A device and method for realizing deep denitrification and dephosphorization by double short-range coupled anaerobic ammonia oxidation based on hydroxylamine addition

Abstract

A device and method for realizing deep denitrification and dephosphorization by double short-range coupled anaerobic ammonia oxidation based on hydroxylamine addition belong to the field of biological treatment of municipal domestic sewage. The device comprises a raw water tank, an AO reactor and an anoxic reactor. Domestic sewage first enters the AO reactor, releases phosphorus by anaerobic process, absorbs phosphorus by aerobic process, discharges residual sludge to realize efficient biological dephosphorization, and adds hydroxylamine to realize partial short-range nitrification coupled with anaerobic ammonia oxidation. Subsequently, the effluent containing ammonia nitrogen, nitrite and nitrate is mixed with domestic sewage in the anoxic reactor, and hydroxylamine is added again to realize short-range denitrification coupled with anaerobic ammonia oxidation for denitrification, while denitrification and phosphorus absorption reactions occur simultaneously. The present application utilizes the different inhibitory effects of hydroxylamine on nitrifying bacteria and the different enhancing effects of hydroxylamine on denitrifying bacteria, constructs a double short-range coupled anaerobic ammonia oxidation system, improves the efficiency of denitrification and dephosphorization, and saves the addition of external carbon source.

Description

TECHNICAL FIELD

[0001] The device and method for realizing deep denitrification and dephosphorization by double short-range coupling anaerobic ammonia oxidation based on hydroxylamine addition related to the application belong to the field of biological treatment of municipal sewage and are suitable for denitrification of municipal sewage with low carbon-nitrogen ratio. BACKGROUND

[0002] In recent years, excessive nitrogen and phosphorus emissions have led to increasingly serious water eutrophication. Biological denitrification and dephosphorization are highly concerned due to their advantages such as high economy and environmental friendliness, and they mainly remove nitrogen through nitrification and denitrification. Municipal sewage treatment plants have a huge treatment capacity and water quality varies greatly, so an efficient denitrification and dephosphorization process is needed. Traditional nitrification and denitrification produces a large amount of aeration energy consumption, consumes not-rich organic carbon sources and produces nitrous oxide gas. Anaerobic ammonia oxidation has the advantages of autotrophic denitrification, saving aeration energy consumption, low sludge yield and less greenhouse gas production, and is the most economical and efficient sewage denitrification technology to date.

[0003] A high and stable nitrite source is an important factor for realizing the anaerobic ammonia oxidation process. Hydroxylamine, as a key intermediate product of nitrification reaction, can improve the cell yield of ammonia-oxidizing bacteria (AOB) and inhibit the activity of nitrite-oxidizing bacteria (NOB) when added in an appropriate amount, thereby realizing stable short-range nitrification. In addition, the addition of hydroxylamine can also strengthen the nitrate reduction rate and nitrite reduction rate of denitrifying bacteria, and the strengthening effect on the former is more obvious, so that the intermediate nitrite in the denitrification process is effectively accumulated, thereby realizing short-range denitrification. The realization of short-range nitrification and short-range denitrification provides a stable substrate source for anaerobic ammonia-oxidizing bacteria, and the multi-path supply of nitrite guarantees the stability of the system. The realization of short-range nitrification can save 25% of the aeration amount, and the realization of short-range denitrification can save 40% of the organic carbon source. Combined with the advantages of autotrophic denitrification of anaerobic ammonia oxidation, deep denitrification of municipal sewage with low carbon-nitrogen ratio can be realized.

[0004] The method realizes the rapid start of short-range nitrification and short-range denitrification in two SBR reactors by adding hydroxylamine. After the two SBR reactors are stably operated in short-range, an anaerobic ammonia oxidation fixed bed filler is put into the reactors, and nitrogen and phosphorus in domestic sewage are simultaneously removed through short-range nitrification coupled with anaerobic ammonia oxidation reaction and short-range denitrification coupled with anaerobic ammonia oxidation reaction in the two reactors. The application effectively solves the problem of insufficient carbon source in municipal sewage and can save aeration energy consumption, and is an economical sewage denitrification and dephosphorization process with low energy consumption. SUMMARY

[0005] The application provides a device and method for realizing deep nitrogen and phosphorus removal by double short-range coupled anaerobic ammonia oxidation based on hydroxylamine addition, aiming at solving the problem of difficulty in obtaining nitrite for anaerobic ammonia oxidation.

