AOA denitrification apparatus and method

Abstract

The present application belongs to the field of sewage treatment, and particularly relates to an AOA denitrification device and method. The device comprises a water inlet tank and a continuous flow AOA reactor; the continuous flow AOA reactor comprises an anaerobic zone, an aerobic zone, a first sedimentation zone, an anoxic zone and a second sedimentation zone in sequence; the water inlet tank is connected with the pipeline of the anaerobic zone of the continuous flow AOA reactor; a first stirrer and a three-phase separator are arranged in the anaerobic zone; an aeration assembly is arranged in the aerobic zone; a second stirrer and a carbon source feeding device are arranged in the anoxic zone. The AOA denitrification device and method creatively apply core technologies such as short-cut nitrification and anaerobic ammonia oxidation to the treatment of high-ammonia-nitrogen wastewater, realize the combination of short-cut nitrification, anaerobic ammonia oxidation and denitrification, solve the problems of large carbon source feeding amount and excessive carbon emission in the traditional denitrification process, reduce the cost, and at the same time solve the problem of total nitrogen exceeding the standard in the effluent of the anaerobic ammonia oxidation method.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of sewage treatment, and particularly relates to an AOA denitrification device and method. BACKGROUND

[0002] Generally, the concentration of pollutants in sewage is low, and the nutrient ratio is normal, so the denitrification can be carried out by the nitrification-denitrification method. However, some wastewater with low carbon-nitrogen ratio and high ammonia nitrogen concentration is inevitably produced in human industrial activities. If the traditional nitrification-denitrification method is used for denitrification, a large amount of carbon source needs to be added to complete the denitrification process, which causes waste of resources and aggravates carbon emission. Therefore, it is urgent to develop a new type of green and efficient denitrification system. SUMMARY

[0003] In view of the problems in the prior art, one of the purposes of the present application is to provide an AOA denitrification device, which has a simple structure and can realize the combination of short-cut nitrification, anaerobic ammonia oxidation and denitrification, thereby solving the problems of large carbon source addition amount and excessive carbon emission in the traditional denitrification process.

[0004] The second purpose of the present application is to provide an AOA denitrification method.

[0005] To achieve the purposes of the present application, the specific technical solutions are as follows:

[0006] An AOA denitrification device comprises a water inlet tank and a continuous flow AOA reactor; the continuous flow AOA reactor comprises an anaerobic zone, an aerobic zone, a first sedimentation zone, an anoxic zone and a second sedimentation zone which are sequentially connected; the water inlet tank is connected with a pipeline of the anaerobic zone of the continuous flow AOA reactor;

[0007] A first stirrer and a three-phase separator are arranged in the anaerobic zone; an aeration assembly is arranged in the aerobic zone; a second stirrer and a carbon source adding device are arranged in the anoxic zone; a first reflux pipeline is arranged in the anaerobic zone, a second reflux pipeline is arranged between the first sedimentation zone and the aerobic zone, a third reflux pipeline is arranged in the anoxic zone, and a fourth reflux pipeline is arranged between the second sedimentation zone and the anoxic zone; and a fifth reflux pipeline is arranged between the first sedimentation zone and the water inlet tank.

[0008] Preferably, the anaerobic zone comprises a first anaerobic chamber and a second anaerobic chamber which are sequentially connected with the water inlet tank, the first stirrer is arranged in the first anaerobic chamber, and the three-phase separator is arranged in the second anaerobic chamber; and a first reflux pipeline is arranged between the second anaerobic chamber and the first anaerobic chamber.

[0009] Preferably, the aerobic zone comprises a first aerobic chamber and a second aerobic chamber which are sequentially connected with the anaerobic zone, and the first aerobic chamber and the second aerobic chamber are respectively provided with an aeration assembly.

[0010] Preferably, a second reflux pipeline is arranged between the first sedimentation zone and the aerobic zone.

