A self-built low concentration combustible waste gas processing system was applied to perform experiments on heat recovery characteristics.The mixture of natural gas and compressed air was used.The effects of such factors as initial temperature

water flow rate

cycle time

feed gas concentration

space velocity and catalysts on combustion efficiency and heat recovery effectiveness were studied.The results show that

the proposed system was capable of keeping the effectiveness of heat recovery higher than 50% under the condition of stable self-sustained combustion efficiency over 90%.The optimization of operating parameters combination improved the temperature profiles' symmetry for the cyclic steady state of system and increased the combustion efficiency and heat recovery effectiveness of combustion.Moreover

it was found that the effects of catalytic characteristic

thermophysical properties of catalyst cannot be neglected for the low concentration combustible waste gas processing system.