A beneficiation process for recovering tin from iron-tin ore gravity separation tailings

Abstract

This invention discloses a mineral processing technology for recovering tin from gravity separation tailings of iron-tin ore. The process includes the following steps: S1, classifying the iron-tin ore gravity separation tailings to obtain coarse and fine products; S2, classifying the coarse products to obtain three particle sizes: +0.3mm, -0.3mm +0.074mm, and -0.074mm; S3, grinding the +0.3mm particle size product to obtain a ground product; S4, combining and concentrating the fine and -0.074mm products to obtain overflow water and underflow; S5, subjecting the ground product and underflow to weak magnetic separation to obtain iron concentrate and iron tailings; S6, subjecting the sulfur tailings to desulfurization and arsenic removal flotation to obtain sulfur-arsenic concentrate and sulfur-arsenic tailings; S7, subjecting the sulfur-arsenic tailings to tin flotation to obtain tin flotation concentrate and tin flotation tailings; S8, subjecting the tin flotation concentrate to reverse flotation for impurity removal to obtain tin concentrate and arsenic concentrate. The process proposed in this invention treats iron-tin ore tailings to improve the quality and reduce impurities of tin concentrate, increasing the tin concentrate quality to 20%–30%.

Description

Technical fields:

[0001] This invention relates to the field of mineral processing technology, specifically to a mineral processing technology for recovering tin from iron-tin ore gravity separation tailings. Background technology:

[0002] In recent years, with the rapid development of the national economy, the utilization of metallic ore resources has increased year by year. To alleviate the current shortage of resources, the research and development of tailings resources has attracted increasing attention from the state. Iron-tin ore is a typical iron-tin symbiotic deposit, with representative deposits including Dading in Guangdong and Huanggang in Inner Mongolia. Tin is closely associated with magnetite and iron-bearing gangue, with fine-grained tin dissemination, mostly existing in colloidal form, making comprehensive utilization difficult. It also contains a small amount of tungsten resources. Most beneficiation plants only use gravity separation processes to recover some of the coarse-grained liberated cassiterite, resulting in the loss of fine-grained cassiterite into the tailings, causing resource waste. Adopting reasonable processes to achieve efficient recovery of tin and tungsten resources from iron-tin ore gravity separation tailings is crucial to improving my country's resource utilization level. Summary of the Invention:

[0003] This invention solves the problems existing in the prior art and provides a mineral processing technology for recovering tin from iron-tin ore gravity separation tailings. The process proposed in this invention can process iron-tin ore tailings containing 0.3% to 0.5% Sn (40% to 80% of Sn exists as cassiterite), 0.05% to 0.15% WO3, 15% to 20% TFe, 0.1% to 0.8% mFe, 0.3% to 0.8% S, and 0.5% to 1.5% As to obtain products such as tin concentrate, iron concentrate, sulfur-arsenic concentrate, and arsenic concentrate. Among them, the tin concentrate contains 10% to 30% Sn and 5% to 10% WO3, with a Sn recovery rate of 40% to 60% and a WO3 recovery rate of 50% to 70%, realizing the comprehensive utilization of tailings resources.

[0004] The purpose of this invention is to provide a mineral processing technology for recovering tin from iron-tin ore gravity separation tailings, comprising the following steps:

[0005] S1. Hydrocyclone Classification: The tailings of the iron-tin ore gravity separation are classified by hydrocyclone to obtain coarse and fine products. The hydrocyclone underrun nozzle φ is 50-100mm, the pressure is 0.1-0.3Mpa, and the classification efficiency of 0.074mm is 40%-60%.

[0006] S2. Grading: The coarse-grained product from step S1 is graded to obtain three product grades: +0.3mm, -0.3+0.074mm, and -0.074mm.

[0007] S3. Grinding: Grind the +0.3mm particle size product from step S2 to obtain the ground product;

[0008] S4. Concentration: Combine and concentrate the fine-particle product from step S1 and the -0.074mm product from step S2 to obtain overflow water and sediment.

