Device and method for realizing short-cut nitrification and short-cut denitrification coupled anaerobic ammonia oxidation low-carbon-nitrogen-ratio sewage denitrification based on two-stage membrane aeration bio-membrane reactor
By using a two-stage membrane aeration biofilm reactor to couple short-cut nitrification and short-cut denitrification with anaerobic ammonia oxidation, the problems of high energy consumption, large carbon source consumption and system instability in the treatment of wastewater with low carbon-to-nitrogen ratios have been solved, achieving efficient deep denitrification and stable operation.
Patent Information
- Application Number
- CN202510598882.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-09
- Publication Date
- 2025-11-18
AI Technical Summary
Existing technologies for treating urban wastewater with low carbon-to-nitrogen ratios suffer from high energy consumption, large carbon source depletion, high greenhouse gas emissions, and poor system stability, making it difficult to achieve efficient and deep denitrification.
A short-cut nitrification and short-cut denitrification coupled anaerobic ammonia oxidation process based on a two-stage membrane aerated biofilm reactor (MABR) is adopted. Simultaneous nitrification and denitrification are achieved through the MABR system, optimizing the stratified structure of the microbial community, precisely controlling the addition of oxygen and carbon sources, and combining PD/A technology to reduce the need for external carbon sources and aeration.
It significantly improves the denitrification efficiency of wastewater with low carbon-to-nitrogen ratio, reduces energy consumption and carbon source consumption, reduces greenhouse gas emissions, enhances system stability and tolerance to shock loads, and optimizes the treatment capacity of complex wastewater.
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Figure CN120964988A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a process technology for realizing short-cut nitrification and short-cut denitrification coupled anaerobic ammonia oxidation low carbon-nitrogen ratio wastewater denitrification based on a two-stage membrane aerated biofilm reactor, and belongs to the field of biological wastewater treatment. BACKGROUND
[0002] With the acceleration of urbanization, municipal wastewater treatment is facing the dual challenges of meeting discharge standards and energy saving and consumption reduction. In recent years, although organic pollution has been controlled to some extent, the excessive discharge of nutrients such as nitrogen and phosphorus has led to increasingly serious water eutrophication problems, and denitrification and phosphorus removal have become a major demand for water pollution control. However, municipal wastewater in China generally presents a low carbon-nitrogen ratio, and traditional denitrification processes require a large amount of aeration energy consumption and external organic carbon sources, while being accompanied by a large amount of excess sludge treatment and greenhouse gas emissions and other secondary pollution problems. Therefore, developing low-carbon and efficient advanced denitrification technology has become an urgent need in the field of wastewater treatment.
[0003] PD / A technology is one of the current efficient biological denitrification technologies. Under anoxic conditions, the technology reduces nitrate to nitrite through short-cut denitrification, and then uses anaerobic ammonia oxidation bacteria to convert nitrite and ammonia nitrogen into nitrogen, thereby achieving deep denitrification. This process theoretically does not require external carbon source and aeration, significantly reducing carbon source consumption and greenhouse gas emissions, and has outstanding energy-saving and environmental advantages. At the same time, short-cut denitrification can reduce waste sludge production and improve denitrification efficiency. In addition, the process also has the characteristics of flexible operation and strong adaptability, and is suitable for treating low carbon-nitrogen ratio wastewater. However, in actual operation, the process may still need to add external organic carbon source to support the denitrification process, and the supply of nitrite is unstable and is easily affected by competition from heterotrophic denitrifying bacteria. In addition, precise control of parameters such as dissolved oxygen, carbon source dosage, and pH is also a challenge faced by the process.
[0004] MABR is a new type of wastewater treatment system that combines gas separation membrane technology and biofilm treatment technology, and has the advantages of membrane aeration and immobilized biofilm, with significant energy-saving and high-efficiency denitrification potential. MABR uses bubble-free aeration, with an oxygen utilization rate close to 100%, and the formation of an aerobic-anoxic microbial community stratification structure inside the biofilm can achieve simultaneous nitrification and denitrification, significantly improving denitrification efficiency. Through efficient oxygen transfer and biofilm partitioning, the technology can precisely control parameters such as dissolved oxygen and carbon source dosage, optimize the distribution of microorganisms within the biofilm, and improve the adaptability and stability of the system. In addition, MABR technology also has the advantages of small footprint, low operating cost, easy coupling with other processes, etc.
