Hydrogen fluoride production process water recycling apparatus

Abstract

The utility model relates to hydrogen fluoride production supporting environmental protection equipment technical field, concretely is hydrogen fluoride production process water circulation equipment, including grading pretreatment, intelligent purification reuse, anticorrosion transmission and full link monitoring module. The sand trap is equipped with grating and inclined sand discharge plate, realizes the efficient separation of impurities, the pH adjusting box is built -in stirring paddle with pH sensor, ensures water quality stability. The multi -media filter box is equipped with quartz sand and activated carbon layer, combines bottom titanium -based lead dioxide electrochemistry defluorination unit, effectively reduces the fluoride ion concentration, and the reuse water tank is equipped with liquid level and water quality sensor, realizes the reuse control. The anticorrosion transmission module adopts the fluorine plastic pipeline and fluorine lining centrifugal pump of inner coating polytetrafluoroethylene, cooperates the corrosion inhibitor dosing, promotes the system acid corrosion resistance, and the full link monitoring module integrates flow, corrosion rate and fluoride ion concentration sensor, realizes real -time monitoring and intelligent control of operating parameter by PLC controller.

Description

Technical Field

[0001] This utility model relates to the technical field of environmental protection equipment for hydrogen fluoride production, specifically to water circulation equipment for hydrogen fluoride production processes. Background Technology

[0002] Traditional water treatment equipment is mostly made of ordinary carbon steel or stainless steel, which is highly susceptible to corrosion in strongly acidic, fluoride-containing environments. This leads to problems such as pipe perforation, pump damage, and high leakage risks, resulting in high maintenance costs and short service life. Conventional pretreatment processes typically only include simple grit chambers, lacking effective mechanisms for removing large suspended solids and sandy impurities, easily causing clogging of subsequent filtration systems. pH adjustment relies heavily on manual dosing and experience-based control, lacking real-time monitoring and automatic feedback, resulting in poor adjustment accuracy and affecting subsequent fluoride removal efficiency.

[0003] In terms of advanced treatment, traditional processes commonly employ chemical precipitation for fluoride removal, which suffers from problems such as high reagent consumption, the generation of large amounts of sludge, and difficulty in achieving acceptable fluoride ion concentrations in the effluent. While some systems have incorporated membrane treatment technology, frequent replacements and high operating costs are incurred when dealing with high-salt and highly corrosive water. Furthermore, existing equipment generally lacks real-time monitoring of the entire process operation, making it difficult to achieve coordinated control of key parameters such as corrosion rate, fluoride ion concentration, and flow rate. The systems have low levels of intelligence and cannot meet the safety, environmental protection, and automated management requirements of modern factories. Utility Model Content

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this utility model provides a water circulation device for hydrogen fluoride production processes.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, this utility model provides the following technical solution: The hydrogen fluoride production process water circulation equipment of this utility model includes:

[0008] The graded pretreatment module includes a grit chamber and a pH adjustment tank. The grit chamber is equipped with a grid on the top and an inclined sand discharge plate on the bottom. The grit chamber is connected to the pH adjustment tank, which is equipped with a liquid inlet.

[0009] The intelligent purification and reuse module includes a multi-media filter box, an electrochemical defluorination unit, and a reuse water tank. The multi-media filter box is filled with a quartz sand layer and an activated carbon layer. The electrochemical defluorination unit is installed at the bottom of the multi-media filter box. The multi-media filter box is connected to the reuse water tank through a pipe. The reuse water tank is equipped with a drain pipe and an electric valve. The pH adjustment tank is connected to the multi-media filter box through an outlet pipe. The outlet pipe is equipped with a water pump and an outlet valve. The bottom of the multi-media filter box is equipped with a sewage pipe and a sewage valve.

[0010] Preferably, it also includes a corrosion-resistant transmission module, which includes a fluoroplastic pipe, a fluoropolymer-lined centrifugal pump, and a corrosion inhibitor dosing hopper. The inner wall of the fluoroplastic pipe is coated with polytetrafluoroethylene. The fluoropolymer-lined centrifugal pump is connected in series with the fluoroplastic pipe. A flow valve is provided at the bottom of the dosing hopper. The two ends of the fluoroplastic pipe are respectively connected to a sedimentation tank and a pH adjustment tank.

