservoirs and saline formations (United States)

    Burruss, Robert


    Geologically based methodologies to assess the possible volumes of subsurface CO2 storage must apply clear and uniform definitions of resource and reserve concepts to each assessment unit (AU). Application of the current state of knowledge of geologic, hydrologic, geochemical, and geophysical parameters (contingencies) that control storage volume and injectivity allows definition of the contingent resource (CR) of storage. The parameters known with the greatest certainty are based on observations on known traps (KTs) within the AU that produced oil, gas, and water. The aggregate volume of KTs within an AU defines the most conservation volume of contingent resource. Application of the concept of reserve growth to CR volume provides a logical path for subsequent reevaluation of the total resource as knowledge of CO2 storage processes increases during implementation of storage projects. Increased knowledge of storage performance over time will probably allow the volume of the contingent resource of storage to grow over time, although negative growth is possible.

  18. Observed CO2-induced reactivity in werkendam gas field, the Dutch storage analogue

    NARCIS (Netherlands)

    Koenen, M.; Wasch, L.; Waldmann, S.; Gijp, S. van der


    Natural CO2 fields provide important insights in the long-term geochemical behaviour of CO2 in a reservoir and the potential of permanent trapping in carbonate minerals. The Werkendam gas field in The Netherlands, discovered during gas exploration activities in 1991, contains >70% CO2. Core samples

  19. An ensemble data assimilation system to estimate CO2 surface fluxes from atmospheric trace gas observations

    NARCIS (Netherlands)

    Peters, W.; Miller, J.B.; Whitaker, J.; Denning, A.S.; Hirsch, A.; Krol, M.C.; Zupanski, D.; Bruhwiler, L.; Tans, P.P.


    We present a data assimilation system to estimate surface fluxes of CO2 and other trace gases from observations of their atmospheric abundances. The system is based on ensemble data assimilation methods under development for Numerical Weather Prediction (NWP) and is the first of its kind to be used

  20. Stable large-scale CO2 storage in defiance of an energy system based on renewable energy - Modelling the impact of varying CO2 injection rates on reservoir behavior (United States)

    Bannach, Andreas; Hauer, Rene; Martin, Streibel; Stienstra, Gerard; Kühn, Michael


    The IPCC Report 2014 strengthens the need for CO2 storage as part of CCS or BECCS to reach ambitious climate goals despite growing energy demand in the future. The further expansion of renewable energy sources is a second major pillar. As it is today in Germany the weather becomes the controlling factor for electricity production by fossil fuelled power plants which lead to significant fluctuations of CO2-emissions which can be traced in injection rates if the CO2 were captured and stored. To analyse the impact of such changing injection rates on a CO2 storage reservoir. two reservoir simulation models are applied: a. An (smaller) reservoir model approved by gas storage activities for decades, to investigate the dynamic effects in the early stage of storage filling (initial aquifer displacement). b. An anticline structure big enough to accommodate a total amount of ≥ 100 Mega tons CO2 to investigate the dynamic effects for the entire operational life time of the storage under particular consideration of very high filling levels (highest aquifer compression). Therefore a reservoir model was generated. The defined yearly injection rate schedule is based on a study performed on behalf of IZ Klima (DNV GL, 2014). According to this study the exclusive consideration of a pool of coal-fired power plants causes the most intensive dynamically changing CO2 emissions and hence accounts for variations of a system which includes industry driven CO2 production. Besides short-term changes (daily & weekly cycles) seasonal influences are also taken into account. Simulation runs cover a variation of injection points (well locations at the top vs. locations at the flank of the structure) and some other largely unknown reservoir parameters as aquifer size and aquifer mobility. Simulation of a 20 year storage operation is followed by a post-operational shut-in phase which covers approximately 500 years to assess possible effects of changing injection rates on the long-term reservoir

  1. A method for examining the geospatial distribution of CO2 storage resources applied to the Pre-Punta Gorda Composite and Dollar Bay reservoirs of the South Florida Basin, U.S.A (United States)

    Roberts-Ashby, Tina; Brandon N. Ashby,


    This paper demonstrates geospatial modification of the USGS methodology for assessing geologic CO2 storage resources, and was applied to the Pre-Punta Gorda Composite and Dollar Bay reservoirs of the South Florida Basin. The study provides detailed evaluation of porous intervals within these reservoirs and utilizes GIS to evaluate the potential spatial distribution of reservoir parameters and volume of CO2 that can be stored. This study also shows that incorporating spatial variation of parameters using detailed and robust datasets may improve estimates of storage resources when compared to applying uniform values across the study area derived from small datasets, like many assessment methodologies. Geospatially derived estimates of storage resources presented here (Pre-Punta Gorda Composite = 105,570 MtCO2; Dollar Bay = 24,760 MtCO2) were greater than previous assessments, which was largely attributed to the fact that detailed evaluation of these reservoirs resulted in higher estimates of porosity and net-porous thickness, and areas of high porosity and thick net-porous intervals were incorporated into the model, likely increasing the calculated volume of storage space available for CO2 sequestration. The geospatial method for evaluating CO2 storage resources also provides the ability to identify areas that potentially contain higher volumes of storage resources, as well as areas that might be less favorable.

  2. On-board co2 capture and storage with metal organic framework

    KAUST Repository

    Eddaoudi, Mohamed


    In general, this disclosure describes method of capturing and storing CO2 on a vehicle. The method includes contacting an vehicle exhaust gas with one or more of a first metal organic framework (MOF) composition sufficient to separate CO2 from the exhaust gas, contacting the separated CO2 with one or more of a second MOF composition sufficient to store the CO2 and wherein the one or more first MOF composition comprises one or more SIFSIX-n-M MOF and wherein M is a metal and n is 2 or 3. Embodiments also describe an apparatus or system for capturing and storing CO2 onboard a vehicle.

  3. Reduction of CO2 Emissions Due to Wind Energy - Methods and Issues in Estimating Operational Emission Reductions

    Energy Technology Data Exchange (ETDEWEB)

    Holttinen, Hannele; Kiviluoma, Juha; McCann, John; Clancy, Matthew; Millgan, Michael; Pineda, Ivan; Eriksen, Peter Borre; Orths, Antje; Wolfgang, Ove


    This paper presents ways of estimating CO2 reductions of wind power using different methodologies. Estimates based on historical data have more pitfalls in methodology than estimates based on dispatch simulations. Taking into account exchange of electricity with neighboring regions is challenging for all methods. Results for CO2 emission reductions are shown from several countries. Wind power will reduce emissions for about 0.3-0.4 MtCO2/MWh when replacing mainly gas and up to 0.7 MtCO2/MWh when replacing mainly coal powered generation. The paper focuses on CO2 emissions from power system operation phase, but long term impacts are shortly discussed.

  4. A simple approach for the estimation of CO2 penetration depth into a caprock layer

    Directory of Open Access Journals (Sweden)

    J.G. Wang


    Full Text Available Caprock is a water-saturated formation with a sufficient entry capillary pressure to prevent the upward migration of a buoyant fluid. When the entry capillary pressure of caprock is smaller than the pressure exerted by the buoyant CO2 plume, CO2 gradually penetrates into the caprock. The CO2 penetration depth into a caprock layer can be used to measure the caprock sealing efficiency and becomes the key issue to the assessment of caprock sealing efficiency. On the other hand, our numerical simulations on a caprock layer have revealed that a square root law for time and pore pressure exists for the CO2 penetration into the caprock layer. Based on this finding, this study proposes a simple approach to estimate the CO2 penetration depth into a caprock layer. This simple approach is initially developed to consider the speed of CO2 invading front. It explicitly expresses the penetration depth with pressuring time, pressure difference and pressure magnitude. This simple approach is then used to fit three sets of experimental data and good fittings are observed regardless of pressures, strengths of porous media, and pore fluids (water, hydrochloric acid, and carbonic acid. Finally, theoretical analyses are conducted to explore those factors affecting CO2 penetration depth. The effects of capillary pressure, gas sorption induced swelling, and fluid property are then included in this simple approach. These results show that this simple approach can predict the penetration depth into a caprock layer with sufficient accuracy, even if complicated interactions in penetration process are not explicitly expressed in this simple formula.

  5. On the potential for CO2 mineral storage in continental flood basalts - PHREEQC batch- and 1D diffusion-reaction simulations. (United States)

    Van Pham, Thi Hai; Aagaard, Per; Hellevang, Helge


    Continental flood basalts (CFB) are considered as potential CO2 storage sites because of their high reactivity and abundant divalent metal ions that can potentially trap carbon for geological timescales. Moreover, laterally extensive CFB are found in many place in the world within reasonable distances from major CO2 point emission sources.Based on the mineral and glass composition of the Columbia River Basalt (CRB) we estimated the potential of CFB to store CO2 in secondary carbonates. We simulated the system using kinetic dependent dissolution of primary basalt-minerals (pyroxene, feldspar and glass) and the local equilibrium assumption for secondary phases (weathering products). The simulations were divided into closed-system batch simulations at a constant CO2 pressure of 100 bar with sensitivity studies of temperature and reactive surface area, an evaluation of the reactivity of H2O in scCO2, and finally 1D reactive diffusion simulations giving reactivity at CO2 pressures varying from 0 to 100 bar.Although the uncertainty in reactive surface area and corresponding reaction rates are large, we have estimated the potential for CO2 mineral storage and identified factors that control the maximum extent of carbonation. The simulations showed that formation of carbonates from basalt at 40 C may be limited to the formation of siderite and possibly FeMg carbonates. Calcium was largely consumed by zeolite and oxide instead of forming carbonates. At higher temperatures (60 - 100 C), magnesite is suggested to form together with siderite and ankerite. The maximum potential of CO2 stored as solid carbonates, if CO2 is supplied to the reactions unlimited, is shown to depend on the availability of pore space as the hydration and carbonation reactions increase the solid volume and clog the pore space. For systems such as in the scCO2 phase with limited amount of water, the total carbonation potential is limited by the amount of water present for hydration of basalt.

  6. On the potential for CO2 mineral storage in continental flood basalts – PHREEQC batch- and 1D diffusion–reaction simulations

    Directory of Open Access Journals (Sweden)

    Van Pham Thi


    Full Text Available Abstract Continental flood basalts (CFB are considered as potential CO2 storage sites because of their high reactivity and abundant divalent metal ions that can potentially trap carbon for geological timescales. Moreover, laterally extensive CFB are found in many place in the world within reasonable distances from major CO2 point emission sources. Based on the mineral and glass composition of the Columbia River Basalt (CRB we estimated the potential of CFB to store CO2 in secondary carbonates. We simulated the system using kinetic dependent dissolution of primary basalt-minerals (pyroxene, feldspar and glass and the local equilibrium assumption for secondary phases (weathering products. The simulations were divided into closed-system batch simulations at a constant CO2 pressure of 100 bar with sensitivity studies of temperature and reactive surface area, an evaluation of the reactivity of H2O in scCO2, and finally 1D reactive diffusion simulations giving reactivity at CO2 pressures varying from 0 to 100 bar. Although the uncertainty in reactive surface area and corresponding reaction rates are large, we have estimated the potential for CO2 mineral storage and identified factors that control the maximum extent of carbonation. The simulations showed that formation of carbonates from basalt at 40 C may be limited to the formation of siderite and possibly FeMg carbonates. Calcium was largely consumed by zeolite and oxide instead of forming carbonates. At higher temperatures (60 – 100 C, magnesite is suggested to form together with siderite and ankerite. The maximum potential of CO2 stored as solid carbonates, if CO2 is supplied to the reactions unlimited, is shown to depend on the availability of pore space as the hydration and carbonation reactions increase the solid volume and clog the pore space. For systems such as in the scCO2 phase with limited amount of water, the total carbonation potential is limited by the amount of water present

  7. On the potential for CO2 mineral storage in continental flood basalts – PHREEQC batch- and 1D diffusion–reaction simulations (United States)


    Continental flood basalts (CFB) are considered as potential CO2 storage sites because of their high reactivity and abundant divalent metal ions that can potentially trap carbon for geological timescales. Moreover, laterally extensive CFB are found in many place in the world within reasonable distances from major CO2 point emission sources. Based on the mineral and glass composition of the Columbia River Basalt (CRB) we estimated the potential of CFB to store CO2 in secondary carbonates. We simulated the system using kinetic dependent dissolution of primary basalt-minerals (pyroxene, feldspar and glass) and the local equilibrium assumption for secondary phases (weathering products). The simulations were divided into closed-system batch simulations at a constant CO2 pressure of 100 bar with sensitivity studies of temperature and reactive surface area, an evaluation of the reactivity of H2O in scCO2, and finally 1D reactive diffusion simulations giving reactivity at CO2 pressures varying from 0 to 100 bar. Although the uncertainty in reactive surface area and corresponding reaction rates are large, we have estimated the potential for CO2 mineral storage and identified factors that control the maximum extent of carbonation. The simulations showed that formation of carbonates from basalt at 40 C may be limited to the formation of siderite and possibly FeMg carbonates. Calcium was largely consumed by zeolite and oxide instead of forming carbonates. At higher temperatures (60 – 100 C), magnesite is suggested to form together with siderite and ankerite. The maximum potential of CO2 stored as solid carbonates, if CO2 is supplied to the reactions unlimited, is shown to depend on the availability of pore space as the hydration and carbonation reactions increase the solid volume and clog the pore space. For systems such as in the scCO2 phase with limited amount of water, the total carbonation potential is limited by the amount of water present for hydration of basalt

  8. Basin-Scale Hydrologic Impacts of CO2 Storage: Regulatory and Capacity Implications

    Energy Technology Data Exchange (ETDEWEB)

    Birkholzer, J.T.; Zhou, Q.


    Industrial-scale injection of CO{sub 2} into saline sedimentary basins will cause large-scale fluid pressurization and migration of native brines, which may affect valuable groundwater resources overlying the deep sequestration reservoirs. In this paper, we discuss how such basin-scale hydrologic impacts can (1) affect regulation of CO{sub 2} storage projects and (2) may reduce current storage capacity estimates. Our assessment arises from a hypothetical future carbon sequestration scenario in the Illinois Basin, which involves twenty individual CO{sub 2} storage projects in a core injection area suitable for long-term storage. Each project is assumed to inject five million tonnes of CO{sub 2} per year for 50 years. A regional-scale three-dimensional simulation model was developed for the Illinois Basin that captures both the local-scale CO{sub 2}-brine flow processes and the large-scale groundwater flow patterns in response to CO{sub 2} storage. The far-field pressure buildup predicted for this selected sequestration scenario suggests that (1) the area that needs to be characterized in a permitting process may comprise a very large region within the basin if reservoir pressurization is considered, and (2) permits cannot be granted on a single-site basis alone because the near- and far-field hydrologic response may be affected by interference between individual sites. Our results also support recent studies in that environmental concerns related to near-field and far-field pressure buildup may be a limiting factor on CO{sub 2} storage capacity. In other words, estimates of storage capacity, if solely based on the effective pore volume available for safe trapping of CO{sub 2}, may have to be revised based on assessments of pressure perturbations and their potential impact on caprock integrity and groundwater resources, respectively. We finally discuss some of the challenges in making reliable predictions of large-scale hydrologic impacts related to CO{sub 2

  9. Energy Optimization for Transcritical CO2 Heat Pump for Combined Heating and Cooling and Thermal Storage Applications

    DEFF Research Database (Denmark)

    Do Carmo, Carolina Madeira Ramos; Blarke, Morten; Yazawa, Kazuaki


    and cold thermal storages know as Thermal Battery (TB) (Blarke, 2012). Smart and effective use of intermittent renewable energy resources (for example solar and wind power) is obtained supplying water heating (>70 oC) and cooling services (...A transcritical heat pump (THP) cycle using carbon dioxide (CO2) as the refrigerant is known to feature an excellent coefficient of performance (COP) as a thermodynamic system. Using this feature, we are designing and building a system that combines a water-to-water CO2 heat pump with both hot...... hypothesis is that if electricity generated by intermittent sources is destined for thermal end-uses an efficient conversion of electricity to thermal energy and storage enables a flexible power supply. Thermal storage is more cost-effective than any electro-chemical or mechanical storage technology...

  10. Performance Estimation of Supercritical Co2 Micro Modular Reactor (MMR) for Varying Cooling Air Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Yoonhan; Kim, Seong Gu; Cho, Seong Kuk; Lee, Jeong Ik [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)


    A Small Modular Reactor (SMR) receives interests for the various application such as electricity co-generation, small-scale power generation, seawater desalination, district heating and propulsion. As a part of SMR development, supercritical CO2 Micro Modular Reactor (MMR) of 36.2MWth in power is under development by the KAIST research team. To enhance the mobility, the entire system including the power conversion system is designed for the full modularization. Based on the preliminary design, the thermal efficiency is 31.5% when CO2 is sufficiently cooled to the design temperature. A supercritical CO2 MMR is designed to supply electricity to the remote regions. The ambient temperature of the area can influence the compressor inlet temperature as the reactor is cooled with the atmospheric air. To estimate the S-CO2 cycle performance for various environmental conditions, A quasi-static analysis code is developed. For the off design performance of S-CO2 turbomachineries, the experimental result of Sandia National Lab (SNL) is utilized.

  11. Point-source CO2 emission estimation from airborne sampled CO2 mass density: a case study for an industrial plant in Biganos, Southern France. (United States)

    Carotenuto, Federico; Gioli, Beniamino; Toscano, Piero; Zaldei, Alessandro; Miglietta, Franco


    One interesting aspect in the airborne sampling of ground emissions of all types (from CO2 to particulate matter) is the ability to understand the source from which these emissions originated and, therefore, obtain an estimation of that ground source's strength. Recently an aerial campaign has been conducted in order to sample emissions coming from a paper production plant in Biganos (France). The campaign made use of a Sky Arrow ERA (Environmental Research Aircraft) equipped with a mobile flux platform system. This latter system couples (among the various instrumentation) a turbulence probe (BAT) and a LICOR 7500 open-path infra-red gas analyzer that also enables the estimation of high-resolution fluxes of different scalars via the spatial-integrated eddy-covariance technique. Aircraft data showed a marked increase in CO2 mass density downwind the industrial area, while vertical profiles samplings showed that concentrations were changing with altitude. The estimation of the CO2 source was obtained using a simple mass balance approach, that is, by integrating the product of CO2 concentration and the mass flow rate through a cross-sectional area downwind of the point source. The results were compared with those obtained by means of a "forward-mode" Lagrangian dispersion model operated iteratively. CO2 source strength were varied at each iteration to obtain an optimal convergence between the modeled atmospheric concentrations and the concentration data observed by the aircraft. The procedure makes use of wind speed and atmospheric turbulence data which are directly measured by the BAT probe at different altitudes. The two methods provided comparable estimates of the CO2 source thus providing a substantial validation of the model-based iterative dispersion procedure. We consider that this data-model integration approach involving aircraft surveys and models may substantially enhance the estimation of point and area sources of any scalar, even in more complex

  12. Feasibility of Monitoring the Hontomín (Burgos, Spain) CO2 Storage Site Using a Deep EM Source (United States)

    Vilamajó, Eloi; Queralt, Pilar; Ledo, Juanjo; Marcuello, Alex


    Geophysical methods have been used experimentally during the last decade, a period of strong development, being adopted as complementary techniques for characterizing and monitoring hydrocarbon and gas reservoirs. In this study, we evaluated the ability of the controlled source electromagnetic (CSEM) method to monitor the storage of CO2 at the Research Laboratory on Geological Storage of CO2 at Hontomín (Burgos, Spain). Two aspects of the CSEM monitoring were examined considering the geoelectrical structure at the site, the technological constraints and the noise conditions of the Hontomín area. Borehole-to-surface simulations were performed to evaluate the detectability of the resistivity changes in the reservoir and the capacity to determine the location of the CO2 plume. The synthetic time-lapse study explores the possibilities of CSEM monitoring with a deep electric source. Three depths of the source are analyzed: above the plume, inside the plume, and beneath the stored CO2. In terms of the Hontomín storage site, the study confirmed that a deep electric source located beneath the injection depth can provide valuable information on the behavior of the stored CO2.

  13. Δ14CO2from dark respiration in plants and its impact on the estimation of atmospheric fossil fuel CO2. (United States)

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


    Radiocarbon ( 14 C) has been widely used for quantification of fossil fuel CO 2 (CO 2ff ) in the atmosphere and for ecosystem source partitioning studies. The strength of the technique lies in the intrinsic differences between the 14 C signature of fossil fuels and other sources. In past studies, the 14 C content of CO 2 derived from plants has been equated with the 14 C content of the atmosphere. Carbon isotopic fractionation mechanisms vary among plants however, and experimental study on fractionation associated with dark respiration is lacking. Here we present accelerator mass spectrometry (AMS) radiocarbon results of CO 2 respired from 21 plants using a lab-incubation method and associated bulk organic matter. From the respired CO 2 we determine Δ 14 C res values, and from the bulk organic matter we determine Δ 14 C bom values. A significant difference between Δ 14 C res and Δ 14 C bom (P < 0.01) was observed for all investigated plants, ranging from -42.3‰ to 10.1‰. The results show that Δ 14 C res values are in agreement with mean atmospheric Δ 14 CO 2 for several days leading up to the sampling date, but are significantly different from corresponding bulk organic Δ 14 C values. We find that although dark respiration is unlikely to significantly influence the estimation of CO 2ff , an additional bias associated with the respiration rate during a plant's growth period should be considered when using Δ 14 C in plants to quantify atmospheric CO 2ff . Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. CO2 abatement in the iron and steel industry - the case for carbon capture and storage (CCS

    Directory of Open Access Journals (Sweden)

    A.V. Todorut


    Full Text Available The steel industry is amongst the most energy-intensive industries also consuming large amounts of coal and emitting significant volumes of carbon dioxide (CO2. Studies indicate that steelmaking accounts for 6 - 7 % of world anthropogenic CO2 emissions, and 27 % of the total emissions of the world’s manufacturing sector. Steel manufacturers have responded to sustainable resource use and development adopting several measures attaining a reduction in energy consumption of 60 % in the last 50 years. The paper discusses Carbon Capture and Storage (CCS as a CO2 mitigation option, after the 2015 Paris Climate Conference (COP 21 and in relation to the European Regulation for CO2 measurement, reporting and verification.

  15. Comparison of Sea-Air CO2 Flux Estimates Using Satellite-Based Versus Mooring Wind Speed Data (United States)

    Sutton, A. J.; Sabine, C. L.; Feely, R. A.; Wanninkhof, R. H.


    The global ocean is a major sink of anthropogenic CO2, absorbing approximately 27% of CO2 emissions since the beginning of the industrial revolution. Any variation or change in the ocean CO2 sink has implications for future climate. Observations of sea-air CO2 flux have relied primarily on ship-based underway measurements of partial pressure of CO2 (pCO2) combined with satellite, model, or multi-platform wind products. Direct measurements of ΔpCO2 (seawater - air pCO2) and wind speed from moored platforms now allow for high-resolution CO2 flux time series. Here we present a comparison of CO2 flux calculated from moored ΔpCO2 measured on four moorings in different biomes of the Pacific Ocean in combination with: 1) Cross-Calibrated Multi-Platform (CCMP) winds or 2) wind speed measurements made on ocean reference moorings excluded from the CCMP dataset. Preliminary results show using CCMP winds overestimates CO2 flux on average by 5% at the Kuroshio Extension Observatory, Ocean Station Papa, WHOI Hawaii Ocean Timeseries Station, and Stratus. In general, CO2 flux seasonality follows patterns of seawater pCO2 and SST with periods of CO2 outgassing during summer and CO2 uptake during winter at these locations. Any offsets or seasonal biases in CCMP winds could impact global ocean sink estimates using this data product. Here we present patterns and trends between the two CO2 flux estimates and discuss the potential implications for tracking variability and change in global ocean CO2 uptake.

  16. Impacts and effects of mesoscale ocean eddies on ocean carbon storage and atmospheric pCO2 (United States)

    Munday, D. R.; Johnson, H. L.; Marshall, D. P.


    An idealized numerical ocean model is used to investigate the sensitivity of the partial pressure of atmospheric carbon dioxide (pCO2) to changes in surface wind stress when mesoscale eddies are permitted in the flow. When wind stress increases, pCO_2 increases, and vice versa. The introduction of mesoscale eddies reduces the overall sensitivity of pCO2 by changing the sensitivity of ocean carbon storage due to the saturation state of carbon dioxide, the net air-sea disequilibrium, soft tissue carbon, and the carbonate pump. However, a full carbon pump decomposition shows different responses for different ocean carbon storage terms. For example, air-sea disequilibrium is actually more sensitive to increased winds at eddy-permitting resolution, whereas soft tissue carbon is much less sensitive to wind changes in an eddy-permitting ocean. Changes in pycnocline depth and the strength of both upper and lower cells of the meridional overturning circulation affect this sensitivity.

  17. Effects of elevated CO2 and trace ethylene present throughout the storage season on the processing colour of stored potatoes

    NARCIS (Netherlands)

    Daniels-Lake, B.J.


    Previous short-term trials (9-week duration) have shown that the fry colour of stored potatoes (Solanum tuberosum L.) can be negatively affected by simultaneous exposure to elevated CO2 plus a trace concentration of ethylene gas. In the present study, trials were conducted during each of two storage

  18. Characteristics of mechanical wellbore failure and damage: Insights of discrete element modelling and application to CO2 storage

    NARCIS (Netherlands)

    Heege, J.H. ter; Orlic, B.; Hoedeman, G.C.


    Wellbore zonal isolation is particularly important for subsurface storage of CO2, where well integrity must be ensured for very long time spans. In this study, three dimensional discrete element models of wellbore systems have been used to simulate failure and damage of wellbore cement and

  19. Physicochemical effects of discrete CO2-SO2 mixtures on injection and storage in a sandstone aquifer

    NARCIS (Netherlands)

    Waldmann, S.; Hofstee, C.; Koenen, M.; Loeve, D.


    Geological storage of captured CO2, which typically will contain certain amounts of impurities, in salineaquifers is of potential to reduce greenhouse gas emissions into the atmosphere. The co-injection of theimpurity SO2has an effect on the chemical reactivity of the fluid and solid phases as well

  20. CO2leakage from carbon dioxide capture and storage (CCS) systems affects organic matter cycling in surface marine sediments. (United States)

    Rastelli, Eugenio; Corinaldesi, Cinzia; Dell'Anno, Antonio; Amaro, Teresa; Greco, Silvestro; Lo Martire, Marco; Carugati, Laura; Queirós, Ana M; Widdicombe, Stephen; Danovaro, Roberto


    Carbon dioxide capture and storage (CCS), involving the injection of CO 2 into the sub-seabed, is being promoted worldwide as a feasible option for reducing the anthropogenic CO 2 emissions into the atmosphere. However, the effects on the marine ecosystems of potential CO 2 leakages originating from these storage sites have only recently received scientific attention, and little information is available on the possible impacts of the resulting CO 2 -enriched seawater plumes on the surrounding benthic ecosystem. In the present study, we conducted a 20-weeks mesocosm experiment exposing coastal sediments to CO 2 -enriched seawater (at 5000 or 20,000 ppm), to test the effects on the microbial enzymatic activities responsible for the decomposition and turnover of the sedimentary organic matter in surface sediments down to 15 cm depth. Our results indicate that the exposure to high-CO 2 concentrations reduced significantly the enzymatic activities in the top 5 cm of sediments, but had no effects on subsurface sediment horizons (from 5 to 15 cm depth). In the surface sediments, both 5000 and 20,000 ppm CO 2 treatments determined a progressive decrease over time in the protein degradation (up to 80%). Conversely, the degradation rates of carbohydrates and organic phosphorous remained unaltered in the first 2 weeks, but decreased significantly (up to 50%) in the longer term when exposed at 20,000 ppm of CO 2 . Such effects were associated with a significant change in the composition of the biopolymeric carbon (due to the accumulation of proteins over time in sediments exposed to high-pCO 2 treatments), and a significant decrease (∼20-50% at 5000 and 20,000 ppm respectively) in nitrogen regeneration. We conclude that in areas immediately surrounding an active and long-lasting leak of CO 2 from CCS reservoirs, organic matter cycling would be significantly impacted in the surface sediment layers. The evidence of negligible impacts on the deeper sediments should be

  1. Plant responses to increasing CO2 reduce estimates of climate impacts on drought severity. (United States)

    Swann, Abigail L S; Hoffman, Forrest M; Koven, Charles D; Randerson, James T


    Rising atmospheric CO2 will make Earth warmer, and many studies have inferred that this warming will cause droughts to become more widespread and severe. However, rising atmospheric CO2 also modifies stomatal conductance and plant water use, processes that are often are overlooked in impact analysis. We find that plant physiological responses to CO2 reduce predictions of future drought stress, and that this reduction is captured by using plant-centric rather than atmosphere-centric metrics from Earth system models (ESMs). The atmosphere-centric Palmer Drought Severity Index predicts future increases in drought stress for more than 70% of global land area. This area drops to 37% with the use of precipitation minus evapotranspiration (P-E), a measure that represents the water flux available to downstream ecosystems and humans. The two metrics yield consistent estimates of increasing stress in regions where precipitation decreases are more robust (southern North America, northeastern South America, and southern Europe). The metrics produce diverging estimates elsewhere, with P-E predicting decreasing stress across temperate Asia and central Africa. The differing sensitivity of drought metrics to radiative and physiological aspects of increasing CO2 partly explains the divergent estimates of future drought reported in recent studies. Further, use of ESM output in offline models may double-count plant feedbacks on relative humidity and other surface variables, leading to overestimates of future stress. The use of drought metrics that account for the response of plant transpiration to changing CO2, including direct use of P-E and soil moisture from ESMs, is needed to reduce uncertainties in future assessment.

  2. Plant responses to increasing CO2 reduce estimates of climate impacts on drought severity (United States)

    Swann, Abigail L. S.; Hoffman, Forrest M.; Koven, Charles D.; Randerson, James T.


    Rising atmospheric CO2 will make Earth warmer, and many studies have inferred that this warming will cause droughts to become more widespread and severe. However, rising atmospheric CO2 also modifies stomatal conductance and plant water use, processes that are often are overlooked in impact analysis. We find that plant physiological responses to CO2 reduce predictions of future drought stress, and that this reduction is captured by using plant-centric rather than atmosphere-centric metrics from Earth system models (ESMs). The atmosphere-centric Palmer Drought Severity Index predicts future increases in drought stress for more than 70% of global land area. This area drops to 37% with the use of precipitation minus evapotranspiration (P-E), a measure that represents the water flux available to downstream ecosystems and humans. The two metrics yield consistent estimates of increasing stress in regions where precipitation decreases are more robust (southern North America, northeastern South America, and southern Europe). The metrics produce diverging estimates elsewhere, with P-E predicting decreasing stress across temperate Asia and central Africa. The differing sensitivity of drought metrics to radiative and physiological aspects of increasing CO2 partly explains the divergent estimates of future drought reported in recent studies. Further, use of ESM output in offline models may double-count plant feedbacks on relative humidity and other surface variables, leading to overestimates of future stress. The use of drought metrics that account for the response of plant transpiration to changing CO2, including direct use of P-E and soil moisture from ESMs, is needed to reduce uncertainties in future assessment.

  3. Surface-downhole and crosshole geoelectrics for monitoring of brine injection at the Ketzin CO2 storage site (United States)

    Rippe, Dennis; Bergmann, Peter; Labitzke, Tim; Wagner, Florian; Schmidt-Hattenberger, Cornelia


    The Ketzin pilot site in Germany is the longest operating on-shore CO2 storage site in Europe. From June 2008 till August 2013, a total of ˜67,000 tonnes of CO2 were safely stored in a saline aquifer at depths of 630 m to 650 m. The storage site has now entered the abandonment phase, and continuation of the multi-disciplinary monitoring as part of the national project "CO2 post-injection monitoring and post-closure phase at the Ketzin pilot site" (COMPLETE) provides the unique chance to participate in the conclusion of the complete life cycle of a CO2 storage site. As part of the continuous evaluation of the functionality and integrity of the CO2 storage in Ketzin, from October 12, 2015 till January 6, 2015 a total of ˜2,900 tonnes of brine were successfully injected into the CO2 reservoir, hereby simulating in time-lapse the natural backflow of brine and the associated displacement of CO2. The main objectives of this brine injection experiment include investigation of how much of the CO2 in the pore space can be displaced by brine and if this displacement of CO2 during the brine injection differs from the displacement of formation fluid during the initial CO2 injection. Geophysical monitoring of the brine injection included continuous geoelectric measurements accompanied by monitoring of pressure and temperature conditions in the injection well and two adjacent observation wells. During the previous CO2 injection, the geoelectrical monitoring concept at the Ketzin pilot site consisted of permanent crosshole measurements and non-permanent large-scale surveys (Kiessling et al., 2010). Time-lapse geoelectrical tomographies derived from the weekly crosshole data at near-wellbore scale complemented by six surface-downhole surveys at a scale of 1.5 km showed a noticeable resistivity signature within the target storage zone, which was attributed to the CO2 plume (Schmidt-Hattenberger et al., 2011) and interpreted in terms of relative CO2 and brine saturations (Bergmann

  4. CO2 evasion from boreal lakes: Revised estimate, drivers of spatial variability, and future projections. (United States)

    Hastie, Adam; Lauerwald, Ronny; Weyhenmeyer, Gesa; Sobek, Sebastian; Verpoorter, Charles; Regnier, Pierre


    Lakes (including reservoirs) are an important component of the global carbon (C) cycle, as acknowledged by the fifth assessment report of the IPCC. In the context of lakes, the boreal region is disproportionately important contributing to 27% of the worldwide lake area, despite representing just 14% of global land surface area. In this study, we used a statistical approach to derive a prediction equation for the partial pressure of CO2 (pCO2 ) in lakes as a function of lake area, terrestrial net primary productivity (NPP), and precipitation (r(2)  = .56), and to create the first high-resolution, circumboreal map (0.5°) of lake pCO2 . The map of pCO2 was combined with lake area from the recently published GLOWABO database and three different estimates of the gas transfer velocity k to produce a resulting map of CO2 evasion (FCO2 ). For the boreal region, we estimate an average, lake area weighted, pCO2 of 966 (678-1,325) μatm and a total FCO2 of 189 (74-347) Tg C year(-1) , and evaluate the corresponding uncertainties based on Monte Carlo simulation. Our estimate of FCO2 is approximately twofold greater than previous estimates, as a result of methodological and data source differences. We use our results along with published estimates of the other C fluxes through inland waters to derive a C budget for the boreal region, and find that FCO2 from lakes is the most significant flux of the land-ocean aquatic continuum, and of a similar magnitude as emissions from forest fires. Using the model and applying it to spatially resolved projections of terrestrial NPP and precipitation while keeping everything else constant, we predict a 107% increase in boreal lake FCO2 under emission scenario RCP8.5 by 2100. Our projections are largely driven by increases in terrestrial NPP over the same period, showing the very close connection between the terrestrial and aquatic C cycle. © 2017 John Wiley & Sons Ltd.

  5. Communicating CCS. Effects of text-only and text-and-visual depictions of CO2 storage on risk perceptions and attitudes

    Energy Technology Data Exchange (ETDEWEB)

    Brunsting, S.; De Best-Waldhober, M.; Brouwer, A.S. [ECN Policy Studies, Amsterdam (Netherlands); Riesch, H.; Reiner, D. [Cambridge University, Cambridge (United Kingdom)


    This experiment aims to increase understanding of the conditions under which combining textual and visual information on CO2 storage fosters comprehension of the technology. Specifically, it is investigated if and how precision in indicating the depth of CO2 injection in either text, visual, or combinations thereof influence estimates of CO2 injection depth and how this in turn influences perceived safety of and attitude towards CO2 injection. We used a 3x3 experimental design with two factors, resulting in 9 conditions: Textual description of depth of injection (absent, ambiguous, precise) X visualization of depth (absent, ambiguous, precise). Three texts were developed explaining the background and process of CCS. They were similar in every respect except for the accuracy of indication of depth: Absent ( 'underground'); Ambiguous ('deep underground'); Precise ('1,000 meters or deeper underground'). Three visual conditions were developed displaying the depth of CO2 injection. They were similar in every respect except for the accuracy of indication of depth: Absent (no visual displayed); Ambiguous (visual not to scale, injection obviously too shallow); Precise (visual to scale). Respondents were a representative sample of the adult UK population (n = 429). Each of them received one of the nine conditions, followed by a short questionnaire. Results indicate that estimates of depth are generally most accurate in text-only conditions and least accurate in visual-only conditions. Interestingly, the condition in which people are given no information about depth at all scores in-between with a mean estimate of 869 meters. Regarding textual depictions of CO2 injection depth, results indicate that the more precise indication of depth in the text the better respondents' estimate of depth, but this effect is only found for respondents who enjoy reading text. Regarding visual depictions of CO2 injection, results indicate that the presence of a visual worsens respondents

  6. Best practice guidance for environmental risk assessment for offshore CO2 geological storage

    NARCIS (Netherlands)

    Wallmann, K.; Haeckel, M.; Linke, P.; Haffert, L.; Schmidt, M.; Buenz, S.; James, R.; Hauton, C.; Tsimplis, M.; Widdicombe, S.; Blackford, J.; Queiros, A.M.; Connelly, D.; Lichtschlag, A.; Dewar, M.; Chen, B.; Baumberger, T.; Beaubin, S.; Vercelli, S.; Proells, A.; Wildenborg, A.F.B.; Mikunda, T.; Nepveu, M.; Maynard, C.; Finnerty, S.; Flach, T.; Ahmed, N.; Ulfsnes, A.; Brooks, L.; Moskeland, T.; Purcll, M.


