Device system for extracting lithium from salt lake brine

Abstract

The utility model provides a device system for extracting lithium from salt lake brine. The device system comprises an adsorption buffer device, a filter pressing unit, a microfiltration device, an ultrafiltration device, a nanofiltration device, a reverse osmosis concentration device, a calcium and magnesium removal device, a boron removal unit, a concentration device and a lithium precipitation device which are sequentially connected along the flowing direction of feed liquid, and an inlet of the adsorption buffer device is respectively connected with the coal ash feed liquid storage tank and the old brine tank. The device system provided by the utility model can be used for effectively separating impurities in salt lake brine, effectively reducing the blocking risk of a subsequent membrane assembly and improving the operation stability and the lithium extraction effect.

Description

Technical Field

[0001] This utility model relates to the field of salt lake brine resource recovery technology, specifically to a device system for lithium extraction from salt lake brine. Background Technology

[0002] With the development of electric vehicles and energy storage, the demand for lithium carbonate is increasing. Currently, lithium carbonate mining mainly includes lithium extraction from lepidolite, lithium extraction from spodumene, and lithium extraction from salt lakes. Among these, the cost of lithium extraction from salt lakes is much lower than that from lepidolite and spodumene. In particular, with the continuous advancement of salt lake lithium extraction technology and the decline in lithium carbonate prices, the market share of salt lake lithium extraction is gradually increasing.

[0003] Currently, lithium extraction from salt lakes in China is mainly concentrated in Qinghai and Tibet, including Qarhan Salt Lake, East and West Taijinaier Salt Lake, Yiliping Salt Lake, and Zabuye Chaka Salt Lake. Due to factors such as concentration, there is currently no technology for direct lithium extraction from salt lake brine. The main methods used are adsorption and membrane processes to extract lithium from the old brine produced after potassium precipitation.

[0004] However, the suspended solids and organic matter in the old brine produced after potassium precipitation will increase the viscosity of the brine, which will have an adverse effect on the subsequent separation steps. The main effects include: (1) Nanofiltration membranes and reverse osmosis membranes are commonly used separation technologies in the lithium extraction process of salt lake brine. However, when the brine viscosity increases, the membrane pores are easily blocked by suspended solids and organic matter, resulting in a decrease in membrane flux and a reduction in separation efficiency; (2) Adsorbents are mainly used to further remove impurities such as organic matter and metals in the lithium extraction process. When the content of suspended solids and organic matter in the brine is too high, it will cause the pores of the adsorbent to be blocked, reducing the adsorption efficiency and capacity of the adsorbent. In addition, the blockage of the adsorbent will also cause the adsorbent to be poisoned, making it unable to effectively remove impurities in the brine, thus seriously affecting the separation effect of the overall process; (3) The increase in brine viscosity, membrane blockage and adsorbent blockage will lead to a decrease in the stability of the lithium extraction process, which will not only reduce the product quality, but may also affect the continuous operation of the production line and increase production costs.

[0005] Therefore, providing a stable operating device system for lithium extraction from salt lake water is a technical problem that needs to be solved in this field. Utility Model Content

[0006] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a device system for lithium extraction from salt lake brine. The device system can effectively separate impurities in salt lake brine, effectively reduce the risk of blockage of subsequent membrane modules, and improve the stability of operation and lithium extraction effect.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] This utility model provides a device system for lithium extraction from salt lake brine. The device system includes an adsorption buffer device, a pressure filter unit, a microfiltration device, an ultrafiltration device, a nanofiltration device, a reverse osmosis concentration device, a calcium and magnesium removal device, a boron removal unit, a concentration device, and a lithium precipitation device, which are connected in sequence along the flow direction of the liquid.

[0009] The inlet of the adsorption buffer device is connected to the fly ash liquid storage tank and the old brine tank, respectively.

