Electrochemical lithium extraction device

Abstract

This utility model discloses an electrochemical lithium extraction device, comprising: a lithium removal structure, including an anode current collector and at least two anode liquid distribution frames with anode flow channels, wherein an anode inlet valve and an anode outlet valve are respectively provided at the inlet and outlet ends of the anode flow channels, and the anode current collector is disposed between two adjacent anode liquid distribution frames; a lithium intercalation structure, including a cathode current collector and at least two cathode liquid distribution frames with cathode flow channels, wherein a cathode inlet valve and a cathode outlet valve are provided at the inlet and outlet ends of the cathode flow channels, and the cathode current collector is disposed between two adjacent cathode liquid distribution frames; an ion exchange membrane disposed between the lithium removal structure and the lithium intercalation structure; an anode slurry tank, wherein the outlet end of the anode slurry tank is connected to the anode inlet valve, and the inlet end of the anode slurry tank is connected to the anode outlet valve; and a cathode slurry tank, wherein the outlet end of the cathode slurry tank is connected to the cathode inlet valve, and the inlet end of the cathode slurry tank is connected to the cathode outlet valve. This utility model can solve the problem of slurry deposition and blockage.

Description

Technical Field

[0001] This utility model relates to the field of lithium extraction equipment technology, and in particular to an electrochemical lithium extraction device. Background Technology

[0002] Electrochemical methods can directly and selectively extract and enrich lithium ions from lithium-containing solutions, offering numerous advantages such as cleanliness, high speed, low energy and water consumption, and good selectivity. However, common electrochemical lithium extraction technologies are mostly based on symmetrical fixed electrodes in the FePO4 / LiFePO4 system. This structure suffers from numerous drawbacks, including complex electrode preparation, high cost, susceptibility to polarization, and difficulty in repairing deactivation. To address these shortcomings, some researchers have proposed a symmetrical flow electrode electrochemical adsorption-desorption model. This model involves placing current collectors in two chambers separated by an anion exchange membrane, as illustrated in patent application CN116837229A. Under an applied voltage, the flowing slurry undergoes a redox reaction in the two chambers, achieving rapid extraction and enrichment of lithium ions to overcome the aforementioned deficiencies. However, the slurry in this system has a high viscosity and is unstable, prone to deposition, causing blockage of the flow chamber and hindering long-term circulation. Utility Model Content

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes an electrochemical lithium extraction device.

[0004] The solution to the technical problem of this utility model is:

[0005] An electrochemical lithium extraction device, comprising:

[0006] The delithiation structure includes at least one anode current collector and at least two anode liquid distribution frames. The anode liquid distribution frames are provided with anode flow channels. The inlet end of the anode flow channel is provided with an anode inlet valve, and the outlet end of the anode flow channel is provided with an anode outlet valve. The anode current collector is located between two adjacent anode liquid distribution frames.

[0007] The lithium intercalation structure includes at least one cathode current collector and at least two cathode liquid distribution frames. The cathode liquid distribution frames are provided with cathode flow channels. The inlet end of the cathode flow channel is provided with a cathode inlet valve, and the outlet end of the cathode flow channel is provided with a cathode outlet valve. The cathode current collector is disposed between two adjacent cathode liquid distribution frames.

[0008] An ion exchange membrane is disposed between the delithiation structure and the lithium insertion structure;

[0009] An anode slurry tank, the outlet end of which is connected to each of the anode inlet valves, and the inlet end of which is connected to each of the anode outlet valves;

[0010] A cathode slurry tank, the outlet end of which is connected to each of the cathode inlet valves, and the inlet end of which is connected to each of the cathode outlet valves.

[0011] This invention has at least the following beneficial effects: The anode slurry tank is used to provide anode slurry to the delithiation structure and form a circulation loop for the anode slurry with the delithiation structure; the cathode slurry tank is used to provide cathode slurry to the lithium intercalation structure and form a circulation loop for the cathode slurry with the lithium intercalation structure. The anode slurry achieves delithiation through the delithiation structure, and the cathode slurry achieves lithium intercalation through the lithium intercalation structure, thereby rapidly extracting and enriching lithium ions and improving lithium extraction efficiency. When any anode channel in the delithiation structure becomes blocked, the slurry flow rate of the blocked anode channel can be increased by increasing the opening degree of the anode inlet valve and anode outlet valve, achieving self-cleaning; when any cathode channel in the lithium intercalation structure becomes blocked, the slurry flow rate of the blocked cathode channel can be increased by increasing the opening degree of the cathode inlet valve and cathode outlet valve, achieving self-cleaning, thus effectively solving the problem of slurry deposition.