[0005] In view of the demand for advanced denitrification and resource utilization in urban sewage treatment, and in combination with the shortcomings of the prior art, the present application provides an advanced denitrification process based on PD / A. The process realizes efficient oxygen transfer and microbial community stratification through MABR technology, providing a new process route and solution for urban sewage and sludge treatment. SUMMARY
[0006] The present application is based on short-cut nitrification and short-cut denitrification coupled with anaerobic ammonia oxidation technology, membrane aeration biofilm reactor technology and wastewater treatment process control technology, and provides an advanced denitrification process for realizing simultaneous nitrification and denitrification enhanced anaerobic ammonia oxidation using a MABR system, to achieve efficient denitrification of low carbon-nitrogen ratio urban sewage.
[0007] The object of the present application is achieved by the following technical solutions:
[0008] A device for realizing short-cut nitrification and short-cut denitrification coupled with anaerobic ammonia oxidation for denitrification of low carbon-nitrogen ratio sewage based on a two-stage membrane aeration biofilm reactor, characterized in that it comprises a municipal sewage tank (1), an anoxic section MABR tank (2), a first intermediate tank (3), an aerobic section MABR tank (4), and a second intermediate tank (5). The anoxic section MABR tank (2) is provided with a first peristaltic pump (2.1), a blower (2.2), a first pressure sensor (2.3), a first gas supply pipe (2.4), a first aeration valve (2.5), a first stirring device (2.6), a first pH probe (2.7), a first DO probe (2.8), a first multi-parameter measuring instrument (2.9), a first MABR membrane assembly (2.10), a first gas supply pipe (2.11), a first water inlet pipe (2.12), a first water inlet (2.13), a first water outlet (2.14), and a first water outlet pipe (2.15). The aerobic section MABR tank (4) is provided with a second peristaltic pump (4.1), a second pressure sensor (4.2), a second aeration valve (4.3), a second gas supply pipe (4.4), a second stirring device (4.5), a second pH probe (4.6), a second DO probe (4.7), a second multi-parameter measuring instrument (4.8), a second MABR membrane assembly (4.9), a second water inlet pipe (4.10), a second water inlet (4.11), a second water outlet (4.12), and a second water outlet pipe (4.13). The second intermediate tank (5) is provided with a third peristaltic pump (5.1) and a backflow pipe (5.2). The municipal sewage tank is connected to the first water inlet of the anoxic section MABR tank by the first water inlet pipe through the first peristaltic pump, and the water outlet of the anoxic section MABR tank is connected to the first intermediate tank. The first intermediate tank is connected to the water inlet of the aerobic section MABR tank by the second water inlet pipe through the second peristaltic pump, and the water outlet of the aerobic section MABR tank is connected to the second intermediate tank. Part of the effluent is backflowed to the anoxic section MABR tank through the backflow pipe by the third peristaltic pump to provide nitrate nitrogen for the anoxic section MABR tank.
[0009] A method for realizing short-cut nitrification and short-cut denitrification coupled anaerobic ammonia oxidation low carbon-nitrogen ratio wastewater denitrification based on two-stage membrane aeration biofilm reactor, characterized in that it comprises the following steps:
[0010] (1) Anoxic MABR tank start-up stage
[0011] In the start-up stage, residual sludge and anaerobic ammonia oxidation sludge from a wastewater treatment plant are inoculated into the anoxic MABR tank, and the sludge concentration is controlled at 2.0-6.0 gVSS / L; the first peristaltic pump is turned on, and municipal wastewater is pumped into the anoxic MABR tank through the first water inlet pipe; after the water is fed, the first peristaltic pump is turned off; the air blower is turned on, so that the gas supply pressure of the MABR membrane assembly is controlled in the range of 15-20 KPa, and the dissolved oxygen concentration in the biofilm zone is controlled at 0.2-0.5 mg / L; at the same time, the stirring device is turned on; after 2.0-3.0 h of reaction, the aeration device and the stirring device are turned off; the sedimentation stage is entered, and the sedimentation is performed for 0.5-1.5 h; after the sedimentation is completed, the supernatant is discharged to the intermediate water tank, and the drainage ratio is 50%-70%; when the nitrate nitrogen removal rate of the anoxic MABR tank is higher than 80%, and the continuous stable operation is more than 7 days, the sludge concentration on the MABR biofilm is greater than or equal to 1.0 gVSS / L, and the anoxic MABR tank is successfully started up.
