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The article focuses on pairing carbon captured from industrial processes with novel electrochemical reactions, particularly involving pulp and paper waste. Topics include enhancing energy efficiency by 10% compared to traditional methods, utilizing 5-hydroxymethylfurfural (HMF) from biowaste to produce 2,5-furandicarboxylic acid (FDCA) for biodegradable plastics, and developing efficient catalyst systems for industrial-scale carbon dioxide reduction.

The economic feasibility of retrofitting an amine based post-combustion CO 2 capture process to an existing Kraft pulp mill and an existing integrated pulp and board mill has been assessed. This study builds on the technical assessment of the energy performance of the mills when retrofitting a post-combustion CO 2 capture process by Onarheim et al. (2017). Between 75 to 100% of the CO 2 emissions from the pulp and paper industry originate from the combustion of biomass. If the raw material is sourced sustainably, these emissions are categorized as carbon neutral. Applying sustainably managed biomass in the pulp and paper processes and capturing the resulting CO 2 for permanent storage enables the industry to go carbon negative. In this study, the economic impact of retrofitting CO 2 capture from the flue gases of the recovery boiler, the multi-fuel boiler and the lime kiln were assessed. The levelized cost of pulp and the cost of CO 2 avoided were evaluated based on six different scenarios varying the CO 2 tax, incentives for renewable electricity production, with and without recognizing biogenic CO 2 emissions as neutral (exempting CO 2 emissions from tax or not), and rewarding captured and permanently stored CO 2 with negative emissions credit. Results show that the pulp and paper industry has a potential for realizing feasible implementation of large-scale industrial Bio-CCS. For cases where 60–90% of total site CO 2 emissions are captured, the cost of avoided CO 2 amounts to 52–66 €/t for the Kraft pulp mill and 71–89 €/t for the integrated pulp and board mill. The cost of avoided CO 2 , and thus the realization of Bio-CCS in the pulp and paper industry, is strongly dependent on prevailing policy frameworks such as the EU ETS. In order to reach a levelized cost of pulp similar to the reference mill without CO 2 capture, a negative CO 2 emission credit of 60–70 €/t CO 2 for the Kraft pulp mill and 70–80 €/t CO 2 for the integrated pulp and board mill will be required. As long as biogenic CO 2 emissions that are captured and permanently stored are not recognized as negative and rewarded accordingly there is no economic incentive for the owners of pulp and paper mills to implement CCS. The only way to get the pulp and paper industry to implement and deploy Bio-CCS will need the support of the decision-makers in promoting the right policy framework and regulations to encourage the investment such as strong incentives for negative emissions which are bankable during the long term operation of the mills. [ABSTRACT FROM AUTHOR]

The performance of an amine-based post-combustion CO 2 capture and storage (CCS) process in an existing Kraft pulp mill and an existing pulp and board mill was assessed. The pulp and paper industry is an energy-intensive industry, with significant amounts of CO 2 emitted onsite. The majority of this CO 2 originates from the combustion of biomass, which renders it carbon neutral if the biomass used by the industry is grown and harvested in a sustainable manner. If the CO 2 emissions from the pulp and paper industry were to be captured and permanently stored, then this could make the industry a potential carbon sink. In this evaluation, different configurations of capturing CO 2 from the flue gases of the recovery boiler, the multi-fuel boiler and the lime kiln were assessed. For a stand-alone Kraft pulp mill, the excess steam available is sufficient to cover the demand from the CO 2 capture plant. For an integrated pulp and board mill, there is less excess steam available for the CO 2 capture plant and an auxiliary boiler may be required. The retrofit of a post-combustion CO 2 capture plant into an existing pulp mill increases the steam demand by 1–8 GJ/air dried tonne (adt) pulp, depending on the volume of the flue gas treated. This translates to a reduction in the amount of electricity exported to the grid by 0.1–1.0 MWh/adt pulp for a stand-alone Kraft pulp mill, and by 0.1–0.5 MWh/adt pulp for an integrated pulp and board mill. The total potential for negative CO 2 emissions amounts to just under 2.0 Mt CO 2 /a both for the market pulp mill and for the integrated pulp and board mill. [ABSTRACT FROM AUTHOR]

In order to meet the IPCC recommendation for an 80% cut in CO 2 emissions by 2050, industries will be required to drastically reduce their emissions. To meet these targets, technologies such as carbon capture and storage (CCS) must be part of the economic set of decarbonisation options for industry. A systematic review of the literature has been carried out on four of the largest industrial sectors (the iron and steel industry, the cement industry, the petroleum refining industry and the pulp and paper industry) as well as selected high-purity sources of CO 2 from other industries to assess the applicability of different CCS technologies. Costing data have been gathered, and for the cement, iron and steel and refining industries, these data are used in a model to project costs per tonne of CO 2 avoided over the time period extending from first deployment until 2050. A sensitivity analysis was carried out on the model to assess which variables had the greatest impact on the overall cost of wide-scale CCS deployment for future better targeting of cost reduction measures. The factors found to have the greatest overall impact were the initial cost of CCS at the start of deployment and the start date at which large scale deployment is started, whilst a slower initial deployment rate after the start date also leads to significantly increased costs. [ABSTRACT FROM AUTHOR]

Abstract: Carbon capture and storage (CCS) is one of a suite of technology options that might play a significant role in reducing greenhouse gas emissions. However, outside of traditional enhanced oil and gas recovery operations with a well established business model, CCS project deployments are struggling with adoption of a federal or international climate policy driver appearing unlikely for the foreseeable future. As part of a feasibility study for an industrial CCS project at the Boise White Paper mill in Washington State, a business model and CCS system design was developed that provided financial surety for the project developers while recognizing that uncertainty in revenue forecasts for CO2 storage would persist for the foreseeable future. Key to the business model was installation of a new 37MWe biomass-fueled power island at the plant that would replace antiquated boilers and that could still supply the necessary steam to run pulp and paper production operations when capturing CO2 emissions under favorable market conditions for monetizing CO2 storage credits. Under unfavorable market conditions, CO2 capture would be suspended and excess power generated from the plant would reduce external electrical energy purchases required for paper mill operations. The net CO2 reduction for the project versus current operations is 1.0MMT of CO2 per year with the CCS system online, and 139ktons per year with the CCS system offline due to reduced natural gas co-firing. So, both operational modes offered a significant net reduction in CO2 emissions. Based on assumptions regarding electricity and natural gas pricing, and CO2 storage revenue generated through an open market mechanism priced at $15 per metric ton CO2, the payback period for the project capturing 0.5MMT/yr (62% of total CO2 production) was estimated at 6.7 years versus 7.4 years with the CCS system offline. Geologic storage was evaluated in the deep flood basalt formations that dominate the storage capacity in Eastern Washington. Sub-basalt sediments were also examined at the site to provide alternative or supplemental storage capacity in the event that storage in the basalt sequences did not prove technically or economically feasible. [Copyright &y& Elsevier]

• Black liquor gasification was coupled with calcium looping. • Calcium looping for CO 2 capture and H 2 production was compared. • CO 2 capture route (39 €/t) was less expensive than H 2 production route (48.8 €/t). • CO 2 avoided cost was highly dependent on capital cost of black liquor gasification. • Export of H 2 had the lowest CO 2 avoided cost among black liquor gasification cases. Although considered one of the major energy-intensive industries (EIIs), the pulp and paper industry has also the potential for energy production from an industrial waste, black liquor. This study proposes black liquor gasification (BLG) coupled with calcium looping (CaL) as a CO 2 capture route for the pulp and paper industry. BLG with H 2 production (BLG-CaL-H 2), BLG with gas turbine combined cycle (BLG-CaL-GT) or with solid oxide fuel cell (BLG-CaL-SOFC) were considered. The dependence of carbon capture and storage (CCS) cost on the natural gas, limestone, electricity imported and H 2 sale prices aside the expenditures related with BLG-CaL were evaluated. The CCS route, based on CaL retrofitted to the pulp and paper plant, was found to have a lower cost of CO 2 avoided (39.0 €/tCO 2) when compared with BLG-CaL (48.8–57.1 €/tCO 2). Between the BLG-CaL scenarios, BLG-CaL-H 2 presented the lowest cost of CO 2 avoided (48.8 €/tCO 2) but the highest energy penalty. Based on the thermodynamic performance, it was shown that CaL retrofit and BLG-CaL-SOFC presented the best overall performance, turning the electricity importer reference plant into electricity exporter. The economic sensitivity showed that the capital requirement of BLG-CaL has a strong effect on the cost of CO 2 avoided for all alternatives. The H 2 production is also strongly affected by the H 2 sale price while BLG-CaL-SOFC and BLG-CaL-GT are strongly dependent on natural gas price. [ABSTRACT FROM AUTHOR]