[0011] More preferably, the pH adjustment tank is equipped with a stirring paddle and a pH sensor, and a stirring motor is installed on the top of the pH adjustment tank. The output end of the stirring motor passes through the pH adjustment tank and is connected to the stirring paddle.

[0012] Preferably, the electrochemical defluorination unit uses a titanium-based lead dioxide electrode, and the recycled water tank is equipped with a liquid level sensor and a water quality sensor.

[0013] Preferably, it also includes a full-link monitoring module, which is electrically connected to the graded pretreatment module, the anti-corrosion transmission module, and the intelligent purification and reuse module, respectively. The full-link monitoring module includes a flow sensor, a corrosion rate sensor, a fluoride ion concentration detector, and a PLC controller.

[0014] More preferably, the flow sensor is installed at the inlet of the fluoroplastic pipe, the corrosion rate sensor is attached to the outer wall of the fluoroplastic-lined centrifugal pump, the fluoride ion concentration detector is installed at the top of the fluoroplastic pipe and at the outlet of the water outlet pipe, and the PLC controller is electrically connected to the level sensor, water quality sensor, flow sensor, corrosion rate sensor, fluoride ion concentration detector, fluoroplastic-lined centrifugal pump, water pump, water outlet valve, sewage valve, stirring motor, electric valve and pH sensor.

[0015] Preferably, the top of the sedimentation tank and the multi-media filter box is provided with a side frame, the side of the grid is placed on the side frame of the sedimentation tank, the side frame of the multi-media filter box is provided with a filter screen frame, and the quartz sand layer and the activated carbon layer are laid inside the filter screen frame.

[0016] (III) Beneficial Effects

[0017] Compared with the prior art, this utility model provides a water circulation device for hydrogen fluoride production process, which has the following beneficial effects:

[0018] This technical solution utilizes the synergistic effect of the grit chamber and pH adjustment tank in the staged pretreatment module to effectively remove large particulate impurities and stabilize the pH value of the water. The design of the bar screen and inclined sand discharge plate facilitates the interception of suspended solids and automatic sand discharge, improving pretreatment efficiency. The intelligent purification and reuse module employs a multi-media filtration system combining quartz sand and activated carbon with electrochemical defluorination technology. It utilizes a titanium-based lead dioxide electrode to efficiently remove fluoride ions, significantly improving effluent quality and ensuring that the reused water meets standards. The reused water tank is equipped with level and water quality sensors to achieve automated control and real-time monitoring.

[0019] The corrosion-resistant transmission module uses fluoroplastic pipes with an inner PTFE coating and a fluoropolymer-lined centrifugal pump, providing excellent acid corrosion resistance and extending equipment lifespan. A corrosion inhibitor dosing hopper, combined with a flow valve, allows for precise dosing of the agent, further inhibiting system corrosion. The end-to-end monitoring module integrates sensors for flow rate, corrosion rate, and fluoride ion concentration, all centrally controlled by a PLC controller. This enables real-time acquisition, analysis, and early warning of operating parameters, ensuring safe and stable system operation.

[0020] With a reasonable overall structure and high degree of automation, it effectively solves the problems of highly corrosive wastewater, high fluoride content, and difficult treatment in the hydrogen fluoride production process, realizes efficient recycling of water resources, reduces operating costs and environmental risks, and has good economic benefits and environmental value. Attached Figure Description

[0021] Figure 1 This is a front view schematic diagram of the overall equipment of this utility model;

[0022] Figure 2 This is a top view of the overall structure of the device according to this utility model;

[0023] Figure 3 This is a schematic diagram of the cross-sectional structure of the sedimentation tank of this utility model;

[0024] Figure 4 This is a schematic cross-sectional view of the pH adjustment box of this utility model;

[0025] Figure 5 This is a schematic cross-sectional view of the multi-media filter box of this utility model;

[0026] Figure 6 This is a schematic diagram of the arrangement of the quartz sand layer and activated carbon layer within the filter screen frame of this utility model;

[0027] Figure 7 This is a schematic diagram of the connection architecture between the PLC controller and its components in this utility model;

