To effectively perform refining without removing slag when switching from a desiliconizing treatment to a desulfurizing treatment, when desiliconization and desulfurization of molten iron in a vessel are carried out by using an injection lance and an oxygen lance.
In a method for refining the molten iron, the molten iron containing ≥0.25 mass% [Si] is charged into a ladle, oxygen is blown on the molten iron in the ladle from an oxygen lance, gas for stirring and a refining agent are blown in the direction of the oxygen lance from the injection lance, and thus, the desiliconization and desulfurization of the molten iron are performed. The operational condition of the oxygen lance and the injection lance is regulated. Further, a slag composition when the refining agent is switched from a desiliconizing agent to a desulfurizing agent to perform shifting from a desiliconization treatment to a desulfurization treatment, is adjusted into the range of CaO/SiO2=0.5 to 1.0, and T.Fe≤15 mass%.
SAITO KOSUKE
SUZUKI YOSHIO
| JPS60234906A | 1985-11-21 | |||
| JPH05202408A | 1993-08-10 | |||
| JP2004292924A | 2004-10-21 | |||
| JPH08218109A | 1996-08-27 |
Mikio Yasuda