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.

• Periodical: Advanced Materials Research (Volume 815)
• Pages: 773-777
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.815.773
• Online since: October 2013
• Authors: Liu Qing Huang, Hui Xian Lai, Ming Fang, Cheng Hao Lu, Juan Chen, Yan Xu Lin, De Qin Yu, Jin Tang Li, Wen Hui Ma, Jian Ning Shen, Xue Tao Luo
• Keywords: De-Phosphorus, Metallurgical-Grade Silicon, Slag Refining, Vacuum Treatment

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