[0009] S5. Weak magnetic separation: Weak magnetic separation is performed on the grinding product of step S3 and the sand in S4 to obtain iron concentrate and iron tailings.

[0010] S6. Desulfurization and arsenic flotation: The sulfur tailings from step S5 are subjected to desulfurization and arsenic removal flotation to obtain sulfur-arsenic concentrate and sulfur-arsenic tailings.

[0011] S7, Tin flotation: The sulfur and arsenic tailings from step S6 are subjected to tin flotation to obtain tin flotation concentrate and tin flotation tailings;

[0012] S8. Reverse flotation to remove impurities: The tin flotation concentrate from step S7 is subjected to reverse flotation to remove impurities, thereby obtaining tin concentrate and arsenic concentrate.

[0013] Preferably, the iron-tin ore gravity separation tailings mentioned in step S1 are the tailings after iron-tin ore has undergone magnetic separation of iron, flotation of zinc, and gravity separation of tin, containing 0.3%–0.5% Sn, 0.05%–0.15% WO3, 15%–20% TFe, 0.1%–0.8% mFe, 0.3%–0.8% S, and 0.5%–1.5% As. 40%–80% of the Sn in the iron-tin ore exists as cassiterite, and the remainder exists as colloidal tin or isomorphously in garnet.

[0014] Preferably, the φ of the hydrocyclone underpass nozzle is 50-100mm, the pressure is 0.15-0.25Mpa, and the 0.074mm classification efficiency is 52%-55%.

[0015] Preferably, the coarse-grained product in step S2 is classified by a high-frequency screen. The high-frequency screen is double-layered, wherein the Sn content is -0.074mm particle size > +0.3mm particle size > -0.3+0.074mm particle size. The -0.3+0.074mm particle size is directly discarded as waste, and its yield is 20% to 35%.

[0016] Preferably, in the grinding product described in step S3, 60% to 80% have a grinding fineness of -0.074 mm. The grinding equipment is an Isa mill or a vertical stirred mill.

[0017] Preferably, the concentration of the sediment in step S4 is 25% to 40%, and the solid content of the overflow water is <0.5%.

[0018] Preferably, the magnetic field strength for the weak magnetic separation in step S5 is 1500–3000 GS. More preferably, the magnetic field strength for the weak magnetic separation in step S5 is 2000–3000 GS.

[0019] Preferably, the desulfurization and arsenic removal flotation in step S6 adopts a closed-circuit flotation process of 1 roughing, 1 scavenging, and 1 cleaning. The reagents added for roughing include 50-100 g / t of copper sulfate, 100-200 g / t of pentyl xanthate, and 30-50 g / t of monohydric alcohol. The reagent added for scavenging is 50-100 g / t of pentyl xanthate. No reagents are added for cleaning. The monohydric alcohol is a fusel alcohol with the chemical formula R-OH, where R is selected from a hydrocarbon group with 6-10 carbon atoms.

[0020] Further optimization involves adopting a closed-circuit flotation process of 1 roughing, 1 scavenging, and 1 cleaning in step S6. The reagents added for roughing include 80-100 g / t of copper sulfate, 120-200 g / t of pentyl xanthate, and 30-50 g / t of monohydric alcohol. The reagents added for scavenging are 60-80 g / t of pentyl xanthate. No reagents are added for cleaning.

[0021] Preferably, the tin flotation in step S7 adopts a closed-circuit flotation process of 1 roughing, 2 scavenging, and 3 cleaning. The reagents added in the roughing stage include 300-600 g / t of lead nitrate, 500-1000 g / t of benzo[a]hydroxyxamic acid (GYB), 50-100 g / t of diesel oil, and 50-100 g / t of tributyl phosphate (TBP). The reagents added in the scavenging stage include 200-400 g / t of GYB, 30-60 g / t of benzo[a]hydroxyxamic acid (GYB), 50-100 g / t of diesel oil, and 50-100 g / t of tributyl phosphate (TBP). The reagents added to the scavenging process 2 include 100-200 g / t of GYB, 20-40 g / t of diesel oil, and 20-40 g / t of TBP. The reagents added to the fine selection process 1 are 200-300 g / t of water glass, the reagents added to the fine selection process 2 are 100-200 g / t of water glass, and the reagents added to the fine selection process 3 are 50-100 g / t of water glass.

