A flotation method for sulfur-containing copper-zinc ore

Abstract

This invention discloses a flotation method for sulfur-bearing copper-zinc ore, belonging to the field of mineral processing technology. The method involves conditioning and grinding the sulfur-bearing copper-zinc ore to obtain a finely ground slurry. This finely ground slurry is then mixed with flotation reagents including a copper collector for copper flotation. The copper flotation tailings are then subjected to wet magnetic separation. The magnetic separation tailings are mixed with flotation reagents including a zinc activator, a zinc collector, a zinc frother, and a lime depressant for zinc flotation, yielding zinc concentrate and zinc flotation tailings. Sulfur flotation is then performed using a mixture of flotation reagents including a sulfur activator, a sulfur collector, a froth modifier, and a sulfur frother, yielding sulfur concentrate and tailings. The sulfur activator is a composition of ammonium bicarbonate and copper sulfate in a mass ratio of 5-20:1, with a dosage of 110-220 g / t. This method not only reduces reagent costs and increases sulfur concentrate recovery, but also provides better flotation results, simplifies operation, and allows for more precise control of flotation froth.

Description

Technical Field

[0001] This invention relates to a flotation method for sulfur-containing copper-zinc ore, belonging to the field of mineral processing technology. Background Technology

[0002] Pyrite is a major carrier of sulfur in nature and an important source of sulfuric acid. It is widely distributed in my country, found in most parts of the country. Pyrite mainly consists of pyrite and pyrrhotite, which differ in structure and properties. Pyrite has the chemical formula FeS₂, a sulfur content of 53.33%, is non-magnetic, stable, and not easily oxidized. Pyrrhotite has the chemical formula Fe₂S₂. 1-x S and x are generally 0~0.223, and the sulfur content is 39%~40%. As the chemical formula shows, its structure contains vacancies, which is the fundamental reason for its magnetic properties. Therefore, magnetic separation can be used to remove the strongly magnetic pyrrhotite beforehand. In nature, pyrite often occurs in association with minerals such as galena, sphalerite, chalcopyrite, and magnetite, making effective separation difficult. Flotation is the most commonly used method for processing pyrite, mainly by adding collectors, frothers, and activators, utilizing the differences in hydrophobicity of the mineral surfaces to achieve separation. However, during the flotation process, the stability and selectivity of the flotation process are closely related to the flotation froth. With the intensification of ore mining, the feed ore is gradually becoming leaner and more complex, with an increased content of fine-grained minerals, further increasing the difficulty of controlling the flotation froth.

[0003] In production, pyrite beneficiation often faces problems such as uncontrolled flotation foam, mainly manifested in the following aspects: First, excessive foam volume and thick foam layers lead to "flotation runaway," affecting production stability. Second, insufficient foam mineralization and easy defoaming in the pyrite flotation system result in the inability to recover the target mineral, causing metal loss. Therefore, the flotation foam problem has always been a technical challenge in pyrite flotation.

[0004] Several methods exist for controlling flotation foam. The most common method is to adjust parameters such as the flotation machine's skimming speed and liquid level to control the flotation foam layer thickness. However, this only addresses the surface layer and doesn't solve deeper problems. Another method involves adding frothers such as alcohols and phenols, as well as defoamers like diesel fuel. However, these agents lack selectivity, and while controlling foam, they may also lead to the loss of the target mineral. Furthermore, they are typically used in large quantities, increasing production costs.

[0005] In summary, the existing foam control methods mainly have the following problems: (1) lack of refined control of foam behavior; (2) high cost and poor effect; (3) lack of specific control of foam behavior in pyrite flotation system; (4) often require modification of on-site production equipment or addition of multiple stages, increasing the difficulty of operation on the production site.

[0006] Because of these problems, developing a combination reagent that is low-cost, effective, easy to operate, and can precisely control the froth behavior of pyrite flotation has significant industrial application value. Summary of the Invention

[0007] To address issues such as low flotation froth volume, high sulfur loss rate in tailings, and high reagent costs in production sites, one objective of this invention is to provide a flotation method for sulfur-containing copper-zinc ores. By employing the process flow of this invention, through control of mineral particle size, control of reagents in the zinc flotation stage, and the synergistic use of sulfur activators and other technical features in the sulfur flotation stage, not only can reagent costs be reduced and sulfur concentrate recovery rate increased, but the flotation effect is also better, the operation is simpler, and flotation froth can be more precisely controlled. The effect is particularly significant when processing high-sulfur copper-zinc ores.

