A spiral flow channel type anti-silicone scale membrane-free electro-deionization reactor

Abstract

This application relates to the technical field of electro-deionization reactors, and more particularly to a spiral flow channel type anti-silicone scale membrane-free electro-deionization reactor. It includes a shell, an anode assembly and a cathode assembly arranged coaxially, forming a resin cavity filled with an ion exchange resin layer between them. A spiral flow guide is arranged within the resin cavity to form a spiral flow channel. The flow guide consists of multiple spiral flow guide plates arranged axially at intervals. The flow guide plates have through grooves with an included angle between adjacent through grooves, and spiral grooves and gradually varying spacing can be provided on the plate surface. This structure forces the water flow to rotate and advance, enhancing radial mixing and rapidly dispersing OH- near the cathode. ‑ Local enrichment inhibits silica polymerization and complex silicate deposition, reduces pressure drop growth and stabilizes effluent quality, thereby improving the long-term operational reliability of membrane-free EDI in high-silica water conditions.

Description

Technical Field

[0001] This application relates to the technical field of electrodeionization reactors, and more particularly to a spiral flow channel type anti-silicone scale membrane-free electrodeionization reactor. Background Technology

[0002] Electrodeionization (EDI) is a deep desalination technology that combines electro-driven ion migration with ion exchange. Typically, under the influence of a DC electric field, ions in the solution undergo directional migration within the ion exchange medium and conduction channels, resulting in low-conductivity permeable water. Under certain conditions, the ion exchange medium can be regenerated online. Compared to traditional mixed-bed resin systems, EDI offers advantages such as continuous water production, high automation, and low consumption of regeneration reagents. Therefore, it is widely used in applications such as electronic-grade ultrapure water, pharmaceutical water, fine chemical processing, and power plant makeup water.

[0003] However, one of the key bottlenecks to the long-term stable operation of EDI lies in scaling and fouling, especially in the area near the cathode, the concentration side, or local stagnant areas. Electrode reactions and water ionization can lead to a local increase in pH and high concentrations of OH-. - With the original water , , The combined action of metal ions and anions such as carbonate and silicate easily forms insoluble deposits, leading to increased pressure drop, increased resistance, fluctuations in the conductivity of the produced water, and even channel blockage and failure. For silica-containing water sources, especially in situations where soluble silica and colloidal / particulate silica are present simultaneously, scaling problems are even more pronounced: when local alkalinity increases or ionic strength changes, silica species easily polymerize, forming amorphous silica deposits; at the same time, metal ions can promote the formation of complex silicates, making the deposit layer denser and more difficult to clean, thus significantly shortening the equipment maintenance cycle and reducing the system's effective operating time. These problems are more typical under engineering requirements of high recovery rates, fluctuating water quality, and relaxed pretreatment conditions.

[0004] To reduce membrane fouling and membrane stack costs, recent years have seen the exploration of membrane-free or weakly membrane-based technologies. These technologies minimize the critical separating role of the ion exchange membrane in the system, instead relying on electrode reactions and coupling with the ion exchange medium to achieve desalination and regeneration. Typically, Chinese patent (CN101259440A) discloses a membrane-free ion exchange resin electroregeneration method based on an equivalent filter element electrode, utilizing electrode reactions and OH- generated by water ionization. - and The process involves reviving and regenerating the exhausted resin. Through coupling of a microporous filter electrode, pressure difference, and electric field / dragging force, the replaced counterions are introduced into the electrode filter and discharged into the electrochemical reaction system, thus achieving resin regeneration and eliminating the need for an ion exchange membrane. This approach provides a fundamental pathway for membrane-free electroregeneration, but it still presents engineering challenges in high-silica or fouling conditions: Firstly, in membrane-free structures, the local reaction environment near the resin bed and electrode is more direct, and high OH- concentrations are easily formed in the cathode vicinity. - Firstly, if the internal flow channel organization is insufficient or there is bypass short-flow, the residence time, velocity distribution, and radial mixing of the solution in the resin bed will be uneven, easily leading to localized supersaturation, localized gelation, and deposit accumulation. Secondly, colloidal / particulate silica is more easily captured and enriched in the resin bed pores and on the electrode surface, resulting in increased pressure drop and deteriorated mass transfer, thus forming a positive feedback-driven accelerated scaling. Therefore, relying solely on the basic idea of ​​membrane-free, electro-regeneration is often insufficient to achieve long-term stable anti-scaling operation under high silica water conditions.

