Carbon Capture, Utilization, And Storage Research Articles

A Comprehensive Review of CO2 Mineral Sequestration Methods Using Coal Fly Ash for Carbon Capture, Utilisation, and Storage (CCUS) Technology

CO2 emissions from fossil fuel combustion are the main source of anthropogenic greenhouse gases (GHGs). A method of reducing CO2 emissions is CCUS (carbon capture, utilisation, and storage) technology. One part of CCUS technology involves mineral sequestration as its final stage, utilisation, which can be carried out using natural raw materials or waste. This is a particularly interesting option for power and CHP plants that use coal as their primary fuel. Combustion processes produce fly ash as a waste by-product, which has a high potential for CO2 sequestration. Calcium fly ash from lignite combustion and fly ash from fluidised bed boilers have particularly high potential due to their high CaO content. Fly ash can be used in the mineral sequestration of CO2 via direct and indirect carbonation. Both methods use CO2 and flue gases. Studies conducted so far have analysed the influence of factors such as temperature, pressure, and the liquid-to-solid (L/S) ratio on the carbonation process, which have shown different effects depending on the ash used and the form of the process. Due to the large differences found in the properties of fly ash, related primarily to the type of fuel and boiler used, the process of mineral CO2 sequestration requires much research into its feasibility on an industrial scale. However, the method is promising for industrial applications due to the possibility of reducing CO2 emissions and, at the same time, recovering waste.

Analysis of Technological Pathways and Development Suggestions for Blast Furnace Low-Carbon Ironmaking

Under the global dual-carbon background, heightened public awareness of climate change and strengthened carbon taxation policies are increasing pressure on the steel industry to transition. Given the urgent need for carbon reduction, the exploration of low-carbon pathways in a blast furnace (BF) metallurgy emerges as crucial. Evaluating both asset retention and technological maturity, the development of low-carbon technologies for BFs represents the most direct and effective technical approach. This article introduces global advancements in low-carbon metallurgical technologies for BFs, showcasing international progress encompassing hydrogen enrichment, oxygen enrichment, carbon cycling technologies, biomass utilization, and carbon capture, utilization, and storage (CCUS) technologies. Hydrogen enrichment is identified as the primary technological upgrade currently, although its carbon emission reduction potential is limited to 10% to 30%, insufficient to fundamentally address high carbon emissions from BFs. Therefore, this article innovatively proposes a comprehensive low-carbon metallurgical process concept with the substitution of carbon-neutral biomass fuels at the source stage—intensification of hydrogen enrichment in the process stage—fixation of CCUS at the end stage (SS-IP-FE). This process integrates the cleanliness of biomass, the high-efficiency of hydrogen enrichment, and the thoroughness of carbon fixation through CCUS, synergistically enhancing overall effectiveness. This integrated strategy holds promise for achieving a 50% reduction in carbon emissions from BFs in the long processes. Critical elements of these core technologies are analyzed, assessing their cost-effectiveness and emission reduction potential, underscoring comprehensive low-carbon metallurgy as a pivotal direction for future steel industry development with high technological feasibility and emission reduction efficacy. The article also proposes a series of targeted recommendations, suggesting short-term focus on technological optimization, the medium-term enhancement of technology research and application, and the long-term establishment of a comprehensive low-carbon metallurgical system.

Experimental study on the cyclic mineralization of CO2 enriched phase after absorption by a novel biphasic absorbent composed of DEEA and AEP.

The high energy consumption of Carbon Capture Utilization and Storage(CCUS) promotes the research of integrated absorption and mineralization technology. A novel DEEA/AEP biphasic absorbent is used to absorb [Formula: see text]. After phase separation, only one phase enriched with the absorption product is sent into the mineralization system, then reacts with [Formula: see text] to produce [Formula: see text] at normal temperature and pressure. The effects of temperature, Ca/C and dispersion of the system were investigated, and cyclic utilization experiment was also conducted. The process was characterized and analyzed by Thermal gravimetric analysis (TGA), X-ray diffraction (XRD), and nuclear magnetic resonance (13C NMR). The results showed that at 50 [Formula: see text]C, Ca/C = 1, the extent of mineralization of [Formula: see text]-enriched phase mineralization was 95.73% after ultrasonic treatment for 30 min. During 6 cycles, the volume percentage of [Formula: see text]-enriched phase could be maintained at 52-55%, and the [Formula: see text] load was 11.92mol/L. The results above indicate that the [Formula: see text]-enriched phase mineralization technology after absorption by biphasic absorbent can effectively capture [Formula: see text], realize recycling, and reduce CCUS energy consumption.

