A gold-silver mineral collector and beneficiation method

Abstract

The present application belongs to the technical field of gold and silver mineral dressing, and particularly relates to a gold and silver mineral collecting agent and a dressing method. The gold and silver mineral collecting agent according to the present application comprises, by mass percentage, 10-30% of a xanthate collecting agent, 10-30% of 2-mercaptobenzimidazole, 20-40% of dialkyldithiophosphinate, 20-40% of polyethylene glycol, and has a remarkable effect on the flotation of fine gold and silver minerals. The dressing method according to the present application comprises two-stage grinding and two-stage flotation, and the gold and silver mineral collecting agent is used in the second flotation, so that normal flotation can be realized for the coarse particle size, and regrinding-strengthened flotation can be realized for the fine particle size, thereby improving the comprehensive metal recovery rate of gold and silver.

Description

Technical Field

[0001] This invention belongs to the field of gold and silver mineral beneficiation technology, specifically relating to a gold and silver mineral collector and beneficiation method. Background Technology

[0002] In gold and silver ore, the distribution rate of gold and silver in fine-grained ore (below 0.054 mm) exceeds 35%, indicating a very high content. However, during ore beneficiation, this portion of gold and silver is easily lost in the tailings, resulting in a significant waste of valuable metals. Therefore, the efficient recovery of fine-grained gold and silver minerals is a crucial issue facing ore beneficiation plants.

[0003] Existing patent literature discloses a gold ore beneficiation method employing a coarse-grained Nelson gravity separation followed by fine-grained flotation process. This method achieves the early recovery of coarse-grained visible gold minerals that are liberated first during grinding and classification. However, the gold loss rate in the tailings obtained using this method is relatively high, and the grinding cost is also high throughout the process. Existing patent literature also discloses a gold flotation collector composed of butyl xanthate, isoamyl xanthate, and butylamine black in a weight ratio of 4–8:1–5:0.5–2. However, its improvement in gold recovery is not significant; its main advantage lies in reducing the amount of collector used. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects of high gold and silver loss rate in tailings obtained from mineral processing in the prior art, especially the unsatisfactory gold and silver recovery rate in fine-grained ore, and thus provide a gold and silver mineral collector and mineral processing method.

[0005] To this end, the present invention provides the following technical solution.

[0006] The gold and silver mineral collector provided by the present invention comprises, by mass percentage, 10% to 30% xanthate collector, 10% to 30% 2-mercaptobenzimidazole, 20% to 40% dialkyl dithiophosphite, and 20% to 40% polyethylene glycol.

[0007] The gold and silver mineral collectors provided by this invention include xanthate collectors such as ethyl xanthate, isopropyl xanthate, butyl xanthate, pentyl xanthate, isopentyl xanthate, and higher xanthates (xanthates with 4 or more carbon atoms in the hydrocarbon group); dialkyl dithiophosphite includes sodium dialkyl dithiophosphite and potassium dialkyl dithiophosphite; and the relative molecular mass of polyethylene glycol is preferably 200 to 6000.

[0008] The gold and silver mineral beneficiation method provided by the present invention includes the following steps: S1: taking raw ore and performing a first-stage grinding to obtain a first-stage slurry; S2: performing a first-stage flotation on the first-stage slurry obtained in S1 to obtain a first-stage flotation concentrate and a first-stage flotation tailings; S3: performing a second-stage grinding on the first-stage flotation tailings obtained in S2 to obtain a second-stage slurry; S4: performing a second-stage flotation on the second-stage slurry obtained in S3 to obtain a second-stage flotation concentrate and a second-stage flotation tailings; a second collector is used in the second flotation, and the second collector is the gold and silver mineral collector as described in claim 1.

[0009] Preferably, the first flotation includes a first roughing stage to obtain a first roughing concentrate and a first roughing slurry, followed by a first scavenging stage and a second scavenging stage on the first roughing slurry, and a first cleaning stage and a second cleaning stage on the first roughing concentrate.

