Iron lithium mica collector, method for efficient comprehensive recovery of low-grade lithium tungsten tin polymetallic ore

Abstract

The present invention discloses a new method for the efficient and comprehensive recovery of low-grade lithium-tungsten-tin polymetallic ores using a ferro-lepidolite collector. The method comprises: pre-grading and re-grinding of the raw ore; wet grading; re-selection to recover tungsten and tin; weak magnetic impurity removal; strong magnetic separation of weak magnetic tailings; flotation of strong magnetic concentrate; wet grading of strong magnetic tailings; and flotation of -0.038mm particle size strong magnetic tailings. The raw ore of the present invention is pre-graded and re-grinded to reduce over-crushing of tungsten and tin; grading + chute + shaking table re-selection is used, which reduces the chute footprint and reduces the shaking table processing capacity; strong magnetic + flotation recovery of lithium has good process resistance to mud, low reagent cost, and higher lithium grade and recovery rate; and the strong magnetic tailings are further recovered through fine-particle enhanced flotation, which helps to improve the total Li2O recovery rate. The present invention can achieve a Li2O grade of ≥2.0% in the iron lithium mica concentrate when the Li2O grade in the raw ore is 0.25-0.6%, and a total Li2O recovery rate of ≥87%, and can also realize the comprehensive recovery of associated tungsten and tin.

Description

Technical Field

[0001] The present invention belongs to the technical field of mineral processing, and in particular relates to a method for efficiently and comprehensively recovering a ferrolithium mica collector and low-grade lithium-tungsten-tin polymetallic ore. Background Art

[0002] Lithium, hailed as the "new energy of the 21st century" and the "metal that propels the world forward," is a scarce, clean resource widely used in numerous fields, including lithium batteries, the nuclear industry, and solid fuels. As lithium demand continues to grow, extracting lithium from spodumene alone is no longer sufficient to meet market demand. Lepidolite, a lithium-containing mineral with relatively large reserves in my country, is one of the most important resources for lithium extraction. With the increasing mining and utilization of single lepidolite deposits, this rich mineral is becoming increasingly scarce. Therefore, enhancing the recovery of complex, low-grade, lithium-bearing polymetallic ores is another effective way to increase lithium resource utilization.

[0003] The main elements that can be recovered from complex low-grade lithium-containing polymetallic ores are generally lithium, tungsten, and tin. Tin mainly exists in the form of cassiterite, and tungsten mainly exists in the form of scheelite and wolframite. Lithium oxide accounts for the largest proportion in mica. The target minerals in the mineral composition are mainly ferrolithium mica, as well as lepidolite, wolframite, scheelite, and cassiterite. The gangue minerals are mainly feldspar and quartz. The selection of this type of lithium-containing polymetallic ores has the following difficulties: (1) The mineral composition and its intercalation relationship are complex. Ferrolithium mica and other materials are layered silicate minerals containing lithium elements. They are elastic and flake-like and difficult to be ground. Fine grinding is required to achieve monomer dissociation. Ferrolithium mica and other materials and feldspar / quartz are prone to mudification (particle size <20μm). Among them, after the ferrolithium mica and other materials are mudified, they are difficult to recover by conventional flotation and magnetic separation, which can easily cause serious loss of lithium metal. However, the mudification of feldspar / quartz can easily cause the flotation environment of ferrolithium mica to deteriorate; (2) Tungsten-tin minerals are of high value, brittle and easy to mud. The selection of grinding fineness for such polymetallic ores needs to take into account the comprehensive recovery of tungsten and tin and the sufficient monomer dissociation of ferrolithium mica; (3) Due to the similar crystal structure and chemical properties of silicate minerals such as ferrolithium mica, feldspar, and quartz, and their low grades, it is difficult to obtain efficient separation and enrichment of ferrolithium mica.

[0004] In summary, it is urgent to develop new methods for efficient separation of such low-grade lithium polymetallic ores, which is of great significance to improving the utilization rate of lithium, tungsten and tin metal resources. Summary of the Invention

[0005] The purpose of the present invention is to address the difficulties in selecting low-grade lithium-tungsten-tin polymetallic ores and provide a new collector for lithophile mica and a method for efficient comprehensive recovery of low-grade lithium-tungsten-tin polymetallic ores. The present invention is used to solve the problems of low tungsten-tin recovery rate, difficulty in separating lithophile mica from feldspar / quartz, and serious loss of fine-grained lithophile mica under traditional process and reagent conditions in the flotation system of such ores. Ultimately, the effective enrichment of lithophile mica and the enhanced recovery of fine-grained lithium are achieved, while the recovery rate of associated tungsten and tin metals is improved.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention first provides a lepidolite collector LC-1, which is based on the total mass of its active components. The active components are composed of the following mass percentages: 5-20% of a cationic collector A, 45-50% of an anionic collector B, and the balance of an anionic collector C; the cationic collector A is composed of dodecylamine and isopropyl alcohol in a mass ratio of (5-3):1; the anionic collector B is saponified oleic acid; the anionic collector C is composed of sodium dodecylsulfonate, C 12-14 The fatty alcohol polyoxyethylene ether is composed in a mass ratio of 1:(1-2).

[0008] The mass concentration of the active component in the lithophile mica collector LC-1 is 5-10%.

[0009] The method of using the iron lithium mica collector LC-1 is as follows: during the flotation process, the cationic collector A, the anionic collector B, and the anionic collector C are first prepared into solutions with a mass concentration of 5-10%, and then added to the ore pulp at the same time.

[0010] The present invention also provides a fine-grained lithium iron mica collector LC-2, which is based on the total mass of its active components, and its active components are composed of the following mass percentages: 10-35% of cationic collector D, 10-50% of anionic collector B, and 20-65% of anionic collector C; the cationic collector D is composed of dodecylamine, isopropyl alcohol, kerosene and carboxymethyl cellulose in a mass ratio of (11-9):(2-4):(2-4):1; the anionic collector B is saponified oleic acid; the anionic collector C is composed of sodium dodecylsulfonate, C 12-14 The fatty alcohol polyoxyethylene ether is composed in a mass ratio of 1:(1-2).

[0011] The mass concentration of the active component in the fine-grained lithophile mica collector LC-2 is 5-10%.

[0012] The method of using the fine-grained iron lithium mica collector LC-2 is as follows: during the flotation process, the cationic collector D, the anionic collector B, and the anionic collector C are first prepared into solutions with a mass concentration of 5-10%, and then added to the ore pulp at the same time.

[0013] The present invention also provides a method for efficient and comprehensive recovery of low-grade lithium-tungsten-tin polymetallic ore, comprising the following steps:

[0014] 1) Pre-classification of the ore followed by grinding: The crushed ore is pre-classified using a sieve with a sieve aperture of 0.074 mm to obtain a +0.074 mm particle size ore sample and a -0.074 mm particle size ore sample; the +0.074 mm particle size ore sample is then wet ball milled to obtain a ground ore pulp; the ground ore pulp and the -0.074 mm particle size ore sample are then combined as the selected ore pulp;

[0015] 2) Wet classification: The raw ore slurry obtained in step 1) is wet classified to be divided into +0.074 mm particle size ore sample, -0.074+0.038 mm particle size ore sample and -0.038 mm particle size ore sample;

[0016] 3) Recycling tungsten and tin by gravity separation: The three particle size ore samples obtained in step 2) are subjected to chute + shaking table gravity separation to obtain tungsten-tin concentrates, gravity separation ore, and gravity separation tailings of three particle sizes respectively; the tungsten-tin concentrates of the three particle sizes are combined to obtain tungsten-tin concentrate;

[0017] 4) Weak magnetic impurity removal: The gravity separation ore and gravity separation tailings of the three particle sizes obtained in step 3) are combined as the iron lithium mica separation feed, and weak magnetic separation and impurity removal are performed to obtain weak magnetic concentrate and weak magnetic tailings;

[0018] 5) Strong magnetic separation of weak magnetic tailings: strong magnetic separation is performed on weak magnetic tailings to obtain strong magnetic concentrate and strong magnetic tailings;

[0019] 6) Flotation of strong magnetic concentrate: adding a gangue inhibitor and the lepidolite collector LC-1 to the strong magnetic concentrate, respectively, to carry out flotation of the lepidolite to obtain a lepidolite concentrate 1 and a flotation tailing 1;

[0020] 7) Wet classification of strong magnetic tailings: The strong magnetic tailings are wet classified into +0.038mm particle size strong magnetic tailings and -0.038mm particle size strong magnetic tailings;

[0021] 8) Flotation of -0.038 mm particle size strong magnetic tailings: Add a regulator, an inhibitor, and a fine-grained lithodactyl collector LC-2 to the -0.038 mm particle size strong magnetic tailings in step 7) to perform enhanced flotation of the fine-grained lithodactyl, thereby obtaining lithodactyl concentrate 2 and flotation tailings 2.

[0022] Preferably, in step 1), the +0.074 mm particle size ore sample is wet ball milled and combined with the -0.074 mm particle size ore sample, and the fineness of the combined ore is -0.074 mm, accounting for 40-65%.

[0023] Preferably, in step 3), the tungsten-tin regeneration process is carried out by combining a spiral chute and a shaking table, and the process is chute roughing - chute middling scavenging - chute concentrate shaking table roughing - shaking table cleaning; taking one of the ore samples with a particle size of +0.074mm as an example, the specific process includes the following steps:

[0024] ① Roughing chute: Roughing is performed on the +0.074mm particle size ore sample to obtain chute fine 1, chute middle 1 and chute tail 1;

[0025] ② Chute scavenging: Feed the chute middle 1 obtained in ① into the chute for scavenging to obtain chute fine 2, chute middle 2 and chute tail 2;

[0026] ③ Shaking table roughing: The chute concentrate 1 obtained in ① and the chute concentrate 2 obtained in ② are combined and fed into the shaking table for fine selection to obtain shaking table concentrate 1, shaking table middle 1 and shaking table tail 1 respectively;

[0027] ④ Shaker selection: Shaker concentrate 1 obtained in ③ is further subjected to shaker selection to obtain shaker concentrate 2, shaker middle 2 and shaker tail 2;

[0028] The obtained chute tail 1, chute tail 2, shaking table tail 1, and shaking table tail 2 are combined into gravity separation tailings; the obtained chute middle 2, shaking table middle 1, and shaking table middle 2 are combined into gravity separation ore; the obtained shaking table concentrate 2 is +0.074mm tungsten-tin concentrate;

[0029] The process is adopted to re-select the -0.074+0.038mm particle size ore sample and the -0.038mm particle size ore sample, respectively, to obtain the -0.074+0.038mm particle size ore, the re-selection tailings and the tungsten-tin concentrate, and similarly to obtain the -0.038mm particle size ore, the re-selection tailings and the tungsten-tin concentrate;

[0030] The obtained +0.074mm tungsten-tin concentrate, -0.074+0.038mm tungsten-tin concentrate and -0.038mm tungsten-tin concentrate are combined to obtain the final tungsten-tin concentrate;

[0031] The gravity separation ore and gravity separation tailings obtained by gravity separation of +0.074mm particle size, -0.074+0.038mm particle size and -0.038mm particle size are combined as the feed for iron lithium mica separation.

