Novel electrolytic tank pipeline filter and self-cleaning device

Abstract

The utility model discloses a novel electrolytic bath pipeline filter and a self-cleaning device. The novel electrolytic bath pipeline filter comprises a multi-stage filtering part, a self-cleaning system and an intelligent control system, the multi-stage filtering part comprises multi-stage filter elements arranged in the material pipeline, and the multi-stage filter elements are arranged from large to small according to the filtering particle size to form a filtering gradient; the self-cleaning system acts on the multi-stage filter element part at the same time or in a time-sharing manner on the basis of a fluid reverse recoil principle; the self-cleaning system is combined with pulsating flushing control, so that the filter element is separated from a filter cake at low loss; the multi-stage gradient filtration is adopted, impurities are efficiently and accurately intercepted, the filter elements with the particle sizes from large to small are arranged in a gradient mode, the first-stage titanium alloy filter element intercepts large particles, the second-stage polytetrafluoroethylene membrane filters tiny impurities, the efficiency is improved through graded interception, the loss of the filter elements is reduced, and the material purity and the hydrogen production quality are guaranteed. The multi-element self-cleaning technology is adopted, low-loss deep cleaning is achieved, and the self-cleaning system integrates multiple technologies such as fluid reverse backflushing, pulsating flushing, ultrasonic vibration and a pulsed electric field.

Description

Technical Field

[0001] This utility model relates to the field of electrolytic hydrogen production technology, specifically to a novel electrolytic cell pipeline filter and self-cleaning device. Background Technology

[0002] During the operation of alkaline water electrolysis hydrogen production equipment, the wet hydrogen gas generated at the cathode and anode of the electrolyzer carries a large amount of alkaline solution and may also contain impurities such as electrode coating fragments and sealing debris, which enter the subsequent separation device. Simultaneously, the alkaline solution inlet pipe connecting the separation device and the electrolyzer may also contain solid impurities due to residual metal impurities or debris from the pipe manufacturing process, leading to their entry into the separator or the electrolyzer itself. In existing technologies, Y-type filters are commonly used for filtration at the inlet and outlet (gas) pipes of the electrolyzer, but these filters have significant drawbacks:

[0003] On the one hand, the filter screen of the Y-type filter is easily clogged by impurities such as metal particles detached from the electrodes (e.g., Ni) and alkaline crystals (K2CO3). Fibrous impurities, in particular, easily entangle the filter screen, causing a sudden increase in pressure differential within the pipeline. This not only affects the stability of the electrolyzer's back pressure but also forces the equipment to operate at reduced load due to decreased flow. On the other hand, traditional stainless steel filter screens corrode at rates exceeding 0.1 mm / year in strongly alkaline environments with pH > 14, and hydrogen permeation easily triggers hydrogen embrittlement and fracture, causing filter screen structural failure and posing a risk of impurity leakage. Furthermore, existing filters require frequent shutdowns for disassembly and cleaning of the filter element, averaging once a month, with each maintenance taking no less than 6 hours. This not only increases labor costs but also interrupts hydrogen production due to equipment start-ups and shutdowns, affecting production continuity. More seriously, manual operation may lead to negligence in observing the liquid level in time, resulting in filter clogging and dry burning of the alkaline solution inside the electrolyzer, causing damage to the diaphragm and electrode plates, and potentially leading to safety accidents.

[0004] In summary, due to limitations in structural design, existing filtration technologies cannot meet the long-term stable operation requirements of alkaline water electrolysis hydrogen production systems in terms of impurity interception efficiency, material resistance, and ease of maintenance. There is an urgent need for a new type of filtration device with high-efficiency filtration, corrosion resistance, and intelligent maintenance functions to solve the problems of high clogging risk, high maintenance cost, and prominent safety hazards in traditional technologies. Utility Model Content

[0005] The purpose of this invention is to overcome the defects in the existing technology and provide a new type of electrolytic cell pipeline filter and self-cleaning device.

[0006] To achieve the above objectives, the technical solution of this utility model is as follows:

[0007] A novel electrolytic cell pipeline filter and self-cleaning device includes a multi-stage filtration section, a self-cleaning system, and an intelligent control system;

[0008] The multi-stage filtration section includes a multi-stage filter element disposed in the material pipeline, and the multi-stage filter element is arranged in descending order of filter particle size to form a filtration gradient.

[0009] The self-cleaning system is based on the principle of fluid reverse backwashing, which acts simultaneously or in stages on multiple filter elements; and the self-cleaning system is combined with pulse flushing control to achieve low filter element loss and separation from the filter cake.

[0010] The intelligent control system includes data acquisition and a central controller. The data acquisition includes monitoring the operating status data of the material pipeline and transmitting it to the central controller. The central controller triggers the self-cleaning system based on PID control or time-series logic control algorithms. Furthermore, the intelligent control system is linked with the hydrogen production process and cleans the electrolyzer in a timely manner according to its operating status.

