Experimental study on symbiotic gold and silver recovery of complex polymetallic ore

Abstract:The study based on comprehensive utilization of Symbiosis gold and silver from complication polymetallic ore,under the condition with Low-pH Value, progressing comprehensive recovery to symbiosis gold and silver at the same time to ensure grade and yield not to be influenced. Gold and silver enrich to copper,lead and zinc, gold and silver 's sum total of comprehensive recovery is 80.97% and 82.00%, copper,lead, zinc, gold and silver obtain maximum comprehensive utilization.

Currently complex multi-metal sulfide ore beneficiation separation is still a problem in the field. Over the years, domestic and foreign mineral processing workers have carried out a lot of research work on the separation of polymetallic sulphide ore, and have obtained some new research results, but for some sulphide ore with complex embedded, difficult to choose, and many types of metals, now Existing mature beneficiation processes are difficult to achieve effective separation. Mainly zinc more difficult separation of copper and lead are: (1) each of useful minerals dense symbiotic, embedded in fine particle size distribution, it is necessary to make finely ground mineral achieve dissociation of monomers, but too finely pulverized produce, the flotation process Deterioration; (2) floating interlaced overlap between sulfide minerals; (3) sphalerite is easily activated by copper ions. Were associated mainly gold and silver utilization is difficult: gold, silver mineral flotation is sensitive to changes in pH of the slurry, many mineral processing for sorting the primary metallic minerals Cu, Pb, adding a large amount of lime in the flotation process. Flotation in high alkalinity pulp (pH 10~12) is not conducive to the flotation of gold and silver minerals, reducing the recovery rate of gold and silver ^"1" . This experiment studied the comprehensive recovery of gold and silver in ore without affecting the grade and yield of copper, lead and zinc without the low alkalinity of lime.

First, the nature of the original ore

Mineral composition

The ore of a mine in Anhui is lead, zinc, copper, gold and silver polymetallic sulfide ore. From the chemical analysis results in Table 1, it can be seen that the lead and zinc grades are higher and the content is about 6.35%. The copper grade is 0.36% lower; the symbiotic gold and silver are higher, 3 g/t and 31 g/t respectively.

Table 1 Results of chemical multiple analysis

Note: All gold and silver content is gram / ton

Table 2 shows the results of X-ray analysis of ore: metallic minerals galena, sphalerite; chalcopyrite copper minerals, followed tetrahedrite, small amounts of bornite; yellow iron containing mineral is iron Mine, iron ore, limonite ore. The gangue minerals are mainly calcite , followed by quartz and barite .

Process mineralogy indicates that chalcopyrite, galena, sphalerite and pyrite are mutually interdependent and complex in structure, which is not conducive to mutual dissociation. The gold and silver minerals in the ore are fine-grained, and are closely related to the symbiotic relationship between chalcopyrite, galena, sphalerite and other sulfide minerals, and gold and silver exist in the presence of inclusions, which determines the gold and silver minerals. It is difficult to completely dissociate with copper, lead, zinc and other sulfides to obtain independent products, and only integrated into chalcopyrite, galena and sphalerite concentrates for comprehensive recovery.

Table 2 Raw ore X-ray diffraction analysis results

Second, mineral processing test research

This experiment studied the comprehensive recovery of gold and silver in ore without affecting the grade and yield of copper, lead and zinc without adding lime, and designed an advanced process and developed XJD-10 and XJD-11 are two effective inhibitors, which greatly improve the recovery rate of symbiotic gold and silver, and make the recovery rate of gold and silver reach the world advanced level. The conventional separation process for solving common copper, lead and zinc complex polymetallic ores is to use lime as an inhibitor, but the gold and silver minerals are sensitive to the pH change of the slurry during flotation. In the high alkalinity pulp (pH 10-12) It is not conducive to the flotation of gold and silver minerals, and affects the recovery rate of gold and silver.

(1) Mixed coarse grinding grinding fineness test

The process flow of the mixed rough grinding grinding fineness test is shown in Figure 1, and the test results are shown in Table 3.

Fig.1 Process flow of mixed coarse grinding grinding fineness and lime dosage test

Table 3 Grinding fineness test results

From the grinding fineness test results, the content of -200 mesh from 65% to 80% has little effect on the flotation index, and the fineness of the grinding is fine, which is beneficial to the recovery of copper, zinc, gold and silver, but lead The recovery rate has dropped slightly. Considering the comprehensive consideration, the provisional grinding fineness is -200 mesh 70%.

