Membrane bioreactor and start-up strategy for rapid start-up of short-cut nitrification-anammox process

Abstract

The application discloses a membrane bioreactor for quick starting of short-range nitrification-anaerobic ammonia oxidation process and a starting strategy. The membrane bioreactor has the advantages of treatment grading, biological phase separation and coexistence of sludge and membrane. In activated sludge, ammonia oxidation bacteria are dominant bacteria, and a nitration reaction mainly occurs; and in the filler, anaerobic ammonia oxidation bacteria are dominant, and anaerobic ammonia oxidation is performed. In view of the low mass transfer efficiency of a traditional membrane bioreactor, a stainless steel filler frame is directly welded to a stirring paddle support rod, and the filler frame can rotate at the same frequency as the stirring paddle. The use of sponge filler provides sufficient living space for microorganisms, reduces the use amount of anaerobic ammonia oxidation sludge during process starting, and shortens the starting time. The application is favorable for solving the problems of lack of anaerobic ammonia oxidation sludge, difficulty in interception and enrichment of microorganisms and low mass transfer efficiency, and has great potential and application value in treatment of high-ammonia-nitrogen industrial wastewater.

Description

TECHNICAL FIELD

[0001] The application designs an anaerobic ammonia oxidation membrane bioreactor capable of treating high ammonia nitrogen industrial wastewater, and combines various wastewater treatment methods, and mainly solves the problems of slow start-up speed of the anaerobic ammonia oxidation device, lack of anaerobic ammonia oxidation seed sludge, and difficulty in retaining and enriching denitrifying functional bacteria. BACKGROUND

[0002] The one-stage short-cut nitrification-anaerobic ammonia oxidation process is a new type of biological denitrification process developed by Delft University of Technology in the Netherlands in 2002 on the basis of the anaerobic ammonia oxidation process. In the process, the short-cut nitrification reaction can provide sufficient nitrite for the anaerobic ammonia oxidation reaction. Compared with the traditional biological denitrification process, the process has the advantages of energy saving and consumption reduction, carbon source saving, and low excess sludge production, and is mainly applied to the treatment of high ammonia nitrogen industrial wastewater. However, the one-stage short-cut nitrification-anaerobic ammonia oxidation process faces the following challenges in the process of engineering application: (1) lack of anaerobic ammonia oxidation seed sludge; (2) slow growth of anaerobic ammonia oxidation bacteria, and slow start-up speed of the anaerobic ammonia oxidation reactor; (3) functional bacteria (ammonia oxidation bacteria and anaerobic ammonia oxidation bacteria) are sensitive to environmental factors, and are difficult to retain and enrich.

[0003] The biofilm is a kind of micro-ecological system composed of microbial cells and extracellular polymers secreted by the cells, which can provide sufficient attachment sites and living space for microorganisms, and provide different concentrations of substrates for different microorganisms, and protect the microorganisms from environmental factors. Therefore, in view of the above challenges, the biofilm method is introduced on this basis. The biofilm method can prolong the residence time of microorganisms in the reactor through the biological carrier, and realize the enrichment and retention of functional microorganisms.

[0004] In the one-stage short-cut nitrification-anaerobic ammonia oxidation process, the anaerobic ammonia oxidation bacteria in the biofilm have higher affinity to nitrite, which can effectively inhibit the colonization and growth of NOB in the biofilm. At the same time, anaerobic bacteria represented by anaerobic ammonia oxidation bacteria mainly exist in the inside of the biofilm, and aerobic bacteria represented by ammonia oxidation bacteria exist in the outside of the biofilm, and the existence of the biofilm can not only protect the internal anaerobic bacteria from the toxic effect of oxygen, but also enable the external aerobic bacteria to fully utilize oxygen, thereby facilitating the smooth progress of the anaerobic ammonia oxidation reaction and the short-cut nitrification reaction.

