Method for cooperatively treating erucyl amide wastewater by arthrobacter and bacillus megatherium based on staged aeration regulation

Abstract

The invention discloses a method for cooperatively treating erucyl amide wastewater by arthrobacter and bacillus megatherium based on staged aeration regulation and control, and belongs to the technical field of environmental microorganisms. According to the method, pre-cultured arthrobacter and bacillus megatherium are prepared into a complex microbial inoculant, the complex microbial inoculant is inoculated into erucyl amide wastewater, and biological enhancement treatment is carried out by adopting a staged aeration regulation and control strategy: in a stage I, a high aeration condition is adopted to activate thalli to rapidly proliferate and induce amidase expression; and in the stage II, the low aeration condition is adjusted to optimize the anoxic environment of the deamidation reaction. The space-time synergistic effect of the two functional bacteria is achieved by regulating and controlling the dissolved oxygen concentration, that is, the bacillus megatherium preferentially degrades ammonia nitrogen pollutants, the arthrobacter specifically catalyzes amido bonds of erucyl amide to split, and metabolic pathways of the bacillus megatherium and the arthrobacter form complementation; the process conforms to the green chemistry principle, no secondary pollutants are generated, and a new efficient and sustainable biological treatment way is provided for the erucyl amide-containing refractory organic wastewater.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental microorganisms, and in particular relates to a method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration regulation. Background Art

[0002] In contemporary industrial production, erucamide, as a key fine chemical raw material, is widely used in the plastics, ink and coating industries. In the plastics industry, it acts as a lubricant and anti-sticking agent, significantly improving the quality and processing performance of plastic products; in the ink industry, it enhances the fluidity and dispersibility of inks, ensuring the quality of printed products; in the coating field, it enhances the wear resistance and scratch resistance of coatings, and is used in high-end coating products. However, the expansion of erucamide production has led to increasingly serious wastewater pollution problems.

[0003] The composition of erucamide wastewater is complex, containing high concentrations of long-chain fatty acids, amide substances and additives, and is difficult to degrade naturally. Direct discharge will lead to eutrophication of water bodies, destroy the ecological balance, and affect aquatic life; at the same time, it will destroy the physical and chemical properties of the soil, affect soil fertility and microbial communities, and threaten the stability of the ecosystem. Traditional physical treatment methods such as sedimentation and filtration can remove suspended particles and impurities, but have limited effects on the removal of dissolved organic matter and nutrients, and have high energy consumption. Chemical treatment methods such as chemical oxidation and coagulation sedimentation can decompose and remove pollutants, but require a large amount of chemical reagents, are costly and easily cause secondary pollution.

[0004] Biological treatment methods have attracted much attention due to their low cost and environmental friendliness. However, traditional biological treatment methods, such as the activated sludge method, have the following defects in treating erucamide wastewater:

[0005] 1. Traditional biological methods are inefficient: For example, the Chinese patent CN105198112A (publication date: 2015.12.30) is not efficient enough in degrading long-chain fatty acids and amides in erucamide wastewater, and high concentrations of pollutants and special chemical compositions may inhibit microbial growth and metabolism, resulting in poor treatment effects. The activated sludge method has a COD (chemical oxygen demand) removal rate of less than 65%, and ammonia nitrogen removal rate of less than 55%;

[0006] 2. Poor tolerance to high salt: When the salinity of wastewater is greater than 2% NaCl, the activity of microorganisms is inhibited and the COD removal rate drops to less than 50%;

[0007] 3. The treatment cycle is as long as 72-96 hours, the equipment occupies a large area, and the construction cost is increased. It has weak adaptability to water quality and water volume shocks and is difficult to cope with fluctuations. Moreover, it is easy to produce a large amount of residual sludge, which is difficult to dispose of later and the cost is quite high.

[0008] In addition, with increasingly stringent environmental protection requirements and the continuous improvement of wastewater discharge standards, conventional biological treatment methods can no longer meet discharge requirements.

[0009] Therefore, it is urgent to develop an efficient, low-cost and environmentally friendly method for treating erucamide wastewater. This is not only an urgent need to solve current environmental problems, but also the key to promoting the sustainable development of related industries, and has important practical significance for achieving the coordinated development of economy and environment. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide a method for the coordinated treatment of erucamide wastewater by Arthrobacter and Bacillus megaterium based on staged aeration regulation, which significantly improves the treatment efficiency of erucamide wastewater, reduces the treatment cost, ensures that the wastewater can stably meet the emission standards, and realizes the coordinated development of environmental protection and economic benefits.

[0011] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0012] A method for treating erucamide wastewater by synergistically using Arthrobacter and Bacillus megaterium based on staged aeration regulation comprises the following steps:

[0013] 1) Bacterial culture: Cultivate Arthrobacter species and Bacillus megaterium species;

[0014] 2) Compounding and inoculation of bacterial agents: Compounding and inoculating the Arthrobacter and Bacillus megaterium strains cultured in step 1) into the erucamide wastewater;

[0015] 3) Phased bioaugmentation treatment;

[0016] 4) Subsequent treatment: After the bioaugmentation treatment, solid-liquid separation is carried out, and the supernatant is adsorbed by activated carbon and filtered by membrane.