[0008] To achieve the above objectives, a first aspect of the present invention provides a flotation method for sulfur-containing copper-zinc ore, the method comprising:

[0009] (1) The sulfur-containing copper-zinc ore is subjected to slurry preparation and grinding to obtain fine grinding slurry;

[0010] (2) The finely ground slurry is mixed with flotation reagents including copper collectors to carry out copper flotation, thereby obtaining copper concentrate and copper flotation tailings;

[0011] (3) The copper flotation tailings are subjected to wet magnetic separation to obtain pyrrhotite concentrate and magnetic separation tailings;

[0012] (4) The magnetic separation tailings are mixed with flotation reagents including zinc activator, zinc collector, zinc frother and lime inhibitor to carry out zinc flotation to obtain zinc concentrate and zinc flotation tailings;

[0013] (5) The zinc flotation tailings are subjected to particle size classification or secondary grinding to obtain a slurry to be flotated; the slurry to be flotated is mixed with flotation reagents including sulfur activator, sulfur collector, froth modifier and sulfur frother to carry out sulfur flotation to obtain sulfur concentrate and tailings; the sulfur activator is a combination of ammonium bicarbonate and copper sulfate with a mass ratio of 5~20:1, the amount of sulfur activator is 110~220g / t, the sulfur collector is butyl xanthate, and the froth modifier is diesel oil.

[0014] The flotation principle of this invention is as follows: Pyrite coexists with chalcopyrite, sphalerite, galena, magnetite, and iron sphalerite, and direct beneficiation makes it difficult to separate pyrite from these associated minerals. Therefore, grinding is first used to liberate the ore monomers, followed by flotation separation of chalcopyrite. The flotation tailings are then subjected to magnetic separation to obtain pyrrhotite concentrate, followed by zinc flotation, and finally sulfur flotation, thus achieving efficient recovery of sulfur concentrate.

[0015] The purpose of performing magnetic separation before zinc flotation in this invention is twofold: first, to preferentially separate strongly magnetic pyrrhotite and less magnetite, thereby reducing the processing volume and reagent usage in the subsequent sulfur flotation stage; and second, to reduce the amount of magnetic tailings processed in the zinc flotation stage and lower the amount of lime used in this stage. Reducing the amount of lime used in the zinc flotation stage not only ensures the zinc flotation effect, but also, through the combined use of zinc activator, zinc collector, zinc frother, and lime depressant, provides a suitable flotation pulp environment for subsequent sulfur flotation, effectively reducing the amount of combined activator used in the sulfur flotation stage and further improving sulfur flotation efficiency.

[0016] Furthermore, in the beneficiation of pyrite from zinc tailings, the main flotation reagents used in this invention are sulfur activators, sulfur collectors, froth modifiers, and sulfur frothers. During the flotation process, compared to using ammonium bicarbonate or copper sulfate alone, the combined use of ammonium bicarbonate and copper sulfate in a mass ratio of 5-20:1 is more effective. This is mainly because the bicarbonate ions in ammonium bicarbonate can neutralize the lime at the front end, eliminate the precipitation and consumption of the collector by calcium ions, and prevent the formation of a hydrophilic coating film on the mineral surface, thus maintaining the surface activity of the pyrite. Simultaneously, the ammonium ions in ammonium bicarbonate can further enhance the activation effect of copper ions and regulate the pH of the pulp. The main reactions involved are as follows:

[0017]

[0018]

[0019]

[0020]

[0021] In the reaction formula, CuS is not an independent mineral, but rather copper ions embedded in the surface lattice of pyrite, forming a highly reactive CuFeS2-type surface layer. It is precisely the presence of active copper sites on the pyrite surface that makes the collector more effective at collecting pyrite. Furthermore, the collector butyl xanthate primarily makes the activated target mineral surface hydrophobic, thereby achieving the flotation of the target mineral. This flotation is mainly due to the chemical adsorption of xanthate ions from the butyl xanthate with metal ions on the mineral surface, forming xanthates.

