METHOD FOR MODIFYING STEEL SLAG AND METHOD FOR MANUFACTURING STEEL SLAG

摘要

PROBLEM TO BE SOLVED: To provide a method for modifying steel slag capable of suppressing hydration expansion by modifying the steel slag while maintaining good slag discharge property.SOLUTION: There is provided a method for modifying a slag steel 2 by blowing oxygen gas-containing gas 4 to a steel slag 2 at a molten state for 1.0 to 20 min., where one with a value represented by the formula (1) of 1 or less is used as the steel slag 2 and a value represented by the formula (2) of the slag 2 after modification is 1 or less. [T-CaO]-(1.87×[SiO]+1.43×([T-Fe]-1.55)+1.10×[AlO]+1.18×[PO]) (1). [T-CaO]-(1.87×[SiO]+0.70×[FeO]+1.10×[AlO]+1.18×[PO]) (2). [] is content (mass%) of a compound or an element in the parenthesis. There is provided a method for modifying the steel slag 2 with the amount of blowing of the oxygen gas-containing gas 4 is 8 to 26 Nm-O/t-slag in terms of oxygen content.SELECTED DRAWING: Figure 1