[0006] The device for realizing deep nitrogen and phosphorus removal by double short-range coupled anaerobic ammonia oxidation based on hydroxylamine addition comprises a raw sewage tank (1), a short-range nitrification coupled anaerobic ammonia oxidation SBR (2), an intermediate tank (3) and a short-range denitrification coupled anaerobic ammonia oxidation SBR (4).

[0007] The short-range nitrification coupled anaerobic ammonia oxidation SBR (2) is provided with a first stirrer (2.2), an aeration disc (2.3), a gas flow meter (2.4), a first DO / pH tester (2.5), a first DO sensor (2.6), a first pH sensor (2.7), a first fixed filler frame (2.8), a first water inlet valve (2.9), a first water outlet valve (2.10) and a first sludge discharge valve (2.11).

[0008] The short-range denitrification coupled anaerobic ammonia oxidation SBR (4) is provided with a second stirrer (4.2), a second DO / pH tester (4.3), a second DO sensor (4.4), a second pH sensor (4.5), a second fixed filler frame (4.6), a second water inlet valve (4.7), a second water outlet valve (4.8) and a second sludge discharge valve (4.9).

[0009] Firstly, the raw sewage tank (1) is connected to the short-range nitrification coupled anaerobic ammonia oxidation SBR (2) through a first water inlet pump (2.1) and a first water inlet valve (2.9), the short-range nitrification coupled anaerobic ammonia oxidation SBR (2) is connected to the intermediate tank (3) through a first water outlet valve (2.10), the raw sewage tank (1) is connected to the intermediate tank (3) through a third water inlet pump (3.1), the intermediate tank (3) is connected to the short-range denitrification coupled anaerobic ammonia oxidation SBR (4) through a second water inlet pump (4.1) and a second water inlet valve (4.7), and finally, the effluent of the short-range denitrification coupled anaerobic ammonia oxidation SBR (4) is discharged through a second water outlet valve (4.8).

[0010] The application is realized by the following technical scheme.

[0011] 1) Start-up and operation of the short-range nitrification coupled anaerobic ammonia oxidation SBR: inoculation of a municipal sewage treatment plant A 2O Full-length sludge, sludge concentration of 2500-3000 mg / L. The sewage in the sewage raw water tank (1) enters the short-cut nitrification coupled anaerobic ammonia oxidation SBR reactor (2) through the water inlet pump. After the water inlet, the volume of the sludge-water mixture in the reactor is 85% of the effective volume of the SBR, the water inlet time is 10 min, after the water inlet, the stirrer (2.2) in the short-cut nitrification coupled anaerobic ammonia oxidation SBR reactor (2) is started, anaerobic stirring for 90 min, using the organic carbon source in the water to denitrify the nitrite nitrogen or nitrate nitrogen of the previous cycle, after anaerobic, a certain amount of hydroxylamine is added, so that the concentration of hydroxylamine in the short-cut nitrification coupled anaerobic ammonia oxidation SBR reactor (2) is 3.0-4.0 mg / L, added once a day, at the same time, the aeration is started, the aeration amount is adjusted by the gas flow meter (2.4) to make the dissolved oxygen concentration in the short-cut nitrification coupled anaerobic ammonia oxidation SBR be 0.5-1.0 mg / L, the aeration time is 90-180 min, after the aeration, the sludge is discharged through the first sludge discharge valve (2.11) every cycle to ensure the sludge age is 20-30 days, the stirrer (2.2) is closed, and the short-cut nitrification coupled anaerobic ammonia oxidation SBR reactor (2) is separated by static sinking for 60 min. The electric drainage valve (2.10) is opened, and the water is drained to the intermediate water tank (3), the drainage ratio is 50%, the drainage time is 10 min, and then the next cycle is carried out. After the nitrite accumulation rate in the effluent of the short-cut nitrification coupled anaerobic ammonia oxidation SBR reactor (2) reaches more than 70% and lasts for 7 days, the filler frame (2.8) containing the anaerobic ammonia oxidation fixed bed is placed in the short-cut nitrification coupled anaerobic ammonia oxidation SBR reactor (2), when the effluent COD is less than 30 mg / L, the effluent TIN is less than 15 mg / L, and the effluent PO4 3- <0.50 mg / L, it is proved that the short-cut nitrification coupled anaerobic ammonia oxidation SBR reactor (2) is successfully started.

