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Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The foundation industries in the UK were responsible for emitting 42 Mt CO2eq in 2020, which is approximately 10% of the yearly territorial greenhouse gas emissions. The UK government decarbonisation roadmap issued in 2015 predicted that high-tech strategies such as carbon capture and utilisation, hydrogen and biofuels, as well as electrification of processes are key for achieving the climate mitigating targets by 2050. In this study, a critical assessment was performed on the limitations to achieve these high-tech strategies such as biomass availability, capital investment, and technology readiness. The study is the first to use the UK carbon budget values as the resource limit for the high-tech decarbonisation strategies. The findings show that the significant uncertainty associated with the high-tech scenarios limits their decarbonisation potential by 2050. More importantly, to stay within the mid-century carbon budget for the foundation industries, 20–40% reduction in production, through circular economic strategies such as material efficiency and/or changes in product specifications, is required in order to achieve the decarbonisation targets. [ABSTRACT FROM AUTHOR]

Copyright of Zhejiang Electric Power is the property of Zhejiang Electric Power Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper shows that the π-calculus with implicit matching is no more expressive than CCSγ, a variant of CCS in which the result of a synchronisation of two actions is itself an action subject to relabelling or restriction, rather than the silent action τ. This is done by exhibiting a compositional translation from the π-calculus with implicit matching to CCSγ that is valid up to strong barbed bisimilarity. The full π-calculus can be similarly expressed in CCSγ enriched with the triggering operation of Meije. I also show that these results cannot be recreated with CCS in the rôle of CCSγ, not even up to reduction equivalence, and not even for the asynchronous π-calculus without restriction or replication. Finally, I observe that CCS cannot be encoded in the π-calculus. [ABSTRACT FROM AUTHOR]

Many studies anticipate that carbon capture and sequestration (CCS) will be essential to decarbonizing the U.S. economy. However, prior work has not estimated the time required to develop, approve, and implement a geologic sequestration site in the United States. We generate such an estimate by identifying six clearance points that must be passed before a sequestration site can become operational. For each clearance point (CP), we elicit expert judgments of the time required in the form of probability distributions and then use stochastic simulation to combine and sum the results. We find that, on average, there is a 90% chance that the time required lies between 5.5 and 9.6 y, with an upper bound of 12 y. Even using the most optimistic expert judgements, the lower bound on time is 2.7 y, and the upper bound is 8.3 y. Using the most pessimistic judgements, the lower bound is 3.5 y and the upper bound is 19.2 y. These estimates suggest that strategies must be found to safely accelerate the process. We conclude the paper by discussing seven potential strategies. [ABSTRACT FROM AUTHOR]

With the overconsumption of fossil carbon resources, resulting in a large amount of CO2 and other greenhouse gas emissions, caused by global climate change has become one of the major challenges facing all mankind. At the same time, the development and utilization of coal resources will produce a large amount of coal-based solid wastes containing calcium and magnesium, such as fly ash, desulfurization gypsum and other solid wastes. How to realize efficient CO2 capture and sequestration is a very challenging issue nowadays, as well as the large-scale comprehensive utilization of fly ash, coal gasification slag, and other large-scale heavy polluting industrial solid wastes is still in need of a breakthrough. Under the goal of “double carbon”, CO2 mineralization from coal-based solid waste is a potential strategy to effectively address global warming, and mineral carbonation of coal-based solid wastes containing calcium and magnesium has great prospects for carbon dioxide capture and sequestration (CCS) as well as for the resource-based disposal of solid waste. However, the industrial application bottleneck of CO2 mineralization in coal-based solid waste is still unable to break through. This paper reviews the current development of CO2 mineralization from fly ash (FA), desulfurization gypsum (FGDG), and coal gasification slag (CGS), with the aim of exploring the reasons for their technical limitations. Firstly, this paper briefly elaborates on the pathways for CO2 mineralization of coal based solid waste, revealing the reaction process and principles of CO2 mineralization of coal based solid waste. Secondly, the mineralization potential and process of typical coal-based solid waste were summarized and compared to clarify the mechanism of the regulation of the process parameters on the product properties during CO2 mineralization process. Finally, the performance of CO2 mineralization products from coal-based solid waste was summarized, and the feasibility of the mineralization process and its environmental impact were elucidated using a Life Cycle Assessment (LCA). This paper will provide optimization suggestions on the process technology of coal-based solid waste CO2 mineralization to promote the strategic goal of low-carbon transformation in the coal industry.

