Electrochemical water treatment device and method

Abstract

The application discloses an electrochemical water treatment device, relates to the technical field of industrial circulating cooling water treatment, and comprises an open electrolytic tank body, a plate-shaped electrode stack, an insulating flow guide shielding wall, an internal circulation driving assembly and a scale treatment assembly. The flow guide shielding wall is vertically arranged between the electrode stack and the side wall of the electrolytic tank body to form a reflux gap channel, and a guide structure is arranged on the flow guide shielding wall to provide guidance and limiting for the periodic vertical displacement of the cathode. The internal circulation driving assembly is arranged below the electrode stack and is used for driving fluid to establish a circulation flow from the electrode stack to the reflux gap channel and then back to the lower part of the electrode stack. The scale treatment assembly is arranged at the bottom of the electrolytic tank body and is used for capturing the settled scale and actively discharging the scale. The device solves the corrosion and guidance problems through the insulating flow guide shielding wall, strengthens mass transfer and scale management through internal circulation, prevents blockage through active sludge discharge, and builds an open system supporting stable operation of high-frequency regeneration of the cathode, so that stable and sustainable operation of the high-frequency regeneration of the cathode is realized.

Description

Technical Field

[0001] This application relates to the field of industrial circulating cooling water treatment technology, and in particular to an electrochemical water treatment device and method. Background Technology

[0002] Circulating cooling water constitutes the largest single application of industrial water. Electrochemical treatment technology, as a green and efficient physicochemical method, is a crucial technological route for the preparation of circulating cooling water. The core principle of electrochemical treatment technology for circulating cooling water is based on a series of physicochemical reactions generated in situ within the device during electrolysis, thereby achieving multiple functions such as water softening, sterilization and algae removal, and corrosion inhibition. The core reactions occur on the cathode and anode surfaces of the device. Among these, the online formation and removal of scale on the cathode surface is key to achieving continuous hardness removal and alkalinity reduction in circulating cooling water.

[0003] Currently, electrochemical water treatment equipment both domestically and internationally has made some progress in cathode regeneration. For example, Chinese patent application CN121020741A discloses an electrochemical water treatment device using a floating scraper, which improves the adhesion and effectiveness of single-pass scraping through the relative movement of the scraper and the cathode and the elastic compensation design.

[0004] The applicant not only focuses on technological research and development in this field but also actively promotes the standardization of the industry. The applicant is one of the lead drafting units of T / CECS 646-2019 "Technical Specification for Electrochemical Treatment of Circulating Cooling Water in Evaporative Condensers of Refrigeration Systems" and also one of the main drafting units of T / CIESC 72-2024 "Technical Specification for Bypass Electrochemical Treatment of Circulating Cooling Water". These two standards are among the first systematic technical standards in the field of electrochemical treatment equipment for circulating cooling water in China and internationally.

[0005] However, existing scraper structure improvements primarily target the scraping action itself. When facing large-scale, open-loop bypass treatment scenarios in industries like chemical and power generation, where high processing capacity and continuity are crucial, high-frequency mechanical regeneration of the cathode is necessary to achieve efficient and stable operation under high current density and prevent scale calcification. In this case, the metal components driving the scraper or cathode movement undergo severe electrochemical corrosion under strong stray electric fields, leading to mechanical jamming. Simultaneously, the large amount of scale generated by high-frequency scraping accumulates and suspends within the tank, easily clogging the sludge discharge channel. Therefore, existing electrochemical water treatment devices cannot provide a stable and continuous operating environment for this high-frequency cathode regeneration mode.

[0006] Therefore, how to ensure the stable and sustainable operation of high-frequency cathode regeneration has become a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] This application proposes an electrochemical water treatment device that enables stable and sustainable high-frequency regeneration of the cathode.

[0008] To achieve the above objectives, this application discloses the following technical solutions:

[0009] In a first aspect, this application provides an electrochemical water treatment device, comprising: an electrolytic cell body, the electrolytic cell body having an open structure; an electrode stack disposed within the electrolytic cell body, including at least one anode and at least one cathode, both the anode and cathode being plate-shaped structures and vertically spaced apart; a flow-guiding shielding wall made of insulating material, vertically positioned between the electrode stack and the side wall of the electrolytic cell body, the flow-guiding shielding wall and the side wall of the electrolytic cell body forming a vertical reflux gap channel; a guiding structure provided on the side of the flow-guiding shielding wall facing the electrode stack, used to guide and limit the periodic vertical displacement of the cathode; an internal circulation drive component disposed below the electrode stack, configured to drive fluid circulation, causing the fluid to flow through the electrode stack, through the reflux gap channel and back below the electrode stack; and a scale treatment component disposed at the bottom of the electrolytic cell body and downstream of the reflux gap channel, used to capture scale deposited from the reflux gap channel and actively discharge it.

[0010] In some embodiments, the internal circulation drive assembly includes multiple flow multipliers and an inlet main pipe, with the multiple flow multipliers evenly arranged in an array below the electrode stack;

[0011] The flow multiplier includes a primary inlet and a secondary suction inlet. The primary inlet is connected to the main water supply pipe, and the secondary suction inlet is connected to the lower part of the reflux gap channel.

[0012] In some embodiments, when the inlet pressure of the primary inlet is a preset inlet pressure, the flow multiplier is configured to make the total flow rate entering the electrode stack reach 4 to 6 times the inlet flow rate entering the primary inlet.

[0013] In some embodiments, the preset inlet pressure is 1.0 to 3.0 bar.

[0014] In some embodiments, the guide structure includes at least two, located on opposite sides adjacent to the thickness side of the cathode, to restrict horizontal movement of the cathode.

[0015] In some embodiments, a preset gap is formed between the guide structure and the cathode, the width of which is 1 mm to 4 mm.

[0016] In some embodiments, the width of the reflux gap channel is configured such that the downstream water flow velocity within the reflux gap channel is between 0.01 and 0.05 m / s.

[0017] In some embodiments, the insulating material of the current-guiding shield is selected from one or more of polypropylene, polyethylene, polyvinyl chloride, fiberglass, and polyvinylidene fluoride.

[0018] In some embodiments, the scale treatment assembly includes at least one scale collection chamber, a sludge discharge pipeline, and a mechanical conveying unit;

[0019] The scale collection chamber includes a disturbance-proof grille and an inclined bucket. The disturbance-proof grille is located at the top inlet of the scale collection chamber and below the secondary suction inlet.

