AAO + MBR sewage purification system

Abstract

According to the technical scheme, the AAO + MBR sewage purification system is characterized in that the AAO + MBR sewage purification system comprises a membrane grid, and the membrane grid is connected with a water inlet pipe to block particles and microorganisms in sewage to achieve preliminary filtration of the sewage; the number of the biological reaction areas is at least one, and at least an aerobic environment and an anaerobic environment are built in the biological reaction areas; the membrane tank is connected with the water outlet pipe, the water inlet end of the biological reaction area is connected with the membrane grid, and the water outlet end of the biological reaction area is connected with the membrane tank; the biological reaction zone comprises an aerobic zone, and a plurality of aeration pipes which are independently controlled along the water flowing direction are arranged in the aerobic zone; the aeration pipe in the aerobic zone is independently arranged, so that the concentration of dissolved oxygen in each section in the aerobic zone can be controlled, the TN removal efficiency is improved, and the content of DO in sewage is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage purification, and more particularly to an AAO+MBR sewage purification system. Background Art

[0002] AAO+MBR process is a very common treatment process in sewage treatment. The biggest feature of AAO+MBR process is that it can completely separate the water residence time and sludge age in the bioreactor, and ensure a very high sludge age under a shorter residence time. The sludge concentration can be as high as 8-10g / L, which is 2-3 times that of ordinary activated sludge method, which creates favorable conditions for the degradation of organic pollutants and nitrogen pollutants.

[0003] However, with the gradual extension of operation, the problems of low TN (total nitrogen) removal efficiency and high energy consumption of the AAO+MBR process have become increasingly prominent, and the DO (dissolved oxygen) content in the sewage treatment process is relatively high. Now it is urgent to transform the AAO+MBR process to solve the above problems. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide an AAO+MBR sewage purification system, which can control the dissolved oxygen concentration in each section of the aerobic zone by separately setting the aeration pipe in the aerobic zone, thereby improving the TN removal efficiency and reducing the DO content in the sewage.

[0005] To achieve the above object, the present invention provides the following technical solution: an AAO+MBR sewage purification system, comprising a membrane grid, wherein the membrane grid is connected to a water inlet pipe to block particles and microorganisms in the sewage to achieve preliminary filtration of the sewage; A biological reaction zone, wherein at least one biological reaction zone is provided, and the biological reaction zone at least creates an aerobic environment and an anaerobic environment; and a membrane pool, wherein the membrane pool is connected to the water outlet pipe, the water inlet end of the biological reaction zone is connected to the membrane grid, and the water outlet end is connected to the membrane pool; The biological reaction zone includes an aerobic zone, in which a plurality of aeration pipes which are individually controlled along the water flow direction are arranged.

[0006] The present invention is further configured as follows: the biological reaction zone further comprises an anaerobic zone, and the anaerobic zone is connected to the membrane grid; and an anoxic zone, wherein the anoxic zone is disposed between the anaerobic zone and the aerobic zone.

[0007] The present invention is further configured as follows: the aerobic zone is divided into a first aerobic zone and a second aerobic zone, and the first aerobic zone and the second aerobic zone are arranged in sequence according to the flow direction of the sewage.

[0008] The present invention is further configured such that the aeration pipe located at the end of the sewage flow in the second aerobic zone is in a closed state.

[0009] The present invention is further configured to include a post-anoxic zone, wherein the post-anoxic zone is arranged between the second aerobic zone and the membrane pool.

[0010] The present invention is further configured as follows: it also includes a reaction tank, the membrane grid is arranged at the water inlet end of the reaction tank, the membrane tank is arranged at the water outlet end of the reaction tank, and the water inlet end and the water outlet end of the reaction tank are arranged oppositely; There are two biological reaction zones, which are respectively arranged on both sides of the center line of the reaction pool.

[0011] The present invention is further configured as follows: the membrane grid is arranged in the middle of the water inlet end of the reaction tank, and the two anaerobic zones of the two biological reaction zones are arranged on both sides of the membrane grid respectively; The anoxic zones of the two biological reaction zones are respectively arranged on both sides of the reaction tank and one end of the biological reaction zone close to the anaerobic zone is connected to the anaerobic zone; The side where the two anaerobic zones are close to each other is set as the first aerobic zone, the side where the two first aerobic zones are close to each other is set as the second aerobic zone, and the end of the second aerobic zone close to the membrane tank is set as the post-anoxic zone.

[0012] The present invention is further configured as follows: one end of the first aerobic zone close to the membrane grid is connected to the second aerobic zone; An alternating zone is arranged at one end of the first aerobic zone close to the membrane tank, and the alternating zone is communicated with the anoxic zone.

[0013] The present invention is further configured as follows: the reflux ratio from the anoxic zone to the anaerobic zone is set to 200%; the reflux ratio from the aerobic zone to the anoxic zone is 200%, and the reflux ratio of the membrane pool is set to 400%.

