Experimental Study On Flotation And Semi-industrial Continuous Separation Of Fine-grained Cassiterite

Tin is an indispensable green metal in modern industry with the wide application prospect.In recent years,with the continuous mining of mines,the mineral resources of high quality cassiterite are gradually scarce,the ore selection grade is getting lower and lower,and the selection technology is becoming more and more difficult.Wenshan Dulong ore area is one of the three famous cassiterite polymetallic sulphide deposits in China.In the field production,the tailing of spiral chute is mixed with a large number of fine-grained cassiterite,which results in the waste of resources.In this paper,the recovery of fine-grained cassiterite by flotation process was studied and the semi-industrialization experiment was carried out.In this paper,chemical element composition analysis,mineral composition analysis,mineral occurrence state analysis,mineral dissociation characteristic analysis,particle size analysis and other technological mineralogy are studied.As the results,the content of valuable metal tin is 0.21%,sulfur is 3.06%,the main tin ore in the ore sample is cassiterite,-0.037 mm is 84.03%,the degree of dissociation is high,the gangue minerals are mainly chlorite,biotite,quartz and so on,the symbiotic relationship is complex,cassiterite is mainly fine-grained embedded in gangue minerals or inlaid along the edge of gangue minerals.Through flotation test comparison,product particle size analysis and tailing water sample test YK-3,it is proved that YK-3 enrichment and recovery of sulphide minerals,some fine mud is removed,and the concentration of unavoidable ions in slurry solution is reduced,so as to optimize the flotation environment of cassiterite and improve the recovery rate of concentrate.On the basis of this,the suitable flotation reagent system was obtained by the test of cassiterite desulphurization and floating tin:the YK-3dosage was 40 g/t;Na₂CO₃ the dosage was 200 g/t,KT-51 the dosage was 600 g/t,the mixed collector dosage was 1600 g/t,P86 the dosage was 80 g/t.In the closed circuit test,the sulfur concentrate with grade of 24.835%and recovery rate of 91.77%were obtained,and the tin concentrate with grade of 2.606%and recovery rate of 54.28%were obtained.In order to explore the applicability of the new pharmaceutical and flotation process enrichment and recovery of fine-grain cassiterite industrial production,a semi-industrial continuous selection test was conducted.After gradual optimization,it was determined that the desulfurization operation was"one coarse,one fine,three sweeps",and the cassiterite selection operation was"one coarse,one fine,three sweeps"as the flotation process.In the desulfurization operation,the dosage of YK-3 agent is 40g/t;in the cassiterite separation operation,the dosage of sodium carbonate is 200g/t,the dosage of KT-51 is 600g/t,the dosage of collector is 1500g/t,and the dosage of P86 is40g/t.The feed concentration of sulfur removal operation is 40%,and the concentration of cassiterite separation operation is 45%.The final tin concentrate grade in the YK-3group test was 1.249%,and the recovery rate was 50.20%.Based on the results of multiple consecutive selection tests,the flotation indicators of the YK-3 group were significantly better than the test results of the same batch of concentrated sulfuric acid and DF-336 agent combination.The high tin loss in tailings of semi-industrial re-election test was studied.Through screening test,it was proved that the process of sulfur removal operation"one coarse one sweep"and cassiterite flotation"one coarse one sweep"can make the Sn grade of tailings less than 0.1%,and the separation of 0.074 mm grain minerals can improve the recovery rate of cassiterite,effectively reduce the tin content in the tailings and meet the field production demand.