Modular wastewater treatment device based on MABR and treatment method

Abstract

The present application relates to sewage treatment technical field, specifically disclose a kind of modularization sewage treatment device and processing method based on MABR, comprising: mounting bracket and hollow fiber membrane being arranged on mounting bracket, air inlet pipe and air outlet pipe are arranged on mounting bracket, exhaust pipe is arranged in hollow fiber membrane, the upper end of hollow fiber membrane is communicated with air inlet pipe, lower end is closed;The upper end of exhaust pipe is communicated with air outlet pipe, gas in hollow fiber membrane is discharged from air outlet pipe by exhaust pipe;Cleaning mechanism includes flexible filter screen cylinder being sleeved on hollow fiber membrane and lifting assembly for making flexible filter screen cylinder lift along vertical direction, flexible filter screen cylinder is made of flexible material, and water and oxygen can pass through flexible filter screen cylinder, the inner circumferential wall of flexible filter screen cylinder is attached with the outer circumferential wall of hollow fiber membrane, and hollow fiber membrane is completely located in flexible filter screen cylinder;The beneficial effects of the present application can clean the hollow fiber membrane surface inside hollow fiber membrane.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, specifically to a modular wastewater treatment device and treatment method based on MABR. Background Technology

[0002] Membrane aerated bioreactor (MABR) is an innovative wastewater treatment technology. Its core lies in the use of a special permeable membrane as its main component. This membrane simultaneously acts as a biofilm carrier and a bubble-free aeration medium. In traditional wastewater treatment, aeration requires a large amount of energy to blow oxygen into the water. MABR technology, however, directly diffuses oxygen to the biofilm attached to its surface through a hollow fiber membrane, achieving "bubble-free aeration." This principle results in extremely high oxygen mass transfer efficiency, reducing energy consumption by up to 75% or more compared to the traditional activated sludge process. Its main advantage lies in enabling simultaneous and efficient nitrification and denitrification reactions within a single reactor. In other words, under aerobic conditions, aerobic microorganisms on the outer layer of the biofilm convert ammonia nitrogen into nitrate nitrogen, while the area near the membrane wall and the inner layer of the biofilm becomes an anaerobic microenvironment due to the rapid consumption of oxygen. This facilitates denitrifying bacteria to reduce nitrate nitrogen back to nitrogen gas for discharge, thus achieving efficient nitrogen removal. In addition, MABR technology is very suitable for modular design and application due to its compact structure, low sludge production, and simple operation and maintenance. These standardized MABR modules can be flexibly assembled according to the treatment scale, which greatly simplifies the engineering implementation and provides an efficient, energy-saving, and space-saving advanced solution for decentralized wastewater treatment and upgrading in urban areas, communities, industrial parks, and other scenarios.

[0003] Chinese patent document CN220907287U discloses a MABR membrane module, including an inlet pipe, a gas distributor, an inlet control valve unit, a first gas collector, a hollow fiber membrane element, a second gas collector, a gas concentrator, an outlet control valve unit, and an outlet pipe. Multiple sets of hollow fiber membrane elements are connected between the gas distributor and the gas concentrator. The gas distributor is connected to the inlet pipe, and the gas concentrator is connected to the outlet pipe. Each set of hollow fiber membrane elements has a first gas collector and a second gas collector connected to both ends. Each first gas collector is connected to the gas distributor through an inlet control valve unit, and each second gas collector is connected to the gas concentrator through an outlet control valve unit.

[0004] During long-term operation, hollow fiber membranes will accumulate sludge due to biofilm aging and shedding, as well as suspended particles. Some of this sludge will settle, while the rest will accumulate on the membrane surface to form a hard scale layer. Because the hollow fiber membranes are closely arranged and the distance between them is small, the existing technology of directly cleaning with water or brushes is not easy to clean the surface of the hollow fiber membrane inside the membrane, resulting in low cleaning efficiency. Summary of the Invention

[0005] This invention provides a modular wastewater treatment device and method based on MABR, aiming to solve the problem in related technologies that it is not easy to clean the surface of the hollow fiber membrane inside the hollow fiber membrane, resulting in low cleaning efficiency.

[0006] A modular wastewater treatment device based on MABR includes a mounting frame and a hollow fiber membrane mounted on the mounting frame. The mounting frame is equipped with an air inlet pipe and an air outlet pipe. The device also includes:

[0007] The exhaust pipe is installed inside the hollow fiber membrane. The upper end of the hollow fiber membrane is connected to the air inlet pipe and the lower end is closed. The upper end of the exhaust pipe is connected to the air outlet pipe. The gas inside the hollow fiber membrane is discharged from the air outlet pipe through the exhaust pipe.