[0022] Further optimization involves adding the following reagents to the roughing stage: 400–600 g / t of lead nitrate, 600–1000 g / t of benzohydroxyxamic acid (GYB), 50–100 g / t of diesel oil, and 50–100 g / t of tributyl phosphate (TBP). Adding the following reagents to the scavenging stage 1: 300–400 g / t of GYB, 30–60 g / t of diesel oil, and 30–60 g / t of TBP. Adding the following reagents to the scavenging stage 2: 150–200 g / t of GYB, 20–40 g / t of diesel oil, and 20–40 g / t of TBP.

[0023] Preferably, the reverse flotation impurity removal in step S8 adopts an open-circuit flotation process that combines 1 rougher and 2 concentrate tailings. The reagents added in the rougher include 1000-2000 g / t of sulfuric acid and 10-20 g / t of monohydric alcohol, while no reagents are added in the concentrate.

[0024] For further optimization, the reagents added in the roughing process include 1000-2000 g / t of sulfuric acid and 10-15 g / t of monohydric alcohol, while no reagents are added in the finishing process.

[0025] Preferably, steps S5-S8 yield tin concentrate, iron concentrate, sulfur-arsenic concentrate, and arsenic concentrate. The tin concentrate contains 10%–30% Sn and 5%–10% WO3, with a Sn recovery rate of 40%–60% and a WO3 recovery rate of 50%–70%. The iron concentrate is mainly composed of magnetite, the sulfur-arsenic concentrate is mainly composed of pyrite and arsenopyrite, and the arsenic concentrate is mainly composed of orthorhombic arsenopyrite.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] 1. This invention enables the pre-disposal of iron-tin ore tailings. Iron-tin ore tailings are abundant, and the overall processing cost is high. Disposal of the relatively well-recovered intermediate particles can effectively reduce the amount fed into the beneficiation process and improve operational efficiency.

[0028] 2. This invention achieves the improvement and reduction of impurities in tin concentrate. Tin flotation is subject to many interfering factors, including iron-bearing minerals, sulfide minerals, and clay minerals. Conventional processes result in a Sn grade of 2% to 5% in tin concentrate. Through reasonable magnetic separation, desulfurization and arsenic removal, tin beneficiation modification with water glass inhibition, and reverse flotation for impurity removal, the interference of various gangues is effectively reduced, and the quality of tin concentrate is improved to 20% to 30%.

[0029] 3. This invention achieves efficient and comprehensive recovery of tin and tungsten resources. Through a combination of reagents such as GYB, diesel oil, and TBP, selective collection of tin and tungsten and efficient flotation of fine-grained tin and tungsten particles are achieved.

[0030] 4. This invention achieves the harmless discharge of tailings. The ore contains a large amount of As, and the leaching toxicity of As exceeds the standard. This invention, while recovering tin and tungsten, achieves the separation and extraction of two main arsenic minerals, arsenopyrite and orthorhombic arsenopyrite, effectively reducing the As content of the tailings and making its leaching toxicity meet the standard. Attached image description:

[0031] Figure 1 This is a flowchart of the mineral processing technology for recovering tin from the tailings of iron-tin ore gravity separation according to the present invention. Detailed implementation method:

[0032] The following embodiments are further illustrations of the present invention, but not limitations thereof.

[0033] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention. Unless otherwise specified, the experimental materials and reagents used herein are commercially available products conventionally available in this technical field. Monohydric alcohols are fusel alcohols with the chemical formula R-OH, where R is selected from hydrocarbon groups having 6-10 carbon atoms. Preferably, in the following examples, the monohydric alcohol is 1-heptanol and / or 1-octanol.

