Method for reducing lepidolite flotation froth and improving lepidolite recovery rate

Abstract

The invention relates to the field of ore flotation, and discloses a method for reducing lepidolite flotation froth and improving lepidolite recovery rate, which comprises the following steps: S1, ore grinding and grading: sequentially carrying out coarse crushing, intermediate crushing and fine crushing on spodumene and lepidolite complex disseminated mixed ore raw ore, grinding ore by adopting a ball mill, controlling the ore grinding concentration to be 70-80% and the ore grinding time to be 4-6 minutes, and carrying out ore grinding and grading; the ore grinding classification technology is optimized, the ore grinding classification technology is optimized, the proportion of-0.074 mm fraction in the ore grinding product reaches 65%-75%, the ore grinding product is classified through the hydrocyclone, coarse fraction returns to the ball mill to be ground again, and fine fraction enters the follow-up flotation operation, flotation froth is reduced, and by optimizing the ore grinding classification technology, the influence of fine particles generated by over-grinding on the froth stability is reduced; a special pretreatment regulator is added, so that the flotation activity of gangue minerals is inhibited, and unnecessary foam is reduced; and the formula and dosage of flotation reagents are adjusted, and foam increase caused by excessive reagents is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of ore flotation, and particularly to a method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite. Background Art

[0002] With the booming development of the new energy industry, lithium, as a key resource, has seen an explosive growth in demand. Lepidolite, as one of the important lithium ore resources, occupies an important position in the extraction of lithium. However, there are many problems in the flotation process of lepidolite.

[0003] On the one hand, lepidolite is intricately disseminated with minerals such as spodumene, the mineral composition is complex, the dissemination size is fine and uneven, and the physical and chemical properties between minerals are less different. This makes it difficult for traditional flotation processes to accurately separate, resulting in a low recovery rate of lepidolite. On the other hand, a large amount of flotation foam is generated during the flotation process. These foams not only increase the difficulty of subsequent treatment, extend the process flow, but also cause some lepidolite to be lost with the foam, further reducing the recovery rate of lepidolite, and at the same time increasing the production cost.

[0004] For example, when conventional flotation processes treat lepidolite ores, due to the similar floatability of lepidolite and associated minerals, a large amount of flotation reagents need to be added to enhance the separation effect. This not only causes waste of reagents, but also exacerbates the generation of flotation foam, making it difficult to improve the recovery efficiency of lepidolite. Therefore, it is urgent to develop a method that can effectively reduce the flotation foam of lepidolite and improve the recovery rate of lepidolite.

[0005] Therefore, it is necessary to provide a method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite to solve the above technical problems. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite to solve the existing problems in the above background art.

[0007] To achieve the above purpose, the present invention provides the following technical solutions:

[0008] A method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite, comprising the following steps:

[0009] S1. Grinding and classification: The raw ore of the mixed ore with intricate dissemination of spodumene and lepidolite is successively subjected to coarse crushing, medium crushing and fine crushing, and ball mill grinding is used. The grinding concentration is controlled at 70%-80%, the grinding time is 4-6 minutes, so that the proportion of the -0.074mm particle size grade in the grinding product reaches 65%-75%. The grinding product is classified by a hydrocyclone, the coarse particle grade is returned to the ball mill for re-grinding, and the fine particle grade enters the subsequent flotation operation;

[0010] S2. Add a pretreatment regulator: Before entering the spodumene flotation operation, add a pretreatment regulator, which is a mixture of sodium carbonate and water glass in a mass ratio of 3:2, to the fine-grained pulp after grinding and classification. The addition amount is 1000 - 1500 g / t, and stir the pulp for 90 - 120 minutes;

[0011] S3. Adjust the flotation reagent formula and dosage: Use a new collector composed of dodecylamine and sodium petroleum sulfonate in a mass ratio of 2:1 for spodumene flotation, and control the collector dosage at 700 - 900 g / t;

[0012] S4. Precisely control the flotation parameters: Control the spodumene flotation time to be 40 - 50 minutes, and the air inflow rate to be 0.3 - 0.5 m 3 / (m 2 ·min).

[0013] As a further solution of the present invention, in the grinding and classification step, the grinding concentration is preferably 76%, the grinding time is preferably 5 minutes, and the proportion of the -0.074 mm particle size in the grinding product preferably reaches 70%.

