Continuous ion exchange system for improving lithium extraction effect of salt lake at variable speed and variable pressure

Abstract

The utility model provides a continuous ion exchange system capable of improving the lithium extraction effect of a salt lake at variable speed and variable pressure, which belongs to the technical field of salt lake lithium extraction equipment and comprises an adsorption area, a leaching impurity removal area, an elution area and a leaching material ejection area, and the operation steps of the system are adsorption, leaching impurity removal, elution and leaching material ejection in sequence; the adsorption area comprises a plurality of adsorption towers and is provided with a feed storage tank; the adsorption area is divided into two sections for feeding, feeding liquid of the first-section adsorption tower is connected in parallel and fed at the same time, and every two strands of discharging liquid are combined into one strand to enter the second-section adsorption tower; discharging liquid of the second-section adsorption tower enters a tail liquid tank to be collected or discharged. According to the utility model, according to the use states of the adsorbent in different time periods, a multi-tower parallel connection and unification connection mode is adopted to realize variable speed and variable pressure and reasonably distribute the structure-function relationship between the adsorbent and the fed material, so that the adsorption yield is improved, the adsorption effect is enhanced, the leaching efficiency is improved, the water consumption is reduced, and the production cost is reduced.

Description

Technical Field

[0001] This utility model relates to the technical field of lithium extraction equipment from salt lakes, specifically to a continuous ion-exchange system for improving the lithium extraction effect from salt lakes by changing speed and pressure. Background Technology

[0002] Salt lakes contain abundant metal resources, such as lithium, potassium, sodium, and magnesium. Effective extraction is a key focus, with lithium extraction from salt lakes being a research hotspot due to its strategic importance in new energy sources. Common methods for lithium extraction include solarization, adsorption, extraction, and electro-deintercalation / extraction. In recent years, adsorption lithium extraction technology has seen rapid development due to its advantages of high efficiency, cleanliness, and low pollution, especially the industrial application of aluminum-based adsorbents and titanium-based lithium-ion sieve materials. The main mechanism of lithium-ion sieve extraction involves ion exchange between lithium ions in the salt lake brine and occupier ions at specific pore sites on a lithium-ion sieve. The lithium ions are then eluted, and this process is repeated. Currently, the adsorption stage in adsorption lithium extraction uses a single series-parallel connection, resulting in a uniform flow rate. This lack of differentiation in flow rates between stages prevents effective utilization of the adsorbent, leading to low overall adsorbent utilization. Increasing pressure can only be achieved by simply increasing the flow rate, but this increases the overall system operating pressure and the equipment's operating load.

[0003] Chinese invention patent CN102031368A discloses a continuous ion exchange device for extracting lithium from salt lake brine. The adsorption resin column group adopts a three-column series adsorption, and the lithium adsorption yield can only be controlled by a single feed flow rate. Faced with multiple columns in parallel, the adsorption of a single feed flow rate cannot fully utilize the performance of the adsorbent in the adsorption column. Utility Model Content

[0004] The purpose of this invention is to provide a continuous cross-linking system for improving lithium extraction from salt lakes by varying speed and pressure, so as to solve at least one of the technical problems existing in the background art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This utility model provides a continuous ion-exchange system for improving the adsorption and lithium extraction effect in salt lakes by varying speed and pressure, comprising:

[0007] In a continuous ion exchange device, the adsorption column is filled with one or more of aluminum-based adsorbents, titanium-based adsorbents, and manganese-based adsorbents; the continuous ion exchange system is divided into different functional zones, namely an adsorption zone, a rinsing and impurity removal zone, an elution zone, and a rinsing and top material zone, and the system operation sequence is adsorption-rinsing and impurity removal-elution-rinsing and top material.

[0008] The continuous ion exchange device includes twenty or thirty adsorption towers, and the operating direction is from the thirtieth or twentieth adsorption tower to the first adsorption tower.

[0009] The adsorption zone is divided into nine to eighteen adsorption towers, each equipped with a feed storage tank. The feed liquid of the first-stage adsorption tower is fed in parallel simultaneously, and the feeding method can be from top to bottom or from bottom to top. Every two streams of effluent are combined into one stream and enter the second-stage adsorption tower, and the feeding method can be from top to bottom or from bottom to top. The effluent from the second-stage adsorption tower is collected in a tail liquid tank or discharged externally. The first to tenth adsorption towers are fed into the first-stage adsorption towers respectively. The effluent from the first and second adsorption towers are mixed into one stream and enter the eleventh adsorption tower. The effluent from the third and fourth adsorption towers are mixed into one stream and enter the twelfth adsorption tower. The effluent from the fifth and sixth adsorption towers are mixed into one stream and enter the thirteenth adsorption tower. The effluent from the seventh and eighth adsorption towers are mixed into one stream and enter the fourteenth adsorption tower. The effluent from the ninth and tenth adsorption towers are mixed into one stream and enter the fifteenth adsorption tower. The effluent from the eleventh to fifteenth adsorption towers is discharged into the adsorption tail liquid storage tank or discharged externally.