At COP28, Carbon Capture, Utilization, and Storage was declared a removal technology whose application must be accelerated. In 2017, the Society of Petroleum Engineers (SPE) published the CO2 Storage Resource Management System (SRMS) as a framework for stakeholder communication. The SRMS guidelines were designed to support the creation of reports that inform readers regarding the contingencies that must be overcome to obtain project approval, uncertainty in the mass of CO2 that can be stored, and the commerciality of the project. However, working examples where the SRMS has been used to communicate project status in the public domain are limited. In 2023, the authors of this paper referred to the SRMS as the standard for completing an expert report, termed a Competent Persons Report (CPR), for the Viking Carbon Capture and Storage (CCS) development in the United Kingdom. During the application of the SRMS framework, challenges were identified in conveying the progress made by the project proponent in identifying and addressing technical risks. This paper describes innovations developed to supplement the SRMS guidelines and improve communication with stakeholders. First, a flowchart was developed to explain a vital interpretation of the SRMS. Next, a defined framework of technical milestones was designed to assess the maturity of a given technical topic within the SRMS. This framework was combined with radial data visualization. The combination allowed multiple storage sites to be compared simultaneously and allowed stakeholders to quickly identify the maturity of technical analysis for any given site. We conclude that improving the consistency and clarity of CCS reporting to stakeholders can help build trust in this emerging industry.

• Novel methodology for variable flow CO 2 pipeline design optimisation. • Utilises logit-normal distribution to describe variable flow scenarios. • Methodology is validated for different flow rates and transport lengths. • Oversized pipeline diameter minimises unitised transport cost. • Oversized design yields lower cost compared to buffer tanks. Pipeline transport has emerged as the most cost-effective method for transporting CO 2 onshore. The CO 2 flow rate is a key factor driving transport costs, underscoring the need to understand the impact of flow rate variability in CO 2 pipeline networks on their design and economics. This paper presents an optimal pipeline design methodology for CO 2 pipelines operating under variable flow that considers the probability distribution of CO 2 flow rate and the pipeline length. The results imply that pipelines designed for optimal performance under variable flow rates often demand a higher level of overdesign compared to pipelines intended for steady-state conditions. Decision-makers must balance the trade-offs between pipeline oversizing and installing multiple pressure boosting stations, especially applicable to large transportation distances and projects of extended duration. The examination of different approaches to pipeline design reveals that a variable flow pipeline design based on mean flow rate is not recommended, because it is incapable of handling the maximum flow rate. This drawback is overcome by adopting the variable flow stochastic pipeline design presented in this paper. [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]

Nonwoven upholstery fabric is a waste product which is mainly generated during upholstered furniture production. The polyester composition makes it problematic to recycle and reuse this product. This study examined the manufacturing process of nonwoven fabric-reinforced plywood composites and their selected mechanical and physical properties. Nonwoven fabric was integrated between veneers bound with urea–formaldehyde resin to improve standard layered composites' mechanical and physical properties. Several board variants were produced, differing in the position of the nonwoven layers in the composite structure. The composites were evaluated for modulus of rupture (MOR), modulus of elasticity (MOE), internal bond, and screw withdrawal resistance, among others. The results showed that the addition of nonwoven fabric significantly improved some properties, like internal bond and screw withdrawal resistance. Variants with strategically placed nonwoven layers showed the highest performance increases. The results underscore the potential of nonwoven fabric as an effective reinforcing material, offering a path to developing high-performance plywood composites suitable for demanding applications. Another environmental advantage is that the nonwoven fabric waste used in the tested plywood production has not been subjected to burning or landfilling but, through its incorporation into plywood structure, has positively contributed to the Carbon Capture and Storage (CCS) policy. The findings advocate for a circular economy approach, in which industrial waste is effectively repurposed, contributing to the development of green materials in the wood-based composite industry. [ABSTRACT FROM AUTHOR]

