Lithium extraction device

Abstract

The utility model belongs to the technical field of lithium extraction from salt lakes, and discloses a lithium extraction device which comprises a main tank body, a first container, a second container, a first current collector, a second current collector, a lithium-deficient active substance and a lithium-rich active substance, the main tank body comprises a plurality of first tank cavities and a plurality of second tank cavities, the first container is used for containing brine, and the second container is used for containing brine. The first groove cavity is communicated with the first container, the second container is used for containing lithium-rich liquid, the second groove cavity is communicated with the second container, an anionic membrane is connected between the first container and the second container, anions can move between the first container and the second container through the anionic membrane, and the first current collector and the lithium-deficient active substance are both arranged in the first groove cavity. And the second current collector and the lithium-rich active substance are arranged in the second groove cavity. According to the lithium extraction device provided by the utility model, the number of anion membranes is effectively reduced under the structural arrangement of multiple groove cavities, the overall structure of the device is simplified, and the processing and assembling cost is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium extraction from salt lakes, in particular to a lithium extraction device. Background Art

[0002] At present, the lithium resources in salt lakes are abundant. The main technology of extracting lithium from salt lakes is to extract salt and potassium from salt lake brine to form lithium-containing brine, and then remove impurities to obtain lithium carbonate. Electrochemical adsorption is an emerging salt lake lithium extraction method with simple process, high adsorption capacity, low water consumption and green environmental protection, and is being gradually applied to actual production.

[0003] In the prior art, lithium extraction devices are generally provided with a tank body, with multiple slots spaced apart in the tank body, and multiple slots are arranged in pairs, and an anion membrane is arranged between the two slots in each group. However, the number of anion membranes in the above structure is large, the overall structure is complex, and the cost of processing and assembly is high. Utility Model Content

[0004] The utility model aims to provide a lithium extraction device, which can effectively reduce the number of anion membranes, simplify the overall structure of the device, and effectively reduce processing and assembly costs.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A lithium extraction device, comprising:

[0007] A main tank body, the main tank body comprising a plurality of first tank cavities and a plurality of second tank cavities, wherein the first tank cavities and the second tank cavities are arranged in a one-to-one correspondence;

[0008] A first container, used for containing brine, wherein the first tank cavity is connected to the first container;

[0009] A second container, used for containing lithium-rich liquid, wherein the second tank cavity is connected to the second container;

[0010] an anion membrane, wherein the first container and the second container are connected with the anion membrane, and anions can move between the first container and the second container through the anion membrane;

[0011] A first current collector is disposed in the first slot cavity;

[0012] A lithium-deficient active material is disposed in the first tank cavity;

[0013] A second current collector is disposed in the second slot cavity;

[0014] The lithium-rich active material is disposed in the second tank cavity.

[0015] Optionally, the first groove cavity is provided with a first liquid inlet hole and a first liquid outlet hole, and the second groove cavity is provided with a second liquid inlet hole and a second liquid outlet hole; wherein,

[0016] The first liquid inlet is connected to the first container through a first liquid inlet pipe, and the first liquid outlet is connected to the first container through a first liquid outlet pipe; the second liquid inlet is connected to the second container through a second liquid inlet pipe, and the second liquid outlet is connected to the second container through a second liquid outlet pipe.

[0017] Optionally, the second container is connected to a third liquid inlet pipe communicating therewith, and the first liquid inlet hole can be selectively communicated with any one of the first liquid inlet pipe and the third liquid inlet pipe through a first valve;

[0018] The first container is connected to a third liquid outlet pipe communicating therewith, and the first liquid outlet hole can be selectively communicated with any one of the first liquid outlet pipe and the third liquid outlet pipe through a second valve;

[0019] The first container is connected to a fourth liquid inlet pipe communicating therewith, and the second liquid inlet hole can be selectively communicated with either the second liquid inlet pipe or the fourth liquid inlet pipe through a third valve;

[0020] The second container is connected to a fourth liquid outlet pipe communicating therewith, and the second liquid outlet hole can be selectively communicated with either the second liquid outlet pipe or the fourth liquid outlet pipe through a fourth valve.

[0021] Optionally, a frame is placed in the first tank cavity, and the first current collector and the lithium-deficient active material are placed in the frame; and / or,

[0022] A basket is placed in the second tank cavity, and the second current collector and the lithium-rich active material are placed in the basket;

[0023] The housing has a via hole, and the inner cavity of the housing is connected to the groove cavity where the housing is located through the via hole. The aperture of the via hole is smaller than the particle diameter of the lithium-deficient active material and smaller than the particle diameter of the lithium-rich active material.

[0024] Optionally, the basket body comprises two sub-basket parts, the two sub-basket parts are connected to form a basket inner cavity with an opening at the top, and a side wall of any sub-basket part facing the corresponding current collector is provided with a plurality of the via holes;

[0025] The first current collector divides the corresponding inner cavity of the basket into two first compartments, and lithium-deficient active materials are provided in any of the first compartments; and / or the second current collector divides the corresponding inner cavity of the basket into two second compartments, and lithium-rich active materials are provided in any of the second compartments.

