Study on volatilization behaviour of BOF converter slag containing CaCl₂

Abstract

The volatilization behaviour of CaCl 2 -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 CaCl 2 -containing slags, and the volatilization ratio was also calculated by the thermodynamic software HSC. It was found that volatilization takes place in both CaCl 2 -containing and CaF 2 -containing BOF slags, but their influential mechanisms are different. FeCl 2 is the main volatile compound in CaCl 2 -containing BOF slags. The increasing contents of CaCl 2 and FeO in these slags are favourable for volatilization, while higher slag basicity plays the opposite role. In the case of CaF 2 -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 CaCl 2 -containing BOF slag.