Membrane-free electric deionized water treatment device and method based on radial electric field

Abstract

The invention relates to the technical field of water treatment, and particularly discloses a membrane-free electric deionized water treatment device and method based on a radial electric field, and the membrane-free electric deionized water treatment device comprises a cylindrical shell which is provided with a cavity, and the cavity is filled with an exchange resin layer; the central electrode is arranged in the cavity and is arranged in the middle of the exchange resin layer along the axial direction of the cylindrical shell; the peripheral electrode is arranged on the periphery of the exchange resin layer, the peripheral electrode and the central electrode are coaxially arranged, and a radial electric field is formed between the central electrode and the peripheral electrode; the central electrode is tubular, a central channel is formed in the central electrode, a micropore structure is formed in the central electrode, the micropore structure is communicated with the cavity and the central channel, a second pipeline is arranged on one side of the water outlet end of the cylindrical shell, and the second pipeline is communicated with the side, away from the first pipeline, of the central channel. The ion migration path is shortened, the ion migration speed and the processing efficiency are improved, and the energy consumption is reduced.

Description

Technical Field

[0001] This application relates to the field of water treatment technology, and in particular to a membrane-free electro-deionization water treatment device and method based on a radial electric field. Background Technology

[0002] The application of industrial high-purity water in industries such as chemical engineering, pharmaceuticals, microelectronics, and power generation is becoming increasingly widespread, and deep desalination technology, as the core of high-purity water production, has attracted much attention. In the past two decades, electrodeionization (EDI) technology has gradually replaced traditional ion exchange technology due to its advantages such as high treatment efficiency, environmental friendliness, and ease of operation. However, EDI technology also has problems such as complex device structure, difficult maintenance, high investment costs, and easy scaling of ion exchange membranes, all of which are related to the use of ion exchange membranes.

[0003] In recent years, with the development of membrane-free electrodeionization (MFEDI), a revolutionary technology compared to traditional EDI, the elimination of the ion exchange membrane simplifies the structure, while its operating principle becomes more dynamic and cyclical. By eliminating the membrane structure and employing cyclic operation, MFEDI sacrifices continuity for advantages such as structural simplification, cost reduction, and enhanced antifouling capabilities, making it a promising improvement technology. However, existing MFEDI devices mostly employ a parallel plate electrode structure, where the anode and cathode are placed parallel to each other at opposite ends of the resin bed. This results in ions needing to migrate from one end of the resin bed to the other, leading to a long path. Summary of the Invention

[0004] To address the issue of long ion migration paths in existing MFEDI devices, this application provides a membrane-free electro-deionization water treatment device and method based on a radial electric field.

[0005] This application provides a membrane-free electro-deionization water treatment device based on a radial electric field, which adopts the following technical solution: A membrane-free electro-deionization water treatment device based on a radial electric field, comprising: The cylindrical outer shell has a cavity filled with an exchange resin layer. The central electrode is disposed inside the cavity and is located in the middle of the exchange resin layer along the axial direction of the cylindrical outer shell. The central electrode has a first polarity. The peripheral electrode is disposed on the outer periphery of the exchange resin layer. The peripheral electrode is coaxially arranged with the central electrode. The peripheral electrode has a second polarity. A radial electric field is formed between the central electrode and the peripheral electrode. The cylindrical shell has a first pipe at one end, parallel to its axis. A water distributor is installed inside the cylindrical shell, and the first pipe is connected to the water distributor. The central electrode is tubular, and a central channel is installed inside the central electrode, parallel to the axis of the cylindrical shell. The central electrode has a microporous structure that connects the cavity and the central channel. A second pipe is installed on one side of the cylindrical shell at the water outlet, and the second pipe is connected to the side of the central channel away from the first pipe. A third pipe is installed at the end of the cavity near the first pipe, and the third pipe is connected to the central channel.

