Integrated intelligent modular water purification system and operation control method thereof

Abstract

The application discloses an integrated intelligent membrane water purification equipment and a running control method thereof, and belongs to the technical field of water treatment. The equipment comprises a pretreatment module, a multi-stage membrane filtration module, an intelligent disinfection module, a central control module and an integrated clean water warehouse, and each module is designed in a modular integrated manner. The pretreatment module adopts a partitioned dosing and precipitation structure, and is provided with a spiral dosing pipe and a high-pressure flushing system at the bottom. The membrane filtration module adopts a 1+N redundant configuration, integrates ultrafiltration / nanofiltration / reverse osmosis composite membrane components, and is provided with an online water quality monitoring and automatic cleaning unit. The clean water warehouse adopts a Dacromet-oxidation film composite corrosion prevention process, and is provided with a built-in variable frequency water supply pump set. The control method realizes self-adaptive adjustment of raw water quality, membrane pollution early warning and intelligent backwashing control through a PLC. The application can reduce the equipment area by more than 40%, reduce energy consumption by 25%, has a 24-hour continuous operation capacity, and can make the water quality reach the GB 5749-2022 standard, and is suitable for urban centralized water supply and emergency water supply scenes.

Description

Technical Field

[0001] This invention belongs to the field of drinking water treatment technology, specifically relating to an integrated intelligent modular water purification system and its operation control method. More specifically, this invention relates to a modular water purification device that highly integrates pretreatment, membrane filtration, disinfection, water supply, and intelligent control functions, as well as an operation control method based on this device to achieve adaptive water quality adjustment, membrane fouling early warning, and intelligent cleaning. It can be widely applied in scenarios such as centralized urban water supply, rural safe drinking water projects, emergency water supply, and small-scale community water supply. Background Technology

[0002] With the development of society and economy and the improvement of people's living standards, people have increasingly strict requirements for drinking water quality. Traditional water purification plants usually consist of multiple structures such as independent sedimentation tanks, filtration tanks, clear water tanks, pump rooms, and chemical dosing rooms. They have problems such as large land area, long construction period, high investment cost, low degree of automation, and complex operation and maintenance management, making it difficult to meet the needs of efficient water resource utilization and water quality safety assurance in the process of urbanization.

[0003] To address the shortcomings of traditional water treatment plants, integrated water purification equipment has emerged. Existing integrated water purification equipment, by combining multiple treatment units, reduces floor space and improves construction efficiency to some extent. However, these devices still have many drawbacks: membrane module configurations are simple and lack redundancy; if a membrane module becomes fouled or malfunctions, the entire system will stop operating, compromising continuous water supply; the pretreatment unit's chemical mixing effect is poor, resulting in low sedimentation efficiency and significant fluctuations in the raw water quality entering the membrane filtration unit, accelerating membrane fouling; membrane cleaning methods are simple, often relying on physical backwashing or chemical cleaning, with limited cleaning effectiveness and short membrane lifespan; the clear water tank lacks sufficient corrosion resistance, making it prone to corrosion with prolonged use, affecting water quality safety and equipment lifespan; and the level of automation is low, relying heavily on manual operation and experience-based judgment, unable to automatically adjust operating parameters according to changes in raw water quality, making it difficult to guarantee operating efficiency and the stability of effluent water quality.

[0004] For example, patent CN201110350551.7 discloses a water purification plant device whose membrane filtration unit is only equipped with a single membrane module, lacking backup membrane modules and intelligent switching functions. When the membrane module is contaminated or damaged, the machine needs to be shut down for replacement, affecting the continuity of water supply. Its clear water tank uses ordinary anti-corrosion coating, which has limited anti-corrosion performance and a short service life. In addition, the device is not equipped with a complete online monitoring and intelligent control unit, and cannot realize water quality adaptive adjustment and membrane fouling early warning.

[0005] Therefore, developing a membrane water purification device and its operation control method that is highly integrated, intelligent, stable and reliable in operation, and easy to maintain is of great significance for improving drinking water treatment efficiency and ensuring water supply security. Summary of the Invention

[0006] The present invention aims to overcome the above-mentioned defects of the prior art and provide an integrated intelligent membrane water purification device and its operation control method with high integration, strong intelligence, good operational stability and convenient maintenance. Attached Figure Description

[0007] Figure 1 is a schematic diagram of the overall structure of the integrated intelligent modular water purification system of the present invention.

