To achieve carbon dioxide(CO_(2))storage through enhanced oil recovery,accurate forecasting of CO_(2) subsurface storage and cumulative oil production is essential.This study develops hybrid predictive models for the ...To achieve carbon dioxide(CO_(2))storage through enhanced oil recovery,accurate forecasting of CO_(2) subsurface storage and cumulative oil production is essential.This study develops hybrid predictive models for the determination of CO_(2) storage mass and cumulative oil production in unconventional reservoirs.It does so with two multi-layer perceptron neural networks(MLPNN)and a least-squares support vector machine(LSSVM),hybridized with grey wolf optimization(GWO)and/or particle swarm optimization(PSO).Large,simulated datasets were divided into training(70%)and testing(30%)groups,with normalization applied to both groups.Mahalanobis distance identifies/eliminates outliers in the training subset only.A non-dominated sorting genetic algorithm(NSGA-II)combined with LSSVM selected seven influential features from the nine available input parameters:reservoir depth,porosity,permeability,thickness,bottom-hole pressure,area,CO_(2) injection rate,residual oil saturation to gas flooding,and residual oil saturation to water flooding.Predictive models were developed and tested,with performance evaluated with an overfitting index(OFI),scoring analysis,and partial dependence plots(PDP),during training and independent testing to enhance model focus and effectiveness.The LSSVM-GWO model generated the lowest root mean square error(RMSE)values(0.4052 MMT for CO_(2) storage and 9.7392 MMbbl for cumulative oil production)in the training group.That trained model also exhibited excellent generalization and minimal overfitting when applied to the testing group(RMSE of 0.6224 MMT for CO_(2) storage and 12.5143 MMbbl for cumulative oil production).PDP analysis revealed that the input features“area”and“porosity”had the most influence on the LSSVM-GWO model's pre-diction performance.This paper presents a new hybrid modeling approach that achieves accurate forecasting of CO_(2) subsurface storage and cumulative oil production.It also establishes a new standard for such forecasting,which can lead to the development of more effective and sustainable solutions for oil recovery.展开更多
The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the informatio...The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the information of formation pressure can be response in the seismic data. Therefore, it is possible to monitor the formation pressure using time-lapse seismic method. Apart from formation pressure, the information of porosity and CO_(2) saturation can be reflected in the seismic data. Here, based on the actual situation of the work area, a rockphysical model is proposed to address the feasibility of time-lapse seismic monitoring during CO_(2) storage in the anisotropic formation. The model takes into account the formation pressure, variety minerals composition, fracture, fluid inhomogeneous distribution, and anisotropy caused by horizontal layering of rock layers(or oriented alignment of minerals). From the proposed rockphysical model and the well-logging, cores and geological data at the target layer, the variation of P-wave and S-wave velocity with formation pressure after CO_(2) injection is calculated. And so are the effects of porosity and CO_(2) saturation. Finally, from anisotropic exact reflection coefficient equation, the reflection coefficients under different formation pressures are calculated. It is proved that the reflection coefficient varies with pressure. Compared with CO_(2) saturation, the pressure has a greater effect on the reflection coefficient. Through the convolution model, the seismic record is calculated. The seismic record shows the difference with different formation pressure. At present, in the marine CO_(2) sequestration monitoring domain, there is no study involving the effect of formation pressure changes on seismic records in seafloor anisotropic formation. This study can provide a basis for the inversion of reservoir parameters in anisotropic seafloor CO_(2) reservoirs.展开更多
Carbon dioxide(CO2) capture and storage(CCS) is considered widely as one of promising options for CO2emissions reduction,especially for those countries with coal-dominant energy mix like China.Injecting and storing a ...Carbon dioxide(CO2) capture and storage(CCS) is considered widely as one of promising options for CO2emissions reduction,especially for those countries with coal-dominant energy mix like China.Injecting and storing a huge volume of CO2in deep formations are likely to cause a series of geomechanical issues,including ground surface uplift,damage of caprock integrity,and fault reactivation.The Shenhua CCS demonstration project in Ordos Basin,China,is the first and the largest full-chain saline aquifer storage project of CO2in Asia.The injection started in 2010 and ended in 2015.during which totally 0.3 million tonnes(Mt) CO2was injected.The project is unique in which CO2was injected into 18 sandstone formations simultaneously and the overlying coal seams will be mined after the injection stopped in 2015.Hence,intense geomechanical studies and monitoring works have been conducted in recent years,including possible damage resulting from the temperature difference between injected CO2and formations,injection induced stress and deformation change,potential failure mode and safety factor,interaction between coal mining and CO2geological storage,determination of injection pressure limit,and surface monitoring by the interferometric synthetic aperture radar(InSAR) technology.In this paper,we first described the background and its geological conditions of the Shenhua CCS demonstration project.Then,we gave an introduction to the coupled thermo-hydro-mechano-chemical(THMC) processes in CO2geological storage,and mapped the key geomechanical issues into the THMC processes accordingly.Next,we proposed a generalized geomechanical research flowchart for CO2geological storage projects.After that,we addressed and discussed some typical geomechanical issues,including design of injection pressure limit.CO2injection induced near-field damage,and interaction between CO2geological storage and coal mining,in the Shenhua CCS demonstration project.Finally,we concluded some insights to this CCS project.展开更多
The development history of carbon capture,utilization and storage for enhanced oil recovery(CCUS-EOR)in China is comprehensively reviewed,which consists of three stages:research and exploration,field test and industri...The development history of carbon capture,utilization and storage for enhanced oil recovery(CCUS-EOR)in China is comprehensively reviewed,which consists of three stages:research and exploration,field test and industrial application.The breakthrough understanding of CO_(2) flooding mechanism and field practice in recent years and the corresponding supporting technical achievements of CCUS-EOR project are systematically described.The future development prospects are also pointed out.After nearly 60 years of exploration,the theory of CO_(2) flooding and storage suitable for continental sedimentary reservoirs in China has been innovatively developed.It is suggested that C7–C15 are also important components affecting miscibility of CO_(2) and crude oil.The mechanism of rapid recovery of formation energy by CO_(2) and significant improvement of block productivity and recovery factor has been verified in field tests.The CCUS-EOR reservoir engineering design technology for continental sedimentary reservoir is established.The technology of reservoir engineering parameter design and well spacing optimization has been developed,which focuses on maintaining miscibility to improve oil displacement efficiency and uniform displacement to improve sweep efficiency.The technology of CO_(2) capture,injection and production process,whole-system anticorrosion,storage monitoring and other whole-process supporting technologies have been initially formed.In order to realize the efficient utilization and permanent storage of CO_(2),it is necessary to take the oil reservoir in the oil-water transition zone into consideration,realize the large-scale CO_(2) flooding and storage in the area from single reservoir to the overall structural control system.The oil reservoir in the oil-water transition zone is developed by stable gravity flooding of injecting CO_(2) from structural highs.The research on the storage technology such as the conversion of residual oil and CO_(2) into methane needs to be carried out.展开更多