[0026] Optionally, the first liquid inlet, the first liquid outlet, the second liquid inlet and the second liquid outlet are all provided with a filter, and the mesh diameter of the filter is smaller than the particle diameter of the lithium-deficient active material and smaller than the particle diameter of the lithium-rich active material.

[0027] Optionally, two opposite side edges of the first liquid inlet hole extend to two opposite sides of the first current collector respectively, and two opposite sides of the first liquid outlet hole extend to two opposite sides of the first current collector;

[0028] And / or, two opposite side edges of the second liquid inlet hole extend to two opposite sides of the second current collector respectively, and two opposite side edges of the second liquid outlet hole extend to two opposite sides of the second current collector respectively.

[0029] Optionally, the first container is provided with a first hole, the first hole has a first opening end surface facing the second container, and a first sealing gasket is provided between the first opening end surface and the anion membrane.

[0030] And / or, the second container is provided with a second hole, the second hole has a second opening end surface facing the first container, and a second sealing gasket is provided between the second opening end surface and the anion membrane.

[0031] Optionally, the main tank body has a main tank cavity, and a plurality of partitions are arranged in the main tank cavity, and the partitions divide the main tank cavity into a plurality of the first tank cavities and a plurality of the second tank cavities.

[0032] Optionally, the main tank body and the partition are integrally formed.

[0033] Beneficial effects:

[0034] The utility model provides a lithium extraction device, the main tank body includes a plurality of first tank cavities and second tank cavities arranged one by one, the first tank cavity is provided with a first current collector, the first current collector is provided with a lithium-deficient active material, the second tank cavity is provided with a second current collector, the second current collector is provided with a lithium-rich active material. The first current collector and the second current collector are electrically connected through a power supply. Electrons are conducted from the negative electrode of the power supply through a wire to the first current collector, and then through the first current collector to the lithium-deficient active material. The chemical reaction occurring at the lithium-deficient active material is: FePO4+Li + +e - →LiFePO4. The electrons are conducted from the lithium-rich active material to the second current collector, and then to the positive electrode of the power supply through the second current collector and the wire. The chemical reaction occurring at the lithium-rich active material is: LiFePO4→FePO4+Li + +e -To ensure the balance of anions and cations in the first and second chambers and form a closed loop, the Cl - The anion is transferred to the first container by the first slot cavity, then moves to the anion membrane and crosses the membrane, and the anion migrates into the second container, and then is transferred to the second slot cavity by the second container. The above structure does not arrange the anion membrane between the first slot cavity and the second slot cavity as in the prior art, but arranges the anion membrane between the first container and the second container. It is only necessary to arrange the anion membrane between the first container and the second container, and it is not necessary to arrange the anion membrane between the first slot cavity and the second slot cavity of each group, which effectively reduces the number of anion membranes to be arranged, simplifies the overall structure of the device, and effectively reduces the cost of processing and assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural schematic diagram of a lithium extraction device provided in an embodiment of the utility model;

[0036] Figure 2 It is a partial structural schematic diagram of a lithium extraction device provided in an embodiment of the utility model;

[0037] Figure 3 It is a partial structural schematic diagram of a lithium extraction device provided in an embodiment of the utility model;

[0038] Figure 4 It is a structural schematic diagram of a basket and a first current collector provided in an embodiment of the utility model;

[0039] Figure 5 It is a structural schematic diagram of a main tank body provided in an embodiment of the utility model, in which a basket body is arranged;

[0040] Figure 6 It is a structural schematic diagram of a main tank body provided by an embodiment of the utility model with a filter screen arranged therein.

[0041] In the figure:

[0042] 1. Main tank body; 11. First tank cavity; 111. First liquid inlet hole; 112. First liquid outlet hole; 12. Second tank cavity; 121. Second liquid inlet hole; 122. Second liquid outlet hole; 13. Partition plate;

[0043] 21. a first container; 22. a second container;

[0044] 3. Anion membrane;

[0045] 41. a first current collector; 42. a second current collector;

[0046] 51, first liquid inlet pipe; 52, first liquid outlet pipe; 53, second liquid inlet pipe; 54, second liquid outlet pipe; 55, third liquid inlet pipe; 56, third liquid outlet pipe; 57, fourth liquid inlet pipe; 58, fourth liquid outlet pipe;

[0047] 61, first valve; 62, second valve; 63, third valve; 64, fourth valve.

