Study On The Combined Separation Of Lead And Zinc From Sulfur And Oxygen Mixed Lead And Zinc Ore Dressing-metallurgy

With the development of easily mined and high-grade lead-zinc ore resources in China exhausted,the development of refractory and low-grade lead-zinc ore resources has attracted more and more attention of China's mining workers.Among them,sulfur oxygen mixed lead-zinc ore resources are characterized by a wide variety of minerals,changeable ore properties,and complex symbiosis and intergrowth relationship between lead and zinc minerals and gangue minerals,which increase the difficulty of lead-zinc flotation and separation.With the increasing demand of various resources for human production and life,and the increasingly prominent global resource crisis,the efficient development and optimal utilization of oxygen sulfur lead-zinc ore has become an important issue in the field of mining and production of mineral resources.Based on the study of the ore characteristics of a newly mined low-grade lead-zinc ore in Yunnan Province,the combined process of beneficiation and metallurgy was carried out to recover lead,zinc and other valuable metals.Firstly,on the basis of consulting a large number of relevant literature,the lead-zinc mineral resources,the current situation of lead-zinc ore dressing and smelting at home and abroad,and the development status of lead-zinc ore dressing metallurgy combined process were reviewed in detail.Put forward the research background,significance and content of the paper,carry out the process experiment research,and determine the process flow.The research content of this paper is divided into two parts:the flotation process of complex sulfur and oxygen mixed lead-zinc ore and the oxygen pressure acid leaching process of sulfide lead-zinc concentrate.(1)According to the analysis of raw ore properties,the ore contains 5.01%Pb and17.62%Zn.The oxidation rate of the ore is high and it belongs to the mixed lead-zinc ore of sulfur and oxygen.Moreover,zinc and lead are tightly wrapped and difficult to separate.The paragenetic relationship of galena is complex,galena is closely distributed with other metal minerals,so it is difficult to beneficiate.(2)The experimental study on flotation process shows that the optimal process condition for flotation sulfide ore is grinding fineness-74?m content 80±5%,activator copper sulfate 300g/t,collector butyl xanthate+ethylthionitrogen(200+100)g/t;The optimal process for flotation of oxide ore is 300g/t sodium hexametaphosphate,2000g/t sodium sulfide and(200+100)g/t ammonium butyrate+butyl xanthate.Under the optimal conditions,the comprehensive recovery of lead and zinc in the mixed concentrate can reach 85.18%and 95.46%,respectively;The grade of zinc and lead in sulfide ore is 46.14%and 7.86%,respectively;The grade of lead and zinc in the oxide ore is 12.71%and 6.01%,respectively.The quality of the concentrate can meet the requirements of smelting raw materials.(3)The experimental study on oxygen pressure acid leaching of sulfide lead-zinc concentrate from flotation shows that the particle size of ore sample is-48?m content90%±15%.The results show that the optimum conditions are as follows:2%,initial acid concentration 150g/L,leaching temperature 150?,oxygen partial pressure1.3MPa,stirring rate 650r/min,leaching time 150min,liquid-solid ratio 8:1,adding 2g sodium lignosulfonate,adding 5%Fe SO₄of total leaching concentrate,the leaching rates of Zn,S and Fe are 96%,97%and 49%?57%respectively.(4)According to the research results,the reasonable combined process of beneficiation and metallurgy for extracting Pb and Zn from Complex Polymetallic lead-zinc intergrowth ore was determined.Firstly,lead-zinc oxide concentrate and lead-zinc sulfide concentrate were obtained by flotation of lead-zinc ore,and then lead-zinc sulfide concentrate was used as raw material to leach and separate lead and zinc.The combined process not only solves the problems of complex sulfur and oxygen mixed lead-zinc ore dressing and lead-zinc separation,but also effectively improves the recovery rate of valuable metals,which provides an important reference value for China's lead-zinc enterprises to deal with similar mineral resources.