Method for extracting lithium from low-grade lepidolite and device thereof

Abstract

The application provides a low-grade lepidomelcite lithium extraction method and device. The low-grade lepidomelcite lithium extraction method comprises the following steps: S1, mechanical activation pretreatment: after crushing the raw ore, the planetary ball mill is used for treatment for 2h, the sodium polyacrylate dispersant is added, and ultrasonic treatment is performed. The low-grade lepidomelcite lithium extraction method and device provided by the application can increase the specific surface area of the treated mica by 3-5 times, greatly increase the contact area with the subsequent additives and leaching liquid, improve the subsequent roasting reaction rate and lithium leaching efficiency, reduce the waste of raw materials, adopt double additive cooperation and segmented roasting, greatly reduce the roasting temperature compared with the traditional process, greatly reduce the energy consumption, reduce the production energy consumption cost, the calcium fluoride reacts with the generated substances in the reaction process (calcium sulfate is generated), the fluorine element is in-situ fixed, the fluoride is avoided to escape, the industry environmental protection problem of fluorine pollution in the traditional process is solved, and the environmental protection emission requirement is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of metal recycling, in particular to a low-grade lepidolite lithium extraction method and device. BACKGROUND

[0002] With the rapid development of new energy industry, the demand for lithium is increasing. As one of the important sources of lithium resources, the research and development of lepidolite lithium extraction process is of great significance.

[0003] Lepidolite is one of the sources of lithium, and there are many methods for extracting lithium, mainly including acid method, alkali method, salt method, and pressure cooking method. Among them, the salt method is the most widely used, which is to roast salt and lepidolite at high temperature. The salt mainly includes sulfate, chloride, carbonate or mixture. Under high temperature roasting, the crystal structure of lepidolite is changed or destroyed, and becomes more loose. The lithium ions in lepidolite concentrate and the alkali metal ions in salt undergo ion exchange reaction, and the lithium ions are separated from the insoluble aluminosilicate to form soluble lithium salt. Then, through the leaching step, lithium can be extracted into the solution.

[0004] However, the traditional lepidolite lithium extraction process has the following technical bottlenecks: multiple roasting is required for low-grade ore, energy consumption is high, fluorine escapes causing environmental pollution, and impurity metals such as aluminum and iron are leached synchronously, resulting in low lithium comprehensive recovery rate.

[0005] Therefore, it is necessary to provide a low-grade lepidolite lithium extraction method and device to solve the above technical problems. SUMMARY

[0006] The present application provides a low-grade lepidolite lithium extraction method and device, which solves the problems of traditional process, such as multiple roasting for low-grade ore, high energy consumption, fluorine escaping causing environmental pollution, and synchronous leaching of impurity metals such as aluminum and iron, resulting in low lithium comprehensive recovery rate.

[0007] To solve the above technical problems, the low-grade lepidolite lithium extraction method provided by the present application includes the following steps:

[0008] S1, mechanical activation pretreatment: after crushing the raw ore, the planetary ball mill is used for treatment for 2h, and polyacrylic acid sodium dispersant is added for ultrasonic treatment;

[0009] S2, composite additive roasting: the ore powder, sodium sulfate and calcium fluoride are mixed and then subjected to staged roasting;

[0010] S3, selective leaching: sodium carbonate solution is added according to the liquid-solid ratio of 4:1, stirring for 2h, and adjusting the pH;

[0011] S4, deep purification: first removing Al(OH)3 through 5um filter membrane, then adsorbing residual metal ions through chelating resin, and finally evaporating and concentrating to Li +Concentration > 20g / L, cooling crystallization of battery-grade lithium carbonate.

[0012] Preferably, the S1 is broken to D50=10-50μm, the planetary ball mill is rotated at 300rpm, and the ball-to-material ratio is 5:1.

[0013] Preferably, the mass ratio of the S2, sodium sulfate, and calcium fluoride is 100:25:8.

[0014] Preferably, the low-grade lepidolite lithium extraction device comprises a box body and a reaction kettle, two support assemblies are installed on the top of the box body, the reaction kettle is installed between the two support assemblies, a feeding chute is installed on the top of the reaction kettle, a steam discharge pipe is installed on the top of the reaction kettle, a discharge chute is installed at the bottom of the reaction kettle, a rotating assembly is installed in the reaction kettle, a sliding rod is slidably connected inside the rotating assembly, a blocking assembly is installed at the bottom of the sliding rod, the blocking assembly is used to block the discharge chute, a first driving assembly is installed on the top of the reaction kettle, the first driving assembly is used to drive the rotating assembly to rotate, a second driving assembly is installed on the top of the reaction kettle, the second driving assembly is used to drive the sliding rod to move vertically, a feeding port is formed on the top of the box body, a circular ring is installed on the top of the box body, two rotating shafts are rotatably connected inside the box body, a filter membrane and a filter plate are respectively installed on the outer surfaces of the two rotating shafts, a layer of chelating resin is covered on the top of the filter plate, one end of each of the two rotating shafts penetrates through the box body and extends to the outside of the box body, a rotating gear is fixedly connected to one end of each of the two rotating shafts, a transmission assembly is installed on one of the support assemblies, the transmission assembly is used to drive the two rotating gears to rotate, a chelating resin loading box is installed on the right side of the box body, and a discharge port is formed on the bottom of the box body.

