A sewage treatment system capable of automatically monitoring the degree of membrane module clogging

Abstract

This invention discloses a wastewater treatment system capable of automatically monitoring the degree of membrane module clogging, comprising an aeration tank, a membrane tank, a collection tank, a lifting device, a membrane module clogging detector, a cleaning unit, and a controller; characterized in that: an aeration device is provided at the bottom of the aeration tank, a plate-shaped membrane module is provided in the membrane tank, a storage plate is provided in the collection tank, and a return pipe is provided in the collection tank, the return pipe being connected to the cleaning unit of the plate-shaped membrane module via a return pump; thus achieving comprehensive cleaning of the membrane module.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, specifically to a wastewater treatment system capable of automatically monitoring the degree of membrane module clogging. Background Technology

[0002] Membrane bioreactors (MBRs) are gaining increasing attention and use due to their advantages such as stable effluent and small footprint. During operation, however, large dissolved organic molecules, particulate matter, and inorganic salts in the mixed liquor gradually adhere to and deposit on the membrane surface, causing a continuous increase in membrane filtration resistance, a significant decrease in membrane flux, and a decline in wastewater treatment efficiency. Membrane fouling is influenced by various factors, including wastewater concentration, dissolved organic matter in the wastewater, the hydrophilicity or hydrophobicity of the membrane material, and the filtration method. To reduce membrane fouling during operation, current technologies employ methods such as modifying the membrane surface to improve its hydrophilicity and anti-fouling properties; blowing large amounts of air into the bottom of the membrane tank using an air compressor to vibrate the membrane fibers and reduce surface fouling; and, if membrane flux drops significantly, often requiring the membrane to be pulled out of the tank and sprayed with large amounts of clean water for cleaning. However, these methods are difficult to monitor the actual degree of membrane fouling, have high energy consumption for decontamination, and require significant labor. Therefore, there is an urgent need to provide a wastewater treatment system that can automatically monitor the degree of membrane module clogging, realize automatic real-time monitoring of membrane fouling, and perform targeted cleaning of fouled parts, thereby further saving manpower, reducing energy consumption, and improving efficiency. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a wastewater treatment system capable of automatically monitoring the degree of membrane module clogging. The system includes an aeration tank, a membrane tank, a collection tank, a lifting device, a membrane module clogging detector, a cleaning unit, and a controller. An aeration device is installed at the bottom of the aeration tank. Plate-shaped membrane modules are installed within the membrane tank. A storage plate is installed within the collection tank, and a return pipe is installed within the collection tank. The return pipe is connected to the cleaning unit of the plate-shaped membrane modules via a return pump. The plate-shaped membrane modules are supported within the membrane tank by membrane frames. The lifting device is connected to the cleaning unit. The membrane module clogging detector is used to detect the degree of clogging of the membrane modules in real time. The controller acquires the membrane module clogging rate, and when the clogging rate exceeds a preset value, the controller activates the cleaning unit. The membrane frame includes a left side plate and a right side plate, with a transverse plate positioned between the left and right sides. The transverse plate is located a certain distance from the bottom of the membrane tank. The plate-shaped membrane modules are mounted on the transverse plate, and slots are provided on the transverse plate corresponding to the placement positions of each plate-shaped membrane. A lifting device is installed on one side of each of the left and right side plates.

[0004] Furthermore, the lifting device includes a lead screw and a slide rod. The lead screw is located on one side of the left side plate, and the slide rod is located on one side of the right side plate. One end of the lead screw is connected to a motor, and a crossbeam is connected between the lead screw and the slide rod. The crossbeam is a hollow water pipe, and multiple cleaning heads are evenly arranged on the crossbeam. The motor can drive the crossbeam to move up and down.

[0005] Furthermore, the membrane module clogging detector includes a laser and a photosensitive sensor. The laser is mounted on the water inlet side of the membrane module via a laser bracket; the photosensitive sensor is mounted on the upper end of the membrane frame at the water outlet end of the membrane module via a sensor bracket. The laser emits a laser beam to the photosensitive sensor, which converts the received light signal into an electrical signal and outputs a current, which is then transmitted to the controller. The clogging rate of the membrane module is calculated using the formula F = 1 - I1 / I2, where F represents the clogging rate of the membrane module, I1 represents the output current of the photosensitive sensor during membrane module use (in amperes), and I2 represents the output current of the photosensitive sensor when the membrane module is not in use (in amperes).