[0032] Preferably, in step 4), the weak magnetic separation and impurity removal adopts a primary roughing process with a magnetic field strength of 0.3 to 0.4 T.

[0033] Preferably, in step 5), the strong magnetic separation adopts a one-time roughing and two-time scavenging process, and the specific conditions include: the roughing magnetic field strength is 1.0-1.5T, and the impulse frequency is 50-250r / min; the first scavenging magnetic field strength is 1.0-2.0T, and the impulse frequency is 0-150r / min; the second scavenging magnetic field strength is 1.0-2.0T, and the impulse frequency is 0-150r / min.

[0034] Preferably, in step 6), the active component of the gangue inhibitor is sodium hexametaphosphate.

[0035] More preferably, the gangue inhibitor is a sodium hexametaphosphate solution with a mass concentration of 3 to 5%.

[0036] Preferably, in step 6), the flotation process is one roughing process and two to four scavenging processes.

[0037] In some specific embodiments, in step 6), the flotation process is one roughing and four scavenging, comprising the following steps:

[0038] Primary roughing: add 100-500g / t of sodium hexametaphosphate to the strong magnetic concentrate, stir for 2-3 minutes, add 1200-500g / t of LC-, stir for 2-3 minutes, and flotate for 2-5 minutes to obtain roughing concentrate and roughing tailings;

[0039] Four scans:

[0040] Sweep 1: Add LC-1100-300g / t to the rougher tailings, stir for 2-3 minutes, and float for 1-5 minutes to obtain sweep 1 and sweep 1 tailings;

[0041] Scavenging 2: Add LC-150-300g / t to the scavenging 1 tailings, stir for 2-3 minutes, and float for 1-5 minutes to obtain scavenging concentrate 2 and scavenging 2 tailings;

[0042] Scavenging and selection 3: add LC-125~300g / t to the scavenging and selection 2 tailings, stir for 2~3min, float for 1~3min, and obtain scavenging concentrate 3 and scavenging and selection 3 tailings;

[0043] Scavenging 4: Add LC-125-150g / t to the scavenging 3 tailings, stir for 2-3 minutes, and float for 1-3 minutes to obtain scavenging concentrate 4 and flotation tailings 1;

[0044] The rougher concentrate, sweep concentrate 1, sweep concentrate 2, sweep concentrate 3 and sweep concentrate 4 are combined into iron lithium mica concentrate 1.

[0045] Preferably, in step 6), the stirring speed of the flotation machine during the flotation process is 1600-2000 r / min.

[0046] Preferably, in step 8), the active ingredient of the regulator is sodium carbonate.

[0047] Further preferably, the adjusting agent is a sodium carbonate solution with a mass concentration of 5 to 10%;

[0048] Preferably, in step 8), the active component of the gangue inhibitor is sodium hexametaphosphate;

[0049] More preferably, the gangue inhibitor is a sodium hexametaphosphate solution with a mass concentration of 3 to 5%.

[0050] Preferably, in step 8), the flotation process is a process of one roughing, three scavenging and two cleaning, comprising the following steps:

[0051] Primary roughing: first add 500-3000g / t of sodium carbonate to the -0.038mm particle size strong magnetic tailings, stir for 3-10 minutes, then add 200-2000g / t of sodium hexametaphosphate, stir for 2-3 minutes, then add 2500-4000g / t of LC-, stir for 5-10 minutes, and float for 2-6 minutes to obtain roughing concentrate and roughing tailings;

[0052] Three scans:

[0053] Sweep 1: first add 250-1500g / t of sodium carbonate to the rougher tailings, stir for 3-10 minutes, then add 100-1000g / t of sodium hexametaphosphate, stir for 2-3 minutes, then add 2250-2000g / t of LC-2, stir for 5-10 minutes, and float for 2-4 minutes to obtain sweep 1 and sweep 1 tailings;

[0054] Scavenging 2: Add LC-2100~500g / t to the scavenging 1 tailings, stir for 3~5min, and float for 1~5min to obtain scavenging concentrate 2 and scavenging 2 tailings;

[0055] Sweep 3: Add LC-2 100-500g / t to the scavenger 2 tailings, stir for 3-5 minutes, and float for 1-5 minutes to obtain scavenger concentrate 3 and flotation tailings 2; scavenger concentrate 1, scavenger concentrate 2, and scavenger concentrate 3 are returned to the previous operation in sequence;

[0056] Second selection:

[0057] Concentration 1: Blank concentration is performed on the rougher concentrate, and flotation is performed for 1 to 3 minutes to obtain concentrate 1 and middling 1;

[0058] Concentration 2: blank concentration is carried out on the concentrate of Concentration 1, and flotation is carried out for 1 to 3 minutes to obtain iron lithium mica concentrate 2 and middling 2;

[0059] All intermediate ores are returned to the previous level of operation in sequence.

[0060] Preferably, in step 8), the stirring speed of the flotation machine is 2000-2300 r / min.

[0061] In the present invention, g / t refers to the amount of each reagent added to 1 ton of raw ore.

[0062] Principle of the present invention:

[0063] The present invention adopts the process of "pre-classification of raw ore - grinding - classification - chute + shaking table gravity separation to recover tungsten and tin - weak magnetic impurity removal - strong magnetic separation + flotation to recover lithophile mica - strong magnetic tailings - 0.038mm particle size flotation to recover fine lithophile mica":

[0064] (1) In the present invention, the raw ore is pre-classified using a 0.074 mm particle size sieve, and the -0.074 mm particle size slurry is combined with the +0.074 mm grinding slurry to prevent fine particles in the raw ore from directly entering the mill for grinding, effectively preventing lithium tungsten tin from being over-crushed, and effectively reducing the processing capacity of the mill;

[0065] (2) The present invention adopts strong magnetic separation to initially enrich lithophile mica, thereby ensuring the recovery rate of Li2O in the concentrate, and effectively avoids the problems of muddy gangue interfering with the flotation of lithophile mica, large reagent consumption, and difficulty in improving the Li2O grade and recovery rate of the concentrate when adopting the full-process flotation scheme. At the same time, the strong magnetic concentrate is further flotated to improve the Li2O grade of the concentrate;

[0066] (3) Strengthen the recovery of fine-grained iron lithium mica from the 0.038mm particle size strong magnetic tailings, and improve the total recovery rate of Li2O in the whole process;

[0067] (4) The active components of the iron lithium mica collector LC-1 of the present invention are dodecylamine, isopropyl alcohol, saponified oleic acid, sodium dodecylsulfonate, C 12-14 It is composed of fatty alcohol polyoxyethylene ether. Dodecylamine is a cationic collector, but its solubility is low. Adding isopropyl alcohol will make the existence of dodecylamine mucus in the aqueous solution more uniform. At the same time, the alcohol reagent isopropyl alcohol is a defoaming agent, which can effectively improve the problems of foam stickiness and difficulty in merging during dodecylamine flotation. The foam is refreshing and there is less gangue entrainment. Oleic acid is saponified to improve its dispersibility and dispersion in the slurry. The molecules of dodecylamine, oleic acid and sodium dodecylsulfonate collectors are all composed of a hydrophilic head group and a hydrophobic tail chain. The head group of dodecylamine is a positively charged NH3 + The head group of oleic acid is COO - , the head group of sodium dodecylsulfonate is SO3 -. The polarity between the head groups of the cationic collector molecule dodecylamine and the anionic collectors oleic acid and sodium dodecylsulfonate is opposite. The strong hydrophobic effect between the tail chains and the strong electrostatic interaction between the head groups make the formed aggregates lower in energy and more stable. Therefore, the anionic-cationic combination collector will also show higher surface activity and be more easily adsorbed on the surface and interface. Its flotation performance is better than that of a single collector. At the same time, under the combined collector system, the head groups of different types of molecules attract each other, which reduces electrostatic repulsion and enhances the intermolecular association, resulting in larger and tighter aggregates. The addition of anionic collectors can adjust the sticky and difficult-to-break properties of dodecylamine foam and reduce the mechanical entrainment of gangue into the concentrate. The combined collector has both collection performance and selectivity. In the solid-liquid interface system, the adsorption of cationic dodecylamine dominates, primarily physically adsorbing on the surface of lithofeldite through electrostatic interactions, and chemically adsorbing on the surface through hydrogen bonding. Anionic oleic acid and sodium dodecylsulfonate co-adsorb on the surface of lithofeldite through electrostatic interactions with the dodecylamine head group, electrostatic interactions with the metal ions on the lithofeldite surface, and hydrophobic interactions with the dodecylamine tail chain. The intercalated adsorption of oleic acid and sodium dodecylsulfonate makes the collector adsorption film more compact and the lithofeldite surface more hydrophobic. Only a small amount of dodecylamine adsorbs on the quartz / feldspar surface, resulting in a low adsorption strength of the combined collector on the quartz / feldspar surface, which is beneficial for the selective separation of lithofeldite from gangue materials such as feldspar / quartz. 12-14 Fatty alcohol polyoxyethylene ether is a non-ionic surfactant with good acid and alkali resistance and low temperature resistance. It can promote the low-temperature solubility and dispersibility of anionic-cationic combined collectors, react more fully with minerals, and improve flotation foam.

