1. Device that sewage denitrogenation and mud decrement are realized to normal position sludge hydrolysis acidification coupling short distance denitrification anaerobic ammonium oxidation integration, its characterized in that includes: a sewage inlet water tank (1), a full-process nitrification SBR reactor (2), a nitrification liquid intermediate water tank (3), a sludge mixed liquid storage tank (4), a hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) and an outlet water tank (6);

the full-process nitrification SBR reactor (2) comprises a first peristaltic pump (2.1), a first water inlet (2.2), a stirring device (2.3), a pH/DO online monitor (2.4), a first water outlet (2.5), a gas flowmeter (2.6), an aeration disc (2.7) and an aeration pump (2.8); the sludge mixed liquid storage tank (4) comprises a magnetic stirrer (4.1); the hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated denitrification reactor (5) comprises a second peristaltic pump (5.1), a second water inlet (5.2), a third peristaltic pump (5.3), a third water inlet (5.4), a fourth peristaltic pump (5.5), a fourth water inlet (5.6), a stirring device (5.7), a pH/ORP on-line monitor (5.8), a heating rod (5.9) and a second water outlet (5.10);

ammonia nitrogen wastewater in the sewage inlet water tank (1) is pumped into the full-process nitrification SBR reactor (2) from a first water inlet (2.2) through a first peristaltic pump (2.1), and effluent is discharged into a nitrification liquid intermediate water tank (3) through a first water outlet; before entering the second sequencing batch SBR, sludge in the sludge mixed liquid storage tank (4) is uniformly stirred by a magnetic stirrer (4.1) in advance, then is pumped into a hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a second water inlet (5.2) by a second peristaltic pump (5.1), sewage in a water inlet tank is pumped into the hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a third water inlet (5.4) by a third peristaltic pump (5.3), sewage in a nitrified liquid intermediate water tank is pumped into the hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a fourth water inlet (5.6) by a fourth peristaltic pump (5.5), and effluent is discharged into an effluent water tank by a second water outlet.

2. Method for applying the device according to claim 1, comprising the steps of:

(1) starting the system:

(1.1) starting the full-range nitration SBR reactor: inoculating sludge to be residual sludge in a secondary sedimentation tank of an urban sewage treatment plant, keeping the sludge concentration in a full-course nitrification SBR reactor at 2000-4000mg/L, and keeping the water inlet to be domestic sewage, wherein the water quality condition is that the ammonia nitrogen concentration is 60-80mg/L, the nitrite nitrogen concentration is 0-0.5mg/L, the nitrate nitrogen concentration is 0-0.5mg/L, the COD concentration is 160-310mg/L, and the C/N ratio is 2-4; the method runs for 2 periods every day, each period is 8 hours, and the method comprises five processes of water inlet, aeration, sedimentation, water drainage and idling; in each period, domestic sewage is pumped into a full-process nitrification SBR reactor (2) by a first water inlet pump (2.1), after water inlet is finished, a stirring and aeration device is started at the same time, the dissolved oxygen concentration in the reactor is controlled to be 1-3mg/L through a DO online monitor (2.4) and a gas flowmeter (2.6), aerobic aeration is carried out for 4-6h, stirring is stopped when aeration is finished, precipitation is carried out for 40-70min, the water drainage ratio is 40-60%, the idle time is 80-120min, and after idle, the domestic sewage enters the next period; when more than 95% of ammonia nitrogen is converted into nitrate nitrogen and stably runs, the nitration SBR reactor is considered to be successfully started;

(1.2) starting the hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated denitrification reactor: the inoculated sludge is primary sludge and anaerobic ammonium oxidation sludge of an urban sewage treatment plant, the mass ratio of the inoculated primary sludge to the anaerobic ammonium oxidation sludge is 3-5: 1, and the sludge concentration in the SBR reactor is kept at 3500-5000 mg/L;

determining the input of organic matters, nitrifying liquid and raw water in a hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated reactor (5) according to a calculation formula (I) and (II):

V1+V2+V3＝V*P ③

in the formula:

C_SCODthe concentration of SCOD under the maximum fermentation potential of the excess sludge;

C_NO3 ^-is the concentration of nitrate nitrogen in the influent water;

C_NH4 ⁺the ammonia nitrogen concentration of the inlet water;

v1, V2, V3 and V are respectively the residual sludge intake, the nitrification liquid wastewater intake, the raw water intake and the effective volume of the reactor;

the C/N ratio is a set value of the mass concentration ratio of the influent SCOD to the nitrate nitrogen and is set to be 3-6: 1;

