A method and application for enhancing anaerobic ammonium oxidation performance by stimulating cell membrane stress.

Abstract

This invention discloses a method and application for improving anaerobic ammonia oxidation performance based on stimulating cell membrane stress, relating to the field of water treatment technology. This method utilizes a pulsed dosing mode to add a membrane-forming agent to trigger the membrane stress of anaerobic ammonia-oxidizing bacteria. Continuous addition of the agent leads to severe sludge buoyancy, while the pulsed dosing mode allows time to balance the lipid removal rate of the agent and the lipid synthesis rate of the anaerobic ammonia-oxidizing cells, ultimately improving anaerobic ammonia oxidation performance and enhancing denitrification efficiency. This method is suitable for wastewater treatment facilities that cannot provide sufficient mixing intensity or have dead zones, using chemical stimulation to partially replace mechanical stirring, avoiding the inefficiency and instability of the anaerobic ammonia oxidation process, and can be widely applied.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, and more specifically, to a method and application for improving the performance of anaerobic ammonia oxidation based on stimulating cell membrane stress. Background Technology

[0002] Anaerobic ammonia oxidation (AMO) is widely considered a promising biological nitrogen removal method with good treatment performance and cost-effectiveness (Mishra et al., 2022). However, the presence of poorly mixed zones / dead zones in wastewater treatment facilities leads to reduced mass transfer, thus limiting the nitrogen removal efficiency of AMO bacteria. Triggering cell membrane stress can enhance the nitrogen metabolism pathway of AMO bacteria, thereby partially compensating for the problems caused by insufficient mixing in the reactor. Membrane stress is a bacterial stress state caused by external pressure or adverse environmental conditions, which can affect intracellular material transport and metabolic capacity, and regulate cell growth and metabolic activity (Mitchell & Silhavy, 2019). How to enable AMO bacteria to adapt well to and utilize limited substrates under conditions of insufficient wastewater mixing, and effectively improve nitrogen removal efficiency, is a pressing technical challenge in this field.

[0003] In view of this, the present invention is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a method and application for improving anaerobic ammonia oxidation performance based on stimulating cell membrane stress, so as to solve the above-mentioned technical problems.

[0005] This invention is implemented as follows:

[0006] In a first aspect, embodiments of the present invention provide a method for enhancing anaerobic ammonia oxidation performance based on stimulating cell membrane stress, comprising: adding a membrane-coating agent to wastewater in a pulsed mode to carry out an anaerobic ammonia oxidation reaction; wherein the membrane-coating agent is selected from at least one of β-cyclodextrin, procaine and dipyridamole.

[0007] Secondly, embodiments of the present invention provide an application of the aforementioned method in anaerobic ammonia oxidation treatment of wastewater.

[0008] The present invention has the following beneficial effects:

[0009] This invention provides a method for enhancing anaerobic ammonia oxidation performance based on stimulating cell membrane stress. The method includes: adding a membrane-forming agent to wastewater in a pulsed mode to induce an anaerobic ammonia oxidation reaction; using the membrane-forming agent to trigger the membrane stress of anaerobic ammonia oxidizing bacteria; and the pulsed addition of the membrane-forming agent allows time to balance the lipid removal rate of β-cyclodextrin and the lipid synthesis rate of anaerobic ammonia oxidizing cells, ultimately improving anaerobic ammonia oxidation performance. This method enhances the activity of anaerobic ammonia oxidizing bacteria and improves denitrification efficiency. This method is suitable when wastewater treatment facilities cannot provide sufficient mixing intensity or dead zones exist, using chemical stimulation to partially replace mechanical stirring, avoiding the inefficiency and instability of the anaerobic ammonia oxidation process, and can be widely promoted. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 Records of coating reagent additions during the test period, where the arrow indicates the addition of 600 μM coating reagent once per day;

[0012] Figure 2 Nitrogen concentrations in the influent and effluent of the anaerobic ammonia oxidation reactor: the treatment effect without adding coating reagent for the first 20 days, and the treatment effect with pulsed addition of coating reagent after 20 days;

[0013] Figure 3 A schematic diagram of an apparatus for improving the performance of anaerobic ammonia oxidation by adding a coating reagent;

[0014] Figure 4 This is a schematic diagram showing the denitrification effect test results of Examples 1-3 and Comparative Examples 1-2.