[0020] The inclined bucket is located below the anti-disruption grid, and at least one sewage pipe is installed at its bottom. The two ends of the sewage pipe are connected to the inclined bucket and the sludge discharge pipe, respectively.

[0021] The mechanical conveying unit is installed inside the sludge discharge pipeline, which includes a drain outlet. The mechanical conveying unit is configured to discharge scale from the drain outlet.

[0022] In some embodiments, the mechanical conveying unit includes a first drive motor and helical blades;

[0023] The first drive motor is fixed at one end of the sludge discharge pipe, the spiral blades are arranged coaxially with the sludge discharge pipe, and the output end of the first drive motor is connected to the spiral blades for transmission.

[0024] In some embodiments, a permeate collection tank is also included, which is located outside the flow guide shield wall and is higher than the top of the flow guide shield wall but lower than the top of the electrolytic cell, for collecting permeate overflowing from the top of the flow guide shield wall;

[0025] The product water is discharged from the end of the product water collection tank through the outlet.

[0026] In some embodiments, the ratio of the total working area of ​​the cathode to the total working area of ​​the anode is 2 to 1.

[0027] In some embodiments, the electrode stack is configured to operate at a cathode operating current density of 25 to 37.5 A / m² and an anode operating current density of 50 to 75 A / m².

[0028] In some embodiments, at least two scraper mechanisms are also included, which are clamped on both sides of the cathode and have periodic relative displacement motion with respect to the cathode.

[0029] In some embodiments, the scraper mechanism includes a scraper holder, a scraper strip, and an elastic element;

[0030] The scraper holder is fixed above the electrolytic cell body. One end of the scraper bar abuts against the cathode, and the other end of the scraper bar is connected to the scraper holder through an elastic element to keep the scraper bar in continuous contact with the cathode.

[0031] Both the scraper holder and the scraper strip are made of insulating material.

[0032] In some embodiments, the cathode is driven by a drive mechanism to make periodic vertical displacements relative to the scraper mechanism.

[0033] In some embodiments, the drive mechanism includes a second drive motor and a lead screw, the lead screw being arranged in a vertical direction and drivingly connected to the second drive motor;

[0034] Four sets of drive mechanisms are arranged at the four corners of the electrolytic cell to drive the cathode as a whole and to limit it in both directions by at least two limiting members.

[0035] The total displacement of the cathode is determined by the height of the cathode in the vertical direction.

[0036] In some embodiments, the drive mechanism further includes a connecting bracket, through which multiple cathodes are fixedly connected. The connecting bracket is connected to a lead screw drive, and the cathodes are connected to a power source via flexible cables fixed on the connecting bracket.

[0037] In some embodiments, the relative displacement period between the scraper mechanism and the cathode is set to 1 to 4 hours.

[0038] As can be seen from the above technical solution, in electrochemical water treatment, the open electrolytic cell constitutes the treatment container. Water to be treated is injected into the electrolytic cell, causing a reaction on the surface of the plate-shaped electrode stack. Scale precipitates on the cathode surface, and bactericidal substances are generated on the anode surface. A flow-guiding shielding wall, positioned between the electrode stack and the sidewalls of the electrolytic cell, forms an electrical shield and also creates a reflux channel for unreacted water to flow back into the electrode stack. An internal circulation drive component establishes and maintains the circulation of the water to be treated. The scale treatment component collects the scale in the water to be treated and actively discharges it. In this process, on the one hand, the flow-guiding shielding wall provides electrical shielding, reducing corrosion of the electrolytic cell and other metal components, thereby reducing the likelihood of blockages in the high-frequency regeneration process of the cathode. On the other hand, the scale treatment component promptly collects and actively discharges the scale in the circulation, reducing clogging of the sludge discharge channel. Based on these two aspects, stable operation of the cathode regeneration process and periodic, automated cleaning of scale on the cathode surface can be achieved, thus realizing the stable and sustainable operation of the electrochemical water treatment device under high-frequency cathode regeneration conditions.

[0039] Secondly, this application provides an electrochemical water treatment method applicable to the electrochemical water treatment apparatus in any of the above embodiments. The electrochemical water treatment method includes the following steps:

[0040] S1: Inject the water to be treated into the electrolytic cell, start the internal circulation drive component, and establish circulation flow in the electrolytic cell; at the same time, energize the electrode stack to precipitate scale on the cathode surface.

[0041] S2: When the electrochemical water treatment device reaches the predetermined operating conditions, drive the cathode to move relative to the scraper mechanism to scrape off the scale on the cathode surface;

[0042] S3: The scraped scale is carried into the reflux gap channel, where it is separated by sedimentation and captured by the scale treatment component, and discharged by actively overcoming the resistance of scale caking.

[0043] In some embodiments, during the circulating flow established in step S1, the water to be treated, containing unsettled fine scale particles, is drawn in from the secondary suction port by the flow multiplier and mixed with the inlet water from the primary inlet before re-entering the electrode stack as heterogeneous nucleation sites for scale precipitation.

[0044] In some embodiments, before driving the cathode movement in step S2, the method further includes step S21: cutting off the power supply to the electrode stack; and restoring the power supply to the electrode stack after the scraping action is completed.

[0045] In some embodiments, in step S2, the predetermined condition is a time condition, where the start-up period of the relative displacement motion of the cathode with respect to the scraper mechanism is shorter than the characteristic time for the scale on the cathode surface to transform from amorphous or spheroidal to a stable calcite state.

[0046] In some embodiments, in step S1, the electrode stack operates at an anode working current density of 50~75 A / m², and the single-pass sterilization and inactivation rate is not less than 50%; the water to be treated is circulated through the electrode stack at least 4 times to achieve a cumulative inactivation rate of not less than 90%.

[0047] In some embodiments, in step S3, the active way to overcome the resistance of scale formation includes activating a mechanical conveying unit to spirally convey the scale.

[0048] The electrochemical water treatment method provided in this application, since it uses the aforementioned electrochemical water treatment device, possesses all the technical effects of the aforementioned electrochemical water treatment device, which will not be elaborated upon here. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort, and this application can be applied to other similar scenarios based on the provided drawings, all of which fall within the scope of protection of this application. Unless obvious from the linguistic context or otherwise specified, the same reference numerals in the drawings represent the same structure or operation.

