A process and system for treating high-ammonia nitrogen wastewater with low energy consumption and low carbon source addition

Abstract

The present invention discloses a low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process and system, the process includes the following steps: S1, pretreatment stage; high-concentration ammonia nitrogen wastewater is first subjected to denitrification and short-range denitrification reaction; S2, main reaction stage; wastewater undergoes short-range nitrification reaction, anaerobic ammonia oxidation reaction, short-range denitrification reaction and organic matter degradation; S3, stable effluent stage; the remaining ammonia nitrogen and nitrite nitrogen in the wastewater are oxidized into nitrate nitrogen, and polyphosphate bacteria are used to perform aerobic phosphorus absorption reaction. The process of the present invention adopts multi-stage process combination, precise control, high solid load solid-liquid separation and concentration technology, high-rate pneumatic lifting internal and external reflux circulation technology to not only integrate the advantages of traditional A2 / O, SBR, oxidation ditch and MBR, but also has the synchronous short-range nitrification and denitrification, short-range denitrification, and anaerobic ammonia oxidation functions that are difficult to achieve in these processes, and has the advantages of strong resistance to shock loads, low operating costs, and small footprint.

Description

Technical Field

[0001] The present invention relates to the technical field of high-concentration ammonia nitrogen wastewater, and specifically to a high-concentration ammonia nitrogen wastewater treatment process and system with low energy consumption and low carbon source addition, which is referred to as BM-AAO process. Background Art

[0002] In recent years, with the increasing expansion of urban population and the continuous development of industry and agriculture, water pollution accidents have occurred repeatedly, posing serious harm to humans and livestock. Many lakes and reservoirs have caused eutrophication due to the discharge of nitrogen and phosphorus, which seriously threatens human production and life and ecological balance. Ammonia nitrogen is one of the main factors causing eutrophication of water bodies. In order to meet the public's increasing requirements for environmental quality, the country has formulated increasingly stringent emission standards for nitrogen. Research and development of economical and efficient nitrogen removal treatment technology has become the focus and hotspot of research in the field of water pollution control engineering.

[0003] The existing technologies for denitrification of high-concentration ammonia nitrogen wastewater include chlorination at breaking point, air stripping, chemical precipitation, and ion exchange. Not only are the operating costs high, but they also produce toxic and harmful substances or secondary pollutants that require further treatment. Only biological nitrification and denitrification denitrification has no secondary pollution and can be directly treated to meet discharge standards.

[0004] Traditional biological nitrification and denitrification denitrification technology still has the following problems in wastewater denitrification:

[0005] (1) In order to maintain a high biomass concentration and obtain a good denitrification effect, sludge recirculation and digestion liquid recirculation must be performed simultaneously, which not only increases power consumption but also increases operating costs;

[0006] (2) The acidity generated during the nitrification process needs to be neutralized by adding a certain amount of alkali, which increases the treatment cost;

[0007] (3) C / N ≥ 4 is required for better denitrification. For wastewater with a relatively low C / N, a large amount of carbon source needs to be added, which results in huge treatment costs.

[0008] (4) The nitrification process is completed under aerobic conditions and requires a lot of energy consumption;

[0009] (5) In the presence of a large amount of organic matter, autotrophic nitrifying bacteria are not as competitive as heterotrophic aerobic bacteria for oxygen and nutrients, resulting in the dominance of heterotrophic bacteria; denitrifying bacteria use organic matter as electron donors, and the presence of organic matter will affect the rate of nitrification reaction; the requirements of dissolved oxygen (DO) concentration for microorganisms that carry out nitrification and denitrification reactions are very different. The different requirements of nitrifying bacteria and denitrifying bacteria make it difficult to carry out nitrification and denitrification processes in a unified manner in time and space;

[0010] (6) The proliferation rate of nitrifying and denitrifying bacteria is very slow and it is difficult to maintain a high biomass concentration, which will result in a long total hydraulic retention time and low organic load in the system, leading to a large land area, increased infrastructure investment and operating costs;

[0011] (7) Weak impact resistance. High concentrations of ammonia nitrogen and nitrite in the water will inhibit the growth of nitrifying bacteria. Summary of the invention

[0012] The purpose of the present invention is to provide a high-ammonia nitrogen wastewater treatment process with low energy consumption and low carbon source addition. The denitrification treatment process has low operating costs, small footprint and does not cause secondary pollution to the environment.

[0013] To achieve the above object, the present invention provides the following technical solutions:

[0014] A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process comprises the following steps:

[0015] S1, pre-processing stage:

[0016] S1-1, high concentration ammonia nitrogen wastewater first enters a first anoxic tank from a first selection tank for denitrification and short-range denitrification reaction;

[0017] S1-2, the wastewater treated in step S1-1 enters an anaerobic tank, where polyphosphate-accumulating bacteria are used to rapidly degrade and absorb organic matter in the wastewater under anaerobic conditions;

[0018] S1-3, the wastewater treated in step S1-2 enters the aerobic pool A for further degradation of organic matter, absorption of phosphorus under aerobic conditions and accumulation of nitrite nitrogen by short-range nitrification reaction;

[0019] S1-4, the wastewater treated in step S1-3 enters zone B of the first aerobic pool to inhibit the growth of nitrite oxidizing bacteria, so that the ammonia nitrogen in the water only undergoes nitrite reaction and further organic matter degradation reaction in zone B of the first aerobic pool, and accumulates nitrite nitrogen, a substrate for anaerobic ammonia oxidation required for subsequent reactions;

[0020] Note: Placing an anoxic tank in front of an anaerobic tank is beneficial to prioritize the carbon source requirements of denitrification and anaerobic phosphorus release, strengthen the system's demand for nitrogen removal and alkali production, and allow all return sludge to undergo a complete anaerobic phosphorus release and aerobic phosphorus absorption process, which has a "group effect", improves the phosphorus removal capacity of the treatment system and reduces the oxygen demand for organic matter degradation.

[0021] S2, main reaction stage:

[0022] S2-1, the wastewater treated in step S1-4 first enters the second-stage selection tank and then is transported to the second-stage aerobic tank, where the wastewater mainly undergoes short-range nitrification reaction, anaerobic ammonia oxidation reaction, partial short-range denitrification reaction and organic matter degradation;

[0023] S2-2, the wastewater treated in step S2-1 enters the second-stage anoxic tank, where the wastewater mainly undergoes short-range denitrification reaction, anaerobic ammonium oxidation reaction and partial denitrification reaction;

[0024] S2-3, the wastewater treated in step S2-2 enters the second-stage sedimentation tank, and the sludge at the bottom of the second-stage sedimentation tank is concentrated to a solid content of 12-20g / L by a solid-liquid separation and concentration device, and the nitrite-oxidizing bacteria (AOB), anaerobic ammonia-oxidizing bacteria (AnAOB), and short-range denitrifying bacteria in the mud-water mixture are effectively intercepted, and the intercepted dominant bacteria are lifted and returned to the first selection tank, the first aerobic tank zone B, and the second selection tank by an air lift device, so as to maintain a high concentration of dominant bacteria in the pretreatment stage and the main reaction stage, thereby ensuring the removal effect of ammonia nitrogen and TN;

[0025] S3, stable water discharge stage:

[0026] S3-1, the wastewater treated in step S2-3 enters the three-stage aerobic pool, the remaining organic matter in the wastewater is further degraded in the three-stage aerobic pool, the remaining small amount of ammonia nitrogen and nitrite nitrogen in the wastewater is oxidized into nitrate nitrogen, and the polyphosphate bacteria perform aerobic phosphorus absorption reaction in the three-stage aerobic pool;

[0027] Control the dissolved oxygen concentration of wastewater in the three-stage aerobic tank to 2-3 mg / L;

[0028] S3-2, the wastewater treated in step S3-1 enters the three-stage sedimentation tank, and the sludge at the bottom of the three-stage sedimentation tank is concentrated to a solid content of 12-20 g / L by a solid-liquid separation and concentration device, the sludge in the three-stage sedimentation tank is effectively intercepted, and the intercepted activated sludge containing aerobic bacteria is returned to the first aerobic tank area A and the third aerobic tank by an air stripping device to maintain the concentration of organic matter-degrading aerobic bacteria in the two aerobic areas, thereby improving the reaction rate of the aerobic tank;

[0029] The treated wastewater is discharged steadily from the three-stage sedimentation tank.

[0030] Preferably, in step S1-3, the C / N ratio of the treated wastewater in zone A of the aerobic tank is controlled to be less than 0.7.

[0031] Preferably, in step S1-4, the dissolved oxygen concentration in the wastewater in zone B of the aerobic pool is controlled to be 0.5-0.7 mg / L, and the pH is controlled to be 7.5-8.0.

[0032] Note: The purpose of controlling the dissolved oxygen and pH value in the wastewater in Zone B of the first aerobic tank is to inhibit the growth of nitrite oxidizing bacteria, so that the ammonia nitrogen in the water will only undergo nitrite reaction and further organic matter degradation reaction in Zone B of the first aerobic tank, accumulate nitrite nitrogen, the anaerobic ammonia oxidation substrate required for subsequent reactions, and make nitrite-oxidizing bacteria (AOB) the dominant bacteria, thereby achieving nitrite nitrogen enrichment.

[0033] Preferably, in step S2-1, the dissolved oxygen concentration in the second-stage aerobic tank is controlled to be 0.4-0.6 mg / L and the pH is 7.5-8.0, and in step S2-2, the dissolved oxygen concentration in the second-stage anoxic tank is controlled to be 0.3-0.5 mg / L and the pH is 7.5-8.0.

[0034] Preferably, in step S1-1, the concentrated sludge intercepted by the second-stage sedimentation tank in step S2-3 and the nitrification liquid returned from the end of zone B of the first-stage aerobic tank in step S1-4 are returned to the first-stage selection tank and enter the first-stage anoxic tank together with the high-concentration ammonia nitrogen wastewater in the first-stage selection tank.

[0035] Preferably, in step S2-1, the sludge intercepted and concentrated in the second-stage sedimentation tank in step S2-3 is returned to the second-stage selection tank and then enters the second-stage aerobic tank together with the wastewater in the second-stage selection tank.

