Ammonia nitrogen wastewater treatment system and method based on Donnan dialysis and MABR

Abstract

The invention provides an ammonia nitrogen wastewater treatment system and method based on Donnan dialysis and MABR, which organically combine Donnan dialysis and PN / A-MABR, utilize Donnan dialysis technology to separate ammonia nitrogen from organic matter in ammonia nitrogen-containing wastewater, enrich ammonia nitrogen in a driving solution, and use a MABR reactor to achieve denitrification and regeneration of the driving solution through PN / A technology, so as to effectively avoid the adverse effects of organic matter on the PN / A system; utilize the salinity of the driving solution to inhibit the activity of NOB in the MABR, so as to achieve a nitrification process dominated by short-range nitrification; and utilize an aerated membrane to maintain the aerobic short nitrification process only in the biofilm on the membrane surface, while the reactor body is still in an anaerobic environment, so as to ensure the efficient realization of PN / A in a single reactor.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and in particular to an ammonia nitrogen wastewater treatment system and method based on Donnan dialysis and MABR. Background Art

[0002] Ammonia nitrogen is an important cause of black and smelly water bodies. Deep denitrification of sewage and wastewater is crucial to protecting the ecological environment and ensuring water quality safety. Anaerobic ammonia oxidation (Anammox) refers to the process in which anaerobic ammonia oxidizing bacteria use NO 2 - As electron acceptor, NH 4 + or NH 3 Oxidation to N 2 The denitrification processes formed by the process of nitrification / anaerobic ammonium oxidation (PN / A) and the short-range denitrification / anaerobic ammonium oxidation (PD / A) processes include. Among them, compared with the traditional nitrification / denitrification process, the PN / A process can save 60% of aeration energy consumption, 100% of organic carbon source consumption, and 90% of residual sludge production, and has significant economic and environmental benefits. At present, when using the PN / A process to treat nitrogen-containing wastewater, there are the following problems: (1) Short-range nitrification regulation is difficult, the NOB (nitrite oxidizing bacteria) in the system is highly active, and nitrite is quickly converted into nitrate, so the PN / A process cannot be effectively established; (2) Anaerobic ammonium oxidizing bacteria are anaerobic microorganisms, and AOB (ammonia oxidizing bacteria) are aerobic microorganisms. The contradiction in the regulation of dissolved oxygen restricts the realization of the PN / A process in a single reactor; (3) Anaerobic ammonium oxidizing bacteria are autotrophic bacteria. The widespread presence of organic matter in actual wastewater will inhibit the activity of anaerobic ammonium oxidizing bacteria. Summary of the invention

[0003] In view of this, the present invention aims to propose an ammonia nitrogen wastewater treatment system and method based on Donnan dialysis and MABR.

[0004] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0005] An ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR, comprising a water inlet tank, a Donnan dialysis reactor, a driving liquid tank and a MABR reactor;

[0006] A feed liquid chamber and a driving liquid chamber are provided inside the Donnan dialysis reactor, the feed liquid chamber and the driving liquid chamber are separated by a cation exchange membrane, the feed liquid chamber is connected to a water inlet tank via a feed liquid inlet and a feed liquid circulation port via a pipeline, and the driving liquid chamber is connected to a driving liquid tank via a driving liquid inlet and a driving liquid circulation port via a pipeline, the liquid flows in the feed liquid chamber and the driving liquid chamber in opposite directions, and liquid circulation is achieved by a peristaltic pump;

[0007] The MABR reactor is provided with a water inlet, a water outlet, two internal reflux ports and an aeration membrane assembly. The water inlet and the water outlet are connected to the driving liquid tank via pipelines, and the two internal reflux ports are connected via a peristaltic pump to achieve mud-water mixing in the reactor; the air inlet of the aeration membrane assembly is connected to the aeration pump via a pipeline, and the air outlet is connected to the outside of the reactor via a pipeline and is controlled by a regulating valve.

[0008] Furthermore, the cationic exchange membrane is a homogeneous cation exchange membrane or a heterogeneous cation exchange membrane.

