A ore dressing process for recovering gold and silver from sulfide concentrate

Abstract

The present invention belongs to the field of mineral processing technology, and particularly relates to a mineral processing process for recovering gold and silver from sulfide concentrate. The method first uses a de-agent to de-agent the sulfide concentrate, and then re-grinds it after de-agenting to a specified fineness, and then adds a passivating agent or a deactivating agent to passivate the surface of non-gold and silver-bearing minerals, and finally adds a variety of flotation agents to perform multiple flotation operations to separate high-grade gold and silver concentrates from the sulfide concentrate. The present invention lays a foundation for the production process of directly selecting precious metals such as gold and silver from sulfide concentrate. Compared with the existing process, the technical solution provided by the present invention has the advantages of low cost, simple operation, high efficiency in extracting gold and silver, and no environmental pressure. It not only effectively solves the problem of difficult recovery of precious metals associated with complex sulfide concentrates, but also reduces the load of subsequent smelting operations, achieving the purpose of both environmental and economic benefits.

Description

Technical Field

[0001] The invention belongs to the technical field of ore dressing, and in particular relates to an ore dressing process for recovering gold and silver from sulfide concentrate. Background Art

[0002] Sulfide lead-zinc ore (including pyrite) is a common gold- and silver-bearing mineral with a wide distribution and large reserves in my country. At present, the flotation process is generally used for lead-zinc sulfide ore. In the flotation of lead-zinc ore, most of the silver and gold are mainly enriched in lead concentrate and sulfur concentrate, and a small part of the gold and silver are enriched in zinc concentrate. Unfortunately, however, the current non-ferrous metal market does not price the gold associated with zinc concentrate and the silver associated with sulfur concentrate. The silver associated with zinc concentrate is generally calculated at 5-10% of the market price, and the gold associated with sulfur concentrate is generally calculated at 55% of the market price. Compared with the gold and silver in lead concentrate, which are priced at more than 80% of the market price, the pricing coefficient of gold and silver in zinc concentrate and sulfur concentrate is very low. Due to the low pricing coefficient of gold and silver in the sales process of zinc concentrate and sulfur concentrate, the beneficiation plant failed to obtain the benefits it deserved, causing certain economic losses to the enterprise. Therefore, how to further separate and recover gold and silver in sulfide concentrate is of great significance for improving the comprehensive utilization rate of resources and increasing the economic benefits of enterprises.

[0003] At present, there are few methods for directly recovering gold and silver from zinc concentrate. In industry, gold and silver are mainly recovered from waste slag after zinc smelting. Generally, wet leaching is adopted, and an aqueous solution of alkali metal cyanide (such as potassium cyanide, sodium cyanide, etc.) is used as a solvent to leach gold and silver from zinc smelting slag, and then extract gold and silver from the leaching solution containing gold and silver. As we all know, cyanide is a highly toxic substance and although this recovery method can effectively recover the associated gold and silver in zinc concentrate, the recovery rate of gold and silver is not high, and the waste of gold and silver resources is serious. Especially in the previous zinc smelting, the loss rate of silver alone is more than 10%. The pyrometallurgical process is a smelting method that utilizes the different boiling points of gold and silver and other impurity metals to recover them through multiple processes in a high-temperature reducing atmosphere. However, this process has high energy consumption and serious environmental pollution, and is currently rarely used in industry.

[0004] As for the recovery of associated gold in sulfur (pyrite) concentrate, it depends on the main form of gold. If the associated gold in the sulfur concentrate mainly exists in the form of free natural gold and free gold minerals, the leaching method can achieve a better recovery effect. However, there is less gold in the form of free natural gold and free gold minerals in nature, and most of the gold is wrapped or impregnated in pyrite in the form of fine or submicronized particles. For this part of gold in the form of microscopic gold and wrapped gold, if the conventional cyanide leaching method is directly used for extraction, not only the leaching rate is low and the leaching effect is not ideal, but it will also increase production costs, generate more toxic waste acid and waste gas, and increase environmental pressure.

