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The article presents the results of laboratory trials for the smelting of high-carbon ferromanganese on highly-basic slags. Laboratory trials have confirmed that an increase in the basicity of ferromanganese production slags has a positive effect on the reduction of manganese to the metal and a decrease in the concentration of silicon in it. However, the high basicity makes the slag high-melting and tough, leading to large losses of manganese with the slag. The use of on borate fluxes solves this problem by affecting the physical and chemical properties of the final slags, which allows the process to be carried out at high basicities with the achievement of optimal technological indicators. The obtained positive results of laboratory experiments served as the basis for approbation the developed technology on a semi-industrial scale with the smelting of high-carbon ferromanganese by the flux method from the manganese ore of the «Bogach» Deposit. As a result of studying the smelting of carbonaceous ferromanganese in large-scale laboratory conditions, the possibility of converting manganese ores on highly-basic slags with appropriate regulation of the transport properties of slag to a standard metal with high technical and economic indicators was established. The best results are achieved when the CaO/SiO2 ratio in the slag is 1.8 and the boron oxide content in the slag is 0.8%. It is established that under these conditions, the obtained boron-containing highly-basic slags of carbonaceous ferromanganese are not subject to slaking.

Scientists of the Chemical-Metallurgical Institute named after Zh.  Abishev develop new types of highly effective alloys based on resource-saving technologies that allow the complex processing of natural and technogenic raw materials, such as carbonaceous waste, chrome ore fines, etc. Therefore, it has led to the creation of a onestage, slag-free and non-waste technology with the maximum use of all useful charge components. With disappearance of rich ore reserves, as well as the expansion of demand for raw materials and the development of technology, the rich ores are replaced by poorer and substandard ones that require new methods of processing. The maximum use of raw materials and industrial waste, if this is economically justified, is one of the basic requirements for the technology. This task is closely intertwined, and in many cases coincides with another task – the development of integrated methods of raw materials processing, which, in the general production cycle, allows using, if possible, all useful elements of raw materials. The main objective of the study is to find ways to improve the use of sub-standard chrome ore. As a reducing agent in the electrothermal smelting of the ACS alloy, instead of expensive coke, without which no process of carbothermic smelting is required, a cheap high-ash Borly coal was used. The coal ash, which mainly consists of silica and alumina, is an additional source of silicon and aluminum in the alloy. This technology will be simple and allows regarding substandard chromium ore as a complex metallurgical raw material, since not only chrome is used, but also the components of the waste rock – silicon and aluminum. As a result of the complete reduction of all charge oxides, this technology will make it possible to obtain a complex alloy of ACS with an approximate chemical composition: 39  –  43  % of chromium, 23  –  27  % of silicon, 7  –  10  % of aluminum. The transition of the main components of the charge to the alloy will be: 82  –  85  % of chromium, 68  –  70  % of silicon, 59  –  60  % of aluminum. In this paper, the results of experimental studies on the production of a complex alloy of ACS (aluminum-chromium-silicon) from high-ash coals of the Borly deposit and chrome ore minerals of the Donskoi GOK are presented. The course of furnace operation is described with a lack, excess, and also the calculated amount of the reducing agent. The ways of eliminating the upset in furnace operation are shown.

The article presents the results of calculating the thermodynamic parameters of compounds formed between the system components. They were used for a complete thermodynamic-diagram analysis of the Fe-Mo-Si-Al system, taking into account congruent compounds. As a result, it was found that this system consists of 8 elementary tetrahedral. The sum of the relative volumes of elementary tetrahedral is equal to one (1,000000), which confirms the correctness of the tetrahedron performed.