[0005] The application starts a one-stage short-range nitrification-anaerobic ammonia oxidation process in a complete mixing type continuous flow reactor, realizes initial colonization of anaerobic ammonia oxidation bacteria and ammonia oxidation bacteria by pre-inoculating anaerobic ammonia oxidation biological filler with a sludge concentration of 5000-8000 mg / L and pre-adding ordinary activated sludge, so as to reduce the inoculation amount of anaerobic ammonia oxidation sludge, shorten the start-up time of the one-stage short-range nitrification-anaerobic ammonia oxidation process, and effectively alleviate sludge loss by means of membrane effluent. SUMMARY

[0006] The application discloses a membrane bioreactor for quickly starting a short-range nitrification-anaerobic ammonia oxidation process, and a start-up strategy thereof is described in detail. The membrane bioreactor has the advantages of "treatment grading, biological phase separation and coexistence of sludge and membrane", in which the ammonia oxidation bacteria are dominant in the activated sludge, and the nitrosation reaction mainly occurs; and the anaerobic ammonia oxidation bacteria are dominant on the filler, and the anaerobic ammonia oxidation mainly occurs. In view of the low mass transfer efficiency of a traditional membrane bioreactor, the application directly welds the filler frame to the stirring paddle support rod, and adopts a speed-reducing motor capable of rotating at a low speed. During the operation of the reactor, the filler frame drives the sponge filler to rotate at the same speed as the stirring paddle support rod, so that the biofilm is in full contact with the substrate and nutrients without dead angle, and the biofilm can be quickly replaced by adjusting the rotating speed of the filler frame, thereby improving the mass transfer efficiency of the substrate and nutrients while ensuring efficient denitrification of the system. In addition, the sponge filler can provide sufficient attachment space and suitable living environment for denitrifying functional bacteria of different metabolic types, which is beneficial to the rapid growth and reproduction of bacteria. Since the filler can enrich a large amount of ammonia oxidation bacteria and anaerobic ammonia oxidation bacteria in a short period of time, the problems of lack of anaerobic ammonia oxidation seed sludge, difficult microbial retention and enrichment are solved, and favorable conditions for shortening the start-up time of the reactor are created.

[0007] The membrane bioreactor for quickly starting a short-range nitrification-anaerobic ammonia oxidation process has the characteristics that:

[0008] The reactor (1) comprises a water inlet bucket (1.1), a water outlet bucket (1.2), a water inlet peristaltic pump (1.3), a water outlet peristaltic pump (1.4), an ultrafiltration membrane (1.5), an ultrafiltration membrane fixing device (1.6), a speed reducer motor (1.7), a stirring paddle support rod (1.8), a stainless steel filler frame / stirring paddle (1.9), an aeration disc (1.10), a WTW Multi 3420 DO / pH meter (1.11), a DO / pH probe (1.12), a heating rod (1.13), a reactor water inlet (1.14), a gas flow meter (1.15), and a gas pump (1.16).

[0009] The substrate and nutrient solution in the water inlet bucket (1.1) enter the reactor through the reactor water inlet (1.14) via the water inlet peristaltic pump (1.3), and the suspended sludge, substrate, and nutrient solution are uniformly distributed in the reactor (1) under the action of the stirring paddle (1.9); the stirring paddle support rod (1.8) is integrally welded with 3-6 stainless steel filler frames (1.9), and each stainless steel filler frame (1.9) has multiple holes for placing fillers. The speed of the speed reducer motor (1.7) can be set to 10-30 r / min; the ultrafiltration membrane (1.5) is fixed in the reactor by the ultrafiltration membrane fixing device (1.6); and the aeration disc (1.10) is used to provide oxygen.

[0010] A membrane bioreactor for quickly starting a one-stage short-cut nitrification-anammox process in high-ammonia-nitrogen industrial wastewater, the starting and actual operation process of which comprises the following steps:

[0011] (1) Starting stage I: the blank sponge filler is fixed in the holes of the stainless steel filler frame (1.9), and the filler filling ratio is preferably 10-30%. The reactor (1) is inoculated with suspended anammox sludge with a sludge concentration of 5000-8000 mg / L. The reactor (1) is fed with laboratory artificial hydrogen ammonium, ammonium chloride, or ammonium sulfate to provide ammonia nitrogen for the influent, and the ammonia nitrogen concentration of the influent is 400-600 mg / L. In addition, trace elements I, trace elements II, and mineral elements are added to the influent as simulated wastewater for bacterial growth and reproduction, and the necessary nutrients can be provided by carbonic acid. The components and concentrations of trace elements I in the influent are: 6.37 mg / L EDTA·2Na, 9.15 mg / L FeSO4·7H2O; the components and concentrations of trace elements II in the influent are: 19.11 mg·L -1EDTA-2Na, 0.014 mg / L H3BO3, 0.99 mg / L MnCl2-4H2O, 0.25 mg / L CuSO4-5H2O, 0.43 mg / L ZnSO4-7H2O, 0.20 mg / L NiCl2-6H2O, 0.24 mg / L CoCl-6H2O, 0.18 mg / L KI, 0.22 mg / L Na2MoO4-2H2O, 0.05 mg / L Na2WO4-2H2O; the components and concentrations of mineral elements are: 56.5 mg / L CaCl2-2H2O, 300 mg / L MgSO4-7H2O, 100 mg / L KH2PO4.

