Short-cut nitrification promoter and its application in short-cut nitrification-denitrification of ammonia-nitrogen wastewater

Abstract

The present invention belongs to the field of biological treatment of wastewater in environmental engineering, and specifically discloses a short-term nitrification promoter, comprising 1 to 30 mol% of formula 1, 45 to 95 mol% of formula 2, and 1 to 35 mol% of formula 3. The present invention also includes a method for performing short-term nitrification and denitrification on ammonia nitrogen-containing wastewater using the promoter. The short-term nitrification promoter described in the present invention can achieve a good nitrite nitrogen accumulation effect, with a nitrite nitrogen accumulation rate of more than 85%. The composition does not affect the denitrification efficiency in the biological denitrification process (the total nitrogen removal rate is more than 95%), and compared with traditional denitrification processes, it can reduce the aeration volume and greatly reduce the amount of carbon source required for subsequent denitrification.

Description

Technical Field

[0001] The invention belongs to the field of biological treatment of environmental engineering sewage, and particularly relates to a composition capable of promoting biological short-range nitrification and its application. Background Art

[0002] The common method for treating wastewater containing ammonia nitrogen is biological method. Traditional biological denitrification technology includes two steps: nitrification and denitrification. The nitrification process is carried out in two steps. First, the ammonia nitrogen in the wastewater is oxidized to nitrite nitrogen under the action of ammonia oxidizing bacteria (AOB), and then the nitrite nitrogen is oxidized to nitrate nitrogen under the action of nitrite oxidizing bacteria (NOB). Short-term nitrification controls the nitrification process to the step of producing nitrite, which can reduce the oxygen consumption in the nitrification stage and reduce the amount of carbon source added in the subsequent denitrification process, which can reduce energy consumption and save costs. Therefore, the enrichment and cultivation of ammonia oxidizing bacteria is very critical. From the perspective of the enzyme level involved in the microbial nitrification process, the enzymes involved in the nitrification reaction are mainly ammonia monooxygenase, hydroxylamine oxidoreductase and nitrite oxidase. Microorganisms carry out metabolic activities under the catalysis of these related enzymes, accompanied by complex material and energy conversion. The use of a composition that can promote short-term nitrification to increase the activity of ammonia monooxygenase and hydroxylamine oxidoreductase in nitrifying bacteria and inhibit the activity of nitrite oxidase can control the nitrification reaction to stay at the nitrite nitrogen step, which is one of the effective ways to start and operate biological short-term nitrification.

[0003] At present, many studies have focused on eliminating NOB and enriching AOB by controlling process parameters such as pH and dissolved oxygen, and controlling the traditional full-process nitrification to the nitrite nitrogen stage to achieve short-term nitrification. However, it is difficult to quickly start and maintain short-term nitrification by simply controlling process parameters, which affects its application in actual wastewater treatment. In addition, publication number JP2023139704A discloses a wastewater treatment method, which records the use of dithioformate as a nitrification inhibitor, but it does not involve research on improving the accumulation of nitrite nitrogen and the impact of subsequent denitrification.

[0004] In summary, there are relatively few short-term nitrification promoters in the prior art that can promote short-term nitrification and basically do not inhibit subsequent denitrification. Summary of the Invention

[0005] In view of the shortage of short-term nitrification promoters and the fact that the few promoters available are prone to inhibiting the subsequent denitrification effect, the first purpose of the present invention is to provide a short-term nitrification promoter to improve the short-term nitrification effect of ammonia-nitrogen wastewater.

[0006] The present invention also provides a method for performing short-term denitrification and denitrification on ammonia-nitrogen-containing wastewater using the short-term nitrification promoter, aiming to improve the short-term denitrification effect and avoid denitrification inhibition, thereby improving the treatment effect of ammonia-nitrogen-containing wastewater.

[0007] A short-range nitration promoter comprising 1 to 30 mol% of formula 1, 45 to 95 mol% of formula 2, and 1 to 35 mol% of formula 3;

[0008]

[0009] In Formulas 1 to 3, R1 to R6 are independently C1 to C6 alkyl, C2 to C6 alkene, C2 to C6 alkynyl, or C3 to C6 cycloalkyl;

[0010] The M1 and M2 are independently H, Na, K or NH4.