[0011] Furthermore, the multi-stage filtration unit includes at least a primary filtration and a secondary filtration. The primary filtration uses a titanium alloy sintered filter element with a filter pore size of 80-120μm. The secondary filtration uses a polytetrafluoroethylene (PTFE) pleated membrane with a filter pore size of 3-10μm.

[0012] Furthermore, the self-cleaning system includes a high-pressure nitrogen tank, which is connected to the material outlet side of the filter element via a cleaning gas pipe. The cleaning gas pipe is equipped with a solenoid valve that controls the short-term opening and closing of the pipeline. A slag discharge pipeline is connected to the material inflow side of the filter element.

[0013] Furthermore, the multi-stage filtration unit is equipped with multiple parallel filtration branches that serve as backups for each other; each filtration branch can be independently switched and connected to the material pipeline; the multi-stage filtration unit is provided with an S-shaped continuous zigzag pipeline, and filter elements of various levels are installed on different sections of the continuous zigzag pipeline; filter elements of various levels are installed on the vertical sections of the continuous zigzag pipeline, with the inflow side of each filter element at a low position and the outflow side at a high position, and the cleaning air pipe forms a backwashing direction from top to bottom.

[0014] Furthermore, the self-cleaning system also includes an ultrasonic vibration mechanism, which includes a piezoelectric ceramic sheet. The piezoelectric ceramic sheet is attached to the non-filtration structure area of ​​the filter element, and the piezoelectric ceramic sheet converts electrical energy into ultrasonic vibration energy to peel off the particles attached to the filter element.

[0015] Furthermore, the self-cleaning system also includes a pulsed electric field mechanism, which forms a multi-field coupling and synergistic cleaning through electric field and ultrasound; the pulsed electric field mechanism is formed on the outer periphery of the filter element, the filter element is provided with a metal shell to form the positive electrode of the electric field, the inner ring of the metal shell is provided with piezoelectric ceramic to form the negative electrode of the electric field, and a sealed air gap layer is provided between the metal shell and the piezoelectric ceramic; the pulsed electric field mechanism and the ultrasonic vibration mechanism are electrically isolated from each other; the pulsed electric field mechanism and the ultrasonic vibration mechanism operate in a time-division controlled manner.

[0016] Furthermore, the primary filter element is provided with a spiral guide groove inside, and the outlet of the secondary filter element is provided with a Venturi nozzle; the material rotates in the spiral guide groove and is subjected to centrifugal force to form a swirling separation effect; the Venturi nozzle increases the material flow rate in the spiral guide groove.

[0017] Furthermore, the spiral guide channel is designed to pass through the primary filter element, and the spiral guide channel is equipped with a one-way valve on the outlet side of the primary filter element. The one-way valve allows one-way flow from the outlet side of the primary filter element to the inlet side.

[0018] Furthermore, the intelligent control system includes differential pressure monitoring and self-cleaning triggering. Differential pressure sensors are installed upstream and downstream of the multi-stage filtration unit. When the differential pressure between the upstream and downstream reaches a preset value, the intelligent control system triggers automatic cleaning.

[0019] Furthermore, the multi-stage filtration unit and self-cleaning system are located at the alkaline inlet end connected to the electrolytic cell, or at the liquid or gas phase outlet end of the gas-liquid separator; they can be located near the electrolytic cell or the gas-liquid separator as needed.

[0020] The advantages and beneficial effects of this utility model are as follows:

[0021] 1. Multi-stage gradient filtration for efficient and precise impurity interception: The filter elements are arranged in a gradient from large to small particle size. The first-stage titanium alloy filter element intercepts large particles, while the second-stage polytetrafluoroethylene membrane filters out tiny impurities. This staged interception improves efficiency, reduces filter element wear, and ensures the purity of materials and the quality of hydrogen production.

[0022] 2. Multi-faceted self-cleaning technology achieves low-loss deep cleaning. The self-cleaning system integrates multiple technologies, including fluid backflushing, pulsed rinsing, ultrasonic vibration, and pulsed electric field. Backflushing combined with pulsed rinsing allows for low-loss separation of the filter element and filter cake; ultrasonic vibration uses piezoelectric ceramic plates to convert electrical energy into vibrational energy to remove particles; and the pulsed electric field and ultrasound form a multi-field coupling for synergistic cleaning. These technologies operate in a time-sharing and sequential manner, avoiding the limitations of single cleaning methods. Deep cleaning is achieved without damaging the filter element, reducing the frequency of manual maintenance and lowering operating costs.