[0036] Description: The concentrated sludge intercepted in the second-stage sedimentation tank in step S2-3 is returned to the second-stage selection tank and then enters the second-stage aerobic tank together with the wastewater in the second-stage selection tank to maintain the high concentration of nitrite bacteria (AOB), short-range denitrifying bacteria, and anaerobic ammonia oxidizing bacteria in the main reaction stage, thereby improving the anaerobic ammonia oxidation denitrification rate in the main reaction stage.

[0037] Preferably, in step S3-1, before the wastewater enters the three-stage aerobic tank, the sludge concentrated in the three-stage sedimentation tank in step S3-2 is firstly intercepted and mixed with the wastewater before entering the three-stage aerobic tank.

[0038] Note: Before the wastewater enters the three-stage aerobic tank, the concentrated sludge intercepted and concentrated by the three-stage sedimentation tank in step S3-2 is mixed with the wastewater before entering the three-stage aerobic tank to maintain a high concentration of heterotrophic aerobic bacteria in the three-stage aerobic tank during the stable effluent stage, thereby improving the removal rate of organic matter in the three-stage aerobic tank.

[0039] Preferably, the first-stage selection tank, the first-stage anoxic tank, the first-stage anaerobic tank, the second-stage selection tank, the second-stage aerobic tank and the second-stage anoxic tank are all provided with an aeration agitator.

[0040] Preferably, a low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment system is applied to the above-mentioned low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process, the system includes a pretreatment mechanism, a main reaction mechanism and a terminal stabilization treatment mechanism;

[0041] The pretreatment mechanism includes a selection tank, an anoxic tank, an anaerobic tank, an aerobic tank area A, and an aerobic tank area B, which are arranged in sequence;

[0042] A selection tank is connected to an anoxic tank, and an anoxic tank is connected to an anaerobic tank;

[0043] A nitrification liquid return channel is provided between the aerobic tank B section and the selection tank section;

[0044] An aerobic tank inlet stripping zone and an aerobic tank return stripping zone are provided between the first anaerobic tank and the first aerobic tank zone A;

[0045] The first section of anaerobic tank is connected to the input end of the water inlet stripping zone of the first section of aerobic tank, the output end of the water inlet stripping zone of the first section of aerobic tank is connected to the A zone of the first section of aerobic tank, the output end of the return stripping zone of the first section of aerobic tank is connected to the A zone of the first section of aerobic tank, and the input end of the return stripping zone of the first section of aerobic tank is connected to a nitrification liquid return channel;

[0046] A first stripping device is provided in the water inlet stripping area of ​​the first aerobic tank, and a first stripping gas control valve is provided on the gas supply pipe of the first stripping device; a second stripping device is provided in the reflux stripping area of ​​the first aerobic tank, and a second stripping gas control valve is provided on the gas supply pipe of the second stripping device;

[0047] A first aeration agitator is provided at the bottom of the first selection tank, and a first aeration agitator gas control valve is provided on the air supply pipe of the first aeration agitator; a second aeration agitator is provided at the bottom of the first anoxic tank, and a second aeration agitator gas control valve is provided on the air supply pipe of the second aeration agitator; a third aeration agitator is provided at the bottom of the first anaerobic tank, and a third aeration agitator gas control valve is provided on the air supply pipe of the third aeration agitator;

[0048] A first aeration device is provided at the bottom of the aerobic pool A zone, and a first aeration gas control valve is provided on the air supply pipe of the first aeration device; a second aeration device is provided at the bottom of the aerobic pool B zone, and a second aeration gas control valve is provided on the air supply pipe of the second aeration device;

[0049] The main reaction mechanism includes a second-stage selection tank, a second-stage aerobic tank, a second-stage anoxic tank, and a second-stage sedimentation tank which are arranged in sequence;

[0050] A fourth aeration agitator is provided at the bottom of the second-stage selection tank, and a fourth aeration agitator gas control valve is provided on the gas supply pipe of the fourth aeration agitator;

[0051] The second-stage aerobic tank is provided with a fifth aeration agitator, and the air supply pipe of the fifth aeration agitator is provided with a fifth aeration agitator gas control valve;

[0052] The second stage anoxic tank is provided with a sixth aeration agitator, and the gas supply pipe of the sixth aeration agitator is provided with a sixth aeration agitator gas control valve;

[0053] The second-stage sedimentation tank is provided with a first solid-liquid separation and concentration device and a first aeration and purge device, and the air supply pipe of the first aeration and purge device is provided with a first purge gas control valve;

[0054] The first aerobic tank area B is connected to the second selection tank, the second aerobic tank is connected to the second anoxic tank, and the second anoxic tank is connected to the second sedimentation tank;

[0055] Between the second-stage selection tank and the second-stage aerobic tank are provided a second-stage aerobic tank water inlet gas stripping area and a second-stage aerobic tank return gas stripping area;

[0056] A third gas stripping device is provided in the water inlet gas stripping area of ​​the second-stage aerobic tank, and a third gas stripping gas control valve is provided on the gas supply pipe of the third gas stripping device; a fourth gas stripping device is provided in the reflux gas stripping area of ​​the second-stage aerobic tank, and a fourth gas stripping gas control valve is provided on the gas supply pipe of the fourth gas stripping device;

[0057] The second-stage selection tank is connected to the input end of the second-stage aerobic tank water inlet stripping zone, the output end of the second-stage aerobic tank water inlet stripping zone is connected to the second-stage aerobic tank, and the output end of the second-stage aerobic tank reflux stripping zone is connected to the second-stage aerobic tank;

[0058] A fifth gas stripping device is provided in the second-stage sedimentation tank, and the fifth gas stripping device is connected to the first-stage selection tank, the first-stage aerobic tank zone B and the second-stage selection tank through a dominant bacteria return pipe, and a fifth gas stripping gas control valve is provided on the gas supply pipe of the fifth gas stripping device;

[0059] The dominant bacteria return pipe is located in the first selection tank, the first aerobic tank B area and the output pipe of the second selection tank, and has a first return control valve, a second return control valve and a third return control valve respectively;

[0060] The input end of the recirculation stripping zone of the second-stage aerobic tank is connected to the second-stage anoxic tank and an anaerobic ammonia oxidation internal recirculation channel is provided;

[0061] The final stage stabilization treatment mechanism includes a three-stage aerobic tank water inlet gas stripping area, a three-stage aerobic tank, and a three-stage sedimentation tank arranged in sequence;

[0062] A second solid-liquid separation and concentration device is provided in the three-stage sedimentation tank, a second aeration and purge device is provided in the three-stage sedimentation tank, and a second purge gas control valve is provided on the air supply pipe of the second aeration and purge device;

[0063] A third aeration device is provided in the three-stage aerobic pool, and a third aeration gas control valve is provided on the gas supply pipe of the third aeration device;

[0064] A sixth gas stripping device is provided in the water inlet gas stripping area of ​​the three-stage aerobic pool, and a sixth gas stripping gas control valve is provided on the gas supply pipe of the sixth gas stripping device;

[0065] The second-stage sedimentation tank is connected to the input end of the water inlet stripping zone of the third-stage aerobic tank, the output end of the water inlet stripping zone of the third-stage aerobic tank is connected to the third-stage aerobic tank, and the third-stage aerobic tank is connected to the third-stage sedimentation tank;

[0066] The third-stage sedimentation tank is provided with a seventh gas stripping device, which is connected to the third-stage aerobic tank and the first-stage aerobic tank area A through an aerobic bacteria return pipe, and the gas supply pipe of the seventh gas stripping device is provided with a seventh gas stripping gas control valve;

[0067] The aerobic bacteria return pipe is located in the A zone of the first stage aerobic pool and the output pipe of the third stage aerobic pool is respectively provided with a fourth return control valve and a fifth return control valve.

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] 1. The whole system of the present invention has good adaptability to the load shock and water quality shock of the incoming water. Even if the anaerobic ammonium oxidation reaction is suppressed by the shock under sudden circumstances, there is still a short-range nitrification and denitrification with low energy consumption, low operating cost and small footprint as a guarantee. The anaerobic ammonium oxidation reaction recovers quickly after being suppressed by the shock, which can ensure that the system effluent is stable and meets the standards.

[0070] 2. The high-ammonia nitrogen wastewater treatment process of the present invention integrates precise control, high solid load solid-liquid separation and concentration technology, and high-rate pneumatic lifting internal and external reflux circulation technology on the basis of a multi-stage process combination, so that it integrates the advantages of traditional A2 / O, SBR, oxidation ditch and MBR, and can achieve synchronous short-range nitrification and denitrification, short-range denitrification, and anaerobic ammonia oxidation functions that are difficult to achieve in these processes, greatly reducing the energy consumption, drug consumption, operating cost and floor space of high-ammonia nitrogen wastewater treatment;

[0071] 3. The treatment process of the present invention adopts the pneumatic lifting reflux circulation technology with a large proportion of reflux, which can make the treatment process have similar characteristics to the oxidation ditch. While achieving oxygenation for the aerobic pool, the entire biochemical pool is in a completely mixed state to obtain a good treatment effect, and no additional nitrification liquid reflux pump is required, which greatly reduces energy consumption; the integrated application of high solid load solid-liquid separation and concentration technology and high-rate pneumatic lifting internal and external reflux circulation technology ensures that the sludge concentration in each biochemical reaction zone can be as high as 8-10g / L like MBR, so that the volume load of each functional area is increased and the sludge load is reduced due to the increase in bacterial concentration, thereby enhancing the impact resistance of the biochemical system and reducing the floor space. At the same time, the air intake and air intake time of each area can be reasonably adjusted according to the changing needs of the influent water quality and water volume, so as to reasonably distribute each functional area and section, so that it has the advantages of flexible adjustment of SBR.

