A flotation method for comprehensively recovering lead, zinc, gold and silver from a sulphur concentrate

Abstract

The application discloses a flotation method for comprehensively recovering lead, zinc, gold and silver from sulphur concentrate, which comprises the following steps: 1) obtaining a pressure filtration product or a dry product of the sulphur concentrate; 2) performing grinding on the product of step 1) while adding sodium sulfide to perform combined reagent removal and pre-thickening; 3) then adding a sulfur inhibitor, after sufficient stirring, adding a collector to perform roughing to obtain roughing concentrate and roughing tailings; the collector is CY collector or / and Z-200 collector; the CY collector is a short-chain dialkyldithiophosphate or a short-chain dialkyldithiophosphoric acid, wherein the number of carbon atoms in the alkyl group is 2-3; 4) adding the sulfur inhibitor to the roughing concentrate to perform cleaning to obtain a concentrate product and cleaning tailings; 5) adding the collector to the roughing tailings to perform scavenging to obtain scavenging concentrate and final tailings. The application solves the problem of residual reagent interference in the flotation of the sulphur concentrate, and realizes efficient separation and comprehensive enrichment of lead, zinc, gold and silver minerals from the sulphur concentrate.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of mineral processing, and particularly relates to a flotation method for comprehensively recovering lead, zinc, gold and silver from a sulfur concentrate. BACKGROUND

[0002] Lead, zinc, gold and silver are widely used in the fields of mechanical industry, electrical industry, military industry, metallurgical industry, chemical industry, light industry and medical industry, and have important strategic significance for maintaining the economic development and social stability of an industry.

[0003] For lead-zinc sulfide ore, the order flotation process of 'first lead, then zinc and finally sulfur' is generally used in the mineral processing industry. After the separation of lead and zinc, the lead and zinc that are not recovered in time and the associated gold and silver are finally enriched in the sulfur concentrate. Taking a lead-zinc mineral processing plant in Hunan as an example, the gold content in the sulfur concentrate produced by the plant is averagely between 5-8 g / t, the silver content is averagely above 30 g / t, and the lead+zinc is less than or equal to 2%. According to relevant regulations, the gold content in the sulfur concentrate below 5 g / t is not priced, the gold content between 5 g / t and 15 g / t is priced with a coefficient of 0.52, and the rest of the metals are not priced, resulting in serious loss of metal mineral resources and economic loss. When the gold content in the sulfur concentrate is above 15 g / t, the sulfur concentrate can be treated as a gold concentrate, the gold pricing coefficient is increased to 0.85, and the lead, zinc and silver can also be priced as by-products. Therefore, it is of great significance to realize the efficient recovery of multiple metal minerals and improve the comprehensive economic benefit through the innovation of mineral processing technology.

[0004] At present, the flotation process commonly used for sulfur concentrate in the prior art is to grind the sulfur concentrate slurry, add lime for slurry conditioning, then sequentially add copper sulfate, ethylthiuram sodium and butyl xanthate for flotation operation, and finally obtain a sulfur concentrate containing lead and zinc. The following shortcomings exist: 1) The technology directly targets the sulfur concentrate slurry for flotation operation, and the sulfur concentrate slurry often contains a large amount of mineral processing reagent components. Since the commonly used xanthate collector is used for sulfur selection in the industry, there is a large amount of xanthate component in the slurry. If no technical means is used for drug removal and sulfur suppression in advance, the flotation of the slurry will cause a large amount of sulfur to float due to the xanthate, resulting in the failure of the separation operation. In addition, the addition of a large amount of lime in a strong alkaline environment suppresses the sulfur component. Not only is the cost of the lime reagent high, but also the mineral processing wastewater is alkaline, which causes environmental problems; 2) Ethylthiuram sodium and butyl xanthate are used for lead and zinc recovery. The butyl xanthate has strong collecting ability and lacks selectivity, which easily causes the mis-collection of sulfur components. This 'heavy suppression and heavy flotation' method is not conducive to the improvement of the flotation index; 3. The technology does not explore the gold and silver recovery effect, and further optimization is necessary.