[0011] Preferably, the anoxic zone comprises a first anoxic chamber and a second anoxic chamber which are sequentially communicated with the first sedimentation zone, the carbon source adding device is arranged in the first anoxic chamber, and a third reflux pipeline is arranged between the second anoxic chamber and the first anoxic chamber.

[0012] Preferably, a fourth reflux pipeline is arranged between the second sedimentation zone and the anoxic zone, and the fourth reflux pipeline is communicated with the carbon source adding device through a tee joint.

[0013] Preferably, the aeration assembly comprises an aeration disc, a flow meter and an aeration pump.

[0014] Preferably, the carbon source adding device comprises a carbon source water distribution tank and a carbon source adding pump.

[0015] Preferably, the second reflux pipeline is communicated with a first aerobic chamber of the aerobic zone.

[0016] Preferably, the third reflux pipeline is communicated with a second anoxic chamber of the anoxic zone.

[0017] The application further discloses a treatment method of nitrogen-containing wastewater, using the AOA denitrification device, comprising the following steps:

[0018] 1) Start-up of the system

[0019] Anaerobic ammonium oxidation bacteria are mixed with landfill leachate biochemical treatment anaerobic zone sludge and added to the anaerobic zone;

[0020] Landfill leachate biochemical treatment section aerobic zone sludge is added to the aerobic zone;

[0021] Landfill leachate biochemical treatment anaerobic zone sludge is added to the anoxic zone;

[0022] The sludge concentration of the anaerobic zone, the aerobic zone and the anoxic zone is set to 4000-6000 mg / L;

[0023] The NH4 + The NH4 + The inorganic carbon source is added, the pH is adjusted to 6.3-7.5 by using acid or alkali, and then the raw water and the reflux sludge of the anaerobic zone enter the AOA reactor together;

[0024] In the anaerobic zone, the anaerobic ammonium oxidation reaction occurs, the mud and water are uniformly mixed by the first agitator, and the anaerobic ammonium oxidation sludge is retained in the anaerobic zone by the three-phase separator 212.

[0025] In the aerobic zone, short-term nitrification reaction occurs, and the dissolved oxygen concentration in the aerobic zone is maintained at 0.5-2 mg / L, so as to inhibit nitrite oxidizing bacteria and make ammonia oxidizing bacteria become the dominant bacteria in nitrifying bacteria;

[0026] The effluent of the aerobic zone flows into the first sedimentation zone, part of the supernatant of the first sedimentation zone is refluxed into the water inlet tank, and the sludge of the first sedimentation zone is refluxed into the aerobic zone; the remaining supernatant flows into the anoxic zone, and in the anoxic zone, the carbon source dosage is 100-200 mg / L, and the mixture is stirred uniformly;

[0027] The effluent of the anoxic zone flows into the second sedimentation zone, the sludge of the second sedimentation zone is refluxed into the anoxic zone, and the effluent of the second sedimentation zone is discharged;

[0028] The start-up of the system includes multiple stages, and the system is started in stages, and the hydraulic retention time of each stage is gradually reduced until each stage meets the following requirements:

[0029] The NH4 + -N, NO2 - -N, NO3 - -N concentration in the effluent of the aerobic zone is less than 10 mg / L and is maintained for more than one week, the system start-up is successful; - -N accumulation, NH4 + -N conversion rate is greater than 80%, NO2 - -N accumulation rate is greater than 70% and is stable for more than one week, the system can enter the next start-up stage;

[0030] When operating to the last stage, when the NO2 - -N concentration in the effluent of the anoxic zone is less than 10 mg / L and is maintained for more than one week, the system start-up is successful;

[0031] 2) System operation

[0032] The raw water with an NH4 + -N concentration of 800-1400 mg / L is mixed with the refluxed nitrification liquid of the first sedimentation zone in the water inlet tank, so that the NH4 + -N concentration of the wastewater in the water inlet tank is 400-600 mg / L, the NO2 - -N concentration is 100-200 mg / L, and an inorganic carbon source is added, and the pH is adjusted to 6.3-7.5 with acid or alkali, and the refluxed sludge of the anoxic zone is entered into the AOA reactor together;

