Method for starting up short-cut nitrification-anammox process by domesticating aerobic activated sludge

Abstract

This invention discloses a method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonia oxidation process, comprising: S1. filling the reactor with activated carbon packing material and inoculating it with aerobic activated sludge; S2. introducing water into the reactor, wherein the concentration of ammonia nitrogen in the influent is 135-145 mg·L⁻¹. ‑1 The concentration of nitrite nitrogen is 0 mg·L⁻¹. ‑1 The influent was not deoxygenated; S3. Operate the reactor and control the reactive oxygen species concentration in stages: Stage I: Days 0-25, control the reactive oxygen species concentration to be 0.2 < DO ≤ 0.3 mg·L ‑1 Phase II: Days 26–60, maintain reactive oxygen species concentration at 0.3 < DO ≤ 0.5 mg·L⁻¹ ‑1 Phase III: Days 61–150, maintain reactive oxygen species concentration at 0.5 < DO ≤ 0.7 mg·L⁻¹ ‑1 Phase IV: Days 151–230, maintain reactive oxygen species concentration at 0.4 < DO ≤ 0.5 mg·L⁻¹ ‑1 The method of this invention achieves efficient enrichment of AOB and AnAOB and NOB suppression through the synergistic effect of dissolved oxygen gradient regulation and activated carbon packing, significantly shortening the start-up period; this method is suitable for denitrification treatment of wastewater with high ammonia nitrogen and low carbon-to-nitrogen ratio (C / N).

Description

Technical Field

[0001] This invention relates to the field of wastewater biological treatment technology, specifically to a method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process. Background Technology

[0002] Traditional biological nitrogen removal processes suffer from problems such as high aeration energy consumption, the need for external carbon sources, large sludge production, and greenhouse gas emissions. Short-cut nitrification-anaerobic ammonium oxidation (PN / A) processes offer advantages such as no need for organic carbon sources, low sludge production, and low energy consumption; however, their practical application still faces bottlenecks such as difficulties in the synergistic enrichment of functional ammonia-oxidizing bacteria (AOB) and anaerobic ammonium-oxidizing bacteria (AnAOB), difficulties in inhibiting nitrite-oxidizing bacteria (NOB), and long start-up cycles. In existing technologies, start-up methods using anaerobic ammonium oxidation sludge as seed sludge are easily affected by influent fluctuations, and AnAOB abundance is prone to decline.

[0003] Therefore, there is an urgent need to provide an efficient and stable PN / A process start-up method. Summary of the Invention

[0004] The technical problem to be solved by this invention is to provide a short-cut nitrification-anaerobic ammonia oxidation process start-up method based on aerobic activated sludge acclimation. Through the synergistic effect of dissolved oxygen (DO) gradient regulation and activated carbon packing, the method achieves efficient enrichment of AOB and AnAOB and NOB inhibition, significantly shortening the start-up cycle. This method is suitable for denitrification treatment of wastewater with high ammonia nitrogen and low carbon-to-nitrogen ratio (C / N).

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] This invention provides a method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process, comprising the following steps:

[0007] S1. Fill the reactor with activated carbon packing material and inoculate it with aerobic activated sludge;

[0008] S2. Water is introduced into the reactor, and the concentration of ammonia nitrogen in the water is 135–145 mg·L⁻¹. -1 The concentration of nitrite nitrogen is 0 mg·L⁻¹. -1 Furthermore, the influent water was not deoxygenated;

[0009] S3. Operate the reactor and perform gradient control of the reactive oxygen species concentration within the reactor in stages:

[0010] Phase I: Days 0-25, maintain reactive oxygen species concentration at 0.2 < DO ≤ 0.3 mg·L⁻¹ -1 ;

[0011] Phase II: Days 26–60, maintain reactive oxygen species concentration at 0.3 < DO ≤ 0.5 mg·L⁻¹ -1 ;

[0012] Phase III: Days 61–150, maintain reactive oxygen species concentration at 0.5 < DO ≤ 0.7 mg·L⁻¹ -1 ;

[0013] Phase IV: Days 151–230, maintain reactive oxygen species concentration at 0.4 < DO ≤ 0.5 mg·L⁻¹ -1 .

