Development of a self-sustaining kWe-class integrated diesel fuel processing system for solid oxide fuel cells

Among high temperature fuel cells, solid oxide fuel cells (SOFCs) possess several advantages such as fuel flexibility, high power density, and high-quality waste heat for cogeneration applications. However, if the reformates of hydrocarbon fuel are used to operate SOFCs, sulfur poisoning and carbon deposition is observed. Diesel reformate contains sulfur compounds and residual low-molecular-weight (LMW) hydrocarbons, which are formed on the anode of the SOFC. In this study, a new type of diesel fuel processing system was introduced for the stable operation of SOFCs. The novel diesel fuel processor contains three different reaction stages: autothermal reforming (ATR), adsorptive desulfurization, and post-reforming. For the stable operationfof SOFCs, the desulfurization and post-reforming processes are used to eliminate sulfur compounds and residual light hydrocarbons from the diesel reformate. The proposed fuel processor does not require an additional heat exchanger or electrical equipment for the supply of heat or the vaporization of fuel and water. The integrated reactor can be implemented as a self-sustaining reactor due to the exothermic nature of the ATR reaction. The reaction temperature of desulfurization and post-reforming processes are controlled by the arrangement of the reactors and heat exchange through the integrated reactor. The kWe self-sustaining integrated diesel fuel processor was operated for approximately 1000 h, and a reforming efficiency of 60% was achieved. Moreover, the desulfurizer and post-reforming reactor completely removed H2S and light hydrocarbons from the diesel reformate.