[0012] During the colonization period, the simulated wastewater with ammonia nitrogen concentration of 400-600 mg / L was pumped into the reactor (1) by the water feeding peristaltic pump (1.3), the water temperature in the reactor (1) was controlled at 30-35°C by the heating rod (1.13), and the pH value of the system was controlled at 7.0-8.0 by the alkaline agent. The influent flow was controlled by the hydraulic retention time, and the ammonia nitrogen volume loading of the influent was controlled at 0.1-0.2 kg-N / m 3 d according to the influent ammonia nitrogen concentration and the effective pool capacity. The air pump was continuously aerated for 24 h, and the air was continuously input into the reactor (1) through the gas flow meter (1.15) and the aeration disc (1.10). The DO was controlled at 0.05-0.20 mg / L, and the temperature, pH and DO concentration in the system were monitored in real time by using the portable DO / pH tester (1.11). The colonization time was not less than two weeks, and when the filler surface was covered with a layer of reddish-brown biofilm, it was considered that the microorganisms were successfully colonized.

[0013] (2) Start-up phase II: before starting the reactor (1), all the suspended sludge in the reactor (1) was discharged, and the biofilm-hung fillers were retained on the stainless steel filler frame (1.9) in the reactor. Then, the reactor (1) was inoculated with activated sludge with a sludge concentration of 5000-8000 mg / L. The substrate and nutrient solution were continuously pumped into the reactor by using the continuous water feeding and discharging mode, the stirring paddle (1.6) was set at a speed of 10-30 r / min, the influent ammonia nitrogen concentration was 400-600 mg / L, the temperature was 30-35°C, the pH value was 7.0-8.0, and the DO concentration was 0.05-0.20 mg / L. In the initial stage of starting the reactor (1), the total nitrogen volume loading of the influent was controlled at 0.1-0.2 kg-N / m 3• between d, and the aeration quantity and DO concentration are regulated by the gas flow meter (1.15). During the start-up process, when a gradual adjustment is adopted, the adjustment cannot be too large or too frequent. When the effluent ammonia nitrogen concentration is higher than 150 mg / L, the aeration quantity needs to be increased; when the effluent ammonia nitrogen concentration is lower than 100 mg / L, the hydraulic retention time needs to be shortened to increase the influent flow. Since the effluent quality has a certain lag in reflecting the parameter adjustment, after the aeration quantity or the hydraulic retention time is adjusted each time, the system needs to be stably operated for 2-4 days before the next adjustment. After the start-up process of 45-90 days, when the total nitrogen removal rate and the total nitrogen removal load are stably maintained at 75% and 0.5 kg-N / m3·d, respectively, for 5-7 consecutive days, it can be considered that the one-stage short-cut nitrification-anammox process is successfully started up. 3 • above, it can be considered that the one-stage short-cut nitrification-anammox process is successfully started up.

[0014] (3) Actual operation process: After the reactor is successfully started up, the actual wastewater can be treated. The present application is mainly used for treating the actual high-ammonia-nitrogen wastewater with an ammonia nitrogen concentration of 200-2000 mg / L and a COD concentration of less than 200 mg / L. During the actual operation, the system temperature is preferably controlled between 30-35℃, the pH value is preferably controlled between 7.0-8.0, the DO concentration is preferably controlled between 0.05-0.20 mg / L, and the ammonia nitrogen volumetric load is preferably controlled to be within 1.5 kg·m-3·d-1. At the same time, the fluctuation range of the reactor influent ammonia nitrogen concentration and the influent ammonia nitrogen volumetric load within 1 day should not be more than 20% of the initial value. If the influent ammonia nitrogen concentration is increased to between 20-50% of the initial concentration within 1 day, the hydraulic retention time is extended, and the influent ammonia nitrogen volumetric load is controlled to be lower than 20% of the fluctuation value within 1 day. If the influent ammonia nitrogen concentration is increased to more than 50% of the initial concentration within 1 day, the water supply is immediately stopped, the system is provided with ammonia nitrogen by artificial water supply during the period, and the fluctuation value of the ammonia nitrogen volumetric load before and after the water stop is controlled to be lower than 20%. If the influent ammonia nitrogen concentration is decreased to less than 20% of the initial concentration within 1 day, the hydraulic retention time is appropriately shortened, and the fluctuation value of the influent ammonia nitrogen volumetric load with the initial load is controlled to be less than 20%.

