Effects of slag refining and vacuum treatment on de-phosphorus from MG-Si using CaO-SiO2-CaCl2 slag

Abstract

This paper presents a detailed analysis of the effect of slag refining and vacuum treatment on P removal from metallurgical-grade silicon using CaO-SiO2-CaCl2 slag. It demonstrates that both of CaO: SiO2 ratio and CaCl2 content have significant effects on the P removal. Increasing CaO: SiO2 ratio was found to decrease the P removal efficiency after slag refining and vacuum treatment, and the distribution of P shows a tendency to concentrate in the precipitated phase after slag refining. It is also determined that the highest removal efficiency of P was attained when CaCl2 content was 5wt%(CaO:SiO2=1:1), but no obvious change was observed on P distribution after slag refining of varying CaCl2 content. ? (2013) Trans Tech Publications, Switzerland.