[0068] (5) The active components of the fine-grained iron lithium mica collector LC-2 of the present invention are dodecylamine, isopropyl alcohol, kerosene, saponified oleic acid, sodium dodecylsulfonate, C 12-14The combination of fatty alcohol polyoxyethylene ether and carboxymethyl cellulose clearly demonstrates that in the flotation system for fine-grained lithodopsis mica, LC-2 adds non-polar kerosene and carboxymethyl cellulose to the reagent components of LC-1. During the reagent preparation process, dodecylamine and kerosene are first mixed to form a miscible collector. A portion of the dodecylamine acts as a collector and adsorbs on the surface of the lithodopsis mica, while the remaining portion acts as an emulsifier. Its non-polar hydrocarbon chain is inserted into the oil phase, and its polar group faces the water phase at the oil-water interface, thereby changing the zeta potential of the kerosene droplet surface from negative to positive. This change allows the kerosene droplets to interact with the lithodopsis mica surface through electrostatic adsorption, strengthening the adhesion process between the kerosene and the lithodopsis mica. The addition of kerosene, in particular, induces and promotes hydrophobic aggregation for fine-grained lithodopsis mica, enhancing the capture of fine particles. In a flotation system using LC-2 as a collector, the stirring speed of the flotation machine's agitator is increased from the conventional 1600-2000 r / min to 2000-2300 r / min. The fluid movement during agitation and slurry mixing causes hydrophobic aggregation of the fine-grained lithophile mica in the -0.038mm particle size of the magnetic tailings, increasing the particle size of the lithophile mica, thereby increasing its collision probability with bubbles and improving flotation recovery. Carboxymethyl cellulose, a green and efficient carbonate and silicate inhibitor, as a component of LC-2, can effectively improve its selectivity. It also acts as a defoamer, reducing the foam viscosity of the combined collector and resulting in a clearer flotation foam.

[0069] Beneficial effects of the present invention:

[0070] (1) For low-grade lithium-tungsten-tin polymetallic ores, the present invention not only recovers iron lithium mica, but also comprehensively recovers the low-grade associated metals tungsten and tin in the original ore. In the present invention: ① By pre-grading and re-grinding, compared with direct grinding, the over-crushing of tungsten, tin and lithium can be reduced, which is beneficial to subsequent recovery; ② The tungsten and tin grades in the original ore are low, and the gravity separation adopts a chute + shaking table combination. Compared with a single shaking table, the chute occupies a small area, which plays the role of pre-enrichment. By discarding the tailings with low tungsten and tin content, the processing capacity of the shaking table is reduced, and the chute concentrate is re-shaken to effectively improve the tungsten and tin grades; ③ The iron lithium mica is recovered by using a process of strong magnetic separation pre-enrichment - strong magnetic concentrate flotation of coarse iron lithium mica - strong magnetic tailings - 0.038mm flotation of fine iron lithium mica. Compared with the full flotation iron lithium mica process, magnetic separation plays the role of enriching mud, avoiding the loss of Li2O caused by desludging in the full process flotation scheme, and no reagent consumption. Magnetic separation concentrate re-flotation is more conducive to obtaining high-grade iron lithium mica concentrate products. In order to recover the fine iron lithium mica in the 0.038mm particle size in the magnetic separation tailings, the concept of enhanced fine particle hydrophobic agglomeration flotation is adopted to achieve enhanced recovery of fine iron lithium mica in the tailings and improve the total recovery rate of Li2O.

[0071] (2) In the present invention, dodecylamine, isopropyl alcohol, saponified oleic acid, sodium lauryl sulfonate, C12-14 Fatty alcohol polyoxyethylene ether is combined into the active ingredient of collector LC-1. LC-1 is used to float lithophile mica under neutral slurry conditions (pH = 7). Compared with conventional strongly acidic slurry conditions (pH = 2-3), using a single dodecylamine as a collector effectively avoids problems such as harsh operating environment, high equipment corrosion protection requirements, and difficulty in wastewater reuse. Furthermore, LC-1 is an anionic-cationic combined collector. Compared with a single dodecylamine cationic collector, LC-1 is simpler to prepare, has a faster flotation rate, and produces a clear, non-sticky flotation foam that is easier to merge, with less gangue entrainment, good foam fluidity, and easy industrial operation.

[0072] (3) In the present invention, the composition comprises dodecylamine, isopropyl alcohol, kerosene, saponified oleic acid, sodium lauryl sulfonate, C 12-14 Fatty alcohol polyoxyethylene ether and carboxymethyl cellulose are combined as the active ingredients of the collector LC-2. By adding non-polar kerosene, a miscible system of dodecylamine, non-polar oil, surfactant, and modifier is formed. The addition of LC-2 increases the hydrophobic interaction of the lithophile mica, eliminates the energy barrier between particles, and causes hydrophobic aggregation between the fine lithophile mica particles. This increases the particle size, thereby increasing the collision rate between the particles and the bubbles and improving the total Li2O recovery rate.

[0073] (4) Aiming at the separation of low-grade lithium-tungsten-tin polymetallic ores, the present invention provides a combined process of gravity separation, magnetic separation and flotation, using new iron-lithium mica collectors LC-1 and LC-2. When the Li2O grade in the raw ore is 0.25-0.60%, the good indicators of Li2O grade ≥2.0% and total Li2O recovery rate ≥87% in the iron-lithium mica concentrate are obtained, and the comprehensive recovery of associated tungsten and tin can be achieved at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 This is the process flow of Example 1 and Comparative Examples 4 to 8;

[0075] Figure 2 This is the process flow of Comparative Example 2;

[0076] Figure 3 This is the process flow of Comparative Examples 3 and 9;

[0077] Figure 4 This is the process flow of Example 2 and Comparative Examples 11-12;

[0078] Figure 5 This is the process flow of Comparative Example 10. DETAILED DESCRIPTION

[0079] In the following examples and comparative examples, all the drugs used can be purchased from commercial sources.

[0080] The ore used in Example 1 and Comparative Examples 1-8 is a low-grade lithium-tungsten-tin polymetallic ore in Jiangxi Province. The primary elements recoverable from the ore are lithium, tin, and tungsten, with grades of 0.55%, 0.06%, and 0.08%, respectively. Other valuable elements are relatively low in content, making their comprehensive recovery value low. The components that require separation include SiO₂, Al₂O₃, and K₂O. The primary target minerals that can be recovered are lepidolite, lepidolite, wolframite, and cassiterite. The primary gangue minerals are quartz and feldspar. Lepidolite is primarily associated with gangue minerals such as quartz and feldspar, primarily in a simple adjacent formation, with a small percentage being encapsulated.

[0081] The specific configuration and use of the iron lithium mica collector LC-1 used in Example 1 and Comparative Examples 1-2 are as follows:

[0082] Heat and dissolve dodecylamine, weigh isopropyl alcohol and add it, the mass ratio of dodecylamine to isopropyl alcohol is 3:1, stir and dissolve to form cationic collector A-1; saponify oleic acid according to the mass ratio of oleic acid to sodium hydroxide solids of 5:1, add hot water at a temperature of 80°C, stir continuously, and saponify for 30 minutes. After the saponification is complete, saponified oleic acid, i.e., anionic collector B-1, is obtained; sodium dodecyl sulfate and C 12-14 Fatty alcohol polyoxyethylene ethers were mixed in a mass ratio of 1:1.5 to form anionic collector C-1; then collectors A-1, B-1 and C-1 were respectively prepared into solutions with a mass concentration of 5%, and then added to the slurry at the same time in a mass percentage of 14%:45%:41%.

[0083] The specific configuration and use of the fine-grained lithium iron mica collector LC-2 used in Example 1 are as follows:

[0084] According to the solid mass ratio of oleic acid to sodium hydroxide of 6.5:1, add hot water at 80℃, stir continuously, and saponify for 30 minutes. After completion, saponified oleic acid, i.e., anionic collector B-2, is obtained. Sodium dodecyl sulfate and C 12-14 Fatty alcohol polyoxyethylene ethers are mixed in a mass ratio of 1:1.7 to obtain an anionic collector C-2; dodecylamine is heated and dissolved, isopropyl alcohol and kerosene are weighed and added thereto, water is added and stirred, and then carboxymethyl cellulose is added and continuously stirred and dissolved, wherein the mass ratio of dodecylamine, isopropyl alcohol, kerosene and carboxymethyl cellulose is 11:2:2:1, and mixed to obtain a stock solution containing a cationic collector D-1; collectors D-1, B-2 and C-2 are first prepared into a solution with a mass concentration of 5%, and then added to the ore pulp at the same time in a mass percentage of 25%:20%:55%.

[0085] In Example 1 and Comparative Examples 1-2, 4-8, sodium hexametaphosphate and the adjusting agent sodium carbonate were added to the ore pulp in the form of aqueous solutions prepared to have a mass concentration of 5%.

[0086] Example 1

[0087] The combined process of "pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal - strong magnetic separation + flotation to recover ferrolithium mica - strong magnetic tailings - 0.038mm particle size flotation to recover fine ferrolithium mica" is adopted to obtain tungsten and tin concentrate and ferrolithium mica concentrate respectively. The experimental process and reagent system are as follows: Figure 1 The specific steps are as follows:

[0088] 1) The raw ore sample is first crushed and then pre-classified using a sieve with a sieve aperture of 0.074 mm to obtain a +0.074 mm ore sample and a -0.074 mm ore sample; the +0.074 mm ore sample is then wet-ball milled to obtain a ground slurry; the ground slurry and the -0.074 mm ore sample are then combined as the selected raw ore slurry, and the fineness of the combined selected raw ore is -0.074 mm, accounting for 50%.

[0089] 2) Classification: Use 0.074mm and 0.038mm sieves to separate the selected raw ore pulp into +0.074mm particle size ore samples, -0.074+0.038mm particle size ore samples and -0.038mm particle size ore samples;

[0090] 3) Recycling tungsten and tin by gravity separation: The three particle size samples obtained by classification are fed into the chute + shaking table respectively, and the separation is carried out by chute roughing - chute middling scavenging - chute concentrate shaking table roughing - shaking table cleaning. The +0.074mm particle size sample is used as an example to illustrate the following steps:

[0091] ① Roughing chute: Roughing is performed on the +0.074mm particle size ore sample to obtain chute fine 1, chute middle 1 and chute tail 1;

[0092] ② Chute scavenging: Feed the chute middle 1 obtained in ① into the chute for scavenging to obtain chute fine 2, chute middle 2 and chute tail 2;

[0093] ③ Shaking table roughing: The chute concentrate 1 obtained in ① and the chute concentrate 2 obtained in ② are combined and fed into the shaking table for fine selection to obtain shaking table concentrate 1, shaking table middle 1 and shaking table tail 1 respectively;

[0094] ④ Shaking table selection: Shaking table concentrate 1 obtained in ③ is further shaken to obtain shaking table concentrate 2, shaking table middle 2 and shaking table tail 2; shaking table concentrate 2 is +0.074mm tungsten-tin concentrate;

[0095] The same process as above was adopted to reselect the -0.074+0.038mm particle size ore sample and the -0.038mm particle size ore sample respectively, and the tungsten-tin concentrate of -0.074+0.038mm at chute tail 1, chute middle 2, chute tail 2, shaking table middle 1, shaking table tail 1, shaking table middle 2, shaking table tail 2 and -0.074+0.038mm was obtained, and the tungsten-tin concentrate of -0.038mm at chute tail 1, chute middle 2, chute tail 2, shaking table middle 1, shaking table tail 1, shaking table middle 2, shaking table tail 2 and -0.038mm was obtained respectively;

[0096] +0.074mm tungsten-tin concentrate, -0.074+0.038mm tungsten-tin concentrate, and -0.038mm tungsten-tin concentrate are combined to obtain tungsten-tin concentrate;

[0097] 4) Weak magnetic impurity removal: The three particle sizes of chute tail 1, chute middle 2, chute tail 2, shaking table middle 1, shaking table tail 1, shaking table middle 2, and shaking table tail 2 obtained in step 3) are combined as iron lithium mica separation feed and subjected to weak magnetic separation and iron removal. The magnetic field strength is 0.3T to obtain weak magnetic concentrate and weak magnetic tailings.

