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The sudden increase in the concentration of carbon dioxide (CO2) in the atmosphere due to the high dependency on fossil products has created the need for an urgent solution to mitigate this challenge. Global warming, which is a direct result of excessive CO2 emissions into the atmosphere, is one major issue that the world is trying to curb, especially in the 21st Century where most energy generation mediums operate using fossil products. This investigation considered a number of materials ideal for the capturing of CO2 in the post-combustion process. The application of aqueous ammonia, amine solutions, ionic liquids, and activated carbons is thoroughly discussed. Notable challenges are impeding their advancement, which are clearly expatiated in the report. Some merits and demerits of these technologies are also presented. Future research directions for each of these technologies are also analyzed and explained in detail. Furthermore, the impact of post-combustion CO2 capture on the circular economy is also presented.

This paper presents the findings of the techno-economic assessment undertaken by Wood for the UK Government Department for Business, Energy and Industrial Strategy on the large-scale deployment of Molten Carbonate Fuel Cells (MCFCs) for post-combustion CO2 capture integrated with a new build combined cycle gas turbine power plant for the generation of low carbon electricity. The findings are compared with a state of the art proprietary amine scrubbing technology. Based on a new build power plant to be installed in the North East of England, with a power train comprising two trains of H-class gas turbines each with a dedicated steam turbine, the configuration presented utilises MCFCs between the gas turbine exhausts and their heat recovery steam generators and cryogenic separation for unconverted fuel recycle and CO2 purification. It was found that the proposed configuration could achieve 92% CO2 capture from the overall power plant with MCFCs while achieving 42% of additional new power production with only 2.6 %-points of thermal efficiency penalty compared to a conventional proprietary amine benchmark. While the total project capital cost increased by 65%, the high overall thermal efficiency and additional power generated resulted in a Levelised Cost of Electricity almost identical to the benchmark at £70/MWh (US$97/MWh). A number of areas are identified for potential further improvement in this scheme. It is concluded that use of MCFC technology, which also has the capability to be tailored for hydrogen production and combined heat and power services, shows significant potential to be competitive with, or exceed, the cost and technical performance of current state of the art technologies for post-combustion CO2 capture.

Heavy industries including cement, iron and steel, oil refining, and petrochemicals are collectively responsible for about 22% of global CO2 emissions. Among these industries, oil refineries account for 4–6%, of which typically 25–35% arise from the regenerators in Fluid Catalytic Cracking (FCC) units. This article reviews the progress in applying CO2 capture technologies to FCC units. Post combustion and oxyfuel combustion have been investigated to mitigate CO2 emissions in FCC and, more recently, Chemical Looping Combustion (CLC) has received attention. Post combustion capture can readily be deployed to the flue gas in FCC units and oxyfuel combustion, which requires air separation has been investigated in a pilot-scale unit by Petrobras (Brazil). However, in comparison, CLC offers considerably lower energy penalties. The applicability of CLC for FCC has also been experimentally investigated at a lab-scale. As a result, the studies demonstrated highly promising CO2 capture capacities for FCC with the application of post combustion (85–90%), oxyfuel combustion (90–100%) and CLC (90–96%). Therefore, the method having lowest energy penalty and CO2 avoided cost is highly important for the next generation of FCC units to optimize CO2 capture. The energy penalty was calculated as 3.1–4.2 GJ/t CO2 with an avoiding cost of 75–110 €/t CO2 for the application of post combustion capture to FCC. However, the application of oxyfuel combustion provided lower energy penalty of 1.8–2.5 GJ/t CO2, and lower CO2 avoided cost of 55–85 €/t CO2. More recently, lab-scale experiments demonstrated that the application of CLC to FCC demonstrate significant progress with an indicative much lower energy penalty of ca. 0.2 GJ/t CO2.