A Multistage AO Improved High-Efficiency Denitrification Control Device and Method Based on MABR

Abstract

The present invention relates to the technical field of wastewater treatment, and particularly relates to a multi-stage AO improved high-efficiency denitrification control device and method based on MABR. The device comprises an anaerobic tank, an anoxic tank, an anoxic-aerobic tank and an aerobic tank which are sequentially connected through pipelines. A cross plate, a first partition board, a second partition board, a third partition board and a fourth partition board are fixedly connected in the aerobic tank. The bottom end of the first partition board is fixedly connected with the bottom end of the aerobic tank, and gaps are respectively arranged between the second partition board, the third partition board, the fourth partition board and the bottom end of the aerobic tank. A lifting and rotating device is arranged at the center of the cross plate, the lifting and rotating device is connected with a cover plate, and a first treatment module and a second treatment module are fixedly connected to the lower end of the cover plate. By arranging the first treatment module and the second treatment module, the present invention can effectively denitrify wastewater under the combined action of activated sludge and MABR membrane components.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and particularly to a multi-stage AO improved high-efficiency denitrification control device and method based on MABR. Background Art

[0002] Membrane aerated bioreactor (MABR) is a new type of biofilm combined process. Among them, the "membrane" usually selects hollow fiber membrane, and its shape can be flexibly changed; the surface of the hollow fiber membrane is covered with a biofilm, and the outer side of the biofilm is a liquid phase composed of wastewater to be treated. The surface of the hollow fiber membrane not only provides aeration but also serves as a carrier for the biofilm; in actual use, oxygen diffuses into the biofilm through the hollow fiber membrane / biofilm interface, so that the biofilm forms an aerobic layer, a facultative anaerobic layer and an anaerobic layer from the inside to the outside, and the pollutants in the wastewater enter the biofilm reversely through the biofilm / liquid interface, forming an A2O reaction system, which overcomes the problems of poor carrier performance, small specific surface area and easy biofilm shedding of traditional biological filters, greatly improves the oxygen transfer efficiency, and achieves the effect of energy saving and consumption reduction.

[0003] During the wastewater treatment process, the membrane aerated bioreactor and activated sludge are often combined to form a treatment module, and multiple groups of treatment modules are generally set in the treatment system. During the wastewater treatment process, the pollutant content in the wastewater gradually decreases, and the consumption degree of the treatment module that first contacts the wastewater is greater than that of the treatment module that later contacts the wastewater. Therefore, the replacement cycle of the treatment module that first contacts the wastewater is short, and the replacement cycle of the treatment module that later contacts the wastewater is longer than that of the treatment module that first contacts the wastewater. Due to the different replacement cycles of the treatment modules for wastewater treatment, the device is troublesome to use, resulting in an increase in the total number of times of replacing the treatment modules, and increasing the workload of the staff. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a control device and method for upgrading and transforming the traditional multi-stage AO treatment process through MABR membrane components, which can achieve high-efficiency denitrification, reduce aeration energy consumption and treatment costs at the same time, improve the maintenance cycle of the device, and reduce the workload of the staff.

[0005] In order to achieve the above object, the technical solution provided by the present invention is:

[0006] A multi-stage AO improved high-efficiency denitrification control device based on MABR, comprising an anaerobic tank (36), an anoxic tank (32), an aerobic-anoxic tank (35) and an aerobic tank (1) connected in sequence through pipelines. A stirring device is provided in the anoxic tank (32). A cross plate (2) is fixedly connected inside the aerobic tank (1). The top of the cross plate (2) is provided with a first notch (3), a second notch (4), a third notch (5) and a fourth notch (6). A first partition plate (7), a second partition plate (8), a third partition plate (9) and a fourth partition plate (10) are fixedly connected inside the aerobic tank (1). The bottom end of the first partition plate (7) is fixedly connected to the bottom end of the aerobic tank (1). There are gaps between the second partition plate (8), the third partition plate (9), the fourth partition plate (10) and the bottom end of the aerobic tank (1). The cross plate (2), the first partition plate (7), the second partition plate (8), the third partition plate (9) and the fourth partition plate (10) divide the interior of the aerobic tank (1) into multiple cavities. A lifting and rotating device is arranged at the center of the cross plate (2). The lifting and rotating device is connected to a cover plate (25). A first treatment module and a second treatment module are fixedly connected to the lower end of the cover plate (25). The first treatment module and the second treatment module are located in the cavities below them. The first treatment module and the second treatment module are centrosymmetric about the axis center of the cross plate (2).