[0015] (4) Renewal of the biofilm: During the start-up and actual operation of the reactor (1), the biofilm on the filler will normally age and die. If it is not cleaned in time, it will seriously affect the mass transfer rate of the substrate and nutrients in the system. If the effluent ammonia nitrogen concentration of the system is continuously increased to more than 200 mg / L for 10 days, or the total nitrogen removal rate is continuously decreased to less than 60% for 10 days, the aeration quantity is increased to more than three times of the original aeration quantity to flush away the aged biofilm and promote metabolism, and the flushing time is 5-10 minutes, so as to provide sufficient growth space for the growth and reproduction of new biofilm. In addition, if the filler with the biofilm is taken out for detection during the test, new blank filler should be timely supplemented at the corresponding position to avoid the decrease of the filling ratio affecting the denitrification performance of the reactor (1).

[0016] The reactor is innovatively provided with a variable-speed rotating stainless steel filler frame (1.9), which can fix the filler and also serve as a stirring paddle to promote the uniform mixing of the substrate and nutrient solution, thereby improving the mass transfer efficiency of the system while ensuring efficient denitrification.

[0017] The stirring motor used in the application has a rotating speed of 10-30 r / min, and the slow rotating speed can provide a low hydraulic shear force, thereby providing favorable conditions for the rapid biofilm formation of bacteria. The stainless steel filler frame (1.9) is welded on the stirring paddle support rod (1.8), and the filler frame rotates at the same frequency as the stirring paddle support rod. The low rotating speed greatly reduces the damage of the hydraulic shear force to the biofilm.

[0018] In terms of filler selection, the sponge filler is selected. Compared with other fillers, the sponge filler has the advantages of larger specific surface area, faster biofilm formation speed and lower investment cost, thereby providing sufficient attachment sites for bacteria and improving the adaptability of denitrifying functional bacteria to different oxygen concentration gradients.

[0019] The application has the following advantages:

[0020] (1) The "treatment grading, biological phase separation and sludge film coexistence" is one of the advantages of the membrane bioreactor. In the activated sludge, ammonia-oxidizing bacteria are dominant, and the nitrosation reaction mainly occurs. On the filler, anaerobic ammonia-oxidizing bacteria are dominant, and the anaerobic ammonia oxidation effect is mainly exerted.

[0021] (2) The sponge filler is used in the application, and the sponge filler has the advantages of larger specific surface area and faster biofilm formation speed. A large amount of ammonia-oxidizing bacteria and anaerobic ammonia-oxidizing bacteria can be enriched in a short period of time, thereby solving the problems of lack of anaerobic ammonia-oxidizing seed sludge, difficulty in interception and enrichment of microorganisms, and being conducive to shortening the start-up time of the reactor. Meanwhile, the low-speed variable-speed rotating filler frame and the speed reducer motor are selected, thereby improving the mass transfer efficiency of the system while ensuring efficient denitrification.

[0022] (3) In terms of start-up strategy, the pre-deposition of anaerobic ammonia-oxidizing suspended sludge is realized to realize the pre-deposition of the blank filler and the pre-deposition of the anaerobic ammonia-oxidizing biofilm filler, so that the anaerobic ammonia-oxidizing bacteria can be rapidly deposited on the blank filler. Finally, the low anaerobic ammonia-oxidizing sludge inoculation amount is used to realize the rapid start-up and efficient and stable operation of the one-stage short-cut nitrification-anaerobic ammonia oxidation process. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a structural schematic diagram of the membrane bioreactor.

