AAOA+MBR sewage treatment reaction tank

Abstract

The utility model relates to the field of sewage treatment discloses a kind of AAOA+MBR sewage treatment reaction tank, including water inlet distribution channel, the both sides of water inlet distribution channel are fixedly connected with connecting assembly, the outside of water inlet distribution channel is fixedly connected with anaerobic zone, the connecting assembly includes gate, the outside of gate is fixedly connected with open channel flowmeter, the outside of one gate is fixedly connected with anaerobic zone, one end of another gate is fixedly connected with front anoxic zone, the front anoxic zone is fixedly connected with reflux pump, the other end of the front anoxic zone is fixedly connected with oxygen zone, the bottom of oxygen zone is equipped with aeration device, the outside of oxygen zone is fixedly connected with oxygen backflow channel, the outside of oxygen backflow channel is fixedly connected with reflux pump.In the utility model, by the setting of anaerobic zone, front anoxic zone, oxygen zone, rear anoxic zone, MBR membrane pool, jointly formed the five-stage process of AAOAO, strengthen nitrification denitrification effect, further improve the denitrification effect of system.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment, and in particular to an AAOA+MBR wastewater treatment reactor. Background Technology

[0002] Wastewater treatment plants employ processes including grit removal and sedimentation systems, sedimentation tanks, biological treatment tanks, deep filtration tanks, deodorization systems, disinfection systems, and sludge treatment systems. Among these, the biological treatment tank utilizes microorganisms to degrade and transform organic pollutants to purify wastewater, while the deep filtration tank is crucial for further removing suspended solids. These two processes are now indispensable in domestic municipal wastewater treatment facilities, determining the overall effluent quality of the wastewater treatment plant. The combined process using a membrane bioreactor (MBR) as its core yields particularly excellent effluent quality with very low overall land use requirements. Therefore, many technologies are researched and developed specifically for this process, aiming to improve its layout, rationality, and the reliability of its treatment effects. For example, Chinese patent CN215667631U designs an underground wastewater treatment system based on the AAO+MBR process. By arranging underground wastewater treatment units and underground driveways side-by-side on both sides of a narrow plot of land, it optimizes the compact layout, fully utilizes vertical space, and reduces earthwork excavation and land division. The system adopts a shared-wall structure and a layered design (equipment layer on the first basement level and structural layer on the second basement level), combining AAO biological treatment with MBR membrane separation technology to achieve integrated high-efficiency wastewater treatment and sludge transportation. Chinese patent CN116675380A proposes an MBR membrane underground integrated wastewater treatment system. By setting up multiple sedimentation tanks in the primary sedimentation tank, a wastewater lift pump installed in the middle, and a baffle mechanism, it effectively prevents sediment from entering the anoxic tank, reducing MBR membrane fouling and lowering the cleaning frequency. It also employs a reversible baffle plate and a cross-flow operation process, combined with the alternating use of multiple sedimentation tanks, to achieve continuous and efficient wastewater treatment, ultimately producing high-quality reclaimed water that meets standards.

[0003] However, in practical applications, wastewater treatment plants often face fluctuations in influent quality and load, especially for urban domestic wastewater treatment plants where there are significant differences in influent load between day and night. Factors such as high concentrations of organic matter, high nitrogen and phosphorus wastewater, and fluctuating wastewater loads can increase the demand for carbon sources and microorganisms in the biological treatment tank. When the influent quality is poor or the wastewater load suddenly increases, the wastewater treatment effect of the biological treatment tank will deteriorate if there are insufficient carbon sources and microorganisms. None of the aforementioned patents comprehensively consider the tank layout for water quality fluctuations. Once fluctuations in total nitrogen and total phosphorus in the influent occur, the only way to cope is to passively increase the internal reflux ratio and temporarily add carbon sources, which is costly.