The article presents carbon capture and storage, CCS, as a climate change mitigation method. Many industrial processes, such as the manufacture of cement, the metallurgical industry, and the production of electricity from fossil fuels, produce large CO2 quantities. Carbon capture and storage is a method for these industrial areas to become carbon neutral for the environment. To combat climate change, the EU wants to achieve climate neutrality by 2050, and this goal, along with an intermediate goal of reducing emissions by 55% by 2030, is enshrined in the European Climate Law. The EU has launched various initiatives to achieve these goals, one of which is the 'Fit for 55' legislation. The first step that countries wanting to apply these technologies must take is the evaluation of the underground CO2 storage potential. The potential for CO2 storage in the depleted hydrocarbon reservoirs in Oltenia, one of the eight regions of Romania, makes it possible to develop safe long-term storage projects for the neighboring power plants currently producing energy from burning coal or hydrocarbons. The results of dynamic simulations of CO2 storage in one of these geological structures, Bradesti, which hosts depleted hydrocarbon reservoirs, using a numerical simulator are successfully presented for the neighboring Isalnita Power Plant. In this case, the impact on the environment and climate will be minimal and in alignment with the European Union's long-term objectives. Our study also opens the path for future similar analyses. [ABSTRACT FROM AUTHOR]

The extraction of current characteristics from the opening and closing coils is a crucial method for monitoring the state of high-voltage circuit breakers. Based on the waveform patterns of the opening and closing coil currents in high-voltage circuit breakers， the paper investigates a corner point extraction method of current waveform based on local thresholds of curvature scale space （CCS）. Subsequently， the characteristic curves of current at actual corner points are used to precisely monitor the mechanical state of high-voltage circuit breakers. Calculations based on the measured opening and closing coil currents from high-voltage circuit breakers in a specific substation indicate that the proposed local threshold method of the CCS can accurately identify the waveform features of the opening and closing coil currents. The mechanical state monitoring of high-voltage circuit breakers based on the characteristic curves of opening and closing coil currents shows excellent results. The research findings can provide crucial references for the mechanical state monitoring of high-voltage circuit breakers.

The implementation of emission reduction and carbon reduction measures and the implementation of the “double carbon” goal are important transformation opportunity for coal chemical enterprises to move towards high-end,diversified and low-carbon development. Shaanxi Coal Industry Group Yulin Chemical planned a 4 million ton/year carbon dioxide capture, transportation and storage (CCS) demonstration project and carried out a 400000 ton/year pilot test project to help the country reach carbon peak and carbon neutrality. Based on the experience of Shenhua 100000 ton CCS demonstration project and CO2 produced in the 1.8 million ton/year ethylene glycol project, two supercritical CO2 storage processes, high purity (98.94%) and low purity (77.78%), are designed in this paper; Based on the understanding of Triassic and Permian salt water layers in the eastern Ordos Basin, three sets of geological salt water layers (Liujiagou Formation, Shiqianfeng Formation and Shihezi Formation) with good physical properties and great CO2 storage potential were found.After in-depth evaluation and analysis of CO2 storage layer cover and storage capacity, it is believed that the best storage environment for CO2 in salt water layer over 1000 meters. By designing four injection and storage Wells and combining with the numerical simulation method, the storage operation mechanism of 400000 ton/year CO2 is studied and analyzed, and it is theoretically feasible; It is designed to use PNX logging, downhole optical fiber sensing and surface InSAR monitoring methods to build an integrated monitoring and management platform for CO2 from wellbore to reservoir and then to reservoir diffusion; From the perspective of CCS’s current economic and technological costs, industrial policy development, opportunities and challenges,the development of CCS in coal mining chemical industry has great potential.

Abstract Disc cutters are essential for full-section hard-rock tunnel boring machines. The performance of these devices directly affects tunnel engineering costs and duration. This paper proposes a sinusoidal variable cross-section (VCS) cutter ring and design method and establishes a digital model. Rock-like materials are simulated with a finite element model, and the model validity is verified via rock simulation mechanics tests. A disc cutter rolling rock simulation model for a linear cutting machine is also established, and simulation tests are performed for single- and three-cutter rolling using sinusoidal VCSs and constant cross-section (CCS) cutter models, respectively. The stress and energy changes for the cutters and rock-like material damage area were compared via simulation, confirming that some sinusoidal VCS cutter rings do less work on rock-like materials and cause larger crushing areas under the same engineering parameters; therefore, these cutter rings have smaller specific energies. The sinusoidal VCS cutter ring performance is 7% greater than that of CCS on average under single-cutter simulation, and the intermediate cutter performance of the intermediate cutter is 9% greater than that of CCS on average under three-cutter simulation. Thus, sinusoidal VCS cutter rings offer improved rock damage performance, and further research and application of this technology will improve the working efficiency of tunnel boring machines.