[0034] Example 1

[0035] Reference Figure 1 A mineral processing technology for recovering tin from tailings of iron-tin ore gravity separation specifically includes the following steps:

[0036] S1. Hydrocyclone Classification: The tailings of the iron-tin ore gravity separation are classified by hydrocyclone. The hydrocyclone has a sand discharge nozzle φ of 50mm, a pressure of 0.15Mpa, and a classification efficiency of 55% for 0.074mm particles, to obtain coarse and fine products.

[0037] S2. High-frequency sieve classification: The coarse product from step S1 is classified using a high-frequency sieve to obtain three product grades: +0.3mm, -0.3+0.074mm, and -0.074mm. The high-frequency sieve is double-layered. The Sn content of the -0.074mm grade is greater than that of the +0.3mm grade, which is greater than that of the -0.3+0.074mm grade. The -0.3+0.074mm grade is discarded directly, and its yield is 25%.

[0038] S3. Grinding: Grind the +0.3mm particle size product from step S2 until the grinding fineness is -0.074mm, accounting for 69%, to obtain the ground product.

[0039] S4. Concentration: Combine the fine-particle product from step S1 and the -0.074mm product from step S2 into a thickener or concentration tank for sedimentation and concentration to obtain overflow water and sediment. The concentration of the concentrated sediment is 27%, and the solid content of the overflow water is 0.22%.

[0040] S5. Weak magnetic separation: The grinding product from step S3 and the sand from step S4 are subjected to weak magnetic separation with a magnetic field strength of 3000GS to obtain iron concentrate and iron tailings.

[0041] S6. Desulfurization and arsenic flotation: The sulfur tailings from step S5 are subjected to desulfurization and arsenic removal flotation using a closed-circuit flotation process of 1 rougher, 1 scavenger, and 1 cleaner. The reagents used for roughing include 80 g / t of copper sulfate, 150 g / t of pentyl xanthate, and 50 g / t of monohydric alcohol. The scavenger uses 75 g / t of pentyl xanthate. No reagents are added for cleaning, to obtain sulfur-arsenic concentrate and sulfur-arsenic tailings.

[0042] S7. Tin Flotation: The sulfur and arsenic tailings from step S6 are subjected to tin flotation using a closed-circuit flotation process of 1 roughing, 2 scavenging, and 3 cleaning. The reagents used in the roughing process include 400 g / t lead nitrate, 800 g / t benzoyl hydroxamic acid (GYB), 70 g / t C6-8 diesel oil, and 70 g / t tributyl phosphate (TBP). The reagents used in scavenging 1 include 400 g / t GYB, 40 g / t diesel oil, and 40 g / t TBP. The reagents used in scavenging 2 include 200 g / t GYB, 20 g / t diesel oil, and 20 g / t TBP. The reagents used in cleaning 1 are 300 g / t modified water glass, the reagents used in cleaning 2 are 200 g / t modified water glass, and the reagents used in cleaning 3 are 100 g / t modified water glass. Tin flotation concentrate and tin flotation tailings are obtained.

[0043] S8. Reverse flotation for impurity removal: The tin flotation concentrate from step S7 is subjected to reverse flotation for impurity removal. An open-circuit flotation process combining 1 rougher and 2 concentrates and tailings is adopted. The reagents used in the roughing process include 2000g / t of sulfuric acid and 10g / t of monohydric alcohol. No reagents are added in the cleaning process to obtain tin concentrate and arsenic concentrate.

[0044] Using the above process, a tin concentrate containing 23.25% Sn and 7.15% WO3 was obtained from a feed containing 0.43% Sn and 0.11% WO3, with tin and tungsten recoveries of 49.38% and 62.52%, respectively.

[0045] Example 2

[0046] Reference Figure 1 A mineral processing technology for recovering tin from tailings of iron-tin ore gravity separation specifically includes the following steps:

[0047] S1. Hydrocyclone Classification: The tailings of the iron-tin ore gravity separation are classified by hydrocyclone. The hydrocyclone has a sand discharge nozzle φ of 75mm, a pressure of 0.22Mpa, and a classification efficiency of 53% for 0.074mm particles, to obtain coarse and fine particles.