[0015] Icons: 1-Inlet regulating tank; 2-Electric gate; 3-First water pump; 4-Coated reagent dosing device; 5-Magnetic stirring tank; 6-Magnetic stirring rotor; 7-Touch display screen; 8-Coated reagent sample addition tank; 9-Second water pump; 10-Anaerobic ammonia oxidation reaction tank; 11-Mechanical stirrer. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0017] This invention enhances the permeability of biofilms by adding a coating agent, inducing a coating stress response. This allows anaerobic ammonia-oxidizing bacteria to adapt and utilize limited substrates even under conditions of insufficient wastewater mixing, effectively improving nitrogen removal efficiency.

[0018] In a first aspect, the present invention provides a method for enhancing anaerobic ammonia oxidation performance based on stimulating cell membrane stress, comprising: adding a coating agent to wastewater in a pulsed mode to carry out an anaerobic ammonia oxidation reaction; wherein the coating agent is selected from at least one of β-cyclodextrin, procaine and dipyridamole.

[0019] It should be noted that the coating agent is an amphiphilic substance. By triggering the cell's coating stress, it can enhance the nitrogen metabolism pathway of anaerobic ammonia-oxidizing bacteria, thereby partially compensating for the problems caused by insufficient mixing in the reactor.

[0020] β-Cyclodextrin is an organic compound that exists as a white powder or crystal. Because it is a heptasaccharide that can be extracted from glucose, it is easy to produce and inexpensive. β-Cyclodextrin is water-soluble, non-hygroscopic, but readily forms stable hydrates. Furthermore, β-Cyclodextrin is also valued for its low toxicity (LD50 < 12500 mg / kg). -1 It is classified as an environmentally friendly chemical because it is biodegradable (at acute oral doses in rats and mice) and is suitable for engineered applications.

[0021] Procaine exists as white crystals or crystalline powder, is readily soluble in water, has low toxicity, and can disrupt cell membrane dynamics by blocking ion channel proteins.

[0022] Dipyridamole is a yellow crystalline powder, commonly used as a phosphodiesterase inhibitor, indicating that it can interact with cell membranes.

[0023] In an optional embodiment of the present invention, the coating agent includes β-cyclodextrin.

[0024] In an optional embodiment of the present invention, the pulse mode includes the addition of the coating agent at least once every 24 hours.

[0025] It should be noted that the pulse mode is a periodic operation and stop-start pattern. That is, the addition is stopped when the anammox effect continues to improve, and it is resumed when the treatment effect deteriorates. The addition frequency can be dynamically adjusted according to the anammox denitrification effect. In addition, the control of the coating reagent addition frequency is to avoid a large number of anammox particles floating to the surface, and also to test whether a good treatment effect can be maintained when the addition is intermittent.

[0026] Specifically, the interval for adding the coating reagent in pulse mode is at least 24 hours. For example, the interval can be selected from 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 8 days, 10 days, 15 days, 18 days, 20 days, or other reasonable times. In other embodiments of the present invention, the interval can be reasonably adjusted according to the actual amount of wastewater treated and the concentration of the coating reagent used.

[0027] In an optional embodiment of the present invention, the coating agent is further dissolved before being added to the wastewater. The concentration of the coating agent solution is 580 μM-610 μM, preferably 600 μM.

[0028] Specifically, a central controller is used to precisely control the coating reagent, and the nitrogen concentration in the water is quantitatively analyzed during the dissolution process of the coating reagent to optimize and determine the appropriate dosage and frequency of β-cyclodextrin. The dosage of β-cyclodextrin powder is aimed at activating the cell membrane stress response in anammox, and this objective is achieved when the β-cyclodextrin concentration in the anammox reactor 10 reaches 600 μM.

