Denitrification strengthening device based on AOA process coupled MABR membrane

Abstract

The utility model relates to a denitrification strengthening device based on AOA process coupling MABR membrane, which comprises a water distribution system, a biological reaction system and a sedimentation tank, the water distribution system comprises a water inlet pipeline, and the water inlet pipeline is provided with two branches, namely a water distribution pipeline I and a water distribution pipeline II; the water distribution pipeline I and the water distribution pipeline II are both connected with the biological reaction system; the biological reaction system comprises an anaerobic tank, an aerobic tank and an MABR membrane tank which are communicated in sequence, and an MABR membrane assembly is arranged in the MABR membrane tank; the MABR membrane tank is communicated with the sedimentation tank, the sedimentation tank is provided with a sludge return pipe which is connected to the front end of the anaerobic tank, and the sedimentation tank is also provided with a water outlet pipeline and a sludge discharge pipeline. The AOA process is coupled with the MABR membrane, so that the occupied area and the use amount of the MABR membrane are reduced, the two denitrification processes are superposed, the denitrification effect of sewage treatment is enhanced, and the denitrification efficiency is improved by more than 30%; the anoxic tank part of the AOA process is provided with the MABR membrane tank, and the MABR membrane tank can be used for synchronously carrying out denitrification and nitrification and denitrification under the condition of low carbon nitrogen ratio, so that efficient denitrification is realized.

Description

Technical Field

[0001] This utility model belongs to the field of wastewater treatment technology, specifically relating to a denitrification enhancement device based on AOA process coupled with MABR membrane. Background Technology

[0002] With rapid urbanization and increasingly stringent environmental protection requirements, urban wastewater treatment plants in my country are generally facing a contradiction between the need for stricter nitrogen and phosphorus discharge standards (such as Class A standards and near-Class IV water quality) and insufficient treatment efficiency. This contradiction is particularly prominent in northern regions. Current mainstream processes such as AAO (anaerobic-anoxic-aerobic), AO (anoxic-aerobic), and oxidation ditches have revealed a vicious cycle in nitrogen removal during long-term operation: "carbon source competition → functional bacterial community inhibition → low reaction efficiency → rising operating costs." These processes are unable to meet the stable compliance requirements of the Class A standard of the "Discharge Standard of Pollutants for Urban Wastewater Treatment Plants" (GB18918-2002), and are even less able to adapt to the increasingly stringent near-Class IV water quality discharge requirements.

[0003] In recent years, the industry has attempted to optimize the denitrification pathway through modified AAO (such as inverted AAO, AOA) and multi-stage AO series connection. Although some results have been achieved, the fundamental contradiction between carbon source distribution and dissolved oxygen control has not been overcome.

[0004] In wastewater treatment, there are currently two types of commonly used MABR (membrane biofilm reactor) on the market: microporous membranes, which are inexpensive but suffer from fouling problems, and non-porous membranes, which are expensive but largely solve the fouling problem. Although MABR technology has the potential for simultaneous nitrification and denitrification, regardless of which type of MABR membrane is used to directly replace traditional processes, there are still industrialization obstacles such as easy clogging of microporous biofilms and high investment costs for large-scale use. Utility Model Content

[0005] The purpose of this utility model is to solve the above-mentioned problems. This application proposes a denitrification enhancement device based on AOA process coupled with MABR membrane, which combines the traditional AOA process with MABR membrane tank, and the MABR membrane module adopts a dense and non-porous membrane module, which solves the problems of easy fouling and high cost when the membrane process is used in large quantities.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a denitrification enhancement device based on AOA process coupled with MABR membrane, comprising a water distribution system, a biological reaction system, and a sedimentation tank, wherein the water distribution system includes an inlet pipe, and the inlet pipe has two branches, water distribution pipe I and water distribution pipe II; both water distribution pipe I and water distribution pipe II are connected to the biological reaction system;

[0007] The bioreactor system includes an anaerobic tank, an aerobic tank, and an MABR membrane tank connected in sequence, and the MABR membrane tank is equipped with a MABR membrane module.

[0008] The MABR membrane tank is connected to the sedimentation tank. The sedimentation tank is equipped with a sludge return pipe that connects to the front end of the anaerobic tank. The sedimentation tank is also equipped with an effluent pipe and a sludge discharge pipe.

[0009] Furthermore: the water distribution pipe I is connected to the anaerobic tank, and the water distribution pipe II is connected to the MABR membrane tank.

[0010] Furthermore: the influent to the MABR membrane tank includes wastewater transported by water distribution pipe II and a mixed liquor from the aerobic tank, with the wastewater transported by water distribution pipe II accounting for 10% to 30%.

[0011] Furthermore: the sludge return pipe returns the sludge from the sedimentation tank to the front end of the anaerobic tank, with a return flow rate of 20-100%.

[0012] Furthermore: The MABR membrane module is a dense, non-porous type. During the wastewater treatment process, oxygen diffuses to the outer layer through bubble-free transport. The large amount of biofilm attached to the surface of the MABR membrane module forms a layered structure of aerobic-anoxic-anaerobic from the inside out, allowing nitrifying bacteria and denitrifying bacteria to carry out nitrification and denitrification in separate zones.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0014] This invention couples the AOA process with a MABR membrane, reducing the floor space and the amount of MABR membrane used. The superposition of the two denitrification processes enhances the denitrification effect in wastewater treatment, increasing the denitrification efficiency by more than 30%. A MABR membrane tank is set in the anoxic tank section of the AOA process. The MABR membrane module can be used to simultaneously carry out denitrification and nitrification / denitrification under low carbon-to-nitrogen ratio conditions, achieving highly efficient denitrification.

