Membrane bioreactor for rapidly starting short-cut nitrification-anaerobic ammonia oxidation process and starting strategy

Abstract

The invention discloses a membrane bioreactor for rapidly starting a short-cut nitrification-anaerobic ammonia oxidation process and a starting strategy. Treatment grading, biological phase splitting and mud-membrane coexistence are one of the advantages of the membrane bioreactor. In the activated sludge, ammonia oxidizing bacteria are dominant bacteria and are mainly subjected to nitrosation reaction; and on the filler, the anaerobic ammonium oxidation bacteria are dominant and play an anaerobic ammonium oxidation role. In order to solve the problem of low mass transfer efficiency of a traditional membrane bioreactor, a stainless steel filler frame is directly welded to a stirring paddle supporting rod, and the filler frame can rotate along with a stirring paddle at the same frequency. The sponge filler is used, so that sufficient living space is provided for microorganisms, the use amount of anaerobic ammonia oxidation seed sludge when the process is started is reduced, and the starting time is shortened. The method is beneficial to solving the problems of lack of anaerobic ammonia oxidation seed sludge, difficulty in interception and enrichment of microorganisms and low mass transfer efficiency, and has huge potential and application value in treatment of high-ammonia-nitrogen industrial wastewater.

Description

Technical Field

[0001] The present invention designs an anaerobic ammonium oxidation membrane bioreactor that can treat high-ammonia nitrogen industrial wastewater, integrates a variety of sewage treatment methods, and mainly solves the problems of slow startup speed of anaerobic ammonium oxidation equipment, lack of anaerobic ammonium oxidation seed sludge, and difficulty in retaining and enriching denitrification functional bacteria. Background Art

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

[0003] Biofilm is a micro-ecosystem composed of microbial cells and their secreted extracellular polymers, which can provide sufficient attachment sites and living space for microorganisms, provide different microorganisms with different concentration gradient matrices, and protect microorganisms from environmental factors. Therefore, in response to the above challenges, the biofilm method was introduced on this basis. The biofilm method can prolong the residence time of microorganisms in the reactor through biological carriers, and achieve the enrichment and retention of functional microorganisms.

[0004] In the one-stage short-range nitrification-anaerobic ammonium oxidation process, the anaerobic ammonium oxidizing bacteria in the biofilm have a higher affinity for nitrite, which can effectively inhibit the colonization and growth of NOB in the biofilm. At the same time, anaerobic bacteria represented by anaerobic ammonium oxidizing bacteria mainly exist inside the biofilm, and aerobic bacteria represented by ammonia oxidizing bacteria exist outside the biofilm. The existence of the biofilm can not only protect the internal anaerobic bacteria from the toxic effects of oxygen, but also allow the external aerobic bacteria to make full use of oxygen, which is conducive to the smooth progress of the anaerobic ammonium oxidation reaction and the short-range nitrification reaction.

[0005] The present invention starts a one-stage short-range nitrification-anaerobic ammonium oxidation process in a completely mixed continuous flow reactor, and realizes the initial colonization of anaerobic ammonium oxidizing bacteria and ammonia oxidizing bacteria by pre-inoculating anaerobic ammonium oxidizing biological fillers with a sludge concentration of 5000-8000 mg / L and pre-adding ordinary activated sludge, thereby reducing the inoculation amount of anaerobic ammonium oxidizing sludge and shortening the start-up time of the one-stage short-range nitrification-anaerobic ammonium oxidation process; through the membrane effluent, the denitrification microorganisms are well retained in the reactor, effectively alleviating the loss of sludge. The present invention provides a theoretical basis for the efficient and stable denitrification of the one-stage short-range nitrification-anaerobic ammonium oxidation process under high ammonia nitrogen concentration, provides valuable experience for the rapid start-up and stable operation of the process, and paves the way for the wide application and promotion of the process in engineering. Summary of the invention