[0014] As a further solution of the present invention, in the step of adding the pretreatment regulator, the addition amount of the pretreatment regulator is preferably 1300 g / t, and the stirring time of the pulp is preferably 90 minutes.

[0015] As a further solution of the present invention, in the step of adjusting the flotation reagent formula and dosage, the dosage of the new collector is preferably 800 g / t.

[0016] As a further solution of the present invention, in the step of precisely controlling the flotation parameters, the flotation time is preferably 45 minutes, and the air inflow rate is preferably 0.4 m 3 / (m 2 ·min).

[0017] The present invention reduces flotation foam: By optimizing the grinding and classification process, the influence of fine particles generated by over-grinding on foam stability is reduced; adding a special pretreatment regulator inhibits the flotation activity of gangue minerals and reduces unnecessary foam generation; adjusting the flotation reagent formula and dosage reduces the increase in foam caused by excessive reagents. Combining these measures effectively reduces the foam amount in the spodumene flotation process, reduces the subsequent treatment difficulty, and shortens the process flow.

[0018] Improve the recovery rate: Precise control of the grinding and classification process ensures the monomer dissociation degree of lepidolite; Special pretreatment modifiers enhance the flotability difference between lepidolite and other minerals; The new collector has stronger selectivity and collecting ability; Precise control of flotation parameters creates the best conditions for lepidolite flotation. These measures work together to significantly improve the recovery rate of lepidolite. Compared with the traditional process, the recovery rate of lepidolite can be increased to more than [X]% (such as from a lower recovery rate to a higher level in the examples), realizing the efficient recovery and utilization of lepidolite resources.

[0019] Reduce costs: Reduce the dosage of flotation reagents, reducing production costs; At the same time, reduce the amount of flotation foam, shorten the process flow, reduce equipment energy consumption and labor costs, and improve production efficiency.

[0020] Environmental protection advantages: Reduce the usage amount of flotation reagents, reduce environmental pollution, and conform to the development concept of green environmental protection. Description of the Drawings

[0021] The present invention will be further described below in conjunction with the drawings and examples.

[0022] Figure 1 It is a broken line graph of the spodumene recovery rate of each embodiment of the present invention; Detailed Embodiments

[0023] Example 1

[0024] Raw material selection: Select the spodumene and lepidolite complex disseminated mixed ore raw ore from a certain mine in Jiangxi. The ore of this mine has typical complex dissemination characteristics. Spodumene and lepidolite are intertwined, and there are also various gangue minerals associated. After analysis by professional detection equipment, the spodumene grade is 0.8%, and the lepidolite grade is 0.55%.

[0025] Crushing and grinding: The raw ore is first coarsely crushed by a jaw crusher to break the larger ore blocks into a particle size range initially suitable for subsequent processing. Then, a cone crusher is used for medium crushing to further reduce the ore particle size. Finally, a pair-roll crusher is used for fine crushing. The finely crushed ore is fed into a ball mill, and the grinding concentration is set at 76%. The reason for choosing this concentration is that at this concentration, the collision efficiency between the grinding medium and the ore is higher, which can effectively improve the grinding effect and avoid over-grinding or insufficient grinding problems caused by too high or too low concentration. The grinding time is set at 5 minutes. After multiple tests and verifications, this time can not only ensure the monomer dissociation degree of spodumene and lepidolite, but also reduce the over-grinding phenomenon. After grinding, the proportion of the -0.074mm particle size fraction in the product reaches 70%, and this particle size distribution is beneficial to the subsequent flotation operation, enabling the minerals to better contact with the flotation reagents.

[0026] Classification operation: The ground ore product is classified by a hydrocyclone. The hydrocyclone utilizes the principle of centrifugal force to separate the ground ore products according to particle size. The coarse fraction, due to its larger particle size and not meeting the requirements of flotation, is returned to the ball mill for regrinding to further improve its monomer dissociation degree. The fine fraction enters the subsequent process for flotation preparation.

[0027] Flotation of lepidolite: 800 g / t of collector is added to the fine - sized pulp. This collector is specially selected according to the surface properties and floatability characteristics of lepidolite, and has good selectivity and collecting ability. The flotation time is set at 45 minutes, which is the optimal flotation time determined through a large number of previous experiments. Within this time, the collector can fully combine with lepidolite particles, causing them to float and form a foam layer. After obtaining the rough concentrate of lepidolite, one - stage cleaning is carried out. During the cleaning process, by adjusting the flotation conditions, impurities are further removed to improve the grade of the lepidolite concentrate. Finally, the grade of the lepidolite concentrate reaches 3.2% and the recovery rate is 32%.

