Electrochemical de-intercalation method lithium extraction system

Abstract

The utility model discloses a lithium extraction system adopting an electrochemical de-intercalation method. The lithium extraction system adopting the electrochemical de-intercalation method comprises a first de-intercalation groove, a first electrode arranged in the first de-intercalation groove and a first coating layer arranged on the first electrode, the second electrode is arranged in the second de-embedding groove; the second coating layer is arranged on the second electrode; and a first driving device and a second driving device. When the first electrode is used as a negative electrode and the second electrode is used as a positive electrode, the volume of a to-be-extracted lithium solution entering the first deintercalation groove within the same unit time is greater than the volume of a lithium-rich solution entering the second deintercalation groove; when the first electrode is used as a positive electrode and the second electrode is used as a negative electrode, the volume of the to-be-extracted lithium liquid entering the second deintercalation groove in the same unit time is greater than the volume of the lithium-rich liquid entering the first deintercalation groove; therefore, the energy consumption is reduced.

Description

Technical Field

[0001] The utility model relates to the field of lithium extraction from lithium-containing solutions, in particular to a lithium extraction system using an electrochemical deintercalation method. Background Art

[0002] The electrochemical deintercalation method for lithium extraction from salt lakes requires driving a pump to continuously deliver lithium-rich liquid from a lithium-rich liquid tank to a chamber provided with an anode for lithium deintercalation, and return the liquid in the chamber provided with the anode to the lithium-rich liquid tank; deliver the lithium liquid to be extracted from the lithium liquid tank to a chamber provided with a cathode for lithium intercalation, and return the liquid in the chamber provided with the cathode to the lithium liquid tank to be extracted; the solution circulates back and forth, and fresh lithium liquid to be extracted continuously reaches the cathode surface in the cathode chamber and is embedded in the lithium-deficient coating material coated on the cathode; in the anode chamber, lithium ions in the lithium-rich coating material coated on the anode are continuously deintercalated into the lithium-rich liquid, and the lithium ions deintercalated in the coating material are the lithium ions embedded from the lithium liquid to be extracted into the coating material in the last reaction process, and the deintercalation and intercalation processes are carried out simultaneously in the two chambers, ultimately achieving the separation and enrichment of lithium in the lithium liquid to be extracted.

[0003] Most of the power consumption of the electrochemical deintercalation lithium extraction process is consumed by the circulating drive pump to transport the liquid. The power consumption of the drive pump accounts for a relatively large proportion of the entire electrochemical deintercalation lithium extraction process. Utility Model Content

[0004] The embodiment of the utility model provides a lithium extraction system using an electrochemical deintercalation method to reduce energy consumption.

[0005] The purpose of this utility model is achieved by the following technical solutions:

[0006] The present invention provides an electrochemical deintercalation lithium extraction system, comprising a first deintercalation tank, a first electrode disposed in the first deintercalation tank, and a first coating layer disposed on the first electrode; a second deintercalation tank, a second electrode disposed in the second deintercalation tank, and a second coating layer disposed on the second electrode; and a first driving device and a second driving device;

[0007] When the first electrode is used as a negative electrode and the second electrode is used as a positive electrode, the first driving device is configured to input a lithium solution to be extracted into the first deintercalation tank, and the second driving device is configured to input a lithium-rich solution into the second deintercalation tank, and the volume of the lithium solution to be extracted entering the first deintercalation tank is greater than the volume of the lithium-rich solution entering the second deintercalation tank in the same unit time;

[0008] When the first electrode is used as a positive electrode and the second electrode is used as a negative electrode, the first driving device is configured to input a lithium solution to be extracted into the second deintercalation tank, and the second driving device is configured to input a lithium-rich solution into the first deintercalation tank, and the volume of the lithium solution to be extracted entering the second deintercalation tank is greater than the volume of the lithium-rich solution entering the first deintercalation tank in the same unit time.

[0009] In an exemplary embodiment, when the first electrode serves as a negative electrode and the second electrode serves as a positive electrode, the first driving device is configured to input a lithium solution to be extracted into the first deintercalation tank, and the first driving device has a first output power; the second driving device is configured to input a lithium-rich solution into the second deintercalation tank, and the second driving device has a second output power; the second output power is less than the first output power; when the first electrode serves as a positive electrode and the second electrode serves as a negative electrode, the first driving device is configured to input a lithium solution to be extracted into the second deintercalation tank, and the first driving device has a third output power; the second driving device is configured to input a lithium-rich solution into the first deintercalation tank, and the second driving device has a fourth output power; the fourth output power is less than the third output power.

[0010] In an exemplary embodiment, the fourth output power is less than the first output power; and / or the second output power is less than the third output power.

[0011] In an exemplary embodiment, the lithium solution to be extracted includes lithium ions, and the concentration of the lithium ions in the lithium solution to be extracted is greater than or equal to 0.32 g / L and less than or equal to 1.2 g / L.

[0012] In an exemplary embodiment, when the first electrode serves as a negative electrode and the second electrode serves as a positive electrode, the first driving device is configured to input a lithium solution to be extracted into the first deintercalation tank, and the first driving device has a first frequency; the second driving device is configured to input a lithium-rich solution into the second deintercalation tank, and the second driving device has a second frequency; and the second frequency is less than the first frequency.

[0013] In an exemplary embodiment, when the first electrode serves as a positive electrode and the second electrode serves as a negative electrode, the first driving device is configured to input a lithium solution to be extracted into the second deintercalation tank, and the first driving device has a third frequency; the second driving device is configured to input a lithium-rich solution into the first deintercalation tank, and the second driving device has a fourth frequency; the fourth frequency is less than the third frequency.

[0014] In the electrochemical deintercalation lithium extraction system of the utility model embodiment, the volume of the lithium solution to be extracted entering the first deintercalation tank in the same unit time is greater than the volume of the lithium-rich solution entering the second deintercalation tank, thereby achieving the purpose of energy saving.

[0015] In the electrochemical deintercalation lithium extraction system of the utility model embodiment, the volume of the lithium solution to be extracted entering the second deintercalation tank in the same unit time is greater than the volume of the lithium-rich solution entering the first deintercalation tank, thereby achieving the purpose of energy saving.

[0016] The electrochemical deintercalation lithium extraction system of the utility model embodiment achieves energy saving by making the second output power smaller than the first output power.

[0017] In the electrochemical deintercalation lithium extraction system of the utility model embodiment, the fourth output power is smaller than the third output power, thereby achieving the purpose of energy saving.

[0018] In the electrochemical deintercalation lithium extraction system of the utility model embodiment, the second frequency is lower than the first frequency, thereby achieving the purpose of energy saving.

[0019] In the electrochemical deintercalation lithium extraction system of the utility model embodiment, the fourth frequency is lower than the third frequency, thereby achieving energy saving.

[0020] Other features and advantages of the utility model will be described in the following description, and partly become apparent from the description, or understood by implementing the utility model. The purpose and other advantages of the utility model can be realized and obtained by the structures particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to provide a further understanding of the technical solution of the utility model and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the utility model and do not constitute a limitation on the technical solution of the utility model.

[0022] Figure 1 This is a schematic diagram of the structure of the electrochemical deintercalation lithium extraction system of the present application embodiment;

[0023] Figure 2 This is a schematic diagram of the principle structure of the deintercalation unit in the electrochemical deintercalation lithium extraction system of the embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the utility model more clear, the embodiments of the utility model will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

[0025] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. The terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0026] The inventor of the present application has found through research that the lithium extraction process by electrochemical deintercalation generally includes a forward reaction process and a reverse reaction process.

[0027] The forward reaction process is as follows: the first electrode in the first deintercalation tank is used as the positive electrode, the second electrode in the second deintercalation tank is used as the negative electrode, a lithium-rich solution is input into the first deintercalation tank through a second driving device, a power source is applied, and the lithium ions in the coating layer on the first electrode are deintercalated from the first coating layer and enter into the lithium-rich solution in the first deintercalation tank, thereby increasing the lithium ion content in the lithium-rich solution; correspondingly, a lithium solution to be extracted is input into the second deintercalation tank through the first driving device, and the lithium ions in the lithium solution to be extracted enter into the second coating layer of the second electrode from the lithium solution to be extracted, thereby increasing the lithium ion content in the second coating layer of the second electrode, reducing the lithium ion concentration in the lithium solution to be extracted, and achieving the purpose of lithium extraction.

