Beneficiation method of tin-silver symbiotic polymetallic ore and application thereof

Abstract

The invention discloses a beneficiation method for tin-silver symbiotic polymetallic ore and application of the beneficiation method, and relates to the technical field of mineral separation. Comprising the steps that after tin-silver symbiotic polymetallic ore is ground, undersize minerals are obtained through a high-frequency screen, silver-copper flotation is conducted on the undersize minerals, and silver-copper concentrate and silver-copper tailings are obtained; the silver-copper tailings are subjected to lead-zinc-sulfur flotation, and lead concentrate and zinc-sulfur tailings are obtained; and the zinc-sulfur tailings are subjected to zinc-sulfur flotation, and zinc-sulfur concentrate and tin-sulfur tailings are obtained. The concentration of ore pulp in the ore grinding process is controlled, it is guaranteed that cassiterite and sulfide minerals are fully dissociated, then a first inhibitor is added in the lead-zinc-sulfur flotation process, the valuable metal recovery efficiency can be enhanced by optimizing the flotation process and collaboratively innovating a reagent formula according to the complex characteristics of tin-silver symbiotic polymetallic ore, and the recovery rate of the tin-silver symbiotic polymetallic ore is increased. The contents of silver, copper and tin in the tailings are obviously reduced, and efficient utilization of resources and reduction of solid wastes are realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mineral separation, in particular to a beneficiation method of tin-silver associated polymetallic ore and application thereof. BACKGROUND

[0002] Tin-silver associated polymetallic ore, especially cassiterite-lead-antimony-zinc sulfide ore, is an important mineral resource, which is rich in valuable metals such as tin (Sn), lead (Pb), antimony (Sb) and zinc (Zn), and often associated with precious metals such as silver (Ag) and copper (Cu). Efficient recovery of such ores is conducive to improving resource utilization and enhancing economic value.

[0003] However, for a long time, the experimental research and production process of tin-silver associated polymetallic ore have paid more attention to the recovery of sulfide minerals, gravity separation of cassiterite and flotation of fine-grained cassiterite, but less attention to reducing tin loss in the recovery process of sulfide minerals, resulting in high tin content in sulfide ore, which leads to large loss of tin. In addition, it is difficult to recover tin from tailings after the flotation of silver, copper and other metals in tin-silver associated polymetallic ore. Therefore, there is an urgent need to provide a new beneficiation method to solve the above problems.

[0004] In view of this, the present application is proposed. SUMMARY

[0005] The present application aims to provide a beneficiation method of tin-silver associated polymetallic ore and application thereof.

[0006] The present application is implemented as follows: In a first aspect, the present application provides a beneficiation method of tin-silver associated polymetallic ore, which includes grinding the tin-silver associated polymetallic ore, then obtaining undersize minerals through a high-frequency screen, carrying out silver-copper flotation on the undersize minerals to obtain silver-copper concentrate and silver-copper tailings, carrying out lead-zinc-sulfur flotation on the silver-copper tailings to obtain lead concentrate and zinc-sulfur tailings, and carrying out zinc-sulfur flotation on the zinc-sulfur tailings to obtain zinc-sulfur concentrate and tin-sulfur tailings.

[0007] The pulp concentration in the grinding process is 50-60wt%.

[0008] In the lead-zinc-sulfur flotation process, a first depressant is added, and the first depressant includes a mixture of sodium o-nitrobenzoate and zinc diethyldithiocarbamate.

[0009] In an optional embodiment, the lead-zinc-sulfur flotation process includes: carrying out flotation on the silver-copper tailings according to the steps of one roughing, two cleanings and three scavengings, and sequentially returning the tailings of each cleaning and the concentrate of scavenging to the previous operation.

[0010] In an optional embodiment, the parameters of lead-zinc-sulfur flotation include at least one of the following 1) to 6): 1) The reagents added during roughing include 200-300 g / t of the first inhibitor, 100-120 g / t of the collector, and 10-15 g / t of the frother.

[0011] 2) The reagents added during the fine selection process include 150~160g / t of the first inhibitor.

[0012] 3) The reagents added during scavenging I include 80-90 g / t of collector; the reagents added during scavenging II include 80-85 g / t of collector.

[0013] 4) In the first depressant used in the lead-zinc-sulfur flotation process, the mass ratio of sodium o-nitrobenzoate and zinc diethyldithiocarbamate is 1~5:8~10.

[0014] 5) The pH of the lead-zinc-sulfur flotation system is 6-7.

