Evaluation of Viscosity of Molten SiO₂-CaO-MgO-Al₂O₃ Slags in Blast Furnace Operation

Abstract

The viscosity of molten SiO₂-CaO-MgO-Al₂O₃ slag was measured using a rotating cylinder method at high CaO and Al₂O₃ concentration regions to search for a slag with low melting temperature and low viscosity. The experimental results showed that the viscosity of molten 35mass%Al₂O₃-43.1mass%CaO-7.5mass%MgO-14.4mass%SiO₂ slag at 1673 K was lower than 0.6 Pa·s that satisfies the fluidity in blast furnace operation.
The experimental results were compared with the calculated results of the viscosity model derived by the authors. The viscosity of molten SiO₂-CaO-MgO-Al₂O₃ system can be evaluated from our model in wide Al₂O₃ concentration range.