[0024] Figure 1Figure 1: Schematic diagram of the rotating biofilm-activated sludge membrane bioreactor for treating high ammonia-nitrogen industrial wastewater. 1 - reactor, 1.1 - influent tank, 1.2 - effluent tank, 1.3 - influent peristaltic pump, 1.4 - effluent peristaltic pump, 1.5 - ultrafiltration membrane, 1.6 - ultrafiltration membrane fixing device, 1.7 - speed reducer motor, 1.8 - stirring paddle support rod, 1.9 - stainless steel packing support / stirring paddle, 1.10 - aeration disc, 1.11 - WTW Multi 3420 DO / pH meter, 1.12 - DO / pH probe, 1.13 - heating rod, 1.14 - reactor influent port, 1.15 - gas flow meter and 1.16 - air pump. DETAILED DESCRIPTION

[0025] Embodiments of the present application will be described below with reference to the accompanying drawings and examples:

[0026] In Figure 1 In the embodiment shown, a plan view of a rotating biofilm-activated sludge membrane bioreactor for treating high ammonia-nitrogen industrial wastewater according to the present application is shown.

[0027] The reactor (1) comprises an influent tank (1.1), an effluent tank (1.2), an influent peristaltic pump (1.3), an effluent peristaltic pump (1.4), an ultrafiltration membrane (1.5), an ultrafiltration membrane fixing device (1.6), a speed reducer motor (1.7), a stirring paddle support rod (1.8), a stainless steel packing support / stirring paddle (1.9), an aeration disc (1.10), a WTW Multi 3420 DO / pH meter (1.11), a DO / pH probe (1.12), a heating rod (1.13), a reactor influent port (1.14), a gas flow meter (1.15) and an air pump (1.16).

[0028] The substrate and nutrient solution in the influent tank (1.1) enter the reactor via the reactor influent port (1.14) through the influent peristaltic pump (1.3), and the suspended sludge, substrate and nutrient solution are uniformly distributed in the reactor (1) under the action of the stirring paddle (1.9); the stirring paddle support rod (1.8) has 3-6 stainless steel packing supports (1.9) welded thereon, and each stainless steel packing support (1.9) has multiple holes for placing packing material. The speed reducer motor (1.7) is a specially customized low-speed motor, and its speed can be set to 10-30 r / min; the ultrafiltration membrane (1.5) is fixed in the reactor by the ultrafiltration membrane fixing device (1.6); and the aeration disc (1.10) is used to provide oxygen.

[0029] The membrane bioreactor is as shown in Figure 1The reactor (1) is provided with a stainless steel porous filler frame, and the blank filler is inserted into the holes. The filling ratio of the filler is preferably 10-30%. The substrate and nutrient solution in the water inlet bucket (1.1) are pumped into the reactor by the water inlet peristaltic pump (1.3). The sludge-water mixture is uniformly distributed in the system under the action of the stirring paddle (1.9) and quickly fills the filler. The treated wastewater flows into the water outlet bucket (1.2) through the ultrafiltration membrane (1.5) membrane module under the action of the water outlet peristaltic pump (1.4).

[0030] The specific operation steps are as follows:

[0031] (1) Start-up phase I: Fix the blank sponge filler in the holes of the stainless steel filler frame (1.9), and the filling ratio of the filler is preferably 10-30%. Inoculate the reactor (1) with suspended anaerobic ammonia oxidation sludge with a sludge concentration of 5000-8000 mg / L. The influent of the reactor (1) is laboratory-configured simulated wastewater. Ammonium bicarbonate, ammonium chloride or ammonium sulfate is used to provide ammonia nitrogen for the influent, and the ammonia nitrogen concentration of the influent is 400-600 mg / L. In addition, trace element I, trace element II and mineral element are added to the influent as necessary nutrients for bacterial growth and reproduction. The components and concentrations of trace element I in the influent are: 6.37 mg / L EDTA·2Na, 9.15 mg / L FeSO4·7H2O; the components and concentrations of trace element II in the influent are: 19.11 mg·L -1 EDTA·2Na, 0.014 mg / L H3BO3, 0.99 mg / L MnCl2·4H2O, 0.25 mg / L CuSO4·5H2O, 0.43 mg / L ZnSO4·7H2O, 0.20 mg / L NiCl2·6H2O, 0.24 mg / L CoCl·6H2O, 0.18 mg / L KI, 0.22 mg / L Na2MoO4·2H2O, 0.05 mg / L Na2WO4·2H2O; the components and concentrations of mineral elements are: 56.5 mg / L CaCl2·2H2O, 300 mg / L MgSO4·7H2O, 100 mg / L KH2PO4.

