Anaerobic ammonia oxidation synchronous nitrogen and phosphorus removal treatment system

Abstract

The utility model discloses an anaerobic ammonia oxidation synchronous nitrogen and phosphorus removal treatment system which comprises an anaerobic tank, an aerobic tank, a sedimentation tank and an anaerobic ammonia oxidation tank which are connected in sequence and are common-wall tank bodies or independent tank bodies, the sedimentation tank is in water communication with the aerobic tank through a communication pipe and a central vertical flow cylinder, a sludge hopper is arranged at the bottom of the sedimentation tank, and a sludge return pipeline is connected with the anaerobic tank; a heating coil is arranged in a bottom water distribution area of the anaerobic ammonia oxidation tank, an inlet of the heating coil is connected with a hot air inlet pipe, and an outlet is connected with an aeration device arranged at the bottom of the aerobic tank through a pipeline; a water outlet channel is arranged on the annular wall of the anaerobic ammonia oxidation tank, and a stirrer is arranged in the center of the anaerobic ammonia oxidation tank; and an effluent return pipe is arranged on the side wall of the bottom of the anaerobic ammonia oxidation tank. According to the utility model, the problems of contradiction between denitrification and dephosphorization in a synchronous denitrification and dephosphorization technology, difficulty in further improvement of efficiency, difficulty in enrichment of bacteria in an anaerobic ammonia oxidation process, long starting period and the like are solved.

Description

Technical Field

[0001] This utility model belongs to the field of environmental protection technology, and in particular to the field of wastewater treatment technology, specifically relating to an anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal treatment system. Background Technology

[0002] Currently, the principles of simultaneous nitrogen and phosphorus removal processes used in urban domestic sewage are basically the same. They all combine biological nitrogen removal and biological phosphorus removal, using different microorganisms under different oxygen conditions to achieve the purpose of nitrogen and phosphorus removal.

[0003] Biological denitrification involves three steps. First, organic nitrogen is oxidized to ammonia by ammonifying bacteria under aerobic or anoxic conditions. Second, ammonia and ammonium ions are oxidized to nitrite or nitrate by nitrifying bacteria under aerobic conditions. Third, nitrite and nitrate are reduced to nitrogen gas by denitrifying bacteria under anoxic conditions. This completes the denitrification reaction. This process is complex and involves interdependent interactions. Biological phosphorus removal relies on polyphosphate-accumulating bacteria releasing phosphorus under anaerobic conditions and absorbing excess phosphorus under aerobic conditions, achieving phosphorus removal through the removal of excess sludge. The entire simultaneous denitrification and phosphorus removal process involves four types of bacteria. Nitrifying bacteria are the main bacteria affecting the effectiveness of biological denitrification; they are chemoautotrophic bacteria characterized by long generation times, low growth rates, and extreme sensitivity to the environment.

[0004] Current nitrogen and phosphorus removal processes are basically anaerobic + anoxic + aerobic + sedimentation. Activated sludge systems are widely used. To maintain sludge concentration within the system, sludge needs to be returned from the sedimentation tank to the anaerobic tank. Additionally, due to the pre-anoxic stage, mixed liquor also needs to be returned from the end of the aerobic tank to the beginning of the anoxic tank—that is, sludge return and mixed liquor return. The sludge returned from the sedimentation tank to the anaerobic tank contains four types of bacteria involved in nitrogen and phosphorus removal. Polyphosphate-accumulating bacteria (PABs) are the main species for biological phosphorus removal. Although heterotrophic, they have strict requirements for organic matter and can only absorb volatile fatty acids (VFAs) from wastewater. In the presence of other bacteria in the anaerobic tank, PPAs are at a growth disadvantage and cannot become the dominant species, inevitably affecting the efficiency of biological phosphorus removal. Furthermore, the returned sludge inevitably carries some nitrates into the anaerobic tank, severely affecting the phosphorus release efficiency of PPAs, and thus impacting phosphorus removal efficiency.