• Proposed BECCS deployment criteria are based on socio-enviro-economic objectives. • Life cycle emissions and carbon abatement costs are calculated. • Some of the BECCS pathways are less likely to achieve net negative emissions. • Balancing between socioeconomic aspects such as local job creation opportunities, cost, feedstock supply chain disruptions, and emission reduction targets is discussed. Countries are considering different options to achieve net zero emissions including Bioenergy with carbon capture and storage (BECCS), which is the process of capturing and storing CO 2 from processes that use bioenergy to produce heat, electricity, or biofuels. However, this technology faces sustainability concerns and possesses complex value chains of its emissions. Adding further to this complexity, the literature indicates two opposing views with respect to the potential of BECCS in terms of being able (or unable) to achieve negative emissions. Hence, this paper analyzes in detail a wide range of BECCS pathways in terms of their ability to achieve negative emissions along with their associated costs. Out of seven assessed pathways, our analysis shows that corn to ethanol and biomethane production from maize BECCS pathway in the USA, biomethane production from wet manure in Europe, and baling of straw pellets with trans-Atlantic shipment can achieve negative emissions at a cost of 50, 108, 159, and 232 dollars per ton of CO 2 ($/tCO 2) respectively. Other technologies like poplar pellets, forest residue, and agricultural residue with trans-Atlantic shipment are not able to achieve negative emissions. [ABSTRACT FROM AUTHOR]

• The damage of CO 2 transport infrastructure stems from the characteristics of working fluid and environment. • The development of damage is influenced by many factors like pressure, temperature, flow rate, impurities and materials. • Corrosion perforation, erosion, cracking, debonding and physical-chemical coupling accelerate damage. Carbon dioxide capture and storage (CCS), the bottom covering technology for environmental protection and energy transformation, plays a vital role in reducing CO 2 emissions and has become an international research hotspot. The safe operation of CO 2 transport infrastructure is crucial to ensure the smooth implementation of carbon reduction actions. However, the understanding of disasters in carbon transmission infrastructure is not comprehensive and profound enough since CCS is still developing, which leads to few engineering standards on disaster prevention and mitigation of CO 2 transport infrastructure. This paper provides detailed reviews, including the composition and characteristics of carbon transmission infrastructure, failure mechanisms. It is concluded that the characteristics of CO 2 transport infrastructure damage fundamentally stems from the working fluid and environment, and novelty pointed out that future research hotspots are damage under multi-field coupling, damage detection and monitoring, design to reduce damage and repair after damage. The summary of existing research will be helpful for future academic research and engineering practice of CO 2 transport infrastructure disaster prevention and mitigation. [ABSTRACT FROM AUTHOR]

To ensure the safety of carbon dioxide (CO 2) geological storage, it is important to effectively monitor the pore pressure, reservoir deformation and fluid plume migration, which poses new challenges to monitoring techniques and tools. In this paper, an innovative monitoring method is presented based on distributed fiber optic strain sensing (DFOSS) to detect the strain response distribution induced by fluid injection in real time. The original strain field distribution in the reservoir rock and the effect of the effective stress on the strain response were obtained for different confining and pore pressure combinations. Then, the rock strain during displacement was measured to dynamically monitor the movement front of the wetting phase. The results showed that the core strain response curves under the influence of the confining and pore pressures exhibit significant edge effects, with lower strain values in the vicinity of the artificial confinement facility than in the reservoir. In addition, the overall strain response exhibited an increase corresponding to the increase in the confining pressure. A higher confining pressure was observed to mitigate the pore pressure expansion-related strain in the rock itself. This proves that the selection of a large-depth subsurface reservoir could help to increase the CO 2 injection pressure and rate, and the formation pressure threshold value identified in this study varied between 6 to8 MPa. Furthermore, the full-field strain history showed that fiber optic technology can be employed to accurately monitor the detailed characteristics of front movement and core deformation during wetting fluid displacement, including the history of the strain distribution due to two-phase motion and the change in the two-phase moving speed. The analysis results collectively validated the applicability of this monitoring technique for core-scale testing. The data and conclusions obtained could contribute to a deeper comprehension of the DFOSS reservoir monitoring capability. Furthermore, these findings hold relevance for subsequent experimental analyses, numerical simulations, and field applications at carbon capture and storage sites. • Distributed fiber optic strain sensing is utilized to observe the strain field and edge effect in a CO 2 storage reservoir. • High formation pressures are effective in reducing reservoir deformation during fluid injection. • The speed of front movement during fluid displacement could be monitored by distributed fiber optic strain sensing. [ABSTRACT FROM AUTHOR]

