A method for high-grade zinc concentrate separation by high-sulfur lead-zinc ore flow separation and speed flotation

Abstract

The present application relates to a kind of high-sulfur lead-zinc ore split flow and speed flotation high-grade zinc concentrate method, the method uses sodium carbonate, humic acid salt, yeast powder, sodium sulfide, sodium pyrosulfite One or several combinations of sulfur depressant Ts4, zinc collector LY consisting of N, N-dialkyl dithiocarbamic acid ester, hydrocarbyl dithiophosphoric acid sulfide ester, octanol and non-polar oil portion, the method of split flow and speed flotation is carried out for zinc dressing, in the presence of high sulfur, can not add lime or strong base, it is conducive to environmental protection requirement, while can reduce reagent dosage, save reagent cost, reduce zinc concentrate amount, reduce equipment use and maintenance cost, while being able to obtain high-quality high recovery rate zinc concentrate, reach the final goal of efficient recovery of zinc mineral.

Description

Technical Field

[0001] This invention belongs to the field of mineral processing technology, and in particular relates to a method for fractional flotation of high-sulfur lead-zinc ore to obtain high-grade zinc concentrate, which is suitable for beneficiation applications of various lead-zinc ores. Background Technology

[0002] One of the challenges in beneficiating high-sulfur lead-zinc ores is the separation of lead and zinc from sulfur. This is mainly due to the high sulfur content in the ores, which makes sulfur suppression difficult, resulting in low separation efficiency, high intermingling of lead, zinc, and sulfur in the concentrates, low concentrate quality, and low lead and zinc recovery rates. Currently, most lead-zinc ore beneficiation processes employ a high-alkali process based on lime to separate lead, zinc, and sulfur. This involves using lime-zinc sulfate as a depressant to suppress zinc and sulfur for lead flotation, followed by activation of zinc with copper sulfate, and finally, zinc flotation using a collector primarily composed of xanthate. For example, Chinese patents such as "A Rate-Separated Flotation Process for Sphalerite" (CN202110576866.7) add lime as a sulfur inhibitor and use butyl xanthate as a collector for zinc extraction; "A Beneficiation Method for Lead-Zinc Sulfide Ores Combining Iron-Bearing Sphalerite and Pyrite" (CN202110330898.9) add lime as a sulfur inhibitor and use butyl xanthate as a collector for zinc extraction; and "A Method for Improving the Main Grade of Zinc Concentrate After Copper-Zinc Separation" (CN202110521181.2) add lime as a sulfur inhibitor and potassium dichromate, which seriously pollutes the environment, and use butyl xanthate as a collector for zinc extraction. The problems with this process are: 1) Due to the presence of high sulfur, it is difficult to obtain high-quality zinc concentrate, and the zinc recovery rate is low; 3) Zinc inhibited by high alkali requires more activators for activation, resulting in high reagent costs.

[0003] In summary, researching and developing new beneficiation processes and environmentally friendly reagents that can improve zinc quality and recovery rate is a new trend in zinc beneficiation. Summary of the Invention

[0004] The purpose of this invention is to provide a method for effectively improving the quality and recovery rate of high-sulfur lead-zinc ore by fractional flotation to obtain high-grade zinc concentrate.

[0005] The technical solution adopted to achieve the above-mentioned objectives is as follows:

[0006] A method for fractional flotation of high-sulfur lead-zinc ore to obtain high-grade zinc concentrate, characterized by the following steps:

[0007] 1) Using the tailings from the conventional lead preferential flotation process as feed, add 50-1000 g / t of activator CuSO4 and 5-50 g / t of collector LY, stir and then carry out zinc rough I flotation to obtain zinc concentrate I and zinc rough I tailings;

[0008] 2) Add 200-1000 g / t sulfur inhibitor T to the above-mentioned zinc crude tailings. s4Mix with 30-200 g / t collector LY, stir, and then carry out zinc rough II flotation to obtain zinc rough II concentrate and zinc rough II tailings;

[0009] 3) Add 10-50 g / t sulfur inhibitor T to the above-mentioned zinc crude II concentrate. s4 After 1 to 4 rounds of fine selection, zinc concentrate II is obtained. The tailings from each zinc fine selection are returned to the previous operation in sequence. Combining zinc concentrate I and zinc concentrate II yields high-grade zinc concentrate.

[0010] 4) Add 10-50 g / t collector LY to the above-mentioned zinc rough II tailings and perform 1-4 scavenging processes to obtain zinc tailings. The zinc scavenging concentrates of each grade are returned to the previous operation in sequence.

[0011] The sulfur inhibitor T s4 It is one or more of sodium carbonate, humate, yeast powder, sodium sulfide, and sodium metabisulfite, wherein the mass percentage of sodium carbonate, humate, yeast powder, sodium sulfide, and sodium metabisulfite is 30:10:5:20:35.

[0012] The zinc collector LY is composed of 60-80 parts of N,N-dialkyldithiocarbamate, 10-30 parts of alkyl dithiophosphate thioether ester, 3-5 parts of octanol, and 5-10 parts of non-polar oil. The method is as follows: N,N-dialkyldithiocarbamate and alkyl dithiophosphate thioether ester are mixed evenly, octanol and non-polar oil are added, and the mixture is stirred at 300 r / min for 0.5 h to obtain the zinc collector (LY).

[0013] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention employs a split-flow, split-rate flotation method for zinc beneficiation. The key to this technology is the absence of strong alkalis such as lime, which helps maintain the natural floatability of zinc minerals. A novel, highly efficient, and selective zinc collector, LY, is selected. Utilizing the natural floatability of zinc minerals and the residual reagents in the reflux water, a small amount of collector is added to perform zinc roughing (I) on the slurry. High-quality zinc concentrate (I) can be directly obtained directly without further refining. Under natural pH conditions, a novel inhibitor, T, is used. s4 It has a strong selective inhibition effect on sulfur, so it can effectively separate zinc and sulfur under high sulfur conditions to obtain zinc concentrate II. Combining zinc concentrate I and zinc concentrate II yields high-grade zinc concentrate.

[0014] The fractional flotation method of the present invention can eliminate the need to add lime or strong alkali in the presence of high sulfur, which is beneficial to environmental protection requirements. At the same time, it can reduce the amount of reagents used, save reagent costs, reduce the amount of zinc concentrate, and reduce equipment use and maintenance costs.

[0015] The fractional flotation method of the present invention can obtain high-quality zinc concentrate with high recovery rate, achieving the ultimate goal of efficient recovery of zinc minerals, and is a new trend and direction for the development of zinc beneficiation.

[0016] Instruction manual illustrations

[0017] Figure 1 This is a process flow diagram of the present invention;

[0018] Figure 2 This is a flowchart of the existing technology process. Detailed Implementation

[0019] This invention relates to a method for fractional flotation of high-sulfur lead-zinc ore to obtain high-quality zinc concentrate. This method is applicable to lead-zinc ores with various sulfur contents, and the feed typically consists of lead flotation tailings. The key to this technology lies in avoiding the addition of strong alkalis such as lime, which helps maintain the natural floatability of zinc minerals. A novel, highly efficient, and selective zinc collector, LY, is selected. Utilizing the natural floatability of zinc minerals and the remaining reagents in the reflux water, a small amount of collector is added for zinc roughing (I) flotation of the pulp. High-quality zinc concentrate (I) can be directly obtained without further refining. Under natural pH conditions, a novel inhibitor, T, is used. s4 It has a strong selective inhibition effect on sulfur, so it can effectively separate zinc and sulfur under high sulfur conditions to obtain zinc concentrate II. Combining zinc concentrate I and zinc concentrate II yields high-grade zinc concentrate.

[0020] The above-mentioned sulfur inhibitor T s4 The mass percentages of sodium carbonate, humate, yeast powder, sodium sulfide, and sodium metabisulfite, calculated by weight, are 30:10:5:20:35.

[0021] The zinc collector LY is composed of 60-80 parts of N,N-dialkyldithiocarbamate, 10-30 parts of alkyl dithiophosphate thioether ester, 3-5 parts of octanol, and 5-10 parts of non-polar oil. The method is as follows: N,N-dialkyldithiocarbamate and alkyl dithiophosphate thioether ester are mixed evenly, octanol and non-polar oil are added, and the mixture is stirred at 300 r / min for 0.5 h to obtain the zinc collector (LY).

[0022] The following are some examples of zinc collector LY for further illustration.

[0023] Example 1 of zinc collector LY: 60 parts of N,N-dialkyl dithiocarbamate, 12 parts of hydrocarbon dithiophosphate thioether ester, 3 parts of octanol, and 6 parts of nonpolar oil.

[0024] Example 2 of zinc collector LY: 75 parts of N,N-dialkyl dithiocarbamate, 25 parts of hydrocarbon dithiophosphate thioether ester, 4 parts of octanol, and 7 parts of nonpolar oil.

[0025] Example 3 of zinc collector LY: 78 parts of N,N-dialkyl dithiocarbamate, 19 parts of hydrocarbon dithiophosphate thioether ester, 5 parts of octanol, and 6 parts of nonpolar oil.

[0026] Example 4 of zinc collector LY: 65 parts of N,N-dialkyl dithiocarbamate, 10 parts of hydrocarbon dithiophosphate thioether ester, 3 parts of octanol, and 5 parts of nonpolar oil.

[0027] The technical solution of the present invention will be described in detail below through specific embodiments, but this does not limit the scope of the present invention. The embodiments described below are only some embodiments of the present invention, not all embodiments. All other similar embodiments made by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] In the following examples, unless otherwise specified, all reagents used are commercially available products. Specific experimental procedures or conditions were performed according to the conventional experimental procedures and conditions described in the literature in this field. All concentrations or contents in the examples are mass percentages.

[0029] The process flow of the example is shown below. Figure 1 ,according to Figure 1 The implementation steps demonstrated involve zinc fractionation flotation of lead scavenging tailings (feed). The comparative example and the embodiment have the same ore properties and use butyl xanthate, the most commonly used collector in existing zinc flotation technology. The results of the comparative example and the embodiment are shown in Table 1.

[0030] Example 1

[0031] The raw ore of a lead-zinc mine in Yunnan Province contains 5.56% Pb, 16.72% Zn, and 30.21% S, which are high-sulfur lead-zinc deposits. The main useful minerals are galena, sphalerite, and pyrite, while the gangue minerals are mainly dolomite and calcite. The zinc concentrate obtained from the lead tailings using conventional flotation processes has a grade of approximately 52%, making it difficult to obtain high-quality zinc concentrate. The tailings after preferential lead flotation are then subjected to zinc fractionation at different rates using the following steps:

[0032] (1) The raw ore was ground to obtain a slurry with a grinding fineness of -0.074 mm particles accounting for 75%. The obtained slurry was added to a flotation machine for lead-preferred flotation. The lead-preferred flotation consisted of one roughing, three scavenging, and three cleaning processes to obtain lead concentrate and lead scavenging tailings. The yield of lead scavenging tailings was about 92% of that of the raw ore.

[0033] (2) The lead scavenging tailings obtained in step (1) are subjected to zinc preferential flotation. After adding 500g / t activator CuSO4 and 30g / t collector LY and stirring, zinc rough I flotation is carried out to obtain zinc concentrate I and zinc rough I tailings.

[0034] (3) Add 600g / t sulfur inhibitor T to the zinc crude tailings obtained in step (2). s4Mix with 100g / t collector LY, stir, and then carry out zinc rough II flotation to obtain zinc rough II concentrate and zinc rough II tailings.

[0035] (4) Add 30g / t sulfur inhibitor T to the zinc crude II concentrate obtained in step (3). s4 Zinc concentrate I was produced, yielding zinc concentrate I and tailings I; the obtained zinc concentrate I was then treated with 15 g / t sulfur inhibitor T. s4 Zinc concentrate II was produced, yielding zinc concentrate II ore and concentrate II tailings; the obtained zinc concentrate II ore was then treated with 10 g / t sulfur inhibitor T. s4 Zinc concentrate III is processed, yielding zinc concentrate II and zinc concentrate III tailings. Zinc concentrate I and zinc concentrate II are then combined to form a single zinc concentrate. The tailings from each zinc concentrate stage are sequentially returned to the previous operation.

[0036] (5) Add 45g / t collector LY to the zinc rough II tailings obtained in step (3) for zinc scavenging I to obtain zinc scavenging I concentrate and zinc scavenging I tailings; add 30g / t collector LY to the obtained zinc scavenging I tailings for zinc scavenging II to obtain zinc scavenging II concentrate and zinc scavenging II tailings; add 20g / t collector LY to the obtained zinc scavenging II tailings for zinc scavenging III to obtain zinc scavenging III concentrate and zinc tailings, and return the zinc scavenging concentrates of each level to the previous operation in sequence.

[0037] Comparative Example 1

[0038] The raw ore, grinding, and lead flotation processes are the same as in Example 1. The zinc flotation process for Comparative Example 1 is shown below. Figure 2 Follow these steps:

[0039] (1) The raw ore was ground to obtain a slurry with a grinding fineness of -0.074 mm particles accounting for 75%. The obtained slurry was added to a flotation machine for lead-preferred flotation. The lead-preferred flotation consisted of one roughing, three scavenging, and three cleaning processes to obtain lead concentrate and lead scavenging tailings. The yield of lead scavenging tailings was about 92% of that of the raw ore.

[0040] (2) The lead scavenging tailings obtained in step (1) are subjected to zinc preferential flotation. 2000g / t sulfur inhibitor lime, 500g / t activator CuSO4 and 130g / t collector butyl xanthate are added and stirred before zinc roughing is carried out to obtain zinc roughing concentrate and zinc roughing tailings.

[0041] (3) Add 500g / t of sulfur inhibitor lime to the zinc crude concentrate obtained in step (2) to perform zinc refining I, and obtain zinc concentrate I concentrate and zinc concentrate I tailings; add 300g / t of sulfur inhibitor lime to the obtained zinc concentrate I to perform zinc refining II, and obtain zinc concentrate II concentrate and zinc concentrate II tailings; add 200g / t of sulfur inhibitor lime to the obtained zinc refining II concentrate to perform zinc refining III, and obtain zinc concentrate and zinc concentrate III tailings. The zinc refining tailings of each level are returned to the previous operation in sequence.

[0042] (4) Add 45g / t of collector butyl xanthate to the zinc roughing tailings from step (2) for zinc scavenging I to obtain zinc scavenging I concentrate and zinc scavenging I tailings; add 30g / t of collector butyl xanthate to the zinc scavenging I tailings for zinc scavenging II to obtain zinc scavenging II concentrate and zinc scavenging II tailings; add 20g / t of collector butyl xanthate to the zinc scavenging II tailings for zinc scavenging III to obtain zinc scavenging III concentrate and zinc scavenging III tailings; add 10g / t of collector butyl xanthate to the zinc scavenging III tailings for zinc scavenging IV to obtain zinc scavenging IV concentrate and zinc tailings. The zinc scavenging concentrates from each stage are returned to the previous operation in sequence.

[0043] Example 2

[0044] The raw ore of a lead-zinc mine in Yunnan Province contains 6.77% Pb, 20.16% Zn, and 28.67% S, respectively. It is a high-sulfur lead-zinc ore, with the main useful minerals being galena, sphalerite, and pyrite. The gangue minerals are mainly dolomite, calcite, and muscovite. The zinc concentrate obtained from the lead tailings using conventional flotation has a grade of approximately 52%. The tailings after preferential lead flotation are then subjected to zinc fractionation at different rates using the following steps:

[0045] (1) The raw ore was ground to obtain a slurry with a grinding fineness of -0.074 mm particles accounting for 73%. The obtained slurry was added to a flotation machine for lead-preferred flotation. The lead-preferred flotation consisted of one roughing, three scavenging, and three cleaning processes to obtain lead concentrate and lead scavenging tailings. The yield of lead scavenging tailings was about 90% of that of the raw ore.

[0046] (2) The lead scavenging tailings obtained in step (1) are subjected to zinc preferential flotation. 600g / t activator CuSO4 and 45g / t collector LY are added and stirred before zinc rough I flotation is carried out to obtain zinc concentrate I and zinc rough I tailings.

[0047] (3) Add 500g / t sulfur inhibitor T to the zinc crude tailings obtained in step (2). s4 Mix with 120g / t collector LY, stir, and then carry out zinc rough II flotation to obtain zinc rough II concentrate and zinc rough II tailings.

[0048] (4) Add 25g / t sulfur inhibitor T to the zinc crude II concentrate obtained in step (3). s4 Zinc concentrate I was processed to obtain zinc concentrate I and concentrate I tailings; the obtained zinc concentrate I was treated with 15 g / t sulfur inhibitor T. s4 Zinc concentrate II was produced, yielding zinc concentrate II ore and concentrate II tailings; the obtained zinc concentrate II ore was then treated with 10 g / t sulfur inhibitor T. s4 Zinc concentrate III is processed, yielding zinc concentrate II and zinc concentrate III tailings. Zinc concentrate I and zinc concentrate II are then combined to form zinc concentrate. The zinc concentrate tailings from each stage are returned sequentially to the previous operation.

[0049] (5) Add 50g / t collector LY to the zinc rough II tailings obtained in step (3) for zinc scavenging I to obtain zinc scavenging I concentrate and zinc scavenging I tailings; add 25g / t collector LY to the obtained zinc scavenging I tailings for zinc scavenging II to obtain zinc scavenging II concentrate and zinc scavenging II tailings; add 20g / t collector LY to the obtained zinc scavenging II tailings for zinc scavenging III to obtain zinc scavenging III concentrate and zinc tailings, and return the zinc scavenging concentrates of each level to the previous operation in sequence.

[0050] Comparative Example 2

[0051] The raw ore, grinding, and lead flotation processes are the same as in Example 2. The zinc flotation process for Comparative Example 2 is shown below. Figure 2 Follow these steps:

[0052] (1) The raw ore was ground to obtain a slurry with a grinding fineness of -0.074 mm particles accounting for 73%. The obtained slurry was added to a flotation machine for lead-preferred flotation. The lead-preferred flotation consisted of one roughing, three scavenging, and three cleaning processes to obtain lead concentrate and lead scavenging tailings. The yield of lead scavenging tailings was about 90% of that of the raw ore.

[0053] (2) The lead scavenging tailings obtained in step (1) are subjected to zinc preferential flotation. 2500g / t sulfur inhibitor lime, 600g / t activator CuSO4 and 165g / t collector butyl xanthate are added and stirred before zinc roughing is carried out to obtain zinc roughing concentrate and zinc roughing tailings.

[0054] (3) Add 800g / t of sulfur inhibitor lime to the zinc crude concentrate obtained in step (2) to perform zinc refining I, and obtain zinc concentrate I concentrate and zinc concentrate I tailings; add 400g / t of sulfur inhibitor lime to the obtained zinc concentrate I to perform zinc refining II, and obtain zinc concentrate II concentrate and zinc concentrate II tailings; add 200g / t of sulfur inhibitor lime to the obtained zinc refining II concentrate to perform zinc refining III, and obtain zinc concentrate and zinc concentrate III tailings. The zinc refining tailings of each level are returned to the previous operation in sequence.

[0055] (4) Add 50g / t of collector butyl xanthate to the zinc roughing tailings from step (2) for zinc scavenging I to obtain zinc scavenging I concentrate and zinc scavenging I tailings; add 25g / t of collector butyl xanthate to the zinc scavenging I tailings for zinc scavenging II to obtain zinc scavenging II concentrate and zinc scavenging II tailings; add 20g / t of collector butyl xanthate to the zinc scavenging II tailings for zinc scavenging III to obtain zinc scavenging III concentrate and zinc scavenging III tailings; add 10g / t of collector butyl xanthate to the zinc scavenging III tailings for zinc scavenging IV to obtain zinc scavenging IV concentrate and zinc tailings. The zinc scavenging concentrates of each stage are returned to the previous operation in sequence.

[0056] Example 3

[0057] A lead-zinc mine in Inner Mongolia has Pb, Zn, and S contents of 3.25%, 2.95%, and 26.25%, respectively. It is a high-sulfur lead-zinc mine, with the main useful minerals being galena, sphalerite, and pyrite. Gangue minerals are primarily quartz, muscovite, and kaolinite. The zinc concentrate obtained from the lead tailings using conventional flotation has a grade of approximately 51%. The tailings after preferential lead flotation are then subjected to zinc fractionation at different rates using the following steps:

[0058] (1) The raw ore was ground to obtain a slurry with a grinding fineness of -0.074 mm particles accounting for 70%. The obtained slurry was fed into a flotation machine for lead-preferred flotation. The lead-preferred flotation consisted of one roughing, three scavenging, and three cleaning processes to obtain lead concentrate and lead scavenging tailings. The yield of lead scavenging tailings was about 95% of that of the raw ore.

[0059] (2) The lead scavenging tailings obtained in step (1) are subjected to zinc preferential flotation. 300g / t activator CuSO4 and 10g / t collector LY are added and stirred before zinc rough I flotation is carried out to obtain zinc concentrate I and zinc rough I tailings.

[0060] (3) Add 600g / t sulfur inhibitor T to the zinc crude tailings obtained in step (2). s4 Mix with 50g / t collector LY, stir, and then carry out zinc rough II flotation to obtain zinc rough II concentrate and zinc rough II tailings.

[0061] (4) Add 20g / t sulfur inhibitor T to the zinc crude II concentrate obtained in step (3). s4 Zinc concentrate I was processed to obtain zinc concentrate I and concentrate I tailings; the obtained zinc concentrate I was treated with 15 g / t sulfur inhibitor T. s4 Zinc concentrate II was produced, yielding zinc concentrate II ore and concentrate II tailings; the obtained zinc concentrate II ore was then treated with 10 g / t sulfur inhibitor T. s4 Zinc concentrate III is processed, yielding zinc concentrate II and zinc concentrate III tailings. Zinc concentrate I and zinc concentrate II are then combined to form zinc concentrate. The zinc concentrate tailings from each stage are returned sequentially to the previous operation.

[0062] (5) Add 20g / t collector LY to the zinc rough II tailings obtained in step (3) for zinc scavenging I to obtain zinc scavenging I concentrate and zinc scavenging I tailings; add 10g / t collector LY to the obtained zinc scavenging I tailings for zinc scavenging II to obtain zinc scavenging II concentrate and zinc scavenging II tailings; add 5g / t collector LY to the obtained zinc scavenging II tailings for zinc scavenging III to obtain zinc scavenging III concentrate and zinc tailings, and return the zinc scavenging concentrates of each level to the previous operation in sequence.

[0063] Comparative Example 3

[0064] The raw ore, grinding, and lead flotation processes are the same as in Example 3. The zinc flotation process for Comparative Example 3 is shown below. Figure 2 Follow these steps:

[0065] (1) The raw ore was ground to obtain a slurry with a grinding fineness of -0.074 mm particles accounting for 70%. The obtained slurry was fed into a flotation machine for lead-preferred flotation. The lead-preferred flotation consisted of one roughing, three scavenging, and three cleaning processes to obtain lead concentrate and lead scavenging tailings. The yield of lead scavenging tailings was about 95% of that of the raw ore.

[0066] (2) The lead scavenging tailings obtained in step (1) are subjected to zinc preferential flotation. 1500g / t sulfur inhibitor lime, 300g / t activator CuSO4 and 60g / t collector butyl xanthate are added and stirred before zinc roughing is carried out to obtain zinc roughing concentrate and zinc roughing tailings.

[0067] (3) Add 300g / t of sulfur inhibitor lime to the zinc crude concentrate obtained in step (2) to produce zinc concentrate I, and obtain zinc concentrate I concentrate and zinc concentrate I tailings; add 200g / t of sulfur inhibitor lime to the zinc concentrate I to produce zinc concentrate II, and obtain zinc concentrate II concentrate and zinc concentrate II tailings; add 100g / t of sulfur inhibitor lime to the zinc concentrate II to produce zinc concentrate III, and obtain zinc concentrate and zinc concentrate III tailings. The zinc concentrate tailings of each grade are returned to the previous operation in sequence.

[0068] (4) Add 20g / t of collector butyl xanthate to the zinc roughing tailings from step (2) for zinc scavenging I to obtain zinc scavenging I concentrate and zinc scavenging I tailings; add 10g / t of collector butyl xanthate to the zinc scavenging I tailings for zinc scavenging II to obtain zinc scavenging II concentrate and zinc scavenging II tailings; add 5g / t of collector butyl xanthate to the zinc scavenging II tailings for zinc scavenging III to obtain zinc scavenging III concentrate and zinc scavenging III tailings; add 5g / t of collector butyl xanthate to the zinc scavenging III tailings for zinc scavenging IV to obtain zinc scavenging IV concentrate and zinc tailings. The zinc scavenging concentrates of each stage are returned to the previous operation in sequence.

