Method for simultaneous biological nitrogen and phosphorus removal using MABR

Abstract

The present invention discloses a method for synchronous biological denitrification and phosphorus removal using MABR, wherein the original wastewater is divided into two parts and respectively introduced into the denitrification zone and the dephosphorization zone in the sewage treatment system, and the amount of wastewater entering the denitrification zone is greater than the amount of wastewater entering the dephosphorization zone; the denitrification zone is provided with a plurality of MABR membrane modules, the dissolved oxygen concentration of the denitrification zone is monitored, and the dissolved oxygen concentration of the denitrification zone is maintained at 0.1mg / L to 0.3mg / L, and the effluent of the denitrification zone enters the dephosphorization zone; the dissolved oxygen concentration of the dephosphorization zone is monitored, and the dissolved oxygen concentration of the dephosphorization zone is maintained at 2mg / L to 4mg / L; the effluent of the dephosphorization zone enters the solid-liquid separation zone, and the supernatant of the solid-liquid separation zone is refluxed to the denitrification zone, and a part of the sludge at the bottom of the solid-liquid separation zone is discharged from the system as residual sludge, and a part of it is refluxed to the dephosphorization zone. The method for synchronous biological denitrification and phosphorus removal using MABR provided by the present invention can improve the efficiency of sewage treatment.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a method for synchronous biological nitrogen and phosphorus removal by using MABR. Background Art

[0002] Nitrogen and phosphorus in sewage (wastewater) are the main elements that affect water quality. Biological treatment is a low-cost, environmentally friendly treatment method. For this purpose, various denitrification and phosphorus removal processes have been developed, including the Badanfu simultaneous denitrification and phosphorus removal process, the AAO simultaneous denitrification and phosphorus removal process, the biological rotary disc simultaneous denitrification and phosphorus removal process, etc. Most of them are single activated sludge method or biofilm method.

[0003] As we all know, denitrification microorganisms require a long sludge age (20~25d), while phosphorus removal microorganisms require a short sludge age (3~5d), which creates a contradiction between denitrification and phosphorus removal. Generally speaking, the control conditions of biological denitrification are relatively strict and difficult to achieve, while phosphorus removal can be assisted by chemical agents. Therefore, conventional biological treatments are mainly based on biological denitrification to ensure a long sludge age for the biological treatment system, but sacrifice the effect of biological phosphorus removal, and instead use chemical phosphorus removal to assist in achieving high-standard emission requirements (total phosphorus less than 0.5mg / L or 0.3mg / L, or even 0.1mg / L).

[0004] The single activated sludge method for simultaneous nitrogen and phosphorus removal has a long sludge age and high sludge concentration, consumes more carbon sources, and leads to an imbalance in the carbon-nitrogen ratio. It requires the addition of a certain amount of external carbon source for nitrogen removal. The required operating conditions are relatively harsh, the operation and management are cumbersome, and the requirements for the level of management are high. It only removes part of the phosphorus through microbial assimilation, and the biological phosphorus removal effect is very low, with a removal rate of only 10%~20%.

[0005] The single biofilm method for nitrogen and phosphorus removal has a low sludge output and a good nitrogen removal effect, but the total phosphorus is difficult to effectively remove in the form of sludge. Therefore, the biological phosphorus removal effect is still not high, only 20%~30%. The biofilm method has a low treatment load and a limited treatment scale, and is not suitable for large-scale sewage treatment plants. Summary of the invention

[0006] The purpose of the present invention is to provide a method for simultaneous biological denitrification and phosphorus removal using MABR, which can alleviate the contradiction between the long sludge age required for biological denitrification and the short sludge age required for biological phosphorus removal, while improving the effects of denitrification and phosphorus removal, reducing the addition of carbon sources and phosphorus removal agents, and reducing energy consumption and sludge production.

