Ammonia-oxidizing sewage microbacterium, microbial agent thereof and application thereof

Abstract

The present invention relates to the field of microbial technology, and discloses a Hydrogenophaga sp. with ammonia oxidation ability, a microbial agent and its application. The strain name of the Hydrogenophaga sp. is B1, and the preservation number is CCTCC No: M 2025640. The Hydrogenophaga sp. B1 provided by the present invention can convert ammonia nitrogen into nitrite nitrogen, so as to achieve shortcut nitrification in wastewater treatment. Moreover, this strain can tolerate and effectively treat a relatively high concentration of ammonia nitrogen, and has good adaptability to different pH, salinity and temperature environments.

Description

Technical Field

[0001] The present invention relates to the field of microbial technology, and particularly to a Microbacterium aquimaris with ammonia oxidation ability, a microbial agent and its application. Background Art

[0002] The traditional biological nitrogen removal technology for ammonia nitrogen wastewater is the nitrification-denitrification process, and the specific process is as follows: ammonia nitrogen (NH4 + -N) → nitrite nitrogen (NO2 - -N) → nitrate nitrogen (NO3 - -N) → nitrite nitrogen → nitrogen gas. This process requires additional addition of a large amount of carbon source, and has high oxygen consumption and high sludge production, resulting in high operating costs and low efficiency of the wastewater treatment system.

[0003] The new short-cut nitrification technology (partial nitrification, PN) refers to that the ammonia nitrogen oxidation process only proceeds to the nitrite stage, that is, after ammonia nitrogen is oxidized to nitrite nitrogen, it is no longer further oxidized to nitrate nitrogen. Short-cut nitrification can be coupled with denitrification, and denitrifying bacteria are used to convert the nitrite nitrogen accumulated in the short-cut nitrification process into nitrogen gas; it can also be coupled with anaerobic ammonium oxidation, and under the action of anaerobic ammonium oxidizing bacteria, ammonia nitrogen and nitrite nitrogen are converted into nitrogen gas together. Compared with the traditional nitrification-denitrification process, using the short-cut nitrification technology can shorten the ammonia nitrogen oxidation process, reduce oxygen consumption and carbon source demand, and reduce the discharge amount of excess sludge, and improve the nitrogen removal efficiency of wastewater.

[0004] The key to the short-cut nitrification technology lies in controlling the reaction in the stage of stable accumulation of nitrite, and avoiding its further conversion into nitrate. The core role is played by ammonia-oxidizing bacteria (AOB), and these bacteria can convert ammonia nitrogen into nitrite nitrogen under aerobic conditions. The existing AOB strain resources are few, and the currently discovered AOB are mainly concentrated in the genera Nitrosomonas, Enterobacter and Pseudomonas, such as patents CN119662472A, CN117050895A, CN104388342A. No strain has been reported in Microbacterium aquimaris ( Aquamicrobium defluvii ) that can convert ammonia nitrogen into nitrite nitrogen. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a Microbacterium aquimaris with ammonia oxidation ability, a microbial agent and its application. The Microbacterium aquimaris B1 provided by the present invention can convert ammonia nitrogen into nitrite nitrogen, thereby realizing short-cut nitrification in wastewater treatment. Moreover, this strain can tolerate and effectively treat a higher concentration of ammonia nitrogen, and has good adaptability to different pH, salinity and temperature environments.

[0006] The specific technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides a sewage microbacterium with ammonia oxidation ability ( Aquamicrobium defluvii ), the strain name of the sewage microbacterium is B1, and the preservation number is CCTCC No: M 2025640.

[0008] The strain of the present invention is a new strain within the sewage microbacterium ( Aquamicrobium defluvii ), and its 16S rRNA sequence is shown in SEQ ID NO: 1. The preservation information is as follows:

[0009] Name of the preservation unit: China Center for Type Culture Collection (abbreviated as "CCTCC");

[0010] Address of the preservation unit: Wuhan University, China;

[0011] Preservation date: March 31, 2025;

[0012] Preservation number: CCTCC No: M 2025640.