[0014] Further, in step S1 of the present invention, the reactor is preferably an upflow anaerobic sludge bed (UASB) reactor. Preferably, the effluent outlet of the UASB reactor is connected to a secondary sedimentation tank to intercept a portion of the suspended sludge and to perform sludge recirculation, so as to maintain the total amount of biomass in the reactor.

[0015] Further, in step S1 of the present invention, the biomass concentration of the aerobic activated sludge inoculated in the reactor, based on the volatile solids concentration (VSS), is preferably 1.496 ± 0.005 g·L⁻¹. -1 Preferably, the dominant bacterial genus in the granular sludge after aerobic activated sludge acclimation is Candidatus Kuenenia.

[0016] Furthermore, in step S1 of this invention, activated carbon packing is filled into the reactor to retain sludge and maintain the stable operation of the system. In some preferred embodiments, the activated carbon is coconut shell activated carbon, with a preferred particle size of 8-16 mesh and a preferred specific surface area of ​​1000-1300 m². 2 ·g -1 Furthermore, the amount of activated carbon packing is 30% to 40% of the effective volume of the reactor, and for example, it can be 30%, 32%, 34%, 35%, 36%, 38%, 40%, etc.

[0017] Furthermore, in step S2 of the present invention, the influent is preferably a peristaltic pump, and the total nitrogen load of the influent is preferably maintained at 0.50–0.60 kg-N·m. -3 ·d -1 For example, the values ​​can be 0.50, 0.52, 0.55, 0.58, or 0.60 kg-N·m. -3 ·d -1 wait.

[0018] Further, in step S2 of the present invention, the pH of the influent is preferably controlled between 7.0 and 7.5, and can be, for example, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, etc. The hydraulic retention time is preferably between 2.5 and 3.5 hours, and can be, for example, 2.5, 2.8, 3.0, 3.2, 3.5 hours, etc. Further, the reactor is preferably operated under conditions of darkness and room temperature.

[0019] Further, in step S2 of the present invention, the influent is simulated wastewater that has not undergone aeration and deoxygenation treatment. In some preferred embodiments, the simulated wastewater contains NH4Cl, CaCl2·2H2O, MgCl2·6H2O, NaHCO3, trace element I reserve solution, and trace element II reserve solution; wherein, the trace element I reserve solution is prepared by EDTA and FeSO4; the trace element II reserve solution contains: EDTA, ZnSO4·7H2O, CoCl2·6H2O, MnCl2·4H2O, CuSO4·5H2O, NaMoO4·2H2O, NiCl2·6H2O, and H3BO4.

[0020] Furthermore, in step S3 of the present invention, an aeration head is connected to the reactor and submerged at the bottom of the reactor to adjust the dissolved oxygen concentration inside the reactor through aeration treatment.

[0021] Furthermore, in step S3 of the present invention, in stage II, the short-cut nitrification is determined to be successfully started by a nitrite accumulation rate (NiAR) ≥ 90%; in stage IV, the PN / A process is determined to be successfully started and operating stably by a total nitrogen removal rate (NRE) ≥ 70%.

[0022] Furthermore, in step S3 of this invention, based on the volatile solids concentration (VSS), after successful acclimatization of the inoculated aerobic activated sludge, the biomass concentration of the sludge in the reactor is 1.83 ± 0.005 g·L⁻¹. -1 .

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1. In this invention, the dissolved oxygen (DO) gradient control strategy in the reactor regulates the microbial competition relationship in stages, and the activated carbon packing maintains the system stability through physical interception and biofilm formation. The two work together to significantly improve the engineering feasibility of the PN / A process, achieve efficient enrichment of AOB and AnAOB and NOB inhibition, and significantly shorten the start-up period.

[0025] 2. The method of the present invention has the advantages of fast start-up, high denitrification efficiency and low operating cost. It is suitable for denitrification treatment of wastewater with high ammonia nitrogen and low carbon-to-nitrogen ratio (C / N), and provides technical support for the engineering application of this process.