[0007] Based on the above problems, the technical solution provided by the present invention is:

[0008] The method of using MABR for simultaneous biological nitrogen and phosphorus removal,

[0009] The two parts of the original wastewater are respectively introduced into the denitrification zone and the dephosphorization zone in the sewage treatment system, wherein the amount of wastewater entering the denitrification zone is greater than the amount of wastewater entering the dephosphorization zone;

[0010] The denitrification zone is provided with a plurality of MABR membrane modules, and the dissolved oxygen concentration in the denitrification zone is monitored to maintain the dissolved oxygen concentration in the denitrification zone at 0.1 mg / L to 0.3 mg / L. When the dissolved oxygen concentration does not meet the requirement, the air supply of the plurality of MABR membrane modules is adjusted, and the effluent of the denitrification zone enters the dephosphorization zone;

[0011] The dephosphorization zone is provided with an aerator and a flow pusher to monitor the dissolved oxygen concentration in the dephosphorization zone and maintain the dissolved oxygen concentration in the dephosphorization zone at 2mg / L-4mg / L. When the dissolved oxygen concentration does not meet the requirement, the oxygen supply of the aerator is adjusted;

[0012] The effluent from the dephosphorization zone enters the solid-liquid separation zone, the supernatant from the solid-liquid separation zone flows back to the denitrification zone, part of the sludge at the bottom of the solid-liquid separation zone is discharged from the system as residual sludge, and part of it flows back to the dephosphorization zone;

[0013] Monitor the total nitrogen concentration of the discharged water from the solid-liquid separation zone, and when the total nitrogen concentration in the discharged water is greater than the required discharge value, increase the proportion of the supernatant refluxed to the denitrification zone;

[0014] Monitor the total phosphorus concentration of the discharged water from the solid-liquid separation zone, and when the total phosphorus concentration in the discharged water is greater than the discharge requirement value, increase the sludge discharge amount;

[0015] Monitoring the sludge concentration in the phosphorus removal zone, and controlling the sludge concentration by controlling the sludge return flow;

[0016] The COD concentration in the phosphorus removal zone is monitored, and the COD / TP in the phosphorus removal zone is ensured to be greater than 17 by adjusting the amount of wastewater raw water entering the phosphorus removal zone.

[0017] In some embodiments, the amount of wastewater entering the denitrification zone is 80-90% of the total amount of the raw wastewater, and the amount of wastewater entering the dephosphorization zone is 10-20% of the total amount of the raw wastewater.

[0018] In some of the embodiments, the sludge return ratio is 30% to 50% of the total amount of wastewater raw water.

[0019] In some of the embodiments, the supernatant reflux ratio is 20% to 50% of the total amount of the wastewater raw water.

[0020] In some embodiments, the sewage treatment system includes a MABR membrane tank, an aerobic tank and a solid-liquid separation tank that are interconnected;

[0021] The MABR membrane pool is the denitrification zone and is provided with a plurality of MABR membrane modules and a first dissolved oxygen monitor inside. The plurality of MABR membrane modules are connected to a gas supply pipeline, and a process gas fan, a process gas flow meter and a process gas regulating valve are sequentially provided on the gas supply pipeline along the air inlet direction;

[0022] The aerobic tank is the dephosphorization zone, the aerator and the flow pusher are arranged at the bottom of the aerobic tank, the aerator is connected to the aeration pipeline, and the aeration fan, the aeration flow meter and the aeration regulating valve are arranged in sequence along the air inlet direction of the aeration pipeline, and the dephosphorization zone is provided with a second dissolved oxygen monitor and a sludge concentration monitor;

[0023] An online total nitrogen monitor and an online total phosphorus monitor are provided in the solid-liquid separation tank. The upper part of the solid-liquid separation tank is connected to the MABR membrane tank via a supernatant reflux pipe. A supernatant reflux pump and a supernatant reflux regulating valve are sequentially provided on the supernatant reflux pipe along the water flow direction. A sludge reflux pipe is connected to the bottom of the solid-liquid separation tank. A sludge reflux pump and a reflux sludge regulating valve are sequentially provided on the sludge reflux pipe along the sludge discharge direction. The sludge reflux pipe is also connected to a sludge discharge pipe, and a sludge discharge regulating valve is provided on the sludge discharge pipe.

[0024] In some of the embodiments, the phosphorus removal zone is provided with a COD online monitor.

[0025] In some of the embodiments, the denitrification zone and the phosphorus removal zone are connected to a water inlet pipe, and a raw water regulating valve is provided on the water inlet pipe section connected to the phosphorus removal zone.