[0022] Furthermore, when used in conjunction with the collector butyl xanthate, the ammonium ions in ammonium bicarbonate can catalyze the oxidation of butyl xanthate to generate bixanthate, further enhancing the collecting ability of butyl xanthate. Because xanthate ions and bixanthate co-adsorb on the surface of the target mineral, a hydrophobic layer is formed, allowing the target mineral to adhere to the bubbles and float. The main reactions involved are as follows:

[0023]

[0024]

[0025] The reagent kit designed in this invention, used in the flotation of pyrite, effectively improves the activation efficiency of pyrite and exhibits strong resistance to pH interference. It also allows for precise control of foam, reducing foam entrainment and improving foam structure. The main reason for reducing foam entrainment is that the carbonate ions in ammonium bicarbonate can eliminate the hydrophilic calcium film on the surface of pyrite, making it easier for bubbles to capture. Simultaneously, ammonium ions lower the pH of the pulp, further reducing the formation of hydrophilic substances such as ferric hydroxide on the pyrite surface. Furthermore, copper sulfate forms a highly reactive CuFeS2-type surface layer on the pyrite surface after the hydrophilic film is removed by ammonium bicarbonate. This not only provides adsorption sites for the collector but also further improves the hydrophobicity of the mineral surface, increasing the contact angle with the bubbles. This allows the mineral to adhere more firmly to the bubbles, forming a more stable foam structure. Since the target mineral is maximally attached to the bubbles, less foam is needed, thus reducing the likelihood of slime and gangue minerals being entrained by the foam. Furthermore, diesel oil is added as a foam modifier, which enhances the stability of the foam through synergistic effects with the foaming agent and sulfur activator. It also has a certain harvesting effect, which is beneficial for the recovery of pyrrhotite.

[0026] If the amount of ammonium bicarbonate is too low, the pyrite will not be sufficiently activated, leading to an increased loss rate of the pyrite concentrate. If the amount is too high, both the target and non-target minerals will be activated, and the pH of the pulp will decrease due to the neutralization effect of ammonium ions, which is detrimental to the flotation of pyrite. Therefore, the activation effect of ammonium bicarbonate can be maximized within the dosage range of this invention. Conversely, if the amount of copper sulfate is too high, the flotation foam will break down; the amount of copper sulfate within the range of this invention is beneficial for foam stability.

[0027] Furthermore, the flotation method provided by this invention not only requires lower reagent dosages but also achieves better flotation results. Moreover, the reagent pack of this invention can better control the loading of froth and pyrite, ensuring both sufficient froth volume and the removal of more pyrite.

[0028] As a preferred embodiment, the concentration of the finely ground slurry is 35-40 wt%. If the slurry concentration is too high, the amount of reagent used will decrease, but the selectivity will deteriorate; if the slurry concentration is too low, the amount of reagent used will increase.

[0029] As a preferred option, particles of -0.074 mm in the finely ground slurry account for ≥55% of the total solid particles. During monomer liberation, controlling the particle size of -0.074 mm particles in the finely ground slurry to ≥55% of the total solid particles allows pyrite to achieve monomer liberation from associated minerals within this particle size range, thereby improving the flotation performance of sulfur concentrate.

[0030] As a more preferred option, the -0.074 mm particles in the finely ground slurry account for ≥60% of the total solid particles by mass. Within this preferred range, the flotation performance of the sulfur concentrate can be further improved.

[0031] As a preferred embodiment, in the slurry to be flotated, particles with a size range of 0.037 mm to 0.074 mm account for ≥60% of the total solid particle mass. Within this particle size range, the combined activator (sulfur activator) is more effective. If the particle size is too fine, the slurry viscosity will increase, leading to agglomeration and other phenomena. If the particle size is too coarse, the target mineral will not float effectively, increasing the loss in the tailings.

[0032] As a preferred embodiment, the sulfur content in the sulfur-bearing copper-zinc ore is 10-17 wt%. This invention is more effective when processing sulfur-bearing copper-zinc ore with higher sulfur content.

[0033] As a preferred embodiment, the copper collector is selected from at least one of butylammonium black powder, 25# black powder, and ethyl thiocyanate.

[0034] As a preferred embodiment, the magnetic field strength of the wet magnetic separation is 0.1~0.2T. Under this preferred condition, pyrrhotite and a small amount of magnetite can be separated.

[0035] As a preferred embodiment, the zinc activator is copper sulfate and / or lead nitrate; the zinc collector is ethyl thiocyanate and / or butyl xanthate; and the zinc foaming agent is 25# black powder and / or 2# oil.

[0036] As a preferred embodiment, the sulfur foaming agent is 25# black powder and / or 2# oil.

[0037] As a preferred embodiment, the sulfur activator is a composition of ammonium bicarbonate and copper sulfate in a mass ratio of 6 to 15:1. Experiments have shown that under this preferred condition, the recovery rate of sulfur concentrate is better and the flotation effect is better. The mass ratio of ammonium bicarbonate to copper sulfate is further preferably 8 to 14:1, and even more preferably 9 to 12.