[0009] Furthermore, the aeration membrane in the aeration membrane assembly is a microporous hollow fiber aeration membrane or a non-porous hollow fiber aeration membrane.

[0010] Furthermore, the material of the microporous hollow fiber aeration membrane is PVDF, PTFE or PE, and the membrane pore size is 0.01-0.2 μm; the material of the non-porous hollow fiber aeration membrane is non-porous silicone rubber.

[0011] The present invention also provides a method for treating ammonia nitrogen wastewater based on Donnan dialysis and MABR, which utilizes the above-mentioned ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR to perform denitrification, and the method comprises the following steps:

[0012] 1) Film formation

[0013] Take the activated sludge from the urban sewage treatment plant in the MABR reactor and add NH 4 The driving liquid of Cl is used as the influent of MABR reactor, and it is continuously aerated until nitrite is the dominant form of nitrate nitrogen in the system and obvious biofilm is formed on the membrane surface to complete biofilm formation; ammonium chloride is added to provide ammonia nitrogen and cultivate nitrifying bacteria;

[0014] 2) Inoculation of anaerobic ammonium oxidizing bacteria:

[0015] The muddy water in the MABR reactor was poured out to add NH 4 The driving liquid of Cl is used as the influent of MABR reactor, and the anaerobic ammonia-oxidizing bacteria granular sludge is inoculated. The aeration pressure of the aeration membrane module is adjusted to maintain aerobic conditions only on the membrane surface, and the process is operated until efficient and stable denitrification is achieved, completing the construction of PN / A process.

[0016] 3) Fill the water inlet tank with wastewater containing ammonia nitrogen, and fill the driving liquid tank with driving liquid;

[0017] 4) Turn on all pumps to separate ammonia nitrogen from organic matter in the wastewater through the Donnan dialysis reactor, and enrich ammonia nitrogen in the driving liquid. The driving liquid then enters the MABR reactor, and the driving liquid is denitrified and regenerated through the PN / A technology, effectively avoiding the adverse effects of organic matter on the PN / A system, and using the salinity of the driving liquid to inhibit the activity of NOB in the MABR, to achieve a nitrification process dominated by short-term nitrification; part of the ammonia nitrogen in the MABR reactor is oxidized to nitrite by the ammonia-oxidizing bacterial biofilm on the surface of the aeration membrane, and the generated nitrite and the remaining ammonia nitrogen are then used by the anaerobic ammonia-oxidizing bacteria in the MABR to produce nitrogen and a small amount of nitrate, completing the denitrification process; the use of aeration membrane allows the aerobic short-term nitrification process to be maintained only in the biofilm on the membrane surface, while the reactor body remains in an anaerobic environment, ensuring the efficient realization of PN / A in a single reactor; the driving liquid after denitrification is circulated back to the driving liquid tank.

[0018] Furthermore, in step 1), the aeration conditions are as follows: the aeration pressure of the aeration membrane assembly is adjusted so that the dissolved oxygen in the reactor is maintained at 0.5-1.5 mg / L, and the residence time is 6 h-24 h.

[0019] Furthermore, in step 2), the dissolved oxygen in the MABR reactor is maintained at 0.01 mg / L to 0.5 mg / L, and the residence time is 6 h to 24 h.

[0020] Furthermore, the concentration of the driving liquid is 3-15 g / L, and the driving liquid loaded into the driving liquid tank is NaCl solution or NaHCO 3 Solution or NaCl and NaHCO 3 of mixed salt solution.

[0021] The present invention also provides an application of the above-mentioned ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR in the treatment of ammonia nitrogen-containing wastewater with a low carbon-nitrogen ratio.

[0022] Compared with the prior art, the ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR described in the present invention has the following advantages:

[0023] 1. Donnan dialysis is used to enrich ammonia nitrogen from ammonia nitrogen wastewater, realizing the separation of organic matter and ammonia nitrogen, avoiding the inhibition of organic matter on anaerobic ammonia-oxidizing bacteria and adverse effects on the PN / A system; and the separate treatment of organic matter and ammonia nitrogen improves the flexibility of wastewater treatment system operation and control.

[0024] 2. The driving solution composed of salt can inhibit NOB activity and solve the problem of difficult-to-control short-range nitrification.

