Continuous flow aoa process technology method and device for rapid start-up of short-cut nitrification and anoxic ammonia oxidation based on anaerobic starvation and intermittent aeration

Abstract

The continuous flow AOA process technical method and device based on anaerobic starvation and intermittent aeration for rapid start-up of short-cut nitrification and anaerobic ammonia oxidation belong to the field of wastewater biological treatment. The device comprises a water inlet tank, a continuous flow AOA reactor and a secondary sedimentation tank. Raw water is first pumped into the anaerobic zone by a water inlet pump for storage of internal carbon source, and then enters the aerobic zone to rapidly start up short-cut nitrification through anaerobic starvation, realize NO2 ‑ accumulation in the aerobic zone, and then start up intermittent aeration to jointly maintain stable short-cut nitrification, NO2 ‑ accumulation reaches a certain concentration, fluidized anaerobic ammonia oxidation filler is added, the time difference characteristics of intermittent aeration are utilized, short-cut nitrification is carried out during the aeration period of intermittent aeration, and anaerobic ammonia oxidation is carried out during the non-aeration period, so that one-stage short-cut nitrification coupled with anaerobic ammonia oxidation is formed in the aerobic zone, and finally internal source denitrification is carried out in the anoxic zone by using the stored internal carbon source to realize deep denitrification. The present application fully utilizes carbon source, saves aeration energy consumption and has less sludge yield, thereby saving cost.

Description

TECHNICAL FIELD

[0001] The present application relates to a continuous flow AOA process technology method and device based on anaerobic starvation and intermittent aeration for rapid start-up of short-cut nitrification and anaerobic ammonia oxidation, belonging to the field of biological wastewater treatment and resource consumption reduction rationalization. It has the advantages of deep denitrification and phosphorus removal, reduced energy consumption and sludge production, etc., and is suitable for technical fields such as municipal wastewater treatment plants. BACKGROUND

[0002] In recent years, with the rapid development of society, the treatment of urban wastewater is increasingly pursuing efficient, green and energy-saving. The increasingly high emission standards make it difficult for traditional wastewater treatment technologies to meet the demand, so new technologies that are energy-saving and environmentally friendly need to be developed. As a new type of denitrification process, short-cut nitrification coupled with anaerobic ammonia oxidation has the advantages of reducing aeration energy consumption and reducing dosing costs. One-stage coupling can shorten the overall reaction time and save space by reasonably utilizing the arrangement sequence in time and space. Through the combination with autotrophic biological denitrification technology, the effect of low energy consumption and high efficiency is achieved. Subsequently, anaerobic ammonia oxidation can be further coupled in the anoxic section, which has great potential for improvement.

[0003] Compared with the traditional A 2 O operation mode, the AOA operation mode makes full use of and does not require external carbon source, saving digestion liquid reflux, and is more simple and convenient in operation. Compared with the traditional nitrification / denitrification process, short-cut nitrification / denitrification can save 40% of carbon source and 25% of aeration energy consumption, and coupling anaerobic ammonia oxidation can save 100% of carbon source and 60% of aeration amount. Since there is no natural NO2 - -N supply in urban wastewater, short-cut nitrification is needed to provide NO2 - -N substrate for anaerobic ammonia oxidation, and an important part of short-cut nitrification is the inhibition of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) to different degrees according to their characteristics, which promotes the growth of AOB and inhibits NOB. The current methods for achieving short-cut nitrification mainly include the following: low dissolved oxygen, high temperature, ammonia nitrogen surplus, low sludge age, toxic inhibition (free nitrous acid FNA, free ammonia FA), starvation treatment, intermittent aeration, addition of hydroxylamine, real-time control, etc.

