A coaxial spiral anode replacement device and method for low-temperature multi-effect seawater desalination protection

Abstract

This application discloses a coaxial spiral anode replacement device and method for low-temperature multi-effect seawater desalination protection. The device includes an electrochemical ion exchange reactor, a monitoring system, and an intelligent control system. The reaction chamber is equipped with a coaxial spiral nested structure assembly, which includes an outer spiral anode, an inner spiral cathode, an anode storage chamber, a current collector, a telescopic controller, a fixed shaft, and a limiting lock pin. The outer spiral anode and the inner spiral cathode are coaxially arranged to form a spiral electrochemical reaction channel; the fixed shaft is used for coaxial positioning of the cathode and guiding the spare anode into the working position. The monitoring system detects the anode status, the intelligent control system controls the replacement of the spare anode, the limiting lock pin limits and fixes the anode, and the current collector restores the conductive connection, thereby improving the alignment stability and conductivity reliability after anode replacement.

Description

[0001] This application is a divisional application of the invention with application number "202610787904.6", application date June 3, 2026, and invention title "A potential compensation device for protecting a low-temperature multi-effect seawater desalination device". Technical Field

[0002] This application relates to the field of seawater desalination technology, specifically to a coaxial spiral anode replacement device and method for low-temperature multi-effect seawater desalination protection. Background Technology

[0003] Low-temperature multi-effect seawater desalination technology, with its advantage of low operating temperature, can fully utilize the 50-70℃ low-temperature waste heat generated by power plants and chemical plants. This process typically employs multiple multi-effect evaporators connected in series to achieve staged utilization of steam heat. However, in traditional series structures, the structures and functions of each multi-effect evaporator are basically the same, without functional differentiation design. During operation, motive steam flows within the heat exchange tube bundle, and the feed seawater is sprayed onto the outer wall of the heat exchange tube bundle through the spray tube bundle. Some of the seawater absorbs the latent heat of the steam and vaporizes to form secondary steam, which enters the next effect, thus achieving a multi-stage evaporation and condensation process, producing desalinated water several times the amount of steam.

[0004] Currently, to reduce the corrosive effects of impurities such as iron and manganese ions in seawater on the aluminum alloy heat exchange tube bundles of low-temperature multi-effect seawater desalination units, an electrochemical ion exchange reactor or aluminum alloy reaction medium is usually installed at the front end. However, after long-term operation, the aluminum alloy anode or reaction medium will be consumed, passivated, or covered with sludge, leading to a decrease in reaction efficiency and requiring periodic replacement. Existing replacement methods often require shutdown, drainage, or disassembly of equipment, making maintenance complex. For reaction structures with coaxial spiral anodes and cathodes, after replacement, it is also necessary to ensure the coaxial alignment and reliable conductive connection of the spare anode and cathode; otherwise, it can easily cause spiral flow channel misalignment, uneven electric field distribution, and a decrease in reaction efficiency.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] This application provides a coaxial spiral anode replacement device and method for low-temperature multi-effect seawater desalination protection, which solves the problems in existing low-temperature multi-effect seawater desalination electrochemical ion exchange reactors. When the consumable anode needs to be replaced after long-term operation, the maintenance process usually requires shutdown, drainage or disassembly of the equipment, which is complicated. Furthermore, for the reaction structure in which the coaxial spiral anode and cathode are matched, it is difficult to ensure the coaxial alignment stability and conductive connection reliability between the spare anode and the cathode after replacement, which can easily cause spiral flow channel misalignment, uneven current distribution and decreased reaction efficiency.

[0007] To solve the above-mentioned technical problems, this application adopts the following technical solution.

[0008] A coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection includes an electrochemical ion exchange reactor, a monitoring system, and an intelligent control system. The electrochemical ion exchange reactor includes a reaction chamber, which includes at least one replacement chamber. A coaxial spiral nested structure assembly is provided in the replacement chamber.

[0009] The replacement chamber is equipped with a front gate at the front end in the direction of water flow and a rear gate at the rear end in the direction of water flow. The replacement chamber is also connected to a drainage pressure balancing channel for draining residual seawater and achieving pressure balancing. Therefore, before anode replacement, the inlet flow channel of the replacement chamber containing the anode to be replaced can be isolated by the front gate, and the residual seawater in the replacement chamber can be drained and pressure balanced through the drainage pressure balancing channel, thereby reducing the risk of leakage during the replacement process.

[0010] The coaxial spiral nested structure assembly includes an outer spiral anode, an inner spiral cathode, an anode storage chamber, a current collector, a telescopic controller, a fixed shaft, and a limit locking pin.

[0011] The outer spiral anode is coaxially arranged around the inner spiral cathode, and the spiral parameters of the outer spiral anode and the inner spiral cathode are matched to form a spiral electrochemical reaction channel for seawater flow between them. This coaxial spiral arrangement maintains a relatively stable spacing between the anode and cathode and allows seawater to flow along the spiral electrochemical reaction channel.

[0012] The fixed shaft is coaxially fitted with the inner spiral cathode, used for coaxial positioning and axial support of the inner spiral cathode, and serves as an axial sliding support mechanism when the spare anode enters the working position. The limiting locking pin is located at the bottom of the fixed shaft and is used to engage with the locking through hole on the anode.

[0013] The anode storage chamber is used to store spare anodes, and the telescopic controller is connected to the top of the anode storage chamber. A retaining ring is provided at one end of the anode storage chamber away from the telescopic controller, and a fixing groove is provided at the other end for securing the spare anode. The retaining ring is used to limit the axial compression of the spare anode during axial movement of the anode storage chamber, and the fixing groove is used to temporarily secure the spare anode before it is deployed.

[0014] The telescopic controller is used to drive the anode storage chamber to move axially along the fixed axis, so that the spare anode is engaged with the limiting locking pin through the snap-fit ​​hole, and when the telescopic controller retracts, the spare anode is released and extended along the fixed axis to the working position coaxially nested with the inner spiral cathode after disengaging from the fixed groove.

[0015] In one optional embodiment, when the telescopic controller extends axially, it pushes the anode storage chamber to the position of the limiting lock pin, causing the snap-fit ​​hole of the spare anode to engage with the limiting lock pin, and pushing the anode to be replaced downwards to the limiting lock pin and disengaging from it. When the telescopic controller retracts, the anode storage chamber causes the spare anode to deform and disengage from the fixing groove, and the spare anode extends and releases along the fixing axis under the action of elastic deformation force. Thus, the axial movement of the anode storage chamber, the snap-fit ​​of the limiting lock pin, and the elastic release process of the spare anode itself can be used to complete the placement and positioning of the spare anode.

[0016] The current collector box is equipped with a flexible conductive end, and the outer spiral anode and / or spare anode are equipped with conductive connectors. The current collector box has a backup insulating state for disconnecting the conductive connection. The flexible conductive end is used to connect to the conductive connector after the spare anode enters the working position and completes its limiting and fixing, so that the spare anode is connected to the electrochemical reaction circuit. Thus, after the anode to be replaced is disconnected from the current collector box, the current collector box can enter a backup insulating state, reducing the risk of short-circuit current caused by accidental contact or positional misalignment during replacement; after the spare anode completes mechanical positioning, the conductive connection is restored through the flexible conductive end.

[0017] The monitoring system is used to detect the potential state or consumption state of the anode, and the intelligent control system is used to control the front-end gate, the drainage pressure balance channel, the telescopic controller and the collector box to perform anode replacement based on the detection results of the monitoring system.

[0018] In one optional embodiment, the intelligent control system is used to control the front gate to close to isolate the water inlet channel of the replacement chamber where the anode to be replaced is located when it is determined that the anode to be replaced meets the replacement conditions, and to keep the rear gate open to form a valve cavity between the front gate and the rear gate.

[0019] In one alternative embodiment, the outer spiral anode is a spiral corrugated plate aluminum alloy anode, and the inner spiral cathode is a spiral corrugated plate cathode. The pitch, diameter, and direction of rotation of the outer spiral anode and the inner spiral cathode are matched so that the spiral electrochemical reaction channel extends continuously along the axial direction of the fixed axis.

[0020] In one alternative embodiment, the inner spiral cathode is provided with a central hole and a limiting groove that cooperate with the fixed shaft. The fixed shaft cooperates with the central hole, and the limiting locking pin cooperates with the limiting groove to limit the radial displacement of the inner spiral cathode relative to the outer spiral anode.

[0021] In one optional embodiment, multiple spare anodes are stacked in the anode storage chamber, with a partition plate between adjacent spare anodes. The spare anode is a spiral anode that can be compressed under axial external force and released and extended after the axial external force is released, and one end of the spare anode is provided with a snap-fit ​​through hole that cooperates with the limiting locking pin.

[0022] In one optional embodiment, the current collector is used to disconnect the conductive connection with the anode to be replaced when the axial fixation is released, and to switch to the standby insulation state after the conductive connection is disconnected; the elastic conductive end is used to elastically abut against the conductive connector of the standby anode after the standby anode is fixed by the limiting locking pin, so as to restore the conductive connection between the standby anode and the current collector.

[0023] In one optional embodiment, the intelligent control system is further configured to initiate a small current test after the backup anode reaches a preset position, and confirm the current distribution state of the backup anode based on the detection results of the potential difference of each spiral segment of the backup anode; when the current distribution state meets the preset conditions, control the elastic conductive end of the current collector box to conduct with the conductive connector of the backup anode.