[0072] 4. Under the same influent (high-pollution, high-concentration ammonia nitrogen wastewater) and effluent conditions, the floor space of the BM-AAO process of the present invention is only 40% of that of the traditional activated sludge process, the carbon source addition is saved by 100%, the energy consumption is saved by 60%, and the sludge output is reduced by 80%. It can save considerable operating costs and floor space for the treatment of high-pollution, high-concentration wastewater such as steel, fertilizer, inorganic chemical industry, coal chemical industry, ferroalloy, glass manufacturing, landfill leachate, leather, meat processing, livestock and poultry breeding, etc., and solve the problem of land shortage and high operating costs of wastewater treatment systems in these industries. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 It is a schematic diagram of the structural principle of the high ammonia nitrogen wastewater treatment equipment in the present invention;

[0074] Figure 2 It is a schematic diagram of the structural principle of the high ammonia nitrogen wastewater treatment equipment in the present invention;

[0075] Figure 3 It is a schematic diagram of the structural principle of the high ammonia nitrogen wastewater treatment equipment in the present invention.

[0076] In the figure, 1-a first selection tank, 11-a first aeration agitator, 12-a first aeration agitation gas control valve, 13-a first reflux control valve, 2-a first anoxic tank, 21-a second aeration agitator, 22-a second aeration agitation gas control valve, 3-a first anaerobic tank, 31-a third aeration agitator, 32-a third aeration agitation gas control valve, 4-a first aerobic tank water inlet stripping area, 41-a first stripping device, 42-a first stripping gas control valve, 5-a first aerobic tank reflux stripping area, 51-a second stripping device, 52-a second stripping gas control valve, 6-a first aerobic tank A area, 61- The first aeration device, 62-the first aeration gas control valve, 63-the fourth reflux control valve, 7-the first aerobic pool B zone, 71-the second aeration device, 72-the second aeration gas control valve, 73-the second reflux control valve, 8-the second selection pool, 81-the fourth aeration agitator, 82-the fourth aeration agitation gas control valve, 83-the third reflux control valve, 9-the second aerobic pool water inlet stripping zone, 91-the third stripping device, 92-the third stripping gas control valve, 100-the second aerobic pool reflux stripping zone, 101-the fourth stripping device, 102-the fourth stripping gas control valve, 110-the second aerobic tank, 111-fifth aeration agitator, 112-fifth aeration agitator gas control valve, 120-second anoxic tank, 121-sixth aeration agitator, 122-sixth aeration agitator gas control valve, 130-second sedimentation tank, 131-first solid-liquid separation and concentration device, 132-first aeration purge device, 133-first purge gas control valve, 134-fifth gas stripping device, 135-fifth gas stripping gas control valve, 140-water stripping zone of the third aerobic tank, 141-sixth gas stripping device, 142-sixth gas stripping gas control valve, 150-third aerobic tank, 151 -The third aeration device, 152-the third aeration gas control valve, 153-the fifth reflux control valve, 160-the third sedimentation tank, 161-the second solid-liquid separation and concentration device, 162-the second aeration purge device, 163-the second purge gas control valve, 164-the seventh gas lift device, 165-the seventh gas lift gas control valve, 17-the first nitrification liquid reflux channel, 18-the anaerobic ammonia oxidation internal reflux channel, 19-the dominant bacteria reflux pipe, 20-the aerobic bacteria reflux pipe, 210-precision control blast, 991-pretreatment mechanism, 992-the main reaction mechanism, 993-the final stage stabilization treatment mechanism. DETAILED DESCRIPTION

[0077] Combine the following Figure 1-Figure 3 The present invention is described in detail. For the convenience of description, the directions mentioned below are defined as follows: the up, down, left, right, front and back directions mentioned below are Figure 1 The up-down, left-right, front-back directions of the projection relationship itself are consistent.

[0078] Embodiment 1:

[0079] A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process comprises the following steps:

[0080] S1, pre-processing stage:

[0081] S1-1, high concentration ammonia nitrogen wastewater first enters a first anoxic tank from a first selection tank for denitrification and short-range denitrification reaction;

[0082] S1-2, the wastewater treated in step S1-1 enters an anaerobic tank, where polyphosphate-accumulating bacteria are used to rapidly degrade and absorb organic matter in the wastewater under anaerobic conditions;

[0083] S1-3, the wastewater treated in step S1-2 enters the aerobic pool A for further degradation of organic matter, absorption of phosphorus under aerobic conditions and accumulation of nitrite nitrogen by short-range nitrification reaction;

[0084] The C / N ratio of the treated wastewater in zone A of the first aerobic pool is 0.7;

[0085] S1-4, the wastewater treated in step S1-3 enters zone B of the first aerobic pool to inhibit the growth of nitrite oxidizing bacteria, so that the ammonia nitrogen in the water only undergoes nitrite reaction and further organic matter degradation reaction in zone B of the first aerobic pool, and accumulates nitrite nitrogen, a substrate for anaerobic ammonia oxidation required for subsequent reactions;

[0086] The dissolved oxygen concentration in the wastewater in the aerobic tank B is controlled to be 0.5 mg / L and the pH is 7.5;

[0087] S2, main reaction stage:

[0088] S2-1, the wastewater treated in step S1-4 first enters the second-stage selection tank and then is transported to the second-stage aerobic tank, where the wastewater mainly undergoes short-range nitrification reaction, anaerobic ammonia oxidation reaction, partial short-range denitrification reaction and organic matter degradation;

[0089] Control the dissolved oxygen concentration in the second-stage aerobic tank to 0.4 mg / L and the pH to 7.5;

[0090] S2-2, the wastewater treated in step S2-1 enters the second-stage anoxic tank, where the wastewater mainly undergoes short-range denitrification reaction, anaerobic ammonium oxidation reaction and partial denitrification reaction;

[0091] The dissolved oxygen concentration in the second-stage anoxic tank was controlled to be 0.3 mg / L and the pH was 7.5;

[0092] S2-3, the wastewater treated in step S2-2 enters the second-stage sedimentation tank, and the sludge at the bottom of the second-stage sedimentation tank is concentrated to a solid content of 12 g / L using a solid-liquid separation and concentration device;

[0093] S3, stable water discharge stage:

[0094] S3-1, the wastewater treated in step S2-3 enters the three-stage aerobic pool, the remaining organic matter in the wastewater is further degraded in the three-stage aerobic pool, the remaining small amount of ammonia nitrogen and nitrite nitrogen in the wastewater is oxidized into nitrate nitrogen, and the polyphosphate bacteria perform aerobic phosphorus absorption reaction in the three-stage aerobic pool;

[0095] Control the dissolved oxygen concentration of wastewater in the three-stage aerobic tank to 2 mg / L;

[0096] S3-2, the wastewater treated in step S3-1 enters the three-stage sedimentation tank, and the sludge at the bottom of the three-stage sedimentation tank is concentrated to a solid content of 12g / L using a solid-liquid separation and concentration device;

[0097] The treated wastewater is discharged steadily from the three-stage sedimentation tank.

[0098] In step S1-1, the concentrated sludge intercepted by the second-stage sedimentation tank in step S2-3 and the nitrification liquid returned from the end of zone B of the first-stage aerobic tank in step S1-4 are returned to the first-stage selection tank and enter the first-stage anoxic tank together with the high-concentration ammonia nitrogen wastewater in the first-stage selection tank.

[0099] In step S2-1, the sludge intercepted and concentrated in the second-stage sedimentation tank in step S2-3 is returned to the second-stage selection tank and then enters the second-stage aerobic tank together with the wastewater in the second-stage selection tank.

[0100] In step S3-1, before the wastewater enters the three-stage aerobic tank, the concentrated sludge intercepted and concentrated in the three-stage sedimentation tank in step S3-2 is mixed with the wastewater and then enters the three-stage aerobic tank.

[0101] The first-stage selection tank, the first-stage anoxic tank, the first-stage anaerobic tank, the second-stage selection tank, the second-stage aerobic tank and the second-stage anoxic tank are all equipped with aeration stirrers.

[0102] Embodiment 2:

[0103] A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process comprises the following steps:

[0104] S1, pre-processing stage:

[0105] S1-1, high concentration ammonia nitrogen wastewater first enters a first anoxic tank from a first selection tank for denitrification and short-range denitrification reaction;

[0106] S1-2, the wastewater treated in step S1-1 enters an anaerobic tank, where polyphosphate-accumulating bacteria are used to rapidly degrade and absorb organic matter in the wastewater under anaerobic conditions;

[0107] S1-3, the wastewater treated in step S1-2 enters the aerobic pool A for further degradation of organic matter, absorption of phosphorus under aerobic conditions and accumulation of nitrite nitrogen by short-range nitrification reaction;

[0108] The C / N ratio of the treated wastewater in zone A of the first aerobic pool is 0.65;

[0109] S1-4, the wastewater treated in step S1-3 enters zone B of the first aerobic pool to inhibit the growth of nitrite oxidizing bacteria, so that the ammonia nitrogen in the water only undergoes nitrite reaction and further organic matter degradation reaction in zone B of the first aerobic pool, and accumulates nitrite nitrogen, a substrate for anaerobic ammonia oxidation required for subsequent reactions;

[0110] The dissolved oxygen concentration in the wastewater in the aerobic tank B is controlled to be 0.6 mg / L and the pH is 8.0;

[0111] S2, main reaction stage:

[0112] S2-1, the wastewater treated in step S1-4 first enters the second-stage selection tank and then is transported to the second-stage aerobic tank, where the wastewater mainly undergoes short-range nitrification reaction, anaerobic ammonia oxidation reaction, partial short-range denitrification reaction and organic matter degradation;

[0113] Control the dissolved oxygen concentration in the second-stage aerobic pool to 0.5 mg / L and the pH to 8.0;

[0114] S2-2, the wastewater treated in step S2-1 enters the second-stage anoxic tank, where the wastewater mainly undergoes short-range denitrification reaction, anaerobic ammonium oxidation reaction and partial denitrification reaction;

[0115] The dissolved oxygen concentration in the second-stage anoxic tank was controlled to be 0.4 mg / L and the pH was 8.0;

[0116] S2-3, the wastewater treated in step S2-2 enters the second-stage sedimentation tank, and the sludge at the bottom of the second-stage sedimentation tank is concentrated to a solid content of 16 g / L using a solid-liquid separation and concentration device;

[0117] S3, stable water discharge stage:

[0118] S3-1, the wastewater treated in step S2-3 enters the three-stage aerobic pool, the remaining organic matter in the wastewater is further degraded in the three-stage aerobic pool, the remaining small amount of ammonia nitrogen and nitrite nitrogen in the wastewater is oxidized into nitrate nitrogen, and the polyphosphate bacteria perform aerobic phosphorus absorption reaction in the three-stage aerobic pool;

[0119] Control the dissolved oxygen concentration of wastewater in the three-stage aerobic tank to 2.5 mg / L;

[0120] S3-2, the wastewater treated in step S3-1 enters the three-stage sedimentation tank, and the sludge at the bottom of the three-stage sedimentation tank is concentrated to a solid content of 16g / L using a solid-liquid separation and concentration device;

[0121] The treated wastewater is discharged steadily from the three-stage sedimentation tank.

