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One of society’s major current challenges is carbon dioxide emissions and their consequences. In this context, new technologies for carbon dioxide (CO2) capture have attracted much attention. One of these is carbon capture and utilization (CCU). This work focuses on the latest trends in a holistic approach to carbon dioxide capture and utilization. Absorption, adsorption, membranes, and chemical looping are considered for CO2 capture. Each CO2 capture technology is described, and its benefits and drawbacks are discussed. For the use of carbon dioxide, various possible applications of CCU are described, starting with the utilization of carbon dioxide in agriculture and proceeding to the conversion of CO2 into fuels (catalytic processes), chemicals (photocatalytic processes), polymers, and building supplies. For decades, carbon dioxide has been used in industrial processes, such as CO2-enhanced oil recovery, the food industry, organic compound production (such as urea), water treatment, and, therefore, the production of flame retardants and coolants. There also are several new CO2-utilization technologies at various stages of development and exploitation, such as electrochemical conversion to fuels, CO2-enhanced oil recovery, and supercritical CO2. At the end of this review, future opportunities are discussed regarding machine learning (ML) and life cycle assessment (LCA).

The objective of this study is to assess the technical and economic potential of four alternative processes suitable for post-combustion CO2 capture from natural gas-fired power plants. These include: CO2 permeable membranes; molten carbonate fuel cells (MCFCs); pressurized CO2 absorption integrated with a multi-shaft gas turbine and heat recovery steam cycle; and supersonic flow-driven CO2 anti-sublimation and inertial separation. A common technical and economic framework is defined, and the performance and costs of the systems are evaluated based on process simulations and preliminary sizing. A state-of-the-art natural gas combined cycle (NGCC) without CO2 capture is taken as the reference case, whereas the same NGCC designed with CO2 capture (using chemical absorption with aqueous monoethanolamine solvent) is used as a base case. In an additional benchmarking case, the same NGCC is equipped with aqueous piperazine (PZ) CO2 absorption, to assess the techno-economic perspective of an advanced amine solvent. The comparison highlights that a combined cycle integrated with MCFCs looks the most attractive technology, both in terms of energy penalty and economics, i.e., CO2 avoided cost of 49$/tCO2 avoided, and the specific primary energy consumption per unit of CO2 avoided (SPECCA) equal to 0.31 MJLHV/kgCO2 avoided. The second-best capture technology is PZ scrubbing (SPECCA = 2.73 MJLHV/kgCO2 avoided and cost of CO2 avoided = 68 $ /tCO2 avoided), followed by the monoethanolamine (MEA) base case (SPECCA = 3.34 MJLHV/kgCO2 avoided and cost of CO2 avoided = 75 $/tCO2 avoided), and the supersonic flow driven CO2 anti-sublimation and inertial separation system and CO2 permeable membranes. The analysis shows that the integrated MCFC–NGCC systems allow the capture of CO2 with considerable reductions in energy penalty and costs.

Direct Air Capture (DAC) is a promising technology to fight climate change by capturing carbon dioxide (CO2) from the air. For DAC to be a negative emissions technology, the captured CO2 must be removed permanently, but can also be used as a net-zero technology to produce sustainable chemicals, fuels or other materials. This review presents a comprehensive survey of recent advancements, challenges, and potential applications of DAC technology, with an emphasis on the recent rapid increase in the number of DAC developers, the majority of them being founded in the past 4 years. Through pilot projects and recent commercial deployments, several DAC companies have made significant advances and demonstrated their scalability. Cost and energy efficiency remain significant impediments to the wide deployment of DAC. Integration with emission-free energy sources and utilization of waste heat are being researched to boost the total energy efficiency of DAC systems. Further research of electrochemical technologies for regeneration or direct capture are needed, as well as the development of new, modified, or hybrid adsorbents for improved capture efficiencies. Moreover, favorable regulations and financial incentives are crucial for enhancing the viability of DAC projects and will need to substantially increase if Paris Agreement goals are to be achieved.