[0048] 7. Basket; 71. Basket section; 711. Via hole;

[0049] 8. Filter;

[0050] 91. First sealing gasket; 92. Second sealing gasket. DETAILED DESCRIPTION

[0051] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0052] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0054] In the description of this embodiment, the terms "upper", "lower", "right", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0055] The embodiment of the utility model provides a lithium extraction device. Figure 1 As shown, the lithium extraction device includes a main tank body 1, a first container 21, a second container 22, a first current collector 41 and a second current collector 42. The main tank body 1 includes a plurality of first tank cavities 11 and second tank cavities 12 arranged in a one-to-one correspondence, the first container 21 is used to accommodate brine, the first tank cavity 11 is connected to the first container 21, the second container 22 is used to accommodate lithium-rich liquid, the second tank cavity 12 is connected to the second container 22, an anion membrane 3 is connected between the first container 21 and the second container 22, the anions in the first container 21 can pass through the anion membrane 3 to reach the second container 22, the first current collector 41 is arranged in the first tank cavity 11, the first tank cavity 11 is provided with a lithium-deficient active material, the second current collector 42 is arranged in the second tank cavity 12, and the second tank cavity 12 is provided with a lithium-rich active material. The first current collector 41 is electrically connected to the negative electrode of the power supply, and the second current collector 42 is electrically connected to the positive electrode of the power supply.

[0056] The lithium-rich active material and the lithium-deficient active material can be lithium-rich lithium iron phosphate and lithium-deficient lithium iron phosphate, respectively. In some other optional ways, the active material can also be set to other materials such as lithium manganese oxide and lithium titanate, which are not limited here.

[0057] It should be noted that the brine is specifically raw brine from salt lakes, which is rich in lithium, sodium, potassium, calcium, magnesium and other ions.

[0058] The lithium-rich solution is specifically a solution rich in lithium ions formed by removing lithium from the saturated active material into a low-concentration salt solution (salt concentration 0.4 g / L).

[0059] The lithium-deficient active material is a substance such as lithium iron phosphate, lithium manganate or lithium titanate containing a large number of lithium vacancies. Among them, the lithium vacancies are 50%-90%. The lithium-rich active material is a substance such as lithium iron phosphate, lithium manganate or lithium titanate that is rich in lithium after adsorption saturation, and the lithium vacancies are 10%-50%. Among them, taking pure lithium iron phosphate as an example, its lithium content is 100%, and the lithium vacancy is recorded as 0%.

[0060] Electrons are conducted from the negative electrode of the power source through the wire to the first current collector 41, and then through the first current collector 41 to the lithium-deficient active material. The chemical reaction occurring at the lithium-deficient active material is: FePO4+Li+ +e - →LiFePO4. The electrons are conducted from the lithium-rich active material to the second current collector 42, and then to the positive electrode of the power supply through the second current collector 42 and the wire. The chemical reaction occurring at the lithium-rich active material is: LiFePO4→FePO4+Li + +e - In order to ensure the balance of anions and cations in the first cavity 11 and the second cavity 12 and form a closed loop, anions such as Cl- in the brine in the first cavity 11 are transferred from the first cavity 11 to the first container 21, then move to the anion membrane 3 and cross the membrane, and the anions migrate to the second container 22, and then are transferred from the second container 22 to the second cavity 12.

[0061] The above structure does not set an anion membrane between the first tank cavity 11 and the second tank cavity 12 as in the prior art, but sets the anion membrane 3 between the first container 21 and the second container 22. It is only necessary to set the anion membrane 3 between the first container 21 and the second container 22, and there is no need to respectively arrange anion membranes between the first tank cavity 11 and the second tank cavity 12 of each group, which effectively reduces the number of anion membranes 3, simplifies the overall structure of the device, and effectively reduces the cost of processing and assembly.

[0062] In certain embodiments, the material of the anion membrane 3 is set to polystyrene-dimethylformamide copolymer or polyacrylic acid or polystyrene sulfate. Exemplarily, polystyrene-dimethylformamide copolymer has higher chemical stability and good mechanical properties, and also has higher ion transfer rate and selectivity. Polyacrylic acid has higher acidity, and also has good gel properties. This makes it can be used as a crosslinking agent in the preparation process of the electrochemical membrane, thereby increasing its thickness and chemical stability. Polystyrene sulfate has excellent ion exchange capacity and higher chemical stability, and also has good mechanical strength and hydrophobic properties.

[0063] In some embodiments, continue to refer to Figure 1 As shown, the main tank body 1 has a main tank cavity, and a plurality of partitions 13 are arranged in the main tank cavity, and the partitions 13 divide the main tank cavity into a plurality of first tank cavities 11 and a plurality of second tank cavities 12. Specifically, the arrangement of the plurality of partitions 13 can divide a complete main tank cavity into a plurality of first tank cavities 11 and second tank cavities 12 corresponding to each other.

[0064] In some embodiments, the main tank body 1 and the partition 13 are integrally formed. Since the combination of the main tank body 1 and the partition 13 has a relatively simple structure, they can be directly integrally formed, which is convenient to process and efficient to form, and avoids the extra time spent on the separate assembly of multiple parts.