[0006] By adopting the above technical solution, a radial electric field is formed in the exchange resin layer through the coaxial arrangement of the central and peripheral electrodes. This significantly shortens the path for ions to migrate from the exchange resin layer to the electrodes, thereby improving ion migration speed and treatment efficiency while reducing energy consumption. Furthermore, the tubular design and microporous structure of the central electrode allow for efficient collection and discharge of pure water, which works well with the radial flow field, further optimizing the continuity and stability of the water treatment process. Simultaneously, the water distributor helps to ensure uniform flow of effluent into the exchange resin layer, promoting uniform water distribution and thus improving the efficiency of ion adsorption and regeneration processes.

[0007] In some embodiments, a first mounting plate and a second mounting plate are provided inside the cavity. The first mounting plate is installed on the side near the first pipe, and the second mounting plate is installed on the side near the water outlet. The second mounting plate is sealed to the inner wall of the cylindrical shell. A water trough is provided on the first mounting plate for the water from the water distributor to flow into the exchange resin layer.

[0008] By adopting the above technical solution and setting the first and second mounting plates, reliable encapsulation of the exchange resin layer is achieved, preventing resin particles from shifting or leaking under fluid impact, and ensuring the long-term stability of the device.

[0009] In some embodiments, a third pipe is provided at one end of the cavity near the first pipe, the axis of the third pipe is perpendicular to the first pipe, and the third pipe is located between the water distributor and the first mounting plate.

[0010] In some embodiments, the central electrode is installed between the first mounting plate and the second mounting plate. The central electrode includes a base tube and an electrode strip. A central channel is disposed inside the base tube. Multiple slots are provided on the outer wall of the base tube along the axial direction of the base tube. Adjacent slots are spaced apart along the circumference of the base tube. The electrode strip is embedded in the slot.

[0011] By adopting the above technical solution, the manufacturing and maintenance process of the electrode is simplified and the manufacturing cost is reduced by embedding the electrode strip in the slot of the base tube, while ensuring the stability and conductivity of the electrode strip.

[0012] In some embodiments, the outer diameter of the base pipe gradually increases along the first pipe toward the second pipe, and the inner diameter of the base pipe gradually increases along the first pipe toward the second pipe.

[0013] By adopting the above technical solution, a larger flow area is provided at the inlet end to cope with high flow rate and ion flux, and an appropriate flow velocity is maintained at the outlet end, thereby ensuring the uniformity of water treatment and regeneration effects along the entire axial length, which helps to improve overall efficiency and achieve better treatment results.

[0014] In some embodiments, the ratio between the outer diameter of the base pipe near the first pipe end and the outer diameter of the base pipe near the third pipe end is 1:(1.5~2).

[0015] By adopting the above technical solution and optimizing the ratio of the outer diameter of the inlet and outlet of the base pipe, the rationality of the conical design is ensured, the flow distribution and electric field strength are balanced, thereby optimizing the fluid dynamics and electrochemical performance in the water treatment process and improving the adaptability and efficiency of the device.

[0016] In some embodiments, the water distributor includes a spiral water distribution pipe connected to the first pipe, and the spiral water distribution pipe is provided with multiple water outlet holes, which are evenly distributed along the spiral water distribution pipe.

[0017] In some implementations, the pore size of the microporous structure on the side closer to the first channel is larger than the pore size of the microporous structure on the side closer to the second channel.

[0018] By adopting the above technical solution, the larger aperture at the inlet reduces water flow resistance and accommodates higher flow rates and ion fluxes; the smaller aperture at the outlet provides finer filtration, which helps to ensure the quality of pure water and the stability of the flow field, thereby optimizing the pure water collection process and improving the overall treatment efficiency.

[0019] In some embodiments, a resin cavity is formed between the central electrode and the peripheral electrode, and a flow guide plate is disposed in the resin cavity. The flow guide plate is sleeved on the central electrode and is coaxially arranged with the central electrode. The flow guide plate divides the volume of the resin cavity equally, and the permeability of the flow guide plate is greater than the permeability of the exchange resin layer.

