Anaerobic ammonia oxidation coupled synchronous nitrification and denitrification system based on MBBR (Moving Bed Biofilm Reactor) as well as operation method and application thereof

Abstract

The invention provides an anaerobic ammonia oxidation coupled synchronous nitrification and denitrification system based on an MBBR (moving bed biofilm reactor) and an operation method and application thereof, and relates to the technical field of sewage treatment.The system adjusts the actual carbon-nitrogen ratio of each anoxic tank through segmented water feeding according to the carbon-nitrogen ratio (C / N) of sewage, promotes short-cut denitrification-anaerobic ammonia oxidation and improves the nitrification and denitrification efficiency. Meanwhile, by adjusting dissolved oxygen (DO) of the aerobic tanks, synchronous nitrification and denitrification (SND) and whole-course autotrophic nitrogen removal (CANON) are respectively carried out in the first aerobic tank and the second aerobic tank, so that an anaerobic ammonia oxidation process can be applied to urban sewage treatment; the technical problems that in the prior art, sewage treatment is high in operation cost, large in water quality fluctuation influence, poor in anaerobic ammonia oxidation, high in aeration energy consumption and out-of-standard in effluent ammonia nitrogen are solved, and the technical effects of being excellent in denitrification effect, efficient, capable of saving energy, stable in operation and capable of saving occupied space are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and in particular to an MBBR-based anaerobic ammonia oxidation coupled synchronous nitrification and denitrification system and an operation method and application thereof. Background Art

[0002] In the field of sewage treatment, the traditional nitrification and denitrification process has the characteristics of stable treatment effect and simple operation, and is one of the best treatment processes for high C / N sewage. However, when the C / N of sewage is low, the traditional nitrification and denitrification process requires the addition of a large amount of carbon source to maintain a stable denitrification and denitrification effect, resulting in increased operating costs and sludge production.

[0003] The anaerobic ammonium oxidation process directly produces nitrogen with ammonia nitrogen and nitrite as substrates, without the need for external carbon sources, which can save operating costs and is very suitable for the treatment of low C / N wastewater. According to the source of nitrite, the anaerobic ammonium oxidation process can be divided into short-term nitrification-anaerobic ammonium oxidation (PN-A) and short-term denitrification-anaerobic ammonium oxidation (PD-A).

[0004] In the PN-A process, short-term nitrification oxidizes part of the ammonia nitrogen into nitrite, thereby meeting the influent requirements of the anaerobic ammonium oxidation process (nitrite / ammonia nitrogen = 1.32). There are two process forms based on this principle: one-stage and two-stage. Among them, the one-stage PN-A process can also be called completely autotrophic nitrogen removal over nitrite (CANON). Its short-term nitrification and anaerobic ammonium oxidation reactions occur in the same reactor, which is easier to control than the two-stage PN-A and has a better autotrophic nitrogen removal effect.

[0005] The PD-A process produces nitrite through short-range denitrification, which together with ammonia nitrogen serves as a substrate for anaerobic ammonium oxidation, thereby achieving nitrogen removal. It is suitable for the treatment of municipal sewage, but in actual projects, the influent water quality of sewage treatment plants sometimes fluctuates greatly. When the influent C / N is high, the nitrite produced by PD-A will be further reduced to nitrogen gas, which may limit anaerobic ammonium oxidation. Therefore, relevant measures need to be taken to improve it.

[0006] In the prior art, hydroxylamine is added outside the anoxic tank to promote the activity of short-range denitrifying bacteria and their competitiveness against nitrate, thereby promoting the accumulation of nitrite and the progress of anaerobic ammonium oxidation reaction; however, a large number of studies and practices have shown that microorganisms usually have a certain degree of drug resistance. With the continuous addition of hydroxylamine, the promotion effect on short-range denitrifying bacteria will gradually weaken, and the generated nitrite will gradually decrease. Therefore, it is impossible to maintain a long-term stable short-range denitrification-anaerobic ammonium oxidation reaction; in addition, the addition of hydroxylamine will also increase the cost of sewage treatment and increase the overall operating cost of the sewage treatment plant.

[0007] In the prior art, the anoxic tanks before and after the MBBR system are prompted to achieve PD-A by means of staged water inlet and C / N control, which is beneficial to improving the denitrification efficiency of low C / N wastewater and reducing operating costs. However, it is only limited to the case of low inlet C / N and cannot effectively solve the impact of water quality fluctuations.

[0008] In addition, traditional denitrification reactions often cannot completely remove biodegradable COD, which will enter the aerobic tank and inhibit the nitrification reaction, resulting in waste of aeration energy and excessive ammonia nitrogen in the effluent.

[0009] In view of this, the present invention is proposed. Summary of the invention

[0010] One of the purposes of the present invention is to provide an anaerobic ammonium oxidation coupled synchronous nitrification and denitrification system based on MBBR, which has the characteristics of excellent denitrification effect, high efficiency and energy saving, stable operation and space saving.

[0011] The second object of the present invention is to provide an operation method of an anaerobic ammonium oxidation coupled synchronous nitrification and denitrification system based on MBBR, which can optimize the anaerobic ammonium oxidation effect under different C / N, achieve efficient utilization of biodegradable COD, avoid the inhibition of COD on anaerobic ammonium oxidizing bacteria, and thus promote the maximization of autotrophic nitrogen removal and ensure that the effluent water quality is stable and meets the standards.

[0012] The third object of the present invention is to provide an application of an anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system based on MBBR, which is beneficial to promote the promotion of mainstream anaerobic ammonium oxidation and simultaneous nitrification and denitrification processes in sewage treatment, and is beneficial to the efficient and low-cost treatment of urban sewage.

[0013] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0014] In the first aspect, an anaerobic ammonium oxidation coupled synchronous nitrification and denitrification system based on MBBR includes a biochemical pool, a biochemical pool inlet pipeline, a carbon source addition pipeline, and a biochemical pool outlet pipeline;

[0015] The biochemical pool comprises a first anoxic pool, a second anoxic pool, a third anoxic pool, a first aerobic pool, a second aerobic pool, a third aerobic pool and a fourth anoxic pool which are arranged in sequence;

[0016] The biochemical pool water inlet pipeline is used to distribute sewage to the first anoxic pool, the second anoxic pool, the third anoxic pool and the fourth anoxic pool;

[0017] The carbon source adding pipeline is used for adding the carbon source to the fourth anoxic tank;

[0018] When the sewage C / N is less than 3, the sewage distribution ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 100%, 0%, 0% and 0% respectively, and the C / N of the external carbon source is 2 to 4;

[0019] When the C / N ratio of the sewage is 3-6, the sewage distribution ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 50-100%, 0-30%, 0-10% and 0-15% respectively, and the C / N ratio of the external carbon source is less than 2;

[0020] When the sewage C / N>6, the sewage distribution ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 5-50%, 0-30%, 10-80% and 0-15% respectively, and no carbon source is added.

