Study on CO2 capture from molten carbonate fuel cell hybrid system integrated with oxygen ion transfer membrane

Abstract

Based on the benchmark MCFC (molten carbonate fuel cell) hybrid system without CO2 capture, a novel ITM (oxygen ion transfer membrane)-integrated MCFC hybrid system with CO2 capture is proposed, which uses ITM to produce the needed oxygen for the oxy-fuel combustion in the afterburner. With the Aspen plus software, the system model is established and then the system performance is investigated. In addition, the sensitivity analysis of the key parameters and the exergy analysis of the overall new system are also studied. Results show the efficiency of the benchmark hybrid system without CO2 capture is 63.36%, in comparison when capturing 85% of the CO2 emissions, the efficiency of the system integrated with the cryogenic air separation unit is 60.94%, 2.42% lower than that of the benchmark system, while capturing the same amount of CO2 emissions, the efficiency of the new system integrated with ITM is 62.68%, only 0.68% lower than that of the benchmark system, in addition the specific energy consumption of capturing per mole CO2 (SPECCA) of the new system is nearly a quarter of the system integrated with the cryogenic air separation unit. Achievements from this paper will provide valuable references for capturing CO2 from MCFC power plants with lower energy consumption.