[0015] 6) The collectors used in the lead-zinc-sulfur flotation process include any one of xanthate and black powder; the frothers include any one of pine oil and camphor oil.

[0016] In an optional implementation, the oversize minerals obtained from the high-frequency screen are returned for further grinding.

[0017] In an optional embodiment, the particle size distribution of the slurry during the grinding process is 75-80% -0.074 mm.

[0018] In an optional implementation, the zinc-sulfur flotation process includes: flotating the zinc-sulfur tailings in the steps of one roughing, two cleaning, and three scavenging, and returning the tailings from each cleaning stage and the concentrate from the scavenging stage to the next stage operation in sequence.

[0019] In an optional implementation, the parameters for zinc-sulfur flotation include at least one of the following 1) to 2): 1) The reagents added during the roughing process include 100-300 g / t of the second inhibitor and 20-50 g / t of the collector.

[0020] 2) The second inhibitor includes 2-(phosphonomethylthio)acetic acid; the collector used in the zinc-sulfur flotation process includes either xanthate or eucalyptus oil.

[0021] In an optional implementation, the silver-copper flotation process includes: flotating the tin-silver polymetallic ore in the steps of one roughing, two cleaning, and two scavenging, with the tailings from each cleaning stage and the concentrate from the scavenging stage being returned sequentially to the next stage of operation.

[0022] In an optional embodiment, the collector added during the silver-copper flotation process includes either sodium ethyl xanthate or butylamine black powder.

[0023] Secondly, the present invention provides an application of the method as described in any of the foregoing embodiments in improving the tin recovery rate in tin-silver symbiotic polymetallic ores.

[0024] The present invention has the following beneficial effects: This invention provides a beneficiation method for tin-silver polymetallic ores and its application. By controlling the slurry concentration during grinding, the cassiterite and sulfide minerals are fully liberated. Then, a first inhibitor is added during the lead-zinc-sulfur flotation process. The first inhibitor is a mixture of sodium o-nitrobenzoate and zinc diethyldithiocarbamate. The nitro group in sodium o-nitrobenzoate and the amino group in zinc diethyldithiocarbamate synergistically undergo a complexation reaction with the zinc-sulfur minerals in the silver-copper tailings. The zinc-sulfur minerals enter the tailings, and the lead floats up and separates from the zinc-sulfur tailings to obtain lead concentrate. This avoids tin from being mixed into the lead concentrate and reduces tin loss. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 A flowchart illustrating the beneficiation method for tin-silver polymetallic ore provided in an embodiment of the present invention; Figure 2 A flowchart of silver-copper flotation provided in an embodiment of the present invention; Figure 3 A flowchart for lead-zinc-sulfur flotation provided in an embodiment of the present invention; Figure 4 A flowchart of zinc-sulfur flotation provided for an embodiment of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0028] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0029] The unit "g / t" mentioned in this invention refers to the number of grams of reagent added per ton of mineral to be treated. The mineral to be treated is the raw material mineral for this step. For example, in the lead-zinc-sulfur flotation process, 200-300 g / t of the first inhibitor is added during roughing, which means 200-300 g of the first inhibitor is added to each ton of silver-copper tailings.

[0030] In a first aspect, the present invention provides a beneficiation method for tin-silver polymetallic ore, comprising grinding the tin-silver polymetallic ore, passing it through a high-frequency screen to obtain undersize minerals, subjecting the undersize minerals to silver-copper flotation to obtain silver-copper concentrate and silver-copper tailings; subjecting the silver-copper tailings to lead-zinc-sulfur flotation to obtain lead concentrate and zinc-sulfur tailings; and subjecting the zinc-sulfur tailings to zinc-sulfur flotation to obtain zinc-sulfur concentrate and tin-sulfur tailings.

[0031] The slurry concentration during the grinding process is 50-60 wt%.

[0032] A first inhibitor is added during the lead-zinc-sulfur flotation process. The first inhibitor consists of a mixture of sodium o-nitrobenzoate and zinc diethyldithiocarbamate.

[0033] By controlling the pulp concentration during grinding, the cassiterite and sulfide minerals are fully liberated. Then, a first inhibitor is added during the lead-zinc-sulfur flotation process. The first inhibitor is a mixture of sodium o-nitrobenzoate and zinc diethyldithiocarbamate. The nitro group in sodium o-nitrobenzoate and the amino group in zinc diethyldithiocarbamate synergistically react with the zinc-sulfur minerals in the silver-copper tailings to form a complex. The zinc-sulfur minerals enter the tailings, and the lead floats up and separates from the zinc-sulfur tailings to obtain lead concentrate. This avoids tin from being mixed into the lead concentrate and reduces tin loss.

[0034] Please refer to Figure 1 In a preferred embodiment, the present invention provides a beneficiation method for tin-silver polymetallic ore, comprising the following steps: S01, Grinding Tin-silver polymetallic ore is ground to obtain grinding products. The grinding products are then screened through a high-frequency screen to obtain oversize and undersize minerals. The oversize minerals are returned for grinding until their particle size can pass through the high-frequency screen, becoming undersize minerals. The undersize minerals are used as raw materials for subsequent silver-copper flotation.

[0035] During the grinding process, the slurry concentration is 50-60 wt%, and mineral particles with a particle size distribution of -0.074 mm account for 75-80% of the total mineral particle mass.

[0036] The inventors discovered that simultaneously recovering sulfide ore and reducing its tin content is a highly complex problem. On the one hand, cassiterite is easily over-crushed, leading to muddy residue that is difficult to recover. On the other hand, if the sulfide minerals are too coarse, exceeding the upper limit of conventional flotation particle size (e.g., 0.2-0.25 mm), the coarse cassiterite particles are difficult to float, and these particles significantly impact cassiterite recovery during subsequent shaking table operations. Furthermore, if the sulfide ore is too fine, a large amount of reagent is required, resulting in the entrainment of fine cassiterite particles, which also causes cassiterite loss in the froth of the sulfide ore.

[0037] This invention involves grinding tin-silver polymetallic ore and then using a high-frequency screen to promptly separate mineral particles with a size suitable for subsequent flotation processes. This avoids the problem of over-grinding of cassiterite, which leads to sludge formation and difficulty in recovery. By controlling the slurry concentration within the aforementioned range during grinding, combined with the particle size distribution control, the cassiterite in the tin-silver polymetallic ore is precisely dissociated from the sulfide ore during grinding, facilitating subsequent separation and recovery of cassiterite.

[0038] Preferably, the grinding process employs multi-stage grinding to ensure that cassiterite is just properly dissociated from the sulfide ore.

[0039] S02, silver-copper flotation The undersize minerals obtained in step S01 are subjected to silver-copper flotation to obtain silver-copper concentrate and silver-copper tailings. The main metallic elements in the silver-copper concentrate are Ag and Cu; the elements contained in the silver-copper tailings include Pb, Zn, Sn, and S. Since metals such as Pb and Zn exist in the form of sulfides in the silver-copper tailings, the silver-copper tailings belong to a type of sulfide mineral.

[0040] Please refer to Figure 2 In some preferred embodiments, the silver-copper flotation process includes: flotating the tin-silver polymetallic ore in the steps of one roughing, two cleaning and two scavenging, and returning the tailings from each cleaning stage and the concentrate from the scavenging stage to the next stage of operation in sequence. For example, the tailings from Cleaning Stage I are returned to the roughing stage, and the concentrate from Scavenging Stage I is returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0041] In an optional embodiment, the collector added during the silver-copper flotation process includes either sodium ethyl xanthate or butylamine black powder.

[0042] SO3, lead-zinc-sulfur flotation The silver-copper tailings obtained in step S02 are subjected to lead-zinc-sulfur flotation to obtain lead concentrate and zinc-sulfur tailings. The main element in the lead concentrate is Pb; the elements contained in the zinc-sulfur tailings include Zn, Sn, and S.

[0043] Since tin is enriched in the silver-copper tailings obtained in step S02, in order to avoid cassiterite being mixed into the sulfide ore during the recovery of sulfide ore, a first inhibitor is added during the lead-zinc-sulfur flotation process. The first inhibitor consists of a mixture of sodium o-nitrobenzoate and zinc diethyldithiocarbamate.

[0044] The nitro group in sodium o-nitrobenzoate and the amino group in zinc diethyldithiocarbamate synergistically undergo a complexation reaction with zinc-sulfur minerals in silver-copper tailings. The zinc-sulfur minerals enter the tailings, and the lead floats up and separates from the zinc-sulfur tailings to obtain lead concentrate, thus avoiding tin from being mixed into the lead concentrate and reducing tin loss.

[0045] Please refer to Figure 3 In an optional implementation, the lead-zinc-sulfur flotation process includes: flotating silver-copper tailings in the steps of one roughing, two cleaning, and three scavenging. The tailings from each cleaning stage and the concentrates from the scavenging are returned to the next stage of operation in sequence. For example, tailings from Cleaning Stage I are returned to the roughing stage, and concentrates from Scavenging Stage I are returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0046] In an optional implementation, the parameters for lead-zinc-sulfur flotation include at least one of the following 1) to 6): 1) The reagents added during roughing include 200-300 g / t of the first inhibitor, 100-120 g / t of the collector, and 10-15 g / t of the frother.

[0047] 2) The reagents added during fine I purification include 150~160g / t of the first inhibitor; preferably, no reagents are added during fine II purification.

[0048] 3) The reagents added during scavenging I include 80-90 g / t of collector; the reagents added during scavenging II include 80-85 g / t of collector.

[0049] 4) In the first depressant used in the lead-zinc-sulfur flotation process, the mass ratio of sodium o-nitrobenzoate and zinc diethyldithiocarbamate is 1~5:8~10.

[0050] 5) The pH of the lead-zinc-sulfur flotation system is 6-7.

[0051] 6) The collectors used in the lead-zinc-sulfur flotation process include any one of xanthate and black powder; the frothers include any one of pine oil and camphor oil.

[0052] By controlling the parameters of lead-zinc-sulfur flotation within the above range, it is beneficial for lead to float up under the action of the collector to obtain lead concentrate, while elements such as zinc, sulfur, and tin settle with the first inhibitor and enter the zinc-sulfur tailings, thus achieving the separation of Pb from other metallic minerals.

[0053] S04, Zinc-Sulfur Flotation The zinc-sulfur tailings obtained in step S03 were subjected to zinc-sulfur flotation to obtain zinc-sulfur concentrate and tin-sulfur tailings. The main metallic element in the zinc-sulfur concentrate is Zn, which exists in the form of sulfides; the tin-sulfur tailings contain Sn and S (mainly in the form of pyrite FeS2).

[0054] Please refer to Figure 4 In an optional implementation, the zinc-sulfur flotation process includes: flotating zinc-sulfur tailings in the steps of one roughing, two cleaning, and three scavenging. The tailings from each cleaning stage and the concentrates from the scavenging are returned to the next stage of operation in sequence. For example, tailings from Cleaning Stage I are returned to the roughing stage, and concentrates from Scavenging Stage I are returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0055] In an optional implementation, the parameters for zinc-sulfur flotation include at least one of the following 1) to 2): 1) The reagents added during the roughing process include 100-300 g / t of the second inhibitor and 20-50 g / t of the collector.

[0056] 2) The second inhibitor includes 2-(phosphonomethylthio)acetic acid; the collector used in the zinc-sulfur flotation process includes either xanthate or eucalyptus oil.

[0057] By selecting 2-(phosphonomethylthio)acetic acid as the second inhibitor, its molecular structure is HOOC-CH2-S-CH2-PO(OH)2. This inhibitor is the first to integrate a triple functional group consisting of a thiol group (-S-), a phosphonic acid group (-PO(OH)2), and a carboxyl group (-COOH), achieving highly efficient inhibition of pyrite through synergistic effects. Specifically, the thiol group strongly adsorbs onto the Fe sites on the pyrite surface, the phosphonic acid group constructs a hydrophilic barrier and enhances its resistance to hard water, and the carboxyl group enhances solubility and provides electrostatic repulsion, thereby improving the separation of Zn from other metal elements. This second inhibitor is broadly effective within a pH range of 4–10, and it requires low reagent dosage, is environmentally friendly, and has a green synthesis process.

[0058] The preparation method of 2-(phosphonomethylthio)acetic acid includes: Step 1: Take 100g of biomass methanethiol extracted from methionine production waste liquid and 150ml of industrial chloroacetic acid, and carry out a catalytic condensation reaction in an aqueous medium at room temperature. After the reaction is completed, perform vacuum concentration technology at 100~150℃ and 1.5 kPa to preferentially and directionally precipitate high-purity industrial-grade sodium chloride (NaCl) crystals to obtain (methylthio)acetic acid.

[0059] Step 2: The (methylthio)acetic acid obtained in Step 1 was methylated to generate methyl (methylthio)acetic acid. At 60 °C and 10 MPa, the methyl ester and dimethyl phosphite were reacted in a supercritical carbon dioxide (scCO2) continuous phase using a 0.5–1.5 mol% core-shell magnetic TiO2@Fe3O4 nanocatalyst under the synergistic effect of a 150–160 W microwave radiation field for 30 min.