[0006] The present invention discloses a membrane bioreactor for rapid start-up of a short-range nitrification-anaerobic ammonium oxidation process, and describes its start-up strategy in detail. "Treatment classification, biological phase separation, and mud-film coexistence" is one of the advantages of the membrane bioreactor. In the activated sludge, ammonia oxidizing bacteria are dominant, and nitrite reaction mainly occurs; while on the filler, anaerobic ammonium oxidizing bacteria are dominant, and anaerobic ammonium oxidation is mainly played. In view of the problem of low mass transfer efficiency of traditional membrane bioreactors, the present invention directly welds the filler frame to the stirring paddle support rod, and adopts a reduction motor that can be rotated at a low speed. When the reactor is running, the filler frame drives the sponge filler to rotate at the same speed as the stirring paddle support rod, and the biofilm is in full contact with the matrix and nutrients without dead angles, and the rapid replacement of the biofilm can be achieved by adjusting the speed of the filler frame, while ensuring the efficient denitrification of the system, the mass transfer efficiency of the matrix and nutrients is improved. In addition, the sponge filler can provide sufficient attachment space and a suitable living environment for denitrification functional bacteria of different metabolic types, which is conducive to the rapid growth and reproduction of bacteria. Since the filler can enrich a large number of ammonia oxidizing bacteria and anaerobic ammonia oxidizing bacteria in a short period of time, on the one hand, it solves the problems of lack of anaerobic ammonia oxidizing seed sludge and difficulty in retaining and enriching microorganisms, and at the same time creates favorable conditions for shortening the startup time of the reactor.

[0007] A membrane bioreactor for rapid startup of a short-range nitrification-anaerobic ammonium oxidation process of the present invention is characterized by:

[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 reduction motor (1.7), a stirring paddle support rod (1.8), a stainless steel filler rack / stirring paddle (1.9), an aeration plate (1.10), a WTW Multi 3420DO / 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).

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

[0010] A membrane bioreactor for quickly starting a one-stage short-range nitrification-anaerobic ammonium oxidation process in high-ammonia nitrogen industrial wastewater comprises the following steps:

[0011] (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 is preferably 10-30%. Inoculate the reactor (1) with suspended anaerobic ammonium oxidation sludge with a sludge concentration of 5000-8000 mg / L. The influent of the reactor (1) is laboratory artificial ammonium hydrogen, ammonium chloride or ammonium sulfate to provide ammonia nitrogen for the influent, 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 simulated wastewater for bacterial growth and reproduction, which can be used as nutrients necessary for carbonation. 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 -1EDTA·2Na, 0.014mg / L H3BO3, 0.99mg / L MnCl2·4H2O, 0.25mg / LCuSO4·5H2O, 0.43mg / L ZnSO4·7H2O, 0.20mg / L NiCl2·6H2O, 0.24mg / L CoCl·6H2O, 0.18mg / L KI, 0.22mg / L Na2MoO4·2H2O, 0.05mg / L Na2WO4·2H2O; the composition and concentration of mineral elements are: 56.5mg / LCaCl2·2H2O, 300mg / L MgSO4·7H2O, 100mg / L KH2PO4.

[0012] During the pre-breeding 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 through the heating rod (1.13), and the system pH value is controlled between 7.0 and 8.0 through the alkaline agent. The inlet flow rate is controlled by the hydraulic retention time, and the inlet ammonia nitrogen volume load is controlled at 0.1 to 0.2 kg-N / m according to the inlet ammonia nitrogen concentration and the effective tank capacity. 3 ·d. The air pump is used for continuous aeration for 24 hours, and the gas is continuously input into the reactor (1) through the gas flow meter (1.15) and the aeration plate (1.10). The 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. When the surface of the filler is covered with a layer of reddish-brown biofilm, the microbial pre-colonization is considered to be successful.

[0013] (2) Start-up phase II: Before starting the reactor (1), all the suspended sludge in the reactor (1) is first discharged, and the filler with biofilm is retained on the stainless steel filler rack (1.9) in the reactor. Then, the reactor (1) is inoculated with activated sludge at a sludge concentration of 5000-8000 mg / L. The substrate and nutrient solution are continuously pumped into the reactor by continuous inlet and outlet. The speed of the stirring paddle (1.6) is set to 10-30 r / min, the inlet ammonia nitrogen concentration is 400-600 mg / L, the temperature is 30-35°C, the pH value is 7.0-8.0, and the DO concentration is 0.05-0.20 mg / L. At the initial start-up of the reactor (1), according to the inlet ammonia nitrogen concentration and the effective tank capacity, the total nitrogen volumetric load of the inlet is controlled at 0.1-0.2 kg-N / m 3·d, and the aeration volume and DO concentration are regulated by the gas flow meter (1.15). During the startup process, each time the parameters are adjusted, a gradual adjustment method should be adopted, and the adjustment should not be too large or too frequent. When the effluent ammonia nitrogen concentration is higher than 150mg / L, the aeration volume needs to be increased; when the effluent ammonia nitrogen concentration is lower than 100mg / L, the hydraulic retention time needs to be shortened to increase the inlet flow rate. Since 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 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 stabilized at 75% and 0.5kg-N / m 3 ·d or more, the one-stage short-range nitrification-anaerobic ammonium oxidation process can be considered to have been successfully started.