[0004] Starvation treatment refers to placing sludge in a water body without organic matter supply for a period of time, so that microorganisms living in the sludge cannot absorb sufficient organic matter, and then fall into a "starvation" state. Subsequently, normal organic matter supply is restored, and a short-term nitrite accumulation state occurs at the beginning of sewage treatment, but then short-cut nitrification is destroyed and cannot be maintained for a long time. Through the strategy of intermittent aeration, according to the difference in activity recovery of NOB and AOB, the activity of NOB is selectively inhibited, but there are still problems such as slow start and instability in continuous flow. Intermittent aeration can provide aerobic and anoxic states in time for the same grid chamber, nitritation is carried out in the aerobic state, and anoxic ammonia oxidation is facilitated in the anoxic state, so as to form a one-stage short-cut nitrification coupled with anoxic ammonia oxidation system in the continuous flow aerobic grid chamber.

[0005] Therefore, for the treatment of low-temperature, low-C / N and large water quality fluctuation municipal sewage, more carbon source needs to be added, the efficiency is low, it is difficult to start quickly, and the effluent is not easy to meet the standard when the water quality fluctuates. A strategy based on starvation treatment combined with intermittent aeration is proposed, and a one-stage treatment is formed by coupling anoxic ammonia oxidation, so as to realize efficient and stable deep denitrification of low-C / N municipal sewage in AOA continuous flow process. SUMMARY

[0006] Based on the current problems of insufficient carbon source, difficulty in starting short-cut nitrification, difficulty in enriching anoxic ammonia oxidation bacteria, and difficulty in achieving deep denitrification in continuous flow treatment of low-C / N domestic sewage, a continuous flow AOA process technical method and device based on anaerobic starvation and intermittent aeration for rapid start-up of short-cut nitrification and anoxic ammonia oxidation are proposed.

[0007] The continuous flow AOA process technical method and device based on anaerobic starvation and intermittent aeration for rapid start-up of short-cut nitrification and anoxic ammonia oxidation, characterized in that: the whole includes a sewage inlet water tank (1), a continuous flow AOA reactor (2), and a secondary sedimentation tank (3).

[0008] The AOA reactor (2) comprises 8 compartments, which are divided into 2 anaerobic compartments, 3 aerobic compartments and 3 anoxic compartments in the water flow direction. The first two compartments are fixed compartments, and the last six compartments are separated by movable plugboards. Adjacent compartments are connected through up-and-down staggered water passing holes to prevent short-circuiting. The water inlet tank (1) is connected to the first anaerobic compartment (2.1) of the AOA reactor (2) through a water inlet pipe (1.1) and a water inlet pump (1.2). The first compartment (2.1) and the second compartment (2.2) are anaerobic zones, the third compartment (2.3), the fourth compartment (2.4) and the fifth compartment (2.5) are aerobic zones, and the sixth compartment (2.6), the seventh compartment (2.7) and the eighth compartment (2.8) are anoxic zones. The eighth anoxic compartment (2.8) is connected to the secondary sedimentation tank (3) through a water outlet pipe (2.10). The sludge in the sludge hopper of the secondary sedimentation tank (3) is returned to the first anaerobic zone (2.1) and the first anoxic zone (2.6) through a sludge return pump (3.1) and a sludge return pipe (3.2), respectively. The remaining sludge in the secondary sedimentation tank is discharged through a remaining sludge pipe (3.3), and the effluent of the secondary sedimentation tank is discharged through a water outlet pipe (3.4). The third compartment (2.3), the fourth compartment (2.4) and the fifth compartment (2.5) in the aerobic zone are provided with suspended fillers (2.13). Intermittent aeration is carried out by an aeration pump (2.11) through an aeration pipe (2.11.1) and an aeration surface aerator (2.11.2). Each aeration surface aerator is connected to a rotor flow meter (2.11.3). Each compartment in the AOA reactor (2) is provided with a stirrer (2.9), and the third compartment (2.3), the fourth compartment (2.4) and the fifth compartment (2.5) in the aerobic zone are provided with small blade stirring paddles (2.12) with a width of 6 cm and a length of 20 cm. WTW probes are arranged in each aerobic compartment of the AOA reactor (2) to monitor the dissolved oxygen in the aerobic zone.