[0005] Therefore, it is necessary to explore a new flotation process to effectively solve the adverse effects of residual reagent components in the sulfur concentrate, break the technical barriers of sulfur concentrate drug removal, and achieve the inhibition of sulfur components under neutral conditions, and realize the efficient enrichment of lead, zinc, gold, silver and other multi-metal elements. SUMMARY

[0006] The application aims to provide a flotation method for comprehensively recovering lead, zinc, gold and silver from sulfur concentrate after lead-zinc separation. The application adopts a grinding-flotation beneficiation process, fully utilizes the role of grinding in improving the monomer dissociation degree between different minerals and stripping drugs, and uses efficient sulfur inhibitors and efficient lead, zinc, gold and silver collectors for comprehensive recovery, effectively solves the interference of residual reagent in the sulfur concentrate, breaks the technical barriers of sulfur concentrate drug removal, and realizes the inhibition of sulfur components under neutral conditions, and realizes the efficient enrichment of lead, zinc, gold, silver and other multi-metal elements.

[0007] To achieve the above-mentioned purpose, the application provides the following technical scheme:

[0008] The application provides a flotation method for comprehensively recovering lead, zinc, gold and silver from sulfur concentrate, which comprises the following steps:

[0009] 1) Obtain sulfur concentrate filter press products or dry products;

[0010] 2) While grinding the sulfur concentrate filter press products or dry products, add sodium sulfide to perform combined drug removal and pre-thicken, and obtain a slurry;

[0011] 3) Add a sulfur inhibitor to the slurry, fully stir, and then add a collector to perform roughing to obtain roughing concentrate and roughing tailings;

[0012] 4) Add the sulfur inhibitor of step 3) to the roughing concentrate to perform cleaning to obtain a concentrate product and cleaning tailings;

[0013] 5) Add the collector of step 3) to the roughing tailings to perform scavenging to obtain scavenging concentrate and final tailings.

[0014] Preferably, the flotation method further comprises: combining the cleaning tailings obtained in step 4) and the scavenging concentrate obtained in step 5) as middlings product and returning to step 3) for roughing operation.

[0015] In some specific embodiments, the sulfur concentrate filter press products or dry products have a sulfur concentrate main grade of 32-42%, a Pb grade of 0.2-1%, a Zn grade of 0.2-1%, a gold grade of 5.5-7.2 g / t, and a silver grade of 30-40 g / t.

[0016] Preferably, in step 2), the grinding fineness of the sulfur concentrate filter cake or dry product reaches 80-90% of -0.074 mm; the addition amount of sodium sulfide is 200-500 g / t.

[0017] The present application has the following two aspects of effects on grinding the sulfur concentrate filter cake or dry product: on the one hand, the grinding fineness is improved, which is beneficial to further dissociation of lead, zinc, gold, silver and other metal minerals and pyrite, and creates conditions for later sulfur inhibition flotation and comprehensive recovery; on the other hand, in the grinding process, the grinding medium and mineral particles continuously collide, extrude and grind, under which the reagents attached to the mineral surface gradually fall off with the mineral surface and expose new mineral surface, completing mechanical reagent removal and avoiding interference of residual reagents on the flotation process. Meanwhile, sodium sulfide is used as an adjusting agent, which has the effects of resolving the reagent film attached to the mineral surface and removing the reagent, and when added during grinding, it promotes the mechanical reagent removal, which is beneficial to enhancing the reagent removal effect; in addition, sodium sulfide has an inhibiting effect on pyrite, and an appropriate amount of sodium sulfide can activate lead, zinc, gold and silver minerals and improve the flotation froth structure.

[0018] Preferably, in step 3), the sulfur inhibitor is composed of sodium sulfite and sodium humate in equal proportions by mass, and the addition amount of the sulfur inhibitor is 800-2000 g / t; the fully stirring time is 5-10 min.

[0019] Preferably, in step 3), the addition amount of the collector is 80-300 g / t; the collector is CY collector or Z-200 collector or a combination of CY collector and Z-200 collector; the CY collector is a short-chain bis-alkyl dithiophosphate or a short-chain bis-alkyl dithiophosphoric acid, in which the number of carbon atoms in the alkyl group is 2-3; the Z-200 collector is ethyl thiourea.

[0020] It should be noted that CY collector has good collecting performance for lead, gold and silver, and Z-200 has good collecting performance for zinc, gold and silver, and it can be known that both of the reagents have good collecting performance for gold and silver, so the specific type of the collector can be determined according to the actual situation of lead and zinc in the sulfur concentrate, if the lead content is high, the proportion of CY is increased, and if the zinc content is high, the proportion of Z-200 is increased. Taking the sulfur concentrate filter cake or dry product used in some specific embodiments of the present application as an example, the specific proportion of CY and Z-200 is illustrated:

[0021] Example 1: when the lead grade in the sulfur concentrate is 0.2%≤lead grade≤0.3%, the lead content is low, and the recovery value is low, CY collector does not need to be added, only Z-200 needs to be added, and the mass ratio of CY to Z-200 is 0:1 at this time.