[0005] From another technical perspective, existing technologies for addressing scaling issues in EDI (Electrodeionization) often suppress the localized accumulation of scale-forming ions by altering the flow path structure and flow organization. Chinese patent (CN1898416A) discloses a spiral electrodeionization device that constructs a labyrinthine extended flow path within a spiral-shaped pool and uses related structural organization to control the migration path of scale-forming substances and reduce the risk of scaling. This spiral / labyrinth flow path concept emphasizes mitigating scaling by extending the flow path, improving fluid distribution, and reducing dead zones, offering valuable insights. However, it should be noted that such schemes are mostly based on membrane EDI compartment structures or flow path designs that are sealed with compartments. The spiraling object is often the macroscopic flow path within a compartment or cavity. For the common electrode-resin bed compact coupling structure of membrane-free EDI reactors, especially the configuration in which coaxial electrodes form an annular resin cavity, if only the concept of a spiral flow channel in the general sense is introduced without strong constraints on bypass short flow and without controllable enhancement methods for radial mixing, solution flow around, local stagnation and local alkalization may still occur, thus failing to inhibit the rapid polymerization of silica and the deposition of composite silicates in the region near the cathode from a mechanistic perspective.

[0006] Furthermore, regarding the scaling mechanism and suppression strategies in membrane EDI systems, Chinese patent (CN1323279A) proposes methods such as reversing the flow direction between the dilution chamber and the concentration chamber to hinder scale formation, metal cation migration, and reduce the risk of scale formation on the membrane surface. The concentration chamber can also be further separated to suppress localized deposition caused by convective transport. This type of technology reflects the consensus in the field regarding the coupling relationship between flow organization, ion migration, and localized deposition. However, it mainly targets ion exchange membrane stack systems, focusing scaling control points on the membrane surface and the concentration chamber side. In membrane-free systems, the same membrane boundary conditions do not exist, and scaling-sensitive areas often shift to high-pH regions near the cathode and within the pore structure of the resin bed. Especially in silicon-containing systems, silica polymerization and silica gel deposition are extremely sensitive to local pH and residence time. Without a continuous, forced, and controllable radial mixing mechanism within the annular resin cavity, it is still difficult to avoid the rapid local enrichment and deposition of silicon species. In other words, while the countercurrent / compartmental separation concept of membrane EDI can provide a motivation for scale inhibition, it cannot directly solve the problem of silicon scale mechanism in membrane-free coaxial electrode-ring resin cavity structure.

[0007] In summary, while existing technologies have proposed improvements from the perspectives of membrane-free electroregeneration, spiral / labyrinth flow paths, and flow organization and fouling suppression in membrane-based EDI, they still have significant shortcomings in membrane-free EDI applications with high silica or colloidal silica content. One issue is the high OH content in the cathode vicinity region. - Micro-regions can easily induce rapid polymerization of silica. On the other hand, if there are bypass short-flows, dead zones, or insufficient radial mixing inside the annular resin chamber, the local residence time will be longer, and supersaturation will be more likely to occur, leading to the accumulation of silica / composite silicate deposits, manifested as a rapid increase in pressure drop and deterioration of product water indicators. Therefore, there is an urgent need for a reactor internal flow channel and guiding configuration more suitable for membrane-free coaxial electrode structures: one that can, without introducing an ion exchange membrane, design a forced, sealed, and controllable disturbance of the fluid path within the resin chamber to avoid bypass short-flows, enhance radial mixing, and weaken the local enrichment of alkaline species near the cathode, thereby significantly inhibiting silica scale formation and deposition, and improving the long-term operational stability and reliability of membrane-free EDI reactors under complex water quality conditions. Summary of the Invention

[0008] The technical objective of this invention is to address the issue that existing membrane-free EDI reactors are prone to OH- ions in the cathode vicinity when treating silica-containing water. -Localized enrichment, bypass flow, and dead zones lead to the rapid polymerization of silica and the formation of silica scale, which in turn causes increased pressure drop and fluctuations in product water quality. To address this issue, a spiral flow channel anti-silica scale membrane-free EDI reactor is provided. By constructing a continuous spiral flow channel within the annular resin chamber between coaxial electrodes and enhancing radial mixing, the reactor reduces localized high pH micro-zones and excessive residence time, thereby inhibiting silica scale deposition, improving the long-term operational stability and desalination efficiency of the membrane-free EDI, and extending the equipment's service life.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A spiral flow channel type anti-silicone scale membrane-free electro-deionization reactor, the reactor comprising:

[0011] A) A housing with an internal cavity and a first interface and a second interface, both communicating with the cavity, at opposite axial ends.

