CO2 Capture, Utilization, And Storage Research Articles

Theoretical predictions of CO2, H2 and H2O adsorption mechanisms on M2C-MXene: Selectivity and potential application insights

M2C-MXenes, owing to their abundant adsorption sites, exhibit significant potential in CO2 capture, utilization, and storage (CCUS) and hydrogen energy applications, contributing to hydrogen utilization and global carbon reduction, and thus solving intractable energy and environmental problems. However, the extensive variety of M2C compounds poses challenges to the systematic evaluation of their applications in these fields. The exploration of the adsorption properties of M2Cs is a key fundamental aspect of these studies, and therefore, this study employs calculations across 456 adsorption systems to elucidate the adsorption mechanisms of 19 M2C compounds for small molecules (CO2, H2 and H2O). The results indicate that these M2C materials possess structural stability and metallic characteristics, with periodic variations in the d-band center aligning with trends in CO2 adsorption energy. Notably, molecular orientation impacts adsorption energy more significantly than adsorption sites, particularly for CO2, while M2C compounds primarily exhibit physical adsorption towards H2. Specifically, Sc2C preferentially adsorbs CO2 in atmospheric conditions, and shows chemical adsorption towards H2O, but exhibits negligible adsorption for H2; conversely, Cr2C demonstrates higher adsorption potential for H2. Both materials exhibit favorable thermodynamic stability, suggesting Sc2C is suitable for CCUS applications, while Cr2C holds promising prospects for hydrogen storage.

CO2 storage in saline aquifers: A simulation on quantifying the impact of permeability heterogeneity

As one promising technology to mitigate CO2 emission, CO2 capture utilization and storage (CCUS) plays a crucial role in achieving carbon neutrality. The deep saline aquifer is a prime candidate for CO2 geological storage. The subsurface flow and effectiveness of CO2 storage in deep saline aquifer are highly related to the permeability heterogeneity of formations, which needs in-depth study. To bridge the gap, this study focused on quantifying the impact of permeability heterogeneity on the CO2 flow patterns, the well injectivity and the storage efficiency, which aims to enhance the understanding of CO2 storage characteristics in deep saline aquifers. The heterogeneous saline aquifer model was built by using the Sequential Gaussian Simulation (SGSIM) method. A novel classification template was proposed with the CO2 flow patterns classified as “Dispersive”, “Sweeping”, “Fingering”, and “Channeling” for CO2 storage in deep saline aquifers according to the geostatistical parameters (including dimensionless correlation lengths, first and second spatial moment, and Dykstra-Parsons coefficient). For the well injectivity, the results showed that high injectivity occurred when both horizontal and vertical correlation lengths were high or at a favourable connectivity of permeability in the horizontal and vertical directions. In addition, CO2 storage efficiency is higher when both dimensionless horizontal and vertical correlation lengths are in the range of 0.1–0.2. This is because frequent changes between high and low permeability regions led to frequent mutual displacement of water and CO2, resulting in higher residual trapping and slow CO2 front. Therefore, the dimensionless correlation lengths and breakthrough time should be considered simultaneously to achieve safer trapping and maximize the CO2 storage capacity. The findings of this work provide insights into the subsurface flow of CO2 storage in deep saline aquifers with permeability heterogeneity.

Effects of non-equilibrium phase behavior in nanopores on multi-component transport during CO2 injection into shale oil reservoir

Injecting CO2 into shale oil reservoirs is one of the most effective methods for enhancing oil recovery (EOR) while simultaneously facilitating CO2 capture, utilization, and storage (CCUS). However, it is not always that gas dissolution or condensate evaporation reaches equilibrium instantaneously during the CO2 injection process. In cases where equilibrium is not attained instantaneously, conventional vapor-liquid equilibrium models will have certain limitations in characterizing phase transition hysteresis. These limitations will affect the accuracy of simulating multi-component transport in porous media. In this paper, a robust and generic vapor-liquid non-equilibrium thermodynamic model considering nano-confinement effects (NC) was established by introducing component mass transfer rates proportional to the chemical potential difference. The established model was then used to modify the fully-compositional, projection-based embedded discrete fracture model (pEDFM). Furthermore, C++ hybrid programming and the Graphics Processing Unit (GPU) parallel method were both used to accelerate both the nonlinear and linear solvers. By comparing with results from MATLAB Reservoir Simulation Tools (MRST), Eclipse, and tNavigator, the accuracy and advantages of our solver were demonstrated. The results show that if the underground fluid undergoes a phase transition from a vapor-liquid two-phase state to a single-phase state, non-equilibrium thermodynamic effects need to be considered, and the simulation results show a larger two-phase zone, higher bottom hole pressure, and lower cumulative liquid production. But the nano-confinement effects will weaken the non-equilibrium thermodynamic effects.