[0028] Flotation of spodumene: The tailings from lepidolite flotation are first scavenged to recover the residual lepidolite in the tailings. 1300 g / t of sodium carbonate is added to the scavenged tailings to adjust the pH to 9. The role of sodium carbonate is to adjust the acidity and alkalinity of the pulp, change the charge properties of the mineral surface, and enhance the effect of spodumene and the collector. Stir for 90 minutes to ensure that sodium carbonate is fully mixed with the pulp. Then 1200 g / t of collector is added, and the reaction lasts for 126 minutes for spodumene flotation. The rough concentrate of spodumene is subjected to two - stage cleaning. Through multiple cleaning operations, the grade of the spodumene concentrate is gradually improved. Finally, the grade of the spodumene concentrate reaches 4.2% and the recovery rate is 47%.

[0029] Beneficial effects: In this embodiment, by precisely controlling the grinding and classification process, the over - grinding phenomenon is reduced, and the monomer dissociation degree of minerals is improved, providing good conditions for subsequent flotation. The special reagent formula and dosage enhance the selectivity of spodumene and lepidolite flotation, reduce the reagent consumption, and lower the production cost. At the same time, by precisely controlling the flotation parameters, the separation effect of spodumene and lepidolite is significantly improved. Compared with the traditional process, the grade of the lepidolite concentrate is increased, the recovery rate is also increased, and the spodumene concentrate also achieves good indicators, effectively improving the resource utilization rate and reducing environmental pollution.

[0030] Example 2

[0031] Raw material selection: The mixed ore raw ore from a certain mining area in Hunan is collected. The ore in this mining area is different from that in Jiangxi mines in terms of mineral composition and dissemination characteristics. The symbiotic relationship between spodumene and lepidolite is more complex, and the types and contents of gangue minerals also vary. After detection, the grade of spodumene is 0.75% and the grade of lepidolite is 0.5%.

[0032] Crushing and grinding: The same crusher combination as in Example 1 was used for crushing, i.e., jaw crusher for coarse crushing, cone crusher for medium crushing, and roll crusher for fine crushing. The crushed ore entered the ball mill, and the grinding concentration was controlled at 74%. This concentration was determined through experiments based on the characteristics of the ore in this mining area. At this concentration, the energy transfer during the grinding process is more efficient, enabling the ore to be fully ground. The grinding time was set at 5.5 minutes. Through comparative experiments with different grinding times, it was found that this time could achieve a good monomer dissociation state for spodumene and lepidolite, while not over-grinding other minerals. The proportion of the grinding product with a particle size of -0.074mm was 68%. Although this particle size proportion was slightly lower than that in Example 1, it could still meet the basic requirements for subsequent flotation.

[0033] Classification operation: The hydraulic cyclone was also used for classification. The coarse particle size fraction was returned to the ball mill for re-grinding, and the fine particle size fraction entered the flotation process. The classification process can effectively separate the coarse particles that do not meet the flotation particle size requirements, ensuring that the particle size of the minerals entering the flotation is uniform and improving the flotation efficiency.

[0034] Lepidolite flotation: 750 g / t of collector was added. Due to the nature characteristics of the ore in this mining area, the dosage of the collector was appropriately reduced. The flotation time was 42 minutes. This flotation time was determined by comprehensively considering the collector dosage and ore properties, which could ensure the full floating of lepidolite. The rough concentrate of lepidolite was subjected to 1 stage of cleaning. Through the cleaning operation, part of the impurities were removed, and the purity of the lepidolite concentrate was improved. Finally, the grade of the lepidolite concentrate was 3.0% and the recovery rate was 30%.

[0035] Spodumene flotation: The tailing treatment process of the lepidolite flotation was basically the same as that in Example 1. First, scavenging was carried out, then sodium carbonate was added to adjust the pH, and then the collector was added for flotation. Finally, the grade of the spodumene concentrate was 4.1% and the recovery rate was 46%.

[0036] Beneficial effects: Aiming at the characteristics of the ore in a certain mining area in Hunan, this example made targeted adjustments to parameters such as the grinding concentration and the dosage of flotation reagents. This flexible process adjustment method reflects the adaptability of this technology to different ore properties. By optimizing the process parameters, on the premise of ensuring the grades of spodumene and lepidolite concentrates, the recovery rate was increased, the waste of reagents was reduced, the production cost was lowered, and at the same time, the environmental pollution was reduced, realizing the efficient recovery and utilization of resources.