Hydrogen Economy and Cyclic Economy are advocated, together with the use of perennial (solar, wind, hydro, geo-power, SWHG) and renewable (biomass) energy sources, for defossilizing anthropic activities and mitigating climate change. Each option has intrinsic limits that prevent a stand-alone success in reaching the target. Humans have recycled goods (metals, water, paper, and now plastics) to a different extent since very long time. Recycling carbon (which is already performed at the industrial level in the form of CO 2 utilization and with recycling paper and plastics) is a key point for the future. The conversion of CO 2 into chemicals and materials is carried out since the late 1800s (Solvay process) and is today performed at scale of 230 Mt/y. It is time to implement on a scale of several Gt/y the conversion of CO 2 into energy products, possibly mimicking Nature which does not use hydrogen. In the short term, a few conditions must be met to make operative on a large scale the production of fuels from recycled-C, namely the availability of low-cost: i. abundant, pure concentrated streams of CO 2 , ii. non-fossil primary energy sources, and iii. non-fossil-hydrogen. The large-scale production of hydrogen by Methane Steam Reforming with CO 2 capture (Blue-H 2) seems to be a realistic and sustainable solution. Green-H 2 could in principle be produced on a large scale through the electrolysis of water powered by perennial primary sources, but hurdles such as the availability of materials for the construction of long-living, robust electrochemical cells (membranes, electrodes) must be abated for a substantial scale-up with respect to existing capacity. The actual political situation makes difficult to rely on external supplies. Supposed that cheap hydrogen will be available, its direct use in energy production can be confronted with the indirect use that implies the hydrogenation of CO 2 into fuels (E-fuels), an almost ready technology. The two strategies have both pros and cons and can be integrated. E-Fuels can also represent an option for storing the energy of intermittent sources. In the medium-long term, the direct co-processing of CO 2 and water via co-electrolysis may avoid the production/transport/ use of hydrogen. In the long term, coprocessing of CO 2 and H 2 O to fuels via photochemical or photoelectrochemical processes can become a strategic technology. • Hydrogen Economy and Cyclic Economy are discussed as an option for defossilizing anthropic activities and mitigating climate change. • In the short term, a few conditions must be met to make operative on a large scale the production of fuels from recycled-C. • In the medium-long term, the direct co-processing of CO 2 and water via co-electrolysis may avoid the production/transport/ use of hydrogen. • In the long term, coprocessing of CO 2 and H 2 O to fuels via photochemical or photoelectrochemical processes can become a strategic technology. [ABSTRACT FROM AUTHOR]

In the field of fuzzy sets, distance measures can effectively quantify the relevant uncertainty. Regarding hesitant fuzzy sets (HFSs), improved hesitant fuzzy distance measures have recently been proposed by fusing classical distance measures with hesitation degrees, and the corresponding information enrichment can be probabilistically advanced to pursue new distance measures of probabilistic hesitant fuzzy sets (PHFSs). Aiming at PHFSs, the improved distance measures of HFSs are simulated and extended in this paper, and thus improved distance measures of PHFSs are proposed; the new PHFSs distances are utilized to construct a new method of probabilistic hesitant fuzzy decision-making, called MEREC-TODIM. Firstly, the new probabilistic hesitant fuzzy Hamming distance and Euclidean distance are directly and parametrically established by incorporating hesitation degrees; accordingly, the improved distance measures exhibit a 2 × 2 system on (non-parameter, parameter) and (Hamming, Euclidean), and their distance property, measure size, parameter monotonicity, and promotion degeneration are investigated and acquired. Furthermore, a modified score function is proposed for MEREC to determine attribute weights, and thus a corresponding decision method with TODIM (i.e., MEREC-TODIM) is established for PHFSs applications on evaluation sorting and optimization selection. Finally, MEREC-TODIM is validated through parameter analyses and decision comparisons, and it is effectively applied to two practical examples: Carbon Capture Utilization Storage and PhD Admission Interviews. Highlights: PHF Hamming and Euclidean distances fusing hesitation degrees provide extensions on HFSs and improvements on PHFSs. An improved score function considering deviation degrees emerges to induce MEREC for attribute weight determination. Improved measures-based TODIM and MEREC constitute MEREC-TODIM decision making with validity and performance. [ABSTRACT FROM AUTHOR]

This paper systematically reviews the current applications of various spatial information technologies in CO2 sequestration monitoring, analyzes the challenges faced by spatial information technologies in CO2 sequestration monitoring, and prospects the development of spatial information technologies in CO2 sequestration monitoring. Currently, the spatial information technologies applied in CO2 sequestration monitoring mainly include five categories: eddy covariance method, remote sensing technology, geographic information system, Internet of Things technology, and global navigation satellite system. These technologies are involved in three aspects: monitoring data acquisition, positioning and data transmission, and data management and decision support. Challenges faced by the spatial information technologies in CO2 sequestration monitoring include: selecting spatial information technologies that match different monitoring purposes, different platforms, and different monitoring sites; establishing effective data storage and computing capabilities to cope with the broad sources and large volumes of monitoring data; and promoting collaborative operations by interacting and validating spatial information technologies with mature monitoring technologies. In the future, it is necessary to establish methods and standards for designing spatial information technology monitoring schemes, develop collaborative application methods for cross-scale monitoring technologies, integrate spatial information technologies with artificial intelligence and high-performance computing technologies, and accelerate the application of spatial information technologies in carbon sequestration projects in China. [ABSTRACT FROM AUTHOR]

Post-combustion capture (PCC) of CO 2 from fossil fuel-fired power station flue gas is one of many technologies that are being developed to reduce anthropogenic greenhouse gas emissions in the medium term. Wet-gas scrubbing using aqueous amines is currently the most mature PCC technology suitable for separating CO 2 from coal-fired power station flue gases. In this study, a series of twelve samples of a degraded 30% (w/w) MEA absorbent were obtained over a six month pilot scale PCC campaign at a brown coal-fired power station in Australia. These samples were used to investigate the accumulation of heat-stable salts, inorganics and minerals. The heat-stable salts concentration increased from 0.80 to 2.29% (w/w, as MEA) and organic acids from the oxidative degradation of MEA were the largest component of heat-stable salts. Acid gases such as SO x and NO x , make-up water, ultra-fine fly-ash and corrosion were all sources of the minerals and inorganics that accumulated in the aqueous MEA absorbent. Corrosion was the single biggest contributor of transition metals and the abrupt change in ratios of Fe, Cr and Mo suggests that the dominant corrosion mechanism may have changed towards the end of the campaign. The rapid accumulation of minerals and inorganics during this PCC campaign highlights the importance of continuing research into the interactions between amine absorbents and inorganic or mineral contaminants. The data presented in this study are an important resource for design of laboratory scale experiments to investigate these physical and chemical interactions between aqueous amines, minerals and inorganics. [ABSTRACT FROM AUTHOR]

During the use of compressed CO 2 storage in saline aquifers, complex geochemical reactions may occur, affecting the petrophysical properties of the reservoir rocks and leading to CO 2 depletion. In this paper, the geochemical reaction mechanism of CCES-SA was studied numerically with the Yingcheng Group in the southeast uplift area of the Songliao Basin as the study area. The hydrogeological parameters of the target study area were used as the initial parameters for the numerical simulation study, and the CO 2 -brine-rock geochemical reaction simulation was carried out using the reaction transport model to study the effects of the 20-year geochemical reaction on the physical properties of reservoir rocks and CO 2 consumption through numerical simulation. The following results were obtained by analyzing the numerical simulation results. The long-term geochemical reactions dissolved chlorite and feldspar minerals, etc., and also precipitated carbonates and clay minerals, etc., which were consistent with the actual results. Besides, the dissolution and precipitation of the above minerals did not affect the porosity and permeability of underground aquifers and did not have adverse consequences for extraction. At the end of 20 years of inter-seasonal energy storage, the percentages of CO 2 captured in gas, aqueous phase and minerals were 27%, 65% and 8%, respectively. During storage, it was recommended to inject CO 2 appropriately during closure to maintain gas phase CO 2 content and pressure. During the production process, the acidified formation fluid came into contact with the inner pipe, increased the risk of wellbore corrosion. When selected materials for wellbore materials, it was recommended to choose corrosion-resistant pipes. What was studied in this paper could provide a theoretical reference for underground energy storage projects involving fluid-rock interactions. [ABSTRACT FROM AUTHOR]

Seagrass ecosystems are pivotal in marine environments, serving as crucial habitats for diverse marine species and contributing significantly to carbon sequestration. Accurate classification of seagrass species from underwater images is imperative for monitoring and preserving these ecosystems. This paper introduces Unsupervised Curriculum Learning (UCL) to seagrass classification using the DeepSeagrass dataset. UCL progressively learns from simpler to more complex examples, enhancing the model's ability to discern seagrass features in a curriculum-driven manner. Experiments employing state-of-the-art deep learning architectures, convolutional neural networks (CNNs), show that UCL achieved overall 90.12 % precision and 89 % recall, which significantly improves classification accuracy and robustness, outperforming some traditional supervised learning approaches like SimCLR, and unsupervised approaches like Zero-shot CLIP. The methodology of UCL involves four main steps: high-dimensional feature extraction, pseudo-label generation through clustering, reliable sample selection, and fine-tuning the model. The iterative UCL framework refines CNN's learning of underwater images, demonstrating superior accuracy, generalization, and adaptability to unseen seagrass and background samples of undersea images. The findings presented in this paper contribute to the advancement of seagrass classification techniques, providing valuable insights into the conservation and management of marine ecosystems. The code and dataset are made publicly available and can be assessed here: https://github.com/nabid69/Unsupervised-Curriculum-Learning—UCL. • Developed an unsupervised deep learning framework (UCL) for classifying seagrass and background in undersea images. • Imporved sample selection operation to balance classes by selecting equal samples from each cluster for fine-tuning. • Integrated clustering with curriculum learning in UCL, enabling unsupervised deep model training using clustering labels. • UCL learns features from seabed image to classify seagrass without manual feature crafting or data labeling. • UCL achieved state-of-the-art unsupervised learning results on the benchmark DeepSeaGrass dataset. [ABSTRACT FROM AUTHOR]

