Micro-aerobic anammox high-efficiency biological nitrogen removal system and working method thereof

Abstract

The application discloses a kind of micro-aerobic ammonia oxidation high-efficiency biological nitrogen removal systems and working method thereof, belong to wastewater treatment technical field.Reactor is equipped with water distributor, gas lift refluxer, aeration device, effluent weir tank and on-line detection system;The top of main reaction zone is equipped with water inlet, and the bottom is equipped with main reaction zone vent;Effluent weir tank is equipped at the top of sludge-water separation zone, and effluent weir tank is communicated with outside through drain, and the bottom of sludge concentration zone is equipped with sedimentation zone vent;Aeration device is arranged in main reaction zone;The inlet of water distributor is arranged at the bottom of main reaction zone, and the outlet is arranged in sludge-water separation zone;The inlet of gas lift refluxer is arranged at the bottom of sludge concentration zone, and the outlet is arranged at the top of main reaction zone;On-line detection system is used to detect the operating parameter in reactor.The application has the advantages of less carbon source and neutralizing agent, low energy consumption, low sludge production, low operating cost, short reaction time, simplified reactor structure and reduced floor area.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of sewage treatment, and particularly relates to a micro-aerobic ammonia oxidation high-efficiency biological denitrification system and a working method thereof. BACKGROUND

[0002] Ammonia oxidation refers to a process of oxidizing ammonia nitrogen in wastewater into nitrite nitrogen and nitrate nitrogen under the action of microorganisms (nitrifying bacteria), so as to achieve the purpose of removing (or reducing) ammonia nitrogen. Biological denitrification refers to a process of converting the product of ammonia oxidation, i.e. nitrate nitrogen or nitrite nitrogen, into nitrogen gas and releasing it into the air under the action of microorganisms (denitrifying bacteria), so as to achieve the purpose of denitrification. There are many biological denitrification processes, but the mechanisms are basically the same. Both need to go through two stages of nitrification and denitrification.

[0003] The nitrification reaction is a process of oxidizing ammonia nitrogen in wastewater into nitrite or nitrate under the action of aerobic nitrifying bacteria under aerobic conditions, which includes two basic reaction steps: a reaction of converting ammonia nitrogen into nitrite by nitrite bacteria, and a reaction of converting nitrite into nitrate by nitrate bacteria. Both nitrite bacteria and nitrate bacteria are chemoautotrophic bacteria, which utilize carbon sources in wastewater to obtain energy through oxidation-reduction reaction with NH3-N. The suitable pH value of nitrifying bacteria is 8.0-8.4, and the optimal temperature is 35℃. Temperature has a great influence on nitrifying bacteria, and when the temperature drops by 10℃, the nitrification speed is halved. The DO concentration is 2-3 mg / L, the BOD5 load is 0.06-0.1 kgBOD5 / (kgMLSS·d), and the sludge age is more than 3-5 days.

[0004] The denitrification reaction is a process of reducing nitrite and nitrate into nitrogen gas and escaping from wastewater under the action of denitrifying bacteria under anoxic conditions. The process of reducing nitrate or nitrite produced in the nitrification process into N2 due to the action of facultative denitrifying bacteria is called denitrification. The electron donor in the denitrification process is various organic substrates (carbon sources). The suitable pH value of denitrifying bacteria is 6.5-8.0, the optimal temperature is 30℃, the denitrification speed significantly decreases when the temperature is lower than 10℃, and the denitrification action stops when the temperature is as low as 3℃. The DO concentration is less than 0.5 mg / L, and the BOD5 / TN is 3-5.

[0005] The biological denitrification method can remove various nitrogen-containing compounds, and the total nitrogen removal rate can reach 70%-95%, has little secondary pollution, and is relatively economical, so it is most commonly used at home and abroad. However, this denitrification method has great disadvantages, i.e. high energy consumption, large occupied area, consumption of a large amount of carbon sources and alkalinity, low efficiency at low temperature, and unstable denitrification effect. SUMMARY

[0006] In order to solve the defects of the prior art, the present application aims to provide a micro-aerobic ammonia oxidation high-efficiency biological nitrogen removal system and a working method thereof, which has low carbon source and neutralizing agent consumption, low energy consumption, low sludge production, low operation cost, short reaction time, simplified reactor structure and reduced land occupation.