    Carbon dioxide (CO2) separated from natural gas has been stored successfully below the seabed off Norway for almost two decades. Based on these experiences several demonstration projects supported by the EU and its member states are now setting out to store CO2 captured at power plants in offshore

  7. Regional inversion of CO2 ecosystem fluxes from atmospheric measurements. Reliability of the uncertainty estimates

    Energy Technology Data Exchange (ETDEWEB)

    Broquet, G.; Chevallier, F.; Breon, F.M.; Yver, C.; Ciais, P.; Ramonet, M.; Schmidt, M. [Laboratoire des Sciences du Climat et de l' Environnement, CEA-CNRS-UVSQ, UMR8212, IPSL, Gif-sur-Yvette (France); Alemanno, M. [Servizio Meteorologico dell' Aeronautica Militare Italiana, Centro Aeronautica Militare di Montagna, Monte Cimone/Sestola (Italy); Apadula, F. [Research on Energy Systems, RSE, Environment and Sustainable Development Department, Milano (Italy); Hammer, S. [Universitaet Heidelberg, Institut fuer Umweltphysik, Heidelberg (Germany); Haszpra, L. [Hungarian Meteorological Service, Budapest (Hungary); Meinhardt, F. [Federal Environmental Agency, Kirchzarten (Germany); Necki, J. [AGH University of Science and Technology, Krakow (Poland); Piacentino, S. [ENEA, Laboratory for Earth Observations and Analyses, Palermo (Italy); Thompson, R.L. [Max Planck Institute for Biogeochemistry, Jena (Germany); Vermeulen, A.T. [Energy research Centre of the Netherlands ECN, EEE-EA, Petten (Netherlands)


    The Bayesian framework of CO2 flux inversions permits estimates of the retrieved flux uncertainties. Here, the reliability of these theoretical estimates is studied through a comparison against the misfits between the inverted fluxes and independent measurements of the CO2 Net Ecosystem Exchange (NEE) made by the eddy covariance technique at local (few hectares) scale. Regional inversions at 0.5{sup 0} resolution are applied for the western European domain where {approx}50 eddy covariance sites are operated. These inversions are conducted for the period 2002-2007. They use a mesoscale atmospheric transport model, a prior estimate of the NEE from a terrestrial ecosystem model and rely on the variational assimilation of in situ continuous measurements of CO2 atmospheric mole fractions. Averaged over monthly periods and over the whole domain, the misfits are in good agreement with the theoretical uncertainties for prior and inverted NEE, and pass the chi-square test for the variance at the 30% and 5% significance levels respectively, despite the scale mismatch and the independence between the prior (respectively inverted) NEE and the flux measurements. The theoretical uncertainty reduction for the monthly NEE at the measurement sites is 53% while the inversion decreases the standard deviation of the misfits by 38 %. These results build confidence in the NEE estimates at the European/monthly scales and in their theoretical uncertainty from the regional inverse modelling system. However, the uncertainties at the monthly (respectively annual) scale remain larger than the amplitude of the inter-annual variability of monthly (respectively annual) fluxes, so that this study does not engender confidence in the inter-annual variations. The uncertainties at the monthly scale are significantly smaller than the seasonal variations. The seasonal cycle of the inverted fluxes is thus reliable. In particular, the CO2 sink period over the European continent likely ends later than

  8. Comparison of Publically Available Methodologies for Development of Geologic Storage Estimates for Carbon Dioxide in Saline Formations (United States)

    Goodman, A.; Strazisar, B. R.; Guthrie, G. D.; Bromhal, G.


    High-level estimates of CO2 storage potential at the national, regional, and basin scale are required to assess the potential for carbon capture, utilization, and storage (CCUS) technologies to reduce CO2 emissions for application to saline formations. Both private and public entities worldwide rely on CO2 storage potential estimates for broad energy-related government policy and business decisions. High-level estimates of CO2 geologic storage potential, however, have a high degree of uncertainty because the assessments rely on simplifying assumptions due to the deficiency or absence of data from the subsurface associated with areas of potential storage in saline formations and the natural heterogeneity of geologic formations in general, resulting in undefined rock properties. As site characterization progresses to individual CO2 storage sites, additional site-specific data will likely be collected and analyzed that will allow for the refinement of high-level CO2 storage resource estimates and development of CO2 storage capacities. Until such detailed characterization can be documented, dependable high-level CO2 storage estimates are essential to ensure successful widespread deployment of CCUS technologies. Initiatives for assessing CO2 geologic storage potential have been conducted since 1993. Although dependable high-level CO2 storage estimates are essential to ensure successful deployment of CCUS technologies, it is difficult to assess the uncertainty of these estimates without knowing how the current methodologies targeted at high-level CO2 storage resource estimates for saline formations compare to one another. In this study, we compare high-level CO2 methodologies for development of geologic storage estimates for CO2 in saline formations to assess the uncertainty associated with various methodologies. The methodologies applied are listed as follows: (1) U.S. DOE Methodology: Development of Geologic Storage Potential for Carbon Dioxide at the National and

  9. Estimating Interfacial Curvature To Assess The Impact Of Ostwald Ripening On The Stability Of Residually Trapped CO2 (United States)

    de Chalendar, J.; Garing, C.; Benson, S. M.


    The stability of residually trapped CO2 is often taken for granted in the simulation studies used for predicting the long-term fate of CO2 in geological storage reservoirs. Ostwald ripening is one of the mechanisms that could potentially remobilize residually trapped CO2. This would cause the gradual growth of ganglia with low capillary pressures, at the expense of ganglia with higher capillary pressure. Ostwald ripening will be driven by differences in capillary pressure between ganglia, and subsequent diffusion of dissolved CO2 through the aqueous phase. Therefore, a critical question is to understand the distribution of capillary pressure in isolated ganglia. The goal of this study is to develop reliable methods for estimating capillary pressure of individual ganglia of gases that are trapped during imbibition. Multi-resolution X-ray microtomography datasets from air-water spontaneous imbibition experiments in sintered glass beads and sandstone samples with voxel sizes varying from 0.64 to 4.44 µm were acquired at the Advanced Light Source, in Lawrence Berkeley National Laboratory. A series of computational techniques to estimate curvature at the interface between two immiscible fluids in porous were developed. In a first step, isosurfaces are extracted using resources from MATLAB's Image Processing Toolbox or the Avizo software suite resulting in a triagonal mesh representing the considered surfaces. A second step is to identify and separate the interfaces between each of the three phases. The mesh is then smoothed and its curvature is estimated. The sensitivity of results to different curvature estimation and smoothing techniques is studied. Estimating curvature on unsmoothed meshes shows a high degree of sensitivity to the resolution of the images, as well as the method chosen to calculate curvature. When the mesh is smoothed using a heat diffusion method however, curvature estimation using different methods and resolutions converges, as verified by

  10. Optimization of CO2 Storage in Saline Aquifers Using Water-Alternating Gas (WAG) Scheme - Case Study for Utsira Formation (United States)

    Agarwal, R. K.; Zhang, Z.; Zhu, C.


    For optimization of CO2 storage and reduced CO2 plume migration in saline aquifers, a genetic algorithm (GA) based optimizer has been developed which is combined with the DOE multi-phase flow and heat transfer numerical simulation code TOUGH2. Designated as GA-TOUGH2, this combined solver/optimizer has been verified by performing optimization studies on a number of model problems and comparing the results with brute-force optimization which requires a large number of simulations. Using GA-TOUGH2, an innovative reservoir engineering technique known as water-alternating-gas (WAG) injection has been investigated to determine the optimal WAG operation for enhanced CO2 storage capacity. The topmost layer (layer # 9) of Utsira formation at Sleipner Project, Norway is considered as a case study. A cylindrical domain, which possesses identical characteristics of the detailed 3D Utsira Layer #9 model except for the absence of 3D topography, was used. Topographical details are known to be important in determining the CO2 migration at Sleipner, and are considered in our companion model for history match of the CO2 plume migration at Sleipner. However, simplification on topography here, without compromising accuracy, is necessary to analyze the effectiveness of WAG operation on CO2 migration without incurring excessive computational cost. Selected WAG operation then can be simulated with full topography details later. We consider a cylindrical domain with thickness of 35 m with horizontal flat caprock. All hydrogeological properties are retained from the detailed 3D Utsira Layer #9 model, the most important being the horizontal-to-vertical permeability ratio of 10. Constant Gas Injection (CGI) operation with nine-year average CO2 injection rate of 2.7 kg/s is considered as the baseline case for comparison. The 30-day, 15-day, and 5-day WAG cycle durations are considered for the WAG optimization design. Our computations show that for the simplified Utsira Layer #9 model, the

  11. A comparison of electricity and hydrogen production systems with CO2 capture and storage. Part B: Chain analysis of promising CCS options

    NARCIS (Netherlands)

    Damen, K.J.; van Troost, M.M.; Faaij, A.P.C.|info:eu-repo/dai/nl/10685903X; Turkenburg, W.C.|info:eu-repo/dai/nl/073416355


    Promising electricity and hydrogen production chains with CO2 capture, transport and storage (CCS) and energy carrier transmission, distribution and end-use are analysed to assess (avoided) CO2 emissions, energy production costs and CO2 mitigation costs. For electricity chains, the performance is

  12. New Strategies for Finding Abandoned Wells at Proposed Geologic Storage Sites for CO2

    Energy Technology Data Exchange (ETDEWEB)

    Hammack, R.W.; Veloski, G.A.


    Prior to the injection of CO2 into geological formations, either for enhanced oil recovery or for CO2 sequestration, it is necessary to locate wells that perforate the target formation and are within the radius of influence for planned injection wells. Locating and plugging wells is necessary because improperly plugged well bores provide the most rapid route for CO2 escape to the surface. This paper describes the implementation and evaluation of helicopter and ground-based well detection strategies at a 100+ year old oilfield in Wyoming where a CO2 flood is planned. This project was jointly funded by the U.S. Department of Energy’s National Energy Technology Laboratory and Fugro Airborne Surveys.

  13. Characterization of Qatar's surface carbonates for CO2 capture and thermochemical energy storage (United States)

    Kakosimos, Konstantinos E.; Al-Haddad, Ghadeer; Sakellariou, Kyriaki G.; Pagkoura, Chrysa; Konstandopoulos, Athanasios G.


    Samples of surface carbonates were collected from three different areas of the Qatar peninsula. We employed material characterization techniques to examine the morphology and composition of the samples, while their CO2 capture capacity was assessed via multiple successive calcination-carbonation cycles. Our samples were mainly calcite and dolomite based. Calcite samples showed higher initial capacity of around 11 mmol CO2 g-1 which decayed rapidly to less than 2 mmol CO2 g-1. On the other hand, dolomite samples showed an excellent stability (˜15 cycles) with a capacity of 6 mmol CO2 g-1. The performance of the dolomite samples is better compared to other similar natural samples, from literature. A promising result for future studies towards improving their performance by physical and chemical modification.

  14. The Smart Grid: An Estimation of the Energy and CO2 Benefits

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, Robert G.; Balducci, Patrick J.; Gerkensmeyer, Clint; Katipamula, Srinivas; Kintner-Meyer, Michael CW; Sanquist, Thomas F.; Schneider, Kevin P.; Secrest, Thomas J.


    This report articulates nine mechanisms by which the smart grid can reduce energy use and carbon impacts associated with electricity generation and delivery. The quantitative estimates of potential reductions in electricity sector energy and associated CO2 emissions presented are based on a survey of published results and simple analyses. This report does not attempt to justify the cost effectiveness of the smart grid, which to date has been based primarily upon the twin pillars of cost-effective operation and improved reliability. Rather, it attempts to quantify the additional energy and CO2 emission benefits inherent in the smart grid’s potential contribution to the nation’s goal of mitigating climate change by reducing the carbon footprint of the electric power system.

  15. The Smart Grid: An Estimation of the Energy and CO2 Benefits

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, Robert G.; Balducci, Patrick J.; Gerkensmeyer, Clint; Katipamula, Srinivas; Kintner-Meyer, Michael CW; Sanquist, Thomas F.; Schneider, Kevin P.; Secrest, Thomas J.


    This report articulates nine mechanisms by which the smart grid can reduce energy use and carbon impacts associated with electricity generation and delivery. The quantitative estimates of potential reductions in electricity sector energy and associated CO2 emissions presented are based on a survey of published results and simple analyses. This report does not attempt to justify the cost effectiveness of the smart grid, which to date has been based primarily upon the twin pillars of cost-effective operation and improved reliability. Rather, it attempts to quantify the additional energy and CO2 emission benefits inherent in the smart grid’s potential contribution to the nation’s goal of mitigating climate change by reducing the carbon footprint of the electric power system.

  16. Quantification of oil recovery efficiency, CO 2 storage potential, and fluid-rock interactions by CWI in heterogeneous sandstone oil reservoirs

    DEFF Research Database (Denmark)

    Seyyedi, Mojtaba; Sohrabi, Mehran; Sisson, Adam


    Significant interest exists in improving recovery from oil reservoirs while addressing concerns about increasing CO2 concentrations in the atmosphere. The combination of Enhanced Oil Recovery (EOR) and safe geologic storage of CO2 in oil reservoirs is appealing and can be achieved by carbonated (...... for oil recovery and CO2 storage potential on heterogeneous cores. Since not all the oil reservoirs are homogenous, understanding the potential of CWI as an integrated EOR and CO2 storage scenario in heterogeneous oil reservoirs is essential.......Significant interest exists in improving recovery from oil reservoirs while addressing concerns about increasing CO2 concentrations in the atmosphere. The combination of Enhanced Oil Recovery (EOR) and safe geologic storage of CO2 in oil reservoirs is appealing and can be achieved by carbonated (CO...

  17. Investigation of Transient, Turbulent Natural Convection in Vertical Tubes for Thermal Energy Storage in Supercritical CO2 (United States)

    Baghaei Lakeh, Reza; Lavine, Adrienne S.; Kavehpour, H. Pirouz; Wirz, Richard E.


    Heat transfer can be a limiting factor in the operation of thermal energy storage, including sensible heat and latent heat storage systems. Poor heat transfer between the energy storage medium and the container walls impairs the functionality of the thermal storage unit by requiring excessively long times to charge or discharge the system. In this study, the effect of turbulent, unsteady buoyancy-driven flow on heat transfer in vertical storage tubes containing supercritical CO2 as the storage medium is investigated computationally. The heat transfer from a constant-temperature wall to the storage fluid is studied during the charge cycle. The results of this study show that turbulent natural convection dominates the heat transfer mechanism and significantly reduces the required time for charging compared to pure conduction. Changing the L/D ratio of the storage tube has a major impact on the charge time. The charge time shows a decreasing trend with RaL. The non-dimensional model of the problem shows that Nusselt number and non-dimensional mean temperature of the storage fluid in different configurations of the tube is a function Buoyancy-Fourier number defined as of FoL * RaLm* L/D. This study was supported by award No. DE-AR0000140 granted by U.S. Department of Energy under Advanced Research Projects Agency - Energy (ARPA-E) and by award No. 5660021607 granted by Southern California Gas Company.

  18. Advanced and Integrated Petrophysical Characterization for CO2 Storage: Application to the Ketzin Site Caractérisation pétrophysique intégrée pour le stockage de CO2 : application au site de Ketzin

    Directory of Open Access Journals (Sweden)

    Fleury M.


    Full Text Available Advanced and Integrated Petrophysical Characterization for CO2 Storage: Application to the Ketzin Site — Reservoir simulations and monitoring of CO2 storage require specific petrophysical data. We show a workflow that can be applied to saline aquifers and caprocks in order to provide the minimum data set for realistic estimations of storage potential and perform pertinent simulations of CO2 injection. The presented series of experiments are fully integrated with quantitative log data analysis to estimate porosity, irreducible saturation, drainage capillary pressure and water relative permeability, residual gas saturation, resistivity-saturation relationships and caprock transport properties (permeability and diffusivity. The case considered is a saline aquifer of the Triassic Stuttgart formation studied in the framework of the CO2SINK onshore research storage, the first in situ testing site of CO2 injection in Germany located near the city of Ketzin. We used petrophysical methods that can provide the required data in a reasonable amount of time while still being representative of the in situ injection process. For two phase transport properties, we used the centrifuge technique. For resistivity measurements, we used the Fast Resistivity Index Measurement (FRIM method in drainage and imbibition, at ambient and storage conditions. For caprock characterization, we used a fast NMR (Nuclear Magnetic Resonance deuterium tracer technique to measure diffusivity and a modified steady state innovative technique to determine permeability. Entry pressure has also been evaluated using several methods. Resistivity and NMR logs were analyzed to provide a continuous estimation of irreducible saturation for the entire storage zone and to judge on the representativity of the samples analyzed in the laboratory. For the Ketzin site, the storage zone is a clayey sandstone of fluvial origin locally highly cemented, with porosity around 30% and permeability ranging

  19. Risk Assessment and Management for Long-Term Storage of CO2 in Geologic Formations — United States Department of Energy R&D

    Directory of Open Access Journals (Sweden)

    Dawn Deel


    Full Text Available Concern about increasing atmospheric concentrations of carbon dioxide (CO2 and other greenhouse gases (GHG and their impact on the earth's climate has grown significantly over the last decade. Many countries, including the United States, wrestle with balancing economic development and meeting critical near-term environmental goals while minimizing long-term environmental risks. One promising solution to the buildup of GHGs in the atmosphere, being pursued by the U.S. Department of Energy's (DOE National Energy Technology Laboratory (NETL and its industrial and academic partners, is carbon sequestration—a process of permanent storage of CO2 emissions in underground geologic formations, thus avoiding CO2 release to the atmosphere. This option looks particularly attractive for point source emissions of GHGs, such as fossil fuel fired power plants. CO2 would be captured, transported to a sequestration site, and injected into an appropriate geologic formation. However, sequestration in geologic formations cannot achieve a significant role in reducing GHG emissions unless it is acceptable to stakeholders, regulators, and the general public, i.e., unless the risks involved are judged to be acceptable. One tool that can be used to achieve acceptance of geologic sequestration of CO2 is risk assessment, which is a proven method to objectively manage hazards in facilities such as oil and natural gas fields, pipelines, refineries, and chemical plants. Although probabilistic risk assessment (PRA has been applied in many areas, its application to geologic CO2 sequestration is still in its infancy. The most significant risk from geologic carbon sequestration is leakage of CO2. Two types of CO2 releases are possible—atmospheric and subsurface. High concentrations of CO2 caused by a release to the atmosphere would pose health risks to humans and animals, and any leakage of CO2 back into the atmosphere negates the effort expended to sequester the CO2

  20. Fluorous Metal-Organic Frameworks with Enhanced Stability and High H2/CO2 Storage Capacities (United States)

    Zhang, Da-Shuai; Chang, Ze; Li, Yi-Fan; Jiang, Zhong-Yi; Xuan, Zhi-Hong; Zhang, Ying-Hui; Li, Jian-Rong; Chen, Qiang; Hu, Tong-Liang; Bu, Xian-He


    A new class of metal-organic frameworks (MOFs) has been synthesized by ligand-functionalization strategy. Systematic studies of their adsorption properties were performed at low and high pressure. Importantly, when fluorine was introduced into the framework via the functionalization, both the framework stabilities and adsorption capacities towards H2/CO2 were enhanced significantly. This consequence can be well interpreted by theoretical studies of these MOFs structures. In addition, one of these MOFs TKL-107 was used to fabricate mixed matrix membranes, which exhibit great potential for the application of CO2 separation. PMID:24264725

  1. Reaction-driven cracking during hydration and carbonation of olivine: Implications for in situ CO2 capture and storage (United States)

    Kelemen, P. B.; Hirth, G.


    Reactions forming serpentine and/or Mg-carbonates via reaction of fluid with olivine may increase the solid volume, due to increasing solid mass and decreasing solid density, provided that fluid is supplied in an open system, and that dissolution does not remove significant solid mass. Increasing solid volume can create deviatoric stress within a rock, potentially causing fracture. In turn, this can provide a positive feedback to the alteration process, maintaining or increasing permeability and reactive surface area. This could be important - or even essential - for proposed in situ mineral carbonation for CO2 storage, and potentially for geological CO2 capture from surface waters. We use several methods to estimate the 'force of crystallization' during hydration and carbonation of olivine. The free energy changes driving these processes can potentially generate overpressures of 100's to 1000's of MPa. These potential stresses are larger for a given temperature for carbonation compared to serpentinization. Thermodynamic upper bounds can be compared to estimates based on microstructure in natural samples. Evans (Int Geol Rev 2004) and Jamtveit et al. (EPSL 2008) provide microphotographs of igneous troctolites, with interstitial plagioclase surrounding rounded olivine grains. The olivine grains are partially serpentinized, and the plagioclase has closely spaced fractures interpreted as a result of expansion during serpentinization. Strain energy due to expansion should be greater than surface energy on new fractures. Spacing and length of fractures in plagioclase yields a minimum of about 260 MPa for the differential stress. Alternatively, if fractures did not form, elastic stress in the plagioclase resulting from expansion during serpentinization should be proportional to the strain. Because some strain could be accommodated by irreversible mechanisms, such as friction and dilation on cracks and/or viscous flow, this yields a maximum stress of 270 MPa. The close

  2. The potential of geological storage of CO2 in Austria: a techno-economic assessment

    NARCIS (Netherlands)

    Brüstle, Anna Katharina; Welkenhuysen, Kris; Bottig, Magdalena; Piessens, Kris; Ramirez, Andrea|info:eu-repo/dai/nl/284852414; Swenner, Rudy

    An impressive two-third or about 40GWh/y of electricity in Austria is produced from renewable energy sources, in particular hydro energy. For the remaining part the country depends on fossil fuels, which together with iron & steel production form the most CO2 intensive industries in Austria with a

  3. Tagging CO2 to Enable Quantitative Inventories of Geological Carbon Storage

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, Klaus; Matter, Juerg; Park, Ah-Hyung; Stute, Martin; Carson, Cantwell; Ji, Yinghuang


    In the wake of concerns about the long term integrity and containment of sub-surface CO2 sequestration reservoirs, many efforts have been made to improve the monitoring, verification, and accounting methods for geo-sequestered CO2. Our project aimed to demonstrate the feasibility of a system designed to tag CO2 with carbon isotope 14C immediately prior to sequestration to a level that is normal on the surface (one part per trillion). Because carbon found at depth is naturally free of 14C, this tag would easily differentiate pre-existing carbon from anthropogenic injected carbon and provide an excellent handle for monitoring its whereabouts in the subsurface. It also creates an excellent handle for adding up anthropogenic carbon inventories. Future inventories in effect count 14C atoms. Accordingly, we have developed a 14C tagging system suitable for use at the part-per-trillion level. This system consists of a gas-exchange apparatus to make disposable cartridges ready for controlled injection into a fast flowing stream of pressurized CO2. We built a high-pressure injection and tagging system, and a 14C detection system. The disposable cartridge and injection system have been successfully demonstrated in the lab with a high-pressure flow reactor, as well as in the field at the CarbFix CO2 sequestration site in Iceland. The laser-based 14C detection system originally conceived has been shown to possess inadequate sensitivity for ambient levels. Alternative methods for detecting 14C, such as saturated cavity absorption ringdown spectroscopy and scintillation counting, may still be suitable. KEYWORDS

  4. Continental-scale enrichment of atmospheric 14CO2 from the nuclear power industry: potential impact on the estimation of fossil fuel-derived CO2

    Directory of Open Access Journals (Sweden)

    N. Gruber


    Full Text Available The 14C-free fossil carbon added to atmospheric CO2 by combustion dilutes the atmospheric 14C/C ratio (Δ14C, potentially providing a means to verify fossil CO2 emissions calculated using economic inventories. However, sources of 14C from nuclear power generation and spent fuel reprocessing can counteract this dilution and may bias 14C/C-based estimates of fossil fuel-derived CO2 if these nuclear influences are not correctly accounted for. Previous studies have examined nuclear influences on local scales, but the potential for continental-scale influences on Δ14C has not yet been explored. We estimate annual 14C emissions from each nuclear site in the world and conduct an Eulerian transport modeling study to investigate the continental-scale, steady-state gradients of Δ14C caused by nuclear activities and fossil fuel combustion. Over large regions of Europe, North America and East Asia, nuclear enrichment may offset at least 20% of the fossil fuel dilution in Δ14C, corresponding to potential biases of more than −0.25 ppm in the CO2 attributed to fossil fuel emissions, larger than the bias from plant and soil respiration in some areas. Model grid cells including high 14C-release reactors or fuel reprocessing sites showed much larger nuclear enrichment, despite the coarse model resolution of 1.8°×1.8°. The recent growth of nuclear 14C emissions increased the potential nuclear bias over 1985–2005, suggesting that changing nuclear activities may complicate the use of Δ14C observations to identify trends in fossil fuel emissions. The magnitude of the potential nuclear bias is largely independent of the choice of reference station in the context of continental-scale Eulerian transport and inversion studies, but could potentially be reduced by an appropriate choice of reference station in the context of local-scale assessments.

  5. A Study on Seismic Hazard Evaluation at the Nagaoka CO2 Storage Site, Japan (United States)

    Horikawa, S.


    RITE carried out the first Japanese pilot-scale CO2 sequestration project from July, 2003 to January, 2005 in Nagaoka City.Supercritical CO2 was injected into an onshore saline aquifer at a depth of 1,100m. CO2 was injected at a rate of 10,400 tonnes. 'Mid Niigata Prefecture Earthquake in 2004' (Mw6.6) and 'The Niigataken Chuetsu-oki Earthquake in 2007' (Mw6.6) occurred during the CO2 injection-test and after the completion of injection-test. Japan is one of the world's major countries with frequent earthquakes.This paper presents a result of seismic response analysis, and reports of seismic hazard evaluation of a reservoir and a caprock. In advance of dynamic response analysis, the earthquake motion recorded on the earth surface assumed the horizontally layer model, and set up the input wave from a basement layer by SHAKE ( = One-Dimensional Seismic Response Analysis). This wave was inputted into the analysis model and the equation of motion was solved using the direct integral calculus by Newmark Beta Method. In Seismic Response Analysis, authors have used Multiple Yield Model (MYM, Iwata, et al., 2013), which can respond also to complicated geological structure. The intensity deformation property of the foundation added the offloading characteristic to the composition rule of Duncan-Chang model in consideration of confining stress dependency, and used for and carried out the nonlinear repetition model. And the deformation characteristic which made it depend on confining stress with the cyclic loadings and un-loadings, and combined Mohr-Coulomb's law as a strength characteristic.The maximum dynamic shearing strain of caprock was generated about 1.1E-04 after the end of an earthquake. Although the dynamic safety factor was 1.925 on the beginning, after the end of an earthquake fell 0.05 point. The dynamic safety factor of reservoir fell to 1.20 from 1.29. As a result of CO2 migration monitoring by the seismic cross-hole tomography, CO2 has stopped in the reservoir

  6. Malate metabolism and adaptation to chilling temperature storage by pretreatment with high CO2 levels in Annona cherimola fruit. (United States)

    Maldonado, Roberto; Sanchez-Ballesta, M Teresa; Alique, Rafael; Escribano, M Isabel; Merodio, Carmen


    In this study we focused on the effect of a pretreatment with high (20%) CO2 levels on malic acid metabolism in cherimoya (Annona cherimola Mill) fruit stored at chilling temperature. We analyzed the activity of phosphoenolpyruvate carboxylase (PEPC), malate dehydrogenase (MDH), and the NADP-malic enzyme (NADP-ME), involved in the carboxylation/decarboxylation of malate. Our results show that CO2 treatment, which improves tolerance to prolonged storage at chilling temperature, was closely linked to considerably greater NADP-ME activity. These results, combined with lower PEPC activity, may explain the significantly lower amount of malic acid and titratable acidity quantified in CO2-treated fruit. Moreover, the high cytoplasmic MDH enzyme activity and the strong stimulation of NADP-ME activity exhibited by CO2-treated fruit could be contributing factors in the maintenance of fruit energy metabolism, pH stability, and the promotion of synthesis of defense compounds that prevent or repair damage caused by chilling temperature. Copyright 2004 American Chemical Society

  7. Comparison of methods for estimating carbon dioxide storage by Sacramento's urban forest (United States)

    Elena Aguaron; E. Gregory McPherson


    Limited open-grown urban tree species biomass equations have necessitated use of forest-derived equations with diverse conclusions on the accuracy of these equations to estimate urban biomass and carbon storage. Our goal was to determine and explain variability among estimates of CO2 storage from four sets of allometric equations for the same...

  8. A SAFT Equation of State for the H2S-CO2-H2O-NaCl system and applications for CO2 - H2S transportation and geological storage


    Ji, Xiaoyan; Zhu, Chen


    When H2S is co-injected with CO2, we need to know thermodynamic properties and phase equilibria for the CO2-H2S- H2O-NaCl system in order to evaluate the sequestration capacity, optimal transportation and injection conditions, potential for pipeline corrosion, and increased risk of storage and leakage. Here, we summarize the results of the phase equilibrium and densities for CO2-sequestration related systems from a thermodynamic model that is based on statistical associating fluid theory equa...

  9. The DELPHI expert process of the German umbrella project AUGE as basis for recommendations to CO2 storage in Germany (United States)

    Pilz, Peter; Schoebel, Birgit; Liebscher, Axel


    Within the GEOTECHNOLOGIEN funding scheme for geological CO2 storage by the Federal Ministry of Education and Research (BMBF) in Germany 33 projects (135 subprojects) have been funded with a total budget of 58 Mio € (excluding industry funds) from 2005 to 2014. In 2012, the German parliament passed the transposition of the EU CCS Directive 2009/31/EG into the national "Carbon Dioxide Storage Law" (KSpG). Annex 1 of the KSpG provides a description of criteria for the characterization and assessment of a potential CO2 storage site. Annex 2 describes the expected monitoring system of a CO2 storage site. The criteria given in the appendices are of general nature, which reflects (1) that the CO2 storage technology is still being developed and (2) that site specific aspects needs to be considered. In 2012 an umbrella project called AUGE has been launched in order to compile and summarize the results of the GEOTECHNOLOGIEN projects to underpin the two Annexes scientifically. By integration of the individual project results AUGE aims at derive recommendations for the review and implementation of the KSpG. The recommendations shall be drafted based on a common ground of science, public authorities and industry. Therefore, the AUGE project includes a Delphi expert process as an essential part. It is realized in cooperation with the company COMPARE Consulting, Göppingen. The implementation of the Delphi-Process is organized in three steps: • After the technical preparation of a standardized questionnaire (2014/2015) it was sent to 129 experts from science, industry and public authorities in Germany. After a few weeks of consideration time, 40 persons (30 %) had decided to participate actively in this inquiry. • Following the results of the first interrogation campaign, the second survey campaign started at the end of 2015. The same list of questions was used, complemented with the results of the first inquiry campaign. The intention is reduce the variance of the

  10. Continuous atmospheric monitoring of the injected CO2 behavior over geological storage sites using flux stations: latest technologies and resources (United States)

    Burba, George; Madsen, Rodney; Feese, Kristin


    Flux stations have been widely used to monitor emission rates of CO2 from various ecosystems for climate research for over 30 years [1]. The stations provide accurate and continuous measurements of CO2 emissions with high temporal resolution. Time scales range from 20 times per second for gas concentrations, to 15-minute, hourly, daily, and multi-year periods. The emissions are measured from the upwind area ranging from thousands of square meters to multiple square kilometers, depending on the measurement height. The stations can nearly instantaneously detect rapid changes in emissions due to weather events, as well as changes caused by variations in human-triggered events (pressure leaks, control releases, etc.). Stations can also detect any slow changes related to seasonal dynamics and human-triggered low-frequency processes (leakage diffusion, etc.). In the past, station configuration, data collection and processing were highly-customized, site-specific and greatly dependent on "school-of-thought" practiced by a particular research group. In the last 3-5 years, due to significant efforts of global and regional CO2 monitoring networks (e.g., FluxNet, Ameriflux, Carbo-Europe, ICOS, etc.) and technological developments, the flux station methodology became fairly standardized and processing protocols became quite uniform [1]. A majority of current stations compute CO2 emission rates using the eddy covariance method, one of the most direct and defensible micrometeorological techniques [1]. Presently, over 600 such flux stations are in operation in over 120 countries, using permanent and mobile towers or moving platforms (e.g., automobiles, helicopters, and airplanes). Atmospheric monitoring of emission rates using such stations is now recognized as an effective method in regulatory and industrial applications, including carbon storage [2-8]. Emerging projects utilize flux stations to continuously monitor large areas before and after the injections, to locate and

  11. The Potential of CO2 Capture and Storage Technology in South Africa’s Coal-Fired Thermal Power Plants

    Directory of Open Access Journals (Sweden)

    Kelvin O. Yoro


    Full Text Available The global atmospheric concentration of anthropogenic gases, such as carbon dioxide, has increased substantially over the past few decades due to the high level of industrialization and urbanization that is occurring in developing countries, like South Africa. This has escalated the challenges of global warming. In South Africa, carbon capture and storage (CCS from coal-fired power plants is attracting increasing attention as an alternative approach towards the mitigation of carbon dioxide emission. Therefore, innovative strategies and process optimization of CCS systems is essential in order to improve the process efficiency of this technology in South Africa. This review assesses the potential of CCS as an alternative approach to reducing the amount CO2 emitted from the South African coal-fired power plants. It examines the various CCS processes that could be used for capturing the emitted CO2. Finally, it proposes the use of new adsorbents that could be incorporated towards the improvement of CCS technology.

  12. The CarbFix Pilot Project in Iceland - CO2 capture and mineral storage in basaltic rocks (United States)

    Sigurdardottir, H.; Sigfusson, B.; Aradottir, E. S.; Gunnlaugsson, E.; Gislason, S. R.; Alfredsson, H. A.; Broecker, W. S.; Matter, J. M.; Stute, M.; Oelkers, E.


    The overall objective of the CarbFix project is to develop and optimize a practical and cost-effective technology for capturing CO2 and storing it via in situ mineral carbonation in basaltic rocks, as well as to train young scientist to carry the corresponding knowledge into the future. The project consists of a field injection of CO2 charged water at the Hellisheidi geothermal power plant in SW Iceland, laboratory experiments, numerical reactive transport modeling, tracer tests, natural analogue and cost analysis. The CO2 injection site is situated about 3 km south of the Hellisheidi geothermal power plant. Reykjavik Energy operates the power plant, which currently produces 60,000 tons/year CO2 of magmatic origin. The produced geothermal gas mainly consists of CO2 and H2S. The two gases will be separated in a pilot gas treatment plant, and CO2 will be transported in a pipeline to the injection site. There, CO2 will be fully dissolved in 20 - 25°C water during injection at 25 - 30 bar pressure, resulting in a single fluid phase entering the storage formation, which consists of relatively fresh basaltic lavas. The CO2 charged water is reactive and will dissolve divalent cations from the rock, which will combine with the dissolved carbon to form solid thermodynamically stable carbonate minerals. The injection test is designed to inject 2200 tons of CO2 per year. In the past three years the CarbFix project has been addressing background fluid chemistries at the injection site and characterizing the target reservoir for the planned CO2 injection. Numerous groundwater samples have been collected and analysed. A monitoring and accounting plan has been developed, which integrates surface, subsurface and atmospheric monitoring. A weather station is operating at the injection site for continuous monitoring of atmospheric CO2 and to track all key parameters for the injection. Environmental authorities have granted licenses for the CO2 injection and the use of tracers, based

  13. A Review of Hazardous Chemical Species Associated with CO2 Capturefrom Coal-Fired Power Plants and Their Potential Fate in CO2 GeologicStorage

    Energy Technology Data Exchange (ETDEWEB)

    Apps, J.A.


    Conventional coal-burning power plants are major contributors of excess CO2 to the atmospheric inventory. Because such plants are stationary, they are particularly amenable to CO2 capture and disposal by deep injection into confined geologic formations. However, the energy penalty for CO2 separation and compression is steep, and could lead to a 30-40 percent reduction in useable power output. Integrated gas combined cycle (IGCC) plants are thermodynamically more efficient, i.e.,produce less CO2 for a given power output, and are more suitable for CO2 capture. Therefore, if CO2 capture and deep subsurface disposal were to be considered seriously, the preferred approach would be to build replacement IGCC plants with integrated CO2 capture, rather than retrofit existing conventional plants. Coal contains minor quantities of sulfur and nitrogen compounds, which are of concern, as their release into the atmosphere leads to the formation of urban ozone and acid rain, the destruction of stratospheric ozone, and global warming. Coal also contains many trace elements that are potentially hazardous to human health and the environment. During CO2 separation and capture, these constituents could inadvertently contaminate the separated CO2 and be co-injected. The concentrations and speciation of the co-injected contaminants would differ markedly, depending on whether CO2 is captured during the operation of a conventional or an IGCC plant, and the specific nature of the plant design and CO2 separation technology. However, regardless of plant design or separation procedures, most of the hazardous constituents effectively partition into the solid waste residue. This would lead to an approximately two order of magnitude reduction in contaminant concentration compared with that present in the coal. Potential exceptions are Hg in conventional plants, and Hg and possibly Cd, Mo and Pb in IGCC plants. CO2 capture and injection disposal could afford an opportunity to deliberately capture

  14. The Sulcis Storage Project: Status of the First Italian Initiative for Pilot-Scale Geological Sequestration of CO2 (United States)

    Plaisant, A.; Maggio, E.; Pettinau, A.


