High-efficiency automatic control method and system for submerged ultrafiltration membrane

Abstract

The application discloses a kind of high-efficiency automatic control method and system of submerged ultrafiltration membrane, including ultrafiltration water production control program, chemical cleaning control program;Ultrafiltration water production control program controls the water of ultrafiltration membrane pool to pass through ultrafiltration membrane and carries out water outlet;When opening water production pump and carrying out water production, water passes through ultrafiltration membrane and carries out water outlet from its inside;When carrying out chemical cleaning, according to the kind of cleaning reagent and cleaning mode, there will be different implementation procedures, and chemical cleaning can remove inorganic and organic matter attached to ultrafiltration membrane, so that ultrafiltration membrane restores optimal water permeability.The water quality and quantity obtained by the control method are stable, the service life of ultrafiltration membrane is long, the system recovery rate is high, the operation cost is low, and the degree of automation is high.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of water treatment, and particularly relates to a submerged ultrafiltration membrane whole-process automatic control method and system. BACKGROUND

[0002] Ultrafiltration is a membrane separation technology capable of purifying and separating a solution, and an ultrafiltration membrane is an artificial filter membrane used in an ultrafiltration process. The ultrafiltration membrane is generally made of high polymer materials such as PVDF, PP and PS. The ultrafiltration membrane is a solution separation device with an ultrafiltration membrane wire as a filter medium and a pressure difference between two sides of the membrane as a driving force. The ultrafiltration membrane only allows solvents (such as water molecules), inorganic salts and soluble organic matters in the solution to pass through, and retains suspended matters, colloids and microorganisms in the solution, so as to achieve the purpose of purification and separation. At present, the ultrafiltration membrane is widely used in water treatment processes, and the ultrafiltration technology plays an increasingly important role in the fields of reverse osmosis pretreatment, drinking water treatment and reclaimed water reuse.

[0003] In recent years, the ultrafiltration membrane process has gradually been recognized and respected in the industry. The whole system includes ultrafiltration water production, physical cleaning, chemical cleaning, chemical liquid preparation, chemical liquid neutralization, waste liquid discharge and other blocks. The ultrafiltration water production often has a higher requirement for the system recovery rate (equal to the net water production / total water production). High recovery rate indicates high system operation efficiency and low operation cost. Due to the continuous expansion of the ultrafiltration scale, the improvement of the requirements of the staff on the operation conditions and the pursuit of high efficiency of the ultrafiltration treatment, how to realize the efficient, stable and automatic operation of the ultrafiltration system has become a problem to be solved. However, the achievements in this aspect in China are still very few. SUMMARY

[0004] To solve the above problems, the application provides an efficient automatic control method and system capable of improving the operation safety and treatment efficiency of the submerged ultrafiltration membrane system and saving operation cost.

[0005] To achieve the above target, the application adopts the following technical solutions:

[0006] An efficient automatic control method of a submerged ultrafiltration membrane, comprising:

[0007] The control program of the water production of the ultrafiltration membrane tank: the water of the ultrafiltration membrane tank flows into the inlet channel, and the inlet channel is provided with a thermometer, a liquid level meter and a turbidity meter for detecting the water quality and quantity of the inlet water. The water production flow of the membrane tank can be set according to the measured temperature value, liquid level value and turbidity value of the inlet water. When the temperature value is lower than 15℃, the water production flow of the membrane tank is lowered to 80% of the designed flow; when the temperature value is higher than 15℃, the water production flow is the designed flow; when the liquid level value is higher than 2m, the water production flow of the membrane tank is increased; when the liquid level value is lower than 2m, the water production flow is decreased; when the turbidity value is higher than 5NTU, the water production flow is decreased; and when the turbidity value is lower than 5NTU, the water production flow is increased. The inlet flow of the ultrafiltration membrane tank is adjusted by controlling the opening degree of the gate valve through the PLC, and the inside of the ultrafiltration membrane tank is provided with a static pressure liquid level meter. Whether the water production pump is started and whether the inlet gate valve is opened are determined according to the measured value of the static pressure liquid level meter. When the liquid level of the membrane tank is lower than L liquid level, the inlet gate valve is opened; when the liquid level of the membrane tank is higher than H liquid level, the inlet gate valve is closed; when the liquid level of the membrane tank is higher than L liquid level, the vacuum jet is started and stopped after about 10-30s, then the water production valve is opened, and then the water production pump is started, and the system starts to produce water; when the liquid level of the membrane tank is lower than LL liquid level, the water production pump is stopped, the water production valve is closed, and the water production program is ended. When the system is normally operated, the water production time is set according to a fixed cycle, generally 20-50 minutes, and the water production is stopped when the set cycle is reached. The LL liquid level is a protection liquid level for preventing the damage of the ultrafiltration membrane due to dryness and preventing the damage of the water production pump due to empty pumping. The L liquid level is a starting liquid level of the water production of the ultrafiltration, and the H liquid level is a stopping liquid level of the inlet water to prevent overflow caused by excessive inlet water of the membrane tank.

[0008] The control program of the chemical cleaning: the outlet pipeline of the ultrafiltration membrane tank is provided with a pressure gauge, and the transmembrane pressure difference of the ultrafiltration membrane can be calculated according to the measured value of the pressure gauge and the measured value of the static pressure liquid level meter. The value reflects the water permeability of the ultrafiltration membrane, and whether the ultrafiltration membrane needs to be cleaned can be determined. When the system is normally operated, the frequency of the maintenance cleaning and the recovery cleaning is set according to a fixed water production cycle. The transmembrane pressure difference is used as a reference value and a protection value for the cleaning of the ultrafiltration membrane. When the transmembrane pressure difference is 0-30KPa, the water permeability of the ultrafiltration membrane is good; when the transmembrane pressure difference is 30-60KPa, the maintenance cleaning is needed; when the transmembrane pressure difference is 60-80KPa, the recovery cleaning is needed; and when the transmembrane pressure difference is 80KPa or above, the protection value is reached, that is, when the set value is reached, the PLC control system sends an alarm signal and stops the water production. When the chemical cleaning is performed, different implementation programs can be used according to the types and cleaning methods of the cleaning agents. The chemical cleaning can remove the inorganic and organic matters attached to the ultrafiltration membrane, so that the water permeability of the ultrafiltration membrane is restored to the best.