[0022] Example 2: when 0.2%≤zinc grade≤0.3% in the sulfur concentrate, due to the low zinc content, the recovery value is low, Z-200 collector does not need to be added, only CY needs to be added, at this time the mass ratio of CY and Z-200 is 1:0;

[0023] Example 3: when 0.2%≤lead grade≤0.3% and 0.2%≤zinc grade≤0.3% in the sulfur concentrate, at this time the lead and zinc contents are both low, the recovery value is low, at this time any one of CY and Z-200 or a medicament combined in any ratio of the two can be added, so as to realize the enrichment of gold and silver;

[0024] Example 4: when 0.3%<lead grade≤1% and 0.3%<zinc grade≤1% and the absolute value |lead-zinc|≤0.2% in the sulfur concentrate, it is considered that the lead and zinc both have recovery value and the lead and zinc content levels are basically the same, the two medicaments are used at the same time, at this time the mass ratio of CY and Z-200 is 1:1;

[0025] Example 5: when 0.3%<lead grade≤1% and 0.3%<zinc grade≤1% and the absolute value |lead-zinc|>0.2% in the sulfur concentrate, it is considered that the lead and zinc both have recovery value and the lead and zinc content levels exist certain difference, CY and Z-200 two medicaments need to be added, when the lead grade>zinc grade, the amount of CY is increased, the amount of CY / the amount of Z-200 is greater than 1; when the lead grade<zinc grade, the amount of Z-200 is increased, the amount of Z-200 / the amount of CY is greater than 1.

[0026] Preferably, in step 4), the adding amount of the sulfur inhibitor is 200-800 g / t.

[0027] Preferably, in step 5), the adding amount of the collector is 20-80 g / t.

[0028] In some specific embodiments, in the concentrate product obtained in step 4), 5%<Pb+Zn<15%, Au>15 g / t, Ag>200 g / t, 30%<S<40%.

[0029] Since the process still belongs to sulfur concentrate re-election in principle, in order to protect the concentrate grade, it is not appropriate to set too long a flotation operation process, otherwise the floating amount of sulfur component increases, which is not conducive to the improvement of concentrate index.

[0030] Principle of the application:

[0031] 1. In existing sulfide ore flotation processes, lime is commonly used as a depressant for pyrite. However, lime's depressant effect on pyrite is very strong, and since pyrite is also a major carrier mineral for gold and silver, using lime to suppress pyrite significantly inhibits the recovery of closely associated gold and silver minerals. This invention uses a combination of sodium sulfite and sodium humate for sulfur suppression. This organic depressant has good selectivity and strong targeting, and when used in conjunction with the inorganic depressant, it complements each other and exerts a synergistic effect. Compared to lime, it has a stronger sulfur suppression effect and significantly reduces the amount of reagents required. Furthermore, this combined reagent system has minimal impact on the pulp pH and exhibits good environmental benefits.

[0032] 2. In existing sulfide ore flotation, xanthate reagents are often used as collectors for pyrite. However, xanthate reagents have strong collecting power but lack selectivity, so they are not suitable as collectors for enriching lead, zinc, gold, and silver from sulfide concentrates.

[0033] This invention uses Z-200, CY, or a combination of both as collectors. Z-200, also known as ethyl thiocyanate, has good selectivity, but weak collecting ability for pyrite. However, it exhibits good collecting performance for gold and silver, enabling the enrichment of valuable minerals such as copper, zinc, gold, and silver in the concentrate, thus reducing the pyrite content. CY collector is a short-chain dialkyl dithiophosphate or short-chain dialkyl dithiophosphate, also exhibiting good selectivity. While it has weak collecting ability for pyrite, it also demonstrates good collecting performance for gold and silver, enabling the enrichment of valuable minerals such as lead, gold, and silver in the concentrate, thus reducing the pyrite content. When Z-200 and CY are used in combination, a synergistic effect is produced, compensating for the insufficient collecting ability of Z-200 for lead minerals and CY for zinc minerals, while enhancing the selectivity and collecting performance for gold and silver. Furthermore, both agents have good foaming properties; when used in combination, the foam structure is further optimized compared to either agent alone, eliminating the need for additional foaming agents.