[0012] As a further improvement to the above technical solution, the electrochemical lithium extraction device further includes:

[0013] The cleaning assembly includes at least four inlet valves, at least four outlet valves, a water storage tank, and a cleaning pump. The outlet end of the water storage tank is connected to the inlet end of the cleaning pump. The inlet valves are respectively located at the inlet end of each of the anode and cathode channels and are respectively connected to the outlet end of the cleaning pump. The outlet valves are respectively located at the outlet end of each of the anode and cathode channels.

[0014] The cleaning components enable online cleaning of the anode and cathode channels. Since each anode and cathode channel is independent of the others, clean water can enter the corresponding channel by opening the inlet and outlet valves of the blocked channel, while other channels remain unaffected and can perform delithiation or lithium insertion normally.

[0015] As a further improvement to the above technical solution, the cleaning assembly also includes a washing water tank and a filter component. The inlet end of the washing water tank is connected to the outlet end of each of the water outlet valves, the outlet end of the washing water tank is connected to the inlet end of the filter component, and the outlet end of the filter component is connected to the inlet end of the water storage tank. This configuration enables the recycling of cleaning water, reduces water waste, and minimizes slurry loss.

[0016] As a further improvement to the above technical solution, the electrochemical lithium extraction device further includes:

[0017] At least four flow meters are provided, each located at the inlet end of one of the anode channels and one of the cathode channels, and are used to obtain the inlet flow rate value of the corresponding anode channel or cathode channel.

[0018] By setting up flow meters, the inlet flow rate of each anode or cathode channel can be obtained, which makes it easier to understand the channel blockage in a timely manner and clean the blocked channels promptly.

[0019] As a further improvement to the above technical solution, each of the anode and cathode channels includes multiple straight channels and multiple arc-shaped channels. The straight channels are parallel to each other, and two adjacent straight channels are connected sequentially through the arc-shaped channels to form a single channel. This arrangement allows the slurry to flow at relatively uniform speeds at various locations in the anode and cathode channels, reducing the possibility of slurry blockage.

[0020] As a further improvement to the above technical solution, the aspect ratio of the anode channel is greater than or equal to 1 and less than or equal to 5; the aspect ratio of the cathode channel is greater than or equal to 1 and less than or equal to 5. This configuration effectively increases the contact area between the electrode slurry and the current collector, resulting in higher charge exchange efficiency, lower system voltage polarization, and better lithium extraction.

[0021] As a further improvement to the above technical solution, the anode flow channel runs through both sides of the anode liquid distribution frame, the cathode flow channel runs through both sides of the cathode liquid distribution frame, the delithiation structure, the lithium insertion structure and the ion exchange membrane together form a lithium extraction component, and the electrochemical lithium extraction device further includes: a clamping plate, the clamping plate is disposed at both ends of the lithium extraction component to cover the anode flow channel and the cathode flow channel located at both ends.

[0022] This design facilitates the processing of the anode and cathode channels, reduces the production cost of the anode and cathode liquid distribution frames, and makes the assembly of the anode, cathode, and clamping plates convenient.

[0023] As a further improvement to the above technical solution, the inlet and outlet ends of each anode flow channel are respectively located at opposite corners of the anode liquid distribution frame; the inlet and outlet ends of each cathode flow channel are respectively located at opposite corners of the cathode liquid distribution frame. This arrangement effectively utilizes the entire anode or cathode liquid distribution frame, increasing the contact area between the slurry and the anode or cathode current collector, and is also more conducive to connecting the inlet and outlet of the anode slurry tank or the cathode slurry tank.

[0024] As a further improvement to the above technical solution, the anode channels located on the left and right sides of the anode current collector are symmetrically arranged with respect to the anode current collector; the cathode channels located on the left and right sides of the cathode current collector are symmetrically arranged with respect to the cathode current collector; and the inlet ends of the anode channels and cathode channels located on the left and right sides of the ion exchange membrane are staggered. This arrangement facilitates assembly.

[0025] As a further improvement to the above technical solution, multiple delithiation structures and multiple lithium insertion structures are provided, and the multiple delithiation structures and multiple lithium insertion structures are arranged alternately. Providing multiple delithiation structures and multiple lithium insertion structures can further improve lithium extraction efficiency. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly explained below. Obviously, the described drawings are only a part of the embodiments of this utility model, and not all of them. Those skilled in the art can obtain other design schemes and drawings based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the overall structure of the electrochemical lithium extraction device according to an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the delithiation structure and the lithium insertion structure of an embodiment of this utility model;

[0029] Figure 3 This is a schematic diagram of the structure of the anode flow channel or cathode flow channel in an embodiment of this utility model.