The transition to a non-emitting energy mix for power generation will take decades. This transition will need to be sustainable, e.g.economically affordable. Fossil fuels which are abundant have an important role to p...The transition to a non-emitting energy mix for power generation will take decades. This transition will need to be sustainable, e.g.economically affordable. Fossil fuels which are abundant have an important role to play in this respect, provided that Carbon Capture and Storage(CCS) is progressively implemented. CCS is the only way to reduce emissions from energy intensive industries.Thus, the need for upgraded and new CCS research facilities is widely recognised among stakeholders across Europe, as emphasised by the Zero Emissions Platform(ZEP) [1] and the European Energy Research Alliance on CCS(EERA-CCS) [2].The European Carbon Dioxide Capture and Storage Laboratory Infrastructure, ECCSEL, provides funders, operators and researchers with significant benefits by offering access to world-class research facilities that, in many cases, are unlikely for a single nation to support in isolation.This implies creation of synergy and the avoidance of duplication as well as streamlining of funding for research facilities.ECCSEL offers open access to its advanced laboratories for talented scientists and visiting researchers to conduct cutting-edge research.In the planning of ECCSEL, gap analyses were performed and CCS technologies have been reviewed to underpin and envisage the future experimental setup; 1) Making use of readily available facilities, 2) Modifying existing facilities, and 3) Planning and building entirely new advanced facilities.The investments required for the first ten years(2015-2025) are expected to be in the range of €80-120 miilion. These investments show the current level of ambition, as proposed during the preparatory phase(2011-2014).Entering the implementation phase in 2015, 9 European countries signed Letter of Intent(LoI) to join a ECCSEL legal entity: France, United Kingdom, Netherlands, Italy, Spain, Poland, Greece, Norway and Switzerland(active observer). As the EU ERIC-regulation [3] would offer the most suitable legal framework for ECCSEL, the host country, Norway, will apply for establishing ERIC as the ECCSEL Research Infrastructure(RI)legal entity in 2017. Until the ECCSEL ERIC is approved by the European Commission(probably by summer 2017), an interim MoU agreement for the implementation phase of ECCSEL RI has been signed by 13 research institutions and universities representing the 9 countries. A consortium of these partners were granted 3 million EURO from Horizon 2020 to boost implementation of ECCSEL from September 2015 and two years onwards.?2016, Institute of Process Engineering, Chinese Academy of Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).展开更多
Continuous accumulation and emission into the atmosphere of anthropogenic carbon dioxide(CO_(2)),a major greenhouse gas,has been recognized as a primary contributor to climate change associated with the global warming...Continuous accumulation and emission into the atmosphere of anthropogenic carbon dioxide(CO_(2)),a major greenhouse gas,has been recognized as a primary contributor to climate change associated with the global warming and acidification of oceans.This has led to drastic changes in the natural ecosystem,and hence an unhealthy ecological environment for human society.Thus,the effective mitigation of the ever increasing CO_(2)emission has been recognized as the most important global challenge.To achieve zero carbon footprint,novel materials and approaches are required for potentially reducing the CO_(2)release,while our current fossil-fuel-based energy must be replaced by renewable energy free from emissions.In this paper,porous carbons with hierarchical pore structures are promising for CO_(2)adsorption and electrochemical CO_(2)reduction owing to their high specific surface area,excellent catalytic performance,low cost and long-term stability.Since efficient gas-phased(electro)catalysis involves the access of reactants to active sites at the gas-liquid-solid triple phase,the hierarchical porous carbon materials possess multiple advantages for various CO_(2)-related applications with enhanced volumetric and gravimetric activities(e.g.,CO_(2)uptake and current density)for practical operations.Recent studies have demonstrated that porous carbon materials exhibited notable activities as CO_(2)adsorbents and provided facile conducting pathways and mass diffusion channels for efficient electrochemical CO_(2)reduction even under the high current operation conditions.Herein,we summarize recent advances in porous carbon materials for CO_(2)capture,storage,and electrochemical conversion.Prospectives and challenges on the rational design of porous carbon materials for scalable and practical CO_(2)capture and conversion are also discussed.展开更多
Research progress is required to be enhanced for those storage technologies which store CO_(2)fast and permanently.However,temporary storage technologies importance cannot be denied to immediately reduce global warmin...Research progress is required to be enhanced for those storage technologies which store CO_(2)fast and permanently.However,temporary storage technologies importance cannot be denied to immediately reduce global warming and reduce higher CO_(2)concentration in the atmosphere.Continuous CO_(2)storage facilities,semi-batch and batch pilot plants deemed necessary to build for future survival of the earth planet.Membranes can be used to separate CO_(2)from common flue gases followed by mineral carbonation to convert CO_(2)into stable carbonates.Modifications in cement industry,coal fired power plants,fertilizer industries and other chemical process industries appears essential.展开更多
The development and deployment of Carbon dioxide Capture and Storage （CCS） technology is a cornerstone of the Norwegian government＇s climate strategy. A number of projects are currently evaluated/planned along the ...The development and deployment of Carbon dioxide Capture and Storage （CCS） technology is a cornerstone of the Norwegian government＇s climate strategy. A number of projects are currently evaluated/planned along the Norwegian West Coast, one at Tjeldbergodden. COe from this project will be utilized in part for enhanced oil recovery in the Halten oil field, in the Norwegian Sea. We study a potential design of such a system. A combined cycle power plant with a gross power output of 832 MW is combined with CO2 capture plant based on a post-combustion capture using amines as a solvent. The captured CO2 is used for enhanced oil recovery （EOR）. We employ a hybrid life-cycle assessment （LCA） method to assess the environmental impacts of the system. The study focuses on the modifications and operations of the platform during EOR. We allocate the impacts connected to the capture of CO2 to electricity production, and the impacts connected to the transport and storage of CO2 to the oil produced. Our study shows a substantial reduction of the greenhouse gas emissions from power production by 80% to 75 g·（kW·h）^-1. It also indicates a reduction of the emissions associated with oil production per unit oil produced, mostly due to the increased oil production. Reductions are especially significant if the additional power demand due to EOR leads to power supply from the land.展开更多
The use of sequestered carbon dioxide(CO) as the heat exchange fluid in enhanced geothermal system(EGS) has significant potential to increase their productivity, contribute further to reducing carbon emissions and inc...The use of sequestered carbon dioxide(CO) as the heat exchange fluid in enhanced geothermal system(EGS) has significant potential to increase their productivity, contribute further to reducing carbon emissions and increase the economic viability of geothermal power generation. Coupled COsequestration and geothermal energy production from hot dry rock(HDR) EGS were first proposed 15 years ago but have yet to be practically implemented. This paper reviews some of the issues in assessing these systems with particular focus on the power generation and COsequestration capacity. The Habanero geothermal field in the Cooper Basin of South Australia is assessed for its potential COstorage capacity if supercritical COis used as the working fluid for heat extraction. The analysis suggests that the major COsequestration mechanisms are the storage in the fracture-stimulation damaged zone followed by diffusion into the pores within the rock matrix. The assessment indicates that 5% of working fluid loss commonly suggested as the storage capacity might be an over-estimate of the long-term COsequestration capacity of EGS in which supercritical COis used as the circulation fluid.展开更多