[0032] During the colonization period, the simulated wastewater with an ammonia nitrogen concentration of 400-600 mg / L is pumped into the reactor (1) by the water inlet peristaltic pump (1.3). The water temperature in the reactor (1) is controlled at 30-35°C by the heating rod (1.13), and the pH value of the system is controlled at 7.0-8.0 by an alkaline agent. The influent flow is controlled by the hydraulic retention time, and the ammonia nitrogen volumetric loading is controlled at 0.1-0.2 kg-N / m 3between 0.05 and 0.20 mg / L, and the temperature, pH and DO concentration in the system were monitored in real time using a portable DO / pH meter (1.11). The predetermined colonization time was not less than two weeks, and the microbial colonization was considered successful when the filler surface was covered with a layer of reddish-brown biofilm.

[0033] (2) Start-up phase II: Before starting the reactor (1), all suspended sludge in the reactor (1) was discharged, and the biofilm-attached filler was retained on the stainless steel filler rack (1.9) in the reactor. Then, the reactor (1) was inoculated with activated sludge with a sludge concentration of 5000-8000 mg / L. The substrate and nutrient solution were continuously pumped into the reactor using a continuous water inlet and outlet mode, the stirring paddle (1.6) was set to a speed of 10-30 r / min, the ammonia nitrogen concentration of the influent was 400-600 mg / L, the temperature was 30-35°C, the pH was 7.0-8.0, and the DO concentration was 0.05-0.20 mg / L. In the initial start-up of the reactor (1), the total nitrogen volumetric loading of the influent was controlled at 0.1-0.2 kg-N / m 3 mg / L, the aeration amount and DO concentration were adjusted through the gas flow meter (1.15). During the start-up process, when adjusting the parameters, the adjustments should be gradual and not too large or too frequent. When the effluent ammonia nitrogen concentration was higher than 150 mg / L, the aeration amount needed to be increased; when the effluent ammonia nitrogen concentration was lower than 100 mg / L, the hydraulic retention time needed to be shortened to increase the influent flow rate. Due to the lag in the effluent water quality when adjusting the parameters, after adjusting the aeration amount or hydraulic retention time, the system needed to be operated stably for 2-4 days before further adjustments were made. After 45-90 days of start-up, when the total nitrogen removal rate and total nitrogen removal loading were stable at 75% and 0.5 kg-N / m 3 above, the start-up of the one-stage short-cut nitrification-anammox process was considered successful.

[0034] (3) Actual operation process: after the reactor is successfully started, actual wastewater can be treated. The present application is mainly used for treating actual high ammonia-nitrogen wastewater with ammonia-nitrogen concentration of 200-2000 mg / L and COD concentration less than 200 mg / L. During actual operation, the system temperature is preferably controlled at 30-35℃, the pH value is preferably controlled at 7.0-8.0, the DO concentration is preferably controlled at 0.05-0.20 mg / L, and the ammonia-nitrogen volumetric loading is preferably controlled within 1.5 kg·m-3·d-1. Meanwhile, the fluctuation range of the ammonia-nitrogen concentration of the influent and the ammonia-nitrogen volumetric loading of the reactor within 1 day should not exceed 20% of the initial value. If the ammonia-nitrogen concentration of the influent is increased to 20-50% of the initial concentration within 1 day, the hydraulic retention time is prolonged, and the fluctuation value of the ammonia-nitrogen volumetric loading within 1 day is controlled to be lower than 20%. If the ammonia-nitrogen concentration of the influent is increased to more than 50% of the initial concentration within 1 day, the influent is immediately stopped, the system is provided with ammonia-nitrogen by artificial water supply during the period, and the fluctuation value of the ammonia-nitrogen volumetric loading before and after the stoppage of the influent is controlled to be lower than 20%. If the ammonia-nitrogen concentration of the influent is decreased to less than 20% of the initial concentration within 1 day, the hydraulic retention time is appropriately shortened, and the fluctuation value of the ammonia-nitrogen volumetric loading is controlled to be less than 20% of the initial loading.