[0030] Reference numerals: 100, Delithiation structure; 110, Anode liquid distribution frame; 111, Anode inlet valve; 112, Anode outlet valve; 120, Anode current collector; 130, Anode flow channel; 131, Straight channel; 132, Arc-shaped channel; 200, Lithium insertion structure; 210, Cathode liquid distribution frame; 211, Cathode inlet valve; 212, Cathode outlet valve; 220, Cathode current collector; 230, Cathode flow channel; 300, Ion exchange membrane; 400, Anode slurry tank; 410, Anode slurry pump; 500, Cathode slurry tank; 510, Cathode slurry pump; 600, Water storage tank; 610, Inlet valve; 620, Outlet valve; 630, Cleaning pump; 640, Filter component; 650, Washing water tank; 700, Pressure plate. Detailed Implementation

[0031] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0032] In the description of this utility model, the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0033] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0034] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0035] Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are all within the scope of protection of this utility model. The various technical features of this utility model can be combined interactively without contradicting each other.

[0036] Reference Figure 1 and Figure 2 This utility model embodiment proposes an electrochemical lithium extraction device that can achieve rapid extraction and enrichment of lithium ions and solve the problem of slurry deposition and blockage. Moreover, it is simpler to process and assemble and has lower production costs.

[0037] In this embodiment, the electrochemical lithium extraction device includes a delithiation structure 100, a lithium insertion structure 200, an ion exchange membrane 300, an anode slurry tank 400, and a cathode slurry tank 500. The ion exchange membrane 300 is disposed between the delithiation structure 100 and the lithium insertion structure 200. The anode slurry tank 400 supplies anode slurry to the delithiation structure 100 and forms a circulation loop for the anode slurry with the delithiation structure 100. The cathode slurry tank 500 supplies cathode slurry to the lithium insertion structure 200 and forms a circulation loop for the cathode slurry with the lithium insertion structure 200.

[0038] In this embodiment, refer to Figure 2 The delithiation structure 100 includes at least one anode current collector 120 and at least two anode liquid distribution frames 110. The anode liquid distribution frames 110 are arranged along a first direction, and each anode liquid distribution frame 110 is provided with an anode flow channel 130. The anode current collector 120 is disposed between two adjacent anode liquid distribution frames 110, and the anode flow channels 130 on the two adjacent anode liquid distribution frames 110 are isolated from each other through the anode current collector 120. When the anode current collector 120 is energized, the anode slurry flowing in the two adjacent anode flow channels 130 does not interfere with each other. The anode slurry located on both sides of the anode current collector 120 can contact the anode current collector 120 to achieve charge transfer, and lithium ions can be desorbed from the active particles of the anode slurry and enter the solution.

[0039] The lithium intercalation structure 200 includes at least one cathode current collector 220 and at least two cathode liquid distribution frames 210. The cathode liquid distribution frames 210 are arranged along a first direction, and each cathode liquid distribution frame 210 is provided with a cathode flow channel 230. The cathode current collector 220 is disposed between two adjacent cathode liquid distribution frames 210, and the cathode flow channels 230 on the two adjacent cathode liquid distribution frames 210 are isolated from each other through the cathode current collector 220. When the cathode current collector 220 is energized, the cathode slurry flowing in the two adjacent cathode flow channels 230 does not interfere with each other, and the cathode slurry located on both sides of the cathode current collector 220 can contact the cathode current collector 220 to achieve charge transfer, and the free lithium ions in the solution can be intercalated into the active particles.

[0040] For ease of description, the left-right direction is taken as the first direction below, that is, the anode liquid distribution frame 110 is arranged in the left-right direction, and the cathode liquid distribution frame 210 is arranged in the left-right direction.

[0041] Reference Figure 1 , Figure 1The middle arrow indicates the direction of material movement. The outlet end of the anode slurry tank 400 is connected to the inlet end of each anode channel 130, and the inlet end of the anode slurry tank 400 is connected to the outlet end of each anode channel 130. The anode slurry tank 400 can store anode slurry, and its inlet end is equipped with an anode slurry pump 410. Under the action of the anode slurry pump 410, the anode slurry is pumped out into each anode channel 130, where it undergoes delithiation, and then flows back into the anode slurry tank 400 from the outlet end of the anode channel 130. This cycle is repeated multiple times.

[0042] The outlet end of the cathode slurry tank 500 is connected to the inlet end of each cathode channel 230, and the inlet end of the cathode slurry tank 500 is connected to the outlet end of each cathode channel 230. The cathode slurry tank 500 can store cathode slurry, and its inlet end is equipped with a cathode slurry pump 510. Under the action of the cathode slurry pump 510, the cathode slurry is pumped out into each cathode channel 230, where lithium is intercalated, and then flows back into the cathode slurry tank 500 from the outlet end of the cathode channel 230. This cycle is repeated multiple times.

