A production method and device for preparing battery-grade lithium carbonate by continuous lithium precipitation

Abstract

The application provides a production method and device for continuously preparing battery-grade lithium carbonate by lithium precipitation. The production method comprises the following steps: S1: preparing a lithium-containing solution, brine prepared from a lithium ore is purified and impurities are removed by a resin to obtain the lithium-containing solution, and then the lithium-containing solution is loaded into a container and heated to above 95 DEG C by a water bath for standby; S2: preparing a carbonate solution; S3: continuously precipitating lithium; and S4: filtering and washing with water. The production method for continuously preparing battery-grade lithium carbonate by lithium precipitation provided by the application pumps the solution required for lithium precipitation into a micro-pipe jet flow high-shear mixer by an external peristaltic pump and the like to generate lithium carbonate slurry through reaction, and then the particle size of the lithium carbonate is controlled through multiple shear layers inside the micro-pipe jet flow high-shear mixer, and then the lithium carbonate flows into a collector through an outlet below to age, so that the problem of peritectic existing in lithium carbonate production is reduced, the impurity content is reduced, and the purpose of continuously precipitating battery-grade lithium carbonate is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of lithium carbonate preparation, in particular to a production method and device for preparing battery-grade lithium carbonate by continuous lithium precipitation. BACKGROUND

[0002] Lithium carbonate is an important raw material for lithium-ion battery cathode materials, and its purity directly affects the performance of the battery. Currently, the main method for producing lithium carbonate in industry is intermittent precipitation method, which has problems such as low production efficiency, high energy consumption, and unstable product quality.

[0003] At present, the representative schemes of the method for preparing battery-grade lithium carbonate by continuous lithium precipitation mainly include the following:

[0004] First, in the prior art, Chinese invention patent CN107540005A discloses a continuous lithium precipitation device and a matching production process. This technical scheme effectively breaks through the limitations of traditional intermittent production mode and secondary lithium precipitation process by introducing a continuous lithium precipitation device, and makes significant progress in improving production efficiency. Specifically, the process optimization realizes three key improvements: first, the original step-by-step operation is integrated into a continuous process, which greatly reduces the process steps; second, the unit time capacity is significantly improved through equipment improvement; third, the equipment investment and raw material consumption cost are effectively saved. However, experimental verification shows that this scheme still has design defects in the material mixing link: the distance between the sodium carbonate solution introduction port and the concentrated lithium sulfate purification liquid injection point is too large, and a staged addition method is used. The double effects of spatial isolation and time difference make it difficult for the two reaction media to be quickly and uniformly mixed. In actual operation, local agglomeration phenomenon is easy to occur, which reduces the solid-liquid contact area and causes incomplete chemical reaction, etc., ultimately leading to quality problems such as uneven product particle size distribution and irregular crystal morphology.

[0005] In another prior art, Chinese patent CN110963512A proposes a continuous preparation method of battery-grade lithium carbonate. The technical solution adopts lithium chloride raw material liquid for multi-stage purification treatment, especially introduces ethylenediaminetetraacetic acid disodium (EDTA-2Na) solution for deep removal of calcium ions, and then implements continuous synthesis with sodium carbonate auxiliary materials in a multi-stage reaction system. The innovation points mainly lie in three aspects: ①Through the distributed feeding system cooperating with the bidirectional circulating mixing mechanism, the dynamic balance of the reaction system is realized; ②The precise control of material flux technology is adopted to ensure the stable control of the solid-liquid interface in the reaction kettle; ③The continuous production mode is constructed to improve the product yield to the industrial grade standard. The actual application shows that the process has the technical advantages of simple and efficient process flow, significantly reduced operation cost, etc., especially in the industrialization amplification process, it shows good economic indicators, and the product purity standard rate can reach more than 98.5%. However, it should be noted that there is a chelating agent residue problem in the implementation process of the technical solution - the added EDTA complexing agent can effectively improve the removal efficiency, but the subsequent treatment faces two technical bottlenecks: one is that the post-treatment process of the chelating agent residue is complex, and a special separation device needs to be additionally configured.

[0006] Therefore, it is necessary to provide a production method and device for preparing battery-grade lithium carbonate by continuous lithium precipitation to solve the above technical problems. SUMMARY

[0007] The present application provides a production method and device for preparing battery-grade lithium carbonate by continuous lithium precipitation, which solves the problem that the current production process adopts a staged addition method, which causes the two reaction media to be difficult to mix uniformly and quickly due to the dual effects of spatial isolation and time difference.

[0008] To solve the above technical problems, the production method for preparing battery-grade lithium carbonate by continuous lithium precipitation provided by the present application comprises the following steps:

[0009] S1: Prepare a lithium-containing solution. Brine obtained from lithium ore is purified and impurities are removed by resin to obtain a lithium-containing solution, which is then loaded into a container and heated to above 95℃ by water bath for standby;

[0010] S2: Prepare a carbonate solution. A carbonate solution with a concentration of 320-360 g / L is prepared, and then loaded into a container and heated to above 95℃ by water bath for standby;

[0011] S3: Continuous lithium precipitation. Open the micro-pipe jet flow high-shear mixer and set a certain working speed. The lithium-containing solution and the carbonate solution are pumped into the micro-pipe jet flow high-shear mixer at a certain flow rate by peristaltic pumps to mix and generate lithium carbonate and control the particle size by shearing. The pumping speed of the lithium-containing solution is set, and the pumping speed of the carbonate solution is calculated according to the formula:

[0012] v(Na2CO3) = p(Li+) x v(Li+) x l x 106 / 13.88 x p(Na2CO3);

[0013] wherein v is flow rate, unit mL / min, p is mass concentration, unit g / L, and l is carbonate excess coefficient; the lithium carbonate slurry is collected by a beaker and placed in a water bath for aging for not less than 1 h;

[0014] S4: hot filtration and water washing, the lithium carbonate slurry in S3 is subjected to hot filtration and solid-liquid separation, then lithium carbonate solids are added into deionized water at a preset solid-liquid ratio, stirred for 10 min, and subjected to filtration, and the above water washing is repeated for 2-5 times, wherein a small amount of solid sample is taken each time and placed in a muffle furnace for drying for 2 h, and the drying temperature is 260℃.

