Resumo:
The research in steel dephosphorization were driven by the increasing demand for high-quality steel with fewer impurities. One of these impurities is the phosphorus. It is an undesirable element in steel, because of its deleterious effect in steel properties. In the last decades, researchers have studied dephosphorization to deduce expressions based in chemical composition and temperature. These expressions, deduced using equilibrium data, did not achieved a good correlation with industrial data. All expression can be written as a sum of a basicity term, an oxygen potential term, a temperature term and a constant of adjustment. This paper aims to create a new expression using, industrial data (slag and steel) and the results obtained by the thermodynamic program FactSage v. 7.2 to achieve a better correlation. The results given by FactSage were the Lp and viscosity of the slag, they were considered as an equilibrium term and kinetic term, resulting in another expression. Besides that, the expression will be tested using another group of industrial data. As a result, the new model had a good correlation with the industrial data R2=0.89, and with the second industrial data, R2 = 0.83. This fact evidences the importance of scrap load in dephosphorization.