Method for on-line descaling of electrolysis cell electrodes

Abstract

This invention relates to an online descaling method for electrodes in an electrolytic cell. The electrolytic cell includes a descaling unit and an electrolysis unit. The method includes the following steps: Step S1: Controlling the operation of the electrolysis unit to generate electrolytic products; Step S2: When the descaling trigger condition is met, starting the descaling unit, which generates acidic substances to descale the electrode surface; wherein, during the descaling operation, the electrolysis unit maintains production operation or is suspended. After the electrolysis unit starts operating, electrolyzing water produces electrolyzed water products. During electrolysis, hydrogen ions are reduced to hydrogen gas at the cathode of the electrolysis unit, increasing the hydroxide ion concentration and making the water near the electrode alkaline, which promotes the gradual deposition of scale (such as calcium carbonate, magnesium hydroxide, etc.) on its surface. When the descaling trigger condition is met, the descaling unit starts, generating acidic substances, making the water near the electrode acidic. The acidic environment can dissolve the scale formed on the electrode surface, achieving the purpose of surface descaling of the electrode, effectively preventing the performance degradation of the electrolytic cell, and improving the overall service life of the electrolytic cell. Compared to the traditional reverse-polarity descaling mode, the electrolysis mode of this application can separate and control the electrolysis reaction and the descaling reaction, reducing the difficulty of system control.

Description

Technical Field

[0001] This invention relates to an online descaling method for electrodes in an electrolytic cell. Background Technology

[0002] Currently, electrochemical water treatment technology is widely used in water treatment, disinfection, and chemical preparation due to its high efficiency and environmental friendliness. During the water electrolysis reaction, the area near the cathode is alkaline (2H₂O + 2e⁻ → H₂↑ + 2OH⁻). In this alkaline environment, hardness ions such as calcium and magnesium in the water easily accumulate on the electrode surface after prolonged operation, leading to increased cell voltage and energy consumption, reduced current efficiency, and affecting the electrode's lifespan. Current technologies often use a polarity reversal method, which periodically reverses the polarity of the original cathode and anode, transforming the original cathode (scale surface) into the anode. However, this method has the following limitations: (1) It is required that there is no Schottky barrier on the electrode plate when the electrode is reversed; otherwise, there will be an electron-blocking layer on the electrode surface, which will prevent normal electrolysis. At present, the anode of the electrolytic water tank is generally a semiconductor and the cathode is generally a metal sheet, which will inevitably lead to the existence of the Schottky barrier, making the reverse electrode unable to work properly. (2) The reverse electrode setting has high requirements for the descaling time and current density. When the descaling time is too long and the current density is set too high, it will aggravate the corrosion of the electrode plate. (3) Theoretically, polarity reversal is required before the scale hardens. However, the oxide coating of the commonly used anode material DSA is designed for anodizing environments. When used as a cathode, the coating undergoes an irreversible reduction reaction, resulting in drastic changes in coating volume, microcracks, and even peeling. High-frequency reversal will drastically accelerate the failure of the coating, reducing the electrode life from several years to several weeks or even days. Therefore, in order to avoid electrode damage, low-frequency reversal must be used in practical applications. As a result, scale can easily grow, densify, and firmly adhere to the electrode surface over a long period. When the electrode is reversed, polarity adjustment can only treat the surface scale and cannot effectively remove the hardened scale nuclei. In order to achieve effective cleaning, the polarity adjustment time will be extended, which will prolong the downtime and may increase the damage to the DSA. This not only leads to poor descaling effect, but the remaining rough scale surface will become a new nucleation site, making subsequent scaling faster and more stubborn, forming a vicious cycle of "the more you wash, the easier it is to scale". (4) In order to achieve the reversal, the control system needs to be equipped with a series of equipment such as an additional rectifier, which increases the complexity of the system and brings additional fault points. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings and deficiencies of the prior art and to provide an online descaling method for electrolytic cell electrodes.