[0012] B) An anode assembly and a cathode assembly disposed within a receiving cavity, wherein the anode assembly is located on the axial side and the cathode assembly is located on the radially outer side, forming an annular resin cavity filled with an ion exchange resin layer between them.

[0013] It also includes a flow guide that is disposed in the resin cavity and forms a continuous spiral flow channel. The flow guide has an inner sealing edge and an outer sealing edge. The inner sealing edge is in circumferential sealing contact with the outer peripheral surface of the anode assembly, and the outer sealing edge is in circumferential sealing contact with the inner peripheral surface of the cathode assembly, so that the water to be treated avoids forming an axial bypass short flow between the flow guide and the electrode.

[0014] The flow guide is composed of at least two spiral flow guide sections connected in series along the axial direction. The spiral pitch of adjacent spiral flow guide sections is different, so that the spiral flow channel has a variable pitch distribution along the axial direction.

[0015] Each spiral guide section is provided with at least one through-slot to form a radial feed flow, and the phase angle of two adjacent through-slots in the circumferential direction satisfies This creates periodic radial disturbances and secondary vortices within the flow channel.

[0016] Preferably, the flow guide includes multiple spiral flow guide plates spaced apart along the axial direction, with adjacent spiral flow guide plates connected end to end or fixedly connected by a connecting section to form a continuous spiral flow channel.

[0017] Preferably, the axial spacing between adjacent spiral guide plates gradually increases or decreases along the direction from the first interface to the second interface to form the variable pitch distribution; wherein the axial spacing is defined as the shortest distance between two adjacent spiral guide plates in the direction of the shell axis.

[0018] Preferably, the through groove is disposed between the first and second surfaces of the spiral guide plate, and each spiral guide plate is provided with one through groove.

[0019] Preferably, the circumferential phase angle α between two adjacent through slots satisfies .

[0020] Preferably, each spiral guide plate has a spiral groove on its liquid-facing surface, with a groove depth of 0.2-1.5 mm and a groove width of 0.5-3.0 mm, to enhance secondary vortices and near-wall shear scouring.

[0021] Preferably, elastic sealing rings or sealing adhesive layers are provided between the inner sealing edge of the flow guide and the anode assembly, and between the outer sealing edge and the cathode assembly, respectively, to achieve circumferential sealing contact and suppress bypass short-flow.

[0022] Preferably, the cathode assembly is a cylindrical cathode body, the anode assembly is a columnar or tubular anode body, and the ratio of the inner radius of the cathode body to the outer radius of the anode body is (1.5-3):1.

[0023] Preferably, the anode assembly includes a first mounting plate, a second mounting plate, and a detachably mounted anode column. The anode column is provided with a mesh covering its outer periphery, and sealing plates are provided at both ends of the anode column to be sealed and connected to the mounting plate.

[0024] Preferably, the housing is configured such that in the processing mode, the water to be treated enters through the second interface and flows out through the first interface, and in the regeneration / rinsing mode, the regenerated water enters through the first interface and flows out through the second interface.

[0025] This invention forms a continuous spiral flow channel by setting a flow guide in the annular resin cavity between the coaxially arranged anode and cathode, and causes the fluid to be spirally propelled and strongly radially mixed in the resin bed. This significantly reduces the OH- induced by water ionization / electrode reactions in the cathode-adjacent region through its operating mechanism. - Localized enrichment and high-pH microregions reduce the rapid self-aggregation, gelation, and interaction of silicic acid species under localized high-alkaline conditions. , The probability of plasma forming composite silicates is reduced, effectively inhibiting the deposition of silica scale on the cathode surface, resin bed pores, and cavity walls. Simultaneously, the spiral flow channel disrupts dead water zones and short flow paths, resulting in a more uniform distribution of water velocity field and residence time, reducing the chance of local concentration and supersaturation deposition. This, in turn, lowers the rate of pressure drop increase, slows the rise in resistance and energy consumption degradation, and stably maintains the effluent conductivity and silica content. Furthermore, the flow-guiding structure enhances turbulence and near-wall shear scouring, promoting ion mass transfer to resin active sites and electrode interfaces and accelerating the removal of regeneration byproducts. This allows for more complete online resin regeneration and greater system robustness to influent fluctuations, ultimately achieving long-term stable and efficient operation of membrane-free EDI in complex silica-containing water conditions, extending maintenance cycles, and improving equipment lifespan. Attached Figure Description

