GB758956A - A continuous process for the production of sulphur, or sulphur and sulphur dioxide, from pyrites ores - Google Patents

Abstract

<PICT:0758956/III/1> A continuous process for roasting pyrites ores wherein the sulphur dioxide gases from the roasting stage pass through a solid reducing agent to reduce some or all of the sulphur dioxide contained therein to sulphur, the resulting reduced gases being contacted with fresh pyrites ore to distill the labile sulphur therefrom, the ore being then passed to the roasting stage, all said stages being accomplished in a single vessel in which the gas-solid contacts are effected by the fluidization technique. Ore is fed from 5 to the upper distillation bed 2 of vessel 1 and the resulting Fe7S8 passes through 10 to roasting bed 4. Air or oxygen-enriched air enters bed 4 at 15 to provide a stoichiometric excess of oxygen for roasting at above 1000 DEG C. The sulphur dioxide gases pass from bed 4 through bed 3 at 800-1000 DEG C., fed with carbonaceous reducing agent from 6, to reduce some or all the sulphur dioxide to sulphur. The reduced gases pass through the distillation bed 2 at 700-800 DEG C. to distil off labile sulphur from the ore. The gases leave at 16 and sulphur is condensed in cooling device 17. A portion of the sulphur dioxide gases formed may be recycled through 20 to the roasting bed for temperature control and ore may also be fed direct to bed 4 from 5. Specification 463,439 is referred to.