NO₃ ^-/NH₄ ⁺the ratio is a set value of the mass concentration ratio of the nitrate nitrogen to the ammonia nitrogen and is set to be 1-1.2: 1;

p is a water discharge ratio and is set to be 60%;

the success of starting the total nitrogen of the effluent is lower than 5 mg/L;

(2) the operation of the system is as follows:

(2.1) operation of the full-range nitration SBR reactor: in each period, sewage in the domestic sewage inlet water tank (1) enters the sequencing batch SBR reactor through a first water inlet pump (2.1), a stirring and aeration device is started after water inlet is finished, dissolved oxygen in the reactor is controlled to be kept at 1-3mg/L through a gas flowmeter (2.6), aerobic aeration is carried out for 4-6h, the sludge age is controlled to be 8-15 days, the sludge concentration is controlled to be 2000-4000mg/L, stirring is closed when aeration is finished, sedimentation is carried out for 40-70min, the water drainage ratio is 40-60%, the idle time is 80-120min, effluent enters a nitrifying liquid intermediate water tank, and the next period is carried out after the period is finished;

(2.2) operation of the hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated SBR reactor: sludge in the sludge mixed liquid storage tank (4) is uniformly stirred by a magnetic stirrer (4.1) for one hour in advance and then enters Sequencing Batch Reactor (SBR) through a second water inlet pump (5.2), and anaerobic stirring is carried out for 6-8 hours in each period, so that stirring is finished when the hydrolysis acidification rate reaches 80-95%; and starting a third water inlet pump (5.3) and a fourth water inlet pump (5.5) to pump the sewage in the sewage inlet water tank (1) and the nitrifying liquid intermediate water tank (3) into the Sequencing Batch Reactor (SBR) so that the mass concentration ratio of nitrate nitrogen to ammonia nitrogen in the sewage inlet water tank and the nitrifying liquid intermediate water tank meets a set value of 1-1.2: 1, carrying out anoxic stirring for 3 hours to perform short-range denitrification coupling anaerobic ammonia oxidation reaction, settling for 10 minutes after stopping stirring, draining, and allowing to stand for the next period.

Background

With the rapid development of social economy and the improvement of the living standard of people, the problem of water environment pollution gradually draws attention of people. The problem of water eutrophication caused by excessive nitrogen and phosphorus is not solved well and is becoming serious day by day. Biological denitrification is the only effective method for treating domestic sewage so far.

The anaerobic ammonia oxidation process is a process for converting ammonia nitrogen into nitrogen by taking nitrite nitrogen as an electron acceptor under anaerobic conditions, and an organic carbon source and O are not required in the reaction process₂The intervention of (1). From the engineering perspective, the anaerobic ammonia oxidation process has obvious advantages compared with the traditional biological denitrification process, the process can get rid of the constraint of the traditional electron donor (organic carbon source), and the oxygen demand in the nitrification process can be saved, so that the residual sludge is reduced, and the energy is saved.

The short-cut denitrification is used as one of nitrite nitrogen sources, which means that denitrifying bacteria convert nitrate nitrogen into nitrite nitrogen by using organic matters, and compared with the condition that the short-cut nitrification is easily damaged, the short-cut denitrification has the advantage of being more stable. The combination of short-cut denitrification and anaerobic ammonia oxidation has wider prospect for sewage denitrification.

Each large sewage treatment plant discharges a large amount of excess sludge every day, which, if not properly treated, also causes another form of environmental pollution. The carbon source in the domestic sewage is not enough to meet the utilization of short-range denitrification, the carbon source such as sodium acetate is commonly utilized in the current research, and the residual sludge is another carbon source in a complex form, so that the complex organic matters in the sludge can be converted into the easily degradable carbon source for use through hydrolytic acidification.

Therefore, the hydrolytic acidification of the sludge and the short-cut denitrification anaerobic ammonia oxidation are combined, so that the problem of insufficient carbon source in raw water can be solved, the sludge reduction can be realized, and the denitrification, energy conservation and consumption reduction of an urban sewage treatment plant can be realized.

