| 摘要 |
PURPOSE:To reduce the steel making cost by using inexpensive lower purity oxygen during the 1st half of blowing and higher purity oxygen like a conventional process during the 2nd half in the blowing operation of an oxygen blowing converter. CONSTITUTION:In the blowing of a top oxygen blowing converter blowing oxygen into a molten steel bath 2 in a converter 1 through a lance 3, lower purity oxygen 7 contg. about 90-98% O2 is used until the molten steel 2 is decarburized to 2%> C>=1% from the early stage of the blowing. When the C content of the steel 2 reaches said value, the oxygen 7 is changed over to higher purity oxygen 4 consisting of >=99.9% O2 and <=50-100ppm N2. Thus, inexpensive lower purity oxygen can be used in place of part of higher purity oxygen without increasing the N2 content of molten steel, so the steel making cost can be reduced. By applying this method to the blowing of a bottom blowing converter and a top and bottom blowing converter, a similar effect can be produced. |