[0005] It can be seen that the best way to reduce the loss of gold and silver in the smelting process is to separate the sulfide concentrate as much as possible before it enters the smelting process. To this end, it is necessary to develop a set of economic, environmentally friendly, simple to operate, and low-cost separation processes for precious metals such as gold and silver at the front end of smelting, so as to separate the gold and silver in the sulfide concentrate as much as possible at the front end of smelting, improve the grade of the ore entering the smelting, reduce the physical packaging of precious metal minerals, and increase the dissociation of minerals, thereby improving the leaching efficiency, reducing the loss of gold and silver in the subsequent smelting process, and improving the comprehensive utilization rate of resources.

[0006] Based on the existing problems in the recovery of precious metals such as gold and silver in sulfide ores, especially after flotation, the present invention has developed an economical, environmentally friendly, green, efficient and easy-to-operate comprehensive gold and silver extraction process, which is of great significance to the sustainable development of my country's precious metal industry. Summary of the invention

[0007] The purpose of the present invention is to provide a mineral processing technology for recovering gold and silver from sulfide concentrate in order to solve the problems of low separation efficiency, low gold and silver grade and high resource recovery production cost in the existing technology.

[0008] The present invention adopts the following technical solutions to achieve the above purpose:

[0009] The present invention discloses a mineral processing technology for recovering gold and silver from sulfide concentrate, and the mineral processing technology specifically comprises the following steps:

[0010] S1. De-doping: firstly, the sulfide concentrate is mixed with water, the slurry concentration is adjusted to between 60% and 70%, a certain amount of de-doping agent is added after mixing evenly, and the de-doping is fully stirred; the sulfide concentrate contains gold and / or silver;

[0011] S2. Grinding: The slurry obtained in S1 is transferred to the grinding equipment and ground to a specified fineness;

[0012] S3. Passivation or deactivation: The slurry obtained in S2 is transferred to a stirring device, water is added to adjust the slurry concentration to 10-45%, and then a passivating agent or a deactivating agent is added, and the mixture is stirred thoroughly to completely passivate and deactivate the surface of the dissociated mineral;

[0013] S4. Flotation: The slurry obtained in S3 is transferred to the flotation machine, and dispersants, inhibitors, and collectors are added in sequence to float precious metals such as gold and silver.

[0014] Preferably, the present invention provides a beneficiation process for recovering gold and silver from sulfide concentrate, wherein the sulfide concentrate may come from the flotation of ore or from the flotation of solid waste and / or smelting slag, and is more preferably from the flotation of ore.

[0015] Preferably, the present invention provides a beneficiation process for recovering gold and silver from a sulfide concentrate. The beneficiation process can be used to recover gold and / or silver from a sulfide concentrate. The sulfide concentrate is selected from at least one of a zinc concentrate and a sulfur concentrate; the sulfur concentrate refers to a pyrite concentrate product having a sulfur grade of more than 35% and / or an iron grade of more than 30; the zinc concentrate refers to a sphalerite concentrate product having a zinc grade of more than 20%.

[0016] Preferably, in a mineral processing process for recovering gold and silver from sulfide concentrate of the present invention, in S1, the de-agent comprises at least one of sodium sulfide, sodium hydrosulfide, oxalic acid and activated carbon, more preferably sodium sulfide, and the amount used is between 3 and 50 kg / t.

[0017] Preferably, in the mineral processing process for recovering gold and silver from sulfide concentrate of the present invention, in S1, the slurry concentration is between 60% and 70%, and more preferably between 66% and 68%.

[0018] Preferably, in a beneficiation process for recovering gold and silver from sulfide concentrate of the present invention, when the processing object is sulfide concentrate, in S2, the grinding fineness is -0.038 mm accounting for more than 80%.

[0019] Preferably, in the ore dressing process for recovering gold and silver from sulfide concentrate of the present invention, when the processing object is zinc concentrate, in S2, the grinding fineness is -0.023 mm accounting for more than 80%.