[0021] Furthermore, a fourth aerobic pool is arranged after the fourth anoxic pool;

[0022] Preferably, the microorganisms of the suspended carrier biofilm in the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are independently denitrifying bacteria and anaerobic ammonia oxidizing bacteria;

[0023] Preferably, the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are each independently provided with an agitator.

[0024] Further, the microorganisms of the suspended carrier biofilm in the first aerobic tank are nitrifying bacteria and denitrifying bacteria, the microorganisms of the suspended carrier biofilm in the second aerobic tank are ammonia oxidizing bacteria and anaerobic ammonia oxidizing bacteria, and the microorganisms of the suspended carrier biofilm in the third aerobic tank and the fourth aerobic tank are independently nitrifying bacteria;

[0025] Preferably, the first aerobic tank, the second aerobic tank, the third aerobic tank and the fourth aerobic tank are each independently provided with an aeration pipeline.

[0026] Furthermore, the porosity of the suspension carrier is ≥90%, and the filling rate is ≤67%.

[0027] Furthermore, the DO of the first aerobic pool is between 1 mg / L and 4 mg / L;

[0028] Preferably, the DO of the second aerobic tank is between 0.2mg / L and 0.5mg / L;

[0029] Preferably, the DO of the third aerobic tank is between 2 mg / L and 8 mg / L;

[0030] Preferably, the DO of the fourth aerobic tank is between 2 mg / L and 8 mg / L.

[0031] Furthermore, the end of the third aerobic tank is connected to the front end of the first anoxic tank through a nitrification liquid return pipeline;

[0032] Preferably, the nitrifying liquid reflux ratio of the nitrifying liquid reflux pipeline is 200% to 400%.

[0033] In a second aspect, a method for operating an anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification system based on MBBR as described in any one of the above items comprises the following steps:

[0034] The sewage is distributed into a first stream of water, a second stream of water, a third stream of water and a fourth stream of water in proportion through the water inlet pipeline of the biochemical pool;

[0035] The first influent, the second influent and the third influent are respectively sent to the first anoxic tank, the second anoxic tank and the third anoxic tank for treatment, the effluent from the third anoxic tank is sequentially sent to the first aerobic tank, the second aerobic tank and the third aerobic tank for treatment, the effluent from the third aerobic tank and the fourth influent are sent to the fourth anoxic tank for treatment together, and the effluent from the fourth anoxic tank is sent to the fourth aerobic tank for treatment.

[0036] Furthermore, the operation method comprises the following steps:

[0037] (a) distributing the sewage into a first influent stream, a second influent stream, a third influent stream and a fourth influent stream in proportion through the influent pipeline of the biochemical pool;

[0038] The first influent, the second influent and the third influent enter the first anoxic tank, the second anoxic tank and the third anoxic tank respectively, and the denitrifying bacteria use the carbon source to perform full denitrification and short-range denitrification to produce nitrogen gas and nitrite respectively, and the nitrite and the ammonia nitrogen in the influent are reduced to nitrogen gas by the anaerobic ammonia-oxidizing bacteria together, and nitrate is produced at the same time;

[0039] (b) The effluent from the third anoxic tank enters the first aerobic tank to perform SND reaction by adjusting DO, using nitrifying bacteria to perform nitrification reaction, and using denitrifying bacteria to perform denitrification, thereby promoting subsequent CANON reaction while utilizing carbon sources;

[0040] (c) The effluent from the first aerobic pool enters the second aerobic pool and performs a CANON reaction by adjusting the DO, using ammonia oxidizing bacteria to perform a short-range nitrification reaction to produce nitrous oxide, which is then reacted with ammonia nitrogen by anaerobic ammonia oxidizing bacteria to complete autotrophic denitrification;

[0041] (d) the effluent from the second aerobic tank enters the third aerobic tank for nitrification reaction to completely oxidize the ammonia nitrogen into nitrate;

[0042] (e) The effluent from the third aerobic pool and the fourth influent enter the fourth anoxic pool together, and the denitrifying bacteria use the raw water carbon source and the external carbon source to perform short-range denitrification to produce nitrite, and the nitrite and the ammonia nitrogen in the influent are reduced to nitrogen gas by the anaerobic ammonia-oxidizing bacteria, and nitrate is produced at the same time, and the denitrifying bacteria use the carbon source to reduce the nitrate to nitrogen gas;

[0043] (f) The effluent from the fourth anoxic pool enters the fourth aerobic pool, where nitrifying bacteria and organic matter oxidizing bacteria remove ammonia nitrogen and COD respectively, ensuring that the effluent ammonia nitrogen and COD stably meet the standards.

[0044] Furthermore, the HRT of the first anoxic pool, the second anoxic pool, the third anoxic pool and the fourth anoxic pool are independently 1 h to 1.5 h;

[0045] Preferably, the HRT of the first aerobic pool and the second aerobic pool are independently 1 h to 1.5 h;

[0046] Preferably, the HRT of the third aerobic tank is 2h to 3h;

[0047] Preferably, the HRT of the fourth aerobic tank is 0.5h to 1h.

[0048] In a third aspect, an anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system based on MBBR as described in any of the above items is used in urban sewage treatment.

[0049] Compared with the prior art, the present invention has at least the following beneficial effects:

[0050] The MBBR-based anaerobic ammonia oxidation coupled synchronous nitrification and denitrification system provided by the present invention can flexibly adjust the C / N of the influent of each anoxic tank by controlling the water distribution ratio and the amount of carbon source added in a manner of segmented water inlet and hierarchical arrangement of the front anoxic tank, thereby realizing the optimization of the anaerobic ammonia oxidation effect under different C / N; at the same time, a synchronous nitrification and denitrification tank is arranged at the front end of the aerobic tank, which can not only realize the efficient utilization of biodegradable COD, but also reduce the inhibition of COD on the reaction of the rear-end tank body; CANON is innovatively placed after the synchronous nitrification and denitrification tank, thereby avoiding the inhibition of COD on the anaerobic ammonia oxidizing bacteria, which is conducive to promoting the maximization of autotrophic denitrification and ensuring that the effluent water quality is stable and meets the standards; in short, the present invention avoids the influence of the fluctuation of the influent water quality on the PD-A and denitrification effect of the system, and also avoids the inhibition of the effluent COD of the anoxic denitrification tank on the aerobic nitrification reaction, thereby achieving the technical effects of excellent denitrification effect, high efficiency and energy saving, stable operation and space saving.

