(553f) 1 kWe Diesel Autothermal Reformer Integrated with Catalytic Burner for Exhaust Gas Oxidation

Heavy-duty trucks and recreational vehicles have to idle their engines when extended duration of using energy is required. However, idling causes the environmental issues and performance degradation of vehicles. Auxiliary Power Unit (APU) is a device on a vehicle that provides deficient energy for functions other than propulsion using the fuel from the vehicle. Solid Oxide Fuel Cell (SOFC) based auxiliary power units are expected to be about 15-20% more efficient compared to commercially available diesel based APUs resulting in significantly lower CO₂ footprint and lower emissions of criteria pollutants with low noise. The fuel reforming process, which is integrated with a SOFC for APU application, also plays an important role in an APU system. The synthesis gas consisting mainly of hydrogen, carbon monoxide, water and carbon dioxide generated as a result of hydrocarbon (i.e., diesel) reforming is sent to an SOFC stack for electrochemical oxidation operating at temperatures around 800°C. Moreover, the recent studies have reported a possibility to use SOFC as a CO₂ conversion system. Diesel autothermal reforming (ATR) is used to produce hydrogen-rich gas for SOFC application. 1 kW_e diesel autothermal reforming system is developed and tested for SOFC APU application with consideration of heavy-duty truck integration.

A catalytic burner is integrated into 1 kW_e diesel autothermal reformer to oxidize exhaust gases from the reformer. During the reformer operation including startup process, produced hydrogen and other combustible gases such as carbon monoxide must be fully oxidized before exhaust. Also, heat produced from the burner during the oxidation is utilized into the system to heat up the cathode air supply. In this study, the air supply rate of the catalytic burner is controlled to ensure full oxidation of the exhaust gases. With the burner temperature limitation of 800°C, hydrogen and carbon monoxide are fully oxidized with the catalytic burner. Generated heat is also utilized to increase temperature of cathode input air. As a result, stable startup and operation profile with integration of the catalytic burner can be obtained.