A metal sulphides ore deposits, with a variety of valuable elements, silver, gold, copper, lead, zinc and other valuable elements having multiple, silver and disseminated forms of fine particle size characteristics, sorting separation difficult. Silver minerals exist in the form of silver ore, natural silver, silver gold, gold and silver, and quite a few are encapsulated in lead and copper minerals. At present, the overall process adopted in the field is also a route of re-selection of mixed flotation-flotation concentrate cyanide-cyanide tailings, but the leaching rate of silver is not high and only copper is recovered during cyanide flotation. The copper recovery rate is not high, and the silver recovery rate in the cyanide residue is low. To this end, the existing process and the pharmaceutical system are optimized, and a process route of preferential lead selection is added in the copper selection of cyanide slag to improve the recovery rate of copper and silver. First, the nature of the ore (1) Mineral composition Metallic minerals mainly pyrite and chalcopyrite-based, a small amount of galena and sphalerite; gangue minerals quartz and sericite. This kind of element can be used for comprehensive recycling of gold, silver and copper. Copper is mainly in the presence of chalcopyrite. The main particle size is between 0.1 and 0.05 mm, and the secondary particle size is between 0.05 and 0.01 mm. The gold is mainly in the form of natural gold. The exposed gold accounts for about half; the silver is mainly composed of natural silver and sulfur. Silver exists. (II) Multi-element analysis of raw ore The results of multi-element chemical analysis of raw ore are shown in Table 1. (III) Phase analysis of copper, gold and silver The phase analysis results of copper, gold and silver in the ore are shown in Table 2, Table 3 and Table 4, respectively. Second, research methods In the mixed flotation test, the sample was taken 1.0 kg each time, and lime was used as an inhibitor of pyrite. In order to enhance the inhibitory effect, lime was added to the ball mill . The flotation equipment is carried out in a pneumatic hanging trough flotation machine according to the concentration. The flotation reagents butyl xanthate and butyl ammonium black medicine are all industrial grade standards. The cyanide leaching of the flotation concentrate is carried out in an XFT stirred leaching tank. Each test takes 100 g of concentrate, the lime and sodium cyanide used are both industrial grade standards, and the aids are analytically pure. The equipment used in the comprehensive recovery test of cyanide tailings flotation is the same as the mixed flotation. Each sample is taken 500g, and the rough selection is carried out in a 1.5L flotation tank. The chemicals used in the test were lime, ethyl xanthate, butyl xanthate, 2# oil, and sodium cyanide, all of which were of analytical grade, zinc sulfate and activator. The reagents used in the test were added to the desired location according to the concentration required for the test, except for the lime. Third, the test and results (1) Mixed flotation test Through the grinding fineness test, the collector type and dosage test, the coarse concentrate re-grinding and re-election test, etc., it is determined that the grinding fineness of the ore section is -0.074mm, accounting for 60.5%, coarse concentrate Re-grinding and re-selecting fineness -0.074mm accounted for 87.5%. The flotation agent used conventional chemicals namely lime, butyl xanthate and butyl ammonium black drug. The dosage and mixed flotation process are shown in Figure 1. The test results are shown in Table 5. The results of multi-element chemical analysis of the obtained flotation concentrate are shown in Table 6. (2) Cyanide leaching test of flotation concentrate 1. The effect of fineness of grinding on the leaching rate of silver and gold. The leaching test was carried out on the fineness of different grindings by conventional cyanidation. The solid solution ratio of the leaching solution was 2, the leaching time was 24 h, the pulp pH was 10-11, and the sodium cyanide concentration was 0.082 mol/L. The test results are shown in Fig. 2. It can be seen from Fig. 2 that the leaching rate of silver and gold increases with the increase of grinding fineness, but when the grinding fineness reaches -0.037mm, accounting for 87.5%, the grinding fineness silver and The leaching rate of gold is basically stable. Therefore, the fine grinding fineness in this test is -0.037mm, accounting for 87.5%. 2. The effect of leaching time on the leaching rate of silver and gold. The grinding fineness -0.074mm accounted for 87.5%, the leaching solution solid ratio 2, the pulp pH=10-11, the sodium cyanide concentration 0.082 mol/L, and the leaching time were 24,36,48,72 h, respectively. 3. It can be seen from Fig. 3 that with the increase of leaching time, the leaching rate of gold has little effect, ranging from 91% to 92%; when the leaching of silver increases with time, the leaching rate increases, but after leaching time is 48h. The leaching rate did not increase much. At this time, the silver leaching rate was 77.16%, so the leaching time was better in this test for 48 hours. 3. The optimal test for cyanidation leaching. Since the leaching speed of silver is slower than that of gold according to the analysis of leaching kinetics, and the leaching rate is not high, the flotation concentrate is tested after determining the optimum grinding fineness and leaching time. The initial sodium cyanide concentration, the slurry solid ratio and the slurry pH value, and the amount of the infusion agent were tested. The final test conditions are shown in Table 7. The test results are shown in Table 8. It can be seen from Table 7 and Table 8 that in the process of cyanide leaching, copper also elutes with gold and silver, which is also the cause of large cyanide consumption during cyanide leaching. (III) Copper recovery test for cyanide tailings A number of analyses were performed on the above cyanide tailings, in which the grade of copper was 3.8%. In addition, it was found that only 0.062% of the ore grade in the lead grade was subjected to flotation and enrichment, and the lead grade of the concentrate also reached 1.41%. This part of lead will float out before flotation, which will affect the lead requirement in copper concentrate. To reduce the quality of copper concentrate. Therefore, the process route of floating lead and then floating copper is determined. The phase analysis of copper cyanide residue was carried out, and the results are shown in Table 9. It can be seen from Table 9 that the copper in the cyanide residue is basically in the form of copper sulfide. In addition, the cyanogen residue is microscopically identified, and the results show that the copper is mainly chalcopyrite, and most of the monomers are dissociated. In addition to the type and amount of inhibitors in the cyanide tailings, the types and dosages of the collectors for lead selection and the activators and collectors for copper selection were tested. The process flow and pharmaceutical system are shown in Figure 4, and the test indicators are shown in Table 10. Fourth, the conclusion (1) In order to make full and rational use of copper-bearing silver-gold ore, the process of flotation-concentrate cyanide-cyanide residue preferentially selecting lead and then floating copper can obtain a comprehensive recovery rate of gold of 80.80% and a comprehensive recovery rate of silver of 81.32. %. In addition, a lead concentrate with a grade of 21.46%, a recovery rate of 82.29%, a copper concentrate of 45.00%, and a recovery rate of 69.31% can be obtained. (2) In the cyanide leaching process of concentrate, the addition of the aiding agent can increase the leaching rate of silver. In the cyanide residue after the effective recovery of silver and gold, the flotation method is used to effectively recover copper and lead, and the silver is also recovered, so that the mine can be more rationally applied. references [1] Dai Xinyu, Yu Kexu. Beneficiation test study to improve the comprehensive recovery rate of a silver polymetallic ore [J]. Comprehensive utilization of minerals, 2009 (1): 7-9. [2] Wang Baosheng, Zhang Zhenping, Liu Wanzhi, et al. Experimental study on improving cyanide leaching index of high copper and lead gold concentrates [J]. Gold Science and Technology, 2008 (5): 44-45. [3] Li Yumin, Xue Guang. Experimental study on gold and silver cyanide extraction from copper-bearing gold concentrates [J]. Nonferrous Mining and Metallurgy, 2007 (1): 17-18. filter,equipment,machinery ChangZhou FENGJU Machinery Equipment CO., LTD , https://www.czfengjumachinery.com