| 摘要 |
Described is a fluidized-bed method of directly reducing a particulate iron oxide-containing material, the iron oxide-containing material being first reduced in at least one preliminary-reduction stage (7) by reducing gas and subsequently reduced to iron sponge in a final-reduction stage (8). The reducing gas is constituted, in part, by freshly supplied reducing gas and by the top gas produced during the reduction of the iron-containing material and is introduced in the final-reduction stage (8) where it reacts, is drawn off, and part of it is introduced in at least one preliminary-reduction stage (7) where it reacts, is drawn off, is scrubbed and is finally used as top gas, the rest being split off, scrubbed, the CO2 removed and the gas then heated and also used as reducing gas. In order to ensure that the reaction proceeds without the fluidized bed "sticking", by minimizing the amounts of hydrocarbon carriers used to generate the reducing gas, fresh reducing gas is produced from synthesis gas, and all the reducing gas which is fed to the final-reduction stage (8) is conditioned chemically in a single conditioning stage (19; 15), the CO2 removed and the gas subsequently heated. |
