The long-term security of carbon dioxide geological storage (CGS) depends on pore structure evolution driven by CO2-water-rock interactions. Experiments were conducted under simulated reservoir conditions (36 degrees C, 7.2 MPa) using Ordos Basin sandstone as the reservoir rock and C30 cement as the sealing material. Pore and mineral evolution were characterized by nuclear magnetic resonance (NMR) T 2 spectra and x-ray diffraction (XRD). Sandstone exhibited a staged evolution following a dissolution-expansion -> precipitation-contraction -> dynamic equilibrium pattern: an initial expansion phase, where dissolution of reactive minerals (e.g., albite and illite) increased meso- and macropore volume, with porosity reaching a local maximum at approximately 16 h during the early expansion stage, followed by a contraction phase marked by mineral transformation (e.g., anorthite) and particle migration, leading to a dynamic dissolution-transformation balance. In contrast, cement maintained a stable microstructure dominated by micropores. These results indicate that early dissolution may temporarily enhance permeability and leakage risk, whereas subsequent precipitation promotes pore-throat clogging and structural self-sealing, improving long-term integrity. The study demonstrates that pore evolution is controlled by dissolution-precipitation cycles and that NMR T 2 spectra effectively capture these dynamics, providing an experimental basis for evaluating storage capacity and leakage risk in geological CO2 storage.
The reuse of decommissioned offshore platforms for geological carbon storage offers a cost-effective and technically feasible strategy to reduce greenhouse gas emissions in emerging economies. This study presents a comprehensive techno-economic assessment of offshore carbon capture and storage (CCS) hubs in Brazil, with a focus on the Merluza Field in the Santos Basin. A detailed cost model was developed to quantify capital expenditure (CAPEX), operational expenditure (OPEX), and the levelized cost of storage (LCOS) for scenarios involving infrastructure reutilization. Results indicate that site characterization dominates the cost structure, accounting for up to 76% of CAPEX in reuse scenarios, despite an overall 6% reduction in total capital investment when compared with new offshore construction. Annual OPEX is estimated at $7.79 million, and over a 40-year project lifespan, the net present value of operational costs reaches $104.68 million. The LCOS ranges from $12.72 to $35.54 per ton of CO2 for a 1.39 Mtpa case, making the Brazilian scenario economically competitive when compared to international benchmarks such as Sleipner and Quest. Moreover, potential revenues from carbon credits and avoided emission penalties could substantially offset total project costs. These findings highlight the financial viability of offshore CCS in Brazil and reinforce its potential integration into national decarbonization strategies under the Paris Agreement. 2026 Society of Chemical Industry and John Wiley & Sons, Ltd.
Syngas, a vital feedstock in the chemical industry, consists of hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), and impurities such as hydrogen sulfide (H2S) and ammonia (NH3). Syngas is used in the production of ammonia, methanol, H2, and so forth. The impurities, such as H2S and CO2, are present in the syngas, which causes a decrease in the quality of syngas, and when H2S and CO2 are released into the air, they cause harm to the environment and contribute to global warming. In the research article, the syngas recovery process was modeled using Aspen Plus software and industrially validated. The Peng-Robson thermodynamic property method is used to simulate the process. The Peng-Robinson is used for hydrocarbons. The effect of the change of the number of distillation stages and the reflux ratio is studied to check the recovery of H2S and CO2 gas. The primary objective is to model and simulate the syngas recovery process. The second objective was to perform a parametric analysis of the process to investigate the effects of changing the number of distillation columns and reflux ratio, as well as studying the impacts of CO2 and H2S recovery and heat integration. In this analysis, the process stream of product steam is utilized to decrease the temperature of the feed stream. It reduced the utility cost of the inlet feed stream, resulting in a 0.03% decrease in cost. The third objective was to conduct a cost analysis of the process before the parametric analysis and the heat integration method to analyze the process's profit. This was due to the process recovering 1.06% H2S gas and 0.002% CO2, and calculating the utilities cost of the process. The fourth objective is an exergy analysis of the process in which the overall exergy destruction is 0.42%. The fifth objective was to use the simulation software ALOHA to model the dispersion of H2 gas. In the case, H2 gas is released into the air; it is a hazardous gas, destroying 1.2 mi. The proposed cryogenic approach achieves 85% CO2 removal, 99% H2S removal, and complete NH3 separation. Exergy analysis shows minimal energy losses, highlighting its advantages over solvent-based techniques. The cost estimate further supports the approach's feasibility, indicating lower operating costs. This study offers a comparative assessment of syngas separation methods, with insights into energy efficiency and economic viability.