[0013] The sewage microbacterium B1 provided by the present invention has ammonia oxidation ability and can convert ammonia nitrogen into nitrite nitrogen. When used in wastewater treatment, it can achieve short-cut nitrification. Moreover, in the presence of nitrite-oxidizing bacteria (NOB), this strain can still develop into a dominant strain under certain conditions, thereby controlling the ammonia oxidation reaction at the stage of stable accumulation of nitrite nitrogen, reducing the further oxidation of nitrite nitrogen by NOB to nitrate nitrogen, and facilitating the nitrification process to proceed in the way of short-cut nitrification.

[0014] In addition, the sewage microbacterium B1 of the present invention can tolerate a relatively high ammonia nitrogen concentration and can still achieve the conversion of ammonia nitrogen → nitrite nitrogen when the ammonia nitrogen concentration is 2000 mg / L. Moreover, it has good adaptability to different pH, salinity and temperature environments and can effectively exert its ammonia oxidation function in an environment with a pH value of 5-9, a salinity not higher than 3% and a temperature of 10-40 °C. The above characteristics make this strain have lower requirements for the quality of wastewater when used in wastewater treatment and can simplify the pre-treatment process of wastewater.

[0015] In a second aspect, the present invention provides a microbial inoculant with ammonia oxidation ability, and the microbial inoculant includes the above-mentioned sewage microbacterium.

[0016] Preferably, the microbial inoculant is a bacterial liquid or a bacterial powder.

[0017] Preferably, the microbial inoculant further includes tryptic soy broth (TSB) medium.

[0018] In a third aspect, the present invention provides a method for preparing the microbial inoculum, comprising the following steps: picking Microbacterium flavescens from sewage water, inoculating it into a tryptic soy broth liquid medium, and performing aerobic culture at 35-37°C for 3-6 days.

[0019] In a fourth aspect, the present invention provides the application of the Microbacterium flavescens from sewage water or the microbial inoculum in an ammonia oxidation reaction, and the ammonia oxidation reaction is: under the action of the Microbacterium flavescens from sewage water or the microbial inoculum, ammonia nitrogen is converted into nitrite.

[0020] Preferably, the conditions of the ammonia oxidation reaction are as follows: the initial ammonia nitrogen concentration is not higher than 2 g / L, the salinity is not higher than 3%, the temperature is 10-40°C, and the pH value is 5-9.

[0021] Furthermore, the conditions of the ammonia oxidation reaction are as follows: the salinity is not higher than 0.5%, the temperature is 20-37°C, and the pH value is 7-9.

[0022] In a fifth aspect, the present invention provides the application of the Microbacterium flavescens from sewage water or the microbial inoculum in wastewater treatment.

[0023] Preferably, the application comprises the following steps: performing shortcut nitrification treatment on the wastewater using the Microbacterium flavescens from sewage water or the microbial inoculum, and after converting the ammonia nitrogen in the wastewater into nitrite nitrogen, using denitrifying bacteria to convert the nitrite nitrogen into nitrogen gas.

[0024] Preferably, during the shortcut nitrification treatment, the dissolved oxygen concentration of the wastewater is controlled to be 0.4-0.5 mg / L, the pH value is 7-9, and the temperature is 20-37°C.

[0025] Preferably, during the shortcut nitrification treatment, sodium acetate is added to the wastewater.

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

[0027] (1) The Microbacterium flavescens B1 of the present invention can convert ammonia nitrogen into nitrite nitrogen, thereby achieving shortcut nitrification in wastewater treatment, and this is the first time to discover a strain capable of converting ammonia nitrogen into nitrite nitrogen in Microbacterium flavescens from sewage water ( Aquamicrobium defluvii )

[0028] (2) The Microbacterium flavescens B1 of the present invention has a competitive advantage over NOB and can still develop into a dominant strain in the presence of NOB, which is beneficial to the nitrification process to proceed in the way of shortcut nitrification.

[0029] (3) The Microbacterium flavescens B1 of the present invention can tolerate and effectively treat a relatively high ammonia nitrogen concentration, and has good adaptability to different pH, salinity and temperature environments. Description of the Drawings

[0030] Figure 1 It is the experimental result diagram of Aquamicrobium sp. B1 during the secondary screening of strains.

