In-situ cleaning method for MBR (Membrane Bioreactor) membrane

Abstract

The invention discloses an MBR membrane in-situ cleaning method which comprises the following steps: S1, hoisting an in-situ cleaning device above an MBR membrane frame, putting a positioning pin into a positioning groove of the MBR membrane frame, and inserting a limiting pin into a limiting hole of an MBR membrane frame limiting plate; s2, after the in-situ cleaning device and an MBR membrane frame are fixed, a water pump and a servo motor are started, the servo motor drives a lead screw to rotate, a movable platform moves downwards along with rotation of the lead screw, meanwhile, under the action of the water pump, cleaning water is conveyed to a cleaning assembly through a water distribution pipe, and an MBR membrane is subjected to high-pressure water washing through a cleaning head; s3, after cleaning is completed, the rotating direction of the servo motor is changed, the cleaning assembly is restored to the original position, the position of the in-situ cleaning device is moved, and the operation from S1 to S3 is repeated to clean other MBR membranes till all the MBR membranes are cleaned. According to the system, in-situ online cleaning can be carried out under the state that the system is not shut down and does not need to be disassembled, the cleaning efficiency is greatly improved, the labor intensity is reduced, meanwhile, the water consumption is reduced, and the energy consumption is reduced.

Description

Technical Field

[0001] The invention relates to the field of MBR membrane in-situ cleaning, and in particular to an MBR membrane in-situ cleaning method. Background Art

[0002] MBR membrane, also known as membrane bioreactor, is a new water treatment technology that combines a membrane separation unit with a biological treatment unit. It mainly utilizes the activated sludge and macromolecular organic matter in the interception trough of the MBR membrane component immersed in the aerobic biological pool. Due to its effective interception effect, it can retain microorganisms with a longer generation cycle and achieve deep purification of sewage.

[0003] During the use of MBR membranes, membrane fouling has always restricted the development of membrane separation technology. During the operation of MBR membranes, due to the high concentration of sludge, it is easy to accumulate on the surface of the MBR membrane, especially at the roots of the two ends of the MBR membrane, causing MBR membrane pollution. At present, in order to prevent MBR membrane pollution, an aeration device is installed under the MBR membrane to remove pollutants on the surface of the membrane filaments through aeration. When aeration fails, sludge is easy to form a hard surface on the surface of the membrane filaments, and the MBR membrane is irreversibly polluted. In addition, pollutants such as extracellular polymers are easy to form a firm filter cake layer on the surface of the membrane filaments, which is difficult to remove by aeration. When the MBR membrane filaments are hardened or irreversibly polluted, the curtain membrane assembly can usually only be removed from the membrane frame for flushing. The disassembly and assembly of the membrane assembly is cumbersome, time-consuming and labor-intensive, and the amount of work is large, which seriously affects the cleaning efficiency.

[0004] Chinese Patent No. 2021220753235 discloses an MBR membrane in-situ cleaning tool, including a cleaning pipe and a hand grip, the hand grip is fixedly installed at the end of the cleaning pipe, and the hand grip is connected to the cleaning pipe, the end of the cleaning pipe away from the hand grip is provided with an end spray hole, and the cleaning pipe is provided with side spray holes on both sides of the end spray hole, the hand grip is a retractable structure, including an outer pipe and an inner pipe, and a sealing device is fixedly installed at the upper end of the inner pipe. Although this patent can achieve in-situ cleaning, the actual membrane frame is about 2m high, and the cleaning pipe goes from the upper end of the membrane frame to the lower end of the membrane frame for cleaning, which is difficult to achieve only with a hand grip, and the operability needs to be verified. Summary of the invention

[0005] Technical problem: In order to solve the above problems, the present invention provides an MBR membrane in-situ cleaning method, which can realize in-situ online cleaning. That is, when the MBR membrane is blocked by dirt, there is no need to remove the curtain membrane from the membrane frame for flushing, which greatly reduces the amount of engineering work, improves the cleaning efficiency, is simple to operate, and is easy to implement.

[0006] The present invention adopts the water in the original membrane pool for cleaning, thus saving water.

[0007] The in-situ cleaning device provided by the present invention has a simple structure, is detachable, and is easy to maintain; when cleaning the MBR membrane, the mechanical structure of the in-situ cleaning device is above the water surface, is not easily damaged, and is easy to maintain.

[0008] The present invention uses high-pressure water impact force to break up large pieces of mud on the surface of the MBR membrane, has good cleaning effect, strong anti-pollution performance, and can reduce aeration volume and save energy consumption.