[0024] This application also provides a method for replacing a coaxial spiral anode for low-temperature multi-effect seawater desalination protection, using the aforementioned coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection. The method includes the following steps: The monitoring system detects the potential and consumption status of the anode, and the intelligent control system determines whether the anode meets the replacement conditions. When the anode meets the replacement conditions, the front gate of the replacement chamber where the anode to be replaced is located is closed to isolate the flow channel, and the rear gate is kept open to form an intervalve cavity. Drain the residual seawater in the replacement chamber where the anode to be replaced is located and perform pressure equalization; Release the axial fixation of the anode to be replaced, disconnect the conductive connection between the anode to be replaced and the current collector box, and switch the current collector box to the standby insulation state; The telescopic controller is axially extended to push the anode storage chamber to move axially along the fixed shaft, so that the snap-fit ​​hole of the spare anode engages with the limit lock pin, and the anode to be replaced is compressed below the limit lock pin. Control the telescopic controller to retract, so that the anode storage chamber is brought back to its original position, and the spare anode is released and extended along the fixed axis after being detached from the fixed groove of the anode storage chamber to the working position coaxially nested with the inner spiral cathode; After the backup anode reaches the preset position, the backup anode is axially fixed by the limiting locking pin, and the intelligent control system starts a small current test to detect the potential difference of each spiral segment of the backup anode. When the potential difference of each spiral segment of the backup anode meets the preset condition, the elastic conductive end of the current collector is connected to the conductive connector of the backup anode to restore the electrochemical reaction circuit. The anode to be replaced, compressed below the limiting locking pin, continues to contact seawater and participate in the reaction as an auxiliary anode. After the auxiliary anode corrodes and breaks, it is intercepted and discharged through the filter element of the filtration chamber.

[0025] Compared with the prior art, this application has at least the following beneficial effects: 1. This application forms a spiral electrochemical reaction channel between the outer spiral anode and the inner spiral cathode through coaxial nesting, which is beneficial to improving the stability of the seawater flow path and the electrode reaction area.

[0026] 2. This application uses a fixed shaft to simultaneously position and support the inner spiral cathode coaxially, and also serves as an axial guide reference when the spare anode enters the working position. This ensures that the spare anode can maintain a relatively stable coaxial fit with the inner spiral cathode after replacement, reducing the risk of spiral flow channel deviation and uneven electric field distribution.

[0027] 3. This application uses a limiting locking pin to limit and fix the spare anode, and connects the elastic conductive end of the current collector box to the conductive connector of the spare anode, so that the spare anode can be reliably connected to the electrochemical reaction circuit after entering the working position, thereby improving the reliability of conductivity recovery after anode replacement.

[0028] 4. This application uses a monitoring system to detect the anode potential status or consumption status, and an intelligent control system to control anode replacement and confirm the conductive connection status, which helps to reduce the impact of manual judgment and disassembly and maintenance on the continuous operation of the low-temperature multi-effect seawater desalination system. Attached Figure Description

[0029] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic diagram of the potential compensation device for protecting a low-temperature multi-effect seawater desalination device provided by the present invention. Figure 2 This is a schematic diagram of the first replacement chamber provided by the present invention; Figure 3 This is a schematic diagram of the coaxial spiral nested structure component provided by the present invention; Figure 4 A schematic diagram of the filter chamber provided by this invention; Figure 5This is a schematic diagram of an embodiment of the nested structure of the first replacement chamber, the second replacement chamber, and the third replacement chamber provided by the present invention; Figure 6 This is a schematic diagram of the potential gradient design of the present invention.

[0030] in: 1-Electrochemical ion exchange reactor; 2-Power supply system; 3-Monitoring system; 4-Intelligent control system; 5-Reaction chamber; 6-First replacement chamber; 7-Second replacement chamber; 8-Third replacement chamber; 9-Anode; 10-Cathode; 11-Anode storage chamber; 12-Collector box; 13-Telescopic controller; 14-Fixed shaft; 15-Limit locking pin; 16-Filter chamber. Detailed Implementation

[0031] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0032] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "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 the invention and for 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 the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed connection, detachable connection, or integral connection; they can refer to mechanical connection or electrical connection; they can refer to direct connection or indirect connection through an intermediate medium; and they can refer to the connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0034] To more clearly illustrate the technical solutions in this invention, specific embodiments are described below.

[0035] Example 1

[0036] This embodiment provides a coaxial spiral anode replacement device and method for low-temperature multi-effect seawater desalination protection. It is mainly to solve the problems in the prior art such as seawater corrosion of aluminum alloy heat exchange tube bundles, the influence of sludge adhesion on the ion exchange process, high maintenance cost of ion exchange system, low operating efficiency of seawater desalination device and failure of desalinated water quality to meet recycling standards.

[0037] In this embodiment, as Figure 1 As shown, the potential compensation device is applied to a low-temperature multi-effect seawater desalination device, which includes an electrochemical ion exchange reactor 1, a power supply system 2, a monitoring system 3, and an intelligent control system 4.

[0038] In this embodiment, the electrochemical ion exchange reactor 1 includes an anode 9, a cathode 10, and a reaction chamber 5; Among them, anode 9 is made of aluminum alloy (such as 5052) as the main material. Its main function is to make aluminum undergo an oxidation reaction under the action of electric current, lose electrons and dissolve to produce Al. 3+ (Aluminum ions); Anode 9 reaction (anode 9 surface): The aluminum alloy spontaneously oxidizes and dissolves, losing electrons, that is: (Electrode reaction formula 1); The spiral structure increases the specific surface area, allowing aluminum ions to diffuse rapidly into seawater (the diffusion rate is 2.5 times that of traditional aluminum rings). The cathode employs a composite structure with a stainless steel substrate and a Ni-Co-P catalyst layer, which can effectively receive electrons released from the anode 9, driving differentiated redox transformation of iron and manganese ions in seawater in the near-interface region of the cathode. 2+ Instead of direct electro-oxidation on the cathode electrode surface, the active oxide species generated by activating dissolved oxygen through the Ni-Co-P catalytic layer are indirectly oxidized around the cathode interface to generate manganese dioxide. Iron ions, on the other hand, directly gain electrons on the cathode surface and undergo electro-reduction, transforming into elemental iron in a directional manner. This achieves the stepwise conversion and separation of iron and manganese ions in seawater.

[0039] 1. Anode process: Anode 9 is made of aluminum alloy (such as 5052). Under the action of an applied current, aluminum undergoes oxidation and dissolution. The dominant reaction is that aluminum atoms lose 3 electrons to generate aluminum ions. The dissolved product rapidly hydrolyzes in the weakly alkaline environment of seawater. The weakly alkaline condition refers to a pH of 8-9, generating aluminum hydroxide colloid with flocculation effect.

[0040] 2. Cathode process: The standard electrode potential for ferric ions in seawater to gain electrons and generate ferrous ions in seawater is +0.77V, both of which are reduction potentials relative to the standard hydrogen electrode. The standard electrode potential for ferrous ions in seawater to gain electrons and form solid iron is -0.44V, which is the reduction potential relative to the standard hydrogen electrode.

[0041] divalent manganese ions (Mn) in seawater 2+ Under weakly alkaline conditions, it is oxidized, losing electrons to form manganese dioxide (MnO2) precipitate. These conditions refer to a pH of 8–9. 2+ The equilibrium potential of the MnO2 redox couple is approximately +0.3V, which is significantly higher than the cathode potential set by this system. Therefore, MnO2 will not be reduced by the cathode and can exist stably.

[0042] It should be noted that in actual seawater, the reduction potential is in a relatively positive range. Therefore, applying a suitable negative potential to the cathode 10 can drive the reactions in the first replacement chamber 6 and the second replacement chamber 7 to proceed smoothly. To avoid the reverse reduction of manganese dioxide in the third chamber 8, and to ensure that the potential of the third chamber is maintained at +0.435V to +0.565V, the cathode potentials of the first replacement chamber 6 and the second replacement chamber 7 are optimized to -0.4V to -0.6V. The ferric ion gains an electron and is reduced to the ferrous ion, that is: (Electrode reaction formula 2); The ferrous ion gains two more electrons and is reduced to metallic iron, i.e.: (Electrode reaction formula 3); The primary function of the stainless steel electrode with a Ni-Co-P catalytic layer, cathode 10, is to efficiently catalyze redox reactions to ensure a smooth current circuit and stable cathode potential. Its key function is the catalytic reduction of ferric ions (Fe3+) in colloidal form in seawater. 3+ The colloid promotes the conversion of soluble ferrous ions (Fe2+) into soluble ferrous ions. 2+ The transformation of ferric ions into ferrous ions is mainly accomplished in the first substitution chamber 6, where ferric ions gain electrons to form ferrous ions. This step disrupts the stable state of iron, creating conditions for its subsequent precipitation. The formation of elemental iron from ferrous ions is mainly accomplished in the second substitution chamber 7.

[0043] In this embodiment, as Figure 1As shown, the reaction chamber 5 includes, from top to bottom, a first displacement chamber 6, a second displacement chamber 7, a third displacement chamber 8, and a filter chamber 16. It is made of corrosion-resistant plastic material and contains an anode 9 and a cathode 10, forming a closed reaction space. Seawater flows in from one end of the reaction chamber 5. Under the action of an electric field, the cations in the seawater migrate to the cathode 10 and react. The treated seawater flows out from the other end. like Figure 3 As shown, the anode 9 is shaped like a spiral corrugated plate, replacing the traditional aluminum ring. The cathode 10 and anode 9 form a coaxial spiral nested structure assembly, which, from top to bottom, also includes a current collector 12, a telescopic controller 13, an anode storage chamber 11, and a fixed shaft 14. A limiting pin 15 is provided on the bottom of the fixed shaft 14. The fixed shaft 14 and the cathode 10 are coaxially positioned and assembled, providing axial support and positioning reference for the cathode 10. The coaxial arrangement of the two ensures the precise alignment of the coaxial spiral nested structure of the cathode 10 and the anode 9. The limiting pin 15 and other structures of the fixed shaft 14 work together with the cathode 10 to maintain the stability of the cathode 10 position during the replacement of the anode 9, avoiding displacement due to the removal or installation of the anode 9, and ensuring the precise connection of the spiral structure of the anode 9 and the cathode 10 and the uniformity of current distribution.