[0026] Figure 1 This is an internal cross-sectional view of the Benshen spiral flow channel type anti-silicone scale membrane-free EDI reactor.

[0027] Figure 2 This is a schematic diagram of the structure of the cathode assembly and anode assembly in the embodiments of this application.

[0028] Figure 3 This is a schematic diagram of the flow guide in the embodiments of this application.

[0029] Figure 4 This is a top view of the guide component in an embodiment of this application.

[0030] In the figure: 1. Housing; 11. First interface; 12. Second interface; 13. Receiving cavity; 14. Resin cavity; 2. Anode assembly; 21. First mounting plate; 22. Second mounting plate; 23. Anode column; 24. First through hole; 25. Second through hole; 26. Anode body; 27. Wiring head; 28. Sealing plate; 29. ​​Cover mesh; 3. Cathode assembly; 4. Flow guide; 41. Flow guide plate; 42. First surface; 43. Second surface; 44. Through groove. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0032] I. Structural composition and connection relationship of the reactor of this invention

[0033] Reference Figure 1This application provides a spiral flow channel type anti-silicone scale membrane-free electro-deionization reactor, including a shell 1, an anode assembly 2, a cathode assembly 3, and a flow guide 4. A first interface 11 is provided at the top of the shell 1, and a second interface 12 is provided at the bottom of the shell 1. A receiving cavity 13 is formed inside the shell 1, and both the first interface 11 and the second interface 12 are connected to the receiving cavity 13. The anode assembly 2 and the cathode assembly 3 are both disposed inside the shell 1, with the anode assembly 2 located in the middle of the shell 1 and the cathode assembly 3 located outside the anode assembly 2. The cathode assembly 3 and the anode assembly 2 are coaxially arranged, and a resin cavity 14 is provided between the anode assembly 2 and the cathode assembly 3. An exchange resin layer (not shown in the figure) is disposed within the resin cavity 14. The flow guide 4 is spirally disposed within the resin cavity 14, forming a spiral flow channel within the resin cavity 14. The flow guide 4 is composed of at least two spiral flow guide sections connected in series along the axial direction, with different spiral pitches between adjacent spiral flow guide sections, resulting in a variable pitch distribution of the spiral flow channel along the axial direction.

[0034] Reference Figure 1 and Figure 2 Specifically, in this embodiment, the flow guide 4 includes multiple flow guide plates 41, each independently configured. Each flow guide plate 41 is a spiral plate, and they are spaced apart along the axial direction of the housing 1. The spacing between the flow guide plates 41 gradually increases from the first interface 11 towards the second interface 12. The spiral flow guide plate design causes the water flow velocity to gradually decrease as it flows through the resin chamber 14, increasing the contact time between the water and the exchange resin and improving the ion exchange efficiency. Furthermore, the flow guide plates 41 force the water flow to rotate forward, generating strong radial mixing, which can remove the high concentration of OH- generated near the cathode. - Ions are rapidly and uniformly dispersed throughout the flow channel, avoiding local accumulation on the cathode surface and resin bed, thereby inhibiting the rapid local polymerization of silica. The spiral flow channel can effectively destroy any dead water zones or short flow paths that may exist, ensuring that all water flows through at a relatively uniform flow rate, reducing the chance of silica becoming concentrated, oversaturated, and deposited due to excessive local residence time.