Important first phases in the process of implementing CO2 subsurface and ocean storage projects include selecting of best possible location(s) for CO2 storage, and site selection evaluation. Sites must fulfill a numbe...Important first phases in the process of implementing CO2 subsurface and ocean storage projects include selecting of best possible location(s) for CO2 storage, and site selection evaluation. Sites must fulfill a number of criteria that boil down to the following basics: they must be able to accept the desired volume of CO2 at the rate at which it is supplied from the CO2 source(s);they must as well be safe and reliable;and must comply with regulatory and other societal requirements. They also must have at least public acceptance and be based on sound financial analysis. Site geology;hydrogeological, pressure, and geothermal regimes;land features;location, climate, access, etc. can all be refined from these basic criteria. In addition to aiding in site selection, site characterization is essential for other purposes, such as foreseeing the fate and impacts of the injected CO2, and informing subsequent phases of site development, including design, permitting, operation, monitoring, and eventual abandonment. According to data from the IEA, in 2022, emissions from Africa and Asias emerging markets and developing economies, excluding Chinas, increased by 4.2%, which is equivalent to 206 million tonnes of CO2 and were higher than those from developed economies. Coal-fired power generation was responsible for more than half of the rise in emissions that were recorded in the region. The difficulty of achieving sustainable socio-economic progress in the developing countries is entwined with the work of reducing CO2 emissions, which is a demanding project for the economy. Organisations from developing countries, such as Bangladesh, Cameroon, India, and Nigeria, have formed partnerships with organisations in other countries for lessons learned and investment within the climate change arena. The basaltic rocks, coal seams, depleted oil and gas reservoirs, soils, deep saline aquifers, and sedimentary basins that developing countries (Bangladesh, Cameroon, India, and Nigeria etc.) possess all contribute to the individual countrys significant geological sequestration potential. There are limited or no carbon capture and storage or clean development mechanism projects running in these countries at this time. The site selection and characterization procedure are not complete without an estimate of the storage capacity of a storage location. Estimating storage capacity relies on volumetric estimates because a site must accept the planned volume of CO2 during the active injection period. As more and more applications make use of site characterization, so too does the body of written material on the topic. As the science of CO2 storage develops, regulatory requirements are implemented, field experience grows, and the economics of CO2 capture and storage improve, so too will site selection and characterisation change.展开更多
Offshore carbon dioxide(CO_(2)) storage is an effective method for reducing greenhouse gas emissions. However, when using traditional seismic wave methods to monitor the migration of sequestration CO_(2) plumes, the c...Offshore carbon dioxide(CO_(2)) storage is an effective method for reducing greenhouse gas emissions. However, when using traditional seismic wave methods to monitor the migration of sequestration CO_(2) plumes, the characteristics of wave velocity changes tend to become insignificant beyond a certain limit. In contrast, the controllable source electromagnetic method(CSEM) remains highly sensitive to resistivity changes. By simulating different CO_(2) plume migration conditions, we established the relevant models and calculated the corresponding electric field response characteristic curves, allowing us to analyze the CSEM's ability to monitor CO_(2) plumes. We considered potential scenarios for the migration and diffusion of offshore CO_(2) storage, including various burial depths, vertical extension diffusion, lateral extension diffusion,multiple combinations of lateral intervals, and electric field components. We also obtained differences in resistivity inversion imaging obtained by CSEM to evaluate its feasibility in monitoring and to analyze all the electric field(Ex, Ey, and Ez) response characteristics. CSEM has great potential in monitoring CO_(2) plume migration in offshore saltwater reservoirs due to its high sensitivity and accuracy. Furthermore, changes in electromagnetic field response reflect the transport status of CO_(2) plumes, providing an important basis for monitoring and evaluating CO_(2)transport behavior during storage processes.展开更多
Carbon dioxide energy storage(CES)is an emerging compressed gas energy storage technology which offers high energy storage efficiency,flexibility in location,and low overall costs.This study focuses on a CES system th...Carbon dioxide energy storage(CES)is an emerging compressed gas energy storage technology which offers high energy storage efficiency,flexibility in location,and low overall costs.This study focuses on a CES system that incorporates a high-temperature graded heat storage structure,utilizing multiple heat exchange working fluids.Unlike traditional CES systems that utilize a single thermal storage at low to medium temperatures,this system significantly optimizes the heat transfer performance of the system,thereby improving its cycle efficiency.Under typical design conditions,the round-trip efficiency of the system is found to be 76.4%,with an output power of 334 kW/(kg·s^(-1))per unit mass flow rate,through mathematical modeling.Performance analysis shows that increasing the total pressure ratio,reducing the heat transfer temperature difference,improving the heat exchanger efficiency,and lowering the ambient temperature can enhance cycle efficiency.Additionally,this paper proposes a universal and theoretical CES thermodynamic intrinsic cycle construction method and performance prediction evaluation method for CES systems,providing a more standardized and accurate approach for optimizing CES system design.展开更多
This paper focuses on the progress in geomechanical modeling associated with carbon dioxide(CO2)geological storage.The detailed review of some geomechanical aspects,including numerical methods,stress analysis,ground d...This paper focuses on the progress in geomechanical modeling associated with carbon dioxide(CO2)geological storage.The detailed review of some geomechanical aspects,including numerical methods,stress analysis,ground deformation,fault reactivation,induced seismicity and crack propagation,is presented.It is indicated that although all the processes involved are not fully understood,integration of all available data,such as ground survey,geological conditions,microseismicity and ground level deformation,has led to many new insights into the rock mechanical response to CO2injection.The review also shows that in geomechanical modeling,continuum modeling methods are predominant compared with discontinuum methods.It is recommended to develop continuum-discontinuum numerical methods since they are more convenient for geomechanical modeling of CO2geological storage,especially for fracture propagation simulation.The Mohr-Coulomb criterion is widely used in prediction of rock mass mechanical behavior.It would be better to use a criterion considering the effect of the intermediate principal stress on rock mechanical behavior,especially for the stability analysis of deeply seated rock engineering.Some challenges related to geomechanical modeling of CO2geological storage are also discussed.展开更多
Comprehensive studies on CO_(2)breakthrough times and flooding effects are crucial for optimizing CO_(2)flooding strategies.This study utilized numerical simulations to investigate the effects of hydraulic fractures,p...Comprehensive studies on CO_(2)breakthrough times and flooding effects are crucial for optimizing CO_(2)flooding strategies.This study utilized numerical simulations to investigate the effects of hydraulic fractures,permeability,and CO_(2)injection rates on CO_(2)breakthrough times and cumulative oil production.Nonlinear relationships among the respective variables were established,with Sobol method analysis delineating the dominant control factors.The key findings indicate that although hydraulic fracturing shortens CO_(2)breakthrough time,it concurrently enhances cumulative oil production.The orientation of hydraulic fractures emerged as a pivotal factor influencing flooding effectiveness.Furthermore,lower permeability corresponds to lower initial oil production,while higher permeability corresponds to higher initial daily oil production.When reservoir permeability is 1 mD,oil production declines at 1000 days,and at 2 mD,it declines at 700 days.At a surface CO_(2)injection rate of 10,000 m^(3)/d,the daily oil production of a single well is approximately 7.5 m^(3),and this value remains relatively stable over time.The hierarchical order of influence on CO_(2)breakthrough and rapid rise times,from highest to lowest,is permeability,well spacing,CO_(2)injection rate,porosity,and hydraulic fracture conductivity.Similarly,the order of influence on cumulative oil production,from highest to lowest,is well spacing,porosity,permeability,CO_(2)injection rate,and hydraulic fracture conductivity.This paper analyzed the impact of geological and engineering parameters on CO_(2)flooding and oil production and provided insights to optimize CO_(2)injection strategies for enhanced oil recovery.展开更多