[0028] The reverse reaction process is: first output the lithium-rich liquid in the first deintercalation tank to the lithium-rich liquid storage tank, and output the lithium liquid to be extracted in the second deintercalation tank to the lithium liquid storage tank; rinse the first and second deintercalation tanks, then use the first electrode in the first deintercalation tank as the negative electrode, use the second electrode in the second deintercalation tank as the positive electrode, input the lithium liquid to be extracted into the first deintercalation tank through the first driving device, power on, and the lithium ions in the lithium liquid to be extracted enter the first coating layer of the first electrode from the lithium liquid to be extracted, thereby increasing the content of lithium ions in the first coating layer of the first electrode and reducing the concentration of lithium ions in the solution; correspondingly, input the lithium-rich liquid into the second deintercalation tank through the second driving device, and the lithium ions in the second coating layer on the second electrode are extracted from the second coating layer and enter the lithium-rich liquid in the second deintercalation tank, thereby increasing the content of lithium ions in the lithium-rich liquid and achieving the purpose of lithium ion enrichment.

[0029] However, in the existing electrochemical deintercalation method for lithium extraction, the volumes of the first and second deintercalation tanks are substantially the same, the amounts of liquid input into the first and second deintercalation tanks are kept substantially the same, and the output powers of the first and second drive devices are generally selected to be substantially the same.

[0030] The present invention provides an electrochemical deintercalation lithium extraction system, comprising a first deintercalation tank, a first electrode disposed in the first deintercalation tank, and a first coating layer disposed on the first electrode; a second deintercalation tank, a second electrode disposed in the second deintercalation tank, and a second coating layer disposed on the second electrode; and a first driving device and a second driving device;

[0031] When the first electrode is used as a negative electrode and the second electrode is used as a positive electrode, the first driving device is configured to input a lithium solution to be extracted into the first deintercalation tank, and the second driving device is configured to input a lithium-rich solution into the second deintercalation tank, and the volume of the lithium solution to be extracted entering the first deintercalation tank is greater than the volume of the lithium-rich solution entering the second deintercalation tank in the same unit time;

[0032] When the first electrode is used as a positive electrode and the second electrode is used as a negative electrode, the first driving device is configured to input a lithium solution to be extracted into the second deintercalation tank, and the second driving device is configured to input a lithium-rich solution into the first deintercalation tank, and the volume of the lithium solution to be extracted entering the second deintercalation tank is greater than the volume of the lithium-rich solution entering the first deintercalation tank in the same unit time.

[0033] The solution of this embodiment is described below by means of some examples.

[0034] Figure 1 Schematic diagram of the structure of the electrochemical deintercalation lithium extraction system of the present application embodiment. In an exemplary embodiment, Figure 1 As shown, the electrochemical deintercalation lithium extraction system of the embodiment of the present application includes one or more deintercalation units 100, a lithium solution storage device 200, a lithium-rich solution storage device 300, a first driving device 31 and a second driving device 32.

[0035] In an exemplary embodiment, each deintercalation unit 100 includes one or more first deintercalation slots and one or more second deintercalation slots, the number of the first deintercalation slots and the number of the second deintercalation slots may be the same, and the first deintercalation slots and the second deintercalation slots are adjacently disposed with an ion membrane disposed therebetween.

[0036] In an exemplary embodiment, a first electrode is disposed in the first deintercalation tank, a first coating layer is disposed on the first electrode, the first coating layer can embed or extract lithium ions, and the first coating layer may include lithium iron phosphate embedded in or extracted lithium; when the first electrode is a positive electrode, the first coating layer is a coating layer including lithium iron phosphate, a lithium-rich solution is input into the first deintercalation tank, and lithium ions in the first coating layer on the first electrode are extracted from the first coating layer and enter the lithium-rich solution in the first deintercalation tank; when the first electrode is a negative electrode, the first coating layer is a lithium iron phosphate coating layer including extracted lithium, a lithium solution to be extracted is input into the first deintercalation tank, and lithium ions in the lithium solution to be extracted enter from the lithium solution to be extracted into the first coating layer of the first electrode.

[0037] In an exemplary embodiment, a second electrode is disposed in the second deintercalation tank, a second coating layer is disposed on the second electrode, the second coating layer can embed or extract lithium ions, and the second coating layer may include lithium iron phosphate embedded in or extracted lithium; when the second electrode is a positive electrode, the second coating layer is a coating layer including lithium iron phosphate, a lithium-rich solution is input into the second deintercalation tank, and lithium ions in the second coating layer on the second electrode are extracted from the second coating layer and enter the lithium-rich solution in the second deintercalation tank; when the second electrode is a negative electrode, the second coating layer is a lithium iron phosphate coating layer including extracted lithium, a lithium solution to be extracted is input into the second deintercalation tank, and lithium ions in the lithium solution to be extracted enter from the lithium solution to be extracted into the second coating layer of the second electrode.

[0038] In an exemplary embodiment, the polarities of the first electrode and the second electrode are opposite. For example, when the first electrode is positive, the second electrode is negative; or, when the first electrode is negative, the second electrode is positive.

[0039] In an exemplary embodiment, the deintercalation unit 100 further includes a first inlet 9 and a first outlet 102 connected to the first deintercalation tank, and a second inlet 10 and a second outlet 103 connected to the second deintercalation tank. The first inlet 9 is set as the inlet of the first deintercalation tank, and the lithium solution to be extracted or the lithium-rich solution can enter the first deintercalation tank through the first inlet 9; the first outlet 102 is set as the outlet of the first deintercalation tank, and the lithium solution to be extracted or the lithium-rich solution can flow out of the first deintercalation tank through the first outlet 102; the second inlet 10 is set as the inlet of the second deintercalation tank, and the lithium solution to be extracted or the lithium-rich solution can enter the second deintercalation tank through the second inlet 10; the second outlet 103 is set as the inlet of the second deintercalation tank, and the lithium solution to be extracted or the lithium-rich solution can flow out of the second deintercalation tank through the second outlet 103.

[0040] In an exemplary embodiment, the lithium liquid storage device 200 and the lithium-rich liquid storage device 300 are two independent containers. The lithium liquid storage device 200 is used to store the lithium liquid to be extracted, and the lithium-rich liquid storage device 300 is used to store the lithium-rich liquid.

[0041] In an exemplary embodiment, the first driving device 31 includes one or more first driving pumps. The input end of the first driving device 31 is connected to the output end of the lithium liquid storage device 200. The first driving device 31 is configured to transport the lithium liquid to be extracted in the lithium liquid storage device 200 to the first deintercalation tank or the second deintercalation tank of the deintercalation unit 100.

[0042] In an exemplary embodiment, the second driving device 32 includes one or more second driving pumps. The input end of the second driving device 32 is connected to the output end of the lithium-rich liquid storage device 300. The second driving device 32 is configured to transport the lithium-rich liquid in the lithium-rich liquid storage device 300 to the first deintercalation tank or the second deintercalation tank of the deintercalation unit 100.

[0043] In an exemplary embodiment, the electrochemical deintercalation lithium extraction system of the present application embodiment further includes a first liquid inlet pipeline 41 and a second liquid inlet pipeline 42. The input end of the first liquid inlet pipeline 41 is connected to the output end of the first driving device 31. The input end of the second liquid inlet pipeline 42 is connected to the output end of the second driving device 32.