[0010] The device system provided by this utility model includes an adsorption buffer device that provides an adsorption buffer for adsorbents such as fly ash, initially adsorbing dissolved organic matter, heavy metal ions, and other impurities in salt lake brine; a pressure filtration unit for separating the feed liquid and removing sludge; a microfiltration device for effectively removing large particulate impurities and suspended solids from the brine; an ultrafiltration device for removing smaller particles and colloids; and a nanofiltration device for further deep impurity removal. The feed liquid treated by the nanofiltration device is then deeply concentrated by a reverse osmosis concentration device to increase the lithium ion concentration. A calcium and magnesium removal device and a boron removal unit are used to specifically remove calcium, magnesium, and boron impurities from the feed liquid, avoiding any impact on the quality of the lithium product. A concentration device further concentrates the feed liquid, increasing the lithium ion concentration and providing more suitable conditions for the subsequent lithium precipitation process, reducing reagent usage and processing costs. Finally, a lithium precipitation device is used to add a lithium precipitation agent to the concentrated feed liquid to achieve lithium extraction and recovery.

[0011] Preferably, the filter press unit includes a primary plate and frame filter press and a secondary plate and frame filter press connected in sequence.

[0012] Preferably, the filter press unit further includes a sampling inspection tank and a non-conforming liquid tank; the filtrate outlet of the primary plate and frame filter press is connected to the inlet of the sampling inspection tank; the non-conforming liquid outlet of the sampling inspection tank is connected to the inlet of the non-conforming liquid tank; the conforming liquid outlet of the sampling inspection tank is connected to the inlet of the secondary plate and frame filter press; and the outlet of the non-conforming liquid tank is connected to the inlet of the adsorption buffer device.

[0013] In this invention, a sampling inspection tank and a non-conforming liquid tank are installed. The sampling inspection tank is located between the primary plate and frame filter press and the secondary plate and frame filter press. The sampling inspection tank can perform real-time sampling inspection of the filtrate from the primary plate and frame filter press to ensure that the quality of the filtrate meets the requirements of subsequent processing processes, thereby guaranteeing the overall processing effect of the system and the quality of the final product. The non-conforming liquid tank is used to collect the non-conforming filtrate from the sampling inspection and return it to the adsorption buffer device. This circulation mechanism reduces the waste of reagents and the increase in processing costs in subsequent processes, further improving the stability and economic benefits of the system.

[0014] Preferably, the filter press unit further includes a secondary brine buffer tank and a secondary brine filtrate tank connected in sequence; the filtrate outlet of the secondary plate and frame filter press is connected to the inlet of the secondary brine buffer tank; and the outlet of the secondary brine filtrate tank is connected to the inlet of the microfiltration device.

[0015] In this invention, by setting up a two-stage brine buffer tank, the filtrate discharged from the plate and frame filter press can be buffered, making the flow of the filtrate more stable, reducing flow fluctuations, and providing stable liquid inlet conditions for subsequent devices.

[0016] Preferably, the microfiltration device includes a microfiltration membrane module; the outlet of the pressure filter unit and the outlet of the dilution water pipeline are respectively connected to the inlet of the microfiltration membrane module; the outlet of the microfiltration membrane module is connected to the inlet of the ultrafiltration device.

[0017] Preferably, the ultrafiltration device includes an ultrafiltration membrane module; the outlet of the microfiltration device and the outlet of the dilution water pipeline are respectively connected to the inlet of the ultrafiltration membrane module; the outlet of the ultrafiltration membrane module is connected to the inlet of the nanofiltration device.

[0018] Preferably, the concentrate outlet of the reverse osmosis concentration unit is connected to the inlet of the calcium and magnesium removal unit.

[0019] Preferably, the calcium and magnesium removal device includes a calcium and magnesium removal resin assembly; the concentrate outlet of the reverse osmosis concentration device is connected to the inlet of the calcium and magnesium removal resin assembly; and the outlet of the calcium and magnesium removal resin assembly is connected to the inlet of the boron removal unit.

[0020] In this invention, the preferred method of using ion exchange resin to remove calcium and magnesium facilitates the efficient removal of calcium and magnesium impurities.

[0021] Preferably, the boron removal unit includes a first boron removal device and a second boron removal device connected in sequence; the first boron removal device includes a nanofiltration membrane assembly; the second boron removal device includes a boron removal resin assembly; the outlet of the calcium and magnesium removal device is connected to the inlet of the nanofiltration membrane assembly; the outlet of the nanofiltration membrane assembly is connected to the inlet of the boron removal resin assembly; and the outlet of the boron removal resin assembly is connected to the inlet of the concentration device.