[0028] In the diagram: 1. Grit chamber; 2. pH adjustment tank; 3. Multi-media filter box; 4. Reclaimed water tank; 5. Bar screen; 6. Fluoroplastic pipe; 7. Fluorine-lined centrifugal pump; 8. Feed hopper; 9. Flow valve; 10. Agitator motor; 11. Liquid inlet; 12. Water pump; 13. Outlet pipe; 14. Outlet valve; 15. Sewage pipe; 16. Sewage valve; 17. Filter screen frame; 18. Flow sensor; 19. Corrosion rate sensor; 20. Fluoride ion concentration detector; 21. Drain pipe; 22. Drain valve; 23. pH sensor; 24. Agitator; 25. Electrochemical defluorination unit; 26. Inclined sand discharge plate; 27. Quartz sand layer; 28. Activated carbon layer; 29. ​​Liquid level sensor; 30. Water quality sensor. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] Please see Figure 1-7 The water circulation equipment for hydrogen fluoride production process of this utility model includes:

[0031] The graded pretreatment module includes a grit chamber 1 and a pH adjustment tank 2. The grit chamber 1 is equipped with a grid 5 on the top and an inclined sand discharge plate 26 on the bottom. The grit chamber 1 is connected to the pH adjustment tank 2, and the pH adjustment tank 2 is equipped with a liquid inlet 11.

[0032] The intelligent purification and reuse module includes a multi-media filter box 3, an electrochemical defluorination unit 25, and a reuse water tank 4. The multi-media filter box 3 is filled with a quartz sand layer 27 and an activated carbon layer. The electrochemical defluorination unit 25 is installed at the bottom of the multi-media filter box 3. The multi-media filter box 3 is connected to the reuse water tank 4 through a pipe. The reuse water tank 4 is equipped with a drain pipe 21 and an electric valve. The pH adjustment tank 2 is connected to the multi-media filter box 3 through a water outlet pipe 13. The water outlet pipe 13 is equipped with a water pump 12 and a water outlet valve 14. The bottom of the multi-media filter box 3 is equipped with a sewage pipe 15 and a sewage valve 16.

[0033] This technical solution removes solid impurities from hydrogen fluoride production wastewater and adjusts the pH value through a staged pretreatment module, preventing impurity blockage and corrosion from acidic wastewater. The corrosion-resistant transmission module uses fluoride-resistant materials and corrosion inhibitors to achieve low-loss wastewater transmission. The intelligent purification and reuse module reduces fluoride ion concentration through multi-media filtration and electrochemical defluorination to meet recycling standards. The end-to-end monitoring module collects data such as flow rate, corrosion rate, and fluoride ion concentration in real time, enabling automated control and anomaly warnings via a PLC controller. These modules work together to address the pain points of traditional equipment, such as severe corrosion, incomplete purification, and low reuse rates, improving water recycling efficiency and reducing equipment corrosion rates.

[0034] The graded pretreatment module is a crucial pre-treatment step in the water circulation process. Through three stages of coordinated action—screen 5 filtration, grit separation, and pH adjustment—it provides qualified water for subsequent purification and transmission. The specific principle is as follows:

[0035] The top side frame of the grit chamber 1 supports the grid 5. Hydrogen fluoride wastewater, such as tail gas washing wastewater, first flows through the grid 5 to intercept solid impurities such as silicon slag and fluoride crystals in the water, so as to avoid impurities scratching the subsequent fluoroplastic pipes 6 or clogging the fluoropolymer-lined centrifugal pump 7.

[0036] After filtration, the wastewater enters the grit chamber 1. The inclined grit discharge plate 26 at the bottom of the chamber uses gravity to accelerate the sedimentation of grit, such as fine quartz sand and fluoride. The grit slides down the inclined surface to the grit collection area at the bottom of the chamber. The grit is cleaned manually or mechanically regularly to prevent the long-term accumulation of grit from reducing the volume of the chamber.

[0037] The filter screen frame 17 on the top side frame of the multi-media filter box 3 carries the quartz sand layer 27 and the activated carbon layer. The filter screen frame 17 can prevent the filter media from being lost with the water flow and facilitate the replacement of the filter media.

[0038] The stirring motor 10 inside the pH adjustment tank 2 drives the stirring paddle 24 to rotate, so that the wastewater and alkaline solution, such as 30% sodium hydroxide solution, are fully mixed.

[0039] pH sensor 23 monitors the pH value of water in real time. When pH < 6.5 is detected, acidic wastewater is prone to aggravating fluoride corrosion. The PLC controller triggers the alkaline solution dosing device to adjust the pH to the neutral range of 6.5-7.5, reducing the corrosion pressure on the subsequent anti-corrosion transmission module. Under neutral conditions, the permeability of fluoride ions to fluoroplastic pipe 6 can be reduced to below 0.01 mg / (m²·d), which is 50% less than that under acidic conditions.