[0098] 5) Strong magnetic separation of weak magnetic tailings: The weak magnetic tailings are subjected to strong magnetic separation, with one roughing separation and two scavenging separations. The roughing magnetic field strength is 1.0T, the pulsating impulse is 100r / min, the scavenging magnetic field strength is 1.3T, the pulsating impulse is 0r / min, and the scavenging magnetic field strength is 1.5T, the pulsating impulse is 0r / min, to obtain strong magnetic rough concentrate, strong magnetic scavenging concentrate 1, strong magnetic scavenging concentrate 2 and strong magnetic tailings; the strong magnetic rough concentrate, strong magnetic scavenging concentrate 1 and strong magnetic scavenging concentrate 2 are combined into strong magnetic concentrate;

[0099] 6) Flotation of strong magnetic concentrate: The flotation process of strong magnetic concentrate is one roughing and three scavenging. The stirring speed of the flotation machine is 1992r / min, and it includes the following steps:

[0100] Primary roughing: add 150g / t of sodium hexametaphosphate to the strong magnetic concentrate, stir for 2 minutes, add 1350g / t of LC-, stir for 3 minutes, and flotation for 3 minutes to obtain rough concentrate and roughing tailings;

[0101] Three scavenging processes: Scavenging 1: add LC-1200g / t to the rougher tailings, stir for 3 minutes, float for 2.5 minutes to obtain scavenging concentrate 1 and scavenging concentrate 1 tailings; Scavenging 2: add LC-1150g / t to the scavenging concentrate 1 tailings, stir for 3 minutes, float for 2 minutes to obtain scavenging concentrate 2 and scavenging concentrate 2 tailings; Scavenging 3: add LC-1100g / t to the scavenging concentrate 2 tailings, stir for 3 minutes, float for 1.5 minutes to obtain scavenging concentrate 3 and flotation tailing 1;

[0102] The coarse concentrate, sweep concentrate 1, sweep concentrate 2 and sweep concentrate 3 are combined into iron lithium mica concentrate 1.

[0103] 7) Strong magnetic tailings classification: The strong magnetic tailings obtained in step 5) are subjected to wet classification and divided into two particle sizes, +0.038 mm strong magnetic tailings and -0.038 mm strong magnetic tailings;

[0104] 8) -0.038mm strong magnetic tailings flotation: -0.038mm strong magnetic tailings flotation process is one roughing selection, three scavenging selection and two cleaning selection. The flotation machine stirring speed is 2112r / min, including the following steps:

[0105] Primary roughing: add 1000g / t of sodium carbonate to the -0.038mm strong magnetic tailings, stir for 5 minutes, add 300g / t of sodium hexametaphosphate, stir for 3 minutes, add 2500g / t of LC-, stir for 5 minutes, and flotation for 4 minutes to obtain roughing concentrate and roughing tailings;

[0106] Three scavenging processes: Scavenging 1: add 400g / t of sodium carbonate to the rougher tailings, stir for 8min, 250g / t of sodium hexametaphosphate, stir for 3min, add LC-2300g / t, stir for 5min, float for 2.5min to obtain scavenging concentrate 1 and scavenging concentrate 1 tailings; Scavenging 2: add LC-2200g / t to the scavenging concentrate 1 tailings, stir for 3min, float for 2min to obtain scavenging concentrate 2 and scavenging concentrate 2 tailings; Scavenging 3: add LC-2200g / t to the scavenging concentrate 2 tailings, stir for 3min, float for 1.5min to obtain scavenging concentrate 3 and flotation tailing 2;

[0107] Secondary concentration: Concentration 1: The roughing concentrate is subjected to blank concentration and flotation for 3 minutes to obtain concentrate 1 and middling 1; Concentration 2: The concentrate 1 is subjected to blank concentration and flotation for 2 minutes to obtain iron / lepidolite concentrate 2 and middling 2; all middlings are returned to the previous level operation in sequence.

[0108] The process of Example 1 is as follows Figure 1 The test results are shown in Tables 1 and 2.

[0109] Comparative Example 1

[0110] This comparative example adopts the process of "pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal - full flotation of ferrolithium mica". The process of pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal is the same as that of Example 1, except that the ferrolithium mica separation adopts the full-process flotation process (without desludging). The weak magnetic tailings obtained after weak magnetic impurity removal are used as the ferrolithium mica feed ore for the full-process flotation operation. The specific steps are as follows:

[0111] Three roughing operations: Roughing 1: add 300 g / t of sodium hexametaphosphate to the weak magnetic tailings, stir for 2 minutes, add LC-1350 g / t, stir for 3 minutes, and flotate for 3.5 minutes to obtain a roughing concentrate and a roughing tailing; Roughing 2: add 150 g / t of sodium hexametaphosphate to the roughing tailings, stir for 2 minutes, add LC-1300 g / t, stir for 3 minutes, and flotate for 2.5 minutes to obtain a roughing concentrate and a roughing tailing; Roughing 3: add LC-1200 g / t to the roughing tailings, stir for 3 minutes, and flotate for 2 minutes to obtain a roughing concentrate and a roughing tailing;

[0112] Secondary scavenging: Scavenging 1: add LC-1100g / t to the rougher 3 tailings, stir for 3 minutes, float for 1.5 minutes, and obtain scavenging 1 concentrate (return to rougher 2) and scavenging 1 tailings;

[0113] Scavenging 2: Add LC-1100g / t to the tailings of scavenging 1, stir for 3 minutes, and float for 1 minute to obtain scavenging 2 concentrate (return to scavenging 1 operation) and tailings;

[0114] Secondary concentration: Selection 1: Blank selection, combine the rougher 1 concentrate, rougher 2 concentrate and rougher 3 concentrate for blank selection, flotation for 3 minutes, and obtain the selection 1 concentrate and medium 1 (return to rougher 2).

[0115] Selection 2: The concentrate of Selection 1 is subjected to blank selection and flotation for 2 minutes to obtain iron lithium mica concentrate and medium 2 (return to Selection 1 operation).

[0116] The test results are shown in Tables 1 and 2.

[0117] Comparative Example 2

[0118] This comparative example uses a process called "ore pre-classification - grinding - classification - tungsten-tin recovery by gravity separation - weak magnetic impurity removal - desliming of ferrolithium mica followed by flotation." The process flow of ore pre-classification, grinding - classification - tungsten-tin recovery by gravity separation - weak magnetic impurity removal is the same as that of Example 1, except that the ferrolithium mica separation uses a full-process flotation process (with desliming). The weak magnetic tailings obtained after weak magnetic impurity removal are first deslimed before flotation of the ferrolithium mica.

[0119] The weak magnetic tailings desludging operation adopts the siphon method, with a sedimentation time of 3 minutes and the fine mud is extracted.

[0120] The weak magnetic tailings after desliming are used to recover ferrolithium mica by flotation, using a process of one roughing, two sweeping and two refining, specifically as follows:

[0121] Primary roughing: add 150g / t of sodium hexametaphosphate to the deslimed weak magnetic tailings, stir for 2 minutes, add 1300g / t of LC-, stir for 3 minutes, and flotate for 3.5 minutes to obtain rough concentrate and roughing tailings;

[0122] Secondary scavenging: Scavenging 1: add LC-1200g / t to the roughing tailings, stir for 3 minutes, float for 1.5 minutes, and obtain scavenging 1 concentrate (return to the roughing operation) and scavenging 1 tailings; Scavenging 2: add LC-1100g / t to the scavenging 1 tailings, stir for 3 minutes, float for 1 minute, and obtain scavenging 2 concentrate (return to the scavenging 1 operation) and tailings;

[0123] Secondary selection: Selection 1: blank selection is performed on the coarse concentrate, and flotation is performed for 3 minutes to obtain the selected concentrate 1 and medium 1 (return to the rough selection); Selection 2: blank selection is performed on the selected concentrate 1, and flotation is performed for 2 minutes to obtain iron lithium mica concentrate and medium 2 (return to the selection operation 1).

[0124] The process of Comparative Example 2 is as follows Figure 2 The test results are shown in Tables 1 and 2.

[0125] Comparative Example 3

[0126] This comparative example adopts the process of "pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal - full magnetic separation of iron lepidolite". The process flow of pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal is the same as that of Example 1, except that the full process magnetic separation is adopted for iron lepidolite separation. The weak magnetic tailings obtained after weak magnetic impurity removal are subjected to full magnetic separation of iron lepidolite, and the specific steps are as follows:

[0127] The weak magnetic tailings are subjected to strong magnetic separation, roughing separation, scavenging separation and concentrating separation, and the concentrating middlings are then selected:

[0128] The magnetic field strength of the first roughing is 1.0T, the pulsating impulse is 100r / min, and a coarse concentrate is obtained; the magnetic field strength of the scavenging first is 1.3T, the pulsating impulse is 0r / min, and a scavenging concentrate 1 is obtained; the magnetic field strength of the scavenging second is 1.5T, the pulsating impulse is 0r / min, and a scavenging concentrate 2 and a strong magnetic tailing 1 are obtained; the coarse concentrate, scavenging concentrate 1 and scavenging concentrate 2 are combined into a strong magnetic coarse concentrate, and strong magnetic concentration is carried out, the magnetic field strength is 1.0T, the pulsating impulse is 100r / min, and iron lithium mica concentrate 1 and a concentrated middling are obtained; the concentrated middling is subjected to strong magnetic scavenging again, the magnetic field strength is 1.0T, the pulsating impulse is 100r / min, and a strong magnetic scavenging concentrate (returned to strong magnetic concentration) and a strong magnetic tailing 2 are obtained.

[0129] The test process of Comparative Example 3 is as follows Figure 3 , the test results are shown in Table 1 and Table 2.