[0037] Example 3

[0038] Raw material selection: The mixed ore raw ore from a certain mine in Sichuan has unique mineral characteristics. The disseminated particle sizes of spodumene and lepidolite are relatively coarse, but the symbiotic relationship between the minerals is complex. After detection, the grade of spodumene is 0.85% and the grade of lepidolite is 0.6%.

[0039] Crushing and grinding: Conventional crushers are used in the crushing process to reduce the ore particle size to a suitable range. When grinding in a ball mill, the concentration is set to 78%. A higher grinding concentration is suitable for the relatively coarse particle size of the ore, which can improve grinding efficiency and reduce grinding time and energy consumption. The grinding time is 4.5 minutes. The shorter grinding time is because the ore particle size is coarse and does not require too long grinding. The grinding product -0.074mm accounts for 72%, and this particle size distribution provides a good foundation for subsequent flotation.

[0040] Classification: Hydrocyclones are used for classification, with the coarse particles returned for regrinding and the fine particles entering flotation. The classification process effectively controls the particle size of the minerals entering the flotation operation and improves the accuracy and efficiency of flotation.

[0041] Lepidolite flotation: 850g / t collector was added, and the amount of collector was appropriately increased according to the content and floatability of lepidolite in the ore. The flotation lasted for 48 minutes. The longer flotation time was helpful to fully recover the lepidolite. After the lepidolite rough concentrate was cleaned once, the final lepidolite concentrate grade was 3.5% and the recovery rate was 35%.

[0042] Spodumene flotation: After the lithium mica flotation tailings are treated, the spodumene concentrate grade is 4.3% and the recovery rate is 48%.

[0043] Beneficial effects: According to the characteristics of ore from a mine in Sichuan, the grinding concentration and time were adjusted to improve grinding efficiency and reduce energy consumption. At the same time, the flotation agent dosage and flotation time were reasonably adjusted to improve the concentrate grade and recovery rate of spodumene and lepidolite. This shows that this technology can be flexibly optimized according to the physical and chemical properties and embedding characteristics of different ores, has a wide range of applicability, effectively improves resource recovery efficiency, and reduces resource waste.

[0044] Example 4

[0045] Raw material selection: Mixed ore was obtained from a mine in Xinjiang. The spodumene and lepidolite content of the ore was relatively low, and the ore contained more clay gangue minerals, which brought certain difficulties to the sorting. After testing, the spodumene grade was 0.7% and the lepidolite grade was 0.45%.

[0046] Crushing and grinding: After crushing, the ball mill grinding concentration is 75%. This concentration is the result of proper adjustment considering the influence of clay gangue minerals in the ore, which can not only ensure the grinding effect, but also reduce the adverse effects of clay minerals on subsequent flotation. The grinding time is 5 minutes, ensuring that spodumene and lepidolite reach a certain degree of monomer dissociation. The grinding product -0.074mm accounts for 70%, which meets the particle size distribution requirements of flotation.

[0047] Classification operation: Hydrocyclone classification is adopted. The coarse particle size fraction is returned to the ball mill for regrinding, and the fine particle size fraction enters the flotation process. The classification operation effectively removes coarse particles and some clay minerals, improving the selectivity of flotation.

[0048] Lepidolite flotation: 800 g / t of collector is added and flotation is carried out for 45 minutes. After 1 time of cleaning of the coarse lepidolite concentrate, the final grade of the lepidolite concentrate is 2.8% and the recovery rate is 28%.

[0049] Spodumene flotation: After the tailings of lepidolite flotation are treated, the grade of the spodumene concentrate is 3.8% and the recovery rate is 42%.

[0050] Beneficial effects: Aiming at the characteristics that the ore in a certain mine in Xinjiang contains more clay gangue minerals, corresponding measures are taken in the grinding and flotation processes in this embodiment. By optimizing the grinding concentration, the interference of clay minerals on flotation is reduced; the dosage and time of flotation reagents are accurately controlled. Even when the contents of spodumene and lepidolite are relatively low, relatively good concentrate grades and recovery rates are still obtained, improving the resource utilization rate of low-grade ores and providing a feasible method for the separation of similar low-grade complex ores.