[0007] Specifically, the cross plate (2), the first partition plate (7), the second partition plate (8), the third partition plate (9) and the fourth partition plate (10) divide the interior of the aerobic tank (1) into a first cavity (11), a second cavity (12), a third cavity (13), a fourth cavity (14), a fifth cavity (15), a sixth cavity (16), a seventh cavity (17) and an eighth cavity (18).

[0008] Specifically, the first treatment module includes a first MABR membrane module (26), a first three-phase separator (27) and a first container (28). The inside of the first container (28) is filled with activated sludge. The first container (28) allows wastewater to pass through and contact the activated sludge inside it. The first MABR membrane module (26) is located in the first cavity (11), and the first three-phase separator (27) and the first container (28) are located in the third cavity (13).

[0009] Specifically, the second treatment module includes a second MABR membrane module (29), a second three-phase separator (30) and a second container (31). The inside of the second container (31) is filled with activated sludge. The second container (31) allows wastewater to pass through and contact the activated sludge inside it. The second MABR membrane module (29) is located in the fifth cavity (15), and the second three-phase separator (30) and the second container (31) are located in the seventh cavity (17).

[0010] Specifically, the lifting and rotating device includes a vertically arranged cylinder (23). The upper end of the telescopic rod of the cylinder (23) is fixed with a motor (24), and the output shaft of the motor (24) is fixedly connected to the cover plate (25).

[0011] Specifically, a first aerator (19) and a second aerator (20) are installed at the inner bottom end of the aerobic tank (1). The first aerator (19) is located in the first cavity (11), and the second aerator (20) is located in the fifth cavity (15).

[0012] Specifically, a liquid inlet pipe (33) is fixedly connected to one side of the anaerobic tank (36). The anaerobic tank (36) is connected to the anoxic tank (32) through a connecting pipe (37), and the anoxic tank (32) and the facultative anaerobic tank (35) are connected through a connecting pipe (38). A connecting pipe (21) and a drain pipe (22) are installed on the aerobic tank (1). One end of the connecting pipe (21) communicates with the first cavity (11), the other end of the connecting pipe (21) communicates with the facultative anaerobic tank (35), the drain pipe (22) communicates with the eighth cavity (18), and the drain pipe (22) is communicated with the connecting pipe (37) through a reflux pipe (34). Valves are installed on the connecting pipe (21), the reflux pipe (34), the connecting pipe (37), and the connecting pipe (38).

[0013] Specifically, the depths of the first notch (3), the second notch (4), the third notch (5), and the fourth notch (6) increase in sequence and form an arithmetic progression.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] 1. By arranging the first treatment module and the second treatment module, the present invention can perform deep denitrification treatment on wastewater under the combined action of the MABR membrane module and activated sludge, improve the treatment efficiency of the traditional multi-stage AO treatment process, and reduce its energy consumption level.

[0016] 2. After the wastewater is treated for a period of time, by swapping the positions of the first treatment module and the second treatment module, the second treatment module first comes into contact with the wastewater together with the first treatment module. After treating the wastewater for a certain period of time later, it can be ensured that the consumption degrees of the first treatment module and the second treatment module are similar, and when the first treatment module and the second treatment module are replaced simultaneously, the waste caused by the low consumption degree of the second treatment module will not occur.