[0022] In this invention, by setting up a boron removal unit and using a combination of nanofiltration and ion exchange resin for boron removal, most of the boron is first removed by nanofiltration membrane, and then the remaining small amount of boron is removed by ion exchange resin. This can improve boron removal efficiency, reduce processing costs, and maintain system stability.

[0023] Preferably, the concentration device includes an MVR concentration device; the outlet of the MVR concentration device is connected to the inlet of the lithium precipitation device.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) In the device system provided by this utility model, by combining the adsorption buffer process and the combined pressure filtration process, fly ash is used to initially adsorb dissolved organic matter, heavy metal ions and other impurities in the salt lake brine, and the combined pressure filtration of the first-stage plate and frame filter press and the second-stage plate and frame filter press effectively achieves the initial adsorption and separation of impurities, improves the safety and stability of the device system, and lays the foundation for subsequent processing steps.

[0026] (2) In the device system provided by this utility model, the combination of microfiltration, ultrafiltration and nanofiltration processes can effectively remove large particulate impurities and suspended solids in the brine, while ultrafiltration can further remove smaller particles and colloids, avoiding interference with subsequent nanofiltration and reverse osmosis concentration, effectively reducing the risk of blockage of subsequent membrane modules, extending the service life of the membrane, and improving the stability of operation and lithium extraction effect.

[0027] (3) The device system provided by this utility model can significantly improve the purity of the final product and meet the production requirements of high-quality products through multi-stage filtration and separation, as well as the specific removal of impurities such as calcium, magnesium, and boron. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the device system provided in Embodiment 1 of this utility model;

[0029] In the diagram: 1-Fly ash liquid storage tank; 2-Old brine tank; 3-Adsorption buffer device; 4-First-stage plate and frame filter press; 5-Sampling inspection tank; 6-Unqualified liquid tank; 7-Second-stage plate and frame filter press; 8-Second-stage old brine buffer tank; 9-Second-stage old brine filtrate tank; 10-Microfiltration device; 11-Ultrafiltration device; 12-Nanofiltration device; 13-Reverse osmosis concentration device; 14-Calcium and magnesium removal device; 15-First boron removal device; 16-Second boron removal device; 17-Concentration device; 18-Lithium precipitation device. Detailed Implementation

[0030] It should be understood that in the description of this utility model, the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0031] It should be noted that, in the description of this utility model, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0033] In one specific implementation, such as Figure 1 As shown, this utility model provides a device system for lithium extraction from salt lake brine. The device system includes an adsorption buffer device 3, a pressure filtration unit, a microfiltration device 10, an ultrafiltration device 11, a nanofiltration device 12, a reverse osmosis concentration device 13, a calcium and magnesium removal device 14, a boron removal unit, a concentration device 17, and a lithium precipitation device 18, which are connected in sequence along the flow direction of the liquid. The inlet of the adsorption buffer device 3 is connected to the fly ash liquid storage tank 1 and the old brine tank 2, respectively.

[0034] The device system provided by this invention can effectively separate impurities in salt lake brine, effectively reduce the risk of blockage of subsequent membrane modules, and improve operational stability and lithium extraction efficiency.

[0035] Furthermore, the filter press unit includes a primary plate and frame filter press 4 and a secondary plate and frame filter press 7 connected in sequence.

[0036] Furthermore, the filter press unit also includes a sampling inspection tank 5 and a non-conforming liquid tank 6; the filtrate outlet of the primary plate and frame filter press 4 is connected to the inlet of the sampling inspection tank 5; the non-conforming liquid outlet of the sampling inspection tank 5 is connected to the inlet of the non-conforming liquid tank 6; the conforming liquid outlet of the sampling inspection tank 5 is connected to the inlet of the secondary plate and frame filter press 7; and the outlet of the non-conforming liquid tank 6 is connected to the inlet of the adsorption buffer device 3.

[0037] In this invention, a sampling inspection tank 5 and a non-conforming liquid tank 6 are provided. The sampling inspection tank 5 is located between the primary plate and frame filter press 4 and the secondary plate and frame filter press 7. The sampling inspection tank 5 can perform real-time sampling inspection of the filtrate from the primary plate and frame filter press 4 to ensure that the quality of the filtrate meets the requirements of subsequent processing processes, thereby guaranteeing the overall processing effect of the system and the quality of the final product. The non-conforming liquid tank 6 is used to collect the non-conforming filtrate from the sampling inspection and return it to the adsorption buffer device 3. This circulation mechanism reduces the waste of reagents and the increase in processing costs in subsequent processes, further improving the stability and economic benefits of the system.