[0015] Preferably, the support assembly comprises a support rod, a support block, a sleeve rod, a connecting block, a limiting block, and a first elastic member, the support rod is fixed to the top of the box body, the support block is fixed to the outer surface of the support rod, the sleeve rod is sleeved on the outer surface of the support rod, the connecting block is fixed to the outer surface of the sleeve rod and is fixed to the reaction kettle, the limiting block is fixed to the top end of the support rod, and the first elastic member is arranged between the limiting block and the connecting block.

[0016] Preferably, the rotating assembly comprises a rotating rod, stirring blades, a cavity, a circular table, a fixing rod, a groove, a sliding block, a moving rod, a second elastic member and a scraper, the rotating rod is rotationally connected to the reaction kettle, the stirring blades are installed on the rotating rod, the cavity is arranged on the rotating rod, the circular table is installed on the outer surface of the sliding rod, the fixing rod is installed on the rotating rod, the groove is arranged on the fixing rod, the sliding block is slidingly connected in the groove, the moving rod is installed on the sliding block, the second elastic member is sleeved on the moving rod, and the scraper is fixed to one end of the moving rod.

[0017] Preferably, the blocking assembly comprises a blocking plate, a connecting rod and a roller, the blocking plate is fixed to the bottom end of the sliding rod, the connecting rod is fixed to one side of the blocking plate, and the roller is rotationally connected to the connecting rod.

[0018] Preferably, the first driving assembly comprises a driving member, a worm and a worm wheel, the driving member is fixed to the top of the reaction kettle, the worm is fixed to the output shaft of the driving member, and the worm wheel is installed on the rotating rod.

[0019] Preferably, the second driving assembly comprises a mounting plate, a pushing member and a moving plate, the mounting plate is fixed to the top of the reaction kettle, the pushing member is fixed to the mounting plate, the moving plate is slidingly connected to the mounting plate, the output end of the pushing member is fixedly connected with the moving plate, and the moving plate is rotationally connected with the sliding rod.

[0020] Preferably, the transmission assembly comprises an auxiliary block, a straight-toothed plate, a fixing rod and a fixing plate, the auxiliary block is slidingly connected to one side of the box body, the straight-toothed plate is fixed to the bottom of the auxiliary block, the fixing rod is fixed to the top of the auxiliary block, the fixing plate is fixed to the top of the fixing rod, and the fixing plate is fixed to the sleeve rod.

[0021] Compared with the related art, the low-grade lepidolite lithium extraction method and device have the following beneficial effects:

[0022] This invention provides a method and apparatus for lithium extraction from low-grade lepidolite. After treatment, the specific surface area of ​​the mica increases by 3-5 times, significantly increasing the contact area with subsequent additives and leachate. This improves the subsequent roasting reaction rate and lithium leaching efficiency, reduces raw material waste, and increases lithium recovery rate. The method employs a dual-agent, staged roasting process, which significantly lowers the roasting temperature compared to traditional processes, greatly reducing energy consumption and production costs. Calcium fluoride reacts with substances generated during the reaction (forming calcium sulfate), achieving in-situ fixation of fluorine and preventing fluoride escape. This solves the industry-wide environmental problem of fluorine pollution in traditional processes and meets environmental protection standards. To meet emission requirements, sodium sulfate can undergo a displacement reaction with Li in mica, converting lithium into a form that is easily leached later, laying the foundation for a high lithium leaching rate and facilitating lithium recovery. This also prevents excessive activation of impurities such as aluminum and iron during the roasting stage. Selective leaching removes most impurities in advance, reducing the processing load of subsequent deep purification processes, lowering purification costs and operational complexity. It also avoids the impact of impurities on the purity of lithium products. Furthermore, two-stage filtration and resin adsorption reduce lithium loss during purification. Combined with the preceding processes, the overall lithium recovery rate is significantly improved, preventing lithium resource waste and increasing raw material utilization and economic benefits. Attached Figure Description

[0023] Figure 1 This is a schematic flowchart of the lithium extraction method from low-grade lithium mica provided by the present invention.

[0024] Figure 2 A schematic diagram of the low-grade lithium mica lithium extraction device provided by the present invention;

[0025] Figure 3 for Figure 2 The diagram shows the structure of the transmission assembly.

[0026] Figure 4 for Figure 2 A schematic cross-sectional view of the reactor shown;

[0027] Figure 5 for Figure 4 The enlarged schematic diagram of part A shown below;

[0028] Figure 6 for Figure 4 The diagram shows the structure of the conversion component.