[0009] Acid soak washing: open the acid cleaning inlet valve, open the acid cleaning outlet valve, and then open the acid cleaning water pump. When the membrane pool liquid reaches the LL level, stop adding the chemical, close the acid cleaning water pump, and then close the acid cleaning inlet valve. Open the acid cleaning outlet valve. After the acid soak reaches the set time, if the number of repeated use of the chemical has not reached the set number, open the chemical backflow valve, and then open the acid liquid backflow valve and the acid cleaning inlet valve. The chemical backflows into the acid cleaning pool. After the chemical backflow is completed, close the chemical backflow valve, the acid liquid backflow valve, and the acid cleaning inlet valve. The acid soak program is completed, and the membrane pool rinsing and pipeline flushing program is entered. If the number of repeated use of the chemical reaches the set number, open the waste liquid discharge valve. The chemical is discharged into the neutralization pool. After the discharge is completed, close the waste liquid discharge valve. The acid soak program is completed, and the membrane pool rinsing and pipeline flushing program is entered.

[0010] or base soak washing: open the base cleaning inlet valve, open the base cleaning outlet valve, and then open the base cleaning water pump. When the membrane pool liquid reaches the LL level, stop adding the chemical, close the base cleaning water pump, and then close the base cleaning inlet valve and the base cleaning outlet valve. After the base soak reaches the set time, if the number of repeated use of the chemical has not reached the set number, open the chemical backflow valve, and then open the base liquid backflow valve and the base cleaning inlet valve. The chemical backflows into the base cleaning pool. After the chemical backflow is completed, close the chemical backflow valve, the base liquid backflow valve, and the base cleaning inlet valve. The base soak program is completed, and the membrane pool rinsing and pipeline flushing program is entered. If the number of repeated use of the chemical reaches the set number, open the waste liquid discharge valve. The chemical is discharged into the neutralization pool. After the discharge is completed, close the waste liquid discharge valve. The base soak program is completed, and the membrane pool rinsing and pipeline flushing program is entered.

[0011] Membrane pool rinsing and pipeline flushing: open the water gate valve. When the membrane pool liquid level reaches the LL level, close the water gate valve, open the cleaning circulation valve, open the base cleaning outlet valve and the base cleaning water pump when the cleaning is base washing, and open the acid cleaning outlet valve and the acid cleaning water pump when the cleaning is acid washing. The water in the membrane pool circulates between the membrane pool, the water production pipeline, the chemical backflow pipe, and the chemical inlet pipe. The membrane pool is rinsed and the pipeline is flushed. The time is about 2-10 minutes. Then close the corresponding cleaning water pump, close the cleaning circulation valve and the corresponding cleaning outlet valve, and open the waste liquid discharge valve. The rinsing liquid is discharged into the neutralization pool. After the membrane pool is emptied, close the waste liquid discharge valve. This is one membrane pool rinsing and pipeline flushing process. Then repeat the program once. After the membrane pool rinsing and pipeline flushing is completed, open the water gate valve. When the membrane pool liquid level reaches the L level, the membrane pool enters the normal water production state.

[0012] The membrane pool rinsing and pipeline flushing program is an auxiliary program of the chemical cleaning control program. It mainly reduces the residual concentration of chemical cleaning agents in the membrane pool and cleans the water production pipeline, the chemical inlet pipeline, and the chemical backflow pipe to ensure the water quality.

[0013] Further, it also includes physical cleaning control program: the ultrafiltration membrane is physically cleaned once every certain time of water production, namely backwashing and air washing are simultaneously performed, firstly, the liquid level of the ultrafiltration membrane tank is lowered for filtration, the inlet sluice valve is closed, the membrane tank continues to produce water, when the liquid level of the membrane tank is lower than the LL liquid level, the water production pump is closed, the water production valve is closed, then the backwashing valve is opened, the backwashing pump is opened, the air washing valve is opened, the Roots blower is opened, 50-70s later, the backwashing pump and the Roots blower are closed, the backwashing valve and the air washing valve are closed, the physical cleaning is completed, the inlet sluice valve is opened, and the system enters the water production state again. After the physical cleaning reaches the set number of times, generally 3-6 times, the waste water discharge valve is opened, the backwashing waste water in the ultrafiltration membrane tank is discharged into the waste water discharge tank, when the membrane tank is emptied, the waste water discharge valve is closed, the inlet sluice valve is opened, and the system enters the water production program again.

[0014] When the backwashing waste water emptying of the physical cleaning control program is completed, the waste water discharge valve is closed, and the chemical cleaning control program is started.

[0015] The larger suspended matters, colloids and the like are intercepted outside the ultrafiltration membrane, when the impurities outside the ultrafiltration membrane accumulate to a certain degree, the water permeability of the ultrafiltration membrane is affected, the physical cleaning frequency, namely backwashing and air washing are simultaneously performed, can be set according to the water quality and the running time, the backwashing pump is used to send the ultrafiltration membrane outlet water into the ultrafiltration membrane through the backwashing pipeline, the water is discharged from the ultrafiltration membrane, and the aeration blower is opened, the air is used to scrub the ultrafiltration membrane, part of the impurities attached to the ultrafiltration membrane can be cleaned, and the water permeability of the ultrafiltration membrane is restored to a certain degree.

[0016] Further, the chemical cleaning control program also includes acid circulation cleaning: the acid cleaning inlet valve is opened, the acid cleaning outlet valve is opened, the acid cleaning water pump is opened, when the membrane tank liquid reaches the LL liquid level, the cleaning circulation valve is opened, the acid cleaning inlet valve is closed, the liquid circulation cleaning is started, after the acid circulation reaches the set time, the acid cleaning water pump is closed, the cleaning circulation valve and the acid cleaning outlet valve are closed, if the number of times of reuse of the liquid reaches the set number of times, the liquid backflow valve is opened, the acid liquid backflow valve and the acid cleaning inlet valve are opened, the liquid backflow enters the acid cleaning tank, after the liquid backflow is completed, the liquid backflow valve, the acid liquid backflow valve and the acid cleaning inlet valve are closed, the acid circulation program is completed, and the membrane tank rinsing and pipeline flushing program is entered; if the number of times of reuse of the liquid reaches the set number of times, the waste liquid discharge valve is opened, the liquid is discharged into the neutralization tank, after the emptying is completed, the waste liquid discharge valve is closed, the acid circulation program is completed, and the membrane tank rinsing and pipeline flushing program is entered.

[0017] Alkaline cycle washing: open the alkaline cleaning inlet valve, open the alkaline cleaning outlet valve, then open the alkaline cleaning water pump, when the membrane pool liquid reaches the LL level, open the cleaning circulation valve, close the alkaline cleaning inlet valve, start the liquid circulation, after the alkaline cycle reaches the set time, close the alkaline cleaning water pump, then close the cleaning circulation valve and the alkaline cleaning outlet valve, if the number of repeated use of the liquid has not reached the set number, open the liquid backflow valve, then open the alkaline liquid backflow valve and the alkaline cleaning inlet valve, the liquid backflow into the alkaline cleaning water pool, after the liquid backflow is completed, close the liquid backflow valve, the alkaline liquid backflow valve and the alkaline cleaning inlet valve, the alkaline cycle program is completed, and the membrane pool rinsing and pipeline flushing program is entered; if the number of repeated use of the liquid reaches the set number, open the waste liquid discharge valve, the liquid is discharged into the neutralization pool, after the emptying is completed, close the waste liquid discharge valve, the alkaline cycle program is completed, and the membrane pool rinsing and pipeline flushing program is entered.