[0029] It should be noted that the coating reagent can be stirred appropriately during the dissolution process to ensure it is fully dissolved in the water; the concentration of β-cyclodextrin needs to be determined manually by sampling. The specific dosage of β-cyclodextrin is related to the amount of wastewater being treated and can be adjusted appropriately based on the actual situation.

[0030] In an optional embodiment of the present invention, the denitrification efficiency of wastewater after the addition of the coating agent is 67.4% ± 4.8%.

[0031] It should be noted that the calculation of denitrification efficiency requires manual sampling and quantitative analysis of nitrogen concentration in the water. Furthermore, it can optimize and determine the appropriate dosage and frequency of the coating reagent.

[0032] In an optional embodiment of the present invention, the cycle of the sequential batch operation is 10h-13h, and the exchange rate is 50%; further, the cycle of the sequential batch operation is 12h.

[0033] In an optional embodiment of the present invention, the anaerobic ammonia oxidation is carried out in a sequencing batch process, which includes an influent stage, a reaction stage, a sedimentation stage, and a drainage stage; wherein the influent stage lasts for 3 min to 6 min, the reaction stage lasts for 11 h to 12 h, the sedimentation stage lasts for 18 min to 22 min, and the drainage stage lasts for 4 min to 6 min.

[0034] It should be noted that by precisely controlling the time and conditions of each stage, the optimal effect of each step can be ensured; the fine control of each stage makes the effluent water quality more stable and reliable; by adjusting the time allocation of each stage, it is possible to better adapt to different changes in influent water quality and quantity; and by optimizing the operating cycle, unnecessary energy consumption and equipment operating time are reduced, thereby reducing operating costs.

[0035] Furthermore, the anaerobic ammonia oxidation reaction using a sequencing batch reactor (SBR) has the following advantages: the ideal plug flow process increases the driving force of the biochemical reaction, improves efficiency, and results in good purification; the operation is stable; the presence of retained treated water in the reaction tank dilutes and buffers the wastewater, effectively resisting the impact of water volume and organic pollutants; each step in the process can be adjusted according to water quality and quantity, making operation flexible; in addition, the SBR requires relatively few treatment devices, has a simple structure, and is easy to operate and maintain; the process flow is simple, the SBR occupies a small area, and is inexpensive.

[0036] The process consists of several stages: the influent stage introduces wastewater into the reactor to prepare for subsequent treatment; the reaction stage removes inorganic nitrogen from the water through anaerobic ammonia oxidation; the sedimentation stage uses gravity to separate sludge and water for subsequent drainage; and the drainage stage discharges the treated water, completing one treatment cycle.

[0037] In an optional embodiment of the present invention, the batch processing mode includes a settling stage after the drainage stage. Its main function is to separate the sediment and sludge-water mixture to improve the effluent quality and sludge concentration, which is beneficial for subsequent treatment or resource utilization, and enhances the overall treatment efficiency and stability of the system. During this stage, suspended solids in the mixed liquor settle under gravity, thereby achieving sludge-water separation.

[0038] Furthermore, the water intake stage lasts for 5 minutes, the reaction stage lasts for 11.5 hours, the sedimentation stage lasts for 20 minutes, and the drainage stage lasts for 5 minutes.

[0039] In an optional embodiment of the present invention, the solution in the anaerobic ammonia oxidation reactor 10 is stirred, which is beneficial to the mixing of the solution within a certain range, and the stirring speed and time can be set according to the actual water quality of the influent and effluent.

[0040] In an optional embodiment of the present invention, the device for adding a coating reagent to enhance the performance of anaerobic ammonia oxidation includes an influent conditioning tank 1, a coating reagent dispenser 4, and an anaerobic ammonia oxidation reaction tank 10, as detailed below. Figure 3 .