[0122] In step S1-1, the concentrated sludge intercepted by the second-stage sedimentation tank in step S2-3 and the nitrification liquid returned from the end of zone B of the first-stage aerobic tank in step S1-4 are returned to the first-stage selection tank and enter the first-stage anoxic tank together with the high-concentration ammonia nitrogen wastewater in the first-stage selection tank.

[0123] In step S2-1, the sludge intercepted and concentrated in the second-stage sedimentation tank in step S2-3 is returned to the second-stage selection tank and then enters the second-stage aerobic tank together with the wastewater in the second-stage selection tank.

[0124] In step S3-1, before the wastewater enters the three-stage aerobic tank, the concentrated sludge intercepted and concentrated in the three-stage sedimentation tank in step S3-2 is mixed with the wastewater and then enters the three-stage aerobic tank.

[0125] The first-stage selection tank, the first-stage anoxic tank, the first-stage anaerobic tank, the second-stage selection tank, the second-stage aerobic tank and the second-stage anoxic tank are all equipped with aeration stirrers.

[0126] Embodiment 3:

[0127] A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process comprises the following steps:

[0128] S1, pre-processing stage:

[0129] S1-1, high concentration ammonia nitrogen wastewater first enters a first anoxic tank from a first selection tank for denitrification and short-range denitrification reaction;

[0130] S1-2, the wastewater treated in step S1-1 enters an anaerobic tank, where polyphosphate-accumulating bacteria are used to rapidly degrade and absorb organic matter in the wastewater under anaerobic conditions;

[0131] S1-3, the wastewater treated in step S1-2 enters the aerobic pool A for further degradation of organic matter, absorption of phosphorus under aerobic conditions and accumulation of nitrite nitrogen by short-range nitrification reaction;

[0132] The C / N ratio of the treated wastewater in zone A of the first aerobic pool is 0.6;

[0133] S1-4, the wastewater treated in step S1-3 enters zone B of the first aerobic pool to inhibit the growth of nitrite oxidizing bacteria, so that the ammonia nitrogen in the water only undergoes nitrite reaction and further organic matter degradation reaction in zone B of the first aerobic pool, and accumulates nitrite nitrogen, a substrate for anaerobic ammonia oxidation required for subsequent reactions;

[0134] The dissolved oxygen concentration in the wastewater in the aerobic tank B is controlled to be 0.7 mg / L and the pH is 8.0;

[0135] S2, main reaction stage:

[0136] S2-1, the wastewater treated in step S1-4 first enters the second-stage selection tank and then is transported to the second-stage aerobic tank, where the wastewater mainly undergoes short-range nitrification reaction, anaerobic ammonia oxidation reaction, partial short-range denitrification reaction and organic matter degradation;

[0137] Control the dissolved oxygen concentration in the second-stage aerobic pool to 0.6 mg / L and the pH to 8.0;

[0138] S2-2, the wastewater treated in step S2-1 enters the second-stage anoxic tank, where the wastewater mainly undergoes short-range denitrification reaction, anaerobic ammonium oxidation reaction and partial denitrification reaction;

[0139] The dissolved oxygen concentration in the second-stage anoxic tank was controlled to be 0.5 mg / L and the pH was 8.0;

[0140] S2-3, the wastewater treated in step S2-2 enters the second-stage sedimentation tank, and the sludge at the bottom of the second-stage sedimentation tank is concentrated to a solid content of 20g / L using a solid-liquid separation and concentration device;

[0141] S3, stable water discharge stage:

[0142] S3-1, the wastewater treated in step S2-3 enters the three-stage aerobic pool, the remaining organic matter in the wastewater is further degraded in the three-stage aerobic pool, the remaining small amount of ammonia nitrogen and nitrite nitrogen in the wastewater is oxidized into nitrate nitrogen, and the polyphosphate bacteria perform aerobic phosphorus absorption reaction in the three-stage aerobic pool;

[0143] Control the dissolved oxygen concentration of wastewater in the three-stage aerobic tank to 3 mg / L;

[0144] S3-2, the wastewater treated in step S3-1 enters the three-stage sedimentation tank, and the sludge at the bottom of the three-stage sedimentation tank is concentrated to a solid content of 20g / L using a solid-liquid separation and concentration device;

[0145] The treated wastewater is discharged steadily from the three-stage sedimentation tank.

[0146] In step S1-1, the concentrated sludge intercepted by the second-stage sedimentation tank in step S2-3 and the nitrification liquid returned from the end of zone B of the first-stage aerobic tank in step S1-4 are returned to the first-stage selection tank and enter the first-stage anoxic tank together with the high-concentration ammonia nitrogen wastewater in the first-stage selection tank.

[0147] In step S2-1, the sludge intercepted and concentrated in the second-stage sedimentation tank in step S2-3 is returned to the second-stage selection tank and then enters the second-stage aerobic tank together with the wastewater in the second-stage selection tank.

[0148] In step S3-1, before the wastewater enters the three-stage aerobic tank, the concentrated sludge intercepted and concentrated in the three-stage sedimentation tank in step S3-2 is mixed with the wastewater and then enters the three-stage aerobic tank.

[0149] The first-stage selection tank, the first-stage anoxic tank, the first-stage anaerobic tank, the second-stage selection tank, the second-stage aerobic tank and the second-stage anoxic tank are all equipped with aeration stirrers.

[0150] A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment system is applied to a low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process in the above-mentioned embodiments 1 to 3, and the system includes a pretreatment mechanism 991, a main reaction mechanism 992 and a terminal stabilization treatment mechanism 993;

[0151] The pretreatment mechanism 991 includes a selection tank 1, an anoxic tank 2, an anaerobic tank 3, an aerobic tank A zone 6, and an aerobic tank B zone 7 which are arranged in sequence;

[0152] A selection tank 1 is connected to an anoxic tank 2, and an anoxic tank 2 is connected to an anaerobic tank 3;

[0153] A nitrification liquid return channel 17 is provided between the aerobic tank B zone 7 and the selection tank 1;

[0154] An aerobic tank inlet stripping zone 4 and an aerobic tank return stripping zone 5 are provided between the first anaerobic tank 3 and the first aerobic tank A zone 6;

[0155] The first section of anaerobic tank 3 is connected to the input end of the first section of aerobic tank water inlet stripping zone 4, the output end of the first section of aerobic tank water inlet stripping zone 4 is connected to the first section of aerobic tank A zone 6, the output end of the first section of aerobic tank reflux stripping zone 5 is connected to the first section of aerobic tank A zone 6, and the input end of the first section of aerobic tank reflux stripping zone 5 is connected to a section of nitrification liquid reflux channel 17;

[0156] A first stripping device 41 is provided in the first aerobic tank water inlet stripping zone 4, and a first stripping gas control valve 42 is provided on the gas supply pipe of the first stripping device 41; a second stripping device 51 is provided in the first aerobic tank reflux stripping zone 5, and a second stripping gas control valve 52 is provided on the gas supply pipe of the second stripping device 51;

[0157] A first aeration agitator 11 is provided at the bottom of the first selection tank 1, and a first aeration agitator 11 has a first aeration agitator gas control valve 12 on its air supply pipe; a second aeration agitator 21 is provided at the bottom of the first anoxic tank 2, and a second aeration agitator 21 has a second aeration agitator gas control valve 22 on its air supply pipe; a third aeration agitator 31 is provided at the bottom of the first anaerobic tank 3, and a third aeration agitator 31 has a third aeration agitator gas control valve 32 on its air supply pipe;

[0158] A first aeration device 61 is provided at the bottom of the aerobic tank A zone 6, and a first aeration gas control valve 62 is provided on the air supply pipe of the first aeration device 61; a second aeration device 71 is provided at the bottom of the aerobic tank B zone 7, and a second aeration gas control valve 72 is provided on the air supply pipe of the second aeration device 71;

[0159] The main reaction mechanism 992 includes a second-stage selection tank 8, a second-stage aerobic tank 110, a second-stage anoxic tank 120, and a second-stage sedimentation tank 130 which are arranged in sequence;

[0160] A fourth aeration agitator 81 is provided at the bottom of the second-stage selection tank 8, and a fourth aeration agitator gas control valve 82 is provided on the gas supply pipe of the fourth aeration agitator 81;

[0161] A fifth aeration agitator 111 is provided in the second-stage aerobic tank 110, and a fifth aeration agitator gas control valve 112 is provided on the gas supply pipe of the fifth aeration agitator 111;

[0162] A sixth aeration agitator 121 is provided in the second stage anoxic tank 120, and a sixth aeration agitator gas control valve 122 is provided on the gas supply pipe of the sixth aeration agitator 121;

[0163] The second-stage sedimentation tank 130 is provided with a first solid-liquid separation and concentration device 131 and a first aeration and purge device 132. The gas supply pipe of the first aeration and purge device 132 is provided with a first purge gas control valve 133.

[0164] The first aerobic tank B area 7 is connected to the second selection tank 8, the second aerobic tank 110 is connected to the second anoxic tank 120, and the second anoxic tank 120 is connected to the second sedimentation tank 130;

[0165] A second-stage aerobic tank water inlet stripping zone 9 and a second-stage aerobic tank return stripping zone 100 are provided between the second-stage selection tank 8 and the second-stage aerobic tank 110;

[0166] A third stripping device 91 is provided in the second-stage aerobic tank water inlet stripping zone 9, and a third stripping gas control valve 92 is provided on the gas supply pipe of the third stripping device 91. A fourth stripping device 101 is provided in the second-stage aerobic tank reflux stripping zone 100, and a fourth stripping gas control valve 102 is provided on the gas supply pipe of the fourth stripping device 101.

