SNADF efficient biological denitrification device and method based on endogenous biomass fermentation

Abstract

The present application relates to the technical field of biological denitrification, and particularly relates to a SNADF efficient biological denitrification device and method based on endogenous biomass fermentation. The specific technical scheme is as follows: (1) in the reactor, sewage and livestock and poultry wastewater are added, after starting the short-cut nitrification process, the dissolved oxygen is controlled at 0.3-0.5 mg / L, the pH is 7.5-8.0, and the total nitrogen removal rate of the reactor is higher than 85%; (2) the C / N ratio is adjusted to 0-0.1, the temperature is adjusted to 20-25 DEG C, the HRT is adjusted to 48-60 h, and the starvation strategy time is 36-48 h; after the starvation strategy, the C / N ratio is restored to 1-1.5, the temperature is restored to 30-35 DEG C, the HRT is restored to 16-20 h, and the recovery period is 48-60 h; during the implementation of the starvation strategy, the ammonia nitrogen in the reactor effluent should not be higher than 50 mg / L, the nitrite concentration should not be higher than 20 mg / L, and the total nitrogen removal rate of the reactor is higher than 93%. The present application takes the endogenous biomass such as extracellular polymeric substance (EPS) as the fermentation substrate, realizes the SNADF process in the reactor, and can simultaneously realize high-level denitrification, sludge reduction performance and low-energy-consumption operation.

Description

Technical Field

[0001] This invention relates to the field of biological denitrification technology, specifically to a high-efficiency biological denitrification device and method based on endogenous biomass fermentation (SNADF). Background Technology

[0002] With the rapid development of animal husbandry and aquaculture, livestock and poultry wastewater has become a major non-point source of nitrogen pollution in regional environments. Since livestock wastewater consistently contains high concentrations of ammonia nitrogen, organic matter, and antibiotics, developing an effective and economical advanced treatment technology for livestock wastewater is crucial for environmental protection and the sustainable development of the livestock industry.

[0003] In commonly used wastewater treatment processes for livestock farms, anaerobic treatment is typically the first step, resulting in wastewater with a typical low C / N ratio. The most common processes include primary sedimentation tanks, anaerobic digesters, conditioning tanks, anaerobic tanks, aerobic aeration tanks, anoxic tanks, and sedimentation tanks. However, traditional biological nitrification-denitrification technologies for treating pig farm wastewater have drawbacks such as high equipment investment, high energy consumption, high operating costs, and large land requirements.

[0004] Anammox is an autotrophic microbial process, and its mediated wastewater treatment technology is considered an effective, green, and economical process due to its low sludge production, low energy consumption, and low operating costs. Therefore, Anammox-mediated systems are a promising option for treating low C / N ratio pig farm wastewater, offering significant cost-effectiveness. Examples include short-cut nitrification-anammox (PNA) combined processes with denitrification, or simultaneous partial nitrification, anammox, and denitrification (SNAD) processes.

[0005] However, the nitrates produced during anammox limit the theoretical nitrogen removal efficiency of partial nitrification / anammox (PNA) to 89%. Combining PNA with heterotrophic denitrification via simultaneous partial nitrification, anammox, and denitrification (SNAD) can further reduce effluent nitrate concentrations. The uncertainty of organic matter addition in the SNAD process can inhibit anammox activity and cause secondary organic pollution in public water bodies, resulting in unstable nitrogen removal efficiency and increased operating costs. Therefore, combining fermentation with anammox to form a short-cut nitrification, anammox, denitrification, and fermentation (SNADF) process provides a new approach for low-energy, high-efficiency nitrogen removal. However, this process requires the coordinated operation of multiple units to complete nitrogen removal, increasing operational complexity. Furthermore, to maintain the continuous fermentation process in the nitrogen removal system, exogenous fermentation substrates need to be constantly replenished, which undoubtedly increases operational difficulty and costs. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a high-efficiency biological denitrification device and method based on endogenous biomass fermentation (SNADF). Using endogenous biomass such as extracellular polymeric substances (EPS) as fermentation substrates, the SNADF process is implemented in a reactor, which can simultaneously achieve high-level denitrification and sludge reduction performance as well as low-energy operation.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] This invention discloses a highly efficient biological denitrification method for SNADF based on endogenous biomass fermentation, comprising the following steps:

[0009] (1) Start-up of short-cut nitrification / anaerobic ammonium oxidation process

[0010] After adding sewage and livestock wastewater to the reactor and starting the short-cut nitrification process, before inoculating Anammox granular sludge, the concentrations of ammonia nitrogen and nitrite in the effluent are controlled at 80-150 mg / L with a ratio close to 1:1, dissolved oxygen is controlled at 0.3-0.5 mg / L, pH is controlled at 7.5-8.0, and the total nitrogen removal rate of the reactor is higher than 85%, indicating that the short-cut nitrification / anaerobic ammonium oxidation process has been successfully started.

[0011] (2) Start-up of carbon-self-sufficient SNADF process was achieved by selectively enriching fermentation strains OLB8 and Pedosphaeraceae using a starvation strategy.

[0012] The C / N ratio was adjusted to 0–0.1, the temperature to 20–25°C, the HRT to 48–60 h, and the starvation strategy duration to 36–48 h. After the starvation strategy, the C / N ratio was restored to 1–1.5, the temperature to 30–35°C, the HRT to 16–20 h, and the recovery period to 48–60 h. This process selectively eliminated Anaerolineaceae bacteria that use influent organic matter as a metabolic substrate by stopping the carbon source supply, and enriched OLB8 bacteria and Pedosphaeraceae bacteria that use endogenous organic matter (such as extracellular polymers and cell lysis products) as metabolic substrates.

[0013] Subsequently, a starvation strategy was implemented, repeated 3 to 5 times. During this period, dissolved oxygen was controlled at 0.02 to 0.1 mg / L, and oxidation-reduction potential was controlled at -50 mV to -200 mV. During the implementation of the starvation strategy, the ammonia nitrogen in the reactor effluent should not exceed 50 mg / L, the nitrite concentration should not exceed 20 mg / L, and the total nitrogen removal rate of the reactor should be higher than 93%, which means that the carbon self-sufficient SNADF process was successfully started up.