Progress in Corrosion Protection Research for Supercritical CO2 Transportation Pipelines

Carbon Capture, Utilization, and Storage (CCUS) technology is an emergent field with the potential for substantial CO2 emissions reduction, enabling low-carbon utilization of fossil fuels. It is widely regarded as a critical technology for combating global climate change and controlling greenhouse gas emissions. According to recent studies, China has identified CCUS as a key emissions reduction technology in climate change response and carbon neutrality objectives. Within this framework, supercritical CO2 (SC-CO2) transport pipelines are an essential means for efficient and safe transportation of CO2. Corrosion protection of pipelines enhances the efficiency and safety of CCUS technology and supports broader implementation and application. This paper reviews the current research on corrosion protection for SC-CO2 transport pipelines, discusses effect factors, compares various corrosion protection strategies, and analyzes the challenges in corrosion protection of SC-CO2 transport pipelines. It concludes with a perspective on future research and development directions in this field. This paper is dedicated to providing new research strategies for pipeline corrosion protection in CCUS technology in the future, and providing technical support for pipeline corrosion protection in CCUS industrial applications.

Surface interaction changes in minerals for underground hydrogen storage: Effects of CO2 cushion gas

Hydrogen (H2) offers a promising solution for the energy transition but storing it on a large scale at the surface poses significant technical and environmental challenges. Underground formations provide a practical alternative for large-scale H2 storage, yet understanding H2 behavior under various subsurface conditions is crucial for optimizing storage capacity and efficiency, which are influenced by rock properties such as wettability. This study addresses the gap in literature regarding the wettability of different minerals when CO2 was injected with H2 as a cushion gas. We examined the wettability of various mineral rocks in realistic subsurface circumstances. A series of wettability measurements were carried out using a captive drop instrument under high-pressure and high-temperature conditions, employing seven different minerals.Our findings reveal that mixed gas contact angles are significantly affected by temperature and pressure, with CO2 playing a crucial role in minimizing hydrogen trapping and enhancing CO2 capture in UHS and Carbon Capture, Utilization, and Storage (CCUS) projects. Higher CO2 mole fractions lead in increased contact angles due to the enhanced density and solubility of the gases, especially in basalt. Increasing the CO2 mole fraction from 25 % to 75 % at a constant pressure of 100 bar and temperature of 60 °C caused the contact angle of basalt with brine to rise from 54° to 86°. Pressure has a more pronounced effect on contact angle changes than temperature. For quartz rock in a 50 % H2 + 50 % CO2 mixture, the contact angle changes by 18° when the temperature increases from 20 °C to 80 °C at a constant pressure of 70 bar in distilled water. In contrast, the contact angle changes by 36° when the pressure increases from 10 bar to 100 bar at a constant temperature of 40 °C.These insights are essential for selecting suitable rock formations for underground gas storage, thereby supporting the advancement of hydrogen storage technologies. Furthermore, utilizing CO2 improves technical performance and environmental sustainability while also supporting international efforts to reduce greenhouse gas emissions. Overall, our results offer insightful information about the planning and operation of underground hydrogen storage systems, emphasizing the potential of CO2 to increase storage effectiveness and support carbon sequestration initiatives.

