Effect of Iron Oxide on Sulfide Capacities of CaO–SiO₂–FeO and CaO–Al₂O₃–FeO Ternary Systems

Towards steelmaking processes which are compatible with the sustainable society, re-sulfurization reaction in hot metal pre-treatments needs to be suppressed as much as possible. To evaluate the effects of iron oxide on the sulfur distribution ratio between FeO-containing slag and hot metal, sulfide capacities and FeO activities were measured in CaO–SiO₂–FeO and CaO–Al₂O₃–FeO ternary liquid slags. Although the FeO activity and oxygen potential increased, the addition of FeO raised sulfide capacity drastically and resulted in an increase in the calculated value for distribution ratio of sulfur.