Abstract: The invention relates to the production and use of a water-repellent and impregnating product for surfaces of building materials. In order to be able to waterproof and impregnate building material surfaces in a relatively simple, economical and yet very reliable and durable manner, a coating product is proposed which is produced from two aqueous solutions and forms an aqueous solution product which contains silicon, calcium and sodium ions, wherein the capacity for dissolving the calcium oxide is increased by a dissolving agent added to the water and the finished product, after application and drying on the building material surface, forms a glass-like surface film.

Abstract: Cement clinker is produced using high sulfur fuels by combusting high sulfur fuel within a kiln. The feed material is introduced at an inlet of preheater of the kiln and is sintered by the combusting fuel to form sintered material. The sintered material is cooled to form cement clinker. The production of the sintered material is controlled by measuring the sulfur content in the cement clinker and using that measurement to control the concentration of oxygen at the reaction and sintering zone of the kiln.

Abstract: A surface of solid building material may be waterproofed and impregnated against chemical and biological corrosion by forming first and second aqueous solutions one of which contains calcium ions and the other of which contains sodium and silica ions. The two solutions may be mixed and applied simultaneously to the surface or the two solutions may be applied to the surface sequentially, the solution containing the sodium and silica ions being applied first. In either case there is formed on the building material surface a hard, glass-like transparent coating of sodium calcium silicate.

Abstract: Cement clinker is produced from powdered and fine-grained raw material by the use of a vertical stage cyclone preheater, a precalcinator, a kiln, and a cooler. The raw material is preheated by exhaust gases from the kiln and the cooler. Dust is filtered out of the exhaust gases, preheated, precalcined, and then burnt to cement clinker in a kiln. Downstream of the first preheater stage a relatively smaller part-quantity of the material is branched off and fed as a mixture jointly with the dust from the filter to the upper end of the precalcinator. This mixture passes through the precalcinator from top to bottom co-current with combustion air and with fuel for precalcination and then is delivered to the kiln inlet.

Abstract: The invention is related to a method and an apparatus for producing cement clinker, in which the cement clinker is first of all burnt in a burning zone and then cooled in a cooling zone, wherein the cooling takes place at least partially by the delivery of fuel and steam, characterised in that in a first cooling phase the delivered fuel is mixed with the cement clinker and initially pyrolysed and the resulting pyrolysis products have a strong endothermic reaction with the steam, so that the cement clinker is quenched in such a way that at least 95%, preferably all, of the liquid phase contained therein is transformed into glass.

Abstract: Apparatus and method for drying and grinding moist raw cement or other material wherein the moist material is introduced to a grinding zone at which it is ground to produce relatively fine and relatively coarse particles which are separated and delivered to separate outlets. Hot drying gas is delivered to the path of fresh material flowing to the grinding zone to pre-dry such material, and the ground particles flowing to the respective discharge outlets are further dried by hot gas. The further dried relatively coarse particles are delivered the fresh material inlet and mixed with fresh material therein.