(S098)Effect of Na2O on the Distribution of P2O5 between Solid Solution and Liquid Phase in Slag with High P2O5 Content

摘要

The phosphorus (P) content in hot metal will increase in future, because iron ores are steadily deteriorating in quality. To meet the demand for low P steel and to ease the environmental burden, a highly efficient dephosphorization process with less slag is necessary. Hot metal dephosphorization with a multi-phase slag which contains solid solution (2CaO·SiO2-3CaO·P2O5) is well developed in Japan. Na2O addition to slag is considered an effective method for increasing the efficiency of dephosphorization [1]. In addition, Na2O modification also facilitates P recovery from dephosphorization slag with high P2O5 content via selective leaching [2]. Therefore, it is necessary to investigate the effect of Na2O on the distribution ratio of P2O5 between solid solution and liquid phase in the CaO-SiO2-Fe2O3-P2O5-Na2O slag system with a high P2O5 content.