| 摘要 |
PURPOSE:To decrease watt loss and to improve iron yield by charging molten iron which is beforehand subjected to desiliconization, dephosphorization and desulfurization treatments into a converter, and controlling the ratio between the intrusion depth of the jet of oxygen in the steel bath and the depth of the steel bath at below specific values without adding any slag making agent or with addition of a small amt. thereof. CONSTITUTION:Molten iron which is subjected to pretreatments of desiliconization, dephosphorization and desulfurization is charged into a composite blowing furnace 1t, and without addition of any slag making agent or after a small amt. of the slag making agent of about <=20kg per ton of the molten iron is added, a lance 3 is inserted vertically through the top opening of the converter, and gaseous oxygen is blown into the molten iron through the lance 3, whereby oxygen blowing is accomplished. At this time, the ratio of the intrusion depth L of the oxygen jet from the lance 3 into the steel bath and the depth Lo of the steel bath is so controlled as to be <=0.2. |
