Abstract: The present invention relates to a self-leveling composition for floor toppings, characterized in that it is based on Portland cement or on cement mix CM II or CM III, and in that it further comprises at least sand, water and at least one plasticizer which is a water-soluble or water-dispersible organic compound (I) containing at least one aminodi(alkylenephosphonic) group and at least one polyoxyalkyl chain, or at least one salt of compound (I).

Abstract: A process and apparatus for manufacturing cement clinker in which pellets of raw material containing the necessary components for manufacturing the clinker are introduced into an apparatus where the pellets flow under gravity, successively through a preheating zone, a clinkering zone using a fluidized bed and a cooling zone. The pellets contain an amount of comminuted carbon determined so that its combustion produces an amount of heat within each pellet sufficient to carry out decarbonation of the material, taking into account the heat introduced by the hot gases passing upwardly through the apparatus. Decarbonation is completed at the base of the preheating zone and the pellets enter the clinkering zone at a temperature which is close to the clinkering temperature. Additional heat is supplied through burners within the clinkering zone.

Abstract: This material is an anorthite with an alumina skeleton of which the overall porosity is between 40 and 70% with a pore size such that the average diameter is between 0.75.mu. and 8.mu..To obtain it, water is mixed with a mixture of aluminous and sillicoaluminous materials with at least 10% by weight of calcium sulphate, it is dried and calcined at 1000.degree. to 1400.degree. C. The starting materials are selected so that the final product essentially comprises CaO, SiO.sub.2 and Al.sub.2 O.sub.3 with, by an SiO.sub.2 /Al.sub.2 O.sub.3 weight ratio less than 2 and a CaO/Al.sub.2 O.sub.3 weight ratio less than 1. A preferred composition corresponds to point D of the diagram.Application to replace plaster in the manufacture of moulds for the sanitary industry.

Abstract: A hydrated mineral charge is manufactured by grinding a composition selected from the group consisting of calcium aluminates, aluminous cements, and Portland cements, to a powder having an average fineness of from about 3,000 to about 5,000 square centimeters per gram (Blaine's specific surface), hydrating the composition with water to form a paste at a temperature from about 10.degree. C to about 100.degree. C, and adding a sufficient quantity of a liquefying surface active agent to the paste so that its viscosity is less than about 5,000 cps, and so that the paste has a solid content from about 60 percent to about 80 percent by weight.

Abstract: A process includes hydrating between about 10.degree. and 100.degree. C, one of the synthesized anhydrous calcium aluminates prepared specially or stemming from the manufacture of hydraulic binders or of anhydrous calcium silicates, groundup to an average degree of fineness, with a quantity of water of such an order of magnitude that a paste is formed, having dry extracts between about 5 and 70% by weight; subjecting at least the large particles to a vigorous agitation during the hydration to form a suspension, drying the formed suspension to a dry powder and collecting the obtained dry powder.

Abstract: Raw material for making cement is treated in an installation comprising a plurality of superimposed cyclones constituting a multi-stage exchanger wherein the solid raw material and gases issuing from a clinkerization furnace circulate counter-currently, and wherein at least a portion of the raw material issuing from the penultimate exchanger stage is injected into the gas current produced by the furnace. The raw material is injected in the form of a "curtain", or "screen", into an upstream section of the furnace. This novel method and the novel device for carrying out said method allow the building-up of deposits upstream of the furnace to be eliminated.

Abstract: A substantially stoichiometric mixture of calcic aluminate and calcium sulphate, as white as possible, formed at a temperature in the range of about 20.degree. to 90.degree. C, is hydrated simultaneously; water is added at least in stoichiometric proportions for the reaction and at a maximum in an amount such that after the reaction a product is obtained containing 5% (dry) ettringite and 95% (by weight) water, stoichiometry being defined, for example by the reactionCaO,Al.sub.2 O.sub.3 + (CaO, H.sub.2 O) + 3(CaSO.sub.4, 2H.sub.2 O) + 24 H.sub.2 O.fwdarw.(CaO).sub.3, Al.sub.2 O.sub.3, 3 CaSO.sub.4, 32 H.sub.2 O (ettringite)It is thus possible to obtain in an economical and very flexible manner, ettringite, or suspensions containing same, for all industrial uses, notably for paper-making.