[0034] The beneficial effects of this invention are:

[0035] 1. This invention involves adding sodium sulfide for combined descaling and pre-conditioning of sulfur concentrate filter products or dry products during grinding. Then, sodium sulfite and sodium humate are used as sulfur inhibitors, and CY and / or Z-200 are used as collectors. Flotation yields a comprehensive concentrate with high lead, zinc, gold, and silver grades (5% < Pb + Zn < 15%, Au > 15 g / t, Ag > 200 g / t, 30% < S < 40%), which can be used as a gold concentrate for comprehensive pricing and has high economic benefits.

[0036] 2. This invention uses sulfur concentrate filter press samples, that is, the sulfur concentrate slurry is dewatered and filtered in advance to remove a large amount of reagents, which can greatly reduce the subsequent reagent consumption and operation difficulty.

[0037] 3. This invention achieves combined de-reagent pretreatment through grinding and the addition of sodium sulfide during grinding, effectively solving the problem of interference from residual reagents during sulfur concentrate flotation; at the same time, sodium sulfide can inhibit sulfur and activate lead, zinc, gold and silver minerals, improving the foam structure.

[0038] 4. This invention uses sodium sulfite and sodium humate as sulfur inhibitors, achieving efficient inhibition of sulfur components under neutral conditions, with small reagent dosage and environmental friendliness.

[0039] 5. This invention uses CY collector and / or Z-200 collector to achieve efficient recovery of multiple metal elements such as lead, zinc, gold, and silver. It is also highly applicable and can flexibly adjust the dosage and ratio according to changes in the properties of raw materials. Both agents have good foaming properties, eliminating the need for additional foaming agents and saving on foaming agent costs.

[0040] 6. All the agents used in this invention are green agents and have no risk of environmental pollution.

[0041] 7. This invention solves the problem of large amounts of sulfur floating up during the flotation recovery of other valuable metal minerals in sulfur concentrate. It achieves comprehensive enrichment of gold and silver on the basis of completing the enrichment of lead and zinc, and further improves the comprehensive recovery rate and value realization rate of multiple metal minerals. Attached Figure Description

[0042] Figure 1 This is a flow chart of the flotation process of the present invention. Detailed Implementation

[0043] To make the technical solution of the present invention clearer, the present invention will now be further explained and described in conjunction with specific embodiments.

[0044] Example 1

[0045] The sulfur concentrate filter press product used in this embodiment has the following composition: sulfur concentrate main grade 36.18%, Pb grade 0.47%, Zn grade 0.61%, gold grade 6.1 g / t, and silver grade 35.15 g / t. The sulfur concentrate filter press product is then subjected to flotation, and the specific steps are as follows:

[0046] 1) Grind the sulfur concentrate filter press product. At this time, add 400g / t of sodium sulfide to the grinding equipment simultaneously for combined de-drug treatment and pre-conditioning. When the grinding fineness of the sulfur concentrate filter press product reaches -0.074mm, accounting for 85%, it enters the slurry mixing tank.

[0047] 2) Add 1200g / t of sulfur inhibitor to the slurry mixing tank. The sulfur inhibitor is composed of sodium sulfite and sodium humate in equal mass ratio. After stirring for 8 minutes, the mixture is introduced into the flotation operation area.

[0048] 3) Add 120 g / t of a combined collector to the roughing flotation area for roughing. The combined collector consists of sodium diethyl dithiophosphate and Z-200 collector in a 1:1 mass ratio. After roughing, the frothy product is used as the rough concentrate and proceeds to the next cleaning operation; the unresolved slurry is used as the roughing tailings and proceeds to the next scavenging operation.

[0049] 4) Add 400g / t of the sulfur inhibitor described in step 2) to the beneficiation area and beneficiate the rough concentrate product. The foam product obtained after beneficiation is the final concentrate product, and the unrefined slurry is used as beneficiation tailings.

[0050] 5) Add 40g / t of the combined collector described in step 3) to the scavenging operation area to scaveng and separate the roughing tailings. The froth product obtained after scavenging is the scavenging concentrate. The scavenging concentrate is mixed with the cleaned tailings in the cleaning operation as the middlings product and returned to the roughing operation area. The slurry that is not separated in the scavenging operation is the final tailings.

[0051] According to the test results, the concentrate product obtained in this embodiment has a Pb grade of 4.34%, a Zn grade of 7.00%, an Au grade of 15.20 g / t, an Ag grade of 296.00 g / t, and a S grade of 35%.

