Abstract: A heating assembly and a method for burning fuel of organic origin, includes a substantially enclosed hollow assembly including a predetermined region within the assembly for receiving the fuel for ignition purposes, a first oxygen supply device for supplying the predetermined region with oxygen at least at a rate adequate for producing a gas flow of distilled-off gases, air gases and combustion gases from the ignited fuel, an elongated outer shell disposed within the predetermined region and having a plurality of passages for dividing the gas flow into a plurality of streamlets, an elongated inner shell, having an inlet and an outlet, disposed within the outer shell and defining a space between the inner and outer shells, the space communicating with the inlet, the streamlets being recombined into a gas stream in the space, a second oxygen supply device for supplying the inner shell with oxygen near its inlet for burning the stream of gas; and an exhaust conduit communicating with the outlet for exhausting t