Method of smelting reduction of ores containing metal oxides
AssigneeKawasaki Jukogyo Kabushiki Kaisha
InventorsTakuya Maeda, Keikichi Murakami, Tsutomu Yamada, Mitsuharu Kishimoto, Kenichi Yajima
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Abstract
Metal oxide ore is subjected to smelting reduction to obtain the molten metal by a method which comprises prereducing said ore in solid state in a prereduction furnace, thereafter melting said ore and carrying out final reduction thereof in a smelting reduction furnace, and at the same time introducing gas generated in said smelting reduction furnace and having reductive capability into said prereduction furnace, the rate of prereducing said ore in said prereduction furnace being controlled at a value with a maximum of the order of 33 percent for raising the rate of utilization of energy to a maximum limit.
Claims8
A method of smelting reduction of iron oxide ore, comprising the steps of:
- prereducing said ore in a solid state in a prereduction furnace;
- thereafter melting said ore and carrying out final reduction thereof in a smelting reduction furnace to generate a gas having a reductive capability in the smelting reduction furnace;
- subjecting said gas to a secondary combustion at a combustion rate of 25% or more in the smelting reduction furnace;
- introducing the gas thus subjected to the secondary combustion into said prereduction furnace;
- and
- controlling the rate of prereducing said ore in said prereduction furnace to be maintained at a value smaller than 30 percent.
Dependencies are inferred from the claim text.