    The deep aquifer located at a depth of about 1000-1500 m within fractured carbonate in the Sulcis coal basin (South-West Sardinia, Italy) constitutes a potential reservoir to develop a pilot-scale CO2 storage site. The occurrence of several coal mines and the geology of the basin also provide favourable condition to install a permanent infrastructures where advanced CO2 storage technologies can be developed. Overall, the Sulcis project will allow to characterize the Sulcis coal basin (South West Sardinia, Italy) and to develop a permanent infrastructure (know-how, equipment, laboratories, etc.) for advanced international studies on CO2 storage. The research activities are structured in two different phases: (i) site characterization, including the construction of an underground and a fault laboratories and (ii) the installation of a test site for small-scale injection of CO2. In particular, the underground laboratory will host geochemical and geophysical experiments on rocks, taking advantages of the buried environment and the very well confined conditions in the galleries; in parallel, the fault laboratory will be constructed to study CO2 leakage phenomena in a selected fault. The project is currently ongoing and some preliminary results will be presented in this work as well as the structure of the project as a whole. More in detail, preliminary activities comprise: (i) geochemical monitoring; (ii) the minero-petrographycal, physical and geophysical characterization of the rock samples; (iii) the development of both static and dynamic geological models of the reservoir; (iv) the structural geology and fault analysis; (v) the assessment of natural seismicity through a monitoring network (vi) the re-processing and the analysis of the reflection seismic data. Future activities will comprise: (i) the drilling of shallow exploration wells near the faults; (ii) the construction of both the above mentioned laboratories; (iii) drilling of a deep exploration well (1,500 m

  15. Research and development of CO2 Capture and Storage Technologies in Fossil Fuel Power Plants

    Directory of Open Access Journals (Sweden)

    Lukáš Pilař


    Full Text Available This paper presents the results of a research project on the suitability of post-combustion CCS technology in the Czech Republic. It describes the ammonia CO2 separation method and its advantages and disadvantages. The paper evaluates its impact on the recent technology of a 250 MWe lignite coal fired power plant. The main result is a decrease in electric efficiency by 11 percentage points, a decrease in net electricity production by 62 MWe, and an increase in the amount of waste water. In addition, more consumables are needed.

  16. Determination of Priority Study Areas for Coupling CO2 Storage and CH4 Gas Hydrates Recovery in the Portuguese Offshore Area

    Directory of Open Access Journals (Sweden)

    Luís Bernardes


    Full Text Available Gas hydrates in sub-seabed sediments is an unexploited source of energy with estimated reserves larger than those of conventional oil. One of the methods for recovering methane from gas hydrates involves injection of Carbon Dioxide (CO2, causing the dissociation of methane and storing CO2. The occurrence of gas hydrates offshore Portugal is well known associated to mud volcanoes in the Gulf of Cadiz. This article presents a determination of the areas with conditions for the formation of biogenic gas hydrates in Portugal’s mainland geological continental margin and assesses their overlap with CO2 hydrates stability zones defined in previous studies. The gas hydrates stability areas are defined using a transfer function recently published by other authors and takes into account the sedimentation rate, the particulate organic carbon content and the thickness of the gas hydrate stability zone. An equilibrium equation for gas hydrates, function of temperature and pressure, was adjusted using non-linear regression and the maximum stability zone thickness was found to be 798 m. The gas hydrates inventory was conducted in a Geographic Information System (GIS environment and a full compaction scenario was adopted, with localized vertical flow assumed in the accrecionary wedge where mud volcanoes occur. Four areas where temperature and pressure conditions may exist for formation of gas hydrates were defined at an average of 60 km from Portugal’s mainland coastline. Two of those areas coincide with CO2 hydrates stability areas previously defined and should be the subject of further research to evaluate the occurrence of gas hydrate and the possibility of its recovery coupled with CO2 storage in sub-seabed sediments.

  17. Highly porous ionic rht metal-organic framework for H2 and CO2 storage and separation: A molecular simulation study

    KAUST Repository

    Babarao, Ravichandar


    The storage and separation of H2 and CO2 are investigated in a highly porous ionic rht metal-organic framework (rht-MOF) using molecular simulation. The rht-MOF possesses a cationic framework and charge-balancing extraframework NO3 - ions. Three types of unique open cages exist in the framework: rhombicuboctahedral, tetrahedral, and cuboctahedral cages. The NO3 - ions exhibit small mobility and are located at the windows connecting the tetrahedral and cuboctahedral cages. At low pressures, H2 adsorption occurs near the NO 3 - ions that act as preferential sites. With increasing pressure, H2 molecules occupy the tetrahedral and cuboctahedral cages and the intersection regions. The predicted isotherm of H2 at 77 K agrees well with the experimental data. The H2 capacity is estimated to be 2.4 wt % at 1 bar and 6.2 wt % at 50 bar, among the highest in reported MOFs. In a four-component mixture (15:75:5:5 CO2/H 2/CO/CH4) representing a typical effluent gas of H 2 production, the selectivity of CO2/H2 in rht-MOF decreases slightly with increasing pressure, then increases because of cooperative interactions, and finally decreases as a consequence of entropy effect. By comparing three ionic MOFs (rht-MOF, soc-MOF, and rho-ZMOF), we find that the selectivity increases with increasing charge density or decreasing free volume. In the presence of a trace amount of H2O, the interactions between CO2 and NO3 - ions are significantly shielded by H2O; consequently, the selectivity of CO 2/H2 decreases substantially. © 2010 American Chemical Society.

  18. 'I reject your reality and substitute my own'. Why more knowledge about CO2 storage hardly improves public attitudes

    Energy Technology Data Exchange (ETDEWEB)

    Brunsting, S.; De Best-Waldhober, M. [ECN Policy Studies, Amsterdam (Netherlands); Terwel, B.W. [Leiden University, Department of Social and Organizational Psychology, Leiden (Netherlands)


    Lack of societal acceptance of energy (transition) technologies is often attributed to a lack of knowledge among the public. The underlying assumption is that more knowledge improves attitudes about a technology. This assumption will be tested in this paper by examining the influence of the scores on a CCS Knowledge Test on attitudes towards CO2 capture and storage (CCS). Furthermore the paper will examine the influence of perceptions of CCS (ideas that cannot be deemed 'true' or 'false') on attitude towards CCS and will analyse how knowledge and perceptions jointly influence attitude as well as in interaction. Implications of the results for communication about CCS are discussed.

  19. Tri-reforming as a process of CO2 utilization and a novel concept of energy storage in chemical products

    Directory of Open Access Journals (Sweden)

    Świrk Katarzyna


    In this paper two scenarios for methane tri-reforming implementation are discussed: (i Tri-reforming as a effective way for chemical CO2 utilization, without the separation of carbon dioxide from flue gases from fossil fuel-fired power stations, and (ii dry reforming of methane improved by the addition of water and oxygen, which may be applied as a chemical energy storage process. The literature on the subject of trireforming is shortly reviewed, including thermodynamics of the process, the possible conversions of methane and carbon dioxide, and proposed catalysts, both studied in tri-reforming, and in single processes (SRM, DRM and POM.

  20. A Comparison of national CCS strategies for Northwest Europe, with a focus on the potential of common CO2 storage at the Utsira formation

    DEFF Research Database (Denmark)

    Ramirez, Andrea; Hoefnagels, Ric; van den Broek, Machteld


    Mega structures for CO2 storage, such as the Utsira formation in the North Sea, could theoretically supply CO2 storage capacity for several countries for a period of several decades. Their use could increase the cost-effectiveness of CCS in a region while minimizing opposition from the public to CO......2 storage. However, this will not only depend on their potential available capacity to store CO2 flows but also on the cost effectiveness of such an option within national portfolios of mitigation measures. This article shows key results of a research project aiming to assess the potentials...... and costs of storing CO2 in the Utsira formation for the time period 2015–2050. Countries included in the analysis are Denmark, Germany, Norway, the Netherlands and the United Kingdom. The starting point of the analysis are the national MARKAL and TIMES models developed for each country together with the 27...

  1. Have We Overestimated Saline Aquifer CO2 Storage Capacities? Avons-nous surestimé les capacités de stockage de CO2 des aquifères salins ?

    Directory of Open Access Journals (Sweden)

    Thibeau S.


    Full Text Available During future, large scale CO2 geological storage in saline aquifers, fluid pressure is expected to rise as a consequence of CO2 injection, but the pressure build up will have to stay below specified values to ensure a safe and long term containment of the CO2 in the storage site. The pressure build up is the result of two different effects. The first effect is a local overpressure around the injectors, which is due to the high CO2 velocities around the injectors, and which can be mitigated by adding CO2 injectors. The second effect is a regional scale pressure build up that will take place if the storage aquifer is closed or if the formation water that flows away from the pressurised area is not large enough to compensate volumetrically the CO2 injection. This second effect cannot be mitigated by adding additional injectors. In the first section of this paper, we review some major global and regional assessments of CO2 storage capacities in deep saline aquifers, in term of mass and storage efficiency. These storage capacities are primarily based on a volumetric approach: storage capacity is the volumetric sum of the CO2 that can be stored through various trapping mechanisms. We then discuss in Section 2 storage efficiencies derived from a pressure build up approach, as stated in the CO2STORE final report (Chadwick A. et al. (eds (2008 Best Practice for the Storage of CO2 in Saline Aquifers, Observations and Guidelines from the SACS and CO2STORE Projects, Keyworth, Nottingham, BGS Occasional Publication No. 14 and detailed by Van der Meer and Egberts (van der Meer L.G.H., Egberts P.J.P. (2008 A General Method for Calculating Subsurface CO2 Storage Capacity, OTC Paper 19309, presented at the OTC Conference held in Houston, Texas, USA, 5-8 May. A quantitative range of such storage efficiency is presented, based on a review of orders of magnitudes of pore and water compressibilities and allowable pressure increase. To illustrate the relevance of

  2. Brine/CO2 Interfacial Properties and Effects on CO2 Storage in Deep Saline Aquifers Propriétés interfaciales saumure/CO2 et effets sur le stockage du CO2 dans des aquifères salins profonds

    Directory of Open Access Journals (Sweden)

    Chalbaud C.


    Full Text Available It has been long recognized that interfacial interactions (interfacial tension, wettability, capillarity and interfacial mass transfer govern fluid distribution and behaviour in porous media. Therefore the interfacial interactions between CO2, brine and reservoir oil and/or gas have an important influence on the effectiveness of any CO2 storage operation. There is a lack of experimental data related to interfacial properties for all the geological storage options (oil & gas reservoirs, coalbeds, deep saline aquifers. In the case of deep saline aquifers, there is a gap in data and knowledge of brine-CO2 interfacial properties at storage conditions. More specifically, experimental interfacial tension values and experimental tests in porous media are necessary to better understand the wettability evolution as a function of thermodynamic conditions and it’s effects on fluid flow in the porous media. In this paper, a complete set of experimental values of brine-CO2 Interfaciale Tension (IFT at pressure, temperature and salt concentration conditions representative of those of a CO2 storage operation. A correlation is derived from experimental data published in a companion paper [Chalbaud C., Robin M., Lombard J.-M., Egermann P., Bertin H. (2009 Interfacial Tension Measurements and Wettability Evaluation for Geological CO2 Storage, Adv. Water Resour. 32, 1, 1-109] to model IFT values. This paper pays particular attention to coreflooding experiments showing that the CO2 partially wets the surface in a Intermediate-Wet (IW or Oil-Wet (OW limestone rock. This wetting behavior of CO2 is coherent with observations at the pore scale in glass micromodels and presents a negative impact on the storage capacity of a given site. Il est admis depuis longtemps que les propriétés interfaciales (tension interfaciale, mouillabilité, capillarité et transfert de masse régissent la distribution et le comportement des fluides au sein des milieux poreux. Par cons

  3. Assessing the short-term and long-term integrity of top seals in feasibility studies of geological CO2 storage

    NARCIS (Netherlands)

    Orlic, B.; Heege J.H. ter; Wassing, B.


    The geomechanical effects of past hydrocarbon production and subsequent CO2 injection in depleted gas reservoirs were evaluated as a part of several recently accomplished feasibility studies of CO2 storage in the Netherlands. The objectives of geomechanical studies were to assess the mechanical

  4. Hierarchical Mesoporous 3D Flower-like CuCo2O4/NF for High-Performance Electrochemical Energy Storage

    National Research Council Canada - National Science Library

    Jadhav, Harsharaj S; Pawar, Sambhaji M; Jadhav, Arvind H; Thorat, Gaurav M; Seo, Jeong Gil


    Ternary spinel CuCo2O4 nanostructure clenches great potential as high-performance electrode material for next-generation energy storage systems because of its higher electrical conductivity and electrochemical activity...

  5. Southeast Offshore Storage Resource Assessment (SOSRA): Evaluation of CO2 Storage Potential on the Continental Shelf from North Carolina to Florida (United States)

    Knapp, J. H.; Knapp, C. C.; Brantley, D.; Lakshmi, V.; Howard, S.


    The Southeast Offshore Storage Resource Assessment (SOSRA) project is part of a major new program, funded by the U.S. Department of Energy for the next two and a half years, to evaluate the Atlantic and Gulf of Mexico offshore margins of the United States for geologic storage capacity of CO2. Collaborating organizations include the Southern States Energy Board, Virginia Polytechnic Institute, University of South Carolina, Oklahoma State University, Virginia Department of Mines, Minerals, and Energy, South Carolina Geological Survey, and Geological Survey of Alabama. Team members from South Carolina are focused on the Atlantic offshore, from North Carolina to Florida. Geologic sequestration of CO2 is a major research focus globally, and requires robust knowledge of the porosity and permeability distribution in upper crustal sediments. Using legacy seismic reflection, refraction, and well data from a previous phase of offshore petroleum exploration on the Atlantic margin, we are analyzing the rock physics characteristics of the offshore Mesozoic and Cenozoic stratigraphy on a regional scale from North Carolina to Florida. Major features of the margin include the Carolina Trough, the Southeast Georgia Embayment, the Blake Plateau basin, and the Blake Outer Ridge. Previous studies indicate sediment accumulations on this margin may be as thick as 12-15 km. The study will apply a diverse suite of data analysis techniques designed to meet the goal of predicting storage capacity to within ±30%. Synthetic seismograms and checkshot surveys will be used to tie well and seismic data. Seismic interpretation and geophysical log analysis will employ leading-edge software technology and state-of-the art techniques for stratigraphic and structural interpretation and the definition of storage units and their physical and chemical properties. This approach will result in a robust characterization of offshore CO2 storage opportunities, as well as a volumetric analysis that is

  6. An estimation of traffic related CO2 emissions from motor vehicles in the capital city of, Iran

    Directory of Open Access Journals (Sweden)

    Kakouei Aliakbar


    Full Text Available Abstract Vehicle exhaust is a major source of anthropogenic carbon dioxide (CO2 in metropolitan cities. Popular community mode (buses and taxies and about 2.4 million private cars are the main emission sources of air pollution in Tehran. A case survey has conducted to measure CO2 in four popular vehicles, bus, taxi, private car and motorcycle, which moved in the city with respectively 7800, 82358, 560000 and 2.4 million per day in 2012. Results indicated that the contribution of CO2 emissions increased in the following order: private car, motorcycle, bus and taxi. The overall average for the contribution of CO2 emissions in the private car, motorcycle, bus, and taxi were 26372, 1648, 1433 and 374 tons per day, respectively. Our results also showed that the urban transport operation consume an estimated 178 and 4224 million liter diesel and petrol per year, respectively, that have released about 10 million tons of CO2. The average contribution of CO2 emissions of private cars in Tehran was higher (88% than other vehicles. It was concluded that high volume of traffic, transport consumption of fossil fuels and shortage of adequate public transport system are responsible for the high CO2 level in environment in Tehran. Thus, it is to be expected that CO2 as a greenhouse gas has risen in Tehran more than ever in the following years and this would be a matter of concern for the authorities to have a comprehensive plan to mitigate this phenomena.

  7. Leakage of CO2 from sub-seafloor CO2 storage sites to the seabed; Impacts on sediment microorganisms and geochemical parameters during in situ and laboratory leakage experiments (United States)

    Reigstad, L. J.; Hannisdal, B.; Hoffmann, F. U.; Sweetman, A. K.; Baumberger, T.; Eickmann, B.; Røy, H.; Thorseth, I. H.; Pedersen, R. B.


    Since 1996, 14 million tons of CO2 extracted from natural gas have been injected into the Utsira Formation, a saline aquifer at ~1000 m depth in the North Sea. The injected CO2 covers today an area of 4 x 2 km2. At present, there are three international treaties protecting the oceans, and all three allow CO2 storage in sub-seabed geological formations. One of these, the EU Directive 2009/31, states that monitoring must take place before, during and after CO2 storage in order to detect leakage of CO2 and significant adverse effects on the surrounding environment. However, few environmental studies have investigated the potential impacts of a CO2 leakage on the microbial life and geochemical conditions in seafloor sediment. To remedy this, we performed two experiments with abrupt CO2 acidification on the top 10 cm of the seafloor close to the North Sea storage site: 1) One laboratory CO2 acidification experiment on undisturbed sediment cores from the seafloor overlying the CO2 storage site (80 m water depth). The continuous flow of CO2 acidified seawater (pH 6.4) with 20 000 μatm pCO2 over the cores lasted for 1.5 months with sediment core terminations at regular intervals. 2) In situ CO2 acidification experiments carried out on the seafloor at 350 m water depth, with life span of 40 hours and exposure to 20 000 μatm pCO2. Both experiments showed increased O2 consumption in the water overlying the CO2 acidified sediment relative to the control sediment, indicating a rise in metabolic activity due to the treatment. After about 12 hours of acidification and throughout the laboratory experimental period, an increase in macrofauna burial activity could be seen, with dead/dying macrofauna appearing on the sediment surface. The pyrosequencing amplicon dataset obtained after bacterial and archaeal 16S rRNA amplification (RNA level) was subjected to multivariate analyses (PCA, NMDS), revealing changes in the active community on phylum, class and OTU levels. Changes were

  8. Calculation of pressure- and migration-constrained dynamic CO2 storage capacity of the North Sea Forties and Nelson dome structures


    Babaei, Masoud; Govindan, Rajesh; Korre, Anna; Shi, Ji-Quan; Durucan, Sevket; Quinn, Martyn


    This paper presents a numerical simulation study of CO2 injection into the Forties and Nelson dome structures in the North Sea. The study assumes that these structures are fully depleted of their remaining hydrocarbon and brine has replaced their pore space, and therefore the structures can be treated as saline aquifers. Under this assumption, the objective is to calculate the dynamic CO2 storage capacity of the Forties and Nelson structures and design an injection scenario to enhance storage...

  9. CO2 capture and storage (Breaking the Climate Deadlock Briefing Paper)

    Energy Technology Data Exchange (ETDEWEB)

    Bakker, S.J.A.; De Coninck, H.C.; Groenenberg, H. [ECN Policy Studies, Petten (Netherlands)


    This paper explores opportunities for Carbon Capture and Storage (CCS) technologies to abate carbon dioxide under anticipated conditions of continued fossil fuel use, and sets out the need for early demonstration of the technologies to overcome barriers to their deployment. The paper covers: CCS technology and its role in global mitigation scenarios; The maturity of the various components of CCS technology; Costs and required investment; Policy issues and barriers to be overcome.

  10. The Ohio River Valley CO2 Storage Project AEP Mountaineer Plan, West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Neeraj Gupta


    This report includes an evaluation of deep rock formations with the objective of providing practical maps, data, and some of the issues considered for carbon dioxide (CO{sub 2}) storage projects in the Ohio River Valley. Injection and storage of CO{sub 2} into deep rock formations represents a feasible option for reducing greenhouse gas emissions from coal-burning power plants concentrated along the Ohio River Valley area. This study is sponsored by the U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL), American Electric Power (AEP), BP, Ohio Coal Development Office, Schlumberger, and Battelle along with its Pacific Northwest Division. An extensive program of drilling, sampling, and testing of a deep well combined with a seismic survey was used to characterize the local and regional geologic features at AEP's 1300-megawatt (MW) Mountaineer Power Plant. Site characterization information has been used as part of a systematic design feasibility assessment for a first-of-a-kind integrated capture and storage facility at an existing coal-fired power plant in the Ohio River Valley region--an area with a large concentration of power plants and other emission sources. Subsurface characterization data have been used for reservoir simulations and to support the review of the issues relating to injection, monitoring, strategy, risk assessment, and regulatory permitting. The high-sulfur coal samples from the region have been tested in a capture test facility to evaluate and optimize basic design for a small-scale capture system and eventually to prepare a detailed design for a capture, local transport, and injection facility. The Ohio River Valley CO{sub 2} Storage Project was conducted in phases with the ultimate objectives of demonstrating both the technical aspects of CO{sub 2} storage and the testing, logistical, regulatory, and outreach issues related to conducting such a project at a large point source under realistic constraints. The site

  11. Low-dimensional models for the estimation of anthropogenic CO2 emissions from atmospheric observations (United States)

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


    The estimation of anthropogenic fossil fuel emissions using atmospheric observations of CO2 has recently attracted increasing interest due to its relevance to monitoring of CO2 mitigation treaties and programs. To date, techniques to perform large-scale inversions had primarily been developed within the context of understanding biospheric and oceanic fluxes. Such fluxes tend to vary relatively smoothly in space and time, making it possible to use multiGaussian models to parameterize and regularize such inversions, predicated on limited measurements of CO2 concentrations. However, the spatial distribution of anthropogenic emissions is non-stationary and multiscale, and therefore makes the use of multiGaussians models less suitable. Thus, a need exists to identify how anthropogenic emissions may be represented in a low-dimensional manner (i.e., with few parameters), for use in top-down estimation. Certain aspects of the spatial extent of anthropogenic emissions can be represented using easily measurable proxies such as nightlights, population density and GDP; in fact, fossil fuel inventories regularly use them to disaggregate regional emission budgets to finer spatial resolutions. However, such proxies can also be used to construct a priori models for anthropogenic emissions, which can then be updated, with data, through inverse modeling. In this presentation, we compare 3 low-dimensional parameterizations to characterize anthropogenic sources. The models are derived from images of nightlights over the continental USA, but adopt different arguments to achieve their dimensionality reduction. In the first model, we threshold nightlights and fit bivariate Gaussian kernels over clusters to represent emission sources; the emission field is modeled as a weighted sum of the kernels. The second approach models emissions as a weighted superposition of a filtered nightlight-distribution and a multiresolution defect, modeled with Haar wavelet. The nightlight-based methods

  12. An integrated petrophysical-geophysical approach for the characterization of a potential caprock-reservoir system for CO2 storage. (United States)

    Fais, Silvana; Ligas, Paola; Cuccuru, Francesco; Casula, Giuseppe; Giovanna Bianchi, Maria; Maggio, Enrico; Plaisant, Alberto; Pettinau, Alberto


    The selection of a CO2 geologic storage site requires the choice of a study site suitable for the characterization in order to create a robust experimental database especially regarding the spatial petrophysical heterogeneities and elasto-mechanical properties of the rocks that make up a potential caprock-reservoir system. In our study the petrophysical and elasto-mechanical characterization began in a previously well drilled area in the northern part of the Sulcis coal basin (Nuraxi Figus area - SW Sardinia - Italy) where crucial geologic data were recovered from high-quality samples from stratigraphic wells and from mining galleries. The basin represents one of the most important Italian carbon reserves characterized by a great mining potential. In the study area, the Middle Eocene - Lower Oligocene Cixerri Fm. made up of terrigeneous continental rocks and the Upper Thanetian - Lower Ypresian Miliolitico Carbonate Complex in the Sulcis coal basin have been identified respectively as potential caprock and reservoir for CO2 storage. Petrophysical and geophysical investigations were carried out by a great number of laboratory tests on the core samples and in situ measurements on a mining gallery in order to characterize the potential caprock-reservoir system and to substantially reduce geologic uncertainty in the storage site characterization and in the geological and numerical modelling for the evaluation of CO2 storage capacity. In order to better define the spatial distribution of the petrophysical heterogeneity, the seismic responses from the caprock-reservoir system formations were also analysed and correlated with the petrophysical and elasto-mechanical properties In a second step of this work, we also analysed the tectonic stability of the study area by the integrated application of remote-sensing monitoring spatial geodetic techniques. In particular, the global positioning system (GPS) and interferometric synthetic aperture radar (inSAR) were considered

  13. Mathematical models as tools for probing long-term safety of CO2 storage

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, Karsten; Birkholzer, Jens; Zhou, Quanlin


    Subsurface reservoirs being considered for storing CO{sub 2} include saline aquifers, oil and gas reservoirs, and unmineable coal seams (Baines and Worden, 2004; IPCC, 2005). By far the greatest storage capacity is in saline aquifers (Dooley et al., 2004), and our discussion will focus primarily on CO{sub 2} storage in saline formations. Most issues for safety and security of CO{sub 2} storage arise from the fact that, at typical temperature and pressure conditions encountered in terrestrial crust, CO{sub 2} is less dense than aqueous fluids. Accordingly, CO{sub 2} will experience an upward buoyancy force in most subsurface environments, and will tend to migrate upwards whenever (sub-)vertical permeable pathways are available, such as fracture zones, faults, or improperly abandoned wells (Bachu, 2008; Pruess, 2008a, b; Tsang et al., 2008). CO{sub 2} injection will increase fluid pressures in the target formation, thereby altering effective stress distributions, and potentially triggering movement along fractures and faults that could increase their permeability and reduce the effectiveness of a caprock in containing CO{sub 2} (Rutqvist et al., 2008; Chiaramonte et al., 2008). Induced seismicity as a consequence of fluid injection is also a concern (Healy et al., 1968; Raleigh et al., 1976; Majer et al., 2007). Dissolution of CO{sub 2} in the aqueous phase generates carbonic acid, which may induce chemical corrosion (dissolution) of minerals with associated increase in formation porosity and permeability, and may also mediate sequestration of CO{sub 2} as solid carbonate (Gaus et al., 2008). Chemical dissolution of caprock minerals could promote leakage of CO{sub 2} from a storage reservoir (Gherardi et al., 2007). Chemical dissolution and geomechanical effects could reinforce one another in compromising CO{sub 2} containment. Additional issues arise from the potential of CO{sub 2} to mobilize hazardous chemical species (Kharaka et al., 2006), and from migration of

  14. The potential of using remote sensing data to estimate air-sea CO2 exchange in the Baltic Sea (United States)

    Parard, Gaëlle; Rutgersson, Anna; Parampil, Sindu Raj; Alexandre Charantonis, Anastase


    In this article, we present the first climatological map of air-sea CO2 flux over the Baltic Sea based on remote sensing data: estimates of pCO2 derived from satellite imaging using self-organizing map classifications along with class-specific linear regressions (SOMLO methodology) and remotely sensed wind estimates. The estimates have a spatial resolution of 4 km both in latitude and longitude and a monthly temporal resolution from 1998 to 2011. The CO2 fluxes are estimated using two types of wind products, i.e. reanalysis winds and satellite wind products, the higher-resolution wind product generally leading to higher-amplitude flux estimations. Furthermore, the CO2 fluxes were also estimated using two methods: the method of Wanninkhof et al. (2013) and the method of Rutgersson and Smedman (2009). The seasonal variation in fluxes reflects the seasonal variation in pCO2 unvaryingly over the whole Baltic Sea, with high winter CO2 emissions and high pCO2 uptakes. All basins act as a source for the atmosphere, with a higher degree of emission in the southern regions (mean source of 1.6 mmol m-2 d-1 for the South Basin and 0.9 for the Central Basin) than in the northern regions (mean source of 0.1 mmol m-2 d-1) and the coastal areas act as a larger sink (annual uptake of -4.2 mmol m-2 d-1) than does the open sea (-4 mmol m-2 d-1). In its entirety, the Baltic Sea acts as a small source of 1.2 mmol m-2 d-1 on average and this annual uptake has increased from 1998 to 2012.

  15. Estimation of air-sea CO2 flux in the coastal waters of Visakhapatnam

    Digital Repository Service at National Institute of Oceanography (India)

    Latha, T.P.; Rao, K.H.; Sarma, V.V.S.S.; Seetaram, P.; Choudhury, S.B.; Nagamani, P.V.; Dutt, B.S.; Dhadwal, V.K.; Manna, S.

    radiation, humidity, wind speed, direction and gust were measured using AWS (Watch Dog, 2000 series) instrument which was mounted on the top of the boat. The atmospheric CO2 was measured using Li-COR 840A. The partial pressure of carbon dioxide (pCO2...

  16. Confining Properties of Carbonated Dogger Caprocks (Parisian Basin for CO2 Storage Purpose Propriétés de confinement des couvertures du Dogger carbonaté (Bassin de Paris dans l’optique du stockage de CO2

    Directory of Open Access Journals (Sweden)

    Carles P.


    Full Text Available The Géocarbone-Intégrité project, funded by ANR (Agence Nationale de la Recherche from 2006 to 2008, has the overall objective of gaining knowledge and technology to predict storage integrity and safety for long term geological CO2 sequestration. The aim of this study (Sect. 1 and 2 of the project is to evaluate the sealing capacities of the carbonated Dogger caprocks located on top of the reservoirs where CO2 could be injected for storage purposes in the Parisian Basin. A petrographic analysis is done on 3 different cores from geological formations of the “Comblanchien and Dalle Nacrée” tight carbonates facies. At the same time, a petrophysical study of these facies is performed. Porosity, pore size distribution and permeability are determined using special devices adapted to low permeability and tight rocks ( Le projet Géocarbone-Intégrité, financé par l’Agence Nationale de la Recherche (ANR de 2006 à 2008, vise à développer les connaissances et les techniques nécessaires à la prévision de l’efficacité et la sécurité du confinement sur le long terme des stockages géologiques de CO2. La première tâche a été de caractériser à l’échelle pétrographique, les faciès carbonatés du sommet du Dogger appartenant aux formations des Calcaires du Comblanchien et de la Dalle Nacrée, situées immédiatement au-dessus des niveaux réservoirs retenus comme potentiels sites de stockage. Une étude pétrophysique précise des faciès de couvertures potentielles est réalisée. La porosité, la distribution de taille de pores et la perméabilité sont déterminées en utilisant des méthodes adaptées à des milieux très peu perméables (< 10 microDarcy. Les perméabilités sont mesurées à l’azote, à l’hélium et à la saumure sous pression de confinement avec la méthode stationnaire et la méthode transitoire. Les porosités sont faibles et varient de 2 à 9 % suivant le faciès, et les perméabilités en

  17. CLEAN - Large-Scale CO2 Storage for Enhanced Gas Recovery in a depleted German Gasfield (United States)

    Kuehn, M.; Förster, A.; Grossmann, J.; Meyer, R.; Pilz, P.; Reinicke, K.; Schaefer, D.; Tesmer, M.; Wendel, H.


    ) baseline stress conditions, (10) monitoring set-up comprising reservoir, cap rock and shallow aquifer compartments as well as the unsaturated zone and ground surface, (11) implementation of monitoring for the purpose of determining natural variations for the parameters, and (12) assessment of various methods with regard to temporal and spatial scales for the parameters recorded. The joint research project developed technologies and methods to be used for a CO2 based EGR within the Altmark. Furthermore, this work is a major step forward understanding the behavior of CO2 injected into a depleted gas field. The findings support the definition of national and international standards, the development of best practice guidelines and built up expertise for this new technology. Acknowledgement: CLEAN is part of the geoscientific R&D program "GEOTECHNOLOGIEN" funded by the German Federal Ministry of Education and Research (BMBF) and GDF SUEZ.

  18. A comparative approach for modeling of CO2 storage capacity and associated pressure response - analysis of data from South Scania site, Sweden (United States)

    Tian, Liang; Yang, Zhibing; Jung, Byeongju; Joodaki, Saba; Niemi, Auli; Fagerlund, Fritjof; Erlström, Mikael


    Comprehensive modeling with models of varying level of accuracy can give valuable information for the appraisal of CO2 storage potential and the assessment of risks for a given site. Here, we present a comparative modeling approach/workflow where a sequence of mathematical models of different levels of complexity are applied. These models span from semi-analytical solution to three-dimensional (3D) numerical simulator. The Scania Site, southwest Sweden where the geological model was developed within the MUSTANG project activities is selected for an example study. Initially, a semi-analytical approach is used to investigate pressure increase induced by CO2 injection so as to determine a viable injection strategy (including injection rate and number of injection wells) and parameter sensitivity. The result is then used as a starting point in subsequent numerical simulations with TOUGH2/ECO2N for 2D and 3D simulations. At the same time a simplified numerical model with the vertical equilibrium (VE) approach is also implemented. A systematic comparison is done between the different methods in terms of pressure response. CO2 spreading during both the injection and post-injection phase is also carefully compared between the 2D, VE and 3D numerical simulations. Through these comparisons we can thus identify a model with the appropriate level of complexity according to the objectives of the modeling study. Given the data available, we show an effective modeling strategy in achieving order-of-magnitude estimates on the behavior of the identified CO2 traps during and after the injection.

  19. Simulation of the crosshole ERT monitoring of the CO2 migration at the Research Laboratory on Geological Storage of CO2 in Hontomín (Burgos, Spain): assessing its feasibility and the optimal configuration (United States)

    Vilamajó, Eloi; Bellmunt, Fabian; Queralt, Pilar; Marcuello, Álex; Ledo, Juanjo


    The Research Laboratory on Geological Storage of CO2 located in Hontomín (Burgos, Spain) is a multidisciplinary Technological Demonstration Plant oriented to test the geological storage of carbon dioxide in an onshore saline reservoir. Due to its academic orientation, it will provide a wide set of data obtained with complementary geophysical techniques. In order to allow the integration of the respective results, several geophysical methods will be used on the monitoring process of the storage of CO2 into a deep saline aquifer. The resistivity of the storage formation will be one of the geophysical properties most affected by the replacement of the conductive brine by resistive carbon dioxide. As the electrical and electromagnetic methods are the techniques most sensitive to such change, their use on the monitoring process of the Hontomín TDP will provide important insights on the migration of CO2. The current work is integrated in the electric and electromagnetic monitoring of the CO2 storage at Hontomín, where two boreholes (injection and monitoring) will be drilled beneath the injection depth. A set of electrodes is planned to be installed at the two wells allowing advantageous experiments in order to determine the resistivity variation into the reservoir. Crosshole ERT and CSEM experiments will be carried out previously to the injection of carbon dioxide and repeated systematically once the storage has started. The feasibility of the crosshole ERT monitoring is evaluated in the current work. Realistic pre-injection and post-injection experiments have been modeled to assess the potentiality and benefits of the crosshole ERT in order to monitor the stored CO2. A geoelectrical model obtained from previous characterization works has been used to describe the geoelectrical structure. The metallic casings planned to be installed at the two wells are considered in the simulations, given their possible effect on the experiments. Sets of synthetic data are generated

  20. Leakage Risk Assessment for a Potential CO2 Storage Project in Saskatchewan, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Houseworth, J.E.; Oldenburg, C.M.; Mazzoldi, A.; Gupta, A.K.; Nicot, J.-P.; Bryant, S.L.


    A CO{sub 2} sequestration project is being considered to (1) capture CO{sub 2} emissions from the Consumers Cooperative Refineries Limited at Regina, Saskatchewan and (2) geologically sequester the captured CO{sub 2} locally in a deep saline aquifer. This project is a collaboration of several industrial and governmental organizations, including the Petroleum Technology Research Centre (PTRC), Sustainable Development Technology Canada (SDTC), SaskEnvironment Go Green Fund, SaskPower, CCRL, Schlumberger Carbon Services, and Enbridge. The project objective is to sequester 600 tonnes CO{sub 2}/day. Injection is planned to start in 2012 or 2013 for a period of 25 years for a total storage of approximately 5.5 million tonnes CO{sub 2}. This report presents an assessment of the leakage risk of the proposed project using a methodology known as the Certification Framework (CF). The CF is used for evaluating CO{sub 2} leakage risk associated with geologic carbon sequestration (GCS), as well as brine leakage risk owing to displacement and pressurization of brine by the injected CO{sub 2}. We follow the CF methodology by defining the entities (so-called Compartments) that could be impacted by CO{sub 2} leakage, the CO{sub 2} storage region, the potential for leakage along well and fault pathways, and the consequences of such leakage. An understanding of the likelihood and consequences of leakage forms the basis for understanding CO{sub 2} leakage risk, and forms the basis for recommendations of additional data collection and analysis to increase confidence in the risk assessment.

  1. Modeling basin- and plume-scale processes of CO2 storage for full-scale deployment

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Q.; Birkholzer, J.T.; Mehnert, E.; Lin, Y.-F.; Zhang, K.


    Integrated modeling of basin- and plume-scale processes induced by full-scale deployment of CO{sub 2} storage was applied to the Mt. Simon Aquifer in the Illinois Basin. A three-dimensional mesh was generated with local refinement around 20 injection sites, with approximately 30 km spacing. A total annual injection rate of 100 Mt CO{sub 2} over 50 years was used. The CO{sub 2}-brine flow at the plume scale and the single-phase flow at the basin scale were simulated. Simulation results show the overall shape of a CO{sub 2} plume consisting of a typical gravity-override subplume in the bottom injection zone of high injectivity and a pyramid-shaped subplume in the overlying multilayered Mt. Simon, indicating the important role of a secondary seal with relatively low-permeability and high-entry capillary pressure. The secondary-seal effect is manifested by retarded upward CO{sub 2} migration as a result of multiple secondary seals, coupled with lateral preferential CO{sub 2} viscous fingering through high-permeability layers. The plume width varies from 9.0 to 13.5 km at 200 years, indicating the slow CO{sub 2} migration and no plume interference between storage sites. On the basin scale, pressure perturbations propagate quickly away from injection centers, interfere after less than 1 year, and eventually reach basin margins. The simulated pressure buildup of 35 bar in the injection area is not expected to affect caprock geomechanical integrity. Moderate pressure buildup is observed in Mt. Simon in northern Illinois. However, its impact on groundwater resources is less than the hydraulic drawdown induced by long-term extensive pumping from overlying freshwater aquifers.