[0008] The cleaning mechanism includes a flexible filter cylinder fitted onto a hollow fiber membrane and a lifting assembly for raising and lowering the flexible filter cylinder in a vertical direction. The inner circumferential wall of the flexible filter cylinder is in contact with the outer circumferential wall of the hollow fiber membrane, and the hollow fiber membrane is completely located inside the flexible filter cylinder.

[0009] During the filtration process of hollow fiber membranes, the protective flexible filter cartridge structure on its outer side significantly reduces the accumulation of aging biofilm and hard scale directly adhering to the surface of the hollow fiber membrane. Due to the presence of the flexible filter cartridge, most of the aging biofilm and hard scale preferentially adhere to the outer surface of the flexible filter cartridge rather than directly to the hollow fiber membrane. This reduces the degree of contamination on the hollow fiber membrane surface, making cleaning and maintenance easier and more efficient. When cleaning is required, the flexible filter cartridge can be moved using the lifting assembly. As the hollow fiber membrane moves downwards, the aging biofilm and hard scale layer attached to the outside of the flexible filter cylinder are also moved along with it, thus achieving initial cleaning of the hollow fiber membrane surface. When the flexible filter cylinder completely detaches from below the hollow fiber membrane and moves to the connecting rod, most of the aging biofilm and hard scale layer have been successfully removed from the surface of the hollow fiber membrane and concentrated at the lower end of the hollow fiber membrane. This cleaning method not only improves cleaning efficiency but also reduces potential damage to the hollow fiber membrane during the cleaning process, extending the service life of the hollow fiber membrane.

[0010] Preferably, the hollow fiber membrane is provided with multiple hollow fiber membranes, and each hollow fiber membrane surface is covered with a flexible filter cylinder.

[0011] Preferably, the lifting assembly includes a connecting plate that is slidably mounted on the mounting frame in a vertical direction and a driving component for driving the connecting plate to lift. The upper end of the flexible filter cylinder is fixedly connected to the connecting plate.

[0012] Preferably, the driving component includes a lead screw rotatably mounted on the mounting bracket and a motor fixedly mounted on the mounting bracket. The output end of the motor is connected to the lead screw, which passes through a connecting plate and is threadedly engaged with the connecting plate. A slide rod is provided on the mounting bracket and passes through the connecting plate.

[0013] Preferably, the upper end of the flexible filter cylinder is provided with a cleaning ring, and the cleaning ring is sleeved on the hollow fiber membrane. A brush is provided on the inner circumferential wall of the cleaning ring, and the end of the brush facing the hollow fiber membrane abuts against the hollow fiber membrane.

[0014] One end of the brush faces the hollow fiber membrane and is in close contact with its outer surface. As the upper end of the flexible filter cartridge moves up and down relative to the hollow fiber membrane, the cleaning ring rotates clockwise and counterclockwise. This movement allows the brush on the cleaning ring to effectively and thoroughly clean the outer surface of the hollow fiber membrane. Because the outer surface of the hollow fiber membrane is wrapped by the flexible filter cartridge, and the inner surface of the flexible filter cartridge is in close contact with the outer surface of the hollow fiber membrane, the aging biofilm and hard scale layer adhering to the outer surface of the hollow fiber membrane are relatively thin. In this case, the cleaning work can be completed smoothly without applying excessive cleaning force, thus avoiding the risk of damage to the outer surface of the hollow fiber membrane caused by a thicker layer of aging biofilm and hard scale. This not only improves cleaning efficiency but also extends the service life of the hollow fiber membrane.

[0015] Preferably, a first gear is sleeved on the cleaning ring, and two adjacent first gears mesh with each other. A second gear is installed on the connecting plate. The second gear slides vertically and is sleeved on the lead screw. The second gear meshes with one of the first gears.

[0016] By setting up gear one and gear two, the rotation of the lead screw can drive gear two to rotate, thereby causing gear one to drive the cleaning ring to rotate, thus completing the cleaning of the outer surface of the hollow fiber membrane.

[0017] Preferably, a base plate is slidably mounted on the mounting frame in the vertical direction, the bottom end of the flexible filter cylinder is fixedly mounted on the base plate, and both the slide rod and the lead screw pass through the base plate. The lead screw and the base plate are threadedly engaged, and a limit member is provided on the slide rod to limit the base plate after the connecting plate and the base plate descend together by a certain distance.

[0018] Preferably, the limiting component includes an annular platform disposed at the bottom end of the slide rod, and a smooth section is provided at the lower end of the lead screw. When the base plate moves to the smooth section of the lead screw, it abuts against the annular platform. As the lead screw rotates, the connecting plate continues to descend and deforms the flexible filter cylinder.