[0018] Further, it also includes a liquid configuration control program: the chemical cleaning liquid is configured by a certain proportion of the original liquid and ultrafiltration water, the original liquid is added to the corresponding chemical cleaning pool through the metering pump, the liquid is added for a certain time according to the set flow and the concentration of the configured liquid, the chemical cleaning pool is provided with an alkaline liquid level meter and an acid liquid level meter, whether to open the water supplement pump is determined by the measurement value of the alkaline liquid level meter and the acid liquid level meter, the set water supplement level is 2.7m, the water supplement pump is opened below this level and closed when reaching this level, the chemical cleaning pool is provided with an alkaline liquid thermometer, an acid liquid thermometer, an alkaline liquid heater and an acid liquid heater, whether to open the heater is determined by the measurement value of the thermometer, the set temperature of the chemical cleaning liquid is generally above 12-15 degrees Celsius, the original liquid tank includes a sodium hypochlorite tank, a sodium hydroxide tank and a citric acid tank, the tank is provided with a liquid level meter, whether to supplement the original liquid is determined according to the measurement value of the liquid level, the citric acid tank is provided with a citric acid mixing stirrer, the solid citric acid can be stirred and mixed, the chemical cleaning liquid is configured 2 hours before the chemical cleaning, and 30% of the original liquid is supplemented every cycle; taking the configuration of the acid cleaning liquid as an example, open the citric acid liquid valve, open the citric acid metering pump, add the liquid to the acid cleaning pool according to the set flow and time, open the cleaning water valve at this time, then open the cleaning water pump, supplement water to the acid cleaning pool, stop the water supplement when the liquid level of the acid cleaning pool reaches the water supplement level, close the cleaning water pump, then close the cleaning water valve, close the citric acid metering pump when the original liquid reaches the liquid adding time, then close the citric acid liquid valve, stop the liquid supplement, the configuration of the acid cleaning liquid is completed, open the acid liquid heater when the acid liquid thermometer shows that the temperature is lower than the set temperature value, heat the configured cleaning liquid until the set temperature value is reached.

[0019] Further, it also includes the neutralization and control program: the neutralization tank is equipped with pH meter and ORP meter, which can detect the pH and ORP of the waste liquid, and determine whether to start the metering pump according to the measured value. When the pH value is lower than the set value 6, the sodium hydroxide dosing pump is started. When the pH value is higher than the set value 9, the acid dosing pump is started. When the ORP value is higher than the set ORP value 400mv, the reducing agent SBS dosing pump is started. The neutralization tank is equipped with a pipeline mixer, which can fully mix the chemical liquid until the waste liquid in the neutralization tank meets the discharge requirements, and then stop dosing, complete the neutralization control program, and enter the waste liquid discharge control program.

[0020] Further, it also includes the waste liquid discharge control program: the waste water tank and the neutralization tank are equipped with waste water tank liquid level meter and neutralization tank liquid level meter, which can determine whether to start the neutralization tank discharge pump and the waste water tank discharge pump according to the measured value of the liquid level meter. In order to ensure enough reserved space in the neutralization tank and the waste water tank, the discharge pump is started to discharge when the liquid level reaches 1m.

[0021] Further, the automatic control system for chemical cleaning is divided into acid cleaning and alkali cleaning according to the cleaning agent. The acid cleaning agent is hydrochloric acid or citric acid, which mainly removes inorganic substances attached to the ultrafiltration membrane. The alkali cleaning agent is sodium hypochlorite and sodium hydroxide, which mainly removes organic substances attached to the ultrafiltration membrane. According to the cleaning period, it is divided into maintenance cleaning and recovery cleaning. The maintenance cleaning period is short, generally set to once every 1-30 days, the cleaning agent concentration is low, the acid concentration is generally 0.1%-0.5%, the alkali concentration is generally 0.1-0.5%, the cleaning time is short, generally 20-120 minutes, mainly to maintain the water permeability of the ultrafiltration membrane. The recovery cleaning period is long, generally set to once every 3-12 months, the cleaning agent concentration is high, the acid concentration is generally 0.5%-2%, the alkali concentration is generally 0.5-2%, the cleaning time is long, generally 4-24 hours, mainly to restore the optimal water permeability of the ultrafiltration membrane. The concentration of the cleaning agent, the cleaning period and the time need to be determined according to the water quality. According to the cleaning method, it is divided into soaking cleaning and circulating cleaning. The soaking cleaning is to immerse the ultrafiltration membrane in the cleaning liquid, and the cleaning liquid does not permeate the ultrafiltration membrane, which has low operating cost. The circulating cleaning is to make the cleaning liquid permeate the ultrafiltration membrane and then return to the membrane tank for internal circulation, which has better cleaning effect.

[0022] Further, the automatic control system for chemical cleaning uses a circulating and repeated use program, which greatly saves the operating cost. Each new chemical cleaning agent can be used repeatedly for 2-6 times, which is determined according to the on-site cleaning effect.

[0023] Further, the automatic control system adopts PLC control technology, adopts cable connection, takes the computer as an operation terminal, can view the working conditions of each part of the system on the system operation interface, and many parameters of links such as ultrafiltration water production, physical cleaning, chemical cleaning, chemical liquid preparation, chemical liquid neutralization, waste liquid discharge can be set by the operator; The automatic control system is provided with automatic control and manual control two modes, the system automatically runs under the preset parameters under automatic control, and each link can be controlled and adjusted under manual control.

[0024] The ultrafiltration water production control program controls the water inlet and the water outlet through the ultrafiltration membrane, including the water inlet channel, the water inlet gate valve, the ultrafiltration membrane pool, the water production pump, the flow meter, the liquid level meter and the like; The water inlet channel is provided with a thermometer, a liquid level meter and a turbidimeter, an electric gate valve is arranged at the inlet of the ultrafiltration membrane pool, and a static pressure liquid level meter is arranged in the ultrafiltration membrane pool; The ultrafiltration membrane pool water production pipeline is provided with a pressure gauge, a turbidimeter and the like.

[0025] The physical cleaning control program controls the backwashing and air washing of the ultrafiltration membrane, including a Roots blower and a backwashing water pump.