Cement manufacturing is one of the most energy and CO2 intensive industries. With the growth of cement production, CO2 emissions are increasing rapidly too. Carbon capture and storage is the most feasible new technology option to reduce CO2 emissions in the cement industry. More research on environmental impacts is required to provide the theoretical basis for the implementation of carbon capture and storage in cement production. In this paper, GaBi software and scenario analysis were employed to quantitatively analyze and compare the environmental impacts of cement production with and without carbon capture and storage technology, from the perspective of a life-cycle assessment; aiming to promote sustainable development of the cement industry. Results of two carbon capture and storage scenarios show decreases in the impacts of global warming potential and some environmental impacts. However, other scenarios show a significant increase in other environmental impacts. In particular, post-combustion carbon capture technology can bring a more pronounced increase in toxicity potential. Therefore, effective measures must be taken into account to reduce the impact of toxicity when carbon capture and storage is employed in cement production. CO2 transport and storage account for only a small proportion of environmental impacts. For post-combustion carbon capture, most of the environmental impacts come from the unit of combined heat and power and carbon capture, with the background production of MonoEthanolAmine contributing significantly. In combined heat and power plants, natural gas is more advantageous than a 10% coal-saving, and thermal efficiency is a key parameter affecting the environmental impacts. Future research should focus on exploring cleaner and effective absorbents or seeking the alternative fuel in combined heat and power plants for post-combustion carbon capture. If the power industry is the first to deploy carbon capture and storage, oxy-combustion carbon capture is an excellent choice for the cement industry.

The Calcium-Looping (CaL) process has emerged in the last years as a promising technology to face two key challenges within the future energy scenario: energy storage in renewable energy-based plants and CO2 capture from fossil fuel combustion. Based on the multicycle calcination-carbonation reaction of CaCO3 for both thermochemical energy storage and post-combustion CO2 capture applications, the operating conditions for each application may involve remarkably different characteristics regarding kinetics, heat transfer and material multicycle activity performance. The novelty and urgency of developing these applications demand an important effort to overcome serious issues, most of them related to gas-solids reactions and material handling. This work reviews the latest results from international research projects including a critical assessment of the technology needed to scale up the process. A set of equipment and methods already proved as well as those requiring further demonstration are discussed. An emphasis is put on critical equipment such as gas-solids reactors for both calcination and carbonation, power block integration, gas and solids conveying systems and auxiliary equipment for both energy storage and CO2 capture CaL applications.

A technical evaluation of CO2 capture technologies when retrofitted to a cement plant is performed. The investigated technologies are the oxyfuel process, the chilled ammonia process, membrane-assisted CO2 liquefaction, and the calcium looping process with tail-end and integrated configurations. For comparison, absorption with monoethanolamine (MEA) is used as reference technology. The focus of the evaluation is on emission abatement, energy performance, and retrofitability. All the investigated technologies perform better than the reference both in terms of emission abatement and energy consumption. The equivalent CO2 avoided are 73–90%, while it is 64% for MEA, considering the average EU-28 electricity mix. The specific primary energy consumption for CO2 avoided is 1.63–4.07 MJ/kg CO2, compared to 7.08 MJ/kg CO2 for MEA. The calcium looping technologies have the highest emission abatement potential, while the oxyfuel process has the best energy performance. When it comes to retrofitability, the post-combustion technologies show significant advantages compared to the oxyfuel and to the integrated calcium looping technologies. Furthermore, the performance of the individual technologies shows strong dependencies on site-specific and plant-specific factors. Therefore, rather than identifying one single best technology, it is emphasized that CO2 capture in the cement industry should be performed with a portfolio of capture technologies, where the preferred choice for each specific plant depends on local factors.

To reduce the overaccumulation of carbon dioxide (CO2) in the atmosphere, direct air CO2 capture (DACC) technologies must (a) satisfy the process requirements for heat and electricity with energy that has few if any CO2 emissions, and (b) physically isolate the CO2 from the atmosphere after its extraction from the air. To isolate the CO2 from the atmosphere at meaningful scale, the CO2 will likely need to be geologically stored in deep saline aquifers. Here we propose to leverage geologic CO2 storage (GCS) in sedimentary basin geothermal resources to produce geothermal heat and electricity for the process energy requirements of solid sorbent DACC. This sedimentary basin CO2-driven geothermal utilization (SB-CO2DGU, also known as CO2 Plume Geothermal) circulates some of the emplaced CO2 to extract geothermal heat in a closed loop between the subsurface reservoir and surface geothermal facility. The proposed integration of DACC and CO2-driven geothermal Utilization and Storage (DACCUS) adds CO2 from the air to this closed loop system that produces renewable energy for use in the DACC process. The strategy first primes the GCS reservoir with CO2 from large point sources, and then integrates CO2 from DACC facility to form the DACCUS system. We focus on the process integration of DACCUS and present a case study of its potential deployment and scaling in the Gulf Coast of the United States. We combine data from prior analyses for a novel investigation of two DACCUS configurations: (1) a DACCUS heat system uses the geothermal heat to regenerate the solid sorbent in the DACC process, and (2) a DACCUS heat and power system uses the electricity generated from the produced geothermal heat for the DACC process. In general, deeper CO2 storage reservoirs (>3.5 km) with higher geothermal temperature gradients (>35 °C km−1), may provide sufficient production wellhead temperatures (>100 °C), and satisfy the electric load in 93% of the combinations of reservoir characteristics we examined.