Disclosure of Invention

The invention provides a device and a method for realizing domestic sewage denitrification and sludge reduction by integrating in-situ sludge hydrolysis acidification and short-cut denitrification anaerobic ammonia oxidation. Firstly, domestic sewage enters a full-course nitrification reactor for nitrification reaction, and ammonia nitrogen in the sewage is completely converted into nitrate nitrogen under the action of nitrifying bacteria; secondly, the residual sludge in the sludge mixed liquid storage tank enters a second reactor for hydrolysis acidification, and macromolecular slowly-degradable organic matters in the sludge mixed liquid storage tank are hydrolyzed and acidified into micromolecular easily-degradable organic matters for subsequent short-cut denitrification; then the effluent of the nitration reactor and the domestic sewage enter the reactor together through a water inlet pump to generate a short-cut denitrification anaerobic ammonia oxidation reaction so as to remove the total nitrogen. The invention is suitable for the domestic sewage with low carbon-nitrogen ratio, solves the problem that the organic matters in the domestic sewage are not enough for short-range denitrification utilization by utilizing the easily degradable organic matters generated by hydrolysis and acidification of the sludge, simultaneously realizes sludge reduction and achieves the purposes of energy saving and consumption reduction.

The purpose of the invention is solved by the following technical scheme: the device and the method for realizing domestic sewage denitrification and sludge reduction by integrating in-situ sludge hydrolysis acidification and short-cut denitrification anaerobic ammonia oxidation are characterized in that:

the device comprises: a domestic sewage inlet water tank (1), a full-process nitrification SBR reactor (2), a nitrification liquid intermediate water tank (3), a sludge mixed liquid storage tank (4), a hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) and an outlet water tank (6);

the full-process nitrification SBR reactor (2) comprises a first peristaltic pump (2.1), a first water inlet (2.2), a stirring device (2.3), a pH/DO online monitor (2.4), a first water outlet (2.5), a gas flowmeter (2.6), an aeration disc (2.7) and an aeration pump (2.8); the sludge mixed liquid storage tank (4) comprises a magnetic stirrer (4.1); the hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated denitrification reactor (5) comprises a second peristaltic pump (5.1), a second water inlet (5.2), a third peristaltic pump (5.3), a third water inlet (5.4), a fourth peristaltic pump (5.5), a fourth water inlet (5.6), a stirring device (5.7), a pH/ORP on-line monitor (5.8), a heating rod (5.9) and a second water outlet (5.10);

ammonia nitrogen wastewater in the domestic sewage inlet water tank (1) is pumped into the full-process nitrification SBR reactor (2) from a first water inlet (2.2) through a first peristaltic pump (2.1), and effluent is discharged into a nitrified liquid intermediate water tank (3) through a first water outlet; before entering the second sequencing batch SBR, sludge in the sludge mixed liquid storage tank (4) is uniformly stirred by a magnetic stirrer (4.1) in advance, then is pumped into a hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a second water inlet (5.2) by a second peristaltic pump (5.1), sewage in the domestic sewage water inlet tank is pumped into the hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a third water inlet (5.4) by a third peristaltic pump (5.3), sewage in the nitrified liquid intermediate tank is pumped into the hydrolysis acidification coupling denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a fourth water inlet (5.6) by a fourth peristaltic pump (5.5), and effluent is discharged into an effluent water tank by a second water outlet.

2. The method for applying the device is characterized by comprising the following steps:

(1) starting the system:

(1.1) starting the full-range nitration SBR reactor: inoculating sludge to be residual sludge in a secondary sedimentation tank of an urban sewage treatment plant, keeping the sludge concentration in a full-course nitrification SBR reactor at 2000-4000mg/L, and keeping the water inlet to be domestic sewage, wherein the water quality condition is that the ammonia nitrogen concentration is 60-80mg/L, the nitrite nitrogen concentration is 0-0.5mg/L, the nitrate nitrogen concentration is 0-0.5mg/L, the COD concentration is 160-310mg/L, and the C/N ratio is 2-4; the method runs for 2 periods every day, each period is 8 hours, and the method comprises five processes of water feeding, aeration, sedimentation, water drainage and idling. In each period: domestic sewage is pumped into the full-process nitrification SBR reactor (2) by a first water inlet pump (2.1), after water inlet is finished, a stirring and aeration device is started at the same time, the dissolved oxygen concentration in the reactor is controlled to be 1-3mg/L through a DO online monitor (2.4) and a gas flowmeter (2.6), aerobic aeration is carried out for 4-6h, stirring is closed when aeration is finished, precipitation is carried out for 40-70min, the drainage ratio is 40-60%, the idle time is 80-120min, and the sewage enters the next period after the idle. When more than 95 percent of ammonia nitrogen is converted into nitrate nitrogen and stably runs, the nitration SBR reactor is considered to be successfully started.