[0009] The treatment process of municipal domestic sewage in the process is as follows: domestic sewage is first pumped into the anaerobic compartment from the water inlet tank through the water inlet pump. In the anaerobic compartment, the available organic matter in the sewage is absorbed into the cells as internal carbon source PHA through the action of denitrifying poly-sugar bacteria (DPAOs) and denitrifying poly-phosphorus bacteria (DPAOs). Then the mixed liquid enters the aerobic compartment, and short-term starvation treatment is carried out to inhibit nitrite oxidizing bacteria (NOB) and promote the growth of ammonia oxidizing bacteria (AOB). The process is maintained by intermittent aeration. During the aeration process, NH4 + is oxidized to NO2 - under the action of AOB. Then, in the non-aeration process of intermittent aeration, the remaining NH4 + in the sewage reacts with the generated NO2 - on the filler to produce N2 and NO3 -, the DPAOs are discharged for phosphorus removal, and finally enter the anoxic compartment, the DGAOs use the internal carbon source stored in the anaerobic compartment as the carbon source, and the remaining small amount of NO2 - and NO3 - as electron acceptors to perform endogenous denitrification, completely remove nitrogen, and achieve deep denitrification effect.

[0010] The present application is based on the continuous flow AOA process technology method and device for quickly starting up short-cut nitrification and anaerobic ammonia oxidation by anaerobic starvation and intermittent aeration, which comprises the following steps:

[0011] 1) Anaerobic starvation to start up short-cut nitrification stage: inoculate the traditional full nitrification and denitrification residual sludge in the secondary sedimentation tank of the A 2 O process as experimental sludge into the AOA reactor (2). Keep the sludge concentration in the reactor between 4000-5500 mg / L; stop the water in and out after the reactor is filled with domestic wastewater, so that the hydraulic retention time tends to be infinite, no aeration is needed in the aerobic zone, and the dissolved oxygen is less than 0.10 mg / L; then adjust the hydraulic retention time to 16 hours to enter the bacterial recovery stage, inhibit and wash the NOB; the sludge return adopts a double return mode, and is returned to the first compartment (2.1) of the anaerobic zone and the first compartment (2.6) of the anoxic zone respectively, and the return ratio is set to 100%; the total hydraulic retention time is 16h, and the sludge age is 15-25d. In this stage, when the nitrite accumulation rate (NAR) in the last compartment (2.5) of the aerobic zone, i.e. the ratio of the nitrite concentration to the sum of the nitrite and nitrate concentrations, reaches more than 80%, and the maintenance time reaches more than 7d, it is considered that the short-cut nitrification is initially successfully started up, and then the next stage is entered.

[0012] 2) Short-cut nitrification maintenance stage: after the short-cut nitrification is quickly started up by aerobic starvation, the aerobic zone starts aeration, the aeration mode is intermittent aeration, the aeration time is 20 min, the non-aeration time is 20 min, one cycle is 40 min, and the system runs continuously for 24h, the total hydraulic retention time of the aerobic aeration is 3h, the aeration mode adopts three compartments to be aerated and paused at the same time, so that the dissolved oxygen gradually rises and is finally controlled at 1.0-1.5 mg / L during the aeration period, and the dissolved oxygen decreases and is maintained at 0.05-0.10 mg / L during the non-aeration period. Through the AOA operation, the "anaerobic-anoxic-aerobic" mode forms intermittent aeration in space, and the intermittent aeration in time is realized through the intermittent aeration of the aerobic O section of the AOA, so as to be combined into "double" intermittent aeration. During the non-aeration period, the activities of the NOB and the AOB are synchronously reduced, after the aeration is restored, the difference between the activities of the AOB and the NOB is further expanded through the different recovery abilities of the AOB and the NOB, the stability of the short-cut nitrification is maintained, the NAR in the aerobic section is maintained at more than 90% and reaches more than 30d, it is considered that the short-cut nitrification is stably maintained, and then the next stage is entered.