[0020] On the other hand, this application also provides a membrane-free electro-deionization water treatment method based on a radial electric field, which employs the above-mentioned membrane-free electro-deionization water treatment device based on a radial electric field and includes the following steps: Adsorption steps: Raw water enters the water distributor through the first pipe and then enters the ion exchange resin layer; the ion exchange resin layer adsorbs ions in the raw water to obtain pure water, which enters the central channel through the microporous structure and is finally discharged from the second pipe. Regeneration steps: Stop the raw water supply, start the DC power supply, and apply DC voltage to the central and peripheral electrodes. Under the action of the radial electric field, anions in the exchange resin layer migrate towards the central electrode, and cations migrate towards the peripheral electrodes. Simultaneously, H+ generated by the electrode reaction... + and OH - The resin is regenerated, and finally the wastewater is discharged from the third pipe.

[0021] Compared with the prior art, this application includes at least one of the following beneficial technical effects: 1. By setting the central electrode and the peripheral electrode coaxially, a radial electric field is established between the exchange resin layers, which greatly shortens the path of ions migrating from the inside of the resin bed to the electrode. Compared with the traditional parallel plate electrode structure, the ion migration speed is faster and the resistance is smaller, so more ions can be processed per unit time, realizing an overall improvement in the desalination efficiency of the device, and reducing energy consumption due to the reduction of electromigration resistance. 2. By designing a water distributor and a frustum-shaped central electrode, the device can better adapt to the treatment effect at different positions along the axial length, and adapt to changes in flow rate and ion concentration, which helps to ensure the stability of the device during the treatment process and the uniformity of the treatment effect. 3. It integrates adsorption and regeneration functions, and switches the operating mode by switching water flow and electric field, which simplifies the internal structure of the device, reduces manufacturing and material costs, and reduces the difficulty of device maintenance. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the internal structure of an embodiment of this application.

[0023] Figure 2 This is a schematic diagram of the structure of the central electrode in an embodiment of this application.

[0024] Figure 3 This is an internal cross-sectional view of the central electrode in an embodiment of this application.

[0025] Figure 4 This is a schematic diagram of the water distributor in an embodiment of this application.

[0026] In the picture: 1. Cylindrical outer shell; 11. Cavity; 12. Exchange resin layer; 13. First pipe; 14. First mounting plate; 141. Water tank; 15. Second mounting plate; 16. Resin cavity; 17. Second pipe; 18. Third pipe; 2. Central electrode; 20. Central channel; 21. Base tube; 23. Slot; 24. First mounting post; 25. Second mounting post; 26. Microporous structure; 3. Peripheral electrode; 4. Water distributor; 41. Spiral water distribution pipe; 42. Water outlet; 5. Guide plate. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0028] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the term "and / or" in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Furthermore, the character " / " in this document, unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship.

[0029] Reference Figure 1 This application provides a membrane-free electro-deionization water treatment device based on a radial electric field, including a cylindrical shell 1, a central electrode 2, and peripheral electrodes 3. A cavity 11 is formed inside the cylindrical shell 1, and the cavity 11 is sealed. An exchange resin layer 12 is filled inside the cylindrical shell 1. The central electrode 2 and peripheral electrodes 3 are both disposed within the cavity 11. The central electrode 2 is positioned along the axial direction of the cylindrical shell 1 at the center of the exchange resin layer 12 and has a first polarity. The peripheral electrodes 3 are disposed on the outer periphery of the exchange resin layer 12 and are coaxially arranged with the central electrode 2. The peripheral electrodes 3 have a second polarity. When energized, a radial electric field is formed between the central electrode 2 and the peripheral electrodes 3. A resin cavity 16 is formed between the central electrode 2 and the peripheral electrodes 3, and the exchange resin layer 12 is specifically disposed within the resin cavity 16. One end of the cylindrical outer shell 1 is provided with a first pipe 13 parallel to the axis of the cylindrical outer shell 1. A water distributor 4 is provided inside the cylindrical outer shell 1. One end of the first pipe 13 is connected to the water distributor 4, and the other end extends to the outside of the cylindrical outer shell 1. The other end of the cylindrical outer shell 1 is provided with a second pipe 17 parallel to the axis of the cylindrical outer shell 1. The second pipe 17 is connected to the side of the central channel 20 away from the first pipe 13. The central electrode 2 is tubular. A central channel 20 is provided inside the central electrode 2 along the axis of the cylindrical outer shell 1. A microporous structure 26 is provided on the side wall of the central electrode 2. The microporous structure 26 connects the cavity 11 and the central channel 20.