(1.2) starting the hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated denitrification reactor: the inoculated sludge is primary sludge and anaerobic ammonium oxidation sludge of an urban sewage treatment plant, the mass ratio of the inoculated primary sludge to the anaerobic ammonium oxidation sludge is 3-5: 1, and the sludge concentration in the SBR reactor is kept at 3500-5000 mg/L.

Taking the residual sludge to carry out hydrolytic acidification at 30 ℃, and determining the concentration of SCOD (small fluctuation within plus or minus 5%) in 20 minutes to determine that the concentration is the maximum potential of the sludge hydrolytic acidification at the concentration;

determining the input of organic matters, nitrifying liquid and raw water in a hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated reactor (5) according to a calculation formula (I) and (II):

V1+V2+V3＝V*P ③

in the formula:

C_SCODthe concentration of SCOD under the maximum fermentation potential of the excess sludge;

C_NO3 ^-is the concentration of nitrate nitrogen in the influent water;

C_NH4 ⁺the ammonia nitrogen concentration of the inlet water;

v1, V2, V3 and V are respectively the residual sludge intake, the nitrification liquid wastewater intake, the raw water intake and the effective volume of the reactor;

the C/N ratio is a set value of the mass concentration ratio of the influent SCOD to the nitrate nitrogen and is set to be 3-6: 1;

NO₃ ^-/NH₄ ⁺the ratio is a set value of the mass concentration ratio of the nitrate nitrogen to the ammonia nitrogen and is set to be 1-1.2: 1;

p is a water discharge ratio and is set to be 60%;

the system effluent total nitrogen below 5mg/L was considered successful in start-up.

(2) The operation of the system is as follows:

(2.1) operation of the full-range nitration SBR reactor: in each period, sewage in the domestic sewage inlet water tank (1) enters the sequencing batch SBR reactor through a first water inlet pump (2.1), a stirring and aeration device is started after water inlet is finished, dissolved oxygen in the reactor is controlled to be kept at 1-3mg/L through a gas flowmeter (2.6), aerobic aeration is carried out for 4-6h, the sludge age is controlled to be 8-15 days, the sludge concentration is controlled to be 2000-4000mg/L, stirring is closed when aeration is finished, sedimentation is carried out for 40-70min, the water drainage ratio is 40-60%, the idle time is 80-120min, effluent enters a nitrifying liquid intermediate water tank, and the next period is carried out after the period is finished;

(2.2) operation of the hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated SBR reactor: sludge in the sludge mixed liquid storage tank (4) is uniformly stirred by a magnetic stirrer (4.1) for one hour in advance and then enters Sequencing Batch Reactor (SBR) through a second water inlet pump (5.2), and anaerobic stirring is carried out for 6-8 hours in each period, so that stirring is finished when the hydrolysis acidification rate reaches 80-95%; and (3) starting a third water inlet pump (5.3) and a fourth water inlet pump (5.5) to pump the sewage in the domestic sewage inlet water tank (1) and the nitrifying liquid intermediate water tank (3) into the Sequencing Batch Reactor (SBR), enabling the mass concentration ratio of nitrate nitrogen to ammonia nitrogen to meet a set value of 1-1.2: 1, carrying out anoxic stirring for 3 hours to carry out short-range denitrification coupling anaerobic ammonia oxidation reaction, settling for 10 minutes after stopping stirring, draining water, standing, and entering the next period.

The invention has the following advantages:

1) compared with the traditional biological denitrification process for treating the urban domestic sewage with the low C/N ratio, the method can save 100 percent of external carbon source investment after formal operation.

2) By utilizing hydrolytic acidification of the sludge, sludge reduction can be realized while a carbon source is provided for short-cut denitrification, and the treatment cost of the excess sludge can be saved.

3) The organic matter produced by hydrolytic acidification can be utilized by denitrifying bacteria in situ, and the nitrite produced by short-range denitrification can be utilized by anaerobic ammonium oxidation bacteria in time while being produced, thereby avoiding the toxic action of high nitrite nitrogen on microorganisms.

4) Through domestication, the harmonious coexistence of the three strains of the hydrolytic acidification bacteria, the short-range denitrifying bacteria and the anaerobic ammonium oxidation bacteria can be realized.