[0014] The present invention is further configured as follows: the carbon source addition position is arranged at one end of the anoxic zone close to the anaerobic zone, and the iron salt addition position is arranged at a position of the first aerobic zone close to the second aerobic zone.

[0015] In summary, compared with the prior art, the present invention has the following beneficial effects: by separately setting aeration pipes in the aerobic zone, the present invention can control the dissolved oxygen concentration in each section of the aerobic zone, thereby improving the TN removal efficiency and reducing the DO content in the sewage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the overall structure of the embodiment.

[0017] In the figure: 1. membrane grid; 2. membrane pool; 3. anaerobic zone; 4. anoxic zone; 5. alternating zone; 6. first aerobic zone; 7. second aerobic zone; 8. post-anoxic zone; 10. reaction tank. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is clearly and completely described below in conjunction with the accompanying drawings of the present invention. Based on the embodiments in this application, other similar embodiments obtained by ordinary technicians in this field without making creative work should all fall within the scope of protection of this application. In addition, the directional words mentioned in the following embodiments, such as "up", "down", "left", "right", etc., are only reference to the directions of the accompanying drawings. Therefore, the directional words used are used to illustrate rather than limit the invention.

[0019] The present invention will be further described below in conjunction with the accompanying drawings and preferred embodiments.

[0020] Example: A AAO+MBR sewage purification system, see attached Figure 1 , including a membrane grid 1, a biological reaction zone and a membrane pool 2, wherein the membrane grid 1 is connected to an inlet pipe to block particles and microorganisms in sewage to achieve preliminary filtration of sewage; the biological reaction zone is provided with at least one, and the biological reaction zone at least creates an aerobic and anaerobic environment; the membrane pool 2 is connected to an outlet pipe, the water inlet end of the biological reaction zone is connected to the membrane grid 1, and the water outlet end is connected to the membrane pool 2; the biological reaction zone includes an aerobic zone, and the aerobic zone is provided with a plurality of aeration pipes that are individually controlled along the water flow direction.

[0021] The biological reaction zone further includes an anaerobic zone 3 and an anoxic zone 4 . The anaerobic zone 3 is connected to the membrane grid 1 . The anoxic zone 4 is arranged between the anaerobic zone 3 and the aerobic zone.

[0022] Specifically, the aerobic zone is divided into a first aerobic zone 6 and a second aerobic zone 7, and the first aerobic zone 6 and the second aerobic zone 7 are arranged in sequence according to the flow direction of the sewage.

[0023] Specifically, the aeration pipe at the end of the sewage flow in the second aerobic zone 7 is in a closed state. When the aeration pipes in the first aerobic zone 6 and the second aerobic zone 7 are both in an open state, it is easy to cause excessive DO content in the sewage in the system, affecting the TN removal efficiency and increasing the cost. When encountering this problem, the aeration pipe at the end of the sewage flow in the second aerobic zone 7 is closed in this embodiment, thereby reducing the DO content of the sewage flowing out of the second aerobic zone 7.

[0024] Specifically, this embodiment further includes a post-anoxic zone 8 , which is disposed between the second aerobic zone 7 and the membrane pool 2 .

[0025] Specifically, this embodiment also includes a reaction tank 10, the membrane grid 1 is arranged at the water inlet end of the reaction tank 10, the membrane tank 2 is arranged at the water outlet end of the reaction tank 10, and the water inlet end and the water outlet end of the reaction tank 10 are arranged opposite to each other; two biological reaction zones are arranged, and the two biological reaction zones are respectively arranged on both sides of the center line of the reaction tank 10.

[0026] The reaction tank 10 provides a carrier for the membrane grid 1 and the biological reaction zone.

[0027] Specifically, the membrane grid 1 is arranged in the middle of the water inlet end of the reaction tank 10, and the two anaerobic zones 3 of the two biological reaction zones are arranged on both sides of the membrane grid 1; the anoxic zones 4 of the two biological reaction zones are arranged on both sides of the reaction tank 10, and the end of the biological reaction zone close to the anaerobic zone 3 is connected with the anaerobic zone 3; the side of the two anaerobic zones 3 close to each other is set as the first aerobic zone 6, the side of the two first aerobic zones 6 close to each other is set as the second aerobic zone 7, and the end of the second aerobic zone 7 close to the membrane tank 2 is set as the post-anoxic zone 8; the end of the first aerobic zone 6 close to the membrane grid 1 is connected with the second aerobic zone 7; the end of the first aerobic zone 6 close to the membrane tank 2 is provided with an alternating zone 5, and the alternating zone 5 is connected with the anoxic zone 4. When the alternating zone 5 adjusts the specific aerobic and anaerobic time of the sewage treatment process according to different sewage batches, the alternating zone 5 can be switched to aerobic and anoxic states at any time.