[0017] 3. By swapping the positions of the first treatment module and the second treatment module, the cycle of replacing the MABR membrane module and activated sludge can be increased on the premise of ensuring the effective treatment of wastewater, and the maintenance cost of the device can be reduced. Description of the Drawings

[0018] Figure 1 This is a perspective view of the multi-stage AO improved high-efficiency denitrification control device based on MABR of the present invention;

[0019] Figure 2 This is a schematic structural diagram of the multi-stage AO improved high-efficiency denitrification control device based on MABR of the present invention;

[0020] Figure 3 This is a schematic view of the aerobic tank;

[0021] Figure 4 This is a schematic internal structure diagram of the aerobic tank;

[0022] Figure 5 This is a schematic view of the internal cavity of the aerobic tank;

[0023] Figure 6 This is a sectional view of the aerobic tank;

[0024] Figure 7 This is a schematic view of the cooperation of the first treatment module and the second treatment module with the cover plate.

[0025] The names of the components in the drawings are:

[0026] 1. Aerobic tank; 2. Cross plate; 3. First notch; 4. Second notch; 5. Third notch; 6. Fourth notch; 7. First partition; 8. Second partition; 9. Third partition; 10. Fourth partition; 11. First cavity; 12. Second cavity; 13. Third cavity; 14. Fourth cavity; 15. Fifth cavity; 16. Sixth cavity; 17. Seventh cavity; 18. Eighth cavity; 19. First aerator; 20. Second aerator; 21. Connecting pipe; 22. Drain pipe; 23. Cylinder; 24. Motor; 25. Cover plate; 26. First MABR membrane module; 27. First three-phase separator; 28. First container; 29. Second MABR membrane module; 30. Second three-phase separator; 31. Second container; 32. Anoxic tank; 33. Inlet pipe; 34. Return pipe; 35. Facultative oxygen tank; 36. Anaerobic tank; 37. Connecting pipe; 38. Connecting pipe. Detailed implementation mode

[0027] As Figures 1-6 shown, a multi-stage AO improved high-efficiency denitrification control device based on MABR includes an anaerobic tank 36, an anoxic tank 32, a facultative oxygen tank 35 and an aerobic tank 1 that are sequentially connected through pipelines, and a stirring device is installed in the anoxic tank 32.

[0028] The cross plate 2 is fixedly connected inside the aerobic tank 1, and the first notch 3, the second notch 4, the third notch 5 and the fourth notch 6 are opened at the top of the cross plate 2. The depths of the first notch 3, the second notch 4, the third notch 5 and the fourth notch 6 increase in sequence and show an arithmetic progression relationship.

[0029] Inside the aerobic tank 1, a first partition plate 7, a second partition plate 8, a third partition plate 9 and a fourth partition plate 10 are fixedly connected. The bottom end of the first partition plate 7 is fixedly connected to the bottom end of the aerobic tank 1. There are gaps between the second partition plate 8, the third partition plate 9, the fourth partition plate 10 and the bottom end of the aerobic tank 1 respectively. The cross plate 2, the first partition plate 7, the second partition plate 8, the third partition plate 9 and the fourth partition plate 10 divide the inside of the aerobic tank 1 into a first cavity 11, a second cavity 12, a third cavity 13, a fourth cavity 14, a fifth cavity 15, a sixth cavity 16, a seventh cavity 17 and an eighth cavity 18.

[0030] The first treatment module includes a first MABR membrane module 26, a first three-phase separator 27 and a first container 28. The inside of the first container 28 is filled with activated sludge, and the first container 28 allows wastewater to pass through and contact the activated sludge inside. The first MABR membrane module 26 is located in the first cavity 11. The first three-phase separator 27 and the first container 28 are located in the third cavity 13.

[0031] The second treatment module includes a second MABR membrane module 29, a second three-phase separator 30 and a second container 31. The inside of the second container 31 is filled with activated sludge, and the second container 31 allows wastewater to pass through and contact the activated sludge inside. The second MABR membrane module 29 is located in the fifth cavity 15. The second three-phase separator 30 and the second container 31 are located in the seventh cavity 17.