[0023] 3. Intelligent linkage control ensures stable system operation. The intelligent control system monitors the operating status of material pipelines in real time through data acquisition. Combined with the upstream and downstream differential pressure data fed back by differential pressure sensors, it precisely triggers the self-cleaning system based on PID control or time-sequential logic control algorithms. Furthermore, it is linked with the hydrogen production process, cleaning the electrolyzer in a timely manner according to its operating status. This avoids over-cleaning leading to energy waste, while also preventing delayed cleaning from affecting filtration efficiency. This ensures the entire system operates efficiently and stably, improving the intelligence and reliability of the electrolyzer operation. Attached Figure Description

[0024] Figure 1 This is one of the process diagrams of a novel electrolytic cell pipeline filter and self-cleaning device according to this utility model;

[0025] Figure 2 This is the second flowchart of this utility model;

[0026] Figure 3 This is a schematic diagram of the structure in this utility model where electric field and ultrasound form multi-field coupling;

[0027] Figure 4 This is a structural schematic diagram of Embodiment 5 of this utility model;

[0028] Figure 5 This is a timing diagram of the control flow of an automatic cleaning system;

[0029] In the diagram: 1. Material pipeline; 2. Multi-stage filtration section; 3. Primary filter element; 4. Secondary filter element; 5. Filtration pipeline; 6. Branch A; 7. Branch B; 8. Three-way reversing valve; 9. Cleaning air pipe; 10. Slag discharge pipeline; 11. Cyclone separator; 12. Differential pressure sensor; 13. Continuous zigzag pipeline; 14. First vertical pipe section; 15. Intermediate vertical pipe section; 16. Second vertical pipe section; 17. Metal casing; 18. Piezoelectric ceramic; 19. Air gap layer; 20. Spiral guide channel; 21. Venturi nozzle; 22. One-way valve. Detailed Implementation

[0030] The specific embodiments of this utility model will be further described below with reference to examples. These examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0031] Example 1:

[0032] A novel electrolytic cell pipeline filter and self-cleaning device are disclosed. In practical use, this device can be installed on the liquid inlet pipe of the electrolytic cell, or on the liquid outlet or gas outlet pipe of the electrolytic cell. In both cases, it can filter the material in the pipeline. The difference is that the filtration structure set in this embodiment includes a multi-stage filtration section 2. It can be understood that the number of filtration stages is not limited. This embodiment only takes a two-stage filtration as an example. Specifically, the multi-stage filtration section 2 includes a primary filtration and a secondary filtration. The primary filtration uses a titanium alloy sintered filter element, and its primary filter element 3 has a filtration pore size of 80-120μm. The secondary filtration uses a polytetrafluoroethylene (PTFE) pleated membrane, and its secondary filter element 4 has a filtration pore size of 3-10μm. The filter elements on the two filtration stages have different pore sizes, filtering from coarse to fine, thus forming a gradient filtration module with the overall multi-stage filter cloth. In actual use, the pore size of the first stage can be 100μm, which can intercept particles >80μm, such as electrode fragments; while the second stage is used for fine filtration. In this embodiment, a polytetrafluoroethylene (PTFE) pleated membrane is specifically designed with a pore size of 5μm. This second-stage fine filtration is used to capture microcrystals and fine impurities, with a filtration efficiency of ≥99.5%.

[0033] The specific process pipeline design in this embodiment can be as follows: Figure 1 As shown, two parallel multi-stage filtration pipes 5 are installed on the material pipeline 1. The parallel filtration pipes 5 can serve as backups for each other, and each filtration pipe 5 can be independently switched to connect to the material pipeline 1. Specifically, the two parallel filtration pipes 5 on the upper and lower sides are designated as branch A6 and branch B7. Branches A and B are respectively equipped with primary filtration and secondary filtration. Three-way reversing valves 8V1 and V2 are installed at the front and rear ends of the primary and secondary filtration pipes 5 on branches A and B, respectively. In actual use, the switching between branches A6 and B can be achieved by switching the three-way valves V1 and V2. In actual use, any one filtration pipe 5 can be used, while the other pipe can be in the cleaning stage, thus allowing for mutual replacement. During normal operation, one set of branches is working while the other is on standby. When the working branch needs cleaning, it is switched to the standby branch to achieve online cleaning without stopping the machine. Furthermore, this device also includes a self-cleaning system, which acts simultaneously or sequentially on multiple filter elements based on the principle of fluid reverse backflushing. The self-cleaning system, combined with pulsed flushing control, ensures low filter element loss and separation from the filter cake. Specifically, in this embodiment, the power source for reverse backflushing is a high-pressure nitrogen tank with a pressure of 0.5~1.0 MPa. The high-pressure nitrogen tank is connected to the material outlet side of the filter element via a cleaning air pipe 9. The cleaning air pipe 9 is equipped with solenoid valves N1 and N3 for short-term opening and closing of the control pipeline. A slag discharge pipe 10 is connected to the material inflow side of the filter element. As an improvement, the slag discharge pipe 10 can also be connected to a cyclone separator 11 to separate solid impurities and waste liquid, avoiding secondary pollution. Figure 1 As shown, solenoid valves N1 and N3 are connected to the downstream of branch A6 and branch B7 respectively, and slag discharge pipes and corresponding solenoid valves N2 and N4 are respectively installed upstream of branch A6 and branch B7. Specifically, solenoid valves N1 and N2 control high-pressure nitrogen to enter branch A for backflushing and automatic cleaning; correspondingly, solenoid valves N3 and N4 control high-pressure nitrogen to enter branch B for backflushing and automatic cleaning of branch B7. It can be understood that the operation of the solenoid valves needs to be coordinated with the operation of the directional valve group to achieve the cleaning of the parallel pipelines. Furthermore, the directional valve group of each branch can be an automatic control valve to realize the automatic operation of this system.