Gamma-alumina (γ-Al2O3) is an essential support material in dry sorbents used to capture CO2 from flue gas. This study explores the deactivation of potassium-based γ-Al2O3 sorbents due to by-products such as KAl(CO3)(OH)2 during CO2 capture. We synthesized sorbents with K2CO3 loadings of 5, 10, 20, and 30 wt% and subjected them to repeated capture and regeneration cycles. The results show significant variations in the deactivation degree: the sorbent with 5 wt% K2CO3 exhibited a 100% deactivation rate, while the 30 wt% variant showed a markedly reduced rate of 44.6%. These findings highlight the impact of the formation of KAl(CO3)(OH)2 at the interface between K2CO3 and γ-Al2O3 on sorbent deactivation. An equation that can be used to predict the final CO2 capture capacity based on the ratio of active material to support was proposed using these results. [ABSTRACT FROM AUTHOR]

Conventional Carbon Capture and Storage (CCS) operations use the direct injection of CO2 in a gaseous phase from the surface as a carbon carrier. Due to CO2 properties under reservoir conditions with lower density and viscosity than in situ brine, CO2 flux is mainly gravity-dominated. CO2 moves toward the top and accumulates below the top seal, thus reinforcing the risk of possible leakage to the surface through unexpected hydraulic paths (e.g., reactivated faults, fractures, and abandoned wells) or in sites without an effective sealing caprock. Considering the risks, the potential benefits of the interplay between CO2 and an aqueous solution of formate ions (HCOO¯) were evaluated when combined to control CO2 gravity segregation in porous media. Three combined strategies were evaluated and compared with those where either pure CO2 or a formate solution was injected. The first strategy consisted of a pre-flush of formate solution followed by continuous CO2 injection, and it was not effective in controlling the vertical propagation of the CO2 plume. However, the injection of a formate solution slug in a continuous or alternated way, simultaneously with the CO2 continuous injection, was effective in slowing down the vertical migration of the CO2 plume and keeping it permanently stationary deeper than the surface depth. [ABSTRACT FROM AUTHOR]

The planned pilot CO2 storage Zar-3 is an oil field with a gas cap in the final production stage in the SE Czech Republic. It is composed of a dolomite Jurassic reservoir sealed by three different formations that differ significantly in lithology. Previous studies left open questions on the nature of pore space and connectivity and the quality of the seal in the future CO2 storage complex. Microscopic petrography of the reservoir suggests dolomitisation in shallow water followed by karstification and brecciation with fracture-correct-dominated porosity. The seal horizons have porosity limited to the micro- and nanoscales. The oil consists of significantly biodegraded black oil of Jurassic origin mixed with less biodegraded gasoline-range hydrocarbons. Biomarkers in the caprock bitumens trapped in nanopores show a genetic relationship to the reservoir oil. Gas in the not yet fully depleted gas cap of the field is of thermogenic origin with no contribution of microbial methane. The formation water has total dissolved solids typical of isolated brines not diluted by infiltrated fresh water. The geochemical characteristics of the storage system together with the fact that the initial oil column is about 105 m tall with another 150 m of gas cap suggest that the seals are efficient and the Zar-3 future storage complex is tight and safe. [ABSTRACT FROM AUTHOR]

Carbon Capture and Storage (CCS) stands as a pivotal technological stride toward a sustainable future, with the practice of injecting supercritical CO2 into subsurface formations being already an established practice for enhanced oil recovery operations. The overarching objective of CCS is to protract the operational viability and sustainability of platforms and oilfields, thereby facilitating a seamless transition towards sustainable practices. This study introduces a comprehensive framework for optimizing well placement in CCS operations, employing a derivative-free method known as Bayesian Optimization. The development plan is tailored for scenarios featuring aquifers devoid of flow boundaries, incorporating production wells tasked with controlling pressure buildup and injection wells dedicated to CO2 sequestration. Notably, the wells operate under group control, signifying predefined injection and production targets and constraints that must be adhered to throughout the project's lifespan. As a result, the objective function remains invariant under specific permutations of the well locations. Our investigation delves into the efficacy of Bayesian Optimization under the introduced permutation invariance. The results reveal that it demonstrates critical efficiency in handling the optimization task extremely fast. In essence, this study advocates for the efficacy of Bayesian Optimization in the context of optimizing well placement for CCS operations, emphasizing its potential as a preferred methodology for enhancing sustainability in the energy sector. [ABSTRACT FROM AUTHOR]

