Abstract: A process of manufacturing a sulfoaluminate or ferroaluminate cement, and an apparatus for the manufacture. The cement is manufactured from a mixture containing CaCO3, Al3 and/or Al(OH)3, CaSO4, SiO2 and/or a product containing silica or silicates such as clay, these compounds being present in the anhydrous or hydrated form. In this process, the mixture is treated up to clinkering by movement in a center of a kiln, in a sheet with approximately constant thickness, at approximately constant speed, along a treatment path having a positive temperature gradient, and for a treatment time during which the mixture remains below its melting temperature. The mixture is clinkered to produce a clinkered mixture that is cooled upon exit from the treatment path.

Abstract: Manufacturing process of a sulfoaluminate or ferroaluminate cement, cement obtained by this process, and installation for implementation. The invention concerns a manufacturing process of cement (1) from a mixture (2) containing CaCO3, Al2O3 and/or Al(OH)3, CaSO4, SiO2 and/or a product containing silica or silicates such as clay, these compounds being present in the anhydrous or hydrated form, individually or in combination.

Abstract: The method comprises the steps of: preparing a belitic crude cement, neutralizing waste sulfurous acids by means of at least clay-calcareous fines which are thus transformed into artificial gypsum, and adding said artificial gypsum to the belitic crude cement.

Abstract: The method for producing mineral products having a great heat content from waste materials and slurries and resulting products comprises the steps of: submitting the waste materials and slurries to a homogenizing mixing; making a stoichiometric mixture at least of CaCO.sub.3, clay and SiO.sub.2 ; circulating the stoichiometric mixture in at least one heating and calcinating furnace whereby a lime product is produced at a temperature for decarbonating CaCO.sub.3 ; separating at least in part the lime product; and raising the temperature at least until obtainment of (CaO).sub.2 (SiO.sub.2).beta. having hydraulic properties and a crystallised form wherein .beta. is belite.