  2. Preliminary Safety and Risk HSE Assessment. Application to the Potential Locations of a CO2 Geological Storage Pilot; Evaluación Preliminar de la Seguridad y de los Riesgos HSE. Aplicación a las Potenciales Ubicaciones de una Planta Piloto de Almacenamiento Geológico de CO2.

    Energy Technology Data Exchange (ETDEWEB)

    Recreo, F.; Eguilior, S.; Ruiz, C.; Lomba, L.; Hurtado, A.


    The location of a site safe and able to sequester CO2 for long periods of time is essential to gain public acceptance. This requires a long-term safety assessment developed in a robust and reliable framework. Site selection is the first step and requires specific research. This paper describes the application of the Selection and Classification Method of Geological Formations (SCF) developed to assess the potential of geological formations to CO2 storage. This assessment is based in the analysis of risks to Health, Safety and Environment (HSE) derived from potential CO2 leakage. Comparisons of the results obtained from a number of potential sites can help to select the best candidate for CO2 injection. The potential impact will be related to three key potential features of CO2 geological storage: the potential of the target geological formation for long term CO2 containment; the potential for secondary containment on containment failure of the target formation; and the site's potential to mitigate and/or disperse CO2 leakage if the primary and secondary containments fail. The methodology assesses each of these three characteristics through an analysis and assessment of properties of certain attributes of them. Uncertainty will remain as an input and output value of the methodology due to the usual lack of data in most site selection processes. The global uncertainty reports on the trust on the knowledge of the site characteristics. Therefore, the methodology enables comparing sites taking into account both the HSE risk expectation and the estimation of the quality of knowledge concerning such risk. The objective is to contribute to the selection of potential sites for a CO2 injection pilot plant in the Iberian Peninsula from the perspective of Safety and Risk Analysis.

  3. Estimation of CO2-Equivalent Emission under the Copper Fire Refining Process (United States)

    Chesnokov, Yu N.; Lisienko, V. G.; Holod, S. I.; Anufriev, V. P.; Lapteva, A. V.


    Non-ferrous metallurgy is one of the most energy-consuming and carbon-emissive sectors of industry. This is due to the fact that the volume of greenhouse gas (GHG) emissions is stipulated by energy consumption. Uralelectromed is a city-forming enterprise of the Verkhnyaya Pyshma. The situation is similar other cities of the old industrial regions of the Russian Federation (Krasnouralsk, Verkhnaya Salda, Karabash, etc.) Verkhnyaya Pyshma has many characteristics of “a clever city”. It can be compared to Hamburg where blister copper is being produced at the center of the city at a copper smelting plant Aurubis. Following the example of such ecologically clean country as Germany and in order to assess how modern energy-efficient low-carbon technologies can provide a favorable habitat, and an acceptable level of carbon footprint, the authors estimated the level of greenhouse gas, i.e., carbon dioxide emission produced by the Uralelectromed. The emission of greenhouse gas -carbon dioxide in the process of fire refining of blister copper has been calculated. The anode melting process consists of several stages where the most important ones are melting of charge, oxidation, and copper melt reduction. Calculations are based on taking into account the mass of burnt carbon of natural gas and the thermal dissociation of fuel oil. It implies that a complete combustion of carbon takes place. The specific value of carbon dioxide emission of the copper refining process is averaged 181 kg CO2 per 1 ton of anode copper.

  4. How to Characterize a Potential Site for CO2 Storage with Sparse Data Coverage – a Danish Onshore Site Case

    Directory of Open Access Journals (Sweden)

    Nielsen Carsten Møller


    Full Text Available The paper demonstrates how a potential site for CO2 storage can be evaluated up to a sufficient level of characterization for compiling a storage permit application, even if the site is only sparsely explored. The focus of the paper is on a risk driven characterization procedure. In the initial state of a site characterization process with sparse data coverage, the regional geological and stratigraphic understanding of the area of interest can help strengthen a first model construction for predictive modeling. Static and dynamic modeling in combination with a comprehensive risk assessment can guide the different elements needed to be evaluated for fulfilling a permit application. Several essential parameters must be evaluated; the storage capacity for the site must be acceptable for the project life of the operation, the trap configuration must be efficient to secure long term containment, the injectivity must be sufficient to secure a longstanding stable operation and finally a satisfactory and operational measuring strategy must be designed. The characterization procedure is demonstrated for a deep onshore aquifer in the northern part of Denmark, the Vedsted site. The site is an anticlinal structural closure in an Upper Triassic – Lower Jurassic sandstone formation at 1 800-1 900 m depth.


    Directory of Open Access Journals (Sweden)

    Carla Maria Abido Valentini


    Full Text Available Many research groups have being studying the contribution of tropical forests to the global carbon cycle, and theclimatic consequences of substituting the forests for pastures. Considering that soil CO2 efflux is the greater component of the carboncycle of the biosphere, this work found an equation for estimating the soil CO2 efflux of an area of the Transition Forest, using a modelof multiple regression for time series data of temperature and soil moisture. The study was carried out in the northwest of MatoGrosso, Brazil (11°24.75’S; 55°19.50’W, in a transition forest between cerrado and AmazonForest, 50 km far from Sinop county.Each month, throughout one year, it was measured soil CO2 efflux, temperature and soil moisture. The annual average of soil CO2 efflux was 7.5 ± 0.6 (mean ± SE ì mol m-2 s-1, the annual mean soil temperature was 25,06 ± 0.12 (mean ± SE ºC. The study indicatedthat the humidity had high influence on soil CO2 efflux; however the results were more significant using a multiple regression modelthat estimated the logarithm of soil CO2 efflux, considering time, soil moisture and the interaction between time duration and theinverse of soil temperature. .

  6. Estimation and diminution of CO2 emissions by clean development mechanism option at power sector in Oman

    Energy Technology Data Exchange (ETDEWEB)

    Singh Solanki, Parmal; Sarma Mallela, Venkateswara [Caledonian (University) College of Engineering, Muscat (Oman); Zhou, Chengke [Glasgow Caledonian University, Glasgow, Scotland (United Kingdom)


    Carbon dioxide (CO2) is one of the major pollutants among greenhouse gases emitted by fossil fuel based power plants and responsible for environmental tribulations. Therefore diminution of carbon dioxide level by Clean Development Mechanism (CDM) is now serious concern worldwide. This paper evaluates the emission factors of national electric grid in Oman and proposes a wind energy based CDM project to diminish the CO2 emissions. Estimations show that operating margin emission factors of national grid during five years lies in the range of 0.74 to 0.69 kg CO2/kWh. Further, proposed CDM project revealed the annual baseline emissions reduction of 45552 ton CO2 and able to earn the revenue of US$ 61.49 million by certify emission reductions in the first crediting period of project. Paper also critically analyse the opportunities for CDM project, its lucrative aspect, barrier and challenges.

  7. Simulation of a Potential CO2 Storage in the West Paris Basin: Site Characterization and Assessment of the Long-Term Hydrodynamical and Geochemical Impacts Induced by the CO2 Injection

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    Estublier Audrey


    Full Text Available This article presents the preliminary results of a study carried out as part of a demonstration project of CO2 storage in the Paris Basin. This project funded by ADEME (French Environment and Energy Management Agency and several industrial partners (TOTAL, ENGIE, EDF, Lafarge, Air Liquide, Vallourec aimed to study the possibility to set up an experimental infrastructure of CO2 transport and storage. Regarding the storage, the objectives were: (1 to characterize the selected site by optimizing the number of wells in a CO2 injection case of 200 Mt over 50 years in the Trias, (2 to simulate over time the CO2 migration and the induced pressure field, and (3 to analyze the geochemical behavior of the rock over the long term (1,000 years. The preliminary site characterization study revealed that only the southern area of Keuper succeeds to satisfy this injection criterion using only four injectors. However, a complementary study based on a refined fluid flow model with additional secondary faults concluded that this zone presents the highest potential of CO2 injection but without reaching the objective of 200 Mt with a reasonable number of wells. The simulation of the base scenario, carried out before the model refinement, showed that the overpressure above 0.1 MPa covers an area of 51,869 km2 in the Chaunoy formation, 1,000 years after the end of the injection, which corresponds to the whole West Paris Basin, whereas the CO2 plume extension remains small (524 km2. This overpressure causes brine flows at the domain boundaries and a local overpressure in the studied oil fields. Regarding the preliminary risk analysis of this project, the geochemical effects induced by the CO2 injection were studied by simulating the fluid-rock interactions with a coupled geochemical and fluid flow model in a domain limited to the storage complex. A one-way coupling of two models based on two domains fitting into each other was developed using dynamic boundary

  8. Pore Structure and Diagenetic Controls on Relative Permeability: Implications for Enhanced Oil Recovery and CO2 Storage (United States)

    Feldman, J.; Dewers, T. A.; Heath, J. E.; Cather, M.; Mozley, P.


    Multiphase flow in clay-bearing sandstones of the Morrow Sandstone governs the efficiency of CO2 storage and enhanced oil recovery at the Farnsworth Unit, Texas. This formation is the target for enhanced oil recovery and injection of one million metric ton of anthropogenically-sourced CO2. The sandstone hosts eight major flow units that exhibit distinct microstructural characteristics due to diagenesis, including: "clean" macro-porosity; quartz overgrowths constricting some pores; ghost grains; intergranular porosity filled by microporous authigenic clay; and feldspar dissolution. We examine the microstructural controls on macroscale (core scale) relative permeability and capillary pressure behavior through: X-ray computed tomography, Robomet.3d, and focused ion beam-scanning electron microscopy imaging of the pore structure of the major flow units of the Morrow Sandstone; relative permeability and capillary pressure in the laboratory using CO2, brine, and oil at reservoir pressure and effective stress conditions. The combined data sets inform links between patterns of diagenesis and multiphase flow. These data support multiphase reservoir simulation and performance assessment by the Southwest Regional Partnership on Carbon Sequestration (SWP). Funding for this project is provided by the U.S. Department of Energy's National Energy Technology Laboratory through the SWP under Award No. DE-FC26-05NT42591. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  9. The influence of water and supercritical CO2 on the frictional strength and velocity dependence of montmorillonite and muscovite and the potential for fault zone reactivation in CO2 storage reservoirs (United States)

    Samuelson, Jon


    Recent research indicates that CO2 is capable of inducing swelling in clay minerals in a similar fashion to water, though to a more modest extent. It is therefore of importance for feasibility studies of the geological storage of CO2 to understand if the addition of CO2 to clay rich fault zones has the potential to cause significant frictional weakening, similar to that associated with water. We conduct velocity-stepping direct shear experiments on pre-pressed plates (49 mm long x 35 mm wide x ~1 mm thick), of montmorillonite and muscovite. An effective normal stress of 35 MPa is used in all experiments, which is roughly equivalent to the effective overburden stress expected in many storage projects. Temperature was held constant at ~48 °C, consistent with previous experiments which indicated CO2 induced swelling in montmorillonite. Pore fluid conditions are the main variable in this suite of experiments, in which the frictional strength of each clay mineral is analyzed oven-dry (attached to vacuum), saturated with deionized (DI) water, and oven-dry saturated with supercritical CO2. Pore pressure is maintained at 15 MPa for the water and CO2 saturated experiments (?n=50 MPa, PH20-CO2=15 MPa). Shearing velocity is varied systematically from approximately 11 μm/s to 0.2, 1.1, 11, 1.1, and 0.2 μm/s in order to determine the rate and state friction parameters, a, b, and DC. Additionally, microstructural analysis of the post-shear clay gouges is conducted in an effort to understand the rheology behind changes observed in frictional properties. Preliminary results of experiments on montmorillonite show an overconsolidation peak at strains of approximately 0.3 for each of the oven-dry and water and CO2 saturated experiments. Peak friction (μP) for oven-dry montmorillonite is 0.53, decaying to a steady state friction (μSS) of 0.51. For DI-saturated montmorillonite μP=0.11 and μSS=0.10. CO2-saturated montmorillonite displays frictional strength between that of dry

  10. Calcium Carbonate Precipitation for CO2 Storage and Utilization: A Review of the Carbonate Crystallization and Polymorphism

    Directory of Open Access Journals (Sweden)

    Ribooga Chang


    Full Text Available The transformation of CO2 into a precipitated mineral carbonate through an ex situ mineral carbonation route is considered a promising option for carbon capture and storage (CCS since (i the captured CO2 can be stored permanently and (ii industrial wastes (i.e., coal fly ash, steel and stainless-steel slags, and cement and lime kiln dusts can be recycled and converted into value-added carbonate materials by controlling polymorphs and properties of the mineral carbonates. The final products produced by the ex situ mineral carbonation route can be divided into two categories—low-end high-volume and high-end low-volume mineral carbonates—in terms of their market needs as well as their properties (i.e., purity. Therefore, it is expected that this can partially offset the total cost of the CCS processes. Polymorphs and physicochemical properties of CaCO3 strongly rely on the synthesis variables such as temperature, pH of the solution, reaction time, ion concentration and ratio, stirring, and the concentration of additives. Various efforts to control and fabricate polymorphs of CaCO3 have been made to date. In this review, we present a summary of current knowledge and recent investigations entailing mechanistic studies on the formation of the precipitated CaCO3 and the influences of the synthesis factors on the polymorphs.

  11. TransCom 3: Seasonal CO2 Flux Estimates from Atmospheric Inversions (Level 2) (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides model outputs and seasonal mean CO2 fluxes from the Atmospheric Carbon Cycle Inversion Intercomparison (TransCom 3), Level 2...

  12. Monitoring of injected CO2 at two commercial geologic storage sites with significant pressure depletion and/or re-pressurization histories: A case study

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    Dayanand Saini


    The monitoring technologies that have been used/deployed/tested at both the normally pressured West Hastings and the subnormally pressured Bell Creek storage sites appear to adequately address any of the potential “out of zone migration” of injected CO2 at these sites. It would be interesting to see if any of the collected monitoring data at the West Hastings and the Bell Creek storage sites could also be used in future to better understand the viability of initially subnormally pressured and subsequently depleted and re-pressurized oil fields as secure geologic CO2 storage sites with relatively large storage CO2 capacities compared to the depleted and re-pressurized oil fields that were initially discovered as normally pressured.

  13. A missing element of the deep carbon cycle: CO2 degassing estimates from rift length analysis during Pangea fragmentation (United States)

    Brune, S.; Williams, S.; Müller, D.


    The deep carbon cycle connects CO2 within the atmosphere and oceans to the vast CO2 reservoir in Earth's mantle: subducted lithosphere carries CO2 into the mantle, while extensional plate boundaries and arc volcanoes release it back to Earth's surface. The length of plate boundaries thereby exerts first-order control on global CO2 fluxes on geological time scales. Here we provide a worldwide census of extensional plate boundary length from the Triassic to present day, in one million year time intervals, using a novel analysis technique (Brune et al. 2016, Nature, doi:10.1038/nature18319). The most extensive rift phase during the fragmentation of Pangea occurred in the Cretaceous with extension along the South Atlantic (9700 km) and North Atlantic rifts (9100 km), within East Gondwana (8500 km), and the failed African rift systems (4900 km). The combined extent of these and several smaller rifts amounts to more than 30.000 km of simultaneously active continental rifting. It is well-accepted that volcanoes at plate boundaries release large amounts of CO2 from the Earth's interior. Recent work, however, revealed the importance of deep-cutting faults and diffuse degassing on CO2 emissions in the East African rift (Lee et al. 2016, Nature Geoscience, doi: 10.1038/ngeo2622). Upscaling these measured CO2 fluxes to all concurrently active global rift zones, we compute first-order estimates of total rift-related CO2 degassing rates for the last 240 Myr. Our results show that rift-related CO2 release rates may have reached 600 Mt/yr in the Early Cretaceous, while Cenozoic rates rarely exceeded 200 Mt/yr. By comparison, present-day estimates of CO2 release at mid-ocean ridges range between 53 and 97 Mt/yr. We suggest that rift-related degassing during supercontinental breakup played a major role in maintaining high atmospheric CO2 concentrations through Mesozoic times, which exceeded Quaternary values by 400%.

  14. Hydro-mechanical simulations of well abandonment at the Ketzin pilot site for CO2 storage verify wellbore system integrity (United States)

    Unger, Victoria; Kempka, Thomas


    In geological underground utilisation, operating and abandoned wells have been identified as a main potential leakage pathways for reservoir fluids. In the scope of the well abandonment procedure currently carried out at the Ketzin pilot site for CO2 storage in Germany, a hydro-mechanical model was built to carry out a coupled analysis of the integrity in the entire wellbore system. The main aim of the present study was to assess the impacts of stress changes associated with CO2 injection as well as the cement backfill undertaken in the scope of well abandonment. A numerical model comprising cement sheaths, steel casings, tubing, multiple packers and wellbore annuli was implemented to enable a detailed representation of the entire wellbore system. The numerical model grid has a horizontal discretisation of 5 m x 5 m to focus on near wellbore effects, whereby element sizes increase with increasing distance from the wellbore. Vertical grid discretisation uses a tartan grid type over the entire model thickness of 1,500 m to ensure a sufficient discretisation of all wellbore system elements as well as of the reservoir unit. The total number of elements amounts to 210,672. Mechanical model parameters were taken from geological, drilling, logging and laboratory test data based on Ketzin pilot site-specific information as well as related literature (Kempka et al., 2014). The coupled calculations were performed using an elasto-plastic constitutive law, whereby an initial simulation run ensured a static mechanical equilibrium to represent the initial state before the start of CO2 injection. Thereto, gravitational load of the overburden rocks and pore pressure distribution following available well logs were integrated for initial model parameterisation including a normal faulting stress regime defined by a horizontal to vertical total stress ratio of 0.85. A correction accounting for the temperature and pressure dependent CO2 density was carried out in advance of each

  15. Tree height strongly affects estimates of water-use efficiency responses to climate and CO2 using isotopes. (United States)

    Brienen, R J W; Gloor, E; Clerici, S; Newton, R; Arppe, L; Boom, A; Bottrell, S; Callaghan, M; Heaton, T; Helama, S; Helle, G; Leng, M J; Mielikäinen, K; Oinonen, M; Timonen, M


    Various studies report substantial increases in intrinsic water-use efficiency (W i ), estimated using carbon isotopes in tree rings, suggesting trees are gaining increasingly more carbon per unit water lost due to increases in atmospheric CO2. Usually, reconstructions do not, however, correct for the effect of intrinsic developmental changes in W i as trees grow larger. Here we show, by comparing W i across varying tree sizes at one CO2 level, that ignoring such developmental effects can severely affect inferences of trees' W i . W i doubled or even tripled over a trees' lifespan in three broadleaf species due to changes in tree height and light availability alone, and there are also weak trends for Pine trees. Developmental trends in broadleaf species are as large as the trends previously assigned to CO2 and climate. Credible future tree ring isotope studies require explicit accounting for species-specific developmental effects before CO2 and climate effects are inferred.Intrinsic water-use efficiency (W i ) reconstructions using tree rings often disregard developmental changes in W i as trees age. Here, the authors compare W i across varying tree sizes at a fixed CO2 level and show that ignoring developmental changes impacts conclusions on trees' W i responses to CO2 or climate.

  16. The first 1-year-long estimate of the Paris region fossil fuel CO2 emissions based on atmospheric inversion (United States)

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


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

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

    Directory of Open Access Journals (Sweden)

    J. Staufer


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

  18. Impact and mitigation of borehole related effects in permanent crosshole resistivity imaging: An example from the Ketzin CO2 storage site (United States)

    Wagner, Florian M.; Bergmann, Peter; Rücker, Carsten; Wiese, Bernd; Labitzke, Tim; Schmidt-Hattenberger, Cornelia; Maurer, Hansruedi


    applied to a field data set from the Ketzin CO2 storage site, Germany, where crosshole electrical resistivity imaging is used for CO2 migration monitoring. The mitigation methods presented can improve estimates of the subsurface resistivity distribution, which, in our particular example, is an essential basis for the quantification of CO2 saturation from time-lapse geoelectrical measurements.

  19. Science in bullet points: How to compile scientific results to underpin guidelines for CO2 storage for the German transposition of the European CCS Directive (United States)

    Streibel, Martin


    In 2012 the German Parliament passed the transposition of the EC Directive 2009/31/EC the "Carbon Dioxide Storage Law" (KSpG). The law focuses on the demonstration of the CO2 storage technology and mainly regulates the storage part of the Carbon Capture and Storage (CCS) chain. As the law has a conceptual character, appendix 1 provides a description of criteria for the characterisation and assessment of a potential CO2 storage site starting with field data ending with requirements for dynamic modelling of the storage complex. Appendix 2 describes the expected monitoring system during all relevant phases of a life cycle of a CO2 storage site. The criteria given in the appendices are of general nature, which reflects on one hand that the CO2 storage technology is still being developed and on the other hand that site specific aspects needs to be considered. In 2004 the Federal Ministry of Education and Research of Germany launched the programme GEOTECHNOLOGIEN with one key aspect being the development of technologies for a sustainable storage of carbon dioxide in geological formations. Within this research field more than 30 projects in three phases have been funded until the end of 2014. In order to benefit from the gathered knowledge and use the experiences for the policy/law making process the umbrella project AUGE has been launched in October 2012 with a life time of three years. The aim of the project is to review and compile all results of projects funded during the three phases to underpin the appendices of the KSpG. In the first part of the paper the most important findings of the project with regard to the overall risk of a geological CO2 storage and the procedure of compiling the guidance document will be discussed. Milestones of this project were • the compilation of the results of national, European and international projects; • interviews with stakeholders; • a workshops to define state of the art for certain involved technologies and existing gaps

  20. Inversely estimating the vertical profile of the soil CO2 production rate in a deciduous broadleaf forest using a particle filtering method. (United States)

    Sakurai, Gen; Yonemura, Seiichiro; Kishimoto-Mo, Ayaka W; Murayama, Shohei; Ohtsuka, Toshiyuki; Yokozawa, Masayuki


    Carbon dioxide (CO2) efflux from the soil surface, which is a major source of CO2 from terrestrial ecosystems, represents the total CO2 production at all soil depths. Although many studies have estimated the vertical profile of the CO2 production rate, one of the difficulties in estimating the vertical profile is measuring diffusion coefficients of CO2 at all soil depths in a nondestructive manner. In this study, we estimated the temporal variation in the vertical profile of the CO2 production rate using a data assimilation method, the particle filtering method, in which the diffusion coefficients of CO2 were simultaneously estimated. The CO2 concentrations at several soil depths and CO2 efflux from the soil surface (only during the snow-free period) were measured at two points in a broadleaf forest in Japan, and the data were assimilated into a simple model including a diffusion equation. We found that there were large variations in the pattern of the vertical profile of the CO2 production rate between experiment sites: the peak CO2 production rate was at soil depths around 10 cm during the snow-free period at one site, but the peak was at the soil surface at the other site. Using this method to estimate the CO2 production rate during snow-cover periods allowed us to estimate CO2 efflux during that period as well. We estimated that the CO2 efflux during the snow-cover period (about half the year) accounted for around 13% of the annual CO2 efflux at this site. Although the method proposed in this study does not ensure the validity of the estimated diffusion coefficients and CO2 production rates, the method enables us to more closely approach the "actual" values by decreasing the variance of the posterior distribution of the values.

  1. Satellite-based estimates of reduced CO and CO2 emissions due to traffic restrictions during the 2008 Beijing Olympics (United States)

    Worden, Helen M.; Cheng, Yafang; Pfister, Gabriele; Carmichael, Gregory R.; Zhang, Qiang; Streets, David G.; Deeter, Merritt; Edwards, David P.; Gille, John C.; Worden, John R.


    During the 2008 Olympics, the Chinese government made a significant effort to improve air quality in Beijing, including restrictions on traffic. Here we estimate the reductions in carbon monoxide (CO) and carbon dioxide (CO2) emissions resulting from the control measures on Beijing transportation. Using MOPITT (Measurements Of Pollution In The Troposphere) multispectral satellite observations of near-surface CO along with WRF-Chem (Weather Research and Forecasting model with Chemistry) simulations for Beijing during August, 2007 and 2008, we estimate changes in CO due to meteorology and transportation sector emissions. Applying a reported CO/CO2 emission ratio for fossil fuels, we find the corresponding reduction in CO2, 60 ± 36 Gg[CO2]/day. As compared to emission scenarios being considered for the IPCC AR5 (Intergovernmental Panel on Climate Change, 5th Assessment Report), this result suggests that urban traffic controls on the Beijing Olympics scale could play a significant role in meeting target reductions for global CO2 emissions.

  2. Satellite based estimates of reduced CO and CO2 emissions due to traffic restrictions during the 2008 Beijing Olympics (United States)

    Worden, H. M.; Cheng, Y.; Pfister, G.; Carmichael, G. R.; Zhang, Q.; Streets, D. G.; Deeter, M. N.; Edwards, D. P.; Gille, J. C.; Worden, J.


    We present estimates of the reductions in CO and CO2 emissions resulting from the control measures on the Beijing transportation sector taken during the 2008 Beijing Olympics. This study used MOPITT (Measurements Of Pollution In The Troposphere) multispectral satellite measurements of near surface CO along with WRF Chem (Weather Research and Forecasting model with Chemistry) simulations for Beijing during August, 2007 and 2008 to estimate changes in CO due to meteorology and emissions. Using fractional changes in the emissions inventory transportation sector along with a reported CO/CO2 emission ratio for Beijing vehicles, we find the corresponding reduction in CO2 emissions. We then compare this reduction to target CO2 emissions in the RCP (representative concentration pathway) scenarios being considered for the IPCC AR5 (Intergovernmental Panel on Climate Change, 5th Assessment Report). Our result suggests that urban traffic reductions could play a significant role in meeting target cuts for global CO2 emissions, even for the most aggressive control scenario (RCP2.6).

  3. Relationship between Fiscal Subsidies and CO2 Emissions: Evidence from Cross-Country Empirical Estimates

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    Sacchidananda Mukherjee


    Full Text Available Countries disburse subsidies with various motivations, for example, to promote industrial development, facilitate innovation, support national champions, and ensure redistribution. The devolution of subsidies may however also encourage economic activities leading to climate change related concerns, reflected through higher greenhouse gases (GHGs emissions, if such activities are conducted beyond sustainable point. Through a cross-country empirical analysis involving 131 countries over 1990–2010, the present analysis observes that higher proportional devolution of budgetary subsidies leads to higher CO2 emissions. The countries with higher CO2 emissions are also characterized by higher per capita GDP, greater share of manufacturing sector in their GDP, and higher level of urbanization. In addition, the empirical findings underline the importance of the type of government subsidy devolution on CO2 emission pattern. The analysis underlines the importance of limiting provision of subsidies both in developed and developing countries.

  4. Biochemical Basis of CO2-Related Internal Browning Disorders in Pears (Pyrus communis L. cv. Rocha) during Long-Term Storage

    NARCIS (Netherlands)

    Deuchande, Teresa; Larrigaudière, Christian; Giné-bordonaba, Jordi; Pinto de Carvalho, Susana; Vasconcelos, Marta W.


    This study aimed at understanding the biochemical basis of internal browning disorders (IBDs) in ‘Rocha’ pear. For this purpose, the effects of storage under normal controlled atmosphere (CA) (3 kPa of O2 + 0.5 kPa of CO2) and IBD-inducing CA (1 kPa of O2 + 10 kPa of CO2) on the antioxidant and

  5. Energetic valorization of wood waste: estimation of the reduction in CO2 emissions. (United States)

    Vanneste, J; Van Gerven, T; Vander Putten, E; Van der Bruggen, B; Helsen, L


    This paper investigates the potential CO(2) emission reductions related to a partial switch from fossil fuel-based heat and electricity generation to renewable wood waste-based systems in Flanders. The results show that valorization in large-scale CHP (combined heat and power) systems and co-firing in coal plants have the largest CO(2) reduction per TJ wood waste. However, at current co-firing rates of 10%, the CO(2) reduction per GWh of electricity that can be achieved by co-firing in coal plants is five times lower than the CO(2) reduction per GWh of large-scale CHP. Moreover, analysis of the effect of government support for co-firing of wood waste in coal-fired power plants on the marginal costs of electricity generation plants reveals that the effect of the European Emission Trading Scheme (EU ETS) is effectively counterbalanced. This is due to the fact that biomass integrated gasification combined cycles (BIGCC) are not yet commercially available. An increase of the fraction of coal-based electricity in the total electricity generation from 8 to 10% at the expense of the fraction of gas-based electricity due to the government support for co-firing wood waste, would compensate entirely for the CO(2) reduction by substitution of coal by wood waste. This clearly illustrates the possibility of a 'rebound' effect on the CO(2) reduction due to government support for co-combustion of wood waste in an electricity generation system with large installed capacity of coal- and gas-based power plants, such as the Belgian one. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Regional Opportunities for Carbon Dioxide Capture and Storage in China: A Comprehensive CO2 Storage Cost Curve and Analysis of the Potential for Large Scale Carbon Dioxide Capture and Storage in the People’s Republic of China

    Energy Technology Data Exchange (ETDEWEB)

    Dahowski, Robert T.; Li, Xiaochun; Davidson, Casie L.; Wei, Ning; Dooley, James J.


    This study presents data and analysis on the potential for carbon dioxide capture and storage (CCS) technologies to deploy within China, including a survey of the CO2 source fleet and potential geologic storage capacity. The results presented here indicate that there is significant potential for CCS technologies to deploy in China at a level sufficient to deliver deep, sustained and cost-effective emissions reductions for China over the course of this century.

  7. Lake Metabolism: Comparison of Lake Metabolic Rates Estimated from a Diel CO2- and the Common Diel O2-Technique.

    Directory of Open Access Journals (Sweden)

    Frank Peeters

    Full Text Available Lake metabolism is a key factor for the understanding of turnover of energy and of organic and inorganic matter in lake ecosystems. Long-term time series on metabolic rates are commonly estimated from diel changes in dissolved oxygen. Here we present long-term data on metabolic rates based on diel changes in total dissolved inorganic carbon (DIC utilizing an open-water diel CO2-technique. Metabolic rates estimated with this technique and the traditional diel O2-technique agree well in alkaline Lake Illmensee (pH of ~8.5, although the diel changes in molar CO2 concentrations are much smaller than those of the molar O2 concentrations. The open-water diel CO2- and diel O2-techniques provide independent measures of lake metabolic rates that differ in their sensitivity to transport processes. Hence, the combination of both techniques can help to constrain uncertainties arising from assumptions on vertical fluxes due to gas exchange and turbulent diffusion. This is particularly important for estimates of lake respiration rates because these are much more sensitive to assumptions on gradients in vertical fluxes of O2 or DIC than estimates of lake gross primary production. Our data suggest that it can be advantageous to estimate respiration rates assuming negligible gradients in vertical fluxes rather than including gas exchange with the atmosphere but neglecting vertical mixing in the water column. During two months in summer the average lake net production was close to zero suggesting at most slightly autotrophic conditions. However, the lake emitted O2 and CO2 during the entire time period suggesting that O2 and CO2 emissions from lakes can be decoupled from the metabolism in the near surface layer.

  8. Lake Metabolism: Comparison of Lake Metabolic Rates Estimated from a Diel CO2- and the Common Diel O2-Technique. (United States)

    Peeters, Frank; Atamanchuk, Dariia; Tengberg, Anders; Encinas-Fernández, Jorge; Hofmann, Hilmar


    Lake metabolism is a key factor for the understanding of turnover of energy and of organic and inorganic matter in lake ecosystems. Long-term time series on metabolic rates are commonly estimated from diel changes in dissolved oxygen. Here we present long-term data on metabolic rates based on diel changes in total dissolved inorganic carbon (DIC) utilizing an open-water diel CO2-technique. Metabolic rates estimated with this technique and the traditional diel O2-technique agree well in alkaline Lake Illmensee (pH of ~8.5), although the diel changes in molar CO2 concentrations are much smaller than those of the molar O2 concentrations. The open-water diel CO2- and diel O2-techniques provide independent measures of lake metabolic rates that differ in their sensitivity to transport processes. Hence, the combination of both techniques can help to constrain uncertainties arising from assumptions on vertical fluxes due to gas exchange and turbulent diffusion. This is particularly important for estimates of lake respiration rates because these are much more sensitive to assumptions on gradients in vertical fluxes of O2 or DIC than estimates of lake gross primary production. Our data suggest that it can be advantageous to estimate respiration rates assuming negligible gradients in vertical fluxes rather than including gas exchange with the atmosphere but neglecting vertical mixing in the water column. During two months in summer the average lake net production was close to zero suggesting at most slightly autotrophic conditions. However, the lake emitted O2 and CO2 during the entire time period suggesting that O2 and CO2 emissions from lakes can be decoupled from the metabolism in the near surface layer.

  9. Multiannual changes of CO2 emissions in China: indirect estimates derived from satellite measurements of tropospheric NO2 columns

    Directory of Open Access Journals (Sweden)

    E. V. Berezin


    Full Text Available Multiannual satellite measurements of tropospheric NO2 columns are used for evaluation of CO2 emission changes in China in the period from 1996 to 2008. Indirect top-down annual estimates of CO2 emissions are derived from the satellite NO2 column measurements by means of a simple inverse modeling procedure involving simulations performed with the CHIMERE mesoscale chemistry–transport model and the CO2-to-NOx emission ratios from the Emission Database for Global Atmospheric Research (EDGAR global anthropogenic emission inventory and Regional Emission Inventory in Asia (REAS. Exponential trends in the normalized time series of annual emissions are evaluated separately for the periods from 1996 to 2001 and from 2001 to 2008. The results indicate that the both periods manifest strong positive trends in the CO2 emissions, and that the trend in the second period was significantly larger than the trend in the first period. Specifically, the trends in the first and second periods are best estimated to be in the range from 3.7 to 8.3 and from 11.0 to 13.2% per year, respectively, taking into account statistical uncertainties and differences between the CO2-to-NOx emission ratios from the EDGAR and REAS inventories. Comparison of our indirect top-down estimates of the CO2 emission changes with the corresponding bottom-up estimates provided by the EDGAR (version 4.2 and Global Carbon Project (GCP glomal emission inventories reveals that while acceleration of the CO2 emission growth in the considered period is a common feature of both kinds of estimates, nonlinearity in the CO2 emission changes may be strongly exaggerated in the global emission inventories. Specifically, the atmospheric NO2 observations do not confirm the existence of a sharp bend in the emission inventory data time series in the period from 2000 to 2002. A significant quantitative difference is revealed between the bottom-up and indirect top-down estimates of the CO2 emission trend in

  10. Highly Efficient Oxygen-Storage Material with Intrinsic Coke Resistance for Chemical Looping Combustion-Based CO2 Capture. (United States)

    Imtiaz, Qasim; Kurlov, Alexey; Rupp, Jennifer Lilia Marguerite; Müller, Christoph Rüdiger


    Chemical looping combustion (CLC) and chemical looping with oxygen uncoupling (CLOU) are emerging thermochemical CO2 capture cycles that allow the capture of CO2 with a small energy penalty. Here, the development of suitable oxygen carrier materials is a key aspect to transfer these promising concepts to practical installations. CuO is an attractive material for CLC and CLOU because of its high oxygen-storage capacity (20 wt %), fast reaction kinetics, and high equilibrium partial pressure of oxygen at typical operating temperatures (850-1000 °C). However, despite its promising characteristics, its low Tammann temperature requires the development of new strategies to phase-stabilize CuO-based oxygen carriers. In this work, we report a strategy based on stabilization by co-precipitated ceria (CeO2-x ), which allowed us to increase the oxygen capacity, coke resistance, and redox stability of CuO-based oxygen carriers substantially. The performance of the new oxygen carriers was evaluated in detail and compared to the current state-of-the-art materials, that is, Al2 O3 -stabilized CuO with similar CuO loadings. We also demonstrate that the higher intrinsic oxygen uptake, release, and mobility in CeO2-x -stabilized CuO leads to a three times higher carbon deposition resistance compared to that of Al2 O3 -stabilized CuO. Moreover, we report a high cyclic stability without phase intermixing for CeO2-x -supported CuO. This was accompanied by a lower reduction temperature compared to state-of-the-art Al2 O3 -supported CuO. As a result of its high resistance towards carbon deposition and fast oxygen uncoupling kinetics, CeO2-x -stabilized CuO is identified as a very promising material for CLC- and CLOU-based CO2 capture architectures. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Estimation of Total Yearly CO2 Emissions by Wildfires in Mexico during the Period 1999–2010

    Directory of Open Access Journals (Sweden)

    Flor Bautista Vicente


    Full Text Available The phenomenon of wildfires became a global environmental problem which demands estimations of their CO2 emissions. Wildfires have deteriorated the air quality increasingly. Using available information on documented wildfires and a data set of satellite detected hot spots, total yearly emissions of CO2 in Mexico were estimated for the period 1999–2010. A map of the main vegetation groups was used to calculate total areas for every vegetation type. The yearly number of hot spots per vegetation type was calculated. Estimates of emitted CO2 in a wildfire were then accomplished by considering parameters such as: forest fuel load, vegetation type, burning efficiency, and mean burned area. The number of wildfires and total affected areas showed an annual variability. The yearly mean of affected area by a single wildfire varied between 0.2 and 0.3 km2. The total affected area during the period 1999 to 2010 was 86800 km2 which corresponds to 4.3% of the Mexican territory. Total CO2 emissions were approximately 112 Tg. The most affected vegetation types were forest and rainforest.

  12. Effect of Sampling Depth on Air-Sea CO2 Flux Estimates in River-Stratified Arctic Coastal Waters (United States)

    Miller, L. A.; Papakyriakou, T. N.


