Phase Relation of CaO–Al₂O₃–Fe_tO–P₂O₅ Slag and Phosphorus Distribution between This Slag and Liquid Iron

Abstract

Amount of steelmaking slag emission is increasing due to strong demand for high quality steel. Development of slag and process that can remove impurity at high efficiency is required to decrease slag discharge volume. Phosphorus is a typical impurity in steel and it can be removed by slag with high CaO and Fe_tO activity. CaO–Fe_tO–P₂O₅ system has two liquid phase region that has CaO and Fe_tO high activity. It was confirmed that CaO–MgO–Fe_tO–P₂O₅ two liquid phase slag can remove phosphorus at high efficient in the previous work. The phase relation and ability of phosphorus removal by CaO–Al₂O₃–Fe_tO–P₂O₅ system was investigated in the present work.