[0051] The operating method of the MBBR-based anaerobic ammonium oxidation coupled synchronous nitrification and denitrification system provided by the present invention can optimize the anaerobic ammonium oxidation effect under different C / N ratios, can achieve efficient utilization of biochemical COD, can avoid the inhibition of COD on anaerobic ammonium oxidizing bacteria, and further promote the maximization of autotrophic nitrogen removal, thereby ensuring that the effluent water quality is stable and meets the standards.

[0052] The application of the MBBR-based anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system provided by the present invention is conducive to promoting the popularization of mainstream anaerobic ammonium oxidation and simultaneous nitrification and denitrification processes in sewage treatment, is conducive to the efficient and low-consumption treatment of urban sewage, and provides a new feasible approach for efficient and low-carbon denitrification of urban sewage. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0054] Figure 1 A schematic diagram of a system for anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification based on MBBR provided in one embodiment of the present invention.

[0055] Icons: 1- main water inlet pipeline; 1.1- first water inlet; 1.2- second water inlet; 1.3- third water inlet; 1.4- fourth water inlet; 2.1- first anoxic tank; 2.2- second anoxic tank; 2.3- third anoxic tank; 2.4- first aerobic tank; 2.5- second aerobic tank; 2.6- third aerobic tank; 2.7- fourth anoxic tank; 2.8- fourth aerobic tank; 2.9- outlet pipeline; 2.10- agitator; 2.11- aeration pipeline; 2.12- nitrification liquid reflux pipeline; 3- carbon source storage tank; 3.1- carbon source addition pipeline. DETAILED DESCRIPTION

[0056] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] According to a first aspect of the present invention, there is provided a MBBR-based anaerobic ammonium oxidation coupled synchronous nitrification and denitrification system, comprising a biochemical pool, a biochemical pool inlet pipeline, a carbon source addition pipeline, and a biochemical pool outlet pipeline;

[0058] The biochemical pool comprises a first anoxic pool, a second anoxic pool, a third anoxic pool, a first aerobic pool, a second aerobic pool, a third aerobic pool and a fourth anoxic pool which are arranged in sequence;

[0059] The biochemical pool water inlet pipeline is used to distribute sewage to the first anoxic pool, the second anoxic pool, the third anoxic pool and the fourth anoxic pool;

[0060] At the same time, the carbon source adding pipeline is used to add the carbon source to the fourth anoxic tank;

[0061] When the sewage C / N is less than 3, the sewage allocation ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 100%, 0%, 0% and 0% respectively, and the external carbon source C / N (external carbon source COD / fourth anoxic tank influent nitrate) can be 2 to 4, for example, 2, 3, 4, but not limited thereto;

[0062] When the sewage C / N is 3-6, the sewage allocation ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 50-100%, 0-30%, 0-10% and 0-15% respectively, and the external carbon source C / N (external carbon source COD / fourth anoxic tank influent nitrate) is less than 2, for example, 2, 1.5, 1, 0.5, but not limited thereto;

[0063] When the sewage C / N>6, the sewage distribution ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 5-50%, 0-30%, 10-80% and 0-15% respectively, and no carbon source is added.

[0064] The MBBR-based anaerobic ammonia oxidation coupled synchronous nitrification and denitrification system provided by the present invention can flexibly adjust the C / N of the inlet water of each anoxic tank by controlling the water distribution ratio and the amount of carbon source added in a manner of segmented water inlet and hierarchical arrangement of the front anoxic tank, thereby realizing the optimization of the anaerobic ammonia oxidation effect under different C / N; at the same time, a synchronous nitrification and denitrification tank is arranged at the front end of the aerobic tank, which can not only realize the efficient utilization of biodegradable COD, but also reduce the inhibition of COD on the reaction of the rear end tank body; CANON is innovatively placed after the synchronous nitrification and denitrification tank, which avoids the inhibition of COD on anaerobic ammonia oxidizing bacteria, is conducive to promoting the maximization of autotrophic nitrogen removal, and ensures that the effluent water quality is stable and meets the standards.

[0065] In summary, the present invention avoids the influence of influent water quality fluctuations on the system PD-A and denitrification effect, and also avoids the inhibition of aerobic nitrification reaction by the effluent COD of the anoxic denitrification tank, thereby achieving the technical effects of excellent denitrification effect, high efficiency and energy saving, stable operation and space saving.

[0066] In a preferred embodiment, a fourth aerobic tank may be arranged after the fourth anoxic tank.

[0067] In the present invention, the first anoxic pool, the second anoxic pool, the third anoxic pool and the fourth anoxic pool are all added with suspended carriers with mature biofilm; the first aerobic pool, the second aerobic pool, the third aerobic pool and the fourth aerobic pool are all added with suspended carriers with mature biofilm.

[0068] In a preferred embodiment, the porosity of the suspension carrier is ≥90%, for example, it can be 90%, 91%, 92%, 93%, 94%, 95%, but not limited to this; the filling rate of the suspension carrier is ≤67%, for example, it can be 67%, 65%, 63%, 61%, 59%, 57%, 55%, 53%, 51%, but not limited to this.

[0069] In a preferred embodiment, the main microorganisms of the suspended carrier biofilm in the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank can independently be denitrifying bacteria and anaerobic ammonia oxidizing bacteria.

[0070] At the same time, the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank can be independently provided with agitators for agitating the sewage so that the sewage can be fully treated.

[0071] In a preferred embodiment, the main microorganisms of the suspended carrier biofilm in the first aerobic tank may be nitrifying bacteria and denitrifying bacteria, and the main microorganisms of the suspended carrier biofilm in the second aerobic tank may be ammonia oxidizing bacteria and anaerobic ammonia oxidizing bacteria; at the same time, the main microorganisms of the suspended carrier biofilm in the third aerobic tank and the fourth aerobic tank may independently be nitrifying bacteria.

[0072] At the same time, the first aerobic pool, the second aerobic pool, the third aerobic pool and the fourth aerobic pool can be independently provided with aeration pipelines, which can adjust the dissolved oxygen content in the water, which is beneficial to maintain the activity of microorganisms and improve the sewage treatment effect.

[0073] In a preferred embodiment, the end of the third aerobic tank can be connected to the front end of the first anoxic tank through a nitrification liquid reflux pipeline; wherein the nitrification liquid reflux ratio of the nitrification liquid reflux pipeline can be 200% to 400%, and its typical but non-limiting reflux ratio is, for example, 200%, 250%, 300%, 350%, and 400%.

