Flotation process method for preventing excessive argillization of lepidolite

Abstract

The invention relates to a lepidolite excessive argillization prevention flotation process method which comprises the following steps: S1, crushed lepidolite raw ore is conveyed into a ball mill through a belt conveyor for ore grinding operation; s2, the ore grinding and discharging product obtained in the step S1 is fed into a hydrocyclone to be subjected to grading treatment, and an underflow product and an overflow product are obtained; s3, distributing an underflow product obtained in the step S2 to each five-lamination high-frequency vibrating screen for grading; s4, obtaining oversize products and undersize products by the five-laminated high-frequency vibrating screen in the step S3 through a grading process; s5, the oversize product obtained in the step S4 is fed into the ball mill in the step S1 to be subjected to ore grinding again, and an ore grinding classification closed circuit is formed; s6, undersize products obtained in the step S4 and overflow products obtained in the step S2 are collected and conveyed to flotation operation; and S7, flotation operation is conducted. The ore grinding grading system is optimized, and the lepidolite concentrate grade and the production benefit are improved.

Description

Technical Field

[0001] The invention relates to the technical field of ore dressing, in particular to a flotation process for preventing lepidolite from becoming overly muddy. Background Art

[0002] Lithium is an important material for the new energy vehicle industry. Lithium resources mainly come from salt lake lithium, spodumene ore, and lithium mica ore. In Yichun area, it is mainly lithium mica ore, with an average lithium grade of 0.5%. Due to the flaky nature of lithium mica, it is difficult to grind. If the particle size of lithium mica does not meet certain requirements, the lithium mica is not completely dissociated, which will lead to a decrease in the grade of the lithium mica concentrate. At the same time, feldspar products are prone to over-grinding and over-mudding. Over-mudding will lead to instability in the subsequent flotation process and affect the flotation product indicators. Therefore, it is necessary to separate the unqualified coarse particles in the primary grinding product, and try not to mix qualified fine particles.

[0003] In the prior art, the flotation process for lithium mica in the ore dressing plant usually adopts a single hydrocyclone classification, a single high-frequency vibrating screen classification, and a single spiral classifier classification. The single hydrocyclone classification process has the problem that the unqualified particle size materials returned to the ball mill for re-grinding are mixed with a lot of qualified particle size materials, and the qualified materials are easily over-sludged when re-grinded. The single high-frequency vibrating screen classification has the highest efficiency for particle size classification, but the limited processing capacity of a single unit greatly limits the production capacity. The single spiral classifier classification can guarantee the production processing capacity, but the classification efficiency of the equipment is low, the equipment is bulky, and the floor space is large. The above-mentioned single equipment classification processes have certain disadvantages and cannot meet the requirements of the production process to prevent over-sludge grinding and processing capacity. Summary of the invention

[0004] The invention aims to provide a reasonable and effective flotation process method for preventing over-slitting of lepidolite in view of the fact that conventional technologies used in lepidolite concentrators cannot solve the problem of over-slitting and the like. The invention realizes protective grinding and prevents over-slitting of ore through a combined grinding and grading method of a hydrocyclone and a five-layer high-frequency vibrating screen, thereby achieving efficient particle size grading of lepidolite grinding products and helping to improve the effect of the flotation process.

[0005] The technical solution adopted by the present invention is as follows: A flotation process for preventing lepidolite from becoming too muddy, the specific technical scheme comprises the following steps: Step S1, conveying the crushed lepidolite ore to a ball mill through a belt conveyor for grinding; Step S2, feeding the grinding discharge product obtained in step S1 into the hydrocyclone pump pool and adding water to obtain slurry, and conveying the slurry to the hydrocyclone through a slurry pump for classification treatment, and obtaining underflow product and overflow product after classification treatment in the hydrocyclone; Step S3, the underflow product obtained in step S2 enters the slurry distributor by gravity flow and is evenly distributed to each five-layer high-frequency vibrating screen for classification; Step S4, in step S3, the five-layer high-frequency screen vibrating screen obtains an oversize product and an undersize product through a grading process, wherein the undersize product is 0.25 mm or less and the oversize product is 0.25 mm or more; Step S5, feeding the oversize product obtained in step S4 into the ball mill in step S1 for re-grinding to form a grinding and grading closed circuit; Step S6, collecting the undersize product obtained in step S4 and the overflow product obtained in step S2 into the same pump pool, and transporting them to the flotation operation through a slurry pump; Step S7, flotation operation is performed on the ore pulp sent to the flotation equipment in step S6 by adding flotation collector and inhibitor.