[0020] Preferably, in the mineral processing process for recovering gold and silver from sulfide concentrate of the present invention, when the sulfide concentrate is sulfur concentrate, in S3, the passivating agent comprises at least one of calcium hypochlorite, hypochlorous acid, sodium hypochlorite, potassium permanganate and hydrogen peroxide, more preferably calcium hypochlorite, and the amount used is between 100 and 3000 g / t.

[0021] Preferably, in a beneficiation process for recovering gold and silver from a sulfide concentrate of the present invention, when the sulfide concentrate is a zinc concentrate, in S3, the deactivator comprises at least one of sodium cyanide, sodium sulfide, sodium hydrosulfide, potassium iodide and lime, more preferably sodium sulfide, and the amount used is between 3 and 50 kg / t.

[0022] Preferably, in the mineral processing process for recovering gold and silver from sulfide concentrate of the present invention, in S3, the slurry concentration is between 10 and 45%, and more preferably between 30 and 35%.

[0023] Preferably, in a beneficiation process for recovering gold and silver from a sulfide concentrate of the present invention, in S4, the dispersant includes at least one of water glass, salified water glass, acidified water glass, sodium hexametaphosphate, and sodium fluorosilicate, more preferably water glass, and the amount used is between 0 and 500 g / t.

[0024] Preferably, in the mineral processing process for recovering gold and silver from sulfide concentrate of the present invention, when the sulfide concentrate is a sulfur concentrate, in S4, the inhibitor includes at least one of sodium cyanide, calcium oxide, dextrin, starch, and sodium humate, and is further preferably calcium oxide, and the dosage is between 100 and 3000 g / t.

[0025] Preferably, in a beneficiation process for recovering gold and silver from a sulfide concentrate of the present invention, when the sulfide concentrate is a zinc concentrate, in S4, the inhibitor includes at least one of zinc sulfate, sodium sulfite, sodium bisulfite, and formaldehyde, and is further preferably zinc sulfate, with an amount of 100 to 3000 g / t.

[0026] Preferably, in a beneficiation process for recovering gold and silver from a sulfide concentrate of the present invention, in S4, the collector is at least one of the organic substances having structures of formula (1) to (4), preferably an organic substance having structures of formula (2) and / or (3); wherein the collector having structures of formula (2) and / or (3) is prepared by the following process:

[0027] According to weight, 10-30 parts of alcohol organic matter, 1-10 parts of phosphorus trichloride, 10-100 parts of organic solvent, 1-20 parts of elemental sulfur, 1-20 parts of triethylamine, 3-10 parts of strong acid or strong base are prepared; alcohol organic matter, phosphorus trichloride, organic solvent, elemental sulfur, triethylamine, strong acid or strong base are prepared; firstly, the prepared alcohol organic matter, phosphorus trichloride and organic solvent are uniformly mixed to obtain a mixed solution A;

[0028] Add the prepared elemental sulfur and triethylamine into the mixed solution A, and then stir and mix thoroughly;

[0029] Then, 3-10 parts of a prepared strong acid or a strong base are added, preferably 9-10 parts of a strong base are added.

[0030] Preferably, in a beneficiation process for recovering gold and silver from a sulfide concentrate of the present invention, in preparing a collector having a structure of formula (2) and / or formula (3), the organic solvent is at least one of pyrimidine, dichloromethane, and ether; the strong acid is hydrochloric acid; the strong base is at least one of ammonia water, sodium hydroxide, and potassium hydroxide; and the alcohol organic matter is at least one of ethanol, n-propanol, isopropanol, n-butanol, and isobutanol.

[0031] As a further preference, when preparing the collector of the structure of formula (2) and / or formula (3), elemental sulfur and triethylamine are configured in a mass ratio of 1:1.

[0032] Preferably, in the mineral processing process for recovering gold and silver from sulfide concentrate of the present invention, in S4, the amount of the collector is between 10 and 500 g / t.