[0052] Example 2

[0053] The sulfur concentrate filter press product used in this embodiment has a main sulfur grade of 40.1%, a Pb grade of 0.38%, a Zn grade of 0.52%, a gold grade of 6.3 g / t, and a silver grade of 32.98 g / t. The sulfur concentrate filter press product was subjected to flotation using the method described in Example 1. The final concentrate product had a Pb grade of 2.92%, a Zn grade of 4.20%, an Au grade of 15.60 g / t, an Ag grade of 290.00 g / t, and a sulfur grade of 34%.

[0054] Example 3

[0055] The sulfur concentrate filter press product used in this embodiment has a main sulfur content of 35.97%, a Pb content of 0.55%, a Zn content of 0.75%, a gold content of 6.5 g / t, and a silver content of 34.58 g / t. The sulfur concentrate filter press product was subjected to flotation using the method described in Example 1. The final concentrate product had a Pb content of 5.72%, a Zn content of 8.20%, an Au content of 16.00 g / t, an Ag content of 275.00 g / t, and a sulfur content of 38%.

[0056] Example 4

[0057] The sulfur concentrate filter press product used in this embodiment has a main sulfur content of 38.56%, a Pb content of 0.76%, a Zn content of 0.85%, a gold content of 5.8 g / t, and a silver content of 32.57 g / t. The sulfur concentrate filter press product was subjected to flotation using the method described in Example 1. The final concentrate product had a Pb content of 5.41%, a Zn content of 9.47%, an Au content of 15.70 g / t, an Ag content of 228.00 g / t, and a sulfur content of 33%.

[0058] Example 5

[0059] The sulfur concentrate filter press product used in this embodiment has a main sulfur content of 39.52%, a Pb content of 0.62%, a Zn content of 0.48%, a gold content of 7.1 g / t, and a silver content of 37.68 g / t. The sulfur concentrate filter press product was subjected to flotation using the method described in Example 1. The final concentrate product had a Pb content of 5.01%, a Zn content of 6.12%, an Au content of 22.10 g / t, an Ag content of 348.00 g / t, and a sulfur content of 35%.

[0060] Example 6

[0061] The sulfur concentrate filter press product used in this embodiment has a main sulfur content of 34.88%, a Pb content of 0.71%, a Zn content of 0.54%, a gold content of 6.9 g / t, and a silver content of 36.81 g / t. The sulfur concentrate filter press product was subjected to flotation using the method described in Example 1. The final concentrate product had a Pb content of 6.92%, a Zn content of 2.98%, an Au content of 22.20 g / t, an Ag content of 270.00 g / t, and a sulfur content of 32%.

[0062] Example 7

[0063] The sulfur concentrate filter press product used in this embodiment has the following composition: sulfur concentrate grade 37.24%, Pb grade 0.23%, Zn grade 0.44%, gold grade 5.9 g / t, and silver grade 32.37 g / t. The sulfur concentrate filter press product is then subjected to flotation, and the specific steps are as follows:

[0064] 1) Grind the sulfur concentrate filter press product. At this time, add 400g / t of sodium sulfide to the grinding equipment simultaneously for combined de-drug treatment and pre-conditioning. When the grinding fineness of the sulfur concentrate filter press product reaches -0.074mm, accounting for 80%, it enters the slurry mixing tank.

[0065] 2) Add 2000g / t of sulfur inhibitor composed of sodium sulfite and sodium humate in the same mass ratio to the slurry mixing tank, stir thoroughly for 8 minutes, and then enter the flotation operation area.

[0066] 3) Add 150g / t of Z-200 collector to the roughing flotation area for roughing. After roughing, the frothy product is used as the rough concentrate and proceeds to the next cleaning operation; the unresolved slurry is used as the roughing tailings and proceeds to the next scavenging operation.

[0067] 4) Add 400g / t of the sulfur inhibitor described in step 2) to the beneficiation area and beneficiate the rough concentrate product. The foam product obtained after beneficiation is the final concentrate product, and the unrefined slurry is used as beneficiation tailings.

[0068] 5) Add 60g / t of Z-200 collector to the scavenging operation area to scaveng and separate the roughing tailings. The froth product obtained after scavenging is the scavenging concentrate. The scavenging concentrate is mixed with the selected tailings in the cleaning operation as middlings and returned to the roughing operation area. The slurry that is not separated in the scavenging operation is the final tailings.