[0033] In the anoxic zone, anaerobic ammonia oxidation reaction occurs, the mud and water are mixed by the first stirrer, and the anaerobic ammonia oxidation sludge is retained in the anoxic zone by the three-phase separator;

[0034] In the aerobic zone, the aeration amount is controlled, and the NH4 +-N is oxidized to NO2 - -N and NO3 - -N;

[0035] The effluent enters the first sedimentation zone, where the nitration liquid reflux and the nitration sludge reflux are carried out, and the nitration liquid reflux ratio is 1-2;

[0036] The remaining nitration liquid enters the anoxic zone, where carbon source is added, and sludge reflux in the anoxic zone is carried out.

[0037] The final effluent is discharged from the second sedimentation zone.

[0038] In the starting process of step (1):

[0039] Preferably, 0.5-1 g / L of NaHCO3 is added as an inorganic carbon source; H2SO4 or NaOH is used to adjust the pH to 6.3-7.5.

[0040] Preferably, the dissolved oxygen concentration in the aerobic zone is maintained at 0.5-2 mg / L.

[0041] Preferably, part of the supernatant in the first sedimentation zone is refluxed into the influent tank, and the reflux ratio is controlled at 1-2.

[0042] Preferably, the carbon source addition amount in the anoxic zone is 100-200 mg / L.

[0043] Preferably, when the last stage is operated, the hydraulic retention time is set to 6 h, and the nitrogen removal in the anaerobic ammonia oxidation section of the anaerobic zone is detected, when the NO2 - -N concentration in the effluent of the anaerobic zone is less than 10 mg / L and is maintained for more than one week, the system is successfully started.

[0044] In the running process of step (2):

[0045] Preferably, 0.2-0.7 g / L of NaHCO3 is added as an inorganic carbon source; H2SO4 or NaOH is used to adjust the pH to 6.3-7.5.

[0046] Preferably, the anaerobic ammonia oxidation reaction in the anaerobic zone removes NH4 + -N and NO2 - -N.

[0047] Preferably, the nitration liquid reflux ratio in the first sedimentation zone is 1-2.

[0048] Preferably, in the anoxic zone, the carbon source addition amount is 400-600 mg / L.

[0049] Preferably, in the starting process of step (1): the hydraulic retention time is 6-48 h.

[0050] Further preferably, the start-up process of the system comprises three stages, and the hydraulic retention time of the three stages is 12h, 8h and 6h respectively.

[0051] Preferably, in the final effluent, the concentration of NH4 + The concentration of N is less than 8mg / L, and the concentration of total nitrogen is less than 20mg / L.

[0052] Compared with the prior art, the present application has the beneficial effects of:

[0053] (1) The AOA denitrification device and method of the present application creatively apply short-cut nitrification, anaerobic ammonia oxidation and other core technologies to the treatment of high-ammonia-nitrogen wastewater, realize the combination of short-cut nitrification, anaerobic ammonia oxidation and denitrification, solve the problems of large carbon source dosage and excessive carbon emission in traditional denitrification processes, reduce the cost, and at the same time solve the problem of total nitrogen exceeding the standard in the effluent of the anaerobic ammonia oxidation method.

[0054] (2) Compared with the traditional nitrification-denitrification method, the AOA denitrification device and method of the present application saves 40~60% of oxygen supply and reduces 50~70% of COD demand. BRIEF DESCRIPTION OF DRAWINGS

[0055] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, illustrate the present application and are used to explain the present application together with the embodiments of the present application, and do not constitute a limitation on the present application. In the drawings:

[0056] Figure 1 Figure 1 is a structural schematic diagram of the system of the present application;

[0057] 1 - water inlet tank, 2 - continuous flow AOA reactor, 21 - anaerobic zone, 212 - three-phase separator, 22 - aerobic zone, 221 - aeration disc, 222 - flow meter, 223 - aeration pump, 23 - first sedimentation zone, 24 - anoxic zone, 241 - carbon source water distribution tank, 242 - carbon source dosing pump, 25 - second sedimentation zone, 31 - first stirrer, 32 - second stirrer. DETAILED DESCRIPTION

[0058] In order to facilitate the understanding of the present application, the present application will be described in more detail below in combination with the drawings and preferred embodiments, but the protection scope of the present application is not limited to the following specific embodiments.

