Abstract: A method of and an apparatus for the thermal degradation of refuse, garbage and other waste material in which the waste material stream is reacted with air or oxygen in a reaction chamber for pyrolysis, destructive distillation or incineration of the waste material. The released thermal energy, spatial temperature distribution or outlet gas temperature is measured and used to control a feeder which supplies particles of a supplemental fuel, itself recovered from a waste material separate from the waste material stream, to the reaction chamber.