[0007] The present application is realized by the following technical solutions:

[0008] The present application discloses a micro-aerobic ammonia oxidation high-efficiency biological nitrogen removal system, which comprises a reactor, the reactor is divided into two parts, one part is a main reaction zone, and the other part is sequentially provided with a sludge-water separation zone and a sludge concentration zone from top to bottom; the reactor is provided with a water distributor, a gas stripping reflux device, an aeration device, a water outlet weir tank and an online detection system; the top of the main reaction zone is provided with a water inlet, and the bottom is provided with a main reaction zone vent; the water outlet weir tank is arranged at the top of the sludge-water separation zone, the water outlet weir tank is communicated with the outside through a drain port, and the bottom of the sludge concentration zone is provided with a sedimentation zone vent; the aeration device is arranged in the main reaction zone; the inlet of the water distributor is arranged at the bottom of the main reaction zone, and the outlet is arranged in the sludge-water separation zone; the inlet of the gas stripping reflux device is arranged at the bottom of the sludge concentration zone, and the outlet is arranged at the top of the main reaction zone; and the online detection system is used for detecting the operation parameters in the reactor.

[0009] Preferably, the water distributor comprises a water distributor water inlet pipe, a water distributor main pipe and a water distributor water outlet pipe; the two ends of the water distributor main pipe are connected with the water distributor water inlet pipe and the water distributor water outlet pipe respectively, the water distributor water inlet pipe is arranged at the bottom of the main reaction zone, and the water distributor water outlet pipe is arranged in the sludge-water separation zone; a plurality of water distributor water inlets are arranged on the water distributor water inlet pipe, and a plurality of water distributor water outlets are arranged on the water distributor water outlet pipe.

[0010] Further preferably, the plurality of water distributor water inlets are distributed on the two sides of the water distributor water inlet pipe along the horizontal direction, and the plurality of water distributor water outlets are distributed on the two sides of the water distributor water outlet pipe along the horizontal direction.

[0011] Further preferably, the water distributor water inlets on the two sides of the water distributor water inlet pipe are arranged alternately, and the water distributor water outlets on the two sides of the water distributor water outlet pipe are arranged alternately.

[0012] Preferably, the gas stripping reflux device comprises a gas stripping reflux air inlet pipe, a reflux device main pipe, a feeding pipe and an air release device; the inlet of the reflux device main pipe is connected with the feeding pipe, and the gas stripping reflux outlet is arranged at the top of the main reaction zone; the feeding pipe is arranged at the bottom of the sludge concentration zone, a plurality of feeding ports are arranged on the feeding pipe; and the air release device is arranged on the reflux device main pipe and connected with the gas stripping reflux air inlet pipe.

[0013] Further preferably, a feeding valve is arranged on the feeding pipe, an air inlet valve is arranged on the gas stripping reflux air inlet pipe, and a vacuum regulating valve is arranged at the top end of the reflux device main pipe.

[0014] Further preferably, the reflux main pipe is fixedly connected with the inner wall of the reactor through a mounting support.

[0015] Preferably, the online detection system comprises a T / pH online sensor, a DO online sensor, an online ammonia nitrogen instrument, an online nitrate nitrogen instrument, an online MLSS instrument and an influent online flow instrument; the T / pH online sensor is arranged in the main reaction zone, the DO online sensor, the online ammonia nitrogen instrument, the online nitrate nitrogen instrument and the online MLSS instrument are arranged in the sludge-water separation zone, and the influent online flow instrument is arranged at the influent port.

