Abstract: A method of producing a hot gas flow by combustion of preferably liquid fuels, by the following steps:(a) atomizing the liquid fuel to form fine particles;(b) further atomizing the thus generated fuel particles with the aid of combustion air supplied as atomizing medium, and reducing the mean fuel particle diameter to less than one-half of the mean diameter obtained in step (a);(c) burning the fuel-air mixture within a flame cone extending on an axis A, under stoichiometric conditions or with an excess of oxygen within an air duct;(d) introducing a stream of cold air to be heated or of another medium, optionally including components adapted to be oxidized, in a plane E extending substantially perpendicularly to axis A.Further, the invention relates to a hot gas generator or incinerator for carrying out the method, comprising a straight air conducting pipe which has coaxially positioned therein a burner for liquid fuels, including a two-stage atomizing assembly for the liquid fuel.