[0050] Figure 1 A left view of an electrochemical water treatment device provided in an embodiment of this application;

[0051] Figure 2 A front view of an electrochemical water treatment device provided in an embodiment of this application;

[0052] Figure 3 A front view of the scale treatment component provided in an embodiment of this application;

[0053] Figure 4 A cross-sectional view of the scraper mechanism provided in an embodiment of this application;

[0054] Figure 5 A top view of the inner loop drive component provided in an embodiment of this application;

[0055] Figure 6 A detailed front view of the drive mechanism provided in an embodiment of this application;

[0056] Figure 7 A top view of the drive mechanism provided in an embodiment of this application;

[0057] The annotations in the attached figures are explained as follows:

[0058] 1. Electrochemical water treatment device;

[0059] 10. Electrolytic cell body;

[0060] 20 Electrode stack; 21 Anode; 22 Cathode;

[0061] 30. Flow guiding shield; 31. Return flow gap channel; 32. Guide structure;

[0062] 40 Internal circulation drive assembly; 41 Flow multiplier; 411 Primary inlet; 412 Secondary suction inlet; 42 Main water inlet pipe;

[0063] 50 Scale treatment component; 51 Scale collection bin; 511 Anti-disruption grille; 512 Inclined bucket; 513 Sewage pipe; 52 Sludge discharge pipe; 521 Sewage outlet; 53 Mechanical conveying unit; 531 First drive motor; 532 Spiral blade;

[0064] 60. Water collection tank; 61. Water outlet;

[0065] 70 Scraper mechanism; 71 Scraper holder; 72 Scraper strip; 73 Elastic element;

[0066] 80 Drive mechanism; 81 Second drive motor; 82 Lead screw; 83 Limiting component; 84 Connecting bracket; 85 Flexible cable. Detailed Implementation

[0067] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the application and not intended to limit it. The described embodiments are only a part of the embodiments of the present application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without inventive effort are within the scope of protection of the present application.

[0068] The first aspect of this application discloses an electrochemical water treatment device 1, which enables the cathode 22 to be regenerated at high frequency and operate stably and sustainably.

[0069] See Figures 1 to 3 To achieve the above objectives, this application discloses the following technical solutions:

[0070] An electrochemical water treatment device 1 includes: an electrolytic cell 10, which is an open structure; an electrode stack 20 disposed within the electrolytic cell 10, including at least one anode 21 and at least one cathode 22, both the anode 21 and the cathode 22 being plate-shaped structures and arranged vertically at intervals; and a flow-guiding shielding wall 30, made of insulating material, vertically positioned between the electrode stack 20 and the side wall of the electrolytic cell 10, forming a vertical reflux gap channel 31 with the side wall of the electrolytic cell 10; the flow-guiding shielding wall 30... A guide structure 32 is provided on the side facing the electrode stack 20 to provide guidance and limit for the periodic vertical displacement of the cathode 22; the internal circulation drive component 40 is located below the electrode stack 20 and is configured to drive the fluid circulation flow, so that the fluid flows through the electrode stack 20, passes through the return gap channel 31 and returns to the bottom of the electrode stack 20; the scale treatment component 50 is located at the bottom of the electrolytic cell 10 and downstream of the return gap channel 31 to capture the scale that settles from the return gap channel 31 and actively discharge it.

[0071] As can be seen from the above technical solution, during electrochemical water treatment, the open electrolytic cell 10 constitutes the treatment container. Water to be treated is injected into the electrolytic cell 10, causing a reaction on the surface of the plate-shaped electrode stack 20. Scale is deposited on the surface of the cathode 22, and bactericidal substances are generated on the surface of the anode 21. The flow-guiding shielding wall 30, located between the electrode stack 20 and the sidewall of the electrolytic cell 10, forms an electrical shield and also creates a reflux gap channel 31, allowing unreacted water to flow back into the area below the electrode stack 20. The internal circulation drive component 40 establishes and maintains the circulation of the water to be treated. The scale treatment component 50 collects the scale in the water to be treated and actively discharges it. In this process, on the one hand, the flow-guiding shielding wall 30 provides electrical shielding, reducing corrosion of the electrolytic cell 10 and other metal components, thereby reducing the stagnation in the high-frequency regeneration process of the cathode 22; on the other hand, the scale treatment component 50 promptly collects the scale in the circulation and actively discharges it, reducing blockage of the sludge discharge channel. Based on the above two aspects, the stable operation of the cathode 22 regeneration process and the periodic and automated cleaning of scale on the cathode 22 surface can be achieved, thereby realizing the stable and sustainable operation of the electrochemical water treatment device 1 under the high-frequency regeneration condition of the cathode 22.

[0072] Specifically, the aforementioned internal circulation drive component 40 is not a single power source, but rather consists of one or more inlet main pipes 42 and multiple independently operating flow multipliers 41 working in concert. See also Figure 3 and Figure 5 These flow multipliers 41 are preferably Venturi nozzles. They are not placed randomly, but are evenly arranged in a regular array in the lower region of the entire electrode stack 20 to ensure that the upward flowing water can evenly cover the surface of each electrode and avoid flow dead zones.

[0073] Each Venturi nozzle has two key fluid interfaces: a primary inlet 411 and a secondary suction inlet 412. The primary inlet 411 is connected to the main water inlet 42 to introduce pressurized water from an external pump; while the secondary suction inlet 412 is connected to the bottom space of the upper return gap channel 31. Its working principle is based on Bernoulli's principle: when pressurized primary water flows through the constriction section of the Venturi nozzle at a high velocity, the velocity reaches its maximum at the point where the cross-sectional area of ​​the throat is the smallest. According to the principles of fluid mechanics, the static pressure at this point will drop to its lowest level, or even form a local negative pressure zone.

[0074] This negative pressure zone connects directly to the secondary suction port 412, generating a powerful suction force that continuously draws in the settled return liquid from the bottom of the return gap channel 31. The primary feed water mixes with the drawn-in return liquid in the expansion section of the nozzle, reducing its velocity and converting some of its kinetic energy into pressure energy. Ultimately, the resulting total fluid flow, significantly higher than the primary feed water flow rate and velocity, is ejected from the Venturi nozzle outlet and directed towards the electrode stack 20 area above. By incorporating the internal circulation drive component 40, a high-velocity internal circulation environment is created using the pressure energy of the primary water, without relying on an external high-flow-rate circulation pump. This enhances mass transfer and reduces system energy consumption.