[0034] The specific usage process is as follows: dual branches are connected in parallel for standby. Branches A6 and B7 are simultaneously connected to the main material pipeline 1, and a three-way valve controls one for operation and one for standby. If branch A6 is running, branch B7 is on standby. It also includes an intelligent control system, which includes data acquisition. The data acquisition includes differential pressure sensors 12 installed upstream and downstream of the branches of the multi-stage filtration section 2. The intelligent control system triggers automatic cleaning when the upstream and downstream pressure difference reaches a preset value. Specifically, the differential pressure sensor 12 ΔP_A monitors the pressure difference before and after filtration in branch A6. Normal filtration occurs when ΔP_A < 15 kPa. The fluid flow is: material pipeline 1 inlet → branch A6 primary coarse filtration → branch A6 secondary fine filtration → material pipeline 1 outlet. Self-cleaning trigger and branch switching: trigger condition: when ΔP_A ≥ 15 kPa, the PLC determines that the filter element in branch A6 is clogged and initiates the following process:

[0035] Step 1: Switch to the backup branch and output a signal to the three-way valves V1 and V2 to switch to branch B, so that the material fluid is cut into branch B7 for filtration, ensuring that the main process is not interrupted.

[0036] Step 2: Start the self-cleaning function of branch A6, open the slag discharge valve N2 at the outlet of branch A6; switch to the sewage discharge mode, disconnect from the main pipeline, and connect the cyclone separator 11.

[0037] When the solenoid valve N1 is triggered to open, high-pressure nitrogen gas (0.5~1.0MPa) is injected in reverse from the fine filter outlet of branch A6, in the direction of fine filtration → coarse filtration. At the same time, the pulse control module adjusts the backwash pulse width (0.1 seconds) and frequency (1~5Hz). Under short-term backwash, the filter cake can be effectively flushed off, and the filter element can also be avoided from being damaged by long-term high-pressure backwash.

[0038] Specifically, the self-cleaning system can be controlled by an intelligent control system to automatically clean the multi-stage filtration section 2. The intelligent control system includes data acquisition and a central controller. The data acquisition includes monitoring the operating status data of the material pipeline 1 and transmitting it to the central controller. The central controller triggers the self-cleaning system based on PID control or time-sequential logic control algorithms. Furthermore, the intelligent control system is linked with the hydrogen production process and cleans the electrolyzer in a timely manner according to its operating status. Data acquisition layer: The differential pressure sensor 12 (range 0~100kPa) monitors the inlet and outlet pressure difference ΔP of the filtration device to obtain real-time operating status data of the material pipeline 1, such as flow rate and pressure fluctuations, and transmits it to the central controller. In actual use, additional sensors such as temperature sensors can be added to improve the ability to collect parameters within the material pipeline 1. The central controller employs a PLC or industrial computer, with built-in PID control algorithms or sequential logic control algorithms. Based on preset thresholds, such as in this embodiment where a pressure difference ΔP > 15 kPa, the self-cleaning system is triggered. In this embodiment, high-pressure nitrogen backflushing is used. Those skilled in the art can also vary the cleaning method according to actual conditions to achieve pipeline cleaning. Simultaneously, it communicates with the DCS system via the Modbus protocol to upload data such as filtration efficiency, pressure difference, and maintenance warnings. Further, it can include linkage control, which is linked to the hydrogen production process, such as the electrolyzer's operating status, adjusting the self-cleaning timing based on parameters such as electrolyzer load and alkali concentration to avoid affecting hydrogen production efficiency.

[0039] The core control logic is as follows, and its control flow timing is as follows: Figure 5 As shown, the system triggers actions based on a set threshold. When ΔP exceeds a set value, such as 15 kPa, the filter element is determined to be clogged, and the backflushing process is automatically initiated. Combined with timing control and backflushing pulse width (e.g., 0.1 seconds, frequency 1~5 Hz) and / or superimposed ultrasonic vibration cleaning (frequency 20~40 kHz), low-loss cleaning is achieved. Furthermore, it integrates with a factory-level monitoring system via the Modbus protocol for system integration, enabling data visualization and remote operation and maintenance.

[0040] Data acquisition and processing include monitoring parameters and data transmission. The monitoring data includes a differential pressure parameter ΔP: the pressure difference between the inlet and outlet of the filter device, directly reflecting the degree of filter element clogging. Optionally, auxiliary parameters such as flow rate can be added. The flow rate of the fluid in the pipeline is monitored using an electromagnetic flow meter, and the clogging status is cross-verified with the differential pressure data. For example, if the flow rate decreases by more than 10% and ΔP increases, cleaning is intensified. Parameters such as the state of the electrolytic cell can also be monitored. Data such as the electrolytic cell current, voltage, and alkali concentration are obtained via the Modbus protocol to determine the system load. For example, self-cleaning is triggered during low-load periods. The data transmission includes: the differential pressure sensor 12 transmits data to the central controller via a 4~20mA analog signal or an RS485 bus, with a sampling frequency of ≥1 time per second.