[0006] As a further improvement of the above technical solution: The grinding operation of step S1 also includes: Step S1-1, the material after ball milling in step S1 enters a first-stage spiral classifier, the underflow sediment of the first-stage spiral classifier enters a first-stage rod mill, and then enters a second-stage spiral classifier, and the overflow product of the first-stage spiral classifier enters step S2 for operation; Step S1-2, the underflow sediment of the second-stage spiral classifier in step S1-1 passes through the second-stage rod mill and then enters the third-stage spiral classifier, and the overflow product of the second-stage spiral classifier enters step S2 for operation; Step S1-3, the underflow sediment of the three-stage spiral classifier in step S1-2 is returned to the first-stage rod mill in step S1-1 for regrinding, and the overflow product of the three-stage spiral classifier enters step S2 for operation.

[0007] In the grinding operation of step S1, the particle size of the lepidolite ore is less than or equal to 12 mm, the lithium content of the lepidolite ore is about 0.5%, and the ball mill is loaded with steel balls.

[0008] In step S2, the pressure of the hydrocyclone is controlled to be between 0.05 MPa and 0.10 MPa.

[0009] In step S2, the classified particle size below 0.2 mm is controlled as overflow product, and the particle size above 0.2 mm is underflow product. The overflow product is the qualified particle size required for the subsequent process.

[0010] Step S7, adding flotation collector and inhibitor into the flotation stirring barrel, so that the reagent and the slurry are fully and evenly mixed and enter the flotation roughing operation, the foam product is the lepidolite roughing concentrate product, and the other part is the roughing tailings product.

[0011] Step S8, feeding the roughing concentrate product in step S7 to the first selection process, the foam product is the first selection concentrate product, and the other part is the first selection intermediate product; Step S9, the concentrate product of step S8 is continuously fed to the second selection operation, the foam product is the lithium mica concentrate product, and the other part is the second selection medium ore product; Step S10, combining the second selected ore product in step S9 with the rougher selected concentrate product in step S7 to perform a first selected operation, forming a closed-loop operation; Step S11, the roughing tailings in step S7 are continuously fed into the scavenging operation 1, and the obtained foam product is the scavenging 1 intermediate product, and the other part is the scavenging 1 tailings product; Step S12, combining the scavenging-concentrate product obtained in step S11 and the beneficiated-medium ore product obtained in step S8 and returning them to the roughing operation to form a large flotation closed circuit; Step S13, the scavenging tailings product obtained in step S11 is further fed to the scavenging operation 2, and the obtained foam product is the scavenging 2 concentrate product, and the other part is the feldspar product.

[0012] In step S14, the scavenging second concentrate product obtained in step S13 and the scavenging first concentrate product obtained in step S11 are combined and returned to the roughing operation in step S7.

[0013] The beneficial effects of the present invention are as follows: The present invention adopts a combination of a hydrocyclone and a five-layer high-frequency vibrating screen. After the raw ore is ground in a ball mill, it is pumped to a hydrocyclone for preliminary classification to meet the processing capacity requirements and solve the problem of the spiral classifier occupying too much area. The bottom flow of the hydrocyclone is then classified by a five-layer high-frequency screen to ensure that the material returned to the ball mill is less entrained and prevent excessive mud from being ground. This process achieves the optimal state of the grinding and grading system through a combined grading process of a hydrocyclone and a five-layer high-frequency screen, thereby improving the grade of lithium mica concentrate and improving production efficiency.

[0014] The present invention uses a hydrocyclone and a five-layer high-frequency vibrating screen for grading to improve the process, which solves the limitation of using a spiral classifier with a large floor space under space-constrained conditions, greatly improves the space utilization rate of the production workshop, and uses the advantage of the high grading efficiency of the five-layer high-frequency vibrating screen to solve the serious problem of the bottom flow of the hydrocyclone grading, and prevents the grinding from being too muddy. The present invention uses a combined grading process flow of a hydrocyclone and a five-layer high-frequency vibrating screen, and the grinding -80 mesh particle size accounts for more than 85%, and the -400 mesh particle size accounts for less than 30%, ensuring that the particle size of the product entering the flotation operation meets the process requirements and the mud content is stable within the normal range. The particle size entering the flotation operation is not too muddy, which can realize the continuous and stable production of the flotation operation, and can effectively improve the recovery rate of lithium mica concentrate, so that the recovery rate reaches more than 78%, reduce the cost of production reagents, and increase the economic benefits of the enterprise.