[0004] Therefore, to ensure the effective operation of the biochemical system and improve the sewage treatment effect and stability of the biochemical tank, there is a need for a biochemical tank with good sewage treatment effect and a relatively compact and economical layout, which can reasonably regulate the carbon source supply and microbial resources in the biochemical tank, improve the utilization rate of carbon source and microorganisms in the biochemical tank to reduce costs. Utility Model Content

[0005] To overcome the above deficiencies, this utility model provides an AAOA+MBR wastewater treatment reactor, which aims to improve the existing technology by setting up multiple water inlet channels, sludge return channels, and return flow metering systems, and by grouping the tank body to enhance the ability to regulate carbon sources and microorganisms in the biological tank, thereby improving the utilization rate of carbon sources and microorganisms.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] An AAOA+MBR wastewater treatment reactor includes an inlet water distribution channel, with connecting components fixedly connected to both sides of the inlet water distribution channel, and the inlet water distribution channel is externally fixedly connected to the anaerobic zone and the pre-anoxic zone.

[0008] The connecting assembly includes gates, each gate having an open channel flow meter fixedly connected to its exterior. One gate has an anaerobic zone fixedly connected to its exterior, and another gate has a pre-anoxic zone fixedly connected to one end. The other end of the pre-anoxic zone has an aerobic zone fixedly connected to its exterior. A return pump is connected to the partition between the pre-anoxic zone and the anaerobic zone. An aeration device is provided at the bottom of the aerobic zone. An aerobic return channel is fixedly connected to the inner end of the aerobic zone, and a return pump is fixedly connected to the exterior of the aerobic return channel.

[0009] As a further description of the above technical solution:

[0010] The aeration device includes a microporous aeration device, with an air inlet pipe fixedly connected to the bottom of the microporous aeration device, and a blower fixedly connected to the outside of the air inlet pipe.

[0011] As a further description of the above technical solution:

[0012] The reflux pump has three positions. The first reflux pump is fixed between the pre-anoxic zone and the anaerobic zone. The second reflux pump is fixed at the end of the aerobic zone. The third reflux pump is fixed outside the aerobic zone. The second and third reflux pumps are respectively connected to an aerobic reflux channel and a membrane mixed liquor reflux channel. The inner walls of the aerobic reflux channel and the membrane mixed liquor reflux channel are fixedly connected to open channel flow meters.

[0013] As a further description of the above technical solution:

[0014] It also includes a post-anoxic zone, the outside of which is fixedly connected to a weir plate, the other end of which is fixedly connected to a coagulation reaction zone, the inner wall of which is fixedly connected to a vertical agitator, the other end of which is fixedly connected to a membrane water distribution zone, and the other end of which is fixedly connected to a membrane treatment channel.

[0015] As a further description of the above technical solution:

[0016] The membrane treatment channel is equipped with an MBR membrane module inside, and an MBR permeate pump is connected to the outside of the MBR membrane module. The MBR permeate pump is located in the membrane equipment area.

[0017] As a further description of the above technical solution:

[0018] An offline cleaning area is fixedly connected to the outside of the membrane equipment area, and the top of the MBR membrane module is slidably connected to the top of the offline cleaning area;

[0019] As a further description of the above technical solution:

[0020] A membrane recirculation zone is fixedly connected to the outside of the membrane treatment channel, and the membrane recirculation zone is connected to the membrane mixed liquor recirculation channel through the outer bottom of the membrane treatment channel.

[0021] This utility model has the following beneficial effects:

[0022] 1. In this utility model, the five-stage process of AAOAO is formed by setting up an anaerobic zone, a pre-anoxic zone, an aerobic zone, a post-anoxic zone, and an MBR membrane tank, together with the aerobic zone of the MBR membrane tank, to enhance the nitrification and denitrification effects and further improve the nitrogen removal effect of the system.

[0023] 2. In this utility model, by using straight partitions, arc-shaped partitions, staggered second guide plates, and staggered inlets and outlets of anaerobic and anoxic zones, the residence time of sewage in each zone is increased, allowing the sewage to react more fully and improving the sewage treatment effect.