[0030] Specifically, in this embodiment, the first polarity of the central electrode 2 is positive, and the second polarity of the peripheral electrode 3 is negative. In other embodiments, the first polarity of the central electrode 2 can be negative, and the second polarity of the peripheral electrode 3 can be positive; this is not limited here. In this embodiment, raw water enters the water distributor 4 from the first pipe 13. Under the action of the water distributor 4, the raw water is evenly distributed into the exchange resin layer 12. The exchange resin layer 12 adsorbs ions in the raw water to be treated, and the raw water is purified to obtain pure water. The pure water enters the central channel 20 through the microporous structure 26 and then flows out from the second pipe 17.

[0031] This application establishes a radial electric field within the exchange resin layer 12 by setting a central electrode 2 and a peripheral electrode 3. Compared with the electric field formed by a traditional parallel plate motor, this significantly shortens the path for ions to migrate from the exchange resin layer 12 to the central electrode 2 or the peripheral electrode 3, resulting in faster ion migration and higher efficiency. This leads to improved efficiency and reduced energy consumption in the membrane-free electro-deionization water treatment device. Furthermore, the microporous structure 26 enables the collection and export of pure water, forming a good match with the radial flow field.

[0032] Furthermore, a first mounting plate 14 and a second mounting plate 15 are disposed within the cavity 11. The central electrode 2 is mounted on the first mounting plate 14 and the second mounting plate 15. The first mounting plate 14 is mounted on the side near the first pipe 13, and the second mounting plate 15 is mounted on the side near the second pipe 17. The exchange resin layer 12 is disposed between the first mounting plate 14 and the second mounting plate 15. The first mounting plate 14 and the second mounting plate 15 are sealed to the inner wall of the cylindrical outer shell 1. Specifically, the sealing connection can be achieved by fitting sealing rings on the side walls of the first mounting plate 14 and the second mounting plate 15, which is not limited here. A water tank 141 is provided on the first mounting plate 14, which is used to supply water from the water distributor 4 to flow evenly into the exchange resin layer 12. By setting the first mounting plate 14 and the second mounting plate 15, reliable encapsulation of the exchange resin layer 12 is achieved, preventing resin particles from shifting or leaking under fluid impact, and ensuring the long-term stability of the device.

[0033] Reference Figure 2 and Figure 3Specifically, a first mounting post 24 is provided at the end of the central electrode 2 near the first mounting plate 14, and a second mounting post 25 is provided at the end of the central electrode 2 near the second mounting plate 15. Both the first mounting post 24 and the second mounting post 25 are coaxially arranged with the central electrode 2. The first mounting plate 14 has a first mounting hole for the first mounting post 24 to pass through, and the second mounting plate 15 has a second mounting hole for the second mounting post 25 to pass through. A first nut (not shown in the figure) is screwed onto the first mounting post 24, and a second nut (not shown in the figure) is screwed onto the second mounting post 25. By tightening the first nut and the second nut, the central electrode 2 can be installed. It is easy to understand that in some embodiments, the first mounting plate 14 and the second mounting plate 15 are slidably connected to the cavity 11. The first mounting plate 14 and the second mounting plate 15 can move along the axis of the cavity 11, thereby adjusting the volume of the resin cavity 16 and thus adjusting the density of the resin particles to adapt to different water treatment needs.