Coal-fired power generation has always been a major energy supply source globally. However, a large amount of CO 2 is emitted with the combustion of coal resources, and fly ash, a by-product of coal combustion, is also accumulated in large quantities. The application of CO 2 mineralization in fly ash can not only reduce CO 2 emission but also effectively manage industrial waste, thereby promoting environmental sustainability. This paper used the mechanical ball milling method to activate fly ash and investigated the effects of ball milling time and speed on the CO 2 sequestration in fly ash. At 30 min ball milling time and 400 r/min ball milling speed, the modified fly ash achieves a good CO 2 sequestration capacity of 81.70 g CO2 /kg FA. Compared with raw fly ash, the CO 2 consumption of treated fly ash is higher at 75.41 mmol/mL. The specific surface area and pore volume of treated fly ash are larger at 1.57 m2/g and 4.33 cm3/kg respectively, which is beneficial for enhancing mass transfer capacity and the carbonation effect. As the ratio of mineralized product/coal increases from 0.5 to 4, the crossing-point temperature increases from 157.20 °C to 165.15 °C. Based on the experimental results, the paper discussed the mechanism of ball milling activation to enhance the carbonation effect of fly ash. This study provides theoretical references for the environmentally friendly utilization of fly ash. [Display omitted] • The CO2 mineralization behavior in fly ash by mechanical activation was studied. • Effects of ball milling time and speed on physicochemical properties in fly ash were analyzed. • The application potential of mineralized product produced by treated fly ash was discussed. [ABSTRACT FROM AUTHOR]

Large-scale decarbonization through carbon capture and storage (CCS) may likely involve many commercial-scale CO 2 storage projects located in proximity. Large volumes of CO 2 injected will elevate reservoir pressures and may lead to rapid convergence of fracture pressure thresholds. This analysis employs numerical modeling to analyze how CO 2 plumes and pressure fronts evolve when CO 2 is injected into a single storage formation from multiple projects located in proximity. This analysis also evaluates the extent to which injection well spacing alleviates pressure buildup in the absence of active pressure management tactics. The simulation approach was based on a single, homogenous saline aquifer in which CO 2 injection occurs under a one-injector baseline case and several multi-well cases where well spacing varies. Analysis results show that the extent of pressure buildup is in the range of tens or a few hundreds of kilometers and contingent upon the defining pressure buildup demarcating the front edge. For the geological setting evaluated in this paper, our analysis suggests that without active basin pressure management strategies, commercial-scale projects would likely need to be sited far apart to avoid pressure interference from one another. Analysis results show the radius of CO 2 plume varies approximately from 2 to 3 km from injection wells (each injecting 1 Mt/year for 30 years) depending on cases and modeling parameters assumed. Given the pressure interference, this paper thus draws attention to the importance of greater coordination among storage operators and regulatory stakeholders. Because this analysis assumes a very specific geologic situation, this exploratory analysis bears further investigations across other geologic situations. • This paper conceptualized a foundational modeling and simulation studies exploring possibilities and strategies of basin scale CO 2 storage. This will provide the first considerations of basin scale CO 2 storage. • Multiple scenarios offer insights of injection designs and operations impact on the reservoir pressure and CO 2 plumes through various injection schemes and strategies. • Pressure interference and associated discussions provide much extensive understanding of basin scale CO 2 storage that can be easily applied to industry and real field by adapting reservoir heterogeneity and operation designing. [ABSTRACT FROM AUTHOR]

In the context of carbon emission reduction in the shipping industry, CCUS technology can modify ships to reduce carbon emissions, providing a new direction for the green development of the shipping industry. Based on this, this paper investigates the technology related to carbon capture on ships, firstly puts forward the applicable requirements of carbon capture technology; and analyses the adaptability of the existing carbon capture solutions to the shipping industry; and discusses the development prospect of carbon capture on ships through the three challenges of space utilisation, safety, and economy; and finally analyses the related policies. After analysis and discussion, this paper concludes that the alcohol-amine method is the most suitable carbon capture solution for ships, but there are challenges in economics and space utilisation. The future research direction lies in optimising the performance of the absorber, improving the energy efficiency of the system and solving the CO 2 storage problem. • It analyzes the current situation of the development of the carbon emission reduction business in the shipping industry, and introduces the application of carbon capture, utilization and storage technology (CCUS) in the shipping industry; • The applicable requirements for carbon capture on ships are proposed with regard to the ship's own characteristics; • Carbon capture process types are described in detail and the feasibility of different processes applied to the shipping industry is analyzed; • Summarises the existing cases of carbon capture on board ships and describes the challenges faced by carbon capture technology on board ships. [ABSTRACT FROM AUTHOR]

• Carbon mineralization in mafic and ultramafic formations offers an attractive CO2 storage option. • Several key technical factors affecting the success, scale, and cost of in-situ carbon mineralization projects are discussed. • Overview of pilot tests, projects, and associated costs is provided. Carbon mineralisation in underground mafic and ultramafic formations, known as in-situ carbon mineralisation, has emerged as an attractive technology for permanent CO 2 storage. Despite its potential, this method has received limited attention compared to conventional CO 2 storage in sedimentary formations. However, increasing interest from countries and companies in utilising this approach to permanently store CO 2 via carbon mineralisation has grown in recent years as part of the wider carbon capture and storage expansion seen globally. This review paper aims to provide an in-depth overview of in-situ carbon mineralisation technology. The paper covers key factors crucial for successful implementation, including water consumption, CO 2 injection rate, risk of CO 2 leakage, injectivity, fracture characterisation, pressure management and induced seismicity, thermal effects, surface area of minerals, groundwater contamination, injection strategy, monitoring of confinement, and reservoir modelling. The paper also discusses pilot tests and projects, highlighting their outcomes. Furthermore, it discusses the costs associated with in-situ carbon mineralisation and provides a case study. The primary objective of this paper is to increase awareness and understanding of this relatively new technology within the carbon capture and storage industry. By shedding light on the benefits and challenges of carbon mineralisation in mafic and ultramafic formations, this review aims to encourage further research, development, and adoption of this promising approach for CO 2 emissions reduction and permanent CO 2 storage. [ABSTRACT FROM AUTHOR]

Geological carbon storage and sequestration (GCS), a key method within carbon capture and sequestration (CCS), is globally recognized as an effective strategy to reduce atmospheric carbon dioxide (CO 2) levels and combat the greenhouse effect. However, discrepancies between projected and actual storage capacities, especially in large-scale CO 2 storage, have raised concerns among stakeholders regarding potential overestimations. This paper reviews the definitions and methods used to estimate storage capacity, highlighting variations and providing a practical guide for predictions while suggesting directions for future research. We discuss numerous analytical and numerical models that account for dynamic constraints such as safety considerations, trapping mechanisms, and reservoir performance, primarily focusing on local scales. These models enhance the accuracy of capacity estimations over conventional static models by quantifying CO 2 storage capacity both spatially and temporally. Additionally, this review underscores the need for sophisticated evaluations of large-scale storage. We introduce two pivotal tools designed for basin-scale capacity estimation and discuss the challenges associated with expanding dynamic capacity assessments to larger scales. In conclusion, the paper explores the burgeoning use of machine learning-based models, advocating for future research efforts to leverage machine learning in developing integrated tools that offer more comprehensive and precise capacity estimations for GCS. • Reviews CO2 storage capacity definitions, noting the discrepancies. • Dynamic capacity: safety, trapping, reservoir performance limits beyond static. • Reviews models, uncertainties and influencing factors for capacity estimation. • Focusing on large-scale storage, introduces two efficient estimation tools. • Addresses needs, challenges and techniques of scaling up dynamic capacity. [ABSTRACT FROM AUTHOR]

Active methods for promoting gas hydrate formation, such as agitation, bubbling, and spraying, can lead to increased energy consumption and safety risks. Conversely, studies exploring chemical additives have been extensively reviewed, revealing that these methods often come with certain adverse effects, including reduced gas selectivity, increased mass transfer resistance and shortened lifespan of chemicals involved. However, these adverse effects could be potentially mitigated by using passive methods, which are promising to improve the safety, viability, scalability and lifespan of hydrate-based carbon capture. In this current review paper, passive methods refer to alterations within gas hydrate systems that stimulate hydrate formation without relying on non-mechanical or non-chemical techniques. These passive approaches encompass nano-confinement, surface treatment, suspended nanoparticles, and distributed hydrate systems. The promotion mechanisms, key features, limitations, and challenges associated with these passive methods are summarised in this paper, which provides guidance for the design of CO 2 hydrate reactors for effective carbon capture. • Four categories of passive methods for enhancing gas hydrate formation were reviewed. • Promotion mechanisms, features, and limitations of each method were summarised. • Overarching design guidance for each passive technology was provided. [ABSTRACT FROM AUTHOR]