[0010] Preferably, the second flotation includes a second roughing stage to obtain a second roughing concentrate and a second roughing slurry, followed by a third and fourth scavenging stage on the second roughing slurry, and a third and fourth cleaning stage on the second roughing concentrate.

[0011] Preferably, the first coarse selection uses an activator, a first collector, and a foaming agent.

[0012] Preferably, the second coarse selection uses an activator and a second collector.

[0013] Preferably, in the first coarse selection, the dosage of activator is 100-400 g / t, the dosage of first collector is 50-100 g / t, and the dosage of foaming agent is 20-60 g / t.

[0014] Preferably, the amount of activator used in the second roughing stage is 50-200 g / t, and the amount of the second collector is 20-60 g / t.

[0015] Preferably, a first collector and a foaming agent are used in the first and second stages of scanning.

[0016] Preferably, a second collector is used in the third and fourth stages of scanning.

[0017] Preferably, in the first stage of scanning, the dosage of the first collector is 20-60 g / t, and the dosage of the foaming agent is 10-30 g / t.

[0018] Preferably, in the second stage of scanning, the dosage of the first collector is 10-30 g / t, and the dosage of the foaming agent is 5-20 g / t.

[0019] Preferably, in the third stage of scanning, the amount of the second collector is 10-40 g / t.

[0020] Preferably, in the fourth stage of scanning, the amount of the second collector is 10-20 g / t.

[0021] Preferably, in the first stage of grinding, 50% to 70% of the particles are ground to a fineness of -0.074 mm.

[0022] Preferably, the second stage of grinding produces 80% to 90% of the particles with a fineness of -0.054 mm.

[0023] Preferably, the first collector includes at least one of butyl xanthate, pentyl xanthate, isopropyl xanthate, and butylamine black.

[0024] Preferably, the activator includes at least one of copper sulfate, ammonium sulfate, copper sulfate, and ammonium sulfate.

[0025] Preferably, the foaming agent includes at least one of polyethylene glycol, terpineol, and methyl isobutyl alcohol.

[0026] In the gold and silver mineral beneficiation method provided by this invention, the flotation concentration (percentage of solid content) is 30% to 40% when flotating tailings.

[0027] The gold and silver mineral beneficiation method provided by this invention specifically includes the following steps:

[0028] (1) Take the raw stone and grind it to a fineness of -0.074mm, accounting for 50% to 70%, to obtain the first stage of slurry;

[0029] (2) Take the first stage slurry obtained in (1), adjust the flotation concentration to 30%-40%, and carry out the first flotation: ① First, carry out the first stage roughing, add 100-400 g / t of activator, 50-100 g / t of first collector, and 20-60 g / t of frother, roughing for 4-8 min to obtain the first stage roughing concentrate and the first stage roughing slurry; ② Carry out the first stage scavenging of the first stage roughing slurry, add 20-60 g / t of first collector and 10-30 g / t of frother, scavenging for 3-6 min to obtain tailings and concentrate, and return the concentrate as middlings for the first stage roughing; ③ The tailings obtained in step ② are subjected to a second stage of scavenging, with 10-30 g / t of the first collector and 5-20 g / t of the frother added. Scavenging is carried out for 2-5 minutes to obtain tailings and concentrate. The concentrate is returned as middlings to the first stage of scavenging. The tailings here are the first flotation tailings. Step ④ The first stage of cleaning is performed on the first stage rougher concentrate, which is a blank cleaning process to obtain tailings and concentrate. The tailings are returned as middlings to the first stage rougher. Step ⑤ The second stage of cleaning is performed on the concentrate obtained in step ④, which is a blank cleaning process to obtain tailings and concentrate. The tailings are returned as middlings to the first stage of cleaning. The concentrate here is the first flotation concentrate.