[0015] Preferably, the lithium-containing solution comprises one or more of post-resin brine or post-resin concentrated brine after three-stage preheating.

[0016] Preferably, the micro-tube jet flow high-shear mixer has a shear rotation speed of 900-1800 rpm.

[0017] Preferably, the brine flow rate is 5-100 mL / min, and the carbonate flow rate is 1-20 mL / min.

[0018] Preferably, in S4, the solids are added into deionized water at a temperature above 95℃ at a solid-liquid ratio of 1:3.5 (mass ratio), stirred for 10 min, and subjected to filtration.

[0019] The application also provides a production device for continuously preparing battery-grade lithium carbonate by lithium precipitation, which is used in the production method for continuously preparing battery-grade lithium carbonate by lithium precipitation, and comprises a cleaning device, wherein the cleaning device comprises a support, a stirring device, a filter cartridge, a cleaning cartridge, a lifting platform, a mounting arm, and a storage barrel.

[0020] The lifting platform is installed on the support, the stirring device is installed on the lifting platform, the lifting platform is used for lifting the stirring device, the filter cartridge is installed on the support, one end of the mounting arm is installed on the lifting platform, one end of the cleaning cartridge is located in the filter cartridge, the other end of the cleaning cartridge is detachably connected to the other end of the mounting arm, and the stirring blade of the stirring device is located in the interior of the cleaning cartridge.

[0021] The cleaning cartridge comprises a cartridge body and a first filter element, and the first filter element is detachably installed at the bottom of the cartridge body.

[0022] The bottom end of the filter cartridge is in communication with the storage barrel through a valve and a liquid outlet pipe in sequence.

[0023] Preferably, the cleaning barrel further comprises a second filter element, the second filter element is located between the first filter element and the barrel body, and the filter hole diameter of the second filter element is greater than the particle size of lithium carbonate.

[0024] Preferably, the cleaning device further comprises a connecting pin and a threaded pin, a square sleeve and a threaded sleeve are arranged at the bottom of the barrel body, the threaded pin is sequentially threaded through the first filter element and the second filter element and then is screwed with the threaded sleeve, the connecting pin is threaded through the square sleeve, a top cap is arranged at the top end of the connecting pin, a square part is arranged on the connecting pin below the top cap, the square part has the same size as the inner cavity of the square sleeve, the first filter element and the second filter element are sleeved on the connecting pin and below the square sleeve, and the first filter element is fixedly connected with the connecting pin.

[0025] Preferably, the cleaning device further comprises a vibration structure, when the cleaning barrel is removed from the filter cartridge, the vibration structure is used to drive the cleaning barrel to reciprocatingly vibrate, and the cleaning barrel is slidably arranged on the mounting arm.

[0026] Preferably, the vibration structure comprises a driving shaft and a cam, a cylindrical groove is arranged at the bottom end of the stirring shaft in the stirring device, one end of the driving shaft is arranged in the cylindrical groove, a driving pipe is arranged at the center of the second filter element, an oval cavity and a circular cavity are arranged at the top end and the bottom end of the driving pipe respectively, the oval cavity and the circular cavity are communicated, and the other end of the driving shaft is threaded through the oval cavity and extends into the circular cavity and then is communicated with the cam.

[0027] Compared with the related art, the production method and device for continuously preparing battery-grade lithium carbonate by lithium precipitation have the following beneficial effects:

[0028] The production method and device for continuously preparing battery-grade lithium carbonate by lithium precipitation provided by the application can pump the solution required for lithium precipitation into a micro-pipe jet flow high-shear mixer through an external peristaltic pump and the like to generate lithium carbonate slurry through reaction, control the particle size of the lithium carbonate through a plurality of shear layers in the micro-pipe jet flow high-shear mixer, and then flow into a collector through a lower outlet to age, so as to reduce the problem of peritectic existing in the production of lithium carbonate and reduce the impurity content, thereby achieving the purpose of continuously precipitating battery-grade lithium carbonate. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The steps of the production method for continuously preparing battery-grade lithium carbonate by lithium precipitation provided by the application are shown in a step block diagram.

[0030] Figure 2 The structure of the cleaning device in the production device for continuously preparing battery-grade lithium carbonate by lithium precipitation provided by the application is shown in a structure diagram.

[0031] Figure 3Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Figure 1 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2.

[0032] Figure 4 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2.

[0033] Figure 5 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2.

[0034] Figure 6 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Figure 5 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2.

[0035] Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Figure 7 (a) is a schematic view of the stirring device stirring the lithium carbonate solid particles in deionized water for cleaning, Figure 7 (b) is a schematic view of the lifting platform separating the cleaned lithium carbonate solid particles from the deionized water by lifting the cleaning cylinder through the mounting arm; Figure 7

[0036] Figure 8 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2.