[0014] (3) Actual operation process: After the reactor is successfully started, the actual wastewater can be treated. The present invention is mainly used to treat actual high ammonia nitrogen wastewater with an ammonia nitrogen concentration of 200 to 2000 mg / L and a COD concentration of less than 200 mg / L. During actual operation, the system temperature should be controlled between 30 and 35°C, the pH value should be controlled between 7.0 and 8.0, the DO concentration should be controlled between 0.05 and 0.20 mg / L, and the ammonia nitrogen volume load should be controlled within 1.5 kg·m-3·d-1. At the same time, the upper and lower floating ranges of the reactor influent ammonia nitrogen concentration and the influent ammonia nitrogen volume load within 1 day should not exceed 20% of their initial values. If the inlet ammonia nitrogen concentration increases to between 20% and 50% of the initial concentration within 1 day, the hydraulic retention time shall be extended to control the fluctuation value of the inlet ammonia nitrogen volumetric load to be less than 20% within 1 day; if the inlet ammonia nitrogen concentration increases to more than 50% of the initial concentration within 1 day, the water inlet shall be stopped immediately, and ammonia nitrogen shall be provided to the system through artificial water distribution during this period to control the fluctuation value of the ammonia nitrogen volumetric load before and after the water stop to be less than 20%; if the inlet ammonia nitrogen concentration drops to below 20% of the initial concentration within 1 day, the hydraulic retention time shall be appropriately shortened to keep the fluctuation value of the inlet ammonia nitrogen volumetric load and the initial load less than 20%.

[0015] (4) Biofilm renewal: During the startup and actual operation of the reactor (1), the biofilm on the filler will experience normal aging and death. If not cleaned in time, it will seriously affect the mass transfer rate of the matrix and nutrients in the system. If the ammonia nitrogen concentration in the system effluent rises to more than 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 aged biofilm and promote metabolism. The flushing time is 5 to 10 minutes, thereby providing sufficient growth space for the growth and reproduction of new biofilms. In addition, if the filler with biofilm is removed for testing during the test, new blank filler should be added in time at the corresponding position to avoid a reduction in the filling ratio that affects the denitrification performance of the reactor (1).

[0016] The reactor innovatively uses a variable speed rotating stainless steel packing rack (1.9), which can fix the packing and also act as a stirring paddle to promote uniform mixing of the matrix and nutrient solution, thereby improving the mass transfer efficiency of the system while ensuring efficient denitrification.

[0017] The stirring motor used in the present invention has a rotation speed between 10 and 30 r / min. The slower rotation speed can provide a lower hydraulic shear force, providing favorable conditions for the rapid biofilm formation of bacteria. A stainless steel filler frame (1.9) is welded on the stirring paddle support rod (1.8). The filler frame rotates at the same frequency as the stirring paddle support rod. The lower rotation speed greatly reduces the destructive effect of the hydraulic shear force on the biofilm.

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

[0019] The present invention has the following advantages:

[0020] (1) "Treatment grading, biological phase separation, and mud-film coexistence" is one of the advantages of the membrane bioreactor. In the activated sludge, ammonia oxidizing bacteria are dominant and mainly undergo nitrite reaction; while on the filler, anaerobic ammonia oxidizing bacteria are dominant and mainly play the role of anaerobic ammonia oxidation.

[0021] (2) The present invention uses a sponge filler, which has the advantages of a larger specific surface area and a faster biofilm formation speed. It can enrich a large number of ammonia oxidizing bacteria and anaerobic ammonia oxidizing bacteria in a short period of time, solving the problems of lack of anaerobic ammonia oxidizing seed mud and difficulty in intercepting and enriching microorganisms, which is conducive to shortening the start-up time of the reactor. At the same time, a low-speed variable-speed rotating filler rack and a reduction motor are selected to improve the mass transfer efficiency of the system while ensuring efficient denitrification.