[0035] It is easy to understand that in other embodiments, the flow guide 4 includes multiple flow guide plates 41, with adjacent flow guide plates 41 connected end-to-end, meaning the tail end of one adjacent flow guide plate 41 is fixed to the head end of the next one by a connecting piece or welding. This structure further enhances the continuity and stability of the spiral flow channel, reduces turbulence in the water flow between the flow guide plates, and makes the swirling flow more uniform. In addition, each flow guide plate 41 has micro-spiral grooves on its surface, further enhancing the rotation and mixing effect of the fluid, making it suitable for high-hardness water treatment scenarios with higher requirements for silica scale inhibition. In some embodiments, each flow guide plate 41 is provided with a spiral flow channel, thereby further enhancing the swirling flow of the liquid in the resin cavity.

[0036] Reference Figure 3 and Figure 4 Furthermore, the guide plate 41 has a first surface 42 at its front end and a second surface 43 at its rear end. A through groove 44 is provided between the first surface 42 and the second surface 43 to form a radial replenishment flow. An included angle α is formed between two adjacent through grooves 44, satisfying: 90°≤α≤180°. In this embodiment, the included angle α between two adjacent through grooves 44 is preferably between 120° and 150°. By providing the through groove 44, the water flow generates a certain rotational force when flowing through the through groove 44, enhancing the turbulence effect of the water flow, preventing scale formation in the resin layer, and simultaneously improving the ion exchange efficiency. The inner wall of the guide member 4 contacts the anode body 26, and the outer wall of the guide member 4 contacts the cathode body. In this embodiment, a sealing structure is also provided between the guide member 4 and the anode body 26 and the cathode body. This can be a sealant or a sealing ring fitted around the outer periphery of the guide plate 41, etc., and is not limited here. This design allows the flow guide 4 to not only guide the flow but also serve as a supporting structure between the anode and cathode, enhancing the overall structural stability of the reactor. Simultaneously, the contact between the flow guide 4 and the electrodes prevents liquid from flowing through the gaps between the flow guide 4 and the cathode and anode bodies 26.

[0037] When the ion exchange resin in the reactor needs to be regenerated, the DC power supply powers the anode assembly 2 and the cathode assembly 3. The treated high-purity water enters from the first port 11 and flows from top to bottom. As the spacing between the guide plates 41 gradually increases from the first port 11 toward the second port 12, the flow rate of the high-purity water gradually increases as it flows from top to bottom. In addition, since the water to be treated flows from bottom to top, the ion exchange resin layer near the second port 12 is more prone to overload. Therefore, as the spacing between the guide plates 41 gradually increases from the first port 11 toward the second port 12, the high-purity water has a better effect on desorbing impurity ions. When flowing through the ion exchange resin layer, the high-purity water carries the desorbed impurity ions, and finally, the concentrated water containing the desorbed impurity ions flows out from the second port 12.

[0038] In some embodiments, the cross-sectional shape of the channel 44 can be trapezoidal, and the channel width gradually increases along the direction of high-purity water flow. This design causes the water flow to not only rotate when passing through the channel 44, but also to generate local acceleration and decompression effects, further enhancing the scouring effect on the resin surface where silica gel may be attached.

[0039] Reference Figure 1 and Figure 2The anode assembly 2 includes a first mounting plate 21, a second mounting plate 22, and an anode post 23. The first mounting plate 21 and the second mounting plate 22 are installed inside the housing 1. The first mounting plate 21 has a first through hole 24 that extends through the first mounting plate 21 along the axial direction of the housing 1. The second mounting plate 22 has a second through hole 25 that extends through the second mounting plate 22 along the axial direction of the housing 1. The anode post 23 is installed between the first mounting plate 21 and the second mounting plate 22. The anode post 23 is detachably connected to the first mounting plate 21 and the second mounting plate 22, specifically by screws and nuts. This detachable connection design facilitates later maintenance and replacement of the anode post 23, improving the service life and maintenance efficiency of the equipment.

[0040] The anode column 23 includes an anode body 26, a connector 27, a sealing plate 28, and a mesh cover 29. The connector 27 is connected to the top of the anode body 26, the sealing plate 28 is installed at both ends of the anode body 26, and the mesh cover 29 covers the outer periphery of the anode body 26. The sealing plate 28 is sealed to the first mounting plate 21 and the second mounting plate 22. This structural design ensures stable and reliable electrical connection of the anode column 23, while preventing short circuits in the water flow through the sealing connection of the sealing plate 28, thus improving electrolysis efficiency.