[0029] Figure 7 for Figure 6 The enlarged schematic diagram of section B is shown below;

[0030] Figure 8 An initial state diagram of the low-grade lithium mica lithium extraction device provided by the present invention;

[0031] Figure 9The motion state diagram of the low-grade lepidolite lithium extraction device provided by the application, wherein, Figure 9 (a) is the state diagram after the first extension of the pusher, Figure 9 (b) is the state diagram after the second extension of the pusher, Figure 9 (c) is the state diagram after the second extension of the pusher and the rotation of the driving part;

[0032] Figure 10 The motion state diagram of the filter membrane and the filter plate, wherein, Figure 10 (a) is the initial state diagram of the filter membrane and the filter plate, Figure 10 (b) is the schematic diagram of the rotation of the filter membrane and the filter plate to the vertical state, Figure 10 (c) is the state schematic diagram of the rotation of the filter membrane and the filter plate by half a circle.

[0033] Reference numerals in the drawings:

[0034] 1, box body, 2, reaction kettle;

[0035] 3, support assembly, 31, support rod, 32, support block, 33, sleeve rod, 34, connecting block, 35, limiting block, 36, first elastic member;

[0036] 4, feeding groove, 5, steam discharge pipe, 6, discharge groove;

[0037] 7, rotating assembly, 71, rotating rod, 72, stirring blade, 73, cavity, 74, circular table, 75, fixed rod, 76, groove, 77, sliding block, 78, moving rod, 79, second elastic member, 710, scraper;

[0038] 8, sliding rod;

[0039] 9, plugging assembly, 91, plugging plate, 92, connecting rod, 93, roller;

[0040] 10, first driving assembly, 101, driving part, 102, worm, 103, worm gear;

[0041] 11, second driving assembly, 111, mounting plate, 112, pusher, 113, motion plate;

[0042] 12, feeding port, 13, circular ring, 14, rotating shaft, 15, filter membrane, 16, filter plate, 17, chelating resin, 18, rotating gear;

[0043] 19, transmission assembly, 191, auxiliary block, 192, straight-toothed plate, 193, fixed rod, 194, fixed plate;

[0044] 20, chelating resin loading box, 21, discharge port. DETAILED DESCRIPTION

[0045] The application will be further described below in conjunction with the accompanying drawings and embodiments.

[0046] First embodiment

[0047] Please refer to Figure 1 , wherein, Figure 1 The flowchart of the low-grade lepidolite lithium extraction method provided by the application.

[0048] The application provides a low-grade lepidolite lithium extraction method, comprising the following steps:

[0049] S1, mechanical activation pretreatment: after crushing the raw ore, the planetary ball mill is used for treatment for 2h, 0.5% sodium polyacrylate dispersant is added, and ultrasonic treatment (40kHz 30min) is performed;

[0050] S2, composite additive roasting: after mixing the ore powder, sodium sulfate and calcium fluoride, the roasting is performed in stages, the first stage: 300℃ for 1h (remove structural water), the second stage: 550℃ for 2h (main reaction stage);

[0051] Key reaction: ;

[0052] S3, selective leaching: according to the liquid-solid ratio 4:1, 5% sodium carbonate solution is added and stirred for 2h, the pH is adjusted, and the pH is maintained at 10.5-11.0 (inhibit Al 3+ , Fe 3+ hydrolysis precipitation);

[0053] Key reaction:

[0054] (pH>10 precipitate);

[0055] S4, deep purification: first remove Al (OH) 3 through a 5μm filter membrane, then adsorb the residual metal ions through chelating resin, and finally evaporate and concentrate to Li + concentration>20g / L, and cool and crystallize to obtain battery-grade lithium carbonate.

[0056] In this embodiment, the step S1 acts: the layered silicate structure of mica is destroyed through mechanical chemical action, Li + embedding sites are exposed, and the specific surface area is increased by 3-5 times.

[0057] In this embodiment, the step S2 acts: sodium sulfate reacts with Li in mica, calcium fluoride generates calcium sulfate to fix fluorine elements, and reduce environmental pollution.

[0058] In this embodiment, the step S3 acts: lithium is preferentially dissolved under alkaline conditions, and the precipitation and separation of aluminum, iron and other impurities are simultaneously realized.

[0059] The raw ore in the S1 is crushed to D50=10-50um, the rotation speed of the planetary ball mill is 300rpm, and the ball-to-material ratio is 5:1.

[0060] The mass ratio of the mineral powder in the S2, sodium sulfate and calcium fluoride is 100:25:8.