[0074] A typical system of anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification based on MBBR, see Figure 1 , including a total water inlet pipeline 1, a biochemical pool, a water outlet pipeline 2.9 and a carbon source addition pipeline 3.1;

[0075] The biochemical pool includes a first anoxic pool 2.1, a second anoxic pool 2.2, a third anoxic pool 2.3, a first aerobic pool 2.4, a second aerobic pool 2.5, a third aerobic pool 2.6, a fourth anoxic pool 2.7 and a fourth aerobic pool 2.8 which are arranged in sequence;

[0076] The first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 are all added with suspended carriers with mature biofilms, and are all provided with agitators 2.10. The main microorganisms of the biofilms of the suspended carriers can be denitrifying bacteria and anaerobic ammonia oxidizing bacteria.

[0077] The first aerobic pool 2.4, the second aerobic pool 2.5, the third aerobic pool 2.6 and the fourth aerobic pool 2.8 are all added with suspended carriers with mature biofilms, and are all provided with aeration pipelines 2.11; the main microorganisms of the suspended carrier biofilm in the first aerobic pool 2.4 may be nitrifying bacteria and denitrifying bacteria, the main microorganisms of the suspended carrier biofilm in the second aerobic pool 2.5 may be ammonia oxidizing bacteria and anaerobic ammonia oxidizing bacteria, and the main microorganisms of the suspended carrier biofilm in the third aerobic pool 2.6 and the fourth aerobic pool 2.8 may both be nitrifying bacteria;

[0078] At the same time, the end of the third aerobic tank 2.6 can be connected to the front end of the first anoxic tank 2.1 through the nitrification liquid return pipeline 2.12;

[0079] The main water inlet pipeline 1 is divided into four water inlets, which are recorded as the first water inlet 1.1, the second water inlet 1.2, the third water inlet 1.3 and the fourth water inlet 1.4, and then the sewage is distributed to the first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 in different proportions according to the water quality of the inlet;

[0080] The carbon source adding pipeline 3.1 is used to add the carbon source in the carbon source storage tank 3 to the fourth anoxic tank 2.7;

[0081] When the sewage C / N is less than 3, the sewage distribution ratios of the first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 are 100%, 0%, 0% and 0% respectively, and the C / N of the external carbon source is 2 to 4;

[0082] When the C / N ratio of the sewage is 3-6, the sewage distribution ratios of the first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 are 50-100%, 0-30%, 0-10% and 0-15% respectively, and the C / N ratio of the external carbon source is less than 2;

[0083] When the sewage C / N>6, the sewage distribution ratios of the first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 are 5-50%, 0-30%, 10-80% and 0-15% respectively, and no carbon source is added.

[0084] On the one hand, the autotrophic denitrification effect of the system of the present invention is good. Through the staged water inlet and the graded arrangement of the front anoxic tank, the actual inlet C / N of the front end of the front anoxic tank is preferentially controlled within the optimal range. The rear anoxic tank is controlled by adjusting the carbon source dosage, which can promote short-range denitrification-anaerobic ammonium oxidation. The CANON tank is arranged after the synchronous nitrification and denitrification tank, which can effectively reduce the restriction of COD on short-range nitrification-anaerobic ammonium oxidation, thereby achieving the optimization of anaerobic ammonium oxidation effect. On the other hand, the system of the present invention has strong resistance to water quality shock. When the inlet C / N When the C / N ratio is low, it is conducive to short-range denitrification-anaerobic ammonium oxidation reaction, and the system mainly undergoes autotrophic denitrification. When the influent C / N ratio is high, the system mainly denitrifies by heterotrophic denitrification, while maintaining the maximum autotrophic denitrification of anaerobic ammonium oxidation, thereby achieving the treatment of sewage with different C / N ratios up to standard. In addition, the system of the present invention has a large energy-saving and consumption-reducing range. Through the optimized regulation of anaerobic ammonium oxidation, the amount of carbon source added can be greatly saved. Anaerobic ammonium oxidation can consume part of the ammonia nitrogen. Simultaneous nitrification and denitrification can remove COD and reduce the aeration volume of the aerobic tank, thereby achieving substantial energy-saving and consumption-reducing.

[0085] In a preferred embodiment, the dissolved oxygen (DO) in the first aerobic tank may be between 1 mg / L and 4 mg / L, and its typical but non-limiting dissolved oxygen is, for example, 1 mg / L, 2 mg / L, 3 mg / L, and 4 mg / L; the dissolved oxygen (DO) in the second aerobic tank may be between 0.2 mg / L and 0.5 mg / L, and its typical but non-limiting dissolved oxygen is, for example, 0.2 mg / L, 0.3 mg / L, 0.4 mg / L, and 0.5 mg / L; the dissolved oxygen in the third aerobic tank may be between 1 mg / L and 4 mg / L, and its typical but non-limiting dissolved oxygen is, for example, 0.5 mg / L, 0.6 mg / L, 0.8 mg / L, 0.9 mg / L, 10 mg / L, 11 mg / L, 12 mg / L, 13 mg / L, 14 mg / L, 15 mg / L, 16 mg / L, 17 mg / L, 18 mg / L, 19 mg / L, 20 mg / L, 21 mg / L, 22 mg / L, 23 mg / L, 24 mg / L, 25 mg / L, 26 mg / L, 27 mg / L, 28 mg / L, 29 mg / L, 30 mg / L, 31 mg / L, 32 mg / L, 34 mg / L, 36 mg / L, 37 mg / L, 38 mg / L, 39 mg / L, 40 mg / L, 41 mg / L, 42 mg / L, 43 mg / L, 44 mg / L, 45 mg / L, 46 mg / L, 47 mg / L, 48 mg / L, 49 mg / L, 50 mg / L, 51 mg / L, 52 mg / L The dissolved oxygen (DO) may be between 2 mg / L and 8 mg / L, and typical but non-limiting examples thereof are 2 mg / L, 3 mg / L, 4 mg / L, 5 mg / L, 6 mg / L, 7 mg / L, and 8 mg / L; the dissolved oxygen (DO) in the fourth aerobic tank may be between 2 mg / L and 8 mg / L, and typical but non-limiting examples thereof are 2 mg / L, 3 mg / L, 4 mg / L, 5 mg / L, 6 mg / L, 7 mg / L, and 8 mg / L.

[0086] According to a second aspect of the present invention, there is provided a method for operating an anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification system based on MBBR as described in any one of the above, comprising the following steps:

[0087] The sewage is distributed into a first stream of water, a second stream of water, a third stream of water and a fourth stream of water in proportion through the water inlet pipeline of the biochemical pool;

[0088] The first influent, the second influent and the third influent are respectively sent to the first anoxic tank, the second anoxic tank and the third anoxic tank for treatment, the effluent from the third anoxic tank is sequentially sent to the first aerobic tank, the second aerobic tank and the third aerobic tank for treatment, the effluent from the third aerobic tank and the fourth influent are sent to the fourth anoxic tank for treatment together, and the effluent from the fourth anoxic tank is sent to the fourth aerobic tank for treatment.