[0041] The outlet of the inlet regulating tank 1 is connected to the inlet of the coating reagent dosing device 4, and an electric gate 2 and a first water pump 3 are connected at the outlet of the inlet regulating tank 1. Sewage first enters the inlet regulating tank 1, and the collected sewage is pumped into the coating reagent dosing device 4 through the electric gate 2 and the first water pump 3.

[0042] The coating reagent dispenser 4 is equipped with a magnetic stirring tank 5, a touch screen 7, a central controller and a coating reagent sample tank 8. A magnetic stirring rotor 6 is also installed inside the magnetic stirring tank 5. The coating reagent dispenser 4 releases the coating reagent powder and makes it fully dissolved in the wastewater through magnetic stirring. The wastewater is pumped into the anaerobic ammonia oxidation reaction tank 10 by the second water pump 9.

[0043] Specifically, the touch screen 7 is connected to the central controller, which can precisely control the weight and frequency of sample addition. During operation, the required powder mass of the coating reagent to be added is preset via the touch screen 7, and the central controller will control the coating reagent dispensing slot 8 to open and release the coating reagent powder. Then, the magnetic stirring rotor 6 in the magnetic stirring tank 5 rotates, quickly mixing and fully dissolving the coating reagent.

[0044] It should be noted that the embodiments of the present invention do not impose special limitations on the specifications and models of the first water pump 3 and the second water pump 9. They can be selected from ordinary water pumps with simple structure and function or integrated multi-functional water pumps according to actual needs.

[0045] The outlet of the coating reagent dosing device 4 is connected to the inlet of the anaerobic ammonia oxidation reactor 10. The material from the coating reagent dosing device 4 is pumped into the anaerobic ammonia oxidation reactor 10 via the second water pump 9 for reaction. The anaerobic ammonia oxidation reactor 10 is connected to a mechanical stirrer 11; the mechanical stirrer 11 can provide mixing for a certain range of liquids, and its speed and stirring time can be set according to the influent and effluent water quality. The anaerobic ammonia oxidation reaction is carried out for a certain period while the mechanical stirrer 11 is on to remove ammonia nitrogen and nitrite nitrogen from the water. The effectively denitrified wastewater is discharged through the electric gate 2.

[0046] It should be noted that the anaerobic ammonia oxidation reactor 10 operates in a sequencing batch process, with each cycle lasting 12 hours, an exchange rate of 50%, and a hydraulic retention time of approximately 24 hours. This setup ensures that the anaerobic ammonia oxidizing bacteria are in full contact with the wastewater, maximizing the removal of ammonia nitrogen and nitrite nitrogen from the wastewater.

[0047] In summary, the working principle of the device for enhancing anaerobic ammonium oxidation performance by adding a coating reagent is as follows:

[0048] Wastewater first collects in the influent equalization tank 1, then enters the coating reagent dosing device 4 through the electric gate 2 and the first water pump 3. The dosing parameters are set according to the touch screen 7, adjusting the dosing mass and frequency of the coating reagent powder. The powder is fully dissolved in the magnetically stirred water tank 5. Subsequently, the wastewater is pumped into the anaerobic ammonia oxidation reactor 10 via the second water pump 9. The anaerobic ammonia oxidizing bacteria experience coating stress caused by the coating reagent, stimulating and strengthening their nitrogen metabolism pathways, thereby improving biological nitrogen removal efficiency. With an exchange rate of 50% and a hydraulic retention time of approximately 24 hours, sufficient contact between the anaerobic ammonia oxidizing bacteria and the wastewater is ensured, maximizing the removal of ammonia nitrogen and nitrite nitrogen from the wastewater.

[0049] Secondly, embodiments of the present invention provide an application of the aforementioned method in anaerobic ammonia oxidation treatment of wastewater.

[0050] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0051] Example 1

[0052] This embodiment provides a method for enhancing anaerobic ammonium oxidation performance based on stimulating cell membrane stress, which includes the following steps:

[0053] (1) The wastewater collected in the influent equalization tank 1 is mainstream (low concentration) municipal wastewater that has undergone partial nitrification, characterized by an ammonia nitrogen concentration of 50 mg / L. -1 The concentration of nitrite nitrogen was 66 mg / L. -1 pH range 7-8, dissolved oxygen below 0.1 mg / L -1 The dosage is 1L.

