A fully automatic cleaning process for an ultrafiltration device

Abstract

The present invention discloses a fully automatic cleaning process for an ultrafiltration device, which relates to the technical field of water treatment in thermal power plants and includes an ultrafiltration device. The device system adopts a fully automatic cleaning process, with small operation volume and high reliability. It can greatly reduce the total amount of various wastewaters, achieve a relatively high recovery rate, effectively reduce the water consumption of the whole plant. At the same time, it greatly reduces the corrosion of the flushing device on the pipeline system. Through the detection module, multi-dimensional data such as the inlet and production water pressure, flow rate, water quality, operation time, and cleaning times are monitored in real time, and the degree of membrane fouling is comprehensively calculated to ensure that cleaning is started before the membrane fouling affects the system performance, avoid the aggravation of pollution, and ensure the efficient operation of the ultrafiltration system. By regularly calculating the numerical value of the membrane fouling degree, the growth trend of membrane fouling can be tracked in real time, early intervention can be carried out, the cleaning timing can be optimized, excessive accumulation of membrane fouling can be prevented, the impact on the system operation can be reduced, the operation cost can be lowered, and frequent shutdowns and increased cleaning difficulty caused by serious membrane fouling can be avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment in thermal power plants, and particularly to a fully automatic cleaning process for ultrafiltration devices. Background Art

[0002] With the rapid development of China's economy, the demand for electricity continues to grow. As one of the main power generation methods, the scale of thermal power generation is constantly expanding. However, a large amount of wastewater is generated during the thermal power generation process. If not properly treated, it will cause serious environmental pollution. Therefore, it is of great significance to develop efficient, economical, and environmentally friendly water treatment technologies for thermal power plants.

[0003] In the water treatment process of thermal power plants, the ultrafiltration system plays a crucial role. It effectively removes impurities such as suspended solids, colloids, and bacteria in water through the principle of physical screening, provides high-quality influent for the subsequent desalination process, and ensures the safe and stable operation of the boiler system. However, during the long-term operation of the ultrafiltration membrane, it will inevitably be contaminated, resulting in a decrease in membrane flux and an increase in operating pressure, ultimately affecting the system efficiency and service life.

[0004] Therefore, developing efficient and environmentally friendly ultrafiltration system cleaning technologies is of great significance for maintaining the stable operation of the ultrafiltration system, reducing operating costs, extending the membrane service life, and solving pipeline corrosion, etc. Summary of the Invention

[0005] The present invention provides a fully automatic cleaning process for ultrafiltration devices to solve the problems in the background art.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A fully automatic cleaning process for ultrafiltration devices, comprising an ultrafiltration device, a disc filter, an ultrafiltration water tank, an ultrafiltration cleaning device, a reverse osmosis flushing water pump, an ultrafiltration device cleaning liquid inlet valve, a reverse osmosis flushing water pump, a reverse osmosis water tank, and a dosing device;

[0008] The inlet end of the ultrafiltration device is connected to the outlet end of the disc filter, and the outlet end is connected to the inlet end of the ultrafiltration water tank;

[0009] The inlet end of the ultrafiltration cleaning device is connected to the outlet of the reverse osmosis flushing water pump, and the outlet end is connected to the ultrafiltration device cleaning liquid inlet valve;

[0010] The inlet end of the reverse osmosis flushing water pump is connected to the reverse osmosis water tank, and the outlet end is connected to the ultrafiltration cleaning device;

[0011] The chemical dosing device includes a sodium hypochlorite metering tank, a sodium hypochlorite metering pump, a liquid caustic soda metering tank, a liquid caustic soda metering pump, a hydrochloric acid metering tank, and a hydrochloric acid metering pump. The inlet end of the sodium hypochlorite metering pump is connected to the sodium hypochlorite metering tank, and the outlet end is connected to the ultrafiltration cleaning device; the inlet end of the liquid caustic soda metering pump is connected to the liquid caustic soda metering tank, and the outlet end is connected to the ultrafiltration cleaning device; the inlet end of the hydrochloric acid metering pump is connected to the hydrochloric acid metering tank, and the outlet end is connected to the ultrafiltration cleaning device;

[0012] During the cleaning process of the ultrafiltration device, the detection module inside the controller detects the data of the inlet and outlet water pressure, flow rate, water quality, operation time, and cleaning times of the ultrafiltration device. Then, the analysis module inside the controller analyzes the detected data to determine the degree of membrane fouling, the membrane fouling growth rate, and the remaining service life of the membrane. Subsequently, corresponding execution signals are generated, enabling the execution module inside the controller to perform corresponding operations after receiving the corresponding execution signals.

[0013] Preferably, the ultrafiltration device includes a cleaning liquid inlet valve, an air inlet valve, an upper backwash discharge valve, a lower backwash discharge valve, a cleaning concentrated water return valve, a cleaning product water return valve, a backwash inlet valve, and a product water valve.

[0014] Preferably, the ultrafiltration cleaning device further includes an ultrafiltration cleaning water tank, an ultrafiltration cleaning water pump I, an ultrafiltration cleaning water pump II, a security filter, a pneumatic valve for the security filter outlet header pipe, a pneumatic isolation valve for reverse osmosis flushing water to the ultrafiltration cleaning water tank, and a pneumatic valve for the ultrafiltration cleaning water tank recirculation pipeline.

[0015] Preferably, the ultrafiltration cleaning device can operate fully automatically and program-controlled during the enhanced backwash A (CEB-A) cleaning, enhanced backwash B (CEB-B) cleaning, and restorative cleaning (CIP) of the ultrafiltration system.