[0015] The water distribution system has two inlet pipes. One of them, water distribution pipe II, transports a certain proportion of wastewater as a carbon source to the MABR membrane tank. This ensures that there is sufficient carbon source for denitrification and that other pollutants (such as BOD5 and ammonia nitrogen) are removed simultaneously in the MABR membrane tank.

[0016] This invention achieves efficient denitrification with no or only a small amount of carbon source. It couples traditional processes with MABR membrane processes, reduces the internal reflux system, and has lower energy consumption. It adopts a dense, non-porous MABR membrane module, which solves the contradiction between fouling in microporous membranes and high cost when using a large number of non-porous membranes. Compared with general MABR membrane processes, the cost is reduced by 20% to 40%. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only for more clearly illustrating the technical solutions in the embodiments of this utility model or the prior art. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0019] In the diagram: 1-Inlet pipe, 2-Distribution pipe I, 3-Distribution pipe II, 4-Anaerobic tank, 5-Aerobic tank, 6-MABR membrane tank, 7-Sedimentation tank, 8-Sludge return pipe, 9-Sludge discharge pipe, 10-Effluent pipe, 11-MABR membrane module. Detailed Implementation

[0020] To enable those skilled in the art to better understand and implement the technical solution of this utility model, the present utility model will be further described below with reference to specific embodiments. However, the embodiments described are only for illustration and are not intended to limit the present utility model.

[0021] like Figure 1 The nitrogen removal enhancement device based on AOA process coupled with MABR membrane is shown. It includes an inlet pipe 1, which is divided into two branches, namely a distribution pipe I2 and a distribution pipe II3. The distribution pipe I2 is connected to an anaerobic tank 4, and the distribution pipe II3 is connected to a MABR membrane tank 6. The anaerobic tank 4 is connected to an aerobic tank 5, and the aerobic tank 5 is connected to the MABR membrane tank 6. The MABR membrane tank 6 is equipped with a MABR membrane module 11. The MABR membrane module 11 is a dense, non-porous MABR membrane module. The influent of the MABR membrane tank 6 includes wastewater transported by the distribution pipe II3 and a mixed liquor from the aerobic tank 5. The wastewater transported by the distribution pipe II3 accounts for 10% to 30%, and the hydraulic retention time in the MABR membrane tank is 4 to 8 hours.

[0022] The hydraulic retention time of wastewater in anaerobic tank 4 is 1-2 hours, and the hydraulic retention time in aerobic tank 5 is 3-8 hours.

[0023] The MABR membrane tank 6 is connected to the sedimentation tank 7, which plays a role in separating sludge and water. The sedimentation tank 7 is equipped with a sludge return pipe 8 connected to the front end of the anaerobic tank 4 to return the sludge from the sedimentation tank 7 to the anaerobic tank 4. The sedimentation tank 7 is also equipped with an effluent pipe 10 and a sludge discharge pipe 9. The clean water is discharged through the effluent pipe 10, and the remaining sludge is discharged through the sludge discharge pipe 9.

[0024] Because the MABR membrane tank uses a dense, non-porous MABR membrane module, oxygen diffuses to the outer layer through bubble-free transport, achieving an oxygen utilization efficiency of over 60%. The large amount of biofilm attached to the surface of the dense, non-porous MABR membrane module forms a layered structure of aerobic-anoxic-anaerobic from the inside out. This layered structure promotes the enrichment of nitrifying and denitrifying bacteria in their respective suitable areas, forming a stable functional division of labor and improving nitrogen removal efficiency.

[0025] All content not described in detail in this utility model is prior art.

[0026] It should be noted that the above description describes the structure of the denitrification enhancement device of this application. Without departing from the technical principles of this application, those skilled in the art can combine the technical solutions in the above embodiments, or make equivalent changes or substitutions to the relevant technical features. Any changes or equivalent substitutions made within the technical concept and / or technical principles of this application will fall within the protection scope of this application.

Claims

1. A denitrification enhancement device based on AOA process coupled with MABR membrane, comprising a water distribution system, a biological reaction system, and a sedimentation tank, characterized in that: The water distribution system includes an inlet pipe (1), which has two branches: a water distribution pipe I (2) and a water distribution pipe II (3); both the water distribution pipe I (2) and the water distribution pipe II (3) are connected to the bioreactor system. The bioreactor system includes an anaerobic tank (4), an aerobic tank (5), and a MABR membrane tank (6) connected in sequence. The MABR membrane tank (6) is equipped with a MABR membrane module (11). The MABR membrane tank (6) is connected to the sedimentation tank (7). The sedimentation tank (7) is provided with a sludge return pipe (8) connected to the front end of the anaerobic tank (4). The sedimentation tank (7) is also provided with an effluent pipe (10) and a sludge discharge pipe (9).

2. The denitrification enhancement device based on AOA process coupled with MABR membrane according to claim 1, characterized in that: The water distribution pipe I (2) is connected to the anaerobic tank (4), and the water distribution pipe II (3) is connected to the MABR membrane tank (6).

3. The denitrification enhancement device based on AOA process coupled with MABR membrane according to claim 1, characterized in that: The influent to the MABR membrane tank (6) includes wastewater transported by the water distribution pipe II (3) and the mixed liquor in the aerobic tank (5), with the wastewater transported by the water distribution pipe II (3) accounting for 10% to 30%.

4. The denitrification enhancement device based on AOA process coupled with MABR membrane according to claim 1, characterized in that: The sludge return pipe (8) returns the sludge from the sedimentation tank (7) to the front end of the anaerobic tank (4) with a return flow rate of 20-100%.

5. The denitrification enhancement device based on AOA process coupled with MABR membrane according to claim 1, characterized in that: The MABR membrane module (11) is a dense, non-porous MABR membrane module.

Images