[0013] 3) One-stage short-cut nitrification coupled with anaerobic ammonia oxidation start-up phase: after stable maintenance of short-cut nitrification, fluidized blank fillers are put into the aerobic zone of the AOA reactor (2), and the filler filling ratio is 25%; in this phase, the NO2 - occurs anaerobic ammonia oxidation reaction, and the fillers are self-enriched with anaerobic ammonia oxidation bacteria; the municipal domestic sewage is stored with internal carbon source in the anaerobic zone of the AOA reactor, and then enters the aerobic zone; according to the different states of aeration and non-aeration in different time periods, the short-cut nitrification and the coupling of anaerobic ammonia oxidation reaction are carried out in different time periods, the state difference in time is ingeniously utilized to efficiently remove nitrogen in the same space, and the aerobic zone is promoted to become a denitrification hot zone; the NO3 + and NO2 - are removed in the anoxic zone, and the internal carbon source stored in the anaerobic zone is used for endogenous denitrification. - When the organic matter removal rate of the AOA reactor (2) reaches 85% or more, the total nitrogen removal rate reaches 90% or more and is maintained for 7 days or more, it is considered that the continuous flow AOA process device based on anaerobic starvation and intermittent aeration is successfully started up, and then enters the next phase.

[0014] 4) Stable operation phase: the sludge in the secondary sedimentation tank (3) is returned to the first compartment (2.1) of the anaerobic zone at 100%, and is returned to the first compartment (2.6) of the anoxic zone at 100%, so as to maintain the average sludge concentration of the AOA reactor (2) at 4000-5500 mg / L, the hydraulic retention time is 16 h, and the sludge age is 15-25 d; the reactor is continuously and long-time operated, the water quality of the secondary sedimentation tank effluent (3.4) is stably within the range of COD≤40 mg / L, NH4 + -N≤2 mg / L and TN≤10 mg / L, which meets the national first-level A discharge standard, and the system reaches a stable state and continues to operate within the standard range. Finally, the process achieves the optimal treatment effect of fully utilizing carbon source, saving aeration energy consumption and deep denitrification.

[0015] Compared with the prior art, the present application has the following advantages:

[0016] (1) The operation mode of the AOA omits sludge return, the internal carbon source storage of DGAOs is carried out in the pre-anoxic section, the original water carbon source is fully utilized, and resources are fully utilized and waste is reduced.

[0017] (2) In the continuous flow process, the short-cut nitrification is rapidly started up through anaerobic starvation, and is maintained through intermittent aeration, which greatly reduces the aeration energy consumption and provides a stable NO2 - source, provides a stable substrate source for the continuous operation of anaerobic ammonia oxidation, and shortens the start-up time of the overall short-cut nitrification and speeds up the start-up.

[0018] (3) The aerobic compartment is coupled with one-stage short-cut nitrification and anammox by adding fluidized packing. The characteristics of intermittent aeration are used to carry out two different denitrification processes at different time periods, fully utilize the reactor space, and achieve higher nitrogen removal efficiency.

[0019] (4) The post-anoxic compartment can remove a small amount of residual NO3 - and NO2 - in the reactor environment through endogenous denitrification, achieve deep denitrification effect, and further couple anammox by adding packing, which has a broad development prospect. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The structure diagram of the continuous flow AOA process technology and device based on anoxic starvation and intermittent aeration for rapid start-up of short-cut nitrification and anammox.