To mitigate the greenhouse effect, promoting the clean utilization of fossil fuels and advancing carbon capture, utilization, and storage (CCUS) technologies have become critical pathways. Among these approaches, CO2 and CH4 flooding, as key enhanced oil recovery (EOR) techniques, exhibit dual benefits in both emission reduction and production enhancement. In this study, molecular dynamics simulations are employed to systematically investigate the oil displacement behaviors of CO2 and CH4 in porous media reservoirs. Simulations are conducted under two temperature conditions: 300 K (ambient temperature) and 383 K (elevated temperature). The heat and mass transfer characteristics, as well as multiphase interaction mechanisms, are comparatively analyzed under three injection scenarios: CO2 single flooding, CH4 single flooding, and alternating CO2-CH4 injection. The results indicate that CO2 single flooding at 383 K achieves the highest molecular displacement fraction; however, it is accompanied by pronounced gas channeling. In contrast, under ambient temperature conditions (300 K), alternating injection exhibits significant synergistic effects. In particular, the alternating flooding strategy initiated with CO2 injection enhances molecular displacement fractions while effectively suppressing gas channeling compared with single-gas flooding. At elevated temperature, although alternating injection mitigates the risk of gas channeling, the increased gas diffusion coefficient weakens intermolecular interactions, leading to a reduced displacement efficiency relative to single-phase flooding. By establishing a multidimensional analytical framework that integrates temperature distribution, molecular interactions, and reservoir adsorption characteristics, this study elucidates the intrinsic mechanisms governing gas migration under multi-physical field coupling. The findings provide molecular-scale theoretical insights for optimizing gas injection strategies in unconventional oil reservoirs.
CO2 compression and liquefaction are critical process in carbon capture, utilization, and storage (CCUS) systems. However, CO2 streams obtained from capture sources often contain impurities such as N2, O2, and H2O, which significantly alter the thermophysical properties of pure CO2 and pose considerable challenges for system design and operation. In this study, the Peng-Robinson equation of state was employed within the Aspen HYSYS process simulation platform to systematically investigate the effects and mechanisms of these typical impurities on CO2 throughout the processes of compression, liquefaction, and pipeline transportation. The results reveal the quantitative influence of impurities on the thermodynamic properties, pipeline characteristics, and compression performance of CO2. N2 and O2 decrease the critical temperature and increase the critical pressure of the CO2 mixture, whereas H2O exhibits the opposite effect. In terms of thermodynamic properties, the density of CO2 is more sensitive to pressure variation, whereas viscosity and thermal conductivity are more sensitive to impurity concentration. N2 and O2 exhibit similar effects, whereas the influence of H2O on viscosity and thermal conductivity is negligible. During pipeline transportation, the presence of impurities intensifies pressure loss and pressure drop, with H2O exerting the most significant influence, whereas temperature distribution is only slightly affected. In the compression process, N2 and O2 increase the compressibility factor of CO2 and shift the compression path to the right on the pressure-enthalpy (p-H) diagram, leading to a considerable rise in compression energy consumption. The total energy consumption increases with impurity concentration. This study provides a solid theoretical basis and valuable data support for the optimized design, safe operation, and economic performance of industrial processes involving CO2 mixtures containing impurities.
