PURPOSE: To refine efficiently a large amt. of ferrous cold charge and to produce a molten steel having good quality by subjecting the preliminarily treated molten iron obtd. by oxygen blowing of a molten iron, a large amt. of ferrous cold charge and carbonaceous material in one of two kinds of converters to oxygen blowing in the other converter.
CONSTITUTION: A molten iron 5 such as molten pig iron, molten iron of electric furnace, reed molten metal of preliminarily treated molten iron 2', a relatively large amt. of ferrous cold charge 6 such as scrap, cold iron and a carbonaceous material 7 such as coal, coke are charged into the 1st converter 1 or blown through tuyeres therein and are subjected to oxygen blowing A in a process (a). The resulted molten iron 2 is partly left in the converter 1 and is transferred into a ladle 8. Scrap 6' and carbonaceous material 7' are again charged into the converter 1 and oxygen blowing B is executed again; further the molten iron 2 is subjected to oxygen blowing in the stage C and is transferred into a ladle 9. The preliminarily treated molten iron 2 of high carbon obtd. by the above-mentioned stage (a) is charged into the 2nd converter of the stage (b) except part 2' to be returned as a seed molten metal to the 1st converter 1 and is subjected to oxygen blowing. A molten steel 4 of low P and S is discharged into a ladle 10.
FUJII TETSUYA
KATOU YOSHIHIDE
YAMADA SUMIO
EMOTO KANJI
| JPS5881909A | 1983-05-17 |