CN115196750A

CN115196750A - Micro-aerobic MMBR sewage treatment device and treatment process thereof

Info

Publication number: CN115196750A
Application number: CN202210860838.2A
Authority: CN
Inventors: 李怀章
Original assignee: Shandong Runtian Environmental Protection Equipment Co ltd
Current assignee: Shandong Runtian Environmental Protection Equipment Co ltd
Priority date: 2022-07-22
Filing date: 2022-07-22
Publication date: 2022-10-18

Abstract

The invention belongs to the technical field of sewage treatment, and particularly relates to a micro-aerobic MMBR sewage treatment device and a treatment process thereof, which comprises an anaerobic zone, a micro-aerobic MBR zone, a clear water zone, an equipment zone, a water production pump, a DO monitor, a liquid level meter, an aeration pipeline and a water production pipeline, wherein the anaerobic zone and the micro-aerobic MBR zone are separated by a first partition plate, domestic sewage enters a regulating tank after large impurities are filtered by a septic tank and a coarse and fine grille, and enters the sewage treatment system through a lift pump, the liquid level meter is arranged in the micro-aerobic MBR zone, the water production pump runs for 8 to 10 minutes and stops for 1 to 2 minutes to form a water production period, the intermittent running mode can reduce transmembrane pressure difference and recover membrane flux in time, and the water production pump can automatically run under the control of the liquid level meter.

Description

Micro-aerobic MMBR sewage treatment device and treatment process thereof

Technical Field

The invention belongs to the technical field of sewage treatment, and particularly relates to a micro-aerobic MMBR sewage treatment device and a treatment process thereof.

Background

The sewage treatment industry is a large energy-consuming household, according to statistics, the power consumption of sewage treatment plants accounts for 0.26% of the total power consumption of the whole country in 2014 in China, and the proportion of the power consumption accounts for more than 2% in industrial wastewater treatment and sludge treatment. The data show that the electricity consumption of sewage per unit volume treated by sewage treatment plants in China is about 0.15-0.28 kWh/m < 3 >, wherein the proportion of the electricity consumption of an aeration blower is 56.2%, and although the energy consumption of different sewage treatment processes is different, the maximum proportion of the overall energy consumption of the aeration system is the fact, so that the energy-saving and consumption-reducing key point of the sewage treatment plants is to optimize the treatment process and reduce the energy consumption of the blower, and in addition, the concentration of C0D of inlet water of municipal sewage treatment plants in China is low, so that the shortage of carbon source needs to be realized by additionally adding carbon source to achieve the purposes of denitrification and dephosphorization.

Therefore, the invention provides a Micro-aerobic MMBR sewage treatment device and a treatment process thereof, wherein the MMBR is an abbreviation of Micro-aerobic Membrane biorator, and is abbreviated as MMBR in the text.

Disclosure of Invention

In order to make up for the defects of the prior art and solve the problems of large energy consumption, large occupied area and poor treatment effect of the conventional sewage treatment equipment, the invention provides the micro-aerobic MMBR sewage treatment device and the treatment process thereof.

The technical scheme adopted by the invention for solving the technical problem is as follows: the invention relates to a micro-aerobic MMBR sewage treatment device which comprises an anaerobic zone, a micro-aerobic MBR zone, a clean water zone, an equipment zone, a first partition plate, a second partition plate, a biological filler box, a stirring device, a micro-porous aerator, a perforated aeration pipe, a blower, an MBR membrane component, a first water inlet pipe, a second water inlet pipe, a first valve, a second valve, a water production pump, a DO monitor, a liquid level meter, an aeration pipeline and a water production pipeline.

Preferably, an MBR membrane module is arranged in the micro-aerobic MBR zone, and a perforated aeration pipe is arranged at the lower part of the MBR membrane module.

Preferably, the MBR membrane module is connected with a water production pump through a water production pipeline.

Preferably, it has first inlet tube to connect inside and outside the anaerobic zone, be connected with the second inlet tube on the first inlet tube, the second inlet tube sets up in little oxygen MBR district, install first valve on the first inlet tube, install the second valve on the second inlet tube.

Preferably, a DO monitor and a liquid level meter are arranged in the micro-aerobic MBR zone.