The integrity of wellbore cement needs to be maintained to ensure the effectiveness and stability of geological CO2 storage (GCS). However, the chemical instability of wellbore cement in CO2-rich environments poses a serious risk of CO2 leakage. This vulnerability arises from CO2-induced alteration of cement hydration products, leading to detrimental physicochemical changes in the cement matrix. This study examined the ability of biochar-modified wellbore cement to resist CO2 attack. The cement samples were initially cured in a 1 wt% NaCl solution for 14 days under the conditions of 17 MPa and 62 degrees C, mimicking deep downhole conditions. Afterward, the samples were completely immersed in an autoclave containing CO2-saturated brine solution, which was maintained under the same pressure and temperature conditions. To evaluate the feasibility of using biochar to mitigate CO2 alteration, microstructural and mineral composition changes in wellbore cement samples were characterized both before and after exposure to CO2 using various techniques, including XRF, micro-CT, and SEM-QEMSCAN. The characterization results indicate that adding biochar enhanced CO2 alteration resistance of the cement matrix. With the addition of 2% biochar, the carbonation depth was reduced to 556.1 & micro;m, compared to 594.7 & micro;m in the reference sample after CO2 exposure. In addition, BC-2 sample showed a smaller reduction in compressive strength (16.25% decrease after 28 days of CO2 exposure), indicating less degradation when exposed to CO2 compared to the RF sample (40.49% decrease after 28 days of CO2 exposure). In short, biochar exhibits moderate resistance to CO2 alteration and shows potential for application in wellbore cement systems to inhibit CO2 penetration.
The injection stage of the CO2 storage process presents distinct technical challenges, primarily in managing multiphase flow dynamics. A comprehensive understanding of phase behavior and P-T effects is required to support efficient injection and optimal storage capacity. In this study, to maximize storage capacity, multiphase CO2 injections were simulated in a low-pressure depleted gas reservoir in the Musi Field of South Sumatra. The economic analysis evaluates two business models (storage-as-a-service and carbon-credit storage service), each assessed within three cooperation schemes (gross split, cost recovery, and public-private partnership), using key financial indicators including NPV, IRR, contractor and government take, and the cost of CO2 storage. The simulation results indicate that CO2 storage in depleted gas reservoirs can be optimized through a variable-phase injection approach. Injection begins in the gas phase while the reservoir pressure remains low until it reaches the CO2 bubble point. Subsequently, operators would inject dense-phase CO2 as the reservoir pressure increases. The injection strategy evaluates multiple wellhead pressure settings and identifies a pressure-profile discontinuity characterized by a sudden increase in bottom-hole pressure when the wellbore pressure crosses the CO2 gas-liquid saturation boundary. With this variable-phase injection management scenario, CO2 storage of up to 67.4 million tons can be achieved in 33.4 years. The storage fees for PPP, cost recovery, and gross split schemes are $11.94, $12.58, and $14.32 per ton CO2, respectively. Carbon credit services follow suit with fees of $36.16, $35.82, and $43.39 per ton CO2 under the same schemes.
Accurate characterization of pore-structure parameters in digital rock images is critical for the reliable prediction of subsurface transport processes, including fluid flow in hydrocarbon reservoirs and geological CO2 storage formations. X-ray computed tomography (XCT) enables nondestructive 3D core imaging, but imaging noise degrades reconstruction accuracy and pore network authenticity. Existing research lacks in-depth analysis of denoising methods' correlation with pore parameters. This study evaluates XCT datasets of carbonate cores, using entropy, structural similarity index (SSIM), porosity, and fractal dimension to compare traditional denoising methods via 3D pore network modeling. Findings show denoising methods significantly affect porosity calculations: total and connected porosity peak relative differences reach 30.5% and 40.95%, respectively. Tortuosity and pore coordination number are notably impacted, whereas fractal dimension and equivalent pore radius are less affected. Dual-filter combinations outperform single filters, whereas combinations of three or more filters are not recommended due to excessive smoothing. Although denoising alters parameter values, it preserves the spatial variation trend of core properties, guiding researchers to balance accuracy and efficiency when selecting denoising strategies. This study provides theoretical guidance for scientific denoising algorithm selection in digital core construction, enhancing microscopic reservoir characterization credibility and promoting precise digital core applications in petroleum engineering.