[0016] The working method of the above-mentioned micro-aerobic ammonia oxidation high-efficiency biological denitrification system comprises:

[0017] The wastewater enters the main reaction zone in the reactor from the influent port, is mixed with the reflux sludge and then runs downward, the aeration device continuously supplies oxygen to the mixed liquid, the ammonia nitrogen in the wastewater is first subjected to nitrosation reaction to generate NO2 - , and then the micro-aerobic ammonia oxidation bacteria group uses NH4 + - as an electron donor to reduce NO2 - - to generate N2 gas and release; the mixed liquid enters from the inlet of the water distributor at the bottom of the reactor and is uniformly distributed to the middle of the sludge-water separation zone from the outlet of the water distributor; part of the mixed liquid is concentrated and refluxed in the sludge concentration zone, and part of the mixed liquid enters the sludge-water separation zone and is separated, the sludge runs downward by gravity and is combined with the sludge in the sludge concentration zone and is refluxed to the upper part of the main reaction zone by the air-lift refluxer to fully mix and react with the influent; the supernatant enters the effluent weir tank and is discharged from the drainage port to enter the next process section; the online detection system detects the operation parameters in the reactor.

[0018] Preferably, the continuous oxygen supply amount of the aeration device is 0.2-0.8 mg / L.

[0019] Compared with the prior art, the present application has the following beneficial technical effects:

[0020] The micro-aerobic ammonia oxidation high-efficiency biological denitrification system disclosed by the present application sets the main reaction zone, the sludge-water separation zone and the sludge concentration zone in the reactor, and realizes the synchronous completion of ammonia oxidation and denitrification in the micro-aerobic ammonia oxidation process through the setting of the water distributor, the air-lift refluxer, the aeration device and the effluent weir tank. The reactor has compact structure, fast reaction speed and short distance, and multiple reaction steps can be completed in one reactor, so that the reaction time can be greatly shortened, and therefore the residence time can also be greatly shortened, saving 50%-75% compared with the traditional process. Therefore, the structure of the reactor can be greatly simplified, and the land occupation can be reduced.

[0021] Further, the water distributor inlet on both sides of the water distributor inlet pipe is staggered, which can improve the uniformity of water inlet; the water distributor outlet on both sides of the water distributor outlet pipe is staggered, which can improve the uniformity of water outlet.

[0022] Further, the water distributor inlet on both sides of the water distributor inlet pipe is staggered, which can improve the uniformity of water inlet; the water distributor outlet on both sides of the water distributor outlet pipe is staggered, which can improve the uniformity of water outlet.

[0023] Further, the feed pipe is provided with a feed valve, and the gas stripping backflow air inlet pipe is provided with an air inlet valve, which can adjust the feed speed and air inlet speed in real time; the top end of the backflow device main pipe is provided with a vacuum regulating valve, which can adjust the negative pressure parameter.

[0024] Further, the backflow device main pipe is fixedly connected with the inner wall of the reactor through the mounting bracket, which can reduce the vibration generated by the gas-liquid-solid mixing of the backflow device.

[0025] Further, various online sensors are arranged at key positions in the reactor, which can comprehensively monitor the parameters in the reactor and realize automatic control.

[0026] Anaerobic ammonia oxidation technology is a new process of efficient denitrification technology in recent years, but the probability of ammonia oxidation in strict anaerobic environment is very low, because there is almost no excess oxygen in the anaerobic environment to continuously nitrate or nitrify ammonia nitrogen, only when the appropriate and continuous oxygen is first oxidized to nitrite by the nitrosation bacteria group, the denitrification reaction can occur.