Preferably, a stirring device is installed at the bottom of the anaerobic zone, the stirring device consists of a stirring motor and blades, and the blades are installed on a rotating shaft of the stirring motor.

Preferably, a biological stuffing box is arranged in the middle of the anaerobic zone, and a three-dimensional elastic stuffing is arranged in the biological stuffing box.

A treatment process of micro-aerobic MMBR sewage comprises the following steps:

s1: the domestic sewage enters the regulating tank after large impurities are filtered by the septic tank and the coarse and fine grids, enters the sewage treatment system through the lift pump, the inlet water is divided into two paths, one path of the inlet water enters the anaerobic zone through the first water inlet pipe, the other path of the inlet water enters the micro-aerobic MBR zone through the second water inlet pipe, the sewage entering the anaerobic zone flows up to the outlet weir after passing through the bottom water distribution system, and overflows into the micro-aerobic MBR zone;

s2: the anaerobic zone is provided with a stirring device, a biological packing box is arranged in the anaerobic zone, a three-dimensional elastic packing is arranged in the biological packing box, and the strand wires of the three-dimensional elastic packing are in a three-dimensional uniformly-arranged radiation state, so that gas, water and a biological membrane are fully mixed, infiltrated, contacted and exchanged, the biological membrane can be uniformly implanted on each strand wire, good activity and gap variability are kept, and a larger and larger specific surface area can be obtained in the operation process;

s3: the microporous aerator and the perforated aeration pipe are connected with the air blower through aeration pipelines, the perforated aeration pipe is positioned right below the MBR membrane component, and the microporous aerator is distributed at the bottom of the area outside the membrane frame;

s4: the MBR membrane module is connected with a water production pump through a water production pipeline, a liquid level meter is arranged in a micro-aerobic MBR area, the water production pump runs for 8 to 10 minutes and stops for 1 to 2 minutes to form a water production period, time parameters can be finely adjusted, transmembrane pressure difference can be reduced in an intermittent running mode, membrane flux can be recovered in time, and the water production pump can automatically run under the control of the liquid level meter. By the efficient interception effect of the MBR membrane on microorganisms, dominant strains are enriched, and aerobic bacteria, facultative bacteria and anaerobic bacteria can exist simultaneously;

s5: a DO monitor is arranged in the micro-aerobic MBR area, and the fan can automatically adjust the aeration quantity according to the DO concentration; controlling DO concentration to be 0.2-1mg/L, controlling aeration intensity of the MBR area to enable the MBR area to be in a micro-aerobic state, wherein aerobic bacteria, facultative bacteria and anaerobic bacteria have functions which are not existed in a single aerobic environment under a micro-aerobic reaction environment, and synchronous nitrification and denitrification, short-cut nitrification and denitrification and anaerobic ammonia oxidation and denitrification can be realized; the screening function of the micro-aerobic environment can promote the growth of suitable dominant species, such as facultative bacteria and anaerobic bacteria, and has an inhibiting function on other species which do not adapt to the environment, and the stimulating function is greater than the inhibiting function; meanwhile, DO has great influence on the growth of the activated sludge, the growth of anaerobic ammonium oxidation bacteria is promoted by optimizing nutritional conditions and environmental conditions in a micro-aerobic environment, the proportion of facultative bacteria and anaerobic bacteria in an activated sludge microbial community structure is greatly increased, the demand of the microbial community on oxygen is reduced, the dissolved oxygen concentration is 0.2 to 0.5 mg/L, heterotrophic bacteria begin to decompose and utilize organic matters in inlet water, ammonia Oxidizing Bacteria (AOB) are dominant in nitrobacteria, the nitration reaction is mainly controlled in an ammonia oxidation stage, the concentrations of COD, NH4+ -N and TN in outlet water are all reduced, and the pollutant discharge level A standard of a town sewage plant can be reached.