[0021] Figure 1 1 is the water inlet tank, 1.1 is the water inlet pipe, 1.2 is the water inlet pipe, 2 is the AOA reactor, 2.1-2.2 is the anoxic compartment, 2.3-2.5 is the aerobic compartment, 2.6-2.8 is the anoxic compartment, 2.9 is the agitator, 2.10 is the water outlet pipe, 2.11 is the aeration pump, 2.11.1 is the aeration pipe, 2.11.2 is the aeration face bread aeration disc, 2.11.3 is the rotor flowmeter, 3 is the secondary sedimentation tank, 3.1 is the sludge return pump, 3.2 is the sludge return pipe, 3.3 is the excess sludge pipe, and 3.4 is the water outlet pipe. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. A continuous flow AOA process technology method and apparatus based on rapid start-up of short-cut nitrification and anaerobic ammonia oxidation using anaerobic starvation and intermittent aeration is characterized by: the whole comprising a wastewater inlet tank (1), a continuous flow AOA reactor (2), and a secondary sedimentation tank (3). The AOA reactor (2) includes 8 compartments, divided into 2 anaerobic compartments, 3 aerobic compartments, and 3 anoxic compartments according to the water flow direction. The first two compartments are fixed compartments, and the last six compartments are separated by movable inserts. Adjacent compartments are connected by staggered water passages to prevent backflow and short-circuiting. The inlet tank (1) is connected to the first anaerobic compartment (2.1) of the AOA reactor (2) via an inlet pipe (1.1) and an inlet pump (1.2). 1) The second compartment (2.2) is the anaerobic zone, the third compartment (2.3), the fourth compartment (2.4) and the fifth compartment (2.5) are the aerobic zones, and the sixth compartment (2.6), the seventh compartment (2.7) and the eighth compartment (2.8) are the anoxic zones. The anoxic compartment (2.8) is connected to the secondary sedimentation tank (3) through the effluent pipe (2.10). The sludge in the sludge hopper of the secondary sedimentation tank (3) is returned to the sludge hopper through the sludge return pump (3.1) and the sludge return pipe (3.2). The sludge flows into the first compartment of the anaerobic zone (2.1) and the first compartment of the anoxic zone (2.6). The remaining sludge from the secondary sedimentation tank is discharged through the remaining sludge pipe (3.3), and the effluent from the secondary sedimentation tank is discharged through the effluent pipe (3.4). The third compartment (2.3), fourth compartment (2.4), and fifth compartment (2.5) of the aerobic zone contain suspended packing material (2.13). Aeration is achieved using an aeration pump (2.11) through an aeration pipe (2.11.1) and an aeration tray (2.11). 2) Intermittent aeration is performed, and each aeration bread pan is connected to a rotor flow meter (2.11.3); each compartment of the AOA reactor (2) is equipped with a stirrer (2.9), and the third compartment (2.3), fourth compartment (2.4), and fifth compartment (2.5) of the aerobic zone are equipped with small blade stirring paddles (2.12) with a width of 6cm and a length of 20cm; each aerobic compartment of the AOA reactor (2) is equipped with a WTW probe to monitor dissolved oxygen in the aerobic zone.

[0023] Taking the septic tank wastewater from a university residential area in Beijing as the treatment target, the specific water quality during operation was as follows: COD 180-280 mg / L, NH4+ + -N is 70-80 mg / L, NO3 - -N≤2mg / L, NO2 - -N≤0.5mg / L. The test system is as follows: Figure 1 As shown, the intermittent aeration coupled with a single-stage short-cut nitrification / anaerobic ammonia oxidation modified AOA reactor for deep denitrification of low C / N urban wastewater has an effective volume of 46.1L, divided into 8 compartments. The secondary sedimentation tank has an effective volume of 20.4L, and both are made of acrylic sheets.