[0006] Furthermore, the cleaning head includes a vibration device, which includes a vibration container. The vibration container includes an upper shell and a lower shell, which are sealed together. The lower shell has a conical structure. A first vibrator and a second vibrator are disposed inside the upper shell, and the first and second vibrators are in contact with each other. The second vibrator is connected to the upper shell through a flange structure. A vibration transmission element is disposed at the bottom end of the second vibrator. The bottom end of the vibration transmission element is connected to an interference fit gear shift lever. The bottom end of the gear shift lever is connected to a working head, and the gear shift lever is connected to a speed adjustment mechanism.

[0007] Furthermore, the speed regulating mechanism includes upper and lower fixed discs and a drive assembly. The drive assembly is connected to the controller. The upper and lower fixed discs are fixed inside the cleaning head via a fixed bracket. The upper and lower fixed discs are fitted inside the gear shift lever. Rotating rings are rotatably connected to the bottom of the upper and lower fixed discs respectively. Multiple loop frames are connected between the two rotating rings. Sliding rods are slidably connected inside the loop frames. One end of the sliding rod is connected to the gear shift lever. Adjusting rods are slidably connected to both ends of the loop frames. One end of the adjusting rod is slidably connected to the loop frame, and the other end of the adjusting rod is connected to the rotating ring. The drive assembly drives the upper rotating ring to rotate clockwise and the lower rotating ring to rotate counterclockwise, thereby adjusting the angle between the loop frame and the horizontal plane.

[0008] Furthermore, the lower side wall of the upper housing is provided with a return water inlet, the top wall of the lower housing is provided with an inclined return water outlet channel, and the lower end of the side wall of the lower housing opposite to the return water channel is provided with a gas channel; the gas and return water are mixed and sprayed out within the space enclosed by the lower housing and the gear shift lever.

[0009] Furthermore, the cross-section of the vibration transmission component is a T-shaped structure, and the vibration transmission component includes a transverse wing plate and a longitudinal web plate, which are formed together; the return water enters from the return water inlet and flows into the space enclosed by the transverse wing plate, the longitudinal web plate, the lower part of the upper shell, and the upper part of the lower shell.

[0010] Furthermore, the intensity of the laser beam emitted by the laser (14) can also be adjusted. The laser (14) can be selectively connected to resistors with different resistance values. The intensity of the laser beam can be adjusted by selecting and connecting resistors with different resistance values.

[0011] Compared with the prior art, the beneficial effects of the present invention are:

[0012] 1) By using a simple combination of laser and photosensitive sensor, the laser's high beam-forming properties, its resistance to divergence, and its resistance to interference from natural light are utilized to detect the degree of contamination in membrane modules. This method has the advantages of low cost and good detection effect.

[0013] 2) The cleaning unit of the membrane module is set to be liftable, so as to achieve all-round cleaning of the membrane module without having to pull the membrane module out of the membrane tank for cleaning, saving time and effort;

[0014] 3) The cleaning head of the cleaning unit uses the principle of vibration to fully mix the cleaning liquid and gas, thereby improving the cleaning effect during the cleaning process. At the same time, the vibration speed of the working head can be adjusted by means of an interference fit gear lever at the bottom of the vibration transmission component in the vibration mechanism. The gear lever is connected to a speed adjustment mechanism to adapt to different cleaning needs. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the membrane module structure inside the membrane tank of the present invention;

[0016] Figure 2 This is a schematic diagram of the membrane module clogging detector structure of the present invention;

[0017] Figure 3 This is a schematic diagram of the cleaning unit of the present invention;

[0018] Figure 4 This is a schematic diagram of the overall structure of the cleaning unit of the present invention;

[0019] Figure 5This is a schematic diagram of the speed regulating mechanism of the present invention;

[0020] Figure 6 This is a partial structural schematic diagram of the speed regulating mechanism of the present invention.