[0026] In some of the embodiments, the MABR membrane tank is separated from the aerobic tank by a partition, and a through hole connecting the denitrification zone and the dephosphorization zone is provided at the bottom of the partition.

[0027] Compared with the prior art, the advantages of the present invention are:

[0028] 1. The denitrification area and phosphorus removal area adopt the MABR biofilm method and activated sludge method respectively. The biological denitrification and biological phosphorus removal functions are basically independent, and the long sludge age required for denitrification and the short sludge age required for phosphorus removal can be controlled respectively, which is simple to operate;

[0029] 2. The biological denitrification efficiency can reach more than 90%, and the biological phosphorus removal efficiency is 50%~70%, which is higher than 80% and 20% of the single activated sludge method or the single biofilm method;

[0030] 3. By controlling the oxygen supply in the MABR membrane cavity, multiple denitrification functions such as simultaneous nitrification and denitrification, short-range nitrification and denitrification, nitrite-anaerobic ammonium oxidation, etc. can be achieved. The denitrification removal efficiency is stable and the removal rate is high, which can cope with the impact of water quality, water volume and water temperature;

[0031] 4. The unique biofilm structure of MABR with internal nitrification and external denitrification allows reverse transfer of oxygen, ammonia nitrogen and COD, making full use of the wastewater's own carbon source without the need for an external carbon source. MABR uses bubble-free aeration, and its oxygen utilization rate is more than 40% lower than that of conventional aerators, and its energy consumption is reduced by more than 40%. The biofilm method used by MABR has a long internal microbial food chain, and the sludge output is more than 50% lower than that of the activated sludge method.

[0032] 5. The COD removal rate of MABR in the denitrification area can reach 80%~90%, and the COD entering the phosphorus removal area is low, and the sludge production is low;

[0033] 6. The phosphorus removal section has triple phosphorus removal functions of assimilation, sludge adsorption and phosphorus absorption by polyphosphate bacteria. The biological phosphorus removal efficiency can reach 50%~70%. Compared with the single activated sludge method or the single biofilm method, which only removes 10%~30% of the total phosphorus by assimilation, the biological phosphorus removal efficiency is increased by 30%~60%, which can reduce the amount of phosphorus removal agent required for chemical phosphorus removal and the resulting sludge output by 30%~60%;

[0034] 7. By automatically monitoring the total nitrogen and total phosphorus concentrations in the effluent and flexibly adjusting the return ratio of supernatant or sludge, the effluent quality is stable and the compliance rate is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. The accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0036] Figure 1 It is a schematic structural diagram of an embodiment of a sewage treatment system involved in the method for simultaneous biological nitrogen and phosphorus removal using MABR of the present invention;

[0037] in:

[0038] 1. MABR membrane pool; 2. Aerobic pool; 3. Solid-liquid separation pool; 4. MABR membrane assembly; 5. Water inlet pipe; 6. Raw water regulating valve; 7. Air supply pipeline; 8. Process gas fan; 9. Process gas flow meter; 10. Process gas regulating valve; 11. First dissolved oxygen monitor; 12. Aerator; 13. Flow pusher; 14. Aeration pipeline; 15. Aeration fan; 16. Aeration flow meter; 17. Aeration regulating valve; 1 8. Second dissolved oxygen monitor; 19. COD online monitor; 20. Sludge concentration monitor; 21. Total nitrogen online monitor; 22. Total phosphorus online monitor; 23. Supernatant reflux pipe; 24. Supernatant reflux pump; 25. Supernatant reflux regulating valve; 26. Sludge reflux pipe; 27. Sludge reflux pump; 28. Reflux sludge regulating valve; 29. ​​Sludge discharge pipe; 30. Sludge discharge regulating valve; 31. Partition. DETAILED DESCRIPTION

[0039] The above scheme is further described below in conjunction with specific examples. It should be understood that these examples are used to illustrate the present invention and are not limited to the scope of the present invention. The implementation conditions adopted in the examples can be further adjusted according to the conditions of the specific manufacturer, and the unspecified implementation conditions are usually the conditions in conventional experiments.