[0033]

[0034]

[0035] Preferably, in the present invention, a beneficiation process for recovering gold and silver from sulfur concentrate and a method for using the same, in S4, the flotation operation comprises at least one roughing operation, at least one fine selection operation, and at least one scavenging operation.

[0036] In industrial applications, the amount of collector used is 100-200 g / t, preferably 125-175 g / t, for rough selection of gold and silver; and 30-40 g / t for sweep selection.

[0037] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0038] ① The present invention breaks the traditional smelting and sorting technology ideas, and innovatively uses grinding, drug removal, deactivation (passivation), and flotation to separate and recover gold and silver in sulfide concentrate. These innovative combinations effectively solve the problem of gold and silver associated with sulfide concentrate and gold and silver associated with zinc concentrate, not only further strengthening the recovery of gold and silver, but also improving the product quality of sulfide concentrate.

[0039] ② The present invention has a simple production process and high sorting efficiency. It can not only produce some qualified gold and silver concentrates, but also reduce the load of subsequent smelting operations, optimize the smelting conditions of subsequent concentrates, increase the economic benefits of the enterprise while reducing production costs, and realize efficient and comprehensive recovery of valuable metals.

[0040] ③ The present invention lays a foundation for the production process of directly selecting precious metals from sulfur concentrate. Compared with conventional smelting methods, the technical solution provided by the present invention has the advantages of low cost, simple operation, high efficiency in extracting gold and silver, and no environmental pressure, and can achieve the unity of environmental and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Attached Figure 1 This is the ore dressing flow chart used in Example 1;

[0042] Attached Figure 2 This is the mineral processing flow chart used in Example 2. DETAILED DESCRIPTION

[0043] The following examples are intended to further illustrate the content of the present invention, but are not intended to limit the protection scope of the claims of the present invention.

[0044] (1) Ore raw materials

[0045] The ore raw materials were taken from a lead-zinc mine in Hengyang, Hunan. After conventional flotation, sulfur concentrate and zinc concentrate were obtained; among them, the sulfur concentrate contained 42% sulfur, 2.0g / t gold, and 40g / t silver; the results of phase analysis showed that the main sulfur-containing mineral in the sulfur concentrate was pyrite, the main gold-containing mineral was native gold, and the main silver-containing mineral was native silver. The zinc concentrate contained 48% zinc, 1.5g / t gold, and 100g / t silver; the results of phase analysis showed that the main zinc-containing mineral in the zinc concentrate was sphalerite, the main gold-containing mineral was native gold, and the main silver-containing mineral was native silver.

[0046] When gold and silver are collected by flotation of sulfur concentrate, the de-agent used is sodium sulfide, the passivating agent is calcium hypochlorite, the gold and silver collecting agent is implementation agent 1 or implementation agent 2, the dispersant is water glass, and the inhibitor is lime.

[0047] When zinc concentrate is flotated to capture gold and silver, the de-agent used is oxalic acid, the deactivator is sodium sulfide, the gold and silver collector is implementation reagent 1 or implementation reagent 2, the dispersant is water glass, and the inhibitor is zinc sulfate.

[0048] (2) Preparation of gold and silver collectors

[0049] In a container equipped with a stirrer, 30 parts of isobutanol, 10 parts of phosphorus trichloride and 100 parts of dichloromethane were added, and after sufficient stirring until complete reaction (reaction time was 2 hours), 11 parts of elemental sulfur were added at one time, and 11 parts of triethylamine were added dropwise. After sufficient stirring for 8 hours until complete reaction, 10 parts of sodium hydroxide were added, and the solution was stirred until it became a brown liquid to obtain the collector, which was recorded as implementation reagent 1.