[0024] 3. In this utility model, by setting up a mixed liquor return channel, the mixed liquor from the aerobic zone is returned to the anoxic zone, providing carbon source compounds and microorganisms for the anoxic zone; by setting up a sludge return channel, the sludge from the sedimentation tank is returned to the pre-anoxic zone, providing sufficient microbial quantity and species for the pre-anoxic zone, thereby realizing the regulation of carbon source in the biological treatment tank and the multiple utilization of microorganisms and bacterial communities, improving the utilization rate of carbon source, microorganisms and bacterial communities in the biological treatment tank and the degradation and transformation of organic matter, thus improving the sewage treatment effect;

[0025] 4. In this utility model, by setting a flow meter between the two outlets of the inlet channel, and in conjunction with the external flow meter before entering this utility model, the proportion of raw water entering the anaerobic zone and the pre-anoxic zone can be accurately allocated, the carbon source can be rationally allocated, and the utilization efficiency of the raw water carbon source can be improved.

[0026] 5. In this utility model, by installing open channel flow meters in the aerobic return channel and membrane return channel, the return flow rate is accurately measured, and the mixed liquor return ratio and sludge return ratio can be flexibly controlled and adjusted. In this way, the carbon source supply and microorganisms can be adjusted according to actual needs, providing sufficient microbial survival and metabolic reserves for the pre-anoxic zone and anoxic zone, increasing the biological load carrying capacity and shock load resistance of the pre-anoxic zone and anoxic zone, and improving the wastewater treatment efficiency and stability. Attached Figure Description

[0027] Figure 1 This is a schematic plan view of an AAOA+MBR wastewater treatment reactor proposed in this utility model;

[0028] Figure 2 This is a schematic diagram of the connection components of an AAOA+MBR wastewater treatment reactor proposed in this utility model;

[0029] Figure 3 This is a schematic diagram of the process flow of an AAOA+MBR wastewater treatment reactor proposed in this utility model.

[0030] Legend:

[0031] 1. Inlet water distribution channel; 2. Connecting components; 21. Gate; 22. Flow weir plate; 23. Vertical mixer; 24. Return pump; 25. MBR membrane module; 26. MBR permeate pump; 27. Open channel flow meter; 28. Aeration device; 281. Microporous aeration head device; 282. Air inlet pipe; 283. Blower; 3. Pre-anoxic zone; 4. Aerobic zone; 5. Post-anoxic zone; 6. Coagulation reaction zone; 7. Membrane water distribution zone; 8. Membrane treatment channel; 9. Membrane return zone; 10. Membrane equipment zone; 11. Offline cleaning zone; 12. Aerobic return channel; 13. Membrane mixed liquor return channel; 14. Inlet; 15. Anaerobic zone. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0033] Reference Figures 1 to 3One embodiment of this utility model is a wastewater treatment biochemical tank based on the AAOA+MBR process. It is used to take pre-treated urban domestic sewage, which is first metered by a metering facility and then enters this utility model for secondary treatment. After being disinfected by a disinfection facility, it can be discharged.

[0034] The wastewater treatment biological treatment tank includes an inlet water distribution channel 1, an anaerobic zone 2, a pre-anoxic zone 3, an aerobic zone 4, a post-anoxic zone 5, a coagulation reaction zone 6, a membrane water distribution zone 7, a membrane treatment channel 8, a membrane return zone 9, a membrane equipment zone 10, and an offline cleaning zone 11.

[0035] In this invention, the inlet distribution channel 1, anaerobic zone 2, pre-anoxic zone 3, aerobic zone 4, post-anoxic zone 5, coagulation reaction zone 6, membrane distribution zone 7, membrane treatment channel 8, and membrane return zone 9 are sequentially connected. The wastewater treated in the previous process (referring to pre-treated urban domestic sewage) is evenly distributed externally and metered by a metering device before entering the inlet distribution channel 1 of the two sets of tanks in this system. The distribution channel 1 has two outlet gates 21, one leading to the anaerobic zone 2 and the other to the pre-anoxic zone 3. An open channel flow meter 27 is installed between the two gates. By adjusting the opening of the two gates 21 and in conjunction with the flow meter, the amount of water entering the two zones can be adjusted.

[0036] Wastewater first enters anaerobic zone 2, and after treatment in the anaerobic zone, it enters pre-anoxic zone 3. In pre-anoxic zone 3, the wastewater undergoes denitrification to remove ammonia nitrogen. At the same time, a return pump 24 is installed at the end of pre-anoxic zone 3 to return the remaining carbon source in pre-anoxic zone 3 to anaerobic zone 2.