[0040] See also Figure 1 , is a structural schematic diagram of an embodiment of the present invention, which provides a sewage treatment system involving a method for synchronous biological nitrogen removal and phosphorus removal using MABR, comprising a MABR membrane tank 1, an aerobic tank 2 and a solid-liquid separation tank 3 that are interconnected, wherein the MABR membrane tank 1 and the aerobic tank 2 are both connected to a water inlet pipe 5, that is, the two parts of the original wastewater enter the MABR membrane tank 1 and the aerobic tank 2 respectively.

[0041] The MABR membrane pool 1 is a denitrification zone and is provided with a plurality of MABR membrane modules 4 and a first dissolved oxygen monitor 11 inside. The plurality of MABR membrane modules 4 are connected to a gas supply pipeline 7. A process gas blower 8, a process gas flow meter 9 and a process gas regulating valve 10 are provided in sequence along the air inlet direction on the gas supply pipeline 7. The process gas blower 8 introduces oxygen into the membrane cavity of the MABR membrane module 4. The first dissolved oxygen monitor 11 monitors the dissolved oxygen concentration in the MABR membrane pool 1. The oxygen intake amount is adjusted by the process gas regulating valve 10 to control the dissolved oxygen concentration in the MABR membrane pool 1.

[0042] The aerobic pool 2 is separated from the MABR membrane pool 1 by a partition 31 . A through hole connecting the MABR membrane pool 1 and the aerobic pool 2 is provided at the bottom of the partition 31 . The effluent treated by the MABR membrane pool 1 enters the aerobic pool 2 .

[0043] The aerobic tank 2 is a phosphorus removal zone. An aerator 12 and a flow promoter 13 are provided at the bottom of the aerobic tank 2 to fully mix the mud-water mixture in the horizontal and vertical directions. The aerator 12 is connected to an aeration pipeline 14. An aeration fan 15, an aeration flowmeter 16 and an aeration regulating valve 17 are provided in sequence on the aeration pipeline 14 along the air inlet direction. A second dissolved oxygen monitor 18 and a sludge concentration monitor 20 are provided in the phosphorus removal zone. The dissolved oxygen in the phosphorus removal zone is monitored by the second dissolved oxygen monitor 18 to adjust the aeration amount of the aerator 12. The sludge concentration in the phosphorus removal zone is monitored by the sludge concentration monitor 20 to adjust the sludge return amount.

[0044] The solid-liquid separation tank 3 is connected to the aerobic tank 2 via a pipeline. An online total nitrogen monitor 21 and an online total phosphorus monitor 22 are provided in the solid-liquid separation tank 3. The upper part of the solid-liquid separation tank 3 is connected to the MABR membrane tank 1 via a supernatant reflux pipe 23. A supernatant reflux pump 24 and a supernatant reflux regulating valve 25 are provided on the supernatant reflux pipe 23 along the water flow direction. A sludge reflux pipe 26 is connected to the bottom of the solid-liquid separation tank 3. A sludge reflux pump 27 and a reflux sludge regulating valve 28 are provided in sequence on the sludge reflux pipe 26 along the sludge discharge direction. The sludge reflux pipe 26 is also connected to a sludge discharge pipe 29, and a sludge discharge regulating valve 30 is provided on the sludge discharge pipe 29.

[0045] In order to further optimize the implementation effect of the present invention, a COD online monitor 19 is provided in the phosphorus removal zone to ensure that the phosphorus removal zone has a certain organic matter concentration to meet the growth requirements of polyphosphate bacteria. When the organic matter concentration cannot meet the growth requirements of polyphosphate bacteria, the wastewater inflow of the phosphorus removal zone can be increased. The denitrification zone and the phosphorus removal zone are both connected to the water inlet pipe 5. A raw water regulating valve 6 is provided on the water inlet pipe section connected to the phosphorus removal zone. The wastewater inflow of the phosphorus removal zone is adjusted by the raw water regulating valve 6 to meet the energy requirements of polyphosphate bacteria for polyphosphate.

[0046] The sewage treatment method of the above sewage treatment system is:

[0047] The two parts of the original wastewater are respectively introduced into the denitrification zone and the dephosphorization zone in the sewage treatment system, and the amount of wastewater entering the denitrification zone is greater than the amount of wastewater entering the dephosphorization zone;

[0048] Monitor the dissolved oxygen concentration in the denitrification zone and maintain the dissolved oxygen concentration in the denitrification zone at 0.1mg / L to 0.3mg / L. When the dissolved oxygen concentration does not meet the requirements, adjust the gas supply of multiple MABR membrane modules;

[0049] Monitor the dissolved oxygen concentration in the dephosphorization zone and maintain it at 2mg / L to 4mg / L. When the dissolved oxygen concentration does not meet the requirements, adjust the oxygen supply of the aerator.