[0048] S2. High-frequency sieve classification: The coarse product from step S1 is classified using a high-frequency sieve to obtain three product grades: +0.3mm, -0.3+0.074mm, and -0.074mm. The high-frequency sieve is double-layered. The Sn content of the -0.074mm grade is greater than that of the +0.3mm grade, which is greater than that of the -0.3+0.074mm grade. The -0.3+0.074mm grade is discarded directly, and its yield is 27%.

[0049] S3. Grinding: Grind the +0.3mm particle size product from step S2 until the grinding fineness is -0.074mm, accounting for 63%, to obtain the ground product;

[0050] S4. Concentration: Combine the fine-particle product from step S1 and the -0.074mm product from step S2 into a thickener or concentration tank for sedimentation and concentration to obtain overflow water and sediment. The concentration of the concentrated sediment is 35%, and the solid content of the overflow water is 0.35%.

[0051] S5. Weak magnetic separation: The grinding product from step S3 and the sand from S4 are subjected to weak magnetic separation with a magnetic field strength of 2000GS to obtain iron concentrate and iron tailings.

[0052] S6. Desulfurization and arsenic flotation: The sulfur tailings from step S5 are subjected to desulfurization and arsenic removal flotation using a closed-circuit flotation process of 1 rougher, 1 scavenger, and 1 cleaner. The reagents used for roughing include 100 g / t of copper sulfate, 120 g / t of pentyl xanthate, and 30 g / t of monohydric alcohol. The reagents used for scavenging are 60 g / t of pentyl xanthate. No reagents are added for cleaning. Sulfur-arsenic concentrate and sulfur-arsenic tailings are obtained.

[0053] S7. Tin Flotation: The sulfur and arsenic tailings from step S6 are subjected to tin flotation using a closed-circuit flotation process of 1 roughing, 2 scavenging, and 3 cleaning. The reagents used for roughing include 400 g / t lead nitrate, 600 g / t benzoyl hydroxamic acid (GYB), 50 g / t C6-8 diesel oil, and 50 g / t tributyl phosphate (TBP). The reagents used for scavenging 1 include 300 g / t GYB, 30 g / t diesel oil, and 30 g / t TBP. The reagents used for scavenging 2 include 150 g / t GYB, 20 g / t diesel oil, and 20 g / t TBP. The reagents used for cleaning 1 are 200 g / t modified water glass, cleaning 2 are 100 g / t modified water glass, and cleaning 3 are 50 g / t modified water glass. Tin flotation concentrate and tin flotation tailings are obtained.

[0054] S8. Reverse flotation for impurity removal: The tin flotation concentrate from step S7 is subjected to reverse flotation for impurity removal. An open-circuit flotation process combining 1 rougher and 2 concentrates and tailings is adopted. The reagents used in the roughing process include 1000g / t of sulfuric acid and 10g / t of monohydric alcohol. No reagents are added in the cleaning process to obtain tin concentrate and arsenic concentrate.

[0055] Using the above process, a tin concentrate containing 20.35% Sn and 5.74% WO3 was obtained from a feed containing 0.38% Sn and 0.087% WO3, with tin and tungsten recoveries of 45.26% and 58.71%, respectively.

[0056] Example 3

[0057] Reference Figure 1 A mineral processing technology for recovering tin from tailings of iron-tin ore gravity separation specifically includes the following steps:

[0058] S1. Hydrocyclone Classification: The tailings of the iron-tin ore gravity separation are classified by hydrocyclone. The hydrocyclone has a sand discharge nozzle φ of 100mm, a pressure of 0.25Mpa, and a classification efficiency of 52% for 0.074mm particles, to obtain coarse and fine particles.

[0059] S2. High-frequency sieve classification: The coarse product from step S1 is classified using a high-frequency sieve to obtain three product grades: +0.3mm, -0.3+0.074mm, and -0.074mm. The high-frequency sieve is double-layered. The Sn content of the -0.074mm grade is greater than that of the +0.3mm grade, which is greater than that of the -0.3+0.074mm grade. The -0.3+0.074mm grade is discarded directly, and its yield is 22%.

