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.