[0044] like Figure 3As shown, the anode 9 has a spiral corrugated plate structure, which, together with the mirror-fitted cathode 10, forms a coaxial spiral nested structure assembly. This assembly integrates, from top to bottom, a current collector 12, a telescopic controller 13, an anode storage chamber 11, and a fixed shaft 14. The fixed shaft 14 has a limiting locking pin 15 at its bottom. The precise nesting of the spiral structures of the anode 9 and cathode 10 utilizes their potential difference to spontaneously form a galvanic cell circuit. Simultaneously, the spiral flow channel enhances seawater disturbance to improve ion mass transfer efficiency, overcoming the inefficient mass transfer problem of traditional distributed electrodes. The current collector 12 achieves parallel conduction of each anode 9 through a snap-fit ​​connection with the quick-plug terminal at the top of the anode 9, avoiding current fluctuations caused by series conduction and ensuring uniform current distribution to support the staged potential control of each replacement chamber. The telescopic controller 13 initiates a linkage action under the command of the intelligent control system 4. Its drive component can axially push the anode storage chamber 11 along the fixed shaft 14. The anode storage chamber 11 contains stacked spare ions. The anode 9 is temporarily fixed by an elastic positioning buckle on the side wall of the replacement chamber. This buckle automatically retracts and unlocks under driving pressure, precisely releasing a single spare anode 9 to the assembly path, which is different from the cumbersome operation of traditional manual single-filling. At the same time, the fixed shaft 14 forms a coaxial positioning constraint with the adaptation structure of the central hole of the cathode 10, providing stable axial support for the cathode 10 and avoiding radial displacement that is easy to occur with traditional simple support. When the old anode 9 is removed, the elastic claw of the limit locking pin 15 automatically pops up and engages with the limit groove at the bottom of the cathode 10. After the spare anode 9 is pushed by the telescopic controller 13 and guided along the fixed shaft 14 to the preset position and completes the snap-fit ​​conductive connection with the current collector box 12, the limit locking pin 15 retracts and resets under the command of the intelligent control system 4. The entire process is coordinated by the functions of driving release, positioning support, and limit locking, thereby ensuring the precise connection between the anode 9 and the cathode 10 and avoiding problems such as uneven electric field distribution or reduced reaction efficiency caused by displacement.

[0045] like Figure 2 As shown, within the first replacement chamber 6, coaxial spiral nested structure components are evenly arranged along the circumferential direction. Multiple coaxial spiral nested structure components form a "ring array," i.e., a coaxial spiral nested structure module. This module is constructed via a central shaft, upper and lower partitions, gears, and mechanical limiting sliders. After rotation, the gears and limiting blocks engage and lock the module. Specifically, partitions are provided, each with circular through holes evenly distributed circumferentially. The coaxial spiral nested structure components are fixed to the partitions through these through holes, forming a coaxial spiral nested structure module with the partitions.

[0046] The surface area of ​​anode 9 is designed to expand and contract according to the flow rate and ion concentration of the seawater being treated; the first replacement chamber 6 has a central shaft with the center of the upper and lower partitions as the support point. The central shaft is fixedly connected to the upper and lower ends of the first replacement chamber 6. The partitions are set on the central shaft through bearings, and the center point of the partitions coincides with the center line of the central shaft. With this configuration, the coaxial spiral nested structure module can rotate along the central shaft. When it is necessary to replace the coaxial spiral nested structure component, the coaxial spiral nested structure module is rotated to replace the coaxial spiral nested structure component.

[0047] To ensure the rotation effect of the coaxial spiral nested structure module, in this embodiment, the coaxial spiral nested structure module is connected to the side wall of the first replacement chamber 6 via a bearing. Furthermore, to prevent the coaxial spiral nested structure module from rotating during operation, a mechanical limit slider is also provided to limit its movement. The coaxial spiral nested structure module can be rotated manually or controlled by the intelligent control system 4.

[0048] The mechanical limiting slider can be set on the central shaft or on the side wall of the first replacement chamber 6. The mechanical limiting slider is a meshing limiting block that meshes with a gear. When the mechanical limiting slider is set on the central shaft, the limiting block is set on the central shaft and the gear is set on the partition. When the mechanical limiting slider is set on the side wall of the first replacement chamber 6, the limiting block is set on the side wall of the first replacement chamber 6 and the gear is set on the partition. The limiting block can be controlled manually or by the intelligent control system 4.

[0049] In this embodiment, the first replacement chamber 6, the second replacement chamber 7, and the third replacement chamber 8 are arranged in series with pipelines and circuits, and the loop current is equal everywhere under the series operation condition; each chamber is an independent reaction system, and the anode potential, cathode potential, and chamber potential difference of each chamber are independent of each other, and the redox reaction potential window of each chamber can be adjusted separately to achieve stepwise selective redox and replacement of different metal ions.

[0050] To ensure good electric field distribution and ion exchange effect, such as Figure 3 As shown, the cathode 10 and anode 9 are arranged in parallel. The cathode 10 and anode 9 adopt a coaxial spiral nested structure. The outer spiral anode 9 and the inner spiral cathode 10 are coaxially arranged in the cylindrical first displacement chamber 6, the cylindrical second displacement chamber 7 and the cylindrical third displacement chamber 8. By utilizing the "flow channel extension and turbulence enhancement" characteristics of the spiral structure, the problems of low mass transfer efficiency and insufficient reaction contact of traditional flat plate or columnar electrodes are solved.

[0051] In this embodiment, as Figure 4As shown, several filter elements are arranged inside the filtration chamber 16. Their functions are: first, to filter and intercept anode debris and oxidation products that fall off during the operation of the first replacement chamber 6, the second replacement chamber 7, and the third replacement chamber 8, as well as during the replacement of the anode 9; second, to efficiently intercept silt and suspended impurity particles carried in the seawater, while protecting the subsequent pipelines and equipment from wear and tear, and ensuring the long-term stable operation of the seawater desalination unit.

[0052] In this embodiment, as Figure 3 As shown, the anode storage chamber 11 stores new anodes 9. The anode storage chamber 11 is located above the anodes 9, and it stores 3 to 4 spiral-shaped new anodes 9 inside. The new anodes 9 are separated by partition plates. When the intelligent control system 4 determines that the anodes 9 need to be replaced through potential monitoring and thickness detection, the anode storage chamber 11 pops out new anodes 9 to fill and replace the old anodes 9.

[0053] The system is primarily driven by an external power source, with the spontaneous reaction of the galvanic cell serving only as an auxiliary energy-saving measure (it does not participate in the core electron supply when the anode potential is too low), as detailed below: 1. When the anode 9 has sufficient activity (i.e., the anode working potential WCP ≤ -1.55V): At this point, the anode 9 has high surface activity and a negative potential, forming a stable potential difference with the cathode 10, enabling it to spontaneously initiate a galvanic cell reaction to provide core electrons. Therefore, the system can appropriately reduce the external current or utilize the galvanic cell reaction to supplement energy, achieving energy saving.

[0054] 2. When the activity of anode 9 decays (i.e., the anode operating potential WCP > -1.55V): At this point, an oxide film, slime coverage, or localized passivation appears on the surface of anode 9, causing a positive potential shift, reduced electron release capacity, and a significant weakening of the galvanic cell reaction. Therefore, the system shuts down the galvanic cell auxiliary mode and immediately activates power system 2, precisely compensating for electron supply through external current to prevent reaction failure.

[0055] Basic approach: Always rely on external current regulation to ensure stable system operation; only allow spontaneous reaction of the galvanic cell as an auxiliary energy-saving means when the anode potential activity is sufficient and the potential is stable; when the anode potential activity decays and the potential shifts positively, rely entirely on external current to drive the system and reduce the participation of spontaneous reaction in the core electron supply.

[0056] In this embodiment, the cathode 10 and anode 9 are designed with matching helical parameters, such as pitch, diameter, and direction of rotation, to create continuous disturbance of seawater within the helical flow channel. Simultaneously, the potential difference between the anode 9 and cathode 10 spontaneously forms a galvanic cell circuit, realizing Fe... 3+ Mn 2+Targeted conversion and efficient removal. The top of the anode 9 is equipped with a quick-plug terminal, which is connected to the current collector 12 by a snap-fit. The current is collected from the top of each spiral anode 9 to the current collector 12, realizing series conduction of each spiral anode 9 and ensuring uniform current distribution.

[0057] In practice, to further improve the system's compactness and processing efficiency, the anode 9 and cathode 10 can be designed as built-in structures and installed inside the seawater pipeline to reduce the volume of the reaction chamber 5.

[0058] In this embodiment, the power supply system 2 adopts an adjustable DC power supply, which can provide stable DC voltage and current. The output voltage range is 0-10V, and the output current range is 0-20A, which can be adjusted according to the actual operating requirements of the electrochemical ion exchange reactor 1. The power supply regulation module precisely regulates the output voltage and current of the DC power supply according to the instructions of the intelligent control system 4. It employs pulse width modulation technology to achieve rapid response and precise control of the power output, ensuring stable operation of the reactor under different operating conditions. In practice, the power supply system 2 can also use a pulse power supply to provide high-energy pulse current in a short time, thereby improving the dissolution rate of the anode 9 and the reduction capacity of the cathode 10, and thus improving the ion removal efficiency.