[0040] The corrosion-resistant transmission module is designed specifically for the highly corrosive nature of hydrogen fluoride wastewater. Through a dual mechanism of corrosion-resistant materials and corrosion inhibitor protection, it achieves safe and efficient wastewater transmission. The specific principle is as follows:

[0041] Fluoroplastic pipe 6 is made of PVDF material, with a polytetrafluoroethylene coating sprayed on the inner wall. The CF bond energy of polytetrafluoroethylene is extremely high, and fluoride ions have difficulty destroying its molecular structure, which can effectively block the contact corrosion between fluoride ions and the pipe, extending the service life of the pipe to more than 5 years.

[0042] The impeller and pump casing of the fluoropolymer-lined centrifugal pump 7 are made of fluoropolymer alloy. This material is not only resistant to fluorine corrosion, but also has high wear resistance, which can prevent residual impurities in wastewater from causing wear on the pump body and extend its life by more than 3 times compared with traditional stainless steel centrifugal pumps.

[0043] The corrosion inhibitor dosing hopper 8 stores a special corrosion inhibitor for fluoride ions, such as benzotriazole as the main component, with a concentration of 5-10 mg / L. The bottom flow valve 9 accurately adds the inhibitor according to the instructions of the PLC controller.

[0044] After the corrosion inhibitor enters the fluoroplastic pipe 6 with the wastewater, it will form a dense adsorption film on the inner wall of the pipe and the pump body. This film can competitively adsorb fluoride ions and prevent fluoride ions from reacting chemically with the material surface, such as preventing the formation of fluorides on metal materials.

[0045] When the corrosion rate sensor 19 detects that the corrosion rate on the outer wall of the fluoropolymer-lined centrifugal pump 7 is ≥0.1 mm / a, the PLC controller automatically increases the opening of the flow valve 9 to raise the concentration of the corrosion inhibitor to 12-15 mg / L, dynamically enhancing the protective effect and ensuring that the corrosion rate is controlled below 0.05 mm / a.

[0046] The intelligent purification and reuse module is the core purification unit of the water cycle. It achieves deep water purification through multi-media filtration and electrochemical defluorination, and ensures safe reuse by combining liquid level and water quality monitoring. The specific principle is as follows:

[0047] The quartz sand layer 27 inside the multi-media filter box 3 uses mechanical interception and adsorption to remove suspended solids in the wastewater, such as fine silica slag and colloidal particles, reducing the turbidity from 10-20 scattered turbidity units to below 5 scattered turbidity units.

[0048] The upper activated carbon layer removes organic matter from wastewater, such as byproducts of hydrogen fluoride production and some fluoride ions, through pore adsorption, thus reducing the load on subsequent electrochemical defluorination.

[0049] The electrochemical defluorination unit 25 uses a titanium-based lead dioxide electrode (anode) and a stainless steel electrode (cathode) with a distance of 5-10 cm between the two electrodes. A DC voltage of 5-10V is applied. An oxidation reaction occurs at the anode: 2H2O-4e⁻=O2↑+4H⁺. The generated H⁺ combines with fluoride ions in the wastewater to form HF.

[0050] Simultaneously, a reduction reaction occurs at the cathode: 2H₂O + 2e⁻ = H₂↑ + 2OH⁻. OH⁻ combines with calcium ions in the water to form Ca(OH)₂, which then reacts with HF to form insoluble CaF₂ precipitate. Ksp = 3.4 × 10⁻¹¹;

[0051] The precipitate is discharged through the drain port at the bottom of the multi-media filter box 3, and the fluoride ion concentration can be reduced from 20-50 mg / L to below 1 mg / L, meeting the reuse standards for hydrogen fluoride production tail gas washing and equipment cooling.

[0052] The liquid level sensor 29 in the recycled water tank 4 monitors the water volume in real time. When the liquid level is below 10%, the PLC controller adjusts the outlet valve 14 to increase the outlet flow of the multi-media filter box 3. When the liquid level is above 90%, the outlet valve 14 is closed to prevent overflow.

