Characterisation of the Effect of Al₂O₃ on the Liquidus Temperatures of Copper Cleaning Furnace Slags Using Experimental and Modelling Approach

Abstract

Most metallurgical smelting processes operate over a limited range of compositions and temperatures but generally, even with complex slag systems, within a given primary phase field. Knowledge of the sensitivity of the liquidus to changes in composition enables improved temperature control and stability of operation. The paper describes a general approach that was used to characterize the liquidus temperatures of the “Cu₂O”–“FeO”–SiO₂–Al₂O₃ slags in an electric slag cleaning furnace operation as function of the principal chemical components using a combination of available computer based thermodynamic database descriptions of complex slags and targeted series of laboratory experiments. An approximate mathematical relationship, valid for a limited range of compositions and temperatures, has been developed describing the liquidus temperature of the slags as a function Fe/SiO₂ ratio, Cu, and Al₂O₃ concentrations in slag.

Fig. 9 Effect of Al₂O₃ in bulk on the mass%solid as function of Cu in bulk at fixed temperature = 1200°C and Fe/SiO₂ ratio in the bulk = 1.5 mass/mass as predicted by the polynomial equation obtained in the present study.