[0022] (3) In terms of startup strategy, the blank filler is pre-colonized by adding anammox suspended sludge in advance, and the anammox biofilm filler is pre-colonized to achieve rapid colonization of anammox bacteria on the blank filler. Ultimately, a one-stage short-range nitrification-anammox process can be quickly started and operated efficiently and stably with a relatively low anammox sludge inoculation amount. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Yes: Schematic diagram of the structure of a membrane bioreactor.

[0024] Figure 1In: 1 - reactor, 1.1 - including water inlet bucket, 1.2 - water outlet bucket, 1.3 - water inlet peristaltic pump, 1.4 - water outlet peristaltic pump, 1.5 - ultrafiltration membrane, 1.6 - ultrafiltration membrane fixing device, 1.7 - reduction motor, 1.8 - stirring propeller support rod, 1.9 - stainless steel packing rack / stirring propeller, 1.10 - aeration plate, 1.11 - WTW Multi3420DO / pH meter, 1.12 - DO / pH probe, 1.13 - heating rod, 1.14 - reactor water inlet, 1.15 - gas flow meter and 1.16 - air pump. DETAILED DESCRIPTION

[0025] The following describes the implementation scheme of the present invention in conjunction with the accompanying drawings and examples:

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

[0027] 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 reduction motor (1.7), a stirring paddle support rod (1.8), a stainless steel filler rack / stirring paddle (1.9), an aeration plate (1.10), a WTW Multi 3420DO / 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).

[0028] The substrate and nutrient solution in the water inlet bucket (1.1) enter the reactor through the water inlet peristaltic pump (1.3) and the reactor water inlet (1.14), and the suspended sludge, substrate and nutrient solution are evenly distributed in the reactor (1) under the action of the stirring paddle (1.9); 3 to 6 stainless steel filler racks (1.9) are welded on the stirring paddle support rod (1.8), and each stainless steel filler rack (1.9) has a plurality of holes for placing fillers. The reduction motor (1.7) is a specially customized low-speed motor, and its speed can be set to 10 to 30 r / min; the ultrafiltration membrane (1.5) is fixed in the reactor through the ultrafiltration membrane fixing device (1.6); the aeration disk (1.10) is used to provide oxygen.

[0029] Membrane bioreactors such as Figure 1As shown. The reactor (1) is built with a stainless steel porous filler rack, and blank fillers are inserted into the holes, and the filler filling ratio is preferably 10-30%. The matrix and nutrient solution in the water inlet bucket (1.1) are pumped into the reactor by the water inlet peristaltic pump (1.3), and the mud-water mixture is evenly distributed in the system under the action of the stirring paddle (1.9) and quickly filled with fillers. The treated wastewater flows into the water outlet bucket (1.2) through the ultrafiltration membrane (1.5) membrane assembly under the action of the water outlet peristaltic pump (1.4).

[0030] The specific steps are as follows:

[0031] (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 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 simulated wastewater artificially prepared in the laboratory, and ammonia nitrogen is provided to the influent through 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, 0.014mg / L H3BO3, 0.99mg / L MnCl2·4H2O, 0.25mg / LCuSO4·5H2O, 0.43mg / LZnSO4·7H2O, 0.20mg / L NiCl2·6H2O, 0.24mg / L CoCl·6H2O, 0.18mg / L KI, 0.22mg / LNa2MoO4·2H2O, 0.05mg / L Na2WO4·2H2O; the composition and concentration of mineral elements are: 56.5mg / L CaCl2·2H2O, 300mg / L MgSO4·7H2O, 100mg / L KH2PO4.

[0032] During the pre-breeding 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 through the heating rod (1.13), and the system pH value is controlled between 7.0 and 8.0 through the alkaline agent. The inlet flow rate is controlled by the hydraulic retention time, and the inlet ammonia nitrogen volume load is controlled at 0.1 to 0.2 kg-N / m according to the inlet ammonia nitrogen concentration and the effective tank capacity. 3·d. The air pump is used for continuous aeration for 24 hours, and the gas is continuously input into the reactor (1) through the gas flow meter (1.15) and the aeration plate (1.10). The 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. When the surface of the filler is covered with a layer of reddish-brown biofilm, the microbial pre-colonization is considered to be successful.