[0012] (2) Aerobic MABR tank start-up stage
[0013] First, residual sludge and anaerobic ammonia oxidation sludge are inoculated into the aerobic MABR tank, and the sludge concentration is controlled at 2.0-5.0 gVSS / L; the aerobic MABR tank adopts intermittent operation mode, and the operation stage is divided into water feeding, aeration, sedimentation, drainage and idling; the effluent of the first intermediate water tank enters the aerobic MABR tank through the second water inlet pipe; after the water feeding is completed, the aeration device is turned on, so that the gas supply pressure of the MABR membrane assembly is controlled in the range of 20-25 KPa, and the dissolved oxygen concentration in the biofilm zone is controlled at 0.5-1.5 mg / L; at the same time, the stirring device is turned on; the reaction time is controlled at 4.0-8.0 h; after the aeration is completed, the aeration device is turned off, the sedimentation is performed for 0.5-1.0 h, and the drainage ratio is 40%-60%; the effluent is backflowed to the anoxic MABR tank, and the ratio of the backflow amount to the municipal wastewater feeding amount is 1.5-3.0; when the ammonia nitrogen removal rate of the aerobic MABR tank is higher than 80%, and the continuous stable operation is more than 7 days, the sludge concentration on the MABR biofilm is greater than or equal to 0.8 gVSS / L, and the aerobic MABR tank is successfully started up.
[0014] (3) Two-stage MABR system series operation load increasing stage
[0015] After the start-up of the anoxic MABR tank and the aerobic MABR tank, the system enters a load increasing stage; in this stage, the municipal wastewater successively passes through the anoxic MABR tank and the aerobic MABR tank, and both tanks adopt an intermittent operation mode; in the anoxic MABR tank, the MABR membrane aeration in the aeration stage adopts a pulse aeration mode, aeration for 40 min, stop for 20 min, the gas supply pressure is controlled at 17-22 KPa, and the reaction time is controlled at 1.5-2.5 h; when the nitrate nitrogen removal rate is higher than 80% and continuously and stably operated for more than 7 days, the aeration is adjusted to 30 min, the stop is 30 min, the gas supply pressure is controlled at 19-24 KPa, and the reaction time is 1.0-2.0 h, at this time, the nitrate nitrogen removal rate of the anoxic MABR tank is higher than 80% and continuously and stably operated for more than 7 days, and the system is long-term and stably operated under this condition; in the aerobic MABR tank, the MABR membrane aeration in the aeration stage adopts a pulse aeration mode, aeration for 40 min, stop for 20 min, the gas supply pressure is controlled at 22-27 KPa, and the reaction time is controlled at 3.0-7.0 h; when the ammonia nitrogen removal rate is higher than 80% and continuously and stably operated for more than 7 days, the aeration is adjusted to 30 min, the stop is 30 min, the gas supply pressure is controlled at 24-29 KPa, and the reaction time is 2.0-6.0 h, at this time, the ammonia nitrogen removal rate of the aerobic MABR tank is higher than 80% and continuously and stably operated for more than 7 days, and the system is long-term and stably operated under this condition.
[0016] The two-stage membrane aeration biological membrane reactor device for realizing short-cut nitrification and short-cut denitrification coupled anaerobic ammonia oxidation of low carbon-nitrogen ratio wastewater denitrification provided by the application has the following advantages:
[0017] (1) The MABR system realizes bubbleless aeration by using gas permeable membrane material, the theoretical oxygen transfer efficiency can reach 100%, and the oxygen concentration can be accurately controlled. This feature creates a unique oxygen concentration gradient for the microorganisms in the biofilm, enabling nitrosobacteria, nitrifying bacteria and anaerobic ammonia oxidation bacteria to coexist and synergize in the same system, thereby realizing simultaneous nitrification and denitrification. By optimizing the nitrogen conversion path, the MABR system significantly improves the denitrification efficiency, especially when treating low carbon-nitrogen ratio wastewater, it can still maintain a high total nitrogen removal rate.