[0019] When the base plate moves to the smooth section of the lead screw, it will come into contact with and abut against the ring platform. The ring platform acts as a barrier to prevent the base plate from moving further downward.

[0020] Preferably, the mounting frame has multiple water spray nozzles (first type) for spraying water onto the hollow fiber membrane from the top end downwards, and the base plate has multiple water spray nozzles (second type) for spraying water onto the flexible filter cylinder above.

[0021] When the brush on the cleaning ring cleans the hollow fiber membrane, the water jet from nozzle one washes away the aged biofilm and hard scale that the brush removes. As the flexible filter cartridge repeatedly transitions between loosening and straightening, nozzle two sprays water onto the aged biofilm and hard scale adhering to the outer surface of the flexible filter cartridge, making it easier for these substances to detach.

[0022] On the other hand, the present invention also provides a wastewater treatment method, wherein the wastewater treatment method utilizes the modular wastewater treatment device based on MABR as described in any of the above preferred technical solutions, and the wastewater treatment method includes the following steps:

[0023] S1. First, the hollow fiber membrane is placed in the sewage tank. Then, air is sent into the air inlet pipe on the mounting frame. Oxygen enters the hollow fiber membrane through the air inlet pipe. The oxygen inside the hollow fiber membrane passes through the hollow fiber membrane and enters the aerobic zone on the surface of the hollow fiber membrane to provide oxygen for the bacteria.

[0024] S2. After the hollow fiber membrane has been working for a period of time, remove the mounting frame and hollow fiber membrane from the sewage tank, and then start the motor to lower the connecting plate and the bottom plate.

[0025] S3. After the base plate is limited by the ring platform, the lead screw continues to rotate to lower the connecting plate. When the connecting plate moves to the smooth section of the lead screw, the motor reverses to raise the connecting plate a certain distance. Then the motor rotates forward again to lower the connecting plate, thereby deforming the flexible filter screen and shaking off the dirt.

[0026] S4. After cleaning, reset the flexible filter screen, and finally put the mounting bracket and hollow fiber membrane into the sewage tank.

[0027] When the hollow fiber membrane is in operation, due to the flexible filter cylinder on the outside, most of the aged biofilm and hard scale adhere to the outer surface of the flexible filter cylinder. This prevents the outer surface of the hollow fiber membrane from being contaminated with a thick layer of aged biofilm and hard scale, thus reducing the difficulty of cleaning the hollow fiber membrane. During the cleaning process, the lifting component first drives the flexible filter cylinder to move downward relative to the hollow fiber membrane. In this way, the flexible filter cylinder can carry the aged biofilm and hard scale on the outside of the hollow fiber membrane downward together. When the flexible filter cylinder detaches from the lower end of the hollow fiber membrane and moves to the connecting rod, most of the aged biofilm and hard scale have been cleaned to the lower end of the hollow fiber membrane. One end of the brush faces the hollow fiber membrane and contacts the outer surface of the hollow fiber membrane. When the upper end of the flexible filter cylinder moves up and down relative to the hollow fiber membrane, the cleaning ring rotates clockwise and counterclockwise, causing the brush on the cleaning ring to clean the outer surface of the hollow fiber membrane. Because the outer surface of the hollow fiber membrane is covered by the flexible filter cylinder, and the inner surface of the flexible filter cylinder is in contact with the outer surface of the hollow fiber membrane, the aging biofilm and hard scale layer attached to the outer surface of the hollow fiber membrane are relatively thin. It is not necessary to use too much cleaning force to complete the cleaning, thus avoiding the situation where a thicker layer of aging biofilm and hard scale layer is attached to the outer surface of the hollow fiber membrane, which would require greater cleaning force and thus damage the outer surface of the hollow fiber membrane.

[0028] By adopting the above technical solution, the beneficial effects of the present invention are as follows:

[0029] 1. When the hollow fiber membrane is in operation, because a flexible filter cylinder is installed on the outside, most of the aged biofilm and hard scale adhere to the outer surface of the flexible filter cylinder. This avoids the outer surface of the hollow fiber membrane from being contaminated with a thick layer of aged biofilm and hard scale, thus reducing the difficulty of cleaning the hollow fiber membrane. During cleaning, the lifting component first moves the flexible filter cylinder downward relative to the hollow fiber membrane. In this way, the flexible filter cylinder can move the aged biofilm and hard scale on the outside of the hollow fiber membrane downward together. When the flexible filter cylinder detaches from the lower end of the hollow fiber membrane and moves to the connecting rod, most of the aged biofilm and hard scale have been cleaned to the lower end of the hollow fiber membrane.