[0059] In this embodiment, the monitoring system 3 includes a water quality monitor, a potential monitor, and a flow rate monitor; Among them, the water quality monitor is used to monitor the concentration of iron, manganese and aluminum ions in seawater in real time. Spectrophotometer or ion chromatograph has high detection accuracy and can promptly report changes in water quality. Furthermore, water quality monitoring can use ion-selective electrodes or multi-parameter online water quality analyzers to monitor the ion concentration of iron, manganese and aluminum ions in real time. The potential monitor in monitoring system 3 can indirectly assess the potential environment of the aluminum alloy heat exchange tube bundle. The potential monitor tracks the potential changes of the anode 9 and cathode 10 to ensure that the electrodes operate within their normal potential range. Potential monitoring allows for assessment of the electrode reaction state and the system's operational stability. The flow monitoring device uses an electromagnetic flow meter or an ultrasonic flow meter to monitor the seawater flow rate in real time. By monitoring the flow rate, the residence time of seawater in the reactor is controlled to ensure the full progress of the ion exchange reaction. In this embodiment, the intelligent control system 4 includes a controller, a sensor module, and a data analysis module. The controller employs a programmable logic controller (PLC) to adjust the output parameters of the power supply system 2 in real time based on the data collected by the monitoring system 3. For example, when the water quality monitor detects an increase in the concentration of iron ions in seawater, the controller automatically increases the output current of the power supply to enhance the dissolution rate of the anode 9 and the reduction capacity of the cathode 10, thereby removing iron ions more effectively. The sensor module includes a water quality sensor, a potential sensor, and a flow sensor, which are responsible for collecting data on ion concentration, electrode potential, and seawater flow rate in seawater and transmitting them to the controller. The data analysis module analyzes and processes the data collected by the sensors to establish ion concentration change models and reaction efficiency models. By analyzing these models, the operating status and ion removal efficiency of the electrochemical ion exchange reactor 1 are predicted, providing a reference for adjusting the controller parameters.

[0060] In this embodiment, a closed-loop detection system is constructed through three dimensions: iron and manganese ion concentration detection, electrode potential detection, and anode 9 consumption monitoring. (1) The iron and manganese removal efficiency directly reflects the effectiveness of the electrode reaction, and its change is strongly correlated with the electron supply capacity (potential, activity) of anode 9 and the catalytic activity of cathode 10. (2) The potential state of anode 9 reflects its electron release activity, that is, its oxidation capacity, and the degree of consumption reflects the remaining electron supply capacity. Relationship judgment method: When the iron and manganese removal rate decreases, the potential of anode 9 and the consumption data are used to distinguish whether it is "anode 9 activity decay", "anode 9 capacity insufficiency" or "cathode 10 catalytic failure", thereby triggering the "external current compensation" or "anode 9 replacement" command.

[0061] I. Potential Correlation Detection and Calculation Method for Iron and Manganese Removal Efficiency (I) Core Computational Logic The iron and manganese removal efficiency is directly calculated using the "concentration difference between inlet and outlet," while the sufficiency of the reaction is verified by combining the "concentration at the midpoint of the reaction zone and the cathode potential," thus avoiding misjudgment based solely on inlet and outlet data. Formula for single ion removal rate: Single ion removal rate = [(inlet concentration - outlet concentration) / inlet concentration], that is: (Formula 1); Where, η X The single ion removal rate is X, where X represents iron or manganese ions, and C represents the single ion removal rate. xin For single ion inlet concentration, C xout This refers to the single-ion outlet concentration. Reaction sufficiency verification: When the concentration C at the midpoint of the reaction zone... xmid ≤0.3×C xinWhen C is constant, it indicates that the reaction proceeds uniformly along the spiral flow path; if C xmid >0.5×C xin If the cathode potential of the corresponding replacement chamber deviates from its exclusive optimal range (see the linkage analysis of each replacement chamber for the specific range), it is determined to be "abnormal potential regulation" and the state of the associated anode 9 needs to be adjusted.

[0062] (II) Analysis of the correlation between potential and removal efficiency The cathode potential is a "key regulatory signal" for the iron ion reduction reaction and the manganese ion reaction in the locally weakly alkaline region on the Ni-Co-P cathode surface. The weakly alkaline condition refers to a pH of 8-9. Its correlation with removal efficiency was experimentally calibrated, taking into account the reaction characteristics and specific potential ranges of each replacement chamber, as detailed below: First replacement chamber 6: Optimal range: cathode potential E cathode =+0.64V~+0.76V, at this point there is no hydrogen evolution side reaction, Fe 3+ It can achieve targeted priority restoration.

[0063] Abnormal range 1: E cathode > +0.76V, positive bias, Fe 3+ Insufficient thermodynamic driving force for reduction is mostly due to insufficient supply of 9 electrons to the anode (activity decay or positive potential shift). Abnormal range 2: E cathode <+0.64V, biased towards negative, prone to premature Fe triggering 2+ Restore, disrupt the step-by-step targeted restoration logic, η Fe3+ Although there is no significant decrease, it will lead to an increase in Fe in the subsequent second replacement chamber 7. 2+ To remove the increased load, the cathode potential needs to be adjusted upwards to return to the optimal range.

[0064] Second replacement chamber 7: Optimal range: cathode potential E cathode = -0.4V to -0.6V, at which point the hydrogen evolution side reaction accounts for <5%; Abnormal range 1: E cathode >-0.4V, biased positive, insufficient thermodynamic driving force for ferrous ion reduction, mostly due to insufficient supply of 9 electrons at the anode; Abnormal range 2: E cathode <-0.6V, slightly negative, hydrogen evolution reaction intensifies, η Fe The improvement is not significant, but the consumption of anode 9 is accelerated, and the current needs to be suppressed; Third replacement chamber 8: Optimal range: cathode potential E cathode =+0.435V~+0.565V, no hydrogen evolution side reaction, Mn 2+ It can be efficiently oxidized to MnO2 precipitate; Abnormal range 1: E cathode <0.435V, slightly negative, easily causing the newly formed MnO2 to undergo reverse reduction and dissolution; at the same time, the driving force for electric field migration is weakened, and the oxidation reaction of manganese ions is hindered, η Mn If the value decreases, the cathode potential needs to be adjusted upwards to return to the optimal range. Abnormal range 2: E cathode >0.565V, positive bias, the electrode polarization is too low, the catalytic oxidation reaction kinetics are insufficient, the MnO2 generation rate slows down and the conversion is insufficient, resulting in a decrease in manganese removal efficiency, mostly due to insufficient 9 electron supply at the anode.

[0065] By monitoring the cathode potential and iron / manganese removal rate in real time, the core reason for the inefficient reaction can be quickly identified: if η X Decrease and E cathode Positive bias → Anode 9-side problem; if η X Decrease and E cathode Negative bias → Cathode 10 side or flow field problem.

[0066] II. In-depth detection of the 9th state of the anode (dual dimensions of potential and consumption) (I) Anode 9-potential detection and activity assessment The potential of anode 9 directly reflects its electron release capability. It is necessary to compare the two potentials, "open circuit potential (OCP)" and "working potential (WCP)," to eliminate environmental interference. Potential reference value (anode 9 material is 5052 aluminum alloy, seawater condition); First replacement chamber 6: Initial open-circuit potential OCP0 = -1.55V to -1.60V (no oxide film on the surface, optimal activity, matching the spontaneous dissolution characteristics of the anode); The initial operating potential WCP0 is -1.55V to -1.60V (the anode in this replacement chamber maintains an open circuit potential, and electrons are supplied only through the galvanic cell reaction; the operating potential is consistent with the open circuit potential).

[0067] Second replacement chamber 7: Initial open-circuit potential OCP0 = -1.55V to -1.60V (optimal activity when there is no oxide film on the surface); The initial operating potential WCP0 is -1.50V to -1.58V (normal electron release state after forming a circuit with cathode 10).

[0068] Third replacement chamber 8: Initial open circuit potential OCP0 = -1.55V to -1.60V (the anode material is 5052 aluminum alloy, the initial open circuit potential is the same as other replacement chambers, only the working potential is adjusted according to the electron requirements); The initial operating potential WCP0 = -1.15V to -1.30V (after forming a circuit with cathode 10, it catalytically activates dissolved oxygen in the water to form superoxide radicals, Mn 2+ MnO2 is rapidly generated by losing electrons under locally weakly alkaline conditions, where the weakly alkaline conditions refer to a pH of 8-9.

[0069] Matched with the standard electrode potential for the reaction of anode 9.

[0070] The pattern of potential changes and the judgment logic are shown in Table 1: Table 1. Potential Change Patterns and Judgment Logic

[0071] The positive shift in the anode potential at point 9 is essentially due to "increased resistance to electron release," meaning either a high-resistivity oxide film forms on the surface. (Aluminum ions hydrolyze to form Al(OH)3 gel), or the slime prevents the anode 9 from contacting the seawater. The difference between OCP and WCP can be used to distinguish between them: if OCP is normal but WCP is positive → slime or oxide film (surface problem); if both OCP and WCP are positive → anode 9 is consumed or its activity is reduced (internal problem).

[0072] (II) Anode 9 Consumption Level Detection and Remaining Life Prediction The thickness of the spiral aluminum alloy anode 9 cannot be directly measured along its entire length. This solution employs a dual verification method of direct thickness detection and dissolution rate calculation to ensure accurate consumption assessment.

[0073] Direct thickness measurement: Select the inlet, middle section and outlet of the anode 9 spiral to install test samples and measure the remaining thickness h of anode 9 (initial thickness h0=20mm).

[0074] The formula for calculating the remaining capacity factor k is as follows: (Formula 2); Dissolution rate calculation: Based on Faraday's law: Faraday's First Law: The mass m (in grams) of the substance dissolved at an electrode is directly proportional to the total charge Q (in cubic centimeters) passing through the electrode, that is: (Formula 3); (K is the electrochemical equivalent, which is related to the type of substance); Faraday's Second Law: (Formula 4); (M is the molar mass of the substance, n is the number of electrons transferred, and F is the Faraday constant); Total battery power: (Formula 5); (I is the average current of the anode 9 circuit, in A; t is the energizing time, in s).

[0075] Step 1: Calculate the mass m of anode 9 dissolved: Based on the above laws, the formula for the mass of dissolution is: (Formula 6); Where η (current efficiency, 0.9~0.95): In actual working conditions, in addition to the main reaction in which aluminum atoms lose 3 electrons to generate aluminum ions, a small amount of hydrogen evolution side reaction may occur at anode 9. Therefore, the current efficiency is used to correct the proportion of the amount of electricity that effectively participates in the dissolution reaction (the default value is η=0.92, which can be calibrated experimentally).