[0061] Compared with the related art, the low-grade lepidolite lithium extraction method and device provided by the application has the following beneficial effects:

[0062] After the treatment, the specific surface area of the mica is increased by 3-5 times, the contact area with the auxiliary agent and the leaching solution is greatly increased, the subsequent roasting reaction rate and lithium leaching efficiency are improved, the raw material waste is reduced, and the lithium recovery rate is improved; the double auxiliary agent is used for segmental roasting, the roasting temperature is greatly reduced compared with the traditional process, the energy consumption is greatly reduced, the production energy consumption cost is reduced, the calcium fluoride reacts with the substances generated in the reaction process (calcium sulfate is generated), the in-situ fixation of fluorine elements is realized, the fluorine pollution in the traditional process is avoided, the environmental protection emission requirements are met; the sodium sulfate can replace Li in the mica to convert lithium into a form that is easy to leach in the subsequent process, laying a foundation for high lithium leaching rate, facilitating lithium recovery, and avoiding excessive activation of aluminum, iron and other impurities in the roasting stage; most of the impurities are removed in advance through selective leaching, the treatment load of the subsequent deep purification process is reduced, the purification cost and operation complexity are reduced, the influence of impurities on the purity of lithium products is avoided, and two-stage filtration and resin adsorption can reduce the loss of lithium in the purification process, in combination with the previous process, the comprehensive lithium recovery rate is significantly improved, the waste of lithium resources is avoided, and the raw material utilization rate and economic benefits are improved.

[0063] Second embodiment

[0064] Please refer to Figures 2-10 , wherein Figure 2 is a structural schematic diagram of the low-grade lepidolite lithium extraction device provided by the application; Figure 3 is Figure 2 is a structural schematic diagram of the transmission assembly shown in the figure; Figure 4 is Figure 2 is a cross-sectional schematic diagram of the reaction kettle shown in the figure; Figure 5 is Figure 4 is an enlarged schematic diagram of part A shown in the figure; Figure 6 is Figure 4 is a structural schematic diagram of the conversion assembly shown in the figure; Figure 7 is Figure 6 is an enlarged schematic diagram of part B shown in the figure; Figure 8 is an initial state diagram of the low-grade lepidolite lithium extraction device provided by the application; Figure 9 is a motion state diagram of the low-grade lepidolite lithium extraction device provided by the application, wherein Figure 9(a) is a state diagram of the pusher after the first extension, Figure 9 (b) is a state diagram of the pusher after the second extension, Figure 9 (c) is a state diagram of the pusher after the second extension and the rotation of the driving member; Figure 10 is a state diagram of the movement of the filter membrane and the filter plate, wherein, Figure 10 (a) is a state diagram of the initial state of the filter membrane and the filter plate, Figure 10 (b) is a schematic diagram of the filter membrane and the filter plate rotating to a vertical state, Figure 10 (c) is a state diagram of the filter membrane and the filter plate rotating half a circle.

[0065] The low-grade lepidolite lithium extraction method adopts a low-grade lepidolite lithium extraction device, which comprises a box body 1 and a reaction kettle 2. Two support assemblies 3 are installed on the top of the box body 1, and the reaction kettle 2 is installed between the two support assemblies 3. A feeding chute 4 is installed on the top of the reaction kettle 2, a steam discharge pipe 5 is installed on the top of the reaction kettle 2, a discharge chute 6 is installed at the bottom of the reaction kettle 2, a rotating assembly 7 is installed in the reaction kettle 2, a sliding rod 8 is slidably connected in the rotating assembly 7, a blocking assembly 9 is installed at the bottom of the sliding rod 8, the blocking assembly 9 is used for blocking the discharge chute 6, a first driving assembly 10 is installed on the top of the reaction kettle 2, the first driving assembly 10 is used for driving the rotating assembly 7 to rotate, a second driving assembly 11 is installed on the top of the reaction kettle 2, the second driving assembly 11 is used for driving the sliding rod 8 to move vertically, a feeding port 12 is formed on the top of the box body 1, a circular ring 13 is installed on the top of the box body 1, two rotating shafts 14 are rotatably connected in the box body 1, a filter membrane 15 and a filter plate 16 are respectively installed on the outer surfaces of the two rotating shafts 14, a layer of chelating resin 17 covers the top of the filter plate 16, one end of each of the two rotating shafts 14 penetrates through the box body 1 and extends to the outside of the box body 1, and a rotating gear 18 is fixedly connected to one end of each of the two rotating shafts 14. A transmission assembly 19 is installed on one of the support assemblies 3, the transmission assembly 19 is used for driving the two rotating gears 18 to rotate, a chelating resin loading box 20 is installed on the right side of the box body 1, and a discharge port 21 is formed on the bottom of the box body 1.

[0066] In this embodiment, the feeding port 12 can be connected with the outlet of the external material conveying equipment.

[0067] Please refer to Figure 2 and Figure 3 The circular ring 13 is composed of an annular fixing ring and a plurality of inclined blocks. When the rollers 93 in the blocking assembly 9 roll on the surface thereof, the up-and-down movement can be achieved.

[0068] In other embodiments, the inner wall of the reactor 2 is provided with electric heating wires, so that the inside of the reactor 2 can be used for calcination, and the steam discharge pipe 5 can be spirally arranged on the outer surface of the feeding groove 4 to preheat the entering ore powder, thereby reducing energy consumption.