[0016] Preferably, a detection module, an analysis module, and an execution module are provided inside the controller of the ultrafiltration device;

[0017] The detection module detects the data of the inlet and outlet water pressure, flow rate, water quality, operation time, and cleaning times of the ultrafiltration device, and transmits the detected data to the analysis module;

[0018] An analysis module analyzes and processes the data transmitted by the detection module, calculates the degree of influence of the detection data on membrane fouling, determines whether the membrane fouling has reached a preset membrane fouling degree threshold. If it reaches, a pollution cleaning signal is generated and transmitted to the execution module; detects the growth rate of membrane fouling, determines whether the membrane fouling will reach a preset ratio threshold after growth. If it reaches, a warning signal is generated and transmitted to the execution module; retrieves and analyzes the historical detection data of the detection module during the operation of the ultrafiltration device, predicts the remaining service life of the membrane, determines whether the remaining service life has reached a preset remaining service life threshold. If it reaches, a membrane replacement signal is generated and transmitted to the execution module;

[0019] An execution module receives the signals transmitted by the analysis module and then performs corresponding operations.

[0020] Preferably, the analysis steps for the analysis module to analyze the degree of influence of the detection data on membrane fouling are as follows:

[0021] S1: The inlet pressure is , the permeate pressure is , the pressure difference , the influence coefficient of the preset pressure difference on the membrane fouling degree is , then the degree of influence of the water pressure factor on the membrane fouling degree ;

[0022] S2: The inlet flow rate is , the permeate flow rate is , the flow ratio , the influence coefficient of the preset flow rate on the membrane fouling degree is , the degree of influence of the flow rate factor on the membrane fouling degree ;

[0023] S3: The comprehensive water quality index , is the turbidity, is the fouling index, is the organic matter content, the influence coefficient of the preset water quality on the membrane fouling degree is , then the degree of influence of the water quality factor on the membrane fouling degree ;

[0024] S4: The operation time is , the influence coefficient of the preset operation time on the membrane fouling degree is , then the degree of influence of the operation time factor on the membrane fouling degree ;

[0025] S5: The number of cleaning times is , the time since the last cleaning is , the cleaning effect coefficient is , the preset comprehensive influence coefficient of cleaning on the degree of membrane fouling is , then the influence degree of the cleaning factor on the degree of membrane fouling ;

[0026] S6: Considering all the above influencing factors, the degree of membrane fouling , compare the obtained degree of membrane fouling with the preset membrane fouling degree threshold . If , generate a pollution cleaning signal and transmit the pollution cleaning signal to the execution module; otherwise, calculate the difference between the degree of membrane fouling and the preset membrane fouling degree threshold , .

[0027] Preferably, the analysis steps for the growth of membrane fouling by the analysis module are as follows:

[0028] K1: At regular intervals of a set time period, calculate the values of the degree of membrane fouling to obtain values of the degree of membrane fouling. Sort the values of the degree of membrane fouling obtained according to the acquisition time sequence, establish a coordinate system of the acquisition time and the values of the degree of membrane fouling, plot coordinate points in the coordinate system and connect them, then calculate the slope of the connection line, and mark the connection lines with a slope greater than zero;

[0029] K2: Taking the current time point as the base point, if there is a connection line with a slope greater than zero within the set time period before the base point, calculate the growth value of the degree of membrane fouling corresponding to the slope of the connection line. If , it is determined that the membrane fouling has a tendency to reach the cleaning condition, and a secondary judgment of the trend is carried out, is the value of the degree of membrane fouling detected currently;

[0030] K3: Calculate the mean value of the values of the degree of membrane fouling and the standard deviation . Establish the fluctuation range of the calculated data with the obtained mean value and the standard deviation . Mark the values of the degree of membrane fouling that are not within the fluctuation range among the values of the degree of membrane fouling as outliers, count the number a of outliers. If the preset proportion threshold , it is determined that the fluctuation of the calculated values of the degree of membrane fouling is large, generate a warning signal, and transmit the warning signal to the execution module.

[0031] Preferably, the analysis module performs the following steps for analyzing the remaining service life of the membrane:

[0032] M1: Establish a combined feature vector based on the data obtained above , and establish a model for the remaining service life of the membrane with a linear regression model of the model, is the intercept, is the coefficient of each feature, is each feature in the feature vector, is the error term;

[0033] M2: Use historical data to train the model, and substitute the obtained historical data into the mean squared error loss function , is the number of samples, is the actual remaining service life of the membrane, is the remaining service life of the membrane predicted by the model; obtain the model parameters corresponding to the historical data through the training of the historical data ;

[0034] M3: Root mean square error , mean absolute error , compare the calculated value and value with the preset thresholds of the corresponding items respectively. If both are respectively less than the preset thresholds of the corresponding items, it is determined that the model prediction effect is good; otherwise, re-select historical data for model training operations;

[0035] M4: During the operation of the ultrafiltration device, calculate the current calculated feature vector through the real-time detected data and the trained model, and input the current feature vector into the trained model to predict the remaining service life of the membrane in the current situation; when the remaining service life of the membrane is less than the preset remaining service life threshold, generate a membrane replacement signal and transmit the membrane replacement signal to the execution module.

[0036] Preferably, the execution module performs the following steps for operation execution:

[0037] N1: After receiving the pollution cleaning signal, perform the cleaning operation of the membrane;

[0038] N2: After the execution module receives the warning signal, transmit the differential pressure data between the inlet water and the product water of the ultrafiltration device to the analysis module. The analysis module compares the differential pressure data with the preset differential pressure threshold, and performs the comparison between the growth value of the membrane pollution degree and . If one of the two comparisons is greater than the preset threshold of the corresponding item , it is determined that the membrane fouling is about to reach the cleaning condition, a pre-cleaning signal is generated, and the pre-cleaning signal is transmitted to the execution module;

[0039] N3: After receiving the pre-cleaning signal, perform the cleaning operation of the membrane.