[0065] In some embodiments, a second slot cavity 12 is provided between any two adjacent first slot cavities 11, and a first slot cavity 11 is provided between any two adjacent second slot cavities 12. Such an arrangement makes the distribution pattern between the first slot cavities 11 and the second slot cavities 12 orderly, so that each group of correspondingly arranged first slot cavities 11 and second slot cavities 12 can be grouped one by one, and can be placed in order when the current collector is placed later, which is also conducive to orderly wiring when connecting the power supply and the wires to avoid cluttered wires.

[0066] In some embodiments, the first container 21 is provided with a first hole, the second container 22 is provided with a second hole, the first hole has a first open end surface facing the second container 22, the second hole has a second open end surface facing the first container 21, and the anion membrane 3 is sandwiched between the first open end surface and the second open end surface (the first hole and the second hole are not shown in the figure). Specifically, the anion membrane 3 is sandwiched between the first container 21 and the second container 22, one end of the anion membrane 3 is close to the first open end surface of the first hole, and the other end is close to the second open end surface of the second hole, so as to block cations and prevent the solution in the first container 21 and the second container 22 from leaking, and only allow anions to move between the first container 21 and the second container 22 through the anion membrane 3.

[0067] In some embodiments, a first sealing gasket 91 is provided between the first opening end face and the anion membrane 3, and a second sealing gasket 92 is provided between the second opening end face and the anion membrane 3. Specifically, the first sealing gasket 91 is provided between the peripheral edge of the anion membrane 3 and the first opening end face, and can effectively ensure the sealing between the first opening end face and the anion membrane 3. The second sealing gasket 92 is provided between the peripheral edge of the anion membrane 3 and the second opening end face, and can effectively ensure the sealing between the second opening end face and the anion membrane 3. The provision of the first sealing gasket 91 and the second sealing gasket 92 can effectively avoid leakage problems between the anion membrane 3 and the first hole and between the anion membrane 3 and the second hole.

[0068] Exemplarily, the first sealing gasket 91 and the second sealing gasket 92 are both rubber sealing gaskets.

[0069] In some embodiments, reference Figure 2 As shown, the first groove cavity 11 is provided with a first liquid inlet hole 111 and a first liquid outlet hole 112, and the second groove cavity 12 is provided with a second liquid inlet hole 121 and a second liquid outlet hole 122. The first liquid inlet hole 111 is connected to the first container 21 through the first liquid inlet pipe 51, and the first liquid outlet hole 112 is connected to the first container 21 through the first liquid outlet pipe 52; the second liquid inlet hole 121 is connected to the second container 22 through the second liquid inlet pipe 53, and the second liquid outlet hole 122 is connected to the second container 22 through the second liquid outlet pipe 54.

[0070] The brine in the first container 21 is transported through the first liquid inlet pipe 51 and enters the first tank cavity 11 through the first liquid inlet hole 111, and is then transported back to the first container 21 through the first liquid outlet hole 112 and the first liquid outlet pipe 52 in sequence, forming a circulation loop for the flow of brine; the lithium-rich liquid in the second container 22 is transported through the second liquid inlet pipe 53 and enters the second tank cavity 12 through the second liquid inlet hole 121, and is then transported back to the second container 22 through the second liquid outlet hole 122 and the second liquid outlet pipe 54 in sequence, forming a circulation loop for the flow of lithium-rich liquid.

[0071] In some other embodiments, referring to Figure 3 As shown, the second container 22 is connected to a third liquid inlet pipe 55 connected thereto, and the first liquid inlet hole 111 can be selectively connected to either the first liquid inlet pipe 51 or the third liquid inlet pipe 55 through a first valve 61; the first container 21 is connected to a third liquid outlet pipe 56 connected thereto, and the first liquid outlet hole 112 can be selectively connected to either the first liquid outlet pipe 52 or the third liquid outlet pipe 56 through a second valve 62; the first container 21 is connected to a fourth liquid inlet pipe 57 connected thereto, and the second liquid inlet hole 121 can be selectively connected to either the second liquid inlet pipe 53 or the fourth liquid inlet pipe 57 through a third valve 63; the second container 22 is connected to a fourth liquid outlet pipe 58 connected thereto, and the second liquid outlet hole 122 can be selectively connected to either the second liquid outlet pipe 54 or the fourth liquid outlet pipe 58 through a fourth valve 64.