[0060] Step 3: The phosphonate product obtained in Step 2 is hydrolyzed at 40°C and pH 5.0 to obtain 2-(phosphonomethylthio)acetic acid with the molecular formula CH3SCH2P(O)(OH)2.

[0061] Secondly, the present invention provides an application of the method as described in any of the foregoing embodiments in improving the tin recovery rate in tin-silver symbiotic polymetallic ores.

[0062] Example 1 This embodiment provides a beneficiation method for a tin-silver polymetallic ore, wherein the tin-silver polymetallic ore is a tin-bearing polymetallic ore in a certain area of ​​Inner Mongolia, and its main mineral composition includes cassiterite, pyrite, quartz, muscovite, biotite, kaolinite, and dolomite. The average grade of silver, the main valuable element in the tin-silver polymetallic ore, is 160%, and the average grade of sulfur is 6.62%.

[0063] The specific mineral processing methods are as follows: S01, Grinding The tin-silver polymetallic ore is ground using a semi-autogenous mill, and then screened by a high-frequency screen to obtain oversize and undersize minerals. The oversize minerals are returned for further grinding until their particle size can pass through the high-frequency screen, becoming undersize minerals. The undersize minerals are used as raw materials for subsequent silver-copper flotation.

[0064] During the grinding process, the slurry concentration is 55 wt%, and mineral particles with a particle size distribution of -0.074 mm account for 75% of the total mineral particle mass.

[0065] S02, silver-copper flotation The undersize minerals obtained in step S01 are subjected to silver-copper flotation to obtain silver-copper concentrate and silver-copper tailings. The main metallic elements in the silver-copper concentrate are Ag and Cu; the elements contained in the silver-copper tailings include Pb, Zn, Sn, and S.

[0066] The silver-copper flotation process includes: flotation of tin-silver polymetallic ores in the form of one roughing, two cleaning, and two scavenging steps. The tailings from each cleaning stage and the concentrate from the scavenging are returned to the next stage of operation in sequence. For example, the tailings from Cleaning Stage I are returned to the roughing stage, and the concentrate from Scavenging Stage I is returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0067] In the silver-copper flotation process, the collector added is sodium ethyl xanthate, and the amount added is 30g / t.

[0068] SO3, lead-zinc-sulfur flotation The silver-copper tailings obtained in step S02 are subjected to lead-zinc-sulfur flotation to obtain lead concentrate and zinc-sulfur tailings. The main element in the lead concentrate is Pb; the elements contained in the zinc-sulfur tailings include Zn, Sn, and S.

[0069] The flotation process for lead, zinc, and sulfur includes: maintaining the pH of the system at 6-7, flotating silver and copper tailings in the steps of one roughing, two cleaning, and three scavenging, and returning the tailings from each cleaning stage and the concentrates from the scavenging stage to the next stage in sequence. For example, tailings from Cleaning Stage I are returned to the roughing stage, and concentrates from Scavenging Stage I are returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0070] During the roughing process, 200 g / t of the first inhibitor, 100 g / t of xanthate, and 10 g / t of pine oil are added sequentially to the silver-copper tailings.

[0071] For Refinement I, 150g / t of the first inhibitor is added; for Refinement II, no additional drugs are added.

[0072] Add 80g / t of xanthate during scavenging I; add 80g / t of xanthate during scavenging II.

[0073] The first inhibitor mentioned above is a mixture of sodium o-nitrobenzoate and zinc diethyldithiocarbamate in a mass ratio of 1:8.

[0074] S04, Zinc-Sulfur Flotation The zinc-sulfur tailings obtained in step S03 were subjected to zinc-sulfur flotation to obtain zinc-sulfur concentrate and tin-sulfur tailings. The main metallic element in the zinc-sulfur concentrate is Zn, which exists in the form of sulfides; the tin-sulfur tailings contain Sn and S (mainly in the form of pyrite FeS2).

[0075] The zinc-sulfur flotation process includes: flotation of zinc-sulfur tailings in three steps: one roughing, two cleaning, and three scavenging. The tailings from each cleaning stage and the concentrates from the scavenging are returned to the next stage of operation in sequence. For example, tailings from Cleaner I are returned to the roughing stage, and concentrates from Scavenger I are returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0076] During the roughing process, 100 g / t of a second inhibitor and 20 g / t of xanthate were added, wherein the second inhibitor was 2-(phosphonomethylthio)acetic acid. In the first and second sweeps, 30 g / t and 20 g / t of xanthate were added as collectors, respectively.

