Designing and analysis of SOFC operating with syngas and coal gasification integrated system

Solid oxide fuel cells (SOFCs) are electrochemical conversion devices transforming chemical energy of fuel into electric current with high efficiency. SOFCs are composed of three main parts: anode, cathode, and electrolyte. High operating temperature provides fuel flexibility to SOFCs due to employing oxide ions as charge carrier. Even though, high operating temperature of SOFCs causes material and fabrication restrictions, it enables the utilization of coal syngas as fuel. Internal reforming of methane could be achieved in the anode compartment of SOFC due to the high operating temperature. In this study the SOFC operating with syngas and coal gasification integrated system is designed and developed to investigate the effects of fuel concentration on the SOFCs' performance. Different fuel concentrations of H2 and CH4 are fed to SOFC test rig and fuel monitoring system employing mid-IR absorption spectroscopy. Electrochemical performance characterization and $in-situ$ SOFC exhaust analysis conclude that H2 has a better fuel performance than CH4 with respect to open circuit voltage (OCV) and power output values. Furthermore, CH4 is promising for the integration of coal gasification system with a solid oxide fuel cell (SOFC) for clean coal utilization. The fuel conversion efficieny of SOFC system operating at 500 mV anodic overpotential with the fuel of 50 sccm CH4 is calculated as 18.57 \%.