Blue carbon, a concept that emerged in the last decade, has received increasing attention in recent years. The development of blue carbon as a nature-based solution is crucial to global climate governance, biodiversity conservation, and restoration of fishery resources. This study utilized CiteSpace visualization software to conduct bibliometric and systematic analyses of 3474 papers retrieved from the Web of Science Core Collection in 2003–2022, depicting a comprehensive framework of international research on blue carbon, exploring hotspots and trends, and proposing future directions and implications for ocean and coastal management. Overall, blue carbon research has experienced the early exploration period (2003–2007) based on scientific concepts, the development period (2008–2015) of research on carbon sequestration mechanisms and functions of different organisms and ecosystems, and the outbreak period (2016–2022) of carbon sink system quantification and management based on model prediction. Co-authorship analysis indicated that blue carbon research collaborates well across intuitions and countries, while collaboration among authors needs to be strengthened. Thematic evolution and hotspot analysis based on cited references and keywords revealed that coastal wetlands, especially mangroves, are a popular research theme, and the functional protection and development of management strategies for coastal ecosystems are major current research hotspots. In addition, it emphasized the need to focus on the protection, restoration and creation of blue carbon ecosystems (BCEs), develop sustainable marine ranching to promote blue carbon trading, explore more potential emerging blue carbon, and strengthen the management of blue carbon from the social level in the future. This paper combines traditional bibliometric review with modern visual analysis software to carry out network metrics, clustering and visualization of the blue carbon thematic literature from multiple perspectives, which reflects its novelty. It provides the latest, in-depth and comprehensive insights into blue carbon research that will serve as valuable reference for relevant scholars, managers and governments. [Display omitted] • Blue carbon field has experienced exploration, development and outbreak periods. • Blue carbon research is well-collaborated across institutions and countries. • Coastal wetlands, especially mangroves, have been a popular central research area. • Protection and management of coastal ecosystems are new hotspots in research. • Propose ocean and coastal management implications for realizing the potential of blue carbon. [ABSTRACT FROM AUTHOR]

Residential green spaces are an integral part of urban green infrastructure and its role in climate change adaptation and mitigation. Various urban typologies and changing planning practices affect the amount and structure of residential greenery, which has a direct impact on climate benefits. While urban green and its climate benefits have received increasing attention, there is still limited knowledge on how changing planning practices and related urban typologies impact residential vegetation and its capacity to deliver climate benefits. This paper aims to address this gap by determining the impact of planning practices on residential vegetation, focussing specifically on climate mitigation and adaptation. With the case study of Helsinki, characterized by a high share of green areas, the paper first examines how construction year and urban density affect the amount and structure of vegetation on residential properties. Second, it estimates the carbon sequestration and summer temperatures in the present-day climate. The paper applies spatial modelling and regression analysis to estimate the impact of construction year on the studied dependent variables, while controlling density via gross floor area of buildings. The study demonstrates that the average amount of residential vegetation, as measured using canopy and vegetation cover, has declined 15 percentage points from the 1970 s to early 2010 s and the canopy to low vegetation ratio has decreased constantly over the periods studied. The decline of the canopy cover in particular has reduced the climate benefits of residential vegetation. The paper highlights the significant impact of gross floor area and planning practices on urban vegetation cover and the climate benefits it provides. It also stresses the importance of ensuring sufficient tree cover and permeable surfaces in cities with progressive climate mitigation agenda throughout the chain of urban planning, construction, and subsequent property management stages. [Display omitted] • Residential areas are a vital but understudied part of urban green infrastructure. • The amount of residential vegetation has diminished since the late 1970 s • The decline in canopy cover has reduced the climate benefits of residential areas. • Density and spatial patterns affect the climate benefits of residential vegetation. • Climate-wise, residential areas require sufficient vegetated and permeable surfaces. [ABSTRACT FROM AUTHOR]

Many nations have pledged to reach carbon neutrality by 2050. Embarking on the decarbonization journey, they posited geological carbon storage (GCS) as a pivotal technology within the carbon capture, utilization, and storage (CCUS) framework. The CCUS chain operates to reduce "hard-to-abate" emissions at key sectors by capturing carbon dioxide (CO 2), reusing it, transporting it, or disposing of it via injection into underground geological formations for permanent storage. Despite the global success of GCS ventures, mainly driven by the oil and gas industry, GCS initiatives are still in their early stages in several developing countries. In Brazil, for instance, a full setup covering precise storage capacity databases, potential CCUS clusters, national regulatory structure, and auxiliary computer-aided engineering is underway. Intended to push the frontier in the latter subject, this paper introduces mathematical models for qualifying underground CO 2 storage sites. Our research explores a family of multivariate functionals endowed with underlying reservoir features and distinct weighting functions, thus envisioning two primary objectives. Firstly, it clarifies non-linear interactions between rock and fluid properties using quality indicators. Secondly, it evaluates geographical regions considering structural traps/caprocks settings. Backed by the Matlab Reservoir Simulation Toolbox (MRST) capabilities, the methodology is a subsidiary resource for identifying suitable injection and storage sites. A case study using the UNISIM-I-D model generated dozens of volumetric quality maps that point to unique potential storage sites. Numerical simulation experiments of injection comparing legacy and novel wells reveal storage surpluses improved by up to 50%. The paper seeks to establish foundational knowledge in GCS efficiency for general underground settings. One expects that these outcomes leverage well-repurposing perspectives and stimulate field appraisal actions to scale up GCS projects both in Brazil and worldwide. • Introduction of a family of mathematical functionals for site qualification. • Trap analysis and supercritical gas injection over a Brazilian offshore reservoir model. • Comparison of storage surplus in theoretically-proposed and legacy well locations. [ABSTRACT FROM AUTHOR]

• The government's clean electricity subsidy and carbon utilization subsidy have pushed the timing of CCS retrofitting significantly forward, but the initial investment subsidy has little impact on it. • Under the cooperation mode of coal-fired power plants and oilfield enterprises, the optimal cost-sharing ratio of the initial investment for coal-fired power plants is about 0.4 to promote both sides to reach cooperation faster. • The carbon tax policy effectively propels the development of CCS-EOR technology. When the carbon tax rises from 30 CNY/t to 120CNY/t, power plants will conduct CCS retrofitting investment two years in advance. Carbon capture and storage with enhanced oil recovery (CCS-EOR) technology plays a crucial role in achieving dual carbon targets in China. And the rapid diffusion of technology requires collaboration among various stakeholders involved in industrial chain of CCS-EOR project and then it will cause conflict of interest among the participants. In order to solve the problem existing in CCS-EOR promotion and propel the rapid deployment of low-carbon technology in China, the paper constructs a tripartite evolutionary game model by incorporating the strategic choices of coal-fired power plants, oilfield enterprises and governments into the framework, explores the respective dynamic evolutionary path of three parties and analyzes the impact of each parameter change on the system evolution results Through the numerical simulation, the paper identifies the optimal evolutionary path to spur the application of CCS-EOR and determine their strategy choices of three involved subjects in the game framework. Based on the sensitivity analysis, results are given as follows: (1) The government's clean electricity subsidy and carbon utilization subsidy have pushed the timing of CCS retrofitting significantly forward, but the initial investment subsidy has little impact on it; (2) Under the cooperation mode of coal-fired power plants and oilfield enterprises, the optimal cost-sharing ratio of the initial investment for coal-fired power plants is about 0.4 to promote both sides to reach cooperation faster. Once it exceeds 0.4, the probability of cooperation between them will be significantly reduced; (3) The carbon tax policy effectively propels the development of CCS-EOR technology. When the carbon tax rises from 30 CNY/t to 120CNY/t, power plants will conduct CCS retrofitting investment two years in advance. [ABSTRACT FROM AUTHOR]

The dependence on fossil fuels is the primary cause of the increased carbon dioxide emissions into the atmosphere that have resulted in drastic global climate changes due to greenhouse effects and associated global warming. Carbon capture and sequestration (CCS) is a multidisciplinary technology that is gaining momentum in the quest to mitigate the effects of CO 2 emissions. In this paper, we review the current status of research pertinent to the geomechanical modeling of CO 2 sequestration and highlight the key research accomplishments, unresolved problems, and pending challenges and opportunities. The paper begins with a brief overview of the geological sequestration process and then proceeds to review the main aspects of geomechanical modeling, including different numerical methods for modeling the reservoir pressure, ground uplift due to pressure buildup, caprock fault reactivation, carbon dioxide leakage, and induced seismicity. The effects of the number and distribution of injection and production wells on the pore pressure buildup are discussed. Finally, a topical overview of monitoring techniques for stored carbon dioxide is presented. [Display omitted] • Geomechanical modeling of sequestration sites is essential to ensure stability and safety of the deep geological reservoirs. • The effectiveness of a CO 2 storage geomechanical model is mainly dependent on the choice of numerical method. • Geomechanical modeling monitors the injection induced stress changes, reactivation of existing faults, and ground uplift. • The injected CO 2 should be monitored using various satellite, surface and subsurface techniques to avoid any possible leakage. [ABSTRACT FROM AUTHOR]