[0021] Icons: 1-Membrane tank; 2-Plate membrane module; 3-Cleaning unit; 4-Membrane module clogging detector; 5-Left side plate; 6-Right side plate; 7-Horizontal plate; 8-Screw; 9-Slide bar; 10-Motor; 11-Hollow water pipe; 12-Cleaning head; 13-Photosensitive sensor; 14-Laser; 15-Sensor bracket; 16-Laser bracket; 17-Upper housing; 18-Lower housing; 19-First vibrator; 20-Second vibrator; 21-Vibration source; 22-Speed ​​shift lever; 23-Return water inlet; 24-Return water outlet channel; 25-Gas channel; 26-Vibration transmission component; 27-Rotating ring; 28-U-shaped frame; 29-Adjusting rod; 30-Slide bar. Detailed Implementation

[0022] To more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Please see Figure 1 This invention provides a wastewater treatment system capable of automatically monitoring the degree of membrane module clogging. It includes an aeration tank, a membrane tank 1, a collection tank, a lifting device, a membrane module clogging detector, a cleaning unit, and a controller. The lifting device, membrane module clogging detector, and cleaning unit are all connected to the controller. An aeration device is installed at the bottom of the aeration tank to pre-aerate the wastewater before it enters the membrane tank 1. The aerated wastewater is pumped into the membrane tank 1, where a plate-shaped membrane module 2 is installed. The plate-shaped membrane module 2 filters the wastewater, and the filtered water is pumped into the collection tank for storage. To improve the cleanliness of the water stored in the collection tank, a storage plate is installed at the top of the collection tank to accumulate any remaining pollutants in the treated water.

[0024] However, as the usage time of membrane module 2 increases, pollutants will continuously accumulate on the surface of the membrane module, gradually clogging the membrane surface and causing the filtration function of membrane module 2 to decline continuously. In order to ensure the treatment effect of membrane module 2, the degree of fouling of membrane module 2 must be monitored in real time. When the degree of fouling of membrane module 2 reaches a certain value, the membrane flux will be greatly reduced, which will seriously affect the efficiency of membrane module in treating water, and cleaning treatment of membrane module must be considered. In order to save cleaning water and prevent the generation of new polluted water, a return pipe is installed in the water collection tank. The return pipe is connected to the plate membrane module cleaning unit 3 through a return pump to provide cleaning water for cleaning membrane module.

[0025] The plate-shaped membrane module 2 is supported in the membrane tank 1 by a membrane frame. The lifting device is connected to the cleaning unit 3. The membrane module clogging detector 4 is used to detect the degree of clogging of the membrane module 2 in real time. The controller obtains the membrane module clogging rate. When the clogging rate exceeds a preset value, the controller controls the start of the cleaning unit 3. Due to the setting of the lifting device, the controller controls the lifting speed of the cleaning unit, so that the cleaning unit can achieve all-round and no dead angle cleaning of the membrane module, which solves the problem of pulling the membrane module out of the membrane tank when cleaning the membrane module in the prior art, which is time-consuming and labor-intensive.

[0026] The membrane frame includes a left side plate 5 and a right side plate 6. A transverse plate 7 is disposed between the left side plate 5 and the right side plate 6. To maintain the cleanliness of the membrane assembly, the transverse plate 7 is positioned at a certain distance from the bottom of the membrane tank. The plate-shaped membrane assembly 2 is disposed on the transverse plate 7, and slots are provided on the transverse plate 7 corresponding to the placement positions of each plate-shaped membrane. A lifting device is disposed on one side of the left side plate 5 and the right side plate 6. The lifting device includes a lead screw 8 and a slide bar 9. The lead screw 8 is disposed on one side of the left side plate 5, and the slide bar 9 is disposed on one side of the right side plate 6. One end of the lead screw 8 is connected to a motor 10. A crossbeam is connected between the lead screw 8 and the slide bar 9. The crossbeam is a hollow water pipe 11, and multiple cleaning heads 12 are evenly disposed on the crossbeam. The controller can control the rotation of the motor as needed, and the motor 10 can drive the crossbeam to move up and down at a certain frequency.