[0009] The structure of the invention is ingenious and can be quickly installed and fixed on the MBR membrane frame.

[0010] Technical solution: To solve the above technical problems, the present invention also provides an in-situ cleaning method, comprising:

[0011] S1: hoist the in-situ cleaning device above the MBR membrane frame, put the limit pin into the positioning groove of the MBR membrane frame, and insert the limit pin into the limit hole of the MBR membrane frame;

[0012] S2 After fixing the in-situ cleaning device to the MBR membrane frame, turn on the water pump and the servo motor, the servo motor drives the screw to rotate, the mobile platform moves down with the screw, and the cleaning component moves down to the middle of the two MBRs. At the same time, under the action of the water pump, the cleaning water is transported to the cleaning component through the water distribution pipe, and the MBR membrane is washed with high-pressure (0-0.6Mpa) water through the cleaning head. The speed and residence time of the mobile platform are adjusted according to the cleaning effect;

[0013] After S3 cleaning is completed, the servo motor direction is changed, the cleaning assembly is restored to its original position, the position of the in-situ cleaning device is moved, and the operations S1-S3 are repeated to clean the remaining MBR membranes until all the MBR membranes are cleaned;

[0014] S4 restores the cleaning component to its original position and removes the in-situ cleaning device.

[0015] Also provided is an MBR membrane in-situ cleaning device, comprising a main frame, a cleaning assembly and a mobile platform; the main frame is a three-dimensional structure, and is provided with a positioning light rod and a screw rod, the screw rod is connected to a servo motor, the positioning light rod and the screw rod pass through the mobile platform and are detachably fixed to the main frame, a slider is provided on the screw rod, the slider is located below the mobile platform, the inner ring of the slider is provided with a thread matching the screw rod, the mobile platform can move on the slide rod and the screw rod, and the position of the mobile platform is controlled by the slider on the screw rod;

[0016] The cleaning assembly includes a cleaning head and a connecting rod. The cleaning head is a hollow structure and has water spray ports on the side and bottom. The cleaning head is preferably a hollow cylindrical structure to prevent damage to the membrane fibers during operation. The connecting rod is a hollow structure. The cleaning head and the connecting rod are connected. The cleaning liquid is transported from the connecting rod to the cleaning head and sprayed from the water spray port of the cleaning head. The mud blocks on the surface of the MBR membrane or the filter cake layer attached to the membrane surface that is not easily removed by air scrubbing are crushed by high-pressure water impact.

[0017] The mobile platform is provided with through holes, the aperture, number and shape of which match the connecting rod, ensuring that the connecting rod of the cleaning component can pass through the through hole of the mobile platform and be connected to the water distribution pipe; the mobile platform is provided with a water pump, one end of which is connected to the water suction pipe and the other end is connected to the water distribution pipe, and the water distribution pipe is above the mobile platform; the mobile platform, the cleaning component, the water pump and the water suction pipe form a mobile whole, and move on the main frame together with the mobile platform

[0018] Furthermore, the number of the cleaning components is ≥ 1, and they can be arranged in a single row or in multiple rows in parallel. Different numbers and arrangements of cleaning components can be set according to the width of the MBR membrane and the number of MBRs to be cleaned.

[0019] Furthermore, the water distribution pipe is composed of a plurality of tees connected in series, which is more convenient for disassembly and local maintenance.

[0020] Furthermore, a positioning pin and a limit pin are provided at the bottom of the main frame.

[0021] Furthermore, the positioning pin is cylindrical, which is convenient for matching with the film frame and can achieve rapid positioning.

[0022] Furthermore, the limit pin is a straight-line limit pin, which can prevent the cleaning device from tipping over due to impact force during the cleaning process.

[0023] Furthermore, the straight-line limit pins are located on the same side and are respectively connected to connecting rods, and the connecting rods are connected to the rotating cylinder through a turntable and a rotating shaft. By controlling the rotating cylinder, the extension or retraction of the straight-line limit pins is controlled, which facilitates installation and disassembly.

[0024] Furthermore, a filtering device is provided at the water inlet of the water suction pipe, preferably a filter screen with a filtering accuracy of 0.5-2mm, which is used to filter impurities in the cleaning water.

[0025] Furthermore, an air intake pipe is provided on the water suction pipe, and the air intake pipe is connected to the air intake device and is used to remove impurities adsorbed on the filter device.

[0026] The present invention also provides an MBR membrane frame, which is an MBR membrane frame used in conjunction with the MBR membrane in-situ cleaning method. The MBR membrane frame is a square three-dimensional structure, and limit plates are provided on the upper brackets on both sides of the membrane frame. The limit plates are provided with positioning grooves and limit holes.