    In summer-time Arctic coastal waters that are strongly influenced by river run-off, extreme stratification severely limits wind mixing, making it difficult to effectively sample the surface 'mixed layer', which can be as shallow as 1 m, from a ship. During two expeditions in southwestern Hudson Bay, off the Nelson, Hayes, and Churchill River estuaries, we confirmed that sampling depth has a strong impact on estimates of 'surface' pCO2 and calculated air-sea CO2 fluxes. We determined pCO2 in samples collected from 5 m, using a typical underway system on the ship's seawater supply; from the 'surface' rosette bottle, which was generally between 1 and 3 m; and using a niskin bottle deployed at 1 m and just below the surface from a small boat away from the ship. Our samples confirmed that the error in pCO2 derived from typical ship-board versus small-boat sampling at a single station could be nearly 90 μatm, leading to errors in the calculated air-sea CO2 flux of more than 0.1 mmol/(m2s). Attempting to extrapolate such fluxes over the 6,000,000 km2 area of the Arctic shelves would generate an error approaching a gigamol CO2/s. Averaging the station data over a cruise still resulted in an error of nearly 50% in the total flux estimate. Our results have implications not only for the design and execution of expedition-based sampling, but also for placement of in-situ sensors. Particularly in polar waters, sensors are usually deployed on moorings, well below the surface, to avoid damage and destruction from drifting ice. However, to obtain accurate information on air-sea fluxes in these areas, it is necessary to deploy sensors on ice-capable buoys that can position the sensors in true 'surface' waters.

  13. CO2 uptake of a mature Acacia mangium plantation estimated from sap flow measurements and stable carbon isotope discrimination (United States)

    Wang, H.; Zhao, P.; Zou, L. L.; McCarthy, H. R.; Zeng, X. P.; Ni, G. Y.; Rao, X. Q.


    A simple, nondestructive method for the estimation of canopy CO2 uptake is important for understanding the CO2 exchange between forest and atmosphere. Canopy CO2 uptake (FCO2) of a subtropical mature A. mangium plantation was estimated by combining sap flow measurements and stable carbon isotope discrimination (Δ) in Southern China from 2004 to 2007. The mechanistic relationship linking FCO2, Δ in leaf sap, and sap flow-based canopy stomatal conductance (Gs) was applied in our study. No significant seasonal variations were observed in Δ or in the ratio of the intercellular and ambient CO2 concentrations (Ci/Ca), although diurnal Ci/Ca varied between sunlit and shaded leaves. A sensitivity analysis showed that estimates of FCO2 were more sensitive to dynamics in Gs than in Ca and Δ. By using seasonally and canopy averaged Ci/Ca values, we obtained an acceptable estimate of FCO2 compared to other estimates. FCO2 exhibited similar diurnal variation to that of Gs. Large seasonal variation in FCO2 was attributed to the responsiveness of Gs to vapor pressure deficit, photosynthetically active radiation, and soil moisture deficit. Our estimate of FCO2 for a mature A. mangium plantation (2.13 ± 0.40 gC m-2 d-1) approached the lower range of values for subtropical mixed forests, probably due to lower mean canopy stomatal conductance, higher Ci/Ca, and greater tree height than other measured forests. Our estimate was also lower than values determined by satellite-based modeling or carbon allocation studies, suggesting the necessity of stand level flux data for verification. Qualitatively, the sap flux/stable isotope results compared well with gas exchange results. Differences in results between the two approaches likely reflected variability due to leaf position and age, which should be reduced for the combined sap flux and isotope technique, as it uses canopy average values of Gs and Ci/Ca.

  14. The potential of near-surface geophysical methods in a hierarchical monitoring approach for the detection of shallow CO2 seeps at geological storage sites (United States)

    Sauer, U.; Schuetze, C.; Dietrich, P.


    The MONACO project (Monitoring approach for geological CO2 storage sites using a hierarchic observation concept) aims to find reliable monitoring tools that work on different spatial and temporal scales at geological CO2 storage sites. This integrative hierarchical monitoring approach based on different levels of coverage and resolutions is proposed as a means of reliably detecting CO2 degassing areas at ground surface level and for identifying CO2 leakages from storage formations into the shallow subsurface, as well as CO2 releases into the atmosphere. As part of this integrative hierarchical monitoring concept, several methods and technologies from ground-based remote sensing (Open-path Fourier-transform infrared (OP-FTIR) spectroscopy), regional measurements (near-surface geophysics, chamber-based soil CO2 flux measurement) and local in-situ measurements (using shallow boreholes) will either be combined or used complementary to one another. The proposed combination is a suitable concept for investigating CO2 release sites. This also presents the possibility of adopting a modular monitoring concept whereby our monitoring approach can be expanded to incorporate other methods in various coverage scales at any temporal resolution. The link between information obtained from large-scale surveys and local in-situ monitoring can be realized by sufficient geophysical techniques for meso-scale monitoring, such as geoelectrical and self-potential (SP) surveys. These methods are useful for characterizing fluid flow and transport processes in permeable near-surface sedimentary layers and can yield important information concerning CO2-affected subsurface structures. Results of measurements carried out a natural analogue site in the Czech Republic indicate that the hierarchical monitoring approach represents a successful multidisciplinary modular concept that can be used to monitor both physical and chemical processes taking place during CO2 migration and seepage. The

  15. Impact of CO2 leakage from sub-seabed carbon dioxide capture and storage (CCS reservoirs on benthic virus-prokaryote interactions and functions

    Directory of Open Access Journals (Sweden)

    Eugenio eRastelli


    Full Text Available Atmospheric CO2 emissions are a global concern due to their predicted impact on biodiversity, ecosystems functioning and human life. Among the proposed mitigation strategies, CO2 capture and storage (CCS, primarily the injection of CO2 into marine deep geological formations has been suggested as a technically practical option for reducing emissions. However, concerns have been raised that possible leakage from such storage sites, and the associated elevated levels of pCO2 could locally impact the biodiversity and biogeochemical processes in the sediments above these reservoirs. Whilst a number of impact assessment studies have been conducted, no information is available on the specific responses of viruses and virus-host interactions. In the present study, we tested the impact of a simulated CO2 leakage on the benthic microbial assemblages, with specific focus on microbial activity and virus-induced prokaryotic mortality. We found that exposure to levels of CO2 in the overlying seawater from 1,000 ppm to 20,000 ppm for a period up to 140 days, resulted in a marked decrease in heterotrophic carbon production and organic matter degradation rates in the sediments, associated with lower rates of virus-induced prokaryotic mortality, and a progressive accumulation of sedimentary organic matter with increasing CO2 concentrations. These results suggest that the increase in seawater pCO2 levels that may result from CO2 leakage, can severely reduce the rates of microbial-mediated recycling of the sedimentary organic matter and viral infections, with major consequences on C cycling and nutrient regeneration, and hence on the functioning of benthic ecosystems.

  16. Process-based estimates of terrestrial ecosystem isoprene emissions: incorporating the effects of a direct CO2-isoprene interaction

    Directory of Open Access Journals (Sweden)

    A. Arneth


    Full Text Available In recent years evidence has emerged that the amount of isoprene emitted from a leaf is affected by the CO2 growth environment. Many – though not all – laboratory experiments indicate that emissions increase significantly at below-ambient CO2 concentrations and decrease when concentrations are raised to above-ambient. A small number of process-based leaf isoprene emission models can reproduce this CO2 stimulation and inhibition. These models are briefly reviewed, and their performance in standard conditions compared with each other and to an empirical algorithm. One of the models was judged particularly useful for incorporation into a dynamic vegetation model framework, LPJ-GUESS, yielding a tool that allows the interactive effects of climate and increasing CO2 concentration on vegetation distribution, productivity, and leaf and ecosystem isoprene emissions to be explored. The coupled vegetation dynamics-isoprene model is described and used here in a mode particularly suited for the ecosystem scale, but it can be employed at the global level as well. Annual and/or daily isoprene emissions simulated by the model were evaluated against flux measurements (or model estimates that had previously been evaluated with flux data from a wide range of environments, and agreement between modelled and simulated values was generally good. By using a dynamic vegetation model, effects of canopy composition, disturbance history, or trends in CO2 concentration can be assessed. We show here for five model test sites that the suggested CO2-inhibition of leaf-isoprene metabolism can be large enough to offset increases in emissions due to CO2-stimulation of vegetation productivity and leaf area growth. When effects of climate change are considered atop the effects of atmospheric composition the interactions between the relevant processes will become even more complex. The CO2-isoprene inhibition may have the potential to significantly dampen the expected steep

  17. Carbon accounting and cost estimation in forestry projects using CO2Fix V.3


    Groen, T.A.; G. J. Nabuurs; Schelhaas, M.J.


    Carbon and financial accounting of projects in the Land Use, Land-Use Change and Forestry sector is a topic of hot debate. Large uncertainty remains concerning the carbon dynamics, the way they should be accounted and the cost efficiency of the projects. Part of the uncertainty can be alleviated by standardisation and transparency of reporting methods. For this reason we further developed CO2FIX, a forest ecosystem carbon model, with modules for carbon and financial accounting. The model is a...

  18. A bottom up approach to on-road CO2 emissions estimates: improved spatial accuracy and applications for regional planning. (United States)

    Gately, Conor K; Hutyra, Lucy R; Wing, Ian Sue; Brondfield, Max N


    On-road transportation is responsible for 28% of all U.S. fossil-fuel CO2 emissions. Mapping vehicle emissions at regional scales is challenging due to data limitations. Existing emission inventories use spatial proxies such as population and road density to downscale national or state-level data. Such procedures introduce errors where the proxy variables and actual emissions are weakly correlated, and limit analysis of the relationship between emissions and demographic trends at local scales. We develop an on-road emission inventory product for Massachusetts-based on roadway-level traffic data obtained from the Highway Performance Monitoring System (HPMS). We provide annual estimates of on-road CO2 emissions at a 1 × 1 km grid scale for the years 1980 through 2008. We compared our results with on-road emissions estimates from the Emissions Database for Global Atmospheric Research (EDGAR), with the Vulcan Product, and with estimates derived from state fuel consumption statistics reported by the Federal Highway Administration (FHWA). Our model differs from FHWA estimates by less than 8.5% on average, and is within 5% of Vulcan estimates. We found that EDGAR estimates systematically exceed FHWA by an average of 22.8%. Panel regression analysis of per-mile CO2 emissions on population density at the town scale shows a statistically significant correlation that varies systematically in sign and magnitude as population density increases. Population density has a positive correlation with per-mile CO2 emissions for densities below 2000 persons km(-2), above which increasing density correlates negatively with per-mile emissions.

  19. Approximate solutions for diffusive fracture-matrix transfer: Application to storage of dissolved CO2 in fractured rocks (United States)

    Zhou, Quanlin; Oldenburg, Curtis M.; Spangler, Lee H.; Birkholzer, Jens T.


    Analytical solutions with infinite exponential series are available to calculate the rate of diffusive transfer between low-permeability blocks and high-permeability zones in the subsurface. Truncation of these series is often employed by neglecting the early-time regime. In this paper, we present unified-form approximate solutions in which the early-time and the late-time solutions are continuous at a switchover time. The early-time solutions are based on three-term polynomial functions in terms of square root of dimensionless time, with the first coefficient dependent only on the dimensionless area-to-volume ratio. The last two coefficients are either determined analytically for isotropic blocks (e.g., spheres and slabs) or obtained by fitting the exact solutions, and they solely depend on the aspect ratios for rectangular columns and parallelepipeds. For the late-time solutions, only the leading exponential term is needed for isotropic blocks, while a few additional exponential terms are needed for highly anisotropic rectangular blocks. The optimal switchover time is between 0.157 and 0.229, with highest relative approximation error less than 0.2%. The solutions are used to demonstrate the storage of dissolved CO2 in fractured reservoirs with low-permeability matrix blocks of single and multiple shapes and sizes. These approximate solutions are building blocks for development of analytical and numerical tools for hydraulic, solute, and thermal diffusion processes in low-permeability matrix blocks.

  20. An approach for monitoring resistivity variations using surface magnetotelluric data and its application to CO2 storage site (United States)

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


    In this work we present an approach to perform electromagnetic (EM) monitoring using surface magnetotelluric (MT) data. The proposed methodology, called layer stripping, is based on the analytical solution of the one-dimensional MT problem and the fact that resolution to resistivity changes produced at a given depth increase when increasing the depth at which data are acquired. Thus, giving a well-known geoelectrical baseline model of a reservoir site, the layer stripping approach aims to remove the effect of the upper, unchanging, structures in order to obtain the time-varying MT responses at the target depth. In this paper the proposed method is tested and validated using the 3D geoelectrical baseline model of the Hontomín site (Spain) for CO2 geological storage in a deep saline aquifer. The 3D resistivity model of Hontomín defines the subsurface in the pre-injection state, showing the dome-like structure of the saline aquifer and imaging the principal set of faults. For monitoring purposes, the model allows obtaining the MT responses at the main reservoir depth using the layer stripping approach to remove the upper structures not affected by the injection of the gas. The results obtained in this work suggest that the layer stripping method improves the resolution of surface MT responses being able to detect smaller resistivity changes.

  1. Risk Assessment-Led Characterisation of the SiteChar UK North Sea Site for the Geological Storage of CO2

    Directory of Open Access Journals (Sweden)

    Akhurst Maxine


    Full Text Available Risk assessment-led characterisation of a site for the geological storage of CO2 in the UK northern North Sea was performed for the EU SiteChar research project as one of a portfolio of sites. Implementation and testing of the SiteChar project site characterisation workflow has produced a ‘dry-run’ storage permit application that is compliant with regulatory requirements. A site suitable for commercial-scale storage was characterised, compatible with current and future industrial carbon dioxide (CO2 sources in the northern UK. Pre-characterisation of the site, based on existing information acquired during hydrocarbon exploration and production, has been achieved from publicly available data. The project concept is to store captured CO2 at a rate of 5 Mt per year for 20 years in the Blake Oil Field and surrounding Captain Sandstone saline aquifer. This commercial-scale storage of 100 Mt CO2 can be achieved through a storage scenario combining injection of CO2 into the oil field and concurrent water production down-dip of the field. There would be no encroachment of supercritical phase CO2 for more than two kilometres beyond the field boundary and no adverse influence on operating hydrocarbon fields provided there is pressure management. Components of a storage permit application for the site are presented, developed as far as possible within a research project. Characterisation and technical investigations were guided by an initial assessment of perceived risks to the prospective site and a need to provide the information required for the storage permit application. The emphasis throughout was to reduce risks and uncertainty on the subsurface containment of stored CO2, particularly with respect to site technical performance, monitoring and regulatory issues, and effects on other resources. The results of selected risk assessment-led site characterisation investigations and the subsequent risk reassessments are described together with their

  2. Integrated modeling of CO2 storage and leakage scenarios including transitions between super- and sub-critical conditions, and phase change between liquid and gaseous CO2

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, K.


    Storage of CO{sub 2} in saline aquifers is intended to be at supercritical pressure and temperature conditions, but CO{sub 2} leaking from a geologic storage reservoir and migrating toward the land surface (through faults, fractures, or improperly abandoned wells) would reach subcritical conditions at depths shallower than 500-750 m. At these and shallower depths, subcritical CO{sub 2} can form two-phase mixtures of liquid and gaseous CO{sub 2}, with significant latent heat effects during boiling and condensation. Additional strongly non-isothermal effects can arise from decompression of gas-like subcritical CO{sub 2}, the so-called Joule-Thomson effect. Integrated modeling of CO{sub 2} storage and leakage requires the ability to model non-isothermal flows of brine and CO{sub 2} at conditions that range from supercritical to subcritical, including three-phase flow of aqueous phase, and both liquid and gaseous CO{sub 2}. In this paper, we describe and demonstrate comprehensive simulation capabilities that can cope with all possible phase conditions in brine-CO{sub 2} systems. Our model formulation includes: (1) an accurate description of thermophysical properties of aqueous and CO{sub 2}-rich phases as functions of temperature, pressure, salinity and CO{sub 2} content, including the mutual dissolution of CO{sub 2} and H{sub 2}O; (2) transitions between super- and subcritical conditions, including phase change between liquid and gaseous CO{sub 2}; (3) one-, two-, and three-phase flow of brine-CO{sub 2} mixtures, including heat flow; (4) non-isothermal effects associated with phase change, mutual dissolution of CO{sub 2} and water, and (de-) compression effects; and (5) the effects of dissolved NaCl, and the possibility of precipitating solid halite, with associated porosity and permeability change. Applications to specific leakage scenarios demonstrate that the peculiar thermophysical properties of CO{sub 2} provide a potential for positive as well as negative

  3. Research Project on CO2 Geological Storage and Groundwater Resources: Water Quality Effects Caused by CO2 Intrusion into Shallow Groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Birkholzer, Jens; Apps, John; Zheng, Liange; Zhang, Yingqi; Xu, Tianfu; Tsang, Chin-Fu


    One promising approach to reduce greenhouse gas emissions is injecting CO{sub 2} into suitable geologic formations, typically depleted oil/gas reservoirs or saline formations at depth larger than 800 m. Proper site selection and management of CO{sub 2} storage projects will ensure that the risks to human health and the environment are low. However, a risk remains that CO{sub 2} could migrate from a deep storage formation, e.g. via local high-permeability pathways such as permeable faults or degraded wells, and arrive in shallow groundwater resources. The ingress of CO{sub 2} is by itself not typically a concern to the water quality of an underground source of drinking water (USDW), but it will change the geochemical conditions in the aquifer and will cause secondary effects mainly induced by changes in pH, in particular the mobilization of hazardous inorganic constituents present in the aquifer minerals. Identification and assessment of these potential effects is necessary to analyze risks associated with geologic sequestration of CO{sub 2}. This report describes a systematic evaluation of the possible water quality changes in response to CO{sub 2} intrusion into aquifers currently used as sources of potable water in the United States. Our goal was to develop a general understanding of the potential vulnerability of United States potable groundwater resources in the event of CO{sub 2} leakage. This goal was achieved in two main tasks, the first to develop a comprehensive geochemical model representing typical conditions in many freshwater aquifers (Section 3), the second to conduct a systematic reactive-transport modeling study to quantify the effect of CO{sub 2} intrusion into shallow aquifers (Section 4). Via reactive-transport modeling, the amount of hazardous constituents potentially mobilized by the ingress of CO{sub 2} was determined, the fate and migration of these constituents in the groundwater was predicted, and the likelihood that drinking water

  4. Short-term treatments with high CO2and low O2concentrations on quality of fresh goji berries (Lycium barbarum L.) during cold storage. (United States)

    Kafkaletou, Mina; Christopoulos, Miltiadis V; Tsantili, Eleni


    Goji berries (Lycium barbarum L.) are functional fruits but are usually marketed as a dried product. The aim of this study was to investigate the storability of fresh goji berries treated with high CO 2 and low O 2 concentrations before air storage at 1 °C for 21 days. Berries harvested without stems were exposed to air (controls) or subjected for 2 days at 1 °C to the following controlled atmosphere (CA) treatments: 21% O 2 + 0% CO 2 (21+0), 5% O 2 + 15% CO 2 (5+15), 10% O 2 + 10% CO 2 (10+10) and 20% O 2 + 20% CO 2 (20+20). During 14 days of storage, all treatments decreased weight loss, while treatments 5+15 and 20+20 prevented fungal decay. No fermentation was observed. The treatments did not affect color changes, decreases in soluble sugars and increases in total soluble solids, titratable acidity, ascorbic acid, total carotenoids, total phenolics and ferric-reducing antioxidant power (FRAP) during storage, apart from the marginally reduced FRAP by treatment 20+20 on day 7. Treatments 5+15, 10+10 and 20+20 resulted in residual decreases in respiration rates and pH values early during storage. After 14 days of storage, panelists rated the CA-treated samples as sweet, with good acceptance. Treatments 5+15 and 20+20 showed the best results after 14 days of storage. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  5. Reversible hydrogen storage using CO2 and a proton-switchable iridium catalyst in aqueous media under mild temperatures and pressures. (United States)

    Hull, Jonathan F; Himeda, Yuichiro; Wang, Wan-Hui; Hashiguchi, Brian; Periana, Roy; Szalda, David J; Muckerman, James T; Fujita, Etsuko


    Green plants convert CO(2) to sugar for energy storage via photosynthesis. We report a novel catalyst that uses CO(2) and hydrogen to store energy in formic acid. Using a homogeneous iridium catalyst with a proton-responsive ligand, we show the first reversible and recyclable hydrogen storage system that operates under mild conditions using CO(2), formate and formic acid. This system is energy-efficient and green because it operates near ambient conditions, uses water as a solvent, produces high-pressure CO-free hydrogen, and uses pH to control hydrogen production or consumption. The extraordinary and switchable catalytic activity is attributed to the multifunctional ligand, which acts as a proton-relay and strong π-donor, and is rationalized by theoretical and experimental studies.

  6. Simulation of CO2 Sequestration at Rock Spring Uplift, Wyoming: Heterogeneity and Uncertainties in Storage Capacity, Injectivity and Leakage

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Hailin [Los Alamos National Laboratory; Dai, Zhenxue [Los Alamos National Laboratory; Jiao, Zunsheng [Wyoming State Geological Survey; Stauffer, Philip H. [Los Alamos National Laboratory; Surdam, Ronald C. [Wyoming State Geological Survey


    Many geological, geochemical, geomechanical and hydrogeological factors control CO{sub 2} storage in subsurface. Among them heterogeneity in saline aquifer can seriously influence design of injection wells, CO{sub 2} injection rate, CO{sub 2} plume migration, storage capacity, and potential leakage and risk assessment. This study applies indicator geostatistics, transition probability and Markov chain model at the Rock Springs Uplift, Wyoming generating facies-based heterogeneous fields for porosity and permeability in target saline aquifer (Pennsylvanian Weber sandstone) and surrounding rocks (Phosphoria, Madison and cap-rock Chugwater). A multiphase flow simulator FEHM is then used to model injection of CO{sub 2} into the target saline aquifer involving field-scale heterogeneity. The results reveal that (1) CO{sub 2} injection rates in different injection wells significantly change with local permeability distributions; (2) brine production rates in different pumping wells are also significantly impacted by the spatial heterogeneity in permeability; (3) liquid pressure evolution during and after CO{sub 2} injection in saline aquifer varies greatly for different realizations of random permeability fields, and this has potential important effects on hydraulic fracturing of the reservoir rock, reactivation of pre-existing faults and the integrity of the cap-rock; (4) CO{sub 2} storage capacity estimate for Rock Springs Uplift is 6614 {+-} 256 Mt at 95% confidence interval, which is about 36% of previous estimate based on homogeneous and isotropic storage formation; (5) density profiles show that the density of injected CO{sub 2} below 3 km is close to that of the ambient brine with given geothermal gradient and brine concentration, which indicates CO{sub 2} plume can sink to the deep before reaching thermal equilibrium with brine. Finally, we present uncertainty analysis of CO{sub 2} leakage into overlying formations due to heterogeneity in both the target saline

  7. 1:1 scale wellbore experiment and associated modeling for a better understanding of well integrity in the context of CO2 geological storage

    NARCIS (Netherlands)

    Manceau, J.C.; Trémosa, J.; Audigane, P.; Claret, F.; Wasch, L.J.; Gherardi, F.; Ukelis, O.; Dimier, A.; Nussbaum, C.; Lettry, Y.; Fierz, T.


    In this study, we present a new experiment for following the evolution of the well integrity over time due to different changes in well conditions (pressure, temperature and fluids in contact with the well) in the context of CO2 geological storage. A small section of a wellbore is reproduced in the

  8. Two-Stage, Integrated, Geothermal-CO2 Storage Reservoirs: An Approach for Sustainable Energy Production, CO2-Sequestration Security, and Reduced Environmental Risk

    Energy Technology Data Exchange (ETDEWEB)

    Buscheck, T A; Chen, M; Sun, Y; Hao, Y; Elliot, T R


    We introduce a hybrid two-stage energy-recovery approach to sequester CO{sub 2} and produce geothermal energy at low environmental risk and low cost by integrating geothermal production with CO{sub 2} capture and sequestration (CCS) in saline, sedimentary formations. Our approach combines the benefits of the approach proposed by Buscheck et al. (2011b), which uses brine as the working fluid, with those of the approach first suggested by Brown (2000) and analyzed by Pruess (2006), using CO{sub 2} as the working fluid, and then extended to saline-formation CCS by Randolph and Saar (2011a). During stage one of our hybrid approach, formation brine, which is extracted to provide pressure relief for CO{sub 2} injection, is the working fluid for energy recovery. Produced brine is applied to a consumptive beneficial use: feedstock for fresh water production through desalination, saline cooling water, or make-up water to be injected into a neighboring reservoir operation, such as in Enhanced Geothermal Systems (EGS), where there is often a shortage of a working fluid. For stage one, it is important to find economically feasible disposition options to reduce the volume of brine requiring reinjection in the integrated geothermal-CCS reservoir (Buscheck et al. 2012a). During stage two, which begins as CO{sub 2} reaches the production wells; coproduced brine and CO{sub 2} are the working fluids. We present preliminary reservoir engineering analyses of this approach, using a simple conceptual model of a homogeneous, permeable CO{sub 2} storage formation/geothermal reservoir, bounded by relatively impermeable sealing units. We assess both the CO{sub 2} sequestration capacity and geothermal energy production potential as a function of well spacing between CO{sub 2} injectors and brine/CO{sub 2} producers for various well patterns and for a range of subsurface conditions.

  9. Enhanced geothermal systems (EGS) with CO2 as heat transmission fluid--A scheme for combining recovery of renewable energy with geologic storage of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, K.; Spycher, N.


    It has been suggested that enhanced geothermal systems (EGS) may be operated with supercritical CO{sub 2} instead of water as heat transmission fluid (D.W. Brown, 2000). Such a scheme could combine recovery of geothermal energy with simultaneous geologic storage of CO{sub 2}, a greenhouse gas. At geothermal temperature and pressure conditions of interest, the flow and heat transfer behavior of CO{sub 2} would be considerably different from water, and chemical interactions between CO{sub 2} and reservoir rocks would also be quite different from aqueous fluids. This paper summarizes our research to date into fluid flow and heat transfer aspects of operating EGS with CO{sub 2}. (Chemical aspects of EGS with CO{sub 2} are discussed in a companion paper; Xu and Pruess, 2010.) Our modeling studies indicate that CO{sub 2} would achieve heat extraction at larger rates than aqueous fluids. The development of an EGS-CO{sub 2} reservoir would require replacement of the pore water by CO{sub 2} through persistent injection. We find that in a fractured reservoir, CO{sub 2} breakthrough at production wells would occur rapidly, within a few weeks of starting CO{sub 2} injection. Subsequently a two-phase water-CO{sub 2} mixture would be produced for a few years,followed by production of a single phase of supercritical CO{sub 2}. Even after single-phase production conditions are reached,significant dissolved water concentrations will persist in the CO{sub 2} stream for many years. The presence of dissolved water in the production stream has negligible impact on mass flow and heat transfer rates.

  10. Estimating surface pCO2 in the northern Gulf of Mexico: Which remote sensing model to use? (United States)

    Chen, Shuangling; Hu, Chuanmin; Cai, Wei-Jun; Yang, Bo


    Various approaches and models have been proposed to remotely estimate surface pCO2 in the ocean, with variable performance as they were designed for different environments. Among these, a recently developed mechanistic semi-analytical approach (MeSAA) has shown its advantage for its explicit inclusion of physical and biological forcing in the model, yet its general applicability is unknown. Here, with extensive in situ measurements of surface pCO2, the MeSAA, originally developed for the summertime East China Sea, was tested in the northern Gulf of Mexico (GOM) where river plumes dominate water's biogeochemical properties during summer. Specifically, the MeSAA-predicted surface pCO2 was estimated by combining the dominating effects of thermodynamics, river-ocean mixing and biological activities on surface pCO2. Firstly, effects of thermodynamics and river-ocean mixing (pCO2@Hmixing) were estimated with a two-endmember mixing model, assuming conservative mixing. Secondly, pCO2 variations caused by biological activities (ΔpCO2@bio) was determined through an empirical relationship between sea surface temperature (SST)-normalized pCO2 and MODIS (Moderate Resolution Imaging Spectroradiometer) 8-day composite chlorophyll concentration (CHL). The MeSAA-modeled pCO2 (sum of pCO2@Hmixing and ΔpCO2@bio) was compared with the field-measured pCO2. The Root Mean Square Error (RMSE) was 22.94 μatm (5.91%), with coefficient of determination (R2) of 0.25, mean bias (MB) of - 0.23 μatm and mean ratio (MR) of 1.001, for pCO2 ranging between 316 and 452 μatm. To improve the model performance, a locally tuned MeSAA was developed through the use of a locally tuned ΔpCO2@bio term. A multi-variate empirical regression model was also developed using the same dataset. Both the locally tuned MeSAA and the regression models showed improved performance comparing to the original MeSAA, with R2 of 0.78 and 0.84, RMSE of 12.36 μatm (3.14%) and 10.66 μatm (2.68%), MB of 0.00 μatm and - 0

  11. Partitioning of CO(2) incorporation among planktonic microbial guilds and estimation of in situ specific growth rates. (United States)

    García-Cantizano, Josefina; Casamayor, Emilio O; Gasol, Josep M; Guerrero, Ricardo; Pedrós-Alió, Carlos


    Partitioning of CO(2) incorporation into oxygenic phototrophic, anoxygenic phototrophic, and chemolithoautotrophic guilds was determined in a freshwater lake (Lake Cisó, Banyoles, Spain). CO(2) incorporation into the different types of microorganisms was studied at different depths, during diel cycles, and throughout the year. During winter holomixis, the whole lake became anoxic and both the anoxygenic and chemolithoautotrophic guilds were more active at the surface of the lake, whereas the activity of the oxygenic guild was negligible. During stratification, the latter guild was more active in the upper metalimnion, whereas the anoxygenic guild was more active in the lower metalimnion. Specific growth rates and doubling times were estimated for the most conspicuous phototrophic microorganisms. Doubling times for Cryptomonas phaseolus ranged between 0.5 and 192 days, whereas purple sulfur bacteria (Chromatiaceae-like) ranged between 1.5 and 238 days. These growth rates were similar to those calculated with a different approach in previous papers and indicate slow-growing populations with very large biomass. Overall, the annual total CO(2) incorporation in Lake Cisó was 220 g C m(-2). Most of the CO(2) incorporation, however, was due to the chemolithoautotrophic guild (61% during holomixis and 56% during stratification), followed by the anoxygenic phototrophic guild (35 and 19%, respectively) and the oxygenic phototrophs (4 and 25%, respectively), making dark carbon fixation the key process in the autotrophic metabolism of the lake.

  12. Preliminary Modelling of the Effect of Impurity in CO2 Streams on the Storage Capacity and the Plume Migration in Pohang Basin, Korea (United States)

    Park, Yongchan; Choi, Byoungyoung; Shinn, Youngjae


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

  13. Sensitivity of global and regional terrestrial carbon storage to the direct CO2 effect and climate change based on the CMIP5 model intercomparison. (United States)

    Peng, Jing; Dan, Li; Huang, Mei


    Global and regional land carbon storage has been significantly affected by increasing atmospheric CO2 concentration and climate change. Based on fully coupled climate-carbon-cycle simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5), we investigate sensitivities of land carbon storage to rising atmospheric CO2 concentration and climate change over the world and 21 regions during the 130 years. Overall, the simulations suggest that consistently spatial positive effects of the increasing CO2 concentrations on land carbon storage are expressed with a multi-model averaged value of 1.04 PgC per ppm. The stronger positive values are mainly located in the broad areas of temperate and tropical forest, especially in Amazon basin and western Africa. However, large heterogeneity distributed for sensitivities of land carbon storage to climate change. Climate change causes decrease in land carbon storage in most tropics and the Southern Hemisphere. In these regions, decrease in soil moisture (MRSO) and enhanced drought somewhat contribute to such a decrease accompanied with rising temperature. Conversely, an increase in land carbon storage has been observed in high latitude and altitude regions (e.g., northern Asia and Tibet). The model simulations also suggest that global negative impacts of climate change on land carbon storage are predominantly attributed to decrease in land carbon storage in tropics. Although current warming can lead to an increase in land storage of high latitudes of Northern Hemisphere due to elevated vegetation growth, a risk of exacerbated future climate change may be induced due to release of carbon from tropics.

  14. SiteChar. Characterisation of European CO2 storage. Deliverable D8.1. Qualitative and quantitative social site characterisations

    Energy Technology Data Exchange (ETDEWEB)

    Brunsting, S.; Pol, M.; Paukovic, M. [ECN Policy Studies, Energy research Centre of the Netherlands ECN, Amsterdam (Netherlands); Kaiser, M.; Zimmer, R. [Unabhaengiges Institut fuer Umweltfragen UfU, Berlin (Germany); Shackley, S.; Mabon, L. [Scottish Carbon Capture and Storage SCCS, Edinburg, Scotland (United Kingdom); Hepplewhite, F.; Loveridge, R. [Energy Markets Unit, Scottish Government, Edinburg, Scotland (United Kingdom); Mazurowski, M.; Polak-Osiniak, D. [Polish Oil and Gas Company PGNiG, Warszawa (Poland); Rybicki, C. [AGH University of Science and Technology, Krakow (Poland)


    At local level, public support has proven crucial to the implementation of CO2 capture and storage (CCS) demonstration projects. Whereas no method exists to guarantee public acceptability of any project, a constructive stakeholder engagement process does increase the likelihood thereof. Social site characterisation can be used as an instrument to explore, plan and evaluate a process of active and constructive local stakeholder engagement in a prospective CCS project as a parallel activity to technical site characterisation. It roughly consists of a formative research phase to get acquainted with the area followed by a series of public information and engagement activities. This deliverable presents results from the first phase for the social site characterisations of a prospective CCS site in Poland (onshore) and the UK (offshore), using qualitative as well as quantitative research methods, as a first step to planning of local public engagement activities and evaluation of these activities that will be undertaken by this consortium at both sites in the near future. Although the term social site characterisation actually refers to the entire process of formative research and subsequent public outreach, and hence to the complete package of awareness work undertaken as part of SiteChar, in the present deliverable the term only refers to the formative research activities as undertaken up to now and as described in this deliverable. The qualitative part of the social site characterisation consisted of (1) a description of relevant social site characteristics such as local history; (2) interviews with relevant local stakeholders; (3) a media analysis of local newspapers. The quantitative part of the social site characterisation consisted of surveys using representative samples to characterise the local population in terms of awareness, knowledge and perceptions of CCS, felt involvement in decision making, extent of local activism, level of trust in representatives and

  15. Estimating Landfill Methane Oxidation Using the Information of CO2/CH4 Fluxes Measured By the Eddy Covariance Method (United States)

    Xu, L.; McDermitt, D. K.; Li, J.; Green, R. B.


    Methane plays a critical role in the radiation balance and chemistry of the atmosphere. Globally, landfill methane emission contributes about 10-19% of the anthropogenic methane burden into the atmosphere. In the United States, 18% of annual anthropogenic methane emissions come from landfills, which represent the third largest source of anthropogenic methane emissions, behind enteric fermentation and natural gas and oil production. One uncertainty in estimating landfill methane emissions is the fraction of methane oxidized when methane produced under anaerobic conditions passes through the cover soil. We developed a simple stoichiometric model to estimate the landfill methane oxidation fraction when the anaerobic CO2/CH4 production ratio is known. The model predicts a linear relationship between CO2 emission rates and CH4 emission rates, where the slope depends on anaerobic CO2/CH4 production ratio and the fraction of methane oxidized, and the intercept depends on non-methane-dependent oxidation processes. The model was tested with eddy covariance CO2 and CH4 emission rates at Bluff Road Landfill in Lincoln Nebraska. It predicted zero oxidation rate in the northern portion of this landfill where a membrane and vents were present. The zero oxidation rate was expected because there would be little opportunity for methane to encounter oxidizing conditions before leaving the vents. We also applied the model at the Turkey Run Landfill in Georgia to estimate the CH4 oxidation rate over a one year period. In contrast to Bluff Road Landfill, the Turkey Run Landfill did not have a membrane or vents. Instead, methane produced in the landfill had to diffuse through a 0.5 m soil cap before release to the atmosphere. We observed evidence for methane oxidation ranging from about 18% to above 60% depending upon the age of deposited waste material. The model will be briefly described, and results from the two contrasting landfills will be discussed in this presentation.

  16. SiteChar. Characterisation of European CO2 storage. Deliverable D8.2. Trust building and raising public awareness

    Energy Technology Data Exchange (ETDEWEB)

    Brunsting, S.; Pol, M.; Mastop, E.A. [ECN Policy Studies, Energy research Centre of the Netherlands ECN, Amsterdam (Netherlands); Kaiser, M.; Zimmer, R. [Unabhaengiges Institut fuer Umweltfragen UfU, Berlin (Germany); Shackley, S.; Mabon, L.; Howell, R. [Scottish Carbon Capture and Storage SCCS, Edinburg, Scotland (United Kingdom)


    At local level, public support has proven crucial to the implementation of CO2 capture and storage (CCS) demonstration projects. Whereas no method exists to guarantee public acceptability of any project, a constructive stakeholder and community engagement process does increase the likelihood thereof. This deliverable is a follow-up to deliverable D8.1 'Social site characterisation'. Social site characterisation can be used as an instrument to explore, plan and evaluate a process of active and constructive local stakeholder and citizen engagement in a prospective CCS project as a parallel activity to technical site characterisation. It serves as an analytical tool to describe the local social circumstances in the area and to design and evaluate stakeholder and community engagement efforts with the aims of building trust and raising public awareness. Using results from the social site characterisation of the area, the present deliverable focuses on the second purpose. It presents results from public engagement activities designed to raise public awareness and inform public opinion of a prospective CCS site in Poland (onshore) and the UK (offshore): focus conferences. Furthermore, by initiating an enhanced cooperation in planning of new storage sites between project developers, authorities and the local public, focus conferences aim to serve as a 'hinge' between social site characterisation as a research effort and application to real-life project settings. The focus conferences are part of a range of public engagement activities including the setup of public information websites on generic and site-specific CCS, information meetings. A second survey eventually shall evaluate the results of the public engagement activities. The aim of the focus conferences was to raise public awareness and assist public opinion forming processes of a prospective CCS site in Poland (onshore) and the UK (offshore). At the same time, it aimed to present and test a

  17. On scale and magnitude of pressure build-up induced by large-scale geologic storage of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Q.; Birkholzer, J. T.