[0035] (4) Renewal of the biofilm: during the start-up and actual operation of the reactor (1), the biofilm on the filler will normally age and die. If not cleaned in time, the mass transfer rate of the substrate and nutrients in the system will be seriously affected. If the ammonia-nitrogen concentration of the effluent of the system is continuously increased to more than 200 mg / L for 10 days, or the total nitrogen removal rate is continuously decreased to less than 60% for 10 days, the aeration amount is increased to more than three times of the original aeration amount to flush away the aged biofilm and promote metabolism, and the flushing time is 5-10 minutes, thereby providing sufficient growth space for the growth and reproduction of new biofilm. In addition, if the filler with biofilm is taken out for detection during the test, new blank filler should be timely supplemented at the corresponding position to avoid the decrease of the filling ratio affecting the denitrification performance of the reactor (1).

[0036] The above is a specific implementation case of the present application, which facilitates the understanding and application of the present application by the person skilled in the art, but the implementation of the present application is not limited to this. Therefore, the simple improvement of the present application made by the person skilled in the art is within the protection scope of the present application.

Claims

1. A rapid start-up short-cut nitrification-anaerobic ammonium oxidation process, characterized in that: The reactor (1) used in the process includes a water inlet bucket (1.1), a water outlet bucket (1.2), a water inlet peristaltic pump (1.3), a water outlet peristaltic pump (1.4), an ultrafiltration membrane (1.5), an ultrafiltration membrane fixing device (1.6), a reduction motor (1.7), a stirring paddle support (1.8), a stainless steel packing rack / stirring paddle (1.9), an aeration plate (1.10), a DO / pH meter (1.11), a DO / pH probe (1.12), a heating rod (1.13), a reactor water inlet (1.14), a gas flow meter (1.15) and an air pump (1.16); The substrate and nutrient solution in the water inlet bucket (1.1) enter the reactor via the water inlet peristaltic pump (1.3) and the reactor water inlet (1.14); 3 to 6 stainless steel filler racks (1.9) are welded to the stirring paddle support rod (1.8), and each stainless steel filler rack (1.9) has a plurality of holes for placing fillers; the stirring motor used has a rotation speed between 10 and 30 r / min; the ultrafiltration membrane (1.5) is fixed to the inner wall of the reactor via the ultrafiltration membrane fixing device (1.6); the aeration disk (1.10) is used to provide oxygen; It is characterized in that it includes the following steps: (1) Start-up phase I: Fix the blank sponge filler in the hole of the stainless steel filler rack (1.9), and the filler filling ratio should be 10 ~ 30%; inoculate the reactor (1) with suspended anaerobic ammonia oxidation sludge with a sludge concentration of 5000 ~ 8000 mg / L; the influent of the reactor (1) is simulated wastewater prepared artificially in the laboratory, and ammonia nitrogen is provided to the wastewater by ammonium bicarbonate, ammonium chloride or ammonium sulfate, and the influent ammonia nitrogen concentration is 400 ~ 600 mg / L; in addition, trace elements I, trace elements II and mineral elements are added to the influent to serve as nutrients necessary for bacterial growth and reproduction; among them, the components and concentrations of trace elements I in the influent are: 6.37 mg / L EDTA·2Na, 9.15 mg / L FeSO4·7H2O; the components and concentrations of trace elements II in the influent are: 19.11 mg·L -1 EDTA·2Na, 0.014 mg / L H3BO3, 0.99 mg / L MnCl2·4H2O, 0.25 mg / L CuSO4·5H2O, 0.43 mg / L ZnSO4·7H2O, 0.20 mg / L NiCl2·6H2O, 0.24 mg / L CoCl·6H2O, 0.18 mg / L KI, 0.22 mg / L Na2MoO4·2H2O, 0.05 mg / L Na2WO4·2H2O; the composition and concentration of mineral elements are: 56.5 mg / LCaCl2·2H2O, 300 mg / L MgSO4·7H2O, 100 mg / L KH2PO4; During the pre-colonization period, simulated wastewater with an ammonia nitrogen concentration of 400 to 600 mg / L is pumped into the reactor (1) through the inlet peristaltic pump (1.3). The water temperature in the reactor (1) is controlled between 30 and 35°C by the heating rod (1.13), and the pH value of the system is controlled between 7.0 and 8.0 by the alkaline agent. The inlet flow rate is controlled by the hydraulic retention time, and the inlet ammonia nitrogen volume load is controlled between 0.1 and 0.2 kg-N / m according to the inlet ammonia nitrogen concentration and the effective tank capacity. 3 d; air pump is used for continuous aeration for 24 h, and gas is continuously input into the reactor (1) through the gas flow meter (1.15) and the aeration plate (1.10); DO is controlled between 0.05 and 0.20 mg / L, and the temperature, pH and DO concentration in the system are monitored in real time using a portable DO / pH meter (1.11); the pre-colonization time is not less than two weeks, and the microbial pre-colonization is considered successful when the surface of the filler is covered with a layer of reddish-brown biofilm; (2) Start-up phase II: Before starting the reactor (1), all the suspended sludge in the reactor (1) was first discharged, and the filler with biofilm was retained on the stainless steel filler rack (1.9) in the reactor; then, the reactor (1) was inoculated with activated sludge with a sludge concentration of 5000 ~ 8000 mg / L; the substrate and nutrient solution were continuously pumped into the reactor by continuous inlet and outlet, and the rotation speed was set to 10 ~ 30 r / min, the influent ammonia nitrogen concentration was 400 ~ 600 mg / L, the temperature was 30 ~ 35℃, the pH value was 7.0 ~ 8.0, and the DO concentration was 0.05 ~ 0.20 mg / L; at the initial start-up of the reactor (1), the total nitrogen volumetric load of the influent was controlled at 0.1 ~ 0.2 kg-N / m by adjusting the hydraulic retention time and the influent flow rate according to the influent ammonia nitrogen concentration and the effective tank capacity. 3 d, and the aeration volume and DO concentration are regulated by the gas flow meter (1.15); during the startup process, parameter adjustments should be made in a step-by-step manner, and should not be adjusted too much or too frequently; when the effluent ammonia nitrogen concentration is higher than 150 mg / L, the aeration volume needs to be increased; when the effluent ammonia nitrogen concentration is lower than 100 mg / L, the hydraulic retention time needs to be shortened to increase the inlet flow rate; because the effluent water quality has a certain lag in reflecting the parameter adjustment, each time the aeration volume or hydraulic retention time is adjusted, it is necessary to run it stably for 2 to 4 days before making the next adjustment; after 45 to 90 days of startup, when the total nitrogen removal rate and total nitrogen removal load are stable at 75% and 0.5 kg-N / m3 respectively for 5 to 7 consecutive days, 3 d or more, the one-stage short-range nitrification-anaerobic ammonium oxidation process can be considered to have been successfully started.