[0044] In an exemplary embodiment, the electrochemical deintercalation lithium extraction system of the embodiment of the present application further includes a first control valve group 21, a third liquid inlet pipeline 43 and a fourth liquid inlet pipeline 44. The output ends of the first liquid inlet pipeline 41 and the second liquid inlet pipeline 42 are both connected to the first control valve group 21, and the input ends of the third liquid inlet pipeline 43 and the fourth liquid inlet pipeline 44 are both connected to the first control valve group 21. The first control valve group 21 can connect the first liquid inlet pipeline 41 with the third liquid inlet pipeline 43, and can connect the second liquid inlet pipeline 42 with the fourth liquid inlet pipeline 44; or, the first control valve group 21 can connect the first liquid inlet pipeline 41 with the fourth liquid inlet pipeline 44, and can connect the second liquid inlet pipeline 42 with the third liquid inlet pipeline 43.

[0045] In an exemplary embodiment, the first control valve group 21 includes a first input end, a second input end, a first output end, a second output end, a third output end, and a fourth output end. The first input end of the first control valve group 21 is connected to the output end of the first liquid inlet pipeline 41, and the second input end of the first control valve group 21 is connected to the output end of the second liquid inlet pipeline 42. The first output end and the second output end of the first control valve group 21 can be connected or disconnected with the output end of the first liquid inlet pipeline 41, and the third output end and the fourth output end of the first control valve group 21 can be connected or disconnected with the output end of the second liquid inlet pipeline 42. For example, the first output end of the first control valve group 21 can be connected to the output end of the first liquid inlet pipeline 41, and the second output end of the first control valve group 21 can be disconnected from the output end of the first liquid inlet pipeline 41, so that the lithium liquid to be extracted in the first liquid inlet pipeline 41 is output from the first output end; the fourth output end of the first control valve group 21 can be connected to the output end of the second liquid inlet pipeline 42, and the third output end of the first control valve group 21 can be disconnected from the output end of the second liquid inlet pipeline 42, so that the lithium-rich liquid in the second liquid inlet pipeline 42 is output from the fourth output end ; Alternatively, the second output end of the first control valve group 21 can be connected to the output end of the first liquid inlet pipeline 41, and the first output end of the first control valve group 21 can be disconnected from the output end of the first liquid inlet pipeline 41, so that the lithium liquid to be extracted in the first liquid inlet pipeline 41 is output from the second output end; the third output end of the first control valve group 21 can be connected to the output end of the second liquid inlet pipeline 42, and the fourth output end of the first control valve group 21 can be disconnected from the output end of the second liquid inlet pipeline 42, so that the lithium-rich liquid in the second liquid inlet pipeline 42 is output from the third output end.

[0046] In the exemplary embodiment, the input end of the third liquid inlet pipeline 43 is connected to the first output end and the third output end of the first control valve group 21, respectively, and the output end of the third liquid inlet pipeline 43 is connected to the first inlet 9 of the de-embedding unit 100. The input end of the fourth liquid inlet pipeline 44 is connected to the second output end and the fourth output end of the first control valve group 21, respectively, and the output end of the fourth liquid inlet pipeline 44 is connected to the second inlet 10 of the de-embedding unit 100.

[0047] In an exemplary embodiment, the electrochemical deintercalation lithium extraction system of the present application embodiment further includes a first liquid outlet pipe 51 and a second liquid outlet pipe 52. The input end of the first liquid outlet pipe 51 is connected to the first outlet 102 of the deintercalation unit 100, and the input end of the second liquid outlet pipe 52 is connected to the second outlet 103 of the deintercalation unit 100.

[0048] In an exemplary embodiment, the electrochemical deintercalation lithium extraction system of the present application embodiment further includes a second control valve group 22, a third liquid outlet pipeline 53 and a fourth liquid outlet pipeline 54. The output end of the third liquid outlet pipeline 53 is connected to the input end of the lithium liquid storage device 200 to be extracted, and the output end of the fourth liquid outlet pipeline 54 is connected to the input end of the lithium-rich liquid storage device 300. The output ends of the first liquid outlet pipeline 51 and the second liquid outlet pipeline 52 are both connected to the second control valve group 22, and the input ends of the third liquid outlet pipeline 53 and the fourth liquid outlet pipeline 54 are both connected to the second control valve group 22. The second control valve group 22 can connect the first liquid outlet pipeline 51 with the third liquid outlet pipeline 53, and can connect the second liquid outlet pipeline 52 with the fourth liquid outlet pipeline 54; or, the first control valve group 21 can connect the first liquid outlet pipeline 51 with the fourth liquid outlet pipeline 54, and can connect the second liquid outlet pipeline 52 with the third liquid outlet pipeline 53.

[0049] In an exemplary embodiment, the second control valve group 22 includes a first input end, a second input end, a first output end, a second output end, a third output end, and a fourth output end. The first input end of the second control valve group 22 is connected to the output end of the first liquid outlet pipe 51, and the second input end of the second control valve group 22 is connected to the output end of the second liquid outlet pipe 52. The first output end and the second output end of the second control valve group 22 can be connected or disconnected with the output end of the first liquid outlet pipe 51, and the third output end and the fourth output end of the second control valve group 22 can be connected or disconnected with the output end of the second liquid outlet pipe 52. For example, the first output end of the second control valve group 22 can be connected to the output end of the first liquid outlet pipeline 51, the fourth output end of the second control valve group 22 can be connected to the output end of the second liquid outlet pipeline 52, the second output end of the second control valve group 22 can be disconnected from the output end of the first liquid outlet pipeline 51, and the third output end of the second control valve group 22 can be disconnected from the output end of the second liquid outlet pipeline 52, so that the lithium liquid to be extracted in the first liquid outlet pipeline 51 is output from the first output end, and the lithium-rich liquid in the second liquid outlet pipeline 52 is output from the fourth output end ; Alternatively, the second output end of the second control valve group 22 can be connected to the output end of the first liquid outlet pipe 51, the third output end of the second control valve group 22 can be connected to the output end of the second liquid outlet pipe 52, the first output end of the second control valve group 22 can be disconnected from the output end of the first liquid outlet pipe 51, and the fourth output end of the second control valve group 22 can be disconnected from the output end of the second liquid outlet pipe 52, so that the lithium liquid to be extracted in the first liquid outlet pipe 51 is output from the second output end, and the lithium-rich liquid in the second liquid outlet pipe 52 is output from the third output end.

[0050] In an exemplary embodiment, the input end of the third liquid outlet pipe 53 is respectively connected to the first output end and the third output end of the second control valve group 22. The input end of the fourth liquid outlet pipe 54 is respectively connected to the second output end and the fourth output end of the second control valve group 22.

[0051] In an exemplary embodiment, the electrochemical deintercalation lithium extraction system of the utility model embodiment further includes a cleaning device 400, which is connected to the first deintercalation tank and the second deintercalation tank of the deintercalation unit 100, and a cleaning liquid is stored in the cleaning device 400. After the forward reaction process is completed and before the reverse reaction process begins, the cleaning liquid in the cleaning device 400 is transported to the first deintercalation tank and the second deintercalation tank to clean the first deintercalation tank and the second deintercalation tank to avoid impurities in the first deintercalation tank and the second deintercalation tank, which affect the reaction effect.

[0052] Figure 2 Schematic diagram of the principle structure of the deintercalation unit in the electrochemical deintercalation lithium extraction system of the present application embodiment. In an exemplary embodiment, Figure 2 As shown, the deintercalation unit in the electrochemical deintercalation lithium extraction system of this embodiment includes two end plates 101 arranged opposite to each other and a first deintercalation groove 2 and a second deintercalation groove 3 located between the two end plates 101. The two end plates 101 are squeezed into one by pressure to keep the first deintercalation groove and the second deintercalation groove from leaking. At least two first inlets 9, at least two first outlets 102, at least two second inlets 10 and at least two second outlets 103 are arranged on at least one of the end plates 101. Among them, the first inlet 9 and the second inlet 10 are arranged on the first side of the end plate 101, and the first outlet 102 and the second outlet 103 are arranged on the second side of the end plate 101; the first side and the second side are the opposite sides of the end plate 101 in the second direction. At least two first inlets 9 and at least two second inlets 10 are arranged at intervals along the first direction, and the first inlet 9 and the second inlet 10 are arranged overlappingly along the first direction. Among them, the first direction intersects with the second direction, and for example, the first direction is perpendicular to the second direction.

