| 摘要 |
PURPOSE:To accelerate effectively dephosphorization reaction by blowing simultaneously a dephosphorizing agent under the bath surface of molten iron with an inert gas as a carrier gas while blowing O2 under the bath surface of the molten iron, respectively through an immersion lance. CONSTITUTION:Molten iron is desiliconized on the outside of a converter prior to converter refining and the slag formed at that time is removed. Gaseous oxygen 4 is blown through an immersion lance 3 under the bath surface of the molten iron 2 after the above-mentioned desiliconization in a molten iron ladle 1; at the same time, quicklime 6 as a dephosphorizing agent is blown under the bath surface of the molten iron 2 with N2 5 as a carrier gas. The lance 3 in this case is immersed under the bath surface of the molten iron, more preferably >=500mm. depth. O2 is blown preferably at 0.03-0.5Nm<3>/min flow rate per ton of the molten iron. The more effective dephosphorization reaction is performed by adding mill scale 7 further onto the bath surface in the above-described dephosphorization treatment. |