Offshore carbon capture, utilization, and storage(OCCUS) is regarded as a crucial technology for mitigating greenhouse gas emissions.Quantitative monitoring maps of sealed carbon dioxide are necessary in a comprehensi...Offshore carbon capture, utilization, and storage(OCCUS) is regarded as a crucial technology for mitigating greenhouse gas emissions.Quantitative monitoring maps of sealed carbon dioxide are necessary in a comprehensive OCCUS project. A potential high-resolution method for the aforementioned purpose lies in the full-waveform inversion(FWI) of time-lapse seismic data. However, practical applications of FWI are severely restricted by the well-known cycle-skipping problem. A new time-lapse FWI method using cross-correlation-based dynamic time warping(CDTW) is proposed to detect changes in the subsurface property due to carbon dioxide(CO_(2)) injection and address the aforementioned issue. The proposed method, namely CDTW, which combines the advantages of cross-correlation and dynamic time warping, is employed in the automatic estimation of the discrepancy between the seismic signals simulated using the baseline/initial model and those acquired. The proposed FWI method can then back-project the estimated discrepancy to the subsurface space domain, thereby facilitating retrieval of the induced subsurface property change by taking the difference between the inverted baseline and monitor models. Numerical results on pairs of signals prove that CDTW can obtain reliable shifts under amplitude modulation and noise contamination conditions. The performance of CDTW substantially outperforms that of the conventional dynamic time warping method. The proposed time-lapse fullwaveform inversion(FWI) method is applied to the Frio-2 CO_(2) storage model. The baseline and monitor models are inverted from the corresponding time-lapse seismic data. The changes in velocity due to CO_(2) injection are reconstructed by the difference between the baseline and the monitor models.展开更多
This project investigated the potential optimal development strategy for a saturated reservoir, with a gas cap. It assessed the viability of three production methods—solution gas drive (primary depletion), water floo...This project investigated the potential optimal development strategy for a saturated reservoir, with a gas cap. It assessed the viability of three production methods—solution gas drive (primary depletion), water flooding and gas injection, using varying injector well numbers. This project also undertook sensitivity analysis in the field, concluding that the development of another appraisal well would vastly improve the accuracy of NPV calculation. Furthermore, this project ascertained an optimized recovery method, based on numerical production simulations and economic modelling, of initial solution gas drive recovery, until reservoir pressure equals the bubble point pressure, at which point three water flooding injectors should be employed, developed at six-month intervals to maximise production while limiting CAPEX and OPEX as much as possible.展开更多
There is widespread, though by no means universal, recognition of the importance of carbon capture and storage （CCS） as a carbon mitigation technology. However, the rate of deployment does not match what is required...There is widespread, though by no means universal, recognition of the importance of carbon capture and storage （CCS） as a carbon mitigation technology. However, the rate of deployment does not match what is required for global temperatures to stay well below 2℃. Although some consider the hurdles to achieving the widespread application of CCS to he almost insurmountable, a more optimistic view is that a great deal is now known about CCS through research, demonstration, and deployment. We know how to do it; we are confident it can be done safely and effectively; we know what it costs; and we know that costs are decreasing and will continue to do so. We also know that the world will need CCS as long as countries, companies, and communities continue to use fossil fuels for energy and industrial processes. What is lacking are the necessary policy drivers, along with a technology-neutral approach to decrease carbon emissions in a cost-effective and timely manner while retaining the undoubted benefits of ready access to reliable and secure electricity and energy-intensive industrial products. In this paper, Australia is used as an example of what has been undertaken in CCS over the past 20 years, particularly in research and demonstration, hut also in international collaboration. Progress in the large-scale deployment of CCS in Australia has been too slow. However, the world＇s largest storage project will soon be operational in Australia as part of the Gorgon liquefied natural gas （LNG） project, and investigations are underway into several large-scale CCS Flagship program opportunities. The organization and progress of the Cooperative Research Centre for Greenhouse Gas Technologies （CO2CRC） Otway Project, which is currently Australia＇s only operational storage project, is discussed in some detail because of its relevance to the commercial deployment of CCS. The point is made that there is scope for building on this Otway activity to investigate more broadly （through the proposed Otway Stage 3 and Deep Earth Energy and Environment Programme （AusDEEP）） the role of the subsurface in carbon reduction. There are challenges ahead if CCS is to he deployed as widely as bodies such as the International Energy Agency （IEA） and the Intergovernmental Panel on Climate Change （IPCC） consider to be necessary. Closer international collaboration in CCS will be essential to meeting that challenge.展开更多
Thermo-mechanical energy storage(TMES)technologies have attracted significant attention due to their potential for grid-scale,long-duration electricity storage,offering advantages such as minimal geographical constrai...Thermo-mechanical energy storage(TMES)technologies have attracted significant attention due to their potential for grid-scale,long-duration electricity storage,offering advantages such as minimal geographical constraints,low environmental impact,and long operational lifespans.A key benefit of TMES systems is their ability to perform energy conversion steps that enable interaction with both thermal energy consumers and prosumers,effectively functioning as combined cooling,heating and power(CCHP)systems.This paper reviews recent progress in various TMES technologies,focusing on compressed-air energy storage(CAES),liquid-air energy storage(LAES),pumped-thermal electricity storage(PTES,also known as Carnot battery),and carbon dioxide energy storage(CES),while exploring their potential applications as extended CCHP systems for trigeneration.Techno-economic analysis indicate that TMES-based CCHP systems can achieve roundtrip(power-to-power)efficiencies ranging from 40%to 130%,overall(trigeneration)energy efficiencies from 70%to 190%,and a levelized cost of energy(with cooling and heating outputs converted into equivalent electricity)between 70 and 200$/MWh.In general,the evolution of TMES-based CCHP systems into smart multi-energy management systems for cities or districts in the future is a highly promising avenue.However,current economic analyses remain incomplete,and further exploration is needed,especially in the area“AI for energy storage,”which is crucial for the widespread adoption of TMES-based CCHP systems.展开更多
Although significant amount of H_(2)S(sour gas)rich natural gas is estimated globally,but not much attention has been given to the application of H_(2)S in the oil recovery process.Recent studies on the use of H_(2)S ...Although significant amount of H_(2)S(sour gas)rich natural gas is estimated globally,but not much attention has been given to the application of H_(2)S in the oil recovery process.Recent studies on the use of H_(2)S in oil recovery processes showed that H_(2)S has the potential of improving the oil recovery,and it can be even more effective than using CO_(2) in some processes.H_(2)S can equally dissolve in the water,react with the reservoir rock to change its surface charge,porosity,and permeability.However,previous in-vestigations on H_(2)S oil recovery attributed the improved oil recoveries to the higher miscibility of H_(2)S in the oil,and the reduction in the oil viscosity.Therefore,there is limited understanding on the H_(2)S-oil-brine-rock geochemical interactions,and how they impact the oil recovery process.This study aims to investigate the interactions between H_(2)S,oil,and carbonate formations,and to assess how the combi-nation of H_(2)S and low salinity water can impact the wettability and porosity of the reservoirs.A triple layer surface complexation model was used to understand the influence of key parameters(e.g.,pressure,brine salinity,and composition)on the H_(2)S-brine-oil-rock interactions.Moreover,the effects of mineral content of the carbonate rock on H_(2)S interactions were studied.Thereafter,the results of the H_(2)S-oil-brine-rock interactions were compared with a study where CO_(2) was used as the injected gas.Results of the study showed that the seawater and its diluted forms yielded identicalζ-potential values of about 3.31 mV at a pH of 3.24.This indicates that at very low pH condition,pH controls the ζ-potential of the oil-brine interface regardless of the brine's ionic strength.The study further demonstrated that the presence of other minerals in the carbonate rock greatly reduced the calcite dissolution.For instance,the calcite dissolution was reduced by 4.5%when anhydrite mineral was present in the carbonate rock.Findings from the simulation also indicated that CO_(2) produced negative ζ-potential values for the car-bonate rocks,and these values were reduced by 18.4%-20% when H_(2)S was used as the gas phase.This implies that the H_(2)S shifted the carbonate rockζ-potentials towards positive.The outcomes of this study can be applied when designing CO_(2) flooding and CO_(2) storage where the gas stream contains H_(2)S gas since H_(2)S greatly influences the dissolution of the carbonate mineral.展开更多