Comprehensive analysis of carbon emission reduction technologies (CRTs) in China's coal-fired power sector: A bottom-up approach

Carbon dioxide (CO2) reduction technologies (CRTs) in the coal-fired power sector play an imperative role in the mitigation of environmental challenges and reducing CO2 emissions to help achieve the 2 °C target. However, a compelling necessity persists for a unified framework that can effectively and accurately estimate the costs and potentials associated with CRTs, arising from the diversity of technologies and unit types. Therefore, this study employs a bottom-up approach to analyze the costs and potential of 25 advanced CRTs in the coal-fired power sector, excluding CO2 capture, utilization and storage (CCUS), across 19 types of coal-fired power units. This analysis amalgamates the CO2 reduction supply curve (CRSC) approach with levelized cost of CO2 reduction (LCOC) and a broken-even analysis which could reflect the sector's average carbon reduction cost. The outcomes reveal the following key insights: (1) These technologies collectively harbor a substantial CO2 conservation potential amounting to 925.61 Mt CO2, with a broken-even price of CNY 410.1/tCO2. This reduction could potentially lower 20%–25 % of CO2 emissions in China's power system in 2022, highlighting the crucial role of CRTs in achieving a low-carbon transition and national climate targets; (2)Steam turbine flow path retrofit (T8) not only offers a relatively high CO2 reduction potential (>60 Mt CO2), but also features a low cost (<CNY 150/tCO2) and high profit (>CNY 0.85/MWh). Prioritizing the development of this technology can significantly accelerate the low-carbon transition of coal power; (3) Carbon price have a paramount influence on the cost-effectiveness of CRTs and driving their adoption.

Optimization of CO2 flooding under dual goals of oil recovery and CO2 storage: Numerical case studies of the first-ever CCUS pilot in Changqing oilfield

CCUS (CO2 capture, utilization, and storage) is an important way to reduce carbon emissions and is increasingly applied in the development of hydrocarbon resources. It is crucial to develop proper engineering parameters to achieve the dual goals of enhanced oil recovery (EOR) and CO2 storage. This paper reports systematic numerical case studies of the first-ever CCUS pilot project at Changqing Oilfield to identify further improvement opportunities compared to the current development strategy. The targeted reservoir is located in the Huang 3 (H3) block and is characterized by ultra-low permeability (<1 mD), low oil production (<5 tons/day), and miscible and near-miscible flooding. A three-phase compositional reservoir model is established and a typical well group, consisting of one injector and eight producers, is selected to perform the numerical case studies. We investigate the influence and sensitivity analysis of engineering parameters on oil production and CO2 storage in ultra-low permeability sandstone reservoirs. The results indicate that the well pattern, the timing of switching to water-alternating-gas injection, the gas-water slug size ratio, and the injection rate are controlling factors to achieve favorable performance. The simulation results show that by using optimized engineering parameters, the oil recovery factor of the target reservoir is significantly increased by 25% and the CO2 storage efficiency is increased by 60%. Finally, an optimized development plan is obtained based on the actual conditions of the target reservoir. The reported case studies are supposed to provide insights into the optimal design and operation of CO2 utilization and storage in hydrocarbon reservoirs.