[0167] The second-stage selection pool 8 is connected to the input end of the second-stage aerobic pool water inlet stripping zone 9, the output end of the second-stage aerobic pool water inlet stripping zone 9 is connected to the second-stage aerobic pool 110, and the output end of the second-stage aerobic pool reflux stripping zone 100 is connected to the second-stage aerobic pool 110;

[0168] A fifth gas stripping device 134 is provided in the second-stage sedimentation tank 130. The fifth gas stripping device 134 is connected to the first-stage selection tank 1, the first-stage aerobic tank B zone 7 and the second-stage selection tank 8 through the dominant bacteria return pipe 19. A fifth gas stripping gas control valve 135 is provided on the gas supply pipe of the fifth gas stripping device 134.

[0169] The dominant bacteria return pipe 19 is located on the output pipes of the first selection tank 1, the first aerobic tank B zone 7 and the second selection tank 8, and has a first return control valve 13, a second return control valve 73 and a third return control valve 83 respectively;

[0170] The input end of the second-stage aerobic tank recirculation stripping zone 100 is connected to the second-stage anoxic tank 120 and is provided with an anaerobic ammonium oxidation internal recirculation channel 18;

[0171] The final stage stabilization treatment mechanism 993 includes a three-stage aerobic tank water inlet stripping zone 140, a three-stage aerobic tank 150, and a three-stage sedimentation tank 160 which are arranged in sequence;

[0172] A second solid-liquid separation and concentration device 161 is provided in the three-stage sedimentation tank 160, a second aeration and purge device 162 is provided in the three-stage sedimentation tank 160, and a second purge gas control valve 163 is provided on the gas supply pipe of the second aeration and purge device 162;

[0173] A third aeration device 151 is provided in the three-stage aerobic pool 150, and a third aeration gas control valve 152 is provided on the gas supply pipe of the third aeration device 151;

[0174] A sixth gas stripping device 141 is provided in the water inlet gas stripping area 140 of the three-stage aerobic tank, and a sixth gas stripping gas control valve 142 is provided on the gas supply pipe of the sixth gas stripping device 141;

[0175] The second-stage sedimentation tank 130 is connected to the input end of the third-stage aerobic tank water inlet stripping zone 140, the output end of the third-stage aerobic tank water inlet stripping zone 140 is connected to the third-stage aerobic tank 150, and the third-stage aerobic tank 150 is connected to the third-stage sedimentation tank 160;

[0176] The third-stage sedimentation tank 160 is provided with a seventh gas stripping device 164, which is connected to the third-stage aerobic tank 150 and the first-stage aerobic tank A zone 6 through an aerobic bacteria return pipe 20, and a seventh gas stripping gas control valve 165 is provided on the gas supply pipe of the seventh gas stripping device 164;

[0177] The aerobic bacteria return pipe 20 is located in the first-stage aerobic pool A zone 6 and the output pipe of the third-stage aerobic pool 150 is provided with a fourth return control valve 63 and a fifth return control valve 153 respectively.

[0178] In the actual wastewater treatment process, short-term nitrification and denitrification is the process in which denitrifying bacteria reduce nitrite nitrogen to nitrogen gas after nitrosifying bacteria (AOB) complete the nitrification reaction. The short-term nitrification and denitrification reaction consumes 3.43 mg of dissolved oxygen, 3.57 mg of alkalinity and 1.71 mg of COD for every 1 mg of ammonia removed. Compared with the traditional nitrification and denitrification process, it can reduce 25% of dissolved oxygen consumption and 40% of COD consumption, and reduce 25% to 34% of sludge production in the nitrification process, and reduce about 50% of sludge production in the denitrification process, which can significantly reduce the cost of wastewater and sludge treatment;

[0179] Short-term nitrification and denitrification reaction formula:

[0180] Short-range nitrification: NH4 + +1.5O2→NO2 - +2H + +1.87H2O

[0181] Denitrification: 6NO2 - +3CH3OH+3CO2→3N2↑+6HCO3 - +3H2O

[0182] Under suitable anaerobic or anoxic conditions, ammonia nitrogen and nitrite nitrogen can undergo anaerobic ammonium oxidation reaction, and anaerobic ammonium oxidizing bacteria (AnAOB) convert ammonia nitrogen and nitrite into nitrogen gas. The use of anaerobic ammonium oxidation process to treat wastewater requires solving the problem of the source of nitrite, so it is often used in conjunction with a short-term nitrification reaction, that is, a short-term nitrification anaerobic ammonium oxidation reaction. After nitrite-oxidizing bacteria (AOB) complete the nitrification reaction to generate nitrite nitrogen, anaerobic ammonium oxidizing bacteria (AnAOB) convert nitrite nitrogen and ammonia nitrogen into nitrogen gas, eliminating the need for a denitrification process that occupies a large area and consumes a large amount of carbon source.

[0183] The short-range nitrification anaerobic ammonium oxidation reaction equation is:

[0184] Short-range nitrification: NH4 + +1.5O2→NO2 - +2H + +1.87H2O

[0185] Anaerobic ammonium oxidation: NH4 + +1.32NO2 - +0.066HCO3 - +0.13H + →1.02N2↑+0.26NO3 -+2.03H2O+0.066CH2O 0.5 N 0.15

[0186] The short-range nitrification plus anaerobic ammonia oxidation system biological denitrification process consumes 1.71 mg of dissolved oxygen and produces 0.11 g of nitrate nitrogen for every 1 mg of ammonia removed, and does not consume CODcr. Compared with the traditional nitrification and denitrification process, it can reduce 62.5% of dissolved oxygen consumption and 100% of CODcr consumption, and the sludge output can be reduced by about 90%, which can significantly reduce the energy consumption and cost of wastewater and sludge treatment, and reduce the floor space and investment cost of the biochemical system.

[0187] In high-concentration wastewater treatment systems, even if short-term nitrification plus anaerobic ammonium oxidation reactions are carried out, a certain amount of nitrate nitrogen will still be generated. In order to better control operating costs, after the short-term nitrification plus anaerobic ammonium oxidation reaction, the nitrate nitrogen can undergo a short-term denitrification reaction to generate nitrite nitrogen, which then undergoes anaerobic ammonium oxidation reaction with ammonia nitrogen, so that the TN of the effluent can be further reduced through anaerobic ammonium oxidation.

[0188] The short-range denitrification anaerobic ammonium oxidation reaction equation is:

[0189] Short-range denitrification: 1.32NO3 - +0.55CH3COO - +0.088NH4 + →1.32NO2 - +0.088C5H7NO2+0.66HCO3 - +0.198H + +0.264H2O

[0190] Anaerobic ammonium oxidation: NH4 + +1.32NO2 - +0.066HCO3 - +0.13H + →1.02N2↑+0.26NO3 - +2.03H2O+0.066CH2O 0.5 N 0.15

[0191] Coupling short-cut denitrification and anaerobic ammonium oxidation can reduce the amount of external carbon source and sludge production required for nitrate nitrogen treatment by 60.1% and 44.8%, respectively.

[0192] In summary, in order to better achieve high ammonia nitrogen wastewater treatment with low energy consumption, low drug consumption, low cost, low sludge production and small footprint, we must ensure that the treatment process obtains a good anaerobic ammonia oxidation environment so that the anaerobic ammonia oxidation reaction can be fully carried out.

[0193] The BM-AAO process adopts a multi-stage process combination, precise control, high solid load solid-liquid separation and concentration technology, and high-rate pneumatic lifting internal and external reflux circulation technology. It not only integrates the advantages of traditional A2 / O, SBR, oxidation ditch and MBR, but also has the synchronous short-range nitrification and denitrification, and anaerobic ammonia oxidation functions that are difficult for them to achieve.

[0194] All gas control valves in the present invention are controlled by the precise control air blast 210, which is a prior art.

[0195] In the actual application process of the present invention, when the high-concentration ammonia nitrogen wastewater enters, it is fully mixed with the dominant activated sludge intercepted and concentrated in the second-stage sedimentation tank 130 and the nitrification liquid returned from the end of the first-stage aerobic tank B zone 7, and then enters the first-stage anoxic tank 2 together for denitrification and short-range denitrification reaction;

[0196] After consuming a considerable portion of the organic matter carried in the wastewater, it enters the first anaerobic tank 3. The polyphosphate bacteria in the first anaerobic tank 3 are inhibited under anaerobic conditions and release phosphates in the body, generating energy to absorb and quickly degrade organic matter, so that the organic matter in the wastewater is further reduced;

[0197] The wastewater in the first stage anaerobic tank 3 then enters the first stage aerobic tank water inlet stripping zone 4, and the first stripping device 41 is used to transport the wastewater in the first stage aerobic tank water inlet stripping zone 4 to the first stage aerobic tank A zone 6 for further organic matter degradation, aerobic phosphorus absorption and short-range nitrification reaction;

[0198] After the C / N ratio of the wastewater in the first aerobic pool A zone 6 is less than 0.7, the wastewater in the first aerobic pool A zone 6 is transported to the first aerobic pool B zone 7, and the dissolved oxygen in the water in the first aerobic pool B zone 7 is controlled to be 0.6 mg / L and the pH is 8.0, so as to inhibit the growth of nitrite oxidizing bacteria, so that the ammonia nitrogen in the water almost only undergoes nitrosation reaction and further organic matter degradation reaction in the first aerobic pool B zone 7, and the nitrosating bacteria (AOB) become the dominant bacteria, thereby achieving the enrichment of nitrite nitrogen;

[0199] The first aeration agitator 11, the second aeration agitator 21 and the third aeration agitator 31 in each of the first selection tank 1, the first anoxic tank 2 and the first anaerobic tank 3 are respectively controlled by the first aeration agitator gas control valve 12, the second aeration agitator gas control valve 22 and the third aeration agitator gas control valve 32 to control the opening and closing of the first aeration agitator 11, the second aeration agitator 21 and the third aeration agitator 31 and the aeration amount, so as to prevent sludge from being deposited at the bottom of the first selection tank 1, the first anoxic tank 2 and the first anaerobic tank 3;