[0077] The preparation method of the aforementioned second inhibitor, namely 2-(phosphonomethylthio)acetic acid, includes: Step 1: Take 100g of biomass methanethiol extracted from methionine production waste liquid and 150ml of industrial chloroacetic acid, and carry out a catalytic condensation reaction in an aqueous medium at room temperature. After the reaction is completed, perform vacuum concentration at 120℃ and 1.5 kPa to preferentially and directionally precipitate high-purity industrial-grade sodium chloride (NaCl) crystals to obtain (methylthio)acetic acid.

[0078] Step 2: The (methylthio)acetic acid obtained in Step 1 was methylated to generate methyl (methylthio)acetic acid. At 60 °C and 10 MPa, the methyl ester and dimethyl phosphite were reacted in a supercritical carbon dioxide (scCO2) continuous phase using a 0.5 mol% core-shell magnetic TiO2@Fe3O4 nanocatalyst under the synergistic effect of a 150 W microwave radiation field for 30 min.

[0079] Step 3: The phosphonate product obtained in Step 2 is hydrolyzed at 40°C and pH 5.0 to obtain 2-(phosphonomethylthio)acetic acid with the molecular formula CH3SCH2P(O)(OH)2.

[0080] Example 2 This embodiment provides a beneficiation method for a tin-silver polymetallic ore, wherein the tin-silver polymetallic ore is a tin-bearing polymetallic ore in a certain area of ​​Inner Mongolia, and its main mineral composition includes cassiterite, pyrite, quartz, muscovite, biotite, kaolinite, and dolomite. The average grade of silver, the main valuable element in the tin-silver polymetallic ore, is 156%, and the average grade of sulfur is 5.91%.

[0081] The specific mineral processing methods are as follows: S01, Grinding The tin-silver polymetallic ore is ground using a semi-autogenous mill, and then screened by a high-frequency screen to obtain oversize and undersize minerals. The oversize minerals are returned for further grinding until their particle size can pass through the high-frequency screen, becoming undersize minerals. The undersize minerals are used as raw materials for subsequent silver-copper flotation.

[0082] During the grinding process, the slurry concentration is 50 wt%, and mineral particles with a particle size distribution of -0.074 mm account for 75% of the total mineral particle mass.

[0083] S02, silver-copper flotation The undersize minerals obtained in step S01 are subjected to silver-copper flotation to obtain silver-copper concentrate and silver-copper tailings. The main metallic elements in the silver-copper concentrate are Ag and Cu; the elements contained in the silver-copper tailings include Pb, Zn, Sn, and S.

[0084] The silver-copper flotation process includes: flotation of tin-silver polymetallic ores in the form of one roughing, two cleaning, and two scavenging steps. The tailings from each cleaning stage and the concentrate from the scavenging are returned to the next stage of operation in sequence. For example, the tailings from Cleaning Stage I are returned to the roughing stage, and the concentrate from Scavenging Stage I is returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0085] In the silver-copper flotation process, the collector added is sodium ethyl xanthate, and the amount added is 50g / t.

[0086] SO3, lead-zinc-sulfur flotation The silver-copper tailings obtained in step S02 are subjected to lead-zinc-sulfur flotation to obtain lead concentrate and zinc-sulfur tailings. The main element in the lead concentrate is Pb; the elements contained in the zinc-sulfur tailings include Zn, Sn, and S.

[0087] The flotation process for lead, zinc, and sulfur includes: maintaining the pH of the system at 6-7, flotating silver and copper tailings in the steps of one roughing, two cleaning, and three scavenging, and returning the tailings from each cleaning stage and the concentrates from the scavenging stage to the next stage in sequence. For example, tailings from Cleaning Stage I are returned to the roughing stage, and concentrates from Scavenging Stage I are returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0088] During roughing, 250 g / t of the first inhibitor, 110 g / t of xanthate, and 15 g / t of pine oil are added sequentially to the silver-copper tailings.

[0089] During the first-stage purification process, 160g / t of the first inhibitor is added; during the second-stage purification process, no additional drugs are added.

[0090] Add 80g / t of xanthate during scavenging I; add 85g / t of xanthate during scavenging II.

[0091] The first inhibitor mentioned above is a mixture of sodium o-nitrobenzoate and zinc diethyldithiocarbamate in a mass ratio of 2:8.