[0050] The effluent from the phosphorus removal zone enters the solid-liquid separation zone, the supernatant from the solid-liquid separation zone flows back to the denitrification zone, part of the sludge at the bottom of the solid-liquid separation zone is discharged from the system as residual sludge, and part of it flows back to the phosphorus removal zone;

[0051] Monitor the total nitrogen concentration of the discharged water from the solid-liquid separation area. When the total nitrogen concentration in the discharged water is greater than the required discharge value, increase the proportion of the supernatant returned to the denitrification area.

[0052] Monitor the total phosphorus concentration of the discharge water from the solid-liquid separation area. When the total phosphorus concentration in the discharge water is greater than the discharge requirement value, increase the sludge discharge;

[0053] Monitor the sludge concentration in the phosphorus removal area and control the sludge concentration by controlling the sludge return flow;

[0054] Monitor the COD concentration in the phosphorus removal area and ensure that the COD / TP in the phosphorus removal area is greater than 17 by adjusting the amount of wastewater entering the phosphorus removal area.

[0055] Among them, the amount of wastewater entering the denitrification zone is 80-90% of the total amount of raw wastewater, and the amount of wastewater entering the phosphorus removal zone is 10-20% of the total amount of raw wastewater. The amount of wastewater in the denitrification zone and the phosphorus removal zone is adjusted according to the COD concentration in the wastewater.

[0056] The MABR layout in the denitrification area adopts the full membrane method, that is, all biofilm method, the mixed liquor suspended solids (SS) is less than 200 mg / L, the sludge age is 25~35 days, and the hydraulic retention time (HRT) varies according to the total nitrogen concentration of the raw water. For general municipal sewage, the HRT is 12~18h. For industrial wastewater, the HRT is 24~96h. The nitrogen nitrification rate of the MABR membrane component is maintained at 2~5g / (㎡.d), and the dissolved oxygen in the mixed liquor is less than 0.3mg / L. The total nitrogen removal rate in this area is 85%~90%, the ammonia nitrogen removal rate is greater than 95%, and the COD removal rate is greater than 90%. The MABR membrane component is equipped with an airlift mixing unit, which uses the process gas tail gas as the airlift power for up and down circulation and mixing.

[0057] The phosphorus removal area adopts the activated sludge method. For general municipal sewage, the sludge concentration MLSS is guaranteed to be 4000~5000mg / L, ensuring a certain sludge adsorption and phosphorus removal effect. The sludge age is 2~4 days, and the sludge age is controlled according to the total phosphorus concentration of the discharge water. The dissolved oxygen in this area is 2~4mg / L to ensure the aerobic environment required for polyphosphate bacteria to absorb phosphorus, and at the same time ensure that COD / TP is greater than 17 to prevent COD from being too low to affect the energy required for polyphosphate bacteria to absorb phosphorus. The biological phosphorus removal rate in this area is 50%~60%.

[0058] The sludge return ratio is 30% to 50% of the total amount of wastewater raw water, and the supernatant return ratio is 20% to 50% of the total amount of wastewater raw water, which is adjusted according to the total nitrogen concentration and total phosphorus concentration in the discharged water.

[0059] This method can treat municipal sewage with low nitrogen and phosphorus concentrations, and can also treat industrial wastewater with high nitrogen and phosphorus concentrations (garbage leachate, restaurant waste liquid, aquaculture wastewater, sludge press liquid, starch wastewater, etc.). For wastewater with high nitrogen and phosphorus concentrations, the nitrogen nitrification rate of the MABR membrane module can reach 5~10 g / (㎡.d), and the sludge concentration in the phosphorus removal area can reach 6000~8000 mg / L. The adsorption and phosphorus removal effect is better, and the sludge age can be reduced to 1~3 days.