[0041] Furthermore, it can be linked with the process flow, such as cleaning during low-load periods: by acquiring electrolyzer operating data through the DCS, self-cleaning can be automatically triggered when the electrolyzer current is <30% of the rated load, such as during off-peak hours at night, reducing the impact on hydrogen production efficiency. Linkage with alkali concentration compensation: if an abnormal alkali concentration is detected, such as >30%, it can be predicted that the risk of crystallization is increasing, and the backflushing frequency can be increased accordingly, such as adjusting from once a month to once a week.

[0042] The shell of material pipeline 1 is made of Hastelloy C276, which is resistant to alkali corrosion and hydrogen embrittlement, with a wall thickness of ≥3mm. It features a rupture disc with an operating pressure of 1.5 times the working pressure, linked to a hydrogen sensor. It automatically releases pressure when the concentration exceeds 1%, enhancing safety.

[0043] Example 2:

[0044] In the aforementioned embodiments, a multi-stage filtration unit 2 is provided with multiple backup filtration branches connected in parallel; each filtration branch is independently switched and connected to the material pipeline 1; its backwashing direction is a backwashing sequence of passing through the secondary filter and the primary filter in sequence. The secondary filter intercepts impurities with relatively small particle sizes and can penetrate the primary filter during backwashing to achieve the backwashing effect. However, if the filter cake clumps or other issues cause small particles of impurities to combine into relatively large impurities, this continuous backwashing effect is not ideal, and some impurities will be intercepted between the primary filter and the secondary filter. Over time, the backwashing effect will also decrease.

[0045] As an improvement, in this embodiment, the multi-stage filtration section 2 of branch A6 and branch B7 is designed as an S-shaped continuous zigzag pipeline 13, and filter elements of each stage are set on different pipe sections of the continuous zigzag pipeline 13; filter elements of each stage are set on the vertical pipe section of the continuous zigzag pipeline 13, and the inflow side of each stage filter element is at a low position and the outflow side is at a high position, and the cleaning air pipe 9 forms a backwashing direction from top to bottom.

[0046] Specifically, the S-shaped continuous zigzag pipeline 13 of branches A and B includes a first vertical pipe section 14, an intermediate vertical pipe section 15, a second vertical pipe section 16, and a horizontal pipe section connecting the vertical pipe sections to form branches. First-stage coarse filtration section: First vertical pipe section 14, with the first-stage filter element 3 installed in the middle of the pipe section, the inlet side located at the bottom of the pipe section, and the outlet side located at the top of the pipe section; then it passes through a horizontal pipe section and connects to the top of the intermediate vertical pipe section 15, and the bottom of the intermediate vertical pipe section 15 connects to the bottom of the second vertical pipe section 16; Second-stage fine filtration section: Second vertical pipe section 16, with the second-stage filter element 4 installed in the middle of the pipe section, the inlet side located at the bottom of the pipe section (low position), and the outlet side located at the top of the pipe section (high position).

[0047] In this embodiment, the layout of the cleaning air tube 9 is as follows: Figure 2As shown, the backwash inlet of the primary filter element 3 is connected to the top of the first vertical pipe section 14, with the airflow direction from top to bottom, opposite to the filtration direction. Similarly, the backwash inlet of the secondary filter element 4 is connected to the top of the second vertical pipe section 16, with the airflow direction also from top to bottom. Slag discharge pipes 10 are respectively installed at the bottom of the first vertical pipe section 14 and the second vertical pipe section 16 and connected to the cyclone separator 11. This achieves independent backwashing of the primary filter element 3 and the secondary filter element 4. The backwash airflow pushes the agglomerated impurities downwards along the vertical pipe section, in the same direction as gravity, enhancing the flushing effect on the impurities deposited in the "horizontal section between filter elements" in Example 1. In traditional straight pipe horizontal sections, impurities are easily lifted and retained by the airflow.

[0048] Specifically, the backflushing control process for the S-shaped pipeline is as follows:

[0049] 1. During normal filtration, valve status: Valves V1 and V2 are switched to branch A and opened; backflush solenoid valves N1 and N2 are closed; and drain valves V3-V5 are closed. Fluid path: Alkali / gas from inlet → bottom of first vertical pipe section 14 → from bottom to top through primary filter element 3 (intercepting particles >80μm) → middle vertical pipe section 15 → bottom of second vertical pipe section 16 → from bottom to top through secondary filter element 4 (capturing impurities ≤5μm) → outlet into the main pipeline.