[0059] Unless otherwise defined, all professional terms used herein have the same meaning as generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments, and are not intended to limit the protection scope of the present application.

[0060] Unless otherwise specifically indicated, all materials, reagents, solvents, and the like used in the present application are available from commercial vendors or are prepared by conventional methods.

[0061] Example 1

[0062] The present embodiment provides an AOA denitrification device and method.

[0063] Referring to Figure 1 The AOA denitrification device comprises a water inlet tank 1 and a continuous flow AOA reactor 2; the continuous flow AOA reactor 2 comprises an anaerobic zone 21, an aerobic zone 22, a first sedimentation zone 23, an anoxic zone 24, and a second sedimentation zone 25 connected in sequence; the water inlet tank 1 is connected to the anaerobic zone 21 of the continuous flow AOA reactor 2 by a pipeline; a first stirrer 31 and a three-phase separator 212 are arranged in the anaerobic zone 21; an aeration disc 221, a flow meter 222, and an aeration pump 223 are arranged in the aerobic zone 22; a second stirrer 32, a carbon source water distribution tank 241, and a carbon source dosing pump 242 are arranged in the anoxic zone 24; the anaerobic zone 21, the aerobic zone 22, the first sedimentation zone 23, the anoxic zone 24, and the second sedimentation zone 25 are each provided with a backflow pipeline, and a sludge backflow pump is arranged on each backflow pipeline.

[0064] In the present embodiment, mixed backflow digestion liquid and nitrogen-containing wastewater raw water are mixed in the water inlet tank 1, and then the wastewater is introduced into the AOA reactor 2 through the water inlet pump 11 connected to the AOA reactor 2; the sludge is intercepted by the three-phase separator 212 in the anaerobic zone 21 to retain the functional sludge of the anaerobic zone 21, and the sludge in the anaerobic zone 21 is circulated by the sludge backflow pump 211; the aeration pump 223 is connected to the two flow meters 222 in the aerobic zone 22, and the flow meters 222 are connected to the aeration discs 221, respectively, to control the aeration amount in the flow meters 222, thereby controlling the dissolved oxygen concentration in the aerobic zone 22, so that a short-cut digestion reaction occurs in the aerobic zone 22; the sludge in the aerobic zone 22 is precipitated through the first sedimentation zone 23, and the sludge backflow pump 224 connects the first sedimentation zone 23 and the aerobic zone 22 to backflow the sludge, and the nitrification liquid is backflowed by the backflow pump 232 in the first sedimentation zone 23; the carbon source distribution tank 241 and the carbon source dosing pump 242 are arranged in the anoxic zone 24, the carbon source in the carbon source distribution tank 241 is dosed into the anoxic zone 24 by the carbon source dosing pump 242, and the sludge is backflowed by the sludge backflow pump 243 in the second sedimentation zone 25.

[0065] In the present embodiment, the continuous flow AOA reactor 2 in the AOA denitrification device is made of acrylic material, and the total volume of the continuous flow AOA reactor 2 is 20 L, wherein the volumes of the anaerobic zone 21, the aerobic zone 22, and the anoxic zone 24 are 4 L, 4 L, and 6 L, respectively.

[0066] As one of the preferred embodiments of this invention, a method for treating nitrogen-containing wastewater using the above-described device is provided, as follows:

[0067] The water used in the specific experiment was taken from the effluent of the primary sedimentation tank of a landfill leachate membrane concentrate treatment plant in Shenzhen, Guangdong Province. The specific water quality was as follows: COD concentration 1200~1600 mg / L, NH4+ concentration... + -N concentration 1100~1300 mg / L, NO2 - -N concentration 200~500 mg / L, NO3 - -N concentration 0~30mg / L.

