Abstract: Waste materials, potentially following their comminution and potentially following their dying or, respectively, preheating, are burned in a cyclone kiln (buring cyclone or, melting cyclone) at extremely high temperatures above 1500.degree. C. with formation of a molten slag low in noxious substances and a hot exhaust gas in which latter the valuable substances and/or noxious substances contained in the waste materials volatilize, whereby dusts enriched with valuable substances on the one hand and, on the other hand, dusts enriched with noxious substances are respectively separately separated out of the exhaust gas by partial condensation.

Abstract: A method and apparatus for reducing the sulfur content and/or the SO.sub.2 emission in a system for calcining fine grained materials such as in the manufacture of cement utilizing a pre-calcining and a final calcining stage. The sulfur content of a process gas or of a material stream is determined and then is mixed with appropriate amounts of a dust or a raw meal in a reaction zone, the dust or raw meal containing sulfur bonding substances such as alkaline earth carbonates. The exhaust gas from which the sulfur compounds are removed by the sulfur bonding is separated from the sulfur containing solids and the exhaust gas and solids are removed from the calcining system.

Abstract: Method and apparatus for the thermal treatment of moist, granular materials utilizing at least two superposed cyclone separators, with a relatively long gas conduit connecting the lower cyclone separator to the upper one. Charging means are provided in the conduit for introducing material to be treated near the lower cyclone separator, and a venturi-type constriction is provided in the conduit below the charging means, the constriction having its lower end projecting into the lower cyclone separator and serving to break up lumps of material which might otherwise be deposited in the cyclone separator and transfer the particulate material to the upper cyclone separator.

Abstract: The invention relates to a method and apparatus for the production of commercially utilizable, homogeneous raw meal-like mixtures from fine grained, moist materials, particularly from sludges, slimes, slurries, etc., and additives.

Abstract: Method and apparatus for the thermal treatment of moist raw pulverulent material, particularly slurries of raw cement material, wherein a plurality of gas and material separators are connected in series, the material to be treated is introduced between the last separator and the next-to-the-last separator and penetration of infiltrated air into the gas stream is prevented by a blower in advance of the zone of introduction of the raw material.The blower prevents a large pressure differential at the point of material supply and at the same time accommodates maintenance of a high vacuum and rate of flow of gas for the transporting of the material. The gas conduit leading to the last separator has an elongated riser so that the moist material introduced into the gas stream is maintained in contact with the hot gases for a long period to effect efficient pre-drying of the material.