[0015] The invention ensures the particle size of the grinding product through the technological innovation of the spiral classifier, the hydrocyclone and the five-layer high-frequency vibrating screen, provides good conditions for the flotation process of lithium mica, and greatly improves the product grade. The process improvement of the invention does not require major changes in the equipment, and can be used to transform the existing lithium mica beneficiation plant, which has wide applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The figure is a schematic flow chart of the flotation process of lepidolite to prevent mudification according to the present invention. DETAILED DESCRIPTION

[0017] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0018] Reference Figure 1 As shown, the present invention discloses a method for flotation of lithium mica to prevent mudification, and the specific technical scheme comprises the following steps: Step S1, the crushed lithium mica ore is conveyed to a ball mill through a belt conveyor for grinding, the particle size of the lithium mica ore is less than or equal to 12 mm, the lithium content of the lithium mica ore is about 0.5%, and the ball mill is loaded with steel balls. The grinding operation of step S1 also includes: Step S1-1, the material after ball milling in step S1 enters a first-stage spiral classifier, the underflow sediment of the first-stage spiral classifier enters a first-stage rod mill, and then enters a second-stage spiral classifier, and the overflow product of the first-stage spiral classifier enters step S2 for operation; Step S1-2, the underflow sediment of the second-stage spiral classifier in step S1-1 passes through the second-stage rod mill and then enters the third-stage spiral classifier, and the overflow product of the second-stage spiral classifier enters step S2 for operation; Step S1-3, the underflow sediment of the three-stage spiral classifier in step S1-2 is returned to the first-stage rod mill in step S1-1 for regrinding, and the overflow product of the three-stage spiral classifier enters step S2 for operation.

[0019] Step S2, feed the grinding discharge product obtained in step S1 into the hydrocyclone pump pool and add water to obtain slurry, and the slurry is transported to the hydrocyclone through a slurry pump for classification treatment, and the pressure of the hydrocyclone is controlled at 0.05MPa to 0.10MPa. After classification treatment, the hydrocyclone obtains underflow products and overflow products. The overflow products are controlled to have a classification particle size of less than 0.2mm, and the underflow products are controlled to have a particle size of more than 0.2mm. The overflow products are the qualified particle size required for the subsequent process.

[0020] Step S3, the underflow product obtained in step S2 enters the slurry distributor by gravity flow and is evenly distributed to each five-layer high-frequency vibrating screen for classification.

[0021] Step S4, in step S3, the five-layer high-frequency screen vibrating screen obtains the oversize product and the undersize product through the grading process, the undersize product is the particle size below 0.25mm, and the oversize product is the particle size above 0.25mm. The undersize product is the qualified particle size required for the subsequent process, and the oversize product is the unqualified particle size.

[0022] Step S5, feeding the oversize product obtained in step S4 into the ball mill in step S1 for re-grinding to form a grinding and grading closed circuit.

[0023] Step S6, collecting the undersize product obtained in step S4 and the overflow product obtained in step S2 into the same pump pool, and transporting them to the flotation operation through a slurry pump.

[0024] Step S7, flotation operation is performed by adding flotation collectors and inhibitors to the slurry transported to the flotation equipment in step S6. Specifically, flotation collectors and inhibitors are added to the flotation stirring barrel, and the reagents and slurry are fully and evenly mixed before entering the flotation roughing operation. The foam product is the lepidolite roughing concentrate product, and the other part is the roughing tailings product.

[0025] Step S8, feeding the roughing concentrate product in step S7 to the first selection operation, the foam product is the first selection concentrate product, and the other part is the first selection intermediate product.

[0026] Step S9, the concentrate product of step S8 is continuously fed into the second selection operation, the foam product is the lithium mica concentrate product, and the other part is the second selection medium ore product.

[0027] Step S10, combining the second selected ore product in step S9 with the roughing concentrate product in step S7 to perform a first selection operation, forming a closed-loop operation.

[0028] Step S11, the roughing tailings in step S7 are further fed into the scavenging operation, and the foam product obtained is the scavenging ore product of the scavenging ore, and the other part is the scavenging tailings product of the scavenging ore.

[0029] In step S12, the scavenging-concentrate product obtained in step S11 and the beneficiated-medium ore product obtained in step S8 are combined and returned to the roughing operation to form a large flotation closed circuit.

[0030] Step S13, the scavenging tailings product obtained in step S11 is further fed to the scavenging operation 2, and the obtained foam product is the scavenging 2 concentrate product, and the other part is the feldspar product.

[0031] In step S14, the scavenging second concentrate product obtained in step S13 and the scavenging first concentrate product obtained in step S11 are combined and returned to the roughing operation in step S7.