[0040] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows:

[0041] 1. The present invention adopts a fully automatic cleaning process, reducing the amount of manual operation; it has high reliability, can operate fully automatically, operates safely and stably, reduces labor intensity, improves cleaning efficiency, and ultimately reduces the operation and maintenance costs of the ultrafiltration system;

[0042] 2. The present invention can clean efficiently, restore the ultrafiltration membrane flux, and extend the service life of the ultrafiltration membrane;

[0043] 3. The present invention greatly reduces the total amount of various wastewaters, can achieve a high recovery rate, effectively reduces the water consumption of the whole plant, reduces the total amount of wastewaters of the whole plant, and has profound significance for doing a good job in water conservation in thermal power plants;

[0044] 4. The present invention greatly reduces the corrosion of the flushing device to the pipeline system;

[0045] 5. The present invention monitors the multi-dimensional data such as the inlet and production water pressure, flow rate, water quality, operation time, and cleaning times in real time through the detection module, comprehensively calculates the degree of membrane fouling, ensures that cleaning is started before the membrane fouling affects the system performance, avoids the aggravation of fouling, effectively restores the membrane flux, ensures the efficient operation of the ultrafiltration system, and extends the membrane service life; by regularly calculating the numerical value of the membrane fouling degree, drawing the curve of its change with time and calculating the slope, it can track the growth trend of membrane fouling in real time, intervene in advance, optimize the cleaning timing, prevent excessive accumulation of membrane fouling, reduce the impact on system operation, reduce operation costs, and avoid frequent shutdowns and increased cleaning difficulty caused by severe membrane fouling; using the obtained multi-factor data to construct a combined feature vector to predict the remaining service life of the membrane, enabling the operator to know in advance the service life status of the membrane, reasonably arrange the membrane replacement plan, prepare spare membrane modules in advance, reduce the system downtime caused by sudden membrane failure, ensure the continuous and stable operation of the water treatment system in thermal power plants, and at the same time avoid resource waste caused by premature replacement and reduce maintenance costs.

[0046] In summary: The fully automatic cleaning process of an ultrafiltration device in this patent application has the advantages of high efficiency, mildness, environmental protection, economy, etc., can effectively solve the problems existing in the prior art, and provides a guarantee for the safe and stable operation of the water treatment system in thermal power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Attached Figure 1 is a structural schematic diagram of a fully automatic cleaning process of an ultrafiltration device.

[0048] Appendix Figure 2 The following is the system flow chart of the present invention:

[0049] Legend Explanation:

[0050] 1. Cleaning liquid inlet valve; 2. Air inlet valve; 3. Upper backwash drain valve; 4. Lower backwash drain valve; 5. Cleaning concentrated water return valve; 6. Cleaning product water return valve; 7. Backwash inlet valve; 8. Product water valve; 9. Pneumatic isolation valve for reverse osmosis flush water to ultrafiltration cleaning water tank; 10. Pneumatic valve for recirculation pipeline of ultrafiltration cleaning water tank; 11. Pneumatic valve for outlet header pipe of security filter. Specific Embodiments

[0051] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0052] Please refer to Figure 1 - Figure 2 , the present invention provides a technical solution: a fully automatic cleaning process for an ultrafiltration device, including an ultrafiltration device, a disc filter, an ultrafiltration water tank, an ultrafiltration cleaning device, a reverse osmosis flush water pump, an ultrafiltration device cleaning liquid inlet valve, a reverse osmosis flush water pump, a reverse osmosis water tank, and a chemical dosing device;

[0053] The inlet end of the ultrafiltration device is connected to the outlet end of the disc filter, and the outlet end is connected to the inlet end of the ultrafiltration water tank; and the system start-up water production and backwashing of the ultrafiltration device can both be fully automatic program-controlled operations, improving the automation of the ultrafiltration device;

[0054] The inlet end of the ultrafiltration cleaning device is connected to the outlet of the reverse osmosis flush water pump, and the outlet end is connected to the ultrafiltration device cleaning liquid inlet valve;

[0055] The inlet end of the reverse osmosis flush water pump is connected to the reverse osmosis water tank, and the outlet end is connected to the ultrafiltration cleaning device;

[0056] The chemical dosing device includes a sodium hypochlorite metering tank, a sodium hypochlorite metering pump, a liquid caustic soda metering tank, a liquid caustic soda metering pump, a hydrochloric acid metering tank, and a hydrochloric acid metering pump. The inlet end of the sodium hypochlorite metering pump is connected to the sodium hypochlorite metering tank, and the outlet end is connected to the ultrafiltration cleaning device; the inlet end of the liquid caustic soda metering pump is connected to the liquid caustic soda metering tank, and the outlet end is connected to the ultrafiltration cleaning device. The inlet end of the hydrochloric acid metering pump is connected to the hydrochloric acid metering tank, and the outlet end is connected to the ultrafiltration cleaning device; among them, the start and stop of the metering pump, the preparation of the liquid medicine, and the circulation of the solution tank in the chemical dosing device can all be fully automatic program-controlled operations, improving the automation of the chemical dosing device and facilitating the accurate and rapid addition of medicines to the water.

[0057] In the present invention, the ultrafiltration device includes a cleaning liquid inlet valve 1, an air inlet valve 2, an upper backwash drain valve 3, a lower backwash drain valve 4, a cleaning concentrated water return valve 5, a cleaning product water return valve 6, a backwash inlet valve 7, and a product water valve 8.

[0058] In the present invention, the ultrafiltration cleaning device further includes an ultrafiltration cleaning water tank, an ultrafiltration cleaning water pump I, an ultrafiltration cleaning water pump II, a security filter, a pneumatic valve 11 at the outlet header of the security filter, a pneumatic isolation valve 9 for reverse osmosis flushing water to the ultrafiltration cleaning water tank, and a pneumatic valve 10 for the recirculation pipeline of the ultrafiltration cleaning water tank.

[0059] In the present invention, the ultrafiltration cleaning device can operate fully automatically and programmatically during enhanced backwash A (CEB-A) cleaning, enhanced backwash B (CEB-B) cleaning, and restorative cleaning (CIP) of the ultrafiltration system.

[0060] Among them, the fully automatic cleaning process system of the ultrafiltration device can operate fully automatically. After clicking the "startup" button, it enters the "ultrafiltration startup sequence control" interface. When starting, the ultrafiltration system can automatically enter the operation according to the set program. Automatically open the ultrafiltration product water pneumatic valve and the ultrafiltration inlet pneumatic valve, open the outlet electric valve of the selected clean water pump, start the clean water pump, and run for 3600 seconds (can be set); when the ultrafiltration system runs for 3600 seconds, it automatically enters the backwash.