[0030] (3) Take the first flotation tailings obtained in (2) and grind them in the second stage until the fineness is -0.054mm, accounting for 80% to 90%, to obtain the second stage slurry;

[0031] (4) Take the second stage slurry obtained in (3), adjust the flotation concentration to 30%-40%, and perform a second flotation: ① First, perform the second stage roughing, add 50-200 g / t of activator and 20-60 g / t of second collector, roughing for 3-6 min to obtain the second stage roughing concentrate and the second stage roughing slurry; ② Perform the third stage scavenging on the second stage roughing slurry, add 10-40 g / t of second collector, scavenging for 2-5 min to obtain tailings and concentrate, and return the concentrate as middlings for the second stage roughing; ③ Take the tailings obtained in ② The fourth stage of scavenging is carried out, with 10-20 g / t of the second collector added. Scavenging is performed for 2-5 minutes to obtain tailings and concentrate. The concentrate is returned as middlings to the third stage of scavenging. The tailings here are the tailings from the second flotation. ④ The second stage rougher concentrate is subjected to a third stage of cleaning, which is a blank cleaning, to obtain tailings and concentrate. The tailings are returned as middlings to the second stage rougher. ⑤ The concentrate obtained in ④ is subjected to a fourth stage of cleaning, which is a blank cleaning, to obtain tailings and concentrate. The tailings are returned as middlings to the third stage of cleaning. The concentrate here is the concentrate from the second flotation.

[0032] The gold and silver mineral beneficiation method provided by this invention is applicable to various types of ores, including single gold mines, gold and silver mines, and gold-bearing polymetallic mines, and can achieve ideal results.

[0033] The beneficial effects of this invention are:

[0034] The gold and silver mineral collector provided by this invention comprises, by mass percentage: 10%–30% xanthate collector, 10%–30% 2-mercaptobenzimidazole, 20%–40% dialkyl dithiophosphite, and 20%–40% polyethylene glycol. This collector is highly effective in the flotation of fine-grained gold and silver ores, reducing waste of fine-grained resources and bringing significant economic benefits by improving the recovery rate of valuable metals. Specifically, the xanthate collector exhibits good collecting performance for gold and silver-bearing minerals; 2-mercaptobenzimidazole shows good selectivity for the flotation of gold and silver ores; dialkyl dithiophosphite has good adaptability to the flotation of gold and silver-bearing ores from different types or regions; and polyethylene glycol has good water solubility and compatibility, which can improve the adsorption capacity of the mineral processing reagent for valuable minerals. The combination of these reagents can form a good synergistic effect, enhancing the effect on valuable minerals.

[0035] The gold and silver mineral beneficiation method provided by this invention includes the following steps: S1: Taking raw ore and performing a first-stage grinding to obtain a first-stage slurry; S2: Performing a first-stage flotation on the first-stage slurry obtained in S1 to obtain a first-stage flotation concentrate and a first-stage flotation tailings; S3: Performing a second-stage grinding on the first-stage flotation tailings obtained in S2 to obtain a second-stage slurry; S4: Performing a second-stage flotation on the second-stage slurry obtained in S3 to obtain a second-stage flotation concentrate and a second-stage flotation tailings; a second collector is used in the second flotation, and the second collector is the aforementioned gold and silver mineral collector. This method uses a stepwise flotation process, which can achieve normal flotation of coarser particles and regrinding-enhanced flotation of finer particles, thereby improving the overall metal recovery rate of gold and silver. The second collector used is the aforementioned gold and silver mineral collector, which, in conjunction with secondary grinding and a collector that is beneficial to the flotation of fine-grained gold and silver ores, further improves the recovery rate of valuable metals. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a flowchart of the gold and silver mineral beneficiation method of the present invention. Detailed Implementation

[0038] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0039] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0040] Experimental drugs

[0041] Amyl xanthate: purity greater than 95%;

[0042] Butyl xanthate: purity greater than 95%;

[0043] Isoamyl xanthate: purity greater than 95%;

[0044] Isopropyl xanthate: purity greater than 95%;

[0045] Butylamine black powder: purity greater than 95%.