• Carbon dioxide capture and mitigation are key to the technological response to combat climate change and reduce CO 2 emissions. • Proposal of a novel system for performance improvement of the conventional post-combustion process. • Thermodynamic, economic, and environmental analyses of the proposed cycles. • The desorption column has the largest contribution to the exergy destruction 257.48 k W. • The solvent regeneration energy decreases to 2.77 G J / t C O 2 , 20.17 % lower compared to the conventional system. An optimum process with a novel method for improving the thermodynamic efficiency of the conventional post-combustion process based on a mono-ethanolamine (MEA) 30 wt% solvent is presented. The presented process, by preheating the rich solvent stream twice and using lean vapor compression (LVC), causes the solvent regeneration energy (E regen) to decrease, the exergy efficiency of the desorption column to increase, and the net CO 2 emission to diminish. According to the simulation results, the solvent regeneration energy in the base process is 3.47 GJ/t CO2 and has a value of 2.77 GJ/t CO2 in the proposed scheme, which exhibits a 20.17% decrease. The exergy analysis showed that the desorption column contributes the most to the exergy destruction in the post-combustion process. According to the performed analysis, in the proposed scheme, the exergy destruction in the desorption column reduces from 476.67 kW to 257.48 kW, which shows a 45.98% decrease. Under these conditions, the exergy efficiency of the desorption column is improved by 12.2%. Comparing E r e g e n parameter with that of previous studies demonstrated that the proposed scheme in this paper has significant superiority regarding optimizing the reboiler's energy. Due to the addition of a compressor, heat exchanger, expansion valve, and separator, the annual capital expenditure (CAPEX y) of the proposed scheme is 13.71% higher than the conventional process, which results in a 12.5% increase in the cost of CO 2 capture ( C o s t C O 2 , c a p t u r e ). [ABSTRACT FROM AUTHOR]

According to the construction of the cascade hydropower stations in the lower reaches of the Yalong River and the ecological environment condition of the river, a medium and long-term optimal dispatching model with the goal of maximizing the power generation benefits of the cascade hydropower stations is established, and the dynamic programming method is used to optimize the solution, so as to obtain the ten-day average maximum power generation of cascade hydropower stations. According to the latest relevant research at home and abroad, it is found that during the power generation process of the hydropower station, the discharge will produce certain greenhouse gas (GHG) emissions during the delivery process. In this paper, the greenhouse gas emissions existing in the power generation process of cascade reservoirs are considered, and the typical values are selected to calculate the average greenhouse gas (mainly CO 2) emissions from 2001 to 2018, twelve plants with strong carbon sequestration and oxygen release capacity and suitable for growing in the basin are selected, and the mitigation and improvement measures of greenhouse gas emissions around the reservoirs in the basin are given. A new research idea is provided for the Yalong River cascade reservoirs to focus on the power generation benefits while reducing the greenhouse gas emission situation to a certain extent. [ABSTRACT FROM AUTHOR]

• Step-by-step procedure to develop the tabulation and map component of UIC class VI permit. • Qualitative risk assessment methodology for all types of wells within AoR penetrating the confining zones. • Highlights the need for crossflow modelling of CO 2 leakage through improperly plugged wells. • Generalized categorization of legacy wells based on geologic penetrations and protections. Carbon Capture & Storage (CCS) refers to capturing the anthropogenic carbon dioxide (CO 2) at a source followed by injecting and storing it safely in the subsurface. The success of the CCS projects therefore heavily relies on how efficiently the confining zones (containment seals) prevent migration of the CO 2 to the surface and/or to the underground sources of drinking water (USDW) through leakage pathways. CCS projects requires drilling of Underground Injection Control (UIC) Class VI wells for permanent storage of CO 2 in subsurface. Detailed information of all the wells within the Area of Review (AoR) is needed to develop the map and tabulation components of the Class VI well permit application. This paper discusses the generic process that can be used by permit applicants to develop the dataset necessary for preparing the map and tabulation components of the Class VI permit application and perform qualitative risk assessment of all the wells within the AoR. This methodology directs the corrective action plans as well as monitoring plans to some extent. Results of the application of the newly developed methodology for wells in Illinois basin is discussed in detail. This methodology can be applied to all wells including orphaned wells, abandoned wells, active oil and gas wells, stratigraphic wells, disposal wells, etc. This methodology generalized categorization of legacy wells that will help in easier comparison of different CCS projects across the globe. The qualitative risk assessment methodology discussed in this paper is a good starting point for developing crossflow modeling. [ABSTRACT FROM AUTHOR]

The escalating global warming has intensified concerns about climate change and prompted a swift shift towards worldwide carbon neutrality and a sustainable future. Among various carbon capture, utilization, and storage technologies, mineral carbonation enables the transformation of waste materials into valuable construction resources while mitigating their adverse impacts on the environment and public health. During the past two decades, mineral carbonation has found widespread application in carbon sequestration, primarily employing industrial by-products, notably those generated within the iron and steel sector. The inherent properties of these by-products, characterized by alkalinity, reactivity for carbonation, widespread availability, and substantial quantities, hold great potential for carbon mitigation. Developing efficient and resilient carbon sequestration protocols utilizing iron and steel by-products is vital, as it addresses key challenges associated with mineral carbonation, such as high costs, slow reaction kinetics, and environmentally detrimental feedstock mining. In this review paper, various carbonation techniques for iron and steel by-products are evaluated and summarized. Different stages of essential carbonation processes are examined, along with their detailed physicochemical mechanisms. The review also explores recent technological advancements in this field, including the utilization of additives, supercritical carbonation, microwave irradiation, and ultrasonic enhancement, while assessing their potential to enhance process efficiency and sustainability. Additionally, the paper critically assesses representative processes from economic, environmental, and health perspectives. By providing an in-depth discussion of scalability, industrial implementations, economic feasibility, environmental toxicity, health impacts, and current technical barriers, this paper presents a comprehensive summary that addresses challenges, opportunities, prospects, and key insights in the field of mineral carbonation using iron and steel by-products. This effort represents a unique contribution to fill critical knowledge gaps in the mineral carbonation of iron and steel by-products, encompassing state-of-the-art technical advances and addressing their economic, environmental, and health implications. [Display omitted] • Mineral carbonation techniques for iron and steel by-products are reviewed. • Technological advances have enhanced process efficiency and economic feasibility. • Processes are assessed for economic, environmental, and health impacts. [ABSTRACT FROM AUTHOR]

• We develop scenarios for how public acceptance may constrain CCS diffusion in Europe. • We show how the type of limited CCS acceptance impacts the energy system over time. • CCS reduction and delay play out differently in industry and the power sector. • Fundamental system changes arise even when CCS is only constrained in power generation. • Additional annual system cost effects in 2050 can vary from -50 to +800 billon $/yr. In this paper we analyse how in Europe large-scale deployment of CO 2 capture and storage (CCS) technology may be hindered by limited public acceptance. We develop scenarios for how public acceptance may constrain the diffusion of CCS, either by reducing the overall amount of installable CCS capacity or by delaying its introduction, and show with an integrated assessment model how the type of limitation in CCS acceptance can critically impact the development of all sectors in the overall energy system over time. We also demonstrate that a reduction or delay in CCS diffusion as a result of critical public opinion can have substantial energy system impacts that differ across not only the nature of acceptance profile but also the sector(s) in which limited public acceptance materializes. Applying a constraint to CCS deployment in both industry and the power sector simultaneously leads to an energy system that is fundamentally different from the one that emerges if the constraint is only applied to the power sector. Depending on how and where CCS diffusion is constrained, net additional annual energy system costs in 2050 can vary between -50 billion up to nearly 800 billon $/yr. [ABSTRACT FROM AUTHOR]

• Modeling a multiple multi-energy systems containing power and heating demands. • Modeling carbon capture and power-to-gas facilities for carbon recycling. • Using carbon transfer for trading carbon between interconnected microgrids. • Using stochastic p-robust optimization to quantify the regret of uncertainties. With the escalating concern of global warming propelled by the rise in Earth's temperature, the need for effective CO 2 management has become crucial. This paper presents an innovative CO 2 elimination approach, wherein a multiple integrated system of energies (MISEs) incorporating sustainable resources, including renewable resources (RENs), plug-in electric vehicles (PEVs), and demand response programs, is optimized. The proposed carbon elimination framework begins by modeling the onsite carbon capturing and recycling within each MISE. To effectively utilize the onsite carbon recycling facilities and achieve carbon neutrality, the proposed model also incorporates carbon transfer capability between MISEs, thereby enhancing the efficiency of overall carbon recycling. Furthermore, a stochastic p-robust optimization technique is proposed to effectively manage uncertainties by combining the advantages of stochastic programming and robust optimization. This uncertainty modeling approach promotes greater utilization of sustainable resources like PEVs and RENs due to their lower operational regrets from economic and environmental perspectives. Based on the simulation results, implementing the p-robust-based regret assessment technique led to the total operation cost increasing by only 2.75 %, while achieving a significant 44.5 % reduction in maximum relative regret. These results underscore the effectiveness of the proposed framework in enhancing both the economic and environmental performance of MISEs. [ABSTRACT FROM AUTHOR]