[0076] Step 2: Calculate the volume of dissolution, V: According to the density formula: (Formula 7); The volume of solution obtained by deformation: (Formula 8); Units for parameters are consistent: ρ = 2.68 g / cm³ 3 (Density of aluminum alloy), M = 27 g / mol, therefore the unit of V is cm. 3 .

[0077] Step 3: Calculate the thickness Δh of the dissolved material: The dissolution of anode 9 is uniform corrosion (ideal state), and the dissolution volume is equal to "effective reaction area × dissolution thickness", that is: (Formula 9); Transformed to: (Formula 10); Step 4: Calculate the dissolution rate and convert the dissolution rate v to mm / month: (1) The dissolution rate v is defined as "the thickness of dissolution per unit time", so: (Formula 11); (2) The unit for converting the dissolution rate v is mm / month: Key points for unit conversion: The effective reaction area of ​​anode 9 is S = 0.5 m². 2 =0.5×10 4 cm 2 (1m) 2 =10 4 cm 2 ); The dissolution thickness Δh is in cm and needs to be converted to mm (1cm=10mm).

[0078] The unit of time t needs to be converted from "seconds" to "months" (1 month ≈ 30 days × 24 hours × 3600 seconds = 2.592 × 10). 6 s), we get: Definition of dissolution rate: (Formula 12); (Formula 13); Step 5: Substitute the parameters to simplify the formula: Given the parameters (M=27, n=3, F=96500, ρ=2.68, S=0.5×10), 4 Substituting η=0.92, we calculate the constant term: constant term = [27×0.92×10×(2.592×10 6 )] / [(3×96500×2.68×(0.5×10 4 )]≈0.166; Final simplified formula for engineering applications: (Formula 14); The dissolution rate v is measured in mm / month. When the current I is measured in A, the dissolution rate can be calculated directly and quickly (e.g., when I = 5A, v ≈ 0.166 × 5 = 0.83 mm / month; in actual operating conditions, the current fluctuations need to be taken as the average value).

[0079] By combining the real-time current I, the remaining life T (months) of anode 9 can be dynamically calculated: (Formula 15); (h) min =3mm, minimum safe thickness, to avoid exposing the anode 9 support structure). The relative solubility coefficient k1' is derived based on the remaining capacity coefficient k: Where: Δh 累计 =h0−h (cumulative dissolved thickness, mm); h0 is the initial thickness; h is the remaining thickness, obtained by direct detection; k (remaining capacity coefficient) = h / h0; (Formula 16); The relative solubility coefficient k2' is derived based on the dissolution rate: Meanwhile, the cumulative dissolved thickness is also: (Formula 17); (T) 使用 Given that anode 9 has been in operation for [number] months, the relative solubility coefficient k2′ is derived based on the dissolution rate v. (Formula 18); Dual verification logic: The relative solubility coefficient k1' derived from the remaining capacity coefficient k is compared with the relative solubility coefficient k2' derived from the dissolution rate to verify the consistency of the data. If the deviation between the two is ≤ ±5%, it indicates that the consumption assessment is accurate, and the relative solubility coefficient k' adopts the average of the two. If the deviation is > 5%, the cause should be investigated (such as fluctuations in current efficiency η, local corrosion causing the directly tested sample to be unrepresentative, current measurement error, etc.).

[0080] The lifetime intervals based on k and k' are shown in Table 2: Table 2. Lifetime interval division based on k and k'

[0081] The uneven consumption of anode 9 is a key issue in the spiral structure. The strong water flow at the inlet leads to a 15%–20% higher dissolution rate than at the outlet, causing anode 9 in a certain coaxial spiral nested component to fail first. By using multi-point thickness detection and dissolution rate calculation, the "weak point" can be located, allowing for the replacement of anode 9 only in a single coaxial spiral nested component, rather than replacing all anode 9 in the entire coaxial spiral nested module, thus reducing maintenance costs.

[0082] It should be noted that while formula 14 in the instruction manual, v≈0.166I, is derived from theoretical formulas, in practice, the dissolution rate v is not a fixed value. Instead, it dynamically changes based on current density, seawater flow rate, corrosive environmental conditions, and the state of the oxide film on the anode 9 surface. The remaining lifespan T directly depends on the value of v. Therefore, different operating conditions result in different dissolution rates v, leading to differences in the corresponding remaining lifespan T. This difference is the discrepancy between theory and practice. In actual use, a single anode 9 is typically replaced approximately every year, with an overall replacement cycle of 3-4 years (including anode replacement). This varies slightly depending on the equipment's commissioning time and the volume of water treated, but generally, a 3-4 year maintenance and replacement cycle is considered a standard procedure.

[0083] It should be noted that electrodes are installed inside the first, second, and third replacement chambers, with different potentials set for each electrode to perform independent electrochemical treatment of iron and manganese ions. Utilizing the difference in standard electrode potentials for the redox reactions of different ions, and through intelligent staged control of the cathode potential, combined with the kinetic optimization of the Ni-Co-P catalytic layer on cathode 10, stepwise reduction of ferric ions to ferrous ions, and then from ferrous ions to elemental iron, as well as the reduction of Mn... 2+ The process involves a staged reaction of oxidation to generate MnO2, followed by removal through flocculation and co-precipitation. Simultaneously, through synergistic control of anodic potential and design to suppress side reactions, the electrochemical oxidation-reduction-catalytic adsorption synergistic process is ensured to be efficient and controllable.

[0084] III. Circuit Optimization: (a) Optimized circuit for iron ion reduction potential: The iron ion reduction potential optimization circuit targets "Fe 3+ →Fe 2+ "Fe" 2+ To address the differentiated requirements of the two-step reaction for Fe element, a step-by-step closed-loop control design is adopted, as detailed below: Reduction peak potential (Epc) determination: Cyclic voltammetry (scan rate 50 mV / s, potential window -1.0 V to +1.0 V) was used to determine the reduction peak potentials of the two-step reaction on the surface of the Ni-Co-P catalytic cathode: Fe 3+ →Fe 2+ The reduction peak potential (Epc1) of Fe is +0.65V to +0.75V (close to the standard reduction potential of +0.77V). 2+ →Reduction peak potential (Epc2) of Fe element: -0.50V to -0.60V (close to the standard reduction potential of -0.44V).

[0085] Step-by-step constant potential control: First replacement chamber 6 (Fe) 3+ →Fe 2+ When the original potential does not meet the reaction requirements, the cathode potential is mainly stabilized at Epc1±10mV (+0.64V~+0.76V) by the PID controller. This range is negative for Fe. 3+ / Fe 2+ The standard reduction potential satisfies the thermodynamic criterion of "cathode potential ≤ ion standard reduction potential", ensuring Fe 3+ It preferentially reduces hydrogen evolution; at the same time, this potential range differs significantly from the standard reduction potential of the hydrogen evolution reaction, and is far positive than the initiation potential threshold of the hydrogen evolution reaction, thus thermodynamically completely suppressing the occurrence of hydrogen evolution side reactions.

[0086] Second replacement chamber 7 (Fe) 2+ →Elemental Fe): The cathode potential is stabilized at Epc2±10mV (-0.51V to -0.61V) using a PID controller. This range is negative for Fe. 2+ The Fe standard reduction potential is satisfied with the thermodynamic requirements and is controlled within the optimal range (-0.4V to -0.6V) where the proportion of hydrogen evolution side reaction is <5%.

[0087] Closed-loop control mechanism: Real-time linkage between the circuit and the monitoring system's potential sensor and water quality sensor: The potential sensor collects the real-time cathode potential; when it deviates from the set range by ±5mV, the PID controller dynamically adjusts the output potential with a response time ≤100ms; the water quality sensor monitors the Fe at the inlet and outlet of the replacement chamber. 3+ Fe2+ Concentration triggers coordinated adjustment of the anode potential (e.g., reducing the anode operating potential by 0.02V to 0.03V) to enhance electron supply.

[0088] (II) Optimization of the environmental potential for manganese ion flocculation and precipitation: For Mn 2+ Oxidative flocculation and precipitation characteristics, using "Fe 2+ The design incorporates a "mild pre-oxidation process to regulate the aquatic microenvironment, a Ni-Co-P catalytic layer to efficiently activate dissolved oxygen in the water, pulsed potential regulation, and Al(OH)3 flocs to capture and precipitate" as follows: Preprocessing-mediated mechanism: Third replacement chamber 8 (Mn) 2+ →MnO2→flocculation and precipitation): The inlet water in the third replacement chamber 8 carries the Fe generated in the previous reaction. 2+ By introducing a small amount of air into the replacement chamber, the Fe... 2+ The oxidation reaction; simultaneously, the 2% Ru doped in the Ni-Co-P catalyst layer can catalyze the activation of dissolved oxygen to generate highly active O2. - This reactive oxygen species will Mn 2+ Efficient oxidation to MnO2, while Al at the anode 3+ In a weakly alkaline environment, a network of Al(OH)3 flocs is generated, which captures MnO2 to form a complex co-precipitate.

[0089] Manganese oxidation characteristic potential (Epc) Mn Interval determination: Cyclic voltammetry (scan rate 50 mV / s, potential window 0.2 V to +0.8 V) was used, combined with MnO2 / Mn 2+ The corresponding redox characteristics of Mn were used to determine 2+ The optimal characteristic potential range for efficient oxidation to MnO2 is +0.45V to +0.55V.

[0090] Pulse constant potential control: Control objective: Based on the characteristic potential of manganese oxidation, the optimal control range for the cathode is set to +0.435V to +0.565V to match a weakly polarized electric field environment. This satisfies the thermodynamic and kinetic requirements of manganese catalytic oxidation while avoiding insufficient oxidation kinetics due to a positive potential bias and reverse reduction of MnO2 due to a negative potential bias. Pulsed potential mode operation (duty cycle 1:5, frequency 100Hz) is adopted. Intermittent electric field output can shorten the duration of strong polarization and effectively suppress residual Fe. 3+ Competitive reduction and weakening of interfacial polarization enrichment effects keep the proportion of cathode hydrogen evolution side reactions below 5%.