[0050] In a container equipped with a stirrer, 15 parts of isobutanol, 5 parts of phosphorus trichloride and 50 parts of dichloromethane were added, and after sufficient stirring until complete reaction (reaction time was 1 hour), 6 parts of elemental sulfur were added at one time, and 6 parts of triethylamine were added dropwise. After further sufficient stirring for 6 hours until complete reaction, 6 parts of sodium hydroxide were added, and the mixture was stirred until the solution became a yellow-brown liquid to obtain the collector, which was recorded as implementation reagent 2.

[0051] Example 1-1

[0052] Take 1000g of dry sulfur concentrate obtained by flotation (particle size of -0.074mm accounts for more than 80%), put it into a stirring tank, add water to adjust the pulp concentration to 66%, then add 30kg / t of sodium sulfide, stir for half an hour and transfer it to a ball mill, grind it to -0.038mm accounts for more than 80%, take it out, add 300g / t of calcium hypochlorite and adjust the pulp concentration to 30%, stir for half an hour and transfer it to a flotation machine, then add 80g / t of water glass, 150g / t of lime, and 150g / t of implementation reagent 1, stir each reagent for 3 minutes, and then start the roughing operation, the roughing time is 3 minutes, the obtained roughing concentrate is subjected to two blank selections to obtain the final concentrate; the obtained roughing tailings are subjected to two scavengings to obtain the final tailings, and 30g / t of implementation reagent 1 is added each time; the middlings of each selection operation and the concentrate of the scavenging operation are returned to the previous operation in turn. The obtained results are recorded as Example 1-1. The experimental results are shown in Table 1, and the experimental process is shown in Figure 1 .

[0053] Example 1-2

[0054] The other conditions were consistent with those of Example 1-1, except that the gold and silver collector used was implementation reagent 2; the results obtained were recorded as Example 1-2.

[0055] Comparative Example 1-1

[0056] The other conditions are consistent with those of Example 1-1, except that no de-drug operation is performed, that is, no sodium sulfide is added; the results obtained are recorded as Comparative Example 1-1.

[0057] Comparative Example 1-2

[0058] The other conditions are consistent with those of Example 1-1, except that the grinding fineness is -0.038 mm, accounting for 50%. The results obtained are recorded as Comparative Example 1-2.

[0059] Comparative Examples 1-3

[0060] The other conditions are consistent with those of Example 1-1, except that there is no grinding operation, and the results obtained are recorded as Comparative Example 1-3.

[0061] Comparative Examples 1-4

[0062] The other conditions are consistent with those of Example 1-1, except that no passivation operation is performed, that is, no calcium hypochlorite is added; the results obtained are recorded as Comparative Example 1-4.

[0063] Comparative Examples 1-5

[0064] The other conditions are consistent with those of Example 1-1, except that the gold and silver collector used is xanthate; the results obtained are recorded as Comparative Example 1-5.

[0065] Comparative Examples 1-6

[0066] The other conditions are consistent with those of Example 1-1, except that the gold and silver collector used is mercaptobenzothiazole; the results obtained are recorded as Comparative Example 1-6.

[0067] Example 2-1

[0068] Take 1000g of zinc concentrate dry ore obtained by flotation (particle size of -0.074mm accounts for more than 82%), put it into a stirring tank, add water to adjust the pulp concentration to 68%, then add 3kg / t of oxalic acid, stir for half an hour and transfer it to a ball mill, grind it to -0.023mm accounts for more than 80%, take it out, add 1000g / t of sodium sulfide and adjust the pulp concentration to 35%, stir for half an hour and transfer it to a flotation machine, then add 100g / t of water glass, 800g / t of zinc sulfate, and 150g / t of implementation reagent 1, stir each reagent for 3 minutes, and then start the roughing operation, the roughing time is 3 minutes, the obtained roughing concentrate is subjected to two blank selections to obtain the final concentrate; the obtained roughing tailings are subjected to two scavengings to obtain the final tailings, and 35g / t of implementation reagent 1 is added each time; the middlings of each selection operation and the concentrates of the scavenging operation are returned to the previous operation in turn. The results are recorded as Example 2-1. The experimental results are shown in Table 2, and the experimental process is shown in Figure 2 .