[0031] Figure 2 It is the experimental result diagram of positive control and negative control during the secondary screening of strains.

[0032] Figure 3 It shows the change of denitrification effect of Aquamicrobium sp. B1 at each stage when used for wastewater treatment. Detailed implementation manners

[0033] The present invention will be further described below in conjunction with embodiments.

[0034] First, the present invention relates to an Aquamicrobium sp. with ammonia oxidation ability ( Aquamicrobium defluvii ), the strain name of the Aquamicrobium sp. is B1, and the deposit number is CCTCC No: M 2025640. This strain is deposited in the China Center for Type Culture Collection (abbreviated as "CCTCC"), the address of the deposit unit is Wuhan University, China, the deposit date is March 31, 2025, and the 16S rRNA sequence is as shown in SEQ ID NO:1.

[0035] The above strain can convert ammonia nitrogen into nitrite nitrogen, which is the first time to find a strain with this function in Aquamicrobium sp. ( Aquamicrobium defluvii ), providing a new strain resource for the short-cut nitrification treatment of wastewater. In addition, the above strain also has the following characteristics: it has a competitive advantage relative to NOB and can still develop into a dominant strain in the presence of NOB, so as to control the ammonia oxidation reaction in the stage of stable accumulation of nitrite nitrogen, which is beneficial to the nitrification process to proceed in the way of short-cut nitrification; it can tolerate and effectively treat a relatively high ammonia nitrogen concentration, and has a good adaptability to different pH, salinity and temperature environments. Therefore, when applied to wastewater treatment, it is beneficial to reduce the requirements for wastewater quality and simplify the pre-treatment process of wastewater.

[0036] Second, the present invention relates to a microbial agent with ammonia oxidation ability, and the microbial agent includes the above-mentioned Aquamicrobium sp.

[0037] In some specific implementation manners, the microbial agent is a bacterial liquid or bacterial powder.

[0038] In some specific implementation manners, the microbial agent further includes tryptic soy broth liquid medium.

[0039] Third, the present invention relates to a method for preparing the microbial inoculum, comprising the following steps: picking Microbacterium flavescens from sewage, inoculating it into a tryptic soy broth liquid medium, and performing aerobic culture at 35-37 °C for 3-6 days.

[0040] Fourth, the present invention relates to the application of the Microbacterium flavescens or the microbial inoculum in the ammonia oxidation reaction, and the ammonia oxidation reaction is as follows: under the action of the Microbacterium flavescens or the microbial inoculum, ammonia nitrogen is converted into nitrite.

[0041] In some specific embodiments, the conditions of the ammonia oxidation reaction are as follows: the initial ammonia nitrogen concentration is not higher than 2 g / L, the salinity is not higher than 3%, the temperature is 10-40 °C, and the pH value is 5-9.

[0042] Fifth, the present invention relates to the application of the Microbacterium flavescens or the microbial inoculum in wastewater treatment.

[0043] In some specific embodiments, the application comprises the following steps: performing shortcut nitrification treatment on the wastewater using the Microbacterium flavescens or the microbial inoculum, converting the ammonia nitrogen in the wastewater into nitrite nitrogen, and then using denitrifying bacteria to convert the nitrite nitrogen into nitrogen gas. During the shortcut nitrification treatment process, the dissolved oxygen concentration of the wastewater is controlled at 0.4-0.5 mg / L, the pH value is 7-9, the temperature is 20-37 °C, and sodium acetate is added to the wastewater.

[0044] The present invention is illustrated below by specific examples. It should be understood that these examples are only used to illustrate the present invention and not to limit the scope of the present invention. Without departing from the spirit and scope of the inventive concept, the changes and advantages that can be conceived by those skilled in the art are included in the present invention, and the scope of protection of the present invention is defined by the appended claims and any equivalents thereof.