Evaluation of carbon capture technologies in the oil and gas industry using a socio-technical systems perspective-based decision support system under interval type-2 trapezoidal fuzzy set

Concerns in relation to consequences of global warming and climate change have activated worldwide attempts for mitigating the concentration of carbon dioxide (CO2) produced by the industrial sector. Decarbonizing the oil and gas refining (OGR) industries is a challenging problem for policy-makers owing to its potential to prevent economic, environmental, and health risks. In this regard, CO2 capture, utilization, and storage (CCUS) technologies are the most encouraging options to decarbonize. The technologies related to the part of CO2 capture can play a vital role in solving the mentioned problem. Various technologies have been employed for CO2 capture, and choosing the appropriate technology is a complex multi-criteria decision-making (MCDM) issue. This work develops a novel and robust decision support system (DSS). The DSS integrates MCDM techniques of the Delphi and Entropy integration method (DAEIM) and complex proportional assessment of alternatives (COPRAS) method with the interval type-2 trapezoidal fuzzy (IT2TF) environment. The proposed DSS is used to evaluate, prioritize, and choose technologies for CO2 capture. A hybrid criteria system, which involves elements of socio-technical systems perspective has been used for evaluating the candidate technologies. For implementing the DSS of this work, five capture technologies of post-combustion (A_cc1), pre-combustion (A_cc2), oxy-fuel combustion (A_cc3), direct air capture (A_cc4), and indirect air capture (A_cc5) have been chosen for evaluation. The final value of each technology is A_cc1 (0. 2907), A_cc2 (0.2602), A_cc3 (0.1005), A_cc4 (0.2304), and A_cc5 (0.1181) and the preferences of the technologies are A_cc1> A_cc2> A_cc4> A_cc5> A_cc3. The evaluation findings reveal that post-combustion technology with the value of 0.2907 is the most suitable scenario for the capture of CO2 emissions from Iran's OGR systems. The computation results demonstrate that the suggested DSS is feasible and applicable and give reliable and robust findings for acquiring the optimal CO2 capture technology.

Energy, exergy and economic (3E) analysis of a novel integration process based on coal-fired power plant with CO2 capture & storage, CO2 refrigeration, and waste heat recovery

CO2 capture, utilization, and storage (CCUS) are critical technical measures to effectively mitigate the global climate change problem. However, most of the existing research has focused on the capture end and lacks in-depth analysis of subsequent processes such as compression, leading to limitations in the improvement of system economics. Therefore, a novel CCS system for a 300 MW coal-fired power plant was proposed in this paper with two strategies: (1) a CCS system integrating CO2 refrigeration cycle (CFPP-CCS-CRC); and (2) a CCS co-generation plant integrating CO2 refrigeration cycle (CHP-CCS-CRC). The proposed systems’ performance was comparatively evaluated by applying energy, exergy, and economic (3E) analyses. The results demonstrated that at different CO2 capture percentages (13.1 %∼72.9 %), the CHP-CCS-CRC system has improved energy utilization efficiency by 1.2 %∼5.6 % and exergy efficiency by 7.7 %∼25.8 %, compared to the conventional CCUS system (CFPP-CCS). In particular, at a percentage of 13.1 %, the combined energy consumption of the CHP-CCS-CRC system was 0.39 GJ/tCO2, a 79 % reduction compared to 1.87 GJ/tCO2 of the CFPP-CCS system, which resulted in a static payback period of less than 2 years. In general, the newly proposed system features more adequate energy utilization, lower operating costs, and higher economic efficiency.

CCUS in India: bridging the gap between action and ambition

India has committed to reaching net-zero greenhouse gas emissions by 2070. While targets for CO2 capture, utilization and storage (CCUS) technologies are not explicitly set, the Government of India’s agencies and public-sector enterprises have mentioned CCUS approaches conditionally subject to availability of feasible technology and financing. This paper aims to examine the gap between the current status of CCUS in India and the levels of deployment as projected by modeling exercises. It takes a Talanoa dialogue approach to answer the following questions on CCUS perspective in India: where are we right now, where do we need to be, and how do we get there. The current status of CO2 capture in India is at the pilot/demonstration stage, with the chemicals and steel sectors, being the most advanced. Emergence of the methanol economy as a key avenue for CO2 utilization may be seen at a large-scale. Geologic CO2 storage is at an advanced planning stage via enhanced oil recovery, and will likely be targeted over this decade. From the current and planned stage, India would likely need 400–800 Mt-CO2/year by 2050 to meet its share of the 1.5 °C carbon budget. We suggest several priority research directions for technology development across the CCUS value chain.