[0054] (2) The coating reagent used is β-cyclodextrin. The coating reagent dispenser 4 adds β-cyclodextrin powder to the magnetically stirred water tank 5 in pulse mode to control the concentration of β-cyclodextrin in the water at 600 μM. During this period, the magnetic stirrer is turned on to ensure that the β-cyclodextrin is fully dissolved in the water.

[0055] In this embodiment, the amount of β-cyclodextrin powder added accounts for 0.068% of the amount of wastewater used for treatment.

[0056] Specific application frequency as follows Figure 1 As shown: the intervals from left to right are 4, 4, 6, 8, 4, 18, 6, 5, 6, 4, 5, 8, 6, 4 days.

[0057] (3) The anaerobic ammonia oxidation reactor 10 operates in a sequencing batch reactor (SBR) mode, with each cycle lasting 12 hours. This includes a 5-minute influent stage, an 11.5-hour reaction stage, a 20-minute sedimentation stage, and a 5-minute effluent stage. The exchange rate is 50%, and the hydraulic retention time is approximately 24 hours to ensure sufficient contact between the anaerobic ammonia oxidizing bacteria and the wastewater, maximizing the removal of ammonia nitrogen and nitrite nitrogen. The mechanical stirring speed is 40 rpm, and the sludge concentration (VSS, volatile suspended solids) is 0.93 g / L. -1 .

[0058] (4) After adding β-cyclodextrin to the water six times, the ammonia nitrogen concentration in the effluent decreased to 1.4 mg / L. -1 The nitrite nitrogen concentration in the effluent was 8.5 mg / L. -1 The total inorganic nitrogen concentration was 33.4 mg / L. -1 The nitrogen removal efficiency reached 72.4%. The effect of adding β-cyclodextrin on anaerobic ammonium oxidation throughout the entire experimental period is shown in [reference needed]. Figure 2 As shown.

[0059] Example 2

[0060] This embodiment provides a method for enhancing anaerobic ammonium oxidation performance based on stimulating cell membrane stress, which includes the following steps:

[0061] (1) Add mainstream (low concentration) urban sewage to the serum bottle, characterized by an ammonia nitrogen concentration of 50 mg / L. -1 The concentration of nitrite nitrogen was 66 mg / L. -1 pH range 7-8, dissolved oxygen below 0.1 mg / L -1 The dosage is 100mL.

[0062] (2) β-Cyclodextrin was selected as the coating agent. The coating agent was directly dissolved in the influent water and thoroughly stirred to control the concentration of β-cyclodextrin in the water at 600 μM. In this embodiment, the amount of β-cyclodextrin powder added accounted for 0.068% of the total amount of wastewater treated.

[0063] (3) After placing the serum bottle on a shaker at 120 rpm and reacting at 30°C for 24 hours, the concentrations of ammonia nitrogen and nitrite nitrogen in the water were determined. The residual ammonia nitrogen concentration in the water was below the detection limit (<0.025 mg / L). -1 The remaining nitrite nitrogen concentration was 4.1 mg / L. -1 ±2.8mg L -1 The effect of adding β-cyclodextrin on anaerobic ammonium oxidation during the experimental period of this batch is shown in [reference needed]. Figure 4 As shown.

[0064] Example 3

[0065] This embodiment provides a method for enhancing anaerobic ammonium oxidation performance based on stimulating cell membrane stress, which differs from Embodiment 2 only in that:

[0066] (2) Procaine was selected as the coating agent, and the concentration of procaine in the water was controlled at 600 μM. In this embodiment, the amount of procaine powder added accounted for 0.013% of the amount of wastewater treated.