[0032] The invention ensures the particle size of the grinding product through the technological innovation of spiral classifier, hydrocyclone and high-frequency vibrating screen, provides good conditions for the flotation process of lithium mica, greatly improves the product grade, improves the subsequent lithium carbonate leaching rate, improves the recycling rate of lithium resources and greatly reduces the cost of mineral processing. With the increase of mining depth of lithium mines, the difficulty of grinding lithium ore has increased significantly. By changing the grinding medium, higher grinding efficiency can be achieved.

[0033] The present invention adopts a combined grading process of a hydrocyclone and a five-layer high-frequency vibrating screen, with the -80 mesh particle size accounting for more than 85% of the grinding, and the -400 mesh particle size accounting for less than 30%, ensuring that the particle size of the product entering the flotation operation meets the process requirements and the mud content is stable within the normal range. The final lithium mica concentrate obtained by the flotation process of the present invention has a lithium grade of more than 2.5%, a lithium recovery rate of more than 78%, and a whiteness of the feldspar product of more than 60.

[0034] The present invention adopts a combination of a hydrocyclone and a five-layer high-frequency vibrating screen. After the raw ore is ground in a ball mill, it is pumped to a hydrocyclone for preliminary classification to meet the processing capacity requirements and solve the problem of the spiral classifier occupying too much area. The bottom flow of the hydrocyclone is then classified by a five-layer high-frequency screen to ensure that the material returned to the ball mill is less entrained and prevent excessive mud from being ground. This process achieves the optimal state of the grinding and grading system through a combined grading process of a hydrocyclone and a five-layer high-frequency screen, thereby improving the grade of lithium mica concentrate and improving production efficiency.

[0035] In order to verify the effect of the present invention, comparative tests were carried out, and the comparative groups were set up as follows: Comparative Example 1 is a ball mill + hydrocyclone combination process used in the prior art, Comparative Example 2 is a ball mill + high-frequency vibrating screen combination process used in the prior art, and Comparative Example 3 is a ball mill + spiral classifier combination process used in the prior art. The test results of the comparative group and the embodiments of this patent are shown in Table 1 below.

[0036]

[0037] The ball mill feed particle sizes are selected into three groups, namely: the first group of particle sizes -5mm accounts for 63%, the second group of particle sizes -5mm accounts for 64%, and the third group of particle sizes -5mm accounts for 65%, which are respectively used in the scenarios of the embodiments of this patent, comparative example 1, comparative example 2 and comparative example 3.

[0038] Ball mill discharge column: It is a particle size composition of ore after being processed by ball mill. The proportion of -80 mesh in discharge is controlled to be greater than 30%, which is conducive to improving the efficiency of grading and screening. -400 mesh is controlled below 15% to prevent excessive mud in the back-end process.

[0039] The column of graded material discharge is the material index that enters the later process after the graded operation in the graded link. The -80 mesh of this material accounts for more than 85%, which ensures the complete dissociation of lepidolite. The -400 mesh is less than 30%, which prevents the feldspar product from being over-grinded and causing excessive mud.

[0040] The column of flotation mixing barrel is the material index entering the flotation operation. The -400 mesh of this material is controlled below 16%. This mud content (-400 mesh content) has little effect on the flotation operation, which can ensure the stability of the flotation operation and at the same time recover the fine lithium mica contained in the mud as much as possible.

[0041] It can be seen from the above experiments that the embodiment of the present invention can maintain certain superiority in graded discharge while making the proportion of materials entering the flotation operation with -400 mesh lower, better control over sliming, and better effects on lithium recovery rate and feldspar whiteness.

[0042] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A flotation process for preventing lepidolite from becoming too muddy, characterized in that: The following steps are involved: Step S1, conveying the crushed lepidolite ore into a ball mill through a belt conveyor for grinding; Step S2, feeding the grinding discharge product obtained in step S1 into a hydrocyclone pump pool and adding water to obtain slurry, and conveying the slurry to the hydrocyclone through a slurry pump for classification treatment, and obtaining underflow products and overflow products after classification treatment in the hydrocyclone; Step S3, the underflow product obtained in step S2 enters a slurry distributor through gravity flow and is evenly distributed to each five-layer high-frequency vibrating screen for classification; Step S4, the five-layer high-frequency screen in step S3 vibrates The sieve obtains an oversize product and an undersize product through a grading process, wherein the undersize product has a particle size of less than 0.25 mm, and the oversize product has a particle size of more than 0.25 mm; in step S5, the oversize product obtained in step S4 is fed into the ball mill of step S1 for re-grinding to form a grinding and grading closed circuit; in step S6, the undersize product obtained in step S4 and the overflow product obtained in step S2 are collected into the same pump pool and transported to the flotation operation through a slurry pump; in step S7, the slurry transported to the flotation equipment in step S6 is subjected to flotation operation by adding a flotation collector and an inhibitor.