[0069] Example 4

[0070] A lead-zinc mine in Guangxi has Pb, Zn, and S contents of 0.71%, 2.56%, and 8.25%, respectively. The main useful minerals are galena, sphalerite, and pyrite, while the gangue minerals are primarily barite, dolomite, quartz, and mica. The zinc concentrate obtained from the lead tailings using conventional flotation has a grade of approximately 50%. The tailings after preferential lead flotation are then subjected to zinc fractionation at different rates using the following steps:

[0071] (1) The raw ore was ground to obtain a slurry with a grinding fineness of -0.074 mm particles accounting for 80%. The obtained slurry was fed into a flotation machine for lead-preferred flotation. The lead-preferred flotation consisted of one roughing, three scavenging, and three cleaning processes to obtain lead-sulfur inhibitor T. s4 Concentrate and lead scavenging tailings. The yield of lead scavenging tailings is about 98% of that of the original ore.

[0072] (2) The lead scavenging tailings obtained in step (1) are subjected to zinc preferential flotation. After adding 300g / t activator CuSO4 and 5g / t collector LY and stirring, zinc rough I flotation is carried out to obtain zinc concentrate I and zinc rough I tailings.

[0073] (3) Add 300g / t sulfur inhibitor T to the zinc crude tailings obtained in step (2). s4 Mix with 45g / t collector LY, stir, and then carry out zinc rough II flotation to obtain zinc rough II concentrate and zinc rough II tailings.

[0074] (4) Add 20g / t sulfur inhibitor T to the zinc crude II concentrate obtained in step (3). s4 Zinc concentrate I was processed to obtain zinc concentrate I and concentrate I tailings; the obtained zinc concentrate I was treated with 10 g / t sulfur inhibitor T. s4 Zinc concentrate II was produced, yielding zinc concentrate II ore and concentrate II tailings; the obtained zinc concentrate II ore was treated with 5 g / t sulfur inhibitor T. s4 Zinc concentrate III is processed, yielding zinc concentrate II and zinc concentrate III tailings. Zinc concentrate I and zinc concentrate II are then combined to form zinc concentrate. The zinc concentrate tailings from each stage are returned sequentially to the previous operation.

[0075] (5) Add 15g / t collector LY to the zinc rough II tailings obtained in step (3) for zinc scavenging I to obtain zinc scavenging I concentrate and zinc scavenging I tailings; add 10g / t collector LY to the obtained zinc scavenging I tailings for zinc scavenging II to obtain zinc scavenging II concentrate and zinc scavenging II tailings; add 5g / t collector LY to the obtained zinc scavenging II tailings for zinc scavenging III to obtain zinc scavenging III concentrate and zinc tailings, and return the zinc scavenging concentrates of each level to the previous operation in sequence.

[0076] Comparative Example 4

[0077] The raw ore, grinding, and lead flotation processes are the same as in Example 4. The zinc flotation process for Comparative Example 4 is shown below. Figure 2 Follow these steps:

[0078] (1) The raw ore was ground to obtain a slurry with a grinding fineness of -0.074 mm particles accounting for 80%. The obtained slurry was added to a flotation machine for lead-preferred flotation. The lead-preferred flotation consisted of one roughing, three scavenging, and three cleaning processes to obtain lead concentrate and lead scavenging tailings. The yield of lead scavenging tailings was about 98% of that of the raw ore.

[0079] (2) The lead scavenging tailings obtained in step (1) are subjected to zinc preferential flotation. 1000g / t sulfur inhibitor lime, 300g / t activator CuSO4 and 50g / t collector butyl xanthate are added and stirred before zinc roughing is carried out to obtain zinc roughing concentrate and zinc roughing tailings.