This paper presents a summary review on mass transport of coal seam gas(CSG)in coal associated with the coalbed methane(CBM)and CO_(2) geo-sequestration enhanced CBM(CO_(2)-ECBM)recovery and current research advances ...This paper presents a summary review on mass transport of coal seam gas(CSG)in coal associated with the coalbed methane(CBM)and CO_(2) geo-sequestration enhanced CBM(CO_(2)-ECBM)recovery and current research advances in order to provide general knowledge and fundamental understanding of the CBM/ECBM processes for improved CBM recovery.It will discuss the major aspects of theory and technology for evaluation and development of CBM resources,including the gas storage andflow mechanism in CBM reservoirs in terms of their differences with conventional natural gas reservoirs,and their impact on CBM production behavior.The paper summarizes the evaluation procedure and methodologies used for CBM exploration and exploitation with some recommendations.展开更多
文摘To achieve carbon dioxide(CO_(2))storage through enhanced oil recovery,accurate forecasting of CO_(2) subsurface storage and cumulative oil production is essential.This study develops hybrid predictive models for the determination of CO_(2) storage mass and cumulative oil production in unconventional reservoirs.It does so with two multi-layer perceptron neural networks(MLPNN)and a least-squares support vector machine(LSSVM),hybridized with grey wolf optimization(GWO)and/or particle swarm optimization(PSO).Large,simulated datasets were divided into training(70%)and testing(30%)groups,with normalization applied to both groups.Mahalanobis distance identifies/eliminates outliers in the training subset only.A non-dominated sorting genetic algorithm(NSGA-II)combined with LSSVM selected seven influential features from the nine available input parameters:reservoir depth,porosity,permeability,thickness,bottom-hole pressure,area,CO_(2) injection rate,residual oil saturation to gas flooding,and residual oil saturation to water flooding.Predictive models were developed and tested,with performance evaluated with an overfitting index(OFI),scoring analysis,and partial dependence plots(PDP),during training and independent testing to enhance model focus and effectiveness.The LSSVM-GWO model generated the lowest root mean square error(RMSE)values(0.4052 MMT for CO_(2) storage and 9.7392 MMbbl for cumulative oil production)in the training group.That trained model also exhibited excellent generalization and minimal overfitting when applied to the testing group(RMSE of 0.6224 MMT for CO_(2) storage and 12.5143 MMbbl for cumulative oil production).PDP analysis revealed that the input features“area”and“porosity”had the most influence on the LSSVM-GWO model's pre-diction performance.This paper presents a new hybrid modeling approach that achieves accurate forecasting of CO_(2) subsurface storage and cumulative oil production.It also establishes a new standard for such forecasting,which can lead to the development of more effective and sustainable solutions for oil recovery.
文摘The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the information of formation pressure can be response in the seismic data. Therefore, it is possible to monitor the formation pressure using time-lapse seismic method. Apart from formation pressure, the information of porosity and CO_(2) saturation can be reflected in the seismic data. Here, based on the actual situation of the work area, a rockphysical model is proposed to address the feasibility of time-lapse seismic monitoring during CO_(2) storage in the anisotropic formation. The model takes into account the formation pressure, variety minerals composition, fracture, fluid inhomogeneous distribution, and anisotropy caused by horizontal layering of rock layers(or oriented alignment of minerals). From the proposed rockphysical model and the well-logging, cores and geological data at the target layer, the variation of P-wave and S-wave velocity with formation pressure after CO_(2) injection is calculated. And so are the effects of porosity and CO_(2) saturation. Finally, from anisotropic exact reflection coefficient equation, the reflection coefficients under different formation pressures are calculated. It is proved that the reflection coefficient varies with pressure. Compared with CO_(2) saturation, the pressure has a greater effect on the reflection coefficient. Through the convolution model, the seismic record is calculated. The seismic record shows the difference with different formation pressure. At present, in the marine CO_(2) sequestration monitoring domain, there is no study involving the effect of formation pressure changes on seismic records in seafloor anisotropic formation. This study can provide a basis for the inversion of reservoir parameters in anisotropic seafloor CO_(2) reservoirs.
基金the National Natural Science Foundation of China(Grant No.41274111)the Shenhua Group(Grant No.CSCLC-03-JS-2014-08)the National Department Public Benefit Research Foundation of MLR,China(Grant No.201211063-4-1)
文摘Carbon dioxide(CO2) capture and storage(CCS) is considered widely as one of promising options for CO2emissions reduction,especially for those countries with coal-dominant energy mix like China.Injecting and storing a huge volume of CO2in deep formations are likely to cause a series of geomechanical issues,including ground surface uplift,damage of caprock integrity,and fault reactivation.The Shenhua CCS demonstration project in Ordos Basin,China,is the first and the largest full-chain saline aquifer storage project of CO2in Asia.The injection started in 2010 and ended in 2015.during which totally 0.3 million tonnes(Mt) CO2was injected.The project is unique in which CO2was injected into 18 sandstone formations simultaneously and the overlying coal seams will be mined after the injection stopped in 2015.Hence,intense geomechanical studies and monitoring works have been conducted in recent years,including possible damage resulting from the temperature difference between injected CO2and formations,injection induced stress and deformation change,potential failure mode and safety factor,interaction between coal mining and CO2geological storage,determination of injection pressure limit,and surface monitoring by the interferometric synthetic aperture radar(InSAR) technology.In this paper,we first described the background and its geological conditions of the Shenhua CCS demonstration project.Then,we gave an introduction to the coupled thermo-hydro-mechano-chemical(THMC) processes in CO2geological storage,and mapped the key geomechanical issues into the THMC processes accordingly.Next,we proposed a generalized geomechanical research flowchart for CO2geological storage projects.After that,we addressed and discussed some typical geomechanical issues,including design of injection pressure limit.CO2injection induced near-field damage,and interaction between CO2geological storage and coal mining,in the Shenhua CCS demonstration project.Finally,we concluded some insights to this CCS project.
基金Supported by the China National Science and Technology Major Project(2016ZX05016).
文摘The development history of carbon capture,utilization and storage for enhanced oil recovery(CCUS-EOR)in China is comprehensively reviewed,which consists of three stages:research and exploration,field test and industrial application.The breakthrough understanding of CO_(2) flooding mechanism and field practice in recent years and the corresponding supporting technical achievements of CCUS-EOR project are systematically described.The future development prospects are also pointed out.After nearly 60 years of exploration,the theory of CO_(2) flooding and storage suitable for continental sedimentary reservoirs in China has been innovatively developed.It is suggested that C7–C15 are also important components affecting miscibility of CO_(2) and crude oil.The mechanism of rapid recovery of formation energy by CO_(2) and significant improvement of block productivity and recovery factor has been verified in field tests.The CCUS-EOR reservoir engineering design technology for continental sedimentary reservoir is established.The technology of reservoir engineering parameter design and well spacing optimization has been developed,which focuses on maintaining miscibility to improve oil displacement efficiency and uniform displacement to improve sweep efficiency.The technology of CO_(2) capture,injection and production process,whole-system anticorrosion,storage monitoring and other whole-process supporting technologies have been initially formed.In order to realize the efficient utilization and permanent storage of CO_(2),it is necessary to take the oil reservoir in the oil-water transition zone into consideration,realize the large-scale CO_(2) flooding and storage in the area from single reservoir to the overall structural control system.The oil reservoir in the oil-water transition zone is developed by stable gravity flooding of injecting CO_(2) from structural highs.The research on the storage technology such as the conversion of residual oil and CO_(2) into methane needs to be carried out.