[0061] After the backwash is started, it automatically enters the air wash; stop the clean water pump, close the outlet electric valve of the clean water pump, the ultrafiltration inlet pneumatic valve, and the ultrafiltration product water pneumatic valve, open the ultrafiltration upper backwash drain pneumatic valve and the ultrafiltration air inlet pneumatic valve, and perform the air wash for 30 seconds; perform the air wash and backwash; open the ultrafiltration backwash inlet pneumatic valve, put into use the ultrafiltration backwash water pump, and perform the air-backwash for 30 seconds; empty: close the ultrafiltration air inlet pneumatic valve, stop the ultrafiltration backwash water pump, close the ultrafiltration backwash inlet pneumatic valve, open the ultrafiltration lower backwash drain pneumatic valve, and perform the emptying for 40 seconds; forward wash: close the ultrafiltration lower backwash drain pneumatic valve, open the ultrafiltration inlet pneumatic valve and the outlet electric valve of the clean water pump, put into operation the clean water pump, and perform the forward wash for 60 seconds; return to operation: open the ultrafiltration product water pneumatic valve, close the ultrafiltration upper backwash drain pneumatic valve, open the ultrafiltration inlet pneumatic valve, and the ultrafiltration device continues to be put into operation and continues to produce water.

[0062] When the normal backwashing times reach 47 times, it automatically enters enhanced backwashing A (CEB-A). CEB-A has two cleaning modes: "sodium hypochlorite" or "sodium hypochlorite + alkali". The program automatically stops the clean water pump, closes the ultrafiltration inlet valve, and closes the ultrafiltration product water valve; opens the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank, starts the reverse osmosis flushing water pump. When the liquid level in the ultrafiltration cleaning water tank reaches 0.9 m (can be set), stops the reverse osmosis flushing water pump, and closes the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank after 15 seconds. Opens the solenoid valve for adding sodium hypochlorite to the ultrafiltration, starts the sodium hypochlorite metering pump, and stops it after 20 seconds (can be set). The concentration of the prepared sodium hypochlorite solution is about 250 ppm. If the "sodium hypochlorite + alkali" cleaning mode is selected, opens the solenoid valve for adding alkali to the ultrafiltrate, starts the liquid alkali metering pump, and controls the pH of the added medicine solution to be 11 - 12. Opens the pneumatic valve for recirculation in the ultrafiltration cleaning water tank, starts the preselected ultrafiltration cleaning water pump, with a frequency of 42 Hz (can be set), and stops the ultrafiltration cleaning water pump after circulating for 5 minutes (can be set), then closes the pneumatic valve for recirculation in the ultrafiltration cleaning water tank. Opens the pneumatic valve for lower discharge of ultrafiltration backwashing and the pneumatic valve for upper discharge of ultrafiltration backwashing, and closes the pneumatic valve for lower discharge of ultrafiltration backwashing and the pneumatic valve for upper discharge of ultrafiltration backwashing after draining for 60 seconds (can be set). Opens the pneumatic valve for ultrafiltration cleaning product water, the pneumatic valve for ultrafiltration cleaning concentrated water outlet, the pneumatic valve for ultrafiltration cleaning device product water, and the pneumatic valve for ultrafiltration cleaning inlet. Starts the preselected ultrafiltration cleaning water pump, with a frequency of 42 Hz (can be set), and stops the ultrafiltration cleaning water pump after circulating for 15 minutes (can be set). Closes the pneumatic valve for ultrafiltration cleaning device product water, the pneumatic valve for ultrafiltration cleaning inlet, the pneumatic valve for ultrafiltration cleaning product water, and the pneumatic valve for ultrafiltration cleaning concentrated water outlet. Opens the pneumatic valve for bottom exhaust in the ultrafiltration cleaning water tank, and drains the remaining liquid medicine in the ultrafiltration cleaning water tank (the timing is set to 360 seconds). When the cleaning water tank is emptied, closes the pneumatic valve for bottom exhaust in the ultrafiltration cleaning water tank, and opens the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank. Starts the reverse osmosis flushing water pump, and stops the reverse osmosis flushing water pump when the liquid level reaches 0.9 m (can be set), and closes the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank after 15 seconds. Opens the pneumatic valve for ultrafiltration cleaning product water, the pneumatic valve for ultrafiltration cleaning concentrated water outlet, the pneumatic valve for ultrafiltration cleaning device product water, and the pneumatic valve for ultrafiltration cleaning inlet. Starts the preselected ultrafiltration cleaning water pump, with a frequency of 42 Hz (can be set), and stops the ultrafiltration cleaning water pump after circulating for 5 minutes (can be set). Closes the pneumatic valve for ultrafiltration cleaning device product water, the pneumatic valve for ultrafiltration cleaning inlet, the pneumatic valve for ultrafiltration cleaning product water, and the pneumatic valve for ultrafiltration cleaning concentrated water outlet. Opens the pneumatic valve for bottom exhaust in the ultrafiltration cleaning water tank, drains the remaining liquid medicine in the ultrafiltration cleaning water tank, and closes the pneumatic valve for bottom exhaust in the ultrafiltration cleaning water tank after the timing is set to 380 seconds (can be set). Opens the pneumatic valve for upper discharge of ultrafiltration backwashing, opens the ultrafiltration inlet valve (the opening degree is set to 60%, can be set), starts the clean water pump at the normal washing frequency, and after running for 3 minutes, the system resumes water production.