Kinetics and structure analysis of CO2 mineralization for recycled concrete aggregate (RCA)

CO2 mineralization of solid waste in the construction industry for green concrete production is a promising approach for economically storing CO2 and recycling solid waste. Recent investigations have underscored the significance of CO2 sequestration and the augmentation of RCA performance engendered by the holistic reaction processes. While there is a pronounced interest in the optimization of macroscopic reaction conditions (e.g., temperature, pressure, etc.), the exploration and enhancement of the reaction kinetics stage often remains under explored. This study employed a reaction kinetics model to quantify the reaction rate unveiled two distinct reaction stages within the mineralization reaction. Early evaporation and pore formation established the groundwork for the diffusion mechanism of gas product layers in the middle and later stages, emphasizing the crucial role of water in connecting solid ion leaching and gas dissolution-diffusion in the reaction. The water content of the reaction has an optimal value (4%–6%), smaller particle size correlates with a higher optimal water content. Pre-soaking with a calcium hydroxide (CH) solution or suspension was employed to improve mineralization reaction kinetics, resulting in RCA with improved pore characteristics and strength. The crushing index decreased by 28.8% and 21.8%, the water absorption rate decreased by 11.1% for both coarse and fine RCA, and the cumulative total porosity of fine RCA decreased by 17.6%. This research aims to broaden the applications of waste concrete in the CO2 capture, utilization and storage (CCUS) industry and produce low-cost, extensively processed, and high-strength RCA products while contributing to sustainable CO2 management.

CO2 dynamic mass balance of low permeability reservoir based on “four regions”

AbstractIn order to limit the increase in global average temperature to 1.5°C, it is necessary to reduce carbon dioxide (CO2) emissions by 45% by 2030. CO2 capture, utilization and storage (CCUS) is one of the effective ways to reduce CO2 emissions. Geological storage of CO2 provides a solution with the lowest economic cost and the fastest effect for reducing CO2 emissions. This article proposes a CO2 storage regional division method based on the characteristics of low‐permeability reservoirs in the Yanchang W oilfield in China. The storage space is divided into four regions: gas phase region, two‐phase or near‐miscible region, diffusion region, and oil phase region. As the displacement progresses, the volume of the gas phase region and the two‐phase or near‐miscible region gradually increases; the volume of the diffusion region first increases and then decreases. By calculating the storage capacity of each region separately, the total storage capacity is finally calculated. The impact of different pressures and injection rates on dynamic CO2 storage capacity was evaluated. The results show that pressure and injection rate are positively correlated with total storage capacity. When CO2 miscible conditions are reached, the increase in total storage capacity will significantly decrease. © 2024 Society of Chemical Industry and John Wiley &amp; Sons, Ltd.

CO2 Storage Monitoring via Time-Lapse Full Waveform Inversion with Automatic Differentiation.

In the field of CO2 capture utilization and storage (CCUS), recent advancements in active-source monitoring have significantly enhanced the capabilities of time-lapse acoustical imaging, facilitating continuous capture of detailed physical parameter images from acoustic signals. Central to these advancements is time-lapse full waveform inversion (TLFWI), which is increasingly recognized for its ability to extract high-resolution images from active-source datasets. However, conventional TLFWI methodologies, which are reliant on gradient optimization, face a significant challenge due to the need for complex, explicit formulation of the physical model gradient relative to the misfit function between observed and predicted data over time. Addressing this limitation, our study introduces automatic differentiation (AD) into the TLFWI process, utilizing deep learning frameworks such as PyTorch to automate gradient calculation using the chain rule. This novel approach, AD-TLFWI, not only streamlines the inversion of time-lapse images for CO2 monitoring but also tackles the issue of local minima commonly encountered in deep learning optimizers. The effectiveness of AD-TLFWI was validated using a realistic model from the Frio-II CO2 injection site, where it successfully produced high-resolution images that demonstrate significant changes in velocity due to CO2 injection. This advancement in TLFWI methodology, underpinned by the integration of AD, represents a pivotal development in active-source monitoring systems, enhancing information extraction capabilities and providing potential solutions to complex multiphysics monitoring challenges.

The potential utility of dendritic fibrous nanosilica as an adsorbent and a catalyst in carbon capture, utilization, and storage.