[0046] Example 1

[0047] This embodiment provides a method for beneficiating gold and silver minerals. The raw ore used has the following characteristics: gold grade of 3.14 g / t and silver grade of 3.80 g / t; exposed gold distribution rate of 90%, sulfide-encapsulated gold distribution rate of 6.5%, and silicate-encapsulated gold distribution rate of 3.5%; pyrite is the main carrier mineral for gold, and the pyrite grain size is relatively coarse; the gold distribution rate in the fine-grained fraction (below 0.054 mm) exceeds 30%; silver mainly exists in the form of gold-silver ore and antimony-silver ore, with the antimony-silver ore occurring as fine-grained, partly micro-particles. The flowchart of the beneficiation method is shown below. Figure 1 The specific steps are as follows:

[0048] (1) Take the raw stone and grind it to the first stage until the fineness is -0.074mm, accounting for 60%, to obtain the first stage slurry;

[0049] (2) Take the first stage slurry obtained in (1), adjust the flotation concentration to 35%, and perform the first flotation: ① First, perform the first stage roughing, add 200g / t of activator, 80g / t of first collector, and 40g / t of frother, roughing for 6min to obtain the first stage roughing concentrate and the first stage roughing slurry; ② Perform the first stage scavenging on the first stage roughing slurry, add 40g / t of first collector and 20g / t of frother, scavenging for 4min to obtain tailings and concentrate, and return the concentrate as middlings for the first stage roughing; ③ Put the tailings obtained in ② into The second stage of scavenging is performed, with 20 g / t of the first collector and 10 g / t of the frother added. Scavenging is carried out for 3 minutes to obtain tailings and concentrate. The concentrate is returned as middlings for the first stage of scavenging. The tailings here are the tailings of the first flotation. ④ The first stage of cleaning is performed on the concentrate obtained from the first roughing stage, which is a blank cleaning. Tailings and concentrate are obtained. The tailings are returned as middlings for the first stage of roughing. ⑤ The concentrate obtained in ④ is performed on the second stage of cleaning, which is a blank cleaning. Tailings and concentrate are obtained. The tailings are returned as middlings for the first stage of cleaning. The concentrate here is the concentrate of the first flotation.

[0050] (3) Take the first flotation tailings obtained in (2) and grind them in the second stage until the fineness is -0.054mm, accounting for 85%, to obtain the second stage slurry;

[0051] (4) Take the second stage slurry obtained in (3), adjust the flotation concentration to 35%, and perform a second flotation: ① First, perform the second stage roughing, add 100g / t of activator and 40g / t of second collector, roughing for 4min to obtain the second stage roughing concentrate and the second stage roughing slurry; ② Perform the third stage scavenging on the second stage roughing slurry, add 30g / t of second collector, scavenging for 3min to obtain tailings and concentrate, and return the concentrate as middlings for the second stage roughing; ③ Perform the fourth stage scavenging on the tailings obtained in ②. 1. Add 15g / t of the second collector and scaveng for 3 minutes to obtain tailings and concentrate. Return the concentrate as middlings for the third stage of scavenging. The tailings here are the tailings from the second flotation. 2. Perform a third stage of cleaning on the concentrate from the second roughing stage (blank cleaning) to obtain tailings and concentrate. Return the tailings as middlings for the second roughing stage. 3. Perform a fourth stage of cleaning on the concentrate obtained in step 4 (blank cleaning) to obtain tailings and concentrate. Return the tailings as middlings for the third stage of cleaning. The concentrate here is the concentrate from the second flotation.

[0052] In this embodiment, the first collector used is pentyl xanthate; the second collector is: by mass percentage, pentyl xanthate accounts for 20%, 2-mercaptobenzimidazole accounts for 20%, sodium dialkyl dithiophosphate accounts for 30%, and polyethylene glycol 200 accounts for 30%; the activator is copper sulfate; and the foaming agent is terpineol.