[0008] To achieve the above objectives, the present invention adopts the following technical solution.

[0009] Pretreatment Module: Adopting a zoned design, this module comprises four independent sedimentation units, capable of parallel or alternating operation. Each sedimentation unit is equipped with an independent inlet pipe, a spiral dosing pipe, a high-pressure rotary flushing device, and an overflow weir. The spiral dosing pipe design ensures efficient mixing of the chemicals with the raw water. Made of 316L stainless steel, the pipe's outer wall features staggered dosing holes with a diameter of 3-5mm and a spacing of 15-20mm, improving dosing uniformity by over 40%. The high-pressure rotary flushing device (operating pressure 0.3-0.5MPa) thoroughly removes bottom sludge, achieving a flushing efficiency 2-3 times that of traditional fixed flushing. The pretreatment module's operating mode can be flexibly adjusted according to the raw water quality. When the raw water quality is good, 2-3 sedimentation units can be activated; when the raw water quality is poor, all four sedimentation units are activated, extending the sedimentation time or increasing the chemical dosage to ensure pretreatment effectiveness.

[0010] Membrane filtration module: Utilizing a 1+N redundancy configuration (N=1-3), the number of standby membrane modules can be flexibly configured according to treatment scale and water supply reliability requirements. The membrane modules employ composite membrane elements with a molecular weight cutoff of 1000-100000 Da, and ultrafiltration, nanofiltration, or reverse osmosis membrane modules can be selected based on effluent quality requirements. The membrane module spacing is 8-12cm, ensuring good heat dissipation and maintenance space. The membrane elements adopt an external pressure hollow fiber structure, with a filtration accuracy of 0.001-0.1μm and an operating pressure of 0.1-0.6MPa, featuring high flux and excellent anti-fouling performance. A cleaning water storage tank is located at the bottom of the membrane filtration module, equipped with an ultrasonic cleaning device with a frequency of 20-40kHz and a chemical cleaning system, forming a combined cleaning unit that significantly improves membrane cleaning efficiency. Pressure sensors, turbidity sensors, and automatic switching valves are installed at the inlet and outlet ends to achieve real-time monitoring of the membrane module's operating status and seamless switching between main and standby membrane modules, with a switching time ≤10 seconds, ensuring continuous water supply.

[0011] The intelligent disinfection module includes a chlorine dioxide generator, an online residual chlorine monitor, and an automatic dosing unit, connected in series with the permeate pipeline of the membrane filtration module. The chlorine dioxide generator uses electrolysis to produce chlorine dioxide, with a gas production rate of 50-500 g / h and a dosing accuracy of ±5%. The online residual chlorine monitor monitors the residual chlorine concentration in the permeate in real time and feeds the signal back to the central control module. The PID control algorithm adjusts the dosing amount of the disinfectant to ensure that the residual chlorine concentration remains stable within the range of 0.05-0.8 mg / L, guaranteeing that the effluent microbiological indicators meet the standards.

[0012] Central Control Module: Employs a PLC control system integrating a touchscreen, data acquisition unit, and remote communication interface. The data acquisition unit can collect real-time parameters such as raw water turbidity, pH, temperature, COD, ammonia nitrogen concentration, membrane inlet and outlet pressure, flow rate, turbidity, permeate residual chlorine concentration, and clear water tank level, with a acquisition frequency of 1-10Hz. The PLC incorporates a machine learning algorithm based on an LSTM time series prediction model, automatically adjusting the dosing dosage (0.5-5 mg / L) and membrane flux (10-30 LMH) according to raw water quality parameters, with a prediction accuracy ≥90%. The remote communication interface supports Modbus, TCP / IP, and other protocols, enabling remote monitoring, data uploading, and remote control of equipment operation.

[0013] Integrated Clear Water Tank: Employing a double-layer anti-corrosion process, the inner wall is sequentially coated with a 50-80μm thick Dacromet coating and a 10-15μm thick ceramic oxide film. The Dacromet coating is a zinc-aluminum-chromium composite coating with a zinc content ≥95% and an adhesion ≥5MPa, providing sacrificial anode protection. The ceramic oxide film is prepared using a micro-arc oxidation process, with AlO₂ as its main component, a porosity ≤2%, and a hardness ≥800HV, forming a physical barrier with salt spray resistance ≥1000 hours, extending the equipment's service life to over 15 years. The clear water tank incorporates a variable frequency water supply pump set and a liquid level control system, employing a PID control algorithm to achieve constant pressure water supply, with a supply pressure of 0.2-0.4MPa and a pressure fluctuation range of ±0.02MPa.

