A Thermochemical Strategy for Dephosphorization of Liquid Iron and Minimization of Slag Volume

摘要

Dephosphorization of liquid iron can be expressed by the following reaction: 2(P)+5 (Fe_2O_5)+5Fe with is favored by high FeO and low P_2O_5 activities. As this reaction proceeds, the activity of FeO inevitably decrases while that for P_2O_5, increases. In order to counter these activity changes additions are made of FeO and CaO, which, in turn, result in an increase in slag volume. In this study a zirconia cell technique was employed to determine the FeO activities within 3- and 4-phase assemblages in the CaO+P_2O_5+FeO and CaO+P_2O_5+SiO_2+FeO systems, respectively. Within these regimes, the activities of FeO and P_2O_5 remain constant, which enhances the dephosphorization reaction and at the same time permits a reduction in slag volume.