Drawings

FIG. 1 is a schematic diagram of: the device and the method for realizing domestic sewage denitrification and sludge reduction by integrating in-situ sludge hydrolysis acidification and short-cut denitrification anaerobic ammonia oxidation.

In fig. 1: 1-a domestic sewage inlet water tank, 2-a full-course nitrification SBR reactor, 3-a nitrification liquid intermediate water tank, 4-a sludge mixed liquid storage tank, 5-a hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor, and 6-an outlet water tank; 2.1-a first peristaltic pump, 2.2-a first water inlet, 2.3-a stirring device, 2.4-a pH/DO online monitor, 2.5-a first water outlet, 2.6-a gas flowmeter, 2.7-an aeration disc and 2.8-an aeration pump; 4.1-magnetic stirrer; 5.1-second peristaltic pump; 5.2-a second water inlet, 5.3-a third peristaltic pump, 5.4-a third water inlet, 5.5-a fourth peristaltic pump, 5.6-a fourth water inlet, 5.7-a stirring device, 5.8-a pH/DO online monitor, 5.9-a heating rod, and 5.10-a second water outlet.

Detailed Description

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and examples:

as shown in fig. 1, the device and the method for realizing domestic sewage denitrification and sludge reduction by integrating in-situ sludge hydrolysis acidification and short-cut denitrification anaerobic ammonia oxidation, the device comprises: a domestic sewage inlet water tank (1), a full-process nitrification SBR reactor (2), a nitrification liquid intermediate water tank (3), a sludge mixed liquid storage tank (4), a hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) and an outlet water tank (6); the method is characterized in that ammonia nitrogen wastewater in the domestic sewage inlet water tank (1) is pumped into a full-process nitrification SBR reactor (2) from a first water inlet (2.2) through a first peristaltic pump (2.1), and effluent is discharged into a nitrified liquid intermediate water tank (3) through a first water outlet; before entering the second sequencing batch SBR, sludge in the sludge mixed liquid storage tank (4) is uniformly stirred by a magnetic stirrer (4.1) in advance, then is pumped into a hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a second water inlet (5.2) by a second peristaltic pump (5.1), sewage in the domestic sewage water inlet tank is pumped into the hydrolysis acidification coupling short-range denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a third water inlet (5.4) by a third peristaltic pump (5.3), sewage in the nitrified liquid intermediate tank is pumped into the hydrolysis acidification coupling denitrification and anaerobic ammonia oxidation integrated denitrification reactor (5) from a fourth water inlet (5.6) by a fourth peristaltic pump (5.5), and effluent is discharged into an effluent water tank by a second water outlet.

The experimental system is shown in figure 1, each reactor is made of organic glass, the total volume of the whole nitration SBR reactor (2) is 11L, and the effective volume is 10L; 11L of hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated denitrification reactor (5) and 10L of effective volume.

In the test process, the specific experimental water is taken from domestic sewage discharged by Beijing university of industry, and the specific water quality is as follows: the COD concentration is 160-310mg/L, the ammonia nitrogen concentration is 60-80mg/L, the nitrite nitrogen concentration is 0-0.5mg/L, and the nitrate nitrogen concentration is 0-0.5 mg/L.

The specific operation is as follows:

(1) starting the system:

(1.1) starting the full-range nitration SBR reactor: inoculating sludge to be residual sludge in a secondary sedimentation tank of an urban sewage treatment plant, keeping the sludge concentration in a full-course nitrification SBR reactor at 2000-4000mg/L, and keeping the water inlet to be domestic sewage, wherein the water quality condition is that the ammonia nitrogen concentration is 60-80mg/L, the nitrite nitrogen concentration is 0-0.5mg/L, the nitrate nitrogen concentration is 0-0.5mg/L, the COD concentration is 160-310mg/L, and the C/N ratio is 2-4; the method runs for 2 periods every day, each period is 8 hours, and the method comprises five processes of water feeding, aeration, sedimentation, water drainage and idling. Before the beginning of each period: domestic sewage is pumped into the full-process nitrification SBR reactor (2) by a first water inlet pump (2.1), after water inlet is finished, a stirring and aeration device is started at the same time, the dissolved oxygen concentration in the reactor is controlled to be 1-3mg/L through a DO online monitor (2.4) and a gas flowmeter (2.6), aerobic aeration is carried out for 4-6h, stirring is closed when aeration is finished, precipitation is carried out for 40-70min, the drainage ratio is 40-60%, the idle time is 80-120min, and the sewage enters the next period after the idle. When more than 95 percent of ammonia nitrogen is converted into nitrate nitrogen and stably runs, the nitration SBR reactor is considered to be successfully started.