[0060] A certain amount of microbial carriers such as activated carbon, diatomaceous earth or magnetic powder can be added to the phosphorus removal area to improve the adsorption and phosphorus removal effect, and an activated carbon, diatomaceous earth or magnetic powder recovery device can be set up.

[0061] This method is used to treat municipal sewage, with a total nitrogen removal rate of more than 85%, an ammonia nitrogen removal rate of more than 95%, and no need to add deep denitrification units such as denitrification filters at the back end. The total phosphorus removal rate is 50%~60%, and the discharge standard can be achieved after deep chemical phosphorus removal units such as high-efficiency sedimentation tanks at the back end. When treating various types of industrial wastewater with high nitrogen and phosphorus concentrations, the total nitrogen removal rate is 90%~95%, the ammonia nitrogen removal rate is greater than 97%, and the total phosphorus removal rate is 50%~60%. There is basically no need to set up a denitrification treatment unit. After simple chemical phosphorus removal, the total phosphorus can reach the discharge standard for access to municipal sewers.

[0062] The following are specific embodiments:

[0063] Taking the treatment of 10,000 tons / day of municipal sewage as an example, the influent COD is 400mg / L, ammonia nitrogen is 40mg / L, total nitrogen is 45mg / L, and total phosphorus is 5mg / L. The amount of wastewater entering the denitrification area and the dephosphorization area is 85% and 15% respectively. The following is an explanation of the structure size and control parameters of each area.

[0064] The residence time in the denitrification zone is 12 hours. MABR adopts the full membrane method, the nitrogen nitrification rate is 4g / (㎡.d), the membrane area is 100,000㎡, the single membrane module is 2,400㎡, the process gas consumption is 24Nm³ / h, the gas stripping gas consumption is 10Nm³ / h, and the scrubbing gas consumption is 40Nm³ / h. A total of 42 membrane modules are required. The dissolved oxygen of the mixed liquid on the upper surface of the denitrification zone is 0.1~0.3mg / L, the sludge concentration is less than 200mg / L, and the sludge age is 30 days. The total nitrogen removal rate in this area is greater than 85%, the ammonia nitrogen removal rate is greater than 95%, and the COD removal rate is greater than 90%. The total nitrogen in the effluent is less than 7mg / L, the ammonia nitrogen is less than 2mg / L, and the COD is less than 40mg / L.

[0065] The sludge concentration in the phosphorus removal area is MLSS4000mg / L, the sludge age is 3 days, the dissolved oxygen is 4mg / L, and the COD / TP is greater than 17. When the COD / TP is less than 17, the flow rate of raw water to the phosphorus removal area is appropriately increased to supplement the COD. The biological phosphorus removal rate in this area is 50%, and the total phosphorus in the effluent is less than 2.5mg / L.

[0066] The sludge return ratio in the solid-liquid separation area is generally controlled at 40% of the water inlet, and the supernatant return ratio is 40%~50% of the total water inlet. When the total nitrogen removal rate decreases, the supernatant return ratio is increased. The suspended solids in the effluent are less than 80mg / L, and the discharged water enters the subsequent deep treatment unit. When the total phosphorus in the effluent increases, the residual sludge discharge is increased to shorten the sludge age in the phosphorus removal area.

[0067] In summary, this method of nitrogen removal and phosphorus removal can control the long sludge age required for nitrogen removal and the short sludge age required for phosphorus removal respectively. It is simple to operate, and the biological nitrogen removal efficiency can reach more than 90%, and the biological phosphorus removal efficiency is between 50% and 70%, which are higher than 80% and 20% of the single activated sludge method or the single biofilm method, thereby improving the sewage treatment efficiency.

