Factors Determining the Rate of the Process of Metal Bath Components Evaporation

The phenomenon of evaporation of volatile metal bath components can be observed in numerous process of both extractive metallurgy and refi ning. In some of them, this phenomenon can be considered positive, in others, however, to the contrary. In order to intensify the evaporation process or to restrain it, one must necessarily know the factors determining its rate. The most important of those factors include pressure inside the system, the gaseous atmosphere type, temperature and hydrodynamic properties of the system in which the given metallurgical process is being analysed. From a kinetic point of view, the process of volatile metal bath component evaporation can be divided into three main stages: transfer of the evaporating component from the body of the liquid phase to the interface, evaporation of the component from the interface, transfer of the evaporating component vapours from the interface to the core of the liquid phase. The mass fl ux of the evaporating component “i” transferred from the body of the liquid metal to the interface is characterised by the following relation: