Effect of Fuel Utilization on Tri-reforming-SOFC Systems with Different Heat Management Strategies

Four tri-reforming-SOFC system configurations are built with different off-gas recirculation methods (anode off-gas recirculation and burner off-gas recirculation) and different reformers (with heat exchange and with oxygen injections) to improve heat management. The systems are modeled to explore the effects of fuel utilization. It is found that the recirculation type mainly affects the maximum temperature in the reformer while the reforming type mainly affects the methane conversion. The max temperature gradient in the stack increases with fuel utilization in configurations C and D, therefore high fuel utilization should be avoided in these two configurations. The system electric efficiencies are enhanced compared with the stack electric efficiency. AOGR and reformer with heat exchange are preferred to enhance the system's electric efficiency, and configuration A exhibits the highest system electric efficiency.