[0032] Functional bacteria AOB and NOB are distributed in the aerobic tank 1. Under the action of AOB, ammonia nitrogen NH4 + is oxidized to nitrite nitrogen NO2 ― , and under the action of NOB, nitrite nitrogen NO2 ― is oxidized to nitrate nitrogen NO3 ― . By appropriately controlling the structural composition and spatial distribution of the AOB and NOB bacterial communities, the competitive advantages of the two populations are regulated to achieve short-cut nitrification and denitrification.

[0033] A lifting and rotating device is arranged at the center of the cross plate 2. The lifting and rotating device is connected to the cover plate 25. The lower end of the cover plate 25 is fixedly connected with a first treatment module and a second treatment module. The first treatment module and the second treatment module are located in the cavity below them. The first treatment module and the second treatment module are centrosymmetric about the axis center of the cross plate 2.

[0034] The lifting and rotating device includes a vertically arranged cylinder 23. The upper end of the telescopic rod of the cylinder 23 is fixed with a motor 24. The output shaft of the motor 24 is fixedly connected to the cover plate 25.

[0035] At the inner bottom end of the aerobic tank 1, a first aerator 19 and a second aerator 20 are installed. The first aerator 19 is located within the first cavity 11. The second aerator 20 is located within the fifth cavity 15.

[0036] One side of the anaerobic tank 36 is fixedly connected to a liquid inlet pipe 33. The anaerobic tank 36 is connected to the anoxic tank 32 through a connecting pipe 37. The anoxic tank 32 and the facultative tank 35 are connected through a connecting pipe 38. A connecting pipe 21 and a drain pipe 22 are installed on the aerobic tank 1. One end of the connecting pipe 21 communicates with the first cavity 11, and the other end of the connecting pipe 21 communicates with the facultative tank 35. The drain pipe 22 communicates with the eighth cavity 18, and the drain pipe 22 is communicated with the connecting pipe 37 through a reflux pipe 34. Valves are installed on the connecting pipe 21, the reflux pipe 34, the connecting pipe 37, and the connecting pipe 38.

[0037] When treating wastewater, the wastewater enters the anaerobic tank 36 through the liquid inlet pipe 33, and the high-COD substances are partially decomposed in the anaerobic tank 36; then it enters the anoxic tank 32 through the connecting pipe 37 for denitrification; then it enters the facultative tank 35 through the connecting pipe 38. The facultative tank 35 is a sewage purification tank with both anaerobic and aerobic microorganisms; then it enters the aerobic tank 1 through the connecting pipe 21 for the oxidative degradation and nitrification of organic matter.

[0038] When the wastewater enters the aerobic tank 1, the first aerator 19 and the second aerator 20 are started, and the wastewater is discharged into the first cavity 11 through the connecting pipe 21. The water level in the first cavity 11 gradually rises, and the wastewater can be treated under the action of the first aerator 19 and the first MABR membrane module 26.

[0039] When the water level in the first cavity 11 is higher than the first notch 3, the water in the first cavity 11 will enter the second cavity 12 through the first notch 3. Since the bottoms of the second cavity 12 and the third cavity 13 are in a communicating state, the wastewater will enter the third cavity 13 from the second cavity 12. When the water passes through the first container 28, the activated sludge inside the first container 28 can treat the wastewater. When the wastewater passes through the first three-phase separator 27, the bubbles and a small amount of activated sludge in the wastewater can be removed.

[0040] When the water level in the third cavity 13 is higher than the second notch 4, the water in the third cavity 13 will enter the fourth cavity 14 through the second notch 4. The bottoms of the fourth cavity 14 and the fifth cavity 15 are in a communicating state, and the wastewater will enter the fifth cavity 15 from the fourth cavity 14. As the water level in the fifth cavity 15 gradually rises, the wastewater is treated under the action of the second aerator 20 and the second MABR membrane module 29.

[0041] When the water level in the fifth cavity 15 is higher than the third notch 5, the wastewater in the fifth cavity 15 will enter the sixth cavity 16 through the third notch 5. The bottoms of the sixth cavity 16 and the seventh cavity 17 are in a communicating state, so the wastewater will enter the seventh cavity 17 from the sixth cavity 16. When the wastewater passes through the second container 31, the activated sludge inside the second container 31 can treat the wastewater. Then, when passing through the second three-phase separator 30, the bubbles and a small amount of activated sludge in the water can be removed.