[0053] In an exemplary embodiment, the de-embedding unit includes a first de-embedding slot frame 104, a second de-embedding slot frame 105, and an anion membrane 106 located between the first de-embedding slot frame 104 and the second de-embedding slot frame 105. A cavity is provided in each of the first de-embedding slot frame 104 and the second de-embedding slot frame 105. The end plate 101 and the anion membrane 106 adjacent to the first de-embedding slot frame 104 clamp the cavity of the first de-embedding slot frame 104 to form a first de-embedding slot 2. The end plate 101 and the anion membrane 106 adjacent to the second de-embedding slot frame 105 clamp the cavity of the second de-embedding slot frame 105 to form a second de-embedding slot 3.

[0054] In an exemplary embodiment, a first electrode 4 is disposed in the first deintercalation tank 2, and a first coating layer is coated on the first electrode 4. When the first electrode 4 is a cathode, the first coating layer can be intercalated with lithium, and when the first electrode 4 is an anode, the first coating layer can be deintercalated with lithium. A second electrode 5 is disposed in the second deintercalation tank 3, and a second coating layer is coated on the second electrode 5. When the second electrode 5 is a cathode, the second coating layer can be intercalated with lithium, and when the second electrode 5 is an anode, the second coating layer can be deintercalated with lithium. The first coating layer may include lithium iron phosphate or iron phosphate; the second coating layer may include lithium iron phosphate or iron phosphate.

[0055] In an exemplary embodiment, the first ejection groove frame and the second ejection groove frame may have the same structure or may have different structures.

[0056] In an exemplary embodiment, a first input port 107 and a liquid inlet channel 108 are provided at one end of the first de-embedding tank frame 104, the first input port 107 is communicated with the first de-embedding tank 2 through the liquid inlet channel 108, and the first inlet 9 on the end plate 101 is communicated with the first input port 107. A first output port 109 and a liquid outlet channel 110 are provided at the other end of the first de-embedding tank frame 104, the first output port 109 is communicated with the first de-embedding tank 2 through the liquid outlet channel 110; the first outlet 102 on the end plate 101 is communicated with the first output port 109.

[0057] In an exemplary embodiment, a second input port 111 and a liquid inlet channel 108 are provided at one end of the second de-embedding tank frame 105, the second input port 111 is communicated with the second de-embedding tank 3 through the liquid inlet channel 108, and the second inlet 10 on the end plate 101 is communicated with the second input port 111. A second output port 112 and a liquid outlet channel 110 are provided at the other end of the second de-embedding tank frame 105, the second output port 112 is communicated with the second de-embedding tank 3 through the liquid outlet channel 110; the second outlet 103 on the end plate 101 is communicated with the second output port 112.

[0058] like Figure 1 As shown, the working process of the electrochemical deintercalation lithium extraction system of the utility model embodiment is as follows:

[0059] (1) Forward reaction process. The forward reaction process includes: using the first electrode of the first deintercalation tank in the deintercalation unit 100 as the positive electrode, and flowing the lithium-rich liquid in the lithium-rich liquid storage device 300 into the second liquid inlet pipe 42 through the second driving device 32; then, connecting the second liquid inlet pipe 42 with the third liquid inlet pipe 43 through the first control valve group 21, so that the lithium-rich liquid in the second liquid inlet pipe 42 flows into the third liquid inlet pipe 43; then, the lithium-rich liquid in the third liquid inlet pipe 43 enters the first deintercalation tank through the first inlet 9, and the first coating on the first electrode is The lithium ions in the coating are released from the first coating layer and enter the lithium-rich liquid in the first deintercalation tank, thereby increasing the lithium ion content in the lithium-rich liquid; then, the lithium-rich liquid in the first deintercalation tank enters the first liquid outlet pipe 51 through the first outlet 102; then, the first liquid outlet pipe 51 is connected to the fourth liquid outlet pipe 54 through the second control valve group 22, so that the lithium-rich liquid in the first liquid outlet pipe 51 flows into the fourth liquid outlet pipe 54; then, the lithium-rich liquid in the fourth liquid outlet pipe 54 flows into the lithium-rich liquid storage device 300.

[0060] At the same time, the second electrode of the second deintercalation tank in the intercalation unit 100 is used as the negative electrode, and the lithium solution to be extracted in the lithium solution storage device 200 is flowed into the first liquid inlet pipe 41 through the first driving device 31; then, the first liquid inlet pipe 41 is connected to the fourth liquid inlet pipe 44 through the first control valve group 21, so that the lithium solution to be extracted in the first liquid inlet pipe 41 flows into the fourth liquid inlet pipe 44; then, the lithium solution to be extracted in the fourth liquid inlet pipe 44 enters the second deintercalation tank through the second inlet 10, and the lithium ions in the lithium solution to be extracted in the second deintercalation tank are discharged from the first liquid inlet pipe 41; The lithium solution to be extracted enters the second coating layer of the second electrode, thereby increasing the content of lithium ions in the second coating layer of the second electrode; then, the lithium solution to be extracted in the second deintercalation tank enters the second liquid outlet pipe 52 through the second outlet 103; then, the second liquid outlet pipe 52 is connected to the third liquid outlet pipe 53 through the second control valve group 22, so that the lithium solution to be extracted in the second liquid outlet pipe 52 flows into the third liquid outlet pipe 53; then, the lithium solution to be extracted in the third liquid outlet pipe 53 flows into the lithium solution storage device 200 to complete a forward cycle.

[0061] (2) Reverse reaction process. The reverse reaction process includes: using the second electrode of the second deintercalation tank in the deintercalation unit 100 as the positive electrode, and flowing the lithium-rich liquid in the lithium-rich liquid storage device 300 into the second liquid inlet pipe 42 through the second driving device 32; then, connecting the second liquid inlet pipe 42 with the fourth liquid inlet pipe 44 through the first control valve group 21, so that the lithium-rich liquid in the second liquid inlet pipe 42 flows into the fourth liquid inlet pipe 44; then, the lithium-rich liquid in the fourth liquid inlet pipe 44 enters the second deintercalation tank through the second inlet 10, and the second electrode on the second electrode is connected to the second liquid inlet pipe 42. The lithium ions in the coating layer are released from the second coating layer and enter the lithium-rich liquid in the second deintercalation tank, thereby increasing the lithium ion content in the lithium-rich liquid; then, the lithium-rich liquid in the second deintercalation tank enters the second liquid outlet pipe 52 through the second outlet 103; then, the second liquid outlet pipe 52 is connected to the fourth liquid outlet pipe 54 through the second control valve group 22, so that the lithium-rich liquid in the second liquid outlet pipe 52 flows into the fourth liquid outlet pipe 54; then, the lithium-rich liquid in the fourth liquid outlet pipe 54 flows into the lithium-rich liquid storage device 300.

[0062] At the same time, the first electrode of the first deintercalation tank in the deintercalation unit 100 is used as the negative electrode, and the lithium solution to be extracted in the lithium solution storage device 200 is flowed into the first liquid inlet pipe 41 through the first driving device 31; then, the first liquid inlet pipe 41 is connected to the third liquid inlet pipe 43 through the first control valve group 21, so that the lithium solution to be extracted in the first liquid inlet pipe 41 flows into the third liquid inlet pipe 43; then, the lithium solution to be extracted in the third liquid inlet pipe 43 enters the first deintercalation tank through the first inlet 9, and the lithium ions in the lithium solution to be extracted in the first deintercalation tank are discharged from the first inlet pipe 43. The lithium solution to be extracted enters the first coating layer of the first electrode, thereby increasing the content of lithium ions in the first coating layer of the first electrode; then, the lithium solution to be extracted in the first deintercalation tank enters the first liquid outlet pipe 51 through the first outlet 102; then, the first liquid outlet pipe 51 is connected to the third liquid outlet pipe 53 through the second control valve group 22, so that the lithium solution to be extracted in the first liquid outlet pipe 51 flows into the third liquid outlet pipe 53; then, the lithium solution to be extracted in the third liquid outlet pipe 53 flows into the lithium solution storage device 200 to complete a reverse cycle.