[0024] The specific steps are as follows:

[0025] 1) Anaerobic starvation to start up partial nitrification phase: Inoculation of municipal wastewater treatment plant A 2 The traditional full nitrification-denitrification residual sludge in the secondary sedimentation tank of the O process was used as the experimental sludge and placed in the AOA reactor (2). The sludge concentration in the reactor was maintained at 4000-5500 mg / L; the reactor was filled with domestic wastewater and the water inflow and outflow were stopped so that the hydraulic retention time tended to be infinite, and the dissolved oxygen in the aerobic zone was less than 0.10 mg / L. Then, the hydraulic retention time was adjusted to 16 hours to enter the bacterial recovery phase to inhibit and wash the NOB; the sludge reflux was in a double reflux mode and was refluxed to the first compartment (2.1) of the anaerobic zone and the first compartment (2.6) of the anoxic zone, respectively, and the reflux ratio was set to 100%; the total hydraulic retention time was 16 h and the sludge age was 15-25 d. In this phase, when the nitrite accumulation rate (NAR) in the effluent of the last compartment (2.5) of the aerobic zone, i.e., the ratio of the nitrite concentration to the sum of the nitrite and nitrate concentrations, reached more than 80% and was maintained for more than 7 d, it was considered that the partial nitrification was initially successfully started, and then the next phase was entered.

[0026] 2) Partial nitrification maintenance phase: After the partial nitrification was rapidly started by aerobic starvation, the aerobic zone was aerated, the aeration mode was intermittent aeration, the aeration time was 20 min, the non-aeration time was 20 min, one cycle was 40 min, and the reactor was continuously operated for 24 h. The total hydraulic retention time of the aerobic aeration was 3 h, the aeration mode was three compartments simultaneously aerated and simultaneously stopped, and the dissolved oxygen was gradually increased and finally controlled at 1.0-1.5 mg / L during the aeration period, and the dissolved oxygen was decreased and maintained at 0.05-0.10 mg / L during the non-aeration period. Through the AOA operation, the "anaerobic-anoxic-aerobic" mode formed intermittent aeration in space, and the intermittent aeration in time was realized through the intermittent aeration of the aerobic O section in the AOA, thereby forming "double" intermittent aeration. During the non-aeration period, the activities of the NOB and the AOB were simultaneously reduced, and after the aeration was restored, the difference between the activities of the AOB and the NOB was further expanded by the different recovery abilities of the AOB and the NOB, thereby maintaining the stability of the partial nitrification, and the NAR in the aerobic section was maintained at more than 90% and reached more than 30 d, which indicated that the partial nitrification was stably maintained, and then the next phase was entered.

[0027] 3) One-stage partial nitrification coupled with anaerobic ammonia oxidation start-up phase: After the partial nitrification was stably maintained, the fluidized blank filler was added to the aerobic zone of the AOA reactor (2), and the filler filling ratio was 25%; in this phase, the NO2 - and the residual NH4 +anaerobic ammonium oxidation reaction, and anaerobic ammonium oxidation bacteria are self-enriched on the filler; municipal domestic sewage is stored with internal carbon source in the anaerobic zone of the AOA reactor, and then enters the aerobic zone; according to the different states of aeration and non-aeration in different time periods, short-cut nitrification and coupling of anaerobic ammonium oxidation reaction are carried out in different time periods, time state difference in the same space is ingeniously utilized for efficient denitrification, and the aerobic zone is promoted to become a denitrification hot zone; the residual NO3 - and NO2 - are removed by internal source denitrification using the carbon source stored in the anaerobic zone. When the organic matter removal rate of the AOA reactor (2) is 85% or more, the total nitrogen removal rate is 90% or more, and the above conditions are maintained for 7 days or more, it is considered that the continuous flow AOA process device based on rapid start-up of short-cut nitrification and anaerobic ammonium oxidation by anaerobic starvation and intermittent aeration is successfully started, and then enters the next stage.

[0028] 4) Stable operation stage: the sludge in the secondary sedimentation tank (3) is returned to the first compartment (2.1) of the anaerobic zone at 100%, and is returned to the first compartment (2.6) of the anoxic zone at 100%, so as to maintain the average sludge concentration of the AOA reactor (2) at 4000-5500 mg / L, the hydraulic retention time is 16 h, and the sludge age is 15-25 d; the reactor is continuously and long-term operated, and the water quality of the secondary sedimentation tank effluent (3.4) is stable in the range of COD≤40 mg / L, NH4 + -N≤2 mg / L, and TN≤10 mg / L, which meets the national first-level A discharge standard, and it is considered that the system reaches a stable state and continues to operate within the standard range. Finally, the process achieves the advantages of full utilization of carbon source, saving of aeration energy consumption, and high-quality treatment effect of deep denitrification.