[0010] The rinsing and impurity removal zone is equipped with two to four adsorption towers, divided into fast rinsing and slow rinsing. The rinsing and impurity removal solution is low-calcium magnesium water or pure water stored in the rinsing and impurity removal tank. The adsorption towers are connected in series, parallel, or multiple towers connected in parallel and unified. When equipped with four adsorption towers, the first and second adsorption towers are fed in parallel to implement the slow rinsing sequence. The effluents are mixed together and enter the third adsorption tower. The effluent from the third adsorption tower enters the fourth adsorption tower to implement the fast rinsing sequence. When equipped with three adsorption towers, the first and second adsorption towers are fed in parallel to implement the slow rinsing sequence. The effluents are mixed together and enter the third adsorption tower to implement the fast rinsing sequence.

[0011] The elution zone is equipped with four to ten adsorption towers, each with a qualified elution liquid tank. The elution liquid is pure water or low-concentration acid. The adsorption towers are connected in parallel or in series.

[0012] The elution zone is divided into a first-stage, second-stage, third-stage, or fourth-stage elution section, and the first, second, third, or fourth qualified elution solution is obtained and enters the first, second, third, or fourth qualified elution solution storage tank. The feed liquid for the fourth-stage elution section is the water stored in the elution water tank. The qualified elution solution for the third stage is the feed liquid for the third-stage elution section. The qualified elution solution for the second stage is the feed liquid for the second-stage elution section. The qualified elution solution for the first stage is the feed liquid for the first-stage elution section.

[0013] The top washing area is equipped with one to four adsorption towers, each with a washing liquid storage tank. The top washing liquid is pure water, adsorption tail liquid, or air. The adsorption towers are connected in series or in parallel.

[0014] The feed liquid for the adsorption tower includes, but is not limited to, raw brine from salt lakes, old brine, lithium-containing water from oil and gas fields, and lithium precipitation mother liquor.

[0015] Furthermore, an online conductivity or pH monitoring device is installed at the outlet of the first adsorption tower entering the adsorption zone, and the low conductivity or low pH outlet liquid is discharged into a low calcium and magnesium water storage tank or a washing water tank.

[0016] Furthermore, an online conductivity or pH monitoring device is installed at the outlet of the first adsorption tower in the elution zone. Low conductivity or high pH outlet liquid is discharged into a low calcium and magnesium water storage tank or an elution water tank.

[0017] Furthermore, the outlet of the first-stage qualified eluent is equipped with pH and / or conductivity online monitoring equipment. Low conductivity and high pH discharge liquid is discharged into a low calcium and magnesium water storage tank or an eluent water tank, while high conductivity and low pH discharge liquid is discharged into a qualified liquid storage tank.

[0018] Furthermore, the qualified eluent storage tanks at each elution stage are connected by qualified eluent transfer pumps;

[0019] The top feed liquid in the rinsing top feed zone enters the adsorption tower from bottom to top. An online conductivity monitoring device is installed at the outlet of the discharge liquid. If the conductivity is lower than the set conductivity, it is discharged into the washing and dewatering tank. If the conductivity is higher than the set conductivity, it is discharged into the tail liquid tank.

[0020] The feed inlets of all adsorption towers in the adsorption zone, the first adsorption tower in the rinsing and impurity removal zone, all adsorption towers in the elution zone, and the first adsorption tower in the rinsing and top material removal zone are equipped with pressure and flow monitoring devices.

[0021] The beneficial effects of this invention are as follows: Based on the adsorbent's usage status at different times, a multi-tower parallel-to-unified connection method is adopted to achieve variable speed and pressure, rationally allocating the structure-activity relationship between the adsorbent and the feed, improving adsorption yield, enhancing adsorption effect, increasing rinsing efficiency, reducing water consumption, and facilitating production cost control. In the continuous ion exchange system, a segmented multi-parallel-to-unified process is adopted. The first-stage adsorption involves multiple columns in parallel feeding and low-pressure operation; the second-stage adsorption feed is the same as the first-stage adsorption output, with the feed rate being the total mixed amount of the output from two or more adsorption columns in the first stage, thereby increasing the feed rate of the second-stage adsorption, increasing the operating pressure, and strengthening the adsorption process. The flow rate of the second-stage adsorption can be adjusted by the individual columns in the first stage, achieving separate control. Through the multi-tower parallel-to-series connection method, the adsorption process achieves rapid pressurized adsorption and slow low-pressure adsorption, and the rinsing process achieves automatic allocation of fast and slow rinsing.