[0068] Specifically, the following steps are included:

[0069] (1) System startup

[0070] Anaerobic ammonia-oxidizing bacteria are mixed with sludge from the anaerobic zone of the landfill leachate biochemical treatment and added to the anaerobic zone; sludge from the aerobic zone of the landfill leachate biochemical treatment section is added to the eutrophic zone; and sludge from the anaerobic zone of the landfill leachate biochemical treatment section is added to the anoxic zone. The sludge concentration in each zone is 4000~6000 mg / L.

[0071] Raw water NH4 + With a nitrogen concentration of 1100~1300 mg / L and a total nitrogen concentration of 1100~1500 mg / L, the raw water is mixed with the returned nitrification solution to increase the NH4+ concentration in the influent tank. + The -N concentration is 350~700mg / L, and 0.2~0.7g / L of NaHCO3 is added as an inorganic carbon source. The pH is adjusted to 6.3~7.5 with H2SO4 and NaOH, and then it is fed into the AOA reactor together with the anammox return sludge.

[0072] Anaerobic ammonia-oxidizing bacteria are mainly cultured in the anaerobic zone to carry out the anaerobic ammonia oxidation reaction, producing NH4+. + -N reacts with NO2 under hypoxic or anaerobic conditions. - -N is removed simultaneously. During the process, the mud and water are mixed by a mixer, and the three-phase separator keeps the anaerobic ammonia oxidation sludge in the anaerobic zone. At the same time, the sludge return pump circulates the sludge.

[0073] Remaining NH4 + -N enters the aerobic zone and undergoes short-range nitrification. By controlling the gas flow meter, the dissolved oxygen concentration in the aerobic zone is maintained at 0.5~2mg / L. Micro-aerobic aeration and high free ammonia work together to inhibit nitrite oxidizing bacteria (NOB), so that ammonia oxidizing bacteria (AOB) gradually become the dominant species among nitrifying bacteria.

[0074] The effluent flows into the first sedimentation zone, and part of the supernatant is returned to the inlet tank through the return pump. The return ratio is controlled at 1~2. At the same time, the sludge is also returned to the aerobic zone.

[0075] The remaining supernatant was transferred to the anoxic zone. During the start-up phase, a small amount of carbon source was added to cultivate denitrifying bacteria. The amount of carbon source added was 100-200 mg / L, and the mixture was stirred and mixed thoroughly.

[0076] The effluent flows into the second sedimentation zone, the sludge flows back to the anoxic zone, and the effluent is discharged.

[0077] The overall HRT (hydraulic retention time) is 6–48 hours, and the system is started in three stages, with the HRT gradually reduced. The hydraulic retention times for the three stages are 12 hours, 8 hours, and 6 hours, respectively. NH4 content is measured in each stage. + -N, NO2 - -N, NO3 - -N concentration, when NO2 in the effluent of the aerobic zone - -N accumulation, NH4 + When the NO-N conversion rate is greater than 80% and the NO2--N accumulation rate is greater than 70% and remains stable for more than a week, the next start-up stage can begin. During the final stage, with the HRT set to 6 hours, observe the nitrogen removal in the anaerobic ammonia oxidation section. When the NO2--N in the effluent from the anaerobic ammonia oxidation section... - The system will start successfully if the -N concentration is less than 10 mg / L and maintained for more than one week.

[0078] (2) System operation

[0079] NH4 + Raw water with a nitrogen concentration of 1100~1300 mg / L is mixed with the returned nitrification liquid in the influent tank, so that the wastewater NH4 in the influent tank... + -N concentration is 400~600 mg / L, NO2 - The -N concentration is 100~200mg / L, and 0.2~0.7g / L of NaHCO3 is added as an inorganic carbon source. The pH is adjusted to 6.3~7.5 with H2SO4 and NaOH. Then, it is fed into the AOA reactor together with the anammox return sludge.