[0029] The experimental results show that after the reactor is stably operated, the COD of the effluent of municipal low C / N domestic sewage treated by the continuous flow AOA process technology and device based on rapid start-up of short-cut nitrification and anaerobic ammonium oxidation by anaerobic starvation and intermittent aeration is 30-40 mg / L, NH4 + -N is less than 2 mg / L, NO3 - -N is less than 5 mg / L, NO2 - -N is less than 0.5 mg / L, and total nitrogen is less than 10 mg / L, and the indexes such as effluent COD, NH4 + -N, and TN all stably meet the national first-level A discharge standard for sewage treatment.

[0030] The above is a specific implementation case of the experiment, which facilitates better understanding and application of the present application by the technicians in the technical field, but the implementation of the present application is not limited thereto, and therefore the simple improvements of the present application made by the technicians in the technical field are within the protection scope of the present application.

Claims

1. A continuous flow AOA method for rapid start-up of short-cut nitrification and anaerobic ammonium oxidation based on anaerobic starvation and intermittent aeration, characterized by: The apparatus used in this method includes a wastewater inlet tank (1), a continuous flow AOA reactor (2), and a secondary sedimentation tank (3). The AOA reactor (2) consists of 8 compartments, which are divided into 2 anaerobic compartments, 3 aerobic compartments, and 3 anoxic compartments according to the water flow direction. The first two compartments are fixed, and the last six compartments are separated by movable baffles. Adjacent compartments are connected by staggered water passages to prevent backflow and short-circuiting. The wastewater inlet tank (1) is connected to the AOA reactor (2) via an inlet pipe (1.1) and an inlet pump (1.2). The first compartment (2.1) of reactor A (2) is connected, where the first compartment (2.1) and the second compartment (2.2) are anaerobic zones, the third compartment (2.3), the fourth compartment (2.4) and the fifth compartment (2.5) are aerobic zones, and the sixth compartment (2.6), the seventh compartment (2.7) and the eighth compartment (2.8) are anoxic zones. The eighth compartment (2.8) is connected to the secondary sedimentation tank (3) through the effluent pipe (2.10). The sludge in the sludge hopper of the secondary sedimentation tank (3) is pumped back by the sludge return pump (3.1). The sludge is returned to the first compartment (2.1) of the anaerobic zone and the sixth compartment (2.6) of the anoxic zone via the sludge return pipe (3.2). The excess sludge from the secondary sedimentation tank is discharged through the excess sludge pipe (3.3), and the effluent from the secondary sedimentation tank is discharged through the effluent pipe (3.4). The third compartment (2.3), fourth compartment (2.4), and fifth compartment (2.5) of the aerobic zone contain fluidized blank suspended packing material (2.13). Aeration is achieved by an aeration pump (2.11) through the aeration pipe (2.11.1) and the aeration pump. The bread aeration discs (2.11.2) are used for intermittent aeration, and each aeration bread aeration disc is connected to a rotor flow meter (2.11.3); each compartment of the AOA reactor (2) is equipped with a stirrer (2.9), and the third compartment (2.3), fourth compartment (2.4), and fifth compartment (2.5) of the aerobic zone are equipped with small blade stirrers (2.12) with a width of 6cm and a length of 20cm; each compartment of the aerobic zone of the AOA reactor (2) is equipped with a WTW probe to monitor the dissolved oxygen in the aerobic zone; The method includes the following steps: 1) Anaerobic starvation initiation of short-cut nitrification stage: Inoculation of municipal wastewater treatment plant A 2 The residual sludge from the traditional full-process nitrification and denitrification in the secondary sedimentation tank of the O process was used as experimental sludge and placed in the AOA reactor (2). The sludge concentration in the reactor was kept between 4000 and 5500 mg / L. After the reactor was