[0069] In the present embodiment, the chelating resin loading box 20 is internally provided with chelating resin 17, and the chelating resin loading box 20 is connected with the box body 1 through the feeding channel, so that new chelating resin 17 can be fed into the box body 1 after the saturated chelating resin 17 is discharged.

[0070] Please refer to Figure 9 (a), when the second driving assembly 11 is stretched to drive the sliding rod 8 to move downward, the blocking assembly 9 is moved downward, so that the discharge groove 6 is opened for discharging, and the mixed solution enters the box body 1 for purification treatment, so that the device changes from the initial reaction state to the discharging state;

[0071] Please refer to Figure 9 (b) and Figure 9 (c), by further stretching the second driving assembly 11 to drive the sliding rod 8 to move downward, the blocking assembly 9 is moved downward until it touches the ring 13, and the rotating assembly 7 is expanded to touch the inner wall of the reactor 2, at this time the first driving assembly 10 is rotated to drive the rotating assembly 7 to rotate to scrape the residual on the inner wall of the reactor 2, and the blocking assembly 9 rolls on the ring 13 to drive the reactor 2 to vibrate up and down, so that the residual sediment is shaken out, thereby changing the device from the discharging state to the cleaning state;

[0072] Please refer to Figure 9 (c), Figure 10 (a), Figure 10 (b) and Figure 10 (c), when the reactor 2 vibrates up and down, the supporting assembly 3 moves up and down, thereby indirectly moving the transmission assembly 19 up and down, so that the two rotating gears 18 reciprocate, thereby driving the filter membrane 15 and the filter plate 16 to reciprocate, so that the residual sediment and the saturated chelating resin 17 after filtration can be discharged.

[0073] Please refer to Figure 10 (a), in the initial state, the rotating shaft 14 does not rotate, so that the chelating resin 17 is on the top of the filter plate 16, when the mixed solution after reaction enters the box body 1, it is adsorbed and filtered through the filter membrane 15, the chelating resin 17 and the filter plate 16;

[0074] Please refer to Figure 10(b), when the rotating shaft 14 rotates 90°, the filter membrane 15 and the filter plate 16 are in a vertical state, so that the chelating resin 17 is discharged from the discharge port 21, and the saturated chelating resin 17 can be cleaned;

[0075] Please refer again to Figure 10 (c), when the rotating shaft 14 rotates 180°, the filter membrane 15 and the filter plate 16 are turned over, so as to facilitate backwashing and cleaning.

[0076] In the embodiment, the side wall of the box body 1 is also provided with an arc-shaped section which is in abutment with the filter membrane 15 and the filter plate 16, so as to guide the material to slide to the filter membrane 15 and the filter plate 16 for filtration without affecting the rotation of the filter membrane 15 and the filter plate 16.

[0077] Please refer again to Figure 4 The support assembly 3 comprises a support rod 31, a support block 32, a sleeve rod 33, a connecting block 34, a limiting block 35 and a first elastic member 36, the support rod 31 is fixed to the top of the box body 1, the support block 32 is fixed to the outer surface of the support rod 31, the sleeve rod 33 is sleeved on the outer surface of the support rod 31, the connecting block 34 is fixed to the outer surface of the sleeve rod 33, and the connecting block 34 is fixed to the reaction kettle 2, the limiting block 35 is fixed to the top end of the support rod 31, and the first elastic member 36 is arranged between the limiting block 35 and the connecting block 34.

[0078] In the embodiment, the first elastic member 36 comprises but is not limited to elastic structures such as springs, air pressure type telescopic cylinders, etc., as long as the connecting block 34 is provided with a rebounding force.

[0079] In the embodiment, the support block 32 is used for supporting the sleeve rod 33, and the limiting block 35 is used for limiting the connecting block 34.

[0080] The reaction kettle 2 is fixedly connected with the connecting block 34, when the reaction kettle 2 moves upward, the connecting block 34 is driven to move upward, so that the first elastic member 36 is compressed, the first elastic member 36 provides the connecting block 34 with a downward elastic force, and cooperates with the gravity to make the reaction kettle 2 stably move up and down.

[0081] Please refer again to Figure 6The rotating assembly 7 comprises a rotating rod 71, stirring blades 72, a cavity 73, a circular table 74, a fixing rod 75, a groove 76, a sliding block 77, a moving rod 78, a second elastic member 79 and scrapers 710, the rotating rod 71 is rotationally connected to the reaction kettle 2, the stirring blades 72 are installed on the rotating rod 71, the cavity 73 is formed in the rotating rod 71, the circular table 74 is installed on the outer surface of the sliding rod 8, the fixing rod 75 is installed on the rotating rod 71, the groove 76 is formed in the fixing rod 75, the sliding block 77 is slidingly connected in the groove 76, the moving rod 78 is installed on the sliding block 77, the second elastic member 79 is sleeved on the moving rod 78, and the scrapers 710 are fixed to one end of the moving rod 78.