[0033] (2) Start-up phase II: Before starting the reactor (1), all the suspended sludge in the reactor (1) is first discharged, and the filler with biofilm is retained on the stainless steel filler rack (1.9) in the reactor. Then, the reactor (1) is inoculated with activated sludge at a sludge concentration of 5000-8000 mg / L. The substrate and nutrient solution are continuously pumped into the reactor by continuous inlet and outlet. The speed of the stirring paddle (1.6) is set to 10-30 r / min, the inlet ammonia nitrogen concentration is 400-600 mg / L, the temperature is 30-35°C, the pH value is 7.0-8.0, and the DO concentration is 0.05-0.20 mg / L. At the initial start-up of the reactor (1), according to the inlet ammonia nitrogen concentration and the effective tank capacity, the total nitrogen volumetric load of the inlet is controlled at 0.1-0.2 kg-N / m 3 ·d, and the aeration volume and DO concentration are regulated by the gas flow meter (1.15). During the startup process, each time the parameters are adjusted, a gradual adjustment method should be adopted, and the adjustment should not be too large or too frequent. 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. Since 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 stabilize the operation for 2 to 4 days before making further adjustments. After 45 to 90 days of startup, when the total nitrogen removal rate and total nitrogen removal load are stabilized at 75% and 0.5 kg-N / m 3 ·d or more, the one-stage short-range nitrification-anaerobic ammonium oxidation process can be considered to have been successfully started.

[0034] (3) Actual operation process: After the reactor is successfully started, the actual wastewater can be treated. The present invention is mainly used to treat actual high ammonia nitrogen wastewater with an ammonia nitrogen concentration of 200 to 2000 mg / L and a COD concentration of less than 200 mg / L. During actual operation, the system temperature should be controlled between 30 and 35°C, the pH value should be controlled between 7.0 and 8.0, the DO concentration should be controlled between 0.05 and 0.20 mg / L, and the ammonia nitrogen volume load should be controlled within 1.5 kg·m-3·d-1. At the same time, the upper and lower floating ranges of the reactor influent ammonia nitrogen concentration and the influent ammonia nitrogen volume load within 1 day should not exceed 20% of their initial values. If the inlet ammonia nitrogen concentration increases to between 20% and 50% of the initial concentration within 1 day, the hydraulic retention time shall be extended to control the fluctuation value of the inlet ammonia nitrogen volumetric load to be less than 20% within 1 day; if the inlet ammonia nitrogen concentration increases to more than 50% of the initial concentration within 1 day, the water inlet shall be stopped immediately, and ammonia nitrogen shall be provided to the system through artificial water distribution during this period to control the fluctuation value of the ammonia nitrogen volumetric load before and after the water stop to be less than 20%; if the inlet ammonia nitrogen concentration drops to below 20% of the initial concentration within 1 day, the hydraulic retention time shall be appropriately shortened to keep the fluctuation value of the inlet ammonia nitrogen volumetric load and the initial load less than 20%.

[0035] (4) Biofilm renewal: During the startup and actual operation of the reactor (1), the biofilm on the filler will experience normal aging and death. If not cleaned in time, it will seriously affect the mass transfer rate of the matrix and nutrients in the system. If the ammonia nitrogen concentration in the system effluent rises to more than 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 aged biofilm and promote metabolism. The flushing time is 5 to 10 minutes, thereby providing sufficient growth space for the growth and reproduction of new biofilms. In addition, if the filler with biofilm is removed for testing during the test, new blank filler should be added in time at the corresponding position to avoid a reduction in the filling ratio that affects the denitrification performance of the reactor (1).

[0036] The above is a specific implementation case of the present invention, which is convenient for technicians in this technical field to better understand and apply the present invention, but the implementation of the present invention is not limited to this. Therefore, simple improvements made to the present invention by technicians in this technical field are within the scope of protection of the present invention.

Claims

1. A membrane bioreactor for rapid startup of a short-range nitrification-anaerobic ammonium oxidation process, characterized in that: 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 reduction motor (1.7), a stirring paddle support rod (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 on the stirring paddle support rod (1.8), and each stainless steel filler rack (1.9) has a plurality of holes for placing fillers; the rotation speed of the stirring motor used is between 10 and 30 r / min; the ultrafiltration membrane (1.5) is fixed to the inner wall of the reactor via an ultrafiltration membrane fixing device (1.6); and the aeration disk (1.10) is used to provide oxygen.