Molecular Insights into CO2 Diffusion Behavior in Crude Oil

CO2 flooding plays a significant part in enhancing oil recovery and is essential to achieving CCUS (Carbon Capture, Utilization, and Storage). This study aims to understand the fundamental theory of CO2 dissolving and diffusing into crude oil and how these processes vary under reasonable reservoir conditions. In this paper, we primarily use molecular dynamics simulation to construct a multi-component crude oil model with 17 hydrocarbons, which is on the basis of a component analysis of oil samples through laboratory experiments. Then, the CO2 dissolving capacity of the multi-component crude was quantitatively characterized and the impacts of external conditions—including temperature and pressure—on the motion of the CO2 dissolution and diffusion coefficients were systematically investigated. Finally, the swelling behavior of mixed CO2–crude oil was analyzed and the diffusion coefficients were predicted; furthermore, the levels of CO2 impacting the oil’s mobility were analyzed. Results showed that temperature stimulation intensified molecular thermal motion and increased the voids between the alkane molecules, promoting the rapid dissolution and diffusion of CO2. This caused the crude oil to swell and reduced its viscosity, further improving the mobility of the crude oil. As the pressure increased, the voids between the internal and external potential energy of the crude oil models became wider, facilitating the dissolution of CO2. However, when subjected to external compression, the CO2 molecules’ diffusing progress within the oil samples was significantly limited, even diverging to zero, which inhabited the improvement in oil mobility. This study provides some meaningful insights into the effect of CO2 on improving molecular-scale mobility, providing theoretical guidance for subsequent investigations into CO2–crude oil mixtures’ complicated and detailed behavior.

Regional Operation of Electricity-Hythane Integrated Energy System Considering Coupled Energy and Carbon Trading

The deepening implementation of the energy and carbon market imposes trading requirements on multiple regional integrated energy system participants, including power generation plants, industrial users, and carbon capture, utilization, and storage (CCUS) facilities. Their diverse roles in different markets strengthen the interconnections among these subsystems. On the other hand, the operation of CCUS, containing carbon capture (CS), power-to-hydrogen (P2H), and power-to-gas (P2G), results in the coupling of regional carbon reduction costs with the operation of electricity and hythane networks. In this paper, we propose a regional economic dispatching model of an integrated energy system. The markets are organized in a centralized form, and their clearing conditions are considered. CCUS is designed to inject hydrogen or natural gas into hythane networks, operating more flexibly. A generalized Nash game is applied to analyze the multiple trading equilibria of different entities. Simulations are carried out to derive a different market equilibrium regarding network scales, seasonal load shifts, and the ownership of CCUS. Simulation results in a 39-bus/20-node coupled network indicate that the regional average carbon prices fluctuate from ¥1078.82 to ¥1519.03, and the organization of independent CCUS is more preferred under the proposed market structure.

The Why, What, Who, When, and Where of Carbon Capture and Storage in Southern Ontario

This paper reviews the five Ws (Why, What, Who, When, and Where) of carbon capture and storage in southwestern Ontario. This area is home to nearly one quarter of Canada’s population and approximately three-quarters of one million people work in the manufacturing sector. Fifteen of the province’s top 20 CO2 emission point sources are in this area. The industries responsible for these emissions include steel mills, refineries and petrochemical plants, and cement plants. These industries are part of the hard-to-abate sector, in that CO2 is used or generated as an integral part of the industrial process. As such, eliminating or even reducing emissions from these industries is a difficult task. Carbon capture and storage (CCS) projects aim to sequester that gas in sedimentary basins over periods exceeding several thousand years. To this end, deeply buried (> 800 m) porous and permeable rocks (a repository) must be overlain by impermeable rocks that act as a seal, preventing the upward migration of CO2 into the atmosphere. The possibility that injection activities could trigger seismicity is but one of the additional considerations. When operational, CCS projects have a negative carbon footprint and the desirability of developing and using this technology has been established for over 20 years. True CCS projects differ from carbon capture, utilization, and storage (CCUS) projects in that the former are only designed with sequestration in mind. One type of CCUS project involves using CO2 for enhanced oil recovery (EOR) and this technology has been employed for several decades. Cambrian sandstones are the most suitable injection targets for CCS in southwestern Ontario because previous oil and gas drilling has shown the rocks to have the necessary characteristics. They are buried below 800 m, can be tens of metres thick, and have adequate porosity and permeability. However, the Cambrian section is lithologically and stratigraphically heterogeneous and oil, gas, and brine can all be present in the pore space. The extent to which this complexity will affect CO2 injection has not yet been evaluated.