[0053] The water quality sensor 30 monitors the fluoride ion concentration in the recycled water in real time. If the concentration is ≤1mg / L, the PLC controller opens the electric valve on the drain pipe 21 to discharge the recycled water to the next application equipment, such as the exhaust gas scrubbing tower or equipment cooling system, as needed. If the concentration is >1mg / L, the electric valve is closed and an alarm is triggered to ensure safe reuse.

[0054] The end-to-end monitoring module is the intelligent hub of the equipment. It collects data through multi-dimensional sensors and uses a PLC controller to achieve closed-loop control. The specific principle is as follows:

[0055] The flow sensor 18 is installed at the inlet of the fluoroplastic pipe 6 to monitor the wastewater flow rate. If the flow rate is lower than the preset value, such as 5 m³ / h, it is determined that the pipe is blocked or the pump is faulty, and the PLC controller triggers an alarm.

[0056] The corrosion rate sensor 19 is attached to the outer wall of the fluoropolymer-lined centrifugal pump 7. It uses a resistance probe to measure the corrosion rate of the pump body in real time. The data is transmitted to the PLC controller and compared with a preset threshold, such as 0.1 mm / a. If the threshold is exceeded, the amount of corrosion inhibitor added is increased.

[0057] Fluoride ion concentration detector 20 is installed at the top of fluoroplastic pipe 6 and the outlet end of water pipe 13 to monitor the fluoride concentration of influent, judge the pretreatment effect, ensure compliance, and immediately disconnect the reuse link when the data is abnormal.

[0058] Closed-loop control logic of PLC controller

[0059] The PLC controller receives signals from various sensors and automatically controls the actions of each module according to a preset program: for example, starting the addition of alkali solution when the pH value is too low, triggering pump body inspection when the flow rate is abnormal, and closing the reuse valve when the fluoride ion exceeds the standard.

[0060] Meanwhile, the PLC controller can be connected to a remote monitoring platform to upload operating parameters in real time, such as flow rate, pH value, corrosion rate, and fluoride ion concentration. It supports historical data query with a storage period of ≥1 year and abnormal alarms, such as SMS / email notifications, to achieve unmanned operation and maintenance.

[0061] Detailed Workflow

[0062] Phase 1: Equipment Pre-processing and Parameter Setting

[0063] Inspection of the pretreatment module: the screen of the 5-grit filter is undamaged, the grit chamber 1 is free of sand accumulation, and the alkaline solution level in the pH adjustment tank 2 is ≥50%.

[0064] Inspection of the corrosion-resistant transmission module: No leaks were found in the fluoroplastic pipe 6, the oil level in the fluoropolymer-lined centrifugal pump 7 was normal, and the corrosion inhibitor in the corrosion inhibitor dosing hopper 8 was sufficient.

[0065] Inspection of the intelligent purification and reuse module: The quartz sand and activated carbon layers in the multi-media filter box 3 are flat, the electrodes of the electrochemical defluorination unit 25 are free of oxidation, and the reuse water tank 4 is clean and free of impurities.

[0066] The core parameters are set through the PLC controller: pH adjustment target 6.5-7.5, corrosion inhibitor dosage concentration 5-10 mg / L, and fluoride ion recycling threshold ≤1 mg / L;

[0067] Calibrate the sensors: Ensure the accuracy of data from the pH sensor 23, fluoride ion concentration detector 20, and corrosion rate sensor 19.

[0068] Stage 2: Hierarchical Preprocessing

[0069] Wastewater from hydrogen fluoride production, such as tail gas scrubbing wastewater, with a flow rate of 10-20 m³ / h, is fed into grit chamber 1. It first passes through top grid 5 to intercept solid impurities such as silicon slag and fluoride crystals.

[0070] After filtration, the wastewater enters the grit chamber 1. The grit is deposited to the bottom of the chamber by the inclined grit discharge plate 26. When the grit layer reaches a thickness of 20cm, an ultrasonic level sensor 29 is usually installed on the grit chamber 1 to monitor it and carry out manual or mechanical sand removal.

[0071] After sedimentation, the wastewater flows into the pH adjustment tank 2 through the pipe. The stirring motor 10 drives the stirring paddle 24 to rotate, so that the wastewater is evenly mixed.

[0072] pH sensor 23 monitors water quality in real time. If pH < 6.5, 30% sodium hydroxide solution is added to pH adjustment tank 2 through liquid inlet 11 until pH stabilizes at 7.0 ± 0.5. After adjustment, the wastewater is transported to intelligent purification and reuse module through anti-corrosion transmission module.

