Experimental research of the regularities of iron-bearing ore desulfurization for the temperature conditions of liquid phase sintering

The results of experimental analysis of the regularities of chemical and metallurgical process of iron-bearing ore desulfurization for different conditions of liquid phase sintering are presented. This process is conducted with addition of catalytic impurities and variation of chemical composition of the heat-carrying gas, in order to reveal the optimal procedure of chemical and metallurgical process of ore smelting, which provide maximal possible removal of impurities from ore composition. It was found out for iron-bearing ore raw material that the rate and temperature conditions of impurities sintering depend on chemical composition of additives and physical state of initial material. The data about the chemical and metallurgical process of iron-bearing ore desulfurization, depending on ore coarseness and addition of solid fuel at low temperature during smelting process, are obtained. It was also established that lowering of the starting temperature for impurities decomposition and acceleration of desulfurization in the area of charge heating can be achieved via charge fluxing by fluorine-containing limestone and decrease of oxygen content in a gaseous phase. Essential deviations from solid phase procedures in the mechanism of sulphate decomposition at the temperatures of liquid phase sintering are revealed. Analysis of the experimental data allowed to establish necessity of introduction of the dual-stage route in the technological process of ironbearing ore desulfurization; this route includes solid phase and liquid phase removal of sulfuric impurities, while liquid phase removal should be implemented with high oxidation degree of the slag phase. The study was supported by the Russian Science Foundation, grant No. 22-11-00335 (https://rscf.ru/en/project/22-11-00035/).