[0027] The working method of the above-mentioned micro-oxygen ammonia oxidation high-efficiency biological denitrification system disclosed by the application is that in the environment of trace oxygen, the nitrosation bacteria first oxidize part of the ammonia nitrogen to nitrite (NO2) by using trace oxygen, and the other part of the ammonia nitrogen reacts with the nitrite to generate nitrogen and release under the action of the ammonia oxidation bacteria, thereby completing the denitrification reaction process; meanwhile, another reaction product, nitric oxide (NO), in the ammonia nitrogen nitrosation process can also react with the ammonia nitrogen to generate nitrogen (N2) and release under the action of the nitrosation bacteria, thereby realizing the denitrification reaction; the two reactions can occur simultaneously and synchronously; the ammonia nitrogen continuously enters the reactor with the water, and appropriate oxygen is continuously provided to maintain the reaction uninterrupted; according to the amount of the continuous water ammonia nitrogen, a certain amount of oxygen is continuously provided to maintain the continuous and stable operation. + In the micro-oxygen ammonia oxidation process of the application, the ammonia can be directly used as the electron donor of the denitrification reaction, so that additional carbon source is not needed, which not only saves the cost, but also prevents secondary pollution; oxygen can be economically and effectively utilized, and the oxygen supply energy consumption is greatly reduced. This is because in the nitration reaction, 2mol O2 is consumed for every 1mol NH4 + N2O5.+ Only 0.75 mol O2 is required, resulting in a 62.5% reduction in oxygen consumption. Because ammonia oxidation and denitrification occur simultaneously during micro-oxygen ammonia oxidation, acid production is significantly reduced, while alkali production drops to zero, thus saving the cost of additional acid-base neutralization reagents. This is because 1 mol NH4... + Only 1 mol of H is produced + The nitration reaction produces 2 mol H₂. + In the denitrification reaction, for every 1 mol of NO3 reduced... - or NO2 - Both will produce 1 mol OH - No alkali is produced during the micro-ammonia oxidation process; compared with the traditional nitrification system, the sludge production of the micro-ammonia oxidation process is extremely low, about 30% of the traditional one, so its operating cost is much lower. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall system structure of the present invention.

[0029] In the diagram: 1 is the reactor, 2 is the inlet, 3 is the main reaction zone, 4 is the sludge thickening zone, 5 is the sludge-water separation zone, 6 is the water distributor, 7 is the water distributor outlet pipe, 8 is the air lift reflux inlet, 9 is the air lift reflux device, 10 is the air lift reflux air inlet pipe, 11 is the air lift reflux outlet, 12 is the aeration device, 13 is the effluent weir, 14 is the drain outlet, 15 is the vent in the main reaction zone, 16 is the vent in the settling zone, 17 is the T / pH online sensor, 18 is the DO online sensor, 19 is the online ammonia nitrogen meter, 20 is the online nitrate nitrogen meter, 21 is the online MLSS meter, and 22 is the online influent flow meter. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. This description is intended to explain the invention and not to limit it.

[0031] like Figure 1The micro-aerobic ANAMMOX high-efficiency biological nitrogen removal system comprises a reactor 1, which is divided into two parts, one part is a main reaction zone 3, and the other part is sequentially provided with a sludge-water separation zone 5 and a sludge concentration zone 4 from top to bottom; the reactor 1 is provided with a water distributor 6, a gas stripping reflux device 9, an aeration device 12, a water outlet weir tank 13 and an online detection system; the top of the main reaction zone 3 is provided with a water inlet 2, and the bottom is provided with a main reaction zone vent 15; the water outlet weir tank 13 is arranged at the top of the sludge-water separation zone 5, and the water outlet weir tank 13 is communicated with the outside through a drain 14; the bottom of the sludge concentration zone 4 is provided with a settling zone vent 16; the aeration device 12 is arranged in the main reaction zone 3; the inlet of the water distributor 6 is arranged at the bottom of the main reaction zone 3, and the outlet is arranged in the sludge-water separation zone 5; the inlet of the gas stripping reflux device 9 is arranged at the bottom of the sludge concentration zone 4, and the outlet is arranged at the top of the main reaction zone 3; and the online detection system is used for detecting the operation parameters in the reactor 1.

[0032] In a preferred embodiment of the present application, the water distributor 6 comprises a water distributor inlet pipe, a water distributor main pipe and a water distributor outlet pipe 7; the two ends of the water distributor main pipe are connected with the water distributor inlet pipe and the water distributor outlet pipe 7 respectively, the water distributor inlet pipe is arranged at the bottom of the main reaction zone 3, and the water distributor outlet pipe 7 is arranged in the sludge-water separation zone 5; a plurality of water distributor inlets are arranged on the water distributor inlet pipe, and a plurality of water distributor outlets are arranged on the water distributor outlet pipe 7. Preferably, the plurality of water distributor inlets are distributed on the two sides of the water distributor inlet pipe along the horizontal direction, and the plurality of water distributor outlets are distributed on the two sides of the water distributor outlet pipe 7 along the horizontal direction. Preferably, the water distributor inlets on the two sides of the water distributor inlet pipe are arranged alternately, and the water distributor outlets on the two sides of the water distributor outlet pipe 7 are arranged alternately.