[0073] Phase 3: Corrosion-resistant transmission

[0074] The PLC controller starts the fluoropolymer-lined centrifugal pump 7, and the pretreated wastewater is transported to the multi-media filter box 3 through the fluoroplastic pipeline 6. The flow sensor 18 monitors the transmission flow in real time to ensure that it is stable at 10-20 m³ / h. If the flow fluctuates by ±20%, the pump body pressure check is triggered.

[0075] The corrosion inhibitor is added at a concentration of 5-10 mg / L through the bottom flow valve 9 of the corrosion inhibitor dosing hopper 8. The corrosion inhibitor is fully mixed with the wastewater in the pipeline, forming an adsorption film on the inner wall of the pipeline and the pump body.

[0076] The corrosion rate sensor 19 monitors the corrosion rate of the outer wall of the fluoropolymer-lined centrifugal pump 7 in real time. If the rate is ≥0.1mm / a, the PLC controller automatically increases the opening of the flow valve 9 to increase the concentration of the corrosion inhibitor to 12-15mg / L, and sends an early warning message on the remote platform.

[0077] Phase 4: Intelligent Purification

[0078] Wastewater is pumped from pH adjustment tank 2 by water pump 12 and enters multi-media filter tank 3 through water outlet pipe 13. The water flow of the water discharged from water outlet pipe 13 can be adjusted by water outlet valve 14. First, it flows through the upper activated carbon layer to adsorb organic matter and some fluoride ions, and then flows through the lower quartz sand layer 27 to remove suspended solids. After treatment, the turbidity of the wastewater is reduced to below 5 scattered turbidity units, and the fluoride ion concentration is initially reduced to 15-30 mg / L.

[0079] Fluoride ion concentration detector 20 is installed at the top of fluoroplastic pipe 6 and at the outlet of water outlet pipe 13 to monitor the fluoride concentration of influent in real time. If the concentration is >50mg / L, the pretreatment effect is judged to be poor, and the PLC controller reduces the influent flow rate and extends the filtration time.

[0080] After filtration, the wastewater enters the electrochemical defluorination unit 25 at the bottom of the multi-media filter box 3. The PLC controller starts the titanium-based lead dioxide electrode and applies an 8V DC voltage.

[0081] An electrochemical reaction occurs at the electrode, where fluoride ions combine with calcium ions to form CaF2 precipitate. The precipitate is periodically discharged through the drain valve 16 on the drain pipe 15. After treatment, the fluoride ion concentration in the wastewater drops to below 1 mg / L and is discharged into the recycled water tank 4 through a pipeline.

[0082] Phase 5: Reuse and Monitoring

[0083] The liquid level sensor 29 in the recycled water tank 4 monitors the water volume and maintains the liquid level at 30%-80%; the water quality sensor 30 detects the fluoride ion concentration in the recycled water. If it is ≤1mg / L, the PLC controller opens the electric valve on the drain pipe 21 and distributes the recycled water according to the set ratio: 65% is sent to the tail gas scrubbing tower, 25% is sent to the equipment cooling system, and 10% is reserved for backup.

[0084] If the fluoride ion concentration is >1 mg / L, immediately close the electric valve and direct the wastewater to the emergency treatment module, such as an activated carbon adsorption tower, and reuse it after it meets the standards.

[0085] The PLC controller continuously receives data such as flow rate, corrosion rate, pH value, and fluoride ion concentration, and displays them synchronously on the local touch screen and the remote platform.

[0086] If any abnormality occurs, such as pipe blockage, accelerated pump corrosion, or excessive fluoride ions, an audible and visual alarm will be triggered immediately, and a text message / email will be sent to the maintenance personnel via a remote platform. The maintenance personnel can remotely view the abnormal data and guide the on-site troubleshooting.

[0087] Phase 6: Equipment Maintenance and Cleaning

[0088] Routine maintenance

[0089] Daily: Clean impurities from the grid 5, check corrosion inhibitor and alkali solution levels, and calibrate pH sensor 23;

[0090] Weekly: Backwash the multi-media filter box 3, rinse the filter media with recycled clean water, backwash time 10-15 minutes, and check the sealing of the fluoropolymer-lined centrifugal pump 7;

[0091] Monthly: Replace electrode 25 of the electrochemical defluorination unit, replenish quartz sand and activated carbon, and calibrate fluoride ion concentration detector 20.

