Catalytic combustion of methane in a fluidized bed reactor under fuel-lean conditions

Fluidized-bed combustion of premixed lean methane-air mixtures over a copper-based catalyst (1-mm diameter) has been tested. Combustion experiments have been performed in a 100-mm externally heated fluidized-bed reactor. Effects of methane inlet concentration, gas superficial velocity, and bed height on reactor performance have been evaluated. 100% combustion efficiency could be achieved at suitable gas space-time values and no permanent bypass of methane in the bubble phase onsets under the experimental conditions tested, indicating efficient interphase mass transfer mechanisms between bubbles and emulsion phase. Kinetic parameters of the heterogeneous catalytic combustion have been determined by analyzing experimental results in the light of a simple theoretical framework.