Energy transition in the oil and gas sector: Business models for a sustainable future

The global energy landscape is undergoing a significant transformation as industries shift towards more sustainable practices, driven by environmental regulations, societal pressure, and technological advancements. The oil and gas sector, traditionally dependent on fossil fuels, is at the forefront of this energy transition. This review explores the evolving business models that facilitate the industry's transition to a low-carbon economy, focusing on strategies for achieving sustainability while maintaining profitability. Key approaches include diversifying energy portfolios by investing in renewable energy sources such as wind, solar, and hydrogen, as well as enhancing operational efficiency through digital technologies like artificial intelligence and the Internet of Things (IoT). The transition is also marked by an increased focus on carbon capture, utilization, and storage (CCUS) technologies, which mitigate the environmental impact of traditional oil and gas operations. Business models are being reshaped to incorporate circular economy principles, where waste and emissions are minimized through innovation and resource optimization. Furthermore, partnerships between oil and gas companies and renewable energy firms are emerging as a critical pathway for mutual growth and sustainability. This energy transition also involves rethinking the workforce and reskilling employees for emerging sectors, emphasizing the need for adaptability in business models. Regulatory frameworks play a pivotal role in shaping these models, as policies increasingly favor green investments and low-carbon initiatives. As oil and gas companies diversify their portfolios, they are creating new revenue streams that align with global decarbonization goals while ensuring financial resilience. This study highlights how these innovative business models are setting the foundation for a sustainable future in the oil and gas sector, ensuring that the industry remains relevant in a rapidly changing energy ecosystem. Keywords: Energy Transition, Oil and Gas, Business Models, Sustainability, Renewable Energy, Carbon Capture, Circular Economy, Digital Transformation, Decarbonization, Low-Carbon Economy.

Synthesis of nanoporous carbon from Ulva lactuca activated by eggshell for CO2 capture: a novel approach to waste valorization.

Facing the daunting challenge of climate change, driven by escalating greenhouse gas concentrations, our research introduces an innovative solution for CO2 capture. We explore a novel nanoporous carbon derived from Ulva lactuca, activated with eggshell waste, spotlighting waste valorization in mitigating atmospheric CO2. Through a systematic methodology encompassing variable carbonization temperatures (700-900°C) and nitrogen flow rates (2-4ml/min), complemented by a suite of characterization techniques, we unveil the synthesis of this pioneering adsorbent. Our study not only presents a novel, sustainable pathway for CO2 capture but also demonstrates superior performance, particularly with the NC800-4 sample, achieving a CO2 capture capacity of 1.40mmol/g at 30°C, alongside demonstrating consistent adsorption efficiency over four successive adsorption/desorption cycles. This breakthrough underscores the potential of leveraging waste for environmental remediation, offering a dual solution to waste management and carbon capture, utilization, and storage (CCUS) applications.

CO2 absorption performance of biogas slurry enhanced by biochar as a potential solvent in once-through CO2 chemical absorption process

Carbon capture, utilization, and storage (CCUS), offers a promising avenue for mitigating CO2 emissions, in which the big challenge is the high CO2 capture cost. A novel CCUS technology called once-through CO2 chemical absorption using biogas slurry, could potentially reduce the CO2 capture cost through decreasing the energy consumption greatly during CO2 capture. This technology, however, is constrained by the CO2 absorption capacity of biogas slurry. To enhance the CO2 capture capacity of this innovative technology, we proposed a method to enhance CO2 absorption by integrating biochar into biogas slurry. Results indicated that the CO2 absorption capacity of biogas slurry improved by biochar varied with the type of biochar adopted. Among all the investigated biochar, the wood biochar like sea buckthorn and sand willow exhibited the lowest CO2 capture enhancement, with 0.82±0.19 mmol/g and 0.81±0.30 mmol/g, respectively. Biochar from C4 plants like corn stalks and cobs demonstrated the highest enhancement, with 2.11±0.24 mmol/g and 2.47±0.86 mmol/g, respectively. The enhancement driven by C3 plant biochar like millet stalks and shells was intermediate, with 1.62±0.47 mmol/g and 1.62±0.46 mmol/g, respectively. The primary factor for promoting CO2 absorption in the biochar-based biogas slurry was the increase in pH of biogas slurry. The total pore volume of biochar was the principal material property that enhanced CO2 absorption, followed by the EC and BET surface areas of biochar. Increasing the carbonization temperature of biochar could also enhance the CO2 absorption capacity by biogas slurry. In CO2-rich biochar-based biogas slurry, CO2 primarily existed as HCO3− and carbamate. However, for the influence of the biochar's pore structure, CO2 in the CO2-rich biochar-based biogas slurry was more stable than that in CO2-rich biogas slurry.