The invention has the following beneficial effects:

the invention relates to a micro-aerobic MMBR sewage treatment device and a treatment process thereof, wherein domestic sewage enters an adjusting tank after being filtered by a septic tank and a coarse and fine grid, enters a sewage treatment system through a lift pump, the sewage enters an anaerobic zone through a first water inlet pipe, the sewage enters a micro-aerobic MBR zone through a second water inlet pipe, the flow of the sewage in the two ways can be adjusted through valves respectively, the sewage entering the anaerobic zone flows up to a water outlet weir after passing through a bottom water distribution system, overflows to the micro-aerobic MBR zone, the anaerobic zone is provided with a stirring device, a biological filler box is arranged in the anaerobic zone, a three-dimensional elastic filler is arranged in the biological filler box, the thread lines of the three-dimensional elastic filler are in a three-dimensional uniformly-arranged radiation state, so that air, water and biological membranes are fully mixed, permeated, contacted and exchanged, the biological membrane can be uniformly implanted on each strand, good activity and gap variability are kept, and larger specific surface area can be obtained in the operation process, the microporous aerator and the perforated aeration pipe are connected with an air blower through aeration pipelines, the perforated aeration pipe is positioned under an MBR (membrane bioreactor) membrane assembly, the microporous aerator is distributed at the bottom of an area outside a membrane frame, a DO monitor is arranged in a micro-oxygen MBR area, the air blower can automatically adjust aeration quantity according to DO concentration, the MBR membrane assembly is connected with a water production pump through a water production pipeline, sewage enters a clear water area through the suction effect of the water production pump, a liquid level meter is arranged in the micro-oxygen MBR area, the water production pump stops running for 8 to 10 minutes and stops for 1 to 2 minutes to form a water production period, time parameters can be finely adjusted, transmembrane pressure difference can be reduced in an intermittent operation mode, membrane flux can be timely recovered, and the water production pump can automatically run under the control of the liquid level meter. Compared with the traditional sewage treatment process, the method can save oxygen supply by more than 60 percent, can reduce or not additionally add carbon sources and chemical phosphorus removal agents, has the outstanding advantages of near zero emission of excess sludge and the like, and achieves the aims of saving energy, reducing material consumption and reducing carbon emission.

Drawings

The invention will be further explained with reference to the drawings.

FIG. 1 is a schematic process flow diagram of the practice of the present invention;

FIG. 2 is a schematic structural diagram of an apparatus according to an embodiment;

in the figure: 1. an anaerobic zone; 2. a micro-aerobic MBR zone; 3. a clear water zone; 4. an equipment area; 5. a first separator; 6. a second separator; 7. a biological stuffing box; 8. a stirring device; 9. a microporous aerator; 10. perforating an aeration pipe; 11. a blower; 12. an MBR membrane module; 13. a first water inlet pipe; 14. a second water inlet pipe; 15. a first valve; 16. a second valve; 17. a water production pump; 18. a DO monitor; 19. a liquid level meter; 20. an aeration pipe; 21. a water production pipeline.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

Examples

As shown in fig. 1 to 2, the micro-aerobic MMBR sewage treatment device comprises an anaerobic zone 1, a micro-aerobic MBR zone 2, a clean water zone 3, a facility zone 4, a first partition plate 5, a second partition plate 6, a biological filler box 7, a stirring device 8, a micro-porous aerator 9, a perforated aeration pipe 10, a blower 11, an MBR membrane module 12, a first water inlet pipe 13, a second water inlet pipe 14, a first valve 15, a second valve 16, a water production pump 17, a DO monitor 18, a liquid level meter 19, an aeration pipeline 20 and a water production pipeline 21, wherein the anaerobic zone 1 and the micro-aerobic MBR zone 2 are separated by the first partition plate 5, an overflow port is formed on the first partition plate 5, and the micro-aerobic MBR zone 2 and the clean water zone 3 are separated by the second partition plate 6, the clear water area 3 and the facility area 4 are isolated by a sealing plate, an air blower 11 and a water producing pump 17 are arranged in the facility area 4, a drain pipe is connected outside the clear water area 3, a water guide pipe is connected between the clear water area 3 and the water producing pump 17, a microporous aerator 9 and a perforated aeration pipe 10 are arranged in the micro-aerobic MBR area 2, the microporous aerator 9 and the perforated aeration pipe 10 are connected with the air blower 11 through an aeration pipeline 20, when water is produced, the water producing pump works for 8 to 10min, the water producing period is 1 to 2min is stopped for reducing the pressure difference of MBR and recovering the membrane flux, a stirring device 8 is arranged at the bottom of the anaerobic area 1, the stirring device 8 consists of a stirring motor and blades, and blades are arranged on a rotating shaft of the stirring motor. The traditional treatment process generally comprises the steps of feeding water all the way, and then sequentially entering each reaction tank, so that the condition that a carbon source is insufficient and a carbon source needs to be additionally added for a system needing nitrogen and phosphorus removal can be caused, the water feeding mode is changed, the water feeding mode is divided into two ways, one way of sewage enters an anaerobic zone, one way of sewage enters a micro-aerobic MBR zone, precious carbon source in the sewage is fully utilized, and the addition of external carbon source can be reduced or avoided.

