Effects of Temperature and Oxygen Potential on Removal of Sulfur from Desulfurization Slag

The effects of temperature (1373-1673 K) and oxygen potential on removal of sulfur from hot metal desulfurization slag were investigated in laboratory-scale experiments. Both CaS and CaSO4 exist as sulfur compounds in hot metal desulfurization slag. CaS can be removed under the condition of higher oxygen potential, whereas CaSO4 can be removed at a lower oxygen potential. Thus, in order to remove both CaS and CaSO4 from desulfurization slag, it is important to control the temperature and oxygen potential to the optimum values. In this study, a higher sulfur removal ratio exceeding 90% was obtained under the conditions of a temperature range of 1473-1673 K and oxygen potential range of 10–3-10–8 atm. These results were in good agreement with thermodynamic calculations.