[0030] 2. One end of the brush faces the hollow fiber membrane and abuts against its outer surface. As the upper end of the flexible filter cylinder moves up and down relative to the hollow fiber membrane, the cleaning ring rotates clockwise and counterclockwise, causing the brush on the cleaning ring to clean the outer surface of the hollow fiber membrane. Because the flexible filter cylinder covers the outer surface of the hollow fiber membrane, and the inner surface of the flexible filter cylinder is in contact with the outer surface of the hollow fiber membrane, the aging biofilm and hard scale layer attached to the outer surface of the hollow fiber membrane are relatively thin. Therefore, cleaning can be completed without excessive cleaning force, avoiding the situation where a thicker layer of aging biofilm and hard scale layer requires greater cleaning force, thus preventing damage to the outer surface of the hollow fiber membrane. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0032] Figure 2 This is a cross-sectional view of the hollow fiber membrane of the present invention.

[0033] Figure 3 for Figure 2 Enlarged view of point A in the middle.

[0034] Figure 4 for Figure 2 Enlarged view of point B in the middle.

[0035] Figure 5 for Figure 2 A magnified view of point C in the middle.

[0036] Figure 6 This is a top view of the connecting plate of the present invention.

[0037] Figure 7 This is a schematic diagram of the mounting bracket of the present invention.

[0038] Figure 8 This is a cross-sectional view of the hollow fiber membrane of the present invention.

[0039] Figure label:

[0040] 1. Mounting bracket; 11. Air inlet pipe; 12. Air outlet pipe; 13. Slide rod; 14. Ring platform; 15. Water inlet pipe one; 16. Spray nozzle one; 2. Hollow fiber membrane; 3. Exhaust pipe; 4. Cleaning mechanism; 41. Filter screen cylinder; 42. Cleaning assembly; 421. Cleaning ring; 422. Gear one; 423. Gear two; 424. Gear three; 425. Gear four; 426. Slider; 43. Lifting assembly; 431. Connecting plate; 432. Base plate; 433. Lead screw; 434. Motor; 44. Water inlet pipe two; 45. Spray nozzle two. Detailed Implementation

[0041] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0042] like Figures 1-2 As shown, an embodiment of the present invention provides a modular wastewater treatment device based on MABR, including a mounting frame 1, multiple hollow fiber membranes 2, multiple vent pipes 3, and a cleaning mechanism 4. The hollow fiber membranes 2 are mounted on the mounting frame 1, and the vent pipes 3 are inserted inside the hollow fiber membranes 2 to discharge the air inside the hollow fiber membranes 2. The cleaning mechanism 4 is mounted on the mounting frame 1 and is used to clean the aging biofilm and hard scale layer on the outer surface of the hollow fiber membranes 2.

[0043] During operation, air is first introduced into the hollow fiber membrane 2. After entering the hollow fiber membrane 2, the oxygen in the air passes through the hollow fiber membrane 2 and enters the sewage, providing oxygen for the bacteria. The remaining air inside the hollow fiber membrane 2 enters the exhaust pipe 3 and is then discharged to the outside. After the hollow fiber membrane 2 has been working for a period of time, when the biofilm on its outer side ages or forms a hard scale layer, the mounting frame 1 is lifted out of the sewage tank. Then, the aging biofilm and hard scale layer on the surface of the hollow fiber membrane 2 are cleaned by the cleaning mechanism 4. After cleaning, the mounting frame 1 and the hollow fiber membrane 2 are put back into the sewage tank to continue working.

[0044] like Figures 1-5 As shown, the mounting frame 1 is equipped with an air inlet pipe 11 and an air outlet pipe 12. A fan (not shown in the figure) connected to the air inlet pipe 11 is installed on the outside of the mounting frame 1. The fan is used to send air into the air inlet pipe 11. The upper end of the hollow fiber membrane 2 is connected to the air inlet pipe 11, and the lower end is closed. The upper end of the exhaust pipe 3 is connected to the air outlet pipe 12. The lower end of the exhaust pipe 3 is close to the bottom of the inner side of the hollow fiber membrane 2. Air enters the hollow fiber membrane 2 through the air inlet pipe 11, and then flows downward from the upper end of the hollow fiber membrane 2 until it reaches the bottom of the hollow fiber membrane 2. Then it enters the exhaust pipe 3 from the lower end of the exhaust pipe 3, and finally is discharged to the outside from the air outlet pipe 12.