[0069] Example 2-2

[0070] The other conditions are consistent with those of Example 2-1, except that the gold and silver collector used is implementation reagent 2; the results obtained are recorded as Example 2-1.

[0071] Comparative Example 2-1

[0072] The other conditions were consistent with those of Example 2-1, except that no drug removal operation was performed, that is, no oxalic acid was added; the results obtained were recorded as Comparative Example 2-1.

[0073] Comparative Example 2-2

[0074] The other conditions are consistent with those of Example 2-1, except that the grinding fineness is -0.028 mm, accounting for 50%. The results obtained are recorded as Comparative Example 2-2.

[0075] Comparative Examples 2-3

[0076] The other conditions are consistent with those of Example 2-1, except that there is no grinding operation, and the results obtained are recorded as Comparative Example 2-3.

[0077] Comparative Examples 2-4

[0078] The other conditions are consistent with those of Example 2-1, except that no inactivation operation is performed, that is, sodium sulfide is not added; the results obtained are recorded as Comparative Example 2-4.

[0079] Comparative Examples 2-5

[0080] The other conditions are consistent with those of Example 2-1, except that the gold and silver collector used is xanthate; the results obtained are recorded as Comparative Example 2-5.

[0081] Comparative Examples 2-6

[0082] The other conditions are consistent with those of Example 2-1, except that the gold and silver collector used is mercaptobenzothiazole; the results obtained are recorded as Comparative Example 2-6.

[0083] Table 1 Experimental results of the embodiment and comparative example of recovering gold and silver from sulfur concentrate

[0084]

[0085] Table 2 Experimental results of the embodiment and comparative example of recovering gold and silver from zinc concentrate

[0086]

[0087]

[0088] It can be seen from the experimental results obtained in Example 1 and Comparative Examples 1-1 to 1-6, and Example 2 and Comparative Examples 2-1 to 2-6 that the technical solution disclosed in the present invention has a good separation effect on precious metals such as gold and silver. By applying the technical solution disclosed in the present invention, a gold grade of 19.46g / t, a gold recovery rate of 84.07%; a silver grade of 411g / t, a silver recovery rate of 88.64%; and a gold-silver concentrate with a sulfur loss rate of 2.97% can be obtained from sulfur concentrate; a gold grade of 13.58g / t, a gold recovery rate of 84.79%; a silver grade of 951g / t, a silver recovery rate of 88.25%; and a gold-silver concentrate with a zinc loss rate of 1.64% can be obtained from zinc concentrate. Compared with the traditional leaching process and the conventional beneficiation process, the technical solution disclosed in the present invention not only further strengthens the recovery of gold and silver, produces high-grade gold and silver concentrates, but also reduces the load of subsequent smelting operations, reduces production costs while increasing the economic benefits of enterprises, and can achieve efficient and comprehensive recovery of associated precious metals. At the same time, it can be seen from the experimental results of Comparative Examples 1-1 to 1-6 and Comparative Examples 2-1 to 2-6 that the separation process not within the scope of protection of the present invention cannot achieve good separation of precious metals such as gold and silver. At the same time, it can be seen from Example 1 and Example 1 that the preferred collector of the present invention is very beneficial to the recovery of precious metals such as gold and silver, and has a more superior collection effect than conventional collectors.