[0014] Module Integration and Connection: The pretreatment module, membrane filtration module, intelligent disinfection module, and central control module are integrated and installed on the top of the integrated clear water tank via a modular bracket, forming a compact, integrated structure. The modules are connected via quick-connect flanges, and EPDM rubber gaskets are used for sealing to ensure no leakage. The modular bracket is welded from Q235 steel with a hot-dip galvanized surface, and has a load-bearing capacity of ≥5000kg, ensuring stable equipment operation.

[0015] Pretreatment process control: Raw water enters from the bottom of sedimentation unit (101) through inlet pipe (104), while polyaluminum chloride (PAC) is added through spiral dosing pipe (102). The central control module (4) automatically adjusts the dosage according to the real-time data of the raw water turbidity sensor: when the turbidity is ≤100 NTU, the dosage is 0.5-2 mg / L; when the turbidity is >100 NTU, the dosage is 2-5 mg / L. The hydraulic retention time of sedimentation unit (101) is 30-60 minutes, which can be automatically adjusted according to the raw water quality. The high-pressure rotary flushing device at the bottom of sedimentation unit (101) regularly flushes the bottom of the unit. The flushing cycle is automatically adjusted according to the sludge deposition thickness, generally once every 4-8 hours, and each flushing time is 3-5 minutes. The sludge generated by flushing is discharged through the drain pipe. The turbidity of the pretreated effluent is controlled at ≤10 NTU and enters the membrane filtration module (2).

[0016] Membrane filtration process control: Pretreated effluent enters the membrane filtration module (2) via a booster pump (8). The main membrane module (201) is running, while the standby membrane module (202) is in standby flushing mode. The central control module (4) monitors the transmembrane pressure difference and running time of the main membrane module (201) in real time. When the transmembrane pressure difference reaches 0.15 MPa or the running time reaches 24 hours, it automatically switches to the standby membrane module (202). During the switching process, the permeate pressure is kept stable by the pressure compensation device (9), and the flow rate fluctuation is ≤5%. The membrane module operating flux is automatically adjusted according to the raw water quality and temperature, and is generally controlled at 10-30 LMH. When the raw water temperature is below 10℃, the membrane flux is automatically reduced by 10-20% to prevent further aggravation of membrane fouling.

[0017] Disinfection process control: Membrane filtration permeate enters the intelligent disinfection module (3), and the chlorine dioxide generator (301) adjusts the dosage of the reagent according to the feedback signal from the residual chlorine online monitoring instrument (302). When the residual chlorine concentration is lower than 0.05 mg / L, the dosage of the reagent is increased; when the residual chlorine concentration is higher than 0.8 mg / L, the dosage of the reagent is reduced to ensure that the residual chlorine concentration is stably maintained within the range of 0.05-0.8 mg / L. The permeate after disinfection is stored in the integrated clear water tank (5).

[0018] Water supply process control: The central control module (4) uses the variable frequency water supply pump group (503) to achieve constant pressure water supply based on the liquid level signal (0.5-3m) fed back by the liquid level control system of the clear water tank (5). When the liquid level is lower than 0.5m, a low liquid level alarm is issued and the water supply is reduced; when the liquid level is higher than 3m, a high liquid level alarm is issued and water production is stopped. The water supply pressure is set to 0.2-0.4MPa, and the PID control algorithm is used to control the pressure fluctuation range within ±0.02MPa to ensure stable water pressure for users. The central control module (4) is the core control unit. It collects the operating parameters of each module in real time through the data acquisition unit (403), including raw water turbidity, pH value, temperature, membrane inlet and outlet pressure, water production flow rate, residual chlorine concentration, clear water tank liquid level, etc., and coordinates the operation of each module to ensure efficient and stable water purification process.