[0045] like Figures 1-5 and Figure 8 As shown, the cleaning mechanism 4 includes multiple flexible filter cylinders 41, a cleaning assembly 42, and a lifting assembly 43. The multiple flexible filter cylinders 41 are respectively fitted onto multiple hollow fiber membranes 2. The flexible filter cylinders 41 are made of flexible material, and both water and oxygen can pass through the flexible filter cylinders 41. The inner circumferential wall of the flexible filter cylinder 41 is in contact with the outer circumferential wall of the hollow fiber membrane 2. A solid connecting rod extends downward from the lower end of the hollow fiber membrane 2. The lifting assembly 43 is used to move the flexible filter cylinder 41 downward relative to the hollow fiber membrane 2 until it moves to the connecting rod after it is disengaged from the lower end of the hollow fiber membrane 2. A hollow tube extends upward from the upper end of the hollow fiber membrane 2. The upper end of the hollow tube is fixed to the mounting frame 1. When the hollow fiber membrane 2 is working normally, the hollow fiber membrane 2 is completely located inside the flexible filter cylinder 41. The cleaning assembly 42 is used to clean the outer surface of the hollow fiber membrane 2 during the lifting and lowering process of the flexible filter cylinder 41 relative to the hollow fiber membrane 2.

[0046] When the hollow fiber membrane 2 is in operation, since a flexible filter cylinder 41 is sleeved on the outside of the hollow fiber membrane 2, most of the aged biofilm and hard scale layer are attached to the outer surface of the flexible filter cylinder 41. This avoids the outer surface of the hollow fiber membrane 2 from being covered with a thick layer of aged biofilm and hard scale layer, thereby reducing the difficulty of cleaning the hollow fiber membrane 2. During cleaning, the lifting component 43 first drives the flexible filter cylinder 41 to move downward relative to the hollow fiber membrane 2, thereby causing the flexible filter cylinder 41 to move the aged biofilm and hard scale layer on the outside of the hollow fiber membrane 2 downward. After the flexible filter cylinder 41 detaches from the lower end of the hollow fiber membrane 2, it moves to the connecting rod. At this time, most of the aged biofilm and hard scale layer are cleaned to the lower end of the hollow fiber membrane 2.

[0047] like Figures 2-7 As shown, the lifting assembly 43 includes a connecting plate 431, a base plate 432, and a driving component. The upper end of the hollow fiber membrane 2 is fixedly connected to the connecting plate 431, and the lower end of the hollow fiber membrane 2 is fixedly connected to the base plate 432. Multiple sliding rods 13 extend downward from the lower end surface of the mounting frame 1. The sliding rods 13 pass through both the connecting plate 431 and the base plate 432. The driving component is used to drive the connecting plate 431 and the base plate 432 to move downward simultaneously first, and then to move the connecting plate 431 downward relative to the base plate 432, so that the distance between the connecting plate 431 and the base plate 432 gradually increases. During the shortening process, the upper and lower ends of the flexible filter cylinder 41 gradually approach each other, causing the portion of the flexible filter cylinder 41 located below the connecting rod to loosen and deform. When the connecting plate 431 moves to the connecting rod on the hollow fiber membrane 2, the driving component drives the connecting plate 431 to move upward, causing the deformed flexible filter cylinder 41 to gradually straighten again. This process is repeated multiple times, causing the flexible filter cylinder 41 to switch between loosening and straightening multiple times, thereby shaking off most of the aged biofilm and hard scale layer attached to the surface of the flexible filter cylinder 41.

[0048] like Figures 2-7 As shown, the driving component includes a lead screw 433 and a motor 434. The lead screw 433 is rotatably mounted on the mounting bracket 1, and the motor 434 is fixedly mounted on the mounting bracket 1. The output end of the motor 434 is connected to the lead screw 433. The lead screw 433 passes through both the connecting plate 431 and the base plate 432, and the lead screw 433 is threadedly engaged with both the connecting plate 431 and the base plate 432. The lower end of the lead screw 433 extends downward with a smooth section, which is located below the connecting rod. The lower end of the slide rod 13 is provided with a limiting member for blocking the base plate 432.

[0049] Initially, the upper end of the flexible filter cylinder 41 is located at the hollow tube on the hollow fiber membrane 2, and the lower end of the flexible filter cylinder 41 is located at the connecting rod at the lower end of the hollow fiber membrane 2. When cleaning the hollow fiber membrane 2, the motor 434 drives the lead screw 433 to rotate forward, causing the connecting plate 431 and the bottom plate 432 to move downwards simultaneously relative to the hollow fiber membrane 2. When the lower end of the flexible filter cylinder 41 is located on the connecting rod at the lower end of the hollow fiber membrane 2, the bottom plate 432 contacts the limiting member at the bottom end of the slide rod 13, and at this time the bottom plate 432 is located at the smooth section at the lower end of the lead screw 433. As the lead screw 433 continues to rotate forward, the bottom plate 432 stops moving downwards due to disengagement from the lead screw 433 and being blocked by the limiting member. At this time, the connecting plate 431 moves downwards under the drive of the lead screw 433, and simultaneously... As the connecting plate 431 and the base plate 432 gradually approach each other, the part of the flexible filter cylinder 41 below the connecting rod loosens and deforms. When the upper end of the flexible filter cylinder 41 moves to the connecting rod on the hollow fiber membrane 2, the motor 434 reverses and drives the lead screw 433 to reverse, thereby causing the connecting plate 431 to move upward, so that the flexible filter cylinder 41 is re-fitted onto the hollow fiber membrane 2. During this process, the flexible filter cylinder 41 gradually returns to a taut state. When the flexible filter cylinder 41 is taut, the motor 434 rotates forward again and causes the lead screw 433 to rotate forward. Then the above process is repeated many times. During the process of the flexible filter cylinder 41 changing from taut to loose deformation and then back to taut, most of the aged biofilm and hard scale layer attached to the surface of the flexible filter cylinder 41 are shaken off.