[0063] When the enhanced backwash A (CEB-A) reaches 6 times, it automatically enters the enhanced backwash B (CEB-B). The programmable controller automatically stops the clean water pump, closes the ultrafiltration inlet valve, and closes the ultrafiltration product water valve. Open the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank, start the reverse osmosis flushing water pump. When the liquid level in the ultrafiltration cleaning water tank reaches 0.9 m (can be set), stop the reverse osmosis flushing water pump. After 15 seconds, close the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank, and open the pneumatic valve for recirculation in the ultrafiltration cleaning water tank. Open the solenoid valve for adding hydrochloric acid to the ultrafiltration, and stop it after starting the hydrochloric acid metering pump for 20 seconds (can be set). Control the pH of the dosing solution to be 2.0 - 2.5. Start the preselected ultrafiltration cleaning water pump, with a frequency of 42 Hz (can be set). After circulating for 5 minutes (can be set), stop the ultrafiltration cleaning water pump, and close the pneumatic valve for recirculation in the ultrafiltration cleaning water tank. Open the pneumatic valve for lower discharge of ultrafiltration backwash and the pneumatic valve for upper discharge of ultrafiltration backwash. After draining for 60 seconds (can be set), close the pneumatic valve for lower discharge of ultrafiltration backwash and the pneumatic valve for upper discharge of ultrafiltration backwash. Open the pneumatic valve for ultrafiltration cleaning product water, the pneumatic valve for ultrafiltration cleaning concentrated water outlet, the pneumatic valve for ultrafiltration cleaning device product water, and the pneumatic valve for ultrafiltration cleaning inlet. Start the preselected ultrafiltration cleaning water pump, with a frequency of 42 Hz (can be set). After circulating for 15 minutes (can be set), stop the ultrafiltration cleaning water pump. Close the pneumatic valve for ultrafiltration cleaning device product water, the pneumatic valve for ultrafiltration cleaning inlet, the pneumatic valve for ultrafiltration cleaning product water, and the pneumatic valve for ultrafiltration cleaning concentrated water outlet. Open the pneumatic valve for bottom exhaust of the ultrafiltration cleaning water tank to empty the remaining liquid medicine in the ultrafiltration cleaning water tank (the timing is set to 380 seconds, can be set). When the cleaning water tank is emptied, close the pneumatic valve for bottom exhaust of the ultrafiltration cleaning water tank, and open the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank. Start the reverse osmosis flushing water pump. When the liquid level reaches 0.9 m (can be set), stop the reverse osmosis flushing water pump. After 15 seconds, close the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank. Open the pneumatic valve for ultrafiltration cleaning product water, the pneumatic valve for ultrafiltration cleaning concentrated water outlet, the pneumatic valve for ultrafiltration cleaning device product water, and the pneumatic valve for ultrafiltration cleaning inlet. Start the preselected ultrafiltration cleaning water pump, with a frequency of 42 Hz (can be set). After circulating for 5 minutes (can be set), stop the ultrafiltration cleaning water pump. Close the pneumatic valve for ultrafiltration cleaning device product water, the pneumatic valve for ultrafiltration cleaning inlet, the pneumatic valve for ultrafiltration cleaning product water, and the pneumatic valve for ultrafiltration cleaning concentrated water outlet. Open the pneumatic valve for bottom exhaust of the ultrafiltration cleaning water tank to empty the remaining liquid medicine in the ultrafiltration cleaning water tank (the timing is set to 380 seconds, can be set), and then close the pneumatic valve for bottom exhaust of the ultrafiltration cleaning water tank. Open the pneumatic valve for upper discharge of ultrafiltration backwash, open the ultrafiltration inlet valve (the opening degree is set to 60%, can be set), start the clean water pump at the normal washing frequency, and after running for 3 minutes, the system starts to make water again.

[0064] When the differential pressure between the influent and effluent of the ultrafiltration device reaches 0.08 MPa, chemical cleaning of the ultrafiltration device is required. After clicking the "CIP" button, enter the "CIP sequence control" interface and click start to automatically enter the restorative cleaning according to the set program. After the restorative cleaning program control is started, enter the replacement: there are two cleaning modes, "sodium hypochlorite chemical cleaning" or "acid chemical cleaning". The program control automatically stops the clean water pump, closes the ultrafiltration influent valve, and closes the ultrafiltration effluent valve. Open the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank, start the reverse osmosis flushing water pump, and stop the reverse osmosis flushing water pump when the liquid level in the ultrafiltration cleaning water tank reaches 0.9 m (can be set). After 15 seconds, close the pneumatic valve for replenishing water in the ultrafiltration cleaning water tank. If the "sodium hypochlorite chemical cleaning" mode is selected, open the solenoid valve for adding sodium hypochlorite to the ultrafiltration, start the sodium hypochlorite metering pump, and stop it after 40 seconds (can be set). The concentration of the prepared sodium hypochlorite solution is about 500 ppm; open the solenoid valve for adding alkali to the ultrafiltrate, start the caustic soda metering pump, and control the pH of the added medicine solution to be 11-12. If the "acid chemical cleaning" mode is selected, open the solenoid valve for adding hydrochloric acid to the ultrafiltration, start the hydrochloric acid metering pump, and control the pH of the added medicine solution to be 2.0-2.5. Open the pneumatic valve for recirculation in the ultrafiltration cleaning water tank, start the preselected ultrafiltration cleaning water pump, with a frequency of 42 Hz (can be set), and stop the ultrafiltration cleaning water pump after circulating for 5 minutes (can be set). Close the pneumatic valve for recirculation in the ultrafiltration cleaning water tank. Open the pneumatic valve for upper discharge during ultrafiltration backwashing, open the pneumatic valve for cleaning inlet of the ultrafiltration, start the ultrafiltration cleaning water pump, and perform replacement for 40 seconds; Circulation: Open the pneumatic valve for cleaning effluent of the ultrafiltration, open the pneumatic valve for cleaning concentrate of the ultrafiltration, close the pneumatic valve for upper discharge during ultrafiltration backwashing, and circulate for 10 minutes; Soaking: Stop the ultrafiltration cleaning water pump, close the pneumatic valve for cleaning inlet of the ultrafiltration, close the pneumatic valve for cleaning effluent of the ultrafiltration, close the pneumatic valve for cleaning concentrate of the ultrafiltration, and soak for 5 hours; Circulation: Open the pneumatic valve for cleaning concentrate of the ultrafiltration, open the pneumatic valve for cleaning effluent of the ultrafiltration, open the pneumatic valve for cleaning inlet of the ultrafiltration, start the ultrafiltration cleaning water pump, and circulate for 5 minutes; Air washing: Stop the ultrafiltration cleaning water pump, close the pneumatic valve for cleaning inlet of the ultrafiltration, close the pneumatic valve for cleaning concentrate of the ultrafiltration, close the pneumatic valve for cleaning effluent of the ultrafiltration, open the pneumatic valve for upper discharge during ultrafiltration backwashing, open the pneumatic valve for air inlet of the ultrafiltration, and air wash for 30 seconds; Air wash + backwash: Open the pneumatic valve for backwashing inlet of the ultrafiltration, start the ultrafiltration backwashing water pump, and continue for 30 seconds; Rinsing: Close the pneumatic valve for air inlet of the ultrafiltration, open the pneumatic valve for lower discharge during ultrafiltration backwashing, and continue for 1 minute. Emptying: Stop the ultrafiltration backwashing water pump, close the pneumatic valve for backwashing inlet of the ultrafiltration, and continue for 40 seconds; Normal washing: Close the pneumatic valve for lower discharge during ultrafiltration backwashing, open the pneumatic valve for inlet of the ultrafiltration, open the electric valve at the outlet of the selected cleaning water pump, start the clean water pump, and continue for 3 minutes; Stop the clean water pump, close the electric valve at the outlet of the selected cleaning water pump, close the pneumatic valve for inlet of the ultrafiltration, and close the pneumatic valve for upper discharge during ultrafiltration backwashing.

