Emulsification of Metal in Molten Salt by Gas Bubblin

In the steelmaking process, metal droplets are generally emulsified into slag, a process called “metal emulsion.” It is well known that the impurity content in metal droplets dispersed in a slag phase is lower than that in the bath phase. This fact indicates that the impurities can be removed more efficiently in the dispersed phase than in the bath phase because the dispersed droplets have a larger interfacial area for reaction. Thus, metal emulsion has a significant potential for improving reaction efficiency. In this study, the formation of a metal emulsion was experimentally evaluated by using Pb, Al, and Sn as the metal phases and chloride salt as the slag phase, and the influence of gas flow rate on the formation of metal droplets was clarified. The results revealed that the volume of the droplet increased with increasing gas flow rate in the Sn–salt system. However, the volume of the droplet in the Al– and Pb–salt systemsincreased with increasing gas flow rate,reached a local maximum value, and then decreased. Finally, the dimensionless analysesof droplets dispersed in this study were carried out in order to make comparisons with other systems reported previously