A model for estimating the viscosity of blast furnace slags with optical basicity

Abstract

Viscosity is an important physical property of blast furnace slags and has a great influence on blast furnace operations. Because of time consumption and difficulties encountered during high temperature experimental measurement, viscosity data are also limited, so a reasonable and accurate estimation model is required to provide the data for controlling and optimizing the blast furnace process. In the present study a viscosity model was proposed for blast furnace slags. In the model the activation energy was calculated by the optical basicity corrected for cations required for the charge compensation of AlO₄ ⁵⁻, and the temperature dependence was described by the Weymann-Frenkel equation. The estimated viscosity values of the CaO-Al₂O₃-SiO₂, CaO-Al₂O₃-SiO₂-MgO, and CaO-Al₂O₃-SiO₂-MgO-TiO₂ systems fit well with experiment data, with the mean deviation less than 25%.

Keywords

blast furnace / slags / viscosity / optical basicity / charge compensation / activation energy

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