[0005] Phosphorus removal primarily relies on the discharge of excess sludge. The greater the amount of excess sludge discharged, the better the phosphorus removal effect. Phosphorus removal requires a relatively short sludge age, generally 3.5-7 days. Nitrifying bacteria have a longer generation time and require a longer sludge age, generally 10-22 days, to grow and reproduce in large quantities and become the dominant bacteria in the aerobic tank, ensuring the effectiveness of biological nitrogen removal. Therefore, the sludge age requirements for nitrifying bacteria and biological phosphorus removal are contradictory.

[0006] Biological denitrification efficiency is positively correlated with the sum of the mixed liquor and sludge return ratios; that is, the higher the sum, the better the denitrification effect. However, when the mixed liquor return ratio exceeds a certain value, the anoxic tank cannot maintain a good anoxic state, and the denitrification effect will actually decrease. Excessive sludge return can cause the anaerobic tank to lose its anaerobic state, leading to a decrease in biological phosphorus removal efficiency. Therefore, high denitrification usually comes at the cost of sacrificing some phosphorus removal efficiency, requiring the subsequent addition of chemical phosphorus removal units to compensate for the loss of phosphorus removal efficiency, thus increasing system investment and operating costs.

[0007] To achieve high nitrogen removal efficiency using traditional simultaneous nitrogen and phosphorus removal processes, in addition to auxiliary chemical phosphorus removal, a post-nitrogen removal unit is often required, along with a carbon source addition device. This process is characterized by high oxygen demand and the addition of a large amount of carbon source.

[0008] Anaerobic ammonia oxidation (ANAMMOX) technology is currently the most economical and effective biological nitrogen removal pathway known. Compared with traditional nitrification and denitrification technologies, it has advantages such as low oxygen demand, low sludge production, and no need for external carbon sources, and has broad prospects for widespread application. However, ANAMMOX bacteria grow slowly, with a generation cycle of about 11 days. They also have low cell yield, small size, are easily lost, and are extremely sensitive to environmental conditions, making it difficult to enrich ANAMMOX bacteria. In addition, the start-up time of ANAMMOX reactors is too long, which seriously restricts the development of ANAMMOX technology in the field of water treatment. Summary of the Invention

[0009] This invention discloses an anaerobic ammonia oxidation (AA) simultaneous nitrogen and phosphorus removal system to address the shortcomings of existing technologies. Specifically, it addresses the problems of contradictory nitrogen and phosphorus removal processes, difficulty in further improving efficiency, and the challenges of bacterial enrichment and long start-up cycles in existing AA processes. This invention simultaneously improves nitrogen and phosphorus removal efficiency, enhances the enrichment of anaerobic ammonia oxidizing bacteria, shortens the start-up cycle, and reduces operating costs.

[0010] This utility model is achieved through the following technical solution:

[0011] An anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system is characterized by comprising an anaerobic tank, an aerobic tank, a sedimentation tank, and an anaerobic ammonia oxidation tank, the four tanks being sequentially linked and either shared-wall tanks or independent tanks.

[0012] The anaerobic tank receives wastewater to be treated via pipeline;

[0013] The aerobic tank and the anaerobic tank are connected by a connecting hole or a connecting pipe at the bottom of the partition plate. An aeration device is installed at the bottom of the aerobic tank.

[0014] The sedimentation tank and the aerobic tank are connected by a connecting pipe and a central vertical flow tube. A funnel-shaped sludge hopper is set at the bottom of the sedimentation tank, and a sludge pump is arranged in the sludge hopper and connected to the anaerobic tank through a sludge return pipe. A sedimentation tank effluent channel is set on the upper ring wall of the sedimentation tank, and a water distribution pipe is set at the bottom of the sedimentation tank effluent channel.

[0015] The bottom of the anaerobic ammonia oxidation tank receives effluent from the sedimentation tank via a water distribution pipe. A heating coil is installed in the water distribution area at the bottom of the anaerobic ammonia oxidation tank; the inlet of the heating coil is connected to the air inlet pipe, and the outlet is connected to the aeration device installed at the bottom of the aerobic tank via a pipe. The air inlet pipe is connected to a hot air device. An intercepting screen is installed at the top of the anaerobic ammonia oxidation tank to form a fixed bed of packing material extending from the bottom to the intercepting screen, filled with suspended packing material. A effluent channel is installed on the ring wall above the intercepting screen, and an effluent pipe is installed in the effluent channel to connect with subsequent treatment processes. A stirrer is installed in the center of the anaerobic ammonia oxidation tank. An effluent return pipe is installed on the bottom side wall of the anaerobic ammonia oxidation tank.