Anthropogenic emissions of greenhouse gases (GHG; e.g., CO2) are regarded as the most critical cause of the current global climate crisis. To combat this issue, a plethora of CO2 capture, utilization, and storage (CCUS) technologies have been proposed and developed based on a number of technical principles (e.g., post-combustion capture, chemical looping, and catalytic conversion). In this light, the potential utility of dendritic fibrous nanosilica (DFNS) materials is recognized for specific CCUS applications (such as adsorptive capture of CO2 and its catalytic conversion into a list of value-added products (e.g., methane, carbon monoxide, and cyclic carbonates)) with the highly tunable properties (e.g., high surface area, pore volume, multifunctional surface, and open pore structure). This review has been organized to offer a comprehensive evaluation of the approaches required for tuning the textural/morphological/surface properties of DFNS (based on multiple synthesis and modification scenarios) toward CCUS applications. It further discusses the effects of such approaches on the properties of DFNS materials in relation to their CCUS performance. This review is thus expected to help develop and implement advanced strategies for DFNS-based CCUS technologies.

CO2-enhanced oil recovery with CO2 utilization and storage: Progress and practical applications in China

CO2 capture, utilization, and storage (CCUS) is a strategic emerging technology that has undergone rapid development in recent years. CO2-Enhanced oil recovery with CO2 utilization and storage (CCUS-EOR) is currently the most practicable large-scale carbon reduction technology and has become a key tool for large-scale applications of CCUS. In the inceptive period, CCUS-EOR was targeted towards flooding, but has since been extensively adopted for industrialization. At present, CCUS-EOR is being developed for synergistic flooding and storage, and is expected to gradually transition to utilization in geological storage for supporting large-scale carbon reduction to achieve the goal of carbon neutrality. The primary mechanisms controlling CCUS-EOR differ for high-permeability, high-water-cut oil reservoirs; low-permeability oil reservoirs; extra-low permeability oil reservoirs; and tight and shale oil reservoirs. Therefore, identifying the main constraints in the CO2 flooding process and formulating effective development strategies are necessary for maximizing both oil recovery and storage. In the geological storage of CO2, attention must be paid to key factors such as the storage capacity, injectivity, and safety. The storage performance can be enhanced through methods such as synergistic CO2-enhanced water recovery and CO2 storage (CCS-EWR), as well as rapid carbon mineralization in basalt. Globally, CCUS projects have undergone rapid growth, with more than 90 % of operational projects led by or involving oil and gas companies. In China, CCUS-EOR is currently in the early stage of industrial application. The first million-ton CCUS project has recently been completed. China has great potential for CCUS-EOR. An advantage of CCUS-EOR is the early adoption to large-scale applications, while CO2 storage in saline aquifers provides a foundation for promoting large-scale development. In the future, multiple CCUS-EOR clusters are expected to be established in the Bohai Bay Basin, Songliao Basin, Ordos Basin, Yangtze River Delta, and Pearl River Delta regions, which will drive high-quality development of CCUS applications in China. ChineseLibrary Classification Number TE341. Document CodeA.

Research Progress on CO2 Capture, Utilization, and Storage (CCUS) Based on Micro-Nano Fluidics Technology

The research and application of CO2 storage and enhanced oil recovery (EOR) have gradually emerged in China. However, the vast unconventional oil and gas resources are stored in reservoir pores ranging from several nanometers to several hundred micrometers in size. Additionally, CO2 geological sequestration involves the migration of fluids in tight caprock and target layers, which directly alters the transport and phase behavior of reservoir fluids at different scales. Micro- and nanoscale fluidics technology, with their advantages of in situ visualization, high temperature and pressure resistance, and rapid response, have become a new technical approach to investigate gas–liquid interactions in confined domains and an effective supplement to traditional core displacement experiments. The research progress of micro–nano fluidics visualization technology in various aspects, such as CO2 capture, utilization, and storage, is summarized in this paper, and the future development trends and research directions of micro–nano fluidics technology in the field of carbon capture, utilization, and storage (CCUS) are predicted.