[0014] (3) Stable operation of denitrification and fermentation processes based on dissolved oxygen feedback regulation mechanism

[0015] Continuous aeration was used when the dissolved oxygen concentration was between 0.01 and 0.05 mg / L, and intermittent aeration (5 minutes of aeration followed by 5 minutes of settling) was used when the dissolved oxygen concentration was between 0.05 and 0.1 mg / L. Aeration was stopped when the dissolved oxygen concentration exceeded 0.1 mg / L, thus achieving targeted enrichment of different functional microorganisms in different types of sludge. During operation, Candidatus Kuenenia was enriched in granular sludge at a relative abundance of not less than 20%; OLB8 was enriched in flocculent sludge at a relative abundance of not less than 5%; and SJA-28 was enriched in biofilm at a relative abundance of not less than 10%.

[0016] Preferably, in step (1), the free ammonia is maintained at 20-30 mg / L, the dissolved oxygen is maintained at 1-2 mg / L, and the pH is controlled at 6.8-8.5, that is, the short-cut nitrification process is successfully started.

[0017] Preferably, the short-cut nitrification process is started by inoculating the reactor with recycled sludge from the secondary sedimentation tank, with an initial sludge concentration of 4–5 g MLSS / L; during the start-up phase of the short-cut nitrification process, the influent ammonia nitrogen is controlled at 150–250 mg / L; after the short-cut nitrification process is successfully started, the proportion of wastewater influent is reduced by 10% every 5–10 days until it reaches zero, and the influent ammonia nitrogen concentration is 800–900 mg / L.

[0018] Preferably, in step (1), the concentration of Anammox granular sludge inoculated is 3-4 g MLSS / L; after the short-cut nitrification / anaerobic ammonium oxidation process is started, the wastewater influent ratio is reduced by 10% every 5-15 days until it reaches zero; during the period of reducing the wastewater influent ratio, the effluent ammonia nitrogen concentration is maintained at 20-50 mg / L and the nitrite concentration is maintained at 10-30 mg / L; after the reactor has treated 100% of the livestock and poultry wastewater, the effluent ammonia nitrogen concentration is controlled to maintain at 10-20 mg / L and the nitrite concentration is maintained at 0-10 mg / L; during the operation of the short-cut nitrification / anaerobic ammonium oxidation process, the dissolved oxygen is maintained at 0.1-0.3 mg / L.

[0019] Preferably, in step (2), during the operation of the carbon self-supplied SNADF process, the C / N ratio is adjusted to 0.1 to 0.3, the temperature is maintained at 32 to 35°C, the HRT is maintained at 12 to 18 hours, the dissolved oxygen is maintained at 0.02 to 0.08 mg / L, and the oxidation-reduction potential is controlled at -0 mV to -200 mV; the effluent concentration is maintained at 0 to 15 mg / L for ammonia nitrogen and 0 to 5 mg / L for nitrite.

[0020] Accordingly, an apparatus for a high-efficiency biological denitrification method for SNADF based on endogenous biomass fermentation includes a reactor, which is fed by a sewage pump and a livestock wastewater pump, and discharged by an effluent pump connected to a membrane module. A screw blower equipped with a first air flow meter is connected to a disc aerator. The reactor is equipped with a biofilm carrier, a liquid level sensor and a heater.

[0021] Preferably, the top of the reactor is provided with a gas collection hood, and the bottom of the membrane module is provided with a membrane flushing module, the membrane flushing module being connected to a circulating fan equipped with a second air flow meter.

[0022] Preferably, a spray defoaming mechanism is provided above the membrane module inside the reactor, and the spray defoaming mechanism is connected to the circulating fan through a third air flow meter.

[0023] Preferably, the biofilm carrier is a hollow carrier sphere, and the hollow carrier sphere contains 8 to 10 polyurethane sponge carriers.

[0024] The present invention has the following beneficial effects:

[0025] 1. A method for targeted cultivation of OLB8 and Pedosphaeraceae fermentation strains based on a carbon-source-limited starvation strategy. This invention can start up a carbon-supplied SNADF denitrification system in 8-14 days. The ability of fermentation microorganisms to degrade complex organic matter is enhanced under starvation conditions. When easily degradable organic matter in the reactor is depleted, recalcitrant organic matter can be utilized as a carbon source by the corresponding degrading bacteria. Therefore, by controlling the carbon source supply, under starvation conditions after the carbon source supply stops, Anaerolineaceae bacteria that use influent organic matter as a metabolic substrate can be selectively eliminated, reducing competition from non-target strains, and ultimately enriching OLB8 and Pedosphaeraceae bacteria that use endogenous organic matter (such as extracellular polymers and cell lysis products) as metabolic substrates. Furthermore, acid-producing bacteria and methanogens differ greatly in growth, substrate utilization, and sensitivity to environmental changes. Compared to acid-producing bacteria, methanogens require a longer lag phase after starvation. An imbalance between the production and consumption rates of acidification products often leads to acid accumulation and loss of methanogenic activity. Therefore, starvation operations can control the fermentation process at the acid-producing stage, converting endogenous biomass into a usable carbon source to support denitrification and avoid carbon source loss due to methanogenesis.

[0026] 2. Compared to traditional nitrification-denitrification processes, the carbon-supplied SNADF process reduces aeration energy consumption by 60%, carbon source addition by 100%, and waste sludge treatment costs by 98%, resulting in extremely low operating costs. The operating costs of traditional nitrification-denitrification processes mainly include aeration, external organic matter addition, and waste sludge treatment. Considering that the PN process can save 25% of oxygen demand, the SNADF process can save 60% of aeration energy consumption. In the carbon-supplied SNADF process, the fermentation process promotes the conversion and utilization of endogenous biomass, thereby eliminating 100% of the need for external organic matter. Furthermore, the carbon-supplied SNADF process can reduce waste sludge production by 90% through fermentation. Considering that the sludge production of the PNA process is only about 15% of that of traditional biological nitrogen removal processes, the sludge production of the carbon-supplied SNADF process is about 1.5% of that of traditional processes, achieving near-zero waste sludge discharge. Traditional processes remove 1 mg / L NH4 + -N, consuming 0.890 mg / L COD and 1.12 mg / L O2, producing 0.596 mg VSS sludge. The carbon-source-supplied SNADF process removes 1 mg / L NH4. + -N requires only 0.448 mg / L O2 to produce 0.008 mg VSS sludge.

