To efficiently remove sulfur contained in desulfurization slag, in order to utilize the desulfurization slag produced in the desulfurizing treatment of molten iron in a recycling manner.
This method for removing sulfur from desulfurization slag includes: a first step of heating the desulfurization slag in an atmosphere where an atmospheric temperature is in the range of 1,100 to 1,400°C and CO/CO2 ratio in the atmosphere is adjusted so that oxygen gas partial pressure (PO2) defined in formula (1): PO2=(PCO2/PCO)2×[1/exp(-ΔG/R×T)] lies in the range of 10-3 to 10-9 atm, and removing the sulfur in the desulfurization slag to the gas phase side of the atmosphere as SOx; a second step of applying a desulfurization treatment to exhaust gas containing the SOx removed to the gas phase side in the first process; and a third step of recycling the desulfurization slag in which the sulfur content is reduced by the first step as a CaO source in the pig iron making step or a steelmaking step.
KIKUCHI NAOKI
MIKI YUJI
Kazuhiro Mori