[0060] S3. Grinding: Grind the +0.3mm particle size product from step S2 to a grinding fineness of -0.074mm accounting for 75%, and obtain the ground product.

[0061] S4. Concentration: Combine the fine-particle product from step S1 and the -0.074mm product from step S2 into a thickener or concentration tank for sedimentation and concentration to obtain overflow water and sediment. The concentration of the concentrated sediment is 30%, and the solid content of the overflow water is 0.29%.

[0062] S5. Weak magnetic separation: The grinding product from step S3 and the sand from S4 are subjected to weak magnetic separation with a magnetic field strength of 2000GS to obtain iron concentrate and iron tailings.

[0063] S6. Desulfurization and arsenic flotation: The sulfur tailings from step S5 are subjected to desulfurization and arsenic removal flotation using a closed-circuit flotation process of 1 rougher, 1 scavenger, and 1 cleaner. The reagents used for roughing include 100 g / t of copper sulfate, 200 g / t of pentyl xanthate, and 40 g / t of monohydric alcohol. The reagents used for scavenging are 80 g / t of pentyl xanthate. No reagents are added for cleaning. Sulfur-arsenic concentrate and sulfur-arsenic tailings are obtained.

[0064] S7. Tin Flotation: The sulfur and arsenic tailings from step S6 are subjected to tin flotation using a closed-circuit flotation process of 1 roughing, 2 scavenging, and 3 cleaning. The reagents used in the roughing process include 600 g / t lead nitrate, 1000 g / t benzoyl hydroxamic acid (GYB), 100 g / t C6-8 diesel oil, and 100 g / t tributyl phosphate (TBP). The reagents used in scavenging 1 include 400 g / t GYB, 60 g / t diesel oil, and 60 g / t TBP. The reagents used in scavenging 2 include 200 g / t GYB, 40 g / t diesel oil, and 40 g / t TBP. The reagents used in cleaning 1 are 300 g / t modified water glass, the reagents used in cleaning 2 are 200 g / t modified water glass, and the reagents used in cleaning 3 are 100 g / t modified water glass. Tin flotation concentrate and tin flotation tailings are obtained.

[0065] S8. Reverse flotation for impurity removal: The tin flotation concentrate from step S7 is subjected to reverse flotation for impurity removal. An open-circuit flotation process combining 1 rougher and 2 concentrates and tailings is adopted. The reagents used in the roughing process include 1500g / t of sulfuric acid and 15g / t of monohydric alcohol. No reagents are added in the cleaning process to obtain tin concentrate and arsenic concentrate.

[0066] Using the above process, a tin concentrate containing 22.32% Sn and 8.17% WO3 was obtained from a feed containing 0.48% Sn and 0.14% WO3, with tin and tungsten recoveries of 52.33% and 63.55%, respectively.

[0067] Comparative Example 1

[0068] The only difference from Example 1 is that step S5 is omitted, while the other steps and conditions are the same as in Example 1.

[0069] The results showed that for a feed containing 0.43% Sn and 0.11% WO3, a tin concentrate containing 12.15% Sn and 3.74% WO3 was obtained, with tin and tungsten recoveries of 40.33% and 57.55%, respectively. The decrease in tin and tungsten grade and recovery rate was mainly due to interference from magnetic iron.

[0070] Comparative Example 2

[0071] The only difference from Example 1 is that diesel oil is not added in step S7. The detailed steps are as follows: the sulfur and arsenic tailings from step S6 are subjected to tin flotation using a closed-circuit flotation process of 1 roughing, 2 scavenging, and 3 cleaning. The reagents used in the roughing process include 400 g / t of lead nitrate, 800 g / t of benzohydroxyxamic acid (GYB), and 140 g / t of tributyl phosphate (TBP). The reagents used in scavenging 1 include 400 g / t of GYB and 80 g / t of TBP. The reagents used in scavenging 2 include 200 g / t of GYB and 40 g / t of TBP. The reagents used in cleaning 1 are 300 g / t of modified water glass, the reagents used in cleaning 2 are 200 g / t of modified water glass, and the reagents used in cleaning 3 are 100 g / t of modified water glass. Tin flotation concentrate and tin flotation tailings are obtained. The other steps and conditions are the same as in Example 1.