[0027] 3. The carbon-supplied SNADF process boasts highly efficient and stable nitrogen removal, extremely low residual sludge discharge, and simple operation. Although the PNA process can achieve high nitrogen removal loads under high activity and high MLVSS conditions, TNRE is limited to 89% due to effluent nitrate levels. Especially in the treatment of high-nitrogen wastewater (aquaculture wastewater, landfill leachate, etc.), the poor effluent quality caused by nitrate residue remains an obstacle to the engineering application of anaerobic ammonia oxidation processes. The carbon-supplied SNADF process utilizes in-situ fermentation products as a carbon source to support nitrate removal, thereby improving TNRE and reducing residual sludge production in the nitrogen removal system. Under similar influent loads and ΔCOD / TN conditions, the SNADF process reduces effluent nitrate by 40–50 mg / L compared to the PNA process, resulting in a corresponding 9.5% increase in TNRE. The residual sludge production of the carbon-supplied SNADF process is only one-tenth that of the PNA process. Furthermore, conventional SNAD processes require real-time maintenance of organic matter concentration within a suitable range to achieve a balance between AnAOB and denitrifying bacteria during actual operation. The carbon-supplied SNADF process omits the carbon source addition process, thus avoiding the risk of system instability caused by interspecies competition among functional microorganisms.

[0028] 4. Based on the dissolved oxygen feedback regulation mechanism, the collaborative relationships among functional microorganisms in different forms of sludge (flocs, granules, biofilms) in the carbon-source-supplied SNADF process ensure the stable operation of the SNADF process. Different forms of sludge provide different physical and chemical environments for the collaboration between anaerobic ammonia-oxidizing bacteria and other functional microorganisms. Under the morphologies of flocs, granules, and biofilms, the microbial community can effectively cooperate and metabolically couple under the support of spatial and nutrient conditions, promoting various reactions in the nitrogen cycle and improving the removal efficiency of organic matter and nitrogen in the sludge. An automatic dissolved oxygen control strategy is implemented to provide dissolved oxygen while amplifying the differences in oxygen transfer among different types of sludge, achieving the targeted enrichment of different functional microorganisms in different types of sludge. Ammonia-oxidizing bacteria, anaerobic ammonia-oxidizing bacteria, and denitrifying bacteria are enriched in flocculent sludge, granular sludge, and biofilm sludge, respectively. Candidatus Kuenenia (anaerobic ammonia oxidizing bacteria) colonized granular sludge, with its abundance increasing from 37.3% to 43.5%, representing a 67.6-fold and 4.5-fold increase in abundance in granular sludge compared to flocculent and biofilm sludge, respectively. Nitrosomonas (ammonia oxidizing bacteria) exhibited a high abundance advantage in flocculent sludge, increasing from 7.5% to 13.2%, representing a 1.9-fold and 6.1-fold increase in abundance compared to biofilm and granular sludge, respectively. The representative denitrifying bacterium, SJA-28, enriched in biofilm sludge, increasing from 2.3% to 16.5%, representing a 1.8-fold and 3.7-fold increase in abundance compared to flocculent and granular sludge, respectively. Furthermore, fermentative bacteria were enriched in flocculent sludge. The abundance of representative bacterium OLB8 increased from 0.8% to 5.6%, and its abundance in biofilm sludge was 3.3 and 13.3 times that of flocculent sludge and granular sludge, respectively. The distribution and enrichment of functional microorganisms in different forms of sludge in the SNADF system is conducive to enhancing the cooperative relationship among various denitrification functional bacteria, thereby improving the overall effect of the wastewater treatment system.

[0029] 5. The carbon-supplied SNADF process solves the problem of insufficient carbon source in the denitrification of high ammonia nitrogen and low C / N wastewater and achieves near-zero discharge of residual sludge, with wide market application. High ammonia nitrogen and low C / N wastewater, represented by anaerobic digestion liquid from livestock farming, landfill leachate, fertilizer wastewater, and monosodium glutamate wastewater, face problems such as insufficient carbon source and low total nitrogen removal rate during biological treatment, urgently requiring efficient new biological treatment methods. The carbon-supplied SNADF process converts endogenous biomass into usable carbon source, solving the problem of insufficient carbon source in the denitrification of high ammonia nitrogen and low C / N wastewater and achieving near-zero discharge of residual sludge, which has sustainable development significance and represents a new breakthrough in biological denitrification technology research. This invention completes the start-up and operation of the carbon-supplied SNADF in a 2000L scale device, with a daily wastewater treatment capacity of up to 3000L, which has important engineering demonstration significance and provides strong evidence for its feasibility in practical applications. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the SNADF high-efficiency biological denitrification device based on endogenous biomass fermentation;

[0031] Figure 2 For the carbon self-sufficient SNADF denitrification system operation performance;

[0032] Figure 3 The change in sludge concentration of flocculent sludge during the operation of a carbon-source-supplied SNADF system;

[0033] Figure 4 Changes in sludge production after the establishment of a carbon-source-supplied SNADF system;

[0034] Figure 5 To assess the antibiotic removal performance of the carbon-source-supplied SNADF system;

[0035] In the diagram: 1. Sewage pump; 2. Livestock wastewater pump; 3. Membrane module; 4. Effluent pump; 5. Liquid level sensor; 6. First air flow meter; 7. Screw blower; 8. Disc aerator; 9. Heater; 10. Biofilm carrier; 11. Polyurethane sponge carrier; 12. Gas collection hood; 13. Circulating fan; 14. Membrane flushing module; 15. Second air flow meter; 16. Spray defoaming mechanism; 17. Spray nozzle; 18. Third air flow meter. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Unless otherwise specified, the technical means used in the implementation examples are conventional means well known to those skilled in the art.

[0038] This invention discloses a highly efficient biological nitrogen removal method for SNADF based on endogenous biomass fermentation, comprising the following steps: (1) start-up and operation of short-cut nitrification (PN) process; (2) start-up and operation of short-cut nitrification / anaerobic ammonia oxidation (PNA) process; (3) start-up and stable operation of carbon self-sufficient SNADF process based on continuous starvation strategy and dissolved oxygen feedback regulation mechanism.

[0039] The specific process is as follows:

[0040] (1) During the PN start-up process, by controlling the free ammonia (FA) and dissolved oxygen, the free ammonia was maintained at 20-30 mg / L, the dissolved oxygen was maintained at 1-2 mg / L, the pH was controlled at 6.8-8.5, and the ratio of ammonia nitrogen and nitrite concentration in the effluent was close to 1:1, that is, the short-cut nitrification (PN) process was successfully started up, and the abundance of Nitrosomonas was higher than 1%.