[0045] Example 1: Obtaining Microbacterium flavescens B1

[0046] 1.1 Preparation of the culture medium

[0047] Table 1 Formulation of aerobic ZPM14 liquid medium

[0048] Reagent Dosage for 1 L Ammonium sulfate 2.0g Dipotassium hydrogen phosphate 1.0g Magnesium sulfate 0.5g Calcium carbonate 1.0g Sodium chloride 10.0g Purified water Make up to 1.0 L

[0049] According to the formulation in Table 1, weigh the corresponding amounts of reagents into an Erlenmeyer flask, add the corresponding amount of boiled pure water, stir and dissolve with a glass rod, adjust the pH value to 7.0, dispense into glass bottles, and the height of the liquid dispensed does not exceed 2 / 3 of the height of the glass bottle; cover with a stopper and attach a culture medium label paper, and sterilize at 121 °C by high-temperature moist heat for 15 min.

[0050] The aerobic ZPM14 agar medium is based on the aerobic ZPM14 liquid medium, with 15 g of agar added per liter of the medium.

[0051] 1.2 Isolation of Strains

[0052] Sample treatment: In a laminar flow hood, take 5 mL of municipal sewage sludge sample, place it in a 50 mL sterile centrifuge tube, add an equal volume of sterile protective agent, vortex for 2 min, and dispense it into sterile screw-cap tubes, 1 mL per tube.

[0053] Sample coating and isolation: Dilute the treated sample by a factor of 10 in a gradient to 10 -4 , and coat it onto the aerobic ZPM14 agar medium, and culture it at 37 °C for 7 d in an aerobic environment.

[0054] 1.3 Primary screening and re-screening of strains

[0055] Primary screening of strains: Pick single colonies into 96-well plates containing aerobic ZPM14 liquid medium (confirm that the pH value is in the range of 6.5 - 7.0 before use), and culture them at 37 °C for 2 d in an aerobic environment. After the culture is completed, aspirate the cultured bacterial liquid into a new 96-well plate, add an equal volume of Griess reagent (Feijing Bio, PLM053), and observe whether the color turns purple-red. If the color turns purple-red, it is identified as positive, indicating the formation of nitrite, and screen the positive well positions for purification and re-screening.

[0056] Re-screening of strains: According to the results of the primary screening, pick the bacterial liquid corresponding to the positive wells in the 96-well plate, and perform three-zone streaking purification on the aerobic ZPM14 agar medium. After single colonies grow, according to the colony morphology growing on the petri dish, pick single colonies in the third region into 96-well plates containing aerobic ZPM14 liquid medium and culture for 2 d. Then, aspirate the bacterial liquid in the 96-well plate again and inoculate it into a centrifuge tube containing 5 mL of aerobic ZPM14 liquid medium, culture it aerobically at 37 °C for 3 d, add 400 μL of Griess reagent, and observe whether the color turns purple-red. If the color turns purple-red, it is identified as positive, indicating the formation of nitrite, and screen the positive strains, which are the strains with ammonia oxidation ability.

[0057] In the above re-screening process, the positive control is to add 400 μL of Griess reagent to a centrifuge tube containing 5 mL of 6.4×10 -6 mol / L sodium nitrite solution. After adding the Griess reagent, it is observed that the color changes from colorless and transparent to purple-red (see Figure 2 ); the negative control is to add 400 μL of Griess reagent to a centrifuge tube containing 5 mL of aerobic ZPM14 liquid medium. After adding the Griess reagent, it is observed that the color does not turn purple-red and remains colorless and transparent (see Figure 2 ). The color development result of strain B1 of the present invention in the re-screening process is shown in Figure 1, indicating that the strain has ammonia oxidation ability and can convert ammonia nitrogen into nitrite.

[0058] 1.4 Identification of the Strain

[0059] According to the results of the secondary screening, a bacterial solution corresponding to a positive well in the 96-well plate was picked and inoculated into TSB medium (HaiBo Biotech, HB4114), and aerobically cultured for 3 d. 16S rRNA sequencing was performed, and the obtained 16S rRNA sequence is shown as SEQ ID NO:1. After identification, the strain belongs to Aquamicrobium defluvii ). The strain was named Aquamicrobium defluvii B1, and was deposited at the China Center for Type Culture Collection (abbreviated as "CCTCC") on March 31, 2025. The address of the depositary institution is Wuhan University, Wuhan, China, and the deposit number is CCTCC No: M 2025640.