[0037] Figure 9 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Figure 8 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2.

[0038] Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Figure 10 Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2.

[0039] Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2. Another perspective view of the cleaning device shown in Fig. 1 is shown in Fig. 2.

[0040] 1, support platform;

[0041] 2, stirring device; 21, motor; 22, stirring shaft; 23, stirring blade; 221, cylindrical groove;

[0042] 3, filter cylinder; 31, support ring;

[0043] 4, cleaning cylinder; 41, cylinder body; 42, second filter; 43, first filter; 44, driving pipe;

[0044] 411, threaded sleeve; 412, square sleeve; 413, mounting groove; 414, sliding block; 421, flange; 431, mounting frame; 432, filter membrane;

[0045] 441, elliptical cavity; 442, circular cavity;

[0046] 5, lifting platform; 51, lifting cylinder; 52, assembly plate; 53, telescopic arm;

[0047] 6, mounting arm; 611, spring; 612, assembling groove;

[0048] 7, vibration structure; 71, driving shaft; 72, cam;

[0049] 8, threaded pin;

[0050] 9, connecting pin; 91, top hat; 92, square part;

[0051] 10, storage barrel; 20, liquid outlet pipe; 30, valve. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0053] The present application provides a production method for preparing battery-grade lithium carbonate by continuous lithium precipitation.

[0054] Please refer to Figure 1 In an embodiment of the present application, the production method for preparing battery-grade lithium carbonate by continuous lithium precipitation comprises the following steps:

[0055] S1: preparing a lithium-containing solution, brine prepared from lithium ore is purified and impurities are removed by resin to obtain a lithium-containing solution, and then the lithium-containing solution is loaded into a container and heated to above 95 DEG C by water bath for standby;

[0056] S2: preparing a carbonate solution, a carbonate solution of 320-360 g / L is prepared, and then the carbonate solution is loaded into a container and heated to above 95 DEG C by water bath for standby;

[0057] S3: continuously precipitating lithium, opening the micro-tube jet flow high shear mixer and setting a certain working speed, pumping the above-mentioned lithium-containing solution and carbonate solution into the micro-tube jet flow high shear mixer at a certain flow rate by peristaltic pump to mix and generate lithium carbonate and shear control particle size, wherein the pumping speed of the lithium-containing solution is set, and the pumping speed of the carbonate solution is calculated according to the formula:

[0058] v(Na2CO3) = p(Li+) x v(Li+) x l x 106 / 13.88 x p(Na2CO3);

[0059] Wherein v is the flow rate, unit mL / min, p is the mass concentration, unit g / L, l is the carbonate excess coefficient; collecting the lithium carbonate slurry in a beaker and placing it in a water bath for stirring and aging in a water bath for not less than 1 h;

[0060] S4: hot filtration and washing, the lithium carbonate slurry in S3 is separated by hot filtration, and then the lithium carbonate solid is added into deionized water according to a preset solid-liquid ratio, stirred for 10 min, and then filtered by suction. The above washing is repeated for 2-5 times, and a small amount of solid sample is taken from each time and placed in a muffle furnace for drying for 2 h, and the drying temperature is 260°C.

[0061] The solution required for lithium precipitation is pumped into the micro-tube jet flow high shear mixer by an external peristaltic pump and the like to react to produce lithium carbonate slurry, and then the lithium carbonate particle size is controlled through multiple shear layers inside the micro-tube jet flow high shear mixer, and then flows into the collector through the lower outlet to age, reduces the problem of peritectic existing in lithium carbonate production and reduces the impurity content, so as to achieve the purpose of continuous precipitation of battery-grade lithium carbonate.

[0062] As a preferred mode of the embodiment, the lithium ore is one or more of spodumene, lepidolite, petalite, and eucolite

[0063] As a preferred mode of the embodiment, the lithium-containing solution includes one or more of resin post-brine or concentrated brine after three-stage preheating.

[0064] As a preferred mode of the embodiment, the brine concentration is 5-40 g / L; the carbonate concentration is 200-400 g / L; the main components of the brine are one or more of lithium chloride, lithium sulfate, or lithium hydroxide, and the main components of the carbonate solution are one or more of sodium carbonate or potassium carbonate;

[0065] As a preferred mode of the embodiment, the carbonate excess coefficient is 0.5-1.5, and in the embodiment, it is set to 1.1.

[0066] As a preferred mode of the embodiment, the shear rotation speed of the micro-tube jet flow high shear mixer is 900-1800 rpm.

[0067] As a preferred mode of the embodiment, the brine flow rate is 5-100 mL / min, and the carbonate flow rate is 1-20 mL / min.

[0068] As a preferred mode of the embodiment, in S4, the solid is added into deionized water according to a solid-liquid ratio of 1:3.5 (mass ratio), stirred for 10 min, and then filtered by suction.

[0069] As an optional mode of the embodiment, S1: preparation of the lithium-containing solution, the brine prepared from lepidolite is purified, resin impurities are removed, and concentrated brine is obtained after three-stage preheating, and the main substance is lithium sulfate, wherein Li + The concentration is ≥18 g / L, which is loaded into a beaker and placed in a water bath for heating to above 95°C for standby.

[0070] At this time, the operating speed of the microtube jet high-shear mixer in S3 is 1200 rpm or 1500 rpm. When the operating speed is 1200 rpm, the lithium sulfate solution is pumped in at a rate of 10 mL / min or 20 mL / min. When the operating speed is 1500 rpm, the lithium sulfate solution is pumped in at a rate of 20 mL / min.