[0067] (3) The ammonia nitrogen concentration in the water in this embodiment is 10.8 mg / L. -1 ±0.6mg L -1 The remaining nitrite nitrogen concentration was 28.9 mg / L. -1 ±1.9mg L -1 The effect of procaine addition on anaerobic ammonium oxidation during the experimental period for this batch is shown in [reference needed]. Figure 4 As shown.

[0068] Example 4

[0069] This embodiment provides a method for enhancing anaerobic ammonium oxidation performance based on stimulating cell membrane stress, which differs from Embodiment 2 only in that:

[0070] (2) The coating agent used was dipyridamole, and the concentration of dipyridamole in the water was controlled at 600 μM. In this embodiment, the amount of dipyridamole powder added accounted for 0.030% of the amount of wastewater treated.

[0071] (3) The residual ammonia nitrogen concentration in the water in this embodiment is 0.4 mg / L. -1 ±0.3mg L -1 The remaining nitrite nitrogen concentration was 17.9 mg / L. -1 ±0.8mg L -1 The effect of adding dipyridamole on anaerobic ammonium oxidation during the experimental period of this batch is shown in [reference needed]. Figure 4 As shown.

[0072] It should be noted that Examples 2-4 are short-term batch experiments of the coating reagent to screen the optimal coating reagent for stimulating cell membrane stress and improving anaerobic ammonia oxidation performance; while Example 1 is a long-term experiment using β-cyclodextrin.

[0073] Comparative Example 1

[0074] This comparative example provides a method for enhancing anaerobic ammonium oxidation performance based on stimulating cell membrane stress, which differs from Example 1 only in that:

[0075] Missing (2), that is, no coating agent was used;

[0076] (3) The sludge concentration VSS (volatile suspended solids) was 0.93 g / L. -1 .

[0077] (4) The ammonia nitrogen concentration in the effluent was 31.2 mg / L. -1 The nitrite nitrogen concentration in the effluent was 10.8 mg / L. -1 The average concentration of total inorganic nitrogen was 62.6 mg / L. -1 The nitrogen removal efficiency reached 49.0%.

[0078] Comparative Example 2

[0079] This comparative example provides a method for enhancing anaerobic ammonium oxidation performance based on stimulating cell membrane stress, which differs from Example 1 only in that:

[0080] (2) The coating reagent dispenser 4 continuously adds β-cyclodextrin powder to the magnetically stirred water tank 5;

[0081] (3) The sludge concentration VSS (volatile suspended solids) was 0.93 g / L. -1 .

[0082] (4) The ammonia nitrogen concentration in the effluent was 48.6 mg / L. -1 ±1.1mg L -1 The nitrite nitrogen concentration in the effluent was 65.4 mg / L. -1 ±1.3mg L -1 The average concentration of total inorganic nitrogen was 114 mg / L. -1 ±1.3mg L -1 The nitrogen removal efficiency reached 1.7%.

[0083] Experimental Example 1

[0084] This experiment tested the denitrification effect in Examples 1-3 and Comparative Examples 1-2. The tested parameters included effluent ammonia nitrogen concentration, effluent nitrite nitrogen concentration, average total inorganic nitrogen concentration, and denitrification efficiency. The effluent ammonia nitrogen concentration was tested using Nessler's reagent spectrophotometry, and the effluent nitrite nitrogen concentration was tested using N-(1-naphthyl)-ethylenediamine spectrophotometry. A summary of the relevant results can be found in [link to relevant results]. Figure 4 .

[0085] The formula for calculating the average concentration of total inorganic nitrogen is as follows: Average concentration of total inorganic nitrogen = effluent nitrite nitrogen + effluent ammonia nitrogen + effluent nitrate nitrogen;

[0086] The formula for calculating the denitrification efficiency is as follows: Denitrification efficiency = (Influent nitrite nitrogen + Influent ammonia nitrogen - Effluent total inorganic nitrogen) / (Influent nitrite nitrogen + Influent ammonia nitrogen).