[0053] Example 2

[0054] This embodiment provides a method for beneficiating gold and silver minerals. The raw ore used has the following characteristics: the gold grade is 3.07 g / t, and the silver grade is 3.76 g / t; the distribution rate of exposed gold is 85%, the distribution rate of sulfide-encased gold is 10%, and the distribution rate of silicate-encased gold is 5%; pyrite is the main carrier mineral for gold, and the pyrite grain size is relatively coarse; the gold distribution rate in the fine-grained fraction (below 0.054 mm) exceeds 30%; silver mainly exists in the form of gold-silver ore and antimony-silver ore, with the antimony-silver ore occurring as fine-grained, partly micro-particles. The flowchart of the beneficiation method is shown below. Figure 1 The specific steps are as follows:

[0055] (1) Take the raw stone and grind it to the first stage until the fineness is -0.074mm, accounting for 60%, to obtain the first stage slurry;

[0056] (2) Take the first stage slurry obtained in (1), adjust the flotation concentration to 35%, and perform the first flotation: ① First, perform the first stage roughing by adding 100g / t of activator, 50g / t of the first collector, and 20g / t of frother, and rough for 4 minutes to obtain the first stage roughing concentrate and the first stage roughing slurry; ② Perform the first stage scavenging on the first stage roughing slurry by adding 20g / t of the first collector and 10g / t of frother, and scaveng for 3 minutes to obtain the tailings and concentrate. Return the concentrate as middlings for the first stage roughing; ③ Perform the tailings obtained in ② In the second stage of scavenging, 10 g / t of the first collector and 5 g / t of the frother are added, and scavenging is carried out for 2 minutes to obtain tailings and concentrate. The concentrate is returned as middlings to the first stage of scavenging. The tailings here are the tailings of the first flotation. ④ The first stage of cleaning is carried out on the concentrate obtained from the first roughing stage, which is a blank cleaning. Tailings and concentrate are obtained. The tailings are returned as middlings to the first stage of roughing. ⑤ The concentrate obtained in ④ is carried out on the second stage of cleaning, which is a blank cleaning. Tailings and concentrate are obtained. The tailings are returned as middlings to the first stage of cleaning. The concentrate here is the concentrate of the first flotation.

[0057] (3) Take the first flotation tailings obtained in (2) and grind them in the second stage until the fineness is -0.054mm, accounting for 85%, to obtain the second stage slurry;

[0058] (4) Take the second stage slurry obtained in (3), adjust the flotation concentration to 35%, and perform a second flotation: ① First, perform the second stage roughing, add 50 g / t of activator and 20 g / t of second collector, roughing for 3 min to obtain the second stage roughing concentrate and the second stage roughing slurry; ② Perform the third stage scavenging on the second stage roughing slurry, add 10 g / t of second collector, scavenging for 2 min to obtain tailings and concentrate, and return the concentrate as middlings for the second stage roughing; ③ Perform the fourth stage scavenging on the tailings obtained in ②. Add 10g / t of the second collector, scaveng for 2 minutes to obtain tailings and concentrate. Return the concentrate as middlings for the third stage of scavenging. The tailings here are the tailings from the second flotation. ④ Perform a third stage of cleaning on the concentrate from the second roughing stage, which is a blank cleaning process, to obtain tailings and concentrate. Return the tailings as middlings for the second roughing stage. ⑤ Perform a fourth stage of cleaning on the concentrate obtained in step ④, which is a blank cleaning process, to obtain tailings and concentrate. Return the tailings as middlings for the third stage of cleaning. The concentrate here is the concentrate from the second flotation.