[0050] like Figures 6-7 As shown, the limiting component includes an annular platform 14 disposed at the bottom end of the slide bar 13. When the base plate 432 moves to the smooth section of the lead screw 433, it abuts against the annular platform 14. The annular platform 14 is used to block the base plate 432 and prevent it from moving further downward.

[0051] like Figures 2-7As shown, the cleaning assembly 42 includes multiple cleaning rings 421 and a driving component 2. The cleaning rings 421 are rotatably mounted on the connecting plate 431 and are located at the upper end of the flexible filter cylinder 41. Multiple cleaning rings 421 are sleeved on multiple hollow fiber membranes 2. Brushes are provided on the inner circumferential wall of the cleaning rings 421, with one end of the brush facing the hollow fiber membrane 2 abutting against the outer surface of the hollow fiber membrane 2. The driving component 2 is used to move up and down relative to the hollow fiber membrane 2 at the upper end of the flexible filter cylinder 41, causing the cleaning rings 421 to rotate clockwise and counterclockwise, thereby causing the cleaning rings 421 to rotate. The brush on 1 cleans the outer surface of the hollow fiber membrane 2. Since the outer surface of the hollow fiber membrane 2 is fitted with a flexible filter cylinder 41, and the inner surface of the flexible filter cylinder 41 is in contact with the outer surface of the hollow fiber membrane 2, the aged biofilm and hard scale layer attached to the outer surface of the hollow fiber membrane 2 are relatively thin. Therefore, the outer surface of the hollow fiber membrane 2 can be cleaned without a large cleaning force, avoiding damage to the outer surface of the hollow fiber membrane 2 caused by a thicker layer of aged biofilm and hard scale layer.

[0052] like Figures 6-7 As shown, the driving component two includes multiple gears: gear one 422, gear two 423, gear three 424, and gear four 425. The gears one 422 are respectively sleeved on multiple cleaning rings 421, and adjacent gears one 422 mesh with each other. Gears two 423, gear three 424, and gear four 425 are all rotatably mounted on the connecting plate 431. Gear two 423 is sleeved on the lead screw 433, and gear two 423 meshes with gear three 424. Gear three 424 meshes with gear four 425, and gear four 425 meshes with one of the gears one 422. The lead screw... A groove is provided on gear 433, and a slider 426 is fixedly installed on gear 423. The slider 426 is slidably installed in the groove in the vertical direction. When motor 434 drives lead screw 433 to rotate, lead screw 433 drives gear 423 to rotate through the groove. When gear 423 rotates, it drives gear 422 to rotate, which in turn drives the cleaning rings 421 on all flexible filter cylinders 41 to rotate. When lead screw 433 rotates forward and reverse, cleaning rings 421 can clean the surface of hollow fiber membrane 2 from two opposite directions on the outer surface of hollow fiber membrane 2.

[0053] like Figures 2-7 As shown, the mounting frame 1 is also equipped with a water inlet pipe 15 and multiple water spray nozzles 16. The water inlet pipe 15 is used to supply water to the multiple water spray nozzles 16. The water spray nozzles 16 are used to spray water onto the outer surface of the hollow fiber membrane 2 from the upper end of the hollow fiber membrane 2. When the brush on the cleaning ring 421 cleans the hollow fiber membrane 2, the water sprayed from the water spray nozzles 16 washes away the aged biofilm and hard scale layer cleaned off by the brush.

[0054] The base plate 432 is also equipped with a second water inlet pipe 44 and multiple second water spray nozzles 45. The second water inlet pipe 44 is used to supply water to the multiple second water spray nozzles 45. The second water spray nozzles 45 are used to spray water onto the flexible filter screen cylinder 41 above. When the flexible filter screen cylinder 41 changes between loosening and straightening multiple times, the second water spray nozzles 45 spray water onto the aged biofilm and hard scale layer attached to the outer surface of the flexible filter screen cylinder 41, thereby making it easier for the aged biofilm and hard scale layer to fall off.