[0011] In the present invention, Formulas 1 to 3 are innovatively combined, and further coordinated with the joint control of the molar content of the three, so that unexpected synergy can be achieved, which can significantly improve the short-term nitrification effect of ammonia-containing wastewater, improve the cumulative effect of nitrite nitrogen, and prevent its further oxidation to nitrate nitrogen. Not only that, it can also avoid subsequent denitrification inhibition, thereby effectively improving the nitrification-denitrification effect of ammonia-nitrogen-containing wastewater, reducing oxygen demand and carbon supply. The present invention uses the short-term nitrification promoter to achieve rapid startup and stable operation of short-term nitrification under high dissolved oxygen conditions, with a short startup time, good effect, and simple operation. While obtaining high nitrite accumulation, the ammonia nitrogen removal rate also remains at a high level, and it will not affect subsequent biological denitrification.

[0012] In the present invention, in Formulae 1 to 3, R1 to R6 are independently C1 to C4 alkyl groups, preferably methyl or ethyl groups.

[0013] In the present invention, the combined control of the molar content of the components of Formulas 1 to 3 is the key to synergistically improving the short-term nitrification promotion effect and reducing the subsequent denitrification inhibition. Preferably, the short-term nitrification promoter contains 5-25 mol% of Formula 1, 65-90 mol% of Formula 2, and 4-10 mol% of Formula 3.

[0014] Preferably, the short-range nitration promoter contains 16-18 mol% of Formula 1, 76-79 mol% of Formula 2 and 4-6 mol% of Formula 3.

[0015] Furthermore, the short-range nitration promoter contains 16-18 mol% of Formula 1, 4-6 mol% of Formula 3, and the balance is Formula 2.

[0016] The present invention also provides a method for the short-cut nitrification of ammonia nitrogen-containing wastewater, wherein the short-cut nitrification promoter is mixed with the ammonia nitrogen-containing wastewater to be treated and subjected to microbial short-cut nitrification to obtain nitrite nitrogen-treated water.

[0017] In the present invention, the short-term denitrification promoter can be added to the conventional short-term denitrification process technology, which can effectively enrich the ammonia oxidizing bacteria in the microbial nitrification process of ammonia-nitrogen-containing wastewater and inhibit nitrite oxidizing bacteria, thereby improving the accumulation of nitrite-nitrogen in the short-term nitrification. In addition, it basically does not inhibit subsequent denitrification.

[0018] In the present invention, the addition amount of the short-range nitrification promoter can be adjusted as needed, for example, it can be 5 to 15 mg / L, preferably 8 to 12 mg / L.

[0019] The method of the present invention can be adapted to any wastewater containing ammonia nitrogen, for example, wastewater having an ammonia nitrogen concentration between 50-400 mg / L.

[0020] In the present invention, the short-cut nitrification process, except for the addition of the short-cut nitrification promoter, can be operated and parameterized in accordance with conventional methods. For example, during the microbial short-cut nitrification process, the pH value is controlled at 6 to 7.5, the temperature is between 10°C and 30°C, the dissolved oxygen is between 5 and 7 mg / L, and the nitrification time is 6 to 24 hours.

[0021] For example, in the treatment process of the present invention, sludge (containing AOB and NOB) is pre-inoculated into the shortcut nitrification reactor, and then the composition and the ammonia nitrogen-containing wastewater to be treated are introduced for microbial shortcut nitrification treatment;

[0022] Preferably, the sludge is sludge from an aerobic tank in a sewage treatment plant, and the sludge concentration is 2500-4000 mg / L.

[0023] The present invention also provides a short-cut nitrification-denitrification method for ammonia nitrogen-containing wastewater, wherein the ammonia nitrogen-containing wastewater is subjected to microbial nitrification using the ammonia nitrogen-containing wastewater short-cut nitrification method to obtain nitrite nitrogen-treated water, which is then subjected to microbial denitrification treatment to obtain ammonia nitrogen-free treated water.

[0024] The short-range nitrification promoter of the present invention can not only effectively promote short-range nitrification and avoid further oxidation, but also avoid inhibiting the enzymatic reaction activity of subsequent denitrification. When combined with conventional denitrification treatment, it can achieve effective nitrification degradation of ammonia nitrogen wastewater.