[0027] See Figure 2 , Figure 2A schematic diagram of the membrane module clogging detector structure is shown. The membrane module clogging detector 4 includes a laser 14 and a photosensitive sensor 13. The laser 14 is installed on the water inlet side of the membrane module via a laser bracket 16, that is, on the opposite side of the water outlet side after filtration by the membrane module. The photosensitive sensor 13 is installed on the upper end of the membrane frame at the water outlet end of the membrane module via a sensor bracket 15, that is, on the water outlet side after filtration by the membrane module. The laser 14 emits a laser beam to the photosensitive sensor 13. After the laser beam passes through the membrane module 2, the photosensitive sensor 13 receives the light signal of the laser beam and converts the light signal into an electrical signal, outputting a current of a certain intensity. The current value is transmitted to the controller, and the controller calculates the degree of clogging of the membrane module based on the current value.

[0028] The formula for calculating the clogging rate of the membrane module 2 is F=1-I1 / I2, where F represents the clogging rate of the membrane module, I1 represents the output current of the photosensitive sensor during the use of the membrane module (in amperes), and I2 represents the output current of the photosensitive sensor when the membrane module is not in use (in amperes).

[0029] In addition, the intensity of the laser beam emitted by the laser 14 can be adjusted as needed. Specifically, the laser 14 can be connected to resistors with different resistance values. By selecting and connecting resistors with different resistance values, the light intensity of the laser beam can be adjusted to meet different needs.

[0030] Generally, in the initial stage of membrane module use, due to the high cleanliness of the membrane surface and high membrane flux, the clogging rate of the membrane module is obviously very low. Therefore, the membrane module clogging detector 4 frequently detects the degree of clogging in the initial stage, which to some extent wastes the power of the membrane module clogging detector 4. Therefore, in order to reduce power consumption, the membrane module clogging detector 4 is set to a static mode and a dynamic mode. In the initial stage of use of the membrane module, the controller can adjust the membrane module clogging detector 4 to the static mode. The controller can activate the membrane module clogging detector 4 at any time, that is, adjust it to the dynamic mode. The controller dynamically adjusts the static mode and the dynamic mode according to the magnitude of the received current value.

[0031] When the controller detects a membrane module clogging rate exceeding a preset value via membrane module clogging detector 4, it activates the cleaning unit; the specific structure of each cleaning head 12 in the cleaning unit is as follows, refer to Figure 3-6The cleaning head 12 includes a vibration device, which includes a vibration container. The vibration container includes an upper shell 17 and a lower shell 18, which are sealed together. The lower shell 18 has a conical structure. A first vibrator 19 and a second vibrator 20 are disposed inside the upper shell 17. The first vibrator 19 and the second vibrator 20 are in contact with each other. The first vibrator 19 is connected to a vibration source 21. The second vibrator 20 is connected to the upper shell through a flange structure. A vibration transmission element 26 is disposed at the bottom end of the second vibrator 20. The bottom end of the vibration transmission element 26 is connected to an interference fit gear shift lever 22. The bottom end of the gear shift lever 22 is connected to a working head and a speed adjustment mechanism.

[0032] The speed regulating mechanism includes upper and lower fixed discs and a drive assembly. The drive assembly is connected to the controller. The upper and lower fixed discs are fixed inside the cleaning head via a fixed bracket. The upper and lower fixed discs are fitted inside the gear shift lever 22. Rotating rings 27 are rotatably connected to the bottom of the upper and lower fixed discs respectively. Multiple loop frames 28 are connected between the two rotating rings 27. A sliding rod 30 is slidably connected inside the loop frame 28. One end of the sliding rod 30 is connected to the gear shift lever 22. Adjusting rods 29 are slidably connected to both ends of the loop frame 28. One end of the adjusting rod 29 is slidably connected to the loop frame 28, and the other end of the adjusting rod 29 is connected to the rotating ring 27. The drive assembly drives the upper rotating ring to rotate clockwise and the lower rotating ring to rotate counterclockwise, thereby adjusting the angle between the loop frame 28 and the horizontal plane, and thus adjusting the vibration speed of the working head.