[0043] It is understood that the ion exchange membrane 300 is disposed between the delithiation structure 100 and the lithium insertion structure 200. The left and right sides of the ion exchange membrane 300 are respectively connected to an anode liquid distribution frame 110 at the end of the delithiation structure 100 and a cathode liquid distribution frame 210 at the end of the lithium insertion structure 200. The anode liquid distribution frame 110 at the end of the delithiation structure 100, the cathode liquid distribution frame 210 at the end of the lithium insertion structure 200, and the ion exchange membrane 300 together form an ion exchange chamber. The anode slurry in the anode flow channel 130 of the ion exchange chamber can contact the ion exchange membrane 300, and the cathode slurry in the cathode flow channel 230 of the ion exchange chamber can contact the ion exchange membrane 300, so that the anode slurry and cathode slurry in the ion exchange chamber achieve anion balance through the ion exchange membrane 300.

[0044] Since both the anode and cathode slurries are circulated, the anode slurry undergoes delithiation upon entering each anode channel 130, and the cathode slurry undergoes lithium insertion upon entering each cathode channel 230. Although anion balance cannot be achieved in the other anode channels 130 and cathode channels 230 outside the ion exchange chamber, the delithiated anode slurry and the lithium-inserted cathode slurry can enter the ion exchange chamber during circulation to achieve anion balance. In this embodiment, the ion exchange membrane 300 is an anion exchange membrane 300.

[0045] Understandably, with this setup, the slurry in multiple anode channels 130 can be delithiated simultaneously, and the slurry in multiple cathode channels 230 can be lithium-intercalated simultaneously, thereby improving the efficiency of delithiation of the anode slurry and the efficiency of lithium intercalation of the cathode slurry.

[0046] In this embodiment, each anode channel 130 is equipped with an anode inlet valve 111 at its inlet end, the outlet end of the anode slurry pump 410 is connected to the inlet end of each anode inlet valve 111, and each anode channel 130 is equipped with an anode outlet valve 112 at its outlet end. The inlet end of the anode slurry tank 400 is connected to the outlet end of each anode outlet valve 112. During the operation of the electrochemical lithium extraction device, when slurry deposition occurs in a certain anode channel 130, the operator can temporarily close the anode inlet valves 111 and anode outlet valves 112 of other anode channels 130 to ensure that the slurry in the blocked anode channel 130 has a high flow rate, achieving self-cleaning. Moreover, by adjusting each anode inlet valve 111 and each anode outlet valve 112, the anode slurry can be evenly distributed in each anode channel 130.

[0047] Each cathode flow channel 230 is equipped with a cathode inlet valve 211 at its inlet end. The outlet end of the cathode slurry pump 510 is connected to the inlet end of each cathode inlet valve 211. Each cathode flow channel 230 is equipped with a cathode outlet valve 212 at its outlet end. The inlet end of the cathode slurry tank 500 is connected to the outlet end of each cathode outlet valve 212. During the operation of the electrochemical lithium extraction device, when slurry deposition occurs in a certain cathode flow channel 230, the operator can temporarily close the cathode inlet valves 211 and cathode outlet valves 212 of other cathode flow channels 230 to ensure that the slurry in the blocked cathode flow channel 230 has a large flow rate, achieving self-cleaning. Moreover, by adjusting each cathode inlet valve 211 and each cathode outlet valve 212, the uniform distribution of cathode slurry in each cathode flow channel 230 can be achieved.

[0048] In some embodiments, refer to Figure 1 The electrochemical lithium extraction device also includes a cleaning component, which can clean the anode channel 130 or the cathode channel 230, further preventing slurry blockage in the anode channel 130 and the cathode channel 230, and improving the operational stability of the electrochemical lithium extraction device.

[0049] In this embodiment, the cleaning assembly includes at least four inlet valves 610, at least four outlet valves 620, a water storage tank 600, and a cleaning pump 630. The outlet end of the water storage tank 600 is connected to the inlet end of the cleaning pump 630. The inlet valves 610 are respectively located at the inlet end of each of the anode flow channels 130 and each of the cathode flow channels 230, and are respectively connected to the inlet end of the cleaning pump 630. The outlet valves 620 are respectively located at the outlet end of each of the anode flow channels 130 and each of the cathode flow channels 230.

[0050] When slurry blockage occurs in any anode channel 130 or cathode channel 230, the anode inlet valve 111 and anode outlet valve 112 corresponding to the blocked anode channel 130, or the cathode inlet valve 211 and cathode outlet valve 212 corresponding to the blocked anode channel 130, can be closed. Meanwhile, the inlet valve 610 and outlet valve 620 corresponding to the blocked anode channel 130 or cathode channel 230 can be opened, and the cleaning pump 630 can be started. The cleaning pump 630 can extract cleaning water from the storage tank 600 and allow the cleaning water to flow into the blocked anode channel 130 or cathode channel 230. Since each anode channel 130 or each cathode channel 230 is independently configured, the cleaning water flows and cleans the blocked channel without affecting the slurry circulation in other channels, thus enabling online cleaning.

