| 摘要 |
PURPOSE:To improve secondary combustion efficiency even if the molten slag and molten metal in an oxygen top blown converter having bottom tuyeres fluctuate by freely vertically movably provided plural pieces of splash lances in addition to a main lance for oxygen blowing to said converter. CONSTITUTION:The plural splash lances 10 are freely vertically movably attached around the oxygen feed lance 3 to the converter 1 having the oxygen feed lance 3 made into the double construction having a passage for oxygen, coke powder, etc., and passage for oxygen for secondary combustion and having the tuyeres 4 for charging the powder of raw material ore and carbonaceous material as well as Ar, O2, process gas, etc., in the stage of charging molten iron, Cr iron, etc., into the converter and producing a molten steel and high-Cr steel by oxygen blowing. Oxidizing gas, Ar, N2, process gas, etc., are blown from such splash lances 10 into the converter to splash the molten slag 5 if said slag is too large in amt., by which the secondary combustion heat generated by the oxidation decarburization refining of the molten metal 2 in the space above the molten slag 5 is effectively transferred to the molten metal 2 and the combustion heat of CO is efficiently utilized. |