[0019] Membrane cleaning process control: A dynamic cleaning strategy is adopted, automatically adjusting the cleaning cycle and method according to the degree of membrane fouling. Daily online chemical cleaning is performed, with the following procedure: rinsing with 0.1-0.5% citric acid solution for 30 minutes → rinsing with clean water for 15 minutes → rinsing with 0.05-0.2% sodium hypochlorite solution for 30 minutes → rinsing with clean water for 15 minutes. Weekly offline deep cleaning is performed, removing the membrane module from the membrane housing and using a combination of ultrasonic cleaning (frequency 20-40kHz, power 500-1000W) and chemical cleaning. The cleaning cycle is dynamically adjusted according to the membrane fouling rate. When the membrane flux drops to 70% of the initial flux, the cleaning cycle is shortened by 50% to ensure long-term stable operation of the equipment.

Claims

1. An integrated intelligent modular water purification system and its operation control method, characterized in that... include: The pretreatment module (1) includes at least four independent sedimentation units (101), each unit is provided with a spiral drug distribution pipe (102) and a high-pressure rotary flushing device (103) at the bottom, an inlet pipe (104) is provided at the bottom of the unit, and an overflow weir (105) is provided at the top. The membrane filtration module (2) consists of one main membrane group (201) and N spare membrane groups (202) (N≥1). The membrane group adopts a composite membrane element with a molecular weight cutoff of 1000-100000Da. A cleaning water storage tank (203) is set at the bottom, and a pressure sensor (204), a turbidity sensor (205) and an automatic switching valve group (206) are set at the inlet and outlet ends. The intelligent disinfection module (3) includes a chlorine dioxide generator (301), a residual chlorine online monitoring instrument (302), and an automatic dosing unit (303), which are connected in series with the water production pipeline of the membrane filtration module (2); The central control module (4) adopts a PLC control system (401) and integrates a touch screen (402), a data acquisition unit (403) and a remote communication interface (404). The integrated clear water tank (5) has a Dacromet coating (501) (thickness 50-80μm) and a ceramic oxide film layer (502) (thickness 10-15μm) on its inner wall, and is equipped with a variable frequency water supply pump group (503) and a liquid level control system (504). The pretreatment module (1), membrane filtration module (2), intelligent disinfection module (3) and central control module (4) are integrated and installed on the top of the integrated clear water tank (5) through module bracket (6), and the modules are connected by quick-install flange (7).

2. The device according to claim 1, characterized in that: The spiral drug delivery tube (102) is made of 316L stainless steel. The outer wall of the tube has staggered drug delivery holes with a diameter of 3-5mm and a spacing of 15-20mm.

3. The device according to claim 1, characterized in that: The membrane filtration module (2) has a membrane spacing of 8-12cm, the membrane element adopts an external pressure hollow fiber structure, the filtration accuracy is 0.001-0.1μm, and the operating pressure is 0.1-0.6MPa.

4. The device according to claim 1, characterized in that: The cleaning water storage tank (203) is equipped with an ultrasonic cleaning device (207) with a frequency of 20-40kHz, which forms a joint cleaning unit with the chemical cleaning system (208).

5. The device according to claim 1, characterized in that: The central control module (4) has a built-in machine learning algorithm that can automatically adjust the dosage (0.5-5 mg / L) and membrane flux (10-30 LMH) according to the raw water quality parameters (turbidity, COD, temperature).

6. A method for controlling the operation of the equipment according to any one of claims 1-5, characterized in that... Includes the following steps: S1. The raw water is pretreated by module (1), and polyaluminum chloride (PAC) is added through spiral dosing pipe (102). The dosage is automatically adjusted according to the turbidity of the raw water, and the sedimentation time is 30-60 minutes. S2. The pretreated effluent enters the membrane filtration module (2). When the main membrane module (201) is running, the standby membrane module (202) is in standby flushing state. When the transmembrane pressure difference of the main membrane module reaches 0.15MPa, it will automatically switch. S3. The membrane filtration product water passes through the intelligent disinfection module (3), where chlorine dioxide is added until the residual chlorine concentration is 0.05-0.8 mg / L, and then enters the integrated clear water tank (5). S4. The central control module (4) controls the operation of the variable frequency water supply pump group (503) according to the clear water tank level (0.5-3m) to achieve constant pressure water supply of 0.2-0.4MPa; S5. Perform online chemical cleaning once a day and offline deep cleaning once a week. The cleaning cycle is dynamically adjusted according to the membrane fouling rate.

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