| According to the status quo that it is difficult to treat the abundant resource of marmatite with high ferrous content in our province economically by the present available hydrometallurgical process, a new technology has been developed to treat High Ferrous Zinc Sulphide Concentrate (HFZSC) . Based on the systemic laboratory and pilot experiment in full process flow, industrial test research has been carried out and the commercialization treatment of HFZSC has been brought to success, and some key technique problems in industrial application have been overcome. The steady results of industrial production show: pressure leaching is an effective, clean and economical technology to treat HFZSC.1. The mineral structure of HFZSC, the mechanisms of pressure leaching of zinc and the electron transference of iron ion have been examined systematically.2. Having no formation of zinc ferrite as in the traditional roasting technology for zinc hydrometallurgy and getting rid of the disadvantage of the presence of iron ion, the new technology could make full use of the self-catalytic function of iron in the HFZSC and the indirect help of Fe3+ for zinc leaching. Therefore the leaching effect is strengthened and leaching time is decreased in the new technology that makes what harmful in traditional zinc hydrometallurgy as here useful.3. By using HFZSC samples of the average zinc grade 42.17%( lowest to 38.95%), the average iron grade 14.39%( highest to 19.96%) and the average sulphur grade 29.20%, the continuous pressure leaching industrial study has been accomplished, and the leaching recovery of zinc is 98.06%, the total recovery of zinc is 94.25%, only 29.22% of Fe is leached into the leachate. So the selective leaching ofzinc has been achieved.4. Lead and silver minerals in HFZSC are enriched in the tailing of leaching residue flotation, the recovery of sliver could reach more than 90%. Sulphur is enriched as elementoid state in the leaching residue, and can be separated by conventional froth flotation process. The ratio of converting sulphur to elementoid state is 92.22%. The final recovery of sulphur can reach more than 80%. So the comprehensive utilization of accompanied valuable elements is of high level.5. The yield of sulphur is only 26.6% as the yield of sulphuric acid produced in traditional hydrometallurgy process. The sulphur can be treated as normal commodity for storing, packing and transportation, and its usability is more flexible. The new technology produces no SO2 and has absolutely no pollution of those waste gases produced in traditional process.6. The autoclave and its auxiliary equipment in industrial test research could meet the requirements of rigor leaching environment, such as high temperature, pressure, sulphuric acid medium, pure oxygen atmosphere, mechanical stirring and abrasion by concentrate, and the autocontrol level is high. The problem of oxygen dissolving in slurry has been solved, and the commercialization of key equipment has been realized successfully. The three phase reaction including gas(oxygen)— —liquid(leaching reagent) —solid(concentrate) has been carried out in the leaching process. It will obviously obtain economical benefit and expand the range of raw material purchasing that if enterprises use this new technology.
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