[0130] Comparative Example 4

[0131] The whole process is basically the same as that of Example 1, except that the collector for lithium iron mica adopts single cationic collector A-1 (LC-1A); the collector for fine lithium iron mica adopts single cationic collector D-1 (LC-2D); the flotation process and flotation pulp conditions are the same as those of Example 1, but the flotation reagent is:

[0132] Strong magnetic concentrate flotation:

[0133] Roughing: LC-1A 350 g / t; Sweeping 1: LC-1A 200 g / t; Sweeping 2: LC-1A 150 g / t; Sweeping 3: LC-1A 100 g / t; other reagent systems remain unchanged.

[0134] -0.038mm strong magnetic tailings flotation:

[0135] Roughing: LC-2D 500g / t; Sweeping 1: LC-2D 300g / t; Sweeping 2: LC-2D 200g / t; Sweeping 3: LC-2D 200g / t; other reagent systems remain unchanged.

[0136] The process flow of comparative example 4 is as follows Figure 1 , the test results are shown in Table 1 and Table 2.

[0137] Comparative Example 5

[0138] The whole process is basically the same as that of Example 1, except that the iron lithium mica collector adopts the single anion collector B-1 (LC-1B), and the fine iron lithium mica collector adopts the single anion collector B-2 (LC-2B); the flotation process and flotation pulp conditions are the same as those of Example 1, but the flotation reagent is:

[0139] Strong magnetic concentrate flotation:

[0140] Roughing: LC-1B 350g / t; Sweeping 1: LC-1B 200g / t; Sweeping 2: LC-1B 150g / t; Sweeping 3: LC-1B 100g / t; other reagent systems remain unchanged.

[0141] -0.038mm strong magnetic tailings flotation:

[0142] Roughing: LC-2B 500g / t; Sweeping 1: LC-2B 300g / t; Sweeping 2: LC-2B 200g / t; Sweeping 3: LC-2B 200g / t; other chemical systems remain unchanged.

[0143] The process flow of comparative example 5 is as follows Figure 1 , the test results are shown in Table 1 and Table 2.

[0144] Comparative Example 6

[0145] The whole process is basically the same as that of Example 1, except that the iron lithium mica collector adopts a single anion collector C-1 (LC-1C); the fine iron lithium mica collector adopts a single anion collector C-2 (LC-2C); the flotation process and flotation pulp conditions are the same as those of Example 1, but the flotation reagent is:

[0146] Strong magnetic concentrate flotation:

[0147] Roughing: LC-1C 350g / t; Sweeping 1: LC-1C 200g / t; Sweeping 2: LC-1C 150g / t; Sweeping 3: LC-1C 100g / t; other reagent systems remain unchanged.

[0148] -0.038mm strong magnetic tailings flotation:

[0149] Roughing: LC-2C 500g / t; Sweeping 1: LC-2C 300g / t; Sweeping 2: LC-2C 200g / t; Sweeping 3: LC-2C 200g / t; other chemical systems remain unchanged.

[0150] The process flow of comparative example 6 is as follows Figure 1 , the test results are shown in Table 1 and Table 2.

[0151] Comparative Example 7

[0152] The whole process process is basically the same as that of Example 1, except that the iron lithium mica collector adopts a combination of cationic collector A-1 and anionic collector B-1 (LC-1AB), and the cationic collector A-1 and the anionic collector B-1 are respectively prepared into a solution with a mass concentration of 5%, and then added to the ore pulp at the same time in a mass percentage of 14%:86%.

[0153] The fine-grained iron lithium mica collector adopts a combination of cationic collector D-1 and anionic collector B-2 (LC-2DB). The cationic collector D-1 and the anionic collector B-2 are respectively prepared into a solution with a mass concentration of 5%, and then added to the slurry at the same time according to the mass percentage of 25%:75%.

[0154] The flotation process and flotation pulp conditions are the same as those in Example 1, but the flotation reagents are:

[0155] Strong magnetic concentrate flotation:

[0156] Roughing: LC-1AB 350g / t; Sweeping 1: LC-1AB 200g / t; Sweeping 2: LC-1AB 150g / t; Sweeping 3: LC-1AB 100g / t; other reagent systems remain unchanged.

[0157] -0.038mm strong magnetic tailings flotation:

[0158] Roughing: LC-2DB 500g / t; Sweeping 1: LC-2DB 300g / t; Sweeping 2: LC-2DB 200g / t; Sweeping 3: LC-2DB 200g / t; other reagent systems remain unchanged.

[0159] The process flow of comparative example 7 is as follows Figure 1 , the test results are shown in Table 1 and Table 2.

[0160] Comparative Example 8

[0161] The whole process process is basically the same as that of Example 1, except that the iron lithium mica collector adopts a combination of cationic collector A-1 and anionic collector C-1 (LC-1AC), and the collectors A-1 and C-1 are respectively prepared into a solution with a mass concentration of 5%, and then added to the slurry at the same time according to the mass percentage of 14%:86%.

[0162] The fine-grained iron lithium mica collector adopts a combination of cationic collector D-1 and anionic collector C-2 (LC-2DC). The collectors D-1 and C-2 are respectively prepared into a solution with a mass concentration of 5%, and then added to the slurry at the same time according to the mass percentage of 25%:75%.

[0163] The flotation process and flotation pulp conditions are the same as those in Example 1, but the flotation reagents are:

[0164] Strong magnetic concentrate flotation:

[0165] Roughing: LC-1AC 350g / t; Sweeping 1: LC-1AC 200g / t; Sweeping 2: LC-1AC 150g / t; Sweeping 3: LC-1AC 100g / t; other reagent systems remain unchanged.

[0166] -0.038mm strong magnetic tailings flotation:

[0167] Roughing: LC-2DC 500g / t; Scavenging 1: LC-2DC 300g / t; Scavenging 2: LC-2DC 200g / t; Scavenging 3: LC-2DC 200g / t; other reagent systems remain unchanged.

[0168] The process flow of comparative example 8 is as follows Figure 1 , the test results are shown in Table 1 and Table 2.

[0169] Table 1 Test results of tungsten and tin separation in Example 1 and Comparative Examples 1 to 8 / %

[0170]

[0171] Table 2 Comparative test results of lithium separation schemes in Example 1 and Comparative Examples 1 to 8 / %

[0172]

[0173]

[0174] As shown in Table 1, Example 1 and Comparative Examples 1 to 8 all employed the "ore pre-classification - grinding - classification - tungsten-tin recovery by gravity separation - weak magnetic iron removal" process, resulting in a tungsten-tin concentrate with a WO3 grade of 20.79%, a Sn grade of 18.56%, a WO3 recovery rate of 64.97%, and a Sn recovery rate of 74.84%. The Li2O loss rate in the tungsten-tin concentrate and weak magnetic concentrate was 0.25%. The Li2O grade in the ferrolithium mica feed ore was 0.56%, and the Li2O recovery rate was 99.75%, achieving efficient recovery of low-grade tungsten-tin, while also minimizing lithium loss in the tungsten-tin recovery process.

[0175] As shown in Table 2, (1) in Example 1, the recovery of lithium iron mica adopts the process of "strong magnetic pre-enrichment - strong magnetic concentrate flotation - strong magnetic tailings classification - -0.038mm particle size flotation to recover fine lithium iron mica", and the Li2O grade in the lithium iron mica concentrate 1 is 2.12%, and the Li2O operation recovery rate is 84.84%. The Li2O grade in the lithium iron mica concentrate 2 is 1.75%, and the Li2O operation recovery rate is 5.03%. The Li2O grade in the combined lithium iron mica concentrate is 2.10%, the Li2O operation recovery rate is 89.87%, and the total Li2O recovery rate is 89.65%; (2) in Comparative Example 1, the recovery of lithium iron mica adopts the process of "direct flotation without desliming", which is very Obviously, the flotation of lithium iron mica is greatly disturbed by the ore mud, and the Li2O grade in the lithium iron mica concentrate is 1.25%, and the Li2O recovery rate is only 65.05%; (3) In comparative example 2, the "flotation of lithium iron mica after desliming" process is adopted. Although the pre-desliming reduces the interference of the ore mud during the flotation of lithium iron mica, the Li2O grade in the lithium iron mica concentrate reaches 2.20%, but the Li2O loss rate in the mud concentrate is as high as 20.01%, and the Li2O recovery rate in the lithium iron mica concentrate is still relatively low, at 67.26%; (4) In comparative example 3, the full-process strong magnetic process is compared with the strong magnetic + flotation process in the embodiment. The concentrate of the strong magnetic process is seriously entrained, and the Li2O in the lithium iron mica concentrate is obtained. The grade of Li2O is 1.70%, and the recovery rate of Li2O is 80.83%. (5) In comparative example 4, the magnetic concentrate flotation adopts a single cationic collector A-1, and the fine particle flotation adopts a single cationic collector D-1, and the Li2O grade in the obtained iron lithium mica concentrate 1 is only 1.05%, and the sorting process lacks selectivity. In comparative examples 5-6, the magnetic concentrate flotation adopts a single anionic collector B-1 or C-1, and the fine particle flotation adopts a single anionic collector B-2 or C-2, and the recovery rate of Li2O in the iron lithium mica concentrate 1 is only 3.56% or 2.41%, and the recovery rate of Li2O in the iron lithium mica concentrate 2 is only 0.14% or 0.12%. %, indicating that under neutral pulp conditions, it is impossible to obtain qualified iron lithium mica concentrate products by using a single cationic collector or anionic collector; (6) In comparative examples 7-8, two of the three components are used, the magnetic concentrate flotation adopts a cationic and anionic collector combination AB or AC, and the fine particle flotation adopts a cationic and anionic collector combination DB or DC, and the iron lithium mica concentrate 1 is obtained with a Li2O grade of 1.42% or 1.70%, and a low Li2O recovery rate of 56.44% or 72.10% respectively; at the same time, the iron lithium mica concentrate 2 is obtained with a Li2O grade of 0.55% or 0.82%, and a Li2O recovery rate of 2.33% or 2.97% respectively.

