A rotary kiln with primary-air introduction on the end wall of the rotary tube is characterised in that at least two primary-air nozzles are directed in relation to one another and to the fuel bed in such a manner that two swirls running in opposite directions are created in the rotary tube, the axes of rotation of which run essentially parallel to the axis of the rotary tube and which rotate about these axes of rotation in such a manner that they support the thermal-induced movement of the combustion gases.