[0091] Matching PID dynamic closed-loop control: Real-time acquisition of cathode current density and linkage correction of pulse potential peak value, when current density > 12 A / m2 The analysis indicated that the competitive reduction of iron ions was intensified, leading to a decrease in the peak potential by 0.02V, thus weakening the cathode's reduction capability. When the current density was <8 A / m... 2 The reaction was determined to be due to insufficient kinetic energy in the manganese oxidation reaction. The peak potential was increased by 0.01V to enhance electric field migration and catalytic oxidation efficiency.

[0092] (III) Coordinated control mechanism of anode and cathode potentials The potential optimization for both iron and manganese ions is based on a synergistic control logic with the working potential (WCP) of the anode, ensuring a reasonable overall potential difference and efficient reaction. Cooperative control logic (such as) Figure 6 (as shown) First replacement chamber 6 (Fe) 3+ →Fe 2+ The anode working potential is maintained at -1.55V to -1.60V, forming a potential difference of 2.24V to 2.31V with the cathode potential (+0.64V to +0.76V), which satisfies the low electron requirement while avoiding excessive dissolution of the anode. Second replacement chamber 7 (Fe) 2+ →Elemental Fe): The anode working potential is adjusted to -1.50V to -1.58V, forming a potential difference of 0.97V to 0.99V with the cathode potential (-0.51V to -0.61V), thus balancing the reaction efficiency and anode stability; The third replacement chamber 8 (Mn species-oriented transformation): The anode working potential is adjusted to -1.15V to -1.30V, forming a potential difference of 1.715V to 1.735V with the cathode potential of +0.435V to +0.565V. This provides sufficient thermodynamic drive for the directional transformation and flocculation precipitation reaction of MnO2 in the system, while ensuring the stable dissolution of aluminum ions and synergistically achieving efficient removal of manganese ions. Linkage control trigger: When the cathode potential deviates from the set range of ±5mV for 30s, the intelligent control system 4 first makes small adjustments to the anode potential within the inherent stable potential range of the anode in the corresponding chamber (±0.02V each time). When the anode potential has reached the upper or lower limit of the chamber range, or when the cathode potential has not returned to the set range after the adjustment, the cathode potential is then finely adjusted. The anodes of each chamber are strictly limited to their respective preset working ranges: the first replacement chamber 6 (−1.55V~−1.60V), the second replacement chamber 7 (−1.50V~−1.58V), and the third replacement chamber 8 (−1.15V~−1.30V), maintaining the established potential difference and the thermodynamic conditions of the graded reaction in each chamber.

[0093] IV. Electrode control strategy (which involves external current compensation and anode 9 replacement prompts), as follows: (a) External current compensation mechanism 1. Compensation trigger condition (meeting any one of the following): The remaining capacity coefficient k of anode 9 is less than or equal to 0.2 (or the remaining lifespan T is less than or equal to 2 months). The electron supply capacity of the anode dissolution is reduced, which cannot meet the power demand for iron ion reduction. When the anode working potential is greater than the upper limit of the range, the activity decreases and cannot be returned to the stable range by fine-tuning the anode potential within 24 hours. Potential E of composite catalytic cathode (10) cathode When the optimal operating range is exceeded, scale or activity decay occurs on the cathode surface. Even after ultrasonic cleaning, the abnormal potential does not improve, and the iron ion reduction and manganese ion oxidation precipitation conditions become unstable.

[0094] 2. Compensation current design (dynamically adjustable to avoid hydrogen evolution side reactions): Compensation power supply: Turn on power system 2, low voltage DC auxiliary power supply (output voltage 0~5V, current 0~20A), positive terminal connected to the collector busbar in collector box 12, negative terminal connected to fixed shaft 14 (forming "dual electron supply" with anode 9), to supplement electrons for the reduction reaction of iron ions at cathode; Current regulation logic: Compensation current I compensate The "electronic supply and demand balance" constraint must be met, namely: (Formula 19); I anode (t) represents the spontaneous dissolution current (A) at time t, derived from I anode =FvS Derivation (v is the anolyte dissolution rate (in m / s), S is the effective anolyte area (in m²) 2 (where F is the Faraday constant). in: (Formula 20); (n) Fe n represents the number of electrons transferred by the iron ion; Mn n represents the number of electrons transferred by the manganese ion. Fe =3, Fe 3+ →Fe 2+ →Fe gains 3e - ;n Mn =2,Mn 2+ →MnO2 loses 2e - Q represents seawater flow rate (unit: m³ / s). 3 / h); C Fein Iron ion inlet concentration (unit: mol / m³) 3 ); C Mnin Manganese ion inlet concentration (unit: mol / m³) 3 ); =Electron utilization efficiency, taken as 0.95). Irequired (t) is the minimum current (A) required for the iron-manganese redox reaction at time t, calculated using formula 20: I required =FQ(n Fe C Fein- n Mn C Mnin ) / 3600η e Constraints: The cathode potential E must be monitored in real time during the compensation process. cathode And maintain it within the optimal operating range; if the cathode potential is higher than the upper limit of the optimal range, it indicates that the electron supply is excessive, and I is gradually reduced by 5% at a time. compensate The cathode potential is increased until it returns to the optimal range, suppressing the hydrogen evolution side reaction. If the cathode potential is lower than the lower limit of the optimal range, it indicates insufficient electron supply. The compensation current is gradually increased to pull the anode back to the activation region of -1.6 to 1.65V, restoring aluminum ion dissolution and ensuring the normal progress of the iron and manganese ion precipitation reaction.

[0095] 3. Verification of compensation effect: After compensation is initiated, monitor in real time: ①η Fe ≥88%, η Mn ≥82% (target value); ② Anode working potential WCP returns to the stable range; ③ Cathode potential E cathode The current compensation current is maintained within the optimal range if all three conditions are met simultaneously; otherwise, it is dynamically adjusted.

[0096] (II) Anode 9 Replacement Prompt and Execution Mechanism 1. Change the trigger condition (meeting any of the following): The residual capacity coefficient k of anode 9 is less than 0.15 or the relative solubility coefficient k' of anode 9 is greater than 0.85; Remaining lifespan T < 0 (safe thickness exceeded); If the anode working potential WCP remains above the upper limit of the range for more than 24 hours, and the potential still cannot return to the stable range after fine-tuning the anode working potential through the intelligent control system, it is determined that the anode activity has completely decayed. The magnetostrictive sensor detected that the local thickness of anode 9 is ≤3mm (minimum safe thickness), which poses a risk of structural fracture.

[0097] 2. Change prompts and execution process: (1) Early warning stage (0.15≤k<0.2 or 0.8<k'≤0.85): The system issues an "Anode 9 replacement warning", displays the remaining lifespan and the optimal replacement window (avoiding the period of high seawater turbidity), and simultaneously pushes a spare parts procurement reminder; (2) Emergency alert stage (k < 0.15 or k' > 0.85): The system issues an audible and visual alarm, locks the "replacement priority", and displays the anode 9 that needs to be replaced (based on multi-point detection to locate weak points). (3) Replacement execution: The anode storage chamber 11 stores 3 to 4 new anodes 9 in layers, which can realize the automatic replacement of anodes 9 first. When all the new anodes 9 stored in the anode storage chamber 11 are used up, new anodes 9 are manually added to the anode storage chamber 11.

[0098] In this embodiment, the automatic replacement process of anode 9 is as follows: The anode storage chamber 11 stores 3 to 4 new anodes 9 stacked together. The telescopic controller 13 located above the new anodes 9 can independently or interlock the process of the intelligent control system 4 to carry out the online replacement operation of the anodes 9 in the anode storage chamber 11 through the steps of axial compression, limit fixation, and extension.

[0099] Specifically, when the intelligent control system 4 determines that the entire anode 9 needs to be replaced through potential monitoring and thickness detection, the process is automatically initiated: First, the front gate is closed to isolate the flow channel on the replacement chamber side where the anode to be replaced (old anode 9) is located, while the rear gate remains open to form a valve cavity; then, the residual seawater in the replacement chamber where the anode to be replaced 9 is located is emptied and the pressure is balanced to ensure that there is no risk of leakage during operation; finally, the axial fixation of the old anode 9 is released, and its conductive connection with the current collector box 12 is disconnected. After the conductive connection is disconnected, the current collector box 12 automatically switches to the "standby insulation state" to prevent short-circuit current from being generated due to accidental contact during the replacement process. A retaining ring is provided at one end of the anode storage chamber 11 away from the telescopic controller 13. This ring is used to prevent the new anode 9 from being compressed and deformed by external force when the anode storage chamber 11 moves downward to replace the new anode 9. A fixing groove is provided at the other end to fix the new anode 9. The fixing shaft 14 is an axial sliding support mechanism for the new anode 9. A limiting locking pin 15 is provided at the bottom of the fixing shaft 14 to engage with the anode 9. A locking through hole is provided at one end of the anode 9 to engage with the limiting locking pin 15. The telescopic controller 13 is connected to the top of the anode storage chamber 11. When the telescopic controller 13 extends axially, it pushes the anode storage chamber 11 to the position of the limit locking pin 15. The snap-fit ​​hole on the new anode 9 in the anode storage chamber 11 engages with the limit locking pin 15, fixing one end of the new anode 9. At the same time, during the pushing process, the old anode 9 is compressed downward to the limit locking pin 15 and disengaged from the limit locking pin 15, causing the old anode 9 to be compressed below the limit locking pin 15. When the telescopic controller 13 retracts, it brings the anode storage chamber 11 back to its original position. Under the pull of external force, the new anode 9 deforms and disengages from the limiting effect of the fixing groove. At the same time, the new anode 9, which is engaged with the limit locking pin 15, loses the external force from the anode storage chamber 11 and recovers its spiral structure under the action of elastic deformation force, that is, it extends upward along the fixed axis 14, completing the replacement process of the anode 9. The replacement process employs both mechanical positioning and electrical performance verification to ensure the operational stability of anode 9. After the new anode 9 reaches the preset position, the limiting locking pin 15 of the fixed shaft 14 pops out to achieve axial fixation. The intelligent control system 4 initiates a small current test to detect the potential difference of each spiral segment of the new anode 9, ensuring uniform current distribution. Subsequently, the elastic conductive end of the current collector box 12 automatically pops out and tightly connects with the conductive connector of the new anode 9, restoring circuit continuity. At this point, the automatic replacement process of anode 9 is complete. The old anode 9, compressed below the limiting locking pin 15, continues to contact with seawater as an auxiliary anode 9 and participates in the reaction, gradually corroding and breaking off from the coaxial spiral nested structure assembly, and finally being intercepted and discharged through the filter element of the filter chamber 16.