[0176] Based on the above results, it can be seen that with respect to the comparison of the iron lithium mica separation process: compared with "direct flotation" (Comparative Example 1), "desliming-flotation" (Comparative Example 2) and "full process magnetic separation" (Comparative Example 3), the "strong magnetic-magnetic concentrate flotation-magnetic tailings recovery of fine particles" process (Example 1) in the present invention obtains the highest Li2O grade and total recovery rate in the combined iron lithium mica concentrate, with a Li2O grade of 2.10% and a Li2O total recovery rate of 89.87%. The combined magnetic separation and flotation separation process is less susceptible to ore mud interference, has low dressing agent costs, and produces clean flotation foam with good foam tension, making lithium easier to enrich and recover. ② Regarding the comparison of flotation agents for lithobite: Compared with single cationic collectors, single anionic collectors, and combinations of some anionic and cationic collectors, the present invention uses three-component combinations LC-1 and LC-2, respectively. The lithobite concentrate 1 has the highest Li2O grade of 2.12% and the highest Li2O recovery rate of 84.84%. The lithobite concentrate 2 also has the highest Li2O grade of 1.75%, with a Li2O recovery rate of 5.03%. This indicates that the anionic-anionic-cationic collector combination of the present invention is not simply a combination of different types of anionic and cationic collectors, but rather an interaction between specific components, interacting and influencing each other at the microscopic level between molecules and chemical bonds, thereby synergistically enhancing the Li2O grade and Li2O recovery rate.

[0177] The raw ore used in Example 2 and Comparative Examples 9 to 12 is a low-grade lithium-tungsten-tin polymetallic ore in Hunan. The main elements in the raw ore that can be recovered by beneficiation are lithium, tin, and tungsten, with grades of 0.37%, 0.040%, and 0.032%, respectively. The components that need to be removed from the ore for beneficiation are mainly SiO2, Al2O3, and K2O. The gangue minerals mainly include quartz, feldspar, chlorite, and calcite. Phase analysis shows that the ore has the largest proportion of lithium oxide in mica, followed by lithium in iron oxide, accounting for a total of 86.21%. Tin mainly exists in the form of cassiterite, accounting for 92.50%. Tungsten mainly exists in the form of wolframite, accounting for 62.50%, followed by scheelite, accounting for 32.25%. Cassiterite and tungsten minerals are embedded in medium and fine particles, while ferrolithium mica is embedded in continuous unequal particles. However, some mica particles are still small, especially the presence of sericite, which will be detrimental to mineral processing recovery and will also cause mudification during the mineral processing process, thus affecting the flotation effect.

[0178] The specific configuration and use of the iron lithium mica collector LC-1 used in Example 2 and Comparative Example 10 are as follows:

[0179] Heat and dissolve dodecylamine, weigh isopropyl alcohol and add it, the mass ratio of dodecylamine to isopropyl alcohol is 4:1, stir and dissolve to form cationic collector A-2; saponify oleic acid according to the mass ratio of oleic acid to sodium hydroxide solids of 6:1, add hot water at a temperature of 80°C, stir continuously, and saponify for 45 minutes. After the saponification is complete, saponified oleic acid, i.e., anionic collector B-3, is obtained; sodium dodecyl sulfate and C 12-14 Fatty alcohol polyoxyethylene ethers were mixed in a mass ratio of 1:2 to form anionic collector C-3; collectors A-2, B-3 and C-3 were respectively prepared into solutions with a mass concentration of 5%, and then added to the slurry at the same time in a mass percentage of 12%:45%:43%.

[0180] The specific configuration and use of the fine-grained lithium iron mica collector LC-2 used in Example 2 and Comparative Example 10 are as follows:

[0181] According to the solid mass ratio of oleic acid to sodium hydroxide of 5:1, add hot water at 80℃, stir continuously, and saponify for 45 minutes. After completion, saponified oleic acid, i.e., anionic collector B-4, is obtained; sodium dodecyl sulfate and C 12-14 Fatty alcohol polyoxyethylene ethers are mixed in a mass ratio of 1:1.5 to obtain an anionic collector C-4; dodecylamine is heated and dissolved, isopropyl alcohol and kerosene are weighed and added thereto, water is added and stirred, and then carboxymethyl cellulose is added and continuously stirred and dissolved, wherein the mass ratio of dodecylamine, isopropyl alcohol, kerosene and carboxymethyl cellulose is 10:3.5:3.5:1, and mixed to obtain a stock solution containing a cationic collector D-2; the cationic collector D-2 stock solution, collectors B-4 and C-4 are first prepared into a solution with a mass concentration of 5%, and then added to the ore pulp at the mass percentages of 20%:24%:56%.

[0182] In Example 2 and Comparative Examples 10 to 12, sodium hexametaphosphate was added to the slurry in the form of an aqueous solution prepared at a mass concentration of 5%; and the adjusting agent sodium carbonate was added to the slurry in the form of an aqueous solution prepared at a mass concentration of 8%.

[0183] Example 2

[0184] The combined process of ore pre-classification - grinding - classification - tungsten-tin recovery by gravity - weak magnetic iron removal - magnetic separation + flotation recovery of lithophile mica was adopted to obtain tungsten-tin concentrate and lithophile mica concentrate respectively. Figure 4 The specific steps are as follows:

[0185] 1) Ore pre-classification - grinding: The ore sample is first crushed and then pre-classified using a sieve with a sieve aperture of 0.074mm to obtain +0.074mm ore samples and -0.074mm ore samples; the +0.074mm ore samples are then wet-ball milled to obtain ground slurry; the ground slurry and the -0.074mm ore samples are then combined as the selected ore slurry, and the fineness of the combined selected ore is -0.074mm, accounting for 60%;

[0186] 2) Slurry classification after grinding: same as step 2) in Example 1;

[0187] 3) Recycling tungsten and tin by gravity: same as step 3 of Example 1;

[0188] 4) Weak magnetic impurity removal: basically the same as step 4) in Example 1, except that the magnetic field strength is 0.35 T;

[0189] 5) Strong magnetic separation of weak magnetic tailings: The weak magnetic tailings are subjected to strong magnetic separation, with one roughing separation and two scavenging separations. The roughing magnetic field strength is 1.3T, the pulsating impulse is 100r / min, the scavenging magnetic field strength is 1.5T, the pulsating impulse is 50r / min, and the scavenging magnetic field strength is 1.7T, the pulsating impulse is 50r / min, to obtain strong magnetic rough concentrate, strong magnetic scavenging concentrate 1, strong magnetic scavenging concentrate 2 and strong magnetic tailings; the strong magnetic rough concentrate, strong magnetic scavenging concentrate 1 and strong magnetic scavenging concentrate 2 are combined into strong magnetic concentrate;

[0190] 6) Flotation of strong magnetic concentrate: The flotation of strong magnetic concentrate is a roughing selection followed by a scavenging selection. The stirring speed of the flotation machine is 1992 r / min and includes the following steps:

[0191] Primary roughing: add 200g / t of sodium hexametaphosphate, a gangue inhibitor, to the strong magnetic concentrate, stir for 2 minutes, add LC-1300g / t, stir for 3 minutes, and flotate for 3 minutes to obtain rough concentrate and roughing tailings;

[0192] Secondary scanning:

[0193] Scavenging 1: add LC-1200g / t to the rougher tailings, stir for 3 minutes, float for 2.5 minutes to obtain scavenging concentrate 1 and scavenging 1 tailings; Scavenging 2: add LC-1150g / t to the scavenging 1 tailings, stir for 3 minutes, float for 2 minutes to obtain scavenging concentrate 2 and flotation tailings 1;

[0194] The coarse concentrate, sweep concentrate 1 and sweep concentrate 2 are combined into iron lithium mica concentrate 1.

[0195] 7) Strong magnetic tailings classification: same as step 7) in Example 1;

[0196] 8) Flotation of -0.038mm strong magnetic tailings: The flotation of -0.038mm strong magnetic tailings is a roughing selection, a scavenging selection and a cleaning selection. The stirring speed of the flotation machine is 2112r / min, including the following steps:

[0197] Primary roughing: add 800g / t of sodium carbonate as a regulator to the -0.038mm strong magnetic tailings, stir for 5 minutes, add 600g / t of sodium hexametaphosphate, stir for 2 minutes, add 2800g / t of LC-, stir for 8 minutes, and flotation for 4.5 minutes to obtain roughing concentrate and roughing tailings;

[0198] Three scavenging processes: Scavenging 1: add 300g / t of sodium carbonate to the rougher tailings, stir for 5 minutes, add 200g / t of sodium hexametaphosphate, stir for 2 minutes, add LC-2300g / t, stir for 5 minutes, float for 2 minutes to obtain scavenging concentrate 1 and scavenging concentrate 1 tailings; Scavenging 2: add LC-2200g / t to the scavenging concentrate 1 tailings, stir for 3 minutes, float for 2 minutes to obtain scavenging concentrate 2 and scavenging concentrate 2 tailings; Scavenging 3: add LC-2150g / t to the scavenging concentrate 2 tailings, stir for 3 minutes, float for 1.5 minutes to obtain scavenging concentrate 3 and flotation tailing 2;

[0199] Secondary concentration: Concentration 1: The roughing concentrate is subjected to blank concentration and flotation for 3 minutes to obtain concentrate 1 and middling 1; Concentration 2: The concentrate 1 is subjected to blank concentration and flotation for 2 minutes to obtain iron lithium mica concentrate 2 and middling 2; all middlings are returned to the previous level operation in sequence.

[0200] The test results are shown in Tables 3 and 4.

[0201] Comparative Example 9

[0202] This comparative example adopts the process of "pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal - full magnetic separation of iron lepidolite". The process flow of pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal is the same as that of Example 2, except that the full process magnetic separation is adopted for iron lepidolite separation. The weak magnetic tailings obtained after weak magnetic impurity removal are subjected to full magnetic separation of iron lepidolite, and the specific steps are as follows:

[0203] The weak magnetic tailings are subjected to strong magnetic separation, roughing separation, scavenging separation and concentrating separation, and the concentrating middlings are then selected:

[0204] The magnetic field strength of the first roughing is 1.5T, the pulsating impulse is 150r / min, and a coarse concentrate is obtained; the magnetic field strength of the first scavenging is 1.7T, the pulsating impulse is 0r / min, and a scavenging concentrate 1 is obtained; the magnetic field strength of the second scavenging is 1.7T, the pulsating impulse is 0r / min, and a scavenging concentrate 2 and a strong magnetic tailing 1 are obtained; the coarse concentrate, scavenging concentrate 1 and scavenging concentrate 2 are combined into a strong magnetic rough concentrate, and strong magnetic concentration is carried out with a magnetic field strength of 1.5T and a pulsating impulse of 150r / min to obtain iron lithium mica concentrate 1 and a concentrated middling ore; the concentrated middling ore is subjected to strong magnetic scavenging again with a magnetic field strength of 1.3T and a pulsating impulse of 100r / min to obtain a strong magnetic scavenging concentrate (returned to strong magnetic concentration) and a strong magnetic tailing 2.