2. A startup strategy for a membrane bioreactor for a rapid startup of a one-stage short-range nitrification-anaerobic ammonium oxidation process as claimed in claim 1, characterized in that: The following steps are involved: (1) Start-up phase I: a blank sponge filler is fixed in the hole of the stainless steel filler rack (1.9), and the filler filling ratio is preferably 10-30%; the reactor (1) is inoculated 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 can be provided to the wastewater through 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 also added to the influent to serve as nutrients necessary for bacterial growth and reproduction; wherein the components and concentrations of trace elements I in the influent are: 6.37 mg / L LEDTA·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, 0.014mg / L H3BO3, 0.99mg / L MnCl2·4H2O, 0.25mg / L CuSO4·5H2O, 0.43mg / LZnSO4·7H2O, 0.20mg / L NiCl2·6H2O, 0.24mg / L CoCl·6H2O, 0.18mg / L KI, 0.22mg / LNa2MoO4·2H2O, 0.05mg / L Na2WO4·2H2O; the composition and concentration of mineral elements are: 56.5mg / L CaCl2·2H2O, 300mg / L MgSO4·7H2O, 100mg / L KH2PO4; During the pre-breeding 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 system pH value 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 at 0.1 to 0.2 kg-N / m according to the inlet ammonia nitrogen concentration and the effective tank capacity. 3 d; the air pump is used for continuous aeration for 24 hours, and the gas is continuously input into the reactor (1) through the gas flow meter (1.15) and the aeration plate (1.10); the 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 measuring instrument (1.11); the pre-colonization time is not less than two weeks, and when the surface of the filler is covered with a layer of reddish-brown biofilm, the microorganism pre-colonization is considered to be successful; (2) Start-up phase II: Before starting the reactor (1), all the suspended sludge in the reactor (1) is first discharged, and the filler with the biofilm is retained on the stainless steel filler rack (1.9) in the reactor; then, activated sludge with a sludge concentration of 5000 to 8000 mg / L is inoculated into the reactor (1); The substrate and nutrient solution are continuously pumped into the reactor by continuous water inlet and outlet, the speed of the stirring blade (1.6) is set to 10-30 r / min, the inlet ammonia nitrogen concentration is 400-600 mg / L, the temperature is 30-35°C, the pH value is 7.0-8.0, and the DO concentration is 0.05-0.20 mg / L; at the initial start-up of the reactor (1), according to the inlet ammonia nitrogen concentration and the effective tank capacity, by adjusting the hydraulic retention time and the inlet flow rate, the inlet total nitrogen volume load is controlled to 0.1-0.2 kg-N / m 3 d, and the aeration volume and DO concentration are regulated by the gas flow meter (1.15); during the startup process, the parameter adjustment should be carried out 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 stabilized at 75% and 0.5 kg-N / m 3 ·d or more, the one-stage short-range nitrification-anaerobic ammonium oxidation process can be considered to have been successfully started.

3. The strategy according to claim 2, characterized in that It may also include: (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 and 35 °C, the pH value is controlled between 7.0 and 8.0, the DO concentration is controlled between 0.05 and 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.

4. The strategy according to claim 3, characterized in that: If the inlet ammonia nitrogen concentration increases to between 20% and 50% of the initial concentration within 1 day, the hydraulic retention time shall be extended to control the fluctuation value of the inlet ammonia nitrogen volumetric load to be less than 20% within 1 day; if the inlet ammonia nitrogen concentration increases to more than 50% of the initial concentration within 1 day, the water inlet shall be stopped immediately, and ammonia nitrogen shall be provided to the system through artificial water distribution during this period to control the fluctuation value of the ammonia nitrogen volumetric load before and after the water stop to be less than 20%; if the inlet ammonia nitrogen concentration drops to below 20% of the initial concentration within 1 day, the hydraulic retention time shall be appropriately shortened to keep the fluctuation value of the inlet ammonia nitrogen volumetric load and the initial load less than 20%.

5. The strategy according to claim 2, characterized in that It may also include: During the start-up and actual operation of the reactor (1), the biofilm on the filler will experience normal aging and death. If the ammonia nitrogen concentration in the system effluent rises to more than 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 aged biofilm and promote metabolism. The flushing time is 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 at the corresponding position.

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