[0018] (2) Anaerobic ammonia oxidation bacteria grow slowly and are extremely sensitive to environmental changes, with strict growth conditions, which makes the stability of the traditional system poor during operation and difficult to resist external impact load. In contrast, the MABR system provides a stable attachment site for microorganisms through the membrane material, promoting the formation of a biofilm. Inside the biofilm, the microbial community presents a layered structure, and different types of microorganisms can grow and reproduce in their respective suitable microenvironments. This layered structure not only provides stable living conditions for anaerobic ammonia oxidation bacteria, but also enhances the stability of the entire system, significantly improving the system's tolerance to impact loads.
[0019] (3) In traditional wastewater treatment processes, the low carbon-nitrogen ratio wastewater is limited by the lack of carbon source, which restricts the denitrification process, resulting in a significant decrease in nitrogen removal efficiency. However, the MABR system can achieve efficient simultaneous nitrification and denitrification under low carbon-nitrogen ratio conditions by optimizing the microbial community structure in the biofilm. At the same time, the MABR system provides a stable growth environment for anaerobic ammonia oxidation bacteria, further improving the total nitrogen removal rate, thereby strengthening the contribution of anaerobic ammonia oxidation to the treatment of low carbon-nitrogen ratio wastewater. In addition, the combination of MABR and PD / A process not only can effectively treat wastewater with low carbon-nitrogen ratio and high ammonia nitrogen concentration, but also can degrade refractory organic pollutants, thereby significantly improving the treatment capacity of complex wastewater.
[0020] (4) Nitrous oxide, as an intermediate product of nitrification and denitrification, has a greenhouse effect 265 times stronger than carbon dioxide. In traditional processes, dissolved oxygen fluctuation, carbon source deficiency, and microbial community imbalance can easily lead to the accumulation of nitrous oxide; in the nitrification stage, low dissolved oxygen inhibits the hydroxylamine oxidase activity of ammonia-oxidizing bacteria, promoting the generation of nitrous oxide through chemical decomposition or enzymatic bypass; in the denitrification stage, carbon source deficiency or dissolved oxygen intrusion will interrupt the electron transport chain, causing denitrification to stop at nitrous oxide. The MABR system precisely regulates the oxygen concentration gradient in the biofilm through the bubbleless aeration technology of gas permeable membrane, providing stable and sufficient dissolved oxygen in the oxygen-rich zone; in the anoxic zone, the coupling of NH4 + and NO2 - is directly achieved through simultaneous nitrification and denitrification and anaerobic ammonia oxidation pathways, significantly shortening the nitrogen conversion path and avoiding the multi-step reduction reaction of NO2 - → NO → N2O → N2 in the denitrification process, thereby significantly reducing the generation and escape of nitrous oxide. BRIEF DESCRIPTION OF DRAWINGS
[0021] Figure 1 is a schematic diagram of the device of the present application.
[0022] 1 - City sewage tank, 2 - Anoxic MABR tank, 2.1 - First peristaltic pump, 2.2 - Air blower, 2.3 - First pressure sensor, 2.4 - First air supply pipe, 2.5 - First aeration valve, 2.6 - First stirring device, 2.7 - First pH probe, 2.8 - First DO probe, 2.9 - First multi-parameter meter, 2.10 - First MABR membrane module, 2.11 - First air supply pipe, 2.12 - First water inlet pipe, 2.13 - First water inlet, 2.14 - First water outlet, 2.15 - First water outlet pipe, 3 - First intermediate water tank, 4 - Aerobic MABR tank, 4.1 - Second peristaltic pump, 4.2 - Second pressure sensor, 4.3 - Second aeration valve, 4.4 - Second air supply pipe, 4.5 - Second stirring device, 4.6 - Second pH probe, 4.7 - Second DO probe, 4.8 - Second multi-parameter meter, 4.9 - Second MABR membrane module, 4.10 - Second water inlet pipe, 4.11 - Second water inlet, 4.12 - Second water outlet, 4.13 - Second water outlet pipe, 4.14 - Second water outlet pipe, 5.1 - Third peristaltic pump, 5.2 - Backflow pipe. DETAILED DESCRIPTION