[0026] The chemical cleaning control program controls the acid washing, alkali washing and chemical liquid circulation of the ultrafiltration membrane, including the ultrafiltration membrane pool, the chemical cleaning pool, the cleaning water pump, the liquid level meter and the like; The ultrafiltration membrane pool is connected with an acid cleaning water pump, an alkali cleaning water pump and a chemical liquid return valve; The chemical liquid return valve is connected with an acid liquid inlet valve and an alkali liquid inlet valve through an acid liquid return valve and an alkali liquid return valve respectively; The ultrafiltration membrane pool water production pipeline is connected with a cleaning circulation pipeline and is provided with a cleaning circulation valve.

[0027] The chemical liquid preparation control program controls the dosage and concentration of the cleaning chemical liquid, including a chemical raw liquid tank, a metering pump, a flow meter, a chemical cleaning pool, a chemical cleaning pump, a water supplement pump and a liquid level meter.

[0028] The chemical liquid neutralization control program controls the pH and oxidation-reduction property of the waste liquid in the neutralization pool, including a neutralization pool, a pH meter, an ORP meter, a chemical raw liquid tank and a metering pump; The chemical raw liquid tank includes a sodium hypochlorite raw liquid tank, a sodium hydroxide raw liquid tank and a citric acid raw liquid tank, and is provided with a liquid level meter; The citric acid raw liquid tank is provided with a citric acid mixing stirrer; The neutralization pool is provided with a pipeline mixer.

[0029] The waste liquid discharge control program controls the liquid discharge of the waste water pool and the neutralization pool, including a neutralization pool liquid level meter, a neutralization pool discharge pump, a waste water pool liquid level meter and a waste water pool discharge pump.

[0030] The main advantage of the high-efficiency automatic control method for the submerged ultrafiltration membrane is that:

[0031] First, the automatic control method provided is for the purpose of meeting actual engineering application, is modified and improved in each link in long-term practical application process, and finally has the full-system one-key operation, each link has automatic and manual two-gear optional, specific parameters can be adjusted at any time and other distinct advantages of the immersed ultrafiltration membrane full-process efficient automatic control system.

[0032] Second, the water recovery rate obtained by the system is high, the water quality is stable, the service life of the ultrafiltration membrane is long, the chemical cleaning agent recycling rate is high, the system operation cost is greatly reduced, the system has high automation degree, can improve the processing efficiency and safety of the immersed ultrafiltration membrane system, and saves manpower.

[0033] Third, the system detects the transmembrane pressure difference of the ultrafiltration membrane in real time, and is provided with a critical alarm device, can effectively clean the ultrafiltration membrane physically and chemically in time, so as to ensure the best water permeability, and effectively prolong the service life of the ultrafiltration membrane.

[0034] Fourth, the chemical cleaning agent of the system adopts a recycling program, the water recovery rate of the system is high, and the operation cost is low. DETAILED DESCRIPTION

[0035] Figure 1 The immersed ultrafiltration membrane efficient automatic control method process flow of the application Figure 1 .

[0036] Figure 2 The immersed ultrafiltration membrane efficient automatic control method process flow of the application Figure 2 .

[0037] Figure 3 The immersed ultrafiltration membrane efficient automatic control method chemical cleaning process flow chart of the application.

[0038] Figure 4 The immersed ultrafiltration membrane efficient automatic control method waste liquid discharge process flow chart of the application.

[0039] In the figure, 1-temperature gauge, 2-liquid level gauge, 3-inlet water turbidity meter, 4-outlet water turbidity meter, 5-backwashing pump, 6-cleaning water supplement pump, 7-inlet water gate valve, 8-inlet air valve, 9-cleaning medicine inlet valve, 10-static pressure liquid level gauge, 11-vacuum jet, 12-pressure gauge, 13-backwashing valve, 14-cleaning circulation valve, 15-water production valve, 16-ultrafiltration water production pump, 17-medicine backflow valve, 18-waste water discharge valve, 19-waste liquid discharge valve, 20-sodium hypochlorite raw liquid level gauge, 21-sodium hypochlorite raw liquid tank, 22-sodium hydroxide raw liquid level gauge, 23-sodium hydroxide raw liquid tank, 24-citric acid raw liquid level gauge, 25-citric acid raw liquid tank, 26-citric acid mixing stirrer, 27-alkali liquid supplement valve, 28-sodium hydroxide medicine valve, 29-alkali liquid level gauge, 30-alkali liquid temperature gauge, 31-alkali liquid heater, 32-alkali liquid emptying valve, 33-alkali cleaning liquid inlet valve, 34-alkali liquid backflow valve, 35-alkali cleaning water pump, 36-sodium hypochlorite metering pump, 37-alkali liquid mixing valve, 38-alkali cleaning liquid outlet valve, 39-sodium hydroxide neutralization valve, 40-citric acid medicine valve, 41-acid liquid supplement valve, 42-acid liquid level gauge, 43-acid liquid temperature gauge, 44-acid liquid heater, 45-acid liquid emptying valve, 46-acid liquid neutralization valve, 47-acid cleaning liquid inlet valve, 48-acid liquid backflow valve, 49-acid cleaning water pump, 50-sodium hydroxide metering pump, 51-acid liquid mixing valve, 52-acid cleaning liquid outlet valve, 53-citric acid metering pump, 54-PH meter, 55-neutralization tank liquid level gauge, 56-ORP meter, 57-neutralization tank discharge pump, 58-waste water tank liquid level gauge, 59-waste water tank discharge pump. DETAILED DESCRIPTION

[0040] For the convenience of understanding of those skilled in the art, the present application is further described below in combination with examples and drawings.