[0038] As a preferred embodiment, the dosage of the sulfur activator is 140-180 g / t, and more preferably 160-180 g / t. Experiments have shown that when the dosage of the sulfur activator is 160-180 g / t, the recovery rate of sulfur concentrate is better and the flotation effect is better.

[0039] As a preferred embodiment, the pH value of the copper flotation is 6-7, and the amount of copper collector used is 1-5 g / t. The pH value is further preferably 6-6.5.

[0040] As a preferred embodiment, the pH value of the zinc flotation is 7-8, the amount of zinc activator is 100-200 g / t, the amount of zinc collector is 1-5 g / t, the total amount of zinc frother is 1-5 g / t, and the amount of lime is 800-1000 g / t.

[0041] As a more preferred embodiment, the pH value of the zinc flotation is 7~7.5, the amount of zinc activator is 100~150g / t, the amount of zinc collector is 2~5g / t, the total amount of zinc frother is 1~5g / t, and the amount of lime is 900~1000g / t.

[0042] As a preferred embodiment, the zinc foaming agent is a combination of 25# black powder and 2# oil in a mass ratio of 2~4:1. A further preferred mass ratio of 25# black powder to 2# oil is 3~4:1.

[0043] As a preferred embodiment, the pH value of the sulfur flotation is 7-8, the total amount of sulfur frother is 1-5 g / t, the amount of sulfur collector is 20-300 g / t, and the amount of foam modifier is 1-5 g / t.

[0044] As a more preferred embodiment, the pH value of the sulfur flotation is 6.5-7, the dosage of sulfur activator is 140-170 g / t, the total dosage of sulfur frother is 2-5 g / t, the dosage of sulfur collector is 100-150 g / t, and the dosage of froth modifier is 3-5 g / t. Experiments have shown that under this preferred condition, froth can be more precisely controlled, the recovery rate of pyrite can be improved, and the flotation effect is better.

[0045] As a further preferred embodiment, the total dosage of the sulfur frother is 3-5 g / t, the dosage of the sulfur collector is 130-150 g / t, and the dosage of the froth modifier is 3-5 g / t. Experiments have shown that under this preferred condition, the recovery rate and sulfur grade of pyrite can be further improved, resulting in better flotation performance.

[0046] As a preferred option, the sulfur foaming agent is a combination of No. 2 oil and No. 25 black powder in a mass ratio of 1:1 to 5. A further preferred mass ratio of No. 2 oil to No. 25 black powder is 1:3 to 5. Even more preferred is 1:4 to 5. Experiments have shown that under these preferred conditions, the recovery rate and sulfur grade of pyrite can be further improved.

[0047] As a preferred embodiment, the sulfur flotation separation employs a flotation process consisting of one roughing, one cleaning, and two scavenging stages. No additional reagents are required for either the cleaning or scavenging operations.

[0048] In this invention, the amounts of copper collector, zinc activator, zinc collector, zinc foaming agent, lime inhibitor, sulfur activator, sulfur collector, foam modifier, and sulfur foaming agent are all relative to the amount of sulfur-containing copper-zinc ore.

[0049] Compared with the prior art, the present invention has at least the following advantages:

[0050] (1) The method of the present invention can effectively control the froth state of pyrite flotation by simply adding the reagent group of the present invention, without changing the process flow at the production site or replacing or modifying the existing equipment. It has good process adaptability and ease of operation.

[0051] (2) Compared with the use of copper sulfate or ammonium bicarbonate alone, the combined agent provided by the present invention can still show superior foam control performance while significantly reducing the dosage. It has the advantages of low dosage and outstanding effect, and is conducive to reducing agent cost and improving economic benefits.

[0052] (3) The reagent group described in this invention is added only in the coarse selection stage, without the need to add it separately at multiple work points. This simplifies the reagent addition system, reduces the number of operation steps, reduces the labor intensity of workers, and improves the convenience and controllability of operation.

[0053] (4) After using the reagent kit of the present invention, the acidity and alkalinity of the pulp can be effectively adjusted, so that the pH value is reduced to the neutral or weakly alkaline range, thereby reducing the corrosive effect on the flotation equipment, extending the service life of the equipment, and improving the flotation environment of pyrite.

[0054] (5) The reagent kit of the present invention can achieve precise control of flotation foam, reduce the amount of flotation reagent and production cost, and improve the flotation recovery rate of sulfur concentrate, thereby effectively solving the drawbacks of existing technologies in controlling flotation foam and providing a brand-new solution for controlling flotation foam. Attached Figure Description

[0055] Figure 1 This is a process flow diagram of the present invention.