[0080] (3) Add 300g / t of sulfur inhibitor lime to the zinc crude concentrate obtained in step (2) to perform zinc refining I, and obtain zinc concentrate I concentrate and zinc concentrate I tailings; add 150g / t of sulfur inhibitor lime to the obtained zinc concentrate I to perform zinc refining II, and obtain zinc concentrate II concentrate and zinc concentrate II tailings; add 100g / t of sulfur inhibitor lime to the obtained zinc refining II concentrate to perform zinc refining III, and obtain zinc concentrate and zinc concentrate III tailings. The zinc refining tailings of each level are returned to the previous operation in sequence.

[0081] (4) Add 15g / t of collector butyl xanthate to the zinc roughing tailings from step (2) for zinc scavenging I to obtain zinc scavenging I concentrate and zinc scavenging I tailings; add 10g / t of collector butyl xanthate to the zinc scavenging I tailings for zinc scavenging II to obtain zinc scavenging II concentrate and zinc scavenging II tailings; add 5g / t of collector butyl xanthate to the zinc scavenging II tailings for zinc scavenging III to obtain zinc scavenging III concentrate and zinc scavenging III tailings; add 2g / t of collector butyl xanthate to the zinc scavenging III tailings for zinc scavenging IV to obtain zinc scavenging IV concentrate and zinc tailings. The zinc scavenging concentrates of each grade are returned to the previous operation in sequence.

[0082] Table 1. Experimental Results

[0083]

[0084] As illustrated by the above embodiments, the method provided by this invention can be used without adding lime or strong alkali in the presence of high sulfur, which is beneficial to environmental protection requirements. It utilizes the natural flotation of zinc minerals and adopts a new split-flow and split-rate process to obtain high-quality zinc concentrate with high recovery rate. Using this process, for various raw ores with different Zn and S contents, compared with conventional processes, the obtained zinc concentrate has a Zn content of more than 55% and the recovery rate is more than 2% higher than that of conventional processes.

Claims

1. A method for high grade zinc concentrate production by high sulphidization lead-zinc ore split flow and split speed flotation, characterized in that It comprises the following steps: 1) using tailings of conventional lead preferential flotation process as feed ore, adding activator CuSO4 and collector LY, the amount of activator CuSO4 is 50-1000 g / t of feed ore, the amount of collector LY is 5-50 g / t of feed ore, after stirring, rough I zinc flotation is carried out, and zinc concentrate I and rough I zinc tailings are obtained; 2) adding 200-1000 g / t of sulfur inhibitor Ts4 and 30-200 g / t of collector LY to the above-mentioned rough I zinc tailings, after stirring, rough II zinc flotation is carried out, and rough II zinc concentrate and rough II zinc tailings are obtained; 3) adding 10-50 g / t of sulfur inhibitor Ts4 to the above-mentioned rough II zinc concentrate, and carrying out 1-4 times of cleaning, to obtain zinc concentrate III, and the tailings of each stage of zinc cleaning are returned to the previous operation in turn; 4) combining zinc concentrate I and zinc concentrate II to obtain high-grade zinc concentrate; 5) adding 10-50 g / t of collector LY to the above-mentioned rough II zinc tailings to carry out 1-4 times of scavenging, to obtain zinc tailings, and the concentrate of each stage of zinc scavenging is returned to the previous operation in turn; The sulfur inhibitor Ts4 is a combination of sodium carbonate, humic acid salt, yeast powder, sodium sulfide and sodium metabisulfite, wherein the mass percentage of sodium carbonate, humic acid salt, yeast powder, sodium sulfide and sodium metabisulfite is 30:10:5:20:35; The zinc collector LY is composed of 60-80 parts of N,N-dialkyl dithiocarbamic acid ester, 10-30 parts of hydrocarbyl dithiophosphoric sulfide ester, 3-5 parts of octanol and 5-10 parts of non-polar oil, and the preparation method of zinc collector LY is as follows: uniformly mix N,N-dialkyl dithiocarbamic acid ester and hydrocarbyl dithiophosphoric sulfide ester, add octanol and non-polar oil, stir at 300 r / min for 0.5 h, and zinc collector LY is obtained.

2. The method of high sulphidic lead-zinc ore split-flotation split-speed for high-grade zinc concentrate according to claim 1, characterized in that, In process 2), the zinc tailings obtained by adding collector LY to the rough II zinc tailings are subjected to 1-4 times of scavenging, to obtain zinc tailings, wherein the concentrate of each stage of zinc scavenging is returned to the previous operation in turn.

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