[0082] In the embodiment, the number of the fixing rods 75, the grooves 76, the sliding blocks 77, the moving rods 78, the second elastic members 79 and the scrapers 710 is two.

[0083] In the embodiment, the second elastic member 79 comprises but is not limited to an elastic structure such as a spring, an air pressure type telescopic cylinder and the like, as long as the second elastic member 79 can provide a rebound force to the sliding block 77.

[0084] In the embodiment, when the rotating rod 71 rotates, the stirring blades 72 can be driven to rotate, and the reaction efficiency can be improved during the reaction of the material.

[0085] In the embodiment, the sliding rod 8 is slidingly connected with the rotating rod 71, and the sliding direction is a vertical direction.

[0086] In other embodiments, an anti-skid structure is arranged between the sliding rod 8 and the rotating rod 71, the anti-skid structure comprises at least one anti-skid groove and one anti-skid block, the anti-skid groove is formed in the outer surface of the sliding rod 8, the anti-skid block is fixedly connected to the rotating rod 71 and slidingly connected in the anti-skid groove, so that the sliding rod 8 can rotate together with the rotating rod 71 through the anti-skid structure without affecting the up-and-down movement of the sliding rod 8 in the rotating rod 71.

[0087] In use, the first driving assembly 10 drives the rotating rod 71 to rotate, so that the stirring blades 72 rotate to stir, when the sliding rod 8 slides downward, the circular table 74 is driven to move downward, the two moving rods 78 are pressed by the inclined surface of the circular table 74, the two moving rods 78 move away from each other, so that the two scrapers 710 move away from each other and are attached to the inner wall of the reaction kettle 2, during which the second elastic member 79 is pressed by the sliding block 77, with the rotation of the rotating rod 71, the two scrapers 710 move in a circular manner to scrape the residues and deposits on the inner wall of the reaction kettle 2;

[0088] When the sliding rod 8 slides upward, the circular table 74 moves upward and no longer presses the two moving rods 78, at this time, the second elastic member 79 will rebound and reset, so that the scraper 710 resets.

[0089] Please refer to Figure 5 , the sealing assembly 9 includes a sealing plate 91, a connecting rod 92 and a roller 93, the sealing plate 91 is fixed to the bottom end of the sliding rod 8, the connecting rod 92 is fixed to one side of the sealing plate 91, and the roller 93 is rotatably connected to the connecting rod 92.

[0090] In this embodiment, the number of connecting rods 92 and rollers 93 is two.

[0091] In this embodiment, a sealing gasket is installed on the sealing plate 91 to ensure the sealing of the sealing.

[0092] In use, when the sliding rod 8 moves downward, the sealing plate 91 moves downward, so that the discharge chute 6 is opened to discharge material, and when the sliding rod 8 continues to move downward, the sealing plate 91 continues to move downward, so that the connecting rod 92 drives the roller 93 to continue to move downward, thereby abutting in the groove of the annular ring 13, and with the first drive assembly 10 driving the rotating rod 71 to rotate, the sliding rod 8 is rotated to drive the sealing plate 91 to rotate, and then the two rollers 93 are rolled on the annular ring 13, so that the reaction kettle 2 can vibrate up and down.

[0093] Please refer to Figure 3 , the first drive assembly 10 includes a drive member 101, a worm 102 and a worm gear 103, the drive member 101 is fixed to the top of the reaction kettle 2, the worm 102 is fixed to the output shaft of the drive member 101, and the worm gear 103 is installed on the rotating rod 71.

[0094] In this embodiment, the drive member 101 includes but is not limited to a motor, a hydraulic motor and the like, as long as it can drive the worm 102 to rotate.

[0095] In this embodiment, the worm 102 is engaged with the outer surface of the worm gear 103.

[0096] In use, the drive member 101 drives the worm 102 to rotate, so that the worm gear 103 can be rotated, and the rotating rod 71 can be rotated to drive the rotating rod 71.

[0097] In other embodiments, the worm 102 and the worm gear 103 can also be in the form of a gear set, a belt pulley and a belt, a sprocket and a chain, etc.

[0098] Please refer to Figure 3The second driving assembly 11 comprises a mounting plate 111, a pushing piece 112 and a moving plate 113, the mounting plate 111 is fixed to the top of the reaction kettle 2, the pushing piece 112 is fixed to the mounting plate 111, the moving plate 113 is slidingly connected to the mounting plate 111, the output end of the pushing piece 112 is fixedly connected with the moving plate 113, and the moving plate 113 is rotationally connected with the sliding rod 8.

[0099] In the embodiment, the pushing piece 112 comprises but is not limited to a pneumatic cylinder, a hydraulic cylinder, a linear motor, an electric telescopic rod and the like, as long as the pushing piece 112 can drive the moving plate 113 to move linearly up and down.