[0056] Figure 2This is a comparison diagram of the foaming effects of Comparative Example 1 and Example 18 of the present invention during the sulfur flotation stage. Figure 2 The left side of the image shows the foam effect in Comparative Example 1. Figure 2 The right side of the figure shows the foam effect of Example 18. As can be seen from the figure, when using the flotation reagent of the present invention, the flotation foam can be controlled more precisely. Detailed Implementation

[0057] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0058] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments. Obviously, the embodiments described below are only a part of the embodiments, and all other embodiments obtained by those skilled in the art without creative effort are still within the scope of protection of the present invention.

[0059] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0060] The following examples only compare the sulfur grade and sulfur loss rate in the tailings. The lower the sulfur grade and loss rate in the tailings, the better the effect of the corresponding reagent and the better the control of flotation foam.

[0061] Example 1

[0062] Raw ore: Sulfur-containing copper-zinc ore with a sulfur content of 16 wt%.

[0063] (1) The sulfur-containing copper-zinc ore is subjected to slurry preparation and grinding to obtain fine grinding slurry; the particles with a diameter of -0.074 mm account for ≥60% of the total solid particles in the fine grinding slurry;

[0064] (2) Add 5g / t of butanol black powder to the finely ground slurry and carry out copper flotation. The pH value is 6.2 to obtain copper concentrate and copper flotation tailings.

[0065] (3) The copper flotation tailings are subjected to wet magnetic separation (magnetic field strength of 0.15T) to obtain pyrrhotite concentrate and magnetic separation tailings;

[0066] (4) Add copper sulfate (100g / t), ethyl thiocyanate (5g / t), No. 2 oil (1g / t), No. 25 black powder (3g / t) and lime (1000g / t) to the magnetic separation tailings for zinc flotation (pH 7.2) to obtain zinc concentrate and zinc flotation tailings;

[0067] (5) The zinc flotation tailings are classified by particle size to obtain a flotation slurry with particles ranging from 0.037 mm to 0.074 mm accounting for ≥60% of the total solid particles. Activator (ammonium bicarbonate 100 g / t, copper sulfate 15 g / t), butyl xanthate (150 g / t), diesel oil (5 g / t), and sulfur frother (total 5 g / t) are added to the slurry. The ratio of No. 2 oil to No. 25 black dye is 1:3. Sulfur roughing is performed (pH 7). Then, a cleaning and two scavenging processes are performed to obtain sulfur concentrate and tailings. (Reagents are added only in the roughing stage; no reagents are added in the cleaning and scavenging stages).

[0068] The sulfur grade in the tailings was 4.07%, and the sulfur loss rate was 31.15%.

[0069] Example 2

[0070] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate, with the amount of copper sulfate being 15g / t and the amount of ammonium bicarbonate being 120g / t.

[0071] The sulfur grade in the tailings is 4.05%, and the sulfur loss rate is 30.98%.

[0072] Example 3

[0073] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate. The amount of copper sulfate is 15g / t and the amount of ammonium bicarbonate is 140g / t.

[0074] The sulfur grade in the tailings is 3.93%, and the sulfur loss rate is 30.19%.

[0075] Example 4

[0076] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate. The amount of copper sulfate is 15g / t and the amount of ammonium bicarbonate is 150g / t.

[0077] The sulfur grade in the tailings is 3.28%, and the sulfur loss rate is 24.75%.

[0078] Example 5

[0079] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate. The amount of copper sulfate is 15g / t and the amount of ammonium bicarbonate is 160g / t.

[0080] The sulfur grade in the tailings is 3.32%, and the sulfur loss rate is 25.08%.

[0081] Example 6

[0082] This embodiment is carried out in a similar manner to that of Embodiment 4. The difference is that in step (5), the total amount of activator is kept constant, and the amount of copper sulfate is adjusted to 11 g / t and the amount of ammonium bicarbonate is adjusted to 154 g / t.

[0083] The sulfur grade in the tailings was 3.61%, and the sulfur loss rate was 27.49%.

[0084] Example 7

[0085] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is a mixture of copper sulfate and ammonium bicarbonate with an amount of 150g / t of ammonium bicarbonate and 10g / t of copper sulfate.

[0086] The sulfur grade in the tailings is 3.98%, and the sulfur loss rate is 30.62%.

[0087] Example 8

[0088] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate, with the amount of ammonium bicarbonate being 150g / t and the amount of copper sulfate being 12g / t.

[0089] The sulfur grade in the tailings is 3.54%, and the sulfur loss rate is 26.91%.