[0037] The wastewater then flows through aerobic zone 4, where an aeration device 28 is installed at the bottom. This device includes several microporous aeration heads 281, an air inlet pipe 282, and a blower 283. Oxygen is supplied through the aeration device 28 to mix and agitate the wastewater, which is then discharged into the post-anoxic zone 5. Simultaneously, an aerobic zone return pump 24 is also installed at the end of aerobic zone 4 to lift the wastewater and return it through the aerobic return channel 12 and an open channel flow meter 27 to the pre-anoxic zone 3.

[0038] The post-anoxic zone 5 has the same function as the pre-anoxic zone 3. Through the action of denitrifying bacteria, nitrate nitrogen (NO3N) in the wastewater undergoes a biochemical reaction and is converted into nitrogen gas (N2) for discharge, thereby achieving the goal of denitrification of wastewater.

[0039] The effluent from the post-anoxic zone 5 overflows through the weir plate 22 into the coagulation reaction zone 6. The coagulation reaction zone 6 is equipped with a dosing point and a vertical agitator 23. By adding coagulating agents, the colloids in the water are agglomerated, which is beneficial for the retention of colloids in the subsequent MBR stage.

[0040] Wastewater entering the MBR area sequentially passes through the membrane distribution zone 7, the membrane treatment channel 8, and the membrane return zone 9. The membrane distribution zone 7 acts as an intermediate water distribution point, ensuring a balanced flow and quality of water entering the membrane treatment channel 8. This invention sets the membrane return zone 9 and the membrane mixed liquor return channel 13 at the same height, while simultaneously raising the heights of the membrane distribution zone 7 and the membrane treatment channel 8. This allows for a connecting channel between the membrane return zone 9 and the membrane mixed liquor return channel 13 at their bottoms. Therefore, wastewater from the membrane treatment zone 8, in addition to being pumped out by the MBR permeate pump 26 located in the membrane equipment zone 10, continuously flows towards the membrane return zone 9 and the membrane mixed liquor return channel 13 under the suction of the return pump 24 in the membrane mixed liquor return channel 13, and is then pressurized into the aerobic zone 4 by the return pump 24. The membrane mixed liquor recirculation ratio is 400%.

[0041] The permeate pump, sludge pump, and other equipment in the MBR membrane treatment equipment are all located in the MBR membrane equipment area 10. When the membrane fouling on the MBR membrane module 25 is large or the transmembrane pressure difference is large, the MBR membrane module can be moved to the offline cleaning area 11 for chemical soaking and cleaning.

[0042] Working principle: In anaerobic zone 2, due to the lack of oxygen supply, the dissolved oxygen in the water drops below 0.2 mg / L, and there is no nitrate nitrogen (NO3⁻N), thus forming an anaerobic environment. Under anaerobic conditions, non-edema polyphosphate-accumulating bacteria cannot utilize oxygen or nitrate nitrogen as electron acceptors, and instead decompose the polyphosphates stored in their bodies, releasing phosphates into the water for further processing in the subsequent aerobic environment.

[0043] In the pre-anoxic zone 3 and post-anoxic zone 5, due to the lack of oxygen supply, anoxic conditions are formed in the water (DO < 0.5 mg / L, nitrate nitrogen NO3⁻N is present but no free oxygen). Denitrifying bacteria use the carbon source provided by the sewage directly entering from the anaerobic zone 2 and the inlet distribution channel 1 to reduce the returned nitrate nitrogen to nitrogen gas, thereby achieving denitrification. At the same time, it alleviates carbon source competition to assist the subsequent biological phosphorus removal in the anaerobic zone. The pre-anoxic zone 3 is equipped with a return equipment to return the terminal sewage to the anaerobic zone 3, which can improve the phosphorus release efficiency of polyphosphate-accumulating bacteria, while reducing the damage to the anaerobic environment caused by the direct return of nitrate nitrogen from the aerobic zone 4, thus optimizing the denitrification and phosphorus removal effect.

[0044] In aerobic zone 4, wastewater undergoes aerobic biochemical treatment and transformation in this zone, further degrading the organic matter in the wastewater and converting ammonia nitrogen in the wastewater into nitrate nitrogen.