[0051] In some embodiments, the cleaning assembly further includes a washing water tank 650 and a filter element 640. The inlet end of the washing water tank 650 is connected to the outlet end of each water outlet valve 620, the outlet end of the washing water tank 650 is connected to the inlet end of the filter element 640, and the outlet end of the filter element 640 is connected to the inlet end of the water storage tank 600, enabling the recycling of cleaning water.

[0052] Specifically, the cleaning water in the storage tank 600 is drawn out by the cleaning pump 630, and after passing through the inlet valve 610, the anode flow channel 130 or the cathode flow channel 230 and the outlet valve 620, it returns to the washing water tank 650. The water containing slurry in the washing water tank 650 is filtered by the filter component 640 and then flows back to the storage tank 600, realizing the reuse of clean water, greatly reducing water consumption, and reducing slurry loss.

[0053] In some embodiments, the electrochemical lithium extraction device further includes at least four flow meters, which are respectively located at the inlet end of each anode channel 130 and each cathode channel 230, and are used to obtain the inlet flow value of the corresponding anode channel 130 or cathode channel 230.

[0054] Understandably, since all channel dimensions, slurry density, and conductivity are fixed values, the flow rate in a single anode channel 130 or cathode channel 230 is a fixed value. When a channel becomes blocked, the slurry flow rate in that channel will gradually decrease. Therefore, the presence of blockage in the corresponding channel can be determined based on the inlet flow rate value obtained from the flow meter.

[0055] Because of the flow meter, the operator can control each anode inlet valve 111, anode outlet valve 112, cathode inlet valve 211, cathode outlet valve 212, water inlet valve 610, and water outlet valve 620 manually or by program control based on the inlet flow value obtained by the flow meter. This allows for slurry self-cleaning or cleaning with cleaning water to clean the blocked anode flow channel 130 or cathode flow channel 230, thus resolving the existing flow channel blockage problem.

[0056] In some embodiments, the electrochemical lithium extraction device further includes an alarm component electrically connected to a flow meter, which issues an alarm when the inlet flow rate value obtained by the flow meter is less than or equal to a preset flow rate threshold.

[0057] In some embodiments, the anode inlet valve 111, anode outlet valve 112, cathode inlet valve 211, cathode outlet valve 212, water inlet valve 610, and water outlet valve 620 are all solenoid valves. The electrochemical lithium extraction device also includes a control module. Each solenoid valve and each flow meter are electrically connected to the control module. The inlet flow value obtained by the flow meter is transmitted to the control module. The control module controls the opening or closing of each solenoid valve according to the comparison result between the inlet flow value and the preset flow threshold.

[0058] In some embodiments, refer to 2 and Figure 3 Each anode flow channel 130 and each cathode flow channel 230 includes multiple straight channels 131 and multiple arc channels 132. In the same liquid distribution frame, each straight channel 131 is arranged vertically, and multiple straight channels 131 are arranged in the front-back direction. Adjacent straight channels 131 are connected in sequence through arc channels 132 and together form a single flow channel.

[0059] Understandably, this serpentine single flow channel effectively utilizes the entire anode distribution frame 110 or cathode distribution frame 210, increasing the contact area between the slurry and the anode current collector 120 or cathode current collector 220, resulting in higher charge exchange efficiency, lower system voltage polarization, and better lithium extraction. Furthermore, the slurry has a high viscosity (approximately 2000 Pa·s), making it prone to deposition. If two adjacent straight channels 131 are connected at right angles, the slurry flow velocity at the bends in the flow channel will be uneven, easily leading to deposition and blockage. However, by using an arc-shaped channel 132 to connect the straight channels 131, the flow velocity at each position in the arc-shaped corner is relatively balanced, resulting in lower resistance and reducing slurry blockage in the flow channel.

[0060] In some embodiments, the aspect ratio of the anode channel 130 is greater than or equal to 1 and less than or equal to 5, and the aspect ratio of the cathode channel 230 is greater than or equal to 1 and less than or equal to 5. Channels with aspect ratios within this range can not only reduce the clogging frequency, but also effectively increase the contact area between the electrode slurry and the current collector, resulting in higher charge exchange efficiency, lower system voltage polarization, and better lithium extraction.

[0061] In this embodiment, the anode channel 130 is 30mm wide and 10mm deep; the cathode channel 230 is 30mm wide and 10mm deep.

[0062] In some embodiments, the anode flow channel 130 extends through both sides of the anode liquid distribution frame 110, and the cathode flow channel 230 extends through both sides of the cathode liquid distribution frame 210. That is, both the anode liquid distribution frame 110 and the cathode liquid distribution frame 210 are hollow designs. The delithiation structure 100, the lithium insertion structure 200, and the ion exchange membrane 300 together form a lithium extraction component. The electrochemical lithium extraction device also includes a clamping plate 700, which is disposed at the left and right ends of the lithium extraction component to cover the anode flow channel 130 and the cathode flow channel 230 located at both ends.