[0004] An online descaling method for electrodes in an electrolytic cell, the electrolytic cell comprising a descaling unit and an electrolysis unit, the method comprising the following steps: Step S1: The electrolysis unit is controlled to operate and electrolysis products are generated; Step S2: When the descaling triggering condition is met, the descaling unit is activated, and the descaling unit generates acidic substances to descale the electrode surface. During the descaling operation, the electrolysis unit may maintain production operation or be suspended.

[0005] In one embodiment, the descaling triggering condition includes a first condition or a second condition; The first condition is that the operating time of the electrolysis unit reaches a preset time threshold; The second condition is that the efficiency of the electrolysis unit is lower than a preset efficiency threshold.

[0006] In one embodiment, the electrolysis unit and the descaling unit can be operated in an alternating mode or a simultaneous mode.

[0007] In one embodiment, when the triggering condition is a first condition, the alternating operation mode includes: (1) Control the electrolysis unit to run continuously for a first preset time, during which the descaling unit is in a closed state; (2) After the electrolysis unit has been running for the first preset time, the electrolysis unit is turned off and the descaling unit is started to run for the second preset time. During the second preset time, the electrolysis unit remains turned off. (3) After the descaling unit has been running for the second preset time, the descaling unit is turned off and the electrolysis unit is restarted.

[0008] In one embodiment, when the triggering condition is a first condition, the simultaneous operation mode includes: (1) Control the electrolysis unit to start and run continuously; (2) The descaling unit is started at the same time as the electrolysis unit is started; or, the descaling unit is started after a third preset time delay after the electrolysis unit is started. (3) The descaling unit is shut down after running for a fourth preset time, or the descaling unit continues to run during the operation of the electrolysis unit until it shuts down synchronously with the electrolysis unit; (4) If the descaling unit is shut down after running for a fourth preset time, the electrolysis unit continues to run after the descaling unit is shut down, and the descaling unit is restarted to run for the fourth preset time whenever the running time of the electrolysis unit increases by a fifth preset time.

[0009] In one embodiment, the fifth preset duration is equal to or less than the preset time threshold.

[0010] In one embodiment, when the descaling trigger condition is the second condition, the descaling unit performs a descaling operation on the electrolysis unit until the efficiency of the electrolysis module recovers to a preset efficiency threshold; or, the descaling unit performs a descaling operation on the electrolysis unit and runs for a preset fourth preset time before shutting down; or, the descaling unit performs a descaling operation on the electrolysis unit until it shuts down synchronously with the electrolysis unit.

[0011] In one embodiment, when the descaling trigger condition is the second condition, the electrolysis unit continues to operate or is suspended during descaling; if it is suspended, the electrolysis unit is restarted after descaling is completed.

[0012] In one embodiment, the preset time threshold and / or the preset efficiency threshold are adaptively adjusted based on the historical operating data of the electrolysis unit.

[0013] In one embodiment, the electrolytic cell includes a first electrode, a second electrode, and a third electrode, the first electrode and the second electrode forming the electrolytic unit, and the third electrode forming the descaling unit with the first electrode or the second electrode.

[0014] In one embodiment, the descaling unit includes a first anode and a first cathode, and the electrolysis unit includes a second anode and a second cathode.

[0015] The beneficial effects of this invention are: After the electrolysis unit is started and running, the electrolysis of water produces electrolyzed water products. During the electrolysis process, hydrogen ions are reduced to hydrogen gas at the cathode of the electrolysis unit, the concentration of hydroxide ions increases, and the water near the electrode becomes alkaline, which promotes the gradual deposition of scale (such as calcium carbonate, magnesium hydroxide, etc.) on its surface.

[0016] When the descaling trigger conditions are met, the descaling unit starts, generating acidic substances that make the water near the electrodes acidic. This acidic environment dissolves the scale formed on the electrode surface, achieving surface descaling and effectively preventing performance degradation of the electrolyzer, thus improving its overall service life. Compared to traditional electrode reversal descaling methods, the electrolysis mode of this application allows for separate control of the electrolysis reaction and the descaling reaction, reducing the system's control complexity. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart of an online descaling method for electrolytic cell electrodes according to an embodiment of this application.