[0042] When the water level in the seventh cavity 17 is higher than the fourth notch 6, at this time, the wastewater in the seventh cavity 17 will enter the eighth cavity 18 through the fourth notch 6 and be discharged from the drain pipe 22.

[0043] The valve on the reflux pipe 34 is opened, so that a part of the effluent discharged from the drain pipe 22 flows back through the reflux pipe 34, mixes with the effluent of the anaerobic tank 36 and enters the anoxic tank 32, making full use of the carbon source in the wastewater to ensure the efficiency of denitrification.

[0044] After treating the wastewater for a certain period of time, the telescopic rod of the cylinder 23 moves upward, causing the motor 24, the cover plate 25, the first MABR membrane module 26, the first container 28, the first three-phase separator 27, the second MABR membrane module 29, the second container 31 and the second three-phase separator 30 to move upward. Then control the output shaft of the motor 24 to drive the cover plate 25, the first MABR membrane module 26, the first container 28, the first three-phase separator 27, the second MABR membrane module 29, the second container 31 and the second three-phase separator 30 to rotate 180 degrees. At this time, the first MABR membrane module 26 corresponds to the fifth cavity 15, the first three-phase separator 27 and the first container 28 correspond to the seventh cavity 17, the second MABR membrane module 29 is located corresponding to the first cavity 11, and the second three-phase separator 30 and the second container 31 correspond to the third cavity 13. Then control the telescopic rod of the cylinder 23 to contract and return to its original position, so that the first MABR membrane module 26 enters the fifth cavity 15. The first three-phase separator 27 and the first container 28 enter the seventh cavity 17. The second MABR membrane module 29 enters the first cavity 11. The second three-phase separator 30 and the second container 31 enter the third cavity 13.

[0045] During the process of the wastewater flowing through the first treatment module and the second treatment module, the amount of pollutants in the wastewater in contact with the first treatment module is greater than that in the wastewater in contact with the second treatment module. The consumption degree of the first treatment module is greater than that of the second treatment module. After swapping the positions of the first treatment module and the second treatment module, the second treatment module first contacts the wastewater with the first treatment module, and after treating the wastewater for a certain period of time subsequently, it can ensure that the consumption degrees of the first treatment module and the second treatment module are similar. When replacing the first treatment module and the second treatment module simultaneously, it will not cause waste due to the low consumption degree of the second treatment module.

[0046] By swapping the positions of the first treatment module and the second treatment module, it is possible to increase the replacement cycle of the first treatment module and the second treatment module on the premise of ensuring the effective treatment of the wastewater, and it can reduce the maintenance cost of the device.