[0063] It is understandable that setting the anode flow channel 130 through both sides of the anode liquid distribution frame 110 facilitates the processing of the anode flow channel 130 and reduces costs. Setting the cathode flow channel 230 through both sides of the cathode liquid distribution frame 210 is more conducive to the processing of the cathode flow channel 230 and also reduces costs. The left and right sides of the anode flow channel 130 are isolated by the clamping plate 700 and the anode current collector 120 or two anode current collectors 120, which can prevent slurry leakage and also prevent adjacent anode flow channels 130 from interfering with each other. The left and right sides of the cathode flow channel 230 are isolated by the clamping plate 700 and the cathode current collector 220 or two cathode current collectors 220, which can prevent slurry leakage and also prevent adjacent cathode flow channels 230 from interfering with each other. The assembly of the anode liquid distribution frame 110, the clamping plate 700, the ion exchange membrane 300, the cathode current collector 220, and the anode current collector 120 is also very convenient.

[0064] In some embodiments, the inlet and outlet ends of each anode flow channel 130 are respectively located at opposite corners of the anode liquid distribution frame 110, and the inlet and outlet ends of each cathode flow channel 230 are respectively located at opposite corners of the cathode liquid distribution frame 210. This arrangement effectively utilizes the entire anode liquid distribution frame 110 or cathode liquid distribution frame 210, increasing the contact area between the slurry and the anode current collector 120 or cathode current collector 220, and is also more conducive to connecting the inlet and outlet of the anode slurry tank 400 or the cathode slurry tank 500.

[0065] It is understandable that, since the flow channels on adjacent liquid distribution frames are isolated from each other, the relative positions of the inlet ends and outlet ends of the flow channels on each liquid distribution frame have no significant impact on lithium extraction performance.

[0066] In some embodiments, the anode channels 130 located on the left and right sides of the anode current collector 120 are symmetrically arranged with respect to the anode current collector 120, and the cathode channels 230 located on the left and right sides of the cathode current collector 220 are symmetrically arranged with respect to the cathode current collector 220; the inlet ends of the anode channels 130 and cathode channels 230 located on both sides of the ion exchange membrane 300 are located on the front and rear sides, respectively. This arrangement is particularly convenient for assembly in electrochemical lithium extraction devices with multiple delithiation structures 100 and lithium insertion structures 200.

[0067] In some embodiments, the electrochemical lithium extraction device comprises multiple delithiation structures 100 and lithium insertion structures 200, which are arranged at intervals along the left-right direction, and an ion exchange membrane 300 is disposed between adjacent delithiation structures 100 and lithium insertion structures 200. This arrangement can further improve the lithium extraction efficiency.

[0068] In some embodiments, each delithiation structure 100 may have two or more anode liquid distribution frames 110, with the number of anode liquid distribution frames 110 being one more than the number of anode current collectors 120. However, since the delithiation rate needs to be coordinated with the anion balance rate, setting more anode liquid distribution frames 110 and anode current collectors 120 will reduce the lithium extraction effect. Preferably, each delithiation structure 100 is provided with two or three anode liquid distribution frames 110 to achieve a better lithium extraction effect. The principle of the lithium insertion structure 200 is the same. Each lithium insertion structure 200 may have two or more cathode liquid distribution frames 210, with the number of cathode liquid distribution frames 210 being one more than the number of cathode current collectors 220. To achieve a better lithium insertion effect, preferably, each lithium insertion structure 200 is provided with two or three cathode liquid distribution frames 210.

[0069] During the lithium extraction process using the electrochemical lithium extraction device of this embodiment, when a cathode flow channel 230 or anode flow channel 130 becomes blocked, slurry self-cleaning, cleaning with cleaning water, or alternating between slurry self-cleaning and cleaning with cleaning water can be used to resolve the blockage problem. Taking this embodiment as an example, a single anode current collector 120 and two anode liquid distribution frames 110 are provided in the detached structure, while a single cathode current collector 220 and two cathode liquid distribution frames 210 are provided in the lithium intercalation structure 200.

[0070] In this embodiment, the self-cleaning method is as follows: a fixed program is set so that the cleaning time interval in each cathode channel 230 or each anode channel 130 is the same, that is, a fixed time interval is set for one round of self-cleaning. Preferably, each cathode channel 230 and each anode channel 130 is cleaned once every 3 hours, the cleaning flow rate is 1 m / s, and the cleaning time for a single cleaning is 3 minutes. To prevent the ion exchange membrane 300 from being damaged, the anode channels 130 and cathode channels 230 on both sides of the ion exchange membrane 300 can be cleaned simultaneously. For example, after the electrochemical lithium extraction device has been running for 3 hours, the opening of the cathode inlet valve 211 and cathode outlet valve 212 corresponding to the cathode channel 230 on the left side of the ion exchange membrane 300 is increased, the opening of the anode inlet valve 111 and anode outlet valve 112 corresponding to the anode channel 130 on the right side of the ion exchange membrane 300 is increased, the opening of the other cathode inlet valve 211, cathode outlet valve 212, anode inlet valve 111 and anode outlet valve 112 is decreased, all inlet valves 610 and outlet valves 620 are closed, and the system is restored after rinsing for 3 minutes. This completes the self-cleaning of the anode channel 130 and cathode channel 230 on both sides of the ion exchange membrane 300.