[0026] 3. Experiments have demonstrated that the method of this invention successfully achieved short-cut nitrification in the reactor after 34 days of continuous aeration. When the system was stable, the ammonia nitrogen removal rate reached 52.6%, and the nitrite accumulation rate reached 92.2%. Enrichment of anaerobic ammonia-oxidizing bacteria was detected on day 95. The PN / A system was successfully started up and operated stably on day 191. After system stabilization, the ammonia nitrogen removal rate was 90±2%, the total nitrogen removal rate was 75±5%, and the nitrogen volumetric removal rate was 0.80±0.02 kg-N·m³. -3 ·d -1 . Attached Figure Description

[0027] Figure 1 This shows the nitrogen variation trend of the reactor inlet and outlet water in Example 1;

[0028] Figure 2 The changes in ammonia nitrogen removal rate (ARE) and nitrite accumulation rate (NiAR) during the DO stage adjustment of the reactor in Example 1 are shown.

[0029] Figure 3 The changes in sludge activity in the reactor of Example 1;

[0030] Wherein, SAA is the specific anaerobic ammonia oxidation activity, SAOR is the specific ammonia oxidation rate, and SNOR is the specific nitrate oxidation rate. Detailed Implementation

[0031] The present invention will be further described below with reference to specific embodiments, so that those skilled in the art can better understand and implement the present invention, but the embodiments are not intended to limit the present invention.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0033] Unless otherwise specified, the experimental methods used in the following examples and comparative examples are conventional methods, and the materials and reagents used are commercially available.

[0034] Example 1

[0035] This embodiment provides a method for rapidly starting a short-cut nitrification-anaerobic ammonium oxidation process based on aerobic activated sludge acclimation through dissolved oxygen (DO) gradient regulation and the synergistic effect of activated carbon packing. The specific steps are as follows:

[0036] (1) Example 1 used a UASB reactor with an effective volume of 1.0 L, filled with 300 mL of coconut shell activated carbon as a microbial carrier. Aerobic activated sludge was inoculated into the UASB reactor, with a mixed liquor sludge concentration (MLSS) of 2.354 g·L⁻¹. -1 The volatile suspended solids concentration (MLVSS) of the sludge mixed liquor was 1.496 g·L⁻¹. -1 The reactor was operated at room temperature with an ammonia nitrogen concentration of 140 mg·L⁻¹. -1 Simulated wastewater without deoxygenation treatment was used as the influent, with a hydraulic retention time of 3 ± 0.5 h and a pH controlled between 7.0 and 7.5 for sludge acclimation. Aeration heads were connected to the reactor and submerged at the bottom, and DO was controlled to 0.2–0.3 mg·L⁻¹ through aeration. -1 .

[0037] NH4 required for short-range nitration + -N is provided by NH4Cl, with KHCO3 as the inorganic carbon source. The composition of other components in the simulated wastewater used is as follows:

[0038]

[0039] The composition of the trace element I stock solution is as follows:

[0040]

[0041] The composition of the trace element II stock solution is as follows:

[0042]

[0043] (2) Intermittently monitor NH4 in the reactor effluent weekly. + NO2 - and NO3 - After Phase I cultivation, NiAR reached 85%–95% after 25 days, and ammonia nitrogen removal rate reached 30%; ARE was basically maintained at 20%–30%; the low aeration strategy has achieved NO2 removal. - Through accumulation, a certain amount of AOB has been successfully enriched.

[0044] On day 25, the dissolved oxygen (DO) was increased to 0.3–0.5 mg·L⁻¹ using an aeration device. -1 After 60 days of cultivation, NiAR > 90% and ammonia nitrogen removal rate ARE was 50%, indicating that the short-cut nitrification start-up as expected in the experiment was successful. More than 50% of ammonia nitrogen was removed or converted into nitrite nitrogen, and NOB was successfully inhibited, complete nitrification was inhibited, and the nitrate nitrogen yield remained low, so that NiAR remained at a high level (90-95%) throughout the process.

[0045] On day 60, continue to increase DO to 0.5–0.7 mg / L. -1 In the early stages, the ammonia nitrogen removal rate in the system remained stable at 50-60%, but after 100 days, the ammonia nitrogen removal rate increased significantly to 70%, while the total nitrogen removal rate gradually increased and stabilized at 40%. Nitrite nitrogen remained stable at 45-55 mg·L⁻¹. -1 However, after 100 days, nitrate nitrogen was gradually produced and stabilized at 10 mg·L⁻¹. -1 NiAR also gradually decreased, suggesting that some AnAOB has been enriched in the PN / A system.

