Study on dephosphorisation of hot metal pretreatment with Al 2 O 3 to replace CaF 2 in slag

Abstract

The substitution effect of Al₂O₃ for CaF₂ on hot metal dephosphorisation has been studied at 1723 K. The initial composition of the slag was 40%CaO (mass percentage)+52%Fe₂O₃+8%CaF₂. Then, Al₂O₃ was substituted for CaF₂ up to 8%. The hot metal initial silicon was 0·61%, and the P contents were 0·063, 0·073 and 0·091%. Experimental results showed that with increasing Al₂O₃ content, the melting point of the slag slightly increased, and the oxidising power and phosphate capacity for the slag were enhanced, which led to an increase in dephosphorisation. The range of phosphorus content at the end point was between 0·009 and 0·014%, and the corresponding dephosphorisation varied from 82·5 to 89·0%. This result may be acceptable for industrial use.

Get full access to this article

View all access options for this article.

References

Peng

Wang

Liu

and Dong

: ‘A study on dephosphorization of hot metal pretreatment by low fluoride slag’, Special Steel, 2009, 30, (1), 54–57.

Wang

Dong

Zhou

and Peng

: ‘Study on low fluoride dephosphorization slag of hot metal’, J. Chin. Rare Earth Soc., 2010, 28, 500–504.

Mizukami

Ishikawa

and Hirata

: ‘Dissolution mechanism of fluorine in aqueous solution from fluorine containing synthetic slag’, ISIJ Int., 2004, 44, (3), 623–629.

Wang

Zhang

Guo

Chen

and Dong

: ‘Effect of oxygen potential on De–Si and De–P during hot metal pretreatment’, J. Iron. Steel Res., 2000, 12, (6), 11–15.

Huang

: ‘Principles of steel metallurgy’; 2002, Beijing, Metallurgical Industry Press.

Tian

Kong

Cai

Wang

Shi

and Zhu

: ‘Deep dephosphorization ability of BaO–CaO–CaF₂ flux for liquid steel’, J. Univ. Sci. Technol. Beijing, 2005, 27, (3), 294–297.