[0092] S04, Zinc-Sulfur Flotation The zinc-sulfur tailings obtained in step S03 were subjected to zinc-sulfur flotation to obtain zinc-sulfur concentrate and tin-sulfur tailings. The main metallic element in the zinc-sulfur concentrate is Zn, which exists in the form of sulfides; the tin-sulfur tailings contain Sn and S (mainly in the form of pyrite FeS2).

[0093] The zinc-sulfur flotation process includes: flotation of zinc-sulfur tailings in three steps: one roughing, two cleaning, and three scavenging. The tailings from each cleaning stage and the concentrates from the scavenging are returned to the next stage of operation in sequence. For example, tailings from Cleaner I are returned to the roughing stage, and concentrates from Scavenger I are returned to the roughing stage. Through the flotation cycle process, the grade of each metal element is improved.

[0094] During the roughing process, 150 g / t of a second inhibitor and 30 g / t of xanthate were added, wherein the second inhibitor was 2-(phosphonomethylthio)acetic acid.

[0095] Example 3: This embodiment provides a beneficiation method for tin-silver polymetallic ore. Compared with Example 1, the main difference is that the reaction temperature in step 1 of the preparation method of 2-(phosphonomethylthio)acetic acid is 120°C.

[0096] Example 4: This embodiment provides a beneficiation method for tin-silver polymetallic ore. Compared with Example 1, the main difference is that the reaction temperature in step 1 of the preparation method of 2-(phosphonomethylthio)acetic acid is 150°C.

[0097] Example 5: This embodiment provides a beneficiation method for tin-silver symbiotic polymetallic ore. Compared with Example 1, the main difference is that step 2 of the preparation method of 2-(phosphonomethylthio)acetic acid uses a 1.5 mol% core-shell structured magnetic TiO2@Fe3O4 nanocatalyst.

[0098] Example 6: This embodiment provides a beneficiation method for tin-silver symbiotic polymetallic ore. Compared with Example 1, the main difference is that step 2 of the preparation method of 2-(phosphonomethylthio)acetic acid uses 0.5 mol% core-shell structured magnetic TiO2@Fe3O4 nanocatalyst, and the reaction time is 60 min under the synergistic effect of a 160W microwave radiation field.

[0099] Comparative Example 1 This comparative example provides a beneficiation method for a tin-silver polymetallic ore, which is a tin-bearing polymetallic ore from a certain area in Inner Mongolia. The main mineral components are cassiterite, pyrite, quartz, muscovite, biotite, kaolinite, and dolomite. The average grade of silver, the main valuable element in the tin-silver polymetallic ore, is 164%, and the average grade of sulfur is 6.32%.

[0100] The mineral processing method is similar to that in Example 1, except that the inhibitor in step S03 is 1000 g / t of lime.

[0101] Comparative Example 2 This comparative example provides a beneficiation method for a tin-silver polymetallic ore, which is a tin-bearing polymetallic ore from a certain area in Inner Mongolia. The main mineral components are cassiterite, pyrite, quartz, muscovite, biotite, kaolinite, and dolomite. The average grade of silver, the main valuable element in the tin-silver polymetallic ore, is 159%, and the average grade of sulfur is 5.95%.

[0102] The mineral processing method is similar to that in Example 1, except that in step S04, zinc-sulfur flotation uses a common depressant and lime.

[0103] Comparative Example 3 This comparative example provides a beneficiation method for a tin-silver polymetallic ore, which is a tin-bearing polymetallic ore from a certain location in Inner Mongolia. The main mineral components are cassiterite, pyrite, quartz, muscovite, biotite, kaolinite, and dolomite. The average grade of silver, the main valuable element in the tin-silver polymetallic ore, is 123%, and the average grade of sulfur is 6.57%.

[0104] The mineral processing method is similar to that in Example 1, except that no second inhibitor is added.

[0105] Comparative Example 4 This comparative example provides a beneficiation method for a tin-silver polymetallic ore, which is a tin-bearing polymetallic ore from a certain area in Inner Mongolia. The main mineral components are cassiterite, pyrite, quartz, muscovite, biotite, kaolinite, and dolomite. The average grade of silver, the main valuable element in the tin-silver polymetallic ore, is 115%, and the average grade of sulfur is 9.16%.

[0106] The mineral processing method is similar to that in Example 1, except that the inhibitor in step S03 is 2000 g / t of potassium dichromate.

[0107] Comparative Example 5 This comparative example provides a beneficiation method for a tin-silver polymetallic ore, which is a tin-bearing polymetallic ore from a certain area in Inner Mongolia. The main mineral components are cassiterite, pyrite, quartz, muscovite, biotite, kaolinite, and dolomite. The average grade of silver, the main valuable element in the tin-silver polymetallic ore, is 103%, and the average grade of sulfur is 15.26%.