[0089] The operating method of the MBBR-based anaerobic ammonium oxidation coupled synchronous nitrification and denitrification system provided by the present invention can optimize the anaerobic ammonium oxidation effect under different C / N ratios, can achieve efficient utilization of biochemical COD, can avoid the inhibition of COD on anaerobic ammonium oxidizing bacteria, and further promote the maximization of autotrophic nitrogen removal, thereby ensuring that the effluent water quality is stable and meets the standards.

[0090] In a preferred embodiment, the hydraulic retention time (HRT) of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank can independently be 1h to 1.5h, for example, 1h, 1.1h, 1.2h, 1.3h, 1.4h, 1.5h, but not limited thereto.

[0091] In a preferred embodiment, the hydraulic retention time (HRT) of the first aerobic tank and the second aerobic tank can independently be 1 h to 1.5 h, for example, 1 h, 1.1 h, 1.2 h, 1.3 h, 1.4 h, 1.5 h, but not limited thereto.

[0092] In a preferred embodiment, the hydraulic retention time (HRT) of the third aerobic tank can be 2 h to 3 h, for example, 2 h, 2.2 h, 2.4 h, 2.6 h, 2.8 h, 3 h, but not limited thereto.

[0093] In a preferred embodiment, the hydraulic retention time (HRT) of the fourth aerobic tank can be 0.5h to 1h, for example, 0.5h, 0.6h, 0.7h, 0.8h, 0.9h, 1h, but not limited thereto.

[0094] A typical operation method of an MBBR-based anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification system comprises the following steps:

[0095] (a) distributing the sewage into a first influent stream, a second influent stream, a third influent stream and a fourth influent stream in proportion through the influent pipeline of the biochemical pool;

[0096] The first influent, the second influent and the third influent enter the first anoxic tank, the second anoxic tank and the third anoxic tank respectively in different proportions. The denitrifying bacteria on the suspended carrier use the carbon source in the raw water to perform full-range denitrification and short-range denitrification at the same time, thereby producing nitrogen gas and nitrite respectively. The produced nitrite and ammonia nitrogen in the influent are reduced to nitrogen gas together as substrates for anaerobic ammonia-oxidizing bacteria, and a small amount of nitrate is produced at the same time.

[0097] (b) The effluent from the third anoxic tank enters the first aerobic tank and performs simultaneous nitrification and denitrification (SND) by adjusting DO. The outer layer of the suspended carrier nitrifies, and the inner layer of the denitrifying bacteria uses the COD that penetrates the anoxic tank to denitrify, thereby fully utilizing the carbon source of the raw water and promoting the subsequent CANON reaction.

[0098] (c) The effluent from the first aerobic tank enters the second aerobic tank and performs autotrophic denitrification (CANON) by adjusting DO. The ammonia oxidizing bacteria in the outer layer of the suspended carrier undergo short-term nitrification to produce nitrous oxide. Nitrous oxide and ammonia nitrogen serve together as substrates for the anaerobic ammonia oxidizing bacteria in the inner layer to achieve autotrophic denitrification.

[0099] (d) the effluent from the second aerobic tank enters the third aerobic tank for nitrification reaction to completely oxidize the ammonia nitrogen into nitrate;

[0100] (e) The effluent from the third aerobic pool and the fourth influent enter the fourth anoxic pool together. The denitrifying bacteria on the suspended carrier use the raw water and the external carbon source to perform short-range denitrification to produce nitrite. The nitrite and the ammonia nitrogen in the influent are reduced to nitrogen gas as substrates for anaerobic ammonium oxidizing bacteria, and a small amount of nitrate is produced. At the same time, the denitrifying bacteria use the remaining carbon source to reduce the nitrate produced by anaerobic ammonium oxidation to nitrogen gas.

[0101] (f) The effluent from the fourth anoxic pool enters the fourth aerobic pool, where the nitrifying bacteria and organic matter oxidizing bacteria in the suspended carrier remove the remaining ammonia nitrogen and COD respectively, ensuring that the effluent ammonia nitrogen and COD stably meet the standards.

[0102] According to a third aspect of the present invention, there is provided an application of the MBBR-based anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system described in any one of the above in urban sewage treatment.

[0103] The application of the MBBR-based anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system provided by the present invention is conducive to promoting the popularization of mainstream anaerobic ammonium oxidation and simultaneous nitrification and denitrification processes in sewage treatment, is conducive to the efficient and low-consumption treatment of urban sewage, and provides a new feasible approach for efficient and low-carbon denitrification of urban sewage.

[0104] The present invention is further described below by way of examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or directly purchased from the market.

[0105] Example 1

[0106] A MBBR-based anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification system, see Figure 1 , including a total water inlet pipeline 1, a biochemical pool, a water outlet pipeline 2.9 and a carbon source addition pipeline 3.1;

[0107] The biochemical pool includes a first anoxic pool 2.1, a second anoxic pool 2.2, a third anoxic pool 2.3, a first aerobic pool 2.4, a second aerobic pool 2.5, a third aerobic pool 2.6, a fourth anoxic pool 2.7 and a fourth aerobic pool 2.8 which are arranged in sequence;

[0108] The first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 are all added with a suspended carrier with mature biofilm (the porosity of the suspended carrier is 95% and the filling rate is 60%), and are all provided with a stirrer 2.10. The main microorganisms of the suspended carrier biofilm are denitrifying bacteria and anaerobic ammonia oxidizing bacteria;

[0109] The first aerobic pool 2.4, the second aerobic pool 2.5, the third aerobic pool 2.6 and the fourth aerobic pool 2.8 are all added with suspended carriers with mature biofilm (the porosity of the suspended carriers is 95% and the filling rate is 60%), and are all provided with aeration pipelines 2.11; the main microorganisms of the suspended carrier biofilm in the first aerobic pool 2.4 are nitrifying bacteria and denitrifying bacteria, the main microorganisms of the suspended carrier biofilm in the second aerobic pool 2.5 are ammonia oxidizing bacteria and anaerobic ammonia oxidizing bacteria, and the main microorganisms of the suspended carrier biofilm in the third aerobic pool 2.6 and the fourth aerobic pool 2.8 are nitrifying bacteria;

[0110] At the same time, the end of the third aerobic tank 2.6 is connected to the front end of the first anoxic tank 2.1 through the nitrification liquid return pipeline 2.12, and the nitrification liquid return ratio of the nitrification liquid return pipeline 2.12 is 200% to 400%;