Shear wave velocity (Vs) has significant applications in geoengineering investigations. With the ongoing rise in carbon capture and storage (CCS) initiatives, the role of Vs in monitoring the CO2 sequestration sites is escalating. Although many studies have been conducted to assess CCS-induced risks, no inclusive research has been conducted integrating those investigations. This study strives to collate and integrate the applications of Vs in geoscience with an emphasis on CCS risk assessment. Based on this research, major CCS-induced risks were detected: induced seismicity, caprock failure, groundwater contamination, fault reactivation, and reservoir deformation. These risks were inclusively described, and the mathematical formulations incorporating the Vs parameter in risk analysis were elaborated. It was concluded that Vs applications can be further extended in monitoring CO2 plume migration, optimizing CO2 injection pressures, preventing shallow water contamination, and predicting CCS-induced seismic events. All these applications require fully coupled hydromechanical analysis based on poroelasticity theory. Hence, various factors including pore pressure, in situ stresses, faults distribution, and poroelastic parameters must be carefully determined before the CO2 injection phase. The mathematical formulations presented in the present study are quite applicable for granting the safety and long-term success of subsurface carbon sequestration. [ABSTRACT FROM AUTHOR]

The failure mechanism of thermal gate oxide in silicon carbide (SiC) power metal oxide semiconductor field effect transistors (MOSFETs), whether it is field-driven breakdown or charge-driven breakdown, has always been a controversial topic. Previous studies have demonstrated that the failure time of thermally grown silicon dioxide (SiO2) on SiC stressed with a constant voltage is indicated as charge driven rather than field driven through the observation of Weibull Slope β. Considering the importance of the accurate failure mechanism for the thermal gate oxide lifetime prediction model of time-dependent dielectric breakdown (TDDB), charge-driven breakdown needs to be further fundamentally justified. In this work, the charge-to-breakdown ( Q B D ) of the thermal gate oxide in a type of commercial planar SiC power MOSFETs, under the constant current stress (CCS), constant voltage stress (CVS), and pulsed voltage stress (PVS) are extracted, respectively. A mathematical electron trapping model in thermal SiO2 grown on single crystal silicon (Si) under CCS, which was proposed by M. Liang et al., is proven to work equally well with thermal SiO2 grown on SiC and used to deduce the Q B D model of the device under test (DUT). Compared with the Q B D obtained under the three stress conditions, the charge-driven breakdown mechanism is validated in the thermal gate oxide of SiC power MOSFETs. [ABSTRACT FROM AUTHOR]

This study summarizes the OASIS (Overburden Analysis and Seal Integrity Study for CO 2 Sequestration in the North Sea) project that focuses on assessing the containment risks associated with the geological carbon sequestration (CCS) of the Northern Lights project. CCS is viewed as one of the most effective solutions for reducing carbon emissions, as it captures carbon dioxide from point sources and permanently stores it in suitable geological formations. However, injecting CO 2 into the subsurface may have mechanical consequences, including fault reactivation, top seal fracturing, surface heave, etc. This study proposes an interdisciplinary workflow to characterize the caprock, faults, and overburden associated with CCS projects in the Horda Platform area, to improve injection-induced containment risk assessment. Our findings show that the proposed workflows and tools effectively characterize stress-related mechanical hazards. However, due to the complex nature of rocks, it is challenging to evaluate the top seal integrity using a single method. Therefore, the proposed interdisciplinary approach is more effective for any fluid injection site's characterization, given the complex nature of the subsurface and its behavior under injection-induced stress changes. This research paper adds knowledge about the top seal integrity assessment and the reliability of injected CO 2 , making CCS projects more reliable and safer. Although this study focuses on the northern North Sea, the proposed methods are equally applicable globally to characterize subsurface CO 2 storage sites. Apart from CCS projects, these research results can benefit other subsurface injection projects, such as water injection for reservoir management, wastewater injection for disposal, hydrogen storage, and hydraulic fracturing for unconventional hydrocarbon resources. • Brittleness indices property can reflect the rock integrity. • Seismic inverted properties resolve the data limitation issues within the overburden intervals. • An analytical structural reliability model can help evaluate the top sealing risks quickly. • Overburden interval rock properties must be realistic in any 3D field-scale geological models. • An interdisciplinary workflow is required for subsurface CCS site characterization. [ABSTRACT FROM AUTHOR]