[0072] By controlling the first valve 61, the first liquid inlet pipe 51 or the third liquid inlet pipe 55 is selectively controlled to open, so that the first liquid inlet hole 111 can be selectively connected to the first container 21 or the second container 22. By setting the second valve 62, the first liquid outlet pipe 52 or the third liquid outlet pipe 56 is selectively controlled to open, so that the first liquid outlet hole 112 can be selectively connected to the first container 21 or the second container 22. Exemplarily, the first valve 61 and the second valve 62 open the first liquid inlet pipe 51 and the first liquid outlet pipe 52 respectively, so that the brine in the first container 21 can return to the first container 21 along the first liquid inlet pipe 51, the first liquid inlet hole 111, the first tank cavity 11, the first liquid outlet hole 112, and the first liquid outlet pipe 52, forming a brine flow circulation loop. The first valve 61 and the second valve 62 open the third liquid inlet pipe 55 and the third liquid outlet pipe 56 respectively, so that the lithium-rich liquid in the second container 22 can return to the second container 22 along the third liquid inlet pipe 55, the first liquid inlet hole 111, the first tank cavity 11, the first liquid outlet hole 112, and the third liquid outlet pipe 56, forming a brine flow circulation loop.

[0073] By controlling the third valve 63, the second liquid inlet pipe 53 or the fourth liquid inlet pipe 57 is selectively controlled to open, so that the second liquid inlet hole 121 can be selectively connected to the second container 22 or the first container 21. By setting the fourth valve 64, the second liquid outlet pipe 54 or the fourth liquid outlet pipe 58 is selectively controlled to open, so that the second liquid outlet hole 122 can be selectively connected to the second container 22 or the first container 21. Exemplarily, the third valve 63 and the fourth valve 64 open the second liquid inlet pipe 53 and the second liquid outlet pipe 54 respectively, so that the lithium-rich liquid in the second container 22 can return to the second container 22 along the second liquid inlet pipe 53, the second liquid inlet hole 121, the second tank cavity 12, the second liquid outlet hole 122, and the second liquid outlet pipe 54, forming a lithium-rich liquid flow circulation loop. The third valve 63 and the fourth valve 64 open the fourth liquid inlet pipe 57 and the fourth liquid outlet pipe 58 respectively, so that the brine in the first container 21 can return to the first container 21 along the fourth liquid inlet pipe 57, the second liquid inlet hole 121, the second tank cavity 12, the second liquid outlet hole 122, and the fourth liquid outlet pipe 58, forming a brine flow circulation loop.

[0074] It should be noted that the first valve 61, the second valve 62, the third valve 63 and the fourth valve 64 can all be configured as three-way valves. Specifically, the three valve ports of the first valve 61 are respectively connected to the first liquid inlet hole 111, the first liquid inlet pipe 51 and the third liquid inlet pipe 55, the three valve ports of the second valve 62 are respectively connected to the first liquid outlet hole 112, the first liquid outlet pipe 52 and the third liquid outlet pipe 56, the three valve ports of the third valve 63 are respectively connected to the second liquid inlet hole 121, the second liquid inlet pipe 53 and the fourth liquid inlet pipe 57, and the three valve ports of the fourth valve 64 are respectively connected to the second liquid outlet hole 122, the second liquid outlet pipe 54 and the fourth liquid outlet pipe 58.

[0075] The first valve 61, the second valve 62, the third valve 63 and the fourth valve 64 can also be configured as switch valves. Specifically, the two ends of the first liquid inlet pipe 51 are connected to the first liquid inlet hole 111 and the first container 21, respectively, and the two ends of the third liquid inlet pipe 55 are connected to the first liquid inlet hole 111 and the second container 22, respectively. There are two first valves 61, and the two first valves 61 are respectively arranged on the first liquid inlet pipe 51 and the third liquid inlet pipe 55. The two ends of the first liquid outlet pipe 52 are respectively connected to the first liquid outlet hole 112 and the first container 21, and the two ends of the third liquid outlet pipe 56 are respectively connected to the first liquid outlet hole 112 and the second container 22. There are two second valves 62, and the two second valves 62 are respectively arranged on the first liquid outlet pipe 52 and the third liquid outlet pipe 56. The two ends of the second liquid inlet pipe 53 are respectively connected to the second liquid inlet hole 121 and the second container 22, and the two ends of the fourth liquid inlet pipe 57 are respectively connected to the second liquid inlet hole 121 and the first container 21. Two third valves 63 are provided, and the two third valves 63 are respectively provided on the second liquid inlet pipe 53 and the fourth liquid inlet pipe 57. The two ends of the second liquid outlet pipe 54 are respectively connected to the second liquid outlet hole 122 and the second container 22, and the two ends of the fourth liquid outlet pipe 58 are respectively connected to the second liquid outlet hole 122 and the first container 21. Two fourth valves are provided, and the two fourth valves 64 are respectively provided on the second liquid outlet pipe 54 and the fourth liquid outlet pipe 58.

[0076] In some embodiments, reference Figures 4 to 5 As shown, a basket 7 is placed in the first cavity 11, and the first current collector 41 and the lithium-deficient active material are placed in the basket 7; a basket 7 is placed in the second cavity 12, and the second current collector 42 and the lithium-rich active material are placed in the basket 7. In this arrangement, the current collector and the active material can be taken in and out by taking and putting in the basket 7, and the taking and putting operation of the current collector and the active material is convenient and quick.