[0046] On day 150, the dissolved oxygen concentration in the reactor was reduced to 0.4–0.5 mg·L⁻¹. -1 Due to the sudden drop in dissolved oxygen concentration, the effluent ammonia nitrogen concentration fluctuated. However, after 200 days, the ammonia nitrogen removal rate rose to 85% and remained at 85-93%, while the total nitrogen removal rate also gradually increased, remaining at 70-80% after 200 days. The production of nitrite nitrogen also decreased during the sudden drop in dissolved oxygen concentration, demonstrating that dissolved oxygen regulation is a crucial factor affecting nitrite nitrogen production. In Stage IV, nitrite nitrogen produced from influent ammonia nitrogen via short-cut nitrification, acting as an electron acceptor in the anaerobic ammonia oxidation reaction, reacted with ammonia nitrogen in the influent, showing a gradual decreasing trend, and dropping to 10 mg·L⁻¹ after 200 days. -1 The concentration of nitrate nitrogen produced by anaerobic ammonia oxidation remains stable at 10–20 mg·L⁻¹. -1 Meanwhile, the total nitrogen removal load in the reactor decreased from 0.33 kg-N·m³ at 151 days. -3 ·d -1 It gradually increased to 0.86 kg-N·m at 231 days. -3 ·d -1 This indicates that after entering the fourth stage, the activity of anaerobic ammonia-oxidizing bacteria in the reactor continuously increases over time.

[0047] (3) At four different experimental points of 25, 60, 150 and 230 days, the AOB activity (ammonia nitrogen oxidation rate), NOB activity (nitrite oxidation rate) and AnAOB activity (anaerobic ammonia oxidation rate) in the system were measured to analyze the changes in microbial activity at different stages.

[0048] AOB activity increased from 1.04 mg-N·g in the first phase. -1 -VSS·h -1 Increased to 2.37 mg-N·g in the third stage -1 -VSS·h -1 During the gradual enrichment process, AnAOB also gradually increases its activity and remains stable in subsequent stages, eventually stabilizing at 1.93 mg-N·g. -1 -VSS·h-1 NOB is inhibited by anaerobic processes, with its activity decreasing from a maximum of 2.31 mg-N·g. -1 -VSS·h -1 It decreased to 0.54 mg-N·g in the final stage. -1 -VSS·h -1 The activity gradually decreased, and it did not interfere with the enrichment of AOB and AnAOB in the PNA system.

[0049] By comparing the activities of AOB, NOB, and AnAOB, the NOB activity was higher in the initially inoculated aerobic activated sludge, exhibiting strong activity within the system, while AOB also showed good activity. However, after the first stage of anaerobic inhibition, the NOB activity significantly decreased, while the AOB activity continued to increase. This indicates that the first three stages, as the initiation stage of short-cut nitrification, were successful.

[0050] (4) Sludge samples from four time points were used for community dynamic analysis. High-throughput sequencing results showed that at the PN / A stable backdoor level, the abundance of Proteobacteria, Planctomycetes, Bacteroidetes, and Actinobacteria was relatively high, reaching 21.1%, 43.2%, 9.0%, and 9.7%, respectively. Planctomycetes showed an increasing abundance trend in sludge samples, gradually increasing from 0 to 43.2%. At the genus level, the abundance of denitrifying bacteria and NOB decreased significantly, with NOB abundance decreasing from 5.4% to 0%; while the abundance of AOB and AnAOB gradually increased. AOB abundance increased significantly in stage II, from 3.9% to 9.4%, Candidatus Kuenenia increased from 0 to 42.3%, and Candidatus Brocadia increased from 0 to 0.8%. The results showed that the microbial community structure characteristics changed significantly during the controlled dissolved oxygen initiation of short-cut nitrification-anaerobic ammonium oxidation, and the microbial community had a good enrichment capacity for anaerobic ammonium oxidizing bacteria.