[0025] In the present invention, the denitrification process can be conventional, for example, the C / N ratio during the denitrification process is 2.5-4, the dissolved oxygen during the reaction is lower than 0.2 mg / L, the temperature is between 10-30° C., and the treatment time is 6-18 hours.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] The present invention innovatively combines Formulas 1 to 3, further combining the combined control of the molar content of the three, so as to achieve synergy, improve the enrichment and activity of AOB, and inhibit the activity of NOB, thereby promoting short-term nitrification and avoiding further oxidation of nitrite nitrogen; this can save oxygen consumption during the nitrification process and reduce the amount of carbon source added during the subsequent denitrification process, thereby reducing energy consumption and saving costs. In addition, thanks to the synergistic combination of the promoters, the present invention does not need to control the reaction process under harsh environmental conditions. The short-term nitrification achieved is not dependent on the composition. After the short-term nitrification is successfully started, even if the addition of the composition is stopped, the accumulation effect of nitrite in the short-term nitrification will not be affected, and the composition has no inhibitory effect on the subsequent denitrification effect.

[0028] There is no need to deliberately control the dissolved oxygen during the entire startup process. The dissolved oxygen concentration is always maintained at a high level. High dissolved oxygen can achieve a higher nitrification rate, and sludge swelling is less likely to occur, and the sludge is not easy to disintegrate. DETAILED DESCRIPTION

[0029] To make the purpose, method and advantages of the present invention clearer, the technical solutions adopted in this application are described in detail below with reference to examples. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0030] The detection methods and standards used in the present invention are:

[0031] The determination of ammonia nitrogen was based on the Nessler reagent spectrophotometric method (HJ 535-2009); the determination of nitrate nitrogen was based on the ultraviolet spectrophotometric method (HJ / T346-2007); the determination of nitrite nitrogen was based on the spectrophotometric method (GB 7493-87); and the determination of COD was based on the rapid digestion spectrophotometric method (HJ / T399-2007).

[0032] The present invention utilizes a short-range nitrification promoter, which selectively suppresses nitrite-oxidizing bacteria and enriches ammonia-oxidizing bacteria in the influent, until the ammonia-oxidizing bacteria become the dominant species in the reactor, achieving biological short-range nitrification. The short-range nitrification water is discharged into a denitrification reactor for denitrification. The effluents from the short-range nitrification and denitrification processes are collected separately, and the ammonia nitrogen, nitrate nitrogen, and nitrite nitrogen content in the effluents are measured to calculate the ammonia nitrogen removal rate and nitrite nitrogen accumulation rate.

[0033] The short-cut nitrification-denitrification treatment process of the present invention may include the following steps:

[0034] (1) Inoculated sludge: The sludge used for microbial short-cut nitrification and denitrification in the present invention comes from the aerobic tank sludge of a sewage treatment plant, and the sludge concentration is 2500-4000 mg / L;

[0035] (2) The ammonia nitrogen concentration of the influent of the short-cut nitrification reactor is between 50-400 mg / L, the pH value is between 6.0-7.5, the pH value is controlled by the pH automatic control system during the process, the temperature is between 10 and 30 ° C, the dissolved oxygen is between 5 and 7 mg / L, and the aeration time is 6 to 24 hours;

[0036] (3) After nitrification, the water produced by the nitrification reactor is discharged into the denitrification reactor for microbial denitrification. The influent nitrite nitrogen concentration is 30-350 mg / L, glucose is added to the influent as a carbon source, the C / N ratio is 3, the dissolved oxygen during the reaction is less than 0.2 mg / L, the temperature is between 10 and 30 ° C, the anaerobic stirring time is 6-18 h, and the stirring blade speed is 100 rpm;

[0037] (4) Both the microbial nitrification and denitrification reactors were sequencing batch reactors. The nitrification reactor had an effective volume of 1 L and was equipped with an aeration head at the bottom. It was internally equipped with online pH and dissolved oxygen monitoring probes, which transmitted data in real time to a PLC control cabinet. The PLC control cabinet controlled the peristaltic pump to stop and start according to the set pH value and to add alkali solution. The added alkali solution was a NaCO3 solution with a concentration of 10 wt%. The denitrification reactor had an effective volume of 1 L and was internally equipped with a stirring paddle and online pH, ORP, and dissolved oxygen monitoring probes.