Greenhouse gas emissions significantly contribute to global warming, highlighting the need for effective and sustainable carbon dioxide (CO2) capture technologies. This study introduces a hybrid carbon capture and storage (CCS) prototype that integrates mist-assisted absorption with coconut fiber adsorption as a low-cost and renewable approach. The system was evaluated in terms of CO2 capture efficiency and energy consumption. The prototype consists of four chambers: mist generation units to enhance gas-liquid contact and coconut fiber packing to adsorb residual CO2. Six experimental modes were tested at two gas flow velocities (0.9 and 1.4 m/s). Real-time CO2 monitoring was performed using NDIR MH-Z16 sensors validated against a reference probe meter, with data acquisition through the NI MyRIO platform. Results showed that capture efficiency increased from 14% to 19% in the baseline condition to a maximum of 65.9% in the hybrid configuration combining six mist modules and coconut fiber. Energy consumption analysis revealed that the energy consumption index (ECI) ranged from 72.95 to 79.85 kWh/kg CO2, with the lowest ECI obtained in the hybrid setup, although mist generation contributed significantly to power demand. Despite higher energy use compared with advanced chemical or vacuum swing adsorption systems, the prototype offers advantages in terms of simplicity, operational practicality, and use of renewable local resources. These findings demonstrate the potential of coconut fiber-based hybrid CCS systems as complementary solutions for decentralized and small-scale applications.
CO2 mineralization of alkaline solid wastes enables permanent CO2 sequestration and the production of cementitious materials. However, the inherently low reactivity of these wastes limits their practical application. This study systematically investigates the impact of CO2 mineralization on steel slag's cementitious activity and develops targeted enhancement strategies. By constructing a comprehensive database integrating experimental and literature data, we employed XGBoost-based machine learning to quantitatively evaluate reactivity-limiting factors. Key findings reveal that while CO2 mineralization minimally directly enhances reactivity, it critically improves slag stability and mitigates risks from trace elements. Subsequent thermodynamic and kinetic studies identified mechanochemical milling and aluminate incorporation as effective methods for boosting slag reactivity. To improve slag performance, we recommend optimizing particle size to <= 20 & micro;m, applying magnetic separation to limit iron content to <= 30 wt%, and integrating mechanochemical milling for enhanced activation.
Carbon capture, utilization, and storage (CCUS) is a key technology for enabling the large-scale, low-carbon utilization of fossil fuels. Scientific and rational source-sink matching is an important basis for site selection in CCUS cluster deployment projects. This study focuses on geological formations in North China, such as saline aquifers, coalfields, oil fields, and gas fields. First, it explores methods for assessing the CO2 geological storage potential of each formation type. Second, it discusses CCUS source-sink matching and pipeline network optimization methods based on the saving mileage method and the least-cost path method. Subsequently, it conducts source-sink matching research for CCUS cluster deployment in North China. Finally, it puts forward recommendations for the cluster deployment of CCUS in the region. The research findings indicate that over a 30-year planning horizon, the cumulative CO2 emissions from 16 large coal-fired power plants in North China are nearly 5.0 billion tons. The total geological storage potential for CO2 in the region is 16.0 billion tons, with saline aquifers offering a distinct storage advantage. After pipeline network optimization, saline aquifers, coal seams, and oil fields can store a total of 3.05 billion tons, 1.47 billion tons, and 0.48 billion tons of CO2, respectively. The optimized plan requires a cumulative planned pipeline length of 2399.5 km and a total investment of $299.97 billion. Compared to the initial plan, pipeline length and cumulative investment can be reduced by 39.83% and 13.64%, respectively. By utilizing the cost path analysis tool in ArcGIS, the impacts of factors such as terrain slope, land-use type, road traffic, and population density on the CCUS pipeline network layout can be comprehensively considered. The CCUS cluster deployment in North China can focus on regions such as those south of the Yin Mountains, east of the Taihang Mountains, south of the Yanshan Mountains, and the southern part of the Qinshui Basin. It is essential to fully leverage the advantages of saline aquifers. Demonstration projects should be established on a cluster basis to streamline the overall layout of the CCUS pipeline network. The study identified source-sink matching schemes that can integrate different regions: by connecting CO2 Emission Source No. 10 with No. 3, Storage Sink No. 8 with No. 4, and Storage Sink No. 1 with Emission Source No. 6, the various CCUS cluster deployment areas in North China can be integrated into a unified whole. This study provides theoretical support for the implementation of CCUS cluster deployment and demonstration projects in North China.