[0019] Figure 2 This is a timing diagram of the operating state of an electrolytic cell according to an embodiment of this application.

[0020] Figure 3 The voltage-current characteristic curves over time are shown for continuous electrolysis operation of an electrolytic cell that does not employ the method described in this application.

[0021] Figure 4 The voltage-current variation curves of an electrolytic cell in continuous electrolytic operation in simultaneous operation mode are shown in an embodiment of the method of this application.

[0022] Figure 5 The voltage-current variation curves of an electrolytic cell in continuous electrolytic operation under alternating operation mode, according to another embodiment of the method of this application.

[0023] Figure 6 The voltage-current characteristics of an electrolytic cell that does not use the method of this application under alternating power-on and power-off modes are shown in the time curve.

[0024] Figure 7 This is a schematic diagram of the structure of an electrolytic cell according to another embodiment of this application.

[0025] Figure 8 This is a schematic diagram of the structure of an electrolytic cell according to another embodiment of this application.

[0026] Figure 9 This is a schematic diagram of the structure of an electrolytic cell according to another embodiment of this application.

[0027] Figure 10 This is a schematic diagram of the structure of an electrolytic cell according to another embodiment of this application.

[0028] Figure 11 This is a schematic diagram of the structure of an electrolytic cell according to another embodiment of this application. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0030] This invention provides an online descaling method for electrodes in an electrolytic cell. Specifically, the electrolytic cell includes a descaling unit and an electrolysis unit, such as... Figure 1 As shown, the method includes the following steps: Step S1: The electrolysis unit is controlled to operate and electrolysis products are generated; Step S2: When the descaling triggering condition is met, the descaling unit is activated, and the descaling unit generates acidic substances to descale the electrode surface. During the descaling operation, the electrolysis unit may maintain production operation or be suspended.

[0031] The beneficial effects of this invention are as follows: After the electrolysis unit is started and running, the electrolysis of water produces electrolyzed water products. During the electrolysis process, hydrogen ions are reduced to hydrogen gas at the cathode of the electrolysis unit, the concentration of hydroxide ions increases, and the water near the electrode becomes alkaline, which promotes the gradual deposition of scale (such as calcium carbonate, magnesium hydroxide, etc.) on its surface.

[0032] When the descaling trigger conditions are met, the descaling unit starts, generating acidic substances that make the water near the electrodes acidic. This acidic environment dissolves the scale formed on the electrode surface, achieving surface descaling and effectively preventing performance degradation of the electrolyzer, thus improving its overall service life. Compared to traditional electrode reversal descaling methods, the electrolysis mode of this application allows for separate control of the electrolysis reaction and the descaling reaction, reducing the system's control complexity.

[0033] Based on the above embodiments, for example, the descaling triggering condition includes a first condition or a second condition: The first condition is that the operating time of the electrolysis unit reaches a preset time threshold. That is, the descaling unit starts when the operating time of the electrolysis unit reaches the preset time threshold.

[0034] In this embodiment, the system can optionally be set to trigger conditions based on time or efficiency. In the first embodiment, the electrolytic cell performs descaling operations regularly according to time cycles, so that the electrolytic unit can receive maintenance intervention before its performance has significantly deteriorated. In the second embodiment, the electrolytic cell performs descaling operations according to the actual performance degradation, so that it can be adjusted according to different actual operating conditions, making it more flexible.

[0035] In one embodiment, the electrolysis unit and the descaling unit operate in either an alternating or simultaneous mode. That is, the electrolysis unit and the descaling unit operate in an alternating mode, or they operate simultaneously.

[0036] In one embodiment, when the triggering condition is a first condition, i.e., the operating time of the electrolysis unit reaches a preset time threshold, the alternating operation mode includes: (1) Control the electrolysis unit to run continuously for a first preset time, during which the descaling unit is in a closed state; (2) After the electrolysis unit has been running for the first preset time, the electrolysis unit is turned off and the descaling unit is started to run for the second preset time. During the second preset time, the electrolysis unit remains turned off. (3) After the descaling unit has been running for the second preset time, the descaling unit is turned off and the electrolysis unit is restarted.

