| 摘要 |
PURPOSE:To desulfurize molten iron efficiently and to prevent the resulfurization from slag to molten metal by controlling the basicity of molten slag by using Na2CO3 then blowing powder of CaC2 through a lance pipe into the molten iron. CONSTITUTION:A basicity control agent consisting essentially of Na2CO3 is added to the molten slag floating on the surface of molten iron to control the basicity of the slag expressed by {(CaO%)/56+2(Na2O%)/62}/(SiO2%)/60 to >=1.7, thence desulfurizing powder consisting essentially of CaC2 or CaC2 is blown into the molten iron together with a nonoxidative gas through a lance pipe at the constant speed selected within a 0.1-0.3kg/min. per ton of molten iron expressed in terms of CaC2, so that when the concn. of the sulfur in the molten iron decreases within a 0.013-0.023% range, the blowing speed of the desulfurizing agent powder is decreased to half the above-mentioned speed or below. |
