Вибір базових компонентів шлакоутворюючої суміші для одностадійного видалення домішок із чавуну

Abstract

The article is devoted to research on the development of a variant of the component composition of the slag-forming mixture during complex processing of cast iron for the detection of such impurities as silicon, sulfur and phosphorus. The purpose of the work is to study the composition of soda-containing slag on its physical and chemical properties and to identify the optimal ratio of refining slag components. Using the structure of the model of the process of processing cast iron by injecting reagents into the melt volume through the immersion nozzle, the thermodynamic probability of reactions occurring in the primary zone (at the outlet of the reagents from the nozzle of the nozzle) and the secondary reaction zone formed when the reaction products flowing in primary reaction zone. The value of the equilibrium constants of the corresponding reactions was calculated to assess the priority of the course of reactions of the interaction of system components in the primary reaction zone. The conducted thermodynamic analysis of the simultaneous removal of sulfur and silicon from cast iron by blowing powdered lime in a stream of oxygen and introducing additional reduction into the melt made it possible to state that during the oxidation of silicon with gaseous oxygen for desulfurization of cast iron with the resulting slag, it is advisable to additionally introduce a reducing agent into the melt. The technological parameters and main results of the experimental study of the process of out-of-furnace desiliconization and desulfurization of cast iron by blowing slag-forming materials into 350 kg buckets at the experimental plant are presented. Based on the results, data were obtained on the influence of the basicity of soda-containing slag on its viscosity and temperature. Using the theory of directional chemical bonding, the influence of the basicity of soda-containing slag on its physical and chemical properties was studied, and the optimal ratios of refining slag components were found.