An Approach to Modeling Al2O3 Containing Slags with the Cell Model

Abstract

The cell model originally developed by Kapoor and Frohberg for binary and ternary silicate melts was later extended to multi-component liquid slags by Gaye and Welfringer. CSIRO has extended the application of this model to describe the behaviour of a large number of oxide species commonly found in metallurgical slags. One limitation of the model was that when using only binary parameters to model ternary or higher order systems, the thermodynamic behaviour of the components in Al2O3 containing systems cannot be represented accurately. Based on an analysis of the structural role played by oxide components in the CaO-Al2O3-SiO2 system, two ternary parameters have been introduced to account for the influence of Al2O3 on Ca-Si interaction and CaO on Al-Si interaction, respectively. The introduction of the ternary parameters resulted in significant improvements in the model description of Al2O3 containing ternary and higher order systems. As a structurally based model, the cell model calculates parameters related to the degree of polymerization in silicate melts. These parameters have been used in a structurally based viscosity model for calculating the viscosity of silicate melts. The fit to a recent set of data has demonstrated the capability of the viscosity model to account closely for the cation effects.