[0059] In this embodiment, the first collector used is butyl xanthate; the second collector is, by mass percentage, 10% isopropyl xanthate, 10% 2-mercaptobenzimidazole, 40% sodium dialkyl dithiophosphate, and 40% polyethylene glycol 3000; the activator is ammonium sulfate; and the foaming agent is terpineol.

[0060] Example 3

[0061] This embodiment provides a method for beneficiating gold and silver minerals. The raw ore used has the following characteristics: the gold grade is 3.20 g / t, and the silver grade is 3.82 g / t; the distribution rate of exposed gold is 80%, the distribution rate of sulfide-encapsulated gold is 13%, and the distribution rate of silicate-encapsulated gold is 7%; pyrite is the main carrier mineral for gold, and the pyrite grain size is relatively coarse; the gold distribution rate in the fine-grained fraction (below 0.054 mm) exceeds 30%; silver mainly exists in the form of gold-silver ore and antimony-silver ore, with the antimony-silver ore occurring as fine-grained, partly micro-particles. The flowchart of the beneficiation method is shown below. Figure 1 The specific steps are as follows:

[0062] (1) Take the raw stone and grind it to the first stage until the fineness is -0.074mm, accounting for 60%, to obtain the first stage slurry;

[0063] (2) Take the first stage slurry obtained in (1), adjust the flotation concentration to 35%, and perform the first flotation: ① First, perform the first stage roughing by adding 400 g / t of activator, 100 g / t of first collector, and 60 g / t of frother, and rough for 8 minutes to obtain the first stage roughing concentrate and the first stage roughing slurry; ② Perform the first stage scavenging on the first stage roughing slurry by adding 60 g / t of first collector and 30 g / t of frother, and scaveng for 6 minutes to obtain tailings and concentrate. Return the concentrate as middlings for the first stage roughing; ③ Perform the tailings obtained in ② In the second stage of scavenging, 30 g / t of the first collector and 20 g / t of the frother are added, and scavenging is carried out for 5 minutes to obtain tailings and concentrate. The concentrate is returned as middlings for the first stage of scavenging. The tailings here are the tailings of the first flotation. ④ The first stage of cleaning is carried out on the concentrate obtained from the first stage roughing, which is a blank cleaning. Tailings and concentrate are obtained. The tailings are returned as middlings for the first stage roughing. ⑤ The concentrate obtained in ④ is carried out on the second stage of cleaning, which is a blank cleaning. Tailings and concentrate are obtained. The tailings are returned as middlings for the first stage of cleaning. The concentrate here is the concentrate of the first flotation.

[0064] (3) Take the first flotation tailings obtained in (2) and grind them in the second stage until the fineness is -0.054mm, accounting for 85%, to obtain the second stage slurry;

[0065] (4) Take the second stage slurry obtained in (3), adjust the flotation concentration to 35%, and perform a second flotation: ① First, perform the second stage roughing, add 200g / t of activator and 60g / t of second collector, roughing for 6min to obtain the second stage roughing concentrate and the second stage roughing slurry; ② Perform the third stage scavenging on the second stage roughing slurry, add 40g / t of second collector, scavenging for 5min to obtain tailings and concentrate, and return the concentrate as middlings for the second stage roughing; ③ Perform the fourth stage scavenging on the tailings obtained in ②. 1. Add 20g / t of the second collector and scaveng for 5 minutes to obtain tailings and concentrate. Return the concentrate as middlings for the third stage of scavenging. The tailings here are the tailings from the second flotation. 2. Perform a third stage of cleaning on the concentrate from the second roughing stage (blank cleaning) to obtain tailings and concentrate. Return the tailings as middlings for the second roughing stage. 3. Perform a fourth stage of cleaning on the concentrate obtained in step 4 (blank cleaning) to obtain tailings and concentrate. Return the tailings as middlings for the third stage of cleaning. The concentrate here is the concentrate from the second flotation.