[0072] The results showed that for a feed containing 0.43% Sn and 0.11% WO3, a tin concentrate containing 25.23% Sn and 6.32% WO3 was obtained, with tin and tungsten recoveries of 43.15% and 55.27%, respectively. The decrease in tin and tungsten recovery rates was mainly due to insufficient flotation recovery of some fine-grained minerals.

[0073] Comparative Example 3

[0074] The only difference from Example 1 is that TBP is not added in step S7. The detailed steps are as follows: the sulfur and arsenic tailings from step S6 are subjected to tin flotation using a closed-circuit flotation process of 1 roughing, 2 scavenging, and 3 cleaning. The reagents used in the roughing process include 400 g / t of lead nitrate, 800 g / t of benzohydroxyxamic acid (GYB), and 140 g / t of diesel oil. The reagents used in scavenging 1 include 400 g / t of GYB and 80 g / t of diesel oil. The reagents used in scavenging 2 include 200 g / t of GYB and 40 g / t of diesel oil. The reagents used in cleaning 1 are 300 g / t of modified water glass. The reagents used in cleaning 2 are 200 g / t of modified water glass. The reagents used in cleaning 3 are 100 g / t of modified water glass. Tin flotation concentrate and tin flotation tailings are obtained. Other steps and conditions are the same as in Example 1.

[0075] The results showed that for a feed containing 0.43% Sn and 0.11% WO3, a tin concentrate containing 27.32% Sn and 7.35% WO3 was obtained, with tin and tungsten recoveries of 35.23% and 47.66%, respectively. The significant decrease in tin and tungsten recovery rates was mainly due to the poor surface activity of the slurry and insufficient flotation efficiency.

[0076] Comparative Example 4

[0077] The only difference from Example 1 is that benzohydroxyxamic acid is not added in step S7. The detailed steps are as follows: the sulfur and arsenic tailings in step S6 are subjected to tin flotation using a closed-circuit flotation process of 1 roughing, 2 scavenging, and 3 cleaning. The reagents used in the roughing process include 400 g / t of lead nitrate, 470 g / t of C6-8 diesel oil, and 470 g / t of tributyl phosphate (TBP). The reagents used in scavenging 1 include 240 g / t of diesel oil and 240 g / t of TBP. The reagents used in scavenging 2 include 120 g / t of diesel oil and 120 g / t of TBP. The reagents used in cleaning 1 are 300 g / t of modified water glass, the reagents used in cleaning 2 are 200 g / t of modified water glass, and the reagents used in cleaning 3 are 100 g / t of modified water glass, thereby obtaining tin flotation concentrate and tin flotation tailings.

[0078] The results showed that for a feed containing 0.43% Sn and 0.11% WO3, a tin concentrate containing 1.10% Sn and 0.45% WO3 was obtained, with tin and tungsten recoveries of 9.70% and 10.50%, respectively. The significant decrease in tin and tungsten recovery rates was mainly due to the lack of significant collecting activity of diesel oil and TBP for tin and tungsten.

[0079] The above description of the embodiments is only for the purpose of helping to understand the technical solution and core idea of ​​the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A mineral processing technology for recovering tin from gravity separation tailings of iron-tin ore, characterized in that, Includes the following steps: S1. Hydrocyclone Classification: The tailings from the gravity separation of iron-tin ore are classified using hydrocyclones to obtain coarse and fine products. The hydrocyclone's underflow nozzle... The size is 50-100mm, the pressure is 0.1-0.3Mpa, and the classification efficiency of 0.074mm is 40%-60%. S2. Grading: The coarse-grained product from step S1 is graded to obtain three product grades: +0.3mm, -0.3+0.074mm, and -0.074mm. S3. Grinding: Grind the +0.3mm particle size product from step S2 to obtain the ground product; S4. Concentration: Combine and concentrate the fine-particle product from step S1 and the -0.074mm product from step S2 to obtain overflow water and sediment. S5. Weak magnetic separation: Weak magnetic separation is performed on the grinding product of step S3 and the sand in S4 to obtain iron concentrate and iron tailings. S6. Desulfurization and arsenic flotation: The sulfur tailings from step S5 are subjected to desulfurization and arsenic removal flotation to obtain sulfur-arsenic concentrate and sulfur-arsenic tailings. S7, Tin flotation: The sulfur and arsenic tailings from step S6 are subjected to tin flotation to obtain tin flotation concentrate and tin flotation tailings; S8. Reverse flotation to remove impurities: The tin flotation concentrate from step S7 is subjected to reverse flotation to remove impurities, thereby obtaining tin concentrate and arsenic concentrate.

2. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1, characterized in that, The iron-tin ore gravity separation tailings mentioned in step S1 are the tailings after iron-tin ore has undergone magnetic separation of iron, flotation of zinc, and gravity separation of tin, containing Sn 0.3%–0.5%, WO3 0.05%–0.15%, TFe 15%–20%, mFe 0.1%–0.8%, S 0.3%–0.8%, and As 0.5%–1.5%.

3. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1 or 2, characterized in that, In step S2, the coarse particles are graded using a high-frequency sieve. The high-frequency sieve is double-layered, with Sn content ranging from -0.074mm particle size to +0.3mm particle size to -0.3mm and +0.074mm particle size.

4. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1 or 2, characterized in that, In step S3, 60% to 80% of the grinding product has a grinding fineness of -0.074 mm.

5. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1 or 2, characterized in that, The concentration of the sediment in step S4 is 25% to 40%, and the solid content of the overflow water is <0.5%.

6. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1 or 2, characterized in that, The magnetic field strength for the weak magnetic separation in step S5 is 1500-3000 GS.

7. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1 or 2, characterized in that, The desulfurization and arsenic removal flotation in step S6 adopts a closed-circuit flotation process of 1 roughing, 1 scavenging, and 1 cleaning. The reagents added for roughing include 50-100 g / t of copper sulfate, 100-200 g / t of pentyl xanthate, and 30-50 g / t of monohydric alcohol. The reagents added for scavenging are 50-100 g / t of pentyl xanthate. No reagents are added for cleaning.

8. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1 or 2, characterized in that, The tin flotation described in step S7 adopts a closed-circuit flotation process of 1 roughing, 2 scavenging, and 3 cleaning. The reagents added in the roughing stage include 300-600 g / t of lead nitrate, 500-1000 g / t of benzohydroxyxamic acid, 50-100 g / t of diesel oil, and 50-100 g / t of tributyl phosphate. The reagents added in scavenging stage 1 include 200-400 g / t of GYB, 30-60 g / t of diesel oil, and 30-60 g / t of TBP. The reagents added in scavenging stage 2 include 100-200 g / t of GYB, 20-40 g / t of diesel oil, and 20-40 g / t of TBP. The reagents added in cleaning stage 1 are 200-300 g / t of water glass, the reagents added in cleaning stage 2 are 100-200 g / t of water glass, and the reagents added in cleaning stage 3 are 50-100 g / t of water glass.

9. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1 or 2, characterized in that, The reverse flotation impurity removal in step S8 adopts an open-circuit flotation process that combines 1 rougher and 2 concentrate tailings. The reagents added to the rougher include 1000-2000 g / t of sulfuric acid and 10-20 g / t of monohydric alcohol, while no reagents are added to the concentrate.

10. The mineral processing technology for recovering tin from iron-tin ore gravity separation tailings according to claim 1 or 2, characterized in that, Steps S5-S8 yield tin concentrate, iron concentrate, sulfur-arsenic concentrate, and arsenic concentrate. The tin concentrate contains 10%–30% Sn and 5%–10% WO3, with a Sn recovery rate of 40%–60% and a WO3 recovery rate of 50%–70%. The iron concentrate is mainly composed of magnetite, the sulfur-arsenic concentrate is mainly composed of pyrite and arsenopyrite, and the arsenic concentrate is mainly composed of orthorhombic arsenopyrite.

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