Method for reducing chromium containing raw material
AssigneeKobe Steel, Ltd.
InventorsHiroshi Sugitatsu, Hidetoshi Tanaka, Takao Harada, Itsuo Miyahara, Isao Kobayashi
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Abstract
An object of the present invention is to provide a method for reducing a chromium-containing material at a high chromium reduction degree. In the method of the present invention, a mixture of a feedstock containing chromium oxide and a carbonaceous reductant is heated and reduced by radiation heating in a moving hearth furnace. The average rate of raising the temperature of the mixture in the reduction is preferably 13.96° C./s or higher in the period from the initiation of the radiation heating of the mixture until the mixture reaches 1,114° C.
Claims15
A method for reducing a chromium-containing material, comprising:
- mixing a chromium-containing material comprising chromium oxide and iron oxide and a carbonaceous reductant to provide a mixture;
- charging a carbonaceous atmosphere-adjusting agent together with the mixture to a moving hearth furnace;
- and
- heating and reducing the mixture with a rapid temperature rise by radiation heating in the moving hearth furnace to provide a reduced mixture,
- wherein the carbonaceous atmosphere-adjusting agent is a different material from the carbonaceous reductant, and
- wherein the average rate of raising the temperature of the mixture in said reducing is 13.6° C./s or higher in the period from the initiation of the radiation heating of the mixture until the mixture reaches 1,114° C.
A method for reducing a chromium-containing material, comprising:
- mixing a chromium-containing material comprising chromium oxide and iron oxide and a carbonaceous reductant to provide a mixture;
- charging a carbonaceous atmosphere-adjusting agent to a moving hearth furnace and then charging the mixture to the moving hearth furnace;
- and
- heating and reducing the mixture with a rapid temperature rise by radiation heating in the moving hearth furnace to provide a reduced mixture,
- wherein the carbonaceous atmosphere-adjusting agent is a different material from the carbonaceous reductant, and
- wherein the average rate of raising the temperature of the mixture in said reducing is 13.6° C./s or higher in the period from the initiation of the radiation heating of the mixture until the mixture reaches 1,114° C.
Dependencies are inferred from the claim text.