[0037] In this embodiment, the ratio between the second preset duration and the first preset duration can be any value that is less than, equal to, or greater than the first preset duration. When the performance degradation of the electrolyzer is slow, a very small time ratio can be used (e.g., the second preset duration is only 1% to 5% of the first preset duration), resulting in a very low percentage of downtime for the electrolysis unit and an overall efficiency close to 100%. When the performance degradation of the electrolyzer is fast, the time ratio can be appropriately increased, such as the second preset duration being 10% of the first preset duration. In other words, in this embodiment, the descaling time ratio of the descaling unit is flexibly adjustable to adapt to the degradation characteristics of different electrolyzers. It can be specifically set according to actual working conditions (such as the influence of water quality and other conditions), making it widely applicable.

[0038] For example, the second preset duration is 1-20% of the first preset duration. For example, the second preset duration is 20-50% of the first preset duration. It can be specifically set according to the actual working conditions (such as the influence of water quality and other conditions). When the performance of the electrolyzer deteriorates slowly, a very small time ratio can be used. When the performance of the electrolyzer deteriorates quickly, the time ratio can be appropriately increased.

[0039] In one embodiment, when the triggering condition is a first condition, the simultaneous operation mode includes the following steps: (1) Control the electrolysis unit to start and run continuously; (2) The descaling unit is started at the same time as the electrolysis unit is started; or, the descaling unit is started after a third preset time delay after the electrolysis unit is started. That is, the electrolysis unit and the descaling unit are started at the same time, or the descaling unit is started after a specific time (the third preset time) of the electrolysis unit being started; (3) The descaling unit is shut down after running for a fourth preset time, or the descaling unit continues to run during the operation of the electrolysis unit until it shuts down synchronously with the electrolysis unit; that is, after the descaling unit is started, the descaling unit runs for a specific time (the fourth preset time) and then shuts down, or the descaling unit runs until the electrolysis unit shuts down and then shuts down synchronously. (4) If the descaling unit is shut down after running for a fourth preset time, the electrolysis unit continues to run after the descaling unit is shut down, and the descaling unit is restarted to run for the fourth preset time whenever the running time of the electrolysis unit increases by a fifth preset time. That is, if the descaling unit is shut down after running for a specific time (fourth preset time) in the previous step, and the electrolysis unit continues to run, the descaling unit is restarted to run for the fourth preset time every time the electrolysis unit runs for a specific time (fifth preset time).

[0040] The system repeats the above steps based on the actual operating conditions.

[0041] In this embodiment, because the electrolysis module remains running throughout the entire descaling process without downtime for maintenance, the overall production efficiency is high. Furthermore, it can continuously remove scale even before the performance of the electrolysis unit degrades or at a very low rate, preventing scale formation and maintaining a stable performance curve for the electrolysis unit, which is beneficial to the overall stability of the system.

[0042] In the above embodiments, the synchronous start-up mode of the electrolysis unit and the descaling unit allows for two main advantages. First, the descaling unit can be shut down synchronously with the electrolysis unit (i.e., full-time maintenance), providing continuous protection during the operation of the electrolysis unit. Second, the descaling unit can be shut down after a fourth preset operating time and restarted every fifth preset operating time (short-term periodic maintenance). The former is suitable for rapid degradation scenarios requiring continuous intervention, while the latter is suitable for slower degradation scenarios requiring only periodic intervention, allowing users to flexibly adjust according to their actual needs.

[0043] In one embodiment, the fifth preset duration is equal to or less than the preset time threshold. When the fifth preset duration is equal to the time threshold, the descaling cycle of the descaling unit is consistent with the triggering cycle of the first condition, achieving a unified time-based periodic maintenance and simultaneous operation. When the fifth preset duration is less than the time threshold, the descaling frequency is higher, making it suitable for various scenarios with more complex operating conditions or higher requirements for the electrolytic output water, and providing more rigorous maintenance for the electrolyzer.

