Technical and economic study of integrated system of solid oxide fuel cell, palladium membrane reactor, and CO2 sorption enhancement unit

This paper deals with the integrated system of solid oxide fuel cell (SOFC), palladium membrane reactor (PMR), and CO2 sorption enhancement (SE) unit. Three configurations of the SOFC systems fed by biogas are considered, i.e., PMR-SOFC, SE-PMR-SOFC, and SE-PMR-SOFC with a retentate gas recycling (SER-PMR-SOFC). The SOFC system equipped with a conventional reformer (CON-SOFC) is considered as a base case. The simulation results show that the capture of CO2 in biogas before being fed to PMR (SE-PMR-SOFC) can improve H2 recovery. The performance of SE-PMR-SOFC can be further enhanced by recycling retentate gas from PMR to CO2 sorption enhancement unit (SER-PMR-SOFC). Compared to CON-SOFC, both SE-PMR-SOFC and SER-PMR-SOFC give higher power density and thus require smaller stack size (the stack size reduction of 1.55% and 8.27% are observed for SE-PMR-SOFC and SER-PMR-SOFC, respectively). The economic analysis is performed to identify the potential benefits of each SOFC configuration. The results indicate that SE-PMR-SOFC and SER-PMR-SOFC are not cost-effective systems compared with CON-SOFC; however, the capture of CO2 in these SOFC systems offers an environmental benefit. High %total CO2 capture and low cost of CO2 capture are achieved under these SOFC systems.