[0025] 3. In MABR, the heterogeneous mass transfer characteristics of the aeration membrane are used to achieve dissolved oxygen control, regulate the aerobic environment of the surface biofilm and the anaerobic environment of the reactor body, thereby realizing the PN / A process in one reactor.

[0026] 4. The efficient denitrification of MABR realizes the effective regeneration of the driving liquid in the Donnan dialysis reactor, so that the driving force of ammonia nitrogen transmembrane mass transfer is maintained at a high level.

[0027] 5. The ammonia nitrogen wastewater treatment system and method based on Donnan dialysis and MABR described in the present invention organically combines Donnan dialysis and PN / A-MABR, and has the advantages of low energy consumption, high denitrification efficiency, convenient and flexible control, good stability, etc., and can achieve efficient denitrification of ammonia nitrogen-containing wastewater with a low carbon-nitrogen ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0029] Figure 1 This is a schematic diagram of the structure of the ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR described in Example 1 of the present invention;

[0030] Figure 2 This is a treatment effect diagram of the ammonia nitrogen wastewater treatment method based on Donnan dialysis and MABR described in Example 2 of the present invention;

[0031] Figure 3 This is the effect diagram of ammonia nitrogen wastewater treatment in Comparative Example 1;

[0032] Figure 4 This is the effect diagram of ammonia nitrogen wastewater treatment in Comparative Example 2;

[0033] Figure 5 This is the effect diagram of ammonia nitrogen wastewater treatment in Comparative Example 3;

[0034] Figure 6 This is a diagram showing the effect of ammonia nitrogen wastewater treatment in Comparative Example 4;

[0035] Figure 7 This is the effect diagram of ammonia nitrogen wastewater treatment in comparative example 5.

[0036] Description of reference numerals:

[0037] 1. Water inlet tank; 2. Peristaltic pump; 3. Flow meter; 4. Donnan dialysis reactor; 4-1. Feed liquid chamber; 4-2. Cation exchange membrane; 4-3. Drive liquid chamber; 5. Drive liquid tank; 6. MABR reactor; 6-1. Water inlet; 6-2. Aeration membrane assembly; 6-3. Water outlet; 6-4. Internal reflux port; 6-5. Air inlet; 6-6. Air outlet; 6-7. Regulating valve; 7. Aeration pump; 8. Pressure gauge. DETAILED DESCRIPTION

[0038] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0039] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not 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.

[0042] Example 1 Ammonia nitrogen wastewater treatment system

[0043] like Figure 1As shown, an ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR includes a water inlet tank 1, a Donnan dialysis reactor 4, a driving liquid tank 5 and a MABR reactor 6;

[0044] A feed liquid chamber 4-1 and a driving liquid chamber 4-3 are provided inside the Donnan dialysis reactor 4, the feed liquid chamber and the driving liquid chamber 4-3 are separated by a cation exchange membrane 4-2, the feed liquid chamber 4-1 is connected to the water inlet tank 1 via a feed liquid inlet and a feed liquid circulation port via a pipeline, and the driving liquid chamber 4-3 is connected to the driving liquid tank 5 via a pipeline via a driving liquid inlet and a driving liquid circulation port, and the liquid flows in the feed liquid chamber 4-1 and the driving liquid chamber 4-3 in opposite directions, and liquid circulation is achieved by a peristaltic pump 2; the peristaltic pump 2 is arranged on a pipeline connected to the feed liquid inlet and a pipeline connected to the driving liquid inlet, and a flow meter 3 is also arranged on the pipeline;

[0045] The MABR reactor 6 is provided with a water inlet 6-1, a water outlet 6-3, two internal reflux ports 6-4, and an aeration membrane assembly 6-2; the water inlet and the water outlet are connected to the driving liquid tank 5 via pipelines, and a peristaltic pump and a flow meter are also provided on each pipeline connecting the water inlet and the water outlet; the two internal reflux ports are connected by a peristaltic pump 2 to achieve mud-water mixing in the reactor, the air inlet 6-5 of the aeration membrane assembly is connected to the aeration pump 7 through a pipeline, and the air outlet 6-6 is connected to the outside of the reactor through a pipeline, and is controlled by a regulating valve 6-7.