[0050] 2. Backwashing Cleaning Stage (taking branch A6 as an example): Triggering conditions: Differential pressure sensor 12 detects ΔP > 15 kPa at the inlet and outlet of the second vertical pipe section 16 (secondary filter element 4 is clogged) or ΔP > 10 kPa at the inlet and outlet of the first vertical pipe section 14 (primary filter element 3 is clogged). Control process: Branch switching in parallel system: Close branch A6 and switch to branch B7, fluid is switched to the standby branch, and the main process is maintained. This system can then control the flushing of primary filter element 3 or secondary filter element 4 separately via valves (control valves need to be added for each level of filter element); alternatively, solenoid valve N1 can be used to control the backwashing of both filter elements simultaneously. During flushing, the filter cake on the filter element falls to the bottom of the vertical pipe under the action of pressure and gravity, enters the slag discharge pipe 10, and then enters the cyclone separator 11.

[0051] The top-down backwash direction, combined with gravity, increases the flushing force on blocky impurities deposited in the "horizontal section between filter elements" by 50%, avoiding the drawback of airflow "lifting up impurities" in traditional horizontal pipelines.

[0052] Example 3:

[0053] Furthermore, to improve the self-cleaning effect, the self-cleaning system in this embodiment also includes an ultrasonic vibration mechanism. This mechanism comprises 18 piezoelectric ceramic pieces, which are attached to the non-filtration structure area of ​​the filter element. These piezoelectric ceramic pieces convert electrical energy into ultrasonic vibration energy to peel off particles adhering to the filter element. Specifically, the filter element is divided into a filtration functional area and a non-filtration structural area, with areas serving only a supporting and fixing function, such as the inner layer of the titanium alloy sintered filter element, the filter element end caps, and the support frame. During installation, the 18 piezoelectric ceramic pieces must not be attached to the surface of the filtration functional area to avoid obstructing the filter pores or causing the ceramic pieces to detach due to fluid erosion, thus affecting the filtration efficiency.

[0054] The 18 piezoelectric ceramic discs should be attached to the surface of the metal support structure to efficiently transfer vibrational energy to the filtration functional area via solid-state conduction, reducing energy loss. The vibration frequency of the ceramic discs (20-40kHz) needs to match the natural frequency of the filter element support structure to induce a resonance effect and enhance impurity removal. For example, the natural frequency of the titanium alloy support layer is approximately 25kHz; selecting 25kHz ceramic discs can achieve resonance.

[0055] In one implementation, the inner side of the filter element support layer is annularly fitted, suitable for cylindrical filter elements. An annular groove, 2mm deep and 5mm wide, is machined on the inner wall of the titanium alloy support layer. Eighteen piezoelectric ceramic pieces, 1mm thick, with an outer diameter matching the groove, are embedded within the groove and fixed with a high-temperature resistant adhesive, such as epoxy resin. This method is suitable for primary coarse filtration with a titanium alloy support layer or secondary fine filtration with a metal mesh support layer.

[0056] In another embodiment, a circular groove is machined at the center of the inner side of the upper and lower end caps of the filter element. The ceramic sheet is connected to the bottom of the groove via a spring pin, allowing for fine adjustment of the pre-tightening force. The vibration transmission mechanism is as follows: ceramic sheet vibration → end cap resonance → vibration wave transmission along the filter element axis → longitudinal tensile vibration generated by the folded membrane, which disrupts the adhesion of the filter cake.

[0057] Example 4:

[0058] Furthermore, the self-cleaning system also includes a pulsed electric field mechanism, which forms a multi-field coupling and synergistic cleaning through electric field and ultrasound; the pulsed electric field mechanism is formed on the outer periphery of the filter element, the filter element is provided with a metal shell 17 to form the positive electrode of the electric field, and a piezoelectric ceramic 18 is provided in the inner ring of the metal shell 17 to form the negative electrode of the electric field, and a sealed air gap layer 19 is provided between the metal shell 17 and the piezoelectric ceramic 18; the pulsed electric field mechanism and the ultrasonic vibration mechanism are electrically isolated from each other; the pulsed electric field mechanism and the ultrasonic vibration mechanism operate in a time-division controlled manner.

[0059] Specifically, such as Figure 3As shown, the outermost layer is a Hastelloy C276 shell, serving as the positive electrode of the electric field and also as the filter housing, providing corrosion resistance and resistance to hydrogen embrittlement. The middle layer is an air gap layer 19, which is insulated and sealed, forming the space for the electric field to function. The inner layer consists of 18 piezoelectric ceramic pieces (with a conductive layer), serving as the negative electrode of the electric field and also providing ultrasonic vibration functionality. The surface of the ceramic pieces is coated with an indium tin oxide (ITO) conductive layer. The core layer is the filter element, which performs the filtration function.

[0060] Electric field pretreatment: A pulsed electric field charges particles adhering to the filter element surface, such as metal microparticles and colloids; the adhesion between particles and the filter membrane is weakened through electrophoresis, with the electric field force greater than the van der Waals force. Ultrasonic peeling: The subsequent ultrasonic vibration utilizes the acoustic flow and cavitation effects to accelerate the detachment of charged particles from the filter membrane under mechanical force. Simultaneously, the residual charge in the electric field enhances the electrostatic repulsion between particles, preventing secondary aggregation. This creates a synergistic effect between the electric field and ultrasound.