文摘The transition to a non-emitting energy mix for power generation will take decades. This transition will need to be sustainable, e.g.economically affordable. Fossil fuels which are abundant have an important role to play in this respect, provided that Carbon Capture and Storage(CCS) is progressively implemented. CCS is the only way to reduce emissions from energy intensive industries.Thus, the need for upgraded and new CCS research facilities is widely recognised among stakeholders across Europe, as emphasised by the Zero Emissions Platform(ZEP) [1] and the European Energy Research Alliance on CCS(EERA-CCS) [2].The European Carbon Dioxide Capture and Storage Laboratory Infrastructure, ECCSEL, provides funders, operators and researchers with significant benefits by offering access to world-class research facilities that, in many cases, are unlikely for a single nation to support in isolation.This implies creation of synergy and the avoidance of duplication as well as streamlining of funding for research facilities.ECCSEL offers open access to its advanced laboratories for talented scientists and visiting researchers to conduct cutting-edge research.In the planning of ECCSEL, gap analyses were performed and CCS technologies have been reviewed to underpin and envisage the future experimental setup; 1) Making use of readily available facilities, 2) Modifying existing facilities, and 3) Planning and building entirely new advanced facilities.The investments required for the first ten years(2015-2025) are expected to be in the range of €80-120 miilion. These investments show the current level of ambition, as proposed during the preparatory phase(2011-2014).Entering the implementation phase in 2015, 9 European countries signed Letter of Intent(LoI) to join a ECCSEL legal entity: France, United Kingdom, Netherlands, Italy, Spain, Poland, Greece, Norway and Switzerland(active observer). As the EU ERIC-regulation [3] would offer the most suitable legal framework for ECCSEL, the host country, Norway, will apply for establishing ERIC as the ECCSEL Research Infrastructure(RI)legal entity in 2017. Until the ECCSEL ERIC is approved by the European Commission(probably by summer 2017), an interim MoU agreement for the implementation phase of ECCSEL RI has been signed by 13 research institutions and universities representing the 9 countries. A consortium of these partners were granted 3 million EURO from Horizon 2020 to boost implementation of ECCSEL from September 2015 and two years onwards.?2016, Institute of Process Engineering, Chinese Academy of Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).
基金he Australian Research Council for financial support(ARC,DE190100965,FL190100126 and CE230100032).
文摘Continuous accumulation and emission into the atmosphere of anthropogenic carbon dioxide(CO_(2)),a major greenhouse gas,has been recognized as a primary contributor to climate change associated with the global warming and acidification of oceans.This has led to drastic changes in the natural ecosystem,and hence an unhealthy ecological environment for human society.Thus,the effective mitigation of the ever increasing CO_(2)emission has been recognized as the most important global challenge.To achieve zero carbon footprint,novel materials and approaches are required for potentially reducing the CO_(2)release,while our current fossil-fuel-based energy must be replaced by renewable energy free from emissions.In this paper,porous carbons with hierarchical pore structures are promising for CO_(2)adsorption and electrochemical CO_(2)reduction owing to their high specific surface area,excellent catalytic performance,low cost and long-term stability.Since efficient gas-phased(electro)catalysis involves the access of reactants to active sites at the gas-liquid-solid triple phase,the hierarchical porous carbon materials possess multiple advantages for various CO_(2)-related applications with enhanced volumetric and gravimetric activities(e.g.,CO_(2)uptake and current density)for practical operations.Recent studies have demonstrated that porous carbon materials exhibited notable activities as CO_(2)adsorbents and provided facile conducting pathways and mass diffusion channels for efficient electrochemical CO_(2)reduction even under the high current operation conditions.Herein,we summarize recent advances in porous carbon materials for CO_(2)capture,storage,and electrochemical conversion.Prospectives and challenges on the rational design of porous carbon materials for scalable and practical CO_(2)capture and conversion are also discussed.
文摘Research progress is required to be enhanced for those storage technologies which store CO_(2)fast and permanently.However,temporary storage technologies importance cannot be denied to immediately reduce global warming and reduce higher CO_(2)concentration in the atmosphere.Continuous CO_(2)storage facilities,semi-batch and batch pilot plants deemed necessary to build for future survival of the earth planet.Membranes can be used to separate CO_(2)from common flue gases followed by mineral carbonation to convert CO_(2)into stable carbonates.Modifications in cement industry,coal fired power plants,fertilizer industries and other chemical process industries appears essential.
文摘The development and deployment of Carbon dioxide Capture and Storage （CCS） technology is a cornerstone of the Norwegian government＇s climate strategy. A number of projects are currently evaluated/planned along the Norwegian West Coast, one at Tjeldbergodden. COe from this project will be utilized in part for enhanced oil recovery in the Halten oil field, in the Norwegian Sea. We study a potential design of such a system. A combined cycle power plant with a gross power output of 832 MW is combined with CO2 capture plant based on a post-combustion capture using amines as a solvent. The captured CO2 is used for enhanced oil recovery （EOR）. We employ a hybrid life-cycle assessment （LCA） method to assess the environmental impacts of the system. The study focuses on the modifications and operations of the platform during EOR. We allocate the impacts connected to the capture of CO2 to electricity production, and the impacts connected to the transport and storage of CO2 to the oil produced. Our study shows a substantial reduction of the greenhouse gas emissions from power production by 80% to 75 g·（kW·h）^-1. It also indicates a reduction of the emissions associated with oil production per unit oil produced, mostly due to the increased oil production. Reductions are especially significant if the additional power demand due to EOR leads to power supply from the land.
基金funded by Australian Research Council Discovery Project(Grant No.DP110104766)financial support from the China Australia Geological Storage of CO_2 Project(CAGS)Australia-China Young Researchers Exchange Program 2012
文摘The use of sequestered carbon dioxide(CO) as the heat exchange fluid in enhanced geothermal system(EGS) has significant potential to increase their productivity, contribute further to reducing carbon emissions and increase the economic viability of geothermal power generation. Coupled COsequestration and geothermal energy production from hot dry rock(HDR) EGS were first proposed 15 years ago but have yet to be practically implemented. This paper reviews some of the issues in assessing these systems with particular focus on the power generation and COsequestration capacity. The Habanero geothermal field in the Cooper Basin of South Australia is assessed for its potential COstorage capacity if supercritical COis used as the working fluid for heat extraction. The analysis suggests that the major COsequestration mechanisms are the storage in the fracture-stimulation damaged zone followed by diffusion into the pores within the rock matrix. The assessment indicates that 5% of working fluid loss commonly suggested as the storage capacity might be an over-estimate of the long-term COsequestration capacity of EGS in which supercritical COis used as the circulation fluid.
