First, the nature of the ore A mineral arsenic, sulfur and copper deposit, containing ore types of secondary enrichment copper sulfide. Metal mineral content (5.9%), mainly useful for metallic minerals pyrite, blue chalcocite - chalcocite, covellite, enargite - block enargite small to trace amounts of sulfur and iron-tin copper, (arsenic) beryllium copper ore, chalcopyrite, porphyrite, azurite, etc. Among the copper minerals, the Lanhui copper deposit accounts for 0.8% of the total minerals, and the sulfur, arsenic copper ore and copper blue account for 0.2%. Pyrite is the main sulfur mineral, accounting for 4.9%. The gangue minerals are mainly quartz , accounting for 53.8%, followed by 35.2% alumite and dickite, and 11% clay minerals. The results of multi-element chemical analysis of raw ore are shown in Table 1. Table 1 Results of multi-element chemical analysis of ore Component Au/10 -6 Cu CaO MgO Ag/10 -6 As S SiO 2 Al 2 O 3 Tfe Quality score 0.16 0.58 <0.01 0.01 1.64 0.03 6.58 63.64 10.9 4.22 It can be seen from Table 1 that the main valuable components in the ore are copper, sulfur and associated beneficial components such as gold, silver , lead , zinc , tin, etc., and the harmful element is arsenic. Arsenic is mainly found in sulfur-arsenic copper ore. Except for copper and sulfur, the content of other elements did not reach the content standard for comprehensive evaluation. The ore contains 0.58% copper and is a low grade copper ore. A small amount of associated gold can be enriched in the copper concentrate and does not have to be recycled separately. The minerals in the ore are mainly coarse-grained, and the process grain size of the main copper minerals is +0.074mm, which is more than 85%. The pyrite has a particle size of 0.01 to 0.60 mm, which is mostly 0.08 to 0.40 mm, and about 75% of pyrite has been dissociated when it is broken to -2 mm. When the original ore milled to a fineness of -74m accounted for 60% to 70%, the monomer dissociation degree of various metal minerals was above 85%; however, some copper minerals were distributed among the pyrite particles, cracks and yellow. Iron ore contains or is continuously distributed, or is distributed in a star-shaped distribution between gangue minerals and is associated with gangue minerals. This part of copper-sulfur minerals has a complicated relationship. It is difficult to dissociate the monomers under rough grinding conditions, which makes separation difficult. Therefore, it is considered to be properly finely ground or mixed with fine concentrate and then ground. The phase analysis results of copper are shown in Table 2. Table 2 Results of copper chemical phase analysis in ore Copper sulphide Copper oxide total Native Secondary Free copper Combined copper Copper sulphide Copper oxide content Occupy copper content Occupy copper content Occupy copper content Occupy copper Occupy copper Occupy copper 0.02 3.5 1.41 70.69 0.11 18.97 0.04 6.84 74.19 25.81 Second, the determination of the selection process Copper sulfide is the main mineral of copper, and flotation is the main method of mineral processing . According to the nature of the ore, the main purpose of this study is to select copper, which is associated with gold recovery in copper concentrates, and comprehensive recovery of sulfur when economically feasible. The recovery of the remaining useful components is not considered at this time. Because the main copper mineral in the ore is blue-copper copper, the floatability is very good, and the size of the inlay is coarse. Therefore, by exploring the test and combining the ore process mineralogical research results, it is determined that the flash flotation after a rough grinding is adopted. Part of copper, copper and sulfur mixed after re-grinding and sorting process, under the conditions of copper minerals basically reaching the monomer dissociation, flashing high-grade easy-selection copper minerals, reducing the copper minerals caused in the middle ore circulation Loss; the remaining more difficult to float copper minerals and pyrite mixed flotation, after re-grinding copper sulfur is fully dissociated and then sorted. Third, the beneficiation test (a) a rough grinding and tailing The metal minerals in the ore are coarser in grain size, and the test results of easy monomer dissociation of different grinding fineness are shown in Table 3. See Figure 1 for the test procedure. The results show that when the grinding particle size changes between -50μm and 