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The preparation of sulfoaluminate clinkers from low-aluminate natural and technogenic raw materials that are substandard for the production of aluminate cement due to the high content of silicon oxide is considered. Raw mixtures for the synthesis of sulfoaluminate clinkers of the most approximate chemical composition from natural raw materials and from technogenic products are calculated. The technological properties, phase compositions of clinkers obtained by sintering, and hydraulic properties of sulfoaluminate clinkers and compositions with their application are compared. The presence of a sulfate component avoids the formation of clinkers in the hydraulically inert gehlenite. The presence of alkaline and other impurity compounds in the used technogenic waste reduces the synthesis temperature of sulfoaluminate clinkers by 130 degrees; changes the phase composition and properties of cement; shifts the effect of sulfation from the aluminate phase to the silicate phase. In clinkers, mainly calcium sulfoaluminate is formed from natural raw materials, and calcium sulfosilicate is formed from technogenic products. It is established that cement stone made of clinker based on natural raw materials has high strength, including in the early stages of hardening. From the considered technogenic waste, it is possible to obtain a sulfoaluminate additive of low-temperature roasting, which increases the strength characteristics of the stone from the binding composition in the early stages of hardening.

Problems of energy saving in the firing of raw sludge is an important factor in the long-term development of cement production. An integrated approach to the study of the properties of raw materials and additives makes it possible to find ways to save fuel and energy resources. Reducing the moisture content in the sludge by the use of plasticizing reagents is one way to solve the problem of reducing energy consumption during firing of sludge. Reducing the moisture content of raw sludge from 41% to 35.5% makes it possible to reduce energy consumption by 23.3 kilograms of equivalent fuel per ton of clinker. The most effective type and concentration of plasticizing reagent was selected. A decrease in the moisture content and an increase in flowability were studied on a model raw sludge based on kaolinite-montmorillonite clay, chalk and pyrite cinder – a coal -alkaline reagent (0.1 wt.%). The studied reagents were arranged in the following sequence according to the effectiveness of increasing the flowability of sludge: coal-alkaline reagent, Polyplast SP-1, calcium lignosulfonate (LST), Viscocrete20HE, Linamix PK.

A principally novel technology for molding and compacting articles from low-moisture powder materials by continuous zonal injection directly into open molds is suggested. The method excludes air inclusions, the elastic aftereffect, the inaccuracy of the sizes of the articles, and other defects typical for cyclic semidry pressing. The use of the new technology in the production of refractories makes it possible to increase their density, decrease the forces acting on the material by 1 – 2 orders of magnitude (i.e., to the ultimate strength of the greenware), increase the accuracy of the sizes, decrease the expenses per unit product, and increase the output of the molding equipment.