[0205] The process flow of comparative example 9 is as follows Figure 3 The test results are shown in Table 3 and Table 4.

[0206] Comparative Example 10

[0207] This comparative example adopts the process of "pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal - flotation after desliming of lithophile mica". The process flow of pre-classification of raw ore - grinding - classification - gravity separation to recover tungsten and tin - weak magnetic impurity removal is the same as that of Example 2, except that the lithophile mica separation adopts a full flotation process (desliming). The weak magnetic tailings obtained after weak magnetic impurity removal are deslimed to obtain the deslimed weak magnetic tailings and mud concentrate, and then the deslimed weak magnetic tailings and mud concentrate are subjected to lithophile mica flotation.

[0208] The weak magnetic tailings desludging operation adopts the siphon method to desludging, with a sedimentation time of 3 minutes. Fine mud is extracted to obtain desludged weak magnetic tailings and mud concentrate.

[0209] 1) After desludging, the weak magnetic tailings are flotation-processed to recover ferrolithium mica, using a process of one coarse, two sweeps, and two refinements:

[0210] Primary roughing: add 150g / t of sodium hexametaphosphate to the deslimed weak magnetic tailings, stir for 2 minutes, add 1300g / t of LC-, stir for 3 minutes, and flotate for 3.5 minutes to obtain rough concentrate and roughing tailings;

[0211] Secondary scanning:

[0212] Scavenging 1: add LC-1200g / t to the roughing tailings, stir for 3 minutes, and flotate for 1.5 minutes to obtain scavenging 1 concentrate (return to roughing) and scavenging 1 tailings;

[0213] Scavenging 2: Add LC-1100g / t to the scavenging 1 tailings, stir for 3 minutes, and flotate for 1 minute to obtain scavenging 2 concentrate (return to scavenging 1 operation) and flotation tailings 1;

[0214] Second selection:

[0215] Concentration 1: The coarse concentrate is subjected to blank concentration and flotation for 3 minutes to obtain concentrate 1 and medium 1 (return to roughing);

[0216] Selection 2: The concentrate from Selection 1 is subjected to blank selection and flotation for 2 minutes to obtain iron lithium mica concentrate 1 and medium 2 (return to Selection 1 operation).

[0217] 2) Slime concentrate separation The reagent system and separation process for -0.038mm strong magnetic tailings separation in Example 2 were adopted to obtain iron lithium mica concentrate 2 and flotation tailings 2.

[0218] The process flow of Comparative Example 10 is as follows Figure 5 The test results are shown in Tables 3 and 4.

[0219] Comparative Example 11

[0220] The whole process process is basically the same as that of Example 2, except that the iron lithium mica collector adopts a combination of cationic collector A-2 and anionic collector B-3 (LC-1AB), and the collectors A-2 and B-3 are respectively prepared into a solution with a mass concentration of 5%, and then added to the slurry at the same time according to the mass percentage of 12%:88%.

[0221] The fine-grained iron lithium mica collector adopts a combination of cationic collector D-2 and anionic collector B-4 (LC-2DB). The collectors D-2 and B-4 are respectively prepared into a solution with a mass concentration of 5%, and then added to the slurry at the same time according to the mass percentage of 20%:80%.

[0222] The flotation process and flotation pulp conditions are basically the same as those in Example 2, but the flotation reagents are:

[0223] Strong magnetic concentrate flotation:

[0224] Roughing: LC-1AB 300g / t; Sweeping 1: LC-1AB 200g / t; Sweeping 2: LC-1AB 150g / t; Sweeping 3: LC-1AB 100g / t; other reagent systems remain unchanged.

[0225] -0.038mm strong magnetic tailings flotation:

[0226] Roughing: LC-2DB 800g / t; Sweeping 1: LC-2DB 300g / t; Sweeping 2: LC-2DB 200g / t; Sweeping 3: LC-2DB 150g / t; other reagent systems remain unchanged.

[0227] The process flow of comparative example 11 is as follows Figure 4 The test results are shown in Tables 3 and 4.

[0228] Comparative Example 12

[0229] The whole process process is basically the same as that of Example 2, except that the iron lithium mica collector adopts a combination of cationic collector A-2 and anionic collector C-3 (LC-1AC), and the collectors A-2 and C-3 are respectively prepared into a solution with a mass concentration of 5%, and then added to the slurry at the same time according to the mass percentage of 12%:88%.

[0230] The fine-grained lithium iron mica collector adopts a combination of cationic collector D-2 and anionic collector C-4 (LC-2DC). The collectors D-2 and C-4 are respectively prepared into a solution with a mass concentration of 5%, and then added to the slurry at the same time according to the mass percentage of 20%:80%.

[0231] The flotation process and flotation pulp conditions are basically the same as those in Example 2, but the flotation reagents are:

[0232] Strong magnetic concentrate flotation:

[0233] Roughing: LC-1AC 300g / t; Sweeping 1: LC-1AC 200g / t; Sweeping 2: LC-1AC 150g / t; Sweeping 3: LC-1AC 100g / t; other reagent systems remain unchanged.

[0234] -0.038mm strong magnetic tailings flotation:

[0235] Roughing: LC-2DC 800g / t; Scavenging 1: LC-2DC 300g / t; Scavenging 2: LC-2DC 200g / t; Scavenging 3: LC-2DC 150g / t; other reagent systems remain unchanged.

[0236] The process flow of comparative example 12 is referenced to Figure 4 The test results are shown in Tables 3 and 4.

[0237] Table 3 Test results of tungsten and tin separation in Example 2 and Comparative Examples 9 to 12 (%

[0238]

[0239] Table 4 Comparative test results of lithium separation schemes in Example 2 and Comparative Examples 9 to 12 / %

[0240]

[0241]

[0242] As shown in Table 3, Example 2 and Comparative Examples 9-12 all employed the "ore pre-classification - grinding - classification - tungsten-tin recovery by gravity separation - weak magnetic iron removal" process, resulting in a tungsten-tin concentrate with a WO3 grade of 17.41%, a Sn grade of 14.63%, a WO3 recovery rate of 69.64%, and a Sn recovery rate of 73.15%. The Li2O loss rate in the tungsten-tin concentrate and weak magnetic concentrate was 0.34%. The Li2O grade in the ferrolithium mica separation feed was 0.37%, and the Li2O recovery rate was 99.66%, achieving efficient recovery of low-grade tungsten-tin, while also minimizing lithium loss in the tungsten-tin recovery process.

[0243] It can be seen from Table 4 that (1) in Example 2, the "strong magnetic pre-enrichment-strong magnetic concentrate flotation-strong magnetic tailings flotation fine particles" process is adopted, and the Li2O grade in the iron lithium mica concentrate 1 is 2.17%, and the Li2O operation recovery rate is 82.81%. The Li2O grade in the iron lithium mica concentrate 2 is 1.51%, and the Li2O operation recovery rate is 7.14%. The Li2O grade in the combined iron lithium mica concentrate is 2.10%, the Li2O operation recovery rate is 89.95%, and the total Li2O recovery rate is 89.64%; (2) in Comparative Example 9, the "full process strong magnetic" process is adopted. Compared with the flotation operation, the strong magnetic operation has serious mechanical entrainment, which is not conducive to obtaining high-grade concentrate products. The Li2O grade in the obtained iron lithium mica concentrate 1 is 1.61%, and the Li2O operation recovery rate in the concentrate is 72.18%. Compared with the iron lithium mica concentrate 1 in Example 2, the Li2O grade is reduced by 0.56 percentage points, and the Li2O recovery rate is reduced by 10.63 percentage points. (3) In Comparative Example 10, the iron lithium mica is flotated after desliming. After the ore slime is removed in advance, the interference of the ore slime on the flotation of the iron lithium mica is reduced. The Li2O grade in the iron lithium mica concentrate 1 is 2.04%, but the Li2O loss rate in the mud concentrate is as high as 15.26%. The deslimed product in this comparative example is recovered by the fine particle enhanced flotation method of the present invention, and LC-2 is used as a collector. The Li2O grade in the iron lithium mica concentrate 2 is 1.94%, and the Li2O recovery rate is 8.59%. The Li2O grade in the combined iron lithium mica concentrate is 2.03%, and the Li2O recovery rate is still low, at 76.44%. (4) In Comparative Examples 11-12, when the magnetic concentrate and the magnetic tailings -0.038 mm were separately floated, two of the three components in LC-1, the cationic collector combination AB or AC, and the two components in LC-2, the cationic collector combination DB or DC, were used. The Li2O grade of the obtained iron lithium mica concentrate 1 was 1.34% or 1.52%, and the Li2O recovery rate was low, at 65.04% or 72.14%, respectively; the Li2O grade of the obtained iron lithium mica concentrate 2 was 0.52% or 0.63%, and the Li2O recovery rate was 2.21% or 3.61%, respectively.

[0244] In summary, regarding the comparison of the iron lithium mica separation process: ① Compared with the "full process magnetic separation" (Comparative Example 9) and the "desliming-flotation-desliming product reselection fine particles" (Comparative Example 10), the "strong magnetic-strong magnetic concentrate flotation-strong magnetic tailings flotation fine particles" process (Example 2) in the present invention is simple and easy to operate, the strong magnetic concentrate flotation is less disturbed by the ore slime, the reagent cost is low, and it is easier to obtain a lithium concentrate product with better indicators (the Li2O grade in the combined iron lithium mica concentrate is 2.10%, and the total Li2O recovery rate is 89.64%). At the same time, the enhanced recovery technology of fine-grained lithobite of the present invention was used to recover fine-grained lithobite from the desliming product in Comparative Example 10. The Li2O grade in the obtained lithobite concentrate 2 was 1.94%, and the Li2O operation recovery rate was 8.59%, indicating that the enhanced recovery effect of fine particles in the present invention is highly applicable and has a good recovery effect. Regarding the comparison of lithobite flotation collectors, compared with the two-component anion-cation combination in the LC series reagents, the strong magnetic concentrate and the strong magnetic tailings -0.038mm particle size of the present invention both adopt the anion-anion-cation three-component combination. The lithobite concentrate 1 has the highest Li2O grade of 2.17% and the highest Li2O operation recovery rate of 82.81%. The lithobite concentrate 2 also has the highest Li2O grade of 1.51% and the Li2O operation recovery rate of 7.14%. It also shows that the anion-anion-cationic collector combination in the present invention is not just a simple combination of different types of anion and cation collectors, but the three components of cationic collector A and anionic collector B / C or cationic collector D and anionic collector B / C produce a positive synergistic effect, thereby improving the flotation index of iron lepidolite.