[0028] Specifically, a plurality of buoy agitators are arranged at the end of the second aerobic zone 7 .

[0029] Specifically, the reflux ratio from the anoxic zone 4 to the anaerobic zone 3 is set to 200%; the reflux ratio from the aerobic zone to the anoxic zone 4 is 200%, and the reflux ratio of the membrane pool 2 is set to 400%.

[0030] Specifically, the carbon source adding position is set at one end of the anoxic zone 4 close to the anaerobic zone 3 , and the iron salt adding position is set at a position of the first aerobic zone 6 close to the second aerobic zone 7 .

[0031] Specifically, in order to reduce the impact of the high DO carried by the reflux of the membrane pool 2 on the aerobic section, the reflux liquid of the membrane pool 2 is refluxed to the front end of the alternating zone 5, and the alternating zone 5 is used as an oxygen elimination zone to further enhance the denitrification function of the system.

[0032] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. An AAO+MBR sewage purification system, characterized by: It comprises a membrane grid (1), wherein the membrane grid (1) is connected to a water inlet pipe to block particles and microorganisms in sewage to achieve preliminary filtration of the sewage; A biological reaction zone, wherein at least one biological reaction zone is provided, and the biological reaction zone at least creates an aerobic environment and an anaerobic environment; and a membrane pool (2), wherein the membrane pool (2) is connected to a water outlet pipe, the water inlet end of the biological reaction zone is connected to the membrane grid (1), and the water outlet end is connected to the membrane pool (2); The biological reaction zone includes an aerobic zone, in which a plurality of aeration pipes which are individually controlled along the water flow direction are arranged.

2. The AAO+MBR sewage purification system according to claim 1, characterized in that: The biological reaction zone also includes an anaerobic zone (3), and the anaerobic zone (3) is connected to the membrane grid (1); and an anoxic zone (4), wherein the anoxic zone (4) is arranged between the anaerobic zone (3) and the aerobic zone.

3. The AAO+MBR sewage purification system according to claim 2, characterized in that: The aerobic zone is divided into a first aerobic zone (6) and a second aerobic zone (7), and the first aerobic zone (6) and the second aerobic zone (7) are arranged in sequence according to the flow direction of the sewage.

4. The AAO+MBR sewage purification system according to claim 3, characterized in that: The aeration pipe located at the end of the sewage flow in the second aerobic zone (7) is in a closed state.

5. The AAO+MBR sewage purification system according to claim 4, characterized in that: It also comprises a post-anoxic zone (8), wherein the post-anoxic zone (8) is arranged between the second aerobic zone (7) and the membrane pool (2).

6. The AAO+MBR sewage purification system according to claim 5, characterized in that: It also comprises a reaction pool (10), wherein the membrane grid (1) is arranged at the water inlet end of the reaction pool (10), and the membrane pool (2) is arranged at the water outlet end of the reaction pool (10), and the water inlet end and the water outlet end of the reaction pool (10) are arranged opposite to each other; There are two biological reaction zones, which are respectively arranged on both sides of the center line of the reaction pool (10).

7. The AAO+MBR sewage purification system according to claim 6, characterized in that: The membrane grid (1) is arranged at the middle position of the water inlet end of the reaction tank (10), and the two anaerobic zones (3) of the two biological reaction zones are respectively arranged on both sides of the membrane grid (1); The anoxic zones (4) of the two biological reaction zones are respectively arranged on both sides of the reaction tank (10), and one end of the biological reaction zone close to the anaerobic zone (3) is connected to the anaerobic zone (3); The side of the two anaerobic zones (3) close to each other is set as the first aerobic zone (6), the side of the two first aerobic zones (6) close to each other is set as the second aerobic zone (7), and the end of the second aerobic zone (7) close to the membrane tank (2) is set as the post-anoxic zone (8).

8. The AAO+MBR sewage purification system according to claim 7, characterized in that: One end of the first aerobic zone (6) close to the membrane grid (1) is connected to the second aerobic zone (7); An alternating zone (5) is provided at one end of the first aerobic zone (6) close to the membrane tank (2), and the alternating zone (5) is connected to the anoxic zone (4).

9. The AAO+MBR sewage purification system according to claim 8, characterized in that: The reflux ratio from the anoxic zone (4) to the anaerobic zone (3) is set to 200%; the reflux ratio from the aerobic zone to the anoxic zone (4) is 200%, and the reflux ratio of the membrane pool (2) is set to 400%.

10. The AAO+MBR sewage purification system according to claim 9, characterized in that: The carbon source addition position is arranged at one end of the anoxic zone (4) close to the anaerobic zone (3), and the iron salt addition position is arranged at a position of the first aerobic zone (6) close to the second aerobic zone (7).

Images