[0033] The lower side wall of the upper housing 17 is provided with a return water inlet 23, and the top wall of the lower housing 18 is provided with a return water outlet channel 24. The return water generates foam during continuous swirling. A gas channel 25 is provided at the lower end of the side wall of the lower housing 18 opposite to the return water outlet channel 24. The gas channel 25 is connected to a gas source, and the gas and return water are mixed and sprayed out in the space enclosed by the lower housing (18) and the gear shift lever (22).

[0034] The vibration transmission component 26 has a T-shaped cross-section and includes a transverse wing plate and a longitudinal web plate, which are formed together. The return water enters from the return water inlet 23 and flows into the space enclosed by the transverse wing plate, the longitudinal web plate, the lower part of the upper shell 17, and the upper part of the lower shell 18.

[0035] The controller compares the real-time clogging rate of membrane module 2 with the clogging threshold of the membrane module stored in the controller to determine whether to start the cleaning unit and further determine whether to start the motor rotation. The controller can adjust the angle of the drive component to drive the upper rotating ring to rotate clockwise and the lower rotating ring to rotate counterclockwise according to the degree of clogging of the membrane module, so as to adjust the required angle between the ring 28 and the horizontal plane, obtain different vibration speeds, and thus achieve the required cleaning effect.

[0036] The specific usage process is as follows: Before the sewage enters the membrane tank 1, it is first aerated by an aeration device installed at the bottom of the aeration tank; then, the aerated sewage is pumped into the membrane tank 1, where a plate-shaped membrane module 2 is installed. The sewage is filtered by the plate-shaped membrane module 2, and the filtered water is pumped into a collection tank for storage. During the sewage filtration process, the membrane module clogging detector 4 detects the degree of clogging of the membrane module 2 in real time. The laser 14 of the membrane module clogging detector 4 emits a laser signal to the membrane module, while the photosensitive sensor 13 located on the other side of the membrane module continuously receives the laser signal. As the membrane module is used for a longer period of time, pollutants will continuously accumulate on the surface of the membrane module, thereby causing the photosensitive sensor 13 to receive the laser signal. The received light signal also changes accordingly. The photosensitive sensor 13 receives the light signal from the laser beam and converts it into an electrical signal, outputting current and transmitting the current value to the controller. The controller calculates based on the current value to reflect the degree of blockage of the membrane module. Based on the degree of blockage of the membrane module, the controller controls the lifting device to lift and lower, driving the cleaning unit 3 to lift and lower. At the same time, it controls the drive component to adjust the angle between the rotating frame 28 and the horizontal plane to obtain the required vibration speed. The vibration source 21 drives the first vibrator 19 and the second vibrator 20 to vibrate. At the same time, the vibration force is transmitted to the working head through the vibration transmission component 26, realizing the full mixing of the return water through the return water inlet 23 and the gas entering through the gas channel 25. The cleaning water is sprayed out from the cleaning head 12 to achieve vibration cleaning of the membrane module.