Domestic sewage gets into the equalizing basin after septic tank, thickness grid filter big impurity, gets into this sewage treatment system through the elevator pump, and the branch is two the tunnel into, and sewage gets into the anaerobic zone all the way, and sewage gets into the micro-oxygen MBR district all the way, and the sewage that gets into the anaerobic zone rises to the play weir after bottom water distribution system, and the overflow gets into the micro-oxygen MBR district.

An MBR membrane module 12 is arranged in the micro-oxygen MBR area 2, a perforated aeration pipe 10 is arranged at the lower part of the MBR membrane module 12, membrane wires are washed and shaken, dissolved oxygen is provided for the micro-oxygen MBR area, the MBR membrane module 12 is connected with a water production pump 17 through a water production pipeline 21, a first water inlet pipe 13 is connected in the anaerobic area 1, a second water inlet pipe 14 is connected on the first water inlet pipe 13, the second water inlet pipe 14 is arranged in the micro-oxygen MBR area 2, a first valve 15 is installed on the first water inlet pipe 13, a second valve 16 is installed on the second water inlet pipe 14, a DO monitor 18 and a liquid level meter 19 are arranged in the micro-oxygen MBR area 2, the dissolved oxygen concentration of the micro-oxygen MBR area 2 is controlled to be 0.2 to 1mg/L, the sludge concentration is 10000 to 25000mg/L, the DO monitor 18 is arranged, the aeration amount is automatically adjusted according to the DO concentration, the water production pump 17 is controlled by the liquid level meter 19 to work, a biological filler box 7 is arranged in the middle part of the anaerobic area 1, and a three-dimensional elastic filler is arranged in the biological filler box 7.

A treatment process of micro-aerobic MMBR sewage comprises the following steps:

s1: after large impurities in domestic sewage are filtered by a septic tank and a coarse-fine grid, the domestic sewage enters an adjusting tank and enters the sewage treatment system through a lift pump, the inlet water is divided into two paths, one path of the inlet water enters an anaerobic zone 1 through a first water inlet pipe 13, the other path of the inlet water enters a micro-aerobic MBR zone 2 through a second water inlet pipe 14, the flow of the inlet water in the two paths of the inlet water can be adjusted through a valve 15 and a valve 16 respectively, the sewage entering the anaerobic zone 1 is lifted to a water outlet weir after passing through a bottom water distribution system, and overflows and enters the micro-aerobic MBR zone 2;

s2: the anaerobic zone 1 is provided with a stirring device 8, a biological filler box 7 is arranged in the anaerobic zone 1, a three-dimensional elastic filler is arranged in the biological filler box 7, and the strand wires of the three-dimensional elastic filler are in a three-dimensional uniformly-arranged radiation state, so that air, water and a biological membrane are fully mixed, infiltrated, contacted and exchanged, the biological membrane can be uniformly implanted on each strand wire, good activity and gap variability are kept, and a larger and larger specific surface area can be obtained in the operation process;

s3: the microporous aerator 9 and the perforated aeration pipe 10 are connected with the blower 11 through an aeration pipeline 20, the perforated aeration pipe 10 is positioned right below the MBR membrane component 12, and the microporous aerator 9 is distributed at the bottom of the area outside the membrane frame;

s4: the MBR membrane module is connected with a water production pump through a water production pipeline, a liquid level meter is arranged in a micro-aerobic MBR area, the water production pump runs for 8 to 10 minutes and stops for 1 to 2 minutes to form a water production period, time parameters can be finely adjusted, transmembrane pressure difference can be reduced in an intermittent running mode, membrane flux can be recovered in time, and the water production pump can automatically run under the control of the liquid level meter;

s5: the micro-oxygen MBR area is provided with a DO monitor, and the fan can automatically adjust the aeration quantity according to the DO concentration.