[0016] Furthermore, the aerobic tank inlet is equipped with an online ammonia nitrogen detector; the sedimentation tank is equipped with an online nitrite, nitrate, and ammonia nitrogen detector and an alkalinity meter; and the anaerobic ammonia oxidation tank is equipped with dissolved oxygen, alkalinity, temperature, and pH meters.

[0017] Furthermore, the inlet of the connecting pipe between the sedimentation tank and the aerobic tank is located 700mm below the water level of the aerobic tank, and the outlet of the connecting pipe is connected to the wall of the central vertical flow cylinder located at the vertical center of the sedimentation tank.

[0018] Furthermore, the heating coil is a copper heating tube arranged in a U-shape.

[0019] Furthermore, the outlet of the water distribution pipe and the outlet of the effluent return pipe are located in the water distribution area of ​​the anaerobic ammonia oxidation tank; the agitator is equipped with stirring blades in at least the water distribution area to achieve uniform water distribution or backwashing.

[0020] Furthermore, the agitator is a hyperboloid agitator made of fiberglass.

[0021] Furthermore, the fixed bed of the packing consists of a packing interception screen plate, a supporting structure, and a pool body; the packing interception screen plate is a stainless steel plate with uniform openings, and the supporting structure is located below the packing interception screen plate and is made of angle steel or shaped steel; the packing interception screen plate is a detachable structure.

[0022] Furthermore, the intercepting screen plate is installed 0.5m below the effluent channel of the anaerobic ammonia oxidation tank, and the opening rate of the intercepting screen plate is 30-35% of the screen plate area.

[0023] Furthermore, the fixed bed packing has a filling rate of 60-80% by volume.

[0024] Furthermore, both the sedimentation tank effluent channel and the anaerobic ammonia oxidation tank effluent collection system are triangular weir plate effluent collection systems.

[0025] Advantages compared to other simultaneous nitrogen and phosphorus removal systems:

[0026] (1) The anaerobic ammonia-oxidizing bacteria used in this invention are chemoautotrophic bacteria that, under anaerobic conditions, utilize HCO3- to oxidize oxygen. - Since it serves as a carbon source, no additional carbon source needs to be added when treating wastewater with a low carbon-to-nitrogen ratio, thus saving operating costs.

[0027] (2) In this invention, the anaerobic ammonia oxidation tank is set at the rear end of the aerobic tank. Nitrite enters the anaerobic ammonia oxidation tank with the effluent from the aerobic tank. Therefore, no internal reflux system is required, the process flow is relatively simple, the denitrification efficiency is not affected by the internal reflux ratio and the anoxic state of the anoxic tank, and energy consumption is saved.

[0028] (3) The sedimentation tank at the front end of this utility model is only used for phosphorus removal, while the anaerobic ammonia oxidation tank at the back end is dedicated to denitrification. Separating the denitrification sludge age and the phosphorus removal sludge age can simultaneously improve the efficiency of denitrification and phosphorus removal, saving the cost of chemical phosphorus removal agents.

[0029] (4) This utility model makes full use of the characteristics of anaerobic ammonia-oxidizing bacteria having a long generation time and a lower growth rate than denitrifying bacteria. The sludge production is only 15% of that of traditional biological denitrification process, which reduces the sludge treatment and disposal costs.

[0030] (5) Compared to conventional biological nitrogen removal processes, the nitrification reaction in this invention only needs to proceed to the nitrite stage, so the residence time in the aerobic tank is relatively short. Furthermore, the nitrogen removal load of the anaerobic ammonia oxidation tank is higher than that of heterotrophic denitrification, and its volume is relatively smaller, resulting in a shorter residence time. Therefore, the overall residence time of this process is shorter than that of conventional nitrogen and phosphorus removal processes, saving land area and reducing investment.