[0069] According to the test results, the concentrate product obtained in this embodiment has the following properties: Pb grade is 1.74%, Zn grade is 5.63%, Au grade is 16.70 g / t, Ag grade is 247.00 g / t, and S grade is 36.81%.

[0070] Example 8

[0071] The sulfur concentrate filter press product used in this embodiment has the following composition: sulfur concentrate main grade 36.43%, Pb grade 0.62%, Zn grade 0.27%, gold grade 6.8 g / t, and silver grade 37.49 g / t. The sulfur concentrate filter press product is then subjected to flotation, and the specific steps are as follows:

[0072] 1) Grind the sulfur concentrate filter press product. At this time, add 400g / t of sodium sulfide to the grinding equipment simultaneously for combined de-drug treatment and pre-conditioning. When the grinding fineness of the sulfur concentrate filter press product reaches -0.074mm, accounting for 85%, it enters the slurry mixing tank.

[0073] 2) Add 1800g / t of a sulfur inhibitor, consisting of sodium sulfite and sodium humate in equal mass ratios, to the slurry mixing tank, and stir thoroughly for 8 minutes before entering the flotation operation area.

[0074] 3) Add 200 g / t of diethyl dithiophosphate to the roughing flotation area for roughing. After roughing, the frothy product is used as the rough concentrate and proceeds to the next cleaning operation; the unresolved slurry is used as the roughing tailings and proceeds to the next scavenging operation.

[0075] 4) Add 600g / t of the sulfur inhibitor described in step 2) to the beneficiation area and beneficiate the rough concentrate product. The foam product obtained after beneficiation is the final concentrate product, and the unrefined slurry is used as beneficiation tailings.

[0076] 5) Add 50g / t of diethyl dithiophosphate to the scavenging area to scaveng and separate the roughing tailings. The frothy product obtained after scavenging is the scavenging concentrate. The scavenging concentrate is mixed with the cleaned tailings from the cleaning operation as middlings and returned to the roughing area. The slurry that is not separated in the scavenging operation is the final tailings.

[0077] According to the test results, the concentrate product obtained in this embodiment has the following properties: Pb grade of 5.88%, Zn grade of 2.60%, Au grade of 20.54 g / t, Ag grade of 331.80 g / t, and S grade of 34.47%.

[0078] Example 9

[0079] The sulfur concentrate filter press product used in this embodiment has the following composition: sulfur concentrate main grade 39.15%, Pb grade 0.24%, Zn grade 0.27%, gold grade 6.5 g / t, and silver grade 35.93 g / t. The sulfur concentrate filter press product is then subjected to flotation, and the specific steps are as follows:

[0080] 1) Grind the sulfur concentrate filter press product. At this time, add 400g / t of sodium sulfide to the grinding equipment simultaneously for combined de-drug treatment and pre-conditioning. When the grinding fineness of the sulfur concentrate filter press product reaches -0.074mm, accounting for 90%, it enters the slurry mixing tank.

[0081] 2) Add 2000g / t of a sulfur inhibitor, consisting of sodium sulfite and sodium humate in equal mass ratios, to the slurry mixing tank, and stir thoroughly for 8 minutes before introducing it into the flotation operation area.

[0082] 3) Add 180 g / t of sodium diethyl dithiophosphate, Z-200, or a combination of sodium diethyl dithiophosphate and Z-200 in any ratio to the roughing flotation zone for roughing. After roughing, the frothy product is used as the rough concentrate and proceeds to the next cleaning operation; the unresolved slurry is used as the roughing tailings and proceeds to the next scavenging operation.

[0083] 4) Add 500g / t of sulfur inhibitor in the beneficiation area with a mass ratio of sodium sulfite and sodium humate, and beneficiate the rough concentrate product. The foam product obtained after beneficiation is the final concentrate product, and the unreconstituted slurry is used as beneficiation tailings.

[0084] 5) Add 80g / t of the reagent described in step 3) of sodium diethyl dithiophosphate or Z-200, or a combination of sodium diethyl dithiophosphate and Z-200 in any ratio, to the scavenging area to separate the roughing tailings. The frothy product obtained after scavenging is the scavenging concentrate. The scavenging concentrate is mixed with the concentrate tailings from the cleaning operation and returned to the roughing area as middlings. The slurry that is not separated in the scavenging operation is used as the final tailings.