[0063] In an exemplary embodiment, during the reverse reaction process of the above-mentioned electrochemical deintercalation lithium extraction system, when the first electrode is used as the negative electrode and the second electrode is used as the positive electrode, the first driving device 31 is configured to input the lithium solution to be extracted into the first deintercalation tank, and the first driving device 31 has a first output power; the second driving device 32 is configured to input the lithium-rich solution into the second deintercalation tank, and the second driving device 32 has a second output power, and the second output power is less than the first output power. Among them, the first output power is the power per unit time when the first driving device 31 inputs the lithium solution to be extracted into the first deintercalation tank, and the second output power is the power per unit time when the second driving device 32 inputs the lithium-rich solution into the second deintercalation tank.

[0064] The electrochemical deintercalation lithium extraction system of the utility model embodiment makes the second output power smaller than the first output power, thereby reducing energy consumption compared with an electrochemical deintercalation lithium extraction system having the same first output power and second output power, thereby achieving energy saving.

[0065] In an exemplary embodiment, during the forward reaction of the above-mentioned electrochemical deintercalation lithium extraction system, when the first electrode is used as the positive electrode and the second electrode is used as the negative electrode, the first driving device 31 is configured to input the lithium solution to be extracted into the second deintercalation tank, and the first driving device 31 has a third output power; the second driving device 32 is configured to input the lithium-rich solution into the first deintercalation tank, and the second driving device 32 has a fourth output power, and the fourth output power is less than the third output power. Among them, the third output power is the power per unit time when the first driving device 31 inputs the lithium solution to be extracted into the second deintercalation tank, and the fourth output power is the power per unit time when the second driving device 32 inputs the lithium-rich solution into the first deintercalation tank.

[0066] In the embodiment of the utility model, the electrochemical deintercalation lithium extraction system has the fourth output power being less than the third output power, so that the energy consumption of the electrochemical deintercalation lithium extraction system is reduced, thereby achieving the purpose of energy saving.

[0067] In an exemplary embodiment, the fourth output power is less than the first output power; and / or the second output power is less than the third output power.

[0068] In the embodiment of the utility model, the electrochemical deintercalation lithium extraction system reduces energy consumption by setting the fourth output power to be less than the first output power; and / or the second output power to be less than the third output power, thereby achieving energy saving.

[0069] In an exemplary embodiment, the lithium solution to be extracted includes lithium ions, and the concentration of the lithium ions in the lithium solution to be extracted is greater than or equal to 0.32 g / L and less than or equal to 1.2 g / L. For example, the lithium solution to be extracted includes a mixed solution of sodium chloride and lithium chloride, the concentration of lithium ions in the lithium solution to be extracted is 0.5 g / L to 1 g / L, and the concentration of sodium ions in the lithium solution to be extracted is 5 g / L to 10 g / L.

[0070] In an exemplary embodiment, the lithium-rich solution includes a mixture of sodium chloride and lithium chloride, and the concentration of lithium ions in the lithium-rich solution is greater than or equal to 0.3 g / L and less than or equal to 2.06 g / L. For example, the lithium-rich solution includes a mixture of sodium chloride and lithium chloride, the concentration of lithium ions in the lithium-rich solution is 0.5 g / L to 1.5 g / L, and the concentration of sodium ions in the lithium-rich solution is 5 to 10 g / L.

[0071] In an exemplary embodiment, during the reverse reaction process of the above-mentioned electrochemical deintercalation lithium extraction system, when the first electrode is used as the negative electrode and the second electrode is used as the positive electrode, the first driving device transports the lithium solution to be extracted to the first deintercalation tank through the first liquid inlet pipe 41, and the flow rate of the lithium solution to be extracted in the first liquid inlet pipe 41 is the first flow rate; the second driving device 32 transports the lithium-rich solution to the second deintercalation tank through the second liquid inlet pipe 42, and the flow rate of the lithium-rich solution in the second liquid inlet pipe 42 is the second flow rate. The diameter of the first liquid inlet pipe 41 is the same as the diameter of the second liquid inlet pipe 42, the first flow rate is greater than the second flow rate, and the volume of the lithium solution to be extracted entering the first deintercalation tank in the same unit time is greater than the volume of the lithium-rich solution entering the second deintercalation tank.

[0072] The electrochemical deintercalation lithium extraction system of the utility model embodiment achieves energy saving by making the volume of the lithium solution to be extracted entering the first deintercalation tank greater than the volume of the lithium-rich solution entering the second deintercalation tank in the same unit time.

[0073] In an exemplary embodiment, during the forward reaction of the above-mentioned electrochemical deintercalation lithium extraction system, when the first electrode is used as the positive electrode and the second electrode is used as the negative electrode, the second driving device delivers the lithium-rich solution to the first deintercalation tank through the second liquid inlet pipe 42, and the flow rate of the lithium-rich solution in the second liquid inlet pipe 42 is the fourth flow rate; the first driving device 31 delivers the lithium solution to be extracted to the second deintercalation tank through the first liquid inlet pipe 41, and the flow rate of the lithium solution to be extracted in the second liquid inlet pipe 42 is the third flow rate. The diameter of the first liquid inlet pipe 41 is the same as the diameter of the second liquid inlet pipe 42, the third flow rate is greater than the fourth flow rate, and the volume of the lithium solution to be extracted entering the second deintercalation tank in the same unit time is greater than the volume of the lithium-rich solution entering the first deintercalation tank.

[0074] In the electrochemical deintercalation lithium extraction system of the utility model embodiment, the volume of the lithium solution to be extracted entering the second deintercalation tank in the same unit time is greater than the volume of the lithium-rich solution entering the first deintercalation tank, thereby achieving energy saving.

[0075] In an exemplary embodiment, the third flow rate is greater than the second flow rate; and / or the first flow rate is greater than the fourth flow rate.

[0076] In an exemplary embodiment, during the reverse reaction process of the above-mentioned electrochemical deintercalation lithium extraction system, when the first electrode serves as the negative electrode and the second electrode serves as the positive electrode, the lithium solution to be extracted is transported to the first deintercalation tank by the first driving device 31, and the frequency of the first driving device 31 is the first frequency; the lithium-rich solution is transported to the second deintercalation tank by the second driving device 32, and the frequency of the second driving device 32 is the second frequency, and the second frequency is less than the first frequency.

[0077] In the embodiment of the utility model, the electrochemical deintercalation lithium extraction system reduces the operating energy consumption of the electrochemical deintercalation lithium extraction system by making the second frequency smaller than the first frequency, thereby achieving energy saving.

[0078] In an exemplary embodiment, during the forward reaction process of the above-mentioned electrochemical deintercalation lithium extraction system, when the first electrode serves as the positive electrode and the second electrode serves as the negative electrode, the lithium-rich liquid is transported to the first deintercalation tank by the second driving device 32, and the frequency of the second driving device 32 is the fourth frequency; the lithium liquid to be extracted is transported to the second deintercalation tank by the first driving device 31, and the frequency of the first driving device 31 is the third frequency; the fourth frequency is less than the third frequency.

[0079] In the embodiment of the utility model, the electrochemical deintercalation method lithium extraction system has the fourth frequency being lower than the third frequency, so that the operating energy consumption of the electrochemical deintercalation method lithium extraction system is reduced, thereby achieving the purpose of energy saving.

[0080] In an exemplary embodiment, the fourth frequency is lower than the first frequency; and / or the second frequency is lower than the third frequency.

[0081] The electrochemical deintercalation lithium extraction system of the utility model embodiment achieves energy saving by making the fourth frequency lower than the first frequency; and / or the second frequency lower than the third frequency.

