Research And Practice Of Key Benefication On No.100 And No.105 Ore Body Of Dachang Tin-polymetallic Deposit

Dachang Tin-polymetallic ore field is located in the northwestern part of Guangxi.No.100 and No.105 ore body of Dachang Tin-polymetallic deposit should be a ore body from everywhere,and sets up and testifies the new viewpoint.No.100(105)ore body of the Dachang mine is rich in Sn,Zn,Pb,Sb,Ag,In,Cd and Au,which are of great comprehensive recovering value.In this thesis,the beneficiation of No.100 and No.105 ore body of Dachang tin-polymetallic deposit was studied.The beneflcation flow was designed,revised,and practical experiments were carried out.Based on the flotation theory of sulfide minerals,the mechanism of sulfide flotation and its practical application was studied.The flotation tests of jamesonite,marmatite,pyrite and pyrrhotite were performed.The relationship of pulp potential and the pulp pH value and the concentration of collector is the crux factor of flotation.The relationship between pH value and concentration of collector(C)and floatability of forth sulfide minerals,which include jamesonite,marmatite, pyrite and pyrrhotite,were discussed.When the pulp pH value range is lower than 7.0,sulfide minerals haves well floatability.When the pulp pH value is above 12,the pyrite and pyrrhotite cannot be floated easily in the presence of CuSO₄ and xanthate used as a activator and collector respectively.The dominant parameters of sulfide mineral floatation system were ascertained.Effective recovery of the valuable minerals can be achieved by processing the ore from No.100(105)ore body using the preferential-bulk flotation flowsheet.During the process of sulfide minerals of No.100 and No.105 ore body floatation,several important parameters including pulp pH value,depressers,collectors,flotation time and the flow structure were controlled and adjusted.Through the thermodynamic calculation,the Eh—pH equilibrium of jamesonite,marmatite,pyrite and pyrrhotite in the absence or presence of collector were set up.In acid solution,the oxidative product is neutral sulfur but S₂O₃^2-ion,Fe(OH)₂ etc.The Voltammogram measurement showed that the products formated by the surface oxidation of sulfide minerals were different,and the processes of the reaction were in keeping with the calculation results of the E—pH equilibrium.The cassiterite slime of Dachang industry contains a variety of sulfide minerals and gangues including quartz and calcite.A little of the ore particles of slime are minor than 10μm,in which the content of tin is large.Theory analysis and flotation test of slime,mineral and mixed ore were carried out in this thesis.A new kind of the collector of benzohydroxamic(SR),and the depressant of quartz and calcite and P86 were used in flotation separation of cassiterite from slime.It was shown that benzohydroxamic is a stronger collector for cassiterite,and the pH range of efficient flotation for cassiterite is much wide.P86 can improve the interaction of benzohydroxamic with cassiterite,and it reduce the consume of benzohydroxamic in flotation processing.The adsorption mechanism of benzohydroxamic on cassiterite was studied by the determination of the infraed spectra,zeta potential measurement.It was indicated that benzohydroxamic is chemically adsorbed on the surface of cassiterite.The grade of Sn concent ate is 11.43%with the recovery of 88.72%.No.100 and No.105 ore body of Dachang is tin-polymetallic ore.In the new process,the grinding size is controlled at - 0.25mm and the principle p rocess f low is magnetic separation flotation-gravity separation.In magnetic separation,magnetite is separated out to eliminate its effect on sulfide flotation;in flotation,the selective flotation of Pb, Sb-bulk flotation-separation of Zn from S is applied;in gravity separation, concentrating table is applied to recover cassiterite in tailings from flotation.Application of this process in Bali Mineral Processing Plant indicates that the technology is reasonable and production indexes have reached design requiremen t.When the original grade of metals were: Pb3.74%,Sb3.87%,Zn8.72%and Sn1.96%,the grade of Sn concentrate is 54.92%with the recovery of 83.72%;the Pb,Sb concentrate contains 29.13%Pb,25.49%Sb,recovery 84.78%and the grade of Zn concentrate is 445.12%w ith the recovery 82.10%.Waste water was recycled in the flow.By adding flocculate reagents with high molecular weight in the major flow,the water was purified and recycled.The recycling rate was over 100%.