METHOD FOR CONTROLLING BLOWING PROCESS

摘要

PROBLEM TO BE SOLVED: To make slag surely produced during blowing in a converter without using fluorite, even when byproduct slag produced in manufacturing aluminum is reused as an auxiliary material for the converter process. SOLUTION: This method for controlling a blowing process includes, using the slag by-produced in manufacturing aluminum and other components as the auxiliary materials, and adjusting formation of the above auxiliary materials so that the slag produced during blowing can satisfy the following expressions (1)-(4). A=%CaO/(%SiO2+%Al2O3+%T.Fe)=0.7-3...(1) B=%SiO2/A=3-40...(2) C=%Al2O3/A=0.7-14...(3) D=%T.Fe/A=5-27...(4) In place of adjusting the formation of the above auxiliary material, the method may include, controlling a ratio (Ps/W) of a collision pressure Ps of spouted oxygen to the mass of molten steel, as 50 Pa/t or less.