[0082] Comparative experiment 1

[0083] by Figure 1The electrochemical deintercalation lithium extraction system shown in the figure is used as an example for comparative experiments. The deintercalation unit includes 20 first deintercalation slots and 20 second deintercalation slots, and the first deintercalation slots and the second deintercalation slots are arranged alternately, that is, the first deintercalation slots and the second deintercalation slots in the deintercalation unit are arranged adjacent to each other. A first electrode is arranged in each first deintercalation slot, and the effective cross-sectional area of ​​each first electrode is 1 square meter; a second electrode is arranged in each second deintercalation slot, and the effective cross-sectional area of ​​each second electrode is 1 square meter. The first deintercalation slot and the second deintercalation slot constitute a lithium extraction deintercalation unit. The material of the first coating layer on the first electrode includes lithium iron phosphate ion sieve. The material of the second coating layer on the second electrode includes lithium iron phosphate. A storage device for lithium-rich liquid and lithium liquid to be extracted of the same volume is provided, the ambient temperature is 12°, the lithium-rich liquid storage device is provided with lithium-rich liquid, the lithium-rich liquid includes a mixed liquid of sodium chloride and lithium chloride, the volume of the lithium-rich liquid is 2 cubic meters, the concentration of lithium ions in the mixed liquid is 1.2 g / L, and the concentration of sodium ions in the mixed liquid is 10 g / L: the storage device for lithium liquid to be extracted is provided with lithium liquid to be extracted, the volume of the lithium liquid to be extracted is 2 cubic meters, the lithium liquid to be extracted includes a mixed liquid of sodium chloride and lithium chloride, the concentration of lithium ions in the mixed liquid is 1.2 g / L, and the concentration of sodium ions in the mixed liquid is 10 g / L. The first drive device is connected to the storage device for the lithium liquid to be extracted, the first drive device adopts a 4kW centrifugal pump, the first drive device is connected to the first liquid inlet pipe 41, and the lithium liquid to be extracted is transported to the first deintercalation tank through the first liquid inlet pipe 41; the second drive device is connected to the lithium-rich liquid storage device, the second drive device adopts a 4kW centrifugal pump, the second drive device is connected to the second liquid inlet pipe 42, and the lithium-rich liquid is transported to the second deintercalation tank through the second liquid inlet pipe 42. Among them, the deintercalation unit applies power to work and outputs in a multi-stage constant current mode. The lithium-rich liquid storage device and the lithium liquid storage device to be extracted are connected to each other.

[0084] It should be noted that when the deintercalation cell is working to extract lithium, the positive electrode of the power supply is connected to the electrode on the lithium-rich liquid side, and the negative electrode is connected to the electrode on the lithium-extraction liquid side.

[0085] Reverse reaction process: the first electrode is used as the negative electrode, the first driving device 31 uses an output power of 4kW, and inputs the lithium solution to be extracted from the lithium solution storage device 200 into the first deintercalation tank, so that the lithium solution to be extracted in the first deintercalation tank reacts with the first coating layer on the first electrode. The second electrode is used as the positive electrode, the second driving device 32 uses an output power of 4kW, and inputs the lithium-rich solution from the lithium-rich solution storage device 300 into the second deintercalation tank, the second coating layer on the second electrode reacts, and lithium ions enter the lithium-rich solution side solution.

[0086] During the reverse reaction, the working current of the deintercalation unit is shown in Table 1.

[0087] Table 1

[0088]

[0089] The first stripping tank and the second stripping tank are rinsed.

[0090] Forward reaction process: the first electrode is used as the positive electrode, the second electrode is used as the negative electrode, the second driving device 32 uses the fourth output power of 2kW, and inputs the lithium-rich liquid of the lithium-rich liquid storage device 300 into the first deintercalation tank, so that the lithium-rich liquid in the first deintercalation tank undergoes an oxidation reaction with the first coating layer on the first electrode, and lithium ions enter the lithium-rich liquid. The first driving device 31 uses the third output power of 4kW, and inputs the lithium liquid to be extracted from the lithium liquid storage device 200 into the second deintercalation tank, so that the lithium liquid to be extracted in the second deintercalation tank undergoes a reduction reaction with the second coating layer on the second electrode, so that lithium ions are embedded in the coating layer. The working current of the deintercalation unit is maintained at 300A, and the total lithium extraction capacity of the entire deintercalation unit is 10*300=3000Ah in the ten hours from 8:00 to 18:00.

[0091] During the forward reaction, the working current of the deintercalation unit is shown in Table 2.

[0092] Table 2

[0093]

[0094] From the above experiment, it can be seen that when the power of the second driving device changes from 4kW to 2kW, that is, by reducing the output power of the second driving device 32, the efficiency of the entire deintercalation unit can still be kept unchanged, the working current is maintained at 300A, and the lithium extraction capacity of the entire deintercalation unit is maintained at 10*300=3000Ah in the ten hours from 8:00 to 18:00.

[0095] Comparative experiment 2

[0096] by Figure 1The electrochemical deintercalation lithium extraction system shown in the figure is used as an example for comparative experiments. The deintercalation unit includes 20 first deintercalation slots and 20 second deintercalation slots, and the first deintercalation slots and the second deintercalation slots are arranged alternately, that is, the first deintercalation slots and the second deintercalation slots in the deintercalation unit are arranged adjacent to each other. A first electrode is arranged in each first deintercalation slot, and the effective cross-sectional area of ​​each first electrode is 1 square meter; a second electrode is arranged in each second deintercalation slot, and the effective cross-sectional area of ​​each second electrode is 1 square meter. The first deintercalation slot and the second deintercalation slot constitute a lithium extraction deintercalation unit. The material of the first coating layer on the first electrode includes lithium iron phosphate ion sieve. The material of the second coating layer on the second electrode includes lithium iron phosphate. A storage device for lithium-rich liquid and lithium liquid to be extracted of the same volume is provided, the ambient temperature is 12°, the lithium-rich liquid storage device is provided with lithium-rich liquid, the lithium-rich liquid includes a mixed liquid of sodium chloride and lithium chloride, the volume of the lithium-rich liquid is 2 cubic meters, the concentration of lithium ions in the mixed liquid is 1.2 g / L, and the concentration of sodium ions in the mixed liquid is 10 g / L: The storage device for lithium liquid to be extracted is provided with lithium liquid to be extracted, the volume of the lithium liquid to be extracted is 2 cubic meters, the lithium liquid to be extracted includes a mixed liquid of sodium chloride and lithium chloride, the concentration of lithium ions in the mixed liquid is 1.2 g / L, and the concentration of sodium ions in the mixed liquid is 10 g / L. A first drive device is connected to the storage device for lithium liquid to be extracted, the first drive device is connected to the first liquid inlet pipeline 41, and the lithium liquid to be extracted is transported to the first de-embedding tank through the first liquid inlet pipeline 41; a second drive device is connected to the storage device for lithium-rich liquid, the second drive device is connected to the second liquid inlet pipeline 42, and the lithium-rich liquid is transported to the second de-embedding tank through the second liquid inlet pipeline 42. The de-embedding unit applies power and outputs a multi-stage constant current mode. The lithium-rich liquid storage device and the lithium liquid storage device to be extracted are connected to each other.

[0097] It should be noted that when the deintercalation cell is working to extract lithium, the positive electrode of the power supply is connected to the electrode on the lithium-rich liquid side, and the negative electrode is connected to the electrode on the lithium-extraction liquid side.

[0098] Reverse reaction process: the first electrode is used as the negative electrode, the second electrode is used as the positive electrode, the first driving device transports the lithium solution to be extracted to the first deintercalation tank through the first liquid inlet pipe 41, and the flow rate of the lithium solution to be extracted in the first liquid inlet pipe 41 is the first flow rate; the second driving device 32 transports the lithium-rich solution to the second deintercalation tank through the second liquid inlet pipe 42, and the flow rate of the lithium-rich solution in the second liquid inlet pipe 42 is the second flow rate. The diameter of the first liquid inlet pipe 41 is the same as the diameter of the second liquid inlet pipe 42.

[0099] During the reverse reaction, the current of the deintercalation unit is shown in Table 3.