[0041] In some embodiments, the anode column 23 adopts a hollow tubular structure, through which cooling water can circulate to control the electrode operating temperature and prevent accelerated silica scale deposition due to excessively high local temperatures. The mesh 29 adopts a titanium-based metal oxide coated mesh, which ensures good conductivity and catalytic activity while improving corrosion resistance and mechanical strength. In addition, the anode column 23 is connected to the first mounting plate 21 and the second mounting plate 22 by quick-release clips, further simplifying the disassembly and maintenance process.

[0042] The cathode assembly 3 includes a cathode body. A first mounting plate 21 has a first mounting groove on the side facing the cathode body, and a second mounting plate 22 has a second mounting groove on the side facing the cathode body. The cathode body is inserted into the first and second mounting grooves. By snapping the cathode body into the first and second mounting grooves, the cathode body can be more stably fixed, while also facilitating installation and disassembly.

[0043] The radius ratio of the cathode body to the anode body 26 is (1.5-3):1. In a preferred embodiment, the radius ratio of the cathode body to the anode body 26 is 1.8:1. This ratio ensures sufficient resin storage space while making the electric field distribution more uniform, which is particularly suitable for treating water with moderate silicon content and small amounts of calcium and magnesium ions. At this ratio, the resin layer thickness is moderate, which is beneficial to the ion exchange capacity and avoids the problem of excessive pressure drop caused by an excessively thick resin layer.

[0044] II. Material Selection and Processing Assembly

[0045] Shell 1: Can be made of 316L stainless steel, duplex steel or PVDF lined shell; the surface in contact with water is preferably alkali resistant, wear resistant and chloride ion pitting resistant.

[0046] Deflector plate 41: Preferably made of electrically insulating and alkali-resistant material, such as PEEK, PVDF, PTFE or glass fiber reinforced PP; the processing method can be CNC cutting, hot pressing or 3D printing (optional in industrial verification stage).

[0047] Seals: EPDM, FKM or PTFE-coated sealing rings are preferred; they should not swell over a long period of time under high pH conditions.

[0048] Resin layer: preferably a mixture of strong acid cationic resin and strong base anionic resin is used for filling; before filling, it is soaked in deionized water, degassed, and washed until the effluent is clear.

[0049] Assembly steps: Install the cathode body into the housing 1 and position it with the mounting plate; install the flow guide 4 into the resin cavity 14, so that its outer wall fits against the cathode body; insert the anode column 23, so that the inner wall of the flow guide 4 fits against the anode body 26; fill the resin layer from top to bottom and gently vibrate to vent the air; finally install the end seal and the first / second interface pipeline.

[0050] III. Operating Mechanism Explanation

[0051] The implementation principle of this application embodiment is as follows: During operation, the water to be treated enters the reactor from the second interface 12, flows in the spiral flow channel formed by the guide member 4, and fully contacts the ion exchange resin layer for ion exchange, finally flowing out from 11; during regeneration, the DC power supply powers the anode assembly 2 and the cathode assembly 3, utilizing the generated H + ions or OH - Ions and H+ produced by direct current-induced water ionization + Ions and OH - Ions regenerate both the exhausted cation and anion exchange resins. Simultaneously, treated high-purity water enters through the first port 11, flowing from top to bottom. As it passes through the ion exchange resin layer, it carries away desorbed impurity ions. Finally, concentrated water containing these desorbed impurity ions flows out through the second port 12. The spiral flow channel design causes the water to flow in a spiral shape, increasing the contact area and contact time between the water and the resin. Simultaneously, the disturbance effect generated by the spiral flow effectively prevents the formation of silica scale, improving the reactor's lifespan and treatment efficiency.

[0052] IV. Basic Laboratory Experiments

[0053] All the following examples and comparative examples were performed on the same laboratory platform. Unless otherwise specified, the same test methods and criteria were used.

[0054] 1. Inlet water preparation (simulating high silica hardness and scale-promoting conditions, 25℃)

[0055] Simulated water was prepared using deionized water as a base:

[0056] Total silicon (in) count): mg / L (approximately 80 mg / L of soluble silica + approximately 40 mg / L of colloidal silica);

[0057] : mg / L; : mg / L;

[0058] Alkalinity (as CaCO3): mg / L;

[0059] Electrical conductivity: pH value: .