[0037] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A sewage treatment system capable of automatically monitoring the degree of membrane module clogging, comprising an aeration tank, a membrane tank, a water collecting tank, a lifting device, a membrane module clogging degree detector, a cleaning unit and a controller; characterized in that: The aeration tank bottom is provided with an aeration device, the membrane tank is provided with a plate-shaped membrane assembly, the water collecting tank is provided with an accumulation plate, the water collecting tank is provided with a reflux pipe, the reflux pipe is connected with the cleaning unit of the plate-shaped membrane assembly through a reflux pump; the plate-shaped membrane assembly is supported in the membrane tank through a membrane frame, the lifting device is connected with the cleaning unit, the membrane assembly blockage detector is used for real-time detection of the blockage degree of the membrane assembly; the controller acquires the membrane assembly blockage rate, when the blockage rate exceeds a preset value, the controller controls the start of the cleaning unit; the membrane frame comprises a left side plate and a right side plate, a transverse plate is arranged between the left side plate and the right side plate, and the transverse plate is a certain distance away from the bottom of the membrane tank; the plate-shaped membrane assembly is arranged on the transverse plate, and a slot hole is arranged on the transverse plate at a position corresponding to each plate-shaped membrane; the left side plate and the right side plate are provided with a lifting device on one side; the membrane assembly blockage detector comprises a static mode and a dynamic mode; the lifting device comprises a lead screw and a slide rod, the lead screw is arranged on one side of the left side plate, the slide rod is arranged on one side of the right side plate, one end of the lead screw is connected with a motor, a cross beam is arranged between the lead screw and the slide rod, the cross beam is a hollow water pipe, and a plurality of cleaning heads are uniformly arranged on the cross beam; the motor can drive the cross beam to move up and down; The cleaning head comprises a vibration device, the vibration device comprises a vibration container, the vibration container comprises an upper shell and a lower shell, the upper shell is internally provided with a first vibrator and a second vibrator, the bottom end of the second vibrator is provided with a vibration transmission member, the bottom end of the vibration transmission member is connected with a variable speed rod through interference fit, and the variable speed rod is connected with a speed regulation mechanism; the speed regulation mechanism comprises upper and lower fixed discs and a driving assembly, the driving assembly is connected with the controller, the upper and lower fixed discs are fixed in the internal space of the cleaning head through a fixed support, the upper and lower fixed discs are sleeved on the variable speed rod, the bottom of the upper and lower fixed discs is respectively rotationally connected with a rotating ring, a plurality of back-shaped frames are connected between the two rotating rings, a slide rod is slidably connected in the back-shaped frame, one end of the slide rod is connected with the variable speed rod, the two ends of the back-shaped frame are slidably connected with adjusting rods, one end of the adjusting rod is slidably connected with the back-shaped frame, the other end of the adjusting rod is connected with the rotating ring, the driving assembly drives the upper rotating ring to rotate clockwise and the lower rotating ring to rotate counterclockwise, so that the included angle between the back-shaped frame and the horizontal plane is adjusted; a reflux water inlet is arranged on the lower side wall of the upper shell, a reflux water outlet channel is arranged on the top wall of the lower shell in a slope manner, and a gas channel is arranged on the lower end of the side wall of the lower shell on the side opposite to the reflux water channel.

2. The sewage treatment system capable of automatically monitoring the degree of membrane module blockage according to claim 1, characterized in that: The membrane module blockage degree detector comprises a laser and a photosensitive sensor, the laser is installed on the water inlet side of the membrane module through a laser support; the photosensitive sensor is installed on the upper end of the membrane frame at the water outlet end of the membrane module through a sensor support, the laser emits a laser beam to the photosensitive sensor, the photosensitive sensor converts the received light signal into an electric signal and outputs an electric current, the current value is transmitted to the controller, and the blockage rate calculation formula of the membrane module is F=1-I1 / I2, wherein F represents the blockage rate of the membrane module, I1 represents the output current of the photosensitive sensor during use of the membrane module, the unit is ampere, and I2 represents the output current of the photosensitive sensor when the membrane module is not used, the unit is ampere.

3. The sewage treatment system capable of automatically monitoring the degree of membrane module blockage according to claim 2, characterized in that: The upper shell and the lower shell are sealingly connected; the lower shell is a conical structure, and the first vibrator and the second vibrator are arranged in contact with each other; the second vibrator is connected with the upper shell through a flange structure, and the bottom end of the variable speed rod is connected with a working head.

4. The sewage treatment system capable of automatically monitoring the degree of membrane module blockage according to claim 3, characterized in that: The gas and the backflow water are mixed and sprayed in the space surrounded by the lower shell and the variable speed rod.

5. The sewage treatment system capable of automatically monitoring the degree of membrane module blockage according to claim 4, characterized in that: The vibration transmission member is a T-shaped structure, and comprises a transverse wing plate and a longitudinal web plate which are formed together; the backflow water enters from the backflow water inlet and flows into the space surrounded by the transverse wing plate, the longitudinal web plate, the lower part of the upper shell and the upper part of the lower shell.

6. The sewage treatment system capable of automatically monitoring the degree of membrane module blockage according to claim 5, characterized in that: The intensity of the laser beam emitted by the laser can also be adjusted, and the laser is selectively connected with resistors with different resistance values, and the light intensity of the laser beam is adjusted by selecting resistors with different resistance values to be connected.

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