| 摘要 |
<p>PROCESS FOR UPGRADING IRON ORE PELLETS In a process for hardening oxidizable green iron ore pellets in a horizontal grate or a circular grate furnace, said process comprising passing the grate with a bed of pellets thereon along a horizontal path through the furnace wherein said pellets are heated by contact with hot gases, the furnace having a zone in, or downstream of, the area where the peak temperature of the furnace is attained in which zone the average pellets temperature is in the range of about 1100.degree.F to about 2200.degree.F and in which zone the flow of gases is in a downward direction towards the pellets on the grate the improvement comprising: (a) covering the periphery of at least part of the zone with at least two hoods to provide a hooded area on each side of the top of the grate under which the periphery of the grate passes; (b) passing at least one oxygen stream within each hooded area in such a manner that the stream flows in a downward direction towards and through the periphery of the bed of pellets on the grate passing through the hooded areas; (c) passing the periphery of the bed of pellets on the grate through the hooded areas in such a manner that the residence time of such pellets in the hooded areas is at least about 5 seconds. SPECIFICATION</p> |