[0046] A pressure gauge 8 and a flow meter are also provided on the pipeline connected to the aeration pump 7 .

[0047] Exemplarily, the cationic exchange membrane is a homogeneous cation exchange membrane 4-2 or a heterogeneous cation exchange membrane 4-2.

[0048] Exemplarily, the aeration membrane in the aeration membrane assembly is a microporous hollow fiber aeration membrane or a non-porous hollow fiber aeration membrane.

[0049] For example, the material of the microporous hollow fiber aeration membrane is PVDF, PTFE or PE, and the membrane pore size is 0.01-0.2 μm; the material of the non-porous hollow fiber aeration membrane is non-porous silicone rubber.

[0050] Specifically, in this embodiment, the total volume of the Donnan dialysis reactor is 2.1 L, of which the volume of the feed liquid chamber is 0.9 L, the volume of the driving liquid chamber is 1.2 L, and the total effective area of ​​the cation exchange membrane is 0.57 m 2 The driving solution is NaCl solution with a concentration of 6 g / L.

[0051] The total volume of the MABR reactor is 3L. The aeration membrane is a PVDF microporous hollow fiber aeration membrane with a pore size of 0.2μm. The membrane area of ​​the module is 0.3 m 2 .

[0052] Example 2 Ammonia nitrogen wastewater treatment method

[0053] The ammonia nitrogen wastewater treatment method based on Donnan dialysis and MABR, the method uses the ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR described in Example 1 to denitrify, the method comprises the following steps:

[0054] 1) Film formation

[0055] Take 3000 mg / L of activated sludge from a municipal sewage treatment plant and place it in a MABR reactor. Add NH 4 Cl was added to make the ammonia concentration 100 mg N / L as the influent of MABR. The hydraulic retention time was controlled to 24h, and the aeration pressure of the aeration membrane was adjusted to maintain the dissolved oxygen in the reactor at 1.5 mg / L. After two months of operation, nitrite was the dominant form of nitrate nitrogen in the system, and a clear biofilm was formed on the membrane surface.

[0056] 2) Inoculation of anaerobic ammonium oxidizing bacteria:

[0057] Pour out the muddy water in the MABR to add NH 4 Cl and NaCl mixed solution was used as MABR influent, with ammonia concentration of 100 mg N / L and NaCl concentration of 6 g / L. 4000 mg / L of anaerobic ammonia oxidizing bacteria granular sludge was inoculated into the reactor, and the aeration pressure of the aeration membrane was adjusted to maintain the dissolved oxygen in the MABR below 0.5 mg / L. The hydraulic retention time was 24 h. After two months of operation, the total nitrogen removal rate of the system could be maintained above 70%, completing the PN / A process construction.

[0058] 3) The water inlet tank is filled with simulated low carbon-nitrogen ratio ammonia nitrogen-containing wastewater, in which the COD concentration is 200 mg / L and the ammonia nitrogen concentration is 100 mgN / L, and the driving liquid tank is filled with NaCl driving liquid with a concentration of 6 g / L.

[0059] 4) Turn on the peristaltic pumps and air pumps to control the dissolved oxygen in the MABR below 0.5 mg / L.

[0060] The wastewater is separated from ammonia nitrogen and organic matter by the Donnan dialysis reactor 4, and the ammonia nitrogen is enriched in the driving liquid. The driving liquid then enters the MABR reactor and is denitrified and regenerated by the PN / A technology. Part of the ammonia nitrogen in the MABR reactor is oxidized to nitrite by the ammonia oxidizing bacteria biofilm on the surface of the aeration membrane, and the generated nitrite and the remaining ammonia nitrogen are then used by the anaerobic ammonia oxidizing bacteria in the MABR to produce nitrogen gas and a small amount of nitrate, completing the denitrification process. The denitrified driving liquid is circulated back to the driving liquid tank 5.

[0061] Monitor the changes of ammonia nitrogen concentration in the feed liquid and MABR over time. The results are as follows Figure 2 As shown, the removal rate of ammonia nitrogen in the wastewater to be treated reached more than 90% after 24 hours.

