Simulation and Economic Investigation of CO2 Separation from Gas Turbine Exhaust Gas by Molten Carbonate Fuel Cell with Exhaust Gas Recirculation and Selective Exhaust Gas Recirculation

Abstract

The paper presents a simulation investigation of using a molten carbonate fuel cell (MCFC) combined with exhaust gas recirculation (EGR) or selective exhaust gas recirculation (SEGR) to reduce CO2 emission from the gas turbine in order to cope with climate change problem. EGR or SEGR can be used to concentrate the low-concentration CO2 in gas turbine exhausts. The CO2 concentration is then raised further by adding gas turbine exhaust to the MCFC’s cathode. The suggested gas–steam combined cycle system paired with MCFC and CO2 collection without EGR is contrasted with two novel gas–steam combined cycle systems integrated with MCFC, EGR, or SEGR with CO2 capture (the reference system). The thermal efficiency of the gas–steam combined cycle systems’ integrated MCFC, EGR and SEGR with CO2 collection is 56.08%, which is 1.3% higher than the reference system. The cost of CO2 avoided in the new system with SEGR will be equal to that of the system with the MEA technique for CO2 capture if the MCFC cost is reduced to 904.4 USD/m2.