[0031] (6) The aerobic tank nitrification reaction of this utility model only requires the oxidation of organic nitrogen and ammonia nitrogen to nitrite, which requires less oxygen than conventional denitrification processes and can save energy.

[0032] (7) The suspended packing material added to the anaerobic ammonia oxidation tank of this utility model and the packing interception device at the top of the tank form a fixed bed structure with a high filling rate, which has the effect of intercepting suspended solids. Therefore, there is no need to set up a mud-water separation device at the back end, the reaction process is short, and the land is saved.

[0033] (8) This utility model uses the effluent for backwashing, eliminating the need for a clear water tank. The backwash effluent is directly discharged into subsequent treatment equipment, without increasing the system load.

[0034] (9) This utility model utilizes the heat carried by the blower room duct to heat the copper pipe at the bottom of the anaerobic ammonia oxidation tank, thereby maintaining the temperature of the anaerobic ammonia oxidation tank. No additional heat or heat source is required, thus saving energy.

[0035] This invention combines biological phosphorus removal technology with anaerobic ammonia oxidation (AAO) nitrogen removal technology, not only resolving many contradictory issues inherent in traditional biological nitrogen and phosphorus removal processes but also simultaneously improving both. Nitrogen removal efficiency no longer depends on the mixed liquor and sludge return ratio, significantly saving energy. The biological phosphorus removal system is completely independent, unaffected by biological nitrogen removal, boasts high phosphorus removal efficiency, and eliminates the need for auxiliary chemical phosphorus removal, reducing investment and operating costs. It also solves problems such as the difficulty in bacterial enrichment and long start-up cycles associated with anaerobic ammonia oxidation processes. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system of this utility model.

[0037] In the diagram, 1 is the anaerobic tank, 2 is the aerobic tank, 3 is the sedimentation tank, 4 is the anaerobic ammonia oxidation tank, 6 is the sludge pump, 7 is the sludge return pipe, 8 is the aeration system, 9 is the sedimentation tank effluent channel, 10 is the water distribution pipe, 11 is the heating copper pipe, 12 is the water distribution area, 13 is the hyperboloid mixer, 14 is the packing area, 15 is the suspended packing, 16 is the packing interception screen plate, 18 is the support structure, 19 is the effluent collection area, 20 is the effluent channel, and 21 is the triangular weir plate. 22 is the sludge hopper, 23 is the effluent pipe, 24 is the effluent return pipe, 25 is the air inlet pipe, 26 is the sludge discharge pipe, 27 is the ammonia nitrogen detector for the aerobic tank, 28 is the nitrate detector for the sedimentation tank, 29 is the nitrite detector for the sedimentation tank, 30 is the ammonia nitrogen detector for the sedimentation tank, 31 is the alkalinity detector for the sedimentation tank, 32 is the dissolved oxygen detector, 33 is the alkalinity detector, 34 is the thermometer, 35 is the pH meter, 36 is the central vertical flow tube, and 37 is the connecting pipe. Detailed Implementation

[0038] The present invention will be further described below with reference to specific embodiments. These specific embodiments are further explanations of the principle of the present invention and are not intended to limit the present invention in any way. Any technology that is the same as or similar to the present invention does not exceed the protection scope of the present invention.

[0039] Refer to the attached diagram.

[0040] This utility model embodiment of the anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal technology includes an anaerobic tank 1, an aerobic tank 2, a sedimentation tank 3, and an anaerobic ammonia oxidation tank 4, which are connected sequentially. The anaerobic tank 1, aerobic tank 2, and sedimentation tank 3 have the functions of biological phosphorus removal, carbonization, nitrification, and sedimentation separation. They also serve as pretreatment for the anaerobic ammonia oxidation tank 4, providing nitrite and ammonium ions to the anaerobic ammonia oxidation tank 4. The anaerobic ammonia oxidation tank 4 adopts a fixed bed structure.

[0041] Anaerobic tank 1 and aerobic tank 2 adopt the activated sludge process.

[0042] A sludge return system is provided between anaerobic tank 1 and sedimentation tank 3, consisting of sludge return pump 6 and return pipe 7.

