The relationship between theoretical substitution ratio of CaO and BOF process parameters based on thermal equilibrium

In consideration of material balance, relationship between the surplus heat and the parameters including compositions and temperature of molten iron, amount of scrap steel and tapping temperature were established by heat balance calculation in converter. Meanwhile theoretical substitution ratio of CaO η with limestone instead of active lime in steelmaking was defined, and the function relation between theoretical substitution ratio of CaO and surplus heat was established for exploring the effects of parameters on theoretical substitution ratio of CaO. The results indicated: theoretical substitution ratio of CaO can be significantly improved by increasing temperature and carbon content of molten iron. When temperature of hot metal 1300°C, theoretical substitution ratio of CaO decreased with the increasing of silicon content. When the basicity of slag and the tapping temperature were constant, theoretical substitution ratio of CaO can be significantly increased by reducing the amount of scrap steel.