[0041] As Figures 1-4 shown, it is the main process flow chart of the high-efficiency automatic control method and system of the present immersed ultrafiltration membrane. The process route is as follows:

[0042] I. Ultrafiltration water production control program

[0043] The water inlet of the ultrafiltration membrane tank flows from the water inlet channel. The water inlet channel is provided with a thermometer 1, a liquid level meter 2, a water inlet turbidity meter 3 and a water outlet turbidity meter 4 for detecting the water quality and quantity of the water inlet. The water production flow of the membrane tank can be set according to the measured water temperature, liquid level and turbidity. When the temperature is lower than 15℃, the water production flow of the membrane tank is reduced to 80% of the designed flow. When the temperature is higher than 15℃, the water production flow is the designed flow. When the liquid level is higher than 2m, the water production flow of the membrane tank is increased. When the liquid level is lower than 2m, the water production flow is reduced. When the turbidity is higher than 5NTU, the water production flow is reduced. When the turbidity is lower than 5NTU, the water production flow is increased. An electric gate valve 7 is arranged at the inlet of the ultrafiltration membrane tank. The gate valve opening degree is automatically controlled by the PLC to adjust the water inlet flow of the ultrafiltration membrane tank. A static pressure liquid level meter 10 is arranged in the ultrafiltration membrane tank. Whether the water production pump 16 is started and whether the water inlet gate valve 7 is opened are determined according to the measured value of the static pressure liquid level meter 10. When the liquid level of the membrane tank is lower than L level, the water inlet gate valve 7 is opened. When the liquid level of the membrane tank is higher than H level, the water inlet gate valve 7 is closed. When the liquid level of the membrane tank is higher than L level, the vacuum jet 11 is opened for about 10-30s and then closed. Then the water production valve 15 is opened. Subsequently, the water production pump 16 is started. The system starts to produce water. When the liquid level of the membrane tank is lower than LL level, the water production pump 16 is stopped and the water production valve 15 is closed. The water production program is ended. When the system is normally operated, the water production time is set according to a fixed period. Generally, the fixed period is 20-50 minutes. The water production is stopped when the set period is reached.

[0044] ⅡPhysical cleaning control program

[0045] The ultrafiltration membrane is physically cleaned once every water production time. Generally, the water production time is 20-50 minutes. The backwashing gas washing is simultaneously performed. Firstly, the liquid level of the membrane tank is lowered for filtration. The water inlet gate valve 7 is closed. The membrane tank continues to produce water. When the liquid level of the membrane tank is lower than LL level, the water production pump 16 is stopped and the water production valve 15 is closed. Subsequently, the backwashing valve 13 is opened. The backwashing pump 5 is also opened. The gas washing valve 8 is opened. The Roots blower is opened. The backwashing pump 5 and the Roots blower are closed after about 60s. The backwashing valve 13 and the gas washing valve 8 are closed. The physical cleaning is ended. The water inlet gate valve 7 is opened. The system enters the water production state again. After a plurality of times of physical cleaning, the specific number of times is determined according to the water quality. Generally, the number of times is 3-6. The backwashing wastewater in the ultrafiltration membrane tank is discharged. The wastewater discharge valve 18 is opened. The wastewater is discharged into the wastewater discharge tank. When the membrane tank is emptied, the wastewater discharge valve 18 is closed. The water inlet gate valve 7 is opened. The system enters the water production program again.

[0046] ⅢChemical cleaning control program

[0047] The outlet pipeline of the ultrafiltration membrane tank is equipped with a pressure gauge 12. The pressure gauge 12 measures the value of the transmembrane pressure difference of the ultrafiltration membrane, which reflects the water permeability of the ultrafiltration membrane and can determine whether the ultrafiltration membrane needs to be chemically cleaned. According to the on-site debugging, the fixed period of maintenance cleaning and recovery cleaning can be set, and the transmembrane pressure difference value is used as the reference value and protection value for cleaning the ultrafiltration membrane. When chemical cleaning is performed, different implementation procedures are used according to the type and cleaning method of the cleaning agent, which are described as follows:

[0048] ① Acid soaking: after the backwashing wastewater is emptied, the wastewater discharge valve 18 is closed, the acid cleaning inlet valve 47 is opened, the acid cleaning outlet valve 52 is opened, and the acid cleaning water pump 49 is started. When the liquid level of the membrane tank reaches LL, the acid cleaning water pump 49 is stopped, the acid cleaning inlet valve 47 and the acid cleaning outlet valve 52 are closed, and the acid soaking is completed. If the number of times of reusing the cleaning agent does not reach the set number of times, the cleaning agent is returned to the acid cleaning tank by opening the cleaning agent return valve 17, the acid liquid return valve 48, and the acid cleaning inlet valve 47. After the cleaning agent is returned, the valves are closed, and the acid soaking program is completed. If the number of times of reusing the cleaning agent reaches the set number of times, the cleaning agent is discharged into the neutralization tank by opening the discharge valve 19. After the discharge is completed, the discharge valve 19 is closed, and the acid soaking program is completed.

[0049] ② Acid circulation: after the backwashing wastewater is emptied, the wastewater discharge valve 18 is closed, the acid cleaning inlet valve 47 is opened, the acid cleaning outlet valve 52 is opened, and the acid cleaning water pump 49 is started. When the liquid level of the membrane tank reaches LL, the circulation valve 14 is opened, the acid cleaning inlet valve 47 is closed, and the cleaning agent circulation is started. After the acid circulation reaches the set time, the acid cleaning water pump 49 is closed, the circulation valve 14 and the acid cleaning outlet valve 52 are closed, and the cleaning agent is returned to the acid cleaning tank by opening the cleaning agent return valve 17, the acid liquid return valve 48, and the acid cleaning inlet valve 47. After the cleaning agent is returned, the valves are closed, and the acid circulation program is completed. If the number of times of reusing the cleaning agent reaches the set number of times, the cleaning agent is discharged into the neutralization tank by opening the discharge valve 19. After the discharge is completed, the discharge valve 19 is closed, and the acid circulation program is completed.

[0050] ③Alkaline soak washing: after the backwashing waste water is emptied, the waste water discharge valve 18 is closed, the alkaline cleaning liquid inlet valve 33 is opened, the alkaline cleaning liquid outlet valve 38 is opened, and the alkaline cleaning water pump 35 is opened. When the membrane tank liquid reaches the LL level, the medicine feeding is stopped, the alkaline cleaning water pump 35 is closed, and the alkaline cleaning liquid inlet valve 33 and the alkaline cleaning liquid outlet valve 38 are closed. After the alkaline soaking reaches the set time, if the number of repeated use of the liquid medicine does not reach the set number, the liquid medicine backflow valve 17 is opened, the alkaline liquid backflow valve 34 and the alkaline cleaning liquid inlet valve 33 are opened, and the liquid medicine backflows into the alkaline cleaning water tank. After the liquid medicine backflow is completed, the liquid medicine backflow valve 17, the alkaline liquid backflow valve 34 and the alkaline cleaning liquid inlet valve 33 are closed, the alkaline soaking program is completed, and the rinsing program is entered. If the number of repeated use of the liquid medicine reaches the set number, the discharge valve 19 is opened, the liquid medicine is discharged into the neutralization tank, and after the emptying is completed, the discharge valve 19 is closed. The alkaline soaking program is completed, and the membrane tank rinsing and pipeline flushing program is entered.

