PROCESS FOR PRODUCING A SINTER WHICH CONTAINS WAELZ OXIDE AND IS TO BE PROCESSED IN A SHAFT FURNACE FOR SMELTING ZINC

摘要

1342006 Sinter containing Waelz oxide METALLGESELLSCHAFT AG 27 Aug 1971 [10 Sept 1970] 40354/71 Heading C1A A sinter containing Waelz oxide as hereinafter defined which is to be processed in a shaft furnace for smelting zinc is produced in a process wherein Waelz oxide is subjected to a separate step in which the Waelz oxide is simultaneously homogenized, moistened and compacted and is then added to a mixture to be sintered the mixture comprising a sulphide zinc ore or concentrate whereafter the mixture is sintered. Waelz oxide is an oxidic material produced by the Waelz process and normally having a metal content of 60 to 70% by weight. Preferably the homogenizing, moistening, and compacting step comprises a pelletizing and fuel is incorporated in the pellets. The percentage of fuel incorporated in the pellets may be lower than the percentage of fuel incorporated in the mixture to be sintered. The fuel is preferably a sulphur-containing material. The pellets may have a size up to 10 millimetres. The homogenizing, moistening and compacting step may advantageously comprise an ageing step, the mixing time used in the ageing step being longer than the mixing time used to mix the sinter mixture. The moisture content of the mixture which is being aged may amount to 3 to 20% by weight.