[0071] In another optional way of this embodiment, the lithium-containing solution is prepared by purifying the brine obtained from lepidolite and removing impurities with resin to obtain resin-treated brine, the main substance of which is lithium sulfate; the brine is placed in a beaker and heated to above 95°C in a water bath for later use.

[0072] In this embodiment, Li + Concentration ≥6g / L or Li + Concentration ≥20g / L or Li + Concentration ≥28g / L;

[0073] The microtube jet high-shear mixer operates at a speed of 1500 rpm;

[0074] When Li + When the concentration is ≥6g / L, the corresponding lithium sulfate solution pumping rate is 50mL / min;

[0075] Li + Concentration ≥20g / L or Li + When the concentration is ≥28g / L, the corresponding lithium sulfate solution pumping rate is 20mL / min.

[0076] The present invention also provides a production apparatus for the continuous lithium deposition process to prepare battery-grade lithium carbonate.

[0077] Please see Figure 2 and Figure 4 A production apparatus for the continuous lithium deposition process to prepare battery-grade lithium carbonate, used in the production method of the continuous lithium deposition process to prepare battery-grade lithium carbonate, includes: a cleaning device, the cleaning device including a support 1, a stirring device 2, a filter cartridge 3, a cleaning cartridge 4, a lifting platform 5, an installation arm 6, and a storage tank 10.

[0078] The lifting platform 5 is installed on the support 1, the stirring device 2 is installed on the lifting platform, the lifting platform is used to lift the stirring device 2, the filter cylinder 3 is installed on the support 1, one end of the mounting arm 6 is installed on the lifting platform 5, one end of the cleaning cylinder 4 is located inside the filter cylinder 3, the other end of the cleaning cylinder 4 is detachably connected to the other end of the mounting arm 6, and the stirring blade 23 of the stirring device 2 is located inside the cleaning cylinder 4.

[0079] The cleaning cylinder 4 includes a cylinder body 41 and a first filter element 43, the first filter element 43 being detachably installed at the bottom of the cylinder body 41;

[0080] The bottom end of the filter cartridge 3 is communicated with the storage barrel 10 through the valve 30 and the liquid outlet pipe 20 in sequence.

[0081] In the embodiment, the cleaning device is mainly used for the water washing and stirring of the lithium carbonate solid in the deionized water in step S4 for 10 minutes, and the above water washing is repeated for 2-5 times; in the step, the water washing is mainly used for removing the impurity ions, such as sulfate ions, chloride ions and sodium ions, attached to the lithium carbonate solid.

[0082] Due to the existing filter equipment, after washing, the storage barrel is vacuumized by a vacuum pump, the liquid in the filter cartridge 3 is quickly discharged by negative pressure, the solid is filtered by the first filter piece 43, and the cleaning liquid passes through the lithium carbonate solid again when flowing out, so that the impurity ions in the liquid are easily attached to the lithium carbonate solid again, thereby causing poor cleaning effect and requiring more cleaning times.

[0083] In the embodiment, the lithium carbonate solid to be cleaned is placed in the cleaning cartridge 4 and deionized water is added, at this time the valve 30 is closed, the stirring device 2 stirs and cleans the lithium carbonate solid for a preset time, then the lifting platform 5 lifts the stirring device 2, and the installation arm 6 drives the cleaning cartridge 4 to move up at the same time, in the moving process, the stirring device 2 continues to stir and clean, the cleaned deionized water gradually separates from the lithium carbonate solid in the cleaning cartridge 4, such as Figure 7 When the lithium carbonate solid is completely separated from the deionized water, the valve 30 is opened, the deionized water enters the storage barrel 10 through the liquid outlet pipe 20, and then the lifting platform 5 is lowered, the cleaning cartridge 4 enters the inside of the filter cartridge 3 again, and then the deionized water is added, and the cleaning is repeated for multiple times;

[0084] By moving the lithium carbonate solid up to separate from the deionized water first, and continuously stirring by the stirring device 2 in the moving process, after the lithium carbonate solid is completely separated from the deionized water, the deionized water is discharged, so that the impurities in the water can be greatly reduced from being attached to the lithium carbonate solid again due to the deionized water being discharged first, thereby affecting the cleaning efficiency.

[0085] Please refer to Figure 1 In the embodiment, the storage barrel 10 is located below the cleaning cartridge 4, and the deionized water can automatically flow into the inside of the storage barrel 10 through the liquid outlet pipe 20;

[0086] Of course, a vacuum pump can also be provided, which is communicated with the storage barrel 10 through a pipeline; the gas in the storage barrel 10 is pumped out to generate negative pressure, so that the deionized water in the filter cartridge 3 can quickly enter the storage barrel 10, or when the placement height of the storage barrel 10 is not lower than the filter cartridge 3, the gas in the storage barrel 10 is pumped out by the vacuum pump, and the deionized water is quickly discharged into the storage barrel 10 by the negative pressure.

[0087] The bottom side of the storage bucket 10 is communicated with a drain pipe, and a valve is arranged on the drain pipe to facilitate the discharge of the collected deionized water.

[0088] The inside of the filter cylinder 3 is provided with a supporting ring 31 for supporting the cleaning cylinder 4.

