Study on a gas-steam combined cycle system with CO2 capture by integrating molten carbonate fuel cell

• A new combined cycle system with CO2 capture by integrating MCFC is proposed.
• The exergy loss distribution rules of new system are revealed.
• The effects of key parameters on the system performances are investigated.
• The economic performance of new system is evaluated.
• The new system still has a high efficiency after CO2 capture.

This paper studies a gas-steam combined cycle system with CO2 capture by integrating the MCFC (molten carbonate fuel cell). With the Aspen plus software, this paper builds the model of the overall MCFC-GT hybrid system with CO2 capture and analyzes the effects of the key parameters on the performances of the overall system. The result shows that compared with the gas-steam combined cycle system without CO2 capture, the efficiency of the new system with CO2 capture does not decrease obviously and keeps the same efficiency with the original gas steam combined cycle system when the carbon capture percentage is 45%. When the carbon capture percentage reaches up to 85%, the efficiency of the new system is about 54.96%, only 0.67 percent points lower than that of the original gas-steam combined cycle system. The results show that the new system has an obvious superiority of thermal performance. However, its technical economic performance needs be improved with the technical development of MCFC and ITM (oxygen ion transfer membrane). Achievements from this paper will provide the useful reference for CO2 capture with lower energy consumption from the traditional power generation system.