[0038] Furthermore, the filter press unit also includes a secondary brine buffer tank 8 and a secondary brine filtrate tank 9 connected in sequence; the filtrate outlet of the secondary plate and frame filter press 7 is connected to the inlet of the secondary brine buffer tank 8; and the outlet of the secondary brine filtrate tank 9 is connected to the inlet of the microfiltration device 10.

[0039] In this invention, by setting a secondary brine buffer tank 8, the filtrate discharged from the plate and frame filter press can be buffered, making the flow of the filtrate more stable, reducing flow fluctuations, and providing stable liquid inlet conditions for subsequent devices.

[0040] Furthermore, the microfiltration device 10 includes a microfiltration membrane module; the outlet of the pressure filter unit and the outlet of the dilution water pipeline are respectively connected to the inlet of the microfiltration membrane module; the outlet of the microfiltration membrane module is connected to the inlet of the ultrafiltration device 11.

[0041] Furthermore, the ultrafiltration device 11 includes an ultrafiltration membrane module; the outlet of the microfiltration device 10 and the outlet of the dilution water pipeline are respectively connected to the inlet of the ultrafiltration membrane module; the outlet of the ultrafiltration membrane module is connected to the inlet of the nanofiltration device 12.

[0042] Furthermore, the concentrate outlet of the reverse osmosis concentration unit 13 is connected to the inlet of the calcium and magnesium removal unit 14.

[0043] Furthermore, the calcium and magnesium removal device 14 includes a calcium and magnesium removal resin assembly; the concentrate outlet of the reverse osmosis concentration device 13 is connected to the inlet of the calcium and magnesium removal resin assembly; and the outlet of the calcium and magnesium removal resin assembly is connected to the inlet of the boron removal unit.

[0044] In this invention, the preferred method of using ion exchange resin to remove calcium and magnesium facilitates the efficient removal of calcium and magnesium impurities.

[0045] Further, the boron removal unit includes a first boron removal device 15 and a second boron removal device 16 connected in sequence; the first boron removal device 15 includes a nanofiltration membrane assembly; the second boron removal device 16 includes a boron removal resin assembly; the outlet of the calcium and magnesium removal device 14 is connected to the inlet of the nanofiltration membrane assembly; the outlet of the nanofiltration membrane assembly is connected to the inlet of the boron removal resin assembly; and the outlet of the boron removal resin assembly is connected to the inlet of the concentration device 17.

[0046] In this invention, by setting up a boron removal unit and using a combination of nanofiltration and ion exchange resin for boron removal, most of the boron is first removed by nanofiltration membrane, and then the remaining small amount of boron is removed by ion exchange resin. This can improve boron removal efficiency, reduce processing costs, and maintain system stability.

[0047] Furthermore, the concentration device 17 includes an MVR concentration device; the outlet of the MVR concentration device is connected to the inlet of the lithium precipitation device 18.

[0048] Example 1

[0049] This embodiment provides a device system for lithium extraction from salt lake brine, such as... Figure 1 As shown, the device system includes an adsorption buffer device 3, a filter press unit, a microfiltration device 10, an ultrafiltration device 11, a nanofiltration device 12, a reverse osmosis concentration device 13, a calcium and magnesium removal device 14, a boron removal unit, a concentration device 17, and a lithium precipitation device 18 connected in sequence along the direction of liquid flow; the filter press unit includes a primary plate and frame filter press 4, a secondary plate and frame filter press 7, a sampling inspection tank 5, a non-conforming liquid tank 6, a secondary old brine buffer tank 8, and a secondary old brine filtrate tank 9 connected in sequence.