[0022] This invention, based on the varying saturation state, operating flow rate, and pressure of the adsorbent within the adsorption column of a continuous ion exchange system, optimizes the process to achieve variable-speed adsorption while simultaneously adjusting pressure changes. This promotes the adsorption process, controls the utilization rate of the adsorbent within the column, and employs a multi-parallel-to-one process. Specifically, a first-stage adsorption is followed by a second-stage adsorption. The first-stage adsorption involves multiple columns fed in parallel, while the second-stage adsorption involves the material from the first-stage parallel adsorption being integrated into a single stream. This achieves slow, low-pressure adsorption in the first stage and rapid, high-pressure adsorption in the second stage, simultaneously regulating both speed and pressure, thus improving the adsorption effect. Furthermore, the rinsing process utilizes a multi-column parallel-to-unified configuration to automatically allocate fast and slow rinsing, as well as atmospheric and low-pressure settings, further enhancing the rinsing effect.

[0023] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of the invention. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a flow chart of the continuous ion-exchange system for improving lithium extraction from salt lakes using variable speed and pressure as described in Embodiment 1 of this utility model.

[0026] Figure 2 This is a flow chart of the continuous ion-exchange system for improving lithium extraction from salt lakes using variable speed and pressure as described in Embodiment 2 of this utility model.

[0027] Among them: 1-rinsing and impurity removal tank; 2-raw brine storage tank; 3-adsorption tail liquid tank; 4-elution water tank; 5-second-stage qualified elution liquid tank; 6-first-stage qualified elution liquid tank; 7-qualified liquid tank; 8-concentrated acid tank. Detailed Implementation

[0028] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0029] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0030] It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as here.

[0031] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the word “comprising” as used in this specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, and / or groups thereof.

[0032] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. Furthermore, the described specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0033] In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0034] In the description of this specification, the terms “center,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this technology 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 technology.

[0035] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting. Those skilled in the art can understand the specific meaning of these terms in this art according to the specific circumstances.

[0036] To facilitate understanding of this utility model, the present utility model will be further explained and described below with reference to the accompanying drawings and specific embodiments. The specific embodiments do not constitute a limitation on the embodiments of this utility model.

[0037] Those skilled in the art should understand that the accompanying drawings are merely schematic diagrams of embodiments, and the components in the drawings are not necessarily essential for implementing this utility model.

[0038] This invention provides a continuous ion exchange system for improving lithium extraction from salt lakes through variable speed and pressure. It aims to solve the problems of poor adsorption efficiency, low adsorption yield, and uneven distribution of adsorbent performance in the uniform-rate adsorption process within a continuous ion exchange system during lithium extraction from salt lakes. Uniform-rate adsorption maintains a single flow rate through the adsorption device at a constant pressure, resulting in poor adsorption efficiency and uneven saturation of the adsorbent at the beginning and end of the adsorption column. Specifically, the adsorbent entering the adsorption process earlier reaches saturation first, while the adsorbent entering later still retains some adsorption capacity, leading to uneven distribution of adsorbent performance. This invention addresses this issue by using a multi-stage, unified connection method. The first-stage brine feed fully utilizes its concentration advantage to enhance adsorption, while the second-stage feed leverages the pressure effect to promote mass transfer.

[0039] Example 1

[0040] In this embodiment 1, a continuous ion-exchange system process for improving lithium extraction efficiency through variable speed and pressure is provided. The continuous ion-exchange device is equipped with 30 adsorption towers, connected as follows: Figure 1 As shown in the diagram, the numbers 1 to 30 on the adsorption towers from left to right represent the tower numbers. Each adsorption tower is filled with titanium-based adsorbent. The 30 adsorption towers are divided into four functional zones: adsorption zone, rinsing and impurity removal zone, acid elution zone, and acid rinsing zone. Each tower is equipped with a rinsing and impurity removal tank 1, a raw brine storage tank 2, an adsorption tail liquid tank 3, an eluent tank 4, a second-stage qualified eluent tank 5, a first-stage qualified eluent tank 6, a qualified liquid tank 7, and a concentrated acid tank 8.