    The scale and magnitude of pressure perturbation and brine migration induced by geologic carbon sequestration is discussed assuming a full-scale deployment scenario in which enough CO{sub 2} is captured and stored to make relevant contributions to global climate change mitigation. In this scenario, the volumetric rates and cumulative volumes of CO{sub 2} injection would be comparable to or higher than those related to existing deep-subsurface injection and extraction activities, such as oil production. Large-scale pressure build-up in response to the injection may limit the dynamic storage capacity of suitable formations, because over-pressurization may fracture the caprock, may drive CO{sub 2}/brine leakage through localized pathways, and may cause induced seismicity. On the other hand, laterally extensive sedimentary basins may be less affected by such limitations because (i) local pressure effects are moderated by pressure propagation and brine displacement into regions far away from the CO{sub 2} storage domain; and (ii) diffuse and/or localized brine migration into overlying and underlying formations allows for pressure bleed-off in the vertical direction. A quick analytical estimate of the extent of pressure build-up induced by industrial-scale CO{sub 2} storage projects is presented. Also discussed are pressure perturbation and attenuation effects simulated for two representative sedimentary basins in the USA: the laterally extensive Illinois Basin and the partially compartmentalized southern San Joaquin Basin in California. These studies show that the limiting effect of pressure build-up on dynamic storage capacity is not as significant as suggested by Ehlig-Economides and Economides, who considered closed systems without any attenuation effects.

  18. Four years of experience with a permanent seismic monitoring array at the Ketzin CO2 storage pilot site

    NARCIS (Netherlands)

    Paap, B.F.; Verdel, A.R.; Meekes, J.A.C.; Steeghs, T.P.H.; Vandeweijer, V.P.; Neele, F.P.


    CO2 was injected into a saline aquifer near the town of Ketzin in Germany from July 2008 to August 2013. To monitor CO2- migration close to the injection well, TNO installed a fixed 2D seismic array of 120 meters length in 2009, with 3- component (3- C) geophones at the surface, 4-component

  19. Productivity and CO2 exchange of Great Plains ecoregions. I. Shortgrass steppe: Flux tower estimates (United States)

    Gilmanov, Tagir G.; Morgan, Jack A.; Hanan, Niall P.; Wylie, Bruce K.; Rajan, Nithya; Smith, David P.; Howard, Daniel M.


    The shortgrass steppe (SGS) occupies the southwestern part of the Great Plains. Half of the land is cultivated, but significant areas remain under natural vegetation. Despite previous studies of the SGS carbon cycle, not all aspects have been completely addressed, including gross productivity, ecosystem respiration, and ecophysiological parameters. Our analysis of 1998 − 2007 flux tower measurements at five Bowen ratio–energy balance (BREB) and three eddy covariance (EC) sites characterized seasonal and interannual variability of gross photosynthesis and ecosystem respiration. Identification of the nonrectangular hyperbolic equation for the diurnal CO2 exchange, with vapor pressure deficit (VPD) limitation and exponential temperature response, quantified quantum yield α, photosynthetic capacity Amax, and respiration rate rd with variation ranges (19 \\production from − 900 to + 700 g CO2 m− 2 yr− 1, indicating that SGS may switch from a sink to a source depending on weather. Comparison of the 2004 − 2006 measurements at two BREB and two parallel EC flux towers located at comparable SGS sites showed moderately higher photosynthesis, lower respiration, and higher net production at the BREB than EC sites. However, the difference was not related only to methodologies, as the normalized difference vegetation index at the BREB sites was higher than at the EC sites. Overall magnitudes and seasonal patterns at the BREB and the EC sites during the 3-yr period were similar, with trajectories within the ± 1.5 standard deviation around the mean of the four sites and mostly reflecting the effects of meteorology.

  20. Line-averaging measurement methods to estimate the gap in the CO2 balance closure - possibilities, challenges, and uncertainties (United States)

    Ziemann, Astrid; Starke, Manuela; Schütze, Claudia


    An imbalance of surface energy fluxes using the eddy covariance (EC) method is observed in global measurement networks although all necessary corrections and conversions are applied to the raw data. Mainly during nighttime, advection can occur, resulting in a closing gap that consequently should also affect the CO2 balances. There is the crucial need for representative concentration and wind data to measure advective fluxes. Ground-based remote sensing techniques are an ideal tool as they provide the spatially representative CO2 concentration together with wind components within the same voxel structure. For this purpose, the presented SQuAd (Spatially resolved Quantification of the Advection influence on the balance closure of greenhouse gases) approach applies an integrated method combination of acoustic and optical remote sensing. The innovative combination of acoustic travel-time tomography (A-TOM) and open-path Fourier-transform infrared spectroscopy (OP-FTIR) will enable an upscaling and enhancement of EC measurements. OP-FTIR instrumentation offers the significant advantage of real-time simultaneous measurements of line-averaged concentrations for CO2 and other greenhouse gases (GHGs). A-TOM is a scalable method to remotely resolve 3-D wind and temperature fields. The paper will give an overview about the proposed SQuAd approach and first results of experimental tests at the FLUXNET site Grillenburg in Germany. Preliminary results of the comprehensive experiments reveal a mean nighttime horizontal advection of CO2 of about 10 µmol m-2 s-1 estimated by the spatially integrating and representative SQuAd method. Additionally, uncertainties in determining CO2 concentrations using passive OP-FTIR and wind speed applying A-TOM are systematically quantified. The maximum uncertainty for CO2 concentration was estimated due to environmental parameters, instrumental characteristics, and retrieval procedure with a total amount of approximately 30 % for a single

  1. Line-averaging measurement methods to estimate the gap in the CO2 balance closure – possibilities, challenges, and uncertainties

    Directory of Open Access Journals (Sweden)

    A. Ziemann


    Full Text Available An imbalance of surface energy fluxes using the eddy covariance (EC method is observed in global measurement networks although all necessary corrections and conversions are applied to the raw data. Mainly during nighttime, advection can occur, resulting in a closing gap that consequently should also affect the CO2 balances. There is the crucial need for representative concentration and wind data to measure advective fluxes. Ground-based remote sensing techniques are an ideal tool as they provide the spatially representative CO2 concentration together with wind components within the same voxel structure. For this purpose, the presented SQuAd (Spatially resolved Quantification of the Advection influence on the balance closure of greenhouse gases approach applies an integrated method combination of acoustic and optical remote sensing. The innovative combination of acoustic travel-time tomography (A-TOM and open-path Fourier-transform infrared spectroscopy (OP-FTIR will enable an upscaling and enhancement of EC measurements. OP-FTIR instrumentation offers the significant advantage of real-time simultaneous measurements of line-averaged concentrations for CO2 and other greenhouse gases (GHGs. A-TOM is a scalable method to remotely resolve 3-D wind and temperature fields. The paper will give an overview about the proposed SQuAd approach and first results of experimental tests at the FLUXNET site Grillenburg in Germany. Preliminary results of the comprehensive experiments reveal a mean nighttime horizontal advection of CO2 of about 10 µmol m−2 s−1 estimated by the spatially integrating and representative SQuAd method. Additionally, uncertainties in determining CO2 concentrations using passive OP-FTIR and wind speed applying A-TOM are systematically quantified. The maximum uncertainty for CO2 concentration was estimated due to environmental parameters, instrumental characteristics, and retrieval procedure with a total amount of approximately

  2. Predicting the impacts of CO2 leakage from subseabed storage: effects of metal accumulation and toxicity on the model benthic organism Ruditapes philippinarum. (United States)

    Rodríguez-Romero, Araceli; Jiménez-Tenorio, Natalia; Basallote, M Dolores; De Orte, Manoela R; Blasco, Julián; Riba, Inmaculada


    The urgent need to minimize the potential harm deriving from global climate change and ocean acidification has led governmental decision-makers and scientists to explore and study new strategies for reducing the levels of anthropogenic CO2. One of the mitigation measures proposed for reducing the concentration of atmospheric CO2 is the capture and storage of this gas in subseabed geological formations; this proposal is generating considerable international interest. The main risk associated with this option is the leakage of retained CO2, which could cause serious environmental perturbations, particularly acidification, in marine ecosystems. The study reported is aimed at quantifying the effects of acidification derived from CO2 leakage on marine organisms. To this end, a lab-scale experiment involving direct release of CO2 through marine sediment was conducted using Ruditapes philippinarum as a model benthic organism. For 10 days bivalves were exposed to 3 sediment samples with different physicochemical characteristics and at pre-established pH conditions (8.0-6.1). End points measured were: survival, burrowing activity, histopathological lesions, and metal accumulation (Fe, Al, Mn, Cu, and Zn) in whole body. Correlations analyses indicated highly significant associations (P metal concentrations in tissues. Further research to understand and predict the biological and economic implications for coastal ecosystems deriving from acidification by CO2 leakages is urgently needed.

  3. CO2NNIE

    DEFF Research Database (Denmark)

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


    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....

  4. Reactivity of sandstone and siltstone samples from the Ketzin pilot CO2 storage site-Laboratory experiments and reactive geochemical modeling


    Sebastian Fischer; Axel Liebscher; Marco De Lucia; L. Hecht; Ketzin Team and the


    To evaluate mineralogical-geochemical changes within the reservoir of the Ketzin pilot CO2 storage site in Brandenburg, Germany, two sets of laboratory experiments on sandstone and siltstone samples from the Stuttgart Formation have been performed. Samples were exposed to synthetic brine and pure CO2 at experimental conditions and run durations of 5.5 MPa/40 °C/40 months for sandstone and 7.5 MPa/40 °C/6 months for siltstone samples, respectively. Mineralogical changes in both sets of experim...

  5. Uncertainty in projected climate change caused by methodological discrepancy in estimating CO2 emissions from fossil fuel combustion (United States)

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


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

  6. A Panel Estimation of the Relationship Between Trade Liberalization, Economic Growth and CO2 Emissions in BRICS Countries

    Directory of Open Access Journals (Sweden)

    Mehrara Mohsen


    Full Text Available In the last few years, several studies have found an inverted-U relationship between per capita income and environmental degradation. This relationship, known as the environmental Kuznets curve (EKC, suggests that environmental degradation increases in the early stages of growth, but it eventually decreases as income exceeds a threshold level. However, this paper investigation relationship between per capita CO2 emission, growth economics and trade liberalization based on econometric techniques of unit root test, co-integration and a panel data set during the period 1960-1996 for BRICS countries. Data properties were analyzed to determine their stationarity using the LLC , IPS , ADF and PP unit root tests which indicated that the series are I(1. We find a cointegration relationship between per capita CO2 emission, growth economics and trade liberalization by applying Kao panel cointegration test. The evidence indi\tcates that in the long-run trade liberalization has a positive significant impact on CO2 emissions and impact of trade liberalization on emissions growth depends on the level of income Our findings suggest that there is a quadratic relationship between relationship between real GDP and CO2 emissions for the region as a whole. The estimated long-run coefficients of real GDP and its square satisfy the EKC hypothesis in all of studied countries. Our estimation shows that the inflection point or optimal point real GDP per capita is about 5269.4 dollars. The results show that on average, sample countries are on the positive side of the inverted U curve. The turning points are very low in some cases and very high in other cases, hence providing poor evidence in support of the EKC hypothesis. Thus, our findings suggest that all BRICS countries need to sacrifice economic growth to decrease their emission levels

  7. Estimating the CO2 mitigation potential of horizontal Ground Source Heat Pumps in the UK (United States)

    Garcia-Gonzalez, R.; Verhoef, A.; Vidale, P. L.; Gan, G.; Chong, A.; Clark, D.


    By 2020, the UK will need to generate 15% of its energy from renewables to meet our contribution to the EU renewable energy target. Heating and cooling systems of buildings account for 30%-50% of the global energy consumption; thus, alternative low-carbon technologies such as horizontal Ground Couple Heat Pumps (GCHPs) can contribute to the reduction of anthropogenic CO2 emissions. Horizontal GCHPs currently represent a small fraction of the total energy generation in the UK. However, the fact that semi-detached and detached dwellings represent approximately 40% of the total housing stocks in the UK could make the widespread implementation of this technology particularly attractive in the UK and so could significantly increase its renewable energy generation potential. Using a simulation model, we analysed the dynamic interactions between the environment, the horizontal GCHP heat exchanger and typical UK dwellings, as well as their combined effect on heat pump performance and CO2 mitigation potential. For this purpose, a land surface model (JULES, Joint UK Land Environment Simulator), which calculates coupled soil heat and water fluxes, was combined with a heat extraction model. The analyses took into account the spatio-temporal variability of soil properties (thermal and hydraulic) and meteorological variables, as well as different horizontal GCHP configurations and a variety of building loads and heat demands. Sensitivity tests were performed for four sites in the UK with different climate and soil properties. Our results show that an installation depth of 1.0m would give us higher heat extractions rates, however it would be preferable to install the pipes slightly deeper to avoid the seasonal influence of variable meteorological conditions. A value of 1.5m for the spacing between coils (S) for a slinky configuration type is recommended to avoid thermal disturbances between neighbouring coils. We also found that for larger values of the spacing between the coils

  8. Estimating regional fluxes of CO2 and CH4 using space-borne observations of XCH4: XCO2

    Directory of Open Access Journals (Sweden)

    A. Fraser


    Full Text Available We use the GEOS-Chem global 3-D atmospheric chemistry transport model to interpret XCH4:XCO2 column ratios retrieved from the Japanese Greenhouse Gases Observing Satellite (GOSAT. The advantage of these data over CO2 and CH4 columns retrieved independently using a full physics optimal estimation algorithm is that they are less prone to scattering-related regional biases. We show that the model is able to reproduce observed global and regional spatial (mean bias =0.7% and temporal variations (global r2=0.92 of this ratio with a model bias 2 and CH4 that are typically 6 months out of phase, which may reduce the sensitivity of the ratio to changes in either gas. To simultaneously estimate fluxes of CO2 and CH4 we use a maximum likelihood estimation approach. We use two approaches to resolve independent flux estimates of these two gases using GOSAT observations of XCH4:XCO2: (1 the a priori error covariance between CO2 and CH4 describing common source from biomass burning; and (2 also fitting independent surface atmospheric measurements of CH4 and CO2 mole fraction that provide additional constraints, improving the effectiveness of the observed GOSAT ratio to constrain flux estimates. We demonstrate the impact of these two approaches using numerical experiments. A posteriori flux estimates inferred using only the GOSAT ratios and taking advantage of the error covariance due to biomass burning are not consistent with the true fluxes in our experiments, as the inversion system cannot judge which species' fluxes to adjust. This reflects the weak dependence of XCH4:XCO2 on biomass burning. We find that adding the surface data effectively provides an "anchor" to the inversion that dramatically improves the ability of the GOSAT ratios to infer both CH4 and CO2 fluxes. We show that the regional flux estimates inferred from GOSAT XCH4:XCO2 ratios together with the surface mole fraction data during 2010 are typically consistent with or better than the

  9. Soil carbon and nitrogen cycling and storage throughout the soil profile in a sweetgum plantation after 11 years of CO2-enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Iversen, Colleen M [ORNL; Keller, Dr. Jason K. [Chapman University; Garten Jr, Charles T [ORNL; Norby, Richard J [ORNL


    Increased partitioning of carbon (C) to fine roots under elevated [CO2], especially deep in the soil profile, could alter soil C and nitrogen (N) cycling in forests. After more than 11 years of free-Air CO2 enrichment in a Liquidambar styraciflua L. (sweetgum) plantation in Oak Ridge, TN, USA, greater inputs of fine roots resulted in the incorporation of new C (i.e., C with a depleted 13C) into root-derived particulate organic matter (POM) pools to 90-cm depth. Even though production in the sweetgum stand was limited by soil N availability, soil C and N content increased over time, and were greater throughout the soil profile under elevated [CO2] at the conclusion of the experiment. However, greater C inputs under elevated [CO2] did not result in increased net N immobilization or C mineralization rates in long-term laboratory incubations, and did not appear to prime the decomposition of older SOM. The 13CO2 of the C mineralized from the incubated soil closely tracked the 13C of the labile POM pool in the elevated [CO2] treatment, especially in shallower soil, and did not indicate the decomposition of older (i.e., pre-experiment) SOM. While potential C mineralization rates were positively and linearly related to total soil organic matter (SOM) C content in the top 30 cm of soil, this relationship did not hold in deeper soil. Taken together with an increased mean residence time of C in deeper soil pools, these findings indicate that C inputs from relatively deep roots under elevated [CO2] may have increased potential for long-term storage. Expanded representation of biogeochemical cycling throughout the soil profile may improve model projections of future forest responses to rising atmospheric [CO2].

  10. Gas-water-rock interactions in Frio Formation following CO2 injection: Implications for the storage of greenhouse gases in sedimentary basins (United States)

    Kharaka, Yousif K.; Cole, David R.; Hovorka, Susan D.; Gunter, W.D.; Knauss, Kevin G.; Freifeild, Barry M.


    To investigate the potential for the geologic storage of CO2 in saline sedimentary aquifers, 1600 t of CO2 were injected at 1500 m depth into a 24-m-thick sandstone section of the Frio Formation, a regional brine and oil reservoir in the U.S. Gulf Coast. Fluid samples obtained from the injection and observation wells before CO2 injection showed a Na-Ca-Cl–type brine with 93,000 mg/L total dissolved solids (TDS) at near saturation with CH4 at reservoir conditions. Following CO2 breakthrough, samples showed sharp drops in pH (6.5–5.7), pronounced increases in alkalinity (100–3000 mg/L as HCO3) and Fe (30–1100 mg/L), and significant shifts in the isotopic compositions of H2O, dissolved inorganic carbon (DIC), and CH4. Geochemical modeling indicates that brine pH would have dropped lower but for the buffering by dissolution of carbonate and iron oxyhydroxides. This rapid dissolution of carbonate and other minerals could ultimately create pathways in the rock seals or well cements for CO2 and brine leakage. Dissolution of minerals, especially iron oxyhydroxides, could mobilize toxic trace metals and, where residual oil or suitable organics are present, the injected CO2 could also mobilize toxic organic compounds. Environmental impacts could be major if large brine volumes with mobilized toxic metals and organics migrated into potable groundwater. The δ18O values for brine and CO2 samples indicate that supercritical CO2 comprises ∼50% of pore-fluid volume ∼6 mo after the end of injection. Postinjection sampling, coupled with geochemical modeling, indicates that the brine gradually will return to its preinjection composition.

  11. Public Perception of Carbon Capture and Storage. Qualitative Study Results; Percepcion Publica de la captura y almacenamiento de CO2. Resultados de un Estudio Cualitativo

    Energy Technology Data Exchange (ETDEWEB)

    Sola, R.; Sala, R.; Oltra, C.


    In recent years, public perception and acceptance of Carbon Capture and Storage has become a key issue for research as technological projects have been initiated in USA, Canada and Europe. It has been considered that public opposition could be an important barrier for technological deployment. This report is part of the sub project Acceptability and Governance of CO2 storage processes, started in 2005 as a part of the technological project Advanced technologies of CO2 generation, capture and storage. The study is based on the application of focus groups with lay people. This qualitative social research technique was applied to get a deeper knowledge of the elements influencing the public acceptability of CO2 storage sites. Results indicate that there exists a low level of awareness about the technology among participants. After providing some information about the technology, the initial reaction stays between rejection and ambivalence. A reluctant acceptance appears when significant importance is given to the perceived benefits. The perception of risk from climate change plays an essential role. (Author) 25 refs.

  12. Experimental investigations and geochemical modelling of site-specific fluid-fluid and fluid-rock interactions in underground storage of CO2/H2/CH4 mixtures: the H2STORE project (United States)

    De Lucia, Marco; Pilz, Peter


    Underground gas storage is increasingly regarded as a technically viable option for meeting the energy demand and environmental targets of many industrialized countries. Besides the long-term CO2 sequestration, energy can be chemically stored in form of CO2/CH4/H2 mixtures, for example resulting from excess wind energy. A precise estimation of the impact of such gas mixtures on the mineralogical, geochemical and petrophysical properties of specific reservoirs and caprocks is crucial for site selection and optimization of storage depth. Underground gas storage is increasingly regarded as a technically viable option for meeting environmental targets and the energy demand through storage in form of H2 or CH4, i.e. resulting from excess wind energy. Gas storage in salt caverns is nowadays a mature technology; in regions where favorable geologic structures such as salt diapires are not available, however, gas storage can only be implemented in porous media such as depleted gas and oil reservoirs or suitable saline aquifers. In such settings, a significant amount of in-situ gas components such as CO2, CH4 (and N2) will always be present, making the CO2/CH4/H2 system of particular interest. A precise estimation of the impact of their gas mixtures on the mineralogical, geochemical and petrophysical properties of specific reservoirs and caprocks is therefore crucial for site selection and optimization of storage depth. In the framework of the collaborative research project H2STORE, the feasibility of industrial-scale gas storage in porous media in several potential siliciclastic depleted gas and oil reservoirs or suitable saline aquifers is being investigated by means of experiments and modelling on actual core materials from the evaluated sites. Among them are the Altmark depleted gas reservoir in Saxony-Anhalt and the Ketzin pilot site for CO2 storage in Brandenburg (Germany). Further sites are located in the Molasse basin in South Germany and Austria. In particular, two

  13. CO2 uptake and ecophysiological parameters of the grain crops of midcontinent North America: estimates from flux tower measurements (United States)

    Gilmanov, Tagir; Wylie, Bruce; Tieszen, Larry; Meyers, Tilden P.; Baron, Vern S.; Bernacchi, Carl J.; Billesbach, David P.; Burba, George G.; Fischer, Marc L.; Glenn, Aaron J.; Hanan, Niall P.; Hatfield, Jerry L.; Heuer, Mark W.; Hollinger, Steven E.; Howard, Daniel M.; Matamala, Roser; Prueger, John H.; Tenuta, Mario; Young, David G.


    We analyzed net CO2 exchange data from 13 flux tower sites with 27 site-years of measurements over maize and wheat fields across midcontinent North America. A numerically robust “light-soil temperature-VPD”-based method was used to partition the data into photosynthetic assimilation and ecosystem respiration components. Year-round ecosystem-scale ecophysiological parameters of apparent quantum yield, photosynthetic capacity, convexity of the light response, respiration rate parameters, ecological light-use efficiency, and the curvature of the VPD-response of photosynthesis for maize and wheat crops were numerically identified and interpolated/extrapolated. This allowed us to gap-fill CO2 exchange components and calculate annual totals and budgets. VPD-limitation of photosynthesis was systematically observed in grain crops of the region (occurring from 20 to 120 days during the growing season, depending on site and year), determined by the VPD regime and the numerical value of the curvature parameter of the photosynthesis-VPD-response, σVPD. In 78% of the 27 site-years of observations, annual gross photosynthesis in these crops significantly exceeded ecosystem respiration, resulting in a net ecosystem production of up to 2100 g CO2 m−2 year−1. The measurement-based photosynthesis, respiration, and net ecosystem production data, as well as the estimates of the ecophysiological parameters, provide an empirical basis for parameterization and validation of mechanistic models of grain crop production in this economically and ecologically important region of North America.

  14. Temperature and atmospheric CO2 concentration estimates through the PETM using triple oxygen isotope analysis of mammalian bioapatite. (United States)

    Gehler, Alexander; Gingerich, Philip D; Pack, Andreas


    The Paleocene-Eocene Thermal Maximum (PETM) is a remarkable climatic and environmental event that occurred 56 Ma ago and has importance for understanding possible future climate change. The Paleocene-Eocene transition is marked by a rapid temperature rise contemporaneous with a large negative carbon isotope excursion (CIE). Both the temperature and the isotopic excursion are well-documented by terrestrial and marine proxies. The CIE was the result of a massive release of carbon into the atmosphere. However, the carbon source and quantities of CO2 and CH4 greenhouse gases that contributed to global warming are poorly constrained and highly debated. Here we combine an established oxygen isotope paleothermometer with a newly developed triple oxygen isotope paleo-CO2 barometer. We attempt to quantify the source of greenhouse gases released during the Paleocene-Eocene transition by analyzing bioapatite of terrestrial mammals. Our results are consistent with previous estimates of PETM temperature change and suggest that not only CO2 but also massive release of seabed methane was the driver for CIE and PETM.

  15. Efficient Bayesian updating with PCE-based particle filters based on polynomial chaos expansion and CO2 storage (United States)

    Oladyshkin, S.; Class, H.; Helmig, R.; Nowak, W.


    Underground flow systems, such as oil or gas reservoirs and CO2 storage sites, are an important and challenging class of complex dynamic systems. Lacking information about distributed systems properties (such as porosity, permeability,...) leads to model uncertainties up to a level where quantification of uncertainties may become the dominant question in application tasks. History matching to past production data becomes an extremely important issue in order to improve the confidence of prediction. The accuracy of history matching depends on the quality of the established physical model (including, e.g. seismic, geological and hydrodynamic characteristics, fluid properties etc). The history matching procedure itself is very time consuming from the computational point of view. Even one single forward deterministic simulation may require parallel high-performance computing. This fact makes a brute-force non-linear optimization approach not feasible, especially for large-scale simulations. We present a novel framework for history matching which takes into consideration the nonlinearity of the model and of inversion, and provides a cheap but highly accurate tool for reducing prediction uncertainty. We propose an advanced framework for history matching based on the polynomial chaos expansion (PCE). Our framework reduces complex reservoir models and consists of two main steps. In step one, the original model is projected onto a so-called integrative response surface via very recent PCE technique. This projection is totally non-intrusive (following a probabilistic collocation method) and optimally constructed for available reservoir data at the prior stage of Bayesian updating. The integrative response surface keeps the nonlinearity of the initial model at high order and incorporates all suitable parameters, such as uncertain parameters (porosity, permeability etc.) and design or control variables (injection rate, depth etc.). Technically, the computational costs for

  16. Estimation of the oceanic pCO2 in the North Atlantic from VOS lines in-situ measurements: parameters needed to generate seasonally mean maps

    Directory of Open Access Journals (Sweden)

    C. Jamet


    Full Text Available Automated instruments on board Volunteer Observing Ships (VOS have provided high-frequency pCO2 measurements over basin-wide regions for a decade or so. In order to estimate regional air-sea CO2 fluxes, it is necessary to interpolate between in-situ measurements to obtain maps of the marine pCO2. Such an interpolation remains, however, a difficult task because VOS lines are too distant from each other to capture the high pCO2 variability. Relevant physical parameters available at large scale are thus necessary to serve as a guide to estimate the pCO2 values between the VOS lines. Satellites do not measure pCO2 but they give access to parameters related to the processes that control its variability, such as sea surface temperature (SST. In this paper we developed a method to compute pCO2 maps using satellite data (SST and CHL, the chlorophyll concentration, combined with a climatology of the mixed-layer depth (MLD. Using 15 401 measurements of surface pCO2 acquired in the North Atlantic between UK and Jamaica, between June 1994 and August 1995, we show that the parameterization of pCO2 as a function of SST, CHL and MLD yields more realistic pCO2 values than parameterizations that have been widely used in the past, based on SST, latitude, longitude or SST only. This parameterization was then used to generate seasonal maps of pCO2 over the North Atlantic. Results show that our approach yields the best marine pCO2 estimates, both in terms of absolute accuracy, when compared with an independent data set, and of geographical patterns, when compared to the climatology of Takahashi et al. (2002. This suggests that monitoring the seasonal variability of pCO2 over basin-wide regions is possible, provided that sufficient VOS lines are available.

  17. On-road emissions of CO, CO2 and NOX from four wheeler and emission estimates for Delhi. (United States)

    Jaiprakash; Habib, Gazala; Kumar, Anil; Sharma, Akash; Haider, Minza


    This study presents the emission factor of gaseous pollutants (CO, CO2, and NOX) from on-road tailpipe measurement of 14 passenger cars of different types of fuel and vintage. The trolley equipped with stainless steel duct, vane probe velocity meter, flue gas analyzer, Nondispersive infra red (NDIR) CO2 analyzer, temperature, and relative humidity (RH) sensors was connected to the vehicle using a towing system. Lower CO and higher NOX emissions were observed from new diesel cars (post 2010) compared to old cars (post 2005), which implied that new technological advancement in diesel fueled passenger cars to reduce CO emission is a successful venture, however, the use of turbo charger in diesel cars to achieve high temperature combustion might have resulted in increased NOX emissions. Based on the measured emission factors (g/kg), and fuel consumption (kg), the average and 95% confidence interval (CI) bound estimates of CO, CO2, and NOX from four wheeler (4W) in Delhi for the year 2012 were 15.7 (1.4-37.1) , 6234 (386-12,252) , and 30.4 (0.0-103) Gg/year, respectively. The contribution of diesel, gasoline and compressed natural gas (CNG) to total CO, CO2 and NOX emissions were 7:84:9, 50:48:2 and 58:41:1 respectively. The present work indicated that the age and the maintenance of vehicle both are important factors in emission assessment therefore, more systematic repetitive measurements covering wide range of vehicles of different age groups, engine capacity, and maintenance level is needed for refining the emission factors with CI. Copyright © 2016. Published by Elsevier B.V.

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

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


    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.

  19. Increased forest carbon storage with increased atmospheric CO2 despite nitrogen limitation: a game-theoretic allocation model for trees in competition for nitrogen and light. (United States)

    Dybzinski, Ray; Farrior, Caroline E; Pacala, Stephen W


    Changes in resource availability often cause competitively driven changes in tree allocation to foliage, wood, and fine roots, either via plastic changes within individuals or through turnover of individuals with differing strategies. Here, we investigate how optimally competitive tree allocation should change in response to elevated atmospheric CO2 along a gradient of nitrogen and light availability, together with how those changes should affect carbon storage in living biomass. We present a physiologically-based forest model that includes the primary functions of wood and nitrogen. From a tree's perspective, wood is an offensive and defensive weapon used against neighbors in competition for light. From a biogeochemical perspective, wood is the primary living reservoir of stored carbon. Nitrogen constitutes a tree's photosynthetic machinery and the support systems for that machinery, and its limited availability thus reduces a tree's ability to fix carbon. This model has been previously successful in predicting allocation to foliage, wood, and fine roots along natural productivity gradients. Using game theory, we solve the model for competitively optimal foliage, wood, and fine root allocation strategies for trees in competition for nitrogen and light as a function of CO2 and nitrogen mineralization rate. Instead of down-regulating under nitrogen limitation, carbon storage under elevated CO2 relative to carbon storage at ambient CO2 is approximately independent of the nitrogen mineralization rate. This surprising prediction is a consequence of both increased competition for nitrogen driving increased fine root biomass and increased competition for light driving increased allocation to wood under elevated CO2 . © 2014 John Wiley & Sons Ltd.

  20. Final Report on "Rising CO2 and Long-term Carbon Storage in Terrestrial Ecosystems: An Empirical Carbon Budget Validation"

    Energy Technology Data Exchange (ETDEWEB)

    J. Patrick Megonigal; Bert G. Drake


    The primary goal of this report is to report the results of Grant DE-FG02-97ER62458, which began in 1997 as Grant DOE-98-59-MP-4 funded through the TECO program. However, this project has a longer history because DOE also funded this study from its inception in 1985 through 1997. The original grant was focused on plant responses to elevated CO2 in an intact ecosystem, while the latter grant was focused on belowground responses. Here we summarize the major findings across the 25 years this study has operated, and note that the experiment will continue to run through 2020 with NSF support. The major conclusions of the study to date are: (1 Elevated CO2 stimulated plant productivity in the C3 plant community by ~30% during the 25 year study. The magnitude of the increase in productivity varied interannually and was sometime absent altogether. There is some evidence of down-regulation at the ecosystem level across the 25 year record that may be due to interactions with other factors such as sea-level rise or long-term changes in N supply; (2) Elevated CO2 stimulated C4 productivity by <10%, perhaps due to more efficient water use, but C3 plants at elevated CO2 did not displace C4 plants as predicted; (3) Increased primary production caused a general stimulation of microbial processes, but there were both increases and decreases in activity depending on the specific organisms considered. An increase in methanogenesis and methane emissions implies elevated CO2 may amplify radiative forcing in the case of wetland ecosystems; (4) Elevated CO2 stimulated soil carbon sequestration in the form of an increase in elevation. The increase in elevation is 50-100% of the increase in net ecosystem production caused by elevated CO2 (still under analysis). The increase in soil elevation suggests the elevated CO2 may have a positive outcome for the ability of coastal wetlands to persist despite accelerated sea level rise; (5) Crossing elevated CO2 with elevated N causes the elevated CO

  1. Estimating Asian terrestrial carbon fluxes from CONTRAIL aircraft and surface CO2 observations for the period 2006 to 2010 (United States)

    Zhang, H. F.; Chen, B. Z.; van der Laan-Luijkx, I. T.; Machida, T.; Matsueda, H.; Sawa, Y.; Fukuyama, Y.; Labuschagne, C.; Langenfelds, R.; van der Schoot, M.; Xu, G.; Yan, J. W.; Zhou, L. X.; Tans, P. P.; Peters, W.


    Current estimates of the terrestrial carbon fluxes in Asia ("Asia" refers to lands as far west as the Urals and is divided into Boreal Eurasia, Temperate Eurasia and tropical Asia based on TransCom regions) show large uncertainties particularly in the boreal and mid-latitudes and in China. In this paper, we present an updated carbon flux estimate for Asia by introducing aircraft CO2 measurements from the CONTRAIL (Comprehensive Observation Network for Trace gases by Airline) program into an inversion modeling system based on the CarbonTracker framework. We estimated the averaged annual total Asian terrestrial land CO2 sink was about -1.56 Pg C yr-1 over the period 2006-2010, which offsets about one-third of the fossil fuel emission from Asia (+4.15 Pg C yr-1). The uncertainty of the terrestrial uptake estimate was derived from a set of sensitivity tests and ranged from -1.07 to -1.80 Pg C yr-1, comparable to the formal Gaussian error of ±1.18 Pg C yr-1 (1-sigma). The largest sink was found in forests, predominantly in coniferous forests (-0.64 Pg C yr-1) and mixed forests (-0.14 Pg C yr-1); and the second and third large carbon sinks were found in grass/shrub lands and crop lands, accounting for -0.44 Pg C yr-1 and -0.20 Pg C yr-1, respectively. The peak-to-peak amplitude of inter-annual variability (IAV) was 0.57 Pg C yr-1 ranging from -1.71 Pg C yr-1 to -2.28 Pg C yr-1. The IAV analysis reveals that the Asian CO2 sink was sensitive to climate variations, with the lowest uptake in 2010 concurrent with summer flood/autumn drought and the largest CO2 sink in 2009 owing to favorable temperature and plentiful precipitation conditions. We also found the inclusion of the CONTRAIL data in the inversion modeling system reduced the uncertainty by 11% over the whole Asian region, with a large reduction in the southeast of Boreal Eurasia, southeast of Temperate Eurasia and most Tropical Asian areas.

  2. Biochemical Basis of CO2-Related Internal Browning Disorders in Pears (Pyrus communis L. cv. Rocha) during Long-Term Storage. (United States)

    Deuchande, Teresa; Larrigaudière, Christian; Giné-Bordonaba, Jordi; Carvalho, Susana M P; Vasconcelos, Marta W


    This study aimed at understanding the biochemical basis of internal browning disorders (IBDs) in 'Rocha' pear. For this purpose, the effects of storage under normal controlled atmosphere (CA) (3 kPa of O2 + 0.5 kPa of CO2) and IBD-inducing CA (1 kPa of O2 + 10 kPa of CO2) on the antioxidant and fermentative metabolisms and polyphenol oxidase (PPO) activity and phenolics concentration were studied. The higher IBD incidence in high CO2-stored fruits was positively correlated with fermentative metabolites and negatively with ascorbate and H2O2 concentrations, and it was linked to PPO activation. These results indicate that both the antioxidant and fermentative metabolisms are involved in the occurrence of IBD in 'Rocha' pear. From the integration of the biochemical and enzymatic data, a schematic model illustrating the effects of high CO2 and low O2 in 'Rocha' pears during long-term storage was constructed.

  3. Assessing drilling mud and technical fluid contamination in rock core and brine samples intended for microbiological monitoring at the CO2 storage site in Ketzin using fluorescent dye tracers


    M. Wandrey; Daria Morozova; M. Zettlitzer; Hilke Würdemann; CO2SINK Group


    To test the injection behaviour of CO2 into brine-saturated rock and to evaluate the dependence of geophysical properties on CO2 injection, flow and exposure experiments with brine and CO2 were performed on sandstone samples of the Stuttgart Formation representing potential reservoir rocks for CO2 storage. The sandstone samples studied are generally fine-grained with porosities between 17 and 32% and permeabilities between 1 and 100 mD. Additional batch experiments were performed to predict t...