[0200] The exhaust volume of the first gas stripping device 41 is controlled by the first gas stripping gas control valve 42, thereby controlling the water volume lifted by the gas stripping device 41 and the dissolved oxygen content in the water, and also indirectly controlling the nitrification liquid reflux volume distributed to the first selection tank 1 through the first nitrification liquid reflux channel 17 at the end of the first aerobic tank B zone 7;

[0201] The second stripping device 51 in the first aerobic pool reflux stripping zone 5 uses the second stripping gas control valve 52 to control the exhaust volume of the second stripping device 51, thereby controlling the water volume lifted by the stripping device 51 and the dissolved oxygen content in the water, thereby controlling the reflux volume of the first aerobic pool B zone 7 from the end to the first aerobic pool A zone 6 through the first nitrification liquid reflux channel 17, and the reflux volume is adjustable by 15-30 times. The large proportion of nitrification liquid reflux dilutes the pollutant concentration in the first aerobic pool A zone 6, thereby reducing the inhibition of the reaction by high-concentration pollutants;

[0202] The fourth reflux control valve 63 is used to control the aerobic bacteria reflux pipe 20 to reflux the high-concentration aerobic bacteria flocs in the first-stage aerobic pool A zone 6, thereby increasing the degradation rate of organic matter in the first-stage aerobic pool A zone 6, ensuring that the COD concentration of the effluent after treatment in the first-stage aerobic pool A zone 6 is at a low value, thereby providing guarantee for the short-range nitrification reaction, short-range denitrification reaction and anaerobic ammonia oxidation reaction in the subsequent zones;

[0203] The aeration volume of the first aeration device 61 is controlled by the first aeration gas control valve 62, thereby controlling the dissolved oxygen concentration of the wastewater in the aerobic tank zone A 6, so as to facilitate the heterotrophic aerobic bacteria in the zone to fully perform the organic matter degradation reaction;

[0204] The second reflux control valve 73 controls the reflux amount of the sludge in the second-stage sedimentation tank 130 to flow back to the first-stage aerobic tank B zone 7 through the dominant bacteria return pipe 19, so as to maintain the high concentration of nitrite bacteria (AOB), short-range denitrifying bacteria, and anaerobic ammonia oxidizing bacteria in the first-stage aerobic tank B zone 7, thereby improving the removal rate of ammonia nitrogen and total nitrogen in the first-stage aerobic tank B zone 7;

[0205] Description: The pretreatment mechanism 991 used in the pretreatment stage of the treatment process of the present invention adopts an inverted A2 / O partitioning form, and mainly performs organic matter degradation, anaerobic phosphorus release, short-range nitrification, short-range denitrification and denitrification reactions, accompanied by certain anaerobic ammonia oxidation reactions. Most high-ammonia nitrogen wastewaters also have a relatively high organic matter content. Organic matter is an electron donor for heterotrophic bacteria, and when heterotrophic bacteria proliferate, they use organic matter as an electron donor and oxygen as an electron acceptor. Therefore, organic matter will cause the dominant growth of heterotrophic bacteria, competing with nitrite bacteria (AOB) for DO in the environment. Since the doubling time of heterotrophic bacteria is much shorter than that of autotrophic bacteria, rapidly proliferating heterotrophic bacteria can easily inhibit the growth of nitrite bacteria (AOB), destroy the short-range nitrification system, and prevent the nitrite nitrogen required for the anaerobic ammonia oxidation reaction from being well accumulated. The first stage of BM-AAO places the anoxic tank in front of the anaerobic tank, which is conducive to giving priority to meeting the carbon source requirements of denitrification and anaerobic phosphorus release, strengthening the system's demand for nitrogen removal and alkali production, and allowing all return sludge to undergo a complete anaerobic phosphorus release and aerobic phosphorus absorption process, which has a "group effect", improves the phosphorus removal capacity of the treatment system and reduces the oxygen demand for organic matter degradation;

[0206] When the organic matter in the wastewater is consumed in the BM-AAO first-stage anoxic tank 2, the first-stage anaerobic tank 3 and the first-stage aerobic tank A zone 6 to a C / N ratio of less than 0.7, the dissolved oxygen concentration of the aerobic tank in the first-stage aerobic tank B zone 7 is controlled at 0.5-0.7 mg / L and the pH is controlled at 7.5-8.0 to inhibit the growth of nitrite oxidizing bacteria, so that the ammonia nitrogen in the water only undergoes nitrosation reaction and further organic matter degradation reaction in the first-stage aerobic tank B zone 7, making nitrite-oxidizing bacteria (AOB) the dominant bacteria to achieve nitrite nitrogen enrichment.

[0207] The wastewater enriched with a large amount of nitrite nitrogen in the first aerobic tank B zone 7 enters the second selection tank 8, and the sludge in the second sedimentation tank 130 flows back to the second selection tank 8 through the dominant bacteria return pipe 19 and mixes with the wastewater in the second selection tank 8. The mixed wastewater passes through the second aerobic tank water inlet stripping zone 9 and then is transported to the second aerobic tank 110 by the third stripping device 91;

[0208] The wastewater in the second-stage aerobic tank 110 mainly undergoes short-range nitrification reaction, anaerobic ammonium oxidation reaction and partial organic matter degradation, and short-range denitrification reaction occurs inside the bacterial flocs;

[0209] After the wastewater passes through the second-stage aerobic tank 110 for anaerobic ammonia oxidation reaction, the wastewater with a certain amount of nitrate nitrogen is then fed into the second-stage anoxic tank 120;

[0210] The wastewater in the second stage anoxic tank 120 mainly undergoes short-range denitrification reaction, anaerobic ammonium oxidation reaction and partial denitrification reaction, reducing the nitrate nitrogen generated by the wastewater in the second stage aerobic tank 110 into nitrite nitrogen, and consuming a considerable portion of organic matter;

[0211] Then the wastewater in the second-stage anoxic tank 120 flows back to the second-stage aerobic tank return air stripping zone 100 through the anaerobic ammonium oxidation internal return channel 18. The wastewater in the second-stage aerobic tank return air stripping zone 100 is then transported to the second-stage aerobic tank 110 using the fourth air stripping device 101. On the one hand, the returned wastewater can dilute the wastewater entering the second-stage aerobic tank 11 for the first time to prevent the high concentration of organic matter, free ammonia and free nitrite from inhibiting the anaerobic ammonium oxidation reaction. On the other hand, it provides a reaction matrix for the anaerobic ammonium oxidation reaction, making full use of the anaerobic ammonium oxidation reaction to remove nitrogen in the water.

[0212] The wastewater from which nitrogen and most organic matter have been removed after being treated in the second-stage anoxic tank 120 enters the second-stage sedimentation tank 130, and the sludge in the wastewater in the second-stage sedimentation tank 130 is intercepted by the first solid-liquid separation and concentration device 131, and the sludge at the bottom of the second-stage sedimentation tank 130 is concentrated to a solid content of 20 g / L, effectively intercepting nitrite bacteria (AOB), anaerobic ammonia oxidizing bacteria (AnAOB), and short-range denitrifying bacteria in the mud-water mixture, and then the intercepted and concentrated dominant bacteria activated sludge is lifted to the dominant bacteria return pipe 19 by the fifth gas lift device 134 and then distributed to the first selection tank 1, the first aerobic tank B area 7 and the second selection tank 8, so as to maintain a high concentration of dominant bacteria activated sludge flora in the pretreatment stage and the main reaction stage, thereby ensuring the removal effect and denitrification rate of ammonia nitrogen and TN;

[0213] The first aeration and purging device 132 is used to regularly purge the first solid-liquid separation and concentration device 131 with air, so that air bubbles enter the first solid-liquid separation and concentration device 131 to violently disturb it, causing the sludge to fall from the device to the bottom of the second-stage sedimentation tank 130 to prevent the first solid-liquid separation and concentration device 131 from being blocked;

[0214] The third return control valve 83 is used to control the amount of sludge containing the dominant bacteria that flows back to the second-stage selection tank 8 through the dominant bacteria return pipe 19.

[0215] The fourth aeration and stirring gas control valve 82 is used to control the aeration amount of the fourth aeration and stirring device 81 to aerate the bottom of the second-stage selection tank 8 to prevent sludge from settling at the bottom of the second-stage selection tank 8;

[0216] The third stripping gas control valve 92 is used to control the exhaust volume of the third stripping device 91, thereby controlling the water volume lifted by the third stripping device 91 and the dissolved oxygen content in the water;

[0217] The fourth gas stripping gas control valve 102 is used to control the exhaust volume of the fourth gas stripping device 101, thereby controlling the lifting water volume of the fourth gas stripping device 101 and the dissolved oxygen content in the water;

[0218] The aeration amount of the fifth aeration agitator 111 is controlled by the fifth aeration agitator gas control valve 112 to prevent sludge from settling at the bottom of the second-stage aerobic tank 110 and to control the dissolved oxygen concentration in the second-stage aerobic tank 110 to be 0.5 mg / L;

[0219] Since the sludge in the second-stage sedimentation tank 130 has a high viscosity, the first solid-liquid separation and concentration device 131 plays a role in strengthening the sedimentation effect in the early stage of operation. A part of the intercepted sludge slides along the first solid-liquid separation and concentration device 131 to the bottom of the second-stage sedimentation tank 130 to continue to be concentrated, and another part of the activated sludge adheres to the first solid-liquid separation and concentration device 131 to form a biofilm. As the operation time goes by, the first solid-liquid separation and concentration device 131 gradually transforms into an upflow biofilter. In this process, the first solid-liquid separation and concentration device 131 has a good interception and removal of SS in the rising wastewater by adsorption and precipitation, and at the same time, it also performs biochemical reactions such as anaerobic ammonia oxidation and short-range denitrification to further purify the water quality;

[0220] Description: The main reaction mechanism 992 used in the main reaction stage of the treatment process of the present invention adopts the AO operation mode. The second-stage aerobic tank 110 controls the dissolved oxygen concentration at about 0.5 mg / L and the pH at 7.5-8.0, and mainly short-range nitrification and anaerobic ammonium oxidation reactions occur. The second-stage anoxic tank 120 controls the dissolved oxygen concentration at about 0.3-0.5 mg / L and the pH at 7.5-8.0, and mainly short-range denitrification and anaerobic ammonium oxidation reactions occur.