ANALYSIS OF THE ECONOMIC PERFORMANCE OF PROJECT ADVANCED OIL RECOVERY WITH CO2 INJECTION (EOR/CCUS-CO2) THROUGH FINANCIAL INDICATORS: BRAZILIAN OVERVIEW

Enhanced Oil Recovery (EOR) is a method associated with Carbon Capture, Utilization, and Storage (CCUS) that consists of injecting CO2 into mature oil fields to store CO2 and enhance production. CO2-EOR projects are costly, requiring technical and economic evaluations to determine their viability. This research analyzes various economic parameters in CO2-EOR projects to develop a comprehensive model for assessing their economic viability in Brazil. The model was tested on projects developed by Silva et al. (2010) and included six scenarios of CO2-EOR in mature reservoirs. The results demonstrate the impact on well completion costs. The scenario with the highest oil production had one additional completion and, for this reason, did not show the best Net Present Value (NPV) result. This work also conducts a sensitivity analysis of parameters and reviews their impacts on NPV. Results indicate a significant impact of barrel price and minimum attractiveness rate on the NPV, while finding that the taxation of excess CO2 was not very significant. Low barrel prices (<$9) proved to be unfeasible with negative NPVs.

CCUS: A Panacea or a Placebo in the fight against climate change?

Carbon Capture, Utilization, and Storage (CCUS) is a crucial technology for achieving carbon neutrality, but it faces significant challenges. Despite substantial investments and policy support, CCUS projects have underperformed due to technical difficulties, high costs, and controversies surrounding the fossil fuel industry's involvement. The effectiveness and feasibility of CCUS in reducing carbon emissions remain uncertain. This viewpoint provides a comprehensive analysis of the current state of CCUS technology, examining its potential to reduce carbon emissions, the challenges hindering its deployment, and the strategies needed to overcome these barriers. We discuss the need for a combinatorial approach to unlock CCUS's full potential, and also emphasize the importance of selecting optimal CO₂ utilization pathways to maximize economic benefits and CO₂ absorption. Although CCUS faces technical, economic, and social barriers, it can still play a valuable role in mitigating emissions from hard-to-abate sectors when supported by comprehensive strategies and collaborative efforts among governments, industries, and research institutions. By addressing these challenges and investing in innovation, CCUS can contribute to achieving carbon neutrality and building a sustainable, low-carbon future.

Interwell channeling and sealing technology in Changqing CCUS block

Abstract In the Changqing Oilfield’s CCUS (Carbon Capture, Utilization, and Storage) project, a novel fracture-based inter-well gas migration sealing technology was developed to address the challenges of reduced production and even shutdown of oil and water wells due to inter-well migration. This was particularly crucial in the context of low fracture pressure-bearing capacity below 40 MPa, the absence of precedents in inter-well gas migration sealing techniques, and the difficulty in accurately estimating the fracture communication volume. The technology is grounded in multi-segment plug water blocking techniques, utilizing geological and well-network data to simulate the gas volume within fractures, thereby determining the precise quantity of plugging agent required. To meet the long-term sealing needs, the technology not only incorporates corrosion-resistant gel in the multi-segment plugs but also integrates water-dispersive cement slurry and CO2 corrosion-resistant cement slurry to enhance the durability of the seal. The injection parameters were optimized based on the pressure-bearing characteristics of the formation to prevent pressure leakage. Field tests indicated that the injection pressure increased by 4 MPa after the application of this technology. Despite the occurrence of gas migration during the plugging process, the close approximation between the designed injection volume of 350 cubic meters and the actual required volume of 326 cubic meters suggests that the technique could achieve its intended effectiveness with further adjustments. This technology provides new insights for handling similar inter-well migration issues in CCUS projects and serves as a reference for other similar endeavors.