filled with municipal sewage, the influent and effluent were stopped. The dissolved oxygen was less than 0.10 mg / L, and then the bacterial recovery stage was entered to inhibit and wash the nitrifying bacteria. The sludge was returned in a dual return mode, and returned to the first compartment (2.1) of the anaerobic zone and the sixth compartment (2.6) of the anoxic zone respectively. The return ratio of both was 100%. In this stage, the nitrite accumulation rate (NAR) in the effluent of the fifth compartment (2.5) of the aerobic zone, that is, the ratio of nitrite concentration to the sum of nitrite and nitrate nitrogen concentration, reached more than 80% and was maintained for more than 7 days. This was considered as the initial success of the short-cut nitrification start-up, and then the next stage was entered. 2) Short-cut nitrification maintenance stage: After rapid initiation of short-cut nitrification through anaerobic starvation, aeration begins in the aerobic zone. The aeration method is intermittent aeration, with an aeration time of 20 minutes and a non-aeration time of 20 minutes, for a total of 40 minutes per cycle. It operates continuously for 24 hours a day, with a total hydraulic retention time of 3 hours. The aeration mode adopts simultaneous aeration and pausing in three compartments to ensure that dissolved oxygen gradually rises during aeration and is eventually controlled at 1.0-1.5 mg / L. During non-aeration, dissolved oxygen decreases and remains at 0.05-0.10 mg / L. The stability of short-cut nitrification is maintained through the intermittent aeration operation of the AOA reactor. When the NAR in the aerobic zone is maintained above 90% for more than 30 days, it is considered that short-cut nitrification has been stably maintained, and then the next stage begins. 3) Start-up stage of short-cut nitrification coupled with anaerobic ammonium oxidation: After the short-cut nitrification is stabilized, fluidized blank suspended packing is added to the aerobic zone of the AOA reactor (2), with a packing ratio of 25%; during this stage, the anaerobic zone stores the internal carbon source; the aeration-to-stop ratio in the aerobic zone is maintained at 20 min: 20 min, and the short-cut nitrification process is carried out during the aeration period to provide substrate NO2 for anaerobic ammonium oxidation. - During non-aeration periods, NO2 - With the remaining NH4 + Anaerobic ammonia oxidation occurs, and anaerobic ammonia-oxidizing bacteria accumulate on the packing material; the anoxic zone reacts with the NO3 remaining after the aerobic zone's reaction. - With NO2 - Denitrification is carried out using internal carbon sources. When the organic matter removal rate of the AOA reactor (2) reaches 85% or more and the total nitrogen removal rate reaches 90% or more and is maintained for 7 days or more, it is considered that the continuous flow AOA device based on anaerobic starvation and intermittent aeration for rapid start-up of short-cut nitrification and anaerobic ammonia oxidation has been successfully started and then enters the next stage. 4) Stable operation phase: The reactor operates continuously, with influent being municipal domestic sewage, COD of 180-280 mg / L, and NH4+. + -N is 70-80 mg / L, NO3 - -N≤2mg / L, NO2 - -N≤0.5mg / L, wastewater enters the anaerobic zone to store internal carbon sources. In the aerobic zone, nitrogen is removed through intermittent aeration, with a 20-minute aeration followed by a 20-minute pause, for a total cycle of 40 minutes. Dissolved oxygen is controlled at 1.0-1.5mg / L during aeration and below 0.1mg / L during non-aeration periods. Wastewater then enters the anoxic zone for internal carbon source denitrification. The wastewater has a residence time of 16 hours in the reactor and finally exits through a triangular weir into the secondary sedimentation tank. All sludge from the secondary sedimentation tank is 100% recycled to the first compartment of the anaerobic zone and the sixth compartment of the anoxic zone, respectively, to ensure that the sludge concentration in the reactor is maintained at 4000-5500mg / L.

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