[0043] The sedimentation tank 3 has an effluent weir 9 at the top and a sludge hopper 22 at the bottom. A central vertical flow tube 36 is located in the middle and is connected to the anaerobic tank 1 by gravity flow via a connecting pipe 37. A sludge discharge pipe 26 is also installed at the bottom of the sedimentation tank 3 to discharge sludge.

[0044] The aerobic tank 2 is equipped with an aerobic tank ammonia nitrogen detector 27 at its inlet. The sedimentation tank 3 is equipped with a sedimentation tank nitrite detector 29, a sedimentation tank nitrate detector 28, a sedimentation tank ammonia nitrogen detector 30, and a sedimentation tank alkalinity meter 31. The anaerobic ammonia oxidation tank is equipped with a dissolved oxygen detector 32, an alkalinity meter 33, a thermometer 34, and a pH meter 35.

[0045] The anaerobic ammonia oxidation tank 4, from bottom to top, includes: heating copper pipe 11, water distribution zone 12, hyperboloid agitator 13, packing zone 14, packing interception device 16, and effluent collection zone 19.

[0046] Heating copper pipes 11 installed at the bottom of the anaerobic ammonia oxidation tank 4 are used for heat preservation of the anaerobic ammonia oxidation tank. The heated air from the blower room enters through the oil inlet pipe 25, passes through the heating copper pipes 11 at the bottom of the anaerobic ammonia oxidation tank 4, and then enters the aerobic tank 2 for aeration through the aeration system 8. The heating copper pipes 11 are arranged in a U-shape.

[0047] The anaerobic ammonia oxidation tank 4, water distribution zone 12 is equipped with water distribution pipe 10 and water return pipe 24. During normal operation, the influent is evenly distributed in the tank under the action of the hyperboloid agitator. During backwashing, the influent and backwashing influent are evenly backwashed under the agitation of the hyperboloid agitator.

[0048] The hyperboloid agitator 13 in the anaerobic ammonia oxidation tank is made of fiberglass. The guide rod of the hyperboloid agitator 13 passes through the packing interception screen plate 16 and connects to the impeller. During maintenance, the four movable packing interception screen plates 16 around the guide rod are removed.

[0049] The anaerobic ammonia oxidation tank 4 is filled with suspended packing material 15 to form a fixed bed structure, providing attachment points for anaerobic ammonia oxidizing bacteria. These bacteria can grow and reproduce on the surface of the suspended packing material 15, forming a stable biofilm structure, which is beneficial for their growth and enhances their accumulation. The fixed bed structure consists of suspended packing material 15 with a filling rate of 60-80% and a packing interception device. This reduces the destructive effect of hydraulic shear force on sludge aggregates and has a retention function. The suspended packing material 15 is made of HDPE with a specific surface area of ​​400-600 m². 2 / m 3 .

[0050] The fixed-bed packing device consists of a packing interception screen plate 16 and a supporting structure 18. The packing interception screen plate 16 is made of stainless steel and is composed of several stainless steel plates with uniformly sized openings. The supporting structure 18 is located below the baffle and is composed of angle steel and structural steel. The packing interception screen plate 16 is movable. The packing interception screen plate 16 is located approximately 0.5m below the outlet channel, with an opening ratio of 30-35%.

[0051] The anaerobic ammonia oxidation tank 4 has an effluent collection system consisting of an effluent channel 20 and a triangular weir plate 21 on its four sides below a certain height at the top. After collection, the effluent from the anaerobic ammonia oxidation tank 4 enters the next stage treatment structure through the effluent pipe 23.

[0052] The operation of anaerobic tank 1, aerobic tank 2, and sedimentation tank 3 requires control of the nitrification reaction process in the aerobic tank.

[0053] The water quality of aerobic tank 2 should meet the following standards: (1) pH 7.5-9.0; (2) dissolved oxygen (DO) 0.2-1.0 mg / L, which can be adjusted according to the effluent water quality requirements;

[0054] The influent water quality of the anaerobic ammonia oxidation tank 4 should meet the following standards: (1) pH 6.7-8.5; (2) alkalinity greater than 4 times that of HN4. + -N, if the requirement is not met, alkali or acid supplementation agents should be added; (3) COD / TKN is less than 3; (4) The water temperature of the anaerobic ammonia oxidation tank should be 20℃~38℃.