[0012] 2) Start-up and operation of short-cut denitrification coupled anaerobic ammonia oxidation SBR: inoculated with municipal sewage treatment plant A 2O Full-length sludge, sludge concentration of 2500-3000 mg / L. The effluent of short-cut nitrification coupled with ANAMMOX SBR reactor (2) and equal volume of raw water enter the intermediate water tank (3). The wastewater in the intermediate water tank (3) enters the short-cut denitrification coupled with ANAMMOX SBR (4) through the water inlet pump. After water inlet, the volume of sludge-water mixture in the reactor is 85% of the effective volume of the SBR, and the water inlet time is 10 min. After water inlet, the agitator (4.2) in the short-cut denitrification coupled with ANAMMOX SBR reactor (4) is started, and a certain amount of hydroxylamine is added to make the concentration of hydroxylamine in the short-cut denitrification coupled with ANAMMOX SBR reactor (4) be 2.0-3.0 mg / L. The anoxic agitation is 4-6 h, the sludge age is ensured to be 20-30 days by discharging sludge every cycle through the second sludge discharge valve (4.9), the agitator (4.2) is turned off, and the sludge-water separation is achieved by static sedimentation for 60 min in the short-cut denitrification coupled with ANAMMOX SBR reactor (4). The electric drainage valve (4.8) is opened, the drainage ratio is 50%, the drainage time is 10 min, and then the next cycle is carried out. After the nitrite accumulation rate in the effluent of the short-cut denitrification coupled with ANAMMOX SBR reactor (4) reaches more than 80% and lasts for 7 days, the filler frame (4.6) containing the ANAMMOX fixed bed is placed in the short-cut denitrification coupled with ANAMMOX SBR reactor (4). When the COD in the effluent is less than 30 mg / L, the TIN in the effluent is less than 15 mg / L, and the PO43- 3- <0.50 mg / L, it is proved that the short-cut denitrification coupled with ANAMMOX SBR reactor (4) is successfully started.

[0013] 3) Device specific operation mode:

[0014] ① The municipal wastewater enters the short-cut nitrification coupled with ANAMMOX SBR reactor, the anaerobic agitation is 90 min, the aeration is 90-180 min, the dissolved oxygen concentration is controlled to be 0.5-1.0 mg / L, 3.0-4.0 mg / L concentration of hydroxylamine is added once a day, and the sludge age is 20-30 days. After the reaction is completed, 50% of the water is discharged into the intermediate water tank;

[0015] ② In the intermediate water tank, the effluent of the short-cut nitrification coupled with ANAMMOX SBR reactor and the raw water are mixed in equal volume, and then enter the short-cut denitrification coupled with ANAMMOX SBR. After anoxic agitation for 4-6 h, the precipitation is carried out for 30 min for drainage, the drainage ratio is 50%, 2.0-3.0 mg / L concentration of hydroxylamine is added once a day, and the sludge age is 20-30 days. After the reaction is completed, 50% of the water is discharged;

[0016] ③ The short-cut nitrification coupled with ANAMMOX SBR reactor and the short-cut denitrification coupled with ANAMMOX SBR reactor are alternately operated and repeatedly;

[0017] The application is a device and method for realizing deep denitrification and dephosphorization of double short-range coupled anaerobic ammonia oxidation based on hydroxylamine addition, and the technical principle is that 3.0-4.0 mg / L of hydroxylamine can improve the cell yield of ammonia oxidizing bacteria (AOB) and inhibit the activity of nitrite oxidizing bacteria (NOB), so as to realize stable short-range nitrification, in addition, 2.0-3.0 mg / L of hydroxylamine addition can improve the reduction rate of nitrate nitrogen and nitrite nitrogen, and the improvement of the former is more obvious, and the formation of short-range denitrification can be promoted by adding hydroxylamine. After the short-range effect is stable, anaerobic ammonia oxidation fixed bed filler is added, so as to realize short-range nitrification coupled with anaerobic ammonia oxidation and short-range denitrification coupled with anaerobic ammonia oxidation process respectively, and the urban domestic sewage is treated together, so as to realize efficient removal of nitrogen and phosphorus.