[0089] Please refer to Figure 3 In the embodiment, the lifting platform 5 includes a lifting cylinder 51, an assembly plate 52, and two telescopic arms 53. The lifting cylinder 51 is installed on the support platform 1, the two telescopic arms 53 are installed on the support platform 1 and located on the two sides of the lifting cylinder 51, and the assembly plate 52 is installed on the output end of the lifting cylinder 51 and the telescopic end of the two telescopic arms 53.

[0090] The motor 21 of the stirring device 2 is installed on the assembly plate 52, and the number of the installation arms 6 is preferably two, which are installed on the two sides of the assembly plate 52.

[0091] The assembly plate 52 is lifted by the lifting cylinder 51, so as to drive the assembly plate 52 and the installation arms 6 to lift.

[0092] The lifting cylinder 51 can be a pneumatic cylinder or a hydraulic cylinder or an electric push rod, etc. The telescopic arm 53 includes a supporting arm and a guide rod. The supporting arm is installed on the support platform 1, and the guide rod is slidably installed in the supporting arm at one end and connected with the assembly plate 52 at the other end.

[0093] The stirring device 2 includes a motor 21, a stirring shaft 22, and stirring blades 23. The stirring shaft 22 is connected with the output end of the motor 21 and the stirring blades 23. In the embodiment, two groups of stirring blades 23 are arranged on the stirring shaft 22 in an up-down manner, and each group of stirring blades 23 includes two stirring blades arranged in a symmetrical manner.

[0094] Please refer to Figure 4 and 5 As a preferred mode of the embodiment, the cleaning cylinder 4 further includes a second filter 42 located between the first filter 43 and the cylinder body 41. The filter hole diameter of the second filter 42 is greater than the particle size of the lithium carbonate solid particles.

[0095] By arranging the second filter 42, the raw material impurities such as large solid particles that are not completely reacted may be filtered out of the lithium carbonate solid particles. That is, the first filter 43 removes the impurity ions smaller than the lithium carbonate solid particles, and the second filter 42 is used to filter the large-particle impurities, further improving the purity of the lithium carbonate solid particles.

[0096] First, the lithium carbonate solid particles are filtered for large-particle impurities. When filtering, the installation arms 6 are lifted by the lifting platform 5, so that the cleaning cylinder 4 is moved out of the filter cylinder 3, as shown in Figure 8The first filter 43 is staggered with the second filter 42, that is, staggered with the bottom and the cleaning cylinder 4, and the lithium carbonate solid particles are added into the cleaning cylinder 4, the lithium carbonate solid particles enter the receiving container placed in advance below the cleaning cylinder 4 through the second filter 42, then the cleaning cylinder 4 is disassembled, the impurities filtered in the cleaning cylinder 4 are poured out, and then the lithium carbonate solid particles are added into the cleaning cylinder 4 and added into the deionized water to clean the impurities.

[0097] After subsequent cleaning, the first filter 43 and the second filter 42 are separated, and the cleaned lithium carbonate solid is discharged from the cleaning cylinder 4.

[0098] Please refer to Figure 6 The first filter 43 comprises a mounting frame 431 and a filter membrane 432, the top of the mounting frame 431 is provided with a circular groove, the filter membrane 432 is arranged in the circular groove, and the bottom of the mounting frame 431 is provided with a plurality of holes through which the deionized water is discharged after passing through the filter membrane 432.

[0099] The second filter 42 is a filter plate, and a filter hole is arranged on the filter plate, and the diameter of the filter hole is greater than that of the lithium carbonate solid particles.

[0100] The second filter 42 can also be arranged in the same way as the first filter 43.

[0101] The top of the mounting frame 431 is attached to the bottom of the second filter 42, and the filter membrane 432 is limited in the vertical direction.

[0102] When the first filter 43 is separated from the second filter 42, the filter membrane 432 is convenient to assemble or disassemble.

[0103] Please refer to Figure 6 As an optional way of the embodiment, the cleaning device further comprises a connecting pin 9 and a threaded pin 8, a square sleeve 412 and a threaded sleeve 411 are arranged at the bottom of the cylinder body 41 in a spaced manner, the threaded pin 8 is sequentially threaded through the first filter 43 and the second filter 42 and then is screwed with the threaded sleeve 411, the connecting pin 9 is threaded through the square sleeve 412, the top end of the connecting pin 9 is provided with a top cap 91, a square part 92 is arranged on the connecting pin 9 below the top cap 91, the square part 92 has the same size as the inner cavity of the square sleeve 412, the first filter 43 and the second filter 42 are sleeved on the connecting pin 9 and located below the square sleeve 412, and the first filter 43 is fixedly connected with the connecting pin 9.

[0104] When it is needed to stagger the first filter 43 and the second filter 42, the threaded pin 8 can be unscrewed, then the connecting pin 9 is rotated to drive the first filter 43 to rotate, so that the first filter 43 is separated from and staggered with the second filter 42, as shown in Figure 8Then, the connecting pin 9 is moved downward to be inserted into the square part 92 and inserted into the square sleeve 412 to be axially limited. Subsequently, the threaded pin 8 can be screwed with the threaded sleeve 411 again to support the second filter element 42, so as to separate the first filter element 43 and the second filter element 42.

[0105] When the square part 92 is inserted into the square sleeve 412, the top cap 91 is located at the top of the square sleeve 412, which is supported by the square sleeve 412, thereby limiting the connecting pin 9 in the vertical direction.