Levelized Cost Analysis for Blast Furnace CO2 Capture, Utilization, and Storage Retrofit in China’s Blast Furnace–Basic Oxygen Furnace Steel Plants

As the largest carbon emitter in China’s manufacturing sector, the low-carbon transition of the steel industry is urgent. CO2 capture, utilization, and storage (CCUS) technology is one of the effective measures to reduce carbon emissions in steel industry. In this paper, a comprehensive assessment model of source–sink matching-levelized cost in China’s steel industry is constructed to evaluate the potential, economy, and spatial distribution of CCUS retrofits of blast furnaces in the BF-BOF steel industry. The results show that, if no extra incentive policy is included, the levelized cost of carbon dioxide (LCOCD) of 111 steel plants with a 420.07 Mt/a CO2 abatement potential ranges from −134.87 to 142.95 USD/t. The levelized cost of crude steel (LCOS) range of steel plants after the CCUS retrofits of blast furnaces is 341.81 to 541.41 USD/t. The incentives such as carbon market and government subsidies will all contribute to the early deployment of CCUS projects. The CCUS technology could be prioritized for deployment in North China, Northwest China, and East China’s Shandong Province, but more powerful incentives are still needed for current large-scale deployment. The research results can provide references for the early deployment and policy formulation of CCUS in China’s steel industry.

Investment feasibilities of CCUS technology retrofitting China's coal chemical enterprises with different CO2 geological sequestration and utilization approaches

CO2 capture, utilization, and storage (CCUS) technology provides an efficient alternative for decarbonizing the coal chemical industry under China's carbon neutrality goal. However, uncertainties such as geological conditions, technology level, carbon markets, subsidy policies, etc., will greatly affect investor confidence in the CCUS applicability in this industry. This study develops a trinomial tree real options based CCUS investment decision model to explore CCUS investment feasibilities for China's coal chemical enterprises with different CO2 geological sequestration and utilization approaches, i.e., CO2 enhanced oil recovery (CO2-EOR) projects, CO2 enhanced coalbed methane (CO2-ECBM) projects, and deep saline aquifer (DSA) projects. The findings show that 1) CO2-ECBM projects have a larger investment benefit compared to CO2-EOR and DSA projects, with a critical coalbed methane (CBM) price for the immediate investment of 1.3 CNY/m³ under the current technology and carbon price level. 2) CO2-EOR projects are immediately investable at a critical oil price of 200 CNY/BBL; DSA projects require the execution of a delayed option with a critical carbon price of 361.8 CNY/t. 3) Provincial investment benefits vary substantially depending on CO2 transport distance and product revenue, particularly for CO2-ECBM projects in Henan and Guizhou, which have significant investment benefits due to high local CBM prices and short CO2 transport distances.

Investigations on CO2 migration and flow characteristics in sandstone during geological storage based on laboratory injection experiment and CFD simulation

CO2 geological storage in tight sandstone reservoirs is an effective method of CO2 capture, utilization, and storage (CCUS). CO2 migration and flow characteristics in sandstone during geological storage affect the physical and mechanical properties of rocks significantly. In this study, laboratory injection experiments combined with X-ray computed tomography (CT) scanning and scanning electron microscopy (SEM) tests, and computational fluid dynamics (CFD) numerical simulation have been conducted to investigate the effect of geological and engineering parameters on CO2 migration and flow characteristics. The results show that: (1) The injection rate and injection pressure affect the Sc-CO2 migration path. Moreover, the fluid velocity and fluid pressure affect the pressure distribution in pores significantly. Limiting the injection rate and pressure during the CO2 geological storage is beneficial for the stability of the storage. (2) The pressure distribution of the fluid changes with orders of magnitude depending on the injection pressure. However, the overall transient relative pressure is almost consistent and the fluid pressure in the bending section of the bending pores exhibits a linearly decreasing trend. (3) SEM tests provide a connection between laboratory experiments and CFD simulation on microscopic scale. The injection pressure and the acoustic emission (AE) energy have a positive correlation to a certain extent. The Sc-CO2 migration path could be forecasted preliminarily through the fluctuation of the injection pressure-time curves and AE response. The results enrich the theory of CO2 migration and flow characteristics during CO2 geological storage.