[0044] In the aforementioned embodiment, the mode where the electrolysis unit starts first and the descaling unit starts later can, for example, avoid unsteady processes during the electrolysis unit's startup phase (such as reduced system load and instantaneous response capability). Alternatively, it can allow the electrolysis unit to run for a certain period, generating a certain amount of scale or accumulating decay before starting. This delayed startup allows the descaling timing of the descaling unit to match the decay state of the electrolysis unit, avoiding premature maintenance and reducing energy consumption. Furthermore, the third preset duration can be independently calibrated based on the voltage and current conditions of the electrolysis unit, water quantity, water quality, and the rate of decay accumulation, without being constrained by the first preset duration or time threshold, providing additional degrees of freedom.

[0045] In some embodiments, when the descaling trigger condition is the second condition, the electrolysis unit continues to operate or is suspended during descaling; if it is suspended, the electrolysis unit is restarted after descaling is completed. That is, when the efficiency of the electrolytic cell drops to a preset efficiency threshold, the descaling unit is started, and the electrolysis unit and the descaling unit can operate alternately or simultaneously.

[0046] In some embodiments, when the descaling trigger condition is the second condition, the descaling unit performs a descaling operation on the electrolysis unit until the efficiency of the electrolysis module recovers to a preset efficiency threshold; or, the descaling unit performs a descaling operation on the electrolysis unit and runs for a preset fourth preset time before shutting down; or, the descaling unit performs a descaling operation on the electrolysis unit until it shuts down synchronously with the electrolysis unit. That is, when the efficiency of the electrolysis cell drops to a preset efficiency threshold, the descaling unit starts and shuts down after the efficiency of the electrolysis unit recovers to the preset efficiency threshold; or, the descaling unit runs for a specific time (a fourth preset time) before shutting down; or, the descaling unit runs until the electrolysis unit shuts down and then shuts down synchronously. In the first and third cases, the electrolysis unit and the descaling unit must operate simultaneously; in the second case, they can operate alternately or simultaneously.

[0047] In the second scenario based on the above embodiments, the descaling unit shuts down after running for a fourth preset duration. Further, after the descaling unit shuts down, the electrolysis unit continues to run, and whenever the running time of the electrolysis unit increases by a fifth preset duration, the descaling unit is restarted to run for the fourth preset duration again. That is, if in the previous step the descaling unit runs for a specific duration (the fourth preset duration) and then shuts down, while the electrolysis unit continues to run, the descaling unit is restarted to continue running for the fourth preset duration every time the electrolysis unit runs for a specific duration (the fifth preset duration).

[0048] In this embodiment, the criteria for determining a decrease in electrolysis efficiency include, but are not limited to, at least one of the following: (1) The cell voltage of the electrolytic cell continues to rise and exceeds the preset threshold; (2) The operating current decreases and the effective electrolysis current efficiency decreases under rated operating conditions; (3) Energy consumption per unit output increased and the output of electrolytic products decreased.

[0049] In this embodiment, the descaling trigger condition only uses the second condition (i.e., the production efficiency of the electrolysis unit is lower than a preset efficiency threshold), and does not depend on the first condition (time threshold). In other words, the descaling unit's activation is determined by the performance degradation of the electrolysis unit, and is independent of its operating time. Because the scaling rate on the electrode surface varies under different operating conditions such as water quality, voltage, and current, for example, scaling is slower in good water quality, faster in poor water quality, slower in acidic water, and faster in alkaline water, the same electrolysis system will have different scaling rates under different operating conditions. This embodiment determines the activation of the descaling unit based on the performance degradation of the electrolysis unit, enabling descaling to accurately respond to system needs. Compared to the first condition (time-triggered mode), which requires pre-calibrating the time threshold based on operating conditions or previous experimental data, this embodiment directly detects the degradation result. Maintenance is triggered as soon as the efficiency drops below the threshold, without being limited by operating time, and can be widely adapted to various application scenarios.