[0061] Electric field input: The metal casing 17 is bolted to the positive terminal of the pulse power supply, and the conductive layer of the piezoelectric ceramic 18 is connected to the negative terminal of the power supply via a BNC interface. Ultrasonic input: The other electrode of the piezoelectric ceramic 18 (on the non-conductive layer side) is connected to an ultrasonic drive power supply with an adjustable frequency of 20~40kHz. Sealing: O-rings (fluororubber material) are used between each layer to withstand pressure ≥1.0MPa, preventing alkaline solutions from seeping into the air gaps.

[0062] The single-cycle cleaning steps are as follows:

[0063] Close the main fluid valve: cut off the filter element inlet and outlet, and isolate the branch line to be cleaned.

[0064] Pulsed electric field effect: The power supply outputs a 500V, 100Hz pulse for 2 seconds, which charges the particles on the filter membrane surface. For example, Ni²+ becomes positively charged and migrates to the negative electrode piezoelectric ceramic 18.

[0065] Ultrasonic vibration effect: Immediately start 25kHz ultrasonic vibration for 5 seconds, use vibration energy to detach charged particles, and carry them away by backflushing nitrogen gas (0.5MPa).

[0066] Repeated cycle: The electric field-ultrasonic process is repeated 3 times to enhance the cleaning effect.

[0067] Resumption of operation: Open the main fluid valve and put the filter element back into use.

[0068] Example 5:

[0069] The first-stage filter element 3 has a spiral guide groove 20 inside, and the outlet of the second-stage filter element 4 is equipped with a Venturi nozzle 21; the material rotates in the spiral guide groove 20 and is subjected to centrifugal force to form a swirling separation effect; the Venturi nozzle 21 increases the flow rate of the material in the spiral guide groove 20.

[0070] Specifically, such as Figure 4 As shown, this embodiment features a two-stage filter cartridge series structure. The first-stage filter cartridge 3 has a spiral groove with equal pitch P=80mm, groove depth h=5mm, and spiral angle α=30°, designed along the filter cartridge axis. During forward filtration, the material flows along the spiral groove, generating a centrifugal force field with a centrifugal acceleration ≈100g, causing particles >50μm to migrate towards the outer wall of the filter cartridge, achieving pre-separation.

[0071] The Venturi nozzle 21 is located at the outlet end of the secondary filter element 4, 20mm downstream of the fine filter membrane (PTFE pleated membrane), ensuring accelerated fluid flow after filtration. The contraction section has a cone angle θ = 45° and a minimum inner diameter d = 40-50mm, forming a contraction ratio of approximately 2:1 with the filter element's inner diameter of 80mm. The diffuser section has a cone angle β = 15° and a length L = 80mm, with an outlet inner diameter consistent with the filter element. During forward filtration, the clean fluid generates a Venturi effect through the nozzle throat, increasing the flow velocity from 1m / s to 3m / s, creating a negative pressure zone with a pressure drop of ≈20kPa. This draws pre-separated impurities from the spiral grooves of the primary filter element 3 towards the outlet, preventing deposition and clogging. During reverse flushing, the nozzle throat accelerates the backflow, thereby enhancing the scouring kinetic energy against the inner wall of the spiral grooves.

[0072] The spiral guide channel 20 is designed to pass through the primary filter element 3, and a one-way valve 22 is provided on the outlet side of the primary filter element 3. The one-way valve 22 allows unidirectional flow from the outlet side of the primary filter element 3 to the inlet side. The one-way valve 22 at the outlet of the guide channel is a diaphragm type with an opening pressure of 0.05MPa. It only allows backwash fluid to flow from the outlet to the inlet and closes during forward filtration to prevent pre-separated impurities from flowing back into the fine filtration area.

[0073] Specifically, in the forward filtration process, the fluid flow path is as follows: material flows from the inlet of primary filter element 3 → spiral guide channel 20 (cyclone separation, >50μm particles adhere to the wall and deposit) → coarse filter membrane (intercepts >80μm particles) → one-way valve 22 (closes) → inlet of secondary filter element 4 → fine filter membrane (captures ≤5μm impurities) → venturi nozzle 21 (flow rate increases to 3m / s) → outlet.

[0074] Cyclone separation effect: The tangential velocity of the fluid in the spiral groove reaches 2m / s, and the centrifugal force causes 90% of Ni particles with a diameter >60μm to migrate to the wall, reducing the load on the fine filtration membrane.

[0075] Backwashing process: When differential pressure sensor 12 detects that the differential pressure has reached the set value, the one-way valve 22 opens under the action of differential pressure during backwashing. High-pressure nitrogen (0.8MPa) flows from the outlet of secondary filter element 4 → Venturi nozzle 21 → secondary filter element 4 fine filter membrane → primary filter element 3 outlet → one-way valve 22 (the membrane is lifted by pressure and opens) → spiral guide channel 20 (backwashing).