[0051] ④Alkaline circulation washing: after the backwashing waste water is emptied, the waste water discharge valve 18 is closed, the alkaline cleaning liquid inlet valve 33 is opened, the alkaline cleaning liquid outlet valve 38 is opened, and the alkaline cleaning water pump 35 is opened. When the membrane tank liquid reaches the LL level, the circulation valve 14 is opened, the alkaline cleaning liquid inlet valve 33 is closed, and the liquid medicine circulation is started. After the alkaline circulation reaches the set time, the alkaline cleaning water pump 35 is closed, and the circulation valve 14 and the alkaline cleaning liquid outlet valve 38 are closed. If the number of repeated use of the liquid medicine does not reach the set number, the liquid medicine backflow valve 17 is opened, the alkaline liquid backflow valve 34 and the alkaline cleaning liquid inlet valve 33 are opened, and the liquid medicine backflows into the alkaline cleaning water tank. After the liquid medicine backflow is completed, the liquid medicine backflow valve 17, the alkaline liquid backflow valve 34 and the alkaline cleaning liquid inlet valve 33 are closed, the alkaline circulation program is completed, and the rinsing program is entered. If the number of repeated use of the liquid medicine reaches the set number, the discharge valve 19 is opened, the liquid medicine is discharged into the neutralization tank, and after the emptying is completed, the discharge valve 19 is closed. The alkaline circulation program is completed, and the membrane tank rinsing and pipeline flushing program is entered.

[0052] Membrane tank rinsing and pipeline flushing: the water inlet gate valve 7 is opened. When the membrane tank liquid level reaches the LL level, the water inlet gate valve 7 is closed, the circulation valve 14 is opened, the alkaline cleaning liquid outlet valve 38 (after alkaline cleaning) or the acid cleaning liquid outlet valve 52 (after acid cleaning) is opened, and the alkaline cleaning water pump 35 (after alkaline cleaning) or the acid cleaning water pump 49 (after acid cleaning) is opened. The water in the membrane tank is circulated between the membrane tank, the water production pipeline, the liquid medicine backflow pipe and the medicine feeding pipe, the membrane tank is rinsed and the pipeline is flushed, and the time is about 2-10 min. Then the corresponding cleaning water pump is closed, the circulation valve and the corresponding cleaning liquid inlet and outlet valve are closed, the discharge valve 19 is opened, the waste liquid is discharged into the neutralization tank, and after the membrane tank is emptied, the discharge valve 19 is closed. The above operation is repeated once, and the membrane tank rinsing and pipeline flushing process is carried out twice. After the membrane tank rinsing and pipeline flushing is completed, the water inlet gate valve 7 is opened. When the membrane tank liquid level reaches the L level, the membrane tank enters the ultrafiltration water production program.

[0053] Membrane pool rinsing and pipeline flushing program is the subsidiary program of chemical cleaning control program, mainly to reduce the residual concentration of chemical cleaning agent in the membrane pool, and to clean the water production pipeline, medicine pipeline and liquid reflux pipeline to ensure the water quality.

[0054] Ⅳ Medicine liquid configuration control program

[0055] The chemical cleaning liquid is configured by the medicine original liquid and the ultrafiltration water in a certain proportion. The medicine original liquid is added to the chemical cleaning pool through the metering pump. The metering pump includes: sodium hypochlorite metering pump 36, sodium hydroxide metering pump 50 or citric acid metering pump 53.

[0056] The dosing time is set according to the set flow and the concentration of the configured medicine. The chemical cleaning pool is equipped with liquid level meters 29, 42. Whether to start the water supplement pump 6 is determined by the measurement value of the liquid level meter 29, 42. The chemical cleaning pool is equipped with thermometers 30, 43 and heaters 31, 44. Whether to start the heater is determined by the measurement value of the thermometer. Generally, the set temperature of the chemical cleaning agent is above 12-15 degrees Celsius. The medicine original liquid tanks 21, 23, 25 are equipped with liquid level meters 20, 22, 24. Whether to supplement the medicine original liquid can be determined according to the liquid level measurement value. When the liquid level is lower than 1m, the medicine needs to be supplemented. The original liquid tank 25 is equipped with a stirrer 26, which can stir and mix the citric acid solid. The chemical cleaning liquid configuration time is generally 2h before chemical cleaning. 30% medicine original liquid needs to be supplemented every cycle. Taking the configuration of acid cleaning liquid as an example, open the valve 40, open the citric acid metering pump 53, add medicine to the acid cleaning pool according to the set flow and set time. At this time, open the cleaning water supplement valve 41, and then open the cleaning water supplement pump 6 to supplement water to the acid cleaning pool. The set water level is 2.7m. When the liquid level of the acid cleaning pool reaches this level, stop the water supplement, close the cleaning water pump 6, and then close the cleaning water supplement valve 41. When the citric acid original liquid reaches the dosing time, close the citric acid metering pump 53, and then close the valve 40 to stop the medicine supplement. The configuration of the acid cleaning liquid is completed. When the thermometer 43 shows that the temperature is lower than the set temperature value, open the heater 44 to heat the configured cleaning liquid until the set temperature value is reached.

[0057] Ⅴ Medicine liquid neutralization control program

[0058] The neutralization pool is equipped with a PH meter 54 and an ORP meter 56, which can detect the acidity and alkalinity and the oxidation and reduction of the waste liquid. Whether to start the metering pump is determined by the measurement value. When the PH value is lower than the set value, the alkali dosing pump is started. When the PH value is higher than the set value, the acid dosing pump is started. When the ORP value is higher than a certain oxidation reduction potential value, the reducing agent dosing pump is started. The neutralization pool is equipped with a pipeline mixer, which can fully mix and react the medicine liquid until the waste liquid of the neutralization pool meets the discharge requirements, the dosing is stopped, the neutralization control program is completed, and the waste liquid discharge control program is entered.

[0059] Ⅵ Waste liquid discharge control program

[0060] The wastewater tank and the neutralization tank are provided with a wastewater tank liquid level meter 58 and a neutralization tank liquid level meter 55, and whether to start the neutralization tank discharge pump 57 and the wastewater tank discharge pump 59 is determined according to the measurement value of the liquid level meter. In order to ensure sufficient reserved space of the neutralization tank and the wastewater tank, the discharge pump is generally started to discharge when the liquid level reaches a lower value.

[0061] The water recovery rate obtained by the system is high, the water quality is stable, the service life of the ultrafiltration membrane is long, the recycling rate of the chemical cleaning agent is high, the operation cost of the system is greatly reduced, the system has high automation degree, and the processing efficiency and safety of the submerged ultrafiltration membrane system can be improved, and manpower can be saved.

[0062] The above only describes the preferred embodiments of the present application, and does not limit the scope of the present application. Those skilled in the art can make various changes and decorations according to the principles and technical features of the present application, which should be covered by the protection scope defined in the present claims.