[0075] The performance parameters of the flow multiplier 41 directly determine the intensity and treatment effect of the internal circulation. Under nominal operating conditions, that is, when the inlet water pressure delivered to the primary inlet 411 through the inlet main pipe 42 is between 1.0 and 3.0 bar, each Venturi nozzle can generate a strong ejection effect, preferably stabilizing the inlet water pressure of the primary inlet 411 at 1.5 bar.

[0076] Specifically, the flow rate of the reflux liquid drawn in through the secondary inlet 412 can reach approximately four times the flow rate of the water entering through the primary inlet 411, thereby increasing the total fluid flow rate from the Venturi nozzle outlet, which then merges and enters the upper electrode stack 20, to five times the flow rate of the water entering through the primary inlet 411. This flow rate doubling is a core performance indicator, meaning that only one unit of fresh water can drive five units of fluid to repeatedly flush the surface of the electrode stack 20 at high flow rates. This process generates high turbulence, for example, the Reynolds number Re can reach over 14,000, which enhances reactant mass transfer and eliminates concentration polarization; at the same time, it can also effectively flush away bubbles attached to the electrode surface, reduce bubble coverage, and indirectly increase the operating current density of the cathode 22 and anode 21.

[0077] See Figure 1 and Figure 5 While providing flow channel separation, the flow-guiding shielding wall 30 also integrates a guiding structure 32 on its inner side, which is the core for ensuring the high-frequency, long-period, and reliable movement of the cathode 22. Specifically, the flow-guiding shielding wall 30 is arranged around at least two sides of the electrode stack 20. On the plate surface of the flow-guiding shielding wall 30 facing the electrode stack 20, corresponding to the position of each cathode 22, at least two vertically extending limiting strips are integrally formed or welded. These two limiting strips are precisely aligned with and adjacent to the left and right sides of the cathode 22 plate in the thickness direction.

[0078] During static installation, the two sides of the cathode 22 plate are not tightly fitted or interference-fitted with the corresponding limiting strips; instead, a pre-set gap of 1 to 4 millimeters is intentionally maintained. This ingenious gap design is key to achieving flexible limiting: during the normal vertical lifting and lowering of the cathode 22 plate, this gap prevents contact and friction with the limiting strips, resulting in minimal movement resistance, low energy consumption, and no wear. Only when the cathode 22 plate is about to experience lateral swaying or rotation beyond its range due to water flow impact will its sides contact the limiting strips, thus being forcibly constrained back to the correct track, preventing collisions and short circuits with adjacent anodes 21. This design ensures guiding accuracy while minimizing wear and jamming risks of moving parts.

[0079] The reflux gap channel 31 is not only a flow passage, but also a well-designed gravity settling separation zone. Its width is the annular distance between the guide flow shield wall 30 and the side wall of the electrolytic cell 10, and it is determined by fluid dynamics calculations. The goal is to keep the average downward flow velocity of the fluid in the reflux gap channel 31 stable in a low range of 0.01 to 0.05 m / s when the electrochemical treatment device is operating under nominal conditions.

[0080] For example, in a preferred embodiment, by designing the channel width to be approximately 150 mm, the downward flow velocity can be controlled at around 0.03 m / s. At this low flow velocity, the downward drag force exerted by the water flow on solid particles is very weak. For larger, heavier scale particles, such as those larger than 30-50 micrometers, entering the return gap channel 31 from the circulating water flow, their own gravity is sufficient to overcome the drag force of the water flow, allowing them to gradually settle and eventually fall into the collection area at the bottom of the return gap channel 31. Conversely, small, lightweight particles cannot settle and continue to be carried by the water flow and participate in the circulation. This design achieves automatic classification of scale particles, ensuring that only particles large enough to be captured by the subsequent scale treatment component 50 are separated, while fine particles that can serve as beneficial nucleation seeds remain in the system for continued circulation.

[0081] The reason why the current-guiding shielding wall 30 can fulfill the critical task of electrical shielding is fundamentally due to the choice of its materials. It must be made of insulating materials, and the engineering plastics that can be selected include one or more of polypropylene, polyethylene, polyvinyl chloride, fiberglass, and polyvinylidene fluoride.

[0082] For example, using polypropylene sheets formed by hot-melt welding is an economical and reliable choice. Polypropylene not only has excellent insulation properties but also good corrosion resistance, resisting chloride ions in circulating water, and it also has a certain mechanical strength. When erected between the electrode stack 20 and the metal tank, it effectively inserts an insulating barrier between the two, thereby greatly reducing the path of stray current overflowing from the edge of the electrode stack 20 to the metal electrolytic tank 10, thus preventing the sidewall of the electrolytic tank 10 from becoming a stray anode 21 for the electrolytic reaction and effectively reducing the risk of corrosion failure.

[0083] The following section will describe the scale treatment component 50 in detail. (See also...) Figure 3 The main body of the scale treatment component 50 is a scale collection chamber 51 located directly below the settling zone. Its top inlet is equipped with an anti-disturbance grille 511 with a suitable aperture, which acts like a sieve. It can intercept large pieces of debris that may fall and prevent particles that have settled in the chamber from being resuspended by accidental rising water flow or air bubbles, ensuring a collection effect of only entering and not exiting.

[0084] Below the anti-disruption grille 511 is a sloping bucket 512 with an inverted pyramidal or frustum-shaped cross section. The angle between its inclined wall and the horizontal plane is usually greater than 60°, and gravity naturally guides the sediment to the collection point at the bottom center or both sides. At least one sewage pipe 513 is provided at the bottom of the sloping bucket 512, which is rigidly connected to a horizontal sludge discharge pipe 52 through a flange.