[0055] The backwash water for the anaerobic ammonia oxidation tank 4 is the effluent from the clear water tank. The backwashing frequency is once every two weeks, the washing time is 10-15 minutes, and the washing intensity is 10-15 L / (m²). 2 .S).

[0056] The flushing water from anaerobic ammonia oxidation tank 4 is connected to subsequent treatment equipment.

[0057] The treatment process of the anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal device of this utility model is as follows:

[0058] The first step is that the wastewater enters the anaerobic tank 1 and mixes evenly with the return sludge from the sedimentation tank 3, and the anaerobic phosphorus release process is completed under the action of phosphorus-removing bacteria.

[0059] The second step involves the wastewater from anaerobic tank 1 flowing by gravity to aerobic tank 2. The pH in the aerobic tank is controlled at 7.5–9.0 and the dissolved oxygen at 0.2–1.0 mg / L. Phosphorus-releasing bacteria are used to complete aerobic phosphorus uptake, while ammonia nitrogen, organic nitrogen, and ammonium ions are converted into nitrite ions under the action of nitrifying bacteria.

[0060] The third step involves wastewater entering the central vertical flow tube 36 through the connecting pipe 37 between the aerobic tank 2 and the sedimentation tank 3. In the sedimentation tank, sludge and water are separated, and phosphorus is removed from the system along with the discharged excess sludge. At the same time, some sludge is returned to the anaerobic tank through the sludge pump to maintain the sludge concentration in the system. Thus, biological phosphorus removal is completed.

[0061] The phosphorus removal system of this invention is relatively independent. There are no nitrifying bacteria competing with phosphorus-removing bacteria in the anaerobic tank. Therefore, polyphosphate-accumulating bacteria can become the dominant species in the anaerobic tank, which can improve the efficiency of biological phosphorus removal and eliminate the need for subsequent chemical phosphorus removal processes.

[0062] Step 4: Wastewater carrying ammonium and nitrite ions in the aerobic tank enters the anaerobic ammonia oxidation tank 4 through the water distribution pipe 10 at the lower end of the effluent channel at the top of the sedimentation tank. Under the action of the hyperboloid stirrer 13, the wastewater is mixed evenly in the tank, and the pH in the tank is controlled at 6.7-8.5, and the alkalinity is greater than 4 times that of NH4+. + -N, COD / TKN less than 3, water temperature 20℃~38℃.

[0063] Utilizing anaerobic ammonia-oxidizing bacteria in the pond under anaerobic conditions, using HCO3 - NH4 as a carbon source + and NO2 - It is converted into N2 and completes the cellular synthesis metabolism, thus completing biological denitrification.

[0064] This invention features a system that removes phosphorus first and then denitrifies. On the one hand, nitrite and ammonium ions enter the anaerobic ammonia oxidation tank with the effluent from the aerobic tank, eliminating the need for an internal recirculation system. This simplifies the process and makes the denitrification efficiency unaffected by the internal recirculation ratio or the anoxic state of the anoxic tank. On the other hand, separating the denitrification sludge age from the phosphorus removal sludge age allows for the simultaneous improvement of both denitrification and phosphorus removal efficiency.

[0065] This invention offers advantages such as short retention time, small footprint, and low investment. Firstly, the nitrification reaction only needs to proceed to the nitrite stage, thus the retention time in the aerobic tank is relatively short. Secondly, the nitrogen removal load of the anaerobic ammonia oxidation tank is higher than that of heterotrophic denitrification, resulting in a relatively small tank volume and shorter retention time. The aerobic nitrification reaction only needs to oxidize organic nitrogen and ammonia nitrogen to nitrite, requiring less oxygen compared to conventional denitrification processes. Furthermore, the anaerobic ammonia oxidation tank needs to maintain an anaerobic state, thus the entire process also boasts low energy consumption.

