| 摘要 |
<p>1,222,123. Reducing iron oxide to produce sponge iron. METALLGESELLSCHAFT A.G. April 30, 1968 [May 27, 1967], No. 20491/68. Heading C7D. Sponge iron is produced by directly reducing materials containing iron oxide with carbonaceous reducing agents, e.g. coal or lignite, without melting, e.g. at 1000-1250‹C., in a rotary kiln provided with shell pipes or burners, the reducing agent being continuously fed into each section of the reducing zone of the rotary kiln, in the same direction as the gas flow, so as to be distributed on to the charge bed surface, the feedrate being sufficient to replace the reducing agent consumed in that section and maintain in each section the amount of reducing agent present in the material discharged from the kiln, preferably 2-15% of the iron oxide, sufficient to prevent reoxidation of the iron produced. This amount is preferably separated from the sponge iron discharged and returned into the kiln. A sulphur-binding material, e. g. limestone or dolomite, may be added to the charge which is preferably preheated to the reduction temperature before charging.</p> |
