Fundamental Aspects of Dissolution of Lime into Steelmaking Slags

Abstract

A fundamental analysis is presented to describe the dissolution behavior of lime (CaO) in FeO-containing slags. FeO present in steelmaking slag is seen to penetrate preferentially into the lime particle and form a (CaO�FeO) layer around it, thereby a pathway for outward diffusion of CaO into the slag and subsequent formation of dicalcium silicate. In the present work, the lime dissolution behavior is described in terms of the chemical potential gradient of CaO between the lime particle and slag. The chemical potential gradient is more fundamental for calculating fluxes in concentrated melts in which the activities are far from ideal, which has been ignored by previous researchers. The model developed in the present work is used to compare the mass transfer coefficients for a variety of experimental conditions. In addition, other factors affecting the dissolution are lime particle morphology, activity of silica in slag, slag viscosity, temperature and turbulence in slag. � The Indian Institute of Metals - IIM 2024.