| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for refining molten iron, with which the blending ratio of cold-iron source, such as iron scrap, can be improved under the condition of excellent thermal efficiency and productivity, without the risk of the heat generation and combustion in the flow path in a top-blowing lance, when the molten iron is subjected to a dephosphorizing treatment or decarburization refining in the converter while forming the flame with a burner at the tip part of the top-blowing lance and supplying the heat of the flame into the molten iron.SOLUTION: A top-blowing lance 3, respectively and separately having a powder supplying flow path for refining, an oxidizing gas supplying flow path for combustion and an oxidizing gas supplying flow path for refining, is used. Then, from the powder supplying flow path for refining, the powder 29 for refining of one or more kinds among lime-series flux, iron oxide and combustible material, are supplied toward the molten iron bath surface with fuel gas or the mixed gas of the fuel gas and inert gas as gas for conveying. Further, the flame is formed at the tip and lower side of the top-blowing lance by supplying oxidizing gas from the oxidizing gas supplying flow path for combustion, and oxidizing gas is supplied toward the molten iron bath surface from the oxidizing gas supplying flow path for refining. |
