Substoichiometric combustion of low heating value gases

A method for the recovery of energy from a gas stream having an average heating value in the range of about 15 to about 200 Btu/scf and having a combustible component comprising one or more hydrocarbons having from one to about seven carbon atoms, carbon monoxide or mixtures thereof and up to about 50 mol percent hydrogen, which comprises the steps analyzing said gas stream for the presence of arsine, adjusting the quantity of arsine in said gas stream as necessary to provide an amount between about 0.1 ppm and about 50 ppm arsine, passing said gas stream admixed with air for combustion at an average air equivalence ratio of between about 0.2 and about 0.95 in contact with an oxidation catalyst in at least one combustion zone at a temperature high enough to initiate and maintain combustion of said gas stream, and utilizing the heat energy produced in said gas stream by said combustion.