Cycle analysis of low and high H2 utilization SOFC/gas turbine combined cycle for CO2 recovery

Abstract A major factor in global warming is CO 2 emission from thermal power plants, which burn fossil fuels. One technology proposed to prevent global warming is CO 2 recovery from combustion flue gas and the sequestration of CO 2 underground or near the ocean bed. Solid oxide fuel cell (SOFC) can produce highly concentrated CO 2 , because the reformed fuel gas reacts with oxygen electrochemically without being mixed with air in the SOFC. We therefore propose to operate multi-staged SOFCs with high utilization of reformed fuel to obtain highly concentrated CO 2 . In this study, we estimated the performance of multi-staged SOFCs considering H 2 diffusion and the combined cycle efficiency of a multi-staged SOFC/gas turbine/CO 2 recovery power plant. The power generation efficiency of our CO 2 recovery combined cycle is 68.5%, whereas the efficiency of a conventional SOFC/GT cycle with the CO 2 recovery amine process is 57.8%.