[0100] In this embodiment, the process of manually replenishing the new anode 9 to the anode storage chamber 11 is as follows: Manual replenishment applies to the first, second, and third replacement chambers. The top of the electrochemical ion exchange reactor 1, the sidewall of the second replacement chamber 7, and the sidewall of the third replacement chamber 8 can be opened and closed. If the coaxial spiral nested structure assembly in the first replacement chamber 6 needs to be replenished with new anode 9 to the anode storage chamber 11, the electrochemical ion exchange reactor 1 can be opened from the top to replenish the anode storage chamber 11 with new anode 9. If the coaxial spiral nested structure assembly in the second replacement chamber 7 needs to be replenished with new anode 9 to the anode storage chamber 11, the electrochemical ion exchange reactor 1 can be opened from the sidewall of the second replacement chamber 7 to replenish the anode storage chamber 11 with new anode 9. If the coaxial spiral nested structure assembly in the third replacement chamber 8 needs to be replenished with new anode 9 to the anode storage chamber 11, the electrochemical ion exchange reactor 1 can be opened from the sidewall of the second replacement chamber 7 to replenish the anode storage chamber 11 with new anode 9. When a new anode 9 needs to be added to the anode storage chamber 11, the electrochemical ion exchange reactor 1 can be opened from the side wall of the third replacement chamber 8 to add the new anode 9 to the anode storage chamber 11 (replacement time < 30 minutes; the first replacement chamber 6, the second replacement chamber 7, and the third replacement chamber 8 do not require simultaneous manual replenishment of the new anode 9 to the anode storage chamber 11; if one of them is in use, there is no need to shut down the entire reactor, only the corresponding flow channel is closed); the top of the electrochemical ion exchange reactor 1, the side wall of the second replacement chamber 7, and the side wall of the third replacement chamber 8 are all equipped with quick-sealing flanges and transparent observation windows, and the coaxial spiral nested structure assembly is equipped with independent positioning pins and conductive joints.

[0101] Specifically, the intelligent control system 4 closes the inlet and outlet valves of the flow channel corresponding to the replacement chamber where the coaxial spiral nested structure component of the new anode 9 is located, cutting off the seawater flow to that chamber; it opens the flow channel pressure relief valve and exhaust valve, and closes them after the pressure drops to atmospheric pressure; a detachable coaxial spiral nested structure module is installed inside the quick-sealing flange, and the spiral nested structure module is precisely matched with the mechanical limit sliders on the side walls of the first replacement chamber 6, the second replacement chamber 7, and the third replacement chamber 8. At the same time, the positioning reference line is projected through the perspective observation window alignment device to ensure accurate insertion and removal direction; if the replacement chamber where the coaxial spiral nested structure component of the new anode 9 is located is the first replacement chamber 6, the quick-sealing flange on the top of the ion exchange reactor 1 is opened; if the replacement chamber where the coaxial spiral nested structure component of the new anode 9 is located is the second replacement chamber 7 or the third replacement chamber 8, the quick-sealing flange on the side wall of the replacement chamber is opened. Rotate the coaxial spiral nested structure module until the coaxial spiral nested structure assembly containing the new anode 9 is rotated to the sealing flange and the viewing window. Insert a special wrench through the top (if the replacement chamber containing the coaxial spiral nested structure assembly containing the new anode 9 is the first replacement chamber 6) or side wall (if the replacement chamber containing the coaxial spiral nested structure assembly containing the new anode 9 is the second replacement chamber 7 or the third replacement chamber 8) of the ion exchange reactor 1. Sequentially remove the current collector box 12 and the telescopic controller 13. Fill the upper cover of the anode storage chamber 11 with the new anode 9, then reinstall the telescopic controller 13 and the current collector box 12. Next, close the quick-sealing flange, close the flow channel pressure relief valve, and open the exhaust valve. Open the inlet and outlet valves of the flow channel corresponding to the replacement chamber containing the coaxial spiral nested structure assembly containing the new anode 9 to connect the seawater flow in that chamber, completing the manual replenishment of the new anode 9 to the anode storage chamber 11. The automatic replacement process of the anode 9 can then continue.

[0102] (4) Calibration after replacement: After the new anode 9 is installed, check whether OCP and WCP have returned to their initial values, reset the remaining life calculation model synchronously, and start the initial operation (reduce the flow rate by 30% for the first 24 hours to avoid excessive flushing of anode 9).

[0103] It should be noted that when the iron and manganese elemental layers completely cover the Ni-Co-P catalyst layer of the cathode 10, and the catalyst layer of the cathode 10 is deactivated, it needs to be cleaned. For example, it can be cleaned by using a cleaning brush after opening the ion exchange reactor 1 during the process of manually replenishing the new anode 9 to the anode storage chamber 11.

[0104] Figure 5This is an embodiment of a nested structure of a first replacement chamber 6, a second replacement chamber 7, and a third replacement chamber 8. The first replacement chamber 6 is cylindrical, including a chamber wall, a top cover on the upper part of the chamber wall with a water inlet channel, and a bottom on the lower part of the chamber wall. A water outlet channel is located on the bottom near the chamber wall, allowing seawater to enter the second replacement chamber 7 close to the chamber wall. This ensures sufficient contact between the seawater and the electrode assembly. A boss structure is provided on the circumference of the bottom, allowing the boss of the first replacement chamber 6 to be embedded into the inner side of the chamber wall of the second replacement chamber 7 with an interference fit. At the same time, the bottom of the first replacement chamber 6 also becomes the top cover of the second replacement chamber 7. This nested structure is also used between the second replacement chamber 7 and the third replacement chamber 8. An air inlet channel is opened in the water outlet channel at the bottom of the second replacement chamber 7, which can introduce air or oxygen into the water outlet channel, so that the seawater mixes with the air or oxygen and flows into the third replacement chamber 8. The air inlet channel can be made of plastic pipe, which can form a circular channel. This channel surrounds the water outlet channel and is covered with small air outlet holes. The air pump blows air or oxygen into the air inlet channel, into the circular channel, and then out through the small holes and mixes with the seawater.

[0105] V. The intrinsic relationship between anode 9 consumption and potential, and the diagnosis of abnormalities (I) The consumption-potential linkage law of anode 9 (core mechanism) The "consumption-potential" relationship of anode 9 exhibits a non-linear change, which can be divided into three stages: Initial stage (0-3 months, k=1.0-0.8): There is no oxide film on the surface of anode 9, WCP is stable at -1.58V to -1.5V, and the dissolution rate v is uniform (v≈0.8-1.0mm / month). At this time, consumption is weakly correlated with potential (potential remains basically unchanged, and consumption is uniform). Mid-term stage (3-8 months, k=0.8-0.3): A thin oxide film forms on the surface, the WCP gradually shifts positive (for every 1 mm of thickness consumed, the potential shifts positively by ≈0.05 V), the dissolution rate v decreases slightly (v≈0.6-0.8 mm / month), at this time the consumption and potential are strongly positively correlated (the more it is consumed, the more positive the potential). In the final stage (8-10 months, k=0.3-0.15): the oxide film thickens and detaches locally, the WCP fluctuation increases (±0.08v), the dissolution rate v accelerates (v≈1.2-1.5mm / month, caused by local scouring and oxide film detachment), and at this time the correlation between consumption and potential decreases (potential shifts positively but consumption is uneven).

[0106] In the intermediate stage, the consumption level can be directly estimated by potential (error < 5%). In the initial and final stages, thickness detection is required for correction to avoid misjudgment based on a single potential indicator.

[0107] This embodiment is fully compatible with the reaction chamber 5 structure of "outer spiral aluminum alloy anode 9 and inner stainless steel cathode 10". Through in-depth correlation analysis of potential detection, it realizes real-time monitoring and closed-loop control of iron and manganese removal efficiency and anode 9 status, solving the core pain points of traditional sacrificial anode 9 system: "difficult to judge status, replacement based on experience, and easy efficiency decay".

[0108] VI. Ensure the accuracy and operability of the consumption assessment for aluminum alloy anodes. Calibration method for current efficiency η: Periodically calibrated by the "weighing method". Select a sample of the same material and size as anode 9, run it under actual operating current for a certain period of time, weigh it, and calculate the actual dissolved mass m. 实测 , with theoretical dissolution mass m 理论 .

[0109] Theoretical dissolution mass m 理论 Calculation formula; (Formula 21); In comparison, (Formula 22); It is calibrated every 6 months.

[0110] Dynamic correction of dissolution rate: When changes in seawater temperature and salinity cause fluctuations in current I, the "moving average method" (taking the average current over the past 72 hours) is used to calculate v, thereby improving the accuracy of remaining lifetime prediction.

[0111] The collaborative verification logic of k and k' is as follows: In daily operation, v and t, which are indirectly calculated, are used for dynamic early warning, and k, which is calculated by directly detecting the thickness, is used as the final judgment basis; when k enters the early warning range, the replacement time is planned based on the direct detection data.