[0090] Example 9

[0091] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate, with the amount of ammonium bicarbonate being 150g / t and the amount of copper sulfate being 20g / t.

[0092] The sulfur grade in the tailings is 3.50%, and the sulfur loss rate is 26.57%.

[0093] Example 10

[0094] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 100g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate. The amount of ammonium bicarbonate is 150g / t, and the amount of copper sulfate is 15g / t.

[0095] The sulfur grade in the tailings is 3.79%, and the sulfur loss rate is 29.01%.

[0096] Example 11

[0097] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 110 g / t, the amount of diesel is 5 g / t, the total amount of sulfur foaming agent is 5 g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate. The amount of ammonium bicarbonate is 150 g / t, and the amount of copper sulfate is 15 g / t.

[0098] The sulfur grade in the tailings is 3.71%, and the sulfur loss rate is 28.33%.

[0099] Example 12

[0100] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 120g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate, with the amount of ammonium bicarbonate being 150g / t and the amount of copper sulfate being 15g / t.

[0101] The sulfur grade in the tailings is 3.67%, and the sulfur loss rate is 27.99%.

[0102] Example 13

[0103] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 130g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is made by mixing copper sulfate and ammonium bicarbonate, with the amount of ammonium bicarbonate being 150g / t and the amount of copper sulfate being 15g / t.

[0104] The sulfur grade in the tailings is 3.52%, and the sulfur loss rate is 26.74%.

[0105] Example 14

[0106] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 140 g / t, the amount of diesel is 5 g / t, the total amount of sulfur foaming agent is 5 g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is a mixture of copper sulfate and ammonium bicarbonate, with the amount of ammonium bicarbonate being 150 g / t and the amount of copper sulfate being 15 g / t.

[0107] The sulfur grade in the tailings is 3.50%, and the sulfur loss rate is 26.57%.

[0108] Example 15

[0109] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the activator is copper sulfate and ammonium bicarbonate in a ratio of 150g / t, the amount of ammonium bicarbonate is 15g / t, the amount of copper sulfate is 15g / t, the total amount of sulfur foaming agent is 5g / t, and the ratio of No. 2 oil to No. 25 black powder is 1:1.

[0110] The sulfur grade in the tailings is 3.89%, and the sulfur loss rate is 29.85%.

[0111] Example 16

[0112] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the activator is copper sulfate and ammonium bicarbonate in a ratio of 150g / t, the amount of ammonium bicarbonate is 15g / t, the amount of copper sulfate is 15g / t, the total amount of sulfur foaming agent is 5g / t, and the ratio of No. 2 oil to No. 25 black powder is 1:2.

[0113] The sulfur grade in the tailings is 3.70%, and the sulfur loss rate is 29.85%.

[0114] Example 17

[0115] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the activator is copper sulfate and ammonium bicarbonate in a ratio of 150g / t, the amount of ammonium bicarbonate is 15g / t, the amount of copper sulfate is 15g / t, the total amount of sulfur foaming agent is 5g / t, and the ratio of No. 2 oil to No. 25 black powder is 1:4.

[0116] The sulfur grade in the tailings is 2.45%, and the sulfur loss rate is 17.86%.

[0117] Example 18

[0118] This embodiment is carried out in a similar manner to that of Embodiment 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the activator is copper sulfate and ammonium bicarbonate in a ratio of 150g / t, the amount of ammonium bicarbonate is 15g / t, the amount of copper sulfate is 15g / t, the total amount of sulfur foaming agent is 5g / t, and the ratio of No. 2 oil to No. 25 black powder is 1:5.

[0119] The sulfur grade in the tailings is 1.69%, and the sulfur loss rate is 12.06%.

[0120] Example 19

[0121] The raw ore is the same as in Example 18.

[0122] Step (1): The sulfur-containing copper-zinc ore is slurry-treated and ground to obtain a fine grinding slurry; the -0.074mm particles in the fine grinding slurry account for 50% of the total solid particles.

[0123] Steps (2), (3), (4) and (5) are the same as in Example 18.

[0124] The sulfur grade in the tailings is 3.70%, and the sulfur loss rate is 28.25%.

[0125] Example 20

[0126] This embodiment is carried out in a similar manner to that of embodiment 4. The difference is that in step (5), the activator is made by mixing copper sulfate and ammonium bicarbonate, maintaining the mass ratio of ammonium bicarbonate to copper sulfate at 1:10, and adjusting the total amount of activator to 200g / t.

[0127] The sulfur grade in the tailings is 3.89%, and the sulfur loss rate is 29.85%.