[0018] The application has the following advantages:

[0019] 1) The process adopts short-range nitrification, short-range denitrification coupled with anaerobic ammonia oxidation denitrification process, so that 25% of aeration energy consumption and 40% of organic carbon source can be saved;

[0020] 2) The reactor is an SBR reactor, which has the advantages of a sequencing batch reactor: simple process, flexible operation, large reaction driving force, good sedimentation and drainage effect, no sludge bulking, impact load resistance, and suitable for automatic operation;

[0021] 3) Hydroxylamine can quickly start the short-range nitrification and short-range denitrification process, and after about 7 days, the nitrite conversion rate can be greater than 70%;

[0022] 4) The multi-path nitrite supply mode provides guarantee for stable denitrification and dephosphorization of the reactor, and increases the system robustness. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a structure schematic view of the device of double short-range coupled anaerobic ammonia oxidation; as Figure 1 : 1 - raw water tank; 2 - short-range nitrification coupled with anaerobic ammonia oxidation SBR; 3 - intermediate water tank; 4 - short-range denitrification coupled with anaerobic ammonia oxidation SBR; 2.1 - first water inlet pump; 2.2 - first stirrer; 2.3 - aeration disc; 2.4 - gas flow meter; 2.5 - first DO / pH tester; 2.6 - first DO sensor; 2.7 - first pH sensor; 2.8 - first fixed filler rack; 2.9 - first water inlet valve; 2.10 - first water outlet valve; 2.11 - first sludge discharge valve; 4.1 - second water inlet pump; 4.2 - second stirrer; 4.3 - second DO / pH tester; 4.4 - second DO sensor; 4.5 - second pH sensor; 4.6 - second filler rack; 4.7 - second water inlet valve; 4.8 - second water outlet valve; 4.9 - second sludge discharge valve. DETAILED DESCRIPTION

[0024] The reactor used in the method is made of organic glass, and the effective volume of short-cut nitrification coupled with anaerobic ammonia oxidation SBR and short-cut denitrification coupled with anaerobic ammonia oxidation SBR is 10L. A stirrer is arranged in each SBR to ensure uniform mixing of sludge and water. Water is fed by a peristaltic pump, and water is discharged by a drain valve. The water inlet and outlet time is controlled by an online platform.

[0025] During the operation of the system, the sewage treatment process is as follows:

[0026] 1) First, the municipal sewage in the raw water tank (1) is fed into the short-cut nitrification coupled with anaerobic ammonia oxidation SBR reactor (2) through the first water inlet pump (2.1) and the first water inlet valve (2.9), anaerobic stirring, aerobic stirring, short-cut nitrification coupled with anaerobic ammonia oxidation reaction, opening the first sludge discharge valve (2.11) after aeration to discharge sludge, sedimentation after reaction, and water discharge from the short-cut nitrification coupled with anaerobic ammonia oxidation SBR reactor (2) into the intermediate water tank (3) through the first water discharge valve (2.10).

[0027] 2) After the effluent from the short-cut nitrification coupled with anaerobic ammonia oxidation SBR reactor (2) and an equal volume of raw water enter the intermediate water tank (3), the mixed sewage is fed into the short-cut denitrification coupled with anaerobic ammonia oxidation SBR (4) through the second water inlet pump (4.1) and the second water inlet valve (4.7), anoxic stirring, sedimentation, water discharge, and effluent from the short-cut denitrification coupled with anaerobic ammonia oxidation SBR reactor (4) is discharged through the second water discharge valve (4.9).

[0028] The specific operation parameters are as follows:

[0029] 1) Short-cut nitrification coupled with anaerobic ammonia oxidation SBR reactor: made of organic glass, effective volume 10L. The influent is domestic sewage, the water discharge ratio is 50%, and 5L of domestic sewage is fed per cycle. Influent 10min, anaerobic stirring 90min, aeration 90-180min, sedimentation 60min, water discharge 10min, and idle 20min. The inoculum sludge concentration is 2500-3000mg / L, and the sludge age is controlled at 20-30 days.

[0030] 2) Short-cut denitrification coupled with anaerobic ammonia oxidation SBR reactor: made of organic glass, effective volume 10L. The influent is an equal volume of short-cut nitrification coupled with anaerobic ammonia oxidation SBR reactor effluent and domestic sewage, the water discharge ratio is 50%, and 5L of mixed sewage is fed per cycle. Influent 10min, anoxic stirring 4-6h, sedimentation 60min, water discharge 10min, and idle 20min. The inoculum sludge concentration is 2500-3000mg / L, and the sludge age is controlled at 20-30 days.