[0085] The mechanical conveying unit 53 installed inside the sludge discharge pipe 52 has a core component: a spiral blade 532 driven to rotate by a first drive motor 531. When scale accumulates to a certain amount in the inclined hopper 512, or when the system discharges sludge according to a set time, the first drive motor 531 is activated. The rotating spiral blade 532 produces two key functions: first, its spiral surface generates a strong radial shear force on the scale, especially scale that may have partially hardened due to stagnation, breaking up the clumps; second, its rotational motion generates a continuous axial thrust, forcibly conveying the scale forward like a screw conveyor until it is pushed out from the drain port 521 at the end of the pipe. This method actively applies mechanical energy, directly overcoming the hardening force between scale particles and the static friction with the pipe wall, thus improving the scale discharge efficiency.

[0086] See Figure 1 and Figure 5To achieve separation of the permeate from the internal circulating liquid and scale, the device is equipped with an independent permeate collection and output system. In a preferred embodiment, an annular permeate collection tank 60 surrounding the flow-guiding shield wall 30 is located outside the flow-guiding shield wall 30, and the top height of the permeate collection tank 60, i.e., the overflow weir top, is designed to be lower than the top of the electrolytic cell 10 but higher than the top of the flow-guiding shield wall 30. This height difference forms a natural overflow weir. The water flow that has been treated by the electrode stack 20 and rises, when it reaches the top of the flow-guiding shield wall 30, its uppermost layer of clear water with low turbidity and low hardness will overflow over the top of the flow-guiding shield wall 30 and the top of the permeate collection tank 60 and fall into the permeate collection tank 60. The lower layer of liquid containing scale particles is blocked by the side wall of the permeate collection tank 60 and can only flow down through the return gap channel 31. The clean water entering the product water collection tank 60 is finally discharged through the outlet 61 set on its side wall or bottom and the external pipe, and enters the external circulating water system. This separation method based on gravity difference and overflow principle is simple in structure, requires no power, and has good separation effect. It is the key to ensuring the quality of product water and the balance of system water circulation.

[0087] The structural parameters of the electrode stack 20 are central to optimizing its electrochemical performance. In a validated preferred embodiment, the ratio of the total effective working area of ​​all cathodes 22 to the total effective working area of ​​all anodes 21 in the electrode stack 20 is 2:1. This means that at the same current, the current density of the cathodes 22 is half that of the anodes 21. This design fully utilizes the different functions of the cathodes and anodes 21: the large-area cathodes 22 provide ample deposition area to accommodate the large amounts of scale generated at high frequencies, improving hardness removal capabilities; while the small-area anodes 21 withstand higher current densities at the same total current.

[0088] Combined with the high mass transfer conditions created by the aforementioned internal circulation drive component 40, the electrochemical water treatment device 1 provided in this application can be configured to operate stably at current densities significantly higher than conventional levels. Specifically, the working current density of the cathode 22 can reach 25~37.5 A / m², while the corresponding working current density of the anode 21 reaches 50~75 A / m². The high anode 21 current density can generate higher concentrations of active chlorine, ozone, and other strong oxidizing substances in situ, greatly improving the instantaneous sterilization and oxidation capabilities; the high cathode 22 current density increases the hardness removal rate per unit area. The combination of these two factors significantly improves the treatment efficiency per unit volume or per unit area of ​​the electrochemical water treatment device 1.

[0089] To achieve efficient surface cleaning, this electrochemical water treatment device 1 employs a double-sided clamping scraper mechanism 70. (See also...) Figure 4Specifically, for each cathode 22 in the electrode stack 20, a set of scraper mechanisms 70 is independently provided on both its front and back surfaces. These two sets of scraper mechanisms 70 clamp the cathode 22 plate and have periodic relative displacement movement with its surface. For example, the scraper mechanism 70 is fixed and only the cathode 22 moves, or the cathode 22 is fixed and the scraper mechanism 70 moves. This configuration means that in one scraping action, both working surfaces of the cathode 22 plate can be cleaned simultaneously, doubling the efficiency and ensuring balanced force, preventing uneven force on both sides of the cathode 22 from causing bending or tilting of the cathode 22.

[0090] Each scraper mechanism 70 mainly consists of three components: a scraper holder 71, a scraper strip 72, and an elastic element 73. In a preferred embodiment, the scraper holder 71 is a structural component that is securely fixed to a crossbeam or support frame above the electrolytic cell 10, remaining absolutely stationary throughout the scraping process. One end of the scraper strip 72 abuts against the cathode 22, and the other end of the scraper strip 72 is connected to the scraper holder 71 via the elastic element 73, which can be a set of pre-compressed stainless steel springs.

[0091] The elastic element 73 provides a continuous and adjustable clamping force, ensuring that the blade of the scraper 72 remains firmly and evenly pressed against the surface of the cathode 22 plate even when it wears or experiences minor deformation, maintaining a constant scraping force and thus ensuring the uniformity of the scraping effect each time. Crucially, both the scraper holder 71 and the scraper 72 are made of insulating materials. For example, the scraper holder 71 can be made of polyoxymethylene or reinforced nylon, and the scraper 72 can be made of polyethylene or polytetrafluoroethylene. This choice of insulating material, following the current-conducting shielding wall 30, is the second line of defense against stray current corrosion at the actuator level, ensuring the long lifespan of the scraper mechanism 70 itself in strong electric field environments.

[0092] To achieve the scraping mode where the scraper mechanism 70 is fixed and the cathode 22 moves, the drive mechanism 80 is specifically a four-corner screw 82 synchronous lifting mechanism. At each of the four corners of the top of the electrolytic cell 10, a precision ball screw 82 or trapezoidal screw 82 is vertically installed. The top of each screw 82 is driven by an independent second drive motor 81 via a coupling. These four second drive motors 81 are strictly synchronized by the control system to ensure they operate at the same speed and direction. The tops of all the cathode 22 plates are connected into a single frame by a rigid top bracket. When the four second drive motors 81 receive a command to rotate synchronously, they drive the four screws 82 to rotate synchronously, thereby causing all the cathode 22 plates to perform high-precision, vertically synchronized lifting and lowering movements.

[0093] To ensure safe control of the movement range, at least two limit switches 83 are provided at both ends of the stroke of the drive mechanism 80. Typically, upper and lower limit switches are installed on the lead screw 82 or the connecting bracket 84. When the connecting bracket 84 rises to a preset highest position, such as the peak of the corresponding scraping stroke, or descends to a preset original working position, the corresponding limit switch is triggered. The signal is immediately transmitted to the control system, commanding all second drive motors 81 to stop operating, thereby achieving reliable bidirectional stroke limiting and protection.