(2) Conventional rough selection of lime

Conventional methods for treating complex polymetallic ores use lime as an inhibitor. However, copper and sulfur are closely related, which causes difficulties in separation and affects the quality of copper concentrate. In particular, the use of lime greatly reduces the recovery rate of symbiotic gold and silver. The routine roughing lime dosage test process is shown in Figure 1, and the test results are shown in Figure 2.

Figure 2 Effect of lime on the recovery rate of gold and silver

From the conventional rough lime dosage test results, it can be known that as the lime increases, the recovery rate of symbiotic gold and silver is continuously reduced.

(3) Comparison results between lime and no lime

Figure 3 Comparison test results of lime and no lime

From the comparison of lime and no lime, it can be known that the effect of lime addition on symbiotic gold and silver is very large.

(4) Experimental research on new processes

For the comprehensive utilization of symbiotic gold and silver, we first envisioned when roughing add an agent to inhibit zinc and sulfur, elected copper, lead bulk concentrate, then an agent to inhibit lead, copper and lead were separate processes ^{" 2,3,4"} . We have done a lot of experimental research. After our continuous efforts, we have successfully developed two inhibitors suitable for this process. XJD-10 is a combination of inorganic salt compounds, which can effectively achieve zinc and sulfur. The inhibition also greatly reduces the loss of symbiotic gold and silver, and solves the problem of low recovery rate of symbiotic gold and silver when suppressing sulfur; XJD-11 is a combination of inorganic salt compound and anionic natural high molecular polymer. The agent can effectively inhibit the lead in the copper-lead mixed concentrate without affecting the floatability of copper, and solves the problem that the separation of copper and lead is difficult. ^"5,6" . The advanced process flow of symbiotic gold and silver recovery of a copper-lead-zinc complex polymetallic ore in Anhui is shown in Figure 4. The test results are shown in Table 4.

Figure 4 advanced technology

Table 4 Test results

Note: The content of iron in zinc concentrate is 6%.

Third, the conclusion

According to the test results, the copper concentrate grade is 22.82%, the copper recovery rate is 72.97%; the copper concentrate contains gold grade 100.00 g/ton, the gold recovery rate is 38.46%; the copper concentrate contains silver grade 235.00 g/ton, and the silver recovery rate is 9.40. %; lead concentrate grade 45.15%, lead recovery rate 90.90%; lead concentrate containing gold grade 10.10 g / ton, gold recovery rate 24.36%; lead concentrate silver grade 234.83 g / ton, silver recovery rate 59.10%; zinc Concentrate grade 50.11%, zinc recovery rate 85.78%, zinc concentrate gold grade 12.60 g / ton, gold recovery rate 17.95% zinc concentrate silver grade 97.80 g / ton, silver recovery rate 14.50%. The total gold recovery was 80.97%, and the total silver recovery was 82.00%. Lead, zinc and copper have been effectively separated, and symbiotic gold and silver have been fully recovered. The mineral processing technical indicators have reached the international advanced level.

references

[1] Cai Ling et al., "Comprehensive Recovery of Symbiotic Gold and Silver" [M], Beijing, Metallurgical Industry Press, first edition of July 1999, 92-128, 386-426;

[2] Dong Ying, Wang Jikun, Feng Guilin, “Development and Processing of Common Nonferrous Metal Resources” [M], Beijing, Metallurgical Industry Press, August 2005, 1st edition, 66-70;

[3] Hu Xigeng, "Non-ferrous metal sulfide ore dressing" [M], Beijing, Metallurgical Industry Press, November 1987, first edition 250-271;

[4] Huang Baoguang, the flotation separation process of refractory copper sulfide and lead sulfide [J], non-ferrous metals (elite processing), 2002, (02);

[5] Yu Rihui, “Top Ten Key Technologies of Mine Separation” [M], Beijing, Mining University Press, March 2007, 1050~1064;

[6] Zhu Shuquan, “Innovative Technologies and Equipment for Mineral Processing in the Contemporary World” [M], Beijing, Metallurgical Industry Press, June 1135~1148;

The major product Fuli rice huller rubber rollers, part of grain machinery, is mainly used for rice hulling. With strong technical force, fine equipment, advanced technologies, and complete testing means, it can annually produce 500,000 various types of [Fuli" rice huller rubber rollers. Its products have been used by more than 40 domestic factories and exported to 37 countries and regions. In 2009, the factory`s sales revenue reached RMB 24,138,600, with tax turnover of RMB 2,405,000. It is a member of China Association of Agricultural Machinery Manufacturers. Fuli Rubber Roller won the National Double-excellence Gold Prize. From 2007 to 2009, it was recognized as the first place among peers by China Association of Agricultural Machinery Manufacturers (CAAMM).