When constructing deep wells for oil and gas production in difficult geological conditions, special lightweight oil-well cements are used. To reduce the density and water separation of the cement slurry as well as to increase the strength, corrosion resistance of cement stone and the quality of well cementing, opal-containing rocks, fly ash, microsphere and other lightening additives are introduced into the cement composition. The influence of sedimentary rocks, such as opoka, tripoli, and diatomite containing from 43 to 81% amorphous silica on the grindability, rheological and physical-mechanical properties of lightweight oil-well Portland cement has been studied. The twelve cement compositions with different content of additives (from 30 to 45%) that meet the requirements of the standard for density, spreadability, water separation, thickening time and flexural strength were selected. The introduction of 45% diatomite or tripoli significantly reduces the duration of cement grinding, provides the cement slurry with water-cement ratio of 0.9 with better density and flexural strength, respectively, 1480 kg/m3 and 1.1–1.5 MPa.

Ferrochrome slag is waste resulted from the manufacture process of ligature melting. It is a porous material of dark grey-green colour with 2530 kg/m3 density and the open pores size from 1mm to 5 mm. After crushing crushed slag possesses the following characteristics or properties, namely: the least grain coarseness is 20 mm, the largest one is 120mm, the needle and plane grain content is 25.5%, so it refers to ordinary group of crushed stone, its crushability grade is M800, attrition grade AI and frostproofness is F25. Screenings or riddlings obtained by crushing and fractioning of slag possess gradation factor 2.9 and it refers it coarse sand group of class II. Concrete mixes have been investigated by using granite aggregates and ferrochrome ones. It is determined that mixes containing ferrochrome aggregate are stiffer than the traditional ones. In this case strength characteristics of the experimental concretes are 1.7 times higher than those of the traditional concretes. When evaluating approximate cement consumption for concrete made of ferrochrome slag aggregates it was established that such concrete possesses strength of B30 class, but by using granite aggregate in the concrete mix result in strength of B20 class.

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When producing iron ore concentrate at Kachkanarsk integrated mining works 2 types of wastes are formed, namely: final tailings of dry magnetic separation (DMS) and final tailings of wet magnetic separation (WMS). Final tailings of wet magnetic separation (WMS) are pulled off or dumped into disposal area up to 45mln tons annually causing great damages to the environment. These final tailings are finely dispersed materials, their chemical composition is oxides of silicon, aluminium, calcium and iron in general. All this allows to use the wastes under consideration to produce Portland cement clinker replacing clayey and iron components in the raw material mixture completely and limestone partially. The replacement of clay with final tailings of ore enrichment are suitable to manufacture clinker raw material mixture allowing to use two-component raw mix instead of three-component and four-component one thus simplifying the technology of cement production and improving the ecological situation in Sverdlovsk region. The utilization of final tailings for concentration of titano-magnetite ores decreases fuel consumption when burning clinker compared to the traditional compositions. Experimental cement meets all the requirements of the Russian Standard 10178 as to their chemical and physic-mechanical properties and have grade 500.