The mineralization of carbon dioxide offers a way to permanently sequester carbon while producing construction materials, combining the concepts of carbon capture and utilization (CCU) and carbon capture and storage (CSS). However, it is important to evaluate different mineralization processes in terms of their environmental impact. This study provides the first comparative life cycle assessment (LCA) analysis that focuses on the utilization of industrial waste materials. We analyzed the climate and material footprint of six mineralization pathways from cradle to gate using steel slag, concrete waste, municipal solid waste incineration (MSWI) ash, and olivine as feedstock. A sensitivity analysis was used to identify the factors with the greatest impact on environmental performance. Our results show that all processes generate significantly negative values for the global warming impact (GWI) and raw material input (RMI), ranging from −0.6 to −1.3 kgCO2eq.kgfeed−1 and −0.6 to −1.6 kgkgfeed−1, when cement substitute is considered as product. Five out of six processes produce negative values for these factors when sand is considered as a product. When operated as a CCS technology without product use, the processes result in GWI values ranging from −0.13 to 0.01 kgCO2eq.kgfeed−1. Our study confirms that industrial mineralization is a promising technology for reducing carbon dioxide emissions. Future process development should focus on replacing carbon dioxide-intensive products while balancing energy and chemical demand with process efficiency.

This study explores enhancements in CO2 capture and release using monoethanolamine (MEA) combined with iron oxide nanoarticles (IONPs) in a 10 kg per day pilot CO2 capture plant. Previous studies highlighted the potential of nanoparticle additives to improve CO2 capture via modeling and batch experiments; however, robust experimental evidence at the pilot scale is necessary for commercialization. This pilot plant employed a thermal swing process using synthetic CO2–flue gas mixtures, conditioning systems, and Programmable Logic Controller (PLC)-based controls for heating, operation, and data acquisition. IONPs, synthesized through chemical precipitation and characterized by XRD and HR-SEM, were integrated into MEA at concentrations of 0.0001% w/v (1 ppm), 0.001% w/v (10 ppm), and 0.002% w/v (20 ppm). Their electromagnetic properties enhanced mass transfer during absorption and significantly reduced heat demand during stripper desorption. Higher concentrations of IONPs decreased desorption temperatures by up to 7 °C, resulting in estimated energy savings of approximately 10–15%, while achieving CO2 loading rates up to 0.34 mol CO2/mol MEA. Structural stability of the IONPs was confirmed via XRD and HR-SEM analyses following extended thermal cycling. Utilizing a common solvent and abundant catalyst, these demonstrated improvements underscore the practical scalability and commercial viability of MEA-based CO2 capture catalyzed by IONPs, particularly suitable for deployment in large-scale CO2 capture systems in high-CO2-emitting industries.

Fossil-fueled power plants are a major source of carbon dioxide (CO2) emission and the membrane process is a promising technology for CO2 removal and mitigation. This study aims to develop optimal membrane-based carbon capture systems to enhance the sustainability of fossil-fuel power plants by reducing their energy consumption and operating costs. The multi-stage membrane process is numerically modeled using Aspen Custom Modeler based on the solution-diffusion mechanism and then the effects of important operating and design parameters are investigated. Multi-objective process optimization is then carried out by linking Aspen Plus with MATLAB and using an evolutionary technique to determine optimal operating and design conditions. The results show that, as the CO2 concentration in the feed gas increases, the CO2 capture cost significantly decreases and CO2 removal is enhanced, although the process energy demand slightly increases. The best possible trade-offs between objective functions are reported and analyzed, which confirm the considerable potential for improving the sustainability of the process. The CO2 capture cost and energy penalty of the process is as low as 13.1 $/tCO2 and 10% at optimal design and operating conditions. This study provides valuable insight into membrane separation and can be used by decision-makers for the sustainable improvement of fossil-fueled power plants.