[0065] For the backwashing of the ultrafiltration system, enhanced backwashing A (CEB-A), enhanced backwashing B (CEB-B), and restorative cleaning (CIP), set program control logic locks, and only one of the four ultrafiltration units can be operated.

[0066] For the ultrafiltration system device, when "Circulation Input" in the backwashing sequence control is activated, it can achieve automatic cyclic water production of a single set of ultrafiltration through program control. When "Circulation Cut-off" in the backwashing sequence control is activated, it can achieve automatic shutdown of a single set of ultrafiltration through program control. When "Sorting Input" is activated on the ultrafiltration system interface, it can achieve cyclic single-set cleaning of four sets of ultrafiltration with automatic sorting. When "Re-sorting" is activated, it can achieve program-controlled circulation of other sets of ultrafiltration. When "Sorting Cut-off" is activated, it can achieve manual cyclic operation of four sets of ultrafiltration through program control.

[0067] Inside the controller of the ultrafiltration device, there are a detection module, an analysis module, and an execution module;

[0068] The inlet water pressure is , the product water pressure is , the pressure difference , the influence coefficient of the preset pressure difference on the membrane fouling degree is , then the influence degree of the water pressure factor on the membrane fouling degree ;

[0069] The inlet water flow rate is , the product water flow rate is , the flow rate ratio , the influence coefficient of the preset flow rate on the membrane fouling degree is , the influence degree of the flow rate factor on the membrane fouling degree ;

[0070] The turbidity , value, the organic matter content affect the quality of the water. The comprehensive water quality index , the influence coefficient of the preset water quality on the membrane fouling degree is , then the influence degree of the water quality factor on the membrane fouling degree ;

[0071] The operation time is , the influence coefficient of the preset operation time on the membrane fouling degree is , then the influence degree of the operation time factor on the membrane fouling degree ;

[0072] The number of cleaning times is , the time since the last cleaning is , the cleaning effect coefficient is , The value range of is, 1 indicates excellent cleaning effect and the membrane fouling is basically restored; 0 indicates no cleaning effect. The comprehensive influence coefficient of the preset cleaning on the membrane fouling degree is , then the influence degree of the cleaning factor on the membrane fouling degree ;

[0073] Considering the above various influencing factors, the degree of membrane fouling , the obtained degree of membrane fouling is compared with the preset threshold of membrane fouling degree . If , a pollution cleaning signal is generated and transmitted to the execution module; otherwise, the difference between the degree of membrane fouling and the preset threshold of membrane fouling degree is calculated .

[0074] According to the data obtained above, a combined feature vector is established, and a model for the remaining service life of the membrane is established with a linear regression model , where is the coefficient of each feature is each feature in the feature vector is the error term; the model is trained using historical data, and the obtained historical data is substituted into the mean square error loss function , where is the actual remaining service life of the membrane is the predicted remaining service life of the membrane by the model; the model parameters corresponding to the historical data are obtained through the training of historical data; the performance of the model is evaluated, the root mean square error , the mean absolute error , and the calculated value and value are respectively compared with the preset thresholds of the corresponding items. If both are respectively less than the preset thresholds of the corresponding items, it is determined that the model prediction effect is good; otherwise, historical data is reselected for model training operation;

[0075] During the operation of the ultrafiltration device, the current calculated feature vector is calculated through the real-time detected data and the trained model, and the current feature vector is input into the trained model to predict the remaining service life of the membrane under the current situation; when the remaining service life of the membrane is less than the preset remaining service life threshold, a membrane replacement signal is generated and transmitted to the execution module.

[0076] At regular intervals of a set time period, the value of the membrane fouling degree is calculated to obtain membrane fouling degree values, and the calculated The membrane fouling degree values are sorted in the order of collection time, a coordinate system of collection time and membrane fouling degree values is established, coordinate points are plotted in the coordinate system and connected by lines, then the slope of the connected line is calculated, and the lines with a slope greater than zero are marked; taking the current time point as the base point, if there is a line with a slope greater than zero within the set time period before the base point, then calculate the growth value of the membrane fouling degree corresponding to the slope of the line for calculation, if , it is determined that the membrane fouling has a tendency to reach the cleaning condition, and a secondary judgment of the trend is carried out is the membrane fouling degree value detected currently;

[0077] Calculate the mean value of the membrane fouling degree values and the standard deviation , and establish the fluctuation range of the calculated data with the obtained mean value and the standard deviation. Mark the values outside the fluctuation range among the membrane fouling degree values as outliers, count the number a of outliers. If the preset proportion threshold , it is determined that the fluctuation of the calculated membrane fouling degree values is large, a warning signal is generated, and the warning signal is transmitted to the execution module; After the execution module receives the pollution cleaning signal, it performs the cleaning operation of the membrane; after the execution module receives the warning signal, it transmits the differential pressure data between the inlet water and the produced water of the ultrafiltration device to the analysis module. The analysis module compares the differential pressure data with the preset differential pressure threshold, and compares the growth value of the membrane fouling degree

[0078] with and . If one of the two comparisons is greater than the preset threshold of the corresponding item , it is determined that the membrane fouling is about to reach the cleaning condition, a pre-cleaning signal is generated, and the pre-cleaning signal is transmitted to the execution module.