  4. "Supergreen" Renewables: Integration of Mineral Weathering Into Renewable Energy Production for Air CO2 Removal and Storage as Ocean Alkalinity (United States)

    Rau, G. H.; Carroll, S.; Ren, Z. J.


    Excess planetary CO2 and accompanying ocean acidification are naturally mitigated on geologic time scales via mineral weathering. Here, CO2 acidifies the hydrosphere, which then slowly reacts with silicate and carbonate minerals to produce dissolved bicarbonates that are ultimately delivered to the ocean. This alkalinity not only provides long-term sequestration of the excess atmospheric carbon, but it also chemically counters the effects of ocean acidification by stabilizing or raising pH and carbonate saturation state, thus helping rebalance ocean chemistry and preserving marine ecosystems. Recent research has demonstrated ways of greatly accelerating this process by its integration into energy systems. Specifically, it has been shown (1) that some 80% of the CO2 in a waste gas stream can be spontaneously converted to stable, seawater mineral bicarbonate in the presence of a common carbonate mineral - limestone. This can allow removal of CO2 from biomass combustion and bio-energy production while generating beneficial ocean alkalinity, providing a potentially cheaper and more environmentally friendly negative-CO2-emissions alternative to BECCS. It has also been demonstrated that strong acids anodically produced in a standard saline water electrolysis cell in the formation of H2 can be reacted with carbonate or silicate minerals to generate strong base solutions. These solutions are highly absorptive of air CO2, converting it to mineral bicarbonate in solution. When such electrochemical cells are powered by non-fossil energy (e.g. electricity from wind, solar, tidal, biomass, geothermal, etc. energy sources), the system generates H2 that is strongly CO2-emissions-negative, while producing beneficial marine alkalinity (2-4). The preceding systems therefore point the way toward renewable energy production that, when tightly coupled to geochemical mitigation of CO2 and formation of natural ocean "antacids", forms a high capacity, negative-CO2-emissions, "supergreen

  5. Estimating the costs of reducing CO2 emission via avoided deforestation with integrated assessment modelling

    NARCIS (Netherlands)

    Overmars, K.P.; Tabeau, A.A.; Stehfest, E.; Meijl, van J.C.M.


    Estimates for deforestation and forest degradation were shown to account for about 17% of greenhouse gas emissions. The implementation of REDD is suggested to provide substantial emission reductions at low costs. Proper calculation of such a costs requires integrated modeling approach involving

  6. Integrated underground gas storage of CO2 and CH4 to decarbonize the "power-to-gas-to-gas-to-power" technology (United States)

    Kühn, Michael; Streibel, Martin; Nakaten, Natalie; Kempka, Thomas


    Massive roll-out of renewable energy production units (wind turbines and solar panels) leads to date to excess energy which cannot be consumed at the time of production. So far, long-term storage is proposed via the so called 'power-to-gas' technology. Energy is transferred to methane gas and subsequently combusted for power production - 'power-to-gas-to-power' (PGP) - when needed. PGP profits from the existing infrastructure of the gas market and could be deployed immediately. However, major shortcoming is the production of carbon dioxide (CO2) from renewables and its emission into the atmosphere. We present an innovative idea which is a decarbonised extension of the PGP technology. The concept is based on a closed carbon cycle: (1) Hydrogen (H2) is generated from renewable energy by electrolysis and (2) transformed into methane (CH4) with CO2 taken from an underground geological storage. (3) CH4 produced is stored in a second storage underground until needed and (4) combusted in a combined-cycled power plant on site. (5) CO2 is separated during energy production and re-injected into the storage formation. We studied a show case for the cities Potsdam and Brandenburg/Havel in the Federal State of Brandenburg in Germany to determine the energy demand of the entire process chain and the costs of electricity (COE) using an integrated techno-economic modelling approach (Nakaten et al. 2014). Taking all of the individual process steps into account, the calculation shows an overall efficiency of 27.7 % (Streibel et al. 2013) with total COE of 20.43 euro-cents/kWh (Kühn et al. 2013). Although the level of efficiency is lower than for pump and compressed air storage, the resulting costs are similar in magnitude, and thus competitive on the energy storage market. The great advantage of the concept proposed here is that, in contrast to previous PGP approaches, this process is climate-neutral due to CO2 utilisation. For that purpose, process CO2 is temporally stored in an

  7. A biophysical approach using water deficit factor for daily estimations of evapotranspiration and CO2 uptake in Mediterranean environments (United States)

    Helman, David; Lensky, Itamar M.; Osem, Yagil; Rohatyn, Shani; Rotenberg, Eyal; Yakir, Dan


    Estimations of ecosystem-level evapotranspiration (ET) and CO2 uptake in water-limited environments are scarce and scaling up ground-level measurements is not straightforward. A biophysical approach using remote sensing (RS) and meteorological data (RS-Met) is adjusted to extreme high-energy water-limited Mediterranean ecosystems that suffer from continuous stress conditions to provide daily estimations of ET and CO2 uptake (measured as gross primary production, GPP) at a spatial resolution of 250 m. The RS-Met was adjusted using a seasonal water deficit factor (fWD) based on daily rainfall, temperature and radiation data. We validated our adjusted RS-Met with eddy covariance flux measurements using a newly developed mobile lab system and the single active FLUXNET station operating in this region (Yatir pine forest station) at a total of seven forest and non-forest sites across a climatic transect in Israel (280-770 mm yr-1). RS-Met was also compared to the satellite-borne MODIS-based ET and GPP products (MOD16 and MOD17, respectively) at these sites.Results show that the inclusion of the fWD significantly improved the model, with R = 0.64-0.91 for the ET-adjusted model (compared to 0.05-0.80 for the unadjusted model) and R = 0.72-0.92 for the adjusted GPP model (compared to R = 0.56-0.90 of the non-adjusted model). The RS-Met (with the fWD) successfully tracked observed changes in ET and GPP between dry and wet seasons across the sites. ET and GPP estimates from the adjusted RS-Met also agreed well with eddy covariance estimates on an annual timescale at the FLUXNET station of Yatir (266 ± 61 vs. 257 ± 58 mm yr-1 and 765 ± 112 vs. 748 ± 124 gC m-2 yr-1 for ET and GPP, respectively). Comparison with MODIS products showed consistently lower estimates from the MODIS-based models, particularly at the forest sites. Using the adjusted RS-Met, we show that afforestation significantly increased the water use efficiency (the ratio of carbon uptake to ET) in this region

  8. Comparison of chamber and eddy covariance-based CO2 and CH4 emission estimates in a heterogeneous grass ecosystem on peat

    NARCIS (Netherlands)

    Schrier-Uijl, A.P.; Kroon, P.S.; Hensen, A.; Leffelaar, P.A.; Berendse, F.; Veenendaal, E.M.


    Fluxes of methane (CH4) and carbon dioxide (CO2) estimated by empirical models based on small-scale chamber measurements were compared to large-scale eddy covariance (EC) measurements for CH4 and to a combination of EC measurements and EC-based models for CO2. The experimental area was a flat peat

  9. Phase equilibrium for surfactant Ls-54 in liquid CO(2) with water and solubility estimation using the Peng-Robinson equation of state. (United States)

    Tarafa, Pedro J; Matthews, Michael A


    It is known that the commercial surfactant Dehypon® Ls-54 is soluble in supercritical CO(2) and that it enables formation of water-in-CO(2) microemulsions. In this work we observed phase equilibrium for the Ls-54/CO(2) and Ls-54/water/CO(2) systems in the liquid CO(2) region, from 278.15 - 298.15 K. In addition, the Peng-Robinson equation of state (PREOS) was used to model the phase behavior of Ls-54/CO(2) binary system as well as to estimate water solubilities in CO(2). Ls-54 in CO(2) can have solubilities as high as 0.086 M at 278.15 K and 15.2 MPa. The stability of the microemulsion decreases with increasing concentration of water, and lower temperatures favor increased solubility of water into the one-phase microemulsion. The PREOS model showed satisfactory agreement with the experimental data for both Ls-54/CO(2) and water/CO(2) systems.

  10. Kalundborg case study, a feasibility study of CO{sub 2} storage in onshore saline aquifers. CO2STORE[Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Michael; Bech, N.; Bidstrup, T.; Christensen, Niels Peter; Vangkilde-Pedersen, T. [GEUS (Denmark); Biede, O. [ENERGI E2 (Denmark)


    The Danish case-study of the CO2STORE project comprises the potential future capture and underground storage of CO{sub 2} from two point sources. These are the coal fired power plant Asnaesvaerket and the Statoil refinery both located in the city of Kalundborg, Denmark. Initial mapping of the storage structure was conducted as part of the EU funded research project GESTCO that was concluded in 2003. The study identified a large underground structure forming a potential, future storage site 15 km to the northeast of the city. Porous sandstones filled with saline water at a depth of approximately 1.500 m form the reservoir. The structure covers approximately 160 km{sup 2} and a preliminary calculation suggests a storage capacity of nearly 900 million tonnes of CO2 equal to more than 150 years of CO{sub 2} emissions from the two point sources. In the Kalundborg case-study, a fictive capture and storage scenario will be formulated and modelled. The scenario is based on experiences learned through the SACS and GESTCO projects. Detailed geological modelling, reservoir simulation, reservoir and cap rock characterisation and risk assessment will be important issues for the case-study. The Geological Survey of Denmark and Greenland (GEUS) is project leader for the Kalundborg case-study. Information on CO{sub 2} emissions from the point sources and technical and economical input for the three scenarios is provided by the industrial partners; ENERGI E2 and Statoil ASA. The scenario is designed only for this case study and does not reflect the strategic plans of ENERGI E2 nor Statoil ASA. Geochemical simulation and modelling studies on reservoir and cap rock were performed at Bureau de Recherches Geologiques et Minieres (BRGM) in France. The CO2STORE project is performed within the European Community supported 5th Framework Programme. (au)

  11. Low temperature and short-term high-CO2 treatment in postharvest storage of table grapes at two maturity stages: Effects on transcriptome profiling.

    Directory of Open Access Journals (Sweden)

    Raquel Rosales


    Full Text Available Table grapes (Vitis vinifera cv. Cardinal are highly perishable and their quality deteriorates during postharvest storage at low temperature mainly because of sensitivity to fungal decay and senescence of rachis. The application of a 3-day CO2 treatment (20 kPa CO2 + 20 kPa O2 + 60 kPa N2 at 0ºC reduced total decay and retained fruit quality in early and late-harvested table grapes during postharvest storage. In order to study the transcriptional responsiveness of table grapes to low temperature and high CO2 levels in the first stage of storage and how the maturity stage affect these changes, we have performed a comparative large-scale transcriptional analysis using the custom-made GrapeGen GeneChip®. In the first stage of storage, low temperature led to a significantly intense change in grape skin transcriptome irrespective of fruit maturity, although there were different changes within each stage. In the case of CO2 treated samples, in comparison to fruit at time zero, only slight differences were observed. Functional enrichment analysis revealed that major modifications in the transcriptome profile of early- and late-harvested grapes stored at 0ºC are linked to biotic and abiotic stress-responsive terms. However, in both cases there is a specific reprogramming of the transcriptome during the first stage of storage at 0ºC in order to withstand the cold stress. Thus, genes involved in gluconeogenesis, photosynthesis, mRNA translation and lipid transport were up-regulated in the case of early-harvested grapes, and genes related to protein folding stability and intracellular membrane trafficking in late-harvested grapes. The beneficial effect of high CO2 treatment maintaining table grape quality seems to be an active process requiring the induction of several transcription factors and kinases in early-harvested grapes, and the activation of processes associated to the maintenance of energy in late-harvested grapes.

  12. Micro-scale thermal imaging of CO2 absorption in the thermochemical energy storage of Li metal oxides at high temperature (United States)

    Morikawa, Junko; Takasu, Hiroki; Zamengo, Massimiliano; Kato, Yukitaka


    Li-Metal oxides (typical example: lithium ortho-silicate Li4SiO4) are regarded as a novel solid carbon dioxide CO2 absorbent accompanied by an exothermic reaction. At temperatures above 700°C the sorbent is regenerated with the release of the captured CO2 in an endothermic reaction. As the reaction equilibrium of this reversible chemical reaction is controllable only by the partial pressure of CO2, the system is regarded as a potential candidate for chemical heat storage at high temperatures. In this study, we applied our recent developed mobile type instrumentation of micro-scale infrared thermal imaging system to observe the heat of chemical reaction of Li4SiO4 and CO2 at temperature higher than 600°C or higher. In order to quantify the micro-scale heat transfer and heat exchange in the chemical reaction, the superimpose signal processing system is setup to determine the precise temperature. Under an ambient flow of carbon dioxide, a powder of Li4SiO4 with a diameter 50 micron started to shine caused by an exothermic chemical reaction heat above 600°C. The phenomena was accelerated with increasing temperature up to 700°C. At the same time, the reaction product lithium carbonate (Li2CO3) started to melt with endothermic phase change above 700°C, and these thermal behaviors were captured by the method of thermal imaging. The direct measurement of multiple thermal phenomena at high temperatures is significant to promote an efficient design of chemical heat storage materials. This is the first observation of the exothermic heat of the reaction of Li4SiO4 and CO2 at around 700°C by the thermal imaging method.

  13. A novel condensation reactor for efficient CO2 to methanol conversion for storage of renewable electric energy

    NARCIS (Netherlands)

    Bos, Martin Johan; Brilman, Derk Willem Frederik


    A novel reactor design for the conversion of CO2 and H2 to methanol is developed. The conversion limitations because of thermodynamic equilibrium are bypassed via in situ condensation of a water/methanol mixture. Two temperatures zones inside the reactor ensure optimal catalyst activity (high

  14. Geomechanical modeling of surface uplift around well KB-502 at the in Salah CO2 storage site

    NARCIS (Netherlands)

    Fokker, P.A.; Orlic, B.; Meer, L.G.H. van der; Geel, C.R.


    Injection of CO2 in the InSalah field has caused uplift of the surface, as observed by satellite geodetic techniques (InSAR). Around one of the wells, KB-502, the uplift shows anomalous behaviour: a two-lobe pattern develops in the direction of the preferred fracture orientation. This indicates the

  15. High CO2 levels in the Proterozoic atmosphere estimated from analyses of individual microfossils. (United States)

    Kaufman, Alan J; Xiao, Shuhai


    Solar luminosity on the early Earth was significantly lower than today. Therefore, solar luminosity models suggest that, in the atmosphere of the early Earth, the concentration of greenhouse gases such as carbon dioxide and methane must have been much higher. However, empirical estimates of Proterozoic levels of atmospheric carbon dioxide concentrations have not hitherto been available. Here we present ion microprobe analyses of the carbon isotopes in individual organic-walled microfossils extracted from a Proterozoic ( approximately 1.4-gigayear-old) shale in North China. Calculated magnitudes of the carbon isotope fractionation in these large, morphologically complex microfossils suggest elevated levels of carbon dioxide in the ancient atmosphere--between 10 and 200 times the present atmospheric level. Our results indicate that carbon dioxide was an important greenhouse gas during periods of lower solar luminosity, probably dominating over methane after the atmosphere and hydrosphere became pervasively oxygenated between 2 and 2.2 gigayears ago.

  16. Zn(II, Mn(II and Sr(II Behavior in a Natural Carbonate Reservoir System. Part II: Impact of Geological CO2 Storage Conditions

    Directory of Open Access Journals (Sweden)

    Auffray B.


    Full Text Available Some key points still prevent the full development of geological carbon sequestration in underground formations, especially concerning the assessment of the integrity of such storage. Indeed, the consequences of gas injection on chemistry and petrophysical properties are still much discussed in the scientific community, and are still not well known at either laboratory or field scale. In this article, the results of an experimental study about the mobilization of Trace Elements (TE during CO2 injection in a reservoir are presented. The experimental conditions range from typical storage formation conditions (90 bar, supercritical CO2 to shallower conditions (60 and 30 bar, CO2 as gas phase, and consider the dissolution of the two carbonates, coupled with the sorption of an initial concentration of 10−5 M of Zn(II, and the consequent release in solution of Mn(II and Sr(II. The investigation goes beyond the sole behavior of TE in the storage conditions: it presents the specific behavior of each element with respect to the pressure and the natural carbonate considered, showing that different equilibrium concentrations are to be expected if a fluid with a given concentration of TE leaks to an upper formation. Even though sorption is evidenced, it does not balance the amount of TE released by the dissolution process. The increase in porosity is clearly evidenced as a linear function of the CO2 pressure imposed for the St-Emilion carbonate. For the Lavoux carbonate, this trend is not confirmed by the 90 bar experiment. A preferential dissolution of the bigger family of pores from the preexisting porosity is observed in one of the samples (Lavoux carbonate while the second one (St-Emilion carbonate presents a newly-formed family of pores. Both reacted samples evidence that the pore network evolves toward a tubular network type.

  17. The Cross-Calibration of Spectral Radiances and Cross-Validation of CO2 Estimates from GOSAT and OCO-2

    Directory of Open Access Journals (Sweden)

    Fumie Kataoka


    Full Text Available The Greenhouse gases Observing SATellite (GOSAT launched in January 2009 has provided radiance spectra with a Fourier Transform Spectrometer for more than eight years. The Orbiting Carbon Observatory 2 (OCO-2 launched in July 2014, collects radiance spectra using an imaging grating spectrometer. Both sensors observe sunlight reflected from Earth’s surface and retrieve atmospheric carbon dioxide (CO2 concentrations, but use different spectrometer technologies, observing geometries, and ground track repeat cycles. To demonstrate the effectiveness of satellite remote sensing for CO2 monitoring, the GOSAT and OCO-2 teams have worked together pre- and post-launch to cross-calibrate the instruments and cross-validate their retrieval algorithms and products. In this work, we first compare observed radiance spectra within three narrow bands centered at 0.76, 1.60 and 2.06 µm, at temporally coincident and spatially collocated points from September 2014 to March 2017. We reconciled the differences in observation footprints size, viewing geometry and associated differences in surface bidirectional reflectance distribution function (BRDF. We conclude that the spectral radiances measured by the two instruments agree within 5% for all bands. Second, we estimated mean bias and standard deviation of column-averaged CO2 dry air mole fraction (XCO2 retrieved from GOSAT and OCO-2 from September 2014 to May 2016. GOSAT retrievals used Build 7.3 (V7.3 of the Atmospheric CO2 Observations from Space (ACOS algorithm while OCO-2 retrievals used Version 7 of the OCO-2 retrieval algorithm. The mean biases and standard deviations are −0.57 ± 3.33 ppm over land with high gain, −0.17 ± 1.48 ppm over ocean with high gain and −0.19 ± 2.79 ppm over land with medium gain. Finally, our study is complemented with an analysis of error sources: retrieved surface pressure (Psurf, aerosol optical depth (AOD, BRDF and surface albedo inhomogeneity. We found no change in XCO2

  18. Petrophysical laboratory invertigations of carbon dioxide storage in a subsurface saline aquifer in Ketzin/Germany within the scope of CO2SINK (United States)

    Zemke, K.; Kummmerow, J.; Wandrey, M.; Co2SINK Group


    Since June of 2008 carbon dioxide has been injected into a saline aquifer at the Ketzin test site [Würdemann et al., this volume]. The food grade CO2 is injected into a sandstone zone of the Stuttgart formation at ca. 650 m depth at 35°C reservoir temperature and 62 bar reservoir pressure. With the injection of CO2 into the geological formation, chemical and physical reservoir characteristics are changed depending on pressure, temperature, fluid chemistry and rock composition. Fluid-rock interaction could comprise dissolution of non-resistant minerals in CO2-bearing pore fluids, cementing of the pore space by precipitating substances from the pore fluid, drying and disintegration of clay minerals and thus influence of the composition and activities of the deep biosphere. To testing the injection behaviour of CO2 in water saturated rock and to evaluate the geophysical signature depending on the thermodynamic conditions, flow experiments with water and CO2 have been performed on cores of the Stuttgart formation from different locations including new wells of ketzin test site. The studied core material is an unconsolidated fine-grained sandstone with porosity values from 15 to 32 %. Permeability, electrical resistivity, and sonic wave velocities and their changes with pressure, saturation and time have been studied under simulated in situ conditions. The flow experiments conducted over several weeks with brine and CO2 showed no significant changes of resistivity and velocity and a slightly decreasing permeability. Pore fluid analysis showed mobilization of clay and some other components. A main objective of the CO2Sink laboratory program is the assessment of the effect of long-term CO2 exposure on reservoir rocks to predict the long-term behaviour of geological CO2 storage. For this CO2 exposure experiments reservoir rock samples were exposed to CO2 saturated reservoir fluid in corrosion-resistant high pressure vessels under in situ temperature and pressure

  19. Potential environmental issues of CO2 storage in deep saline aquifers: Geochemical results from the Frio-I Brine Pilot test, Texas, USA (United States)

    Kharaka, Yousif K.; Thordsen, James J.; Hovorka, Susan D.; Nance, H. Seay; Cole, David R.; Phelps, Tommy J.; Knauss, Kevin G.


    Sedimentary basins in general, and deep saline aquifers in particular, are being investigated as possible repositories for large volumes of anthropogenic CO2 that must be sequestered to mitigate global warming and related climate changes. To investigate the potential for the long-term storage of CO2 in such aquifers, 1600 t of CO2 were injected at 1500 m depth into a 24-m-thick "C" sandstone unit of the Frio Formation, a regional aquifer in the US Gulf Coast. Fluid samples obtained before CO2 injection from the injection well and an observation well 30 m updip showed a Na–Ca–Cl type brine with ∼93,000 mg/L TDS at saturation with CH4 at reservoir conditions; gas analyses showed that CH4 comprised ∼95% of dissolved gas, but CO2 was low at 0.3%. Following CO2 breakthrough, 51 h after injection, samples showed sharp drops in pH (6.5–5.7), pronounced increases in alkalinity (100–3000 mg/L as HCO3) and in Fe (30–1100 mg/L), a slug of very high DOC values, and significant shifts in the isotopic compositions of H2O, DIC, and CH4. These data, coupled with geochemical modeling, indicate corrosion of pipe and well casing as well as rapid dissolution of minerals, especially calcite and iron oxyhydroxides, both caused by lowered pH (initially ∼3.0 at subsurface conditions) of the brine in contact with supercritical CO2.These geochemical parameters, together with perfluorocarbon tracer gases (PFTs), were used to monitor migration of the injected CO2 into the overlying Frio “B”, composed of a 4-m-thick sandstone and separated from the “C” by ∼15 m of shale and siltstone beds. Results obtained from the Frio “B” 6 months after injection gave chemical and isotopic markers that show significant CO2 (2.9% compared with 0.3% CO2 in dissolved gas) migration into the “B” sandstone. Results of samples collected 15 months after injection, however, are ambiguous, and can be interpreted to show no additional injected CO2 in the “B” sandstone


    Energy Technology Data Exchange (ETDEWEB)

    Michael J. Mudd; Howard Johnson; Charles Christopher; T.S. Ramakrishnan, Ph.D.


    ,100 ft above the basal sandstone and is 100-200 ft thick. The storage capacity estimates for a 20-mile radius from the injection well ranged from 39-78 million tons (Mt) for each formation. Several other oil and gas plays have hydraulic properties conducive for injection, but the formations are generally only 5-50 ft thick in the study area. Overlying the injection reservoirs are thick sequences of dense, impermeable dolomite, limestone, and shale. These layers provide containment above the potential injection reservoirs. In general, it appears that the containment layers are much thicker and extensive than the injection intervals. Other physical parameters for the study area appear to be typical for the region. Anticipated pressures at maximum depths are approximately 4,100 psi based on a 0.45 psi/ft pressure gradient. Temperatures are likely to be 150 F. Groundwater flow is slow and complex in deep formations. Regional flow directions appear to be toward the west-northwest at less than 1 ft per year within the basal sandstone. Vertical gradients are downward in the study area. A review of brine geochemistry indicates that formation fluids have high salinity and dissolved solids. Total dissolved solids ranges from 200,000-325,000 mg/L in the deep reservoirs. Brine chemistry is similar throughout the different formations, suggesting extensive mixing in a mature basin. Unconsolidated sediments in the Ohio River Valley are the primary source of drinking water in the study area.

  1. Variations in Belowground Carbon Storage and Soil CO2 Flux Rates along a Wet Tropical Climate Gradient (United States)

    Megan McGroddy; Whendee L. Silver


    We used a humid tropical elevation gradient to examine the relationships among climate, edaphic conditions, belowground carbon storage, and soil respiration rates. We also compared open and closed canopy sites to increase the range of microclimate conditions sampled along the gradient, and determine the effects of canopy openings on C and P storage, and C dynamics....

  2. Experimental and modeling results on geochemical impacts of leaking CO2 from subsurface storage reservoirs to an unconfined oxidizing carbonate aquifer (United States)

    Qafoku, N. P.; Bacon, D. H.; Shao, H.; Lawter, A.; Wang, G.; Brown, C. F.


    Deep subsurface storage and sequestration of CO2 has been identified as a potential mitigation technique for rising atmospheric CO2 concentrations. Sequestered CO2 represents a potential risk to overlying aquifers if the CO2 leaks from the deep storage reservoir. Experimental and modeling work is required to evaluate risks to groundwater quality and develop a systematic understanding on how CO2 leakage may cause important changes in aquifer chemistry and mineralogy by promoting dissolution/precipitation, adsorption/desorption, and redox reactions. Solid materials (rocks and slightly weathered rocks) from an unconfined aquifer, i.e., the Edwards Aquifer in Texas, were used in this investigation. The experimental part consisted of: 1) wet chemical acid extractions (8M HNO3 solution at 90 0C); 2) batch experiments conducted at low solid to solution ratios to study time-dependent releases of major, minor and trace elements during periodic or continuous exposure to CO2 gas; 3) hydraulically saturated column experiments conducted under continuous and stop-flow conditions using a CO2 gas saturated synthetic groundwater; 4) pre- and post-treatment solid phase characterization studies. Major variables tested included reaction time (0-336 hours), CO2 flow rate (50 to 350 ml/min), brine concentration (0.1 and 1 M NaCl), rock type and particle size fraction. We are currently investigating the solution composition effects (i.e., presence of contaminants in the initial solution) on the fate and behavior of potential contaminants (As, Pb and Cd) in these systems. Results from the solid phase characterization studies showed that the mineralogy of the Edwards aquifer materials was dominated by calcite. Quartz and montmorillonite were also present in some samples. Acid extractions confirmed that the solid phase had appreciable amounts of potential contaminants (As, Cd, Cr, Cu, Pb and Zn). However, the results from the batch and column experiments demonstrated that these contaminants

  3. The effects of CO2 injection on Geochemistry and Aquifer properties investigated at a hypothetical storage site in the north German basin (United States)

    Graupner, B. J.; Li, D.; Benisch, K.; Mitiku, A. B.; Beyer, C.; Bauer, S.


    The storage of CO2 in deep saline aquifers is one of the major options for carbon dioxide sequestration. With the injection of CO2 in the underground a CO2 phase will migrate through the target reservoir controlled by the pressure gradient and buoyancy. Over the time CO2 dissolves in water and stimulates geochemical reactions like mineral dissolution due to the acidic conditions that might be followed by mineral precipitation again. Mineral dissolution and precipitation affects the porosity and permeability and thus feeds back on multiphase flow. To evaluate the behaviour of the storage system the coupled simulator OGS-Eclipse-ChemApp was developed, which provides the coupled multiphase flow and reactive transport simulation under conditions typical for CO2 injection. The open-source scientific software OpenGeoSys (OGS) was used in this investigation to simulate CO2 injection into a saline formation. To represent the hydraulic and geochemical alteration during CO2 sequestration under reservoir conditions, OGS was coupled to the widely used multiphase flow simulator ECLIPSE for modelling multiphase flow. Geochemical reactions are considered with an already existing interface between OGS and PhreeqC. Furthermore changes in porosity and permeability were considered. ECLIPSE and OGS are coupled using an operator splitting approach. Results of the multiphase flow simulation are passed for each time step from ECLIPSE to OGS where transport of dissolved species is calculated. Transport of components can be considered with OGS in the CO2 as well as in the water phase. Transport in the water phase is of major interest for reactive transport simulations. Subsequently, equilibrium geochemical reactions at each node of the OGS FEM model grid can be calculated using ChemApp. Changes in the brine concentration of dissolved inorganic carbon due to chemical reactions are transferred back to the multiphase flow simulator, which calculates the new phase equilibrium in the next time

  4. Evaluating the Sealing Effectiveness of a Caprock-Fault System for CO2-EOR Storage: A Case Study of the Shengli Oilfield

    Directory of Open Access Journals (Sweden)

    Bing Bai


    Full Text Available An effective sealing system is crucial for CO2-EOR storage, and these sealing systems are typically composed of the caprocks and faults that surround a reservoir. Therefore, the sealing effectiveness of a caprock-fault system must be evaluated at various stages of CO2-EOR storage projects. This paper presents a new evaluation framework that considers specific site characteristics and a case study on the sealing effectiveness of the caprock-fault system in the Shengli Oilfield. The proposed method is a weighted ranking system where a set of 17 indicators has been developed for the assessment and ranking of the G89 block in terms of their sealing ability for CO2 sequestration. Additional indicators are involved in the method, such as the newly proposed parameter, frontier displacement work which reflects the influence of formation pressure, displacement pressure resistance, and caprock thickness. The new approach considers the sealing mechanisms of caprocks and faults as well as the configuration relationships between them. The method was used to evaluate the sealing effectiveness of the G89 block that has a considerable number of faults and good sealing ability of caprock in the Shengli Oilfield.

  5. Simultaneous studies on solar energy storage by CO2 reduction to HCOOH with Brilliant Green dye removal photoelectrochemically

    Directory of Open Access Journals (Sweden)

    V.S.K. Yadav


    Full Text Available The simultaneous study on photoelectrochemical CO2 reduction with Brilliant Green (BG dye removal was studied in the present work. Experimental studies were done in aqueous solutions of sodium and potassium based electrolytes using a cathode [Zinc (Zn and Tin (Sn] and a common cobalt oxide (Co3O4 anode electrocatalyst. The influence of reaction with electrolyte concentration for the both catalysts was shown clearly with respect to time. The selected electrocatalysts were able to reduce CO2 to formic acid (HCOOH along with high BG dye removal. With Sn as cathode, the maximum BG dye removal was obtained to be KHCO3–[95.9% (10 min–0.2 M], NaHCO3–[98.6% (15 min–0.6 M]. Similarly for Zn, KHCO3–[99.8% (10 min–0.4 M], NaHCO3–[99.9% (20 min–0.8 M] were observed respectively. Finally, the results have proven that higher efficiencies for BG dye removal were obtained along with HCOOH formation, which might be a better alternate for water purification and to decrease the atmospheric CO2 concentrations.

  6. Testing a new Method of Estimating the δ13C of Photosynthate in Trees: Stem CO2 Equilibration} (United States)

    Ubierna Lopez, N.; Kavanagh, K.; Marshall, J. D.


    Modeling and prediction of forest responses to climate change often deal with the difficulty of estimating gas- exchange responses to rising CO2 concentrations and temperatures. This difficulty can be overcome with stable carbon isotopes, which provide a tool to study the coupling of the carbon and water cycles. Recently, considerable research has concentrated on trying to identify processes occurring after photosynthesis that modify the isotopic composition of a given plant tissue, which has led to questions about which plant tissue will best reflect environmental variations and photosynthetic discrimination. Here, we propose a new method that uses CO2 collected from inside the stem. A simple collection apparatus consisting of a stainless steel tube is inserted into the tree. The gas from the stem diffuses and equilibrates with the headspace. Gas samples are subsequently collected by replacing the gas inside the tubing with acidified water. This technique minimizes any change in pressure inside the system or any atmospheric contamination from outside the system. We compared the measured δ13C of stem CO2 to known leaf values in four conifer species at Mica Creek Experimental Watershed, in northern Idaho, USA. In addition, δ13C of soil respiration, δ13C leaf bulk material, δ13C phloem contents, and photosynthetic gas- exchange data were collected. We collected stem CO2 samples weekly through August 2006 during a long drought period. Mean monthly temperature was 16°C, cumulative precipitation in July and August was 33 mm, and mean maximum VPD was 4.1 kPa during this month. The most depleted species was Larix occidentalis, with δ13C = -26.97 ‰ (SE = 0.30), following by the shade-tolerant Abies grandis, with δ13C = -26.33 ‰ (SE = 0.23). In comparison, Pseudotsuga menziesii, with δ13C = -24.88 ‰ (SE =0.48) and Thuja plicata with δ13C = - 23.79 ‰ (SE = 0.30) were more enriched. These δ13C values are consistent with previous measurements of leaf bulk

  7. Carbon dioxide emissions from lakes and reservoirs of China: A regional estimate based on the calculated pCO2 (United States)

    Wen, Zhidan; Song, Kaishan; Shang, Yingxin; Fang, Chong; Li, Lin; Lv, Lili; Lv, Xianguo; Chen, Lijiang


    The role of inland water in CO2 exchange with the atmosphere was evaluated on the basis of calculated partial pressure of CO2 (pCO2) from sampling of 207 lakes and 84 reservoirs across China in late summer. The results suggested that almost 60% of these water bodies were supersaturated with CO2 with respect to atmosphere, and the collected reservoirs samples exhibited higher mean pCO2 than lakes. The mean pCO2 in fresh water lakes was about 3.5 times of the value in saline lakes. The lakes and reservoirs were divided into five groups (Inner Mongolia -Xinjiang plateau region, Tibetan Plateau region, Northeastern plain and mountainous region, Yunnan- Guizhou Plateau region, and Eastern plain region). The Yunnan- Guizhou Plateau region showed the highest pCO2 compared with other regions, most likely due to the typical karst landforms, karst processes may promote aqueous CO2 concentration, and karstification has a significant effect on the capture of atmospheric CO2. Inner Mongolia-Xinjiang plateau and Tibetan Plateau region reserviors showed negative CO2 flux to atmosphere, other waters in this study all supersaturated with CO2 with respect to the atmosphere. A which We analyzed the relationship between pCO2 and environmental variables, and results showed that some indicators had correlations with pCO2 in individual region such as total phosphorus, dissolved organic matter, and total suspended solids, but the relationship could not be observed with all surveyed waters. This indicated that it might be much more effective in a smaller regional scale than the broadened scale when the environmental factors were used as the predictor of pCO2 in lakes. Therefore, the common algorithm that extrapolates CO2 concentration or emission flux from the study region to a wider scale might not be accurate because of the changes in the environmental and water quality conditions.

  8. Spatial Estimation and Visualization of CO2 Emissions for Campus Sustainability: The Case of King Abdullah University of Science and Technology (KAUST, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Yusuf A. Adenle


    Full Text Available A total of 21 metric tons of CO2 per person in terms of per capita emissions from consumption of energy was recorded in Saudi Arabia in 2011 and forecasts have shown that this emission of CO2 is increasing. This poses the threat of climate change and global warming and therefore the need for the sustainability of the country. The Kingdom of Saudi Arabia’s Vision for 2030 addresses environmental sustainability that includes a reduction in CO2 emissions as well as diversified economic growth. Universities have been regarded as institutions with significant responsibilities to resolve the issues of sustainability as well as serve as role model to society by implementing a sustainability plan. This study established a spatial evaluation, estimation, and visualization of the CO2 emissions of King Abdullah University of Science and Technology (KAUST, Saudi Arabia. The data required for this study were collected from the overall coverage of the university campus buildings by transforming raster data from the satellite image to vector data in the form of polygons, and then multiplying the area by the number of floors of the individual building. ArcGIS 10.3® (ESRI, Redlands, CA, USA software was used for this campus CO2 emissions evaluation and visualization. The overall estimate of the CO2 emissions for the university campus was 127.7-tons CO2 equivalent. The lowest emission was 0.02-tons CO2 equivalent while the maximum value was 20.9-tons of CO2 equivalent. By this ArcGIS-based evaluation, it is evident that geographically integrated model for campus estimation and visualization of CO2 emissions provides the information for decision makers to develop viable strategies for achieving a higher standard in overall campus sustainability and addressing the issue of climate change.

  9. Comparison of Pore-Network and Lattice Boltzmann Models for Pore-Scale Modeling of Geological Storage of CO2 in Natural Reservoir Rocks (United States)

    Kohanpur, A. H.; Chen, Y.; Valocchi, A. J.; Tudek, J.; Crandall, D.


    CO2-brine flow in deep natural rocks is the focus of attention in geological storage of CO2. Understanding rock/flow properties at pore-scale is a vital component in field-scale modeling and prediction of fate of injected CO2. There are many challenges in working at the pore scale, such as size and selection of representative elementary volume (REV), particularly for material with complex geometry and heterogeneity, and the high computational costs. These issues factor into trade-offs that need to be made in choosing and applying pore-scale models. On one hand, pore-network modeling (PNM) simplifies the geometry and flow equations but can provide characteristic curves on fairly large samples. On the other hand, the lattice Boltzmann method (LBM) solves Navier-Stokes equations on the real geometry but is limited to small samples due to its high computational costs. Thus, both methods have some advantages but also face some challenges, which warrants a more detailed comparison and evaluation. In this study, we used industrial and micro-CT scans of actual reservoir rock samples to characterize pore structure at different resolutions. We ran LBM models directly on the characterized geometry and PNM on the equivalent 3D extracted network to determine single/two-phase flow properties during drainage and imbibition processes. Specifically, connectivity, absolute permeability, relative permeability curve, capillary pressure curve, and interface location are compared between models. We also did simulations on several subsamples from different locations including different domain sizes and orientations to encompass analysis of heterogeneity and isotropy. This work is primarily supported as part of the Center for Geologic Storage of CO2, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science and partially supported by the International Institute for Carbon-Neutral Energy Research (WPI-I2CNER) based at Kyushu University, Japan.