[0112] This embodiment, through the above derivation, realizes a complete logical chain between absolute dissolution rate v, relative dissolution coefficient k', and remaining life T, and is deeply linked with direct thickness detection data to ensure the accuracy and operability of aluminum alloy anode 9 consumption assessment.

[0113] To further enhance understanding of this application, this application also provides a coaxial spiral anode replacement device and method for the protection of low-temperature multi-effect seawater desalination, which is compatible with the aforementioned potential compensation device for protecting low-temperature multi-effect seawater desalination devices. The method includes the following steps: 1. Seawater pretreatment: The seawater first undergoes conventional pretreatment processes, such as filtration and sedimentation, to remove large particulate impurities and suspended solids in the seawater, so as to reduce the impact on the electrochemical ion exchange reactor 1.

[0114] 2. Electrochemical ion exchange reaction: Pretreated seawater enters the reaction chamber 5 of the electrochemical ion exchange reactor 1. Under the action of the DC electric field provided by the power supply system 2, the anode 9 undergoes an oxidation reaction, loses electrons and dissolves to produce aluminum ions; the cathode 10 receives electrons, causing iron ions in the seawater to undergo a reduction reaction on the cathode surface to produce elemental iron. Manganese ions are oxidized by dissolved oxygen under the local weak alkaline conditions of the cathode, and are converted into oxide precipitates. The weak alkaline conditions refer to a pH of 8-9. Deposition is achieved through the flocculation effect of aluminum ion hydrolysis products.

[0115] 3. Real-time monitoring and control: The monitoring system 3 monitors the ion concentration, electrode potential, and seawater flow rate parameters in seawater in real time and transmits the data to the intelligent control system 4. The intelligent control system 4 adjusts the output parameters of the power supply system 2 in real time based on this data to ensure the stable operation of the electrochemical ion exchange reactor 1 and the ion removal effect.

[0116] 4. Seawater discharge after treatment: The seawater, after electrochemical ion exchange treatment, flows out from reaction chamber 5 and enters the subsequent seawater desalination process. At this point, the content of iron and manganese ions in the seawater has been significantly reduced, effectively preventing corrosion of the aluminum alloy heat exchange tube bundle.

[0117] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. This application is not limited to the exact structures described above and illustrated in the accompanying drawings, and it should not be considered that the specific implementation of this application is limited to these descriptions. For those skilled in the art, various changes and modifications made without departing from the concept of this application should be considered to fall within the protection scope of this application.

Claims

1. A coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection, characterized in that, It includes an electrochemical ion exchange reactor (1), a monitoring system (3) and an intelligent control system (4). The electrochemical ion exchange reactor (1) includes a reaction chamber (5), and the reaction chamber (5) includes at least one displacement chamber. The displacement chamber is provided with a coaxial spiral nested structure assembly. The replacement chamber is equipped with a front gate at the front end in the direction of coastal water flow and a rear gate at the rear end in the direction of coastal water flow. The replacement chamber is also connected to a drainage pressure balancing channel for draining residual seawater and balancing pressure. The coaxial spiral nested structure assembly includes an outer spiral anode (9), an inner spiral cathode (10), an anode storage chamber (11), a current collector (12), a telescopic controller (13), a fixed shaft (14), and a limit locking pin (15). The outer spiral anode (9) is coaxially arranged around the inner spiral cathode (10), and the spiral parameters of the outer spiral anode (9) and the inner spiral cathode (10) are matched to form a spiral electrochemical reaction channel for seawater flow between them. The fixed shaft (14) is coaxially engaged with the inner spiral cathode (10) to provide coaxial positioning and axial support for the inner spiral cathode (10), and to serve as an axial sliding support mechanism when the spare anode enters the working position; the limiting locking pin (15) is located at the bottom of the fixed shaft (14) and is used to engage with the snap-fit ​​hole on the anode (9). The anode storage chamber (11) is used to store spare anodes. The telescopic controller (13) is connected to the top of the anode storage chamber (11). A retaining ring is provided at one end of the anode storage chamber (11) away from the telescopic controller (13), and a fixing groove for fixing spare anodes is provided at the other end. The telescopic controller (13) is used to drive the anode storage chamber (11) to move axially along the fixed shaft (14), so that the spare anode is engaged with the limiting locking pin (15) through the snap-fit ​​hole, and when the telescopic controller (13) retracts, the spare anode is released and extended along the fixed shaft (14) to the working position coaxially nested with the inner spiral cathode (10). The current collector (12) is provided with an elastic conductive end, the outer spiral anode (9) and / or the spare anode are provided with conductive connectors, the current collector (12) has a spare insulation state for disconnecting the conductive connection, and the elastic conductive end is used to connect with the conductive connector after the spare anode enters the working position and completes the limiting fixation, so that the spare anode is connected to the electrochemical reaction circuit; The monitoring system (3) is used to detect the potential state or consumption state of the anode (9), and the intelligent control system (4) is used to control the front gate, the drainage pressure balance channel, the telescopic controller (13) and the collector box (12) to perform anode replacement according to the detection result of the monitoring system (3).

2. The coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to claim 1, characterized in that, The intelligent control system (4) is used to control the front gate to close to isolate the water inlet channel of the replacement chamber where the anode to be replaced is located when it is determined that the anode to be replaced meets the replacement conditions, and to keep the rear gate open to form a valve cavity between the front gate and the rear gate.

3. The coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to claim 1, characterized in that, The outer spiral anode (9) is a spiral corrugated plate aluminum alloy anode, and the inner spiral cathode (10) is a spiral corrugated plate cathode. The pitch, diameter and direction of the outer spiral anode (9) and the inner spiral cathode (10) are matched so that the spiral electrochemical reaction channel extends continuously along the axial direction of the fixed shaft (14).

4. The coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to claim 1, characterized in that, The inner spiral cathode (10) is provided with a central hole and a limiting groove that cooperate with the fixed shaft (14). The fixed shaft (14) cooperates with the central hole, and the limiting locking pin (15) cooperates with the limiting groove to limit the radial displacement of the inner spiral cathode (10) relative to the outer spiral anode (9).

5. The coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to claim 1, characterized in that, Multiple spare anodes are stacked in the anode storage chamber (11), and a partition plate is provided between adjacent spare anodes; the retaining ring is used to limit the axial compression of the spare anodes during the axial movement of the anode storage chamber (11), and the fixing groove is used to temporarily fix the spare anodes before they are put into service.

6. The coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to claim 5, characterized in that, The spare anode is a spiral anode that can be compressed under axial external force and released and extended after the axial external force is released. One end of the spare anode is provided with a snap-fit ​​through hole that cooperates with the limiting locking pin (15).

7. The coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to claim 6, characterized in that, When the telescopic controller (13) extends axially, it pushes the anode storage chamber (11) to the position of the limiting lock pin (15), so that the snap-fit ​​hole of the spare anode engages with the limiting lock pin (15), and pushes the anode to be replaced downward to the limiting lock pin (15) and disengages from the locking of the limiting lock pin (15); when the telescopic controller (13) retracts, the anode storage chamber (11) causes the spare anode to deform and disengage from the fixed groove, and the spare anode is released and extended along the fixed axis (14) under the action of elastic deformation force.

8. The coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to claim 1, characterized in that, The current collector (12) is used to disconnect the conductive connection with the anode to be replaced when the axial fixation of the anode to be replaced is released, and to switch to the standby insulation state after the conductive connection is disconnected; the elastic conductive end is used to elastically abut against the conductive connector of the standby anode after the standby anode is limited and fixed by the limiting locking pin (15), so as to restore the conductive connection between the standby anode and the current collector (12).

9. The coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to claim 8, characterized in that, The intelligent control system (4) is also used to start a small current test after the backup anode reaches the preset position, and to confirm the current distribution state of the backup anode based on the detection result of the potential difference of each spiral segment of the backup anode; when the current distribution state meets the preset conditions, it controls the elastic conductive end of the current collector (12) to conduct with the conductive connector of the backup anode.

10. A method for replacing a coaxial spiral anode for low-temperature multi-effect seawater desalination protection, characterized in that, The method using the coaxial spiral anode replacement device for low-temperature multi-effect seawater desalination protection according to any one of claims 1-9 includes the following steps: The monitoring system (3) detects the potential and consumption status of the anode (9), and the intelligent control system (4) determines whether the anode (9) meets the replacement conditions. When the anode (9) meets the replacement conditions, the front gate of the replacement chamber where the anode to be replaced is located is closed to isolate the flow channel, and the rear gate is kept open to form the intervalve cavity. Drain the residual seawater in the replacement chamber where the anode to be replaced is located and perform pressure equalization; Release the axial fixation of the anode to be replaced, disconnect the conductive connection between the anode to be replaced and the current collector (12), and switch the current collector (12) to the standby insulation state; The telescopic controller (13) is axially extended to push the anode storage chamber (11) to move axially along the fixed shaft (14), so that the snap-fit ​​hole of the spare anode engages with the limit lock pin (15), and the anode to be replaced is compressed below the limit lock pin (15). Control the telescopic controller (13) to retract, so that the anode storage chamber (11) is brought back to its original position, and the spare anode is released and extended along the fixed axis (14) after being removed from the fixed groove of the anode storage chamber (11) to the working position coaxially nested with the inner spiral cathode (10); After the backup anode reaches the preset position, the backup anode is axially fixed by the limiting locking pin (15), and the intelligent control system (4) starts a small current test to detect the potential difference of each spiral segment of the backup anode. When the potential difference of each spiral segment of the backup anode meets the preset conditions, the elastic conductive end of the current collector (12) is connected to the conductive connector of the backup anode to restore the electrochemical reaction circuit. The anode to be replaced, which is compressed below the limiting locking pin (15), continues to be in contact with seawater and participate in the reaction as an auxiliary anode. After the auxiliary anode is corroded and broken, it is intercepted and discharged through the filter element of the filter chamber (16).

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