[0038] In the present invention, by combining the structural compounds of Formula 1, Formula 2 and Formula 3, and further coordinating the combined control of the molar ratio of the components, synergy can be achieved to improve the short-range nitrification and denitrification effects. In the present invention, there are no special requirements for the groups of Formulas 1 to 3. In the following cases, Formula 1 is represented by Formula 1-A (Formula 1 in which R1 / R2 are both methyl and M1 is Na), Formula 2 is represented by Formula 2-A (Formula 2 in which R3 / R4 are both methyl and M2 is H), and Formula 3 is represented by Formula 3-A (Formula 3 in which R5 / R6 are both methyl). The above is only a typical implementation and does not constitute a necessary feature limitation for the implementation of the present invention.

[0039] Examples 1 to 4

[0040] The effects of compositions with different proportions on the accumulation of nitrite nitrogen in short-range nitrification were investigated. The reactor used in this experiment was a sequencing batch reactor with an effective volume of 1L, an influent ammonia nitrogen concentration of 400mg / L, a pH value of 6.0-7.5, a dissolved oxygen concentration of 5-7mg / L, and a temperature of 10-30°C during the experiment. Compositions with different proportions (as shown in Table 1) were added to the reactor, and the concentrations were all 1g / L. Each cycle was added according to the concentration of 10mg / L of the composition (referring to the promoter comprising Formula 1-Formula 2 and Formula 3), and the mixture was run continuously for 10 cycles. The concentrations of ammonia nitrogen, nitrate nitrogen and nitrite nitrogen in the effluent were sampled and analyzed. The specific preparation conditions and the results of the short-range nitrification effluent are shown in Table 1.

[0041] Table 1 Investigating the effects of different ratios of compositions on short-range nitrification

[0042]

[0043] As can be seen from the nitrification effluent quality analysis results of the various examples in Table 1, different composition ratios resulted in different effects on promoting short-range nitrification. The best effect was achieved when the molar ratio of 1-A:2-A:3-A was 14:67:4, with an accumulation rate of nitrite nitrogen reaching 89% and an ammonia nitrogen removal rate exceeding 97%.

[0044] Examples 5 to 7

[0045] The composition prepared according to the ratio of Example 2 was added to the reactor at a concentration of 1 g / L. The composition was added at a concentration of 10 mg / L in each cycle to investigate the effect of the composition on the accumulation of nitrite nitrogen in the shortcut nitrification process under different influent ammonia nitrogen concentrations. The composition was run continuously for 10 cycles at each ammonia nitrogen concentration, and the concentrations of ammonia nitrogen, nitrate nitrogen and nitrite nitrogen in the effluent were sampled and analyzed. The specific results are shown in Table 2.

[0046] Table 2 Short-range nitrification effect of the investigation composition on wastewater with different ammonia nitrogen concentrations

[0047]

[0048] From the nitrification effluent water quality analysis results of each embodiment in Table 2, it can be seen that when the influent ammonia nitrogen is 100, 200, and 300 mg / L, the addition of the composition can also achieve a good nitrite nitrogen accumulation effect, and the nitrite nitrogen accumulation rate reaches 88.0%, 87.8%, and 89.2%, respectively, and the ammonia nitrogen removal rate is always maintained at above 95%.

[0049] Examples 8 to 11

[0050] The nitrification water (i.e., the short-cut nitrification water of Examples 2 and 5 to 7) with an influent ammonia nitrogen concentration of 50 mg / L (Example 5), 100 mg / L (Example 6), 200 mg / L (Example 7), and 400 mg / L (Example 2) was respectively discharged into a denitrification reactor. The reactor was a sequencing batch reactor with an effective volume of 1 L. Glucose was added to the influent as a carbon source with a C / N ratio of 3. During the reaction, the dissolved oxygen was less than 0.2 mg / L. The treated water samples were taken and the concentrations of nitrate nitrogen, nitrite nitrogen, and COD were analyzed and tested. The removal rates of nitrate nitrogen, nitrite nitrogen, and COD were calculated. The specific results are shown in Table 3.

[0051] Table 3 investigates the denitrification effect of nitrification water under different influent ammonia nitrogen concentrations

[0052]

[0053] It can be seen from the denitrification effluent quality of each embodiment in Table 3 that when the nitrified effluent produced by the addition of the composition to achieve short-cut nitrification is discharged into the denitrification reactor for denitrification treatment, the removal rates of nitrite nitrogen and nitrate nitrogen are both above 99%, and the removal rate of COD is above 88%.