[0033] In a preferred embodiment of the present application, the gas stripping reflux device 9 comprises a gas stripping reflux inlet pipe 10, a reflux device main pipe, a feed pipe and an air release device, the inlet of the reflux device main pipe is connected with the feed pipe, and a gas stripping reflux outlet 11 is arranged at the top of the main reaction zone 3; the feed pipe is arranged at the bottom of the sludge concentration zone 4, a plurality of feed inlets are arranged on the feed pipe; and the air release device is arranged on the reflux device main pipe and connected with the gas stripping reflux inlet pipe 10. Preferably, a feed valve is arranged on the feed pipe, an air inlet valve is arranged on the gas stripping reflux inlet pipe 10, and a vacuum regulating valve is arranged at the top end of the reflux device main pipe. Preferably, the reflux device main pipe is fixedly connected with the inner wall of the reactor 1 through a mounting bracket.

[0034] In a preferred embodiment of the present application, the on-line detection system comprises a T / pH on-line sensor 17, a DO on-line sensor 18, an on-line ammonia nitrogen instrument 19, an on-line nitrate nitrogen instrument 20, an on-line MLSS instrument 21 and an on-line influent flow instrument 22; the T / pH on-line sensor 17 is arranged in the main reaction zone 23, the DO on-line sensor 18, the on-line ammonia nitrogen instrument 19, the on-line nitrate nitrogen instrument 20 and the on-line MLSS instrument 21 are arranged in the sludge-water separation zone 26, and the on-line influent flow instrument 22 is arranged at the influent port 2.

[0035] The micro-aerobic ammonia oxidation high-efficiency biological denitrification system of the present application works as follows:

[0036] The wastewater enters the main reaction zone 3 in the reactor 1 from the influent port 2, is mixed with the return sludge and then runs downward, the aeration device 12 continuously supplies oxygen to the mixed liquid, so that the ammonia nitrogen in the wastewater is first subjected to a nitrosation reaction to generate NO2 - , and then the micro-aerobic ammonia oxidation bacteria group uses NH4 + as an electron donor to reduce NO2 - to generate N2 gas and release; the mixed liquid enters from the inlet of the water distributor 6 at the bottom of the reactor 1 and is uniformly distributed to the middle of the sludge-water separation zone 5 from the outlet of the water distributor 6; part of the mixed liquid is concentrated and returned in the sludge concentration zone 4, and part of the mixed liquid is separated after entering the sludge-water separation zone 5, the sludge runs downward by gravity and merges with the sludge in the sludge concentration zone 4 and is returned to the upper part of the main reaction zone 3 by the air-lift return device 9 to fully mix and react with the influent; the supernatant enters the effluent weir tank 13 and is discharged from the drainage port 14 to the next process section; the on-line detection system detects the operating parameters in the reactor 1.

[0037] In a preferred embodiment of the present application, the continuous oxygen supply amount of the aeration device 12 is 0.2-0.8 mg / L.

[0038] The principles and equations of the conventional denitrification reaction and the short-range simultaneous micro-aerobic ammonia oxidation reaction are described in detail as follows:

[0039] Principle of conventional biological denitrification:

[0040] The conventional biological denitrification of wastewater is completed in two stages. This approach can also be referred to as full-range (or complete) nitrification-denitrification biological denitrification.

