Catalytic Combustion of Ultra-Low Heating Value Fuels Over 0.5%Pd/ZrO₂/γ-Al₂O₃ Catalyst

Catalytic combustion of ultra-low heat value fuel over 0.5%Pd/ZrO₂/γ-Al₂O₃ was investigated to offer an opportunity for scientifically using such fuel sources. The experimental studies were performed using single fuel, synthetic mixtures and different kinds of gasified biomasses, respectively. The effects of varied combustible gas concentration, inlet temperature and flow velocity on the conversion rate were also studied. The results showed that the ignition temperature of 1.4% CH₄ over the catalyst used is lower 210 °C than that in the oxidation absence of catalyst. Conversion of CH₄ increased with decreasing flow velocity and increasing combustible gas concentration. The influence of the flow velocity on the conversation is more significant when further increasing the CH₄ concentration to a certain degree. The ignition temperature for CO, H₂, CH₄ decreased with increasing concentration, and the specific order is T_CH4, T_CO, T_H2. The experimental data showed that the influence of H₂ is very obvious for CH₄ combustion-supporting character by adding different concentration of H₂. Among the experiments of three kinds of gasified biomasses, the catalytic combustion characteristics of wood chip gas is best, followed by grape seed gas and cotton wood gas. These studies would provide the experimental analysis and technical support for catalytic combustion technology application in ultra-low heat value fuel.