[0034] Furthermore, a third pipe 18 is provided at one end of the cavity 11 near the first pipe 13. The axis of the third pipe 18 is perpendicular to the first pipe 13. The third pipe 18 is connected to the central channel 20. When regeneration of the resin exchange layer is required, the raw water supply is stopped, the DC power supply is activated, and a pulsed DC voltage is applied to the central electrode 2 and the outer electrode. Pure water enters the central channel 20 from the second pipe 17, and then enters the exchange resin layer 12 through the microporous structure 26. Under the action of the radial electric field, anions migrate towards the central electrode 2, and cations migrate towards the outer electrode 3. At the same time, H+ generated by the electrode reaction... + and OH - The resin is regenerated.

[0035] By setting up a third pipe 18, during the regeneration stage, the third pipe 18 can discharge the gas generated by the electrode reaction, preventing it from re-contaminating the exchange resin layer 12 or forming scale. The third pipe 18 can efficiently carry the waste liquid away from the system, which helps to improve the regeneration efficiency and ensure the stable operation of the device.

[0036] It is easy to understand that in this embodiment, electric valves and water pumps are installed on the first pipe 13, the second pipe 17 and the third pipe 18. Electric valves and water pumps are existing technologies and will not be described again.

[0037] Furthermore, the central electrode 2 includes a base tube 21 and an electrode strip. A central channel 20 is disposed inside the base tube 21. Multiple slots 23 are formed on the outer wall of the base tube 21 along the axial direction of the base tube 21. Adjacent slots 23 are spaced apart circumferentially along the base tube 21. The electrode strip is embedded in the slots 23. By embedding the electrode strip in the slots 23, it is convenient to maintain and replace the electrode strip, reducing manufacturing costs.

[0038] Furthermore, the outer diameter of the base pipe 21 gradually increases along the first pipe 13 towards the second pipe 17, and the inner diameter of the base pipe 21 also gradually increases along the first pipe 13 towards the second pipe 17. That is, in this embodiment, the base pipe 21 is frustum-shaped, with the largest flow area at the inlet end, which can accommodate higher flow rates and current densities. As the water flows towards the outlet end, pure water is continuously collected, and the flow rate decreases. The conical design maintains appropriate flow velocity and electric field strength, thereby ensuring the uniformity of water treatment and regeneration effects along the entire axial length. The ratio between the outer diameter of the base pipe 21 near the first pipe 13 and the outer diameter of the base pipe 21 near the third pipe is 1:(1.5~2).

[0039] In this embodiment, the water distributor 4 includes a spiral water distribution pipe 41, which is connected to the first pipe 13. Multiple water outlet holes 42 are evenly distributed along the spiral water distribution pipe 41. This allows the single stream of water from the first pipe 13 to be converted into a uniformly distributed surface source water flow. The spiral structure itself has excellent flow field distribution capabilities, and combined with the uniformly distributed water outlet holes 42, it ensures that the raw water is injected from the end face of the entire annular resin bed at almost the same pressure and flow rate. This minimizes the phenomenon of excessively high or low local flow velocities, laying a uniform flow field foundation for subsequent deep desalination and efficient regeneration, and is a key guarantee for achieving high performance.

[0040] The pore size of the microporous structure 26 on the side near the first pipe 13 is larger than that on the side near the second pipe 17. On the side of the first pipe 13, the larger pore size can reduce inlet resistance and accommodate higher flow rates and ion fluxes; at the outlet, as pure water is continuously collected, the flow rate and ion load decrease, and the smaller pore size can provide a finer filtration effect, thereby ensuring a stable flow field.

