Free CaO stabilisation by mixing of BF slag and BOF slag in molten state

Abstract

ABSTRACTReducing free CaO (f-CaO) in basic oxygen furnace (BOF) slag effectively and efficiently is the prerequisite to achieve the goal of BOF slag's volume stability. In this work, Taguchi experimental design method was used to explore the influencing factors effect on stabilising f-CaO by mixing BOF slag with blast furnace (BF) slag and probe into the relevant mechanism. The results show that, in the setting conditions of this work, the most influential factor on the stabilisation ratio of f-CaO is mass ratio between BF slag and BOF slag, and then mixing temperature and duration time as a queue. The reasonable conditions are obtained as follows: mass ratio of BF slag to BOF slag is 6:1, temperature of mixing is 1783 K and duration time for mixing is 20 min. The f-CaO stabilised mechanism on BF slag and BOF slag molten mixing was regarded as mutual coupling effects of stabilisation reactions and dilution.