Metallgesellschaft Aktiengesellschaft

Fritz Rose

Martin Hirsch

Harry Serbent

Wolfgang Bresser

Bernd Kosters

In a first fluidized bed vessel containing an expanded fluidized bed, iron oxide-containing materials are reduced under weakly reducing conditions with solid carbonaceous reducing agents to or to less than the FeO state. In a second fluidized bed vessel containing an expanding fluidized bed the gas-solids suspension discharged from the first fluidized bed vessel is treated with a highly reducing fluidizing gas whereby the material is reduced in part to iron metal. From the gas-solid suspension discharged from the second fluidized bed vessel the carbonized carbonaceous material is separated and is recycled to the first fluidized bed vessel. The exhaust gas from which the carbonized carbonaceous material has been removed is purified and CO.sub.2 is removed therefrom and the exhaust gas is subsequently fed as a fluidizing gas to the second fluidized bed vessel. A reduced material which has a degree of metallization from 50 to 80% and the remainder of the carbonized carbonaceous material are discharged from the second fluidized bed vessel and in a melting reactor are completely reduced and melted.

Direct reduction of iron oxide materials with solid carbonaceous

A process is described in which iron oxide-containing materials are reduced by a treatment with a gas underpressure in series-connected fluidized bed reactors, wherein hydrocarbons are cracked to produce the fresh reducing gas, reducing gas is fed to the first fluidized bed reactor as a fluidizing gas, the gaseous effluent from the first fluidized bed reactor is dedusted and is then fed as a fluidizing gas to at least one further fluidized bed reactor is dedusted and is subsequently treated in a scrubber-cooler to remove substantially all H.sub.2 O and residual dust, purified gas is recycled as recycle gas to the first fluidized bed reactor and the iron oxide-containing materials are preheated and are subsequently fed to the last fluidized bed reactor. The hydrocarbons are cracked by an approximately stoichiometric steam stoichiometric steam reforming. The freshly produced reducing gas is fed to one or more fluidized bed reactors.

Process for reducing fine-grain iron oxide materials with a gas

Disclosed is a process for the production of reduced iron oxide-containing materials. Iron oxide and solid carbonaceous reducing agent are charged into a first expanded fluidized bed, which is supplied with an oxygen-containing fluidizing gas. The gas residence time selected is controlled in the reactor containing the first fluidized bed so that the reduction potential will result in a reduction of the iron oxide material not in excess of the FeO stage. A gas-solids suspension discharged from the first fluidized bed is supplied to a second expanded fluidized bed, which is supplied with a strongly reducing fluidizing gas. Strongly reducing gas and a major portion of the resulting devolatilized carbonaceous material are discharged from the upper portion of the second fluidized bed. Reduced material having a metallization of 50 to 80% and the remaining devolatilized carbonaceous material are discharged from the lower portion of the second fluidized bed.

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Bad Homburg, Germany

Fritz Rose