[0023] The application is further illustrated in combination with the drawings and examples. As shown in the drawings, a device for realizing short-cut nitrification and short-cut denitrification coupled with anaerobic ammonia oxidation for denitrification of low-carbon-nitrogen-ratio sewage based on a two-stage membrane aerated biofilm reactor, characterized in that it comprises a municipal sewage tank (1), an anoxic MABR tank (2), a first intermediate tank (3), an aerobic MABR tank (4), and a second intermediate tank (5). The anoxic MABR tank (2) is provided with a first peristaltic pump (2.1), a blower (2.2), a first pressure sensor (2.3), a first gas supply pipe (2.4), a first aeration valve (2.5), a first stirring device (2.6), a first pH probe (2.7), a first DO probe (2.8), a first multi-parameter measuring instrument (2.9), a first MABR membrane assembly (2.10), a first gas supply pipe (2.11), a first water inlet pipe (2.12), a first water inlet (2.13), a first water outlet (2.14), and a first water outlet pipe (2.15). The aerobic MABR tank (4) is provided with a second peristaltic pump (4.1), a second pressure sensor (4.2), a second aeration valve (4.3), a second gas supply pipe (4.4), a second stirring device (4.5), a second pH probe (4.6), a second DO probe (4.7), a second multi-parameter measuring instrument (4.8), a second MABR membrane assembly (4.9), a second water inlet pipe (4.10), a second water inlet (4.11), a second water outlet (4.12), and a second water outlet pipe (4.13). The second intermediate tank (5) is provided with a third peristaltic pump (5.1) and a reflux pipe (5.2). The municipal sewage tank is connected to the first water inlet of the anoxic MABR tank by the first water inlet pipe through the first peristaltic pump, and the water outlet of the anoxic MABR tank is connected to the first intermediate tank. The first intermediate tank is connected to the water inlet of the aerobic MABR tank by the second water inlet pipe through the second peristaltic pump, and the water outlet of the aerobic MABR tank is connected to the second intermediate tank. Part of the effluent is refluxed to the anoxic MABR tank by the reflux pipe through the third peristaltic pump to provide nitrate nitrogen for the anoxic MABR tank.
[0024] A method for realizing short-cut nitrification and short-cut denitrification coupled with anaerobic ammonia oxidation for denitrification of low-carbon-nitrogen-ratio sewage by a two-stage membrane aerated biofilm reactor, comprising the following steps:
[0025] (1) Anoxic MABR tank start-up stage
[0026] In the start-up phase, the residual sludge and anammox sludge from a sewage treatment plant are inoculated into the anoxic MABR tank, and the sludge concentration is controlled at 4.0 gVSS / L after inoculation; the first peristaltic pump is turned on, and the municipal wastewater is pumped into the anoxic MABR tank through the first water inlet pipe; after the water is fed, the first peristaltic pump is turned off; the air blower is turned on, so that the gas supply pressure of the MABR membrane assembly is controlled in the range of 15-20 KPa, and the dissolved oxygen concentration in the biological membrane zone is controlled at 0.2-0.5 mg / L, and at the same time, the stirring device is turned on; after 2.5 h of reaction, the aeration device and the stirring device are turned off; the sedimentation phase is entered, and the sedimentation is performed for 1.0 h; after the sedimentation is completed, the supernatant is discharged to the intermediate water tank, and the drainage ratio is 60%; when the removal rate of nitrate nitrogen in the anoxic MABR tank is higher than 80%, and the continuous and stable operation is more than 7 days, the sludge concentration on the MABR biofilm is greater than or equal to 1.0 gVSS / L, and the anoxic MABR tank is successfully started.
[0027] (2) Start-up phase of the aerobic MABR tank
[0028] First, the residual sludge and anammox sludge are inoculated into the aerobic MABR tank, and the sludge concentration is controlled at 3.5 gVSS / L after inoculation; the aerobic MABR tank adopts an intermittent operation mode, and the operation phase is divided into water feeding, aeration, sedimentation, drainage and idling; the effluent of the first intermediate water tank enters the aerobic MABR tank through the second water inlet pipe; after the water feeding is completed, the aeration device is turned on, so that the gas supply pressure of the MABR membrane assembly is controlled in the range of 20-25 KPa, and the dissolved oxygen concentration in the biological membrane zone is controlled at 0.5-1.5 mg / L, and at the same time, the stirring device is turned on; the reaction time is 6.0 h; after the aeration is completed, the aeration device is turned off, the sedimentation is performed for 0.7 h, and the drainage ratio is 50%; the effluent is returned to the anoxic MABR tank, and the ratio of the return water amount to the municipal wastewater inlet amount is 2.3; when the removal rate of ammonia nitrogen in the aerobic MABR tank is higher than 80%, and the continuous and stable operation is more than 7 days, the sludge concentration on the MABR biofilm is greater than or equal to 0.8 gVSS / L, and the aerobic MABR tank is successfully started.
