Direct reduction process for producing reduced iron
AssigneeKobe Steel, Ltd.
InventorsDentaro Kaneko, Mamoru Onoda, Yoshio Kimura, Yutaka Inada, Masahiro Tomita
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Abstract
The present invention discloses a direct reduction process for producing reduced iron by reducing iron ores and/or pellets with reducing gases, wherein the iron ores and/or pellets are reduced to a degree of reduction of 30-80% by a reducing gas containing 15-40% by volume of methane at a temperature of more than 950.degree. C. and further reduced by a reducing gas containing high proportion of carbon monoxide and/or hydrogen at a temperature of below 1000.degree. C.
Claims7
A direct reduction process for producing reduced iron by reducing iron ores and/or pellets with reducing gases in a shaft furnace comprising the steps of:
- (1) reducing the iron ores and/or pellets to a degree of reduction of 30-80% with a first reducing gas heated to a temperature of more than 950.degree. C. in a first reduction zone, said first reducing gas containing 15-40% by volume of methane, and
- (2) further reducing the iron ores and/or pellets thus reduced with a second reducing gas at a temperature below 1000.degree. C. in a second reduction zone, said second reducing gas containing a high proportion of carbon monoxide and/or hydrogen and a proportion of methane between zero and a proportion which is less than the proportion which causes heavy carbon deposition within the burden or retardation of the rate of reduction.
A direct reduction process for producing reduced iron by reducing iron ores and/or pellets with reducing gases comprising the steps of:
- (1) reducing the iron ores and/or pellets to a degree of reduction of 30-80% with a first reducing gas heated to a temperature of more than 950.degree. C. in a first reduction zone, said first reducing gas containing 15-40% by volume of methane, and
- (2) further reducing the iron ores and/or pellets thus reduced with a second reducing gas at a temperature below 1000.degree. C. in a second reduction zone, said second reducing gas containing a high proportion of carbon monoxide and/or hydrogen and a proportion of methane between zero and a proportion which is less than the proportion which causes heavy carbon deposition within the burden or retardation of the rate of reduction.
Dependencies are inferred from the claim text.