[0092] Regularly clean the sedimentation tank to ensure sufficient tank volume.

[0093] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A water circulation system for hydrogen fluoride production, characterized in that, include: The graded pretreatment module includes a grit chamber (1) and a pH adjustment tank (2). The grit chamber (1) is equipped with a grid (5) on the top and an inclined sand discharge plate (26) on the bottom. The grit chamber (1) is connected to the pH adjustment tank (2), and the pH adjustment tank (2) is equipped with a liquid inlet (11). The intelligent purification and reuse module includes a multi-media filter box (3), an electrochemical defluorination unit (25), and a reuse water tank (4). The multi-media filter box (3) is filled with a quartz sand layer (27) and an activated carbon layer. The electrochemical defluorination unit (25) is installed at the bottom of the multi-media filter box (3). The multi-media filter box (3) is connected to the reuse water tank (4) through a pipe. The reuse water tank (4) is equipped with a drain pipe (21) and an electric valve. The pH adjustment tank (2) is connected to the multi-media filter box (3) through an outlet pipe (13). The outlet pipe (13) is equipped with a water pump (12) and an outlet valve (14). The bottom of the multi-media filter box (3) is equipped with a sewage pipe (15) and a sewage valve (16) is installed on the sewage pipe (15).

2. The water circulation equipment for hydrogen fluoride production process according to claim 1, characterized in that, It also includes a corrosion-resistant transmission module, which includes a fluoroplastic pipe (6), a fluoropolymer-lined centrifugal pump (7), and a corrosion inhibitor dosing hopper (8). The inner wall of the fluoroplastic pipe (6) is coated with polytetrafluoroethylene. The fluoropolymer-lined centrifugal pump (7) is connected in series with the fluoroplastic pipe (6). The bottom of the dosing hopper (8) is equipped with a flow valve (9). The two ends of the fluoroplastic pipe (6) are respectively connected to the sedimentation tank (1) and the pH adjustment box (2).

3. The water circulation equipment for hydrogen fluoride production process according to claim 2, characterized in that, The pH adjustment tank (2) is equipped with a stirring paddle (24) and a pH sensor (23). A stirring motor (10) is installed on the top of the pH adjustment tank (2). The output end of the stirring motor (10) passes through the pH adjustment tank (2) and is connected to the stirring paddle (24).

4. The water circulation equipment for hydrogen fluoride production process according to claim 3, characterized in that, The electrochemical defluorination unit (25) uses a titanium-based lead dioxide electrode, the recycled water tank (4) is equipped with a liquid level sensor (29), and the drain pipe (21) is equipped with a water quality sensor (30).

5. The water circulation equipment for hydrogen fluoride production process according to claim 4, characterized in that, It also includes a full-link monitoring module, which is electrically connected to the graded pretreatment module, the anti-corrosion transmission module, and the intelligent purification and reuse module, respectively. The full-link monitoring module includes a flow sensor (18), a corrosion rate sensor (19), a fluoride ion concentration detector (20), and a PLC controller.

6. The water circulation equipment for hydrogen fluoride production process according to claim 5, characterized in that, The flow sensor (18) is installed at the inlet of the fluoroplastic pipe (6), the corrosion rate sensor (19) is attached to the outer wall of the fluoropolymer-lined centrifugal pump (7), and the fluoride ion concentration detector (20) is installed at the top of the fluoroplastic pipe (6) and the outlet of the water outlet pipe (13). The PLC controller is electrically connected to the liquid level sensor (29), water quality sensor (30), flow sensor (18), corrosion rate sensor (19), fluoride ion concentration detector (20), fluoropolymer-lined centrifugal pump (7), water pump (12), water outlet valve (14), sewage valve (16), stirring motor (10), electric valve and pH sensor (23).

7. The water circulation equipment for hydrogen fluoride production process according to claim 1, characterized in that, The top of the sedimentation tank (1) and the multi-media filter box (3) is provided with a side frame. The side of the grid (5) is placed on the side frame of the sedimentation tank (1). The side frame of the multi-media filter box (3) is provided with a filter screen frame (17). The quartz sand layer (27) and the activated carbon layer are laid in the filter screen frame (17).

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