文摘Important first phases in the process of implementing CO2 subsurface and ocean storage projects include selecting of best possible location(s) for CO2 storage, and site selection evaluation. Sites must fulfill a number of criteria that boil down to the following basics: they must be able to accept the desired volume of CO2 at the rate at which it is supplied from the CO2 source(s);they must as well be safe and reliable;and must comply with regulatory and other societal requirements. They also must have at least public acceptance and be based on sound financial analysis. Site geology;hydrogeological, pressure, and geothermal regimes;land features;location, climate, access, etc. can all be refined from these basic criteria. In addition to aiding in site selection, site characterization is essential for other purposes, such as foreseeing the fate and impacts of the injected CO2, and informing subsequent phases of site development, including design, permitting, operation, monitoring, and eventual abandonment. According to data from the IEA, in 2022, emissions from Africa and Asias emerging markets and developing economies, excluding Chinas, increased by 4.2%, which is equivalent to 206 million tonnes of CO2 and were higher than those from developed economies. Coal-fired power generation was responsible for more than half of the rise in emissions that were recorded in the region. The difficulty of achieving sustainable socio-economic progress in the developing countries is entwined with the work of reducing CO2 emissions, which is a demanding project for the economy. Organisations from developing countries, such as Bangladesh, Cameroon, India, and Nigeria, have formed partnerships with organisations in other countries for lessons learned and investment within the climate change arena. The basaltic rocks, coal seams, depleted oil and gas reservoirs, soils, deep saline aquifers, and sedimentary basins that developing countries (Bangladesh, Cameroon, India, and Nigeria etc.) possess all contribute to the individual countrys significant geological sequestration potential. There are limited or no carbon capture and storage or clean development mechanism projects running in these countries at this time. The site selection and characterization procedure are not complete without an estimate of the storage capacity of a storage location. Estimating storage capacity relies on volumetric estimates because a site must accept the planned volume of CO2 during the active injection period. As more and more applications make use of site characterization, so too does the body of written material on the topic. As the science of CO2 storage develops, regulatory requirements are implemented, field experience grows, and the economics of CO2 capture and storage improve, so too will site selection and characterisation change.
基金Supported by Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (2019BT02H594)Sanya Technology Innovation Special Project (2022KJCX08)。
文摘Offshore carbon dioxide(CO_(2)) storage is an effective method for reducing greenhouse gas emissions. However, when using traditional seismic wave methods to monitor the migration of sequestration CO_(2) plumes, the characteristics of wave velocity changes tend to become insignificant beyond a certain limit. In contrast, the controllable source electromagnetic method(CSEM) remains highly sensitive to resistivity changes. By simulating different CO_(2) plume migration conditions, we established the relevant models and calculated the corresponding electric field response characteristic curves, allowing us to analyze the CSEM's ability to monitor CO_(2) plumes. We considered potential scenarios for the migration and diffusion of offshore CO_(2) storage, including various burial depths, vertical extension diffusion, lateral extension diffusion,multiple combinations of lateral intervals, and electric field components. We also obtained differences in resistivity inversion imaging obtained by CSEM to evaluate its feasibility in monitoring and to analyze all the electric field(Ex, Ey, and Ez) response characteristics. CSEM has great potential in monitoring CO_(2) plume migration in offshore saltwater reservoirs due to its high sensitivity and accuracy. Furthermore, changes in electromagnetic field response reflect the transport status of CO_(2) plumes, providing an important basis for monitoring and evaluating CO_(2)transport behavior during storage processes.
基金supported by the National Natural Technology Development,China(Grant Nos.ZYYD2022B11 and 2022ZY0048).
文摘Carbon dioxide energy storage(CES)is an emerging compressed gas energy storage technology which offers high energy storage efficiency,flexibility in location,and low overall costs.This study focuses on a CES system that incorporates a high-temperature graded heat storage structure,utilizing multiple heat exchange working fluids.Unlike traditional CES systems that utilize a single thermal storage at low to medium temperatures,this system significantly optimizes the heat transfer performance of the system,thereby improving its cycle efficiency.Under typical design conditions,the round-trip efficiency of the system is found to be 76.4%,with an output power of 334 kW/(kg·s^(-1))per unit mass flow rate,through mathematical modeling.Performance analysis shows that increasing the total pressure ratio,reducing the heat transfer temperature difference,improving the heat exchanger efficiency,and lowering the ambient temperature can enhance cycle efficiency.Additionally,this paper proposes a universal and theoretical CES thermodynamic intrinsic cycle construction method and performance prediction evaluation method for CES systems,providing a more standardized and accurate approach for optimizing CES system design.
基金finically supported by the National Natural Science Foundation of China(Grant Nos.41272349 and 51322906)Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant No.QYZDB-SSW-DQC029)
文摘This paper focuses on the progress in geomechanical modeling associated with carbon dioxide(CO2)geological storage.The detailed review of some geomechanical aspects,including numerical methods,stress analysis,ground deformation,fault reactivation,induced seismicity and crack propagation,is presented.It is indicated that although all the processes involved are not fully understood,integration of all available data,such as ground survey,geological conditions,microseismicity and ground level deformation,has led to many new insights into the rock mechanical response to CO2injection.The review also shows that in geomechanical modeling,continuum modeling methods are predominant compared with discontinuum methods.It is recommended to develop continuum-discontinuum numerical methods since they are more convenient for geomechanical modeling of CO2geological storage,especially for fracture propagation simulation.The Mohr-Coulomb criterion is widely used in prediction of rock mass mechanical behavior.It would be better to use a criterion considering the effect of the intermediate principal stress on rock mechanical behavior,especially for the stability analysis of deeply seated rock engineering.Some challenges related to geomechanical modeling of CO2geological storage are also discussed.
基金supported by the China Postdoctoral Science Foundation(No.2024M752803)the National Natural Science Foundation of China(No.52179112)+1 种基金the Open Fund of National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,China(No.PLN2023-02)the Open Fund of Key Laboratory of Deep Geothermal Resources,Ministry of Natural Resources of the People's Republic of China(No.KLDGR2024B01).
文摘Comprehensive studies on CO_(2)breakthrough times and flooding effects are crucial for optimizing CO_(2)flooding strategies.This study utilized numerical simulations to investigate the effects of hydraulic fractures,permeability,and CO_(2)injection rates on CO_(2)breakthrough times and cumulative oil production.Nonlinear relationships among the respective variables were established,with Sobol method analysis delineating the dominant control factors.The key findings indicate that although hydraulic fracturing shortens CO_(2)breakthrough time,it concurrently enhances cumulative oil production.The orientation of hydraulic fractures emerged as a pivotal factor influencing flooding effectiveness.Furthermore,lower permeability corresponds to lower initial oil production,while higher permeability corresponds to higher initial daily oil production.When reservoir permeability is 1 mD,oil production declines at 1000 days,and at 2 mD,it declines at 700 days.At a surface CO_(2)injection rate of 10,000 m^(3)/d,the daily oil production of a single well is approximately 7.5 m^(3),and this value remains relatively stable over time.The hierarchical order of influence on CO_(2)breakthrough and rapid rise times,from highest to lowest,is permeability,well spacing,CO_(2)injection rate,porosity,and hydraulic fracture conductivity.Similarly,the order of influence on cumulative oil production,from highest to lowest,is well spacing,porosity,permeability,CO_(2)injection rate,and hydraulic fracture conductivity.This paper analyzed the impact of geological and engineering parameters on CO_(2)flooding and oil production and provided insights to optimize CO_(2)injection strategies for enhanced oil recovery.
文摘Offshore carbon capture, utilization, and storage(OCCUS) is regarded as a crucial technology for mitigating greenhouse gas emissions.Quantitative monitoring maps of sealed carbon dioxide are necessary in a comprehensive OCCUS project. A potential high-resolution method for the aforementioned purpose lies in the full-waveform inversion(FWI) of time-lapse seismic data. However, practical applications of FWI are severely restricted by the well-known cycle-skipping problem. A new time-lapse FWI method using cross-correlation-based dynamic time warping(CDTW) is proposed to detect changes in the subsurface property due to carbon dioxide(CO_(2)) injection and address the aforementioned issue. The proposed method, namely CDTW, which combines the advantages of cross-correlation and dynamic time warping, is employed in the automatic estimation of the discrepancy between the seismic signals simulated using the baseline/initial model and those acquired. The proposed FWI method can then back-project the estimated discrepancy to the subsurface space domain, thereby facilitating retrieval of the induced subsurface property change by taking the difference between the inverted baseline and monitor models. Numerical results on pairs of signals prove that CDTW can obtain reliable shifts under amplitude modulation and noise contamination conditions. The performance of CDTW substantially outperforms that of the conventional dynamic time warping method. The proposed time-lapse fullwaveform inversion(FWI) method is applied to the Frio-2 CO_(2) storage model. The baseline and monitor models are inverted from the corresponding time-lapse seismic data. The changes in velocity due to CO_(2) injection are reconstructed by the difference between the baseline and the monitor models.
