Improvement of Technical and Economic Performance of Blast-Furnace Smelting by Pellet Composition Optimization

One of the main methods to intensify blast-furnace smelting is to improve the quality of the sintered raw materials. The article presents the study results of the influence of the composition and metallurgical properties of various Mikhailovsky GOK pellets introduced into the blast-furnace charge based on the technical and economic indicators of the blast-furnace treatment. The studies include physical modeling of pellet production of various composition, experimental determination of their metallurgical properties, as well as blast-furnace smelting simulation using the balance logical-and-statistical model of the Institute of Metallurgy, Ural Branch of the Russian Academy of Sciences (IMet). According to the simulation results, the productivity of the blast-furnace process increases when using all the test pellets, and the specific coke consumption decreases. It is revealed that when using iron-rich pellets in the charge, the sulfur concentration in the slag is significantly higher, which creates the risk of producing substandard cast iron. Based on the obtained data analysis, the technology for the use of enriched pellets (SiO₂ at the level of 6%) seems to be optimal, as it provides an increase in productivity with a relatively low coke consumption and acceptable slag sulfur content.