[0050] The inlet of the adsorption buffer device 3 is connected to the fly ash liquid storage tank 1 and the old brine tank 2 respectively. The outlet of the adsorption buffer device 3 is connected to the first-stage plate and frame filter press 4. The filtrate outlet of the first-stage plate and frame filter press 4 is connected to the inlet of the sampling inspection tank 5. The unqualified liquid outlet of the sampling inspection tank 5 is connected to the inlet of the unqualified liquid tank 6. The qualified liquid outlet of the sampling inspection tank 5 is connected to the inlet of the second-stage plate and frame filter press 7. The outlet of the unqualified liquid tank 6 is connected to the inlet of the adsorption buffer device 3. The filtrate outlet of the second-stage plate and frame filter press 7 is connected to the inlet of the second-stage old brine buffer tank 8. The outlet of the second-stage old brine buffer tank 8 is connected to the second-stage old brine filtrate tank 9. The outlet of the second-stage old brine filtrate tank 9 is connected to the inlet of the microfiltration device 10. The sludge produced by the first-stage plate and frame filter press 4 and the second-stage plate and frame filter press 7 is sent externally.

[0051] The microfiltration device 10 includes a microfiltration membrane module. The outlet of the secondary brine filtrate tank 9 and the outlet of the dilution water pipeline are respectively connected to the inlet of the microfiltration membrane module. The outlet of the microfiltration membrane module is connected to the inlet of the ultrafiltration device 11.

[0052] The ultrafiltration device 11 includes an ultrafiltration membrane module. The outlet of the microfiltration membrane module and the outlet of the dilution water pipeline are respectively connected to the inlet of the ultrafiltration membrane module. The outlet of the ultrafiltration membrane module is connected to the inlet of the nanofiltration device 12. The outlet of the nanofiltration device 12 is connected to the reverse osmosis concentration device 13.

[0053] The calcium and magnesium removal device 14 includes a calcium and magnesium removal resin assembly. The concentrated liquid outlet of the reverse osmosis concentration device 13 is connected to the inlet of the calcium and magnesium removal resin assembly, and the outlet of the calcium and magnesium removal resin assembly is connected to the inlet of the boron removal unit.

[0054] The boron removal unit includes a first boron removal device 15 and a second boron removal device 16 connected in sequence. The first boron removal device 15 includes a nanofiltration membrane assembly, and the second boron removal device 16 includes a boron removal resin assembly. The outlet of the calcium and magnesium removal resin assembly is connected to the inlet of the nanofiltration membrane assembly, the outlet of the nanofiltration membrane assembly is connected to the inlet of the boron removal resin assembly, and the outlet of the boron removal resin assembly is connected to the inlet of the concentration device 17.

[0055] The concentration device 17 includes an MVR concentration device, the outlet of which is connected to the inlet of the lithium precipitation device 18.

[0056] The operating process of the device system provided in this embodiment for lithium extraction from salt lake brine is as follows:

[0057] The brine from the salt lake is stored in the old brine tank 2. Fly ash and water are added to the fly ash liquid storage tank 1 to prepare an adsorbent solution. The adsorbent solution and brine are then added to the adsorption buffer device 3 to adsorb dissolved organic matter, heavy metal ions, and other impurities in the brine. The adsorbed liquid is then sent to the primary plate and frame filter press 4 for solid-liquid separation. The resulting sludge is discharged. The resulting filtrate is sent to the sampling and testing tank 5 for testing. If the filtrate is qualified, it is sent to the secondary plate and frame filter press 7 for solid-liquid separation. If the filtrate is unqualified, it is sent to the unqualified liquid tank 6 and then returned to the adsorption buffer device 3. After solid-liquid separation in the secondary plate and frame filter press 7, the resulting filtrate first enters the secondary old brine buffer tank 8 and then is sent to the secondary old brine filtrate tank 9 for storage. The resulting sludge is discharged.

[0058] The filtrate in the secondary brine filtrate tank 9 is sequentially passed through a microfiltration device 10, an ultrafiltration device 11, and a nanofiltration device 12 for impurity removal. Diluent is added to the microfiltration device 10 and the ultrafiltration device 11. The filtrate after nanofiltration is concentrated by a reverse osmosis concentration device 13. Then, calcium and magnesium impurities are removed by the calcium and magnesium removal resin component in the calcium and magnesium removal device 14. Most of the boron is removed by the nanofiltration membrane component in the first boron removal device 15. Then, a small amount of remaining boron is removed by the boron removal resin component in the second boron removal device 16. Finally, the filtrate enters the concentration device 17 for concentration. The resulting concentrate is treated with a lithium precipitation agent in the lithium precipitation device 18 to obtain lithium carbonate.