[0045] In the membrane treatment channel 8, a series of MBR membrane modules 25 are immersed. Utilizing the principle of negative pressure suction, a transmembrane pressure difference is generated on the surface of the MBR membrane. Through the physical interception effect of the fine pores on the membrane fibers, suspended pollutants in the water are intercepted on the surface of the MBR membrane fibers under the suction of the MBR permeate pump 26, thereby achieving purification and separation. Simultaneously, under the continuous cleaning of the aeration system, the MBR membrane modules 25 also achieve the removal and detachment of surface-intercepted pollutants, maintaining a high sludge concentration (1.0~1.5 g / L) in the membrane treatment channel 8.

[0046] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An AAOA+MBR wastewater treatment reactor, comprising an inlet water distribution channel (1), characterized in that: Both sides of the water inlet distribution channel (1) are fixedly connected to the connecting components (2), and the outside of the water inlet distribution channel (1) is fixedly connected to the anaerobic zone (15) and the pre-anoxic zone (3). The connecting assembly (2) includes a gate (21), and an open channel flow meter (27) is fixedly connected to the outside of each gate (21). An anaerobic zone (15) is fixedly connected to the outside of one gate (21), and a pre-anoxic zone (3) is fixedly connected to one end of the other gate (21). An aerobic zone (4) is fixedly connected to the other end of the pre-anoxic zone (3). A return pump (24) is connected to the partition between the pre-anoxic zone (3) and the anaerobic zone (15). An aeration device (28) is provided at the bottom of the aerobic zone (4). An aerobic return channel (12) is fixedly connected to the inner end of the aerobic zone (4). A return pump (24) is fixedly connected to the outside of the aerobic return channel (12).

2. The AAOA+MBR wastewater treatment reactor according to claim 1, characterized in that: The aeration device (28) includes a microporous aeration device (281), with an air inlet pipe (282) fixedly connected to the bottom of the microporous aeration device (281), and a blower (283) fixedly connected to the outside of the air inlet pipe (282).

3. The AAOA+MBR wastewater treatment reactor according to claim 1, characterized in that: The reflux pump (24) has three positions. Position 1 of the reflux pump (24) is fixed between the pre-anoxic zone (3) and the anaerobic zone (15). Position 2 of the reflux pump (24) is fixed at the end inside the aerobic zone (4). Position 3 of the reflux pump (24) is fixed outside the aerobic zone (4). Positions 2 and 3 of the reflux pump (24) are respectively connected to an aerobic reflux channel (12) and a membrane mixed liquor reflux channel (13). The inner walls of the aerobic reflux channel (12) and the membrane mixed liquor reflux channel (13) are fixedly connected to open channel flow meters (27).

4. The AAOA+MBR wastewater treatment reactor according to claim 1, characterized in that: It also includes a post-anoxic zone (5), to which an overflow weir plate (22) is fixedly connected. At the other end of the overflow weir plate (22), a coagulation reaction zone (6) is fixedly connected. A vertical agitator (23) is fixedly connected to the inner wall of the coagulation reaction zone (6). At the other end of the coagulation reaction zone (6), a membrane water distribution zone (7) is fixedly connected. At the other end of the membrane water distribution zone (7), a membrane treatment channel (8) is fixedly connected.

5. The AAOA+MBR wastewater treatment reactor according to claim 4, characterized in that: The membrane treatment channel (8) is equipped with an MBR membrane module (25) inside, and an MBR permeate pump (26) is connected to the outside of the MBR membrane module (25). The MBR permeate pump (26) is located in the membrane equipment area (10).

6. The AAOA+MBR wastewater treatment reactor according to claim 5, characterized in that: An offline cleaning zone (11) is fixedly connected to the outside of the membrane equipment area (10), and the top of the MBR membrane module (25) is slidably connected to the top of the offline cleaning zone (11).

7. The AAOA+MBR wastewater treatment reactor according to claim 6, characterized in that: The membrane treatment channel (8) is fixedly connected to the outside of the membrane reflux zone (9), and the membrane reflux zone (9) is connected to the membrane mixed liquor reflux channel (13) through the bottom of the membrane treatment channel (8).

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