| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for desiliconizing or dephosphorizing a molten pig iron with the use of a container having a small free board such as a hot-metal ladle and a torpedo car, while inhibiting an outburst of slag, shortening the treatment period of time, and enhancing the productivity even without arranging a cylindrical body for securing the free board. <P>SOLUTION: This method for refining the molten pig iron includes: top-blowing and supplying a gaseous oxygen source from one supply system provided on a top-blow lance 7; at the same time, top-blowing and supplying at least one part of a solid oxygen source 4 from another supply system provided on the top-blow lance, onto the same place as a place to which the gaseous oxygen source has been supplied or the surface of a molten pig iron bath in the vicinity of the place, by using a carrier gas; and controlling the respective amounts of the oxygen sources to be supplied so that a ratio V/F<SB>O2</SB>(kg/Nm<SP>3</SP>) of a supply rate of the gaseous oxygen source F<SB>O2</SB>(Nm<SP>3</SP>/min×t) to a supply rate of the solid oxygen source V (kg/min×t) is in a range of 0.60 to 6.0, when desiliconizing or dephosphorizing the molten pig iron 2 housed in the hot-metal ladle 5 or the torpedo car by adding the oxygen source and a CaO-based flux 3 to the molten pig iron. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