[0077] A via 711 is provided on the basket 7, and the inner cavity of the basket 7 is connected with the groove cavity where the basket 7 is located through the via 711, so that the brine and the lithium-rich liquid can effectively flow into the corresponding basket 7 for reaction. The aperture of the via 711 is smaller than the particle diameter of the lithium-deficient active material and smaller than the particle diameter of the lithium-rich active material. It can also prevent the lithium-deficient active material and the lithium-rich active material from flowing out of the basket 7 through the via 711 with the circulating liquid flow, so that the active material always flows around the corresponding current collector, thereby improving the utilization rate of the current collector.

[0078] In some embodiments, the basket 7 includes two sub-basket parts 71, and the two sub-basket parts 71 are connected to form a basket cavity with an opening at the top. The side wall of any sub-basket part 71 facing the corresponding current collector is provided with a plurality of vias 711 connected to the basket cavity; the first current collector 41 divides the corresponding basket cavity into two first compartments, and any first compartment is provided with a lithium-deficient active material; and / or, the second current collector 42 divides the corresponding basket cavity into two second compartments, and any second compartment is provided with a lithium-rich active material. The basket cavity formed by the two sub-basket parts 71 is used for reliable installation of the current collector. The first compartment formed between the first current collector 41 and the basket cavity is used to fully place the lithium-deficient active material, and the second compartment formed between the second current collector 42 and the basket cavity is used to fully place the lithium-rich active material. Specifically, the opposite side edges of the first liquid inlet 111 are respectively located on the opposite sides of the first current collector 41. The brine in the first container 21 can be transported to the first tank cavity 11 through the first liquid inlet 111. The opposite side edges of the first liquid inlet 111 are respectively located on the opposite sides of the first current collector 41, so that the lithium-deficient active materials on the opposite sides of the first current collector 41 can fully react with the solution.

[0079] The opposite side edges of the second liquid inlet hole 121 are respectively located on the opposite sides of the second current collector 42. The lithium-rich liquid in the second container 22 can be transported to the second tank cavity 12 through the second liquid inlet hole 121, and the opposite side edges of the second liquid inlet hole 121 are respectively located on the opposite sides of the second current collector 42, so that the lithium-rich active materials on the opposite sides of the second current collector 42 can fully react with the solution.

[0080] In some embodiments, two sub-basket parts 71 of the same housing 7 are connected by fasteners such as screws, and the current collector is sandwiched between the two corresponding sub-basket parts 71. With this arrangement, the sub-basket parts 71 and the current collector are simply fixed and quickly assembled and disassembled.

[0081] In some other embodiments, referring to Figure 6As shown, the first liquid inlet 111, the first liquid outlet 112, the second liquid inlet 121 and the second liquid outlet 122 are all provided with a filter 8, and the mesh diameter of the filter 8 is smaller than the particle diameter of the lithium-deficient active material and smaller than the particle diameter of the lithium-rich active material. By providing the filter 8, the above-mentioned frame 7 can be omitted under the premise that the first current collector 41 and the second current collector 42 can be effectively fixed. The mesh diameter of the filter 8 provided in the first liquid inlet 111 and the first liquid outlet 112 is smaller than the particle pore size of the lithium-deficient active material, which can ensure that the particles of the lithium-deficient active material are strictly kept in the first groove cavity 11 and will not enter the first container 21; the mesh diameter of the filter 8 provided in the second liquid inlet 121 and the second liquid outlet 122 is smaller than the particle pore size of the lithium-rich active material, which can ensure that the particles of the lithium-rich active material are strictly kept in the second groove cavity 12 and will not enter the second container 22.

[0082] In some embodiments, the first liquid inlet 111 is provided on the bottom wall of the first groove cavity 11 and is located on the side of the first groove cavity 11 away from the first container 21. The second liquid inlet 121 is provided on the bottom wall of the second groove cavity 12 and is located on the side of the second groove cavity 12 away from the second container 22. In other embodiments, the first liquid inlet 111 can also be provided on the groove side wall of the first groove cavity 11, and the second liquid inlet 121 can be provided on the groove side wall of the second groove cavity 12. The first liquid outlet 112 is provided on the bottom wall of the first groove cavity 11 and is located on the side of the first groove cavity 11 close to the first container 21. The second liquid outlet 122 is provided on the bottom wall of the second groove cavity 12 and is located on the side of the second groove cavity 12 close to the second container 22. In other embodiments, the first liquid outlet 112 can also be provided on the groove side wall of the first groove cavity 11, and the second liquid outlet 122 can be provided on the groove side wall of the second groove cavity 12.

[0083] Exemplarily, the use process of the lithium extraction device provided in this embodiment is described below:

[0084] After the first current collector 41 embedded with the lithium-deficient active material is placed in the frame 7, it is fixed together with the frame 7 in the first slot 11. After the second current collector 42 embedded with the lithium-rich active material is placed in the frame 7, it is fixed together with the frame 7 in the second slot 12. The lithium-rich active material and the lithium-deficient active material can be selected as lithium-rich lithium iron phosphate and lithium-deficient lithium iron phosphate, respectively.