[0087] Combination Figure 2 and Figure 4It can be seen that procaine has a negative impact on denitrification, reducing the removal of ammonia nitrogen and nitrite nitrogen by anaerobic ammonia oxidizing bacteria; dipyridamole showed no statistically significant difference compared with the control group (i.e., the group without added coating reagent), and had no effect on denitrification; while β-cyclodextrin significantly promoted the removal of ammonia nitrogen and nitrite nitrogen by anaerobic ammonia oxidation. The long-term validation test results of Example 1 showed that adding 600 μM β-cyclodextrin in pulse mode significantly reduced the effluent nitrogen concentration, especially from days 36 to 73, with the effluent ammonia nitrogen concentration as low as 1.4 mg / L. -1 -6.6mg L -1 During this period, the average concentration of total inorganic nitrogen in the effluent was 39.6 mg / L. -1 ±5.9mg L -1 The denitrification efficiency reached 67.7% ± 4.5%; however, the continuous addition of β-cyclodextrin caused the stability of sludge microorganisms to be destroyed and they gradually died. It was observed that the sludge gradually turned black, and the anaerobic ammonia oxidation treatment effect decreased significantly.

[0088] In summary, the method for improving anaerobic ammonia oxidation performance provided by this invention utilizes a pulsed dosing mode to add β-cyclodextrin, triggering the membrane stress of anaerobic ammonia oxidizing bacteria. Continuous addition of β-cyclodextrin leads to severe sludge buoyancy, while the pulsed dosing mode allows time to balance the lipid removal rate of β-cyclodextrin and the lipid synthesis rate of anaerobic ammonia oxidizing cells, ultimately improving anaerobic ammonia oxidation performance and enhancing denitrification efficiency. This method is suitable when wastewater treatment facilities cannot provide sufficient mixing intensity or dead zones exist, using chemical stimulation to partially replace mechanical stirring, thus avoiding inefficient and unstable anaerobic ammonia oxidation processes.

[0089] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for improving anaerobic ammonia oxidation performance based on stimulating cell membrane stress, characterized in that, It includes: An anaerobic ammonia oxidation reaction was carried out by adding a coating agent to wastewater in a pulse mode. Anaerobic ammonia oxidizing bacteria are stimulated and enhanced to metabolize nitrogen by the membrane stress caused by the membrane agent. The coating agent is β-cyclodextrin; The pulse mode includes the addition of the coating reagent at least once every 24 hours; Using the pulsed dosing method, the lipid removal rate of β-cyclodextrin and the lipid synthesis rate of anaerobic ammonia-oxidizing cells are balanced over time.

2. The method according to claim 1, characterized in that, The coating agent is further dissolved before being added to the wastewater.

3. The method according to claim 1, characterized in that, The concentration of the coating reagent solution is 580 μM-610 μM.

4. The method according to claim 3, characterized in that, The concentration of the coating reagent solution is 600 μM.

5. The method according to claim 1, characterized in that, The denitrification efficiency of wastewater after adding the coating reagent is 67.4% ± 4.8%.

6. The method according to claim 1, characterized in that, Anaerobic ammonia oxidation is carried out in a sequencing batch reactor (SBR) mode with a cycle of 10-13 hours and an exchange rate of 50%.

7. The method according to claim 6, characterized in that, The cycle of the sequential batch operation is 12 hours.

8. The method according to claim 7, characterized in that, The sequential batch operation includes an influent stage, a reaction stage, a sedimentation stage, and a drainage stage; The water inlet stage lasts for 3-6 minutes, the reaction stage lasts for 11-12 hours, the sedimentation stage lasts for 18-22 minutes, and the drainage stage lasts for 4-6 minutes.

9. The method according to claim 8, characterized in that, In the sequential batch operation, the water inlet stage lasts for 5 minutes, the reaction stage lasts for 11.5 hours, the sedimentation stage lasts for 20 minutes, and the drainage stage lasts for 5 minutes.

10. The application of the method as described in any one of claims 1-9 in the treatment of wastewater by anaerobic ammonia oxidation.

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