[0041] The rinsing and impurity removal area is equipped with four adsorption towers and a rinsing and impurity removal tank 1, numbered from No. 1 to No. 4 in sequence. The No. 1 and No. 2 adsorption towers are connected in parallel, and the No. 3 and No. 4 adsorption towers are connected in series. The feed is from top to bottom. The No. 1 and No. 2 adsorption towers are the slow washing step, and the No. 3 and No. 4 adsorption towers are the fast washing step. The effluent liquids are combined at the outlet and enter the No. 3 adsorption tower. The effluent liquid from the No. 3 adsorption tower then enters the No. 4 adsorption tower. The effluent liquid from the No. 4 adsorption tower is discharged to the original brine storage tank 1.

[0042] The adsorption section is divided into fifteen adsorption towers and a raw brine storage tank 2, numbered sequentially from the fifth to the nineteenth adsorption tower. Towers five, six, seven, eight, nine, ten, eleven, twelfth, thirteenth, and fourteenth are connected in parallel. Brine from the raw brine storage tank 2 is pumped from top to bottom into each parallel adsorption tower. The effluents from towers five and six are mixed and flow downwards into tower fifteen, and the effluents from towers seven and eight are mixed and flow downwards into tower sixteen. The effluents from adsorption towers 9 and 10 are mixed together and fed into adsorption tower 17 from top to bottom. The effluents from adsorption towers 11 and 12 are mixed together and fed into adsorption tower 18 from top to bottom. The effluents from adsorption towers 13 and 14 are mixed together and fed into adsorption tower 19 from bottom to top. The outlet of adsorption tower 19 is equipped with online conductivity and pH monitoring devices. The effluent with conductivity and pH values ​​lower than the set values ​​is discharged into washing water tank 4, and the effluent with conductivity higher than the set values ​​is discharged into tail liquid tank 3.

[0043] The acid rinsing section is equipped with three adsorption towers and an elution water tank, numbered 20 to 22. The three adsorption towers are connected in series. Pure water is pumped from the elution water tank 4 to the 20th adsorption tower for rinsing from top to bottom. The 20th adsorption tower is equipped with online conductivity and pH detection devices at the rinsing outlet to monitor the conductivity and pH at the rinsing outlet and to judge the rinsing effect. After the rinsing of the 22nd adsorption tower is completed, the effluent is discharged to the second-stage qualified elution liquid tank 5.

[0044] The acid elution zone is divided into eight adsorption towers, numbered 23 to 30, and is divided into two stages, with four adsorption towers forming one stage. Adsorption towers 23 to 26 form the second-stage elution zone, equipped with a second-stage qualified eluent tank 5. Adsorption towers 27 to 30 form the first-stage elution zone, equipped with a first-stage qualified eluent tank 6. The eluent enters the adsorption towers from top to bottom, and the qualified eluent returns to its respective qualified eluent tank. The effluent from adsorption tower 29 is the qualified eluent and is discharged to qualified eluent tank 7. The effluent outlet of adsorption tower 30 is equipped with pH and conductivity detection devices. If the conductivity is lower than the set value, the effluent is discharged to rinsing and impurity removal tank 1; if the conductivity is higher than the set value, it is discharged to the first-stage qualified eluent tank 6. A transfer pump is installed between the second-stage qualified eluent tank 5 and the first-stage qualified eluent tank 6 to transfer the qualified eluent from the second-stage qualified eluent tank 5 to the first-stage qualified eluent tank 6, balancing the liquid levels of the two qualified eluent tanks.

[0045] The second-stage qualified eluent tank 5 and the first-stage qualified eluent tank 6 are connected to the concentrated acid tank 8 via a feed pump. Both qualified eluent tanks are equipped with online pH monitoring devices. When the pH of the eluent is higher than the set pH, the concentrated acid feed pump is started to replenish the acid until the set pH is reached. When the pH of the eluent is lower than the set pH, the concentrated acid feed pump is stopped to stop replenishing the acid, and this cycle continues.

[0046] Example 2

[0047] This embodiment provides a continuous ion-exchange system process for improving lithium extraction efficiency through variable speed and voltage control. The continuous ion-exchange device is equipped with 30 adsorption towers, connected as follows: Figure 2 As shown, the adsorption tower is filled with aluminum-based adsorbent. The 30 adsorption towers are divided into four functional areas: adsorption area, rinsing and impurity removal area, elution area, and top material area. They are equipped with rinsing and impurity removal tank 1, raw brine storage tank 2, adsorption tail liquid tank 3, elution water tank 4, and elution qualified liquid tank 5.