[0054] Examples 12 to 15

[0055] The operating conditions of the nitrification reactor remained the same as those of Examples 1 to 4. For Examples 5, 6, 7, and 2, in which short-range nitrification was achieved by adding the composition, the addition of the composition was stopped starting from the 11th cycle. The reactor was then operated continuously for 10 cycles. Samples were collected after nitrification and analyzed for ammonia nitrogen, nitrate nitrogen, and nitrite nitrogen. The ammonia nitrogen removal rate and nitrite nitrogen accumulation rate were calculated. The specific results are shown in Table 4.

[0056] Table 4 investigates the short-range nitrification effect under different influent ammonia nitrogen concentration conditions after stopping the addition of the composition

[0057]

[0058] It can be seen from the effluent quality of each embodiment in Table 4 that after the short-range nitrification is successfully started, the addition of the composition is stopped and the ammonia nitrogen removal rate is still maintained at more than 95%, and the accumulation rate of nitrite nitrogen does not deteriorate due to the cessation of the addition of the composition and is still maintained at more than 85%.

[0059] Comparative Examples 1 to 3

[0060] The inlet ammonia nitrogen concentration and operating conditions of the nitrification reactor were consistent with those in Example 2. 1-A, 2-A, and 3-A were added to the inlet water separately, and the amount added was consistent with the total amount added in Example 2. Each concentration was continuously operated for 10 cycles, and water samples were taken out for analysis to test the concentrations of ammonia nitrogen, nitrate nitrogen, and nitrite nitrogen, and the ammonia nitrogen removal rate and nitrite nitrogen accumulation rate were calculated. The specific results are shown in Table 5.

[0061] Table 5 investigates the effects of adding 1-A, 2-A, and 3-A alone on short-range nitrification

[0062]

[0063] As shown in Table 5, when 10 mg / L of either 1-A or 3-A was added alone, the ammonia nitrogen removal rate was significantly affected, and both ammonia-oxidizing bacteria and nitrite-oxidizing bacteria were inhibited to varying degrees. Ammonia nitrogen removal rates were only 2.9% and 0.6%, respectively, while nitrite nitrogen accumulation rates were 23.3% and 35.3%, respectively. When 10 mg / L of 2-A was added alone, the ammonia nitrogen removal rate was not affected, remaining at 99%, while the nitrite nitrogen accumulation rate was 35.7%.

[0064] Comparative Examples 6 to 9

[0065] The nitrification reactor was operated under the same conditions as in Examples 1-4, except that the composition was not added to the influent. The accumulation of nitrite nitrogen during the short-range nitrification process was investigated at different influent ammonia nitrogen concentrations. Each concentration was operated for 10 consecutive cycles. Water samples were taken for analysis of ammonia nitrogen, nitrate nitrogen, and nitrite nitrogen concentrations, and the ammonia nitrogen removal rate and nitrite nitrogen accumulation rate were calculated. The specific results are shown in Table 6.

[0066] Table 6 Investigation of the short-range nitrification effect under different influent ammonia nitrogen concentration conditions when no composition is added

[0067]

[0068] From the water quality analysis results of the nitrification effluent of Comparative Examples 6 to 8 in Table 6 and Comparative Example 1 in Table 5, it can be seen that when the inlet ammonia nitrogen concentration is 50, 100, 200, and 400 mg / L, respectively, without adding the composition, the ammonia nitrogen removal rate is basically maintained at above 95%, and the accumulation rate of nitrite nitrogen in the effluent is maintained at 7.9%, 9.0%, 15.9%, and 16.8%, respectively.

[0069] Comparative Examples 10 to 13

[0070] Simulated wastewater was prepared according to the influent nitrite and nitrate concentrations of Examples 8 to 11, differing from Examples 13 to 16 only in the absence of the composition. The prepared simulated wastewater (excluding the promoter component of Examples 8 to 11, and other parameters, such as nitrite nitrogen, were the same as those of the initial denitrification wastewater of Examples 8 to 11) was subjected to denitrification treatment. The operating conditions during the denitrification process remained the same as in Examples 8 to 11. Samples were collected after treatment and analyzed for nitrite nitrogen, nitrate nitrogen, and COD, and the removal rates of nitrite nitrogen, nitrate nitrogen, and COD were calculated. The specific results are shown in Table 7.