[0041] Reference Figure 2A flow guide plate 5 is disposed within the resin exchange layer 12, and the flow guide plate 5 is sleeved on the central electrode 2. The flow guide plate 5 is coaxially arranged with the central electrode 2, and the flow guide plate 5 divides the volume of the resin cavity 16 equally. The flow guide plate 5 is made of sintered polymer. It is easy to understand that in this embodiment, there is one flow guide plate 5, which divides the volume of the resin cavity 16 in two. In other embodiments, there can be multiple flow guide plates 5. Taking two flow guide plates 5 as an example, the two flow guide plates 5 divide the volume of the resin cavity 16 into three. Specifically, in this embodiment, the sintered polymer can be porous PE or PP. The sintered polymer has high porosity, excellent insulation, and chemical stability. A flow guide plate made of sintered polymer is placed in the exchange resin layer 12. The permeability of the sintered polymer is much better than that of the exchange resin layer 12. Using the sintered polymer as a flow guide spacer can provide a good environment for the water flow in the exchange resin layer 12, and further ensure that the water flow is evenly distributed in the exchange resin layer 12.

[0042] In this embodiment, a guide plate 5 is also provided between the first mounting plate 14 and the exchange resin layer 12 to prevent resin particles from being lost under the action of water flow.

[0043] This application also provides a membrane-free electro-deionization water treatment method based on a radial electric field, employing the above-mentioned membrane-free electro-deionization water treatment device based on a radial electric field, including the following steps: Adsorption steps: Raw water enters the water distributor 4 from the first pipe 13 and then enters the exchange resin layer 12 through the water distributor 4; the exchange resin layer 12 adsorbs ions in the raw water to obtain pure water, which enters the central channel 20 through the microporous structure 26 and is finally discharged from the second pipe 17. At the inlet end of the adsorption step, the flow area is the largest, which can accommodate higher flow rates and current densities. As the water flows towards the outlet end, pure water is continuously collected, and the flow rate decreases. The frustum-shaped design of the base tube can maintain appropriate flow velocity and electric field strength, thereby ensuring the uniformity of water treatment effect along the entire axial length.

[0044] Regeneration Steps: Stop the raw water supply, start the DC power supply, and apply DC voltage to the central electrode 2 and peripheral electrode 3. Pure water enters the central channel 20 through the second pipe 17, and then enters the exchange resin layer 12 through the microporous structure 26. Under the action of the radial electric field, anions in the exchange resin layer 12 migrate towards the central electrode 2, and cations migrate towards the peripheral electrode 3. Simultaneously, H+ generated by the electrode reaction... + and OH - The resin is regenerated, and the wastewater is finally discharged from the third pipe 18. At the inlet end of the regeneration step, the flow area is the largest, which can accommodate a higher flow rate. As the water flows towards the outlet end, the wastewater is continuously collected and the flow rate decreases. The frustum-shaped design of the central channel 20 can maintain an appropriate flow velocity and ensure the uniformity of the regeneration effect along the entire axial length.

[0045] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A membrane-free electro-deionization water treatment device based on a radial electric field, characterized in that, include: The cylindrical outer shell (1) has a cavity (11) filled with an exchange resin layer (12); A central electrode (2) is disposed in the cavity (11). The central electrode (2) is disposed in the middle of the exchange resin layer (12) along the axial direction of the cylindrical shell (1). The central electrode (2) has a first polarity. The peripheral electrode (3) is disposed on the outer periphery of the exchange resin layer (12). The peripheral electrode (3) is coaxially disposed with the central electrode (2). The peripheral electrode (3) has a second polarity. A radial electric field is formed between the central electrode (2) and the peripheral electrode (3). The cylindrical shell (1) has a first pipe (13) at one end parallel to the axis of the cylindrical shell (1), a water distributor (4) inside the cylindrical shell (1), the first pipe (13) being connected to the water distributor (4), the central electrode (2) being tubular, a central channel (20) inside the central electrode (2) being parallel to the axis of the cylindrical shell (1), a microporous structure (26) on the central electrode (2), the microporous structure (26) being connected to the cavity (11) and the central channel (20), a second pipe (17) on one side of the water outlet of the cylindrical shell (1), the second pipe (17) being connected to the side of the central channel (20) away from the first pipe (13); a third pipe (18) is provided at one end of the cavity (11) near the first pipe (13), the third pipe (18) being connected to the central channel (20).