[0245] By comparing the experimental results of Example 1, Example 2 and Comparative Examples 1 to 12, it can be seen that the method of the present invention has high separation efficiency, is less affected by ore mud, has low reagent cost, and the obtained iron lithium mica concentrate has a high Li2O grade and a high Li2O recovery rate. The product can be directly used as a raw material for lithium extraction. In addition, the separation operation does not require pre-desludging, and the entire separation process is simple and environmentally friendly. At the same time, the reagents and separation methods for enhanced flotation of fine-grained iron lithium mica proposed in the present invention are highly applicable and have good separation indicators. In summary, the present invention provides two economical, efficient, green and easy-to-implement iron lithium mica flotation collectors and an efficient separation method for the efficient separation and recovery of lithium ore.

Claims

1. A method for efficient and comprehensive recovery of low-grade lithium-tungsten-tin polymetallic ore, comprising the following steps: 1) Pre-classification of raw ore followed by grinding: The crushed raw ore is pre-classified using a sieve with a sieve aperture of 0.074 mm to obtain ore samples with a particle size of +0.074 mm and ore samples with a particle size of -0.074 mm. The +0.074 mm particle size sample is then wet-ball milled to obtain a ground slurry. The ground slurry and the -0.074 mm particle size sample are then combined as the selected raw ore slurry. 2) Wet classification: The raw ore slurry obtained in step 1) is wet classified to be divided into +0.074 mm particle size ore sample, -0.074+0.038 mm particle size ore sample and -0.038 mm particle size ore sample; 3) Recycling tungsten and tin by gravity separation: The three particle size ore samples obtained in step 2) are subjected to chute + shaking table gravity separation to obtain three particle size tungsten-tin concentrates, gravity separation ore, and gravity separation tailings respectively; the three particle size tungsten-tin concentrates are combined to obtain tungsten-tin concentrate; 4) Weak magnetic impurity removal: The gravity separation ore and gravity separation tailings of the three particle sizes obtained in step 3) are combined as the iron lithium mica separation feed, and weak magnetic separation and impurity removal are performed to obtain weak magnetic concentrate and weak magnetic tailings; 5) Strong magnetic separation of weak magnetic tailings: strong magnetic separation is performed on weak magnetic tailings to obtain strong magnetic concentrate and strong magnetic tailings; 6) Flotation of strong magnetic concentrate: Gangue inhibitor and lepidolite collector LC-1 were added to the strong magnetic concentrate to carry out lepidolite flotation to obtain lepidolite concentrate 1 and flotation tailings 1; 7) Wet classification of strong magnetic tailings: The strong magnetic tailings are wet classified into +0.038 mm particle size strong magnetic tailings and -0.038 mm particle size strong magnetic tailings; 8) Flotation of -0.038 mm particle size strong magnetic tailings: Add a regulator, an inhibitor, and a fine-grained lepidolite collector LC-2 to the -0.038 mm particle size strong magnetic tailings in step 7) to perform enhanced flotation of the fine-grained lepidolite to obtain lepidolite concentrate 2 and flotation tailings 2; in, The iron lithium mica collector LC-1 is based on the total mass of its active components, and its active components are composed of the following mass percentages: 5-20% of cationic collector A, 45-50% of anionic collector B, and the balance of anionic collector C; the cationic collector A is composed of dodecylamine and isopropyl alcohol in a mass ratio of (5-3):1; the anionic collector B is saponified oleic acid; the anionic collector C is composed of sodium dodecylsulfonate, C 12-14 The fatty alcohol polyoxyethylene ether is composed of a mass ratio of 1:(1-2); in the LC-1, the mass concentration of the active component is 5-10%; The fine-grained lithium iron mica collector LC-2 is based on the total mass of its active components, and its active components are composed of the following mass percentages: cationic collector D 10-35%, anionic collector B 10-50%, and anionic collector C 20-65%; the cationic collector D is composed of dodecylamine, isopropyl alcohol, kerosene, and carboxymethyl cellulose in a mass ratio of (11-9):(2-4):(2-4):1; the anionic collector B is saponified oleic acid; the anionic collector C is composed of sodium dodecylsulfonate, C 12-14 The fatty alcohol polyoxyethylene ether is composed of a mass ratio of 1:(1-2); in the LC-2, the mass concentration of the active component is 5-10%; In step 4), the weak magnetic separation and impurity removal adopts a primary roughing process with a magnetic field strength of 0.3-0.4 T; In step 5), the high-intensity magnetic separation adopts a primary roughing and secondary scavenging process, and the specific conditions include: the roughing magnetic field strength is 1.0-1.5 T, and the pulsating pulse frequency is 50-250 r / min; the magnetic field strength of the scavenging first is 1.0-2.0 T, and the pulsating pulse frequency is 0-150 r / min; the magnetic field strength of the scavenging second is 1.0-2.0 T, and the pulsating pulse frequency is 0-150 r / min; In step 6), the gangue inhibitor is a sodium hexametaphosphate solution with a mass concentration of 3-5%; the flotation process is one roughing process and two to four scavenging processes; and the stirring speed of the flotation machine during the flotation process is 1600-2000 r / min.

2. The method according to claim 1, characterized in that In the step 1), the +0.074 mm particle size ore sample is wet ball milled and combined with the -0.074 mm particle size ore sample, and the fineness of the combined ore is -0.074 mm, accounting for 40-65%.

3. The method according to claim 1, characterized in that In step 3), the tungsten-tin recovery by gravity separation adopts a combination of a spiral chute and a shaking table. The process is chute roughing - chute middling scavenging - chute concentrate roughing and shaking table cleaning; taking the +0.074mm particle size ore sample as an example, the specific process includes the following steps: ① Chute roughing: roughing of the +0.074 mm particle size ore sample to obtain chute fine 1, chute middle 1 and chute tail 1; ② Chute scavenging: Feed the chute middle 1 obtained in ① into the chute for scavenging to obtain chute fine 2, chute middle 2 and chute tail 2; ③ Shaking table roughing: The chute concentrate 1 obtained in ① and the chute concentrate 2 obtained in ② are combined and fed into the shaking table for fine selection to obtain shaking table concentrate 1, shaking table middle 1 and shaking table tail 1 respectively; ④ Shaker selection: Shaker concentrate 1 obtained in ③ is further subjected to shaker selection to obtain shaker concentrate 2, shaker middle 2 and shaker tail 2; The obtained chute tail 1, chute tail 2, shaking table tail 1, and shaking table tail 2 are combined into gravity separation tailings; the obtained chute middle 2, shaking table middle 1, and shaking table middle 2 are combined into gravity separation ore; the obtained shaking table concentrate 2 is +0.074 mm tungsten-tin concentrate; The process is adopted to re-select -0.074+0.038 mm particle size ore samples and -0.038 mm particle size ore samples, respectively, to obtain -0.074+0.038 mm re-selection ore, re-selection tailings and tungsten-tin concentrate, and -0.038 mm re-selection ore, re-selection tailings and tungsten-tin concentrate; The obtained +0.074 mm tungsten-tin concentrate, -0.074+0.038 mm tungsten-tin concentrate, and -0.038 mm tungsten-tin concentrate are combined to obtain tungsten-tin concentrate.

4. The method according to claim 1, wherein In step 6), the flotation process is one roughing and four scavenging, including the following steps: Primary roughing: add 100-500 g / t of sodium hexametaphosphate to the strong magnetic concentrate, stir for 2-3 minutes, add 200-500 g / t of LC-1, stir for 2-3 minutes, and flotate for 2-5 minutes to obtain roughing concentrate and roughing tailings; Four scans: Sweep 1: Add LC-1 100-300 g / t to the rougher tailings, stir for 2-3 minutes, and float for 1-5 minutes to obtain sweep concentrate 1 and sweep 1 tailings; Scavenging 2: Add LC-1 50~300 g / t to the scavenging 1 tailings, stir for 2~3 minutes, and float for 1~5 minutes to obtain scavenging concentrate 2 and scavenging 2 tailings; Scavenging and selection 3: add LC-1 25~300 g / t to the scavenging and selection 2 tailings, stir for 2~3 minutes, and float for 1~3 minutes to obtain scavenging concentrate 3 and scavenging and selection 3 tailings; Sweep 4: Add LC-1 25-150 g / t to the sweep 3 tailings, stir for 2-3 minutes, and float for 1-3 minutes to obtain sweep concentrate 4 and flotation tailings 1; The rougher concentrate, sweep concentrate 1, sweep concentrate 2, sweep concentrate 3 and sweep concentrate 4 are combined into iron lithium mica concentrate 1.

5. The method according to claim 1, wherein In step 8), the adjusting agent is a sodium carbonate solution with a mass concentration of 5-10%; the gangue inhibitor is a sodium hexametaphosphate solution with a mass concentration of 3-5%; The flotation process consists of one roughing, three scavenging and two cleaning steps, including the following steps: Primary roughing: first add 500-3000 g / t of sodium carbonate to the -0.038 mm particle size strong magnetic tailings, stir for 3-10 minutes, then add 200-2000 g / t of sodium hexametaphosphate, stir for 2-3 minutes, then add 500-4000 g / t of LC-2, stir for 5-10 minutes, and float for 2-6 minutes to obtain roughing concentrate and roughing tailings; Three scans: Sweep 1: first add 250-1500 g / t of sodium carbonate to the rougher tailings, stir for 3-10 minutes, then add 100-1000 g / t of sodium hexametaphosphate, stir for 2-3 minutes, then add 250-2000 g / t of LC-2, stir for 5-10 minutes, and float for 2-4 minutes to obtain sweep 1 and sweep 1 tailings; Scavenging 2: Add LC-2 100-500 g / t to the scavenging 1 tailings, stir for 3-5 minutes, and float for 1-5 minutes to obtain scavenging concentrate 2 and scavenging 2 tailings; Sweep 3: Add LC-2 (100-500 g / t) to the scavenger 2 tailings, stir for 3-5 minutes, and float for 1-5 minutes to obtain scavenger concentrate 3 and flotation tailings 2; scavenger concentrates 1, 2, and 3 are returned to the previous operation in sequence; Second selection: Concentration 1: Blank concentration is performed on the rougher concentrate, and flotation is performed for 1 to 3 minutes to obtain concentrate 1 and middling 1; Concentration 2: blank concentration is carried out on the concentrate of Concentration 1, and flotation is carried out for 1-3 minutes to obtain iron lithium mica concentrate 2 and middling 2; All the intermediate ore is returned to the previous level of operation in sequence; The stirring speed of the flotation machine is 2000~2300 r / min.

Images