[0041] The process involves inoculating the reactor with recycled sludge from the secondary sedimentation tank to start the short-cut nitrification (PN) process, with an initial sludge concentration of 4–5 g MLSS / L. During the start-up phase, municipal wastewater is used to dilute the livestock wastewater, controlling the influent ammonia nitrogen concentration at 150–250 mg / L. After successful start-up, the proportion of municipal wastewater influent is reduced by 10% every 5–10 days until it reaches zero, resulting in an influent ammonia nitrogen concentration of 800–900 mg / L, meeting the load requirements for nitrite treatment of high-ammonia-nitrogen livestock wastewater. Before inoculating with Anammox granular sludge, the effluent ammonia nitrogen and nitrite concentrations from the PN process are controlled at approximately 80–150 mg / L by reducing the influent ammonia nitrogen concentration and controlling dissolved oxygen, with an effluent ammonia nitrogen to nitrite concentration ratio close to 1:1.

[0042] (2) During PNA startup, Anammox granular sludge was inoculated, with Candidatus Kuenenia as the dominant microorganism and a relative abundance exceeding 10%. A biofilm carrier was placed after inoculation. During PNA operation, dissolved oxygen was controlled at 0.3–0.5 mg / L, pH at 7.5–8.0, and the total nitrogen removal rate in the reactor was above 85%, indicating successful startup of the short-cut nitrification / anaerobic ammonium oxidation (PNA) process.

[0043] The concentration of Anammox granular sludge inoculated was 3–4 g MLSS / L. After the PNA process was started, the proportion of urban wastewater was reduced by 10% every 5–15 days until it reached zero. During the period of reducing the proportion of urban wastewater, the effluent ammonia nitrogen concentration was maintained at 20–50 mg / L and the nitrite concentration at 10–30 mg / L. After the reactor had treated 100% of the livestock and poultry wastewater, the effluent ammonia nitrogen concentration was controlled to maintain 10–20 mg / L and the nitrite concentration at 0–10 mg / L. Dissolved oxygen was maintained at 0.1–0.3 mg / L during the operation of the PNA process.

[0044] (3) A method based on a carbon source-limited starvation strategy to form targeted enrichment of fermentation strains OLB8 and Pedosphaeraceae to complete the rapid start-up of SNADF.

[0045] A method for targeted enrichment of fermentation strains: By regulating the carbon source supply, under a starved environment after the carbon source supply is stopped, Anaerolineaceae bacteria that use influent organic matter as a metabolic substrate can be selectively eliminated, reducing competition from non-target strains. This ultimately leads to the successful enrichment of OLB8 and Pedosphaeraceae bacteria that use endogenous organic matter (such as extracellular polymers and cell lysis products) as metabolic substrates. This process promotes the growth dominance of OLB8 and Pedosphaeraceae bacteria, which in turn support the growth of denitrifying bacteria (such as SJA-28, Denitratisoma, and Kapabacteriales) by generating usable carbon sources from the decomposition of endogenous organic matter, eliminating nitrate byproducts generated in the Anammox process, and completing the start-up of the SNADF process.

[0046] The starvation strategy is operated as follows: the C / N ratio is adjusted from 1-1.5 to 0-0.1, the temperature is adjusted from 30-35℃ to 20-25℃ within 1-2 hours, the HRT is adjusted from 16-20 hours to 48-60 hours, and the starvation period is 36-48 hours. After the starvation strategy, the C / N ratio is restored to 1-1.5, the temperature is restored to 30-35℃ within 1-2 hours, and the HRT is restored to 16-20 hours. The recovery period is 48-60 hours, and then the starvation strategy is repeated 3-5 times. During this period, dissolved oxygen is controlled at 0.02-0.1 mg / L, and oxidation-reduction potential is controlled between -50mV and -200mV. During the starvation strategy, the ammonia nitrogen in the reactor effluent must not exceed 50 mg / L, and the nitrite concentration must not exceed 20 mg / L. A total nitrogen removal rate of over 93% indicates successful start-up of the carbon self-sufficient denitrification and fermentation (SNADF) process.

[0047] During the operation of the denitrification and fermentation (SNADF) process, the C / N ratio is adjusted to 0.1–0.3, the temperature is maintained at 32–35℃, the HRT is maintained at 12–18h, the dissolved oxygen is maintained at 0.02–0.08 mg / L, and the oxidation-reduction potential is controlled at -0mV–-200mV; the effluent ammonia nitrogen concentration is maintained at 0–15 mg / L, and the nitrite concentration is maintained at 0–5 mg / L.

[0048] (4) Based on the dissolved oxygen feedback regulation mechanism, the ecological niche advantage of functional microorganisms in different forms of sludge (flocs, granules, biofilms) is enhanced to maintain the efficient and stable operation of the SNADF process.

[0049] The carbon-supplied SNADF process employs a parameter feedback adjustment mechanism during operation. Continuous aeration is used when dissolved oxygen concentration is between 0.01 and 0.05 mg / L, intermittent aeration (5 min aeration + 5 min settling) is used when dissolved oxygen concentration is between 0.05 and 0.1 mg / L, and aeration is stopped when dissolved oxygen exceeds 0.1 mg / L. This provides dissolved oxygen while amplifying differences in oxygen transfer among different types of sludge, enabling the targeted enrichment of different functional microorganisms in different types of sludge. During operation, Candidatus Kuenenia is maintained enriched in granular sludge at a relative abundance of no less than 20%; OLB8 is enriched in flocculent sludge at a relative abundance of no less than 5%; and SJA-28 is enriched in biofilm at a relative abundance of no less than 10%.

[0050] This invention also discloses an apparatus used in the SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation, such as... Figure 1 As shown, the reactor includes a reactor, specifically an MBR reactor. The reactor uses a wastewater pump 1 and a livestock wastewater pump 2 to pump urban sewage and high-ammonia nitrogen livestock wastewater into the reactor in a specific ratio to adjust the influent ammonia nitrogen concentration. The effluent is discharged through an effluent pump 4 connected to the membrane module 3. A level sensor 5 is installed inside the reactor to control the start and stop of the effluent flow and maintain the level at 2.00 ± 0.02 m. A screw blower 7 equipped with a first air flow meter 6 is connected to a disc aerator 8, located at the bottom of the reactor, providing dissolved oxygen and ensuring thorough mixing of sludge and wastewater. A heater 9 is installed inside the reactor to maintain the temperature at approximately 30°C during operation. In one embodiment, the reactor has a box structure with dimensions of 1m × 1m × 2.2m, and an effective volume of 2m³. 3 The pH value inside the reactor is adjusted by adding KHCO3.