[0094] The total displacement stroke of the cathode 22 is a key design parameter, determined by its vertical height and typically slightly less. For example, for a cathode 22 plate with a height of 1.5 meters, the scraping stroke can be set to 1.49 meters. This design ensures that during a complete lifting process, the entire working surface of the cathode 22 essentially sweeps across the coverage area of ​​the fixed scraper bar 72, and also prevents the cathode 22 from detaching from the scraper mechanism 70, ensuring stable contact between the scraper bar 72 and the cathode 22.

[0095] Because the cathode 22 plate requires a strong direct current during operation and needs to move up and down during scraping, its electrical connection must be able to withstand both high current and reciprocate. Therefore, a large-section flexible cable 85 is used to power the cathode 22. One end of this flexible cable 85 is connected to the conductive part of the connecting bracket 84 and is conductive to all cathode 22 plates; the other end is connected to a rigid busbar from the DC power supply. This flexible connection method allows the connecting bracket 84 to undergo significant vertical displacement while maintaining reliable, low-resistance, and unobstructed electrical connections.

[0096] Figure 1 and Figure 2 An embodiment is shown where the connecting bracket 84 is located on top of the second drive motor 81 and is lifted or reset via a lead screw 82. Figure 6 and Figure 7 An embodiment is shown in which the connecting bracket 84 is located at the bottom of the second drive motor 81 and is lifted or reset by the lead screw 82. Both embodiments ensure that the cathode 22 stably and accurately sweeps across the scraper blade 72 during the scraping stroke, and the electrical connections and mechanical limiting structures are compatible with the above embodiments, and both fall within the protection scope of this invention.

[0097] The relative displacement between the entire scraper mechanism 70 and the cathode 22 is automatically triggered by the control system according to a preset cycle. This cycle is set to 1 to 4 hours, for example, 2 hours under standard operating conditions. This cycle setting has a rigorous scientific basis, and its core purpose is to actively block the crystal transformation of scale. Newly formed scale is initially mostly soft aragonite or amorphous, but after several hours it gradually transforms into hard, dense, and highly adhesive calcite. Setting the mechanical scraping cycle to 1 to 4 hours is precisely to ensure that most of the scale is removed in the form of soft scale before it has completed its transformation into calcite. For example, the characteristic time of calcite transformation is usually greater than 4 hours, which makes each scraping resistance low, energy consumption low, and fundamentally prevents the risk of equipment jamming caused by hard scale formation. This is a key process parameter for maintaining the long-term feasibility of the high-frequency regeneration mode.

[0098] The second aspect of this application describes an electrochemical water treatment method applicable to the electrochemical water treatment device 1 in any of the above embodiments. The method operates automatically in a cyclical manner and includes the following three core steps:

[0099] S1: A set flow rate and pressure of circulating cooling water to be treated are introduced into the device. Simultaneously, the internal circulation drive component 40 (such as a Venturi array) is activated, rapidly establishing a powerful closed-loop flow within the device. This flow originates from below the electrode stack 20, flows upwards across the entire active surface of the electrode stack 20, then partially overflows, while the remaining portion flows downwards at a reduced speed through the return gap channel 31, and finally is re-absorbed and returns to the bottom of the electrode stack 20. Simultaneously, a calculated and set DC voltage and current are applied to the electrode stack 20, bringing it into a highly efficient operating state. On the cathode 22 surface, due to a localized increase in pH, calcium carbonate scale continuously precipitates; on the anode 21 surface, electrolysis produces strong oxidizing substances such as hypochlorous acid and ozone, used for sterilization and algae removal.

[0100] S2: When the electrochemical water treatment device 1 has been running continuously for a preset period of time, such as exactly 2 hours since the last scale removal, the control system automatically triggers the regeneration program. In this program, the driven cathode 22, as a whole, performs a complete vertical displacement cycle relative to the fixed scraper mechanism 70, for example, rising a distance equal to the height of the cathode 22 plate, and then descending to reset. Utilizing the shearing force generated by the tight fit and relative motion between the two, the still-soft scale layer attached to the surface of the cathode 22 is scraped off.

[0101] S3: This process overlaps with steps S1 and S2 in time: the scale particles peeled off by the scraper are immediately carried by the strong circulating water flow established in step S1 and then enter the return gap channel 31. Inside the channel, due to the low flow rate environment created by the design, larger and heavier particles settle and separate from the water flow under the action of gravity, and slide down the side wall of the return gap channel 31, and are finally captured by the scale treatment component 50 located at the downstream outlet of the channel; subsequently, the scale treatment component 50 does not wait for natural discharge, but uses a mechanical method that can actively overcome the resistance of the scale itself to continuously and reliably push these scale particles out of the electrochemical water treatment device 1 system and into the sludge disposal process.

[0102] These three steps—treatment, regeneration, and scale removal—recur repeatedly, forming a complete, efficient, and fully automated closed-loop industrial water treatment process.

[0103] To improve scaling efficiency, in step S1, extremely fine calcium carbonate microcrystals remaining in the water after sedimentation and separation within the reflux gap channel 31 are considered seed crystals and will reach the bottom of the channel with the downstream water flow. At this time, this water containing seed crystals is drawn in by the internal circulation drive component 40, such as the secondary suction port 412 of the Venturi nozzle, mixed with the primary feed water, and then accelerated and transported back to the electrode stack 20 area.

[0104] When the water carrying a large number of seed crystals flows through the high-pH reaction zone on the cathode 22 surface again, calcium and carbonate ions in the water preferentially undergo heterogeneous nucleation and crystal growth on the surface of these seed crystal particles. This process is much easier and faster than forming new crystal nuclei directly on the metal substrate of the cathode 22. Its direct benefit is that it encourages more scale to be separated and removed during circulation, rather than all of it densely depositing on the cathode 22 surface. This not only significantly improves the overall hardness removal efficiency of the device but also simultaneously reduces the scaling load on the cathode 22 plate, thus providing important process optimization for extending the scaling cycle and maintaining the long-term, efficient, and stable operation of the electrochemical water treatment device 1.