Claims

1. A mineral processing process for recovering gold and silver from sulfide concentrate, the mineral processing process comprising the following steps: S1. De-doping: firstly mix the sulfide concentrate with water, adjust the slurry concentration between 60 and 70%, add a certain amount of de-doping agent after mixing evenly, and stir thoroughly to de-dope; the sulfide concentrate contains gold and / or silver; S2. Grinding: The slurry obtained in S1 is transferred to a grinding device and ground to a specified fineness; S3. Passivation or deactivation: Transfer the slurry obtained in S2 to a stirring device, add water to adjust the slurry concentration to 10-45%, then add a passivating agent or deactivating agent, stir thoroughly, and completely passivate and deactivate the surface of the dissociated mineral; S4. Flotation: The slurry obtained in S3 is transferred to a flotation machine, and a dispersant, an inhibitor, and a collector are added in sequence to float gold and silver; in S4, the collector is an organic matter having a structure of formula (2) and / or formula (3); In S4, the amount of the collector is between 10 and 500 g / t; Formula (2) Formula (3) Wherein, the collector of formula (2) and / or formula (3) is prepared by the following process: According to weight, 10-30 parts of alcohol organic matter, 1-10 parts of phosphorus trichloride, 10-100 parts of organic solvent, 1-20 parts of elemental sulfur, 1-20 parts of triethylamine, and 3-10 parts of strong acid or strong base are prepared; first, the prepared alcohol organic matter, phosphorus trichloride, and organic solvent are uniformly mixed to obtain a mixed solution A; Add the prepared elemental sulfur and triethylamine into the mixed solution A, and then stir and mix thoroughly; Then add 3-10 parts of the prepared strong acid or strong base.

2. A beneficiation process for recovering gold and silver from sulfide concentrate according to claim 1, characterized in that: The mineral processing process is used to recover gold and / or silver from sulfide concentrate, the sulfide concentrate is selected from at least one of zinc concentrate and sulphur concentrate, the sulphur concentrate refers to a pyrite concentrate product with a sulphur grade of more than 35% and / or an iron grade of more than 30%; the zinc concentrate refers to a sphalerite concentrate product with a zinc grade of more than 20%.

3. A beneficiation process for recovering gold and silver from sulfide concentrate according to claim 1, characterized in that: In S1, the de-agent comprises at least one of sodium sulfide, sodium hydrosulfide, oxalic acid and activated carbon, and the dosage is between 3 and 50 kg / t.

4. The ore dressing process for recovering gold and silver from sulfide concentrate according to claim 1, characterized in that: When the processing object is sulfur concentrate, in S2, the grinding fineness is -0.038 mm, accounting for more than 80%; When the processing object is zinc concentrate, in S2, the grinding fineness is -0.023 mm, accounting for more than 80%.

5. The ore dressing process for recovering gold and silver from sulfide concentrate according to claim 1, characterized in that: In S1, the slurry concentration is between 60% and 70%; In S3, the slurry concentration is between 10% and 45%.

6. A beneficiation process for recovering gold and silver from sulfide concentrate according to claim 1, characterized in that: When the sulfide concentrate is a sulfur concentrate, in S3, the passivating agent comprises at least one of calcium hypochlorite, hypochlorous acid, sodium hypochlorite, potassium permanganate, and hydrogen peroxide; the amount used is between 100 and 3000 g / t; When the sulfide concentrate is zinc concentrate, in S3, the deactivator comprises at least one of sodium cyanide, sodium sulfide, sodium hydrosulfide, potassium iodide and lime, and the amount used is between 3 and 50 kg / t.

7. A beneficiation process for recovering gold and silver from sulfide concentrate according to claim 1, characterized in that: In S4, the dispersant includes at least one of water glass, salted water glass, acidified water glass, sodium hexametaphosphate, and sodium fluorosilicate, and the amount used is between 0 and 500 g / t.

8. The ore dressing process for recovering gold and silver from sulfide concentrate according to claim 1, characterized in that: When the sulfide concentrate is a sulfur concentrate, in S4, the inhibitor includes at least one of sodium cyanide, calcium oxide, dextrin, starch, and sodium humate, and the amount used is between 100 and 3000 g / t; When the sulfide concentrate is a zinc concentrate, in S4, the inhibitor includes at least one of zinc sulfate, sodium sulfite, sodium bisulfite, and formaldehyde, and the dosage is between 100 and 3000 g / t.

9. A beneficiation process for recovering gold and silver from sulfide concentrate according to claim 1, characterized in that: In S4, the flotation operation includes at least one roughing operation, at least one cleaning operation, and at least one scavenging operation.

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