[0106] Preferably, a plurality of threaded sleeves 411 and threaded pins 8 are provided, and three are provided in the embodiment, which are arranged around the cleaning barrel 4. By providing a plurality of threaded sleeves 411 and threaded pins 8, the first filter element 43 and the second filter element 42 are limited from multiple positions, which improves the stability of the limiting, and the bottom of the barrel body 41 is provided with a mounting groove 413 corresponding to the positions of the threaded sleeve 411 and the square sleeve 412, which is used to mount the threaded sleeve 411 and the square sleeve 412.

[0107] Corresponding threaded pins 8 and connecting pins 9 are provided on the first filter element 43 and the second filter element 42.

[0108] As another optional way of the embodiment, the connecting pin 9 can be cancelled, and the connecting pin 9 and the square sleeve 412 are replaced by the threaded pin 8 and the threaded sleeve 411. When separating the first filter element 43 and the second filter element 42, the threaded pin 8 is sequentially disassembled, the first filter element 43 is disassembled, and then the threaded pin 8 is mounted to support the second filter element 42.

[0109] Please refer to Figure 5 and Figure 6 As an optional way of the embodiment, the cleaning device further comprises a vibration structure 7, which is used to drive the cleaning barrel 4 to reciprocatingly vibrate when the cleaning barrel 4 is moved out of the filter cartridge 3, and the cleaning barrel 4 is slidably mounted on the mounting arm 6.

[0110] By providing the vibration structure 7, when large impurities are filtered from the lithium carbonate solid or the cleaning barrel 4 is discharged after subsequent cleaning, the vibration structure 7 drives the cleaning barrel 4 to reciprocatingly vibrate, so that the lithium carbonate particles can be quickly and uniformly discharged from the second filter element 42.

[0111] Please refer to Figure 4 and Figure 5As a preferred manner of the embodiment, the mounting arm 6 is provided with a mounting groove 612 at one end away from the mounting plate 52, a spring 611 is mounted in the mounting groove 612, and two sliding blocks 414 are correspondingly mounted on the two sides of the cleaning cylinder 4, the bottom of each sliding block 414 is provided with a pulley, when the cleaning cylinder 4 is mounted on the mounting arm 6, the two sliding blocks 414 are correspondingly placed in the two mounting grooves 612, the pulley abuts against the groove wall of the mounting groove 612, and the end of the sliding block 414 abuts against the spring 611, so that the cleaning cylinder 4 can be slidably connected to the mounting arm 6.

[0112] When disassembling, the cleaning cylinder 4 is slightly lifted to move the sliding blocks 414 out of the mounting grooves 612, then the cleaning cylinder 4 is rotated to misalign the sliding blocks 414 with the mounting arm 6, and then the cleaning cylinder 4 is lowered to separate from the stirring shaft 22. Of course, when disassembling, the lifting platform 5 first lifts the stirring device 2 to move out of the filter cylinder 3.

[0113] When the subsequent cleaning cylinder 4 vibrates, the spring 611 can play a buffering role to improve the stability of the vibration of the cleaning cylinder 4. The mounting groove 612 is provided with a guide column, and the spring 611 is sleeved on the guide column to guide and limit the expansion of the spring 611. There is a space between the guide column and the sliding block 414.

[0114] Please refer to Figure 5 and Figure 6 again, as an optional manner of the embodiment, the vibration structure 7 includes a driving shaft 71 and a cam 72, a cylindrical groove 221 is formed at the bottom end of the stirring shaft 22 in the stirring device 2, one end of the driving shaft 71 is mounted in the cylindrical groove 221, a driving pipe 44 is mounted at the center of the second filter 42, an oval cavity 441 and a circular cavity 442 are respectively formed at the top end and the bottom end of the driving pipe 44, the oval cavity 441 and the circular cavity 442 are communicated, the other end of the driving shaft 71 penetrates through the oval cavity 441 and extends into the circular cavity 442 to communicate with the cam 72.

[0115] The diameter of the circular cavity 442 is greater than or equal to the long diameter of the oval cavity 441.

[0116] When the lithium carbonate solid is cleaned of impurity ions, at this time the cam 72 is located in the circular cavity 442, when the motor 21 drives the stirring shaft 22 to rotate the stirring blade 23, the stirring blade 23 drives the lithium carbonate to rotate in the deionized water for cleaning, the stirring shaft 22 drives the cam 72 to rotate through the driving shaft 71, and the cam 72 does not act on the driving pipe 44, so that the driving pipe 44 generates a horizontal force;

[0117] When the lithium carbonate solid is filtered or discharged, the threaded pin 8 is unscrewed in sequence, the rotating connecting pin 9 drives the first filter piece 43 to rotate 180 degrees and the second filter piece 42 is staggered, then the connecting pin 9 moves down the first filter piece 43 to make the square part 92 of the connecting pin 9 inserted into the square sleeve 412, at this time, the first filter piece 43 moves down, so that the second filter piece 42 moves down, the second filter piece 42 is sleeved on the connecting pin 9 and supported on the first filter piece 43, then the threaded pin 8 is reinstalled to support the second filter piece 42, when the second filter piece 42 moves down, the pipe 44 moves down, the cam 72 enters the elliptical cavity 441 from the circular cavity 442, when the motor 21 drives the stirring shaft 22 to rotate, the driving shaft 71 drives the cam 72 to rotate and act on the narrow inner wall of the elliptical cavity 441, the second filter piece 42 drives the entire cleaning cylinder 4 to reciprocate and vibrate, realizing the function of vibrating discharge; at this time, the stirring shaft 22 drives the stirring blade 23 to rotate, which can assist the discharge of lithium carbonate solid particles.