[0060] Example 2: Ammonia Oxidation Ability Test of

[0061] 2.1 Preparation of Seed Liquid

[0062] was inoculated into TSB medium (HaiBo Biotech, HB4114) and aerobically cultured until the logarithmic growth phase to obtain a seed liquid.

[0063] 2.2 Ammonia Oxidation Ability of

[0064] Prepare aerobic ZPM14 liquid medium according to the method of Example 1, with the only difference being: changing the amount of ammonium sulfate used so that the ammonia nitrogen (NH4 + -N) concentrations in the prepared aerobic ZPM14 liquid medium are 5, 30, 60, 100, 200, 2000 mg / L respectively; sodium chloride was not added.

[0065] According to an inoculation amount of 3%, inoculate the seed liquid into the prepared aerobic ZPM14 liquid medium with different ammonia nitrogen concentrations (5, 30, 60, 100, 200, 2000 mg / L respectively), and after culturing at 37°C for 3 d in an aerobic environment, detect the contents of ammonia nitrogen (NH4 + -N), nitrite nitrogen (NO2 - -N) and total nitrogen (TN), and the results are shown in Table 2.

[0066] Table 2 Ammonia Oxidation Ability of the Strain at Different Initial Ammonia Nitrogen Concentrations

[0067] <![CDATA[Initial NH4 + -N (mg / L)]]> <![CDATA[NH4 - N (mg / L) after 3 d]]> + > <![CDATA[NO2 after 3 d - -N (mg / L)]]> TN (mg / L) after 3 d 5.0 0.7 4.3 4.9 30.0 1.6 28.1 29.8 60.0 0.2 59.5 59.9 100.0 1.9 97.3 99.4 200.0 14.8 184.6 199.7 2000.0 98.1 1891.5 1990.0

[0068] As can be seen from Table 2, the sewage microbacterium B1 of the present invention can convert ammonia nitrogen into nitrite nitrogen and can tolerate a relatively high ammonia nitrogen concentration. When the concentration of NH4 + -N is 2000 mg / L, effective conversion of ammonia nitrogen to nitrite nitrogen can still be achieved, and the ammonia nitrogen conversion rate can reach 95% within 3 days.

[0069] 2.3 Ammonia oxidation ability of sewage microbacterium B1 under different salinities

[0070] Prepare the aerobic ZPM14 liquid medium according to the method of Example 1, with the only difference being: change the amount of ammonium sulfate used so that the ammonia nitrogen (NH4 + -N) concentration in the prepared aerobic ZPM14 liquid medium is 2000 mg / L; change the amount of sodium chloride used so that the NaCl content in the prepared aerobic ZPM14 liquid medium is 0, 1, 5, 10, 20, 30 g / L respectively.

[0071] According to an inoculation amount of 3%, inoculate the seed liquid into the prepared aerobic ZPM14 liquid medium with different salinities (NaCl contents are 0, 1, 5, 10, 20, 30 g / L respectively). After culturing at 37°C for 3 d under aerobic conditions, detect the contents of ammonia nitrogen (NH4 + -N), nitrite nitrogen (NO2 - -N) and total nitrogen (TN). The results are shown in Table 3.

[0072] Table 3 Ammonia oxidation ability of strains under different salinities

[0073] Salt concentration (g / L) <![CDATA[NH4 + -N (mg / L)]]> <![CDATA[NO2 - -N (mg / L)]]> TN (mg / L) 0 98.1 1891.5 1990.0 1 355.7 1643.6 1999.6 5 429.8 1568.9 1998.8 10 1605.3 393.4 1998.7 20 1571.2 428.3 1999.5 30 1621.8 377.9 1999.1

[0074] As can be seen from Table 3, the sewage microbacterium B1 of the present invention has a certain salt tolerance and can play an ammonia oxidation role to oxidize ammonia nitrogen to nitrite nitrogen in an environment where the salinity is not higher than 3% (i.e., the sodium chloride concentration is not higher than 30 g / L); when the salinity is not higher than 0.5% (i.e., the sodium chloride concentration is not higher than 5 g / L), the ammonia nitrogen conversion rate of this strain can reach more than 78% within 3 days.