[0066] In this embodiment, the first collector used is pentyl xanthate; the second collector is 30% butyl xanthate, 30% 2-mercaptobenzimidazole, 20% sodium dialkyl dithiophosphate, and 20% polyethylene glycol 6000 by mass percentage; the activator is copper sulfate and ammonium sulfate in a mass ratio of 1:1; and the foaming agent is methyl isobutyl alcohol.

[0067] Comparative Example 1

[0068] This comparative example provides a method for beneficiating gold and silver minerals. Compared with Example 1, the difference is that the second collector used is: by mass percentage, 60% butyl xanthate, 30% isopentyl xanthate, and 10% butylamine black.

[0069] Comparative Example 2

[0070] This comparative example provides a method for beneficiating gold and silver minerals. Compared with Example 1, the difference is that the second collector used is: by mass percentage, 20% butylamine black, 20% 2-mercaptobenzimidazole, 30% sodium dialkyl dithiophosphate, and 30% polyethylene glycol 200.

[0071] Comparative Example 3

[0072] This comparative example provides a method for beneficiating gold and silver minerals. Compared with Example 1, the difference is that the second collector used is: by mass percentage, 30% pentyl xanthate, 30% 2-mercaptobenzimidazole, and 40% sodium dialkyl dithiophosphate.

[0073] Comparative Example 4

[0074] This comparative example provides a method for beneficiating gold and silver minerals. Compared with Example 1, the difference is that the second collector used is: by mass percentage, 20% pentyl xanthate, 20% 2-mercaptobenzimidazole, 30% sodium phosphate, and 30% polyethylene glycol 200.

[0075] Comparative Example 5

[0076] This comparative example provides a method for beneficiating gold and silver minerals. Compared with Example 1, the difference is that the second collector used is: by mass percentage, 20% pentyl xanthate, 20% benzimidazole, 30% sodium dialkyl dithiophosphate, and 30% polyethylene glycol 200.

[0077] Comparative Example 6

[0078] This comparative example provides a method for beneficiating gold and silver minerals. Compared with Example 1, the difference is that the second collector used is: by mass percentage, 25% pentyl xanthate, 25% 2-mercaptobenzimidazole, 10% sodium dialkyl dithiophosphate, and 40% polyethylene glycol 200.

[0079] Comparative Example 7

[0080] This comparative example provides a method for beneficiating gold and silver minerals. Compared with Example 1, the difference is that steps (1) and (2) are omitted, and steps (3) and (4) are performed directly using raw stones.

[0081] Test Example 1

[0082] The grades of gold and silver in the first flotation concentrate (i.e., flotation concentrate 1), the second flotation concentrate (i.e., flotation concentrate 2), and the second flotation tailings (i.e., tailings) obtained in the examples and comparative examples were tested using GB / T7739.1-2019, and their yields and recoveries were further calculated. The results are shown in Table 1.

[0083] Table 1

[0084]

[0085]

[0086] As shown in Table 1, using the gold and silver mineral beneficiation method of this invention in conjunction with the gold and silver mineral collector provided in this invention, the gold recovery rate in the tailings is below 3%, and the silver recovery rate is below 8%. In Example 3, the gold recovery rate even reached below 2%. In contrast, in Comparative Example 1 (using an existing collector in the second flotation), Comparative Examples 2 to 5 (using a collector in the second flotation that differs from the collector provided in this invention only in a single reagent), Comparative Example 6 (using a collector in the second flotation that differs from the collector provided in this invention only in the amount of reagent), and Comparative Example 7 (directly grinding the raw ore to a fine particle size for a single flotation), the gold recovery rate in the tailings was above 8%, with most exceeding 11%, and the silver recovery rate was above 12%, reaching a maximum of 24.58%. Using the gold and silver mineral beneficiation method of this invention in conjunction with the gold and silver mineral collector provided in this invention can improve the overall metal recovery rate of gold and silver, bringing significant economic benefits.

