Method for producing high-strength steelmaking slag, method for producing civil engineering materials, and method for producing slag

摘要

PROBLEM TO BE SOLVED: To stably and reliably obtain steelmaking slag of high compression strength and to obtain the high compression strength only by controlling the items confirmed by slag analysis. SOLUTION: This steelmaking slag is generated in a steelmaking process, therein, the preparation of compounding composition of slag making material of a converter, etc., the control of blowing refining, the control of flow rate of bottom blowing gas and so on are performed so as to satisfy three conditions of (1) 1.2 = slag basicity (T.CaO/SiO2 )=6.0, (2) the content of unslagged calcium oxide(F.CaO)=20 wt.% and (3) the content of coarse grained iron (4 mm) 2 wt.% and 0.1 wt.% = the content of fine grained iron (=4 mm)=5 wt.% and, as need, two nconditions of (4) the content of fluorine (F)=3 wt.% and (5) 0.1 wt.% = the content of titanium oxide(TiO2 )=5 wt.%. Thereby, the steelmaking slag which has a compression strength index more than 1.0 (the minimum value of JIS standard of uniaxial compression strength+20%=141 N/cm2 ) can be obtained.