Numerical model of inclusion separation from liquid metal with consideration of dissolution in slag

Abstract

The transport of inclusion particles through the liquid metal/molten slag interface and their dissolution in the slag are two key processes of inclusion removal. Based on the latest version of inclusion transport model that takes into account full Reynolds number range and a dissolution kinetics model, a coupled model was developed to simulate the whole process of inclusion removal, from floating in the liquid steel to crossing the interface and further to entering and dissolving in the molten slag. The interaction between the inclusion motion and dissolution was discussed. Even though the inclusion velocity is a key parameter for dissolution, the simulation results show no obvious dissolution during moving state because the process is too short and most of the inclusions dissolve during its static stay in the slag side above the interface. The rate-controlling step of inclusion removal is the transport through the steel–slag interface for the small-size inclusion and static dissolution above the interface for the large-size inclusion, respectively.