Study on volatilization behaviour of BOF converter slag containing CaCl₂

ABSTRACT

The volatilization behaviour of CaCl₂-containing basic oxygen furnace (BOF) slags was investigated in laboratory at steelmaking temperature. During the melting process, the volatilization ratio was measured, and the volatile compounds were collected with some conductive tapes. Thermogravimetric analysis was conducted to clarify the volatilization of CaCl₂-containing slags, and the volatilization ratio was also calculated by the thermodynamic software HSC. It was found that volatilization takes place in both CaCl₂-containing and CaF₂-containing BOF slags, but their influential mechanisms are different. FeCl₂ is the main volatile compound in CaCl₂-containing BOF slags. The increasing contents of CaCl₂ and FeO in these slags are favourable for volatilization, while higher slag basicity plays the opposite role. In the case of CaF₂-containing BOF slags, the volatilization compounds have little relation to the FeO content in the slags, and the volatilization ratio is smaller than that of CaCl₂-containing BOF slag.

KEYWORDS:

• BOF steelmaking slag
• CaCl₂
• CaF₂
• FeCl₂
• FeO‌
• volatile compound
• volatilization behaviour
• melting process

Acknowledgments

Dr. Jiasheng Ru is acknowledged for his help in thermogravimetric analysis in the present study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant numbers U20A20272 and 52074073].