[0100] In use, the extension of the pushing piece 112 can drive the moving plate 113 to move downwards, so that the sliding rod 8 moves downwards, and the contraction of the pushing piece 112 can drive the moving plate 113 to move upwards, so that the sliding rod 8 moves upwards, thereby achieving the function of driving the sliding rod 8 to move up and down.

[0101] Please refer to Figure 3 The transmission assembly 19 comprises an auxiliary block 191, a straight-toothed plate 192, a fixed rod 193 and a fixed plate 194, the auxiliary block 191 is slidingly connected to one side of the box body 1, the straight-toothed plate 192 is fixed to the bottom of the auxiliary block 191, the fixed rod 193 is fixed to the top of the auxiliary block 191, the fixed plate 194 is fixed to the top of the fixed rod 193, and the fixed plate 194 is fixed to the sleeve rod 33.

[0102] In the embodiment, the straight-toothed plate 192 is in mesh with the outer surfaces of the two rotating gears 18.

[0103] In the embodiment, when the reaction kettle 2 vibrates up and down, the connecting block 34 is driven to move up and down, so that the sleeve rod 33 moves up and down, and then the fixed plate 194 moves up and down, driving the fixed rod 193 to move up and down, so that the auxiliary block 191 slides up and down, driving the straight-toothed plate 192 to move up and down, and driving the two rotating gears 18 to rotate.

[0104] The working principle of the low-grade lepidolite lithium extraction method and the device thereof is as follows:

[0105] After the calcined material is added into the reaction kettle 2, sodium carbonate solution is added in proportion, the rotating assembly 7 is driven to rotate by the first driving assembly 10, and stirring and mixing reaction is carried out, and after the reaction is completed, a precipitate mixture is generated, the sliding rod 8 is driven to move downwards by the movement of the second driving assembly 11, and then the plugging assembly 9 is driven to move downwards, so that the discharge chute 6 is opened to discharge, and the mixture enters into the box body 1, and after impurities are adsorbed by the filter membrane 15 and the chelating resin 17, the mixture is discharged from the discharge port 21;

[0106] Further downward movement of the sliding rod 8 is driven by the second driving assembly 11, so that the blocking assembly 9 moves downward until it contacts the ring 13, at this time, the rotating assembly 7 is also unfolded, so that the scraper 710 contacts the inner wall of the reaction kettle 2, and the rotation of the first driving assembly 10 makes the scraper 710 move circumferentially to clean the inner wall of the reaction kettle 2, and at the same time, the roller 93 rolls on the ring 13, so that the reaction kettle 2 vibrates up and down to shake off the residual precipitate;

[0107] When the reaction kettle 2 vibrates up and down, the sleeve rod 33 moves up and down, so as to indirectly make the straight-toothed plate 192 move up and down, so as to drive the two rotating gears 18 to reciprocate, and then drive the filter membrane 15 and the filter plate 16 to reciprocate through the two rotating shafts 14, so as to discharge the precipitate left after filtration and the saturated chelating resin 17.

[0108] Compared with the related art, the low-grade lepidolite lithium extraction method and device have the following beneficial effects:

[0109] The first driving assembly 10 drives the rotating assembly 7 to rotate to realize stirring and mixing reaction, and the first movement of the second driving assembly 11 can make the blocking assembly 9 move downward, so that the device changes from the reaction state to the discharging state, and then the second movement of the second driving assembly 11 can make the rotating assembly 7 unfold, and at the same time, the blocking assembly 9 moves downward and contacts the ring 13, and the rotation of the first driving assembly 10 can make the rotating assembly 7 clean the inner wall of the reaction kettle 2 and drive the reaction kettle 2 to vibrate up and down to discharge, so that the device changes from the discharging state to the cleaning state, which facilitates the cleaning of the reaction kettle 2; At the same time of the vibration of the reaction kettle 2, the transmission assembly 19 is also linked to drive the two rotating shafts 14 to reciprocate, so that the filter membrane 15 and the filter plate 16 reciprocate, so that the precipitate left after filtration and the saturated chelating resin 17 can be discharged, which further facilitates the discharging; The present application integrates multiple functions, and through the cooperation of the first driving assembly 10 and the second driving assembly 11, the switching between multiple states is realized, and the operation is more convenient.

[0110] The above is only an embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation obtained by using the content of the specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for extracting lithium from low-grade lepidolite, characterized by, Comprise the following steps: S1, mechanical activation pretreatment: the ore is crushed and treated with a planetary ball mill for 2h, adding sodium polyacrylate dispersant, ultrasonic treatment; S2, composite additive roasting: mix the ore powder, sodium sulfate and calcium fluoride, then perform staged roasting, first stage: 300℃ for 1h, second stage: 550℃ for 2h; S3, selective leaching: add sodium carbonate solution according to liquid-solid ratio 4:1, stir for 2h, adjust pH, maintain pH=10.5-11.0; S4, deep purification: first through 5 μm filter membrane to remove Al(OH)3, then through chelating resin to adsorb residual metal ions, and finally evaporate and concentrate to Li + concentration >20 g / L, cooling crystallization to obtain battery-grade lithium carbonate.