[0050] In one embodiment, the preset time threshold and / or the preset efficiency threshold are adaptively adjusted based on the historical operating data of the electrolysis unit. In this embodiment, the time threshold and / or efficiency threshold are dynamically adjusted using historical operating data of the electrolysis unit (such as efficiency recovery after each descaling, time interval between two adjacent triggers, efficiency decay rate, etc.) to ensure that the descaling operation always matches the current actual performance state of the electrolysis cell, thereby extending the effective service life of the electrolysis cell.

[0051] To implement the descaling method of this application, this application also provides the structure of an electrolytic cell, and the online descaling method of the electrolytic cell electrode of this invention is applied to the electrolytic cell of this application.

[0052] In some embodiments, the electrolytic cell includes a first electrode 1, a second electrode 2, and a third electrode 4. The first electrode 1 and the second electrode 2 form the electrolysis unit, and the third electrode 4, together with the first electrode 1 or the second electrode 2, forms the descaling unit. For example, the first electrode 1 is connected to the negative terminal of an external power source, the second electrode 2 is connected to the positive terminal, and the third electrode 4 is connected to either the positive or negative terminal of the external power source. In this embodiment, if the third electrode 4 and the first electrode 1 form a descaling unit, the third electrode 4 is connected to the positive terminal; if the third electrode 4 and the second electrode 2 form a descaling unit, the third electrode 4 is connected to the negative terminal. Alternatively, the first electrode 1 is connected to the negative terminal of an external power source, the second electrode 2 is connected to the positive terminal, and the third electrode 4 is connected to either the positive or negative terminal of the external power source via a switching unit. That is, the third electrode 4 acts as both a cathode and an anode, connected in a time-sharing manner according to the control system. When the third electrode 4 acts as a cathode, the surrounding water is in an alkaline environment, and scale adheres to the surface of the cathode (i.e., the third electrode 4). When the third electrode 4 is used as the anode, the nearby water is in an acidic environment. The acidic environment can dissolve scale such as calcium carbonate, so that the third electrode 4 can achieve the purpose of surface descaling.

[0053] In other embodiments, the descaling unit in the electrolytic cell includes a first anode 5 and a first cathode 6, and the electrolysis unit includes a second anode 7 and a second cathode 8. In this embodiment, when the electrolysis unit is connected to an external power source, hydrogen ions are reduced to hydrogen gas at the cathode (second cathode) during electrolysis, increasing the hydroxide ion concentration. Therefore, the water near the second cathode becomes alkaline, promoting the gradual deposition of scale (such as calcium carbonate, magnesium hydroxide, etc.) on the surface of the second cathode. When the descaling unit is activated, the electrolysis generates acidic substances, which can dissolve scale such as calcium carbonate, thereby achieving the purpose of descaling the electrode surface.

[0054] Based on the above embodiments, for example, in a preferred embodiment, the descaling unit and the electrolysis unit are arranged adjacent to each other, and the descaling unit and the electrolysis unit are arranged with opposite polarities or alternating polarities, so that the polarities of adjacent opposite electrodes are opposite. That is, the descaling unit and the electrolysis unit are arranged opposite each other, with the first anode 5 and the second anode 7 opposite each other, and the first cathode 6 and the second cathode 8 opposite each other; or, the first anode 5 and the first cathode 8 are arranged opposite each other, and the second anode 6 and the second cathode 7 are arranged opposite each other. In this embodiment, the water near the second cathode 8 of the electrolysis unit is an alkaline environment, so scale easily adheres to the surface of the second cathode 8. When the descaling unit oxidizes the water at the first anode 5 during electrolysis to generate oxidation products (such as ozone, oxygen atoms, etc.) and hydrogen ions, the water near the electrode becomes acidic. The acidic environment can dissolve the scale formed on the cathode surface. If the electrodes of the descaling unit and the electrolysis unit are arranged with alternating polarities, the acidic substances generated by the first anode can be easily carried to the surface of the second cathode 8, which can more effectively achieve the purpose of surface descaling.