[0085] First, connect the negative pole of the power supply to the first current collector 41, and the positive pole of the power supply to the second current collector 42. The first valve 61 and the second valve 62 open the first liquid inlet pipe 51 and the first liquid outlet pipe 52 respectively, so that the brine in the first container 21 can return to the first container 21 along the first liquid inlet pipe 51, the first liquid inlet hole 111, the first tank cavity 11, the first liquid outlet hole 112, and the first liquid outlet pipe 52, forming a brine flow circulation loop; the third valve 63 and the fourth valve 64 open the second liquid inlet pipe 53 and the second liquid outlet pipe 54 respectively, so that the lithium-rich liquid in the second container 22 can return to the second container 22 along the second liquid inlet pipe 53, the second liquid inlet hole 121, the second tank cavity 12, the second liquid outlet hole 122, and the second liquid outlet pipe 54, forming a lithium-rich liquid flow circulation loop. Electrons are conducted from the negative pole of the power supply through the wire to the first current collector 41, and then reach the lithium-deficient lithium iron phosphate through the first current collector 41 and a chemical reaction occurs: FePO4+Li + +e-→LiFePO4. At the same time, the lithium-rich lithium iron phosphate undergoes a chemical reaction: LiFePO4→FePO4+Li + +e - , the electrons are then conducted to the second current collector 42, and finally reach the positive electrode of the power supply along the wire. In order to ensure the balance of anions and cations in the first cell cavity 11 and the second cell cavity 12, and to form a closed loop, the anions such as Cl- in the brine in the first cell cavity 11 are transferred from the first cell cavity 11 to the first container 21, and then move to the anion membrane 3 and cross the membrane, and the anions migrate to the second container 22, and then are transferred from the second container 22 to the second cell cavity 12. After multiple cycles, the lithium-deficient lithium iron phosphate in the first cell cavity 11 becomes lithium-rich lithium iron phosphate, and the lithium-rich lithium iron phosphate in the second cell cavity 12 becomes lithium-deficient lithium iron phosphate.

[0086] Then, replace the new brine in the first container 21, replace the new lithium-rich liquid in the second container 22, and then switch the positive and negative poles of the power supply, connect the positive pole of the power supply to the first current collector 41, and connect the negative pole of the power supply to the second current collector 42. The first valve 61 and the second valve 62 open the third liquid inlet pipe 55 and the third liquid outlet pipe 56 respectively, so that the lithium-rich liquid in the second container 22 can return to the second container 22 along the third liquid inlet pipe 55, the first liquid inlet hole 111, the first tank cavity 11, the first liquid outlet hole 112, and the third liquid outlet pipe 56, forming a lithium-rich liquid flow circulation loop; the third valve 63 and the fourth valve 64 open the fourth liquid inlet pipe 57 and the fourth liquid outlet pipe 58 respectively, so that the brine in the first container 21 can return to the first container 21 along the fourth liquid inlet pipe 57, the second liquid inlet hole 121, the second tank cavity 12, the second liquid outlet hole 122, and the fourth liquid outlet pipe 58, forming a brine flow circulation loop. At this time, a chemical reaction occurs on one side of the first current collector 41: LiFePO4→FePO4+Li + +e -, the lithium ions cannot cross the anion membrane 3 and will all enter the lithium-rich solution in the second container 22, thereby realizing the lithium extraction process.

[0087] It is worth mentioning that when the lithium concentration of the brine solution in the first container 21 is less than 0.1 g / L, a new brine solution needs to be replaced in the first container 21. When the lithium concentration of the lithium-rich solution in the second container 22 is higher than 1.5 g / L, a new lithium-rich solution needs to be replaced in the second container 22.

[0088] In summary, the lithium extraction device provided in this embodiment has a simple structure. It is only necessary to set an anion membrane 3 between the first container 21 and the second container 22. There is no need to respectively arrange anion membranes 3 between the first slot cavity 11 and the second slot cavity 12 of each group, which effectively reduces the number of anion membranes 3 arranged, simplifies the overall structure of the device, and effectively reduces the cost of processing and assembly.

[0089] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A lithium extraction device, characterized in that: include: A main tank body (1), the main tank body (1) comprising a plurality of first tank cavities (11) and a plurality of second tank cavities (12), the first tank cavities (11) and the second tank cavities (12) being arranged in a one-to-one correspondence; A first container (21) for containing brine, wherein the first tank cavity (11) is connected to the first container (21); A second container (22) for containing lithium-rich liquid, wherein the second tank cavity (12) is connected to the second container (22); an anion membrane (3), wherein the anion membrane (3) is connected between the first container (21) and the second container (22), and anions can move between the first container (21) and the second container (22) through the anion membrane (3); A first current collector (41) is disposed in the first slot cavity (11); The lithium-deficient active material is disposed in the first groove cavity (11); A second current collector (42) is disposed in the second slot cavity (12); The lithium-rich active material is arranged in the second tank cavity (12).