[0128] Example 21

[0129] Steps (1) to (4) are the same as in Example 18;

[0130] Step (5): The zinc flotation tailings are classified by particle size to obtain a flotation slurry with particles ranging from 0.037mm to 0.074mm accounting for 50% of the total solid particles. Butyl xanthate (150g / t), diesel oil (5g / t), activator (copper sulfate and ammonium bicarbonate mixed in a ratio of 150g / t and 15g / t of copper sulfate), and sulfur frother (5g / t) are added to the slurry. The ratio of No. 2 oil to No. 25 black reagent is 1:5. Sulfur flotation is then performed (pH 7) to obtain sulfur concentrate and tailings. Activator, collector, and frother are added only in the roughing stage; no reagents are added in the cleaning and scavenging stages.

[0131] The sulfur grade in the tailings was 2.94%, and the sulfur loss rate was 21.73%.

[0132] Example 22

[0133] This embodiment is carried out in a similar manner to that of embodiment 21, except that in step (5), the sulfur foaming agent is 5g / t of No. 2 oil and No. 25 black powder is added.

[0134] The sulfur grade in the tailings is 3.23%, and the sulfur loss rate is 24.34%.

[0135] Comparative Example 1

[0136] This comparative example is carried out using a method similar to that of Example 1. The difference is that in step (5), the amount of butyl xanthate is 150 g / t, the amount of diesel is 5 g / t, the total amount of sulfur foaming agent is 5 g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is ammonium bicarbonate with an amount of 100 g / t.

[0137] The sulfur grade in the tailings was 5.33%, and the sulfur loss rate was 41.80%.

[0138] Comparative Example 2

[0139] This comparative example is carried out in a similar manner to Example 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is ammonium bicarbonate with an amount of 150g / t.

[0140] The sulfur grade in the tailings was 5.14%, and the sulfur loss rate was 40.07%.

[0141] Comparative Example 3

[0142] This comparative example is carried out in a similar manner to Example 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is ammonium bicarbonate with an amount of 180g / t.

[0143] The sulfur grade in the tailings is 4.88%, and the sulfur loss rate is 38.25%.

[0144] Comparative Example 4

[0145] This comparative example is carried out in a similar manner to Example 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is ammonium bicarbonate with an amount of 200g / t.

[0146] The sulfur grade in the tailings was 4.81%, and the sulfur loss rate was 37.62%.

[0147] Comparative Example 5

[0148] This comparative example is carried out in a similar manner to Example 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is ammonium bicarbonate with an amount of 250g / t.

[0149] The sulfur grade in the tailings is 5.03%, and the sulfur loss rate is 39.07%.

[0150] Comparative Example 6

[0151] This comparative example is carried out in a similar manner to Example 1. The difference is that in step (5), the amount of butyl xanthate is 150g / t, the amount of diesel is 5g / t, the total amount of sulfur foaming agent is 5g / t, the ratio of No. 2 oil to No. 25 black powder is 1:3, and the activator is ammonium bicarbonate with an amount of 300g / t.

[0152] The sulfur grade in the tailings was 5.13%, and the sulfur loss rate was 39.98%.

[0153] Comparative Example 7

[0154] This comparative example is carried out using a method similar to that of Example 1. The difference is that in step (5), the amount of butyl xanthate is 150 g / t, the amount of diesel is 5 g / t, the total amount of sulfur foaming agent is 5 g / t, the ratio of No. 2 oil to No. 25 black powder is 1:5, and the activator is ammonium bicarbonate, with an amount of ammonium bicarbonate of 165 g / t.

[0155] The sulfur grade in the tailings is 5.03%, and the sulfur loss rate is 39.07%.

[0156] Comparative Example 8

[0157] This comparative example was carried out using a method similar to that of Example 4. The difference is that in step (5), the total amount of activator was kept constant, and the amount of copper sulfate was adjusted to 102 g / t and the amount of ammonium bicarbonate was adjusted to 63 g / t.

[0158] The sulfur grade in the tailings was 4.99%, and the sulfur loss rate was 38.71%.

[0159] Comparative Example 10

[0160] This comparative example was carried out using a method similar to that of Example 21, except that no foam modifier was added in step (5).

[0161] The sulfur grade in the tailings was 4.98%, and the sulfur loss rate was 38.62%.

[0162] The results from the examples above demonstrate that the flotation method of this invention produces abundant flotation froth of uniform size that is not easily broken, while also carrying a large amount of the target mineral. Furthermore, in the flotation of pyrite, the activator is more effective and requires a lower dosage when used in combination with other activators compared to using them alone, effectively reducing pyrite loss in tailings and achieving efficient recovery of pyrite.

