DETERMINATION OF THE RATIONAL COMPOSITION OF REAGENTS FOR THE COMPLEX REFINING OF LIQUID CAST IRON AT THE OUT-OF-FURNACE TREATMENT STAGE

Abstract

The paper is devoted to the issue of complex treatment of cast iron. Possible chemical transformations that can occur when reagents are introduced into liquid cast iron are analyzed, and expressions for calculating the equilibrium constant Kr, depending on temperature, are obtained. Graphical dependences of the equilibrium constants on temperature for these reactions were also constructed. The calculations were performed for desulfurization reactions, carbonate dissociation reactions, oxidation of cast iron impurities due to interaction with carbon dioxide, and for the interaction of liquid cast iron components with iron oxides. Thermodynamic calculations have established that the mixture for the complex refining of liquid cast iron at the out-of-furnace treatment stage should belong to the chemical system CaO - Na2CO3 - FeO(Fe2O3) - Al. The specific ratio of components is determined by the required refining result.