Abstract: In a process for utilizing organic waste materials, in particular cellulose-containing, moist, organic waste materials, in a clinker production process in which the waste materials are introduced as fuel and burnt in the clinker production process, the waste materials are brought into contact with the hot exhaust gases of the clinker production process and dried in a drying step flowing in parallel therewith before they are introduced into the clinker production process. The drying step is carried out in a drying reactor in which the moist waste materials are passed together with the hot exhaust gases through a series of concentrically arranged tubes, with multiple changes in flow direction about 180°, and the temperature of the hot exhaust gases is set to a maximum value of 400° C. by mixing in of ambient air and/or air from the clinker production process before the drying step.

Abstract: A process for reducing the set time a plaster slurry. The process comprises the steps of, providing a pre-determined amount of water, providing a pre-determined amount of the plaster, mixing the water and the plaster together at a first time to form a slurry, and, re-directing a portion of the slurry formed at the first time to combine with slurry formed at a second time.

Abstract: An exemplary method of the invention comprises introducing into a grinding mill, wherein cement clinker is ground to provide cement powder, a diamine such as tetrahydroxylethylethylene diamine, and an alkanolamine such as triethanolamine or triisopropanolamine. The combination of the diamine and alkanolamine provides superior grinding efficiency compared to diamine or alkanolamine added separately.

Abstract: In order to make sure, for cement clinker production lines with blown injection of dispersible solid fuels such as, for example, coal dust, into the calcinator which is provided with fuel, that an open flame does not occur at the fuel injection point, it is proposed according to the invention that the fuel is fed into a meal intake box that has a sloping raw meal chute and deflector slide and is arranged on the outside of the calcinator and connected to it through a wall opening and the fuel is pre-mixed with the pre-heated raw meal there, and then introduced via the deflector slide into the reaction section of the calcinator in order to form a gas-raw meal-solid fuel-suspension that is uniformly distributed.

Abstract: A process is disclosed for producing cement clinker, comprising the steps of: a) providing a mixture of ground calcareous materials and ground argillaceous materials; b) heating the mixture of step a) to a temperature sufficient to calcine and fuse the ground materials to form the cement clinker, and thereby producing an exhaust gas containing CO2; c) catalysing the hydration of at least a portion of the CO2 contained in the exhaust gas and producing a solution containing bicarbonate ions and hydrogen ions; and d) adding to the solution obtained in step c) metal ions, and adjusting the pH of the solution to precipitate a carbonate or said metal. Preferably, the metal ions are Ca++ obtained from the dissolution of a material selected from the group consisting of CaCl2, cement kiln dust and sea salts and the carbonate is CaCO3 which is advantageously recycled into the process by adding the CaCO3 to the mixture of step a). A cement plant for performing this process is also disclosed.

Abstract: A decorative aggregate-containing cementitious slurry having decorative aggregate and cementitious matrix composition forms a monolithic structure when effectively applied to a freshly poured cementitious base and simultaneously cured therewith. The slurry and the base are cured for a time sufficient for producing the monolithic structure with a decorative aggregate-containing cementitious surface. The slurry produces a decorative aggregate-containing cementitious layer having a cured thickness effective for permanently securing the decorative aggregate therein with a portion of the decorative aggregate exposed. Various decorative surfaces are produced without requiring expensive hand broadcasting of the decorative aggregate, and without expensive surface grinding. Dry components of the slurry are decorative aggregate and decorative cementitious matrix blend.

Abstract: A process for the preparation of a copolymer comprises reacting in an aqueous medium at a temperature of from 25° C. to 100° C. in the presence of from 1.0-25 weight percent based on the total weight of a), b) and c) of a free-radical initiator, a) at least one monomer selected from the group consisting of &agr;,&bgr;-unsaturated monocarboxylic acids and their salts, &agr;,&bgr;-unsaturated dicarboxylic acids, their half-esters free of polyoxyalkylene side chains and their salts, b) at least on olefinic monomer selected from the group consisting of aromatic vinyl compounds, vinyl ethers, vinyl esters, nitrogen-containing vinyl compounds and aliphatic olefins, and c) from 0.

Abstract: A cement composition comprising a polymeric latex prepared by aqueous emulsion polymerization of a monomeric mixture comprising styrene and butadiene in the presence of a seed polymer prepared by aqueous emulsion polymerization of styrene and a salt of 2-acrylamido-2-methylpropanesulfonic acid.

Abstract: A material for improving the surface appearance of cementitious mouldings comprises a polyalkylene oxide compound which is selected from polypropylene oxide adducts of either polyethylene glycol or polyethylene oxide-ethylene diamine adduct, polypropylene oxide chains being attached to all terminal groups. The material may be added to a cementitious composition as an admixture or applied to the surface of a moulding which has not yet hardened.

Abstract: The present invention is an improved process for preparing a portland cement composition where the process comprises heat calcining a mixture comprising a source of calcium and a source of silicon to form clinker. The improvement comprises providing to the process a silicon containing product resulting from the hydrolysis of chlorosilicon by-product as at least a portion of the source of silicon.

Abstract: Disclosed is a process of manufacturing a lightweight particulate cementitious composition particularly adapted to the sorption of liquids comprising adding to a foamed cement slurry a particle forming agent, and aging the treated foamed slurry for a period of time sufficient for the particles to form and harden for subsequent handling. The bulk density, particle size distribution, and concentration of the agent are selected such that the cementitious composition has the desired density and such that at least 65% of the particles obtained after aging have the desired particle size.

Abstract: A method for milling Portland clinker for the production of gypsumless Portland cements is provided. The method comprises milling the Portland clinker in the presence of 0.01 to 0.05 weight % of a synthetic, organic, surface-active substance with wetting properties that is stable in an alkaline medium of pH 9-12, with the exception of the triethanolamide of dodecylbenzylsulphonic acid, to produce gypsumless Portland cements with specific surfaces of 350-750 m.sup.2 /kg.