Siberian Federal University, Krasnoyarsk, Russia.

N. V. Vasyunina, Cand. Eng., Associate Prof., Dept. of Metallurgy of Non-ferrous Metals, e-mail: nvvasyunina@yandex.ru
B. P. Kulikov, Dr. Chem., Leading Researcher, e-mail: kulikov-boris@yandex.ru
I. V. Dubova, Cand. Eng., Associate Prof., Dept. of Fundamental Natural Science Education, e-mail: idubova@mail.ru
A. S. Samoylo, Research Engineer, e-mail: x_lab@rambler.ru

The article is devoted to the substantiation of the technology for producing artificial fluorite for the needs of ferrous metallurgy from fluorocarbon-containing waste from aluminum production. An analysis of the use of natural and artificial fluorite in flux products in the production of cast iron and steel was carried out. It has been shown that the existing deficit of fluorspar can be compensated by using fluorocarbon-containing waste from aluminum production. The rationale for the choice of technology for causticization of finely dispersed fluorocarbon-containing waste in order to obtain a product containing synthetic fluorite and graphitized carbon is given. Based on an analysis of the phase and elemental compositions, a fluorine-containing raw material source for causticization was selected - coal foam. The mechanism is described and thermodynamic modeling of the processes occurring in the system during the causticization of coal foam is given. The causticization technique is described. The phase and elemental compositions of the initial raw materials and the dried product were determined using XRF and X-ray diffraction methods. The composition of the liquid phase was determined using chemical titrimetric methods. As a result of laboratory experiments on the causticization of coal foam, the kinetic limitations of the causticization process were assessed, on the basis of which the optimal operating parameters of the process were established. The possibility of obtaining a flux additive for steel smelting by caustification of fluorocarbon-containing waste has been shown. A caustification product was obtained containing CaF₂ = 60-65 %, as well as alumina and graphitized carbon, which in composition appears to be a fairly promising flux additive for the production of cast iron and steel. Graphitized carbon in the flux additive will play the role of a burnable additive, reducing energy costs for the process. A caustic alkali solution with a NaOH concentration of 15-20 g/l obtained using non-waste technology can be used as a gas cleaning solution at the stage of “wet” cleaning of waste gases.
The research was carried out using the equipment of the Center for Collective Use “Knowledge-intensive methods of research and analysis of new materials, nanomaterials and mineral raw materials” of the Federal State Autonomous Educational Institution of Higher Education “Siberian Federal University”.
The work was carried out within the framework of the state assignment for scientific research of the Federal State Autonomous Educational Institution of Higher Education "Siberian Federal University", project number FSRZ-2023-0009.

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