50%~87%, the loss rate of copper in tailings is low, and the change is not big; when the original ore is milled to -74μm, the content is 51%. The grade of copper in the mine is 0.024%, and the loss rate is only 2.66%, which can be completely discarded as qualified tailings. Therefore, a section of grinding can be used to remove tailings by coarse grinding (fineness -74μm content of 5l%). Table 3 Grinding fineness test results Grinding fineness /-74μm product name Yield Copper grade Copper recovery 42 Copper concentrate 19.72 2.8 95.2 Tailings 80.28 0.035 4.8 51 Copper concentrate 19.59 2.99 97.33 Tailings 80.41 0.024 2.66 62 Copper concentrate 18.72 3.23 96.87 Tailings 81.28 0.024 3.12 70.8 Copper concentrate 15.4 3.64 97.36 Tailings 84.6 0.018 2.64 87 Copper concentrate 16.09 3.39 97.01 Tailings 83.91 0.020 2.99 Figure 1 Copper rough selection test procedure (2) Flash floating high-grade copper mineral The Lanhui copper deposit in the ore is the main copper-bearing mineral, accounting for more than 70% of the total copper content. In addition, it also contains some arsenic-containing copper minerals. Generally speaking, the Lanhui copper mine and the sulphur arsenic copper ore are good in floatability and easy to float. This part of the floatable mineral only needs to add a small amount of selective collector , which is very short flotation time. A high quality one-step copper concentrate can be selected. Compared with the conventional copper selection scheme (see Table 4), the copper flotation recovery rate is similar, but the copper grade is higher. Table 4 Comparison of flash flotation scheme and conventional copper selection scheme Program name product name Yield Copper grade Copper recovery Flash flotation copper Copper concentrate 1.82 31.17 93.53 Conventional flotation copper Copper concentrate 2.35 23.87 93.64 (3) Flotation process conditions 1, rough selection of suitable pH The ore contains a large amount of pyrite, so lime is used as the pH adjuster for the slurry, and the addition of lime during the grinding process can also inhibit the pyrite. The amount of lime used has a great influence on the floating copper index. The effect of different lime addition on the rough copper selection test is shown in Figure 2. The test procedure is shown in Figure 1. With the increase of lime addition, the grade and recovery rate of copper coarse concentrate gradually increased, and the grade of copper coarse concentrate increased gradually, and then decreased to 1500g/t. The suitable amount of lime was 1000-1500g/t. Figure 2 lime test results 2, float copper collector type and dosage test Flash float copper, the choice of copper mineral collector is very important. In this experiment, the selectivity of copper collectors such as xanthate, Z-200, ethylsulfide, SP, xanthate/butylammonium black drug was investigated, and the screening test of collector was carried out. The test results are shown in Table 5, and the test flow is shown in Figure 1. The results show that SP has better flotation effect and its copper grade and recovery rate are higher. As the amount of use increases, the copper recovery rate increases, but the grade also decreases. A suitable amount of collector is about 10 g/t. The results of the SP collector dosage test are shown in Figure 3. Table 5 Copper collector selection test results Collection and dosage of collector / (g·t -1 ) product name Yield Copper grade Copper recovery Butyl xanthate 20 Copper concentrate 4.38 11.66 84.24 Tailings 95.62 0.1 15.76 Raw ore 100.0 0.607 100.0 Z-200 30 Copper concentrate 7.43 6.84 85.92 Tailings 92.57 0.09 14.08 Raw ore 100.0 0.592 100.0 Ammonia acetate 20 Copper concentrate 3.93 12.22 80.01 Tailings 96.01 0.125 19.99 Raw ore 100.0 0.6 100.0 SP 10 Copper concentrate 2.44 22.24 84.5 Tailings 97.56 0.105 15.5 Raw ore 100.0 0.598 100.0 Butyl xanthate: butylammonium black drug 20:5 Copper concentrate 6.87 7.54 89.69 Tailings 93.13 0.064 10.31 Raw ore 100.0 0.58 100.0 Figure 3 Collector SP dosage test results 3. Test of copper-sulfur mixed flotation collector The copper-sulfur mixed float is carried out in a weakly alkaline medium. The butyl xanthate has a strong ability to capture pyrite in a weakly alkaline medium. As a collector of copper-sulfur minerals, a mixed collector is considered. Test conditions: the tailings after the flash float copper is used as the ore supply, in order to suppress the entrainment of the gangue minerals, an appropriate amount of water glass