[0111] The main water inlet pipeline 1 is divided into a first water inlet 1.1, a second water inlet 1.2, a third water inlet 1.3 and a fourth water inlet 1.4, so that the sewage is distributed to the first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 in different proportions according to the water quality of the inlet water;

[0112] The carbon source adding pipeline 3.1 is used to add the carbon source in the carbon source storage tank 3 to the fourth anoxic tank 2.7;

[0113] When the sewage C / N is less than 3, the sewage distribution ratios of the first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 are 100%, 0%, 0% and 0% respectively, and the C / N of the external carbon source is 2 to 4;

[0114] When the C / N ratio of the sewage is 3-6, the sewage distribution ratios of the first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 are 50-100%, 0-30%, 0-10% and 0-15% respectively, and the C / N ratio of the external carbon source is less than 2;

[0115] When the sewage C / N>6, the sewage distribution ratios of the first anoxic tank 2.1, the second anoxic tank 2.2, the third anoxic tank 2.3 and the fourth anoxic tank 2.7 are 5-50%, 0-30%, 10-80% and 0-15% respectively, and no carbon source is added.

[0116] Example 2

[0117] The difference between this embodiment and embodiment 1 is that the nitrification liquid return pipeline 2.12 is not provided in the system of this embodiment, that is, the end of the third aerobic tank 2.6 is not connected to the front end of the first anoxic tank 2.1;

[0118] The rest are the same as in Example 1.

[0119] Compared with Example 1, the defect of the system of this embodiment is that the first anoxic tank 2.1, the second anoxic tank 2.2 and the third anoxic tank 2.3 cannot perform short-range denitrification and anaerobic ammonia oxidation due to the lack of nitrate, resulting in a waste of raw water carbon source; at the same time, the amount of external carbon source added to the fourth anoxic tank 2.7 will increase, and the aeration volume of each aerobic tank will increase.

[0120] Example 3

[0121] The only difference between this embodiment and embodiment 1 is that in this embodiment, the fourth aerobic pool 2.8 is not provided after the fourth anoxic pool 2.7 in the system;

[0122] The rest are the same as in Example 1.

[0123] Compared with Example 1, the defect of the system of this embodiment is that the ammonia nitrogen and COD in the system effluent are significantly higher than those in Example 1, and there is a great risk of exceeding the standard.

[0124] Example 4

[0125] This embodiment is an operation method of the system of embodiment 1, comprising the following steps:

[0126] (a) distributing the sewage into a first influent stream, a second influent stream, a third influent stream and a fourth influent stream in proportion through the influent pipeline of the biochemical pool;

[0127] The first influent, the second influent and the third influent enter the first anoxic tank, the second anoxic tank and the third anoxic tank respectively in different proportions. The denitrifying bacteria on the suspended carrier use the carbon source in the raw water to perform full-range denitrification and short-range denitrification at the same time, thereby producing nitrogen gas and nitrite respectively. The produced nitrite and ammonia nitrogen in the influent are reduced to nitrogen gas together as substrates for anaerobic ammonia-oxidizing bacteria, and a small amount of nitrate is produced at the same time.

[0128] (b) The effluent from the third anoxic tank enters the first aerobic tank and performs simultaneous nitrification and denitrification (SND) by adjusting DO. The outer layer of the suspended carrier nitrifies, and the inner layer of the denitrifying bacteria uses the COD that penetrates the anoxic tank to denitrify, thereby fully utilizing the carbon source of the raw water and promoting the subsequent CANON reaction.

[0129] (c) The effluent from the first aerobic tank enters the second aerobic tank and performs autotrophic denitrification (CANON) by adjusting DO. The ammonia oxidizing bacteria in the outer layer of the suspended carrier undergo short-term nitrification to produce nitrous oxide. Nitrous oxide and ammonia nitrogen serve together as substrates for the anaerobic ammonia oxidizing bacteria in the inner layer to achieve autotrophic denitrification.

[0130] (d) the effluent from the second aerobic tank enters the third aerobic tank for nitrification reaction to completely oxidize the ammonia nitrogen into nitrate;

[0131] (e) The effluent from the third aerobic pool and the fourth influent enter the fourth anoxic pool together. The denitrifying bacteria on the suspended carrier use the raw water and the external carbon source to perform short-range denitrification to produce nitrite. The nitrite and the ammonia nitrogen in the influent are reduced to nitrogen gas as substrates for anaerobic ammonium oxidizing bacteria, and a small amount of nitrate is produced. At the same time, the denitrifying bacteria use the remaining carbon source to reduce the nitrate produced by anaerobic ammonium oxidation to nitrogen gas.

[0132] (f) The effluent from the fourth anoxic pool enters the fourth aerobic pool, where the nitrifying bacteria and organic matter oxidizing bacteria in the suspended carrier remove the remaining ammonia nitrogen and COD respectively, ensuring that the effluent ammonia nitrogen and COD stably meet the standards.

[0133] Comparative Example 1

[0134] The difference between this comparative example and Example 1 is that the fourth anoxic pool 2.7 is not provided in the system of this comparative example;

[0135] The rest are the same as in Example 1.

[0136] Compared with Example 1, the defect of this comparative example system is that the total nitrogen in the effluent of the third aerobic tank 2.6 cannot be further removed, resulting in a significant increase in the total nitrogen in the effluent compared with Example 1, which can be increased by up to about 10 mg / L.

[0137] Comparative Example 2

[0138] The difference between this comparative example and Example 1 is that the first aerobic tank 2.4 is not provided in the system of this comparative example;

[0139] The rest are the same as in Example 1.

[0140] Compared with Example 1, the defect of this comparative example system is that the biodegradable organic matter in the effluent of the third anoxic tank 2.3 directly enters the second aerobic tank 2.5, resulting in a waste of raw water carbon source and inhibiting the CANON effect of the second aerobic tank 2.5. The total nitrogen in the effluent of the third aerobic tank 2.6 will increase by more than 4.8 mg / L, and the carbon source dosage in the fourth anoxic tank 2.7 will increase by more than 8.6 mg COD / L.

[0141] Comparative Example 3

[0142] The difference between this comparative example and Example 1 is that the second aerobic tank 2.5 is not provided in the system of this comparative example;

[0143] The rest are the same as in Example 1.

[0144] Compared with Example 1, the defects of this comparative example system are that the total nitrogen in the effluent of the third aerobic tank 2.6 will increase by about 5.4 mg / L, and the amount of carbon source added in the fourth anoxic tank 2.7 will increase by about 9.6 mg COD / L.

[0145] Test Example 1

[0146] The system of Example 1 was tested for sewage treatment. The system operation method was referred to Example 4. The inlet and outlet water qualities are shown in Table 1.