Hydrogen is a promising source of energy, given the current context of depletion of fossil fuels and increased emissions of greenhouse gases. The technological route for obtaining this fuel from the dry reforming of biogas has received considerable attention from researchers, as it converts the polluting gases CH4 and CO(2 )into synthesis gas (H-2 and CO). In this work, Ni-Al catalysts derived from hydrotalcite were modified with lithium through different methods and were tested in the biogas dry reforming. Coprecipitation, wet and dry impregnation methods were applied, as well as memory effect reconstruction. N-2 adsorption-desorption, XRD, TPR, CO2-TPD, SEM, and TPO techniques were used for the characterization of the catalysts. For the catalytic tests, a flow rate of 60% CH4 and 40% CO(2 )was used as synthetic biogas. The ramp tests were carried out in the range from 500 to 750 degrees C while the stability tests were carried out at 700 degrees C for 8 h. The results demonstrated that the different Li incorporation methods had a strong effect on the surface, structural and reduction properties of the obtained catalysts. The coprecipitated sample (CP) presented the best performance in the reaction, due to its smaller crystallite size, high basicity and presence of weak, medium and strong basic sites, while the worst results observed for the impregnated samples were attributed to the formation of the LiAlO2 phase in these samples, resulting in materials with low surface area and large crystallite size. The CP sample reached the highest CH4 conversion (54%) after 480 min of reaction and a low carbon formation rate.
Ongoing carbon dioxide (CO2) buildup in the environment aggravates the Earth's planet, leading to climate change and environmental issues. The post-combustion carbon capture via physical adsorption using an adsorbent is an effective treatment for capturing CO2. Aspen Adsorption is an optimistic design tool for gas adsorption in a fixed-bed capture unit. Aspen Adsorption is widely applied for simulating and optimizing fixed-bed adsorption processes, providing an effective platform for designing and evaluating CO2 capture systems. In this study, the adsorption-based fixed-bed capture unit is developed for CO2 capture using Aspen Adsorption. Three different adsorbents are derived from three classes of biomass materials: (i) coconut shell, (ii) rice husk, and (iii) eucalyptus wood. The characteristics of the developed adsorbents are analyzed and studied. The adsorbents' performance is evaluated in the fixed-bed adsorption system to examine CO2 and N2 adsorption efficiencies. A critical parameter on the main operating conditions, surface textural features, and dimensions of the capture unit, namely, (i) adsorption and desorption temperature and pressure, (ii) adsorbent materials' surface textural characteristics and physicochemical properties, and (iii) adsorption column dimensions, is considered for the adsorption study. Overall, 60% CO2 and 40% N2 gas compositions are employed as the inlet gas stream. The adsorbents' adsorption efficiency and parameters are evaluated and discussed. The simulation results indicate a maximum CO2 recovery rate of 68% and a CO2 purity of 97%. Approximately 5.0 GJ/t of CO2 is the energy consumption required for regeneration.
Reliable characterization of mineralogical and textural changes in rock samples is essential for understanding fluid-rock interactions, particularly in experimental studies simulating subsurface conditions. This study presents a reproducible protocol for scanning electron microscopy (SEM) analysis of rock surfaces before and after exposure to CO2 under controlled temperature and pressure conditions. The protocol enables the precise relocation of observation areas, allowing a direct comparison of microstructural features such as mineral dissolution, secondary precipitation and porosity evolution. Combining SEM with digital image analysis and expert petrographic interpretation, the method enhances the repeatability and quantitative rigor of comparative studies. The complete experimental workflow (from sample preparation to post-exposure imaging) is described in detail, emphasizing the importance of spatial referencing and surface preservation. The protocol is demonstrated through a case study involving detrital sandstone samples from the Middle Eocene of the Ebro Basin (Spain), representing potential reservoir rocks. Samples were exposed to supercritical CO2 under controlled conditions (8 MPa, 40 degrees C, 30 days), either dry or in contact with CO2-saturated brine. Results show that brine-mediated CO2 exposure led to selective mineral dissolution, grain detachment and increased porosity, indicating relatively high geochemical reactivity. In contrast, dry CO2 exposure caused minimal alteration, suggesting that fluid presence is critical for chemical interaction. The proposed protocol enables detailed discrete-time surface characterization and provides a robust framework for evaluating rock-CO2 interactions in geological storage settings.