[0029] (3) Load increasing phase of the two-stage MABR system in series
[0030] After the start-up of the anoxic MABR tank and the aerobic MABR tank, the system enters the load increasing stage. In this stage, the municipal wastewater is sequentially treated by the anoxic MABR tank and the aerobic MABR tank, and both tanks are operated in an intermittent mode. In the anoxic MABR tank, the MABR membrane aeration is operated in a pulse mode during the aeration stage, with aeration for 40 min and stopping for 20 min. The air supply pressure is controlled at 17-22 KPa, and the reaction time is controlled at 2.0 h. When the nitrate removal rate is higher than 80% and the system is continuously and stably operated for more than 7 days, the aeration time is adjusted to 30 min and the stopping time is adjusted to 30 min. The air supply pressure is controlled at 19-24 KPa, and the reaction time is 1.5 h. When the nitrate removal rate of the anoxic MABR tank is higher than 80% and the system is continuously and stably operated for more than 7 days, the system is operated under the above conditions for long-term stable operation. In the aerobic MABR tank, the MABR membrane aeration is operated in a pulse mode during the aeration stage, with aeration for 40 min and stopping for 20 min. The air supply pressure is controlled at 22-27 KPa, and the reaction time is controlled at 5.0 h. When the ammonia nitrogen removal rate is higher than 80% and the system is continuously and stably operated for more than 7 days, the aeration time is adjusted to 30 min and the stopping time is adjusted to 30 min. The air supply pressure is controlled at 24-29 KPa, and the reaction time is 4.0 h. When the ammonia nitrogen removal rate of the aerobic MABR tank is higher than 80% and the system is continuously and stably operated for more than 7 days, the system is operated under the above conditions for long-term stable operation.
[0031] The specific test water is the wastewater from a public bathroom of a school, with an average ammonia nitrogen concentration of 61.3 mg / L and an average COD concentration of 119.8 mg / L. After long-term operation for 120 days, the average nitrate removal rate of the anoxic MABR tank is 86%, and the average ammonia nitrogen effluent concentration of the aerobic MABR tank is 5.2 mg / L. The average nitrate removal rate of the aerobic MABR tank is 87%, and the municipal wastewater is stably and deeply denitrified.
Claims
1. A device for denitrification of low carbon-nitrogen ratio wastewater based on two-stage membrane aerated biofilm reactor for short-cut nitrification and short-cut denitrification coupled with anaerobic ammonia oxidation, characterized in that, The application relates to a sewage treatment system, which comprises a municipal sewage tank (1), an anoxic MABR tank (2), a first intermediate tank (3), an aerobic MABR tank (4) and a second intermediate tank (5). The anoxic MABR tank (2) is provided with a first peristaltic pump (2.1), a blower (2.2), a first pressure sensor (2.3), a first air supply pipe (2.4), a first aeration valve (2.5), a first stirring device (2.6), a first pH probe (2.7), a first DO probe (2.8), a first multi-parameter measuring instrument (2.9), a first MABR membrane assembly (2.10), a first air supply pipe (2.11), a first water inlet pipe (2.12), a first water inlet (2.13), a first water outlet (2.14) and a first water outlet pipe (2.15). The aerobic MABR tank (4) is provided with a second peristaltic pump (4.1), a second pressure sensor (4.2), a second aeration valve (4.3), a second air supply pipe (4.4), a second stirring device (4.5), a second pH probe (4.6), a second DO probe (4.7), a second multi-parameter measuring instrument (4.8), a second MABR membrane assembly (4.9), a second water inlet pipe (4.10), a second water inlet (4.11), a second water outlet (4.12) and a second water outlet pipe (4.13). The second intermediate tank (5) is provided with a third peristaltic pump (5.1) and a backflow pipe (5.2). The municipal sewage tank is connected with the first water inlet of the anoxic MABR tank through the first water inlet pipe by the first peristaltic pump. The water outlet of the anoxic MABR tank is connected with the first intermediate tank. The first intermediate tank is connected with the water inlet of the aerobic MABR tank through the second water inlet pipe by the second peristaltic pump. The water outlet of the aerobic MABR tank is connected with the second intermediate tank. Part of the effluent is backflowed to the anoxic MABR tank through the backflow pipe by the third peristaltic pump.