[0080] In the anaerobic zone, anaerobic ammonium oxidation mainly occurs, producing NH4+. + -N reacts with NO2 under hypoxic or anaerobic conditions. - -N is removed simultaneously. During the process, a mixer is used to mix the sludge and water, and a three-phase separator keeps the anaerobic ammonia oxidation sludge in the anaerobic zone. At the same time, a sludge return pump circulates the sludge, leaving only NH4 in the effluent. + -N concentration 200~300 mg / L;

[0081] Into the aerobic zone, using air pump and flow meter to control the aeration quantity, through AOB to oxidize NH4 + -N to NO2 - -N and NO3 - -N;

[0082] The effluent enters the first sedimentation zone, and the nitrification liquid reflux and nitrification sludge reflux are carried out in the first sedimentation zone, and the nitrification liquid reflux ratio is 1-2;

[0083] The remaining nitrification liquid enters the anoxic zone, and the main denitrification reaction occurs to remove the total concentration of 200-300 mg / L of NO2 - -N and NO3 - -N, and the carbon source is added through the COD adding device, and the adding amount is 400-600 mg / L, and the sludge reflux in the anoxic zone is carried out at the same time;

[0084] The final effluent is discharged from the second sedimentation zone, and the NH4 + -N concentration is less than 8 mg / L, and the total nitrogen concentration is less than 20 mg / L.

[0085] The experimental results of the embodiment show that after stable operation, in the final effluent of the process section, the COD concentration is 400-450 mg / L, the NH4 + -N concentration is less than 8 mg / L, the NO2 - -N concentration is less than 5 mg / L, the NO3 - -N concentration is less than 1 mg / L, and the total nitrogen concentration is less than 20 mg / L, and the remaining COD is difficult biodegradable organic matter, which needs subsequent physical and chemical means to remove, and the wastewater denitrification target is completed, and the effluent meets GB16889-2008.

[0086] Comparative example

[0087] The comparative example discloses a conventional nitrification-denitrification denitrification method treatment example, taking a landfill leachate membrane concentration liquid treatment plant process as an example.

[0088] The biochemical section of the plant is an A / O process, and the wastewater enters the A / O biochemical tank after the adjusting tank, the nitrification liquid reflux of the O tank is a traditional nitrification-denitrification denitrification method.

[0089] The process is provided with an A tank and an O tank, the wastewater enters the A tank from the adjusting tank, and the nitrification liquid of the O tank is refluxed to the A tank, the reflux ratio is 20-30, and the carbon source with a C / N ratio of 2-3:1 is added in the A tank to make the denitrification bacteria remove the nitrogen in the water through the denitrification effect; the wastewater flows into the O tank for aeration, and the dissolved oxygen is controlled at 2-4 mg / L, so that the nitrification bacteria oxidize NH4 + -N to NO3 - -N, to achieve ammonia nitrogen removal.

[0090] The comparative example needs to add carbon source with total nitrogen C / N of raw water of 2-3:1 when treating landfill leachate membrane concentrate of the same concentration as in Example 1, and also needs a high reflux ratio and a large amount of aeration in the O tank, and the dissolved oxygen needs to be maintained at 2-4 mg / L, and the total nitrogen in the effluent can reach the standard.

[0091] Compared with the process, 50-70% of carbon source and 40-60% of aeration amount are saved.

[0092] The above is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the scope of the present application.

