| 摘要 |
PROBLEM TO BE SOLVED: To provide a refining method for a converter which can reduce the dust generation rate while keeping high decarbonization oxygen efficiency, in decarbonization refining of molten iron by top-blowing an oxidative gas.SOLUTION: In removing carbon in molten iron, through oxidation, by blowing an oxidative gas onto the surface of molten iron in a converter from a top-blowing lance arranged, at its tip, with a Laval nozzle or a straight nozzle with an outlet diameter D(mm) and a throat diameter D(mm) meeting a condition D≥D, a top-blowing lance is used which includes a Laval nozzle or a straight nozzle having four holes arranged around the central axis of the top-blowing lance and each having the central axis with an inclination angle to the central axis of the top-blowing lance being 18-22°. |