[0105] To improve the safety factor in the mechanical regeneration operation of cathode 22, the control system must first cut off the power supply to electrode stack 20 before activating the cathode 22 drive mechanism 80 to perform the scraping displacement movement. This ensures that the electrolytic reaction completely stops. Power supply to electrode stack 20 is only restored after the scraping action is completed and cathode 22 has returned to its initial working position. This forced sequence of power-off-scraping-reset-power-on constitutes the core safety interlock. Its purpose is to reduce the risk of electrical faults such as inter-electrode arcing and short-circuit discharge that may occur when cathode 22, under energized conditions, undergoes relative displacement with the scraper mechanism 70. This effectively protects the electrode coating, scraper mechanism 70, and power supply equipment, and is a necessary guarantee for ensuring the stability and reliability of the electrical system and preventing safety accidents during long-term automated high-frequency regeneration.

[0106] In step S2, the predetermined condition is preferably a time-based condition. For example, in some preferred embodiments, the control system periodically triggers the scale removal and regeneration program with a fixed cycle of 1 to 4 hours. This time range is not based on experience but stems from in-depth research on the crystallization transformation kinetics of scale on the cathode 22 surface. The core principle is that the set mechanical scraping cycle must be shorter than the characteristic time for the newly formed, weakly adhered metastable calcium carbonate on the cathode 22 surface to undergo a significant transformation into the hard and highly adhered stable calcite crystal form. By setting the frequency of mechanical intervention before the calciteification process is completed, it is ensured that the scale removed each time is still in a soft state. Therefore, this method reduces the risk of scale hardening and caking through proactive prevention, thereby ensuring the long-term sustainability and low-energy operation of the high-frequency regeneration mode.

[0107] To achieve efficient sterilization, during operation, the electrode stack 20 is operated at a current density of 50-75 A / m² at the anode 21. This generates a high concentration of active oxidizing substances, such as hypochlorous acid, at the anode 21 interface, ensuring that the inactivation rate of microorganisms is no less than 50% when water flows through the reaction zone of the electrode stack 20 in a single pass. Furthermore, combined with the unique high-rate internal circulation flow of this electrochemical water treatment device 1, the water to be treated flows through the reaction zone of the electrode stack 20 at least four times on average before discharge. Based on the probability model of microbial inactivation, under the condition that the single inactivation rate is no less than 50%, after at least four cycles, a cumulative inactivation rate of no less than 90% can be achieved. This process method generates powerful disinfection through high current density and achieves repeated action through multiple internal circulations, achieving a deep and stable sterilization effect without the addition of chemical agents, thus meeting the stringent microbial control standards of industrial circulating water systems.

[0108] During the discharge phase, the active method to overcome the resistance of scale buildup is to activate the mechanical conveying unit 53 to convey the scale via a spiral conveyor. When sludge needs to be discharged, the first drive motor 531 is activated, and the rotating spiral blades 532 apply radial shearing force and axial pushing force to the scale in the collection chamber. The radial shearing force is used to break up any scale that may have hardened, disrupting its internal structure; the axial pushing force continuously forces the scale material toward the drain outlet 521. This active discharge method based on mechanical shearing and pushing effectively overcomes the cohesive force between scale particles and the frictional force between them and the pipe wall, thereby ensuring that the scale can be reliably and continuously discharged from the system regardless of whether it is loose or hardened, guaranteeing the long-term smoothness and stability of the water treatment process.

[0109] In the above context, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0110] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. "And / or" in this article is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone.

[0111] It should be noted that, for ease of description, only the parts relevant to the application are shown in the accompanying drawings. Unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0112] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed, and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. The scope of this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described application concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An electrochemical water treatment device, characterized in that, include: Electrolytic cell body (10), wherein the electrolytic cell body (10) is an open structure; An electrode stack (20) is disposed within the electrolytic cell body (10) and includes at least one anode (21) and at least one cathode (22). The anode (21) and the cathode (22) are both plate-shaped structures and are arranged vertically at intervals. A current-guiding shielding wall (30), made of insulating material, is vertically placed between the electrode stack (20) and the side wall of the electrolytic cell (10), and the current-guiding shielding wall (30) and the side wall of the electrolytic cell (10) form a vertical return gap channel (31). The current-guiding shield wall (30) is provided with a guide structure (32) on the side facing the electrode stack (20) to provide guidance and limit for the periodic vertical displacement of the cathode (22); An internal circulation drive assembly (40) is disposed below the electrode stack (20) and is configured to drive fluid circulation, so that the fluid flows through the electrode stack (20), and returns to the bottom of the electrode stack (20) through the return gap channel (31); The scale treatment component (50) is located at the bottom of the electrolytic cell (10) and downstream of the reflux gap channel (31) to capture the scale that settles from the reflux gap channel (31) and actively discharge it.

2. The electrochemical water treatment device as described in claim 1, characterized in that, The internal circulation drive assembly (40) includes multiple flow multipliers (41) and a main water inlet pipe (42), with the multiple flow multipliers (41) arranged in an array uniformly below the electrode stack (20); The flow multiplier (41) includes a primary inlet (411) and a secondary suction inlet (412). The primary inlet (411) is connected to the main water inlet (42), and the secondary suction inlet (412) is connected to the lower part of the reflux gap channel (31).

3. The electrochemical water treatment device as described in claim 2, characterized in that, When the inlet pressure of the primary inlet (411) is a preset inlet pressure, the flow multiplier (41) is configured to make the total flow rate entering the electrode stack (20) reach 4 to 6 times the inlet flow rate entering the primary inlet (411).

4. The electrochemical water treatment device as described in claim 3, characterized in that, The preset inlet pressure is 1.0~3.0 bar.

5. The electrochemical water treatment device as described in claim 1, characterized in that, The guide structure (32) includes at least two and is located on both sides adjacent to the thickness side of the cathode (22) to restrict the horizontal movement of the cathode (22).

6. The electrochemical water treatment device as described in claim 5, characterized in that, A preset gap is formed between the guide structure (32) and the cathode (22), and the width of the preset gap is 1 mm to 4 mm.

7. The electrochemical water treatment device as described in claim 1, characterized in that, The width of the return gap channel (31) is configured such that the downstream water flow velocity within the return gap channel (31) is between 0.01 and 0.05 m / s.

8. The electrochemical water treatment device as described in claim 1, characterized in that, The insulating material of the current-guiding shield wall (30) is selected from one or more of polypropylene, polyethylene, polyvinyl chloride, fiberglass, and polyvinylidene fluoride.