Claims

1. A method for treating nitrogen-containing wastewater, characterized in that, The AOA denitrification device includes an inlet tank (1) and a continuous flow AOA reactor (2); the continuous flow AOA reactor (2) includes an anaerobic zone (21), an aerobic zone (22), a first sedimentation zone (23), an anoxic zone (24), and a second sedimentation zone (25) connected in sequence; the inlet tank (1) is connected to the anaerobic zone (21) of the continuous flow AOA reactor (2); The anaerobic zone (21) is equipped with a first mixer (31) and a three-phase separator (212); the aerobic zone (22) is equipped with an aeration assembly; the anoxic zone (24) is equipped with a second mixer (32) and a carbon source dosing device; the anaerobic zone (21) is equipped with a first reflux pipe, the first sedimentation zone (23) is equipped with a second reflux pipe between the aerobic zone (22), the anoxic zone (24) is equipped with a third reflux pipe, the second sedimentation zone (25) is equipped with a fourth reflux pipe between the anoxic zone (24), the first sedimentation zone (23) is equipped with a fifth reflux pipe between the first sedimentation zone (23) and the inlet tank (1); the fourth reflux pipe is connected to the carbon source dosing device via a tee. The anaerobic zone (21) includes a first anaerobic chamber and a second anaerobic chamber that are sequentially connected to the inlet tank (1). The first mixer (31) is located in the first anaerobic chamber, and the three-phase separator (212) is located in the second anaerobic chamber. A first reflux pipe is provided between the second anaerobic chamber and the first anaerobic chamber. The aerobic zone (22) includes a first aerobic chamber and a second aerobic chamber that are sequentially connected to the anaerobic zone (21), and the first aerobic chamber and the second aerobic chamber are respectively equipped with aeration components; A second reflux pipe is provided between the first sedimentation zone (23) and the aerobic zone (22); The anoxic zone (24) includes a first anoxic chamber and a second anoxic chamber that are sequentially connected to the first precipitation zone (23). The carbon source dosing device is installed in the first anoxic chamber, and a third reflux pipe is installed between the second anoxic chamber and the first anoxic chamber. The aeration assembly includes an aeration disc (221), a flow meter (222), and an aeration pump (223). The carbon source dosing device includes a carbon source water tank (241) and a carbon source dosing pump (242). The second return pipe connects to the first aerobic chamber of the aerobic zone (22); The third return pipe connects to the second hypoxic chamber of the hypoxic zone (24); The processing method includes the following steps: (1) System startup Anaerobic ammonia oxidation bacteria were mixed with sludge from the anaerobic zone of landfill leachate biochemical treatment and added to the anaerobic zone (21). Add the sludge from the aerobic zone of the landfill leachate biochemical treatment section to the aerobic zone (22). Add the sludge from the anaerobic zone of the landfill leachate biochemical treatment to the anoxic zone (24). The sludge concentration in the anaerobic zone (21), aerobic zone (22), and anoxic zone (24) was set at 4000~6000 mg / L; Raw water NH4 + The -N concentration is 800~1400mg / L, and the total nitrogen concentration is 1000~1500mg / L. The raw water is mixed with the reflux nitrification liquid in the first sedimentation zone (23) to reduce the NH4 concentration in the raw water in the inlet tank (1). + -N concentration is 350~700mg / L, inorganic carbon source is added, pH is adjusted to 6.3~7.5 with acid or alkali, and then raw water and return sludge from anaerobic zone (21) enter AOA reactor (2); In the anaerobic zone (21), an anaerobic ammonia oxidation reaction occurs. The mud and water are mixed by the first mixer (31), and the three-phase separator (212) keeps the anaerobic ammonia oxidation sludge in the anaerobic zone (21). In the aerobic zone (22), short-range nitrification occurs. The dissolved oxygen concentration in the aerobic zone (22) is maintained at 0.5~2 mg / L, which inhibits nitrite oxidizing bacteria and makes ammonia oxidizing bacteria the dominant species among nitrifying bacteria. The effluent from the aerobic zone (22) flows into the first sedimentation zone (23), and part of the supernatant from the first sedimentation zone (23) is returned to the inlet tank (1). The sludge from the first sedimentation zone (23) is returned to the aerobic zone (22). The remaining supernatant flows into the anoxic zone (24). In the anoxic zone (24), the carbon source dosage is 100~200mg / L, and the mixture is stirred. The effluent from the anoxic zone (24) flows into the second sedimentation zone (25), the sludge from the second sedimentation zone (25) is returned to the anoxic zone (24), and the effluent from the second sedimentation zone (25) is discharged. The system startup involves multiple stages, with each stage progressively reducing the hydraulic residence time until each stage meets the following requirements: Detect NH4 in each partition + -N, NO2 - -N, NO3 - -N concentration, when NO2 in the effluent of the aerobic zone (22) - -N accumulation, NH4 + -N conversion rate greater than 80%, NO2 - If the -N accumulation rate is greater than 70% and remains stable for more than a week, the next startup phase can begin. When the operation reaches the final stage, when NO2 in the effluent from the anaerobic zone (21) - The system will start successfully if the -N concentration is less than 10 mg / L and maintained for more than one week. 2) System operation NH4 + Raw water with a nitrogen concentration of 800~1400 mg / L is mixed with the reflux nitrification liquid in the first sedimentation zone (23) in the inlet tank (1), so that the wastewater NH4 in the inlet tank (1) is mixed. + -N concentration is 400~600 mg / L, NO2 - The -N concentration is 100~200mg / L, and an inorganic carbon source is added. The pH is adjusted to 6.3~7.5 with acid or alkali. The sludge is then fed into the AOA reactor (2) along with the anaerobic ammonia oxidation return sludge from the anaerobic zone (21). In the anaerobic zone (21), an anaerobic ammonia oxidation reaction occurs. The mud and water are mixed by the first mixer (31), and the three-phase separator (212) keeps the anaerobic ammonia oxidation sludge in the anaerobic zone (21). In the aerobic zone (22), the aeration rate is controlled, and NH4 in the water is removed by AOB. + -N is completely oxidized to NO2. - -N and NO3 - -N; The effluent from the aerobic zone (22) enters the first sedimentation zone (23), where nitrification liquid recirculation and nitrification sludge recirculation are carried out. The nitrification liquid recirculation ratio is 1~2. The remaining nitrification liquid enters the anoxic zone (24) for carbon source addition, and at the same time, the sludge in the anoxic zone (24) is returned. The final effluent is discharged from the second sedimentation zone (25).