  10. Strategic use of the underground for an energy mix plan, synergies among CO2 and CH4 Geological Storage and Geothermal Energy: Italian Energy review and Latium case study (United States)

    Procesi, M.; Cantucci, B.; Buttinelli, M.; Armezzani, G.; Quattrocchi, F.


    new energy plan to improve the efficiency and the environmental sustainability is necessary. The evaluations of potential areas suitable for CO2 and/or CH4 geological storage and geothermal energy in the Latium region, have been done through a revisiting of public data such as well composite logs and maps. For the selection has been taken in account too, exclusion criteria sites as well as presence of geological risks and natural protected areas. Then the storage capacity and geothermal potentiality have been estimated for the selected areas. Finally, considering the hypothesized energy mix plan, an evaluation of the potential CO2 emissions decrease has been done. Preliminary results are encouraging to extent this evaluation also in other regions to improve a National Energy Plan.

  11. Management of uncertainties on parameters elicited by experts - Applications to sea-level rise and to CO2 storage operations risk assessment (United States)

    Manceau, Jean-Charles; Loschetter, Annick; Rohmer, Jérémy; Le Cozannet, Gonéri; Lary Louis, de; Guénan Thomas, Le; Ken, Hnottavange-Telleen


    In a context of high degree of uncertainty, when very few data are available, experts are commonly requested to provide their opinions on input parameters of risk assessment models. Not only might each expert express a certain degree of uncertainty on his/her own statements, but the set of information collected from the pool of experts introduces an additional level of uncertainty. It is indeed very unlikely that all experts agree on exactly the same data, especially regarding parameters needed for natural risk assessments. In some cases, their opinions may differ only slightly (e.g. the most plausible value for a parameter is similar for different experts, and they only disagree on the level of uncertainties that taint the said value) while on other cases they may express incompatible opinions for a same parameter. Dealing with these different kinds of uncertainties remains a challenge for assessing geological hazards or/and risks. Extra-probabilistic approaches (such as the Dempster-Shafer theory or the possibility theory) have shown to offer promising solutions for representing parameters on which the knowledge is limited. It is the case for instance when the available information prevents an expert from identifying a unique probability law to picture the total uncertainty. Moreover, such approaches are known to be particularly flexible when it comes to aggregating several and potentially conflicting opinions. We therefore propose to discuss the opportunity of applying these new theories for managing the uncertainties on parameters elicited by experts, by a comparison with the application of more classical probability approaches. The discussion is based on two different examples. The first example deals with the estimation of the injected CO2 plume extent in a reservoir in the context of CO2 geological storage. This estimation requires information on the effective porosity of the reservoir, which has been estimated by 14 different experts. The Dempster

  12. Development of Geostatistical Models to Estimate CO2 Storage Resource in Sedimentary Geologic Formations (United States)

    Popova, Olga H.

    Dental hygiene students must embody effective critical thinking skills in order to provide evidence-based comprehensive patient care. The problem addressed in this study it was not known if and to what extent concept mapping and reflective journaling activities embedded in a curriculum over a 4-week period, impacted the critical thinking skills of 22 first and second-year dental hygiene students attending a community college in the Midwest. The overarching research questions were: what is the effect of concept mapping, and what is the effect of reflective journaling on the level of critical thinking skills of first and second year dental hygiene students? This quantitative study employed a quasi-experimental, pretest-posttest design. Analysis of Covariance (ANCOVA) assessed students' mean scores of critical thinking on the California Critical Thinking Skills Test (CCTST) pretest and posttest for the concept mapping and reflective journaling treatment groups. The results of the study found an increase in CCTST posttest scores with the use of both concept mapping and reflective journaling. However, the increase in scores was not found to be statistically significant. Hence, this study identified concept mapping using Ausubel's assimilation theory and reflective journaling incorporating Johns's revision of Carper's patterns of knowing as potential instructional strategies and theoretical models to enhance undergraduate students' critical thinking skills. More research is required in this area to draw further conclusions. Keywords: Critical thinking, critical thinking development, critical thinking skills, instructional strategies, concept mapping, reflective journaling, dental hygiene, college students.

  13. Coupled Hydro-Mechanical Simulations of CO2 Storage Supported by Pressure Management Demonstrate Synergy Benefits from Simultaneous Formation Fluid Extraction

    Directory of Open Access Journals (Sweden)

    Kempka Thomas


    Full Text Available We assessed the synergetic benefits of simultaneous formation fluid extraction during CO2 injection for reservoir pressure management by coupled hydro-mechanical simulations at the prospective Vedsted storage site located in northern Denmark. Effectiveness of reservoir pressure management was investigated by simulation of CO2 storage without any fluid extraction as well as with 66% and 100% equivalent volume formation fluid extraction from four wells positioned for geothermal heat recovery. Simulation results demonstrate that a total pressure reduction of up to about 1.1 MPa can be achieved at the injection well. Furthermore, the areal pressure perturbation in the storage reservoir can be significantly decreased compared to the simulation scenario without any formation fluid extraction. Following a stress regime analysis, two stress regimes were considered in the coupled hydro-mechanical simulations indicating that the maximum ground surface uplift is about 0.24 m in the absence of any reservoir pressure management. However, a ground uplift mitigation of up to 37.3% (from 0.24 m to 0.15 m can be achieved at the injection well by 100% equivalent volume formation fluid extraction. Well-based adaptation of fluid extraction rates can support achieving zero displacements at the proposed formation fluid extraction wells located close to urban infrastructure. Since shear and tensile failure do not occur under both stress regimes for all investigated scenarios, it is concluded that a safe operation of CO2 injection with simultaneous formation fluid extraction for geothermal heat recovery can be implemented at the Vedsted site.

  14. Pockmark development in the Petrel Sub-basin, Timor Sea, Northern Australia: Seabed habitat mapping in support of CO2 storage assessments (United States)

    Nicholas, W. A.; Nichol, S. L.; Howard, F. J. F.; Picard, K.; Dulfer, H.; Radke, L. C.; Carroll, A. G.; Tran, M.; Siwabessy, P. J. W.


    The extent to which fluids may leak from sedimentary basins to the seabed is a critical issue for assessing the potential of a basin for carbon capture and storage. The Petrel Sub-basin, located beneath central and eastern Joseph Bonaparte Gulf in tropical northern Australia, was identified as potentially suitable for the geological storage of CO2 because of its geological characteristics and proximity to offshore gas and petroleum resources. In May 2012, a multidisciplinary marine survey (SOL5463) was undertaken to collect data in two targeted areas of the Petrel Sub-basin to facilitate an assessment of its CO2 storage potential. This paper focuses on Area 1 of that survey, a 471 km2 area of sediment-starved shelf (water depths of 78 to 102 m), characterised by low-gradient plains, low-lying ridges, palaeo-channels and shallow pockmarks. Three pockmark types are recognised: small shallow unit pockmarks 10-20 m in diameter (generally <1 m, rarely to 2 m deep), composite pockmarks of 150-300 m diameter formed from the co-location of several cross-cutting pockmarks forming a broad shallow depression (<1 m deep), and pockmark clusters comprised of shallow unit pockmarks co-located side by side (150-300 m width overall, <1 m deep). Pockmark distribution is non-random, focused within and adjacent to palaeo-channels, with pockmark clusters also located adjacent to ridges. Pockmark formation is constrained by AMS 14C dating of in situ mangrove deposits and shells to have begun after 15.5 cal ka BP when a rapid marine transgression of Bonaparte Shelf associated with meltwater pulse 1A drowned coastal mangrove environments. Pockmark development is likely an ongoing process driven by fluid seepage at the seabed, and sourced from CO2 produced in the shallow sub-surface (<2 m) sediment. No evidence for direct connection to deeper features was observed.

  15. Spatio-temporal Estimates of CO2 Emissions in the Los Angeles Basin from On-road and Airport Traffic (United States)

    Rao, P.; Song, Y.; Patarasuk, R.; Gurney, K. R.; Eldering, A.; O'Keeffe, D.; Miller, C. E.; Duren, R. M.


    Characterizing the spatio-temporal distribution of fossil fuel CO2 (FFCO2) emissions in urban landscapes is challenging. We use Hestia, an innovative "bottom up" approach for estimating FFCO2 emissions in the Los Angeles (LA) megacity and Southern California Air Basin (SCAB) which account for ~53% of the FFCO2 emissions in California. Hestia-LA, in coordination with "top down" atmospheric CO2 measurements, will provide baseline FFCO2 emissions, help monitor changes in emissions, and develop emissions mitigation policies. Hestia-LA characterizes FFCO2 emissions at the building/street spatial scale (10-100 m) and at hourly time steps in the basin by combining data on residential and commercial building emissions, industrial processes, electricity production, and different transportation sectors. We report here on the construction of the spatial and temporal structure in two key transportation sectors within the SCAB: on-road vehicle (46%) and aircraft (2%) emissions. We quantified on-road traffic emissions by merging traffic data from Southern California Association of Governments, California Freeway Performance Measurement System and modeled motor vehicle emissions from EPA's NMIM model. Preliminary analysis shows that (1) LA and Orange counties dominate the annual FFCO2 emissions from urban freeways and arterials, and (2) LA county has a wider peak traffic period during weekdays (2-6pm) than the other four counties (4-5pm). We characterized airport emissions by integrating information from Federal Aviation Administration, Los Angeles World Airports, and Airnav LLC for the temporal structure of aircraft arrivals and departures, and the National Emissions Inventory for total annual aircraft emissions. We categorized the 47 airports in LA basin based on the volume and type (commercial, general aviation and military) of aircraft traffic, and then assigned appropriate hour-of-day and day-of-week traffic volume-specific CO2 emission patterns to each airport. We found

  16. Point source emission rate estimates from MAMAP airborne remote sensing total column observations of atmospheric CO2 and CH4 (United States)

    Krings, Thomas; Gerilowski, Konstantin; Buchwitz, Michael; Hartmann, Jörg; Sachs, Torsten; Erzinger, Jörg; Burrows, John P.; Bovensmann, Heinrich


    Large parts of the anthropogenic greenhouse gas emissions of CO2 and CH4 are released from localised and point sources such as power plants or as fugitive emissions from fossil fuel mining and production sites. These emissions, however, are often not readily assessed by current measurement systems and networks. A tool developed to better understand point sources of CO2 and CH4 is the optical remote sensing instrument MAMAP (Methane Airborne MAPer), operated from aircraft. After a recent instrument modification, retrievals of the column averaged dry air mole fractions for methane XCH4 (or for carbon dioxide XCO2) derived from MAMAP observations in the short-wave infrared, have a precision of about 0.4% significantly improving data quality. MAMAP total column data also serve as a testbed for inversion concepts for greenhouse gas emissions from point sources using total column atmospheric concentration measurements. As information on wind speed is an important input parameter for the inference of emission rates using MAMAP data, recent measurement campaigns comprised an in-situ wind probe operated onboard the same aircraft. Incorporation of these wind measurements in combination with model data leads to a large reduction of uncertainties on the inversion result. Using the examples of two coal mine ventilation shafts in Western Germany as well as other anthropogenic targets, the value of high resolution total column data to obtain emission rate estimates is demonstrated. MAMAP has also been tested in sunglint geometry over the ocean and has therefore the potential for application also to offshore emission sites.

  17. Application of multiple sorption model to estimation of CO2 sequestration capacity or CH4 recovery in polish hard coals

    Directory of Open Access Journals (Sweden)

    Jodłowski Grzegorz


    Full Text Available The aim of the study is to estimate the theoretical capacity of coal deposits in terms of carbon dioxide storage and methane recovery estimate during the injection of carbon dioxide. The Multiple Sorption Model was used for this purpose. The range of sorption measurement data on which the simulations were based does not exceed the critical point for both methane and carbon dioxide. The model allows to calculate absorption, adsorption, expansion and total theoretical sorption. For further consideration absorption was used as the process of the percolation of the gas in the bulk of the coal matter as well as the total theoretical sorption, the occurrence of which is possible due to the presence of fractures in the coal seam. Calculated levels of absorption and the total theoretical adsorption were applied to estimate the possible storage capacity of carbon dioxide based on the data associated with the content of coal in the mining fields of individual Polish coal mines. Moreover, MSM development for the gas mixture sorption can be used to roughly assess the recovery of methane naturally occurring in coal deposits during such a process.

  18. New data-driven estimation of terrestrial CO2 fluxes in Asia using a standardized database of eddy covariance measurements, remote sensing data, and support vector regression (United States)

    Ichii, Kazuhito; Ueyama, Masahito; Kondo, Masayuki; Saigusa, Nobuko; Kim, Joon; Alberto, Ma. Carmelita; Ardö, Jonas; Euskirchen, Eugénie S.; Kang, Minseok; Hirano, Takashi; Joiner, Joanna; Kobayashi, Hideki; Marchesini, Luca Belelli; Merbold, Lutz; Miyata, Akira; Saitoh, Taku M.; Takagi, Kentaro; Varlagin, Andrej; Bret-Harte, M. Syndonia; Kitamura, Kenzo; Kosugi, Yoshiko; Kotani, Ayumi; Kumar, Kireet; Li, Sheng-Gong; Machimura, Takashi; Matsuura, Yojiro; Mizoguchi, Yasuko; Ohta, Takeshi; Mukherjee, Sandipan; Yanagi, Yuji; Yasuda, Yukio; Zhang, Yiping; Zhao, Fenghua


    The lack of a standardized database of eddy covariance observations has been an obstacle for data-driven estimation of terrestrial CO2 fluxes in Asia. In this study, we developed such a standardized database using 54 sites from various databases by applying consistent postprocessing for data-driven estimation of gross primary productivity (GPP) and net ecosystem CO2 exchange (NEE). Data-driven estimation was conducted by using a machine learning algorithm: support vector regression (SVR), with remote sensing data for 2000 to 2015 period. Site-level evaluation of the estimated CO2 fluxes shows that although performance varies in different vegetation and climate classifications, GPP and NEE at 8 days are reproduced (e.g., r2 = 0.73 and 0.42 for 8 day GPP and NEE). Evaluation of spatially estimated GPP with Global Ozone Monitoring Experiment 2 sensor-based Sun-induced chlorophyll fluorescence shows that monthly GPP variations at subcontinental scale were reproduced by SVR (r2 = 1.00, 0.94, 0.91, and 0.89 for Siberia, East Asia, South Asia, and Southeast Asia, respectively). Evaluation of spatially estimated NEE with net atmosphere-land CO2 fluxes of Greenhouse Gases Observing Satellite (GOSAT) Level 4A product shows that monthly variations of these data were consistent in Siberia and East Asia; meanwhile, inconsistency was found in South Asia and Southeast Asia. Furthermore, differences in the land CO2 fluxes from SVR-NEE and GOSAT Level 4A were partially explained by accounting for the differences in the definition of land CO2 fluxes. These data-driven estimates can provide a new opportunity to assess CO2 fluxes in Asia and evaluate and constrain terrestrial ecosystem models.

  19. Designing a cost-effective CO2 storage infrastructure using a GIS based linear optimization energy model

    NARCIS (Netherlands)

    van den Broek, M.A.|info:eu-repo/dai/nl/092946895; Brederode, E.; Ramírez-Ramírez, A.|info:eu-repo/dai/nl/284852414; Kramers, L.; van der Kuip, M.; Wildenborg, T.; Turkenburg, W.C.|info:eu-repo/dai/nl/073416355; Faaij, A.P.C.|info:eu-repo/dai/nl/10685903X


    Large-scale deployment of carbon capture and storage needs a dedicated infrastructure. Planning and designing of this infrastructure require incorporation of both temporal and spatial aspects. In this study, a toolbox has been developed that integrates ArcGIS, a geographical information system with

  20. Pore-Scale Geochemical Reactivity Associated with CO2 Storage: New Frontiers at the Fluid-Solid Interface. (United States)

    Noiriel, Catherine; Daval, Damien


    The reactivity of carbonate and silicate minerals is at the heart of porosity and pore geometry changes in rocks injected with CO2, which ultimately control the evolution of flow and transport properties of fluids in porous and/or fractured geological reservoirs. Modeling the dynamics of CO2-water-rock interactions is challenging because of the resulting large geochemical disequilibrium, the reservoir heterogeneities, and the large space and time scales involved in the processes. In particular, there is a lack of information about how the macroscopic properties of a reservoir, e.g., the permeability, will evolve as a result of geochemical reactions at the molecular scale. Addressing this point requires a fundamental understanding of how the microstructures influence the macroscopic properties of rocks. The pore scale, which ranges from a few nanometers to centimeters, has stood out as an essential scale of observation of geochemical processes in rocks. Transport or surface reactivity limitations due to the pore space architecture, for instance, are best described at the pore scale itself. It can be also considered as a mesoscale for aggregating and increasing the gain of fundamental understanding of microscopic interfacial processes. Here we focus on the potential application of a combination of physicochemical measurements coupled with nanoscale and microscale imaging techniques during laboratory experiments to improve our understanding of the physicochemical mechanisms that occur at the fluid-solid interface and the dynamics of the coupling between the geochemical reactions and flow and transport modifications at the pore scale. Imaging techniques such as atomic force microscopy, vertical scanning interferometry, focused ion beam transmission electron microscopy, and X-ray microtomography, are ideal for investigating the reactivity dynamics of these complex materials. Minerals and mineral assemblages, i.e., rocks, exhibit heterogeneous and anisotropic reactivity

  1. CO2-neutral fuels

    Directory of Open Access Journals (Sweden)

    Goede A. P. H.


    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

  2. CO2-neutral fuels (United States)

    Goede, A. P. H.


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

  3. Brine migration resulting from CO2 injection into saline aquifers – An approach to risk estimation including various levels of uncertainty

    DEFF Research Database (Denmark)

    Walter, Lena; Binning, Philip John; Oladyshkin, Sergey


    Comprehensive risk assessment is a major task for large-scale projects such as geological storage of CO2. Basic hazards are damage to the integrity of caprocks, leakage of CO2, or reduction of groundwater quality due to intrusion of fluids. This study focuses on salinization of freshwater aquifers...... for large-scale 3D models including complex physics. Therefore, we apply a model reduction based on arbitrary polynomial chaos expansion combined with probabilistic collocation method. It is shown that, dependent on data availability, both types of uncertainty can be equally significant. The presented study...

  4. Inverse Problem for 3D coupled Flow-Geomechanics Models and Induced Seismicity: Application to Subsurface Characterization and Seismicity Forecasting in Geologic CO2 Storage (United States)

    Castineira, D.; Jha, B.; Juanes, R.


    Carbon Capture and Sequestration (CCS) is regarded as a promising technology to mitigate rising CO2 concentrations in the atmosphere from industrial emissions. However, as a result of the inherent uncertainty that is present in geological structures, assessing the stability of geological faults and quantifying the potential for induced seismicity is a fundamental challenge for practical implementation of CCS. Here we present a formal framework for the solution of the inverse problem associated with coupled flow and geomechanics models of CO2 injection and subsurface storage. Our approach builds from the application of Gaussian Processes, MCMC and posterior predictive analysis to evaluate relevant earthquake attributes (earthquake time, location and magnitude) in 3D synthetic models of CO2 storage under geologic, observational and operational uncertainty. In our approach, we first conduct hundreds of simulations of a high-fidelity 3D computational model for CO2 injection into a deep saline aquifer, dominated by an anticline structure and a fault. This ensemble of realizations accounts for uncertainty in the model parameters (including fault geomechanical and rock properties) and observations (earthquake time, location and magnitude). We apply Gaussian processes (GP) to generate a valid surrogate that closely approximates the behavior of the high fidelity (and computationally intensive) model, and apply hyperparameter optimization and cross-validation techniques in the solution of this multidimensional data-fit problem. The net result of this process is the generation of a fast model that can be effectively used for Bayesian analysis. We then implement Markov chain Monte Carlo (MCMC) to determine the posterior distribution of the model uncertain parameters (given some prior distributions for those parameters and given the likelihood defined in this case by the GP model). Our results show that the resulting posterior distributions correctly converge towards the "true

  5. The effects of gas-fluid-rock interactions on CO2 injection and storage: Insights from reactive transport modeling

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Y.; Xu, T.; Pruess, K.


    Possible means of reducing atmospheric CO{sub 2} emissions include injecting CO{sub 2} in petroleum reservoirs for Enhanced Oil Recovery or storing CO{sub 2} in deep saline aquifers. Large-scale injection of CO{sub 2} into subsurface reservoirs would induce a complex interplay of multiphase flow, capillary trapping, dissolution, diffusion, convection, and chemical reactions that may have significant impacts on both short-term injection performance and long-term fate of CO{sub 2} storage. Reactive Transport Modeling is a promising approach that can be used to predict the spatial and temporal evolution of injected CO{sub 2} and associated gas-fluid-rock interactions. This presentation will summarize recent advances in reactive transport modeling of CO{sub 2} storage and review key technical issues on (1) the short- and long-term behavior of injected CO{sub 2} in geological formations; (2) the role of reservoir mineral heterogeneity on injection performance and storage security; (3) the effect of gas mixtures (e.g., H{sub 2}S and SO{sub 2}) on CO{sub 2} storage; and (4) the physical and chemical processes during potential leakage of CO{sub 2} from the primary storage reservoir. Simulation results suggest that CO{sub 2} trapping capacity, rate, and impact on reservoir rocks depend on primary mineral composition and injecting gas mixtures. For example, models predict that the injection of CO{sub 2} alone or co-injection with H{sub 2}S in both sandstone and carbonate reservoirs lead to acidified zones and mineral dissolution adjacent to the injection well, and carbonate precipitation and mineral trapping away from the well. Co-injection of CO{sub 2} with H{sub 2}S and in particular with SO{sub 2} causes greater formation alteration and complex sulfur mineral (alunite, anhydrite, and pyrite) trapping, sometimes at a much faster rate than previously thought. The results from Reactive Transport Modeling provide valuable insights for analyzing and assessing the dynamic

  6. First Modelling Results of the EM Response of a CO2 Storage in the Paris Basin Premières modélisations de la réponse EM d’un stockage de CO2 dans le bassin Parisien

    Directory of Open Access Journals (Sweden)

    Bourgeois B.


    aquifer. A uniform CO2 saturation of 80% is assumed, yielding a resistivity contrast of 25 with the initial reservoir. Two variants of the model with different reservoir resistivities are compared. The first model is calculated with a realistic reservoir resistivity of 20 ohm.m, reflecting the low salinity of the aquifer in this part of the Basin (≈ g g/L of NaCl. With this model, the time-lapse electric response of the CO2 plume is less than 0.5% of the initial electric field, which is below the estimated “repetition noise”. This poor result can be explained by the fact that the reservoir, in this case, is far from being the most conductive layer of the model. As a consequence, only a minor part of the injected current is used for energizing the CO2 plume: a rough calculation shows that only about 2% of the injected current crosses the reservoir, hence the poor response of the plume. A second model is calculated with an idealistic reservoir resistivity of 1 ohm.m, corresponding to about 50-70 g/L of NaCl in the aquifer (though such salinity is not observed anywhere in the Dogger aquifer of the Paris Basin, it is common in many storage aquifers. With this favourable model, it is estimated that about 30% of the injected current crosses the reservoir and energizes the plume, resulting in a time-lapse electric response as high as 6% of the initial field, which is quite measurable. For comparison, the timelapse electric response obtained with the same model for a surface current injection (RECT array is only 2% of the initial field. With this same model, the time-lapse magnetic response obtained for the LEMAM injection is about 3% of the initial magnetic field. We conclude that the LEMAM array is very promising for the resistivity monitoring of a CO2 injection in a deep aquifer, provided that the water salinity is high enough for the reservoir to channel a significant fraction of the injected current (say > 10%. Nous etudions la possibilite d’utiliser les methodes

  7. Fabrication of cubic spinel MnCo2O4 nanoparticles embedded in graphene sheets with their improved lithium-ion and sodium-ion storage properties (United States)

    Chen, Chang; Liu, Borui; Ru, Qiang; Ma, Shaomeng; An, Bonan; Hou, Xianhua; Hu, Shejun


    Cubic Spinel MnCo2O4/graphene sheets (MCO/GS) nanocomposites are synthesized by a facile hydrothermal method with a subsequent annealing process. Nano-sized MnCo2O4 particles are evenly embedded in paper-like graphene sheets, possessing a unique nanoparticles-on-sheets hybrid nanostructure, with particle size around 20-50 nm. Owing to the special nanoparticles-on-sheets structures, MCO/GS nanocomposites have an outstanding electrochemical performance for rechargeable energy storage devices. As an anode material for lithium-ion batteries, MCO/GS electrodes exhibit high reversible discharge capacities (1350.4 mAh g-1 at the initial rate of 100 mA g-1), excellent rate capability (462.1 mAh g-1 at a current rate of 4000 mA g-1) and outstanding cycling performance (584.3 mAh g-1 at 2000 mA g-1 after 250 cycles). Meanwhile, as an anode material for sodium-ion batteries, MCO/GS electrodes also exhibit comparably promising electrochemical characteristics. Greatly improved electrochemical properties can be assigned to the special advantageous nanostructures. Besides, the existence of graphene sheets is beneficial to the transportation of ions/electrons during battery operation. The outstanding electrochemical performance demonstrates that the lithium/sodium storage capability of MCO/GS nanocomposites is highly promising for high-capacity batteries.

  8. Super-chilling (-0.7°C) with high-CO2 packaging inhibits biochemical changes of microbial origin in catfish (Clarias gariepinus) muscle during storage. (United States)

    Zhu, Yingchun; Ma, Lizhen; Yang, Hua; Xiao, Yan; Xiong, Youling L


    Controlled freezing-point storage (CFPS) is an emerging preservative technique desirable for fish. In the present study, catfish fillets were stored at -0.7°C under different packaging atmospheres: air (AP), vacuum (VP), and 60% CO2/40% N2 (MAP). Chemical, microbiological, and sensory analyses were performed during storage. Results showed the following descending order of chemical changes (degradation of nucleotides, conversion of protein to volatile-based nitrogen and biogenic amines, and production of trimethylamine nitrogen), as well as loss of sensory properties: 4°C AP>-0.7°C AP≈4°C VP>-0.7°C VP≈4°C MAP>-0.7°C MAP. The chemical changes were well-correlated with microbial growth suggesting the microbiological pathways. Hence, CFPS at -0.7°C in combination with high-CO2 MAP can effectively maintain the quality of fresh catfish meat compared to traditional preservation methods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Validity of the doubly labeled water method for estimating CO2 production in mice under different nutritional conditions

    NARCIS (Netherlands)

    Guidotti, Stefano; Meijer, Harro A. J.; van Dijk, Gertjan

    The doubly labeled water (DLW) technique is used to assess metabolic rate (MR) in free-living conditions. We investigated whether differences in the nutritional and body adiposity status affect validity of the assessment of CO2 production (rCO(2)) by the DLW technique. To serve this purpose, we

  10. A Comparative Review of Hydrologic Issues Involved in Geologic Storage of CO2 and Injection Disposal of Liquid Waste

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, C.-F.; Birkholzer, J.; Rutqvist, J.


    The paper presents a comparison of hydrologic issues and technical approaches used in deep-well injection and disposal of liquid wastes, and those issues and approaches associated with injection and storage of CO{sub 2} in deep brine formations. These comparisons have been discussed in nine areas: (1) Injection well integrity; (2) Abandoned well problems; (3) Buoyancy effects; (4) Multiphase flow effects; (5) Heterogeneity and flow channeling; (6) Multilayer isolation effects; (7) Caprock effectiveness and hydrogeomechanics; (8) Site characterization and monitoring; and (9) Effects of CO{sub 2} storage on groundwater resources There are considerable similarities, as well as significant differences. Scientifically and technically, these two fields can learn much from each other. The discussions presented in this paper should help to focus on the key scientific issues facing deep injection of fluids. A substantial but by no means exhaustive reference list has been provided for further studies into the subject.

  11. From Injectivity to Integrity Studies of CO2 Geological Storage Caractérisation de l’injectivité et de l’intégrité d’un stockage géologique de CO2

    Directory of Open Access Journals (Sweden)

    Bemer E.


    Full Text Available The technical and economical success of a CO2 geological storage project requires the preservation of the site injectivity and integrity properties over its lifetime. Unlike conventional hydrocarbon gas injection, CO2 injection implies geochemical reactions between the reactive brine and the in situ formations (reservoir and cap rock leading to modifications of their petrophysical and geomechanical properties. This paper underlines the experimental difficulties raised by the low permeability of samples representative either of the cap rock itself or at least of transition zones between the reservoir and the effective cap rock. Acidification effects induced by CO2 injection have been studied using an experimental procedure of chemical alteration, which ensures a homogeneous dissolution pattern throughout the rock sample and especially avoids any wormholing process that would lead to erroneous measurements at the core scale. Porosity, permeability and geomechanical properties of outcrop and field carbonate samples of various permeability levels have been measured under their native state and different levels of alteration. The present work has been conducted within the framework of ANR GeoCarbone-INJECTIVITY and GeoCarbone-INTEGRITY projects. Each experimental step: chemical alteration, petrophysical measurements and geomechanical testing, is considered from the point of view of injectivity and integrity issues. The obtained experimental data show clear trends of chemically induced mechanical weakening. La réussite technique et économique d’un projet de stockage géologique de CO2 repose sur le maintien des propriétés d’injectivité et d’intégrité du site pendant sa durée de vie. Contrairement à l’injection d’un gaz d’hydrocarbure standard, l’injection de CO2 implique des réactions géochimiques entre la saumure réactive mobile et les roches en place (réservoir et couverture conduisant à des modifications de leurs propri

  12. Effects of brine displacement on pressure and salinity increases in a regional freshwater aquifer complex with respect to CO2 storage in saline subsurface formations (United States)

    Janetz, Silvio; Jahnke, Christoph; Tillner, Elena; Kempka, Thomas; Röhmann, Lina; Kühn, Michael


    The geological storage of CO2 in deep saline aquifers may cause upward migration of displaced brines along leakage pathways such as highly-transmissive faults due to an increasing pore pressure in the storage formation. Besides the risk of CO2 leakage, the protection of the shallow freshwater reservoirs from upward migrating brine is a requirement with regard to environmental compatibility of future CCS projects. In the present study, the regional impact of pressure build-up and salinity increases in a freshwater reservoir induced by brine displacement due to CO2 injection into saline subsurface formations was investigated. A multi-layered aquifer-aquitard system of Triassic to Cenozoic age was used as a framework to ensure that realistic hydrodynamic and hydrochemical conditions were applied in this assessment. The prospective storage horizon corresponding to a Lower Triassic sandstone aquifer is located in a broad anticlinal structure at the southeastern margin of the Northeast German Basin. This intracontinental basin is not only characterised by large salinity gradients but also by hydrogeologically significant fault zones and glacial erosional structures that may act as migration pathways for saline formation water into Cenozoic freshwater reservoirs. In a first step, a detailed three-dimensional geological model was implemented. The model has a horizontal extent of 73 km (N-S) × 85 km (E-W) and a vertical extent of 2.4 km. In a second step, the geological model was transferred into a hydrogeological model by discretisation and parameterisation using data obtained from borehole measurements, field observations and geological maps. The modelling was performed using the FEFLOW FMH3® code. Long-term transport simulations with NaCl as a tracer were conducted to comprehend the natural freshwater-saltwater distribution of the regional aquifer system. Based on these initial conditions, simulations of possible upward brine migration into a freshwater aquifer complex

  13. Risk, liability, and economic issues with long-term CO2 storage—A review (United States)

    Anderson, Steven T.


    Given a scarcity of commercial-scale carbon capture and storage (CCS) projects, there is a great deal of uncertainty in the risks, liability, and their cost implications for geologic storage of carbon dioxide (CO2). The probabilities of leakage and the risk of induced seismicity could be remote, but the volume of geologic CO2 storage (GCS) projected to be necessary to have a significant impact on increasing CO2 concentrations in the atmosphere is far greater than the volumes of CO2 injected thus far. National-level estimates of the technically accessible CO2storage resource (TASR) onshore in the United States are on the order of thousands of gigatons of CO2 storage capacity, but such estimates generally assume away any pressure management issues. Pressure buildup in the storage reservoir is expected to be a primary source of risk associated with CO2 storage, and only a fraction of the theoretical TASR could be available unless the storage operator extracts the saltwater brines or other formation fluids that are already present in the geologic pore space targeted for CO2 storage. Institutions, legislation, and processes to manage the risk, liability, and economic issues with CO2 storage in the United States are beginning to emerge, but will need to progress further in order to allow a commercial-scale CO2 storage industry to develop in the country. The combination of economic tradeoffs, property rights definitions, liability issues, and risk considerations suggests that CO2 storage offshore of the United States may be more feasible than onshore, especially during the current (early) stages of industry development.

  14. Binary cooperative NiCo2O4 on the nickel foams with quasi-two-dimensional precursors: a bridge between 'supercapacitor' and 'battery' in electrochemical energy storage. (United States)

    Peng, Tao; Qian, Zhongyu; Wang, Jun; Qu, Liangti; Wang, Peng


    Some inorganic quasi-two-dimensional nanomaterials such as cobalt-nickel hydroxides are kinetically facile for a capacitive charge storage process. However, high performance capacitive charge storage needs a balance of the ionic and electronic transporting, and to build up an integrated architecture on substrates step by step and utilize the interface better is still a key challenge. As the interfacial assembly has conflicted with our goals for high-performance capacitive charge storage process, we identify theoretically and experimentally binary cooperative nanoscale interfacial materials to solve the problem. Co-Ni-hydroxide precursors were prepared by hybrid quasi-two-dimensional nanosheets and hetero-oriented nanocrystallines walls. Followed by dip-dry and annealing, NiCo2O4 could adhere to the nickel foams robustly with a solution-based surface treatment. Moreover, an unusual phenomenon in the electrochemical test inspired us to establish a bridge between 'supercapacitor' and 'battery'. The bridged gap highlights a new design idea for high-performance energy storage.

  15. Theoretical reconsiderations when estimating the mesophyll conductance to CO2 diffusion in leaves of C3 plants by analysis of combined gas exchange and chlorophyll fluorescence measurements

    NARCIS (Netherlands)

    Yin, X.; Struik, P.C.


    Existing methods to estimate the mesophyll conductance to CO2 diffusion (gm) are often based on combined gas exchange and chlorophyll fluorescence measurements. However, estimations of average gm by these methods are often unreliable either because the range of usable data is too narrow or because

  16. Estimation of the fossil fuel component in atmospheric CO2 based on radiocarbon measurements at the Beromünster tall tower, Switzerland (United States)

    Berhanu, Tesfaye A.; Szidat, Sönke; Brunner, Dominik; Satar, Ece; Schanda, Rüdiger; Nyfeler, Peter; Battaglia, Michael; Steinbacher, Martin; Hammer, Samuel; Leuenberger, Markus


    Fossil fuel CO2 (CO2ff) is the major contributor of anthropogenic CO2 in the atmosphere, and accurate quantification is essential to better understand the carbon cycle. Since October 2012, we have been continuously measuring the mixing ratios of CO, CO2, CH4, and H2O at five different heights at the Beromünster tall tower, Switzerland. Air samples for radiocarbon (Δ14CO2) analysis have also been collected from the highest sampling inlet (212.5 m) of the tower on a biweekly basis. A correction was applied for 14CO2 emissions from nearby nuclear power plants (NPPs), which have been simulated with the Lagrangian transport model FLEXPART-COSMO. The 14CO2 emissions from NPPs offset the depletion in 14C by fossil fuel emissions, resulting in an underestimation of the fossil fuel component in atmospheric CO2 by about 16 %. An average observed ratio (RCO) of 13.4 ± 1.3 mmol mol-1 was calculated from the enhancements in CO mixing ratios relative to the clean-air reference site Jungfraujoch (ΔCO) and the radiocarbon-based fossil fuel CO2 mole fractions. The wintertime RCO estimate of 12.5 ± 3.3 is about 30 % higher than the wintertime ratio between in situ measured CO and CO2 enhancements at Beromünster over the Jungfraujoch background (8.7 mmol mol-1) corrected for non-fossil contributions due to strong biospheric contribution despite the strong correlation between ΔCO and ΔCO2 in winter. By combining the ratio derived using the radiocarbon measurements and the in situ measured CO mixing ratios, a high-resolution time series of CO2ff was calculated exhibiting a clear seasonality driven by seasonal variability in emissions and vertical mixing. By subtracting the fossil fuel component and the large-scale background, we have determined the regional biospheric CO2 component that is characterized by seasonal variations ranging between -15 and +30 ppm. A pronounced diurnal variation was observed during summer modulated by biospheric exchange and vertical mixing, while no

  17. The Ohio River Valley CO2 Storage Project AEP Mountaineer Plant, West Virginia Numerical Simulation and Risk Assessment Report

    Energy Technology Data Exchange (ETDEWEB)

    Neeraj Gupta


    A series of numerical simulations of carbon dioxide (CO{sub 2}) injection were conducted as part of a program to assess the potential for geologic sequestration in deep geologic reservoirs (the Rose Run and Copper Ridge formations), at the American Electric Power (AEP) Mountaineer Power Plant outside of New Haven, West Virginia. The simulations were executed using the H{sub 2}O-CO{sub 2}-NaCl operational mode of the Subsurface Transport Over Multiple Phases (STOMP) simulator (White and Oostrom, 2006). The objective of the Rose Run formation modeling was to predict CO{sub 2} injection rates using data from the core analysis conducted on the samples. A systematic screening procedure was applied to the Ohio River Valley CO{sub 2} storage site utilizing the Features, Elements, and Processes (FEP) database for geological storage of CO{sub 2} (Savage et