[0055] It should be understood that the number of electrolysis units and the number of descaling units in the electrolytic cell can be several, and can be designed according to actual conditions.

[0056] in, Figure 3 As a comparative example 1, the voltage-current characteristic curves over time are shown for continuous electrolytic operation of an electrolytic cell that does not employ the method of this application (i.e., without descaling). The curves clearly show that the electrolytic cell operates stably in the early stages, but as time progresses, polarization accumulates, the cell's internal resistance increases, and the current efficiency decreases. Figure 4 This is an embodiment of the method described in this application, showing the voltage-current variation curve of an electrolytic cell in continuous electrolytic operation under simultaneous operation mode. Figure 5 This is another embodiment of the method of this application, showing the voltage-current variation curve of an electrolytic cell in alternating operation mode during continuous electrolysis. Figure 6 As Figure 5 Comparative Example 2 shows the voltage-current characteristics over time of an electrolytic cell that did not employ the method of this application (i.e., no descaling), during alternating power-on and power-off cycles. In other words, in... Figure 5 During the period when the descaling unit is started (the electrolysis unit is off), Figure 6 In Comparative Example 2, the electrolysis unit was shut down and the descaling unit was not activated. Figure 4 As can be seen, the electrolytic cell using the method of this invention exhibits a significantly reduced voltage rise during operation in synchronous mode. From... Figure 5 and Figure 6 The comparison shows that, using the method of the present invention, the voltage rise during operation is significantly reduced and the current decay trend is significantly suppressed in the alternating mode.

[0057] As can be seen from the above embodiments, in alternating mode, regular descaling and short, controllable downtime of the electrolysis unit effectively delay polarization accumulation while minimizing the impact on continuous production. In simultaneous operation mode, online maintenance is possible, continuously suppressing the increase in internal resistance and the decrease in current efficiency caused by scale formation without shutdown. Overall, alternating operation mode is suitable for scenarios that are sensitive to downtime but have planned maintenance windows, while simultaneous operation mode is suitable for operating conditions requiring long-term continuous operation and with poorer water quality.

[0058] The graphs in the above embodiments are waveforms obtained by smoothing the original data to reduce high-frequency noise and highlight the overall trend. The smoothing method used is Savitzky-Golay filtering.

[0059] Among them, the above Figure 3-7In the embodiments described herein, except for the method of this application, the overall structure and operating conditions (such as current, voltage, temperature, etc.) of the electrolytic cell in the comparative examples and embodiments of the method of this application are the same.

[0060] In a preferred embodiment, such as Figure 7-11 As shown, the electrolysis unit also includes a solid electrolyte membrane 3. In this embodiment, because the descaling unit produces acidic substances, the nearby water body is in an acidic environment. Under a weakly acidic environment, the scale on the solid electrolyte membrane can also be removed simultaneously. Moreover, the acidic environment is conducive to the regeneration and repair of the solid electrolyte membrane, thus extending the service life of the electrolytic cell.

[0061] Based on the above embodiments, such as Figure 7 As shown, the descaling unit also includes a solid electrolyte membrane 3. In this embodiment, the products at both electrodes during the descaling unit reaction are hydrogen and oxygen. In embodiments without a solid electrolyte membrane, the products during the descaling unit reaction contain hypochlorous acid. Therefore, this application can be adapted to the specific application, such as when the electrolytic structure of this application is used in appliances like water dispensers, or in medical, household, or other fields, where the structure of this embodiment can be adopted, and the products are non-toxic. For industrial or other applications, a structure with or without a solid electrolyte membrane can be selected. For example, in wastewater treatment equipment, water containing hypochlorous acid is output during the descaling unit's operation. Hypochlorous acid can participate in the wastewater treatment reaction, allowing for more efficient utilization of the descaling unit's reaction.

