The Research On Flotation Of Complex Cu-Au-S Polymetallic Ore

Along with the development of the national economy more and more quick, the demands for copper and gold have also grown than a day for a day. But after decades of consumption, the mineral resources remained are more complicated and grade gets lower. Therefore, in order to alleviate supply&demand contradiction, it’s of vital importance to develop technologies that can recover valuable minerals from complicate multi-metal ores selectively and comprehensively.Thus, researches on flotation separation of chalcopyrite and pyrite were carried out by the author. Several collectors are chosen to study their influence on the flatation behavior of chalcopyrite and pyrite, such as sodium butyl xanthogenate, Y-89xanthogenate, ammonium-butyl aerofloat, PZA and combination of sodium butyl xanthogenate&PZA. The results showed that in lower alkaline solution, PZA has preferable selectivity for chalcopyrite. PZA, used together with sodium butyl xanthogenate, can achieve a amazing efficiency of collecting chalcopyrite.According to the results of processing mineralogy of the ore conducted in this study, the ore contains1.33%copper,1.98g/t gold, copper mainly exists in the formation of chalcopyrite, with lean fine dissemination size, while gold mainly exists in the formation of native gold, with extreme fine dissemination size. Meanwhile, it’s contains large amounts of pyrite, up to22.12%, and it also contains some magnetic pyrite of good floatability.Based on the property of the ore, the flowsheet of "Cu-S bulk flotation, bulk concentrate regrinding, Cu-S separation" was recommended. Several essential tests, containing grinding fineness, collector type and dosage, the amount of lime, were conducted to determine their influence on floatation efficiency. Those experimental tests proved stage grinding&stage separation, and combination of PZA and butyl xanthogenate can achieve satisfying floatation indexes. The final copper concentrate contains22.87%copper with93.54%copper recovery and19.98g/t gold with51.50%gold recovery respectively, while the sulfide concentrate contains42.02%sulfide with66.15%sulfide recovery and2.86g/t gold with29.16%gold recovery respectively. Laboratory testwork in this study can laid theoretical and technical basis for highly efficient separation of such kind of ore.By determining adsorption amount and acquiring infrared spectrum the interfacial mechanism between collectors and chalcopyrite&pyrite were studied. The measuring test indicated that PZA adsorbed on chalcopyrite chemically while physically adsorbed on pyrite. In addition, by calculating of collector molecular properties, such as group electronegative and HMO, and the reason accounts for high selectivity of PZA has been expounded in this paper.