Desulfurization Behavior and Mechanism of CaO-saturated Slag

To develop a high-efficiency desulfurizer for the production of pipeline steel with the LD-RH-CC process, the desulfurization efficiency and mechanism of CaO-saturated slag were studied using a vacuum-induction furnace and Si-Mo electric resistance furnace. The results show that the desulfurization ability for slag with a small amount of solid CaO was highly enhanced under conditions of satisfied kinetics. The desulfurization reaction of CaO-saturated slag depended on the liquid slag rather than the solid CaO, as sulfur was not detected inside the solid CaO. The desulfurization efficiency of CaO-saturated slag was also influenced by the amount of residual liquid slag and its sulfur absorption ability. The sulfur absorption ability of CaO-CaF2 slag was analyzed to be much higher than that of CaO-Al2O3-CaF2-(SiCO2) slag. Moreover, the effect of solid CaO on the desulfurization kinetics was evaluated and the application conditions of CaO-saturated slag were discussed.