A Review of Slag Splashing

Abstract

This review critically evaluates the factors affecting the process of slag splashing. Two mechanisms are involved in slag splashing, namely ‘slag wash coating’ and ‘slag ejection coating’. Our knowledge of slag splashing is largely based on physical modelling studies. It is necessary to optimise the following for good slag splashing:
(ii) The characteristics of the nitrogen blow (Gas flow, Lance height, Lance angle, Slag depth); and
(iii) Slag composition.
It is important that the slag contains the right blend of low-melting and high-melting phases. The low-melting (FeO-rich) phases ensure good adhesion between the slag and refractory whereas the high-melting phases provide erosion resistance and a thermal barrier. Good slag properties are obtained with a FeO content of ca. 13% and MgO should be supersaturated (>8% MgO) to ensure that the slag is MgO-saturated rather than CaO-saturated so that high-melting MgO · Fe₂O₃ is formed rather than the low-melting calcium ferrites.
The factors affecting the uniformity of the slag-splashed layer are discussed.