[0079] Working principle: Connect tap water to this system, and add chemicals for enhanced cleaning, namely sodium hypochlorite, liquid caustic soda, and hydrochloric acid. The ultrafiltration system operates automatically for water production, which can effectively remove particles, colloids, bacteria, heat sources, and organic matters in water. The ultrafiltration system performs automatic backwashing, which can effectively remove pollutants and blockages on the membrane surface, restore the membrane flux, improve the filtration efficiency, reduce membrane fouling and scaling, lower the risk of membrane damage, and extend its service life. The ultrafiltration system performs automatic chemical addition and enhanced cleaning. Through the dissolution, oxidation, or dispersion of chemical agents, it can effectively remove pollutants such as organic matters, colloids, and microorganisms that are difficult to remove by ordinary backwashing, can more thoroughly remove the pollution layer on the membrane surface, and significantly restore the membrane flux and improve the filtration efficiency of the system.

[0080] The ultrafiltration system features fully automatic backwashing, combined with a fully automatic chemical dosing and enhanced washing process system. Through the synergistic effect of chemical agents, it can more thoroughly remove contaminants on the surface of the ultrafiltration membrane, significantly restore membrane flux, extend membrane life, improve water production quality, and reduce operating costs. Reasonable use of chemical dosing and enhanced washing can effectively handle complex water quality and high pollution loads, maintaining the efficient and stable operation of the ultrafiltration system. It can restore membrane performance more quickly, extend the time of efficient system operation, reduce system downtime, improve operating efficiency, and enhance water production quality.

[0081] After tap water passes through the disc filter, it is filtered by the ultrafiltration system to produce water and enters the ultrafiltration water tank. The start-up sequence control enables the ultrafiltration system to automatically enter operation according to the set program. When it has run for 3600 seconds (which can be set), it automatically enters backwashing. The backwashing sequence control allows the ultrafiltration system to automatically enter operation according to the set program and fully automate the backwashing process. When the normal backwashing frequency reaches 47 times, it automatically enters enhanced backwashing A (CEB-A) and fully executes the enhanced backwashing A process. When enhanced backwashing A (CEB-A) reaches 6 times, it automatically enters enhanced backwashing B (CEB-B) and fully executes the enhanced backwashing B process. When the pressure difference between the inlet and outlet water of the ultrafiltration device reaches 0.08 MPa, it can enter the restoration cleaning of the ultrafiltration system and fully execute the restoration cleaning (CIP) process. The start and stop of all equipment and the opening and closing of valves are fully automated by the DCS system program, effectively realizing water production, backwashing, chemical dosing and enhanced washing, and restoration cleaning of the ultrafiltration system.

[0082] The above description of the embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fully automatic cleaning process for an ultrafiltration device, characterized in that: It includes an ultrafiltration device, a laminated filter, an ultrafiltration water tank, an ultrafiltration cleaning device, a reverse osmosis flushing water pump, a cleaning liquid inlet valve, a reverse osmosis water tank and a dosing device; The inlet end of the ultrafiltration device is connected to the outlet end of the laminated filter, and the outlet end is connected to the inlet end of the ultrafiltration water tank; The inlet end of the ultrafiltration cleaning device is connected to the outlet of the reverse osmosis flushing water pump, and the outlet end is connected to the cleaning liquid inlet valve; The inlet end of the reverse osmosis flushing water pump is connected to the reverse osmosis water tank, and the outlet end is connected to the ultrafiltration cleaning device; The dosing device comprises a sodium hypochlorite metering box, a sodium hypochlorite metering pump, a liquid alkali metering box, a liquid alkali metering pump, a hydrochloric acid metering box, and a hydrochloric acid metering pump. The inlet end of the sodium hypochlorite metering pump is connected to the sodium hypochlorite metering box, and the outlet end is connected to the ultrafiltration cleaning device; the inlet end of the liquid alkali metering pump is connected to the liquid alkali metering box, and the outlet end is connected to the ultrafiltration cleaning device; the inlet end of the hydrochloric acid metering pump is connected to the hydrochloric acid metering box, and the outlet end is connected to the ultrafiltration cleaning device; During the cleaning process of the ultrafiltration device, the inlet and outlet water pressure, flow rate, water quality, operating time and cleaning times of the ultrafiltration device are detected by the detection module inside the controller, and then the detected data are analyzed by the analysis module inside the controller to determine the degree of membrane contamination, membrane contamination growth and remaining service life of the membrane, and then the corresponding execution signal is generated, so that the execution module inside the controller executes the corresponding operation after receiving the corresponding execution signal; The analysis module analyzes the degree of membrane contamination using test data in the following steps: S1: water inlet pressure is , the water production pressure is , pressure difference , the influence coefficient of the preset pressure difference on the membrane fouling degree is , then the influence of water pressure factors on the degree of membrane fouling ; S2: water inlet flow rate is , the water flow rate is , flow ratio , the influence coefficient of preset flow rate on membrane fouling degree is , the influence of flow factors on the degree of membrane fouling ; S3: Comprehensive water quality indicators , is turbidity, is the pollution index, is the organic matter content, and the influence coefficient of water quality on membrane fouling degree is preset as , then the influence of water quality factors on the degree of membrane fouling ; S4: running time is , the influence coefficient of preset operation time on membrane fouling degree is , then the influence of the operating time factor on the degree of membrane fouling ; S5: The number of cleaning times is , the time since the last cleaning is , the cleaning effect coefficient is , the comprehensive influence coefficient of preset cleaning on membrane fouling degree is , then the influence of cleaning factors on the degree of membrane fouling ; S6: Based on the above factors, the degree of membrane fouling , the membrane fouling degree With the preset membrane fouling threshold For comparison, if , a pollution cleaning signal is generated and transmitted to the execution module; otherwise, the degree of membrane pollution is calculated. Preset membrane fouling threshold The difference , ; The analysis module performs the following steps to analyze membrane fouling growth: K1: The degree of membrane pollution is measured at a set time interval. Calculate the value of The membrane fouling degree value is calculated The membrane pollution degree values ​​are sorted in the order of collection time, and a coordinate system of collection time and membrane pollution degree values ​​is established. The coordinate points are drawn in the coordinate system, and lines are connected. Then, the slope of the connecting line is calculated, and the connecting line with a slope greater than zero is marked. K2: Taking the current time point as the base point, if there is a line with a slope greater than zero within the set time period forward from the base point, the membrane pollution degree growth value corresponding to the slope of the line Calculate if , it is determined that the membrane pollution has a tendency to reach the cleaning condition, and a secondary judgment of the trend is performed; K3: Calculation The average value of membrane fouling degree and standard deviation , to calculate the mean and standard deviation Establish the fluctuation range of calculated data ,right The membrane pollution degree values ​​that are not within the fluctuation range are marked as outliers, and the number of outliers a is counted. If the preset ratio threshold , it is determined that the calculated membrane contamination degree value fluctuates greatly, a warning signal is generated, and the warning signal is transmitted to the execution module.