2. The lithium extraction device according to claim 1, characterized in that: The first groove cavity (11) is provided with a first liquid inlet hole (111) and a first liquid outlet hole (112), and the second groove cavity (12) is provided with a second liquid inlet hole (121) and a second liquid outlet hole (122); wherein, The first liquid inlet hole (111) is connected to the first container (21) via a first liquid inlet pipe (51), and the first liquid outlet hole (112) is connected to the first container (21) via a first liquid outlet pipe (52); the second liquid inlet hole (121) is connected to the second container (22) via a second liquid inlet pipe (53), and the second liquid outlet hole (122) is connected to the second container (22) via a second liquid outlet pipe (54).

3. The lithium extraction device according to claim 2, characterized in that: The second container (22) is connected to a third liquid inlet pipe (55) communicating therewith, and the first liquid inlet hole (111) can be selectively communicated with either the first liquid inlet pipe (51) or the third liquid inlet pipe (55) through a first valve (61); The first container (21) is connected to a third liquid outlet pipe (56) communicating therewith, and the first liquid outlet hole (112) can be selectively communicated with either the first liquid outlet pipe (52) or the third liquid outlet pipe (56) through a second valve (62); The first container (21) is connected to a fourth liquid inlet pipe (57) communicating therewith, and the second liquid inlet hole (121) can be selectively communicated with either the second liquid inlet pipe (53) or the fourth liquid inlet pipe (57) through a third valve (63); The second container (22) is connected to a fourth liquid outlet pipe (58) communicating therewith, and the second liquid outlet hole (122) can be selectively communicated with either the second liquid outlet pipe (54) or the fourth liquid outlet pipe (58) through a fourth valve (64).

4. The lithium extraction device according to claim 2 or 3, characterized in that: A basket (7) is placed in the first tank cavity (11), and the first current collector (41) and the lithium-deficient active material are placed in the basket (7); And / or, a basket (7) is placed in the second tank cavity (12), and the second current collector (42) and the lithium-rich active material are placed in the basket (7); The housing (7) is provided with a plurality of via holes (711), the inner cavity of the housing (7) is connected to the groove cavity where the housing (7) is located through the via holes (711), and the aperture of the via holes (711) is smaller than the particle diameter of the lithium-deficient active material and smaller than the particle diameter of the lithium-rich active material.

5. The lithium extraction device according to claim 4, characterized in that: The basket body (7) comprises two sub-basket parts (71), the two sub-basket parts (71) are connected to form a basket inner cavity with an open top, and a side wall of any sub-basket part (71) facing the corresponding current collector is provided with a plurality of the through holes (711); The first current collector (41) divides the corresponding inner cavity of the basket into two first compartments, and lithium-deficient active materials are provided in any of the first compartments; and / or the second current collector (42) divides the corresponding inner cavity of the basket into two second compartments, and lithium-rich active materials are provided in any of the second compartments.

6. The lithium extraction device according to claim 2 or 3, characterized in that: The first liquid inlet (111), the first liquid outlet (112), the second liquid inlet (121) and the second liquid outlet (122) are all provided with a filter screen (8), and the mesh diameter of the filter screen (8) is smaller than the particle diameter of the lithium-deficient active material and smaller than the particle diameter of the lithium-rich active material.

7. The lithium extraction device according to claim 6, characterized in that: The opposite side edges of the first liquid inlet hole (111) extend to the opposite sides of the first current collector (41) respectively, and the opposite sides of the first liquid outlet hole (112) extend to the opposite sides of the first current collector (41); And / or, the opposite side edges of the second liquid inlet hole (121) extend to the opposite sides of the second current collector (42), and the opposite side edges of the second liquid outlet hole (122) extend to the opposite sides of the second current collector (42).

8. The lithium extraction device according to claim 1, characterized in that: The first container (21) is provided with a first hole, the first hole having a first opening end surface facing the second container (22), a first sealing gasket (91) being provided between the first opening end surface and the anion membrane (3), And / or, the second container (22) is provided with a second hole, the second hole has a second opening end surface facing the first container (21), and a second sealing gasket (92) is provided between the second opening end surface of the first sealing gasket (91) and the anion membrane (3).

9. The lithium extraction device according to claim 1, characterized in that: The main tank body (1) comprises a main tank cavity, in which a plurality of partitions (13) are arranged at intervals, and the partitions (13) divide the main tank cavity into a plurality of the first tank cavities (11) and a plurality of the second tank cavities (12).

10. The lithium extraction device according to claim 9, characterized in that: The main tank body (1) and the partition plate (13) are integrally formed.

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