[0066] Anaerobic ammonia-oxidizing bacteria are chemoautotrophic bacteria that feed on HCO3-. - Since it serves as a carbon source, no additional carbon source is needed when treating wastewater with a low carbon-to-nitrogen ratio, saving operating costs. Furthermore, anaerobic ammonia-oxidizing bacteria have a long generation time and a lower growth rate than denitrifying bacteria, resulting in sludge production that is only 15% of that produced by traditional biological denitrification processes, thus reducing sludge treatment and disposal costs.

Claims

1. An anaerobic ammonia oxidation system for simultaneous nitrogen and phosphorus removal, characterized in that: It includes an anaerobic tank, an aerobic tank, a sedimentation tank, and an anaerobic ammonia oxidation tank. The four tanks are connected in sequence and can be either shared-wall tanks or independent tanks. The anaerobic tank receives wastewater to be treated via pipeline; The aerobic tank and the anaerobic tank are connected by a connecting hole or a connecting pipe at the bottom of the partition plate. An aeration device is installed at the bottom of the aerobic tank. The sedimentation tank and the aerobic tank are connected by a connecting pipe and a central vertical flow tube. A funnel-shaped sludge hopper is set at the bottom of the sedimentation tank, and a sludge pump is arranged in the sludge hopper and connected to the anaerobic tank through a sludge return pipe. A sedimentation tank effluent channel is set on the upper ring wall of the sedimentation tank, and a water distribution pipe is set at the bottom of the sedimentation tank effluent channel. The bottom of the anaerobic ammonia oxidation tank receives effluent from the sedimentation tank via a water distribution pipe. A heating coil is installed in the water distribution area at the bottom of the anaerobic ammonia oxidation tank; the inlet of the heating coil is connected to the air inlet pipe, and the outlet is connected to the aeration device installed at the bottom of the aerobic tank via a pipe. The air inlet pipe is connected to a hot air device. An intercepting screen is installed at the top of the anaerobic ammonia oxidation tank to form a fixed bed of packing material extending from the bottom to the intercepting screen, filled with suspended packing material. A effluent channel is installed on the ring wall above the intercepting screen, and an effluent pipe is installed in the effluent channel to connect with subsequent treatment processes. A stirrer is installed in the center of the anaerobic ammonia oxidation tank. An effluent return pipe is installed on the bottom side wall of the anaerobic ammonia oxidation tank.

2. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 1, characterized in that: The aerobic tank is equipped with an online ammonia nitrogen detector at the inlet; the sedimentation tank is equipped with an online nitrite, nitrate, and ammonia nitrogen detector and an alkalinity meter; the anaerobic ammonia oxidation tank is equipped with dissolved oxygen, alkalinity, temperature, and pH meters.

3. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 2, characterized in that: The inlet of the connecting pipe between the sedimentation tank and the aerobic tank is located 700mm below the water level of the aerobic tank, and the outlet of the connecting pipe is connected to the wall of the central vertical flow cylinder located at the vertical center of the sedimentation tank.

4. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 2, characterized in that: The heating coil is a copper heating tube arranged in a U-shape.

5. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 2, characterized in that: The outlet of the water distribution pipe and the outlet of the effluent return pipe are located in the water distribution area of ​​the anaerobic ammonia oxidation tank; the agitator is equipped with stirring blades in the water distribution area to achieve uniform water distribution or backwashing.

6. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 2, characterized in that: The agitator is a hyperboloid agitator made of fiberglass.

7. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 2, characterized in that: The fixed bed of packing consists of a packing interception screen plate, a supporting structure, and a pool body; the packing interception screen plate is a stainless steel plate with uniform openings, and the supporting structure is located below the packing interception screen plate and is made of angle steel or shaped steel; the packing interception screen plate is a detachable structure.

8. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 7, characterized in that: The intercepting screen is installed 0.5m below the effluent channel of the anaerobic ammonia oxidation tank, and the opening rate of the intercepting screen is 30-35% of the screen area.

9. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 7, characterized in that: The fixed bed packing has a filling rate of 60-80% by volume.

10. The anaerobic ammonia oxidation simultaneous nitrogen and phosphorus removal system according to claim 2, characterized in that: The effluent channels of the sedimentation tank and the anaerobic ammonia oxidation tank are both triangular weir plate effluent collection systems.

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