The MMBR process sewage pollutant removal principle:

the MBR area is in a micro-aerobic state by controlling the aeration intensity of the MBR area, and the MBR membrane has high-efficiency interception effect on microorganisms, so that dominant strains are enriched, aerobic bacteria, facultative bacteria and anaerobic bacteria exist simultaneously, and the combined action of the microbial colonies enables the MBR area to have the function which is not available in a single aerobic environment in a low DO reaction environment. The system realizes denitrification through Synchronous Nitrification and Denitrification (SND) or anaerobic ammonia oxidation (ANAMMOXIC), and in a micro-aerobic environment, compared with the traditional biological denitrification process, the SND process can be carried out in the same reactor, so that the addition of a carbon source can be reduced or even not required, the nitrification alkali consumption and the denitrification alkali production can be well complemented, the reaction time can be shortened, the nitrite type SND can be obviously reduced, and the supply of oxygen can be obviously reduced, so that the energy consumption is saved, the demand of the carbon source is further reduced, and the denitrification efficiency is improved; the screening function of the micro-aerobic environment can promote the growth of suitable dominant species, such as facultative bacteria and anaerobic bacteria, and has an inhibiting effect on other species which do not adapt to the environment, and the stimulating effect is greater than the inhibiting effect. The standard volume of the microbial metabolites under the micro-aerobic environment is smaller, which shows that the micro-aerobic microbial activity is lower than that of the aerobic environment, and the sludge yield is correspondingly reduced. Meanwhile, DO has a great influence on the growth of the activated sludge, the growth of anaerobic ammonium oxidation bacteria is promoted by optimizing nutritional conditions and environmental conditions under a micro-aerobic environment, the proportion of facultative bacteria and anaerobic bacteria in an activated sludge microbial community structure is greatly increased, the demand of the microbial community on oxygen is reduced, the dissolved oxygen concentration is 0.2-0.5 mg/L, heterotrophic bacteria begin to decompose and utilize organic matters in inlet water, ammonia Oxidizing Bacteria (AOB) are dominant in nitrobacteria, the nitration reaction is mainly controlled in an ammonia oxidation stage, the COD, NH4+ -N and TN in outlet water are reduced, and the first-level A standard of pollutant discharge of urban sewage plants can be reached.

The front, the back, the left, the right, the upper and the lower are all based on figure 1 in the attached drawings of the specification, according to the standard of the observation angle of a person, the side of the device facing an observer is defined as the front, the left side of the observer is defined as the left, and the like.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience in describing the present invention and for simplifying the description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the scope of the present invention.

The foregoing shows and describes the general principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A micro-aerobic MMBR sewage treatment device is characterized by comprising an anaerobic zone (1), a micro-aerobic MBR zone (2), a clean water zone (3), a facility zone (4), a first partition plate (5), a second partition plate (6), a biological stuffing box (7), a stirring device (8), a micro-pore aerator (9), a perforated aeration pipe (10), an air blower (11), an MBR membrane component (12), a first water inlet pipe (13), a second water inlet pipe (14), a first valve (15), a second valve (16), a water production pump (17), a DO monitor (18), a liquid level meter (19), an aeration pipeline (20) and a water production pipeline (21), wherein the MBR zone (1) and the micro-aerobic zone (2) are separated by the first partition plate (5), an overflow port is formed in the first partition plate (5), the micro-aerobic zone (2) and the clean water zone (3) are separated by the second partition plate (6), the water production pump (11) and the micro-aerobic zone (3) are connected by the micro-pore aerator (17), the water production pump (17) and the micro-aeration pipe (9) are arranged in the water production zone (3), the microporous aerator (9) and the perforated aerator pipe (10) are connected with a blower (11) through an aeration pipeline (20).