[0027] Furthermore, the positioning groove and the limiting hole match the positioning pin and the limiting pin of the in-situ cleaning device.

[0028] Furthermore, the positioning groove is a V-shaped structure.

[0029] Furthermore, the limiting hole is a straight-line structure, which can prevent the cleaning device from rotating during operation and make the limiting more secure.

[0030] Beneficial effects: Compared with the prior art, the technical solution of the present invention has the following beneficial effects: after the in-situ cleaning device provided by the present invention is fixed to the MBR membrane frame, the cleaning component can be extended into the space between the two MBR membranes for high-pressure water flushing under mechanical action, without stopping the system operation, without lifting the MBR membrane frame out of the membrane pool, and without pumping out the water in the membrane pool. The cleaning effect is good, the operation is simple and easy to implement.

[0031] The present invention provides a filtering device at the end of the water suction pipe, and can directly use the water in the membrane pool for flushing, thus saving water.

[0032] The present invention arranges a fixing pin, a straight limit pin and a rotating mechanism at the bottom of the in-situ cleaning device, and arranges a positioning groove and a limit hole on the MBR membrane frame, so that the in-situ cleaning device and the MBR membrane frame can be quickly fixed together, and the straight limit pin can prevent the cleaning device from rotating and tipping over due to impact force during the cleaning process.

[0033] When the in-situ cleaning device provided by the present invention is used, it is placed on the MBR membrane frame, only the cleaning component extends into the MBR, and all mechanical structures are above the water surface, so the mechanical structures are not easily corroded or damaged.

[0034] The in-situ cleaning device provided by the present invention has a simple structure and is detachable, so it is convenient for daily maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a three-dimensional schematic diagram of an in-situ cleaning device according to an embodiment of the present invention.

[0036] Figure 2 It is a front view of an in-situ cleaning device according to an embodiment of the present invention.

[0037] Figure 3 1 is a top view of an in-situ cleaning device according to an embodiment of the present invention.

[0038] Figure 4 It is a schematic diagram of an in-situ cleaning component according to an embodiment of the present invention.

[0039] Figure 5 The present invention Figure 4 Enlarged view of the middle cleaning head (B).

[0040] Figure 6 It is a left view of the main frame of the in-situ cleaning device according to one embodiment of the present invention.

[0041] Figure 7 The present invention Figure 5 Cross-sectional view of the middle I-shaped limit pin in the retracted state.

[0042] Figure 8 The present invention Figure 5 Cross-sectional view of the extended state of the middle I-shaped limit pin.

[0043] Fig. 9 It is a schematic diagram of the membrane frame structure in one embodiment of the present invention.

[0044] Fig.10 yes Fig. 9 A partial enlarged view of point I in the middle.

[0045] Fig.11 It is a schematic diagram of the assembly of the in-situ cleaning device and the membrane frame in the present invention.

[0046] Fig.12 yes Fig.10 A partial enlarged view of point H in the middle.

[0047] Fig.13 It is the state in which the cleaning component in the in-situ information device is displaced to the middle of the membrane frame.

[0048] Fig.14 It is the state in which the cleaning component in the in-situ information device is displaced to the bottom of the membrane frame.

[0049] Fig.15 yes Figure 1 A partial enlarged view of the middle positioning pin (B).

[0050] Fig.16 yes Figure 1 A partial enlarged view of the middle limit pin (A).

[0051] Fig.17 yes Figure 1 A partial enlarged view of the middle filtration device (C).

[0052] The figure includes: 1. main frame; 2. positioning rod; 3. cleaning assembly; 4. moving platform plate; 5. screw rod; 6. screw rod linkage shaft; 7. rotating cylinder; 8. servo motor; 9. water distribution pipe; 10. air inlet pipe; 11. water pump; 12. water suction pipe; 13. filtering device; 14. slider; 15. positioning pin; 16. limit pin; 17. connecting rod; 18. cleaning head; 19. water spray nozzle; 20. rotating shaft; 21. connecting rod; 22. turntable; 23. limit sleeve; 24. limit plate; 25. positioning groove; 26. limit hole. DETAILED DESCRIPTION

[0053] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings.