The production of biohydrogen with negative CO2 emissions through the steam methane reforming of biomethane, coupled with carbon capture and storage, represents a promising technology, particularly for industries that are difficult to electrify. In spite of the maturity of this technology, which is currently employed in the production of grey and blue hydrogen, a detailed cost model that considers the entire supply chain is lacking in the literature. This study addresses this gap by applying correlations derived from actual facilities producing grey and blue hydrogen to calculate the CAPEX, while exploring various feedstock combinations for biogas generation to assess the OPEX. The analysis also includes logistic aspects, such as decentralised biogas production and the transportation and storage of CO2. The levelized cost of golden hydrogen is estimated to range from EUR 1.84 to 2.88/kg, compared to EUR 1.47/kg for grey hydrogen and EUR 1.93/kg for blue hydrogen, assuming a natural gas cost of EUR 25/MWh and excluding the CO2 tax. This range increases to between 3.84 and 2.92, with a natural gas cost of EUR 40/MWh with the inclusion of the CO2 tax. A comparison with conventional green hydrogen is performed, highlighting both prices and potential, thereby offering valuable information for decision-making. [ABSTRACT FROM AUTHOR]

The efficacy of alumina-sol based coatings in a water-free atmosphere at high temperatures suggests a potential solution for enhancing the corrosion resistance of high-alloyed steels in Carbon Capture and Storage (CCS) environments. In this study, coupons of X20Cr13, designed for use as injection pipes with 13% Chromium and 0.20% Carbon (1.4021, AISI 420), were sol-gel coated with water and ethanol-based alumina. These coated coupons were then exposed to CO2-saturated saline aquifer water, simulating conditions in the Northern German Basin, for 1000 h at ambient pressure and 60 °C. Corrosion fatigue experiments were also conducted using specimens of X5CrNiMoCuNb16-4 (1.4542, AISI 630), a suitable candidate for geothermal applications, to assess the impact of the ethanol-based coating on the number of cycles to failure at different stress amplitudes. Unfortunately, the coating exhibited early spallation, resulting in corrosion kinetics and corrosion fatigue data identical to those of uncoated specimens. Consequently, the initially promising Boehmit coating is deemed unsuitable for CCS applications and further research therefore not advisable. [ABSTRACT FROM AUTHOR]

Featured Application: The findings of this study offer support for the design of laboratory experiments, monitoring indicators, and the selection of parameters for history matching, ultimately enhancing the accuracy of databases of mineral reactions induced by CO2 injection. Numerical simulation is a commonly employed technique for studying carbon dioxide (CO2) storage processes in porous media, particularly saline aquifers. It enables the representation of diverse trapping mechanisms and the assessment of CO2 retention capacity within the subsurface. The intricate physicochemical phenomena involved necessitate the incorporation of multiphase flow, accurate depiction of fluid and rock properties, and their interactions. Among these factors, geochemical reaction rates and mechanisms are pivotal for successful CO2 trapping in carbonate reactive rocks. However, research on kinetic parameters and the influence of lithology on CO2 storage remains limited. This limitation is partly due to the challenges faced in laboratory experiments, where the time scale of the reactions and the lack of in situ conditions hinder accurate measurement of mineral reaction rates. This study employs proxy models constructed using response surfaces calibrated with simulation results to address uncertainties associated with geochemical reactions. Monte Carlo simulation is utilized to explore a broader range of parameters and identify influential factors affecting CO2 mineralization. The findings indicate that an open database containing kinetic parameters can support uncertainty assessment. Additionally, the proxy models effectively represent objective functions related to CO2 injectivity and mineralization, with calcite dissolution playing a predominant role. pH, calcite concentration, and CO2 injection rate significantly impact dolomite precipitation, while quartz content remains unaffected. [ABSTRACT FROM AUTHOR]

