The invention relates to the use of a hydraulic binder containing calcium aluminate, obtainable by a method in which a) prepared amorphous residual material rich in aluminium oxide and/or aluminium hydroxide is heated after the addition of a b) calcium ion-containing binder component and c) water, for the production of a constructing material.

A method for processing water treatment residuals, or other amorphous aluminium oxide or aluminium hydroxide rich waste residuals, for use in the manufacture of hydraulic binders, comprising heating the residuals to remove water and oxidise organic material contained therein, comprising controlling the temperature of the residuals during heating such that they are heated to a temperature no higher than 800° C., more preferably no higher than 650° C., to ensure that aluminium compounds in the WTR, in particular aluminium oxide and aluminium hydroxide, remain in an amorphous state. The method may comprise controlling the temperature of the water treatment residuals such that they are heated to a temperature between 350° C. and 650° C., more preferably between 400° C. and 500° C.

Processes and plants for producing cement clinker, wherein no recirculation of preheater exhaust gases occurs and the ratio of solid fed in to exhaust gas in the preheater is set to greater than 1.0 kg of solid to gas.

A cement manufacturing plant can include at least one emission abatement mechanism. In some embodiments, the emission abatement mechanism can utilize a plurality of pulsed gases passed through a reactor to treat a solid particulate material passed through the reactor. The pulsed reactant gas can be pulsed through the reactor so that the pulsed gas passes from a middle portion of the reactor to a first end of the reactor at which the solid particulates can be fed into the reactor. In some embodiments, the reactant gas can be output from the first end to a down corner or other reactant gas conduit for transport to a treatment device.

A method and system for producing low-alkalinity sulphoaluminate cement with a new mineral system using steel slag. The method includes the following steps: evenly mixing and homogenizing ground steel slag with dry desulfurization gypsum, aluminum ash and carbide slag according to a set ratio; and conveying the homogenized raw meal to a rotary kiln for calcination to obtain cement clinker, where the calcination temperature is 1200° C.-1270° C., and the calcination time is 20-60 min; the alkalinity modulus of the homogenized cement raw meal is 0.81-0.9, and the Fe.sub.2O.sub.3 content is 8-13%. The method breaks through the requirements on contents of calcium, aluminum and iron in traditional sulphoaluminate cement production, and realizes application of a large amount of steel slag.

Method and installation for calcining cement raw meal in a calciner whereby fuel and a calciner oxidant having an oxygen content of at least 30% vol are introduced into the calciner so as to generate either an oxidant-lean zone or a fuel-lean zone in the calciner located between the lowermost fuel inlet level and the lowermost oxidant inlet level of the calciner, between 50% and 100% by weight of the raw meal being supplied to the calciner upstream of and/or within the oxidant-lean, respectively the fuel-lean zone.

Method and installation for calcining cement raw meal in a calciner whereby fuel and a calciner oxidant having an oxygen content of at least 30% vol are introduced into the calciner so as to generate either an oxidant-lean zone or a fuel-lean zone in the calciner located between the lowermost fuel inlet level and the lowermost oxidant inlet level of the calciner, between 50% and 100% by weight of the raw meal being supplied to the calciner upstream of and/or within the oxidant-lean, respectively the fuel-lean zone.

A method of producing clinker includes placing a pre-clinker mixture comprising a source of CaO into a starting material feed port in a vertically-oriented reaction chamber of a vertical reactor. The method includes placing a gaseous combustion mixture into the combustion mixture inlet. The method includes combusting the gaseous combustion mixture within the vertical reactor to heat the pre-clinker mixture, release CO 2 therefrom, and form the clinker therefrom. The method also includes removing the clinker from the product exit port.

A method of manufacture of Portland cement clinker is described in a dry process that captures the carbon dioxide emitted from the calcination of carbonate minerals, principally limestone. The process uses an indirectly heated, counter-flow reactor to pre-heat and calcine the cement meal to produce a separate calcined meal and carbon dioxide gas stream, with external heat being provided by the combustion of a secondary fuel stream with pre-heated air. This calcined meal is injected into the conventional rotary kiln, where the hot flue gas from combustion of the primary fuel with pre-heated air is used to fuse, react and sinter the powders to form granules of cement clinker. The clinker and carbon dioxide streams are cooled by the air pre-heaters.

A method of calcining a clay material for use as a supplementary cementitious material, includes providing a raw clay material, optionally drying the raw clay material, granulating the raw clay material in order to obtain raw clay granules, calcining the raw clay granules to obtain calcined clay granules, and grinding the calcined clay granules to obtain a pulverulent supplementary cementitious material.