Experimental Study On Flotation Separation Of Linfen Copper-lead Mixed Concentrate

Most sulfide copper-lead ores have the same floatability,so it's hard to separate.In this paper,a study on the beneficiation of copper and lead mixed concentrate obtained by bulk preferential flotation in a polymetallic sulfide ore deposit in Lincang.The mechanism of action was discussed through the experiments about the adsorption capacity on the ores and the change of ores' recovery rate under different agents.On this basis,the copper-lead mixed concentrates were studied,the appropriate pharmaceutical system has been formulated to realize the effective separation of copper-lead mixed concentrates.In the chalcopyrite and galena single mineral experiments,the selective capture of ethyl thiourea shows obvious advantages in the four collectors on chalcopyrite.When pH>8,the recovery rate of chalcopyrite did not change significantly,while galena has significantly reduced when use ethyl thiourea as the collector of copper and lead separation flotation.And with the drug concentration changing,the adsorption capacity of ethyl thiourea on chalcopyrite is much than that on galena,which proved ethyl thiourea has obvious selective capture effect on chalcopyrite.The mixed agent of sodium thiosulfate + soluble starch was used to be the depressor of lead in the separation of copper-lead flotation,the inhibitory effect is significantly better than used alone.Within the concentration range of the agents test,the use of the mixed depressor will significantly reduce the adsorption capacity of ethyl thiourea on the surface of the galena,galena' s recovery rate changed significantly,while the recovery of chalcopyrite has no obvious change.Compared with the potassium dichromate which is the traditional depressor of lead has less harmful to the environment.The best match of the mixed depressor of sodium thiosulfate:soluble starch is 2:1.A mixed copper and lead concentrate with the ration of 2:1 has been taken flotation separation test in Lancang after grinding and sodium sulfide exfoliation on the basis of the single mineral test,using sodium thiosulfate + soluble starch as a galena depressor,ethyl thiourea as a collector,after the one roughing-four cleaning-three scavenging closed circuit flotation experiments,ultimately achieved the copper concentrate with the copper grade of 18.13%,lead grade of 4,65%,copper recovery rate of 82.35%and lead concentrate with the lead grade of 43.80%,copper grade of 1.83%,lead recovery rate of 95.25%.