An empirical formula for accurate calculation of liquidus temperature of blast furnace slags in SiO₂–Al₂O₃–CaO–MgO system

ABSTRACT

Precise numerical simulations of blast furnace (BF) rely on accurate and convenient thermophysical property models of BF slags. Liquidus temperature (T_liq) is one of the most fundamental properties of BF slag, however, the conventional phase equilibrium diagram method for T_liq calculation can be hardly used in numerical simulations. In this work, an accurate and simple empirical formulation suitable for T_liq calculation of BF slags in numerical simulations is established. The model was calibrated by 707 measurement representing 11 primary phase fields in SiO₂–Al₂O₃–CaO–MgO system. The calculated T_liq in present work agrees very well with the measured values, with an average error of only 17.1°C, which is much more accurate than CalPhad method. Present work also suggests that the liquidus region of BF slag at 1500°C should be slightly extended based on the classic phase equilibrium diagram.

KEYWORDS:

• Liquidus temperature
• blast furnace slag
• numerical simulation
• regressional model
• phase equilibrium diagram

Additional information

Funding

This study is partly funded by Natural Science Foundation of Jiangxi Province, China (20171ACB21042). The financial support is greatly acknowledged.