2. The method of claim 1, wherein the lithium extraction method is characterized by, In the S1, the ore is crushed to D50=10-50μm, the rotation speed of the planetary ball mill is 300rpm, and the ball-to-material ratio is 5:

1.

3. The method of claim 1, wherein the lithium extraction method is characterized by, In the S2, the mass ratio of the ore powder, sodium sulfate and calcium fluoride is 100:25:

8.

4. The method for extracting lithium from low-grade lepidolite according to any one of claims 1-3, using a low-grade lepidolite lithium extraction device, characterized in that, The low-grade lepidolite lithium extraction device comprises a box body and a reaction kettle, two support assemblies are installed on the top of the box body, the reaction kettle is installed between the two support assemblies, a feeding chute is installed on the top of the reaction kettle, a steam discharge pipe is installed on the top of the reaction kettle, a discharging chute is installed at the bottom of the reaction kettle, a rotating assembly is installed in the reaction kettle, a sliding rod is slidably connected in the rotating assembly, a blocking assembly is installed at the bottom of the sliding rod, the blocking assembly is used for blocking the discharging chute, a first driving assembly is installed on the top of the reaction kettle, the first driving assembly is used for driving the rotating assembly to rotate, a second driving assembly is installed on the top of the reaction kettle, the second driving assembly is used for driving the sliding rod to move linearly in the vertical direction, a feeding port is formed in the top of the box body, a circular ring is installed on the top of the box body, two rotating shafts are rotatably connected in the box body, a filter membrane and a filter plate are respectively installed on the outer surfaces of the two rotating shafts, a layer of chelating resin is covered on the top of the filter plate, one end of each of the two rotating shafts penetrates through the box body and extends to the outside of the box body, a rotating gear is fixedly connected to one end of each of the two rotating shafts, a transmission assembly is installed on one of the support assemblies, the transmission assembly is used for driving the two rotating gears to rotate, a chelating resin loading box is installed on the right side of the box body, and a discharging port is formed in the bottom of the box body.

5. The method for lithium extraction from low-grade lepidolite according to claim 4, characterized in that, The support assembly comprises a support rod, a support block, a sleeve rod, a connecting block, a limiting block and a first elastic member, the support rod is fixed to the top of the box body, the support block is fixed to the outer surface of the support rod, the sleeve rod is sleeved on the outer surface of the support rod, the connecting block is fixed to the outer surface of the sleeve rod, and the connecting block is fixed to the reaction kettle, the limiting block is fixed to the top end of the support rod, and the first elastic member is arranged between the limiting block and the connecting block.

6. The method of claim 4, wherein the lithium is extracted from the low-grade lepidolite by a process comprising: The rotating component comprises a rotating rod, stirring blades, a cavity, a circular table, a fixing rod, a groove, a sliding block, a moving rod, a second elastic member and a scraper, the rotating rod is rotationally connected to the reaction kettle, the stirring blades are installed on the rotating rod, the cavity is arranged on the rotating rod, the circular table is installed on the outer surface of the sliding rod, the fixing rod is installed on the rotating rod, the groove is arranged on the fixing rod, the sliding block is slidingly connected into the groove, the moving rod is installed on the sliding block, the second elastic member is sleeved on the moving rod, and the scraper is fixed to one end of the moving rod.

7. The method of claim 4, wherein the lithium concentration is 0.1% or more. The blocking component comprises a blocking plate, a connecting rod and a roller, the blocking plate is fixed to the bottom end of the sliding rod, the connecting rod is fixed to one side of the blocking plate, and the roller is rotationally connected to the connecting rod.

8. The method of claim 6, wherein the lithium extraction method is characterized by, The first driving component comprises a driving member, a worm and a worm wheel, the driving member is fixed to the top of the reaction kettle, the worm is fixed to the output shaft of the driving member, and the worm wheel is installed on the rotating rod.

9. The method of claim 4, wherein the lithium concentration is 0.1% or more. The second driving component comprises a mounting plate, a pushing member and a moving plate, the mounting plate is fixed to the top of the reaction kettle, the pushing member is fixed to the mounting plate, the moving plate is slidingly connected to the mounting plate, the output end of the pushing member is fixedly connected to the moving plate, and the moving plate is rotationally connected to the sliding rod.

10. The method of claim 5, wherein the lithium extraction method is characterized by, The transmission component comprises an auxiliary block, a straight-toothed plate, a fixing rod and a fixing plate, the auxiliary block is slidingly connected to one side of the box, the straight-toothed plate is fixed to the bottom of the auxiliary block, the fixing rod is fixed to the top of the auxiliary block, the fixing plate is fixed to the top of the fixing rod, and the fixing plate is fixed to the sleeve rod.

Images