[0100] Table 3

[0101]

[0102] It can be seen from Table 3 that in the reverse reaction process, the first flow rate is almost the same as the second flow rate, that is, the volume of the lithium solution to be extracted entering the first deintercalation tank in the same unit time is almost the same as the volume of the lithium-rich solution entering the second deintercalation tank. The working current of the deintercalation unit is maintained at 300A. In the ten hours from 8:00 to 18:00, the lithium extraction capacity of the entire deintercalation unit is maintained at 10*300=3000Ah.

[0103] The first stripping tank and the second stripping tank of the stripping unit are rinsed.

[0104] Forward reaction process: the first electrode is used as the positive electrode, and the second driving device 32 delivers the lithium-rich liquid to the first deintercalation tank through the second liquid inlet pipe 42, and the flow rate of the lithium-rich liquid in the second liquid inlet pipe 42 is the fourth flow rate; the second electrode is used as the negative electrode, and the first driving device 31 delivers the lithium liquid to be extracted to the second deintercalation tank through the first liquid inlet pipe 41, and the flow rate of the lithium liquid to be extracted in the second liquid inlet pipe 42 is the third flow rate, which is greater than the fourth flow rate. Among them, the diameter of the first liquid inlet pipe 41 is the same as the diameter of the second liquid inlet pipe 42, and the volume of the lithium liquid to be extracted entering the second deintercalation tank in the same unit time is greater than the volume of the lithium-rich liquid entering the first deintercalation tank.

[0105] During the forward reaction, the working current of the deintercalation unit is shown in Table 4.

[0106] Table 4

[0107]

[0108] It can be seen from Table 4 that in the forward reaction process, the third flow rate of the lithium solution to be extracted in the first liquid inlet pipe 41 is greater than the fourth flow rate of the lithium-rich solution in the second liquid inlet pipe 42, and the volume of the lithium solution to be extracted entering the second deintercalation tank in the same unit time is greater than the volume of the lithium-rich solution entering the first deintercalation tank. The working current is maintained at 300A, and within ten hours from 8:00 to 18:00, the lithium extraction capacity of the entire deintercalation unit remains at 10*300=3000Ah. It can be seen that by reducing the fourth flow rate, the volume of the lithium solution to be extracted entering the second deintercalation tank in the same unit time is greater than the volume of the lithium-rich solution entering the first deintercalation tank, and the lithium extraction efficiency of the entire deintercalation unit can still be kept unchanged (3000Ah), that is, it will not affect the chemical reaction rate in the deintercalation unit. Compared with the above-mentioned reverse reaction process, the power energy consumption of the deintercalation unit is reduced.

[0109] Comparative experiment 3

[0110] by Figure 1The electrochemical deintercalation lithium extraction system shown in the figure is used as an example for comparative experiments. The deintercalation unit includes 20 first deintercalation slots and 20 second deintercalation slots, and the first deintercalation slots and the second deintercalation slots are arranged alternately, that is, the first deintercalation slots and the second deintercalation slots in the deintercalation unit are arranged adjacent to each other. A first electrode is arranged in each first deintercalation slot, and the effective cross-sectional area of ​​each first electrode is 1 square meter; a second electrode is arranged in each second deintercalation slot, and the effective cross-sectional area of ​​each second electrode is 1 square meter. The first deintercalation slot and the second deintercalation slot constitute a lithium extraction deintercalation unit. The material of the first coating layer on the first electrode includes lithium iron phosphate ion sieve. The material of the second coating layer on the second electrode includes lithium iron phosphate. A storage device for lithium-rich liquid and lithium liquid to be extracted having the same volume is provided, the ambient temperature is 12°, the lithium-rich liquid storage device is provided with lithium-rich liquid, the lithium-rich liquid includes a mixed liquid of sodium chloride and lithium chloride, the volume of the lithium-rich liquid is 2 cubic meters, the concentration of lithium ions in the mixed liquid is 1.2 g / L, and the concentration of sodium ions in the mixed liquid is 10 g / L: the storage device for lithium liquid to be extracted is provided with lithium liquid to be extracted, the volume of the lithium liquid to be extracted is 2 cubic meters, the lithium liquid to be extracted includes a mixed liquid of sodium chloride and lithium chloride, the concentration of lithium ions in the mixed liquid is 1.2 g / L, and the concentration of sodium ions in the mixed liquid is 10 g / L. The first drive device is connected to the storage device for the lithium liquid to be extracted, the first drive device adopts a 4kW centrifugal pump controlled by a frequency converter, the first drive device is connected to the first liquid inlet pipe 41, and the lithium liquid to be extracted is transported to the first de-embedding tank through the first liquid inlet pipe 41; the second drive device is connected to the storage device for the lithium-rich liquid, the second drive device adopts a 4kW centrifugal pump controlled by a frequency converter, the second drive device is connected to the second liquid inlet pipe 42, and the lithium-rich liquid is transported to the second de-embedding tank through the second liquid inlet pipe 42. The de-embedding unit applies power to work and outputs in a multi-stage constant current mode. The lithium-rich liquid storage device and the lithium liquid storage device to be extracted are connected to each other.

[0111] It should be noted that when the deintercalation cell is working to extract lithium, the positive electrode of the power supply is connected to the electrode on the lithium-rich liquid side, and the negative electrode is connected to the electrode on the lithium-extraction liquid side.

[0112] Reverse reaction process: the first electrode is used as the negative electrode, and the lithium solution to be extracted is transported to the first deintercalation tank through the first driving device 31, and the frequency converter corresponding to the first driving device 31 is set to the first frequency 40Hz; the second electrode is used as the positive electrode, and the lithium-rich solution is transported to the second deintercalation tank through the second driving device 32, and the driving frequency converter corresponding to the second driving device 32 is set to the second frequency 40Hz.

[0113] During the reverse reaction, the working current of the deintercalation unit is shown in Table 5.

[0114] Table 5

[0115]

[0116]

[0117] It can be seen from Table 5 that during the reverse reaction, the first frequency of the first driving device 31 is the same as the second frequency of the second driving device 32, the working current of the deintercalation unit is maintained at 300A, and the lithium extraction capacity of the entire deintercalation unit is maintained at 10*300=3000Ah within ten hours from 8:00 to 18:00.

[0118] The first stripping tank and the second stripping tank are rinsed.

[0119] Forward reaction process: the first electrode is used as the positive electrode, and the lithium-rich liquid is transported to the first deintercalation tank through the second driving device 32, and the frequency converter frequency corresponding to the second driving device 32 is the fourth frequency 32Hz; the second electrode is used as the negative electrode, and the lithium liquid to be extracted is transported to the second deintercalation tank through the first driving device 31, and the frequency converter frequency corresponding to the first driving device 31 is the third frequency 40Hz.

[0120] During the forward reaction, the working current of the deintercalation unit is shown in Table 6.

[0121] Table 6

[0122]

[0123] It can be seen from Table 6 that in the forward reaction process, the third frequency of the first drive device 31 is greater than the fourth frequency of the second drive device 32, and the working current of the deintercalation unit remains at 300A. In the ten hours from 8:00 to 18:00, the lithium extraction capacity of the entire deintercalation unit remains at 10*300=3000Ah. It can be seen that in the reaction process, by setting the fourth frequency to be less than the third frequency, the lithium extraction efficiency of the entire deintercalation unit can still be kept unchanged (3000Ah), that is, this measure does not affect the chemical reaction speed in the deintercalation unit, and compared with the above-mentioned reverse reaction process, the power consumption of the deintercalation unit is reduced.

[0124] Comparative experiment 4

[0125] The experimental conditions of comparative experiment 4 are basically the same as those of comparative experiment 1, except that the volume of lithium liquid to be extracted in the lithium liquid storage device is 1 cubic meter, the concentration of lithium ions in the lithium liquid to be extracted is 1.2 g / L, and the concentration of sodium ions in the lithium liquid to be extracted is 10 g / L; the volume of lithium-rich liquid in the lithium-rich liquid storage device is 0.5 cubic meter, the concentration of lithium ions in the lithium-rich liquid is 0.3 g / L, and the concentration of sodium ions in the lithium-rich liquid is 10 g / L; the lithium-rich liquid storage device and the lithium liquid storage device are not connected; the driving power of the first and second driving devices is set according to the following conditions.