[0085] According to the test results, the concentrate product obtained in this embodiment has a Pb grade of 2.34%, a Zn grade of 2.90%, an Au grade of 18.74 g / t, an Ag grade of 264.50 g / t, and a S grade of 37.47%.

[0086] Example 10

[0087] The sulfur concentrate filter press product used in this embodiment has the following composition: sulfur concentrate main grade 37.85%, Pb grade 0.48%, Zn grade 0.86%, gold grade 6.4 g / t, and silver grade 36.53 g / t. The sulfur concentrate filter press product is then subjected to flotation, and the specific steps are as follows:

[0088] 1) Grind the sulfur concentrate filter press product. At this time, add 400g / t of sodium sulfide to the grinding equipment simultaneously for combined de-drug treatment and pre-conditioning. When the grinding fineness of the sulfur concentrate filter press product reaches -0.074mm, accounting for 85%, it enters the slurry mixing tank.

[0089] 2) Add 1400g / t of a sulfur inhibitor, consisting of sodium sulfite and sodium humate in equal mass ratio, to the slurry mixing tank, and stir thoroughly for 8 minutes before entering the flotation operation area.

[0090] 3) Add 150 g / t of a combined collector consisting of sodium diethyl dithiophosphate and Z-200 at a mass ratio of 1:2 to the roughing flotation zone for roughing. After roughing, the frothy product is obtained as the rough concentrate and proceeds to the next cleaning operation; the unresolved slurry is used as the roughing tailings and proceeds to the next scavenging operation.

[0091] 4) Add 800g / t of the sulfur inhibitor described in step 2) to the beneficiation area and beneficiate the rough concentrate product. The foam product obtained after beneficiation is the final concentrate product, and the unrefined slurry is used as beneficiation tailings.

[0092] 5) Add 60g / t of the combined collector described in step 3) to the scavenging area to scaveng and separate the roughing tailings. The frothy product obtained after scavenging is the scavenging concentrate. The scavenging concentrate is mixed with the concentrate tailings from the cleaning operation and returned to the roughing area as middlings. The slurry that is not separated in the scavenging operation is used as the final tailings.

[0093] According to the test results, the concentrate product obtained in this embodiment has the following properties: Pb grade of 3.54%, Zn grade of 6.90%, Au grade of 18.2 g / t, Ag grade of 277.34 g / t, and S grade of 36.42%.

[0094] Example 11

[0095] The sulfur concentrate filter press product used in this embodiment has the following composition: sulfur concentrate main grade 34.51%, Pb grade 0.78%, Zn grade 0.44%, gold grade 6.7 g / t, and silver grade 33.87 g / t. The sulfur concentrate filter press product is then subjected to flotation, and the specific steps are as follows:

[0096] 1) Grind the sulfur concentrate filter press product. At this time, add 400g / t of sodium sulfide to the grinding equipment simultaneously for combined de-drug treatment and pre-conditioning. When the grinding fineness of the sulfur concentrate filter press product reaches -0.074mm, accounting for 85%, it enters the slurry mixing tank.

[0097] 2) Add 1800g / t of sulfur inhibitor composed of sodium sulfite and sodium humate in the same mass ratio to the slurry mixing tank, stir thoroughly for 8 minutes and then enter the flotation operation area.

[0098] 3) Add 150 g / t of a combined collector consisting of sodium diethyl dithiophosphate and Z-200 at a mass ratio of 2:1 to the roughing flotation zone for roughing. After roughing, the frothy product is used as the rough concentrate and proceeds to the next cleaning operation; the unresolved slurry is used as the roughing tailings and proceeds to the next scavenging operation.

[0099] 4) Add 200g / t of the sulfur inhibitor described in step 2) to the beneficiation area and beneficiate the rough concentrate product. The foam product obtained after beneficiation is the final concentrate product, and the unrefined slurry is used as beneficiation tailings.

[0100] 5) Add 60g / t of the combined collector described in step 3) to the scavenging area to scaveng and separate the roughing tailings. The frothy product obtained after scavenging is the scavenging concentrate. The scavenging concentrate is mixed with the concentrate tailings from the cleaning operation and returned to the roughing area as middlings. The slurry that is not separated in the scavenging operation is used as the final tailings.

[0101] According to the test results, the concentrate product obtained in this embodiment has a Pb grade of 6.67%, a Zn grade of 5.28%, an Au grade of 20.44 g / t, an Ag grade of 297.58 g / t, and a S grade of 34.76%.