[0221] A solid-liquid separation and concentration device with a high solid load is arranged at the end of the main reaction mechanism 992, so that even if the activated sludge concentration of the influent of the second-stage sedimentation tank 130 at the end of the BM-AAO main reaction stage is as high as 10,000 mg / L, a good sludge retention effect can be obtained and the bottom sludge can be concentrated to a solid content of 12-20 g / L, and nitrite-oxidizing bacteria (AOB), anaerobic ammonia-oxidizing bacteria (AnAOB), and short-range denitrifying bacteria in the mud-water mixture can be effectively retained. The retained dominant bacteria are lifted and returned to the first selection tank 1, the first aerobic tank B zone 7, and the second selection tank 8 by the air lift device, so as to maintain a high concentration of dominant bacteria in the BM-AAO pretreatment stage and the main reaction stage, thereby ensuring the removal effect of ammonia nitrogen and TN. The wastewater treated in the second-stage sedimentation tank 130 first enters the third-stage aerobic tank water inlet stripping area 140, and the wastewater in the third-stage aerobic tank water inlet stripping area 140 is transported to the third-stage aerobic tank 150 by the sixth stripping device 141. Before being transported to the third-stage aerobic tank 150, the wastewater is mixed with the aerobic bacteria activated sludge retained in the third-stage sedimentation tank 160 and then enters the third-stage aerobic tank 150 together;

[0222] The dissolved oxygen concentration of the wastewater in the three-stage aerobic pool 150 is controlled to be 3 mg / L. The remaining organic matter in the wastewater is further fully degraded in the three-stage aerobic pool 150, and the remaining small amount of nitrite nitrogen of ammonia nitrogen is oxidized into nitrate nitrogen. At the same time, polyphosphate bacteria carry out a relatively sufficient aerobic phosphorus absorption reaction here, and the remaining TP is effectively absorbed by the biological reproduction and growth in the wastewater, which provides a strong guarantee for the control of organic matter, ammonia nitrogen, and TP in the final effluent;

[0223] The wastewater treated in the three-stage aerobic tank 150 enters the three-stage sedimentation tank 160, and the sludge in the wastewater of the three-stage sedimentation tank 160 is intercepted and concentrated by the second solid-liquid separation and concentration device 161, and the sludge at the bottom of the three-stage sedimentation tank 160 is concentrated to a solid content of 12-20g / L;

[0224] The effectively retained sludge contains nitrite bacteria (AOB), anaerobic ammonia oxidizing bacteria (AnAOB), short-range denitrifying bacteria and aerobic bacteria. The seventh gas lift device 164 is used to lift the retained and concentrated activated sludge to the aerobic bacteria return pipe 20 and then distribute it to the first aerobic tank A zone 6 and the third aerobic tank 150, so as to maintain a high aerobic bacteria concentration in the first aerobic tank A zone 6 and the third aerobic tank 150, thereby ensuring the removal effect of organic matter and the short-range denitrification rate;

[0225] A small portion of the anaerobic ammonia oxidizing bacteria and short-range denitrifying bacteria brought out of the second-stage sedimentation tank 130 are inhibited in the third-stage aerobic tank 150, but when the wastewater enters the third-stage sedimentation tank 160 from the third-stage aerobic tank 150, the activity of these bacteria will gradually recover;

[0226] The exhaust volume of the second aeration and purge device 162 is controlled by the second purge gas control valve 163, and the second aeration and purge device 162 is used to purge the second solid-liquid separation and concentration device 161 with air, so that bubbles enter the second solid-liquid separation and concentration device 161 to cause violent disturbance and cause the sludge to fall from the device to the bottom of the third-stage sedimentation tank 160, so as to prevent the second solid-liquid separation and concentration device 161 from being blocked;

[0227] The sixth gas stripping gas control valve 142 is used to control the exhaust volume of the sixth gas stripping device 141, thereby controlling the lifting water volume of the sixth gas stripping device 141 and the dissolved oxygen content in the water;

[0228] The aeration volume of the third aeration device 151 is controlled by the third aeration gas control valve 152 to control the dissolved oxygen of the wastewater in the three-stage aerobic tank 150 to be 3 mg / L;

[0229] The fifth reflux control valve 153 is used to control the amount of activated sludge refluxed from the aerobic bacteria reflux pipe 20 to the three-stage aerobic tank 150, so as to maintain the wastewater in the three-stage aerobic tank 150 with a high concentration of aerobic bacteria flocs, improve the degradation rate and nitrification rate of organic matter in the three-stage aerobic tank 150, and ensure that the organic matter, ammonia nitrogen, and TP in the final effluent meet the standards;

[0230] Since the sludge in the three-stage sedimentation tank 160 has a high viscosity, the second solid-liquid separation and concentration device 161 plays a role in strengthening the sedimentation effect in the early stage of operation. A part of the intercepted sludge slides along the second solid-liquid separation and concentration device 161 to the bottom of the three-stage sedimentation tank 160 to continue to concentrate, and another part of the activated sludge adheres to the second solid-liquid separation and concentration device 161 to form a biofilm. As the operation time goes by, the second solid-liquid separation and concentration device 161 gradually transforms into an upflow biological filter. In this process, the second solid-liquid separation and concentration device 161 has a good interception and removal of SS in the rising wastewater by adsorption and precipitation, and at the same time, it also carries out biochemical reactions such as anaerobic ammonia oxidation and short-range denitrification to further purify the water quality.

[0231] Description: The final stabilization treatment mechanism 993 used in the stable effluent stage of the treatment process of the present invention adopts the operation mode of the enhanced aerated aerobic tank to control the dissolved oxygen concentration at 2-3 mg / L, so that the remaining organic matter and organic nitrogen in the sewage can be fully degraded and oxidized, ensuring that the effluent organic matter and ammonia nitrogen meet the standards.

[0232] A solid-liquid separation and concentration device with a high solid load is set at the end of the stable effluent stage, so that even if the activated sludge concentration of the influent of the three-stage sedimentation tank 160 at the end of the stable effluent stage is as high as 10000 mg / L, a good sludge retention effect and a low effluent SS can be obtained. The trapped sludge is lifted by the air lift device, and a small part is discharged as residual sludge. Most of the activated sludge containing aerobic bacteria is returned to the first aerobic tank A zone 6 and the third aerobic tank 150 to maintain the concentration of aerobic bacteria for organic matter degradation in these two aerobic zones, thereby improving the reaction rate of the aerobic tank.

[0233] A large-flow circulating and reflux gas lift device is installed in front of each section of the aerobic pool, which can achieve 10-25 times of reflux and dilution of the aerobic pool. On the one hand, the entire biochemical system is in a completely mixed state like an oxidation ditch; on the other hand, the large-flow circulating and reflux gas lift device can greatly increase the water head of the aerobic pool in this section, which is conducive to ensuring the water head required for the operation of the subsequent section and allowing the nitrification liquid to flow back to each section of the anoxic pool by gravity; at the same time, each gas lift device is equivalent to a large jet aerator, which can effectively oxygenate the lifted sewage while completing the water lift to obtain a large-flow sewage circulation and water head lift, so as to reduce the aeration and oxygenation amount of the aerobic pool.

[0234] Since the bottom of the sedimentation zone of each section has a concentrating function, the sludge that falls to the bottom of the pool after interception can be concentrated to a solid content of 12-20g / L. Only 1-3 times of sludge return is needed to maintain the sludge concentration of each biochemical reaction pool at 6-10g / L, forming a high-microbial concentration operating condition similar to the MBR process, increasing the concentration of activated sludge in the biochemical pool, improving the rate of biodegradation, and reducing the amount of residual sludge generated.

[0235] The use of precise control technology enables the BM-AAO process to have the advantages of coupling the spatial denitrification of the traditional A2 / O process and the spatiotemporal denitrification of the SBR process. At the same time, it can also realize the coexistence of multiple processes in the same tank body (realizing the advantageous combination of nitrification, denitrification, short-range nitrification, short-range denitrification and anaerobic ammonia oxidation), which is conducive to the precise control of the pool capacity allocation, aeration time, oxygenation volume and stirring time of the anaerobic zone, anoxic zone, aerobic zone, anaerobic ammonia oxidation zone and other functional zones of the biochemical system according to the water inlet data of the biochemical system, so as to maximize the pool capacity of the anaerobic zone, anoxic zone and anaerobic ammonia oxidation zone, minimize the aeration tank capacity and aeration time, minimize the added carbon source and alkalinity, maximize the carbon source utilization rate, maximize the efficiency of denitrification and phosphorus removal and organic matter removal, and maximize the guarantee of stable compliance of effluent water quality. It helps sewage treatment plants to minimize energy and chemical consumption while enhancing their guarantee of stable compliance.

Claims

1. A process for treating high-ammonia nitrogen wastewater with low energy consumption and low carbon source addition, characterized in that: The following steps are involved: S1, pre-processing stage: S1-1, high concentration ammonia nitrogen wastewater first enters a first anoxic tank from a first selection tank for denitrification and short-range denitrification reaction; S1-2, the wastewater treated in step S1-1 enters an anaerobic tank, where polyphosphate-accumulating bacteria are used to rapidly degrade and absorb organic matter in the wastewater under anaerobic conditions; S1-3, the wastewater treated in step S1-2 enters the aerobic pool A for further degradation of organic matter, absorption of phosphorus under aerobic conditions and accumulation of nitrite nitrogen by short-range nitrification reaction; Control the C / N ratio of the treated wastewater in the aerobic tank A area to be less than 0.7; S1-4, the wastewater treated in step S1-3 enters zone B of the first aerobic pool to inhibit the growth of nitrite oxidizing bacteria, so that the ammonia nitrogen in the water only undergoes nitrite reaction and further organic matter degradation reaction in zone B of the first aerobic pool, and accumulates nitrite nitrogen, a substrate for anaerobic ammonia oxidation required for subsequent reactions; Control the dissolved oxygen concentration in the wastewater in the aerobic tank B to 0.5-0.7 mg / L and the pH to 7.5-8.0; S2, main reaction stage: S2-1, the wastewater treated in step S1-4 first enters the second-stage selection tank and then is transported to the second-stage aerobic tank, where the wastewater mainly undergoes short-range nitrification reaction, anaerobic ammonia oxidation reaction, partial short-range denitrification reaction and organic matter degradation; The dissolved oxygen concentration in the second-stage aerobic tank is controlled to be 0.4-0.6 mg / L and the pH is controlled to be 7.5-8.

