Carbon dioxide (CO₂) is the single largest contributor to climate change due to its increased emissions since global industrialization began. Carbon Capture, Storage, and Utilization (CCSU) is regarded as a promising strategy to mitigate climate change, reducing the atmospheric concentration of CO₂ from power and industrial activities. Post-combustion carbon capture (PCC) is necessary to implement CCSU into existing facilities without changing the combustion block. In this study, the recent research on various PCC technologies is discussed, along with the membrane technology for PCC, emphasizing the different types of membranes and their gas separation performances. Additionally, an overall comparison of membrane separation technology with respect to other PCC methods is implemented based on six different key parameters—CO₂ purity and recovery, technological maturity, scalability, environmental concerns, and capital and operational expenditures. In general, membrane separation is found to be the most competitive technique in conventional absorption as long as the highly-performed membrane materials and the technology itself reach the full commercialization stage. Recent updates on the main characteristics of different flue gas streams and the Technology Readiness Levels (TRL) of each PCC technology are also provided with a brief discussion of their latest progresses.

As natural gas-fired combined cycle (NGCC) power plants continue to constitute a crucial part of the global energy landscape, their carbon dioxide (CO₂) emissions pose a significant challenge to climate goals. This paper evaluates the feasibility of implementing post-combustion carbon capture, storage, and utilization (CCSU) technologies in NGCC power plants for end-of-pipe decarbonization in Uzbekistan. This study simulates and models a 450 MW NGCC power plant block, a first-generation, technically proven solvent—MEA-based CO₂ absorption plant—and CO₂ compression and pipeline transportation to nearby oil reservoirs to evaluate the technical, economic, and environmental aspects of CCSU integration. Parametric sensitivity analysis is employed to minimize energy consumption in the regeneration process. The economic analysis evaluates the levelized cost of electricity (LCOE) on the basis of capital expenses (CAPEX) and operational expenses (OPEX). The results indicate that CCSU integration can significantly reduce CO₂ emissions by more than 1.05 million tonnes annually at a 90% capture rate, although it impacts plant efficiency, which decreases from 55.8% to 46.8% because of the significant amount of low-pressure steam extraction for solvent regeneration at 3.97 GJ/tonne CO₂ and multi-stage CO₂ compression for pipeline transportation and subsequent storage. Moreover, the CO₂ capture, compression, and transportation costs are almost 61 USD per tonne, with an equivalent LCOE increase of approximately 45% from the base case. This paper concludes that while CCSU integration offers a promising path for the decarbonization of NGCC plants in Uzbekistan in the near- and mid-term, its implementation requires massive investments due to the large scale of these plants.

Reaching net-zero emissions by the middle of this century requires the implementation of massive carbon dioxide (CO₂) emission reduction strategies along with the reduction of other greenhouse gases on both global and country scales. Thus, carbon capture, storage, and utilization (CCSU) is a promising technology in combination with renewable energy transition. Currently, CO₂ utilization has attracted much attention from the scientific community worldwide, since it can improve the economic viability of CCSU deployment by creating a market for the recovered CO₂ stream. In this study, a brief assessment and comparison of potential CO₂ utilization pathways in Uzbekistan, including CO₂-to-chemical/fuel conversion, CO₂ bio-fixation/mineralization, and the direct use of CO₂, such as for enhanced hydrocarbon recovery (EHR), are conducted considering the CO₂ stationary sources and site-specific conditions of the country. In addition, possible challenges and opportunities for large-scale CO₂ utilization routes are also discussed. According to this assessment, there is great potential for the direct use of CO₂ as a process-boosting agent for EHR in more than 22 major natural gas, crude oil, and coal reservoirs. Moreover, methanol and urea production processes can also create huge market demand for recovered CO₂ as long as the conventional CO₂ production processes are replaced by sustainable ones.

Cement production is one of the key industries responsible for emissions of greenhouse gases, especially carbon dioxide (CO₂), which influence climate change. In order to reach zero carbon in the cement industry, various deep decarbonization pathways involving carbon capture, storage, and utilization (CCSU), using low-carbon material and fuel, optimal process control, and waste heat utilization techniques must be implemented. As for the example of Uzbekistan, approximately 30 facilities generate more than 15 Mt of cement annually and are responsible for 11.3% of the country’s total CO₂ emissions. In this study, decarbonization pathways for cement plants in Uzbekistan, including CCSU, the use of alternative fuels, electrification, and waste heat integration techniques, are compared based on existing challenges and opportunities. The availability of alternative fuel and material resources suitable for the total production capacity, the comparison of post-combustion, pre-combustion, and oxyfuel combustion CCSU methods for the cement plant, and the use of energy-efficient technologies are discussed.