Abstract: The invention relates to a method and apparatus for producing burnt material and for generating electrical energy, in which the material is burnt using lower-grade fuel in a rotary kiln by means of hot kiln exhaust gases and at least a proportion of the quantity of heat contained in the exhaust gases from the rotary kiln is converted into electrical energy, the temperature of these kiln exhaust gases being between 700.degree. and 1200.degree. C., preferably between 800.degree. and 900.degree. C.

Abstract: The invention relates to apparatus for delivering material to part of a plant, for example to a crushing and grinding machine, in which the fines are separated out of the feed material passing through the material feed chamber by means of an air stream. In this way a substantial increase in the output of the part of the plant can be achieved.

Abstract: A process for the heat-treatment of fine-grained material which is preheated in a cyclone preheater, deacidified by additional fuel in a precalcination zone, and subsequently calcined to completion in a revolving tubular kiln. The gas temperature in the cyclone preheater and the material temperature after passage through the precalcination zone are measured, the difference between these temperatures is determined and, when the temperature difference reaches a maximum or minimum value, regulation of the fuel supply to the precalcination zone is switched to manual operation. In this way, the amount of fuel is rapidly adapted to the particular circumstances prevailing in the event of disturbances.