Regional CCUS strategies in the context of a fully decarbonized society

Global strategies to combat climate change must be implemented through actions at the local level. The complexity and interconnection of the global challenges are, however, difficult to interpret at the local level. This requires enhanced collaboration and coordination together with a shared understanding of the interconnected nature of our energy systems and the strategies that shape them. Global, international, and national strategies for carbon capture utilization and storage (CCUS) have emerged in recent years as carbon is increasingly outlined as a key element in the future energy system. This emphasizes CCUS strategies as an important part of a transition toward a fully decarbonized society. Therefore, principal strategies for CCUS and the energy system need to be coordinated and translated following a spatiotemporal assessment to enable meaningful actions at the local level. This article applies a regional perspective, in which a regional energy system model seeks to bridge the gap between national and local energy planning. The regional energy system is developed as part of an overarching national scenario for the transition towards a fully decarbonized society. This context provides a national boundary shaped by a global ceiling to provide a meaningful and adequate framework for regional and local development in the future. The overarching national scenario frames the potentials and constraints of the regional energy system and CCUS strategies as part of a global transition while enabling investigations of potential ramifications from changes in national objectives. The analysis in the article uses the North Denmark Region as a case and investigates scenarios in which the region assumes various roles as a contributor to the national transition. The results indicate a need for more interactive and dynamic energy planning and CCUS strategies to comprehend possible impacts from the various roles and changes in the national objectives. This article suggests that spatial and temporal awareness at the regional level of CCUS strategies as part of a future fully decarbonized society is key to creating a meaningful context for local actions today.

Spatio-temporal neural networks for monitoring and prediction of CO[formula omitted] plume migration from measurable field data

Carbon capture, utilization, and storage (CCUS) technologies are crucial for mitigating greenhouse gas emissions. The success of CCUS projects hinges on accurate prediction and monitoring of the CO2 plume migration during and after injection. To address the computational burden of traditional numerical simulation methods, previous studies have successfully used neural networks as proxy models to expedite the prediction of the CO2 plume migration. However, these models rely on uncertain inputs, such as the distribution of heterogeneous permeability and porosity maps, which can lead to erroneous predictions and pose a significant hurdle for their adoption in real-world applications. To address this issue, this study introduces a framework for reconstruction and short-term prediction of CO2 plume migration based solely on field measurements, which can directly provide information on CO2 plumes, thus eliminating the dependency on uncertain geological information as model input. The framework trains a spatio-temporal neural network model using simulated data under various geologic scenarios to capture the plume evolution dynamics without constraining it to specific geological scenarios. Once trained, the model integrates global and local field measurements from multiple sources to reconstruct the CO2 plume and predict its spatio-temporal evolution. The effectiveness of the proposed framework is tested using two case studies: one using a synthetic dataset and another with data generated from a model of a real field in the Southern San Joaquin Basin. The results show that the proposed framework can accurately reconstruct and perform short-term predictions of the CO2 plume migration by integrating various forms of field measurements.

Synergistic effect of carbon molecular sieve and alkali metal nitrate on promoting intermediate-temperature adsorption of CO2 over MgAl-layered double hydroxide

The development of intermediate-temperature adsorbents with high CO2 adsorption capacity is crucial for the tandem integration with CO2 hydrogenation catalyst, aimed at enhancing economy viability and minimizing energy consumption in Carbon capture, utilization and storage (CCUS). Although certain porous carbon materials (PCM) have been employed to enhance CO2 adsorption capability of layered double hydroxide (LDH), there remains an urgent necessity to identify more cost-effective and efficient PCM alternatives. Herein, alkali metal nitrates ((Li0.3Na0.18K0.52)NO3, hereafter referred to as LiNaK) modified layered double hydroxide (LDH)/carbon molecular sieve (CMS) composite (LiNaK-LDH/CMS) as promising adsorbents for CO2 capture was reported. The effects of CMS addition and nitrate loading, the calcination and adsorption temperature, as well as the cycling stability were investigated systematically. The results revealed that the CO2 capture capacity of the LiNaK-modified layered double oxide (LDO)/CMS composite (30 mol%LiNaK-LDO/CMS15%)-incorporating with 15 wt% CMS addition and 30 mol% nitrate loading-achieved a remarkable CO2 adsorption capacity of 1.32 mmol/g at 300 °C due to the synergetic interactions between CMS and nitrate; this represents nearly a sevenfold enhancement compared to initial LDO performance. Moreover, the 30 mol%LiNaK-LDO/CMS15% adsorbent also demonstrated commendable cyclic stability after ten adsorption cycles, retaining over 85 % of its initial adsorption capacity. Based on both obtained adsorption performance and characterization data from the adsorbents, a pre-adsorption enhancing CO2 intermediate-temperature adsorption mechanism over LiNaK-LDH/CMS composite through air calcination processes. This study significantly advances LDH-based adsorbent for future research into CO2 intermediate-temperature adsorption.