[0163] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A flotation method for sulfur-containing copper-zinc ore, characterized in that: The method includes: (1) The sulfur-containing copper-zinc ore is subjected to slurry preparation and grinding to obtain fine grinding slurry; (2) The finely ground slurry is mixed with flotation reagents including copper collectors to carry out copper flotation, thereby obtaining copper concentrate and copper flotation tailings; (3) The copper flotation tailings are subjected to wet magnetic separation to obtain pyrrhotite concentrate and magnetic separation tailings; (4) The magnetic separation tailings are mixed with flotation reagents including zinc activator, zinc collector, zinc frother and lime inhibitor to carry out zinc flotation to obtain zinc concentrate and zinc flotation tailings; (5) The zinc flotation tailings are subjected to particle size classification or secondary grinding to obtain a slurry to be flotated; the slurry to be flotated is mixed with flotation reagents including sulfur activator, sulfur collector, froth modifier and sulfur frother to carry out sulfur flotation to obtain sulfur concentrate and tailings; the sulfur activator is a combination of ammonium bicarbonate and copper sulfate with a mass ratio of 5~20:1, the amount of sulfur activator is 110~220g / t, the sulfur collector is butyl xanthate, and the froth modifier is diesel oil.

2. The flotation method for sulfur-bearing copper-zinc ore according to claim 1, characterized in that: The concentration of the finely ground slurry is 35-40 wt%; And / or, particles of -0.074 mm in the finely ground slurry account for ≥55% of the total solid particles by mass; And / or, the sulfur content in the sulfur-bearing copper-zinc ore is 10-17 wt%.

3. The flotation method for sulfur-bearing copper-zinc ore according to claim 1 or 2, characterized in that: The copper collector is selected from at least one of butylammonium black powder, 25# black powder, and ethyl thiocyanate.

4. A flotation method for sulfur-bearing copper-zinc ore according to claim 1 or 2, characterized in that: The magnetic field strength of the wet magnetic separator is 0.1~0.2T.

5. A flotation method for sulfur-bearing copper-zinc ore according to claim 1 or 2, characterized in that: The zinc activator is copper sulfate and / or lead nitrate; the zinc collector is ethyl thiocyanate and / or butyl xanthate; the zinc foaming agent is 25# black powder and / or 2# oil.

6. A flotation method for sulfur-bearing copper-zinc ore according to claim 1 or 2, characterized in that: The sulfur foaming agent is 25# black powder and / or 2# oil; And / or, the sulfur activator is a composition of ammonium bicarbonate and copper sulfate in a mass ratio of 6 to 15:

1.

7. A flotation method for sulfur-bearing copper-zinc ore according to claim 1 or 2, characterized in that: In the slurry to be flotated, particles with a size range of 0.037 mm to 0.074 mm account for ≥60% of the total solid particle mass.

8. A flotation method for sulfur-bearing copper-zinc ore according to claim 1 or 2, characterized in that: The pH value for copper flotation is 6-7, and the amount of copper collector used is 1-5 g / t.

9. A flotation method for sulfur-bearing copper-zinc ore according to claim 1 or 2, characterized in that: The pH value of the zinc flotation is 7-8, the amount of zinc activator is 100-200 g / t, the amount of zinc collector is 1-5 g / t, the total amount of zinc frother is 1-5 g / t, and the amount of lime is 800-1000 g / t. Preferably, the pH value of the zinc flotation is 7~7.5, the amount of zinc activator is 100~150g / t, the amount of zinc collector is 2~5g / t, the total amount of zinc frother is 1~5g / t, and the amount of lime is 900~1000g / t.

10. A flotation method for sulfur-bearing copper-zinc ore according to claim 1 or 2, characterized in that: The pH value of the sulfur flotation is 7-8, the total amount of sulfur frother is 1-5 g / t, the amount of sulfur collector is 20-300 g / t, and the amount of foam modifier is 1-5 g / t. Preferably, the pH value of the sulfur flotation is 6.5-7, the amount of sulfur activator is 140-170 g / t, the total amount of sulfur frother is 2-5 g / t, the amount of sulfur collector is 100-150 g / t, and the amount of foam modifier is 3-5 g / t. More preferably, the total amount of sulfur foaming agent is 3~5 g / t, the amount of sulfur collector is 130~150 g / t, and the amount of foam modifier is 3~5 g / t; More preferably, the sulfur flotation separation adopts a flotation process of one roughing and one cleaning.

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