[0048] The rinsing and impurity removal area is equipped with three adsorption towers and rinsing and impurity removal tank 1, numbered as No. 1 to No. 3 in sequence. The No. 1 and No. 2 adsorption towers are connected in parallel and are fed from top to bottom for rinsing. The No. 1 and No. 2 adsorption towers are slow washing steps. The effluent liquids merge into one stream at the outlet and enter the No. 3 adsorption tower. The No. 3 adsorption tower is fast washing step. The effluent liquids are discharged to the original brine storage tank 2.

[0049] The adsorption section is divided into eighteen adsorption towers and a raw brine storage tank 2, numbered sequentially from the fourth to the twenty-first adsorption tower. Towers four, five, six, seven, eight, nine, ten, eleven, twelfth, thirteenth, fourteenth, and fifteen are connected in parallel. Brine from the raw brine storage tank 2 is pumped from top to bottom into each parallel adsorption tower. The effluents from towers four and five are mixed and fed downwards into tower sixteen. The effluents from towers six and seven are mixed and fed upwards into tower sixteen. The liquid flows from the bottom into the 17th adsorption tower. The liquid from the 8th and 9th adsorption towers is mixed and flows from top to bottom into the 18th adsorption tower. The liquid from the 10th and 11th adsorption towers is mixed and flows from top to bottom into the 19th adsorption tower. The liquid from the 12th and 13th adsorption towers is mixed and flows from bottom to top into the 20th adsorption tower. The liquid from the 14th and 15th adsorption towers is mixed and flows from bottom to top into the 21st adsorption tower. The liquid from the 16th to 20th adsorption towers is discharged into the tail liquid tank 3.

[0050] The top feed area is an adsorption tower, numbered No. 22. The outlet of the No. 21 adsorption tower is connected to the inlet of the No. 22 adsorption tower. The top feed process is realized by feeding from bottom to top. The outlet of the No. 22 adsorption tower is equipped with online conductivity and pH monitoring equipment. The effluent with conductivity and pH values ​​lower than the set values ​​is discharged into the washing and dehydration tank 4, and the effluent with conductivity higher than the set values ​​is discharged into the adsorption tail liquid tank 3.

[0051] The elution section is equipped with eight adsorption towers and an elution water tank 4, numbered sequentially from the 23rd to the 30th adsorption towers. Two towers are connected in parallel and fed in series. The 23rd adsorption tower is connected in series with the 25th, 27th, and 29th adsorption towers, and the 24th adsorption tower is connected in series with the 26th, 28th, and 30th adsorption towers. The effluent from the 29th and 30th adsorption towers is qualified elution liquid and discharged into the qualified liquid tank 5. The outlet of the 30th adsorption tower is equipped with a conductivity monitoring device. If the conductivity is lower than the set value, the effluent is discharged into the rinsing and impurity removal tank 1; if the conductivity is higher than the set value, it is discharged into the qualified liquid tank 5.

[0052] In summary, this invention employs a segmented, multi-column, single-column adsorption process in a continuous ion exchange system. The first-stage adsorption involves multiple columns fed in parallel under low pressure. The second-stage adsorption feeds the same amount of material as the first-stage adsorption, with the feed rate being the combined total of the effluent from two or more columns in the first stage. This increases the feed rate to the second stage, raises the operating pressure, and enhances the adsorption process. The flow rate of the second-stage adsorption can be adjusted and controlled separately by each column in the first stage. The first stage uses high-concentration materials under low flow rate and low pressure conditions, while the second stage uses lower-concentration materials under high flow rate and higher pressure conditions. High-concentration materials fully utilize their concentration advantage; higher concentrations result in better adsorption. Maintaining low flow rates extends the hydraulic residence time with the adsorbent, allowing for a thorough reaction between the adsorbent and the material. Upon entering the second stage from the first stage, the material concentration decreases, but the material from multiple columns is now mixed into a single stream entering the second stage, increasing the flow rate, pressure, and feed load, further improving the adsorption effect.

[0053] Although the specific embodiments of the present utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present utility model. Those skilled in the art should understand that, based on the technical solutions disclosed in the present utility model, all modifications or variations that can be made by those skilled in the art without creative effort should be included within the scope of protection of the present utility model.