2. A method of using the apparatus of claim 1, characterized in that, The application also discloses a sewage treatment method. (1) Anoxic MABR tank starting stage In the starting stage, residual sludge and anaerobic ammonia oxidation sludge in a sewage treatment plant are inoculated into the anoxic MABR tank, and the sludge concentration is controlled to be 2.0-6.0 gVSS / L. The first peristaltic pump is started, and the municipal sewage is pumped into the anoxic MABR tank through the first water inlet pipe. After the water is fed, the first peristaltic pump is closed. The blower is started, the air supply pressure range of the MABR membrane assembly is controlled to be 15-20 KPa, the dissolved oxygen concentration in the biological membrane zone is controlled to be 0.2-0.5 mg / L, the stirring device is started, and after 2.0-3.0 hours, the aeration device and the stirring device are closed. The sedimentation stage is entered, the sedimentation is carried out for 0.5-1.5 hours, the supernatant is discharged to the intermediate tank after the sedimentation is completed, and the drainage ratio is 50%-70%. When the nitrate nitrogen removal rate of the anoxic MABR tank is higher than 80% and the continuous stable operation is more than 7 days, the sludge concentration on the MABR biological membrane is greater than or equal to 1.0 gVSS / L, and the anoxic MABR tank is successfully started; (2) Aerobic MABR tank starting stage First, the aerobic section MABR tank is inoculated with residual sludge and anaerobic ammonia oxidation sludge, and the sludge concentration is controlled at 2.0-5.0 gVSS / L after inoculation; the aerobic section MABR tank is operated in an intermittent mode, and the operation stage is divided into water feeding, aeration, sedimentation, water drainage and idling; the effluent of the first intermediate water tank enters the aerobic section MABR tank through the second water feeding pipe; after water feeding is completed, the aeration device is started, the gas supply pressure of the MABR membrane module is controlled in the range of 20-25 KPa, the dissolved oxygen concentration in the biological membrane zone is controlled in the range of 0.5-1.5 mg / L, and the stirring device is started at the same time; the reaction time is controlled in the range of 4.0-8.0 h; after aeration is completed, the aeration device is turned off, the sedimentation time is 0.5-1.0 h, and the water drainage ratio is 40%-60%; the effluent is returned to the anoxic section MABR tank, and the ratio of the return water amount to the municipal sewage water feeding amount is 1.5-3.0; when the ammonia nitrogen removal rate of the aerobic section MABR tank is higher than 80% and the continuous stable operation is more than 7 days, the sludge concentration on the MABR biological membrane is greater than or equal to 0.8 gVSS / L, and the aerobic section MABR tank is successfully started; (3) Load increasing stage of two-stage MABR system in series The municipal sewage passes through the anoxic section and the aerobic section MABR tanks in sequence, and both tanks are operated in an intermittent mode; in the anoxic section MABR tank, the MABR membrane aeration in the aeration stage adopts a pulse aeration mode, the aeration time is 40 min, the stop time is 20 min, the gas supply pressure is controlled in the range of 17-22 KPa, and the reaction time is controlled in the range of 1.5-2.5 h; when the nitrate nitrogen removal rate is higher than 80% and the continuous stable operation is more than 7 days, the aeration time is adjusted to 30 min, the stop time is 30 min, the gas supply pressure is controlled in the range of 19-24 KPa, and the reaction time is 1.0-2.0 h, and long-term operation is carried out under the above conditions; in the aerobic section MABR tank, the MABR membrane aeration in the aeration stage adopts a pulse aeration mode, the aeration time is 40 min, the stop time is 20 min, the gas supply pressure is controlled in the range of 22-27 KPa, and the reaction time is controlled in the range of 3.0-7.0 h; when the ammonia nitrogen removal rate is higher than 80% and the continuous stable operation is more than 7 days, the aeration time is adjusted to 30 min, the stop time is 30 min, the gas supply pressure is controlled in the range of 24-29 KPa, and the reaction time is 2.0-6.0 h, and long-term operation is carried out under the above conditions.