[0071] In this embodiment, the cleaning method is as follows: a fixed program is set so that the time interval between cleaning of each cathode channel 230 and anode channel 130 is the same, that is, a fixed time interval is set for one round of cleaning. Preferably, each anode channel 130 and cathode channel 230 is cleaned once every 5 hours, the cleaning flow rate is 1m / s, and the cleaning time for a single cleaning is 2 minutes. For example, after the electrochemical lithium extraction device has been running for 5 hours, the cathode inlet valve 211 and cathode outlet valve 212 corresponding to the leftmost cathode channel 230 are closed, and the water inlet valve 610 and water outlet valve 620 corresponding to the cathode channel 230 are opened. The cleaning pump 630 is then started to flush the slurry deposited in the cathode channel 230 at a high flow rate of not less than 1 m / s for 2 minutes. After flushing, the cathode inlet valve 211, cathode outlet valve 212, water inlet valve 610, and water outlet valve 620 corresponding to the cathode channel 230 are restored to their initial state. A 5-second time interval is set, and the cathode distribution frame 210 on the right side is immediately cleaned, completing one round of cleaning. The next round of cleaning is performed 5 hours later. The cleaning process for the anode distribution frame 110 is the same.

[0072] In this embodiment, the method of self-cleaning followed by cleaning with cleaning water is as follows: a fixed program is set so that the time interval between cleaning each cathode channel 230 and anode channel 130 is the same, that is, a fixed time interval is set for one round of cleaning. Each cathode channel 230 or anode channel 130 is cleaned once every 8 hours, in two steps. The flow rate of the cleaning slurry and the cleaning water is 1 m / s, and the time is 2 minutes for each step. The time interval between the two cleaning steps is 5 seconds, and the time interval between cleaning each channel is also 5 seconds. For example, after the electrochemical lithium extraction device has been running for 8 hours, the first step of self-cleaning is performed. The cathode inlet valve 211 and cathode outlet valve 212 corresponding to the left cathode channel 230 are increased, while the cathode inlet valve 211 and cathode outlet valve 212 corresponding to other cathode channels 230 are decreased or closed. All inlet valves 610 and outlet valves 620 are closed. The slurry deposited in the left cathode channel 230 is flushed with a large flow rate of not less than 1 m / s. After flushing, each cathode inlet valve 211 and cathode outlet valve 212 is restored to its initial state. After 5 seconds, begin cleaning with cleaning water. Close the cathode inlet valve 211 and cathode outlet valve 212 corresponding to the left cathode channel 230, and open the water inlet valve 610 and water outlet valve 620 corresponding to the left cathode channel 230. Rinse the cathode channel 230 with a high-flow-rate cleaning water of at least 1 m / s for 2 minutes to remove any uncleaned slurry. After rinsing, restore the cathode inlet valve 211, cathode outlet valve 212, water inlet valve 610, and water outlet valve 620 corresponding to the left cathode channel 230 to their initial states. After 5 seconds, perform the same cleaning process on the right cathode channel 230. After one round of cleaning, perform the next round of cleaning after 8 hours. The cleaning process for the anode channel 130 is the same as that for the cathode channel 230.

[0073] In this embodiment, the slurry in each anode distribution frame 110 and cathode distribution frame 210 of the electrochemical lithium extraction device is independent of each other. The slurry flows along the same path in each anode channel 130 and each cathode channel 230, resulting in uniform force and reducing the likelihood of clogging. By controlling each anode inlet valve 111 and each anode outlet valve 112, the slurry distribution in each anode channel 130 is uniform, and any clogged anode channels 130 can be self-cleaned. Similarly, by controlling each cathode inlet valve 211 and each cathode outlet valve 212, the slurry distribution in each cathode channel 230 is uniform, and any clogged cathode channels 230 can be self-cleaned. Furthermore, in this embodiment, the components of the electrochemical lithium extraction device are easy to process and assemble, resulting in low production costs. In addition, due to the cleaning components, by reasonably designing the positions of the inlet valve 610 and the outlet valve 620 and adjusting the opening of each inlet valve 610 and the outlet valve 620, each anode channel 130 or cathode channel 230 can be cleaned with cleaning water, further avoiding channel blockage and ensuring stable system operation.