[0059] In summary, the device system provided by this utility model can effectively separate impurities in salt lake brine, effectively reduce the risk of subsequent membrane module clogging, and improve operational stability and lithium extraction efficiency.

[0060] The applicant declares that the above description is only a specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model fall within the protection and disclosure scope of the present utility model.

Claims

1. A device system for lithium extraction from salt lake brine, characterized in that, The device system includes an adsorption buffer device, a pressure filtration unit, a microfiltration device, an ultrafiltration device, a nanofiltration device, a reverse osmosis concentration device, a calcium and magnesium removal device, a boron removal unit, a concentration device, and a lithium precipitation device, which are connected in sequence along the direction of liquid flow. The inlet of the adsorption buffer device is connected to the fly ash liquid storage tank and the old brine tank, respectively.

2. The apparatus system for lithium extraction from salt lake brine according to claim 1, characterized in that, The filter press unit includes a primary plate and frame filter press and a secondary plate and frame filter press connected in sequence.

3. The apparatus system for lithium extraction from salt lake brine according to claim 2, characterized in that, The filter press unit also includes a sampling inspection tank and a non-conforming liquid tank; The filtrate outlet of the primary plate and frame filter press is connected to the inlet of the sampling and testing tank; The outlet of the non-conforming liquid in the sampling inspection tank is connected to the inlet of the non-conforming liquid tank. The outlet of the qualified liquid from the sampling inspection tank is connected to the inlet of the secondary plate and frame filter press; The outlet of the substandard liquid tank is connected to the inlet of the adsorption buffer device.

4. The apparatus system for lithium extraction from salt lake brine according to claim 2, characterized in that, The filter press unit also includes a secondary brine buffer tank and a secondary brine filtrate tank connected in sequence; The filtrate outlet of the secondary plate and frame filter press is connected to the inlet of the secondary brine buffer tank; The outlet of the secondary brine filtrate tank is connected to the inlet of the microfiltration device.

5. The apparatus system for lithium extraction from salt lake brine according to claim 1, characterized in that, The microfiltration device includes a microfiltration membrane assembly; The outlet of the filter press unit and the outlet of the dilution water pipeline are respectively connected to the inlet of the microfiltration membrane module; The outlet of the microfiltration membrane module is connected to the inlet of the ultrafiltration device.

6. The apparatus system for lithium extraction from salt lake brine according to claim 1, characterized in that, The ultrafiltration device includes an ultrafiltration membrane module; The outlet of the microfiltration device and the outlet of the dilution water pipeline are respectively connected to the inlet of the ultrafiltration membrane module; The outlet of the ultrafiltration membrane module is connected to the inlet of the nanofiltration unit.

7. The apparatus system for lithium extraction from salt lake brine according to claim 1, characterized in that, The outlet of the reverse osmosis concentration unit is connected to the inlet of the calcium and magnesium removal unit.

8. The apparatus system for lithium extraction from salt lake brine according to claim 7, characterized in that, The calcium and magnesium removal device includes a calcium and magnesium removal resin assembly. The concentrated liquid outlet of the reverse osmosis concentration unit is connected to the inlet of the calcium and magnesium removal resin component. The outlet of the calcium and magnesium resin removal component is connected to the inlet of the boron removal unit.

9. The apparatus system for lithium extraction from salt lake brine according to claim 1, characterized in that, The boron removal unit includes a first boron removal device and a second boron removal device connected in sequence. The first boron removal device includes a nanofiltration membrane assembly; The second boron removal device includes a boron removal resin assembly; The outlet of the calcium and magnesium removal device is connected to the inlet of the nanofiltration membrane module; The outlet of the nanofiltration membrane module is connected to the inlet of the boron removal resin module; The outlet of the boron removal resin assembly is connected to the inlet of the concentration device.

10. The apparatus system for lithium extraction from salt lake brine according to claim 1, characterized in that, The concentration device includes an MVR concentration device; The outlet of the MVR concentration unit is connected to the inlet of the lithium precipitation unit.

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