[0075] 2.4 Ammonia oxidation ability of sewage microbacterium B1 under different temperatures

[0076] Prepare the aerobic ZPM14 liquid medium according to the method of Example 1, with the only difference being: change the amount of ammonium sulfate used so that the ammonia nitrogen (NH4 + -N) concentration in the prepared aerobic ZPM14 liquid medium is 2000 mg / L; no sodium chloride is added. According to an inoculation amount of 3%, inoculate the seed liquid into the prepared aerobic ZPM14 liquid medium. After culturing at different temperatures (temperatures are 10°C, 20°C, 37°C, 40°C respectively) for 3 d under aerobic conditions, detect the ammonia nitrogen (NH4+ -N), nitrite nitrogen (NO2 - -N) and total nitrogen (TN) contents, and the results are shown in Table 4.

[0077] Table 4 Ammonia oxidation ability of the strain at different temperatures

[0078] Culture temperature (°C) <![CDATA[NH4 + -N (mg / L)]]> <![CDATA[NO2 - -N (mg / L)]]> TN (mg / L) 10 1807.4 183.2 1991.1 20 266.3 1728.9 1995.0 37 98.1 1891.5 1990.0 40 1611.9 387.8 1999.7

[0079] As can be seen from Table 4: The sewage microbacterium B1 of the present invention has ammonia oxidation ability in the environment of 10~40 °C, and can realize the conversion of ammonia nitrogen → nitrite nitrogen, and the optimum temperature is 20~37 °C.

[0080] 2.4 Ammonia oxidation ability of sewage microbacterium B1 under different pH values

[0081] Prepare the aerobic ZPM14 liquid medium according to the method of Example 1, with the difference only that: the pH values of the prepared aerobic ZPM14 liquid medium are 5, 6, 7, 8, and 9 respectively; change the dosage of ammonium sulfate to make the ammonia nitrogen (NH4 + -N) concentration in the prepared aerobic ZPM14 liquid medium is 2000 mg / L; sodium chloride is not added. According to an inoculation amount of 3%, inoculate the seed liquid into the prepared aerobic ZPM14 liquid medium with different pH values (pH values are 5, 6, 7, 8, and 9 respectively), and culture at 37 °C for 3 d in an aerobic environment, then detect ammonia nitrogen (NH4 + -N), nitrite nitrogen (NO2 - -N) and total nitrogen (TN) contents, and the results are shown in Table 5.

[0082] Table 5 Ammonia oxidation ability of the strain under different pH values

[0083] pH value <![CDATA[NH4 + -N (mg / L)]]> <![CDATA[NO2 - -N (mg / L)]]> TN (mg / L) 5 1812.3 196.5 1998.7 6 1614.7 393.1 2006.2 7 98.1 1891.5 1990.0 8 89.3 1909.8 1999.4 9 327.6 1671.5 1999.2

[0084] As can be seen from Table 5: The sewage microbacterium B1 of the present invention can oxidize ammonia nitrogen to nitrite nitrogen in the environment with a pH value of 5~9. When the environmental pH value is 7~9, the ammonia oxidation efficiency of this strain is relatively high, and the ammonia nitrogen conversion rate can reach more than 83% within 3 days.

[0085] Example 3: Application of sewage microbacterium B1 in biological nitrogen removal of wastewater

[0086] 3.1 Biological nitrogen removal device

[0087] The biological nitrogen removal device is a modified sequencing batch reactor (MSBR) of a domestic sewage treatment plant. The wastewater treatment process is as follows: After the wastewater to be treated is homogenized in the equalization tank, it enters the anaerobic tank and is mixed with the sludge refluxed from the aerobic tank. The phosphorus-rich sludge completes the phosphorus release reaction in the anaerobic tank. The effluent of the anaerobic tank enters the anoxic tank and is mixed with the wastewater refluxed from the aerobic tank for denitrification treatment, converting the nitrate nitrogen in the wastewater into nitrogen gas. The effluent of the anoxic tank enters the aerobic tank for nitrification treatment, converting the ammonia nitrogen in the wastewater into nitrate nitrogen, and then the wastewater is refluxed to the anoxic tank, and the sludge is refluxed to the anaerobic tank.