Continuous CO2 abatement via integrated carbon capture and conversion over Ni-MgO-Al2O3 dual-functional materials

Massive emission of CO2 is one of the main contributors to global warming, and CO2 capture, utilization and storage (CCUS) was proposed as an indispensable option for carbon reduction. Recently, integrated carbon capture and conversion (ICCC) was regarded as a potential approach to lower the cost of CCUS, and development of efficient dual-functional materials (DFMs) is among the top priority in the area. Herein, Ni-MgO-Al2O3 DFMs were prepared by calcination of Ni-impregnated Mg-Al layered double hydroxide (MgAl-LDH), as such, the pre-loaded Ni species was actively involved in the decomposition of MgAl-LDH, therefore the synergy and balance of the adsorption and catalytic functionalities for ICCC can be promoted in the resulted DFMs. The optimized sample (20NiMgAl(500)) showed excellent ICCC performance. At 300 °C, continuous abatement of CO2 from simulated flue gas (15 vol.%CO2/N2) was achieved with an excellent efficiency of 280 L·h−1·kg−1. Composition analysis of the effluent gas demonstrated that over 97 % CO2 in the feed could be captured, and over 95 % of the captured CO2 was converted to CH4 with ∼ 100 % selectivity. Full retention of the adsorption capacity was observed for 10 adsorption-methanation cycles, and the post-reaction characterization of the DFMs indicated little structure change. This work may pave a way to the practical application of the ICCC technology, and also inspire other integration approaches between CO2 capture and the following mitigation technologies.

Economic and scale prediction of CO2 capture, utilization and storage technologies in China

In response to the lack of global quantitative research on the potential and scale prediction of CO2 capture, utilization and storage (CCUS) in China under the background of carbon peak and carbon neutrality goals, this study predicts the future economic costs of different links of CCUS technologies and the carbon capture needs of different industries in the scenario of fossil energy continuation. Based on the CO2 utilization and storage potential and spatial distribution in China, a cost-scale calculation model for different regions in China in 2060 is constructed to predict the whole-process economic cost and its corresponding scale potential of CCUS. The results show that a local + remote storage mode is preferred, together with a local utilization mode, to meet China's 27×108 t/a CO2 emission reduction demand under the scenario of fossil energy continuation. Specifically, about 5×108 t CO2 emission is reduced by capture utilization, and the whole-process cost is about −1400–200 RMB/t; about 22×108 t CO2 emission is reduced by capture storage, and the whole-process cost is about 200–450 RMB/t. According to the model results, it is recommended to develop the chemical utilization industry based on P2X (Power to X, where X is raw material) technology, construct the CCUS industrial cluster, and explore a multi-party win-win cooperation mode. A scheme of national trunk pipeline network connecting areas connecting intensive emission reduction demand areas and target storage areas is suggested. The emission reduction cost of thermal power based on CCUS is calculated to be 0.16 RMB/(kW·h).

Computed X‐ray Tomography Investigation of Porosity and Permeability of the Liujiagou Formation Sandstone Exposed to CO2‐Saturated Brine

AbstractIn order to improve CO2 capture, utilization and storage (CCUS) to solve carbon emission, sandstone from the Triassic Liujiagou Formation (LF) from the Ordos Basin in China was investigated using permeability tests and computed X‐ray tomography (CT) scanning. The presence of reactive minerals within the geological CO2 sequestration target storage formation can allow reaction with injected CO2, which changes the porosity and permeability of the LF beds, affecting storage effectiveness. To investigate the effect of chemical reactions on the pore structure and permeability of sandstone cores representing the LF CO2 storage, tests were conducted to analyze the changes in porosity and permeability of sandstone cores induced by CO2‐saturated brine at different reaction times (28‐day maximum reaction period). Porosity and permeability of the sandstone increased after reaction with CO2‐saturated brine due to mineral dissolution. The sandstone exhibited an increase in porosity and permeability after 15 days of reaction with CO2‐saturated brine. Moreover, there was an increase in the volume of large pores in the sandstone after the 28‐day period. The pore network of the sandstone was established through CT results, and the porosity calculated based on the obtained pore network was close to that measured in the test, demonstrating the feasibility to use CT to study the evolution of the microstructure of sandstone after long‐time exposure to CO2‐saturated brine.