2. The method for flotation of lepidolite to prevent overslime formation according to claim 1, wherein: The grinding operation of step S1 also includes: step S1-1, the material after being ground by the ball mill in step S1 enters a first-stage spiral classifier, the underflow sediment of the first-stage spiral classifier enters a first-stage rod mill, and then enters a second-stage spiral classifier, and the overflow product of the first-stage spiral classifier enters step S2 for operation; step S1-2, the underflow sediment of the second-stage spiral classifier in step S1-1 enters a third-stage spiral classifier after passing through the second-stage rod mill, and the overflow product of the second-stage spiral classifier enters step S2 for operation; step S1-3, the underflow sediment of the three-stage spiral classifier in step S1-2 returns to the first-stage rod mill of step S1-1 for re-grinding, and the overflow product of the three-stage spiral classifier enters step S2 for operation.

3. The flotation process for preventing lepidolite from being over-sludged according to claim 1, characterized in that: In the grinding operation of step S1, the particle size of the lepidolite ore is less than or equal to 12 mm, the lithium content of the lepidolite ore is about 0.5%, and the ball mill is loaded with steel balls.

4. The flotation process for preventing lepidolite from being over-sludged according to claim 1, characterized in that: In step S2, the pressure of the hydrocyclone is controlled to be between 0.05 MPa and 0.10 MPa.

5. The flotation process for preventing lepidolite from being over-sludged according to claim 1, characterized in that: In step S2, the classified particle size below 0.2 mm is controlled as overflow product, and the particle size above 0.2 mm is underflow product. The overflow product is the qualified particle size required for the subsequent process.

6. The method for flotation of lepidolite to prevent overslime formation according to claim 1, characterized in that: Step S7 further includes: adding flotation collectors and inhibitors into the flotation mixing barrel, so that the reagents and the slurry are fully and evenly mixed and enter the flotation roughing operation, the foam product is the lepidolite roughing concentrate product, and the other part is the roughing tailings product.

7. The flotation process for preventing lepidolite from becoming oversludged according to claim 6, characterized in that: The method further comprises the following steps: step S8, feeding the roughing concentrate product in step S7 to the first selection operation, wherein the foam product is the first selection concentrate product, and the other part is the first selection medium ore product; step S9, feeding the first selection concentrate product in step S8 to the second selection operation, wherein the foam product is the lepidolite concentrate product, and the other part is the second selection medium ore product; step S10, combining the second selection medium ore product in step S9 with the roughing concentrate product in step S7 to perform the first selection operation, forming a closed-loop operation; step S11, feeding the first selection concentrate product in step S8 to the second selection operation, wherein the foam product is the lepidolite concentrate product, and the other part is the second selection medium ore product; step S12, combining the second selection medium ore product in step S9 with the roughing concentrate product in step S7 to perform the first selection operation, forming a closed-loop operation; step S13, feeding the first selection concentrate product in step S8 to the second selection medium ore product, wherein the foam product is the first selection concentrate product, and the other part is the second selection medium ore product; step S14, combining the second selection medium ore product in step S9 with the roughing concentrate product in step S7 to perform the first selection operation, forming a closed-loop operation; step S15, feeding the first selection concentrate product in step S8 to the second selection medium ore product, wherein the foam product is the second selection medium ore product; Step S11, continue to feed the roughing tailings in step S7 to the scavenging operation 1, and the obtained foam product is the scavenging 1 intermediate ore product, and the other part is the scavenging 1 tailings product; Step S12, merge the scavenging 1 concentrate product obtained in step S11 and the concentrated 1 intermediate ore product obtained in step S8 and return them to the roughing operation to form a large flotation closed circuit; Step S13, continue to feed the scavenging 1 tailings product obtained in step S11 to the scavenging operation 2, and the obtained foam product is the scavenging 2 concentrate product, and the other part is the feldspar product.

8. The method for flotation of lepidolite to prevent overslime formation according to claim 7, characterized in that: The method further includes the following steps: Step S14, combining the scavenging second concentrate product obtained in Step S13 and the scavenging first concentrate product obtained in Step S11 and returning them to the roughing operation in Step S7.

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