[0054] The present invention also provides an in-situ cleaning method, comprising:

[0055] S1: hoist the in-situ cleaning device above the MBR membrane frame, put the limit pin into the positioning groove of the MBR membrane frame, and insert the limit pin into the limit hole of the limit plate of the MBR membrane frame;

[0056] S2 After fixing the in-situ cleaning device to the MBR membrane frame, turn on the water pump and the servo motor, the servo motor drives the screw to rotate, and the mobile platform moves down with the screw. At the same time, under the action of the water pump, the cleaning water is transported to the cleaning component through the water distribution pipe, and the MBR membrane is washed with high-pressure water through the cleaning head. The general pressure range is 0-0.6Mpa, and the corresponding pressure value is selected according to the degree of contamination of the MBR membrane;

[0057] After S3 cleaning is completed, the servo motor direction is changed, the cleaning assembly is restored to its original position, the position of the in-situ cleaning device is moved, and the operations S1-S3 are repeated to clean the remaining MBR membranes until all the MBR membranes are cleaned;

[0058] S4 restores the cleaning component to its original position and removes the in-situ cleaning device.

[0059] The present invention also provides an MBR membrane in-situ cleaning device such as Figure 1-17 , including a main frame 1, a cleaning assembly 3 and a mobile platform 4; the main frame 1 is a three-dimensional structure, preferably a rectangular parallelepiped or cube structure, and a positioning light rod 2 and a screw rod 5 are provided on the main frame 1, and the screw rod 5 is connected to a servo motor 8. The positioning light rod 2 and the screw rod 5 pass through the mobile platform 4 and are detachably fixed to the main frame 1, and the mobile platform can move freely on the light rod and the screw rod;

[0060] In one embodiment, two screw rods 5 are provided, and the two screw rods 5 are connected via a screw rod linkage shaft 6 .

[0061] The cleaning assembly 3 includes a cleaning head 18 and a connecting rod 17. The cleaning head 18 is a hollow structure and has water spray ports 19 on the side and bottom. The cleaning head 18 is preferably a hollow cylindrical structure to avoid damaging the membrane fibers when cleaning the MBR membrane. The connection 17 is a hollow structure. The cleaning head 18 is connected to the connecting rod 17. The cleaning liquid (or water) is transported from the connecting rod 17 to the cleaning head 18 and sprayed from the water spray port 19 of the cleaning head 18. The mud blocks on the surface of the MBR membrane are cleaned by high-pressure water impact.

[0062] The number of the cleaning components 3 is ≥ 1, which can be arranged in one row or multiple rows in parallel, and can clean one or more groups of MBR membranes at the same time;

[0063] In one embodiment, Figure 1-3 In the embodiment, the cleaning components are arranged in three parallel rows, and three groups of MBR membranes can be cleaned simultaneously.

[0064] The mobile platform 4 is provided with a through hole, the aperture, number and shape of which match the connecting rod 17, ensuring that the connecting rod 17 can pass through the through hole of the mobile platform 4; a water pump 11 is provided on the mobile platform 4, one end of the water pump 11 is connected to the water suction pipe 12, and the other end is connected to the water distribution pipe 9; the connecting rod 17 of the cleaning component 3 passes through the through hole of the mobile platform 4 and is connected to the water distribution pipe 9; the water distribution pipe 9 is above the mobile platform 4; the mobile platform 4, the cleaning component 3, the water distribution pipe 9, the water pump 11 and the water suction pipe 12 form a whole, which can move up and down along the positioning light rod 2;

[0065] In one embodiment, the water distribution pipe 9 is composed of a plurality of tee pipes, which is convenient for assembly and disassembly.

[0066] The lead screw 5 is provided with a slider 14, which is located below the mobile platform 4. The inner ring of the slider 14 is provided with a thread that matches the lead screw, providing a limit function for the mobile platform 4. After the servo motor 8 is turned on, the servo motor 8 drives the lead screw 5 to rotate, thereby causing the slider 14 to move on the lead screw 5, and the mobile platform 4 also moves accordingly.

[0067] In one embodiment, a filtering device 13 is provided at the water inlet of the water distribution pipe 9 for filtering impurities in the cleaning water. Furthermore, water in the membrane pool can be directly drawn for cleaning.

[0068] In one embodiment, the filtering device 13 is a filter screen with a filtering accuracy of 0.5-2 mm.

[0069] In one embodiment, a positioning pin 15 and a limiting pin 16 are provided at the bottom of the main frame 1. The positioning pin is cylindrical for quick positioning. The limiting pin is a straight-line limiting pin, which is not easy to fall off after matching with the limiting hole for limiting positioning.

[0070] In one embodiment, the straight-line limiting pins 16 are located on the same side and are respectively connected to the connecting rods 21 , and the connecting rods 21 are connected to the rotary cylinder 7 via the rotating disk 22 and the rotating shaft 20 .

