Introduction. Solving the urgent problem of the production of special concretes using certain varieties of substandard natural raw materials and a number of industrial wastes will support introducing the principles of resource saving and improving the technological features of production.Aim. To make a comprehensive assessment of the impact of sulfuric acid production wastes and substandard natural clay raw materials on the production of high-quality and durable concretes for special purposes.Materials and methods. Easily fusible clay rocks serve as a raw material for the production of expanded clay gravel. Organic (solar oil) and ferruginous (pyrite cinders) additives were used. X-ray analysis was carried out to determine the crystalline phases in the clay of the Nikolskoe oil-field, in the resulting expanded clay gravel, as well as to analyze the factory bulk samples of pyrite cinders. A tubular electric furnace was used for firing in a two-stage mode of 700 and 1100 °C to obtain high-strength expanded clay gravel under laboratory conditions. The research involved studying parameters of phosphate binder formation and properties of iron phosphate concrete based on H3PO4 and sulfuric acid industry wastes – pyrite cinders.Results. It was found that Nikolskoye field clay forms a good raw material for the production of high-strength heavy expanded clay gravel with a strength of up to 550 kg/cm2, water absorption of 1.5 % and resistance to aggressive environments, thereby making it suitable for manufacturing special concretes. The results obtained specify the test methods and technical requirements, control methods and product acceptance rules, thus improving the quality and durability of the concretes considered.Conclusions. The investigated non-bloating clay can be used with organic and ferruginous additives to obtain high-strength expanded clay gravel for the manufacture of structural concretes. A mixed iron phosphate binder serves for producing heat-resistant concretes for linings of melting and casting units in non-ferrous metallurgy with high resistance and durability.
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