Depleted hydrocarbon reservoirs are well known for their impermeable seal integrity and secure trapping through structural and residual mechanisms. In such systems, wettability plays a critical role in governing fluid distribution, capillary pressure efficiency, and overall gas storage capacity in underground gas storage (UGS). Therefore, it is crucial to study wettability characteristics under realistic reservoir conditions. While mimicking reservoir conditions in the laboratory is a common practice, researchers have traditionally relied heavily on contact angle measurements despite their well-documented limitations, including sensitivity to surface roughness, contamination, and neglect of pore-scale dynamics. In contrast, capillary pressure curves provide more representative and realistic insights for reservoir simulation modeling. In this study, the porous plate method was employed to measure P c-S w relationships to assess wettability alteration in Berea Brown sandstone under depleted reservoir conditions, complemented by surface-level adsorption analyses. Quartz substrates and powdered quartz were treated with low concentrations (0.028 M) of hexanoic, stearic, and lignoceric acids dissolved in toluene, with adsorption characterized using time-of-flight secondary ion mass spectrometry (TOF-SIMS) and Fourier transform infrared (FTIR) spectroscopy. Both techniques confirmed the adsorption of organic acids, with adsorption intensity increasing with alkyl chain length. However, the P c-S w curves of six sandstone core samples (BB1-BB6) revealed no significant shifts after treatment. In addition, residual water saturations remained within experimental uncertainty (49%-62%), indicating that the cores retained their initial water-wet state. These results highlight a critical discrepancy: while contact angle measurements reported in the literature suggest wettability alteration even at minimal organic acid concentrations, capillary pressure analyses demonstrate that such concentrations are insufficient to induce measurable pore-scale wettability changes in low-permeability sandstone. This study emphasizes the importance of capillary pressure curve measurements over contact angle or surface adsorption analyses for realistic evaluation of wettability alteration, providing more reliable insights for assessing CO2 and H2 storage performance in depleted sandstone reservoirs.
As Brazil moves toward implementing its decarbonization commitments, carbon capture and storage (CCS) hubs are emerging as a key pathway for large-scale CO2 abatement in hard-to-abate sectors. This paper presents a multifactorial, data-driven framework to screen and prioritize potential CCS industrial clusters and hubs across Brazilian regions, emphasizing Rio de Janeiro and S & atilde;o Paulo. The method integrates stratified emission density metrics, clustering algorithms (DBSCAN), and geospatial modeling to identify capture hubs, hypothetically eligible offshore storage wells, and transport corridors. Using emission data from the recognized SEEG database and the Campos and Santos basins as reference sinks, the framework mapped seven industrial capture clusters and nineteen storage clusters from a sample set of emitters from five sectors. The results show that S & atilde;o Paulo and Rio de Janeiro jointly account for over 63% of Brazil's emission reduction target for industry and energy, with 22% from Rio and 86% from S & atilde;o Paulo at hub level. The analysis provides a geospatial and quantitative foundation for identifying industrial capture clusters at multiple territorial scales using emission-stratified metrics, selecting macro-structural fields for the formation of offshore storage clusters and analyzing source-to-sink distance charts to assess transportation logistics. The findings contribute to a critical knowledge base to support the future deployment of CCS routes in Brazil and provide a foundation for subsequent feasibility assessments and economic validation.
The development of membranes has evolved over the last years as an effective CO2 separation technology to fight the environmental impact of post-combustion processes. In this regard, the upgrade of conventional polymers has been approached through different strategies to overcome their permeance-selectivity trade-off. Mixed matrix membranes (MMMs) combine the benefits of fillers within a polymeric matrix to increase the CO2 perm-selectivity. More specifically, the coupling of metal-organic frameworks (MOFs) with high CO2 sorption capacity and CO2-selective plasticizers, such as ionic liquids (ILs), has the potential to further improve the mechanical stability of membranes and their performance concerning CO2 transport. In this work, Pebax1657-based membranes combining the MOF ZIF-8 and 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([EMIM][Tf2N]) IL have been optimized in terms of materials loading in a self-standing framework. Then, their transition to a composite material using the spray-coating technique has been addressed with a simple double-step protocol, avoiding the need of an intermediate gutter layer. Composite membranes, as thin-film composite (TFC) membranes, have the appeal of increasing the membrane permeance while maintaining the selectivity of self-standing membranes. Here, it is described the capacity of the spray-coating technique to convert advanced MMMs into TFC-MMMs to further evaluate them in CO2 separation processes.