[0041] The first stage is the nitrification stage, in which the ammonia is converted into nitrate by bacteria such as nitrite bacteria and nitrifying bacteria under aerobic conditions, and the reaction can be represented by equations (1) and (2):

[0042] NH4 + + 1.5O2→ NO2 - + H2O + 2H + (1) (2)

[0043] 2NO2 - +O2→2NO3 - (nitrification process, aerobic) (2)

[0044] Overall reaction: NH4 + +2O2→NO3 - +H2O+2H + (3)

[0045] These microorganisms undergo a series of single-electron reactions in the presence of mediators, the pathway of which is roughly as follows [1]:

[0046] NH4 + →(NH2)→NH2OH→(NHOH)→(NOH)→NO→NO2 - →NO3 - (4)

[0047] The second stage is the denitrification stage, in which heterotrophic facultative bacteria participate in reduction reactions under anaerobic (or anoxic) conditions. In this process, nitrate acts as an electron acceptor and organic carbon as a carbon source and energy source. The denitrification pathway is as follows:

[0048] NO3 - → NO2 - → NO → N2 (5)

[0049] Therefore, a complete denitrification process, in which ammonia nitrogen in water is converted into nitrogen gas, involves the following steps:

[0050] NH4 + → NO2 - → NO3 - → NO2 - → N2 (6)

[0051] The above process is the theoretical basis for traditional denitrification technology.

[0052] Denitrification mechanism of micro-aerobic ammonia oxidation:

[0053] Micro-aerobic ammonia oxidation refers to the biological oxidation process in which a portion of NH4 + -N is directly oxidized by ammonia-oxidizing microbial flora after nitrosation, and another portion of NH4 + -N is used as an electron donor to oxidize NO2 - -N as an electron acceptor, converting NH4 + -N, NO2 - -N into N2 under micro-aerobic or anoxic conditions [2]. In this process, the oxidation of NH4 + -N does not require the participation of molecular oxygen, while NO2 -The reduction of -N also does not need to involve organic substances.

[0054] At present, a large number of researchers are engaged in long-term and persistent research on "anaerobic ammonia oxidation", and it is speculated that there can be multiple reaction pathways of "anaerobic ammonia oxidation".

[0055] One: NH4 + -N is oxidized to hydroxylamine NH2OH, NH2OH and NO2 - -N generates N2O, and N2O is further converted into N2;

[0056] Two: NH4 + -N and NH2OH react to generate N2H4, N2H4 is converted into N2, and four reducing [H] are generated, which are transmitted to the nitrite reduction system to form NH2OH;

[0057] Three: NO2 - -N is reduced to nitric oxide (NO), NO is reduced to N2O, and N2O is further reduced to N2 or NH4 + oxidized to NH2OH, and NH2OH is converted to N2 through N2H4.

[0058] The above is only part of the embodiments of the present application, and although some terms are used in the present application, the possibility of using other terms is not excluded. The use of these terms is only for the convenience of describing and explaining the essence of the present application, and any interpretation of them as additional limitations is contrary to the spirit of the present application. The above is only used as an example to further illustrate the content of the present application, so as to be easier to understand, but it does not represent that the embodiments of the present application are limited to this, any technical extension or re-creation made according to the present application is protected by the present application.

