To produce cement clinker by baking of raw meal in a kiln, use is conventionally made of a raw meal preheater in which the heat of the flue gas emerging from the kiln is transferred to the raw meal. In order to remove impurities which accumulate in circulation between the kiln and the raw meal preheater, a part of the flue gas is extracted from the kiln, bypassing the raw meal preheater. The heat generated during the baking of cement clinker can be used particularly efficiently if the flue gases extracted and diverted past the raw meal preheater are used in a boiler to generate hot steam which can subsequently be expanded in a turbine.