[0071] In one embodiment, an air intake pipe 10 is provided on the water suction pipe 12, and the air intake pipe 10 is connected to an air intake device. When the water suction pipe 12 is blocked by dirt, the air intake device is opened to blow gas into the water suction pipe through the air intake pipe 10 to remove impurities outside the filter.

[0072] The present invention also provides an MBR membrane frame, which can be used in combination with the MBR membrane in-situ cleaning method. The MBR membrane frame is a square three-dimensional structure, and the upper brackets on both sides of the membrane frame are provided with limit plates 24, and the limit plates 24 are provided with positioning grooves 25 and limit holes 26. Further, the positioning grooves and limit holes match the positioning pins and limit pins of the in-situ cleaning device.

[0073] In one embodiment, the positioning groove is a V-shaped structure.

[0074] In one embodiment, the limiting hole is a straight-line structure.

[0075] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above specific embodiments. The above specific embodiments and the description in the specification are only for further illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of the present invention to be protected is defined by the claims and their equivalents.

Claims

1. The present invention also provides an in-situ cleaning method, characterized in that: include: S1: hoist the in-situ cleaning device above the MBR membrane frame, put the positioning pin into the positioning groove of the MBR membrane frame, and insert the limiting pin into the limiting hole of the limiting plate of the MBR membrane frame; S2: After the in-situ cleaning device is fixed to the MBR membrane frame, the water pump and the servo motor are turned on. The servo motor drives the screw to rotate, and the mobile platform moves down with the rotation of the screw. The cleaning component moves down to the middle of the two MBRs. At the same time, under the action of the water pump, the cleaning water is transported to the cleaning component through the water distribution pipe, and the MBR membrane is washed with high-pressure water through the cleaning head; S3: After the cleaning is completed, the servo motor direction is changed, the cleaning assembly is restored to its original position, the position of the in-situ cleaning device is moved, and the S1-S3 operations are repeated to clean the remaining MBR membranes until all the MBR membranes are cleaned; S4: Return the cleaning component to its original position and remove the in-situ cleaning device. The in-situ cleaning device comprises a main frame (1), a cleaning assembly (3) and a moving platform (4); the main frame (1) is a three-dimensional structure, and a positioning light rod (2) and a screw rod (5) are provided on the main frame (1); the screw rod (5) is connected to a servo motor (8); the positioning light rod (4) and the screw rod (5) pass through the moving platform (4) and are detachably fixed to the main frame (1); and the moving platform (4) can move freely on the positioning light rod (2) and the screw rod (5); The screw rod (5) is provided with a slider (14), the slider (14) is located below the moving platform (4), and the inner ring of the slider (14) is provided with a thread matching the screw rod (5). The cleaning assembly (3) comprises a cleaning head (18) and a connecting rod (17); the cleaning head (18) is a hollow structure and is provided with water spray ports (19) on the side and the bottom; the connecting rod (17) is a hollow structure; one end of the connecting rod (17) is connected to the cleaning head (18); the other end passes through a through hole of the mobile platform (4) and is connected to a water distribution pipe (9); the water distribution pipe (9) distributes the cleaning liquid, transports it to the cleaning head (18) through the connecting rod (17), and sprays it out from the water spray port (19) of the cleaning head, using high-pressure water to impact and break up mud blocks on the surface of the MBR membrane or filter cake layers attached to the membrane surface that are not easily removed by air scrubbing; The mobile platform (4) is provided with a water pump (11), one end of the water pump (11) is connected to a water suction pipe (12), and the other end is connected to a water distribution pipe (9); The MBR membrane frame is a square three-dimensional structure. Limiting plates are provided on the upper brackets on both sides of the membrane frame. The limiting plates are provided with positioning grooves and limiting holes; the positioning grooves and limiting holes match the positioning pins and limiting pins of the in-situ cleaning device.

2. A MBR membrane in-situ cleaning method according to claim 1, characterized in that: In S2, one or more groups of MBR membranes can be cleaned simultaneously.

3. A MBR membrane in-situ cleaning method according to claim 1, characterized in that: The speed at which the mobile platform moves downward and the dwell time thereof are determined according to the on-site cleaning effect.

4. A MBR membrane in-situ cleaning method according to claim 1, characterized in that: A filtering device is provided at the water inlet of the water suction pipe, and the cleaning liquid can be water from the original MBR membrane pool.

5. A MBR membrane in-situ cleaning method according to claim 4, characterized in that: The filtering accuracy of the filtering device is 0.5-2mm.

6. A MBR membrane in-situ cleaning method according to claim 1, characterized in that: The high pressure range is 0-0.6Mpa.

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