[0068] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for simultaneous biological nitrogen and phosphorus removal using MABR, characterized in that: The two parts of the original wastewater are respectively introduced into the denitrification zone and the dephosphorization zone in the sewage treatment system, wherein the amount of wastewater entering the denitrification zone is greater than the amount of wastewater entering the dephosphorization zone; The denitrification zone is provided with a plurality of MABR membrane modules, and the dissolved oxygen concentration in the denitrification zone is monitored to maintain the dissolved oxygen concentration in the denitrification zone at 0.1 mg / L to 0.3 mg / L. When the dissolved oxygen concentration does not meet the requirement, the air supply of the plurality of MABR membrane modules is adjusted, and the effluent of the denitrification zone enters the dephosphorization zone; The dephosphorization zone is provided with an aerator and a flow pusher to monitor the dissolved oxygen concentration in the dephosphorization zone and maintain the dissolved oxygen concentration in the dephosphorization zone at 2mg / L-4mg / L. When the dissolved oxygen concentration does not meet the requirement, the oxygen supply of the aerator is adjusted; The effluent from the dephosphorization zone enters the solid-liquid separation zone, the supernatant from the solid-liquid separation zone is refluxed to the denitrification zone, part of the sludge at the bottom of the solid-liquid separation zone is discharged from the system as residual sludge, and part of it is refluxed to the dephosphorization zone, the sludge reflux ratio is 30% to 50% of the total amount of the wastewater raw water, and the supernatant reflux ratio is 20% to 50% of the total amount of the wastewater raw water; Monitor the total nitrogen concentration of the discharged water from the solid-liquid separation zone, and when the total nitrogen concentration in the discharged water is greater than the required discharge value, increase the proportion of the supernatant refluxed to the denitrification zone; Monitor the total phosphorus concentration of the discharged water from the solid-liquid separation zone, and when the total phosphorus concentration in the discharged water is greater than the discharge requirement value, increase the sludge discharge amount; Monitoring the sludge concentration in the phosphorus removal zone, and controlling the sludge concentration by controlling the sludge return flow; The COD concentration in the phosphorus removal zone is monitored, and the COD / TP in the phosphorus removal zone is ensured to be greater than 17 by adjusting the amount of wastewater raw water entering the phosphorus removal zone.

2. The method for simultaneous biological denitrification and phosphorus removal using MABR according to claim 1, characterized in that: The amount of wastewater entering the denitrification zone is 80-90% of the total amount of the original wastewater, and the amount of wastewater entering the dephosphorization zone is 10-20% of the total amount of the original wastewater.

3. The method for simultaneous biological denitrification and phosphorus removal using MABR according to claim 1, characterized in that: The sewage treatment system includes a MABR membrane tank, an aerobic tank and a solid-liquid separation tank which are interconnected; The MABR membrane pool is the denitrification zone and is provided with a plurality of MABR membrane modules and a first dissolved oxygen monitor inside. The plurality of MABR membrane modules are connected to a gas supply pipeline, and a process gas fan, a process gas flow meter and a process gas regulating valve are sequentially provided on the gas supply pipeline along the air inlet direction; The aerobic tank is the dephosphorization zone, the aerator and the flow pusher are arranged at the bottom of the aerobic tank, the aerator is connected to the aeration pipeline, and the aeration fan, the aeration flow meter and the aeration regulating valve are arranged in sequence along the air inlet direction of the aeration pipeline, and the dephosphorization zone is provided with a second dissolved oxygen monitor and a sludge concentration monitor; An online total nitrogen monitor and an online total phosphorus monitor are provided in the solid-liquid separation tank. The upper part of the solid-liquid separation tank is connected to the MABR membrane tank via a supernatant reflux pipe. A supernatant reflux pump and a supernatant reflux regulating valve are sequentially provided on the supernatant reflux pipe along the water flow direction. A sludge reflux pipe is connected to the bottom of the solid-liquid separation tank. A sludge reflux pump and a reflux sludge regulating valve are sequentially provided on the sludge reflux pipe along the sludge discharge direction. The sludge reflux pipe is also connected to a sludge discharge pipe, and a sludge discharge regulating valve is provided on the sludge discharge pipe.

4. The method for simultaneous biological denitrification and phosphorus removal using MABR according to claim 3, characterized in that: The phosphorus removal area is provided with a COD online monitor.

5. The method for simultaneous biological denitrification and phosphorus removal using MABR according to claim 3, characterized in that: The denitrification zone and the dephosphorization zone are connected to a water inlet pipe, and a raw water regulating valve is provided on the water inlet pipe section connected to the dephosphorization zone.

6. The method for simultaneous biological denitrification and phosphorus removal using MABR according to claim 3, characterized in that: The MABR membrane pool and the aerobic pool are separated by a partition, and a through hole connecting the denitrification zone and the dephosphorization zone is provided at the bottom of the partition.

Images