[0088] The original biological nitrogen removal device adopted the full nitrification and denitrification process. In this embodiment, Microbacterium flavescens B1 is used to optimize and transform it, changing the bacterial species composition in the aerobic tank and transforming the full nitrification and denitrification process into the shortcut nitrification and denitrification process.

[0089] 3.2 Influent water quality

[0090] The influent is domestic sewage generated in a certain area of Zhoushan, and the water quality is as follows: COD 205 mg / L, BOD 100 mg / L, ammonia nitrogen concentration 27 mg / L, total nitrogen concentration 28 mg / L, total phosphorus concentration 1 mg / L, salinity 0.3%.

[0091] 3.3 Bacterial species preparation

[0092] Inoculate Microbacterium flavescens into the TSB medium (HaiBo Biotech, HB4114) and aerobically culture it for 5 d to obtain the bacterial liquid.

[0093] 3.4 Adaptation and elimination stage of bacterial species (7 days)

[0094] Adjust the opening degree of the aeration valve and the aeration air volume of the aerobic tank, and control the dissolved oxygen concentration in the aerobic tank at 1.5 - 2.0 mg / L. Inoculate the bacterial liquid at the influent end of the aerobic tank, adding 10 mL of the bacterial liquid per liter of influent. The influent water temperature of the MSBR device is controlled at 25 - 30 °C, and the pH value in the aerobic tank is controlled at 7.5 - 7.8 by adding liquid caustic soda. The dosage of sodium acetate in the aerobic tank is adjusted according to the nitrate nitrogen concentration detected in the anoxic tank, and the mass ratio of nitrate nitrogen to sodium acetate is 1:20. After the domestic sewage is treated in the aerobic tank, it is refluxed to the anoxic tank for denitrification and nitrogen removal. The hydraulic retention times in the aerobic tank and the anoxic tank are 15 h and 10 h respectively, and the daily influent volume of the MSBR device is 15,000 m 3 , and it operates continuously for 7 days. During this period, the changes in the ammonia nitrogen removal rate, total nitrogen removal rate, and nitrite accumulation rate of the MSBR device are as Figure 3 shown. In this stage, the ammonia nitrogen and total nitrogen removal rates are < 60%, and the ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) are in the active adjustment and elimination stage, and nitrification is still mainly the full nitrification process.

[0095] 3.5 Rapid Bacterial Growth Period (10 days)

[0096] After the adaptation and elimination of the bacteria, adjust the opening degree of the aeration valve and the aeration volume of the aerobic tank, and control the dissolved oxygen concentration in the aerobic tank at 0.5 - 1.2 mg / L. Continue to inoculate the bacterial solution at the inlet end of the aerobic tank, adding 10 mL of the bacterial solution per liter of domestic sewage. Control the inlet water temperature of the MSBR device at 25 - 30 °C, and control the pH value in the aerobic tank at 7.5 - 7.8 by adding liquid caustic soda. The dosage of sodium acetate in the aerobic tank is adjusted according to the nitrate nitrogen concentration detected in the anoxic tank, and the mass ratio of nitrate nitrogen to sodium acetate is 1:20. After the domestic sewage is treated in the aerobic tank, it flows back to the anoxic tank for denitrification. The hydraulic retention times in the aerobic tank and the anoxic tank are 15 h and 10 h respectively, and the daily influent volume of the MSBR device is 15,000 m 3 , and continuously operate for 10 days. During this period, the changes in the ammonia nitrogen removal rate, total nitrogen removal rate, and nitrite accumulation rate of the MSBR device are as Figure 3 shown. During this stage, the nitrite concentration in the aerobic tank continuously increases, the nitrate concentration gradually decreases, the ammonia nitrogen removal rate shows an upward trend over time, the reproduction rate of AOB is higher than that of NOB, and AOB gradually becomes the dominant strain.