[0118] Thus, the stirring device 2 can realize stirring and cleaning of lithium carbonate solid in one state, and driving the vibration structure 7 to reciprocate the cleaning cylinder 4 in another state, realizing fast and uniform discharge, and realizing the switching of the two states in the process of switching the first filter piece 43 and the second filter piece 42.

[0119] When the second filter piece 42 is a filter plate, the pipe 44 is installed on the center of the first filter piece 43; when the second filter piece 42 is the same as the first filter piece 43, the pipe 44 is installed on the installation frame 431 of the second filter piece 42, and a center hole is formed in the center of the filter membrane 432 to be sleeved on the pipe 44.

[0120] Please refer to Figure 4 In the embodiment, the second filter piece 42 is provided with a flange 421, which is attached to the inner wall of the cleaning cylinder 4, when the second filter piece 42 moves down, the flange 421 still remains attached to the inner wall of the cylinder body 41, avoiding the gap between the second filter piece 42 and the cylinder body 41, and the lithium carbonate solid shell flows out through the gap;

[0121] When the cleaning cylinder 4 is installed with the installation arm 6, the stirring shaft 22 is sleeved on the pipe 44 through the cylindrical groove 221 at the bottom end, so as to avoid the deionized water driving the lithium carbonate solid particles into the pipe 44. The pipe 44 has a spacing that can slide up and down.

[0122] Preferably, a sealing ring can be provided at the top end of the pipe 44, and the outer wall of the sealing ring is attached to the inner wall of the cylindrical groove 221, which can ensure the sealing.

[0123] Wherein, the stirring device 2 works to stop the stirring shaft 22 to rotate an integer right, so that the cam 72 can be aligned with the long diameter of the oval cavity 441, so that the cam 72 can be removed from the driving pipe 44.

[0124] Wherein, the continuous lithium precipitation preparation battery grade lithium carbonate production device comprises a micro-tube jet flow high shear mixer, a peristaltic pump, a water bath heating device, a muffle furnace and the like in addition to the cleaning device.

[0125] The working principle of the continuous lithium precipitation preparation battery grade lithium carbonate production device provided by the application is as follows:

[0126] The large-particle impurities in the lithium carbonate solid particles are filtered, and during the filtering, the lifting platform 5 first lifts the mounting arm 6 to move the cleaning cylinder 4 out of the filter cylinder 3, as shown in Figure 8 The first filter 43 is staggered with the second filter 42, that is, the cleaning cylinder 4 is staggered with the bottom, the lithium carbonate solid particles are added into the cleaning cylinder 4, the lithium carbonate solid particles pass through the second filter 42 into the receiving container placed in advance below the cleaning cylinder 4, and then the cleaning cylinder 4 is disassembled, and the filtered impurities in the cleaning cylinder 4 are poured out.

[0127] The lithium carbonate solid to be cleaned is placed in the cleaning cylinder 4 and deionized water is added, at this time the valve 30 is closed, the stirring device 2 stirs and cleans the lithium carbonate solid for a preset time, then the lifting platform 5 lifts the stirring device 2, and the mounting arm 6 drives the cleaning cylinder 4 to move up at the same time, in the process of moving up, the stirring device 2 continues to stir and clean, and the cleaned deionized water gradually separates from the lithium carbonate solid in the cleaning cylinder 4, as shown in Figure 7 When the lithium carbonate solid is completely separated from the deionized water, the valve 30 is opened, the deionized water enters the storage barrel 10 through the liquid outlet pipe 20, and then the lifting platform 5 is lowered, the cleaning cylinder 4 re-enters the inside of the filter cylinder 3, and then deionized water is added, and the cleaning is repeated multiple times.

[0128] Specifically, when the lithium carbonate solid is cleaned of impurity ions, the cam 72 is located in the circular cavity 442, and when the motor 21 drives the stirring shaft 22 to rotate the stirring blade 23, the stirring blade 23 drives the lithium carbonate to rotate in the deionized water for cleaning, and the stirring shaft 22 drives the cam 72 to rotate through the driving shaft 71, so that the driving pipe 44 does not generate a horizontal force.

[0129] When the lithium carbonate solid is filtered or discharged, the threaded pin 8 is unscrewed in sequence, the rotating connecting pin 9 drives the first filter piece 43 to rotate one hundred and eighty degrees and the second filter piece 42 is staggered, then the connecting pin 9 moves down the first filter piece 43 to make the square part 92 of the connecting pin 9 inserted into the square sleeve 412, at this time, the first filter piece 43 moves down, so that the second filter piece 42 moves down, the second filter piece 42 is sleeved on the connecting pin 9 and supported on the first filter piece 43, then the threaded pin 8 is reinstalled to support the second filter piece 42, when the second filter piece 42 moves down, the pipe 44 moves down, the cam 72 enters the oval cavity 441 from the circular cavity 442, then the motor 21 drives the stirring shaft 22 to rotate, the driving shaft 71 drives the cam 72 to rotate, and the cam 72 acts on the two sides of the narrow inner wall of the oval cavity 441, the second filter piece 42 drives the whole cleaning cylinder 4 to reciprocate, and the function of vibrating discharge is realized; at this time, the stirring shaft 22 drives the stirring blade 23 to rotate, which can assist the discharge of lithium carbonate solid particles.