[0087] Specifically, in the second flotation concentrate of the embodiments, the recovery rates of gold and silver were both above 22%, while in the second flotation concentrates of Comparative Examples 1 to 6, the recovery rates of gold and silver were less than 20%, with the highest being the gold recovery rate in Comparative Example 6, which was only 18.1%. The gold and silver mineral collector provided by the present invention used in the second flotation concentrate of the embodiments has a significant effect on the flotation of fine-grained gold and silver ores, reducing the waste of fine-grained resources.

[0088] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for beneficiating gold and silver minerals, characterized in that, Includes the following steps: S1: Take the raw stone and perform the first stage of grinding to obtain the first stage of ore slurry; S2: Perform the first flotation on the first slurry obtained in S1 to obtain the first flotation concentrate and the first flotation tailings; S3: The first flotation tailings obtained in S2 are subjected to a second grinding process to obtain the second slurry. S4: Perform a second flotation on the second slurry obtained in S3 to obtain a second flotation concentrate and a second flotation tailings; The first flotation process uses a first collector, which includes at least one of butyl xanthate, pentyl xanthate, isopropyl xanthate, and butylammonium black powder. The second flotation uses a second collector, which is a gold and silver mineral collector. The gold and silver mineral collector, by mass percentage, includes 10% to 30% xanthate collector, 10% to 30% 2-mercaptobenzimidazole, 20% to 40% dialkyl dithiophosphite, and 20% to 40% polyethylene glycol.

2. The gold and silver mineral beneficiation method according to claim 1, characterized in that, The first flotation includes a first roughing stage to obtain a first roughing concentrate and a first roughing slurry. The first roughing slurry is then subjected to a first scavenging stage and a second scavenging stage. The first roughing concentrate is then subjected to a first cleaning stage and a second cleaning stage.

3. The gold and silver mineral beneficiation method according to claim 2, characterized in that, The second flotation includes a second roughing stage to obtain a second roughing concentrate and a second roughing slurry. The second roughing slurry is then subjected to a third and fourth scavenging stage, and the second roughing concentrate is subjected to a third and fourth cleaning stage.

4. The gold and silver mineral beneficiation method according to claim 3, characterized in that, The first coarse selection uses an activator, a first collector, and a foaming agent; And / or, the second coarse selection uses an activator and a second collector.

5. The gold and silver mineral beneficiation method according to claim 4, characterized in that, In the first coarse selection, the dosage of activator is 100~400 g / t, the dosage of first collector is 50~100 g / t, and the dosage of foaming agent is 20~60 g / t; And / or, in the second coarse selection, the amount of activator used is 50~200 g / t, and the amount of the second collector used is 20~60 g / t.

6. The gold and silver mineral beneficiation method according to claim 3, characterized in that, The first and second stages of the sweeping process use a first collector and a foaming agent. And / or, a second collector is used in the third and fourth sweep stages.

7. The gold and silver mineral beneficiation method according to claim 6, characterized in that, In the first stage of scanning, the dosage of the first collector is 20~60 g / t, and the dosage of the foaming agent is 10~30 g / t; And / or, in the second stage of scanning, the dosage of the first collector is 10~30 g / t, and the dosage of the foaming agent is 5~20 g / t; And / or, in the third stage of scanning, the dosage of the second collector is 10~40 g / t; And / or, in the fourth stage of scanning, the amount of the second collector is 10~20 g / t.

8. The gold and silver mineral beneficiation method according to any one of claims 1 to 7, characterized in that, The first stage of grinding produces 50% to 70% of the material with a fineness of -0.074 mm. And / or, the second stage of grinding is performed until 80%~90% of the particles are ground to a fineness of -0.054mm.

9. The gold and silver mineral beneficiation method according to claim 4 or 5, characterized in that, The activator includes at least one of copper sulfate, ammonium sulfate, and copper sulfate. And / or, the foaming agent includes at least one of polyethylene glycol, terpineol, and methyl isobutyl alcohol.

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