[0102] In summary, this invention is simple and easy to implement, highly operable, and can yield significant economic benefits. Taking a lead-zinc ore beneficiation plant in Hunan Province as an example, after using this process, the gold content of the original sulfur concentrate decreased from 6-7 g / t to 5-6 g / t. While meeting the requirement that the gold content in the sulfur concentrate should not be less than 5 g / t, it also produced an additional comprehensive gold concentrate product rich in lead, zinc, gold, and silver, resulting in an annual increase in efficiency of 10 million yuan.

Claims

1. A flotation method for the comprehensive recovery of lead, zinc, gold, and silver from sulfur concentrate, comprising the following steps: 1) Obtain sulfur concentrate filter press products or dry products; 2) Sodium sulfide is added while grinding the sulfur concentrate filter press product or dry material product, and combined de-drug treatment and pre-mixing are carried out to obtain the slurry; 3) Add a sulfur inhibitor to the slurry, stir thoroughly, then add a collector for roughing to obtain a roughing concentrate and roughing tailings; the sulfur inhibitor is composed of sodium sulfite and sodium humate in equal mass ratios, and the amount of sulfur inhibitor added is 800~2000 g / t; the stirring time is 5~10 min; the amount of collector added is 80~300 g / t; the collector is CY collector or Z-200 collector or a combination of both; the CY collector is short-chain dialkyl dithiophosphate or short-chain dialkyl dithiophosphate, wherein the number of carbon atoms in the alkyl group is 2~3; the Z-200 collector is ethyl thiocyanate; the specific type of collector added is determined according to the actual situation of lead and zinc in the sulfur concentrate, specifically: When the lead content in the sulfur concentrate is 0.2% ≤ lead ≤ 0.3%, only Z-200 collector should be added. When the zinc grade in the sulfur concentrate is 0.2% ≤ zinc ≤ 0.3%, only CY collector is added; When the lead grade in the sulfur concentrate is 0.2% ≤ lead grade ≤ 0.3% and the zinc grade is 0.2% ≤ zinc grade ≤ 0.3%, CY collector or Z-200 collector or a combination of CY collector and Z-200 collector in any proportion should be added. When the lead grade in the sulfur concentrate is 0.3% < lead grade ≤ 1% and the zinc grade is 0.3% < zinc grade ≤ 1%, and the absolute value |lead-zinc| ≤ 0.2%, a combination agent consisting of CY collector and Z-200 collector in a mass ratio of 1:1 is added. When the lead grade in the sulfur concentrate is 0.3% < lead grade ≤ 1% and the zinc grade is 0.3% < zinc grade ≤ 1%, and the absolute value |lead-zinc| > 0.2%, then two reagents, CY and Z-200, need to be added. When the lead grade > zinc grade, the dosage of CY should be increased, and the ratio of CY dosage to Z-200 dosage should be greater than 1. When the lead grade < zinc grade, the dosage of Z-200 should be increased, and the ratio of Z-200 dosage to CY dosage should be greater than 1. 4) Add the sulfur inhibitor described in step 3) to the roughing concentrate for further cleaning to obtain concentrate product and cleaned tailings; the grade of the concentrate product is: 5% < Pb + Zn < 15%, Au > 15 g / t, Ag > 200 g / t, 30% < S < 40%; 5) Add the collector described in step 3) to the roughing tailings and perform scavenging to obtain scavenged concentrate and final tailings.

2. The flotation method according to claim 1, characterized in that, In step 1), the sulfur concentrate filter press product or dry product has a main sulfur concentrate grade of 32-42%, a Pb grade of 0.2-1%, a Zn grade of 0.2-1%, a gold grade of 5.5-7.2 g / t, and a silver grade of 30-40 g / t.

3. The flotation method according to claim 1, characterized in that, In step 2), the grinding fineness of the sulfur concentrate filter press product or dry material product reaches -0.074mm, accounting for 80~90%; the amount of sodium sulfide added is 200~500g / t.

4. The flotation method according to claim 1, characterized in that, In step 4), the amount of sulfur inhibitor added is 200~800g / t.

5. The flotation method according to claim 1, characterized in that, In step 5), the amount of the collector added is 20~80g / t.

6. The flotation method according to any one of claims 1 to 5, characterized in that, The flotation method further includes: combining the selected tailings obtained in step 4) with the scavenged concentrate obtained in step 5) as middlings and returning them to step 3) for roughing.

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