[0130] Therefore, the stirring device 2 can realize the stirring and cleaning of the lithium carbonate solid in one state, and drive the vibration structure 7 to reciprocate the cleaning cylinder 4 in another state, so that the lithium carbonate solid is discharged quickly and uniformly, and the switching of the two states is realized in the process of switching the first filter piece 43 and the second filter piece 42.

[0131] The above is only an embodiment of the present application, and does not limit the patent range of the present application, and any equivalent structure or equivalent process transformation obtained by using the content of the specification and the drawings, or direct or indirect application in other related technical fields, is also included in the patent protection range of the present application.

Claims

1. A production apparatus for the continuous lithium deposition process to prepare battery-grade lithium carbonate, characterized in that, include: A cleaning device, comprising a support, a stirring device, a filter cartridge, a cleaning cartridge, a lifting platform, an installation arm, and a storage tank; The lifting platform is installed on the support, the stirring device is installed on the lifting platform, the lifting platform is used to lift the stirring device, the filter cylinder is installed on the support, one end of the mounting arm is installed on the lifting platform, one end of the cleaning cylinder is located inside the filter cylinder, the other end of the cleaning cylinder is detachably connected to the other end of the mounting arm, and the stirring blade of the stirring device is located inside the cleaning cylinder. The cleaning cartridge includes a cartridge body and a first filter element, the first filter element being detachably installed at the bottom of the cartridge body; The bottom end of the filter cartridge is connected to the storage tank via a valve and a liquid outlet pipe in sequence; The cleaning cartridge also includes a second filter element, which is located between the first filter element and the cartridge body, and the filter pore diameter of the second filter element is larger than the particle size of lithium carbonate; The cleaning device also includes a connecting pin and a threaded pin. A square sleeve and a threaded sleeve are embedded at intervals at the bottom of the cylinder. The threaded pin passes through the first filter element and the second filter element in sequence and is threadedly connected to the threaded sleeve. The connecting pin passes through the square sleeve. A top cap is provided at the top of the connecting pin. A square part is provided on the connecting pin and below the top cap. The square part is the same size as the inner cavity of the square sleeve. The first filter element and the second filter element are both sleeved on the connecting pin and located below the square sleeve. The first filter element is fixedly connected to the connecting pin. The cleaning device also includes a vibration structure. When the cleaning cylinder is removed from the filter cylinder, the vibration structure drives the cleaning cylinder to vibrate reciprocally. The cleaning cylinder can be slidably mounted on the mounting arm. The vibration structure includes a drive shaft and a cam. The bottom end of the stirring shaft in the stirring device is provided with a cylindrical groove. One end of the drive shaft is installed in the cylindrical groove. A drive tube is installed in the center of the second filter element. The top and bottom ends of the drive tube are respectively provided with an elliptical cavity and a circular cavity, and the elliptical cavity and the circular cavity are connected. The other end of the drive shaft passes through the elliptical cavity and extends to the circular cavity and then connects with the cam.

2. A method for producing battery-grade lithium carbonate via continuous lithium deposition, characterized in that, The production apparatus for preparing battery-grade lithium carbonate using continuous lithium deposition as described in claim 1 includes the following steps: S1: Prepare a lithium-containing solution. The lithium-containing solution is obtained by purifying the brine obtained from lithium ore and removing impurities with resin. Then, the lithium-containing solution is put into a container and heated to above 95°C in a water bath for later use. S2: Prepare a carbonate solution. Prepare a carbonate solution of 320~360g / L, and then put the carbonate solution into a container and heat it to above 95℃ in a water bath for later use. S3: Continuous lithium deposition. The microtube jet high-shear mixer is turned on and a certain operating speed is set. The lithium-containing solution and carbonate solution are pumped into the microtube jet high-shear mixer at a certain flow rate using a peristaltic pump to mix and generate lithium carbonate. The particle size is controlled by shearing. The pumping speed of the lithium-containing solution is set, and the pumping speed of the carbonate solution is calculated using the following formula: ； Where v is the flow rate in mL / min, ρ is the mass concentration in g / L, and λ is the excess carbonate coefficient; the lithium carbonate slurry is collected in a beaker and placed in a water bath for stirring and aging for no less than 1 hour. S4: Filter and wash with water. While the lithium carbonate slurry in S3 is still hot, filter to separate the solid and liquid. Then, add the lithium carbonate solid to deionized water according to the preset solid-liquid ratio, wash and stir for 10 minutes, and then filter. Repeat the above water washing 2 to 5 times. Each time, take a small amount of solid sample and dry it in a muffle furnace for 2 hours at a drying temperature of 260℃.

3. The method for producing battery-grade lithium carbonate via continuous lithium deposition according to claim 2, characterized in that, The lithium-containing solution includes one or more of the following: post-resin brine or concentrated brine obtained after three-stage preheating following resin treatment.

4. The method for producing battery-grade lithium carbonate via continuous lithium deposition according to claim 2, characterized in that, The microtube jet high-shear mixer has a shear speed of 900~1800 rpm.

5. The method for producing battery-grade lithium carbonate via continuous lithium deposition according to claim 2, characterized in that, The brine flow rate is 5~100mL / min, and the carbonate flow rate is 1~20mL / min.

6. The method for producing battery-grade lithium carbonate via continuous lithium deposition according to claim 2, characterized in that, The solid in S4 is added to deionized water at a temperature above 95°C at a solid-liquid ratio of 1:3.5 by mass, washed with water and stirred for 10 minutes, and then filtered.

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