| 摘要 |
PURPOSE:To improve the heat deposition efficiency by the secondary combustion of the gas formed by reaction by adjusting the ratio between the depth of a recess and the radius of a vessel to a specific value at the time of forming said recess by a rotating magnetic field on the surface of the molten metal in the vessel and supplying raw material ore, carbonaceous material and gaseous oxygen for refining therein to reduce the raw material ore. CONSTITUTION:The molten iron 1 in the vessel 2 is rotated by a rotating magnetic field generating device 3 to form the recess in the central part. The ore, carbonaceous material etc., are thrown into the molten flag 7 in the recess and the gaseous oxygen 6 is blown from a lance 5 therein to reduce the ore and to recover the iron-component contained therein into the molten iron. The depth of the recess is adjusted to attain >=0.5h/r when the depth of the recess of the above-mentioned molten iron is designated as (h) and the radius of the vessel 2 as (r) in this case. The heat deposition efficiency of the heat formed when the CO-contg. gas generated by the reduction reaction makes the secondary combustion by O2 is improved and the erosion by the excessive heating of the refractories of the vessel is prevented. The ore is thus melt-reduced with the excellent thermal efficiency. This method is usable for refining of ores of Mn, Cr, etc., as well.
|