[0051] As shown in the results of Example 1, the dissolved oxygen gradient control strategy effectively inhibits NOB activity by rapidly enriching AOB and AnAOB. ​​The reactor in Example 1 completed the start-up and stable operation of the short-cut nitrification-anaerobic ammonium oxidation process system within 200 days, exhibiting good nitrogen removal performance and relative abundance of microorganisms. By day 34 of operation, the dissolved oxygen concentration in the reactor was 0.4–0.5 mg·L⁻¹. -1 Short-cut nitrification was successfully initiated; a small amount of anaerobic ammonia-oxidizing bacteria was observed to accumulate on day 95, with dissolved oxygen concentrations ranging from 0.5 to 0.7 mg / L. -1 On day 191, the short-cut nitrification-anaerobic ammonium oxidation system was successfully started up and operated stably, with a dissolved oxygen concentration of 0.4–0.5 mg·L⁻¹. -1The NRR reached 0.80 ± 0.02 kg-N·m -3 ·d -1 The total nitrogen removal rate (NRE) remained stable at around 75%, and the effluent ammonia nitrogen and nitrite nitrogen levels were maintained at 13±3 mg·L⁻¹. -1 and 5±3 mg·L -1 The nitrate nitrogen in the effluent also remained stable at 15±2 mg·L⁻¹. -1 ΔNO3 - -N / ΔNH4 + -N and ΔTN / ΔNH4 + -N stabilizes around the theoretical values ​​of 0.11 and 0.88.

[0052] Furthermore, in-situ batch experiments across four periods revealed that the first two experimental phases showed a gradual decrease in ammonia nitrogen concentration, a gradual accumulation of nitrite nitrogen, and no excessive production of nitrate nitrogen. This indicates that appropriately increasing the aeration concentration can increase the NH4+ concentration within the system. + High conversion of -N and retention of NO3 - The production of -N is relatively low. And at 0.5–0.7 mg·L⁻¹ -1 After operating under the dissolved oxygen conditions for a period of time, NO3 appeared. - The steady increase indicates that under these dissolved oxygen conditions, anaerobic ammonia-oxidizing bacteria can simultaneously denitrify with ammonia-oxidizing bacteria. In the fourth stage, dissolved oxygen is reduced to 0.4–0.5 mg·L⁻¹. -1 NH4 within the system + The concentration of -N decreased significantly, and the production of nitrite nitrogen also decreased, with the total nitrogen removal rate reaching its highest level. This indicates that the system had reached the optimal state for synergistic denitrification by ammonia-oxidizing bacteria and anaerobic ammonia-oxidizing bacteria.

[0053] Comparative Example 1

[0054] (1) Comparative Example 1 used an upflow sludge blanket reactor (UASB) with an effective volume of 1.0 L as a control of Example 1, but without any packing material, and the dissolved oxygen (DO) concentration was maintained at a constant 0.5 mg·L throughout the process. -1 Left and right (no phased control). Inoculate with the same aerobic activated sludge as in Example 1, and maintain the influent concentration at NH4. + -N:NO2 - Using a -N=140:0 ratio, the total nitrogen in the influent is consistently controlled at 140 mg·L⁻¹. -1 To initiate short-cut nitrification-anaerobic ammonium oxidation, the influent pH is controlled at 7.0–7.5, and the hydraulic retention time (HRT) is 3 ± 0.5 h.

[0055] The simulated wastewater had the same other components as in Example 1 (including NH4Cl, KHCO3, trace elements, etc.) and was not subjected to deoxygenation treatment.

[0056] (2) Intermittently monitor NH4 in the reactor effluent weekly. + NO2 - and NO3 - The activities of AOB, NOB, and AnAOB in the sludge were measured at the same nodes as in Example 1.