[0126] It should be noted that when the deintercalation cell is working normally, the positive electrode of the power supply is connected to the electrode on the lithium-rich liquid side, and the negative electrode is connected to the electrode on the lithium extraction liquid side.

[0127] Reverse reaction process: the first electrode is used as the negative electrode and the second electrode is used as the positive electrode. The lithium solution to be extracted is transported to the first deintercalation tank by the first driving device 31, and the power of the first driving device 31 is the first output power; the lithium-rich solution is transported to the second deintercalation tank by the second driving device 32, and the power of the second driving device 32 is the second output power; the power of the first driving device 31 is 4kW, and the power of the second driving device 32 is 2kW.

[0128] The experimental results are shown in Table 4-1.

[0129] Table 4-1 Comparative Experiment 4 Lithium Concentration Change (Lithium Extraction Capacity 3400Ah)

[0130]

[0131] The first stripping tank and the second stripping tank are rinsed.

[0132] Forward reaction process: adjust the polarity of the power supply so that the first electrode is used as the positive electrode, and the lithium-rich liquid in the lithium-rich liquid storage device is transported to the first deintercalation tank through the second driving device 32; the second electrode is used as the negative electrode, and the lithium-rich liquid in the lithium-rich liquid storage device is transported to the second deintercalation tank through the first driving device 31. Among them, the volume of the lithium-rich liquid in the lithium-rich liquid storage device is 1 cubic meter, the concentration of lithium ions in the lithium-rich liquid is 1.2 grams per liter, and the concentration of sodium ions in the lithium-rich liquid is 10 grams per liter. The volume of the lithium-rich liquid in the lithium-rich liquid storage device is 0.5 cubic meters, the concentration of lithium ions in the lithium-rich liquid is 0.3 grams per liter, and the concentration of sodium ions in the lithium-rich liquid is 10 grams per liter; the power of the first driving device 31 is 4kW, and the power of the second driving device 32 is 4kW.

[0133] The experimental results are shown in Table 4-2.

[0134] Table 4-2 Comparative Experiment 4 Lithium Concentration Change (Lithium Extraction Capacity 3400Ah)

[0135]

[0136] It can be seen from Table 4-1 and Table 4-2 that when the first driving device 31 has the same power and the power of the second driving device 32 is changed from 2kW to 4kW, the amount of lithium extracted by the deintercalation unit from the lithium solution to be extracted is equal; the increase in the concentration of the lithium-rich solution after lithium extraction is also basically equal.

[0137] It can be seen from this that by setting the power of the second driving device (lithium-rich liquid side) to be lower than the driving output power of the first driving device (lithium liquid side to be extracted), the lithium extraction effect of the deintercalation unit can still be maintained unchanged, and the power consumption of the deintercalation unit can be reduced.

[0138] The present utility model also provides a method for extracting lithium from an electrochemical deintercalation lithium extraction system, wherein the electrochemical deintercalation lithium extraction system comprises a first deintercalation tank, a first electrode disposed in the first deintercalation tank, and a first coating layer disposed on the first electrode; a second deintercalation tank, a second electrode disposed in the second deintercalation tank, and a second coating layer disposed on the second electrode; and a first driving device and a second driving device;

[0139] The lithium extraction method of the electrochemical deintercalation lithium extraction system comprises:

[0140] When the first electrode is used as a negative electrode and the second electrode is used as a positive electrode, a lithium solution to be extracted is input into the first deintercalation tank through a first driving device, and a lithium-rich solution is input into the second deintercalation tank through a second driving device;

[0141] The first driving device has a first output power, and the second driving device has a second output power; the second output power is less than the first output power;

[0142] When the first electrode is used as a positive electrode and the second electrode is used as a negative electrode, the first driving device is configured to input the lithium solution to be extracted into the second deintercalation tank, and the second driving device is configured to input the lithium-rich solution into the first deintercalation tank;

[0143] The first driving device has a third output power, and the second driving device has a fourth output power; the fourth output power is less than the third output power.

[0144] In an exemplary embodiment, the lithium extraction method of the electrochemical deintercalation lithium extraction system is:

[0145] When the first electrode is used as a negative electrode and the second electrode is used as a positive electrode, the volume of the lithium solution to be extracted entering the first deintercalation tank is greater than the volume of the lithium-rich solution entering the second deintercalation tank in the same unit time.

[0146] In an exemplary embodiment, the lithium extraction method of the electrochemical deintercalation lithium extraction system is as follows: when the first electrode serves as a negative electrode and the second electrode serves as a positive electrode, the first driving device has a first frequency, and the second driving device has a second frequency, and the second frequency is less than the first frequency.

[0147] Although the implementation methods disclosed in the utility model are as above, the above contents are only implementation methods adopted to facilitate the understanding of the utility model, and are not used to limit the utility model. Any technician in the field to which the utility model belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the utility model, but the scope of patent protection of the utility model shall still be defined by the attached claims.

Claims

1. An electrochemical deintercalation lithium extraction system, characterized in that: It includes a first deintercalation groove, a first electrode disposed in the first deintercalation groove, and a first coating layer disposed on the first electrode; a second deintercalation groove, a second electrode disposed in the second deintercalation groove, and a second coating layer disposed on the second electrode; and a first drive device and a second drive device; When the first electrode is used as a negative electrode and the second electrode is used as a positive electrode, the first driving device is configured to input a lithium solution to be extracted into the first deintercalation tank, and the second driving device is configured to input a lithium-rich solution into the second deintercalation tank, and the volume of the lithium solution to be extracted entering the first deintercalation tank is greater than the volume of the lithium-rich solution entering the second deintercalation tank in the same unit time; When the first electrode is used as a positive electrode and the second electrode is used as a negative electrode, the first driving device is configured to input a lithium solution to be extracted into the second deintercalation tank, and the second driving device is configured to input a lithium-rich solution into the first deintercalation tank, and the volume of the lithium solution to be extracted entering the second deintercalation tank is greater than the volume of the lithium-rich solution entering the first deintercalation tank in the same unit time.

2. The electrochemical deintercalation lithium extraction system according to claim 1, characterized in that: When the first electrode is used as a negative electrode and the second electrode is used as a positive electrode, the first driving device is configured to input a lithium solution to be extracted into the first deintercalation tank, and the first driving device has a first output power; the second driving device is configured to input a lithium-rich solution into the second deintercalation tank, and the second driving device has a second output power; the second output power is less than the first output power; When the first electrode is used as a positive electrode and the second electrode is used as a negative electrode, the first driving device is configured to input a lithium solution to be extracted into the second deintercalation tank, and the first driving device has a third output power; the second driving device is configured to input a lithium-rich solution into the first deintercalation tank, and the second driving device has a fourth output power; the fourth output power is less than the third output power.

3. The electrochemical deintercalation lithium extraction system according to claim 2, characterized in that: The fourth output power is less than the first output power; and / or the second output power is less than the third output power.

4. The electrochemical deintercalation lithium extraction system according to claim 1, characterized in that: The lithium solution to be extracted includes lithium ions, and the concentration of the lithium ions in the lithium solution to be extracted is greater than or equal to 0.32 g / L and less than or equal to 1.2 g / L.

5. The electrochemical deintercalation lithium extraction system according to claim 1, characterized in that: When the first electrode is used as a negative electrode and the second electrode is used as a positive electrode, the first driving device is configured to input a lithium solution to be extracted into the first deintercalation tank, and the first driving device has a first frequency; the second driving device is configured to input a lithium-rich solution into the second deintercalation tank, and the second driving device has a second frequency; the second frequency is less than the first frequency.

6. The electrochemical deintercalation lithium extraction system according to claim 1, characterized in that: When the first electrode is used as a positive electrode and the second electrode is used as a negative electrode, the first driving device is configured to input a lithium solution to be extracted into the second deintercalation tank, and the first driving device has a third frequency; the second driving device is configured to input a lithium-rich solution into the first deintercalation tank, and the second driving device has a fourth frequency; the fourth frequency is less than the third frequency.

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