[0060] 2. Operating conditions and switching

[0061] Processing conditions: Flow rate 1.2L / min, constant voltage 28V continuous operation;

[0062] Regeneration / rinsing: Performed every 8 hours, with water entering through the first port 11 and draining through the second port 12, lasting for 10 minutes.

[0063] Operating cycle: 30 days (720 hours).

[0064] 3. Test Indicators and Methods

[0065] 1) Water conductivity (online);

[0066] 2) Total silica in effluent (as...) Calculation, spectrophotometry; total silicon was determined after acid hydrolysis of colloidal silica).

[0067] 3) Pressure drop in the resin chamber (Pressure difference between the two ends);

[0068] 4) Deposits: After shutdown and disassembly, the deposits on the cathode surface, the guide surface, and the cavity wall are collected by ultrasonic stripping, dried at 60℃ to constant weight, and weighed.

[0069] Instability Criteria: MPa or water conductivity If any condition is met, instability is determined.

[0070] V. Examples

[0071] Example 1

[0072] Cathode / anode radius ratio: 1.8:1; Number of guide plates 41: 5; Guide plate spacing (direction from first interface 11 to second interface 12): 8, 10, 12, 14, 16 mm (gradually increasing); Through slots 44: 3 per plate; Angle between adjacent through slots Each guide plate has a spiral groove on its surface: groove depth 0.6mm, groove width 1.2mm; the inner and outer walls of the guide plate are in contact with the anode / cathode (an alkali-resistant sealing ring is added if necessary). Other technical features are as described in sections one and two above, and will not be detailed in this embodiment.

[0073] Example 2

[0074] Cathode / anode radius ratio: 1.5:1; Number of guide plates: 6; Spacing: 7, 9, 11, 13, 15, 17 mm; Through slots: 2 per plate; Groove: groove depth 0.3mm, groove width 1.0mm; the rest is the same as in Example 1.

[0075] Example 3

[0076] Cathode / anode radius ratio: 2.8:1; Number of guide plates: 4; Spacing: 10, 12, 14, 16 mm; Through slots: 4 per plate; Groove: groove depth 1.0mm, groove width 2.0mm; the rest is the same as in Example 1.

[0077] VI. Comparative Example

[0078] Comparative Example 1

[0079] The flow guide 4 is removed, and only the coaxial electrode and resin cavity structure are retained. The rest is the same as in Example 1.

[0080] Comparative Example 2

[0081] The spiral guide plate is retained, but a 1-2 mm gap is left between the outer wall of the guide and the inner circumference of the cathode, and between the inner wall of the guide and the outer circumference of the anode, and no seal is provided to form a bypass short flow. The rest is the same as in Example 1.

[0082] Comparative Example 3

[0083] The spacing between the guide vanes is kept constant at 12mm (the structure of "gradually increasing from top to bottom" is cancelled), and the rest is the same as in Example 1.

[0084] Comparative Example 4

[0085] The included angle between adjacent through slots is set as follows: The rest is the same as in Example 1.

[0086] VII. Experimental Results and Data

[0087] Table 1 Comparison of 30-day operating performance

[0088]

[0089] Table 2. Mass of dismantled sediments (mg)

[0090]

[0091] VIII. Results Analysis

[0092] Examples 1-3 are essentially equivalent: within the scope of this application, changing the radius ratio, α, number of guide plates and spacing can still significantly reduce the pressure drop increase and total deposition, indicating that the present invention can be implemented within the scope of this application and achieve essentially the same anti-silicone scale effect.

[0093] Comparative Example 1 demonstrates the necessity of the "spiral channel": without the flow guide, the deposition increases significantly and the pressure drop rises rapidly, indicating that dead water zones / short flow and local high pH micro-regions at the cathode are more likely to form, and silica scale is more likely to deposit.

[0094] Comparative Example 2 demonstrates the necessity of "fitting / sealing to suppress bypass short flow": Although the guide plate exists, if a gap is left between it and the electrode to form a bypass short flow, the scale inhibition effect will be significantly worse, indicating that the fit (or sealing) between the guide plate and the electrode is crucial to forcing the fluid to pass through the spiral flow channel.

[0095] Comparative Example 3 demonstrates the contribution of "gradual spacing": there is still some improvement without gradual spacing, but it is not as good as in Example 1, indicating that gradual spacing helps to homogenize residence time and improve regeneration / rinsing carrying efficiency, thereby further inhibiting scale.