[0051] Furthermore, the reactor is equipped with a biofilm carrier 10. In one embodiment, the biofilm carrier is a perforated carrier sphere with an outer plastic material, a diameter of 15 cm, and pores of 1-1.5 cm. The perforated carrier sphere contains 8-10 polyurethane sponge carriers 11. The polyurethane sponge carrier has dimensions of 3×3×3 cm and a specific surface area of ​​15000 m². 2 / m 3 Its specific gravity is 0.91 g / cm³. 3 .

[0052] Furthermore, a gas collection hood 12 is installed at the top of the reactor, and a membrane flushing module 14 is installed at the bottom of the membrane module 3. The membrane flushing module 14 is connected to a circulating fan 13 equipped with a second air flow meter 15. The air entering the reactor through the disc aerator 8 becomes oxygen-deficient air after the sludge consumes oxygen. This oxygen-deficient air is then supplied to the membrane flushing module 14 by the circulating fan 13 and passes through the second air flow meter 15 to alleviate MBR membrane fouling. The flushing air volume to effluent volume is controlled at 15-20:1.

[0053] Furthermore, to prevent the accumulation of air bubbles on the surface of the reactor from interfering with the level sensor 5's level recognition, a spray defoaming mechanism 16 is installed above the membrane module 3 inside the reactor. This spray defoaming mechanism 16 is connected to the circulating fan 13 via a third air flow meter 18. The pipe diameter of the air-lift spray defoaming mechanism 16 is 4–8 cm, and the gas source is oxygen-deficient air provided by the circulating fan 13. The gas-water mixture is sprayed from the spray nozzles 17 on the pipe, and the spray flow rate is controlled by the third air flow meter 18, with the air flow rate controlled at 1–2 m³ / s. 3 / h.

[0054] The present invention will be further described below with reference to specific embodiments.

[0055] Example 1

[0056] 1. A high-efficiency biological nitrogen removal device based on endogenous biomass fermentation (SNADF), the structure of which is as follows: Figure 1 As shown, the specific structure is as disclosed above.

[0057] The reactor is equipped with a liquid level sensor 5 to maintain the liquid level at 2.00 ± 0.02 m. During operation, the heater 9 maintains the temperature at approximately 30°C. The MBR reactor has a box-like structure with dimensions of 1m × 1m × 2.2m and an effective volume of 2m³. 3 The pH value inside the reactor is adjusted by adding KHCO3.

[0058] The biofilm carrier 10 consists of a perforated plastic sphere with a diameter of 15 cm and pores of 1.5 cm. Inside the perforated sphere are 10 polyurethane sponge carriers 11. These polyurethane sponge carriers are 3×3×3 cm in size and have a specific surface area of ​​15000 m². 2 / m 3 Its specific gravity is 0.91 g / cm³. 3 .

[0059] The air entering the reactor through the disc aerator 8 becomes oxygen-deficient air after the sludge consumes oxygen. This oxygen-deficient air is then supplied to the membrane flushing module 14 by the circulating fan 13 to alleviate MBR membrane fouling. The flushing air volume to effluent volume is controlled at 20:1.

[0060] The air-lift spray defoaming mechanism 16 has a pipe diameter of 5cm. The gas source is oxygen-deficient air supplied by the circulating fan 13. The air-water mixture is sprayed out from the spray nozzle 17, and the spray flow rate is controlled by the third air flow meter 18, with the air flow rate controlled at 1.5m³ / min. 3 / h.

[0061] 2. A highly efficient biological nitrogen removal method based on endogenous biomass fermentation SNADF, the method comprising the following steps: (1) start-up and operation of short-cut nitrification (PN) process; (2) start-up and operation of short-cut nitrification / anaerobic ammonium oxidation (PNA) process; (3) rapid start-up and operation of carbon self-sufficient SNADF process under continuous starvation strategy.

[0062] Specifically: (1) During the PN start-up process, by controlling the free ammonia (FA) and dissolved oxygen, FA is maintained at 25 mg / L, dissolved oxygen is maintained at about 1.5 mg / L, pH is controlled at 7.2 to 8.2, the ratio of ammonia nitrogen and nitrite concentration in the effluent is close to 1:1, which is considered as the successful start-up of the PN process, and the abundance of Nitrosomonas is higher than 1%.

[0063] The reactor was inoculated with recycled sludge from the secondary sedimentation tank to start the PN process, with an initial sludge concentration of 4.5 g MLSS / L. During the start-up phase of the PN process, municipal sewage was used to dilute the livestock and poultry wastewater, controlling the influent ammonia nitrogen at 150 mg / L. After the PN process was successfully started up, the proportion of municipal sewage influent was reduced by 10% every 5 days until it reached zero, with the influent ammonia nitrogen concentration at 850 mg / L, meeting the load requirements for nitrification treatment of high ammonia nitrogen livestock and poultry wastewater.

[0064] Before inoculating with Anammox granular sludge, the concentrations of ammonia nitrogen and nitrite in the effluent of the PN process were controlled at around 120 mg / L by reducing the influent ammonia nitrogen concentration and controlling dissolved oxygen, with the ratio of ammonia nitrogen to nitrite concentration in the effluent close to 1:1.

[0065] (2) During PNA startup, Anammox granular sludge is inoculated, with Candidatus Kuenenia as the dominant microbial species and a relative abundance of over 10%. A biofilm carrier is placed after inoculation. During PNA operation, dissolved oxygen is controlled at approximately 0.3 mg / L, pH is controlled at 7.5–8.0, and a total nitrogen removal rate in the reactor exceeding 85% is considered a successful PNA startup.

[0066] The concentration of Anammox granular sludge inoculated was 3 g MLSS / L. After the PNA process was started, the proportion of urban sewage was reduced by 10% every 7 days until it reached zero. During the period of reducing the proportion of urban sewage, the effluent ammonia nitrogen concentration was maintained at approximately 20 mg / L and the nitrite concentration at approximately 10 mg / L. After the reactor had treated 100% of the livestock and poultry wastewater, the effluent ammonia nitrogen concentration was controlled to be maintained at approximately 15 mg / L and the nitrite concentration at approximately 5 mg / L. Dissolved oxygen was maintained at approximately 0.2 mg / L during the operation of the PNA process.

[0067] (3) The starvation strategy of the carbon-supplied SNADF process can achieve rapid and targeted enrichment of the target fermentation bacteria OLB8 and Pedosphaeraceae in the mixed microbial community. In the complex fermentation environment, multiple strains compete for substrates. The starvation environment after stopping the carbon source supply can selectively eliminate Anaerolineaceae, which uses influent organic matter as a metabolic substrate, reduce the competition from non-target bacteria, enhance the growth advantage of OLB8 and Pedosphaeraceae, which use endogenous organic matter (such as extracellular polymers and cell lysis products) as metabolic substrates, and promote the enrichment of the target bacteria. The usable carbon source generated by the decomposition of endogenous organic matter by OLB8 and Pedosphaeraceae can be used to support denitrifying bacteria (SJA-28, Denitratisoma, Kapabacteriales), eliminate nitrate byproducts generated in the Anammox process, and complete the start-up of the SNADF process.