[0062] Comparative Example 1

[0063] The same MABR reactor as in Example 2 was used to treat the ammonia nitrogen-containing wastewater, but it was not used in conjunction with the Donnan dialysis reactor.

[0064] The water inlet and outlet of the MABR reactor are connected to the water inlet tank via pipelines, and other connection methods of the MABR reactor are the same as those in Example 1.

[0065] Monitor the changes of ammonia nitrogen concentration in the feed liquid and MABR over time. Figure 3 As shown in the figure, due to the limitation of low dissolved oxygen concentration in MABR, the nitrification process of ammonia nitrogen is not sufficient; the organic matter in the influent also inhibits the activity of anaerobic ammonia-oxidizing bacteria, further limiting the removal effect of total nitrogen in the system, with a removal rate of only 31%.

[0066] Comparative Example 2

[0067] Compared with Example 2, no driving liquid is used, that is, no driving liquid is added to the driving liquid tank, which is only used as a transfer tank. The concentration of ammonia nitrogen in the feed liquid and MABR is monitored over time. Figure 4 As shown in Figure 2, the absence of a driving solution greatly reduces the driving force for ammonia nitrogen to pass through the ion exchange membrane. Although MABR still has a high removal efficiency for ammonia nitrogen that migrates to the driving solution, the lower driving force leads to a significant reduction in the efficiency of wastewater ammonia nitrogen treatment.

[0068] Comparative Example 3

[0069] Compared with Example 2, when the concentration of the drive solution is 2 g / L, the concentration of ammonia nitrogen in the monitored feed solution and MABR changes over time as shown in Figure 5 As shown in the figure, as the concentration of the driving liquid decreases, the driving force for ammonia nitrogen to pass through the ion exchange membrane decreases, and the system's treatment efficiency for ammonia nitrogen in wastewater decreases.

[0070] Comparative Example 4

[0071] Compared with Example 2, when the concentration of the drive solution was 17 g / L, the concentration of ammonia nitrogen in the monitored feed solution and MABR changed with time as shown in Figure 6 As shown in the figure, as the concentration of the driving solution increases, the initial driving force of ammonia nitrogen passing through the ion exchange membrane increases, but the high concentration of the driving solution significantly reduces the activity of microorganisms in the MABR, the nitrification and anaerobic ammonia oxidation processes in the MABR are significantly inhibited, and the ammonia nitrogen concentration in the MABR increases.

[0072] Comparative Example 5

[0073] Compared with Example 2, the driving solution is Na2 SO 4 Solution, concentration is 6g / L. Monitor the change of ammonia nitrogen concentration in feed solution and MABR over time. Figure 7 shown. Na 2 SO 4 As a driving liquid, the activity of the MABR biological system was significantly inhibited, resulting in a significant increase in the ammonia nitrogen concentration in the MABR system compared with Example 2.

[0074] Therefore, the ammonia nitrogen wastewater treatment system and method based on Donnan dialysis and MABR described in the present invention have the advantages of low energy consumption, high denitrification efficiency, convenient and flexible control, good stability, etc., and can achieve efficient denitrification of ammonia nitrogen-containing wastewater with a low carbon-nitrogen ratio.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR, characterized by: It includes the water inlet tank, Donnan dialysis reactor, drive liquid tank and MABR reactor; A feed liquid chamber and a driving liquid chamber are provided inside the Donnan dialysis reactor, the feed liquid chamber and the driving liquid chamber are separated by a cation exchange membrane, the feed liquid chamber is connected to a water inlet tank via a feed liquid inlet and a feed liquid circulation port via a pipeline, and the driving liquid chamber is connected to a driving liquid tank via a driving liquid inlet and a driving liquid circulation port via a pipeline, the liquid flows in the feed liquid chamber and the driving liquid chamber in opposite directions, and liquid circulation is achieved by a peristaltic pump; The MABR reactor is provided with a water inlet, a water outlet, two internal reflux ports and an aeration membrane assembly. The water inlet and the water outlet are connected to the driving liquid tank via pipelines, and the two internal reflux ports are connected by a peristaltic pump to achieve mud-water mixing in the reactor; the air inlet of the aeration membrane assembly is connected to the aeration pump through a pipeline, and the air outlet is connected to the outside of the reactor through a pipeline and controlled by a regulating valve; the MABR reactor is a PN / A-MABR reactor, which completes the PN / A process construction in the reactor, and realizes denitrification and regeneration of the driving liquid through PN / A technology.