Claims

1. A highly efficient automatic control method for submerged ultrafiltration membranes, characterized in that, include, Ultrafiltration permeate control procedure: Water flows into the ultrafiltration membrane tank from the inlet channel, which is equipped with a thermometer, level gauge, and turbidity meter to detect the quality and quantity of the inlet water. The permeate flow rate of the membrane tank is set by analyzing the measured inlet water temperature, level, and turbidity values. The ultrafiltration membrane tank is equipped with a hydrostatic level gauge, and the measurement value of the hydrostatic level gauge is used to determine whether to start the permeate pump and whether to open the inlet gate valve. When the liquid level in the membrane tank is lower than the L level, the inlet gate valve opens; When the membrane tank liquid level is higher than the H level, the inlet gate valve closes. When the membrane tank liquid level is higher than the L level, the vacuum jet valve opens and closes after 10-30 seconds. Then the product water valve opens, followed by the product water pump, and the system starts producing water. When the membrane tank level is lower than the LL level, the permeate pump is turned off, the permeate valve is closed, and the permeate program ends. When the influent is stable, permeate production stops according to the time setting. The LL level is a protective level to prevent damage to the ultrafiltration membrane due to dryness and to prevent damage to the permeate pump due to dry running. The L level is the ultrafiltration permeate start-up level, and the H level is the inlet stop level to prevent overflow caused by excessive water entering the membrane tank. Chemical cleaning control procedure: The ultrafiltration membrane tank outlet pipe is equipped with a pressure gauge. The pressure gauge reading can be used to calculate the transmembrane pressure difference of the ultrafiltration membrane with the hydrostatic level gauge reading. When the system is running normally, the frequency of maintenance cleaning and recovery cleaning is set according to a fixed water production cycle. Acid Immersion Washing: Open the acid inlet valve, open the acid outlet valve, and then start the acid cleaning water pump. When the solution in the membrane tank reaches the LL level, stop the inlet, close the acid cleaning water pump, close the acid cleaning inlet valve, and open the acid cleaning outlet valve. After the acid immersion reaches the set time, if the solution has not been reused a set number of times, open the solution return valve, then open the acid return valve and the acid cleaning inlet valve. The solution will flow back into the acid cleaning water tank. After the solution return is complete, close the solution return valve, acid return valve, and acid cleaning inlet valve. The acid immersion process is complete, and the membrane tank rinsing and pipeline flushing process begins. If the solution has been reused a set number of times, open the waste liquid discharge valve, and the solution will be discharged into the neutralization tank. After the tank is emptied, close the waste liquid discharge valve. The acid immersion process is complete, and the membrane tank rinsing and pipeline flushing process begins. Alternatively, alkaline soaking: Open the alkaline cleaning inlet valve, open the alkaline cleaning outlet valve, and then start the alkaline cleaning water pump. When the solution in the membrane tank reaches the LL level, stop the chemical feeding, turn off the alkaline cleaning water pump, and then close the alkaline cleaning inlet valve and the alkaline cleaning outlet valve. After the alkaline soaking reaches the set time, if the number of times the solution can be reused has not reached the set number, open the solution return valve, and then open the alkaline solution return valve and the alkaline cleaning inlet valve. The solution will flow back into the alkaline cleaning water tank. After the solution return is complete, close the solution return valve, the alkaline solution return valve, and the alkaline solution inlet valve. The alkaline soaking process is complete, and the membrane tank rinsing and pipeline flushing process begins. If the number of times the solution can be reused has reached the set number, open the waste liquid discharge valve, and the solution will be discharged into the neutralization tank. After the tank is emptied, close the waste liquid discharge valve. The alkaline soaking process is complete, and the membrane tank rinsing and pipeline flushing process begins. Membrane tank rinsing and pipeline flushing: Open the inlet gate valve. When the membrane tank level reaches LL, close the inlet gate valve and open the cleaning circulation valve. When the cleaning is alkaline, open the alkaline cleaning outlet valve and then start the alkaline cleaning water pump. When the cleaning is acidic, open the acidic cleaning outlet valve and then start the acidic cleaning water pump. The water in the membrane tank circulates between the membrane tank, permeate pipeline, chemical return pipe, and chemical inlet pipe to flush the pipeline for 2-10 minutes. Then, close the corresponding cleaning water pump, the cleaning circulation valve, and the corresponding cleaning outlet valve. Open the waste liquid discharge valve to discharge the rinsing solution into the neutralization tank. After the membrane tank is emptied, close the waste liquid discharge valve. After two rounds of membrane tank rinsing and pipeline flushing, the membrane tank is ready. Open the inlet gate valve. When the membrane tank level reaches L, the membrane tank enters normal permeate water production. Physical cleaning control procedure: The ultrafiltration membrane undergoes physical cleaning once every certain period of water production, i.e., backwashing and air washing are carried out simultaneously. First, the ultrafiltration membrane tank is filtered by lowering the liquid level, and the inlet gate valve is closed. The membrane tank continues to produce water. When the liquid level in the membrane tank is lower than the LL liquid level, the water pump and water valve are closed. Then, the backwash valve is opened, followed by the backwash pump and the air washing valve. Then, the Roots blower is opened. After 50-70 seconds, the backwash pump and the Roots blower are turned off. Then, the backwash valve and the air washing valve are closed. The physical cleaning is completed. The inlet gate valve is opened, and the system enters the water production state again. After performing a set number of physical cleaning cycles, open the wastewater discharge valve to discharge the backwash wastewater in the ultrafiltration membrane tank into the wastewater discharge tank. Once the membrane tank is emptied, close the wastewater discharge valve and open the inlet gate valve, and the system will then enter the water production program. After the backwash wastewater of the physical cleaning control program is drained, close the wastewater discharge valve and then start the chemical cleaning control program. Drug solution preparation control procedure: The chemical concentrate is added to the chemical cleaning tank through a metering pump. The dosing time is set according to the set flow rate and the concentration of the prepared chemical. The chemical cleaning tank is equipped with an alkaline liquid level gauge and an acid liquid level gauge. The measurement value of the alkaline liquid level gauge and the acid liquid level gauge determines whether to turn on the water supply pump. The chemical cleaning tank is equipped with an alkaline liquid thermometer, an acid liquid thermometer, an alkaline liquid heater, and an acid liquid heater. If the measurement value of the alkaline liquid thermometer or the acid liquid thermometer is not above 15 degrees Celsius, the alkaline liquid heater and the acid liquid heater are turned on. The concentrate tank is equipped with a level gauge. The level measurement can determine whether the concentrate needs to be replenished. The citric acid concentrate tank in the concentrate tank is equipped with a citric acid mixer to stir and mix the solid citric acid. The chemical cleaning solution is prepared 2 hours before chemical cleaning. 30% concentrate is added to the solution after each cycle.

