Abstract
The Catalytic combustion of a lean premixed propane mixture was investigated below the catalyst temperature of 650°C and without gas-phase reaction, using a platinum-impregnated foam catalyst. The temperature distribution in the catalyst plate and the composition of the exhaust gas were measured at air ratios of about 2.2 to 5.8 and heat loads 43kW/m2 to 115 kW/m2 under stable combustion conditions. Since the maximum temperature was observed very near the inlet of the catalyst plate, it is thought that the reaction rate of the catalyst is high and the reaction zone is narrow. When the air ratio was decreased while keeping the heat load constant, the maximum temperature in the catalyst plate increased, but the outlet surface temperature of the catalyst plate was almost constant. The temperature distribution of the outlet surface of the catalyst plate was influenced by natural convection and showed higher temperature in the upper region. The combustion efficiency was strongly related with the catalyst temperature and showed almost the same value when the maximum temperatures are the same. The range of stable catalytic combustion was investigated and its relation to the catalyst thickness was determined.
