Representation of Oxidation Ability for Metallurgical Slags Based on the Ion and Molecule Coexistence Theory

Abstract

AbstractThe defined oxidation ability of metallurgical slags based on the ion and molecule coexistence theory (IMCT), i.e., the comprehensive mass action concentration of iron oxides, has been verified through comparing the calculated and the reported activity of iron oxides in the selected FetO‐containing slag systems. To calculate the defined comprehensive mass action concentration of iron oxides in the selected slag systems, a thermodynamic model for calculating the mass action concentrations of structural units or ion couples in CaO–SiO2–MgO–FeO–Fe2O3–MnO–Al2O3–P2O5 type slags, i.e., the IMCT‐Ni thermodynamic model, has been developed. The defined comprehensive mass action concentration of iron oxides is more accurate than the measured activity of iron oxides to represent the slag oxidation ability of the selected FetO‐containing slag systems. The calculated comprehensive mass action concentration of iron oxides or the reported activity of iron oxides in the selected FetO‐containing slag systems shows an increase tendency with an increase of optical basicity of the slags by taking as 0.93 and as 0.69, or as 1.0 and as 0.75, rather than by taking as 0.51 and as 0.48. The slag oxidation ability represented by the defined comprehensive mass action concentration of iron oxides or the measured activity of iron oxides is not only decided by the effects of iron oxides, but also by the comprehensive effects of both iron oxides and basic oxides as CaO or MgO or MnO in the selected FetO‐containing slag systems.