2. The process according to claim 1, characterized in that Also includes: (3) Actual operation process: After the reactor is successfully started, it begins to treat actual wastewater; it treats actual high-ammonia nitrogen wastewater with an ammonia nitrogen concentration of 200-2000 mg / L and a COD concentration of less than 200 mg / L; during actual operation, the system temperature is controlled between 30-35°C, the pH value is controlled between 7.0-8.0, the DO concentration is controlled between 0.05-0.20 mg / L, and the ammonia nitrogen volume load is controlled at 1.5 kg·m -3 ·d -1 At the same time, the fluctuation range of the reactor inlet ammonia nitrogen concentration and the inlet ammonia nitrogen volume load within 1 day should not exceed 20% of its initial value.

3. The process according to claim 2, characterized in that: If the influent ammonia nitrogen concentration rises to between 20% and 50% of the initial concentration within one day, the hydraulic retention time should be extended to control the fluctuation value of the influent ammonia nitrogen volume load within one day to be less than 20%; if the influent ammonia nitrogen concentration rises to more than 50% of the initial concentration within one day, the water inlet should be stopped immediately, and ammonia nitrogen should be supplied to the system through artificial water distribution during this period to control the fluctuation value of the ammonia nitrogen volume load before and after the water stop to be less than 20%; if the influent ammonia nitrogen concentration drops to below 20% of the initial concentration within one day, the hydraulic retention time should be appropriately shortened and the fluctuation value of the influent ammonia nitrogen volume load and the initial load should be kept less than 20%.

4. The process according to claim 2, characterized in that Also includes: During the start-up and actual operation of the reactor (1), the biofilm on the packing will show normal aging and death; If the ammonia nitrogen concentration in the system effluent rises to above 200 mg / L for 10 consecutive days, or the total nitrogen removal rate drops below 60% for 10 consecutive days, the aeration volume should be increased to more than three times the original aeration volume to flush away the aging biofilm and promote metabolism. The flushing time should be 5 to 10 minutes. In addition, if the filler with biofilm is removed for testing during the test, new blank filler should be added in time to the corresponding position.

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