[0047] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multi-stage AO improved high-efficiency denitrification control device based on MABR, comprising an anaerobic tank (36), an anoxic tank (32), an aerobic-anoxic tank (35) and an aerobic tank (1) which are sequentially connected through pipelines, and a stirring device is arranged in the anoxic tank (32), and is characterized in that, Inside the aerobic tank (1), a cross plate (2) is fixedly connected. At the top of the cross plate (2), a first notch (3), a second notch (4), a third notch (5), and a fourth notch (6) are provided. Inside the aerobic tank (1), a first partition plate (7), a second partition plate (8), a third partition plate (9), and a fourth partition plate (10) are fixedly connected. Among them, the bottom end of the first partition plate (7) is fixedly connected to the bottom end of the aerobic tank (1), and there are gaps between the bottom ends of the second partition plate (8), the third partition plate (9), and the fourth partition plate (10) and the bottom end of the aerobic tank (1). The cross plate (2), the first partition plate (7), the second partition plate (8), the third partition plate (9), and the fourth partition plate (10) divide the interior of the aerobic tank (1) into multiple cavities. A lifting and rotating device is arranged at the center of the cross plate (2), and the lifting and rotating device is connected to the cover plate (25). At the lower end of the cover plate (25), a first treatment module and a second treatment module are fixedly connected. The first treatment module and the second treatment module are located in the cavities below them, and the first treatment module and the second treatment module are centrosymmetric with respect to the axis center of the cross plate (2); the cross plate (2), the first partition plate (7), the second partition plate (8), the third partition plate (9), and the fourth partition plate (10) divide the interior of the aerobic tank (1) into a first cavity (11), a second cavity (12), a third cavity (13), a fourth cavity (14), a fifth cavity (15), a sixth cavity (16), a seventh cavity (17), and an eighth cavity (18); the first treatment module includes a first MABR membrane module (26), a first three-phase separator (27), and a first container (28). The inside of the first container (28) is filled with activated sludge. The first container (28) allows wastewater to pass through and contact the activated sludge inside it. The first MABR membrane module (26) is located in the first cavity (11), and the first three-phase separator (27) and the first container (28) are located in the third cavity (13); the second treatment module includes a second MABR membrane module (29), a second three-phase separator (30), and a second container (31). The inside of the second container (31) is filled with activated sludge. The second container (31) allows wastewater to pass through and contact the activated sludge inside it. The second MABR membrane module (29) is located in the fifth cavity (15), and the second three-phase separator (30) and the second container (31) are located in the seventh cavity (17); the lifting and rotating device includes a vertically arranged cylinder (23). The upper end of the telescopic rod of the cylinder (23) is fixed with a motor (24), and the output shaft of the motor (24) is fixedly connected to the cover plate (25); the depths of the first notch (3), the second notch (4), the third notch (5), and the fourth notch (6) increase in sequence and form an arithmetic progression.

2. The multi-stage AO improved high-efficiency denitrification control device based on MABR according to claim 1, characterized in that, At the inner bottom end of the aerobic tank (1), a first aerator (19) and a second aerator (20) are installed. The first aerator (19) is located in the first cavity (11), and the second aerator (20) is located in the fifth cavity (15).

3. The multi-stage AO improved high-efficiency denitrification control device based on MABR according to claim 1, characterized in that, One side of the anaerobic tank (36) is fixedly connected to a liquid inlet pipe (33). The anaerobic tank (36) is connected to the anoxic tank (32) through a connecting pipe (37). The anoxic tank (32) and the facultative anaerobic tank (35) are connected through a connecting pipe (38). A connecting pipe (21) and a drain pipe (22) are installed on the aerobic tank (1). One end of the connecting pipe (21) communicates with the first cavity (11), and the other end of the connecting pipe (21) communicates with the facultative anaerobic tank (35). The drain pipe (22) communicates with the eighth cavity (18). The drain pipe (22) is communicated with the connecting pipe (37) through a reflux pipe (34). Valves are installed on the connecting pipe (21), the reflux pipe (34), the connecting pipe (37), and the connecting pipe (38).

4. A multi-stage AO improved high-efficiency denitrification control method based on MABR, characterized in that Using the control device according to any one of claims 1-3, the method includes the following steps: wastewater enters the anaerobic tank (36), enabling partial decomposition of high-COD substances in the anaerobic tank (36), then enters the anoxic tank (32) for denitrification, and then sequentially enters the facultative anaerobic tank (35) and the aerobic tank (1) for oxidative degradation and nitrification of organic matter; the wastewater successively enters the multiple cavities formed by partitioning inside the aerobic tank (1) through the first notch (3), the gap at the bottom of the second partition (8), the second notch (4), the gap at the bottom of the third partition (9), the third notch (5), the gap at the bottom of the fourth partition (10), and the fourth notch (6) until it is discharged; a part of the discharged effluent is refluxed, mixed with the effluent from the anaerobic tank (36), and enters the anoxic tank (32) to make full use of the carbon source in the wastewater to ensure the efficiency of denitrification; after the wastewater is treated for a certain period of time, the lifting and rotating device drives the cover plate (25) to rise, and rotates and positions the first treatment module and the second treatment module. Then, the lifting and rotating device drives the cover plate (25) to descend, and the first treatment module and the second treatment module fall into the cavity after their positions are exchanged.

Images