(1.2) starting the hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated denitrification reactor: the inoculated sludge is primary sludge and anaerobic ammonium oxidation sludge of an urban sewage treatment plant, the mass ratio of the inoculated primary sludge to the anaerobic ammonium oxidation sludge is 3-5: 1, and the sludge concentration in the SBR reactor is kept at 3500-5000 mg/L.

Taking the residual sludge to carry out hydrolytic acidification at 30 ℃, and determining the concentration of SCOD (cyclic activated sludge OD), wherein when the concentration of SCOD has no growth trend and small fluctuation within 20 minutes, the concentration is determined to be the maximum potential of the hydrolytic acidification of the sludge at the concentration;

determining the input of organic matters, nitrifying liquid and raw water in a hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated reactor (5) according to a calculation formula (I) and (II):

V1+V2+V3＝V*P ③

in the formula:

C_SCODthe concentration of SCOD under the maximum fermentation potential of the excess sludge;

C_NO3 ^-is the concentration of nitrate nitrogen in the influent water;

C_NH4 ⁺the ammonia nitrogen concentration of the inlet water;

v1, V2, V3 and V are respectively the residual sludge intake, the nitrification liquid wastewater intake, the raw water intake and the effective volume of the reactor;

the C/N ratio is a set value of the mass concentration ratio of the influent SCOD to the nitrate nitrogen and is set to be 3-6: 1;

NO₃ ^-/NH₄ ⁺the ratio is a set value of the mass concentration ratio of the nitrate nitrogen to the ammonia nitrogen and is set to be 1-1.2: 1;

p is a water discharge ratio and is set to be 60%;

the system effluent total nitrogen below 5mg/L was considered successful in start-up.

(2) The operation of the system is as follows:

(2.1) operation of the full-range nitration SBR reactor: in each period, sewage in the domestic sewage inlet water tank (1) enters the sequencing batch SBR reactor through a first water inlet pump (2.1), a stirring and aeration device is started after water inlet is finished, dissolved oxygen in the reactor is controlled to be kept at 1-3mg/L through a gas flowmeter (2.6), aerobic aeration is carried out for 4-6h, the sludge age is controlled to be 8-15 days, the sludge concentration is controlled to be 2000-4000mg/L, stirring is closed when aeration is finished, sedimentation is carried out for 40-70min, the water drainage ratio is 40-60%, the idle time is 80-120min, effluent enters a nitrifying liquid intermediate water tank, and the next period is carried out after the period is finished;

(2.2) operation of the hydrolysis acidification coupling short-cut denitrification anaerobic ammonia oxidation integrated SBR reactor: sludge in the sludge mixed liquid storage tank (4) is uniformly stirred by a magnetic stirrer (4.1) for one hour in advance and then enters Sequencing Batch Reactor (SBR) through a second water inlet pump (5.2), and anaerobic stirring is carried out for 6-8 hours in each period, so that stirring is finished when the hydrolysis acidification rate reaches 80-95%; and (3) starting a third water inlet pump (5.3) and a fourth water inlet pump (5.5) to pump the sewage in the domestic sewage inlet water tank (1) and the nitrifying liquid intermediate water tank (3) into the Sequencing Batch Reactor (SBR), enabling the mass concentration ratio of nitrate nitrogen to ammonia nitrogen to meet a set value of 1-1.2: 1, carrying out anoxic stirring for 3 hours to carry out short-range denitrification coupling anaerobic ammonia oxidation reaction, settling for 10 minutes after stopping stirring, draining water, standing, and entering the next period.

The test result shows that: when the inflow water is low-C/N urban domestic sewage, the device can obtain a better treatment effect, after the system runs stably, the COD (chemical oxygen demand) of the outflow water is 40-50 mg/L, the ammonia nitrogen concentration is below 2mg/L, the total nitrogen is less than 10mg/L, and the sludge reduction effect can reach 50-70% in the sludge reduction stage of hydrolysis acidification.

The foregoing is a detailed description of the invention that will enable those skilled in the art to better understand and utilize the invention, and it is not to be limited thereby, since various modifications and changes may be made by those skilled in the art without departing from the scope of the invention.