文摘This project investigated the potential optimal development strategy for a saturated reservoir, with a gas cap. It assessed the viability of three production methods—solution gas drive (primary depletion), water flooding and gas injection, using varying injector well numbers. This project also undertook sensitivity analysis in the field, concluding that the development of another appraisal well would vastly improve the accuracy of NPV calculation. Furthermore, this project ascertained an optimized recovery method, based on numerical production simulations and economic modelling, of initial solution gas drive recovery, until reservoir pressure equals the bubble point pressure, at which point three water flooding injectors should be employed, developed at six-month intervals to maximise production while limiting CAPEX and OPEX as much as possible.
文摘There is widespread, though by no means universal, recognition of the importance of carbon capture and storage （CCS） as a carbon mitigation technology. However, the rate of deployment does not match what is required for global temperatures to stay well below 2℃. Although some consider the hurdles to achieving the widespread application of CCS to he almost insurmountable, a more optimistic view is that a great deal is now known about CCS through research, demonstration, and deployment. We know how to do it; we are confident it can be done safely and effectively; we know what it costs; and we know that costs are decreasing and will continue to do so. We also know that the world will need CCS as long as countries, companies, and communities continue to use fossil fuels for energy and industrial processes. What is lacking are the necessary policy drivers, along with a technology-neutral approach to decrease carbon emissions in a cost-effective and timely manner while retaining the undoubted benefits of ready access to reliable and secure electricity and energy-intensive industrial products. In this paper, Australia is used as an example of what has been undertaken in CCS over the past 20 years, particularly in research and demonstration, hut also in international collaboration. Progress in the large-scale deployment of CCS in Australia has been too slow. However, the world＇s largest storage project will soon be operational in Australia as part of the Gorgon liquefied natural gas （LNG） project, and investigations are underway into several large-scale CCS Flagship program opportunities. The organization and progress of the Cooperative Research Centre for Greenhouse Gas Technologies （CO2CRC） Otway Project, which is currently Australia＇s only operational storage project, is discussed in some detail because of its relevance to the commercial deployment of CCS. The point is made that there is scope for building on this Otway activity to investigate more broadly （through the proposed Otway Stage 3 and Deep Earth Energy and Environment Programme （AusDEEP）） the role of the subsurface in carbon reduction. There are challenges ahead if CCS is to he deployed as widely as bodies such as the International Energy Agency （IEA） and the Intergovernmental Panel on Climate Change （IPCC） consider to be necessary. Closer international collaboration in CCS will be essential to meeting that challenge.
基金supported by the National Natural Science Foundation of China(Grant No.51906150)the Future Foundation of Energy Science(Grant No.WLNY-MS-2022-010)+1 种基金the Open Fund Project of State Key Laboratory of Clean Energy Utilization(Grant No.ZJUCEU2022022)the UK Engineering and Physical Sciences Research Council(EPSRC)(Grant Nos.EP/Y017471/1,and EP/S032622/1].
文摘Thermo-mechanical energy storage(TMES)technologies have attracted significant attention due to their potential for grid-scale,long-duration electricity storage,offering advantages such as minimal geographical constraints,low environmental impact,and long operational lifespans.A key benefit of TMES systems is their ability to perform energy conversion steps that enable interaction with both thermal energy consumers and prosumers,effectively functioning as combined cooling,heating and power(CCHP)systems.This paper reviews recent progress in various TMES technologies,focusing on compressed-air energy storage(CAES),liquid-air energy storage(LAES),pumped-thermal electricity storage(PTES,also known as Carnot battery),and carbon dioxide energy storage(CES),while exploring their potential applications as extended CCHP systems for trigeneration.Techno-economic analysis indicate that TMES-based CCHP systems can achieve roundtrip(power-to-power)efficiencies ranging from 40%to 130%,overall(trigeneration)energy efficiencies from 70%to 190%,and a levelized cost of energy(with cooling and heating outputs converted into equivalent electricity)between 70 and 200$/MWh.In general,the evolution of TMES-based CCHP systems into smart multi-energy management systems for cities or districts in the future is a highly promising avenue.However,current economic analyses remain incomplete,and further exploration is needed,especially in the area“AI for energy storage,”which is crucial for the widespread adoption of TMES-based CCHP systems.
文摘Although significant amount of H_(2)S(sour gas)rich natural gas is estimated globally,but not much attention has been given to the application of H_(2)S in the oil recovery process.Recent studies on the use of H_(2)S in oil recovery processes showed that H_(2)S has the potential of improving the oil recovery,and it can be even more effective than using CO_(2) in some processes.H_(2)S can equally dissolve in the water,react with the reservoir rock to change its surface charge,porosity,and permeability.However,previous in-vestigations on H_(2)S oil recovery attributed the improved oil recoveries to the higher miscibility of H_(2)S in the oil,and the reduction in the oil viscosity.Therefore,there is limited understanding on the H_(2)S-oil-brine-rock geochemical interactions,and how they impact the oil recovery process.This study aims to investigate the interactions between H_(2)S,oil,and carbonate formations,and to assess how the combi-nation of H_(2)S and low salinity water can impact the wettability and porosity of the reservoirs.A triple layer surface complexation model was used to understand the influence of key parameters(e.g.,pressure,brine salinity,and composition)on the H_(2)S-brine-oil-rock interactions.Moreover,the effects of mineral content of the carbonate rock on H_(2)S interactions were studied.Thereafter,the results of the H_(2)S-oil-brine-rock interactions were compared with a study where CO_(2) was used as the injected gas.Results of the study showed that the seawater and its diluted forms yielded identicalζ-potential values of about 3.31 mV at a pH of 3.24.This indicates that at very low pH condition,pH controls the ζ-potential of the oil-brine interface regardless of the brine's ionic strength.The study further demonstrated that the presence of other minerals in the carbonate rock greatly reduced the calcite dissolution.For instance,the calcite dissolution was reduced by 4.5%when anhydrite mineral was present in the carbonate rock.Findings from the simulation also indicated that CO_(2) produced negative ζ-potential values for the car-bonate rocks,and these values were reduced by 18.4%-20% when H_(2)S was used as the gas phase.This implies that the H_(2)S shifted the carbonate rockζ-potentials towards positive.The outcomes of this study can be applied when designing CO_(2) flooding and CO_(2) storage where the gas stream contains H_(2)S gas since H_(2)S greatly influences the dissolution of the carbonate mineral.
基金supports of Professor Victor Rudolph and Dr Paul Massarotto from School of Chemical Engineering and Professor Sue Golding from School of Earth Science in the University of Queensland.
文摘This paper presents a summary review on mass transport of coal seam gas(CSG)in coal associated with the coalbed methane(CBM)and CO_(2) geo-sequestration enhanced CBM(CO_(2)-ECBM)recovery and current research advances in order to provide general knowledge and fundamental understanding of the CBM/ECBM processes for improved CBM recovery.It will discuss the major aspects of theory and technology for evaluation and development of CBM resources,including the gas storage andflow mechanism in CBM reservoirs in terms of their differences with conventional natural gas reservoirs,and their impact on CBM production behavior.The paper summarizes the evaluation procedure and methodologies used for CBM exploration and exploitation with some recommendations.