9. The electrochemical water treatment device as described in claim 2, characterized in that, The scale treatment component (50) includes at least one scale collection chamber (51), a sludge discharge pipe (52), and a mechanical conveying unit (53). The scale collection chamber (51) includes a disturbance-proof grille (511) and an inclined bucket (512). The disturbance-proof grille (511) is located at the top inlet of the scale collection chamber (51) and below the secondary suction port (412). The inclined bucket (512) is located below the anti-disturbance grid (511), and at least one sewage pipe (513) is provided at its bottom. The two ends of the sewage pipe (513) are respectively connected to the inclined bucket (512) and the sludge discharge pipe (52). The mechanical conveying unit (53) is disposed within the sludge discharge pipe (52), which includes a drain outlet (521), and the mechanical conveying unit (53) is configured to discharge scale from the drain outlet (521).

10. The electrochemical water treatment device as described in claim 9, characterized in that, The mechanical conveying unit (53) includes a first drive motor (531) and a spiral blade (532); The first drive motor (531) is fixed at one end of the sludge discharge pipe (52), the spiral blade (532) is coaxially arranged with the sludge discharge pipe (52), and the output end of the first drive motor (531) is connected to the spiral blade (532) for transmission.

11. The electrochemical water treatment device as described in claim 1, characterized in that, It also includes a product water collection tank (60), which is located outside the flow guide shield wall (30) and is higher than the top of the flow guide shield wall (30) and lower than the top of the electrolytic cell (10), for collecting product water overflowing from the top of the flow guide shield wall (30); The end of the water collection tank (60) discharges the water through the outlet (61).

12. The electrochemical water treatment device as described in claim 1, characterized in that, The ratio of the total working area of ​​the cathode (22) to the total working area of ​​the anode (21) is 2 to 1.

13. The electrochemical water treatment device as described in claim 1, characterized in that, The electrode stack (20) is configured to operate at a cathode (22) current density of 25~37.5A / m² and an anode (21) current density of 50~75A / m².

14. The electrochemical water treatment device as described in claim 1, characterized in that, It also includes at least two sets of scraper mechanisms (70), which are clamped on both sides of the cathode (22) and have periodic relative displacement motion with respect to the cathode (22).

15. The electrochemical water treatment device as described in claim 14, characterized in that, The scraper mechanism (70) includes a scraper holder (71), a scraper strip (72), and an elastic element (73); The scraper holder (71) is fixed above the electrolytic cell body (10). One end of the scraper strip (72) abuts against the cathode (22), and the other end of the scraper strip (72) is connected to the scraper holder (71) through an elastic member (73) to keep the scraper strip (72) in continuous contact with the cathode (22). Both the scraper holder (71) and the scraper strip (72) are made of insulating material.

16. The electrochemical water treatment device as described in claim 14, characterized in that, The cathode (22) is driven by a drive mechanism (80) to make periodic vertical displacements relative to the scraper mechanism (70).

17. The electrochemical water treatment device as described in claim 16, characterized in that, The drive mechanism (80) includes a second drive motor (81) and a lead screw (82), the lead screw (82) is arranged in a vertical direction and is connected to the second drive motor (81) in a transmission connection; The four sets of drive mechanisms (80) are arranged at the four corners of the electrolytic cell body (10) to drive the cathode (22) as a whole and to limit it in both directions by at least two limiting members (83); The total displacement stroke of the cathode (22) is determined by the height of the cathode (22) in the vertical direction.

18. The electrochemical water treatment device as described in claim 17, characterized in that, The drive mechanism (80) also includes a connecting bracket (84), through which a plurality of cathodes (22) are fixedly connected. The connecting bracket (84) is connected to the lead screw (82) for transmission. The cathodes (22) are connected to the power supply through a flexible cable (85) fixed on the connecting bracket (84).

19. The electrochemical water treatment device as described in claim 14, characterized in that, The relative displacement period between the scraper mechanism (70) and the cathode (22) is set to 1 to 4 hours.

20. An electrochemical water treatment method, characterized in that, An electrochemical water treatment apparatus applicable to any one of claims 1-19, wherein the electrochemical water treatment method comprises the following steps: S1: Inject the water to be treated into the electrolytic cell (10), start the internal circulation drive component (40), and establish circulation flow in the electrolytic cell (10); at the same time, energize the electrode stack (20) and deposit scale on the cathode (22) surface; S2: When the electrochemical water treatment device reaches the predetermined operating conditions, drive the cathode (22) to move in order to scrape off the scale on the surface of the cathode (22); S3: The scraped scale is carried into the reflux gap channel (31), and after sedimentation and separation, it is captured by the scale treatment component (50) and discharged in a way that actively overcomes the resistance of scale caking.

21. The electrochemical water treatment method as described in claim 20, characterized in that, In the circulating flow established in step S1, the water to be treated, containing unsettled fine scale particles, from the reflux gap channel (31) is drawn in from the secondary suction port (412) by the flow multiplier (41), and mixed with the water inlet from the primary inlet (411) before re-entering the electrode stack (20) as heterogeneous nucleation sites for scale precipitation.

22. The electrochemical water treatment method as described in claim 20, characterized in that, Before driving the cathode (22) to move in step S2, step S21 is also included: cutting off the power supply to the electrode stack (20); and restoring the power supply to the electrode stack (20) after the scraping action is completed.

23. The electrochemical water treatment method as described in claim 20, characterized in that, In step S2, the predetermined condition is a time condition, and the start-up period of the relative displacement movement of the cathode (22) relative to the scraper mechanism (70) is shorter than the characteristic time for the scale on the surface of the cathode (22) to transform from aragonite or amorphous state to calcite stable state.

24. The electrochemical water treatment method as described in claim 20, characterized in that, In step S1, the electrode stack (20) operates at a current density of 50~75A / m² at the anode (21), and the sterilization and inactivation rate of a single pass through the tank is not less than 50%; the water to be treated is circulated through the electrode stack (20) at least 4 times to achieve a cumulative inactivation rate of not less than 90%.

25. The electrochemical water treatment method as described in claim 20, characterized in that, In step S3, the method of actively overcoming the resistance of scale formation includes starting the mechanical conveying unit (53) to convey the scale in a spiral manner.

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