[0074] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. An electrochemical lithium extraction device, characterized in that, include: The delithiation structure (100) includes at least one anode current collector (120) and at least two anode liquid distribution frames (110). The anode liquid distribution frame (110) is provided with an anode flow channel (130). The inlet end of the anode flow channel (130) is provided with an anode inlet valve (111), and the outlet end of the anode flow channel (130) is provided with an anode outlet valve (112). The anode current collector (120) is located between two adjacent anode liquid distribution frames (110). The lithium intercalation structure (200) includes at least one cathode current collector (220) and at least two cathode liquid distribution frames (210). The cathode liquid distribution frame (210) is provided with a cathode flow channel (230). The inlet end of the cathode flow channel (230) is provided with a cathode inlet valve (211), and the outlet end of the cathode flow channel (230) is provided with a cathode outlet valve (212). The cathode current collector (220) is located between two adjacent cathode liquid distribution frames (210). An ion exchange membrane (300) is disposed between the delithiation structure (100) and the lithium insertion structure (200); An anode slurry tank (400) is provided, with its outlet end connected to each of the anode inlet valves (111) and its inlet end connected to each of the anode outlet valves (112). A cathode slurry tank (500) is provided, the outlet of which is connected to each of the cathode inlet valves (211), and the inlet of which is connected to each of the cathode outlet valves (212).

2. The electrochemical lithium extraction apparatus according to claim 1, characterized in that, The electrochemical lithium extraction device also includes: The cleaning assembly includes at least four inlet valves (610), at least four outlet valves (620), a water storage tank (600), and a cleaning pump (630). The outlet end of the water storage tank (600) is connected to the inlet end of the cleaning pump (630). The inlet valves (610) are respectively located at the inlet end of each anode channel (130) and each cathode channel (230), and are respectively connected to the outlet end of the cleaning pump (630). The outlet valves (620) are respectively located at the outlet end of each anode channel (130) and each cathode channel (230).

3. The electrochemical lithium extraction apparatus according to claim 2, characterized in that, The cleaning assembly also includes a washing tank (650) and a filter element (640). The inlet end of the washing tank (650) is connected to the outlet end of each of the water outlet valves (620), the outlet end of the washing tank (650) is connected to the inlet end of the filter element (640), and the outlet end of the filter element (640) is connected to the inlet end of the water storage tank (600).

4. The electrochemical lithium extraction apparatus according to claim 2, characterized in that, The electrochemical lithium extraction device also includes: At least four flow meters are provided at the inlet end of each of the anode flow channels (130) and each of the cathode flow channels (230), and are used to obtain the inlet flow value of the corresponding anode flow channel (130) or cathode flow channel (230).

5. The electrochemical lithium extraction apparatus according to claim 1, characterized in that, Each of the anode flow channels (130) and each of the cathode flow channels (230) includes multiple straight channels (131) and multiple arc channels (132), respectively. The straight channels (131) are parallel to each other, and two adjacent straight channels (131) are connected in sequence through the arc channels (132) to form a single flow channel.

6. The electrochemical lithium extraction apparatus according to claim 1, characterized in that, The width-to-depth ratio of the anode channel (130) is greater than or equal to 1 and less than or equal to 5; the width-to-depth ratio of the cathode channel (230) is greater than or equal to 1 and less than or equal to 5.

7. The electrochemical lithium extraction apparatus according to claim 1, characterized in that, The anode flow channel (130) extends through both sides of the anode liquid distribution frame (110), and the cathode flow channel (230) extends through both sides of the cathode liquid distribution frame (210). The delithiation structure (100), the lithium insertion structure (200), and the ion exchange membrane (300) together form a lithium extraction component. The electrochemical lithium extraction device further includes: A clamping plate (700) is disposed at both ends of the lithium extraction assembly to cover the anode channel (130) and the cathode channel (230) located at both ends.

8. The electrochemical lithium extraction apparatus according to claim 1, characterized in that, The inlet and outlet ends of each of the anode flow channels (130) are respectively located at the diagonal of the anode liquid distribution frame (110); the inlet and outlet ends of each of the cathode flow channels (230) are respectively located at the diagonal of the cathode liquid distribution frame (210).

9. The electrochemical lithium extraction apparatus according to claim 1, characterized in that, The anode channels (130) located on the left and right sides of the anode current collector (120) are symmetrically arranged with respect to the anode current collector (120); the cathode channels (230) located on the left and right sides of the cathode current collector (220) are symmetrically arranged with respect to the cathode current collector (220); the inlet ends of the anode channels (130) and the cathode channels (230) located on the left and right sides of the ion exchange membrane (300) are staggered.

10. The electrochemical lithium extraction apparatus according to claim 1, characterized in that, The delithiation structure (100) and the lithium insertion structure (200) are provided in multiples, and the multiple delithiation structures (100) and the multiple lithium insertion structures (200) are arranged at intervals.

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