[0055] A wastewater treatment method includes the following steps:

[0056] S1. During operation, the worker first places the mounting frame 1 and the hollow fiber membrane 2 into the sewage tank. Air enters the hollow fiber membrane 2 through the air inlet pipe 11, and then flows downward from the upper end of the hollow fiber membrane 2 until it reaches the bottom end of the hollow fiber membrane 2. Then it enters the exhaust pipe 3 from the lower end of the exhaust pipe 3, and finally is discharged to the outside through the air outlet pipe 12. Oxygen in the air inside the hollow fiber membrane 2 passes through the hollow fiber membrane 2 and enters the aerobic zone on the surface of the hollow fiber membrane 2 to provide oxygen for bacteria.

[0057] S2. After the hollow fiber membrane 2 has been working for a period of time, the worker will remove the installation frame 1 and the hollow fiber membrane 2 from the sewage tank, and then start the motor 434 to drive the lead screw 433 to rotate forward. When the lead screw 433 rotates forward, it will drive the connecting plate 431 and the bottom plate 432 to descend. At the same time, the water spray nozzle 16 on the connecting plate 431 and the water spray nozzle 2 45 on the bottom plate 432 will spray water outward.

[0058] S3. The cleaning of hollow fiber membrane 2 includes the following steps:

[0059] S31, after the bottom plate 432 disengages from the lead screw 433 and stops moving downward due to the obstruction of the ring platform 14, the connecting plate 431 moves downward under the drive of the lead screw 433. At the same time, as the connecting plate 431 and the bottom plate 432 gradually approach each other, the part of the flexible filter cylinder 41 below the connecting rod on the hollow fiber membrane 2 becomes loose and deformed.

[0060] S32. When the upper end of the flexible filter cylinder 41 moves to the connecting rod on the hollow fiber membrane 2, the motor 434 reverses and drives the lead screw 433 to reverse, thereby causing the connecting plate 431 to move upward, so that the flexible filter cylinder 41 is re-fitted onto the hollow fiber membrane 2. During this process, the flexible filter cylinder 41 gradually returns to a taut state.

[0061] S33. When the flexible filter cylinder 41 is straightened, the motor 434 rotates forward again and the lead screw 433 rotates forward. Then the above process is repeated many times. When the upper end of the flexible filter cylinder 41 moves up and down relative to the hollow fiber membrane 2, the cleaning ring 421 rotates forward and reverse. The brush on the cleaning ring 421 cleans the outer surface of the hollow fiber membrane 2. The water sprayed from the nozzle 16 washes away the aging biofilm and hard scale layer cleaned by the brush. During the process of the flexible filter cylinder 41 changing from straight to loose deformation and then straightening again, most of the aging biofilm and hard scale layer attached to the surface of the flexible filter cylinder 41 is shaken off. The nozzle 2 45 sprays water onto the aging biofilm and hard scale layer attached to the outer surface of the flexible filter cylinder 41, making it easier for the aging biofilm and hard scale layer to fall off.

[0062] S4. After cleaning the outer surface of the hollow fiber membrane 2 and the flexible filter cylinder 41, the water spray nozzle 16 and the water spray nozzle 2 45 stop spraying water. Then, the motor 434 reverses and drives the screw 433 to reverse, causing the connecting plate 431 to move upward. When the flexible filter cylinder 41 is straightened, as the screw 433 continues to reverse, the connecting plate 431 continues to move upward. At this time, the connecting plate 431 drives the bottom plate 432 to move upward through the flexible filter cylinder 41 until the flexible filter cylinder 41 is reset. Finally, the worker puts the mounting frame 1 and the hollow fiber membrane 2 into the sewage tank.

[0063] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A modular wastewater treatment device based on MABR, comprising a mounting frame (1) and a hollow fiber membrane (2) disposed on the mounting frame (1), wherein the mounting frame (1) is provided with an air inlet pipe (11) and an air outlet pipe (12), characterized in that, Also includes: The exhaust pipe (3) is installed inside the hollow fiber membrane (2). The upper end of the hollow fiber membrane (2) is connected to the air inlet pipe (11), and the lower end is closed. The upper end of the exhaust pipe (3) is connected to the air outlet pipe (12). The gas inside the hollow fiber membrane (2) is discharged from the air outlet pipe (12) through the exhaust pipe (3). The cleaning mechanism (4) includes a flexible filter cylinder (41) sleeved on the hollow fiber membrane (2) and a lifting assembly (43) for raising and lowering the flexible filter cylinder (41) in the vertical direction. The inner circumferential wall of the flexible filter cylinder (41) is attached to the outer circumferential wall of the hollow fiber membrane (2), and the hollow fiber membrane (2) is completely located inside the flexible filter cylinder (41).