[0096] Comparative Example 4 demonstrates the rationality of the α range: when α is too small, it leads to a phase mismatch of disturbance, insufficient radial mixing, or the formation of an unfavorable backflow structure, which exacerbates deposition and pressure drop, proving that limiting the included angle range has engineering significance.

[0097] The foregoing description of embodiments of the present invention, through which those skilled in the art are able to implement or use the present invention, will be readily apparent to those skilled in the art. Various modifications to these embodiments will be readily apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novelty disclosed herein.

Claims

1. A spiral flow channel type anti-silicone scale membrane-free electro-deionization reactor, the reactor comprising: A) The housing (1) has a cavity (13) inside, and a first interface (11) and a second interface (12) that are connected to the cavity (13) respectively at opposite ends in the axial direction. B) An anode assembly (2) and a cathode assembly (3) are disposed in a receiving cavity (13), wherein the anode assembly (2) is located on the axial side and the cathode assembly (3) is located on the radial side, and an annular resin cavity (14) filled with an ion exchange resin layer is formed between the two. Its features are: It also includes a flow guide (4) disposed in the resin cavity (14) and forming a continuous spiral flow channel. The flow guide (4) has an inner sealing edge and an outer sealing edge. The inner sealing edge is in circumferential sealing contact with the outer peripheral surface of the anode assembly (2), and the outer sealing edge is in circumferential sealing contact with the inner peripheral surface of the cathode assembly (3), so that the water to be treated avoids forming an axial bypass short flow between the flow guide and the electrode. The guide element (4) is composed of at least two spiral guide sections connected in series along the axial direction. The spiral pitch of adjacent spiral guide sections is different, so that the spiral flow channel is distributed with a variable pitch along the axial direction. Each spiral guide section is provided with at least one through-slot (44) to form a radial feed flow, and the phase angle of two adjacent through-slots (44) in the circumferential direction satisfies This creates periodic radial disturbances and secondary vortices within the flow channel.

2. The reactor according to claim 1, characterized in that: The flow guide (4) includes multiple spiral flow guide plates (41) spaced apart along the axial direction. Adjacent spiral flow guide plates (41) are connected end to end or fixedly connected by a connecting section to form a continuous spiral flow channel.

3. The reactor according to claim 2, characterized in that: The axial spacing between adjacent spiral guide plates (41) gradually increases or decreases along the direction from the first interface (11) toward the second interface (12) to form the variable pitch distribution; The axial spacing is defined as the shortest distance between two adjacent helical guide plates along the axial direction of the shell.

4. The reactor according to claim 1, characterized in that: The through groove (44) is provided between the first side (42) and the second side (43) of the spiral guide plate (41), and each spiral guide plate (41) is provided with 2-6 through grooves (44).

5. The reactor according to claim 1, characterized in that: Circumferential phase angle of two adjacent through slots (44) satisfy .

6. The reactor according to claim 1, characterized in that: Each spiral guide plate (41) has a spiral groove on its liquid-facing surface, the groove having a depth of 0.2-1.5 mm and a width of 0.5-3.0 mm.

7. The reactor according to claim 1, characterized in that: An elastic sealing ring or sealing adhesive layer is respectively provided between the inner sealing edge of the flow guide (4) and the anode assembly (2), and between the outer sealing edge and the cathode assembly (3).

8. The reactor according to claim 1, characterized in that: The cathode assembly (3) is a cylindrical cathode body, and the anode assembly (2) is a columnar or tubular anode body (26), and the ratio of the inner radius of the cathode body to the outer radius of the anode body is (1.5-3):

1.

9. The reactor according to claim 1, characterized in that: The anode assembly (2) includes a first mounting plate (21), a second mounting plate (22), and a detachable anode column (23). The anode column (23) is provided with a mesh (29) around its outer periphery, and sealing plates (28) are provided at both ends of the anode column to seal and connect with the mounting plate.

10. The reactor according to claim 1, characterized in that: The housing (1) is configured such that in the processing mode, water to be treated enters through the second interface (12) and flows out through the first interface (11), and in the regeneration / rinsing mode, regenerated water enters through the first interface (11) and flows out through the second interface (12).

Images