0. In step S2-2, the dissolved oxygen concentration in the second-stage anoxic tank is controlled to be 0.3-0.5 mg / L and the pH is controlled to be 7.5-8.0; S2-2, the wastewater treated in step S2-1 enters the second-stage anoxic tank, where the wastewater mainly undergoes short-range denitrification reaction, anaerobic ammonium oxidation reaction and partial denitrification reaction; S2-3, the wastewater treated in step S2-2 enters the second-stage sedimentation tank, and the sludge at the bottom of the second-stage sedimentation tank is concentrated to a solid content of 12-20 g / L using a solid-liquid separation and concentration device; S3, stable water discharge stage: S3-1, the wastewater treated in step S2-3 enters the three-stage aerobic pool, the remaining organic matter in the wastewater is further degraded in the three-stage aerobic pool, the remaining small amount of ammonia nitrogen and nitrite nitrogen in the wastewater is oxidized into nitrate nitrogen, and the polyphosphate bacteria perform aerobic phosphorus absorption reaction in the three-stage aerobic pool; Control the dissolved oxygen concentration of wastewater in the three-stage aerobic tank to 2-3 mg / L; S3-2, the wastewater treated in step S3-1 enters the three-stage sedimentation tank, and the sludge at the bottom of the three-stage sedimentation tank is concentrated to a solid content of 12-20g / L using a solid-liquid separation and concentration device; The treated wastewater is discharged steadily from the three-stage sedimentation tank.

2. A process for treating high-ammonia nitrogen wastewater with low energy consumption and low carbon source addition according to claim 1, characterized in that: In step S1-1, the concentrated sludge intercepted by the second-stage sedimentation tank in step S2-3 and the nitrification liquid returned from the end of zone B of the first-stage aerobic tank in step S1-4 are returned to the first-stage selection tank and enter the first-stage anoxic tank together with the high-concentration ammonia nitrogen wastewater in the first-stage selection tank.

3. A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process according to claim 1, characterized in that: In step S2-1, the sludge intercepted and concentrated in the second-stage sedimentation tank in step S2-3 is returned to the second-stage selection tank and then enters the second-stage aerobic tank together with the wastewater in the second-stage selection tank.

4. A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process according to claim 1, characterized in that: In step S3-1, before the wastewater enters the three-stage aerobic tank, the concentrated sludge intercepted and concentrated in the three-stage sedimentation tank in step S3-2 is mixed with the wastewater and then enters the three-stage aerobic tank.

5. A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process according to claim 1, characterized in that: The first-stage selection tank, the first-stage anoxic tank, the first-stage anaerobic tank, the second-stage selection tank, the second-stage aerobic tank and the second-stage anoxic tank are all provided with an aeration agitator.

6. A low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment system, applied to a low-energy consumption, low-carbon source addition high-ammonia nitrogen wastewater treatment process as claimed in any one of claims 1 to 5, characterized in that: The system comprises a pre-processing mechanism (991), a main reaction mechanism (992) and a terminal stabilization processing mechanism (993); The pretreatment mechanism (991) comprises a selection tank (1), an anoxic tank (2), an anaerobic tank (3), an aerobic tank A zone (6), and an aerobic tank B zone (7) which are arranged in sequence; The first selection tank (1) is connected to the first anoxic tank (2), and the first anoxic tank (2) is connected to the first anaerobic tank (3); A nitrification liquid return channel (17) is provided between the aerobic tank B zone (7) and the selection tank (1); An aerobic tank inlet stripping zone (4) and an aerobic tank reflux stripping zone (5) are provided between the first anaerobic tank (3) and the first aerobic tank zone A (6); The first stage anaerobic pool (3) is connected to the input end of the first stage aerobic pool water inlet stripping zone (4), the output end of the first stage aerobic pool water inlet stripping zone (4) is connected to the first stage aerobic pool A zone (6), the output end of the first stage aerobic pool return stripping zone (5) is connected to the first stage aerobic pool A zone (6), and the input end of the first stage aerobic pool return stripping zone (5) is connected to the first stage nitrification liquid return channel (17); The first stage aerobic tank water inlet stripping zone (4) is provided with a first stripping device (41), and the gas supply pipe of the first stripping device (41) is provided with a first stripping gas control valve (42); the first stage aerobic tank reflux stripping zone (5) is provided with a second stripping device (51), and the gas supply pipe of the second stripping device (51) is provided with a second stripping gas control valve (52); A first aeration agitator (11) is provided at the bottom of the first stage selection tank (1), and a first aeration agitator (11) is provided on the air supply pipe thereof with a first aeration agitator gas control valve (12); a second aeration agitator (21) is provided at the bottom of the first stage anoxic tank (2), and a second aeration agitator (21) is provided on the air supply pipe thereof with a second aeration agitator gas control valve (22); a third aeration agitator (31) is provided at the bottom of the first stage anaerobic tank (3), and a third aeration agitator (31) is provided on the air supply pipe thereof with a third aeration agitator gas control valve (32); A first aeration device (61) is provided at the bottom of the aerobic tank section A (6), and a first aeration gas control valve (62) is provided on the air supply pipe of the first aeration device (61); a second aeration device (71) is provided at the bottom of the aerobic tank section B (7), and a second aeration gas control valve (72) is provided on the air supply pipe of the second aeration device (71); The main reaction mechanism (992) includes a second-stage selection tank (8), a second-stage aerobic tank (110), a second-stage anoxic tank (120), and a second-stage sedimentation tank (130) which are arranged in sequence; A fourth aeration agitator (81) is provided at the bottom of the second-stage selection tank (8), and a fourth aeration agitator gas control valve (82) is provided on the gas supply pipe of the fourth aeration agitator (81); The second-stage aerobic tank (110) is provided with a fifth aeration agitator (111), and the gas supply pipe of the fifth aeration agitator (111) is provided with a fifth aeration agitator gas control valve (112); The second-stage anoxic tank (120) is provided with a sixth aeration agitator (121), and the gas supply pipe of the sixth aeration agitator (121) is provided with a sixth aeration agitator gas control valve (122); The second-stage sedimentation tank (130) is provided with a first solid-liquid separation and concentration device (131) and a first aeration and purge device (132), and the gas supply pipe of the first aeration and purge device (132) is provided with a first purge gas control valve (133); The first aerobic tank B zone (7) is connected to the second selection tank (8), the second aerobic tank (110) is connected to the second anoxic tank (120), and the second anoxic tank (120) is connected to the second sedimentation tank (130); A second-stage aerobic tank water inlet stripping zone (9) and a second-stage aerobic tank reflux stripping zone (100) are provided between the second-stage selection tank (8) and the second-stage aerobic tank (110); The second-stage aerobic tank water inlet stripping zone (9) is provided with a third stripping device (91), and the gas supply pipe of the third stripping device (91) is provided with a third stripping gas control valve (92); the second-stage aerobic tank reflux stripping zone (100) is provided with a fourth stripping device (101), and the gas supply pipe of the fourth stripping device (101) is provided with a fourth stripping gas control valve (102); The second-stage selection tank (8) is connected to the input end of the second-stage aerobic tank water inlet stripping zone (9), the output end of the second-stage aerobic tank water inlet stripping zone (9) is connected to the second-stage aerobic tank (110), and the output end of the second-stage aerobic tank reflux stripping zone (100) is connected to the second-stage aerobic tank (110); The second-stage sedimentation tank (130) is provided with a fifth gas stripping device (134), the fifth gas stripping device (134) is respectively connected to the first-stage selection tank (1), the first-stage aerobic tank B zone (7) and the second-stage selection tank (8) through a dominant bacteria return pipe (19), and a fifth gas stripping gas control valve (135) is provided on the gas supply pipe of the fifth gas stripping device (134); The dominant bacteria return pipe (19) is located on the output pipes of the first-stage selection tank (1), the first-stage aerobic tank B zone (7) and the second-stage selection tank (8), and is respectively provided with a first return control valve (13), a second return control valve (73) and a third return control valve (83); An anaerobic ammonia oxidation internal reflow channel (18) is provided between the input end of the second-stage aerobic tank reflow stripping zone (100) and the second-stage anoxic tank (120); The final stage stabilization treatment mechanism (993) comprises a three-stage aerobic tank water inlet stripping zone (140), a three-stage aerobic tank (150), and a three-stage sedimentation tank (160) which are arranged in sequence; A second solid-liquid separation and concentration device (161) is provided in the three-stage sedimentation tank (160), a second aeration and purge device (162) is provided in the three-stage sedimentation tank (160), and a second purge gas control valve (163) is provided on the gas supply pipe of the second aeration and purge device (162); The three-stage aerobic pool (150) is provided with a third aeration device (151), and the air supply pipe of the third aeration device (151) is provided with a third aeration gas control valve (152); A sixth gas stripping device (141) is provided in the water inlet gas stripping zone (140) of the three-stage aerobic pool, and a sixth gas stripping gas control valve (142) is provided on the gas supply pipe of the sixth gas stripping device (141); The second-stage sedimentation tank (130) is connected to the input end of the water inlet stripping zone (140) of the three-stage aerobic tank, the output end of the water inlet stripping zone (140) of the three-stage aerobic tank is connected to the three-stage aerobic tank (150), and the three-stage aerobic tank (150) is connected to the three-stage sedimentation tank (160); The three-stage sedimentation tank (160) is provided with a seventh gas stripping device (164), the seventh gas stripping device (164) is respectively connected to the three-stage aerobic tank (150) and the first-stage aerobic tank A zone (6) through an aerobic bacteria return pipe (20), and the seventh gas stripping device (164) is provided with a seventh gas stripping gas control valve (165) on the gas supply pipe; The aerobic bacteria return pipe (20) is located in the first-stage aerobic pool A zone (6) and the output pipe of the third-stage aerobic pool (150) and has a fourth return control valve (63) and a fifth return control valve (153) respectively.

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