2. The efficient automatic control method for submerged ultrafiltration membranes according to claim 1, characterized in that, The chemical cleaning control procedure also includes acid circulation washing: Open the acid cleaning inlet valve, open the acid cleaning outlet valve, and then start the acid cleaning water pump. When the solution in the membrane tank reaches the LL level, open the cleaning circulation valve and close the acid cleaning inlet valve to begin the solution circulation washing. After the acid circulation reaches the set time, turn off the acid cleaning water pump, and then close the cleaning circulation valve and the acid cleaning outlet valve. If the number of times the solution can be reused has not reached the set number, open the solution return valve, and then open the acid return valve and the acid cleaning inlet valve. The solution flows back into the acid cleaning tank. After the solution return is complete, close the solution return valve, acid return valve, and acid cleaning inlet valve. The acid circulation procedure is complete, and the membrane tank rinsing and pipeline flushing procedure begins. If the number of times the solution can be reused has reached the set number, open the waste liquid discharge valve, and the solution is discharged into the neutralization tank. After the tank is emptied, close the waste liquid discharge valve. The acid circulation procedure is complete, and the membrane tank rinsing and pipeline flushing procedure begins. Alkali circulation washing: Open the alkaline cleaning inlet valve, open the alkaline cleaning outlet valve, and then start the alkaline cleaning water pump. When the solution in the membrane tank reaches the LL level, open the cleaning circulation valve and close the alkaline cleaning inlet valve to start the solution circulation. After the alkaline circulation reaches the set time, turn off the alkaline cleaning water pump, and then close the cleaning circulation valve and the alkaline cleaning outlet valve. If the number of times the solution can be reused has not reached the set number, open the solution return valve, and then open the alkaline return valve and the alkaline cleaning inlet valve. The solution will flow back into the alkaline cleaning water tank. After the solution return is complete, close the solution return valve, the alkaline return valve, and the alkaline cleaning inlet valve. The alkaline circulation program is complete, and the membrane tank rinsing and pipeline flushing program begins. If the number of times the solution can be reused has reached the set number, open the waste liquid discharge valve and discharge the solution into the neutralization tank. After the tank is emptied, close the waste liquid discharge valve. The alkaline circulation program is complete, and the membrane tank rinsing and pipeline flushing program begins.

3. The efficient automatic control method for submerged ultrafiltration membranes according to claim 1, characterized in that, It also includes a drug neutralization control procedure: The neutralization tank is equipped with a pH meter and an ORP meter. The metering pump is activated based on the measured values. When the pH value is lower than the set value, the sodium hydroxide dosing pump is activated. When the pH value is higher than the set value, the acid dosing pump is activated. When the ORP value is higher than a certain oxidation-reduction potential value, the reducing agent dosing pump is activated. The pipeline mixer in the neutralization tank fully mixes the chemical solution until the waste liquid in the neutralization tank meets the discharge requirements. Then, the dosing stops, and the neutralization control program is completed.

4. The efficient automatic control method for submerged ultrafiltration membranes according to claim 3, characterized in that, It also includes a wastewater discharge control procedure: the wastewater tank and neutralization tank are equipped with wastewater tank level gauges and neutralization tank level gauges. When the liquid level reaches a low value, the neutralization tank discharge pump and the wastewater tank discharge pump are turned on to discharge the wastewater.

5. The efficient automatic control method for submerged ultrafiltration membranes according to claim 1, characterized in that, The cleaning cycle is divided into maintenance cleaning and restorative cleaning. Maintenance cleaning is set to be done once every 1-30 days, with an acid concentration of 0.1%-0.5% and an alkali concentration of 0.1%-0.5% in the cleaning agent, and a cleaning time of 20-120 minutes. Restorative cleaning is set to be done once every 3-12 months, with an acid concentration of 0.5%-2% and an alkali concentration of 0.5%-2% in the cleaning agent, and a cleaning time of 4-24 hours.

6. The efficient automatic control method for submerged ultrafiltration membranes according to claim 1, characterized in that: Using a computer as the operating terminal, it has two modes: automatic control and manual control. In automatic control, it runs automatically according to preset parameters. In manual control, the ultrafiltration water production, physical cleaning, chemical cleaning, chemical solution preparation, chemical solution neutralization, and waste liquid discharge can be adjusted.

7. A system for the efficient automatic control method of an submerged ultrafiltration membrane according to any one of claims 1 to 6, characterized in that: The ultrafiltration permeate control program controls the inlet water and the outlet water through the ultrafiltration membrane. It includes an inlet channel, an inlet gate valve, an ultrafiltration membrane tank, a permeate pump, a flow meter, and a level gauge. The inlet channel is equipped with a thermometer, a level gauge, and a turbidity meter. An electric gate valve is installed at the inlet of the ultrafiltration membrane tank, and a hydrostatic level gauge is installed inside the ultrafiltration membrane tank. The physical cleaning control program controls the ultrafiltration membrane to perform backwashing and air washing, including the Roots blower and backwash water pump; The chemical cleaning control program controls the ultrafiltration membrane for acid washing, alkali washing, and chemical solution circulation. It includes an ultrafiltration membrane tank, a chemical cleaning tank, a chemical cleaning pump, and a level gauge. The outlet pipe of the ultrafiltration membrane tank is equipped with a pressure gauge. The ultrafiltration membrane tank is connected to an acid cleaning pump, an alkali cleaning pump, and a chemical solution return valve. After the chemical solution return valve, it is connected to the acid cleaning inlet valve and the alkali cleaning inlet valve via acid and alkali return valves, respectively. A cleaning circulation valve is also installed inside the ultrafiltration membrane tank. The chemical solution preparation control program controls the dosage and concentration of the cleaning solution, including the chemical concentrate tank, metering pump, flow meter, chemical cleaning tank, chemical cleaning pump, water replenishment pump, and level gauge; The chemical neutralization control procedure controls the pH and redox properties of the waste liquid in the neutralization tank, including the neutralization tank, pH meter, ORP meter, chemical concentrate tank, and metering pump; the chemical concentrate tanks include sodium hypochlorite concentrate tank, sodium hydroxide concentrate tank, and citric acid concentrate tank, and each concentrate tank is equipped with a level gauge; the citric acid concentrate tank is equipped with a citric acid mixing agitator; the neutralization tank is equipped with a pipeline mixer; The waste liquid discharge control program controls the liquid discharge from the wastewater tank and neutralization tank, including the neutralization tank level gauge, neutralization tank discharge pump, wastewater tank level gauge, and wastewater tank discharge pump.

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