Thermodynamic simulations and isothermal solubility diagrams as tools for slag foaming control

In this communication, the advantages and difficulties of the slag foaming process control are presented, highlighting the thermodynamic simulations role in the design of isothermal solubility diagrams (which express the relationship between MgO and FeO contents, in weight percentage, for a specific basicity and temperature). These diagrams can predict the liquid composition changes required in order to induce a longer foam lifetime at the upper surface of molten slags. Mathematical models and experimental tests have been used to understand the slag foaming phenomenon, however they do not simultaneously consider all variables involved in this process. Thus, a comparison between some experimental results and isothermal solubility diagrams was made in this work. According to this evaluation, the use of thermodynamic simulations can be a good alternative to help keeping the slag foam generation while some equipment is being used in the steel production. The use of isothermal solubility diagrams provides a clear image of which adjustments can be made in order to attain stable foam, reducing the needs for some additional experimental analyses.