[0062] It should be understood that the electrolytic cell of this application also includes other necessary electronic components that should have the purpose of achieving the function, such as circuit boards, and if necessary, an internal power supply. For example, the online descaling method of the electrolytic cell electrode has a conductive end, which is connected to an external power supply or an internal power supply. These will not be described in detail in this application.

[0063] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0064] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for online descaling of electrodes in an electrolytic cell, characterized in that, The electrolytic cell includes a descaling unit and an electrolysis unit, and the method includes the following steps: Step S1: The electrolysis unit is controlled to operate and electrolysis products are generated; Step S2: When the descaling triggering condition is met, the descaling unit is activated, and the descaling unit generates acidic substances to descale the electrode surface. During the descaling operation, the electrolysis unit may maintain production operation or be suspended.

2. The online descaling method for electrolytic cell electrodes according to claim 1, characterized in that, The descaling triggering condition includes a first condition or a second condition; The first condition is that the operating time of the electrolysis unit reaches a preset time threshold; The second condition is that the efficiency of the electrolysis unit is lower than a preset efficiency threshold.

3. The online descaling method for electrolytic cell electrodes according to claim 2, characterized in that, The electrolysis unit and the descaling unit can operate in either an alternating or simultaneous mode.

4. The online descaling method for electrolytic cell electrodes according to claim 3, characterized in that, When the triggering condition is the first condition, the alternating operation mode includes: (1) Control the electrolysis unit to run continuously for a first preset time, during which the descaling unit is in a closed state; (2) After the electrolysis unit has been running for the first preset time, the electrolysis unit is turned off and the descaling unit is started to run for the second preset time. During the second preset time, the electrolysis unit remains turned off. (3) After the descaling unit has been running for the second preset time, the descaling unit is turned off and the electrolysis unit is restarted.

5. The online descaling method for electrolytic cell electrodes according to claim 3, characterized in that, When the triggering condition is the first condition, the simultaneous operation mode includes: (1) Control the electrolysis unit to start and run continuously; (2) The descaling unit is started at the same time as the electrolysis unit is started, or the descaling unit is started after a third preset time delay after the electrolysis unit is started; (3) The descaling unit is shut down after running for a fourth preset time, or the descaling unit continues to run during the operation of the electrolysis unit until it shuts down synchronously with the electrolysis unit; (4) If the descaling unit is shut down after running for a fourth preset time, the electrolysis unit continues to run after the descaling unit is shut down, and the descaling unit is restarted to run for the fourth preset time whenever the running time of the electrolysis unit increases by a fifth preset time.

6. The online descaling method for electrolytic cell electrodes according to claim 5, characterized in that, The fifth preset duration is equal to or less than the preset time threshold.

7. The method for online descaling of electrolytic cell electrodes according to claim 3, characterized in that, When the descaling trigger condition is the second condition, the descaling unit performs a descaling operation on the electrolysis unit until the efficiency of the electrolysis module recovers to a preset efficiency threshold; or, the descaling unit performs a descaling operation on the electrolysis unit and runs for a preset fourth preset time before shutting down; or, the descaling unit performs a descaling operation on the electrolysis unit until it shuts down synchronously with the electrolysis unit.

8. The online descaling method for electrolytic cell electrodes according to claim 3, characterized in that, When the descaling trigger condition is the second condition, the electrolysis unit continues to operate or is suspended during the descaling process; if it is suspended, the electrolysis unit is restarted after the descaling is completed.

9. The method for online descaling of electrolytic cell electrodes according to claim 2, characterized in that, Based on the historical operating data of the electrolysis unit, the preset time threshold and / or the preset efficiency threshold are adaptively adjusted.

10. The method for online descaling of electrolytic cell electrodes according to claim 1, characterized in that, The electrolytic cell includes a first electrode, a second electrode, and a third electrode. The first electrode and the second electrode form the electrolytic unit, and the third electrode, together with the first electrode or the second electrode, forms the descaling unit.

11. The method for online descaling of electrolytic cell electrodes according to claim 1, characterized in that, The descaling unit includes a first anode and a first cathode, and the electrolysis unit includes a second anode and a second cathode.

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