[0147] The system operating parameters are as follows:

[0148] Average influent COD, NH4 + -N and TN were 140.67 mg / L, 46.99 mg / L and 49.16 mg / L respectively, and the influent C / N was only 2.86;

[0149] The water flow rate is 210m 3 / d, the HRT of the first, second, third and fourth anoxic pools is 1.0h, the HRT of the first, second, third and fourth aerobic pools is 1.0h, 1.0h, 2.0h and 0.5h respectively, totaling 8.5h;

[0150] The influent completely enters the first anoxic tank, that is, the influent ratios of the first, second, third and fourth anoxic tanks are 100%, 0%, 0% and 0% respectively, and the internal recirculation ratio is 300%; the dissolved oxygen of the first, second, third and fourth aerobic tanks are 1.5 mg / L, 0.2 mg / L, 4.0 mg / L and 4.0 mg / L respectively;

[0151] The amount of external carbon source added to the fourth anoxic pool was 32.5 mg / L, and the C / N ratio of the external carbon source was 3.29.

[0152] After the system is running stably, the TN of the system effluent can be reduced to about 2.68 mg / L, and the total nitrogen removal is calculated to be 46.49 mg / L. The short-range denitrification-anaerobic ammonium oxidation (PD-A) denitrification accounts for 18.76%, 9.47% and 5.44% in the first, second and third anoxic tanks respectively, and the short-range nitrification-anaerobic ammonium oxidation (PN-A) in the second aerobic tank accounts for 10.32%, totaling 43.98%; the synchronous nitrification and denitrification denitrification in the first aerobic tank accounts for 7.03%.

[0153] Table 1 Inlet and outlet water quality (low inlet C / N)

[0154] CODcr <![CDATA[NH4 + -N]]> TN Water Intake 140.67±8.98 46.99±2.37 49.16±2.71 Water 38.92±1.50 0.05±0.11 2.68±0.65

[0155] Test Example 2

[0156] The system of Example 1 was tested for sewage treatment. The system operation method was referred to Example 4. The inlet and outlet water qualities are shown in Table 2.

[0157] The system operating parameters are as follows:

[0158] Average influent COD, NH4 + -N and TN were 260.58 mg / L, 51.62 mg / L and 52.62 mg / L, respectively, and the influent C / N was 4.95;

[0159] The water flow rate is 175m 3 / d, the HRT of the first, second, third and fourth anoxic pools were all 1.2 h, and the HRT of the first, second, third and fourth aerobic pools were 1.2 h, 1.2 h, 2.4 h and 0.6 h, respectively, for a total of 10.2 h;

[0160] The water distribution ratios of the first, second, third and fourth anoxic pools are 70%, 15%, 5% and 10% respectively, and the internal reflow ratio is 250%; the dissolved oxygen of the first, second, third and fourth aerobic pools are 2.0mg / L, 0.3mg / L, 4.5mg / L and 5.0mg / L respectively;

[0161] The amount of external carbon source added to the fourth anoxic pool was 17.0 mg / L, and the C / N ratio of the external carbon source was 1.79.

[0162] After the system is running stably, the TN of the system effluent can be reduced to about 4.67 mg / L, and the total nitrogen removal is calculated to be 47.95 mg / L. The short-range denitrification-anaerobic ammonium oxidation (PD-A) denitrification accounts for 16.30%, 5.64%, 2.62% and 12.26% in the first, second, third and fourth anoxic tanks respectively, and the short-range nitrification-anaerobic ammonium oxidation (PN-A) in the second aerobic tank accounts for 11.25%, totaling 46.91%; the synchronous nitrification and denitrification denitrification in the first aerobic tank accounts for 10.09%.

[0163] Table 2 Inlet and outlet water quality (normal inlet C / N)

[0164] CODcr <![CDATA[NH4 + -N]]> TN Water Intake 260.58±6.05 51.62±1.07 52.62±1.09 Water 39.51±0.64 0.06±0.11 4.67±0.45

[0165] Test Example 3

[0166] The system of Example 1 was tested for sewage treatment. The system operation method was referred to Example 4. The inlet and outlet water qualities are shown in Table 3.

[0167] The system operating parameters are as follows:

[0168] Average influent COD, NH4 + -N and TN were 433.59 mg / L, 53.99 mg / L and 55.05 mg / L respectively, and the influent C / N was as high as 7.88;

[0169] The water flow rate is 140m 3 / d, the HRT of the first, second, third and fourth anoxic pools are all 1.5h, and the HRT of the first, second, third and fourth aerobic pools are 1.5h, 1.3h, 2.5h and 0.7h, respectively, for a total of 12.0h;

[0170] The water distribution ratios of the first, second, third and fourth anoxic pools are 30%, 5%, 55% and 10% respectively, and the internal reflow ratio is 320%; the dissolved oxygen of the first, second, third and fourth aerobic pools are 3.0mg / L, 0.4mg / L, 6.0mg / L and 6.0mg / L respectively;

[0171] No external carbon source is added to the fourth anoxic pool.

[0172] After the system is running stably, the TN of the system effluent can be reduced to about 4.25 mg / L, and the total nitrogen removal is calculated to be 50.80 mg / L. The short-range denitrification-anaerobic ammonium oxidation (PD-A) denitrification accounts for 13.94%, 2.57%, 0.10% and 12.17% in the first, second, third and fourth anoxic tanks, respectively, and the short-range nitrification-anaerobic ammonium oxidation (PN-A) in the second aerobic tank accounts for 9.45%, totaling 38.22%, successfully realizing the anaerobic ammonium oxidation reaction under high influent C / N conditions; the simultaneous nitrification and denitrification denitrification in the first aerobic tank accounts for 12.21%.

[0173] Table 3 Inlet and outlet water quality (high inlet C / N)

[0174] CODcr <![CDATA[NH4 + -N]]> TN Water Intake 433.59±11.10 53.99±1.16 55.05±1.17 Water 39.82±0.79 0.02±0.05 4.25±0.21

[0175] It can be seen that the present invention flexibly adjusts the C / N of the inlet water of each anoxic tank by controlling the water distribution ratio and the amount of carbon source added through the way of segmented water inlet and graded arrangement of the front anoxic tank, so as to achieve the optimization of the anaerobic ammonia oxidation effect under different C / N; at the same time, a synchronous nitrification and denitrification tank is arranged at the front end of the aerobic tank, which can not only achieve the efficient utilization of biodegradable COD, but also reduce the inhibition of COD on the reaction of the rear end tank body; CANON is innovatively placed after the synchronous nitrification and denitrification tank, which avoids the inhibition of COD on anaerobic ammonia oxidizing bacteria, is conducive to promoting the maximization of autotrophic denitrification, and ensures that the effluent water quality is stable and meets the standards.