[0076] Cyclone Backwash Enhancement: The backwash airflow flows counter-currently along the spiral groove, using the spiral lift to axially push deposited impurities (such as electrode fragments and K2CO3 clumps) into the slag discharge pipe on the inlet side of the primary filter element 3. The high-speed airflow generated by the Venturi nozzle 21 forms a rotating air knife in the spiral groove, washing away the filter cake attached to the groove wall, improving the cleaning efficiency by 40% compared to traditional straight pipe backwash. Sludge Discharge and Reset: Impurities are separated by the cyclone separator 11, and nitrogen is recycled. After cleaning, the one-way valve 22 automatically resets. The diaphragm of the one-way valve 22 closes under positive pressure during forward filtration.

[0077] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A novel electrolytic cell pipeline filter and self-cleaning device, characterized in that, Includes multi-stage filtration, self-cleaning system, and intelligent control system; The multi-stage filtration section includes a multi-stage filter element disposed in the material pipeline, and the multi-stage filter element is arranged in descending order of filter particle size to form a filtration gradient. The self-cleaning system is based on the principle of fluid reverse backwashing, which acts simultaneously or in stages on multiple filter elements; and the self-cleaning system is combined with pulse flushing control to achieve low filter element loss and separation from the filter cake. The intelligent control system includes differential pressure sensors, which are installed upstream and downstream of the multi-stage filtration section. The differential pressure sensors are electrically connected to the central controller. The central controller is electrically connected to the self-cleaning system to control the operation of the self-cleaning system.

2. The novel electrolytic cell pipeline filter and self-cleaning device according to claim 1, characterized in that, The multi-stage filtration unit includes at least a primary filtration and a secondary filtration. The primary filtration has a filter element pore size of 80-120μm, and the secondary filtration has a filter element pore size of 3-10μm.

3. The novel electrolytic cell pipeline filter and self-cleaning device according to claim 1, characterized in that, The self-cleaning system includes a high-pressure nitrogen tank, which is connected to the material outlet side of the filter element via a cleaning gas pipe. The cleaning gas pipe is equipped with a solenoid valve that controls the short-term opening and closing of the pipeline. A slag discharge pipeline is connected to the material inflow side of the filter element.

4. A novel electrolytic cell pipeline filter and self-cleaning device according to claim 3, characterized in that, The multi-stage filtration unit is provided with an S-shaped continuous zigzag pipeline, and filter elements of various levels are installed on different sections of the continuous zigzag pipeline; filter elements of various levels are installed on the vertical sections of the continuous zigzag pipeline, with the inflow side of each filter element at a low position and the outflow side at a high position, and the cleaning air pipe forms a backwashing direction from top to bottom.

5. A novel electrolytic cell pipeline filter and self-cleaning device according to claim 1, characterized in that, The self-cleaning system also includes an ultrasonic vibration mechanism, which includes a piezoelectric ceramic sheet. The piezoelectric ceramic sheet is attached to the non-filtration structure area of ​​the filter element and converts electrical energy into ultrasonic vibration energy to peel off the particles attached to the filter element.

6. A novel electrolytic cell pipeline filter and self-cleaning device according to claim 5, characterized in that, The self-cleaning system also includes a pulsed electric field mechanism, which uses electric field and ultrasound to form multi-field coupling for synergistic cleaning. The pulsed electric field mechanism is formed on the outer periphery of the filter element. The filter element is provided with a metal shell to form the positive electrode of the electric field, and a piezoelectric ceramic is provided in the inner ring of the metal shell to form the negative electrode of the electric field. A sealed air gap layer is provided between the metal shell and the piezoelectric ceramic. The pulsed electric field mechanism and the ultrasonic vibration mechanism are electrically isolated from each other. The pulsed electric field mechanism and the ultrasonic vibration mechanism operate in a time-division controlled manner.

7. A novel electrolytic cell pipeline filter and self-cleaning device according to claim 2, characterized in that, The primary filter element has a spiral guide groove inside, and the outlet of the secondary filter element is equipped with a Venturi nozzle; the material rotates in the spiral guide groove and is subjected to centrifugal force to form a swirling separation effect; the Venturi nozzle increases the flow rate of the material in the spiral guide groove.

8. A novel electrolytic cell pipeline filter and self-cleaning device according to claim 7, characterized in that, The spiral guide channel is designed to pass through the primary filter element, and a one-way valve is provided on the outlet side of the primary filter element. The one-way valve allows one-way flow from the outlet side of the primary filter element to the inlet side.

9. A novel electrolytic cell pipeline filter and self-cleaning device according to claim 1, characterized in that, The intelligent control system includes differential pressure monitoring and self-cleaning triggering. Differential pressure sensors are installed upstream and downstream of the multi-stage filtration section. When the differential pressure between the upstream and downstream reaches a preset value, the intelligent control system triggers automatic cleaning.

10. A novel electrolytic cell pipeline filter and self-cleaning device according to claim 1, characterized in that, The multi-stage filtration unit and self-cleaning system are located at the alkaline inlet end connected to the electrolytic cell, or at the liquid or gas phase outlet end of the gas-liquid separator.

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