2. The ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR according to claim 1 is characterized in that: The cationic exchange membrane is a homogeneous cation exchange membrane or a heterogeneous cation exchange membrane.

3. The ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR according to claim 1 is characterized in that: The aeration membrane in the aeration membrane assembly is a microporous hollow fiber aeration membrane or a non-porous hollow fiber aeration membrane.

4. The ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR according to claim 3 is characterized in that: The material of the microporous hollow fiber aeration membrane is PVDF, PTFE or PE, and the membrane pore size is 0.01~0.2μm; the material of the non-porous hollow fiber aeration membrane is non-porous silicone rubber.

5. A method for treating ammonia nitrogen wastewater based on Donnan dialysis and MABR, characterized in that: The method utilizes the ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR as described in any one of claims 1 to 4 for denitrification, and the method comprises the following steps: 1) Film formation: Take the activated sludge from the urban sewage treatment plant and place it in the MABR reactor. Use the driving liquid with NH4Cl added as the MABR reactor inlet water. Aerate continuously until nitrite is the dominant form of nitrate nitrogen in the system and obvious biofilm is formed on the membrane surface, completing biofilm formation. 2) Inoculation of anaerobic ammonium oxidizing bacteria: The muddy water in the MABR reactor was poured out, and the driving liquid with NH4Cl added was used as the MABR reactor inlet water. The anaerobic ammonia-oxidizing bacteria granular sludge was inoculated, and the aeration pressure of the aeration membrane module was adjusted to maintain aerobic conditions only on the membrane surface, completing the PN / A process construction; 3) Fill the water inlet tank with wastewater containing ammonia nitrogen, and fill the driving liquid tank with driving liquid; 4) Turn on all pumps to separate ammonia nitrogen from organic matter in the wastewater through the Donnan dialysis reactor, and enrich ammonia nitrogen in the driving liquid. The driving liquid then enters the MABR reactor, and the PN / A technology is used to achieve denitrification and regeneration of the driving liquid. The salinity of the driving liquid is used to inhibit the activity of NOB in the MABR, and a nitrification process dominated by short-range nitrification is achieved; part of the ammonia nitrogen in the MABR reactor is oxidized to nitrite by the ammonia-oxidizing bacterial biofilm on the surface of the aeration membrane, and the generated nitrite and the remaining ammonia nitrogen are then used by the anaerobic ammonia-oxidizing bacteria in the MABR to produce nitrogen gas and a small amount of nitrate, completing the denitrification process; the driving liquid after denitrification is circulated back to the driving liquid tank.

6. The method for treating ammonia nitrogen wastewater based on Donnan dialysis and MABR according to claim 5, characterized in that: In step 1), the aeration conditions are as follows: the aeration pressure of the aeration membrane assembly is adjusted so that the dissolved oxygen in the reactor is maintained at 0.5-1.5 mg / L, and the residence time is 6 h-24 h.

7. The method for treating ammonia nitrogen wastewater based on Donnan dialysis and MABR according to claim 5, characterized in that: In step 2), the dissolved oxygen in the MABR reactor is maintained at 0.01 mg / L~0.5 mg / L, and the residence time is 6h~24h.

8. The method for treating ammonia nitrogen wastewater based on Donnan dialysis and MABR according to claim 5, characterized in that: The concentration of the driving liquid is 3-15 g / L, and the driving liquid loaded into the driving liquid tank is a NaCl solution or a NaHCO3 solution or a mixed salt solution of NaCl and NaHCO3.

9. Application of the ammonia nitrogen wastewater treatment system based on Donnan dialysis and MABR as described in any one of claims 1 to 4 in the treatment of ammonia nitrogen-containing wastewater with a low carbon-nitrogen ratio.

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