[0051] Example 5

[0052] Raw material selection: The mixed ore raw ore from a certain mine in Yunnan has relatively special dissemination characteristics of spodumene and lepidolite. Some lepidolite exists in the form of fine-grained inclusions in other minerals. After detection, the grade of spodumene is 0.9% and the grade of lepidolite is 0.65%.

[0053] Crushing and grinding: After crushing, ball mill grinding is carried out with a concentration of 77%. This concentration is to adapt to the special dissemination form of lepidolite in the ore and ensure that the lepidolite in the inclusions can be fully dissociated during the grinding process. The grinding time is 4.8 minutes. Through experiments, it is determined that this time can minimize over-grinding while dissociating as much lepidolite as possible. The proportion of the grinding product with a particle size of -0.074 mm is 71%, meeting the particle size requirements for flotation.

[0054] Classification operation: Hydrocyclone classification is carried out. The coarse particle size fraction is reground and the fine particle size fraction enters the flotation process. The classification process further optimizes the mineral particle size, creating good conditions for flotation.

[0055] Lepidolite flotation: 900 g / t of collector is added. Considering the content and special dissemination form of lepidolite, the dosage of the collector is appropriately increased. Flotation is carried out for 50 minutes. The longer flotation time helps to recover those lepidolite with greater dissociation difficulty. The coarse lepidolite concentrate is cleaned once, and the final grade of the lepidolite concentrate is 3.8% and the recovery rate is 38%.

[0056] Spodumene flotation: After the tailings of lepidolite flotation are treated, the grade of the spodumene concentrate is 4.5% and the recovery rate is 50%.

[0057] Beneficial effects: For the special dissemination form of lepidolite in the ore of a certain mine in Yunnan, the grinding and flotation process parameters are optimized in this embodiment. By adjusting the grinding concentration and time, the dissociation degree of lepidolite is improved; reasonably increasing the dosage of collector and flotation time effectively recover lepidolite and spodumene, and improve the concentrate grade and recovery rate. This reflects the adaptability of this technology to ores with special dissemination, provides an effective technical means for treating similar complex ores, and further expands the application scope of this technology.

Claims

1. A method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite, characterized in that, It includes the following steps: S1. Grinding and classification: The raw ore of the complex intergrown mixture of spodumene and lepidolite is successively subjected to coarse crushing, medium crushing and fine crushing, and then ground by a ball mill. The grinding concentration is controlled at 70%-80%, and the grinding time is 4-6 minutes, so that the proportion of the -0.074mm particle size fraction in the grinding product reaches 65%-75%. The grinding product is classified by a hydrocyclone. The coarse particle fraction is returned to the ball mill for re-grinding, and the fine particle fraction enters the subsequent flotation operation; S2. Adding a pretreatment regulator: Before entering the lepidolite flotation operation, a pretreatment regulator composed of sodium carbonate and water glass mixed in a mass ratio of 3:2 is added to the fine particle fraction pulp after grinding and classification. The addition amount is 1000-1500 g / t, and the pulp is stirred for 90-120 minutes; S3. Adjusting the flotation reagent formula and dosage: A new collector composed of dodecylamine and sodium petroleum sulfonate compounded in a mass ratio of 2:1 is used for lepidolite flotation, and the collector dosage is controlled at 700-900 g / t; S4. Precisely control the flotation parameters: control the flotation time of lepidolite to be 40 - 50 minutes, and the air inflow rate to be 0.3 - 0.5 m 3 / (m 2 ·min).

2. The method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite according to claim 1, wherein: In the grinding and classification step, the grinding concentration is preferably 76%, the grinding time is preferably 5 minutes, and the proportion of the -0.074mm particle size fraction in the grinding product preferably reaches 70%.

3. The method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite according to claim 2, wherein: In the step of adding the pretreatment regulator, the addition amount of the pretreatment regulator is preferably 1300 g / t, and the stirring time of the pulp is preferably 90 minutes.

4. The method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite according to claim 3, characterized in that: In the step of adjusting the flotation reagent formula and dosage, the dosage of the new collector is preferably 800 g / t.

5. The method for reducing the flotation foam of lepidolite and improving the recovery rate of lepidolite according to claim 4, wherein: In the step of precisely controlling the flotation parameters, the flotation time is preferably 45 minutes, and the aeration rate is preferably 0.4 m 3 / (m 2 ·min).

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