Among the technologies for the recovery of energy from waste, in particular residual municipal solid waste (rMSW), combustion is the most widely used thermo-chemical treatment process associated with thermal and electric power production by a steam cycle, named, shortly, Waste to Energy (WtE). Today, more than 500 WtE plants in the EU, about 400 in China and 76 in the USA are in operation, based on efficient technologies and advanced air pollution control systems. Energy recovery can be accomplished also by means of gasification; however, the presence of impurities together with the atmospheric pressure, at which syngas is normally produced, impose the feeding of syngas to a conventional steam cycle, leading to generally lower performances than WtE. The energy recovered by WtE offsets traditional energy sources such as fossil fuels and related emissions, providing savings in term of climate change. However, the savings obtainable by replacing electricity and/or heat will diminish as the energy systems will hopefully become increasingly renewable. Over this medium–long-term horizon, one possibility is to capture the CO2 from WtE flue gases and to store/use it. From the life cycle assessment perspective, it has been calculated that the introduction of CO2 capture and storage in WtE, despite energy penalties, is able to reduce the impact on climate change. The alternative approach, proposed to contain the emissions of greenhouse gases in the thermal treatment of waste, is using the carbon contained in it to produce commonly used chemical compounds (waste to chemicals). The benefits, in terms of reductions of greenhouse gases, are expected from the possibility of obtaining chemicals that can replace their analogue normally produced from fossil sources. To date, only one WtC demonstration plant is operating by being fed by rMSW-derived waste, and some similar initiatives are planned, but still adequate assurances in terms of robust knowledge of the involved complex processes, above all, if applied to highly inhomogeneous feed streams such as those obtained from rMSW, are not available. Once the several initiatives come to completion, it will enable waste management professionals to assess performance and to begin to consider such a facility in their planning. [ABSTRACT FROM AUTHOR]

The exponential increase in greenhouse gas emissions necessitates urgent measures to mitigate climate change impacts. Carbon capture and storage (CCS) has emerged as a promising solution, capturing CO2 from industrial processes and storing it underground. However, CCS implementation poses risks that demand sophisticated modeling. This review focuses on the numerical modeling of CO2 plume dispersion from reservoir leaks during offshore CCS projects, including near- and far-field modeling and the comparison between Lagrangian and Eulerian modeling in particular. Near-field modeling examines CO2 behavior in jet plume, considering depth-related changes. Far-field modeling, employing Eulerian and Lagrangian methods, evaluates dispersion in marine environments. Case studies illustrate the complexity and uniqueness of CO2 dispersion events. The Lagrangian approach emphasizes gas bubble tracking, while the Eulerian approach employs fixed grid systems for detailed hydrodynamic modeling. Both approaches contribute valuable insights, with Eulerian models excelling in site-specific complexities and Lagrangian models offering computational efficiency. A hybrid approach may offer a comprehensive understanding of CO2 dispersion. [ABSTRACT FROM AUTHOR]

The escalating atmospheric concentrations of carbon dioxide (CO2) due to human pursuit which includes fossil fuel combustion, deforestation, and industrial production make contributions considerably to international warming and climate change. Carbon capture and storage (CCS) and carbon capture and usage (CCU) technology provide viable solutions for mitigating those emissions. This paper critiques various CCS and CCU techniques that specialize of their ability applications, stressful situations, and environmental impacts. While CCS technologies provide promising consequences in decreasing international warming capability, they're associated with better acidification and human toxicity in comparison to standard techniques. Alternatively, CCU technologies present an opportunity to convert CO2 into valuable products, thereby imparting a sustainable approach to greenhouse gas reduction. But, these technology face challenges consisting of high expenses, energy consequences, and the need for social recognition. This study provides a comprehensive assessment of modern CCS and CCU technologies, evaluates their environmental affects, and discusses future prospects for their implementation in reducing industrial CO2 emissions.

In this study, ultra fine drop (<10pl) volume measurement technics were developed using chromatic confocal sensor(CCS). A printing pattern was printed on the substrate by printing equipment, and each sensor measures the height of the drop surface and by integrating them, the drop volume could be determined. To evaluate its performance, measurement accuracy, and the repeatability was determined. The measurement accuracy can be obtained by comparing the same drop volume measured by the confocal microscope. For the measurement repeatability, the same drop volume was measured for several times and its maximum and minimum value was used to determine. As a result, CCS showed a good measurement performance with measurement accuracy of more than 0.90 (R 2 in least square) and measurement repeatability of over 0.95. [ABSTRACT FROM AUTHOR]