is added before the collector, and the conditions of the mixed collectors in different proportions are tested. The test results of copper and sulfur mixed float collectors are shown in Table 6. The test results show that the butyl xanthate is mixed with the butyl ammonium black drug, and the suitable ratio is butylammonium black drug: butyl xanthate = 1:2. The suitable dosage of the combined collector is butylammonium black and butylxanthate, respectively, 15 and 30 g/t. Table 6 Test results of copper-sulfur mixed float collector Collector dosage / (g·t -1 ) product name Yield Copper grade Copper work recovery rate Butyl ammonium black medicine 10 Coarse concentrate 5.50 1.98 72.73 Tailings 94.50 0.48 27.27 Feed mine 100.0 0.166 100.0 Butyl ammonium black medicine 20 Coarse concentrate 6.86 1.79 74.53 Tailings 93.24 0.045 25.47 Feed mine 100.0 0.165 100.0 Butyl ammonium black drug: butyl xanthate 7.5:15 Coarse concentrate 10.41 1.29 82.29 Tailings 90.34 0.032 17.71 Feed mine 100.0 0.163 100.0 Butyl ammonium black drug: butyl xanthine 10:20 Coarse concentrate 9.58 1.65 85.77 Tailings 90.42 0.029 14.23 Feed mine 100.0 0.18 100.0 Butyl ammonium black drug: butyl xanthate 10:5 Coarse concentrate 10.12 1.33 78.10 Tailings 90.88 0.042 11.90 Feed mine 100.0 0.17 100.0 Butyl ammonium black drug: butyl xanthate 15:7.5 Coarse concentrate 13.08 1.10 82.54 Tailings 86.92 0.035 17.46 Feed mine 100.0 0.17 100.0 Butyl ammonium black drug: butyl xanthate 10:10 Coarse concentrate 11.50 1.18 76.92 Tailings 90.34 0.046 8.76 Feed mine 100.00 0.18 100.0 Butyl ammonium black drug: butyl xanthine 15:15 Coarse concentrate 13.56 1.05 80.46 Tailings 86.44 0.04 19.54 Feed mine 100.0 0.18 100.0 4, copper and sulfur separation test Lime is an effective and inexpensive inhibitor in the separation of copper and sulfur. Due to the close relationship between some copper minerals and pyrite, it is difficult to dissociate the monomers under rough grinding conditions, and the metal minerals must be further dissociated by re-grinding to create conditions for the separation of copper and sulfur. At the same time, re-grinding can also remove the residual agent adsorbed on the mineral surface, and the fresh mineral surface appears, which is beneficial to the full inhibition of pyrite by CaO, thereby improving the separation effect of copper and sulfur. Test conditions: The copper-sulfur mixed concentrate was used as the ore, and the conditions of re-grinding and no-grinding, and adding different inhibitors were tested. The results of copper and sulfur separation test are shown in Table 7. The test results show that the regrind of the mixed concentrate and the addition of lime-based inhibitors, the grade and recovery rate of the copper concentrate are significantly improved, and the recovery rate of the sulfur concentrate is also improved. It can be seen that re-grinding can significantly improve the separation effect of copper and sulfur. From the results in Table 7, it can be seen that the addition of lime 800g / t and sodium sulfite 200g / t in the mill after the separation index of copper and sulfur is slightly better, comprehensive consideration, the choice of copper and sulfur separation operating conditions for regrind fineness -74μm95%, while in the mill Add lime l000g/t. Table 7 Copper and sulfur separation test results Test conditions product name Copper grade Sulfur grade Copper work recovery rate Sulfur recovery rate blank Copper concentrate 1.56 39.65 85.09 86.83 Sulfur concentrate 0.58 12.76 14.91 13.17 Lime 800g/t Copper concentrate 7.32 34.19 69.76 13.28 Sulfur concentrate 0.42 29.56 30.24 86.72 Regrind fineness -74μm 95% lime 1000g/t (add mill) Copper concentrate 10.91 38.06 75.92 11.09 Sulfur concentrate 0.33 29.1 24.08 88.91 Regrind fineness -74μm95%, lime 800+ bleaching powder 200g/t (add mill) Copper concentrate 8.54 29.44 76.85 9.53 Sulfur concentrate 0.31 28.72 23.15 90.47 Copper concentrate 11.29 36.36 76.36 10.26 Regrind fineness -74μm95%, lime 800+ sodium sulfite 200g/t (add mill) Sulfur concentrate 0.3 27.31 23.64 89.44 Table 8 Small closed circuit test results product name Yield grade Recovery rate Cu Au, g/t S Cu Au S Copper concentrate 1.82 31.17 4.7 27.59 93.53 52.17 7.89 Sulfur concentrate 6.53 0.32 0.78 43.2 3.44 31.06 44.31 Tailings 91.65 0.02 0.03 3.32 3.02 16.77 47.8 Raw ore 100.0 0.6 0.17 6.36 100.0 100.0 100.0 200CC UTV,UTV 200CC,200CC Side By Side,200CC UTV For Sale TAIZHOU NEBULA POWER CO.,LTD , https://www.xingyunutv.com