2. The fully automatic cleaning process of an ultrafiltration device according to claim 1, characterized in that: The ultrafiltration device comprises an air inlet valve (2), a backwash upper discharge valve (3), a backwash lower discharge valve (4), a cleaning concentrated water return valve (5), a cleaning produced water return valve (6), a backwash water inlet valve (7), and a produced water valve (8).

3. The fully automatic cleaning process of an ultrafiltration device according to claim 2, characterized in that: The ultrafiltration cleaning device also includes an ultrafiltration cleaning water tank, an ultrafiltration cleaning water pump 1, an ultrafiltration cleaning water pump 2, a safety filter, a safety filter outlet main pipe pneumatic valve (11), a reverse osmosis flushing water to ultrafiltration cleaning water tank pneumatic isolation valve (9), and an ultrafiltration cleaning water tank recirculation pipeline pneumatic valve (10).

4. The fully automatic cleaning process of an ultrafiltration device according to claim 3, characterized in that: The ultrafiltration cleaning device can be fully automatically programmed to operate during enhanced backwash A (CEB-A), enhanced backwash B (CEB-B) and restorative cleaning (CIP) of the ultrafiltration system.

5. The fully automatic cleaning process of an ultrafiltration device according to claim 1, characterized in that: The controller of the ultrafiltration device is internally provided with a detection module, an analysis module and an execution module; A detection module detects the inlet and outlet water pressure, flow rate, water quality, operating time and cleaning times of the ultrafiltration device, and transmits the detected data to the analysis module; The analysis module analyzes and processes the data transmitted by the detection module, calculates the influence of the detection data on the membrane pollution, determines whether the membrane pollution reaches the preset membrane pollution degree threshold, generates a pollution cleaning signal if it reaches it, and transmits the pollution cleaning signal to the execution module; detects the growth of membrane pollution, determines whether the membrane pollution will reach the preset ratio threshold after growth, generates a warning signal if it reaches it, and transmits the warning signal to the execution module; retrieves and analyzes various detection history data of the detection module during the operation of the ultrafiltration device, predicts the remaining service life of the membrane, determines whether the remaining service life reaches the preset remaining service life threshold, generates a membrane replacement signal if it reaches it, and transmits the membrane replacement signal to the execution module; The execution module receives the signal transmitted by the analysis module and then performs the corresponding operation.

6. The fully automatic cleaning process of an ultrafiltration device according to claim 1, characterized in that: The analysis module analyzes the remaining service life of the membrane in the following steps: M1: Create a combined feature vector based on the data obtained above , the remaining service life of the membrane is established by linear regression model Model, is the intercept, is the coefficient of each feature, are the features in the feature vector, is the error term; M2: Use historical data to train the model and substitute the acquired historical data into the mean square error loss function , is the sample size, is the actual remaining membrane service life, The remaining service life of the membrane predicted by the model; the model parameters corresponding to the historical data are obtained through training with historical data ; M3: Root mean square error , mean absolute error , the calculated Value and The values ​​are compared with the preset thresholds of the corresponding items. If both are smaller than the preset thresholds of the corresponding items, the prediction effect of the model is judged to be good. Otherwise, historical data is re-selected for model training; M4: During the operation of the ultrafiltration device, the current calculation feature vector is calculated using the real-time detected data and the trained model , and the current feature vector The input is into the trained model to predict the remaining service life of the membrane under the current circumstances; when the remaining service life of the membrane is less than the preset remaining service life threshold, a membrane replacement signal is generated and passed to the execution module.

7. The fully automatic cleaning process of an ultrafiltration device according to claim 6, characterized in that: The steps for executing the module to perform operations are as follows: N1: After receiving the pollution cleaning signal, perform the membrane cleaning operation; N2: After receiving the warning signal, the execution module transmits the pressure difference data between the inlet and product water of the ultrafiltration device to the analysis module. The analysis module compares the pressure difference data with the preset pressure difference threshold and calculates the membrane pollution degree growth value. and If there is a comparison between the two comparisons that is greater than the preset threshold of the corresponding item , it is determined that the membrane pollution is about to reach the cleaning condition, a pre-cleaning signal is generated, and the pre-cleaning signal is transmitted to the execution module; N3: After receiving the pre-cleaning signal, perform the membrane cleaning operation.

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