CO2 high-pressure miscible flooding and storage technology and its application in Shengli Oilfield, China

There are various issues for CO2 flooding and storage in Shengli Oilfield, which are characterized by low light hydrocarbon content of oil and high miscible pressure, strong reservoir heterogeneity and low sweep efficiency, gas channeling and difficult whole-process control. Through laboratory experiments, technical research and field practice, the theory and technology of CO2 high pressure miscible flooding and storage are established. By increasing the formation pressure to 1.2 times the minimum miscible pressure, the miscibility of the medium-heavy components can be improved, the production percentage of oil in small pores can be increased, the displacing front developed evenly, and the swept volume expanded. Rapid high-pressure miscibility is realized through advanced pressure flooding and energy replenishment, and technologies of cascade water-alternating-gas (WAG), injection and production coupling and multistage chemical plugging are used for dynamic control of flow resistance, so as to obtain the optimum of oil recovery and CO2 storage factor. The research results have been applied to the Gao89-Fan142 in carbon capture, utilization and storage (CCUS) demonstration site, where the daily oil production of the block has increased from 254.6 t to 358.2 t, and the recovery degree is expected to increase by 11.6 percentage points in 15 years, providing theoretical and technical support for the large-scale development of CCUS.

Development of efficient CO2 adsorbents: Synthesis and performance evaluation of dopamine-modified halloysite nanotubes loaded with ZIF-8

Carbon capture, utilization, and storage (CCUS) is a crucial technology for achieving carbon reduction targets. The key to CCUS technology lies in developing and designing efficient and low-cost CO2 capture materials. Metal-organic frameworks (MOFs) have emerged as promising CO2 adsorbents in the field of carbon capture. However, high agglomeration of nanoparticles and high cost have severely hindered the application of MOF-based solid adsorbents. This study employs an in-situ growth method to prepare a novel “corncob-shaped” PHNT@ZIF-8 composite material. During the reaction process, surface modification of halloysite nanotubes (HNT) enhances the interaction between HNT and ZIF-8. The resulting PHNT@ZIF-8 exhibits an enhanced CO2 adsorption capacity of 1.48 mmol/g. Notably, the functionalized PHNT@ZIF-8 as CO2 adsorbents demonstrated significant adsorption properties: a high specific surface area of 409.74 m2/g, good selectivity in simulated flue gas composition of 15%/85% (CO2/N2) (39.1), excellent thermal stability, and superior regenerability. Moreover, PHNT@ZIF-8 adsorbs CO2 primarily through van der Waals forces, which involve low energy and are easily reversible. After eight adsorption–desorption cycles, CO2 capacity retention rate remains as high as 93% (1.37 mmol/g). This work enriches the repertoire of solid CO2 composite adsorbents, providing a novel pathway for enhancing CO2 adsorption performance.

Techno-economic-environmental study of CO2 and aqueous formate solution injection for geologic carbon storage and enhanced oil recovery

As carbon capture, utilization, and storage (CCUS), carbon-dioxide enhanced oil recovery (CO2 EOR) has inherent shortcomings, such as inefficient oil recovery and carbon storage, and low storage security with mobile CO2. This paper presents a techno-economic-environmental analysis of using formate species, a product of CO2 electrochemical reduction, as an alternative carbon carrier for sequestration and EOR in a carbonate oil reservoir in the Gulf of Mexico Basin. CO2 injection, water-alternating-CO2 injection, and aqueous formate solution injection were compared using a compositional reservoir simulation model and an economic calculator. Formate solution injection yielded greater levels of oil recovery and net carbon storage, where the carbon-bearing species resided in the dense aqueous phase without having to rely on petrophysical trapping mechanisms (structural and capillary). The enhanced oil production, net carbon storage, and storage security can be promoted by providing formate-based CCUS with more incentives (e.g., greater tax credit) in comparison to CO2-based CCUS for EOR and the manufacture of chemicals and products. In establishing carbon storage incentive policies and regulations, policymakers should include alternative carbon carriers.