Thermodynamic Properties and Viscosities of High-Titanium Slags

Abstract

The influence of TiO₂, binary basicity and Al₂O₃/TiO₂ ratio on the heat capacity, enthalpy and slag fluidity of CaO–SiO₂–MgO–Al₂O₃–TiO₂-based slag at 1693 K, 1723 K, and 1753 K (1420°C, 1450°C, and 1480°C) was investigated in this work. From the calculation results, it was found that the heat capacity of the slag increased with the increasing of TiO₂ content and the Al₂O₃/TiO₂ ratio and with the decreasing of basicity in the experimental temperature range. Enthalpy change increased with the increasing Al₂O₃/TiO₂ ratio and the decreasing of TiO₂ content. With the increasing of basicity, the slag temperature rises slightly and the viscosity decreases along with it. Additionally, the larger the basicity, the smaller the viscosity fluctuation under heat decrement. Therefore, a proper increase in basicity contributes to reduce viscosity fluctuation, for the current slag system, the appropriate basicity should be 1.15–1.20. Besides, the fluctuation of the temperature reaches a small value around the Al₂O₃/TiO₂ ratio is 0.6, and in metallurgical production, the heat input should be adjusted in time according to titanium content charge fluctuations, thus ensuring good fluidity and an adequate reaction between the slag and metal. The above experimental results can provide a reference for ironmaking enterprises using more vanadium–titanium magnetite ore.