[0108] The mineral processing method is similar to that in Example 1, except that the inhibitor in step S03 is sodium humate 2500g / t.

[0109] Experimental Example 1 The grades of each element in the tin-silver polymetallic ores obtained by the methods provided in Examples 1-6 and Comparative Examples 1-5 were tested respectively, and the results are shown in Table 1.

[0110] Table 1. Grades of various elements in tin-silver polymetallic ores

[0111] As shown in Table 1, the beneficiation method for tin-silver polymetallic ore provided in this embodiment of the invention can, by optimizing the flotation process and innovating the reagent formulation, enhance the recovery efficiency of valuable metals, significantly reduce the silver, copper and tin content in the tailings, and achieve efficient resource utilization and solid waste reduction, taking into account the complex characteristics of tin-silver polymetallic ore.

[0112] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A beneficiation method for a tin-silver polymetallic ore, characterized in that, The process includes grinding a tin-silver polymetallic ore, passing it through a high-frequency screen to obtain undersize minerals, performing silver-copper flotation on the undersize minerals to obtain silver-copper concentrate and silver-copper tailings; performing lead-zinc-sulfur flotation on the silver-copper tailings to obtain lead concentrate and zinc-sulfur tailings; and performing zinc-sulfur flotation on the zinc-sulfur tailings to obtain zinc-sulfur concentrate and tin-sulfur tailings. The pulp concentration during the grinding process is 50-60 wt%; A first inhibitor is added during the lead-zinc-sulfur flotation process. The first inhibitor comprises a mixture of sodium o-nitrobenzoate and zinc diethyldithiocarbamate.

2. The method according to claim 1, characterized in that, The lead-zinc-sulfur flotation process includes: flotating the silver-copper tailings in the steps of one roughing, two cleaning, and three scavenging, and returning the tailings from each cleaning stage and the concentrate from the scavenging stage to the next stage of operation in sequence.

3. The method according to claim 2, characterized in that, The parameters for lead-zinc-sulfur flotation include at least one of the following 1) to 6): 1) The reagents added during roughing include 200-300 g / t of the first inhibitor, 100-120 g / t of the collector, and 10-15 g / t of the frother; 2) The reagents added during the fine selection process include 150-160g / t of the first inhibitor; 3) The reagents added during scavenging I include 80-90 g / t of collector; the reagents added during scavenging II include 80-85 g / t of collector. 4) In the first inhibitor used in the lead-zinc-sulfur flotation process, the mass ratio of sodium o-nitrobenzoate and zinc diethyldithiocarbamate is 1~5:8~10; 5) The pH of the lead-zinc-sulfur flotation system is 6-7; 6) The collectors used in the lead-zinc-sulfur flotation process include any one of xanthate and black powder; the frothers include any one of pine oil and camphor oil.

4. The method according to claim 1, characterized in that, The oversize minerals obtained from the high-frequency screen are returned for further grinding.

5. The method according to claim 4, characterized in that, During the grinding process, the particle size distribution of the slurry is -0.074 mm, accounting for 75-80%.

6. The method according to claim 1, characterized in that, The zinc-sulfur flotation process includes: flotating the zinc-sulfur tailings in the steps of one roughing, two cleaning, and three scavenging, and returning the tailings from each cleaning stage and the concentrate from the scavenging stage to the next stage of operation in sequence.

7. The method according to claim 6, characterized in that, The parameters for zinc-sulfur flotation include at least one of the following 1) to 2): 1) The reagents added during roughing include 100-300 g / t of second inhibitor and 20-50 g / t of collector; 2) The second inhibitor includes 2-(phosphonomethylthio)acetic acid; the collector used in the zinc-sulfur flotation process includes any one of xanthate and eucalyptus oil.

8. The method according to claim 1, characterized in that, The silver-copper flotation process includes: flotating the tin-silver polymetallic ore in the steps of one roughing, two cleaning and two scavenging, and returning the tailings from each cleaning stage and the concentrate from the scavenging stage to the next stage operation in sequence.

9. The method according to claim 8, characterized in that, During the silver-copper flotation process, the collectors added include either sodium ethyl xanthate or butylammonium black powder.

10. The application of the method as described in any one of claims 1 to 9 in improving the recovery rate of tin in tin-silver polymetallic ores.

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