The ReAct Cement process represents a significant advancement in sustainable cement manufacturing and offers a practical pathway toward low-carbon or near-zero-carbon cement. In this process, reactive calcium oxide (CaO) is utilized during the secondary production stage to facilitate in situ CO2 mineralization, enabling the formation of a high-performance cement product without compromising durability or strength. The system integrates monoethanolamine (MEA)-based post-combustion CO2 capture with advanced heat-transfer exchangers, fuel-efficient rotary kilns, and air-preheating technologies. Together, these units enhance thermal integration, reduce kiln fuel demand, and enable the captured CO2 to be reused directly within clinker formation, thereby closing the carbon cycle within the process itself. The ReAct configuration leverages natural gas and extensive waste-heat recovery from flue gases, reducing overall CO2 emissions from combustion by approximately 30%-35%, whereas the combined effect of CO2 capture and in-process mineralization achieves an additional reduction of around 60%. By converting remaining process emissions into mineralized cementitious phases, the system has the potential to achieve net-zero or near-zero CO2 output from cement production. The approach also yields economic benefits by lowering fuel consumption, improving thermal efficiency, and utilizing resources that would otherwise be lost to the environment. Overall, this research demonstrates a technically feasible and environmentally transformative approach for decarbonizing cement production and contributes meaningfully to global efforts aimed at achieving a net-zero future for the construction materials sector.
China's resource-based industries, critical components of its industrial ecosystem, face significant challenges in reducing environmental burdens, including air pollutants and CO2 emissions. Although drivers of individual emissions are understood, the synergistic influence of socioeconomic factors on simultaneous reductions of multiple emissions is less explored, particularly from a systemic, consumption-based perspective. This study leverages China's multiregional input-output tables, combined with the structural decomposition analysis method, to analyze the contribution of socioeconomic drivers to air pollution reduction and carbon abatement (PRCA) from the consumption perspective in China's resource-based industries. Additionally, it develops a synergistic emission reduction intensity indicator based on the synergy degree to measure the comprehensive strength of PRCA, thereby evaluating the synergistic efficiency and capability of co-drivers. The findings indicate that the production structure exhibited the most significant impact between 2012 and 2017, contributing 1.48 times more to PRCA in 2015-2017 compared to 2012-2015. Energy efficiency promoted positive synergy during 2012-2015 but subsequently shifted toward negative synergistic emission increases. The final consumption structure had the smallest contribution to PRCA from 2012 to 2017, accounting for only 3.09%. These findings underscore the need for policies tailored to each pollutant and emission source, targeted restructuring of industrial linkages, and stronger regional cooperation. By revealing the untapped potential of non-synergistic factors, this study offers actionable insights for integrating air quality and climate strategies in China's industrial policy toolkit.
This study analysed the use of a CCS system on board ships to reduce CO2 emissions, in line with the new maritime regulations issued by the International Maritime Organisation (IMO). To achieve the desired removal rates, two innovative plant configurations were investigated: the first approach uses a traditional reforming reactor (thermally heated steam methane reformer [tSMR]) heated with burners, whereas the second employs an electrified reforming reactor (electrically heated steam methane reformer [eSMR]). The two solutions were compared considering fuel consumption, system footprint, simplicity of implementation, the ratio between liquefied CO2 and removed CO2, and thermal integration, which are crucial parameters for integrating a CCS system on board ships. Simulation results showed that the eSMR system offers significant advantages in terms of footprint, design simplicity and thermal integration. However, the tSMR system exhibits greater efficiency in liquefied CO2 storage and fuel consumption reduction for engines running on HFO with a specific fuel oil consumption (SFOC) of approximately 180 g/kWh. Additionally, it has a smaller footprint at low CO2 removal rates. Consequently, the optimal solution depends on several factors, including the type of vessel (short- or long-range routes), engine characteristics and specific fuel consumption, the type of fuel used and the CO2 reduction target. In conclusion, both solutions demonstrate superior performance compared to traditional systems described in the literature.