[0031] 3) During the experimental operation, the short-cut nitrification coupled with ANAMMOX SBR reactor was dosed with 3.0-4.0 mg / L concentration of hydroxylamine, and the short-cut denitrification coupled with ANAMMOX SBR reactor was dosed with 2.0-3.0 mg / L concentration of hydroxylamine to maintain the short-cut nitrification and short-cut denitrification reaction.

[0032] 4) During the operation of the short-cut nitrification coupled with ANAMMOX SBR reactor, the dissolved oxygen in the reactor was controlled at 0.5-1.0 mg / L, and the dissolved oxygen in the short-cut denitrification coupled with ANAMMOX SBR reactor was controlled close to 0 mg / L, the temperature was room temperature, and the pH in the reactor was not deliberately controlled (the pH of raw water was between 7.2-7.8).

[0033] 5) During the experimental operation, the average COD, NH4 + -N, NO3 - -N, NO2 - -N, PO4 3- , and TIN concentrations of the effluent were as follows: 30 mg / L, 2.0 mg / L, 0.5 mg / L, 2.0 mg / L, 0.3 mg / L, and 4.5 mg / L, respectively. The above effluent indicators were stable and met the national first-level A standard.

Claims

1. A method for deep nitrogen and phosphorus removal based on hydroxylamine dosing and dual short-range coupled anaerobic ammonium oxidation, the apparatus used in this method comprising: Wastewater raw water tank (1), short-cut nitrification coupled with anaerobic ammonium oxidation SBR (2), intermediate water tank (3), short-cut denitrification coupled with anaerobic ammonium oxidation SBR (4); The short-range nitrification coupled anaerobic ammonium oxidation SBR (2) is equipped with a first stirrer (2.2), an aeration disc (2.3), a gas flow meter (2.4), a first DO / pH meter (2.5), a first DO sensor (2.6) and a first pH sensor (2.7), a first fixed packing frame (2.8), a first inlet valve (2.9), a first drain valve (2.10), and a first sludge discharge valve (2.11). The short-range denitrification coupled anaerobic ammonia oxidation SBR (4) is equipped with a second stirrer (4.2), a second DO / pH meter (4.3), a second DO sensor (4.4), a second pH sensor (4.5), a second fixed packing frame (4.6), a second inlet valve (4.7), a second drain valve (4.8), and a second sludge discharge valve (4.9). First, the raw wastewater tank (1) is connected to the short-cut nitrification coupled anaerobic ammonium oxidation SBR (2) through the first inlet pump (2.1) and the first inlet valve (2.9). The short-cut nitrification coupled anaerobic ammonium oxidation SBR (2) is connected to the intermediate tank (3) through the first drain valve (2.10). The raw wastewater tank (1) is connected to the intermediate tank (3) through the third inlet pump (3.1). The intermediate tank (3) is connected to the short-cut denitrification coupled anaerobic ammonium oxidation SBR (4) through the second inlet pump (4.1) and the second inlet valve (4.7). Finally, the effluent from the short-cut denitrification coupled anaerobic ammonium oxidation SBR (4) is discharged through the second drain valve (4.8). The method is characterized by comprising the following steps: Start-up and operation of short-cut nitrification coupled with anaerobic ammonium oxidation (SBR): Inoculation of municipal wastewater treatment plant A 2 The entire process produces sludge with a concentration of 2500-3000 mg / L. Wastewater from the raw wastewater tank (1) enters the short-cut nitrification coupled anaerobic ammonium oxidation (SBR) SBR (2) via the first influent pump. After influent, the volume of the sludge-water mixture in the reactor is 85% of the effective volume of the SBR. The influent time is 10 minutes. After influent, the first stirrer (2.2) in the short-cut nitrification coupled anaerobic ammonium oxidation (SBR) SBR (2) is turned on, and anaerobic stirring is performed for 90 minutes. The organic carbon source in the influent is used to denitrify the nitrite or nitrate nitrogen from the previous cycle. After anaerobic treatment, a certain amount of hydroxylamine is added to make the hydroxylamine concentration in the short-cut nitrification coupled anaerobic ammonium oxidation (SBR) SBR (2) 3.0-4.0 mg / L. This is done once a day, and aeration is simultaneously turned on. The aeration rate is adjusted by regulating the gas flow meter (2.4) to ensure the short-cut nitrification coupled anaerobic ammonium oxidation (SBR) SBR (2). The dissolved oxygen concentration inside is 0.5-1.0 mg / L, the aeration time is 90-180 min, after the aeration is completed, the sludge is discharged every cycle through