• A novel surrogate model-based reinforcement learning method is proposed for optimizing CO2 geological storage. • The E2CO model translates to high-fidelity models well and demonstrates robustness in predicting model states and well outputs. • The surrogate model-based reinforcement learning approach achieves efficient training and is adaptable for various optimization tasks. Injecting greenhouse gas (e.g. CO2) into deep underground reservoirs for permanent storage can inadvertently lead to fault reactivation, caprock fracturing and greenhouse gas leakage when the injection-induced stress exceeds the critical threshold. It is essential to monitor the evolution of pressure and the movement of the CO2 plume closely during the injection to allow for timely remediation actions or rapid adjustments to the storage design. Extraction of pre-existing fluids at various stages of the injection process, referred as pressure management, can mitigate associated risks and lessen environmental impact. However, identifying optimal pressure management strategies typically requires thousands of simulations, making the process computationally prohibitive. This paper introduces a novel surrogate model-based reinforcement learning method for devising optimal pressure management strategies for geological CO2 sequestration efficiently. Our approach comprises of two steps. The first step involves developing a surrogate model using the embed to control method, which employs an encoder-transition-decoder structure to learn dynamics in a latent or reduced space. The second step, leveraging this proxy model, utilizes reinforcement learning to find an optimal strategy that maximizes economic benefits while satisfying various control constraints. The reinforcement learning agent receives the latent state representation and immediate reward tailored for CO2 sequestration and choose real-time controls which are subject to predefined engineering constraints in order to maximize the long-term cumulative rewards. To demonstrate its effectiveness, this framework is applied to a compositional simulation model where CO2 is injected into saline aquifer. The results reveal that our surrogate model-based reinforcement learning approach significantly optimizes CO2 sequestration strategies, leading to notable economic gains compared to baseline scenarios. [ABSTRACT FROM AUTHOR]

• We study formate species, a product of CO 2 electrochemical reduction, as an alternative carbon carrier for sequestration and EOR • Formate solution injection yielded greater levels of oil recovery and net carbon storage • Carbon-bearing species resided in the dense aqueous phase without having to rely on petrophysical trapping mechanisms • In establishing carbon tax credit policies and regulations, policymakers should include alternative carbon carriers. As carbon capture, utilization, and storage (CCUS), carbon-dioxide enhanced oil recovery (CO 2 EOR) has inherent shortcomings, such as inefficient oil recovery and carbon storage, and low storage security with mobile CO 2. This paper presents a techno-economic-environmental analysis of using formate species, a product of CO 2 electrochemical reduction, as an alternative carbon carrier for sequestration and EOR in a carbonate oil reservoir in the Gulf of Mexico Basin. CO 2 injection, water-alternating-CO 2 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 CO 2 -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. [ABSTRACT FROM AUTHOR]

In the next decades, CO 2 capture and utilisation (CCU) technologies can contribute to climate change mitigation. The Columbus project is an example of a CCU initiative in which CO 2 is captured from lime production and converted into E-methane via CO 2 methanation. E-methane can serve as fuel for ships and lorries to replace heavy fuel oil and diesel, respectively. This paper aims to assess the environmental impacts of E-methane production via the Columbus process, powered by renewable electricity, and its utilisation in the transport sector benchmarked to conventional fuel production (references) through life cycle assessment (LCA). A basket of products approach was used to also consider the co-products obtained from the Columbus process in the assessment. Both emission and resource based indicators were selected for the LCA. The results show that E-methane production and its utilisation in ships and lorries result in a decrease of the impact on climate change (35 %), particulate matter formation (94 %) and fossil resource use (85 %) compared to the references. For this comparison, the conventional production of the co-products was also taken into account. However, the production and utilisation of this fuel consumes more minerals and metals than the references. The higher mineral and metal extraction from the environment can be explained by the construction of the solar panels required to provide electricity for electrolysis. Future research should focus on the social acceptance and techno-economic assessment of the Columbus process. • CO 2 from lime production is valorised into E-methane via CO 2 methanation. • The environmental sustainability of the Columbus process was evaluated. • A basket-of-products approach was used to also consider the co-products. • The climate change impact decreases when shifting from heavy fuels to E-methane. • Mineral and metal use increases compared to conventional fuel production. [ABSTRACT FROM AUTHOR]

Cement is essential for the construction industry, but its production process generates a large amount of CO 2 , adversely affecting the environment. To address the issue above, carbonation curing serving as one of the efficient carbon reduction approaches is widely adopted benefiting from its advantages of rapidly realizing carbon sequestration and enhancing the performance of cementitious materials. Numerous studies have indicated that the addition of low-reactivity minerals such as limestone, quartz, sandstone, and glass powder accelerates the carbonation reaction of cement composites. However, there is a lack of reviews on the application of low-activity minerals in carbonation-cured cementitious materials. Therefore, this paper presents a comprehensive review regarding the research progress on the application of low-reactivity minerals in carbonation-cured cement-based materials for the first time. This review first introduces the effect of low-activity minerals on the performance of carbonation-cured cement composites. Subsequently, the related mechanism is analyzed. Finally, the future research directions and challenges in this field are emphasized. This work provides insights and references for the application of low-reactivity minerals in carbonation-cured cement-based materials, thus contributing to carbon emission reduction in the cement industry. • Reviewing the application of low-activity minerals in carbonation-cured cement materials. • Summarizing the effect of low-activity minerals on carbonation-cured cement composites. • Analyzing the mechanism of low-activity minerals in carbonation curing. • Emphasizing the challenges of low-activity minerals in carbonation curing. [ABSTRACT FROM AUTHOR]

Mitigating GHG emissions from industries and other sectors of our economy is a vital aspect of having a sustainable economy. This paper offers an in-depth process development and eco-techno-economic performance analysis of different methanol production pathways, namely CCU-assisted electrified reforming and CCS-assisted pathways, in comparison to conventional methanol production using natural gas. Through model simulations with Aspen Plus, eco-techno-economic analyses, and extensive sensitivity analysis, the research aims to provide valuable insights into the economic and environmental implications of these pathways. Our results revealed that our proposed electrified pathways, E-CRM-80 and E-CRM-90, show substantial reductions in capital investment by 27 % and 19 %, in comparison to TRM. In terms of economic viability, the MSP of methanol for E-CRM-80 and E-CRM-90 in regions with cheaper renewable energy sources is $291 and $319/tonne CO 2 , lower than the $377 and $670/tonne CO 2 required for CCS and TRM. Notably, E-CRM-80 and E-CRM-90 surpass CCS in cost when the mitigation credit exceeds $300 and $350/tonne CO 2. The integrated e-TEA/LCA model underscores the significance of electricity consumption in CCU processes, providing insights into the achievable lifecycle GHG reduction across all pathways. In Quebec, characterized by the lowest electricity cost, the electrified pathway requires a reduced life cycle GHG reduction credit, even lower than the CCS technology. For E-CRM-80 and E-CRM-90 to achieve lower GHG mitigation credits than the CCS pathway, the electricity grid must emit less than 37 and 11 g CO 2 /kWh. Conversely, in Alberta, with high electricity prices, CCU pathways are less favorable compared to CCS. [Display omitted] • Development and eco-techno assessment of a novel electrified CO 2 reforming process (E-CRM). • Comparing the e-TEA results with those of other CCU and CCS routes for MeOH production. • E-CRM reduces electricity and H 2 demand compared to TRM, leading to notable cost savings. • E-CRM pathways need lower GHG credits than CCS in regions with low electricity costs. • E-CRM-80 and E-CRM-90 surpass CCS when CO₂ credits exceed $300 and $350/tonne. [ABSTRACT FROM AUTHOR]

Understanding the complicated fluid dynamics and geochemistry coupling behaviors is the key to enhance CO 2 storage efficiency and minimize the risks of leakage and mechanical failure in geologic CO 2 storage (GCS) reservoirs. This review paper aims to discuss recent research advances associated with fluid dynamics and geochemistry coupling in GCS systems. Four research areas, i.e., flow-induced enhancement of mineral dissolution and precipitation, advanced imaging techniques based on digital core analysis techniques, advances in reactive transport modeling, and upscaling approaches from pore-scale to reservoir-scale, are covered by this review. Based on a comprehensive discussion on the research advances in the aforementioned research areas, current challenges and future research needs of fluid dynamics and geochemistry coupling in geologic CO 2 storage are highlighted. Finally, this review discusses how the research in fluid dynamics and geochemistry coupling can help in developing sustainable geologic CO 2 storage strategies that can contribute to achieving carbon neutrality goals. • Fluid dynamics and geochemistry coupling in GCS affects the efficiency and safety of CO 2 storage. • Research advances associated with fluid dynamics and geochemistry coupling in GCS are reviewed. • Challenges to study fluid dynamics and geochemistry coupling in GCS are highlighted. [ABSTRACT FROM AUTHOR]