[0068] The starvation strategy is operated as follows: the C / N ratio is adjusted from 1.2 to 0.1, the temperature is adjusted from 35℃ to 20℃ within 2 hours, and the HRT is adjusted from 16 hours to 48 hours. The starvation strategy lasts for 48 hours. After the starvation strategy, the C / N ratio is restored to 1.5, the temperature is restored to 35℃ within 2 hours, and the HRT is restored to 16 hours. The recovery period is 48 hours. The starvation strategy is then repeated 3-5 times, during which dissolved oxygen is controlled at 0.02–0.08 mg / L, and the oxidation-reduction potential is controlled at approximately -150 mV. During the starvation strategy, the ammonia nitrogen in the reactor effluent must not exceed 50 mg / L, and the nitrite concentration must not exceed 20 mg / L. A total nitrogen removal rate of over 93% in the reactor is considered a successful start-up of the carbon-self-sufficient SNADF process.

[0069] During the operation of the SNADF process, the C / N ratio was adjusted to approximately 0.25, the temperature was maintained at 32℃, the HRT was maintained at 16h, the dissolved oxygen was maintained at 0.02–0.08 mg / L, and the oxidation-reduction potential was controlled at approximately -50mV. The effluent concentration was maintained at approximately 10 mg / L for ammonia nitrogen and approximately 2 mg / L for nitrite.

[0070] (4) Based on the dissolved oxygen feedback regulation mechanism, the ecological niche advantage of functional microorganisms in different forms of sludge (flocs, granules, biofilms) is enhanced to maintain the efficient and stable operation of the SNADF process.

[0071] The carbon-supplied SNADF process employs a parameter feedback adjustment mechanism during operation. Continuous aeration is used when dissolved oxygen concentration is between 0.01 and 0.05 mg / L, intermittent aeration (5 min aeration + 5 min settling) is used when dissolved oxygen concentration is between 0.05 and 0.1 mg / L, and aeration is stopped when dissolved oxygen exceeds 0.1 mg / L. This provides dissolved oxygen while amplifying differences in oxygen transfer among different types of sludge, enabling the targeted enrichment of different functional microorganisms in different types of sludge. During operation, Candidatus Kuenenia is maintained enriched in granular sludge at a relative abundance of no less than 20%; OLB8 is enriched in flocculent sludge at a relative abundance of no less than 5%; and SJA-28 is enriched in biofilm at a relative abundance of no less than 10%.

[0072] During the operation of the SNADF process in Example 1, NO3 in the reactor influent and effluent - -N, NO2 - -N, NH4 + -N performs daily detection (e.g.) Figure 2 As shown), the operation is divided into four phases according to different operating strategies: Phase 1 (1-106 days, PN phase), Phase 2 (107-143 days, PNA start-up phase), Phase 3 (144-178 days, PNA load increase phase), and Phase 4 (184-260 days, SNADF phase).

[0073] During Phase 1, a strategy of controlling aeration volume was employed to achieve rapid start-up of the PN process within 10 days. Subsequently, the influent NH4... + -N concentration increased to 800-1000 mg / L ( Figure 2 A) To investigate the flexibility of the PN process in treating high ammonia nitrogen wastewater. During the stable operation period (24-65 days), the average influent ammonia nitrogen of the PN process was 892.4±50.6 mg / L, and NO2... - -N / NH4 + The average ratio of -N is 1.1 ± 0.2. Figure 2 (A and 2B). The results show that the PNA system can effectively reduce NH4+ in high ammonia nitrogen wastewater. + -N conversion provides a suitable substrate ratio for the Anammox process. At the end of Stage 1 (days 94-106), the NH4+ effluent from the PN process is reduced by decreasing the aeration rate. + -N and NO2 --N was controlled at 114.8±18.2 mg / L and 133.0±11.2 mg / L, respectively, to prevent high concentrations of substrate from inhibiting the activity of Anammox bacteria.

[0074] After inoculation with Anammox granular sludge in Phase 2, the PNA process was successfully started after 13 days of commissioning, with TNRE maintained above 80%. During the stable operation period (121-143 days), the average influent concentration of the PNA process was 366.6 ± 8.9 mg / L, and the effluent NH4+ concentration was... + -N, NO2 - -N, NO3 - The average concentrations of -N were 11.0 ± 8.3 mg / L, 11.5 ± 9.0 mg / L, and 23.9 ± 4.4 mg / L, respectively. During this period, NH4... + The nitrogen removal rate (NRE) and total nitrogen removal rate (TNRE) were 97.0 ± 2.3% and 87.3 ± 8.33%, respectively.

[0075] Starting from phase 3, antibiotics are added and the influent NH4 content is gradually increased. + -N concentration simulates livestock and poultry wastewater. Increasing influent NH4 in the presence of antibiotics... + During the -N concentration process, the NRE and TNRE of the PNA process were 97.6±3.3% and 88.6±2.7%, respectively, indicating that the three combined antibiotics at 2+2+2 mg / L did not inhibit the denitrification activity of PNA.

[0076] In stage 4, a starvation strategy was implemented to investigate its impact on the nitrogen removal performance of the MBR reactor. After the first starvation strategy, a large amount of ammonia nitrogen and nitrite remained in the effluent, and the TNRE decreased to 75.9%, indicating that this starvation strategy inhibited Anammox activity. Later, by reducing the influent load to maintain the reactor's nitrogen removal performance, the TNRE ultimately did not increase significantly, remaining at 85.3±4.9% (n=10). To avoid inhibiting Anammox activity, the second starvation strategy only limited COD. On day 8 after the implementation of the starvation strategy, the TNRE increased to 94.3%, indicating that this starvation strategy facilitated the rapid start-up of the SNADF nitrogen removal system. During the stable period of the SNADF system, the influent ammonia nitrogen was 828.9±11.5%, and the TNRE and ΔCOD / TN were 95.9±0.9% and 0.13±0.01, respectively. Under similar influent load and ΔCOD / TN conditions, SNADF showed a 9.5% higher TNRE than PNA.