2. The micro-aerobic MMBR sewage treatment plant of claim 1, wherein: an MBR (membrane bioreactor) membrane module (12) is arranged in the micro-aerobic MBR area (2), and a perforated aeration pipe (10) is arranged at the lower part of the MBR membrane module (12).

3. The sewage treatment plant of claim 1, wherein the sewage treatment plant comprises: the MBR membrane module (12) is connected with a water production pump (17) through a water production pipeline (21).

4. The micro-aerobic MMBR sewage treatment plant of claim 1, wherein: it has first inlet tube (13) to connect inside and outside anaerobic zone (1), be connected with second inlet tube (14) on first inlet tube (13), second inlet tube (14) set up in little oxygen MBR district (2), install first valve (15) on first inlet tube (13), install second valve (16) on second inlet tube (14).

5. The sewage treatment plant of claim 1, wherein the sewage treatment plant comprises: and a DO monitor (18) and a liquid level meter (19) are arranged in the micro-aerobic MBR area (2).

6. The sewage treatment plant of claim 1, wherein the sewage treatment plant comprises: agitating unit (8) are installed to the bottom in anaerobic zone (1), agitating unit (8) comprise agitator motor and blade, install the blade in agitator motor's the pivot.

7. The sewage treatment plant of claim 1, wherein the sewage treatment plant comprises: the middle part of the anaerobic zone (1) is provided with a biological stuffing box (7), and a three-dimensional elastic stuffing is arranged in the biological stuffing box (7).

8. A treatment process of micro-aerobic MMBR sewage is characterized by comprising the following steps:

s1: the domestic sewage enters an adjusting tank after large impurities are filtered by a septic tank and a coarse-fine grid, enters the sewage treatment system through a lift pump, the inlet water is divided into two paths, one path of the inlet water enters an anaerobic zone through a first inlet pipe, the other path of the inlet water enters a micro-aerobic MBR zone through a second inlet pipe, the sewage entering the anaerobic zone flows up to a water outlet weir after passing through a bottom water distribution system, and overflows and enters the micro-aerobic MBR zone;

s4: the MBR membrane module is connected with a water production pump through a water production pipeline, a liquid level meter is arranged in a micro-aerobic MBR area, the water production pump stops running for 8 to 10 minutes and stops running for 1 to 2 minutes to form a water production cycle, time parameters can be finely adjusted, transmembrane pressure difference can be reduced in an intermittent running mode, membrane flux can be recovered in time, and the water production pump can automatically run under the control of the liquid level meter; by the efficient interception effect of the MBR membrane on microorganisms, dominant strains are enriched, and aerobic bacteria, facultative bacteria and anaerobic bacteria can exist simultaneously;

s5: a DO monitor is arranged in the micro-aerobic MBR area, and the fan can automatically adjust the aeration quantity according to the DO concentration; controlling DO concentration to be 0.2 to 1mg/L, controlling aeration intensity of an MBR area to enable the MBR area to be in a micro-aerobic state, wherein aerobic bacteria, facultative bacteria and anaerobic bacteria have functions which are not existed in a single aerobic environment under a micro-aerobic reaction environment, and synchronous nitrification-denitrification, short-cut nitrification-denitrification and anaerobic ammonia oxidation denitrification can be realized; the screening function of the micro-aerobic environment can promote the growth of suitable dominant species, such as facultative bacteria and anaerobic bacteria, and has an inhibiting function on other species which do not adapt to the environment, and the stimulating function is greater than the inhibiting function; meanwhile, DO has great influence on the growth of the activated sludge, the growth of anaerobic ammonium oxidation bacteria is promoted by optimizing nutritional conditions and environmental conditions in a micro-aerobic environment, the proportion of facultative bacteria and anaerobic bacteria in an activated sludge microbial community structure is greatly increased, the demand of the microbial community on oxygen is reduced, the dissolved oxygen concentration is 0.2 to 0.5 mg/L, heterotrophic bacteria begin to decompose and utilize organic matters in inlet water, ammonia Oxidizing Bacteria (AOB) are dominant in nitrobacteria, the nitration reaction is mainly controlled in an ammonia oxidation stage, the concentrations of COD, NH4+ -N and TN in outlet water are all reduced, and the pollutant discharge level A standard of a town sewage plant can be reached.