The growing demand for upgraded electronic products has resulted in a significant amount of waste batteries. In this paper, we propose a low-carbon, scalable mechanochemical waste-to-value strategy to convert spent ZnO from alkaline batteries into Zn-MOF-74, a functional metal–organic framework (MOF), for CO 2 capture. The conversion pathway of ZnO-to-MOF-74 was investigated via structural characterization techniques. Compared with commercial ZnO with a hexagonal prism-like morphology, spent ZnO, exhibiting a rod-shaped morphology, demonstrated greater readiness in transforming into Zn-MOF-74, completing the transformation in nearly 5 h via ball milling and reducing energy consumption by around 50%. Moreover, the CO 2 adsorption capacity of Zn-MOF-74 synthesized using spent ZnO, which is 2.07 mmol/g (at 273 K), is nearly triple that synthesized from commercial ZnO that has a hexagonal prism-shaped morphology. Overall, this study highlights the potential of repurposing spent ZnO in waste valorization, thereby significantly contributing to the advancement of a circular economy. [Display omitted] [ABSTRACT FROM AUTHOR]

• Modeling the environmental aspects of virtual energy hubs with carbon offsetting. • Hedging against uncertainties using a stochastic scenario-oriented analysis. • Risk aversion operation under operational risks driven from chance constraints. • Optimization of hybrid vehicles under both electric and fossil fuel driving modes. Virtual energy hubs (VRHBs) combine dispersed energy resources to enhance the efficient use of various energy sources, grid flexibility, and renewable energy adoption. This paper investigates the adoption of VRHBs with power-to-gas (P2G) facilities and hybrid electric-compressed natural gas vehicles (HNGEVs) in the presence of renewable resources to effectively tackle carbon emissions and increase the flexibility of VRHBs. The proposed P2G facility is constructed from carbon capture to collect carbon pollution from fossil fuel resources and HNGEVs to recycle into synthesis gas in a methanation plant. Furthermore, due to severe uncertainties due to renewable resources and energy consumption intensity, the proposed framework utilizes stochastic-driven chance-constrained optimization, which enables decision-makers in VRHBs to account for the probabilistic nature of uncertainties. Chance-constrained optimization explicitly considers uncertainty through probabilistic constraints, providing a more robust and reliable solution compared to deterministic methods. By modeling uncertainties using chance-constrained programming, VRHBs can manage the economic risks under unexpected worst realizations in uncertainties. Based on the results, the P2G facility leads to a significant reduction in the daily emissions by 63.06 % and 42.77 % observed under no-risk and full-risk conditions, respectively. In addition, the suggested chance-constrained method resulted in a major decrease of 69 % in overall operational costs. [ABSTRACT FROM AUTHOR]

Reducing greenhouse gas emissions in the shipping sector is a challenging task. While renewable fuels stand out as the most promising long-term solution, their near- and mid-term viability is hampered by limited availability and high costs. An alternative approach is onboard carbon capture, which can reduce emissions from new ships as well as retrofitted vessels. This paper examines the techno-economic potential of oxyfuel combustion based carbon capture on ships. The oxyfuel concept uses an oxygen-rich atmosphere in the combustion process, resulting in a mixture of carbon dioxide and water. After the condensation of water, the carbon dioxide rich gas can be directly stored on board. Various onboard oxygen supply concepts are investigated, including different technologies for onboard air separation and liquid oxygen bunkering. Influences on the ship energy system are studied by system simulation of a deep-sea container vessel. Benchmarked against a technologically mature post-combustion carbon capture system, the results show that the oxyfuel concepts have limited competitiveness because of reduced engine efficiencies and high energy demands for onboard oxygen supply. Avoiding onboard oxygen supply by using liquefied oxygen as a byproduct from onshore electrolysis increases energy efficiency and the competitiveness of oxyfuel combustion but requires additional storage space. Sensitivity analyses highlight that the engine combustion concept and engine efficiency are the most critical influences on the techno-economic performance. • Oxyfuel combustion faces significant challenges compared to post combustion concepts • High fuel penalty mainly caused by the drop in efficiency of the combustion engine • The use of onboard liquid oxygen storage tanks offers techno-economic advantages • High potential for significantly reduce total CO 2 emissions with oxyfuel combustion [ABSTRACT FROM AUTHOR]

• A cost-efficient CCS operation cannot be realized without a CO 2 pipeline network. • The paper presents a framework to study different scenarios of a future CO 2 network. • The model uses several geospatial datasets and a dedicated optimization scheme. • The costs of the investigated scenarios range between 1.3 and 3 billion EUR. • The model is flexible and can be used for investigating other scenarios and regions. Carbon capture and storage will be necessary for some industries to reach carbon neutrality. One of the main associated challenges is the design of the network linking the CO 2 sources to the storage sites. Establishing a CO 2 network can be impacted by many uncertainties such as CO 2 amounts, pipeline routes and the locations of emitters and carbon sinks. We present a framework to investigate different scenarios of a future CO 2 network in Germany. The analyses compare the routes and associated costs of different scenarios. The developed model uses several geospatial datasets and an optimization scheme to yield realistic and cost-efficient outcomes. Parameters such as population density and existing infrastructure are integrated to calculate potential routes, which are then used as an input for the developed heuristic model to determine the optimum network. The derived framework is flexible and can be used for investigating other scenarios, regions and settings. The results show that the different scenarios have a profound impact on the optimal layout and costs. The investment costs of the investigated scenarios range between 1.3 and 3 billion EUR. The outcomes are important for academia, industry and policymaking for the ongoing discussions regarding the development of carbon infrastructure. [ABSTRACT FROM AUTHOR]

• The jet structure of pipe leakage under various initial conditions and orifice diameters are obtained. • The leakage near-field parameters under various initial conditions and orifice diameters are obtained. • Experiments reveal the dominant cause of near-field characteristics of pipeline leakage. • Experiments provides input condition parameters for far-field leakage simulations. Accidental leakage poses a significant safety concern for carbon capture, utilization, and storage (CCUS) projects. Understanding the near-field characteristics of leakage is essential for dispersion studies, safety distance calculations, and risk assessment of emergency response to a pipeline leakage. This paper presents a small-scale CO 2 pipeline leakage experiment designed to investigate the transient characteristics of near-field parameters, including temperature, pressure, and jet structure. The study also analyzes the effects of factors such as initial pressure, initial temperature, and leakage orifice diameter on the transient characteristics of the near-field. The experimental results demonstrate that lower initial temperatures lead to higher near-field pressure peaks, while larger orifice diameters result in larger near-field pressure peaks. Furthermore, a larger hole diameter combined with a lower initial temperature and higher initial pressure leads to the negative pressure region in the near-field being farther away from the leakage opening. In the liquid state, the near-field temperature is lower compared to the gaseous state due to the strong liquid-gas flash evaporation. When different orifice diameters are used for depressurization, larger diameters cause a more significant drop in near-field temperature. The study also reveals that the effect of initial temperature on the jet structure is less significant compared to the effect of initial pressure. The primary objective of the experiment was to collect near-field leakage data and analyze the characteristics of near-field leakage. It is hoped that this work will contribute to the improvement of research models that assess the consequences of potential high-pressure pipeline rupture scenarios. [ABSTRACT FROM AUTHOR]

Negative trends of climate change and biodiversity loss are closely linked with farming practices, and it is therefore essential to re-think how agricultural systems can sequester more carbon, and simultaneously create vital ecosystems. The overall aim of this research is to imagine Swedish farms as carbon sinks rather than sources, and how to re-design the current farm- and food system to also address other social, economic, and environmental sustainability challenges. This paper is the outcome of two visioning workshops together with participants in an ongoing initiative called Swedish Carbon Sequestration [Svensk Kolinlagring]. Participants discussed what alternative futures might look like, how they would function, and how to get there. The farm-level visions include perennial crops, keyline design, online farmers markets, increased collaboration between farms, and increased knowledge about soil health. The participants highlight complex interactions between animals, trees, leys, and crops that can support carbon sequestration. They also emphasize the need to increase both farmer's and society's knowledge about soil health and its multiple positive effects on carbon sequestration. In addition, a transformation of the farm- and food system would also contribute with positive effects on farmers income and their autonomy over decision making and long-term planning, in turn also improving farmers' and consumers' health. The participants highlight that the food system will be transformed by changes in consumer demand, increased knowledge and awareness, shortened value chains, and by changing policies and financial support systems to favor farmers who engage with agroecological principles of farming. • We develop future visions of a farm system that supports carbon sequestration. • Increased use of perennials will have multiple societal and environmental benefits. • Farmers envision a future with increased collaboration between farms. • Future policies and support systems need to favor the unconventional farmer. • Farmers envision a transformation of the food system that prioritizes soil health. [ABSTRACT FROM AUTHOR]

Global energy demand is increasing and, despite all the efforts made to develop new sources of clean energy, a considerable part of the energy is still produced by burning fossil fuels. Greenhouse gas emissions from fossil fuel power plants are the major cause of emissions that cause global warming and climate change. Carbon capture and storage is a necessary technological option for eliminating carbon dioxide emissions. The paper presents the main technologies used for CO2 separation from flue gas. [ABSTRACT FROM AUTHOR]