[0071] Table 7 investigates the effect of the composition on denitrification

[0072]

[0073] From the effluent water quality analysis results of Comparative Examples 10 to 13 in Table 7, it can be seen that when the composition is not present in the influent, the removal rates of nitrite nitrogen and nitric nitrogen during the denitrification process are above 99%, and the removal rate of COD is above 88%. Compared with Examples 8 to 11 containing the composition, the removal rates of nitrate nitrogen, nitrite nitrogen, and COD do not change significantly, indicating that the composition does not affect the denitrification effect.

[0074] As can be seen from Examples 1-15 and Comparative Examples 1-13, the composition for promoting short-range nitrification and denitrification prepared by the present invention can achieve a nitrite nitrogen accumulation rate of over 85% while maintaining a high ammonia nitrogen removal rate. Even after the short-range nitrification is successfully started, even if the addition of the composition is stopped, the nitrite nitrogen accumulation rate can still be maintained at 85%.

Claims

1. A short-range nitrification promoter, characterized in that: Containing 1-30 mol% of Formula 1, 45-95 mol% of Formula 2, and 1-35 mol% of Formula 3; Formula 1 Formula 2 Formula 3 In Formulas 1 to 3, R1 to R6 are independently C1 to C6 alkyl, C2 to C6 alkene, C2 to C6 alkynyl, or C3 to C6 cycloalkyl; The M1 and M2 are independently H, Na, K or NH4.

2. The short-range nitration promoter according to claim 1, characterized in that In Formulae 1 to 3, R1 to R6 are independently C1 to C4 alkyl groups.

3. The short-range nitration promoter according to claim 2, characterized in that In Formulae 1 to 3, R1 to R6 are independently methyl or ethyl.

4. The short-range nitration promoter according to claim 1, characterized in that The short-range nitration promoter contains 5-25 mol% of formula 1, 65-90 mol% of formula 2 and 4-10 mol% of formula 3.

5. The short-range nitration promoter according to claim 4, characterized in that The short-range nitration promoter contains 16-18 mol% of formula 1, 76-79 mol% of formula 2 and 4-6 mol% of formula 3.

6. A method for the short-cut nitrification of ammonia-nitrogen-containing wastewater, characterized in that: The short-cut nitrification promoter according to any one of claims 1 to 5 is mixed with the ammonia nitrogen-containing wastewater to be treated and subjected to microbial short-cut nitrification to obtain nitrite nitrogen-treated water.

7. The method for shortcut nitrification of ammonia-nitrogen-containing wastewater according to claim 6, wherein: The addition amount of the short-range nitrification promoter is 5-15 mg / L.

8. The method for short-cut nitrification of ammonia-nitrogen-containing wastewater according to claim 7, wherein: The addition amount of the short-range nitrification promoter is 8-12 mg / L.

9. The method for shortcut nitrification of ammonia-nitrogen-containing wastewater according to claim 6, wherein: The ammonia nitrogen concentration of ammonia nitrogen-containing wastewater is between 50-400 mg / L.

10. The method for short-cut nitrification of ammonia-nitrogen-containing wastewater according to claim 6, wherein: During the microbial short-range nitrification process, the pH value is controlled at 6~7.5, the temperature is between 10~30℃, the dissolved oxygen is 5~7mg / L, and the nitrification time is 6~24h.

11. The method for shortcut nitrification of ammonia-nitrogen-containing wastewater according to any one of claims 6 to 10, characterized in that: The short-cut nitrification reactor is inoculated with sludge in advance, and then the short-cut nitrification promoter and the ammonia nitrogen-containing wastewater to be treated are introduced to carry out microbial short-cut nitrification treatment.

12. The method for shortcut nitrification of ammonia nitrogen-containing wastewater according to claim 11, wherein: The sludge is the sludge from the aerobic tank of the sewage treatment plant, and the sludge concentration is 2500-4000 mg / L.

13. A short-cut nitrification-denitrification method for ammonia-nitrogen wastewater, characterized in that: The ammonia nitrogen-containing wastewater is subjected to microbial nitrification using the ammonia nitrogen-containing wastewater shortcut nitrification method according to any one of claims 6 to 12 to obtain nitrite nitrogen-treated water, which is then subjected to microbial denitrification treatment to obtain denitrified treated water.

14. The method for the short-cut nitrification-denitrification of ammonia nitrogen-containing wastewater according to claim 13, characterized in that: The C / N ratio during the denitrification process is 2.5~4, the dissolved oxygen during the reaction is lower than 0.2mg / L, the temperature is between 10~30℃, and the treatment time is 6~18h.

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