the first sludge discharge valve (2.11) to ensure that the sludge age is 20-30 days, the first agitator (2.2) is closed, and the sludge is allowed to settle for 60 min to separate the sludge and water in the short-cut nitrification coupled anaerobic ammonium oxidation SBR (2); the first drain valve (2.10) is opened to drain the water into the intermediate water tank (3) with a drainage ratio of 50% and a drainage time of 10 min, and then the next cycle is carried out; after the nitrite accumulation rate in the effluent of the short-cut nitrification coupled anaerobic ammonium oxidation SBR (2) reaches more than 70% and lasts for 7 days, the first fixed packing frame (2.8) containing anaerobic ammonium oxidation bacteria is placed in the short-cut nitrification coupled anaerobic ammonium oxidation SBR (2). When the effluent COD < 30 mg / L, the effluent TIN < 15 mg / L, and the effluent PO4 < 30 mg / L, ... 3- When the concentration is <0.50 mg / L, it proves that the short-cut nitrification coupled anaerobic ammonium oxidation SBR(2) was successfully started; Start-up and operation of short-cut denitrification coupled with anaerobic ammonium oxidation (SBR): Inoculation of municipal wastewater treatment plant A 2 The entire process involves sludge, with a sludge concentration of 2500-3000 mg / L. The effluent from the short-cut nitrification coupled anaerobic ammonium oxidation (SBR) SBR (2) and an equal volume of raw water enter the intermediate water tank (3). Wastewater from the intermediate water tank (3) is pumped into the short-cut denitrification coupled anaerobic ammonium oxidation (SBR) SBR (4) via a second influent pump. After influent, the volume of the sludge-water mixture in the reactor is 85% of the effective volume of the SBR, and the influent time is 10 minutes. After influent, the second stirrer (4.2) in the short-cut denitrification coupled anaerobic ammonium oxidation (SBR) SBR (4) is turned on, and a certain amount of hydroxylamine is added to make the hydroxylamine concentration in the short-cut denitrification coupled anaerobic ammonium oxidation (SBR) SBR (4) 2.0-3.0 mg / L. Anoxic stirring is performed for 4-6 minutes. h, the sludge age is maintained at 20-30 days per cycle by discharging sludge through the second sludge discharge valve (4.9), the second agitator (4.2) is closed, and the sludge is allowed to settle for 60 minutes to separate the sludge and water in the short-cut denitrification coupled anaerobic ammonium oxidation SBR (4); the second drain valve (4.8) is opened, the drainage ratio is 50%, and the drainage time is 10 minutes, and then the next cycle is carried out; after the nitrite accumulation rate in the effluent of the short-cut denitrification coupled anaerobic ammonium oxidation SBR (4) reaches more than 80% and continues for 7 days, the second fixed packing frame (4.6) containing anaerobic ammonium oxidation bacteria is placed in the short-cut denitrification coupled anaerobic ammonium oxidation SBR (4). When the effluent COD < 30 mg / L, the effluent TIN < 15 mg / L, and the effluent PO4 < 30 mg / L, ... 3- When the concentration is <0.50 mg / L, it proves that the short-cut denitrification coupled anaerobic ammonia oxidation SBR (4) was successfully started; 3) Specific operating modes of the device: ① Urban sewage from the raw wastewater tank enters the short-cut nitrification coupled anaerobic ammonium oxidation (SBR) process. Anaerobic stirring is performed for 90 minutes, followed by aeration for 90-180 minutes. The dissolved oxygen concentration is controlled at 0.5-1.0 mg / L. Hydroxylamine at a concentration of 3.0-4.0 mg / L is added once a day. The sludge age is 20-30 days. After the reaction is completed, 50% of the water is discharged into the intermediate water tank. ② In the intermediate tank, the effluent and raw water of the short-cut nitrification coupled anaerobic ammonium oxidation SBR are mixed in equal volumes, and then the mixture enters the short-cut denitrification coupled anaerobic ammonium oxidation SBR. After 4-6 hours of anoxic stirring, the mixture is allowed to settle for 30 minutes before being drained. The drainage ratio is 50%. Hydroxylamine at a concentration of 2.0-3.0 mg / L is added once a day, and the sludge age is 20-30 days. After the reaction is completed, 50% of the water is discharged. ③ The short-cut nitrification coupled with anaerobic ammonium oxidation (SBR) and the short-cut denitrification coupled with anaerobic ammonium oxidation (SBR) are operated alternately and repeatedly.

Images