2. The membrane-free electro-deionization water treatment device based on a radial electric field according to claim 1, characterized in that, The cavity (11) is provided with a first mounting plate (14) and a second mounting plate (15). The first mounting plate (14) is installed on the side close to the first pipe (13), and the second mounting plate (15) is installed on the side close to the water outlet. The second mounting plate (15) is sealed to the inner wall of the cylindrical shell (1). A water tank (141) is provided on the first mounting plate (14). The water tank (141) is used to supply water from the water distributor (4) to flow into the exchange resin layer (12).

3. The membrane-free electro-deionization water treatment device based on a radial electric field according to claim 2, characterized in that, The axis of the third pipe (18) is perpendicular to the first pipe (13), and the third pipe (18) is located between the water distributor (4) and the first mounting plate (14).

4. The membrane-free electro-deionization water treatment device based on radial electric field according to claim 2, characterized in that, The central electrode (2) is installed between the first mounting plate (14) and the second mounting plate (15). The central electrode (2) includes a base tube (21) and an electrode strip. The central channel (20) is disposed inside the base tube (21). Multiple slots (23) are provided on the outer wall of the base tube (21) along the axial direction of the base tube (21). Adjacent slots (23) are spaced apart along the circumference of the base tube (21). The electrode strip is embedded in the slot (23).

5. A membrane-free electro-deionization water treatment device based on a radial electric field according to claim 4, characterized in that, The outer diameter of the base pipe (21) gradually increases along the first pipe (13) towards the second pipe (17), and the inner diameter of the base pipe (21) gradually increases along the first pipe (13) towards the second pipe (17).

6. The membrane-free electro-deionization water treatment device based on a radial electric field according to claim 4, characterized in that, The ratio between the outer diameter of the base tube (21) near the first pipe (13) and the outer diameter of the base tube (21) near the third pipe (18) is 1: (1.5~2).

7. The membrane-free electro-deionization water treatment device based on radial electric field according to claim 1, characterized in that, The water distributor (4) includes a spiral water distribution pipe (41), which is connected to the first pipe (13). The spiral water distribution pipe (41) is provided with a plurality of water outlet holes (42), which are evenly distributed along the spiral water distribution pipe (41).

8. The membrane-free electro-deionization water treatment device based on radial electric field according to claim 1, characterized in that, The pore diameter of the microporous structure (26) on the side closer to the first pipe (13) is larger than the pore diameter of the microporous structure (26) on the side closer to the second pipe (17).

9. A membrane-free electro-deionization water treatment device based on a radial electric field according to claim 1, characterized in that, A resin cavity (16) is formed between the central electrode (2) and the peripheral electrode (3). A guide plate (5) is provided in the resin cavity (16). The guide plate (5) is sleeved on the central electrode (2). The guide plate (5) is coaxially arranged with the central electrode (2). The guide plate (5) divides the volume of the resin cavity (16) equally. The permeability of the guide plate (5) is greater than the permeability of the exchange resin layer (12).

10. A membrane-free electro-deionization water treatment method based on a radial electric field, characterized in that, The membrane-free electro-deionization water treatment device based on radial electric field as described above includes the following steps: Adsorption steps: Raw water enters the water distributor (4) through the first pipe (13), and then enters the exchange resin layer (12) through the water distributor (4); the exchange resin layer (12) adsorbs ions in the raw water to obtain pure water, and the pure water enters the central channel (20) through the microporous structure (26), and finally exits from the second pipe (17). Regeneration steps: Stop the raw water supply, start the DC power supply, and apply DC voltage to the central electrode (2) and peripheral electrode (3). Under the action of the radial electric field, anions in the exchange resin layer (12) migrate to the central electrode (2), and cations migrate to the peripheral electrode (3). At the same time, H2 produced by the electrode reaction... + and OH - The resin is regenerated, and the wastewater is finally discharged from the third pipe (18).

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