Claims

1. A micro-aerobic ANAMMOX high-efficiency biological nitrogen removal system, characterized in that, The reactor (1) is divided into two parts, one part is the main reaction zone (3), and the other part is sequentially provided with the sludge-water separation zone (5) and the sludge concentration zone (4) from top to bottom; the reactor (1) is provided with the water distributor (6), the air stripping reflux device (9), the aeration device (12), the effluent weir tank (13) and the online detection system; the top of the main reaction zone (3) is provided with the water inlet (2), and the bottom is provided with the main reaction zone vent (15); the effluent weir tank (13) is arranged at the top of the sludge-water separation zone (5), the effluent weir tank (13) is communicated with the outside through the drain (14), and the bottom of the sludge concentration zone (4) is provided with the settling zone vent (16); the aeration device (12) is arranged in the main reaction zone (3); the inlet of the water distributor (6) is arranged at the bottom of the main reaction zone (3), and the outlet is arranged in the sludge-water separation zone (5); the inlet of the air stripping reflux device (9) is arranged at the bottom of the sludge concentration zone (4), and the outlet is arranged at the top of the main reaction zone (3); the online detection system is used for detecting the operating parameters in the reactor (1); The water distributor (6) comprises a water distributor water inlet pipe, a water distributor main pipe and a water distributor water outlet pipe (7); the two ends of the water distributor main pipe are connected with the water distributor water inlet pipe and the water distributor water outlet pipe (7) respectively, the water distributor water inlet pipe is arranged at the bottom of the main reaction zone (3), and the water distributor water outlet pipe (7) is arranged in the sludge-water separation zone (5); a plurality of water distributor water inlets are arranged on the water distributor water inlet pipe, and a plurality of water distributor water outlets are arranged on the water distributor water outlet pipe (7); The air stripping reflux device (9) comprises an air stripping reflux air inlet pipe (10), a reflux device main pipe, a feeding pipe and an air releaser, the inlet of the reflux device main pipe is connected with the feeding pipe, and the air stripping reflux water outlet (11) is arranged at the top of the main reaction zone (3); the feeding pipe is arranged at the bottom of the sludge concentration zone (4), a plurality of feeding inlets are arranged on the feeding pipe; the air releaser is arranged on the reflux device main pipe and connected with the air stripping reflux air inlet pipe (10); The online detection system comprises a T / pH online sensor (17), a DO online sensor (18), an online ammonia nitrogen instrument (19), an online nitrate nitrogen instrument (20), an online MLSS instrument (21) and an influent online flow instrument (22); the T / pH online sensor (17) is arranged in the main reaction zone (3), the DO online sensor (18), the online ammonia nitrogen instrument (19), the online nitrate nitrogen instrument (20) and the online MLSS instrument (21) are arranged in the sludge-water separation zone (5), and the influent online flow instrument (22) is arranged in the water inlet (2).

2. The micro-aerobic ANAMMOX high-rate biological nitrogen removal system according to claim 1, characterized in that, The plurality of water distributor water inlets are distributed on the two sides of the water distributor water inlet pipe along the horizontal direction, and the plurality of water distributor water outlets are distributed on the two sides of the water distributor water outlet pipe (7) along the horizontal direction.

3. The micro-aerobic ANAMMOX high-rate biological nitrogen removal system according to claim 1, characterized in that, The water distributor water inlets on the two sides of the water distributor water inlet pipe are arranged alternately, and the water distributor water outlets on the two sides of the water distributor water outlet pipe (7) are arranged alternately.

4. The micro-aerobic ANAMMOX high-rate biological nitrogen removal system according to claim 1, characterized in that, The feeding pipe is provided with a feeding valve, the air stripping reflux air inlet pipe (10) is provided with an air inlet valve, and the top end of the reflux device main pipe is provided with a vacuum adjusting valve.

5. The micro-aerobic ANAMMOX high rate biological nitrogen removal system according to claim 1, characterized in that, The reflux device main pipe is fixedly connected with the inner wall of the reactor (1) through a mounting bracket.

6. The working method of the micro-aerobic ANAMMOX high-efficiency biological nitrogen removal system according to any one of claims 1-5, characterized in that, It comprises: Wastewater enters the upper part of the main reaction zone (3) in reactor (1) through inlet (2), mixes with the returned sludge, and then flows downward. Aeration device (12) continuously oxygenates the mixture, causing the ammonia nitrogen in the wastewater to undergo nitrification to generate NO2. — N, then the micro-ammonia-oxidizing bacteria utilize NH4 + -N acts as an electron donor for NO2 - -N is reduced to generate N2 gas and released; the mixed liquid enters from the inlet of the water distributor (6) at the bottom of the reactor (1) and is evenly distributed to the middle of the sludge-water separation zone (5) from the outlet of the water distributor (6); part of the mixed liquid is concentrated and refluxed in the sludge thickening zone (4), and part of the mixed liquid is separated after entering the sludge-water separation zone (5). The sludge moves downward by gravity and merges with the sludge in the sludge thickening zone (4) and is refluxed back to the upper part of the main reaction zone (3) by the air lift return device (9) to fully mix and react with the influent; The supernatant enters the effluent weir tank (13) and is discharged from the system through the drain (14) to enter the next process section; the online detection system detects the operating parameters in the reactor (1).

7. The working method of the micro-aerobic ANAMMOX high-efficiency biological nitrogen removal system according to claim 6, characterized in that, The continuous oxygenation amount of the aeration device (12) is 0.2-0.8 mg / L.

Images