[0077] Example 2

[0078] The SNADF high-efficiency biological denitrification device based on endogenous biomass fermentation in this embodiment is the same as in Embodiment 1.

[0079] To demonstrate the efficiency of the carbon source-limited starvation strategy for the rapid start-up of the SNADF process, the ammonia nitrogen removal rate and total nitrogen removal rate of the reactor were tested during the starvation strategy of stopping the supply of organic matter and nitrogen source and the starvation strategy of stopping the supply of carbon source only (carbon source limitation). The effectiveness of the two starvation strategies for the start-up of SNADF was compared (Table 1).

[0080] After a 6-day starvation strategy involving the withholding of organic matter and nitrogen source supply, the reactor's normal substrate supply was restored. Over the subsequent 20 days, the average total nitrogen removal rate was 84.5%, indicating that the starvation strategy involving the withholding of organic matter and nitrogen source supply was ineffective for starting up the SNADF process. After a 5-day starvation strategy involving the withholding of carbon source supply, the reactor's normal substrate supply was restored. The total nitrogen removal rate increased to 94.3% on day 8, and the average total nitrogen removal rate over the subsequent 12 days was 93.6%. This indicates that this starvation strategy facilitated the rapid start-up of the SNADF denitrification system. The results show that a starvation strategy involving only the withholding of carbon source supply (carbon source limitation) can achieve rapid start-up of the SNADF process within 8–14 days.

[0081] Table 1. Denitrification performance of the reactor after adopting the starvation strategy.

[0082]

[0083]

[0084] Example 3

[0085] The SNADF high-efficiency biological denitrification device based on endogenous biomass fermentation in this embodiment is the same as in Embodiment 1.

[0086] To demonstrate the carbon self-sufficiency and in-situ sludge reduction performance of the SNADF system, the sludge concentration of flocculent sludge was monitored during the operation of the MBR reactor (e.g., Figure 3 In Stage 2, the average sludge concentration (MLSS) of the flocculent sludge was 9.6 g / L, and showed no significant increase. As the substrate concentration increased in Stage 3, the MLSS of the flocculent sludge increased from 9.4 g / L to 10.9 g / L, reaching its highest value (12.2 g / L) after the first starvation strategy. After the second starvation strategy, the MLSS of the flocculent sludge stopped increasing and remained at 1.20 g / L. Calculations showed that after the second starvation strategy, the MLSS of the flocculent sludge stopped increasing and remained at 12.0 g / L. The sludge yield (Y) before and after the second starvation strategy was calculated. obs The concentrations were 0.197 ± 0.0388 kg MLSS / kg COD and 0.017 ± 0.012 kg MLSS / kg COD, respectively, a decrease of 11.7 times (e.g.). Figure 4 Under the same nutritional conditions, Y obsThe significant reduction in COD indicates that after the SNADF system is established, the fermenting bacteria decompose organic matter (such as EPS and BAP) in the sludge, achieving carbon self-sufficiency in the denitrification process and reducing excess sludge production by 91.5%. Based on the COD consumption values ​​of full-process and short-cut denitrification, the fermentation process can provide the SNADF system with 133.9–228.4 mg COD. Therefore, the COD-limited starvation strategy can rapidly establish a carbon self-sufficient SNADF system fermentation process and effectively improve the reactor's nitrogen removal performance.

[0087] Example 4

[0088] The SNADF high-efficiency biological denitrification device based on endogenous biomass fermentation in this embodiment is the same as in Embodiment 1.

[0089] The influent and effluent concentrations and removal rates of three antibiotics, SMX, CIP, and OTC, were studied during the operation of the SNADF system. Figure 5 As the SMX concentration increased from 0.5 mg / L to 2.0 mg / L, the removal capacity of the SNAD system for SMX gradually decreased, but the removal rate remained at 77.2 ± 2.1%. Similar to the results for SMX, the removal capacity of the SNAD system for CIP and OTC also gradually decreased with increasing antibiotic concentration, eventually maintaining removal rates of 86.1 ± 1.9% and 91.1 ± 0.9%, respectively.

[0090] Example 5

[0091] The SNADF high-efficiency biological denitrification device based on endogenous biomass fermentation in this embodiment is the same as in Embodiment 1.

[0092] To demonstrate the enhancing effects of the starvation strategy and dissolved oxygen feedback regulation mechanism on fermentation and denitrification strains, the abundance changes of functional microorganisms in sludge with different functions in the reactor were investigated. The initial stage and SNADF stage in Example 1 were named Stage 1 and Stage 2 (see Table 2). The abundance of Nitrosomonas (AOB) in flocculent sludge, biofilm sludge, and granular sludge were 4.7%–13.2%, 4.5%–6.9%, and 0.6%–2.2%, respectively, all showing an increasing trend. After the establishment of SNADF, the abundance of Candidatus_Kuenenia (AnAOB) in flocculent sludge, biofilm sludge, and granular sludge changed from 0.8%, 10.1%, and 37.3% to 0.6%, 9.6%, and 43.5%, respectively. Furthermore, AnAOB tends to colonize granular sludge more readily; in the SNADF stage, the abundance in granular sludge was 67.6 times that in flocculent sludge and 4.5 times that in biofilm sludge.

[0093] Denitrifying bacteria (DB) proliferated to varying degrees, primarily enriching in the biofilm sludge, including species such as SJA-28, Denitratisoma, and Kapabacteriales. SJA-28 showed the most significant increase, growing from 2.3% initially to 16.5% in the SNADF stage. In the light-dark feast-famine algae reactor, SJA-28 can utilize acetic acid for denitrification. Furthermore, Kapabacteriales is also considered to have the potential to utilize acetate. The proliferation of denitrifying bacteria indicates that the fermentation process within the reactor can stably generate usable carbon sources using endogenous organic matter as substrates. This stable denitrification process is one of the key reasons for the highly efficient nitrogen removal performance of SNADF.

[0094] Under a starvation strategy, OLB8, Actinomarinales, and Pedosphaeraceae, as potential fermentation species, significantly enriched in the flocculent sludge, with their abundance increasing to 6.5 times (0.8% to 5.6%), 12.5 times (0.3% to 4.0%), and 1.9 times (4.6% to 8.7%), respectively, compared to the initial stage. OLB8, as a heterotrophic bacterium, has been widely reported to possess the ability to degrade polysaccharides, proteins, and other complex molecules. However, the abundance of Anaerolineaceae, a typical hydrolytic acidifying bacterium, decreased by 11.4 times. These results indicate that in the initial stage, more organic matter flows to Anaerolineaceae, while under a starvation strategy, endogenous organic matter tends to flow to the energy metabolism pathways of species such as OLB8. Furthermore, the enrichment of fermentation bacteria promotes the rapid degradation of organic matter in the sludge, thereby reducing the production of SNADF excess sludge. Overall, under a starvation strategy, single denitrification functional species in different ecological niches are enriched, which is beneficial for strengthening synergistic cooperation among functional microorganisms and weakening substrate competition.