2. The modular wastewater treatment device based on MABR according to claim 1, characterized in that, The hollow fiber membrane (2) is provided with multiple hollow fiber membranes (2), and each hollow fiber membrane (2) is covered with a flexible filter cylinder (41).

3. A modular wastewater treatment device based on MABR according to claim 2, characterized in that, The lifting assembly (43) includes a connecting plate (431) that is slidably mounted on the mounting frame (1) in the vertical direction and a driving component for driving the connecting plate (431) to lift. The upper end of the flexible filter cylinder (41) is fixedly connected to the connecting plate (431).

4. A modular wastewater treatment device based on MABR according to claim 3, characterized in that, The drive unit includes a lead screw (433) rotatably mounted on the mounting bracket (1) and a motor (434) fixedly mounted on the mounting bracket (1). The output end of the motor (434) is connected to the lead screw (433). The lead screw (433) passes through the connecting plate (431) and is threadedly engaged with the connecting plate (431). A slide rod (13) is provided on the mounting bracket (1) and passes through the connecting plate (431).

5. A modular wastewater treatment device based on MABR according to claim 4, characterized in that, The upper end of the flexible filter cylinder (41) is provided with a cleaning ring (421), and the cleaning ring (421) is sleeved on the hollow fiber membrane (2). A brush is provided on the inner circumferential wall of the cleaning ring (421), and the end of the brush facing the hollow fiber membrane (2) abuts against the hollow fiber membrane (2).

6. A modular wastewater treatment device based on MABR according to claim 5, characterized in that, Gear 1 (422) is sleeved on the cleaning ring (421), and two adjacent gears 1 (422) mesh with each other. Gear 2 (423) is installed on the connecting plate (431). Gear 2 (423) slides in the vertical direction and is sleeved on the lead screw (433). Gear 2 (423) meshes with one of the gears 1 (422).

7. A modular wastewater treatment device based on MABR according to claim 4, characterized in that, The mounting bracket (1) has a base plate (432) that slides vertically. The bottom end of the flexible filter cylinder (41) is fixedly installed on the base plate (432). The slide rod (13) and the lead screw (433) are both installed on the base plate (432). The lead screw (433) and the base plate (432) are threadedly engaged. The slide rod (13) is provided with a limiting component, which is used to limit the base plate (432) after the connecting plate (431) and the base plate (432) descend together by a certain distance.

8. A modular wastewater treatment device based on MABR according to claim 7, characterized in that, The limiting component includes an annular platform (14) at the bottom of the slide bar (13), and a smooth section at the lower end of the lead screw (433). When the base plate (432) moves to the smooth section of the lead screw (433), it abuts against the annular platform (14). As the lead screw (433) rotates, the connecting plate (431) continues to descend and deforms the flexible filter cylinder (41).

9. A modular wastewater treatment device based on MABR according to claim 7, characterized in that, The mounting frame (1) is provided with multiple water spray nozzles (16) for spraying water onto the hollow fiber membrane (2) from the top end of the hollow fiber membrane (2). The base plate (432) is provided with multiple water spray nozzles (45) for spraying water onto the flexible filter cylinder (41) above.

10. A wastewater treatment method, characterized in that, The modular wastewater treatment device based on MABR as described in claim 8 includes the following steps: S1. First, the hollow fiber membrane (2) is placed in the sewage tank. Then, air is sent into the air inlet pipe (11) on the mounting frame (1). Oxygen enters the hollow fiber membrane (2) through the air inlet pipe (11). The oxygen in the hollow fiber membrane (2) passes through the hollow fiber membrane (2) and enters the aerobic zone on the surface of the hollow fiber membrane (2) to provide oxygen for bacteria. S2. After the hollow fiber membrane (2) has been working for a period of time, the mounting frame (1) and the hollow fiber membrane (2) are lifted out of the sewage tank, and then the motor (434) is started to lower the connecting plate (431) and the bottom plate (432). S3. After the base plate (432) is limited by the ring platform (14), the lead screw (433) continues to rotate to lower the connecting plate (431). When the connecting plate (431) moves to the smooth section of the lead screw (433), the motor (434) reverses to raise the connecting plate (431) a certain distance. Then, the motor (434) rotates forward again to lower the connecting plate (431), thereby deforming the flexible filter cylinder (41) and shaking off the dirt. S4. After cleaning, reset the flexible filter cylinder (41), and finally put the mounting bracket (1) and hollow fiber membrane (2) into the sewage tank.

Images