[0176] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification system based on MBBR, characterized in that: It includes a biochemical pool, a water inlet pipeline for the biochemical pool, a carbon source adding pipeline, and a water outlet pipeline for the biochemical pool; The biochemical pool comprises a first anoxic pool, a second anoxic pool, a third anoxic pool, a first aerobic pool, a second aerobic pool, a third aerobic pool and a fourth anoxic pool which are arranged in sequence; The biochemical pool water inlet pipeline is used to distribute sewage to the first anoxic pool, the second anoxic pool, the third anoxic pool and the fourth anoxic pool; The carbon source adding pipeline is used for adding the carbon source to the fourth anoxic tank; When the sewage C / N is less than 3, the sewage distribution ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 100%, 0%, 0% and 0% respectively, and the C / N of the external carbon source is 2 to 4; When the C / N ratio of the sewage is 3-6, the sewage distribution ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 50-100%, 0-30%, 0-10% and 0-15% respectively, and the C / N ratio of the external carbon source is less than 2; When the sewage C / N>6, the sewage distribution ratios of the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are 5-50%, 0-30%, 10-80% and 0-15% respectively, and no carbon source is added.

2. The MBBR-based anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system according to claim 1, characterized in that: A fourth aerobic pool is arranged behind the fourth anoxic pool; Preferably, the microorganisms of the suspended carrier biofilm in the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are independently denitrifying bacteria and anaerobic ammonia oxidizing bacteria; Preferably, the first anoxic tank, the second anoxic tank, the third anoxic tank and the fourth anoxic tank are each independently provided with an agitator.

3. The MBBR-based anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system according to claim 2, characterized in that: The microorganisms of the suspended carrier biofilm in the first aerobic tank are nitrifying bacteria and denitrifying bacteria, the microorganisms of the suspended carrier biofilm in the second aerobic tank are ammonia oxidizing bacteria and anaerobic ammonia oxidizing bacteria, and the microorganisms of the suspended carrier biofilm in the third aerobic tank and the fourth aerobic tank are independently nitrifying bacteria; Preferably, the first aerobic tank, the second aerobic tank, the third aerobic tank and the fourth aerobic tank are each independently provided with an aeration pipeline.

4. The MBBR-based anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system according to claim 3, characterized in that: The porosity of the suspension carrier is ≥90%, and the filling rate is ≤67%.

5. The MBBR-based anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification system according to any one of claims 1 to 4, characterized in that: The DO of the first aerobic pool is between 1 mg / L and 4 mg / L; Preferably, the DO of the second aerobic tank is between 0.2mg / L and 0.5mg / L; Preferably, the DO of the third aerobic tank is between 2 mg / L and 8 mg / L; Preferably, the DO of the fourth aerobic tank is between 2 mg / L and 8 mg / L.

6. The MBBR-based anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification system according to any one of claims 1 to 4, characterized in that: The end of the third aerobic tank is connected to the front end of the first anoxic tank through a nitrification liquid reflux pipeline; Preferably, the nitrifying liquid reflux ratio of the nitrifying liquid reflux pipeline is 200% to 400%.

7. A method for operating an anaerobic ammonium oxidation coupled with simultaneous nitrification and denitrification system based on MBBR according to any one of claims 1 to 6, characterized in that: The following steps are involved: The sewage is distributed into a first stream of water, a second stream of water, a third stream of water and a fourth stream of water in proportion through the water inlet pipeline of the biochemical pool; The first influent, the second influent and the third influent are respectively sent to the first anoxic tank, the second anoxic tank and the third anoxic tank for treatment, the effluent from the third anoxic tank is sequentially sent to the first aerobic tank, the second aerobic tank and the third aerobic tank for treatment, the effluent from the third aerobic tank and the fourth influent are sent to the fourth anoxic tank for treatment together, and the effluent from the fourth anoxic tank is sent to the fourth aerobic tank for treatment.

8. The operating method according to claim 7, characterized in that: The operation method comprises the following steps: (a) distributing the sewage into a first influent stream, a second influent stream, a third influent stream and a fourth influent stream in proportion through the influent pipeline of the biochemical pool; The first influent, the second influent and the third influent enter the first anoxic tank, the second anoxic tank and the third anoxic tank respectively, and the denitrifying bacteria use the carbon source to perform full denitrification and short-range denitrification to produce nitrogen gas and nitrite respectively, and the nitrite and the ammonia nitrogen in the influent are reduced to nitrogen gas by the anaerobic ammonia-oxidizing bacteria together, and nitrate is produced at the same time; (b) The effluent from the third anoxic tank enters the first aerobic tank to perform SND reaction by adjusting DO, using nitrifying bacteria to perform nitrification reaction, and using denitrifying bacteria to perform denitrification, thereby promoting subsequent CANON reaction while utilizing carbon sources; (c) The effluent from the first aerobic pool enters the second aerobic pool and performs a CANON reaction by adjusting the DO, using ammonia oxidizing bacteria to perform a short-range nitrification reaction to produce nitrous oxide, which is then reacted with ammonia nitrogen by anaerobic ammonia oxidizing bacteria to complete autotrophic denitrification; (d) the effluent from the second aerobic tank enters the third aerobic tank for nitrification reaction to completely oxidize the ammonia nitrogen into nitrate; (e) The effluent from the third aerobic pool and the fourth influent enter the fourth anoxic pool together, and the denitrifying bacteria use the raw water carbon source and the external carbon source to perform short-range denitrification to produce nitrite, and the nitrite and the ammonia nitrogen in the influent are reduced to nitrogen gas by the anaerobic ammonia-oxidizing bacteria, and nitrate is produced at the same time, and the denitrifying bacteria use the carbon source to reduce the nitrate to nitrogen gas; (f) The effluent from the fourth anoxic pool enters the fourth aerobic pool, where nitrifying bacteria and organic matter oxidizing bacteria remove ammonia nitrogen and COD respectively, ensuring that the effluent ammonia nitrogen and COD stably meet the standards.

9. The operating method according to claim 7 or 8, characterized in that: The HRT of the first anoxic pool, the second anoxic pool, the third anoxic pool and the fourth anoxic pool are independently 1 h to 1.5 h; Preferably, the HRT of the first aerobic pool and the second aerobic pool are independently 1 h to 1.5 h; Preferably, the HRT of the third aerobic tank is 2h to 3h; Preferably, the HRT of the fourth aerobic tank is 0.5h to 1h.

10. Application of the MBBR-based anaerobic ammonium oxidation coupled simultaneous nitrification and denitrification system according to any one of claims 1 to 6 in urban sewage treatment.

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