[0095] Table 2. Relative abundance of key functional species at the genus level in different types of sludge in the SNADF system

[0096]

[0097] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0098] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A highly efficient biological nitrogen removal method based on endogenous biomass fermentation (SNADF), characterized in that: Includes the following steps: (1) Start-up of short-cut nitrification / anaerobic ammonium oxidation process After adding wastewater and livestock wastewater to the reactor and starting the short-cut nitrification process, before inoculating Anammox granular sludge, control the concentrations of ammonia nitrogen and nitrite in the effluent to 80–150 mg / L, with a ratio close to 1:

1. During the short-cut nitrification / anaerobic ammonium oxidation operation, control the dissolved oxygen at 0.3–0.5 mg / L, the pH at 7.5–8.0, and the total nitrogen removal rate of the reactor to be higher than 85%, indicating that the short-cut nitrification / anaerobic ammonium oxidation process has been successfully started. (2) Enrichment of fermentation strain OLB8 and... through a starvation strategy Pedosphaeraceae The bacteria complete the start-up of the carbon self-sufficient SNADF process. The C / N ratio was adjusted to 0–0.1, the temperature to 20–25°C, the HRT to 48–60 h, and the starvation strategy duration to 36–48 h. After the starvation strategy, the C / N ratio was restored to 1–1.5, the temperature to 30–35°C, the HRT to 16–20 h, and the recovery period to 48–60 h. By stopping the carbon source supply, the metabolic substrates of influent organic matter were selectively eliminated. Anaerolineaceae Bacteria, enriched with OLB8 bacteria that use endogenous organic matter as a metabolic substrate and Pedosphaeraceae bacteria; Subsequently, a starvation strategy was implemented and repeated 3 to 5 times. During this period, dissolved oxygen was controlled at 0.02 to 0.1 mg / L, and oxidation-reduction potential was controlled at -50 mV to -200 mV. During the implementation of the starvation strategy, the ammonia nitrogen in the reactor effluent should not exceed 50 mg / L, the nitrite concentration should not exceed 20 mg / L, and the total nitrogen removal rate of the reactor should be higher than 93%, which means that the carbon self-sufficient SNADF process was successfully started up. (3) Stable operation of SNADF process based on dissolved oxygen feedback regulation mechanism Continuous aeration was used when the dissolved oxygen concentration was between 0.01 and 0.05 mg / L; intermittent aeration was used when the dissolved oxygen concentration was between 0.05 and 0.1 mg / L, and aeration was stopped when the dissolved oxygen concentration was higher than 0.1 mg / L, so as to achieve the targeted enrichment of different functional microorganisms. Maintain during operation Candidatus Kuenenia Enriched in granular sludge, with a relative abundance of not less than 20%; enriched OLB8 in flocculent sludge has a relative abundance of not less than 5%; enrichment SJA-28 In biofilms, the relative abundance is not less than 10%.

2. The SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation according to claim 1, characterized in that: In step (1), free ammonia is maintained at 20-30 mg / L, dissolved oxygen is maintained at 1-2 mg / L, and pH is controlled at 6.8-8.5, which means that the short-cut nitrification process is successfully started.

3. The SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation according to claim 2, characterized in that: The short-cut nitrification process was started by inoculating the reactor with recycled sludge from the secondary sedimentation tank, with an initial sludge concentration of 4–5 g MLSS / L. During the start-up phase of the short-cut nitrification process, the influent ammonia nitrogen was controlled at 150–250 mg / L. After the short-cut nitrification process was successfully started, the proportion of wastewater entering the reactor was reduced by 10% every 5–10 days until it reached zero, and the influent ammonia nitrogen concentration was 800–900 mg / L.

4. The SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation according to claim 1, characterized in that: In step (1), the concentration of Anammox granular sludge inoculated is 3-4 g MLSS / L; after the short-cut nitrification / anaerobic ammonium oxidation process is started, the wastewater influent ratio is reduced by 10% every 5-15 days until it reaches zero; during the period of reducing the wastewater influent ratio, the effluent ammonia nitrogen concentration is maintained at 20-50 mg / L and the nitrite concentration is maintained at 10-30 mg / L; after the reactor has treated 100% of the livestock and poultry wastewater, the effluent ammonia nitrogen concentration is controlled to maintain at 10-20 mg / L and the nitrite concentration is maintained at 0-10 mg / L; during the operation of the short-cut nitrification / anaerobic ammonium oxidation process, the dissolved oxygen is maintained at 0.1-0.3 mg / L.

5. The SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation according to claim 1, characterized in that: In step (2), during the operation of the carbon self-supplied SNADF process, the C / N ratio is adjusted to 0.1-0.3, the temperature is maintained at 32-35℃, the HRT is maintained at 12-18h, the dissolved oxygen is maintained at 0.02-0.08mg / L, and the oxidation-reduction potential is controlled at -0 mV--200 mV; the effluent ammonia nitrogen concentration is maintained at 0-15mg / L, and the nitrite concentration is maintained at 0-5mg / L.

6. The SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation according to any one of claims 1-5, characterized in that: The reactor is fed by a sewage pump (1) and a livestock wastewater pump (2), and discharged by an outlet pump (4) connected to a membrane module (3). A screw blower (7) equipped with a first air flow meter (6) is connected to a disc aerator (8). The reactor is equipped with a biofilm carrier (10), a liquid level sensor (5), and a heater (9).

7. The SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation according to claim 6, characterized in that: The top of the reactor is provided with a gas collection hood (12), and the bottom of the membrane module (3) is provided with a membrane flushing module (14). The membrane flushing module (14) is connected to a circulating fan (13) equipped with a second air flow meter (15).

8. The SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation according to claim 7, characterized in that: A spray defoaming mechanism (16) is provided above the membrane module (3) inside the reactor. The spray defoaming mechanism (16) is connected to the circulating fan (13) through a third air flow meter (18).

9. The SNADF high-efficiency biological denitrification method based on endogenous biomass fermentation according to claim 6, characterized in that: The biofilm carrier (10) is a hollow carrier sphere, which contains 8 to 10 polyurethane sponge carriers (11).

Images