• A new method for quantitatively monitoring CO 2 saturation in depleted gas reservoirs is proposed. • The ratio of the near detector's neutron capture gamma-ray count rate to the far detector's thermal neutron count rate measured by a four-detector pulsed neutron logging tool can effectively differentiate between CO 2 and CH 4. • The new method has higher CO 2 sensitivity compared to conventional count ratio methods. With favorable trap conditions and comprehensive infrastructure, depleted gas reservoirs create ideal spaces for the economic and efficient storage of carbon dioxide (CO 2). Accurate monitoring of CO 2 saturation is important for understanding CO 2 storage efficiency and distribution status. This paper proposes a new method for the quantitative monitoring of CO 2 saturation in CO 2 sequestration projects within depleted gas reservoirs. The new method uses the ratio of the near detector's neutron capture gamma-ray count rate to the far detector's thermal neutron count rate (RCN) measured by a four-detector pulsed neutron logging tool. In this paper, the RCN responses for different CO 2 saturation levels are studied using the Monte Carlo method, and the methods for roughly and accurately calculating CO 2 saturation are given. Moreover, the effects of formation factors such as lithology, clay mineral content, bound water salinity, and borehole environment on the RCN response are studied. Finally, the applicability of the RCN method is verified through a simulation example. The results show that the RCN method not only has high CO 2 sensitivity, but it also can accurately determine CO 2 saturation in depleted gas reservoirs and control the error of CO 2 saturation calculation within 2%. This study offers robust technical support for the evaluation of CO 2 saturation in depleted gas reservoirs. In addition, the proposed method has been proved applicable in the evaluation of CO 2 saturation in low-porosity reservoirs. [ABSTRACT FROM AUTHOR]

• CCUS development among EU countries with the latest progress in the field. • Realization of EGD targets with CCUS technology in EU. • Applicability of benchmarking method to compare environmental profiles. • UK and the Netherlands are among top countries with rapid CCUS development. • Poland and Germany with a high level of difficulty in achieving the EGD targets. Carbon Capture Utilization and Storage (CCUS) is a technology highlighted as one of the tools in climate change mitigation and one of the ways to reach the goal of 1.5℃ set by the Paris Agreement. The European Commission (EC) developed this goal by creating and implementing the European Green Deal (EGD) – the European Union's (EU) environmental policy. This paper provides an analysis of environmental policies and an overview of crucial CCUS projects of selected member states based on a benchmarking analysis of 27+ UK member states. An overall review of a total of 28 countries was undertaken based on economic and environmental factors. Afterward, a benchmarking analysis was performed ranking the countries according to the TOP10 for the selected five categories: total net emissions with international transport, percentage share of the energy sector, percentage share of fossil fuels, percentage share of fossil fuels in the Gross Electricity Production (GEP), and numbers of CCUS projects. Subsequently, a detailed and comprehensive overview of four selected member states was done, with a special focus on the national energy policy towards net-zero emission goals, the role of CCUS in domestic environmental policy, with current projects and facilities development. Finally, this paper outlines how the EGD has reformed the national energy policies of selected member states, and what is the part of CCUS technology in the national efforts towards climate neutrality. [ABSTRACT FROM AUTHOR]

Drones, lasers and satellites measure forests with seemingly unprecedented detail. In Scotland, private companies are bringing these Advanced Measurement Technologies (AMTs) from ecological science to market. Companies offer landowners the chance to independently measure and verify natural capital commodities, such as woodland carbon credits, using these technologies. Drawing from 61 interviews with stakeholders in the Scottish land sector, alongside six months of ethnographic research, this paper explores the climate governance consequences of high-tech forest carbon measurement. The argument develops from the well-established premise within environmental STS that technologies' apparent objectivity and impartiality obscures the political-economic motivations shaping their use. In Scotland, AMTs are reflexively developed to generate increased financial value from forest creation schemes. AMTs find more carbon in forests than standard measurement practices allow. Carbon is 'known not grown': more numerous and legitimate carbon credits can be created through a shift in knowledge practices rather than a material shift in nature-based carbon sequestration. Three epistemic processes allow for more carbon to be 'known not grown'. Firstly, more carbon volume can be identified within a forest by using sophisticated measurement techniques. Secondly, conservative carbon estimates can be bypassed because of the perceived precision of AMTs. Thirdly, AMT developers cultivate a situated form of measurement accuracy by drawing upon a selective uptake of science. This paper argues 'known not grown' is a novel type of mitigation deterrence. It is a dangerous yet increasingly widespread phenomenon in neoliberal environmental governance and requires further empirical investigation. • Carbon measurement is developing along a privatised and technocratic trajectory. • Measurement technologies are taken from science to 'find' more carbon in forests. • Carbon is 'known not grown': more carbon is measured but not necessarily sequestered. • 'Known not grown' is a novel frontier of mitigation deterrence. • Finding natural capital is increasingly likely in neoliberal nature restoration. [ABSTRACT FROM AUTHOR]

CO 2 emissions from industrial processes and their impact on climate change have gradually become major concerns. The amine-based scrubbing technology is considered a viable strategy for capturing CO 2 to alleviate the climate crisis. However, the high expense of CO 2 capture operations is severely hindering the further development of this technology and its application in industry. The catalytic CO 2 desorption strategy has recently attracted considerable attention recently as a low-energy technology, and it has high potential for large-scale implementation. Therefore, in this review, we summarize the latest progresses in solid acid-catalyzed desorption of CO 2 from various amine-rich liquids, especially monoethanolamine (MEA) solution. Solid acid catalysts (SACs) are of six types: metal oxides, molecular sieves, natural clay minerals, composite materials, organic framework materials, and carbon-based materials. These catalysts improve CO 2 desorption through mechanisms that are driven by Lewis acids, Brønsted acids, and basic active sites, as is discussed in depth in this paper. The stability of the catalysts and their advantages and disadvantages are also considered. Finally, based on the characteristics of various catalysts, we comprehensively compare and analyze their industrial potential and provide some prospects regarding their future development. Moreover, to solve certain bottleneck problems in this field, the application prospects of machine learning algorithms in CO 2 desorption have been discussed. Overall, this paper provides a robust theoretical basis and technical reference regarding efficient and inexpensive carbon capture. [Display omitted] • The latest progress of catalytic CO 2 desorption in amine-rich solution was reviewed. • The possible reaction mechanism of catalytic CO 2 desorption by SACs was presented. • CO 2 desorption catalysts were classified into six types in detail. • The activity and stability of SACs for catalytic CO 2 desorption were compared. • Perspectives of future research directions for catalytic CO 2 desorption were presented. [ABSTRACT FROM AUTHOR]

During the long-term CO 2 storage process, the CO 2 –brine–rock interaction (CBRI) may change the elastic - plastic behaviors of sandstone reservoirs, potentially leading to rock damage and CO 2 leakage. A good understanding of the influence of the CBRI on the plastic zone of sandstone is crucial for evaluating the rock fracturing processes. In this paper, three - point bending tests were conducted under both monotonic and cyclic loading conditions, and the digital image correlation technique was used to analyze the elastic and plastic characteristics of the samples. The experimental results showed that the CBRI decreases the yield strength and corresponding crack mouth opening displacement by 25 % and 65%, respectively, thus increasing the probability of fracturing. Additionally, it was found that the CBRI enlarges the plastic zone by about 20 %. The size of the theoretical plastic zone in the sandstone sample for different loads was determined, and the ratio of the plastic zone size in the samples with CO 2 – brine saturation to that without CO 2 – brine saturation was found to be about 1.18. Finally, the mesoscale factors affecting the plastic zone size after CO 2 – brine saturation were analyzed. This study helps to understand the effect of the elastic - plastic behavior of sandstone on reservoir stability during long - term CO 2 storage. • CO 2 –brine–rock interactions increase the size of the plastic zone in sandstones. • Digital image correlation technique quantifies the evolution of the plastic zone. • The mesoscale factors affecting the plastic zone size are analyzed. [ABSTRACT FROM AUTHOR]

Energy transition is leading to a fundamental shift in interstate energy relationships as renewables, hydrogen, critical minerals and other technologies are being increasingly deployed worldwide, intertwined with climate change concern. Evolving bilateral and multilateral cooperation agreements on energy transition signals that the interstate energy relationship is forming differently compared to the fossil fuel-based energy relationships of the previous century. To understand the current landscape of international energy transition cooperation, the paper applied social network analysis to identify the clustering of cooperation between 176 countries and political bodies in energy transition, including renewables, hydrogen and critical minerals, nuclear energy, carbon capture, utilization and storage, and natural gas, by analysing 293 bilateral and multilateral energy cooperation arrangements. Overall, the countries having initiated bilateral cooperation programme, such as China, Japan, and Germany, have an expanded network with other countries under their respective bilateral scheme. It is also observed that both traditional energy exporters and importers are actively forming networks since both explore emerging opportunities driven by energy transition while their motivation may not be identical. Traditional energy exporters attempt to diversify their energy products' portfolio in consideration of the international pressure on decarbonization, whereas traditional energy importers seek opportunities to become an exporter or to secure a supply chain as consumers. For renewables, while China has the highest centrality regarding overall and renewable-specific cooperation, the European Union and United States consistently form clusters in each area of cooperation. With regard to hydrogen and critical minerals, the expected consumer countries are proactively connecting with other countries to secure a sustainable supply chain. It is also found that the European Union and the United States plus Japan tend to create not only bilateral but also multilateral cooperation through alliances and partnerships, making their clustering more solid. • Discussion of evolving inter-state energy relationships in energy transition • Research of 293 energy transition agreements from 176 political bodies • Network analysis between political bodies by using Gephi • Renewables, hydrogen, critical minerals, nuclear, carbon capture and natural gas [ABSTRACT FROM AUTHOR]