Assessment of the Adequacy of the Model for Determining the Composition and Properties of Final Slag in a Blast Furnace

The correctness of the calculated composition and characteristics of the final slag at a blast-furnace engineer’s workstation is assessed. The developed model accounts for the combined effect of the components of the slag on its properties by calculating the viscosity polytherms in the range of temperatures in the blast furnace. The use of the model is extended to slags with widely varying composition and content such as Al₂O₃ 3–17%; MgO 5–20%; SiO₂ ≥33%; СаО ≥ 33%, TiO₂ <2.0% with slag basicity CaO/SiO₂ = 0.8–1.2. The results of statistical processing of more than 111 thousand iron tappings and about 300 periods of the slag conditions for eight MMK blast furnaces are presented. The coefficients of pair correlation between the actual performance of the blast furnace during individual tappings and the performance predicted by the process model were calculated. The pair correlation coefficient between the actual and calculated (from the chemical composition of the charge materials) contents of individual components in the final slag was from 0.85 to 0.97. Comparison of the viscosity of slags of different compositions and at different temperatures showed that the experimental data and the calculated values are in agreement with a relative error of no higher than 5.4%.