Claims

1. A continuous ion exchange system for improving the effect of lithium extraction from salt lakes by varying the speed and pressure, characterized in that: The system is divided into adsorption zone, elution impurity removal zone, elution zone and elution top material zone, and the system operation sequence is adsorption-elution impurity removal-elution-elution top material; the adsorption zone includes multiple adsorption towers and is provided with feed storage tank; the adsorption zone is divided into two-stage feeding, one-stage adsorption tower feeding liquid is fed in parallel, and every two groups of discharge liquid are combined into one group and enter two-stage adsorption tower; the two-stage adsorption tower discharge liquid enters tail liquid tank for collection or external discharge.

2. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 1, characterized in that: The first adsorption tower to the tenth adsorption tower are respectively one-stage adsorption tower feeding liquid, the first and second adsorption tower discharge liquid is combined into one group of material and enters the eleventh adsorption tower, the third and fourth adsorption tower discharge liquid is combined into one group of material and enters the twelfth adsorption tower, the fifth and sixth adsorption tower discharge liquid is combined into one group of material and enters the thirteenth adsorption tower, the seventh and eighth adsorption tower discharge liquid is combined into one group of material and enters the fourteenth adsorption tower, the ninth and tenth adsorption tower discharge liquid is combined into one group of material and enters the fifteenth adsorption tower, and the eleventh to fifteenth adsorption tower discharge liquid is discharged into adsorption tail liquid storage tank or externally discharged.

3. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 1, characterized in that: The elution impurity removal zone is provided with two to four adsorption towers, is divided into fast washing and slow washing, and the elution impurity removal liquid is low calcium magnesium water or pure water stored in the elution impurity removal tank.

4. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 1, characterized in that: The elution zone is provided with four to ten adsorption towers, is provided with elution qualified liquid tank, and the elution liquid is pure water or low concentration acid, and the adsorption towers adopt multiple tower parallel or series connection mode.

5. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 1, characterized in that: The elution top material zone is provided with one to four adsorption towers, is provided with elution liquid storage tank, and the elution top material liquid is pure water, adsorption tail liquid or air, and the adsorption towers adopt series connection or multiple tower parallel connection mode.

6. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 2, characterized in that: The adsorption tower feeding liquid includes but is not limited to salt lake raw brine, old brine, oil and gas field lithium-containing water or lithium precipitation mother liquor.

7. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 2, characterized in that: Conductivity or pH online monitoring equipment is arranged at the outlet of the end adsorption tower discharge liquid of the adsorption zone, low conductivity or low pH discharge liquid is externally discharged into low calcium magnesium water storage tank or elution water tank, and discharge liquid with higher set conductivity is discharged into tail liquid tank.

8. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 3, characterized in that: The adsorption tower connection mode of the elution impurity removal zone is series connection, parallel connection or multiple tower parallel connection mode, when four adsorption towers are provided, the first and second adsorption towers are fed in parallel, slow washing sequence is implemented, the discharge liquid is combined into one group and enters the third adsorption tower, the third adsorption tower discharge liquid enters the fourth adsorption tower, and fast washing sequence is implemented; when three adsorption towers are provided, the first and second adsorption towers are fed in parallel, slow washing sequence is implemented, the discharge liquid is combined into one group and enters the third adsorption tower, and fast washing sequence is implemented.

9. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 4, characterized in that: Conductivity or pH online monitoring equipment is arranged at the outlet of the first adsorption tower discharge liquid of the elution zone, low conductivity or high pH discharge liquid is externally discharged into low calcium magnesium water storage tank or elution water tank; pH or / and conductivity online monitoring equipment is arranged at the first-stage elution qualified liquid external discharge outlet, low conductivity high pH discharge liquid is externally discharged into low calcium magnesium water storage tank or elution water tank, and high conductivity low pH discharge liquid is externally discharged into qualified liquid storage tank; the qualified liquid transfer pumps are used to transport the liquid level balance between the elution qualified liquid storage tanks of each stage.

10. The continuous ion exchange system for improving the effect of extracting lithium from salt lake by changing speed and pressure according to claim 5, characterized in that: The elution top material area top material liquid enters the adsorption tower from bottom to top, the outlet of the material liquid is provided with an online conductivity monitoring device, the conductivity lower than the set conductivity is discharged into the elution water tank, and the conductivity higher than the set conductivity is discharged into the tail liquid tank; the feeding ports of the adsorption area parallel feeding adsorption tower, the elution impurity removal area parallel feeding adsorption tower, the elution area parallel feeding adsorption tower and the elution top material area adsorption tower are provided with pressure and flow monitoring devices.

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