[0057] The results showed that at 0.5 mg·L -1 Under constant dissolved oxygen conditions, Comparative Example 1 reactor successfully started short-cut nitrification after 70 days, with a NiAR of only 65%, far lower than the 92.2% of Example 1. Within 230 days, no significant enrichment of AnAOB was detected (Candidatus Kuenenia abundance <0.1%). After stabilization, the ammonia nitrogen removal rate was only 45±5%, the total nitrogen removal rate was 30±8%, and the effluent NO3... - -N concentration up to 40±10 mg·L -1 constant DO (0.5 mg·L) -1 It could not inhibit NOB activity (NOB activity was stable at 1.85 mg-N·g). -1 -VSS·h -1 This leads to most of NO2 being produced. - -N is oxidized to NO3. - -N, insufficient nitrite accumulation. The biomass concentration (VSS) in the reactor increased from an initial 1.496 g·L⁻¹. -1 Reduced to 0.8 g·L -1 The lack of activated carbon filler leads to severe sludge loss, the inability to stably enrich biomass, and the constant DO causes an imbalance in the microbial community, resulting in poor system stability.

[0058] The results of Comparative Example 1 indicate that constant DO cannot effectively suppress NOB, leading to a long start-up time for short-cut nitrification; the lack of packing material easily results in sludge loss, making it difficult to accumulate AnAOB, and significantly reducing denitrification efficiency and system stability. The total nitrogen removal rate is only 30±8%, and the total nitrogen removal load (NRR) is only about 35% of that achieved by dissolved oxygen gradient regulation and the synergistic effect of activated carbon.

[0059] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process, characterized in that, Includes the following steps: S1. Fill the reactor with activated carbon packing material and inoculate it with aerobic activated sludge; S2. Water is introduced into the reactor, and the concentration of ammonia nitrogen in the water is 135–145 mg·L⁻¹. -1 The concentration of nitrite nitrogen is 0 mg·L⁻¹. -1 Furthermore, the influent water was not deoxygenated; S3. Operate the reactor and perform gradient control of the reactive oxygen species concentration within the reactor in stages: Phase I: Days 0-25, maintain reactive oxygen species concentration at 0.2 < DO ≤ 0.3 mg·L⁻¹ -1 ; Phase II: Days 26–60, maintain reactive oxygen species concentration at 0.3 < DO ≤ 0.5 mg·L⁻¹ -1 ; Phase III: Days 61–150, maintain reactive oxygen species concentration at 0.5 < DO ≤ 0.7 mg·L⁻¹ -1 ; Phase IV: Days 151–230, maintain reactive oxygen species concentration at 0.4 < DO ≤ 0.5 mg·L⁻¹ -1 .

2. The method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process according to claim 1, characterized in that, In step S1, the reactor is an upflow sludge bed reactor, with its outlet connected to a secondary sedimentation tank for sludge recirculation.

3. The method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process according to claim 1, characterized in that, In step S1, the biomass concentration of the aerobic activated sludge inoculated into the reactor, based on the volatile solids concentration (VSS), is 1.496 ± 0.005 g·L⁻¹. -1 ; and / or, The dominant bacterial genus in the granular sludge after aerobic activated sludge acclimation is Candidatus Kuenenia.

4. The method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process according to claim 1, characterized in that, In step S1, the activated carbon is coconut shell activated carbon with a particle size of 8-16 mesh and a specific surface area of ​​1000-1300 m². 2 ·g -1 ; and / or, The amount of activated carbon packing is 30% to 40% of the reactor volume.

5. The method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process according to claim 1, characterized in that, In step S2, the influent is supplied using a peristaltic pump, and the total nitrogen load of the influent is 0.50–0.60 kg-N·m³. -3 ·d -1 .

6. The method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process according to claim 1, characterized in that, In step S2, the pH of the influent is controlled at 7.0 to 7.5, and the hydraulic retention time is 2.5 to 3.5 hours.

7. The method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process according to claim 1, characterized in that, In step S3, an aeration head is connected to the reactor to adjust the dissolved oxygen concentration inside the reactor through aeration treatment.

8. The method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process according to claim 1, characterized in that, In step S3, based on the volatile solids concentration (VSS), the biomass concentration of the inoculated aerobic activated sludge after successful acclimatization was 1.83 ± 0.005 g·L⁻¹. -1 .

9. The method for acclimating aerobic activated sludge to start a short-cut nitrification-anaerobic ammonium oxidation process according to claim 1, characterized in that, In step S3, in stage II, the short-cut nitrification is considered to have started successfully when the nitrite accumulation rate NiAR ≥ 90%, and in stage IV, the PN / A process is considered to have started successfully and is operating stably when the total nitrogen removal rate NRE ≥ 70%.

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