[0097] 3.6 Stable Period (10 days)

[0098] Adjust the opening degree of the aeration valve and the aeration volume of the aerobic tank, and control the dissolved oxygen concentration in the aerobic tank at 0.4 - 0.5 mg / L. Control the inlet water temperature of the MSBR device at 25 - 30 °C, and control the pH value in the aerobic tank at 7.5 - 7.8 by adding liquid caustic soda. The dosage of sodium acetate in the aerobic tank is adjusted according to the nitrate nitrogen concentration detected in the anoxic tank, and the mass ratio of nitrate nitrogen to sodium acetate is 1:20. After the domestic sewage is treated in the aerobic tank, it flows back to the anoxic tank for denitrification. The hydraulic retention times in the aerobic tank and the anoxic tank are 15 h and 10 h respectively, and the daily influent volume of the MSBR device is 15,000 m 3 , and continuously operate for 10 days. During this period, the changes in the ammonia nitrogen removal rate, total nitrogen removal rate, and nitrite accumulation rate of the MSBR device are as Figure 3 shown. During this stage, the concentrations of ammonia nitrogen, nitrate, and nitrite in the aerobic tank are stable, the effluent ammonia nitrogen is stably lower than 0.5 mg / L, the ammonia nitrogen removal rate exceeds 95%, the cumulative rate of nitrite reaches 90% and is in a stable state, indicating that the establishment of shortcut nitrification and denitrification is completed.

[0099] Unless otherwise defined, all technical and scientific terms used in this invention have the same meanings as commonly understood by those of ordinary skill in the art to which this disclosure belongs. The raw materials and equipment used in this invention are conventional raw materials and equipment in the art and can be obtained from conventional commercial channels unless otherwise specified; the methods used in this invention are conventional methods in the art unless otherwise specified.

[0100] As described above, the above are only the preferred embodiments of the present invention and do not impose any limitations on the present invention. Any simple modifications, changes, and equivalent transformations made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A Microbacterium sp. with ammonia oxidation ability ( Aquamicrobium defluvii ), characterized in that The strain name of the Aquamicrobium defluvii is B1, and the preservation number is CCTCC No: M 2025640.

2. A microbial inoculum with ammonia oxidation ability, characterized in that, The microbial agent includes the Aquamicrobium defluvii according to claim 1.

3. The microbial inoculant according to claim 2, wherein The microbial agent is a bacterial liquid or bacterial powder.

4. A preparation method of the microbial inoculum according to claim 2 or 3, characterized in that, It includes the following steps: Pick the Aquamicrobium defluvii and inoculate it into a tryptic soy broth liquid medium, and perform aerobic culture at 35-37 °C for 3-6 days.

5. Use of the microorganism Hydrogenophaga palleronii according to claim 1 or the microbial agent according to claim 2 or 3 in an ammonia oxidation reaction, characterized in that, The ammonia oxidation reaction is: under the action of the Aquamicrobium defluvii or the microbial agent, ammonia nitrogen is converted into nitrite.

6. The application according to claim 5, characterized in that, The conditions of the ammonia oxidation reaction are as follows: the initial ammonia nitrogen concentration is 5-2000 mg / L, the salinity is not higher than 3%, the temperature is 10-40 °C, and the pH value is 5-9.

7. Use of the Microbacterium flavescens according to claim 1 or the microbial inoculum according to claim 2 or 3 in wastewater treatment, characterized in that, It includes the following steps: Use the Aquamicrobium defluvii or the microbial agent to perform shortcut nitrification treatment on the wastewater. After converting the ammonia nitrogen in the wastewater into nitrite nitrogen, use denitrifying bacteria to convert the nitrite nitrogen into nitrogen.

8. The application according to claim 7, characterized in that, During the shortcut nitrification treatment, control the dissolved oxygen concentration of the wastewater to be 0.4-0.5 mg / L, the pH value to be 7-9, and the temperature to be 20-37 °C.

9. The application according to claim 7 or 8, characterized in that, During the shortcut nitrification treatment, add sodium acetate to the wastewater.

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