2. The processing method as described in claim 1, characterized in that, Step (1) During system startup: Add 0.5~1g / L of NaHCO3 as an inorganic carbon source; adjust the pH to 6.3~7.5 with H2SO4 or NaOH; The dissolved oxygen concentration in the aerobic zone (22) was maintained at 0.5~2 mg / L; Part of the supernatant in the first sedimentation zone (23) is returned to the inlet tank (1), and the return ratio is controlled at 1~2. The amount of carbon source added in the hypoxic zone (24) is 100~200 mg / L.

3. The processing method as described in claim 1, characterized in that, Step (1) During system startup: When operating to the last stage, set the hydraulic retention time to 6 hours, and monitor the nitrogen removal in the anaerobic ammonia oxidation section of the anaerobic zone (21). When NO2 in the effluent of the anaerobic zone (21) - The system will start successfully if the -N concentration is less than 10 mg / L and maintained for more than one week.

4. The processing method as described in claim 1, characterized in that, During the operation of the system in step (2): Add 0.2~0.7 g / L of NaHCO3 as an inorganic carbon source; adjust the pH to 6.3~7.5 with H2SO4 or NaOH; Anaerobic ammonium oxidation occurred in the anaerobic zone (21) to remove NH4 at a ratio of 1:1.

32. + -N and NO2 - -N; The reflux ratio of nitrified liquid in the first sedimentation zone (23) is 1~2; In the anoxic zone (24), the carbon source dosage was 400~600 mg / L.

5. The processing method as described in claim 1, characterized in that, Step (1) During the system startup process: the hydraulic residence time is 6~48h.

6. The processing method as described in claim 5, characterized in that, The system startup process consists of three stages, with hydraulic residence times of 12h, 8h, and 6h respectively.

7. The processing method as described in claim 1, characterized in that, Finally, NH4 was released into the water. + -N concentration less than 8 mg / L, total nitrogen concentration less than 20 mg / L.

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