[0017] In the step 1), the culture process of the Arthrobacter species is as follows: using LB medium, adding 0.1 wt% erucic acid amide to induce enzyme activity, and shaking and culturing at 30°C and 150 rpm until the OD 600 is 2.0.

[0018] In the step 1), the Bacillus megaterium strain culture process is: using an optimized fermentation medium, 37° C., 200 rpm shaking culture for 18 h until the spore formation rate is ≥90%.

[0019] The LB medium was prepared by mixing 10 g / L tryptone, 5 g / L yeast extract, 10 g / L NaCl, pH 7.0, and sterilizing at 121°C for 20 min.

[0020] The preparation of the optimized fermentation medium includes: 20 g / L glucose and 1 g / L potassium dihydrogen phosphate, pH 7.0, and sterilization conditions of 121°C for 20 min.

[0021] In the step 2), the volume ratio of Arthrobacter and Bacillus megaterium is 3-1:1-3.

[0022] In the step 2), the volume of the erucamide wastewater is 10-100 L.

[0023] In the step 2), the COD concentration of the erucamide wastewater is 1000-3000 mg / L.

[0024] In step 3), the process of bio-augmented wastewater treatment in stages is: two-stage reaction: stage I: aeration volume 2.5 L / min, dissolved oxygen DO maintained at 5.0-6.0 mg / L; stage II: aeration reduced to 1.0 L / min, dissolved oxygen DO controlled at 1.5-2.0 mg / L.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] (1) The present invention utilizes the ammonia nitrogen degradation ability of Bacillus megaterium (ammonia nitrogen removal rate ≥ 94.7%) and the erucamide-specific degradation function of Arthrobacter, activates the rapid proliferation of bacteria and induces amidase through high aeration in stage I, and optimizes the anoxic deamidation reaction conditions through low aeration in stage II, thereby achieving synergistic metabolism.

[0027] (2) The present invention adopts staged aeration control: in stage I (0-12 h), the aeration volume is 2.5 L / min, and the COD is degraded by 40%-50%. In stage II (12-48 h), the aeration volume is 1.0 L / min, the erucamide degradation rate is increased to ≥85%, the COD removal rate is ≥80%, and the simultaneous degradation rate of ammonia nitrogen is ≥75%. It is suitable for high-salt (≤5% NaCl) wastewater, and effectively ensures that the wastewater is stably discharged in compliance with the standards.

[0028] (3) The treatment method of the present invention is low-cost, and the bacterial agent can be reused 3-5 times. When the volume ratio of Arthrobacter to Bacillus megaterium seed liquid is 3:1, the COD removal rate is the highest (88.4%), and the bacterial agent can be reused 5 times, reducing the cost by 40%. The entire treatment process is green and environmentally friendly, does not generate secondary pollution, has significant economic and environmental benefits, and provides a sustainable and innovative solution for the treatment of erucamide wastewater. DETAILED DESCRIPTION

[0029] The present invention is further illustrated below in conjunction with specific examples. The examples are implemented based on the technical solutions of the present invention. It should be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0030] The COD in the following examples was tested using the potassium dichromate method (HJ828-2017).

[0031] In the following examples, Arthrobacter sp. (CGMCC NO: 23463) is described in the Chinese invention patent with publication number CN114437979A: Arthrobacter capable of degrading erucamide, its acquisition method, culture method and application; Bacillus megaterium (CTCCC NO: M2012381) is described in the Chinese invention patent with publication number CN110194722A: A method for separating and extracting erucamide using Bacillus megaterium.

[0032] Example 1

[0033] Preparation of compound bacterial agent

[0034] (1) Bacterial culture

[0035] Arthrobacter sp. (CGMCC NO: 23463): LB liquid medium (tryptone 10 g / L, yeast extract 5 g / L, NaCl 10 g / L, pH 7.0, sterilization conditions: 121 °C, 20 min), 0.1% (w / w) erucamide was added as an enzyme activity inducer, and cultured at 30 °C, 150 rpm with shaking until OD 600 2.0 (about 24 h, at which time the bacterial concentration is ≥ 1×10 8 CFU / mL).

[0036] Bacillus megaterium (CCTCC NO: M2012381): Use optimized fermentation medium (glucose 20 g / L, potassium dihydrogen phosphate 1 g / L, pH 7.0, sterilization conditions are 121 ℃, 20 min), culture at 37 ℃, 200 rpm for 18 h, spore formation rate ≥ 90% (refer to the improved malachite green staining method in "GB / T 4789.2-2016 Food Microbiology Test Total Colony Count Determination").

[0037] (2) Mix the Arthrobacter and Bacillus megaterium seed liquids in a volume ratio of 3:1 to obtain a composite bacterial agent. The activity of the bacterial agent was measured by measuring the OD 600 And the 24 h degradation rate (≥50%) of the simulated wastewater (COD 1000 mg / L) was verified.

[0038] Example 2

[0039] (1) Phased intensive treatment

[0040] Wastewater parameters: wastewater volume was 50 L, initial COD concentration was 1500 mg / L, ammonia nitrogen concentration was 120 mg / L, salinity was 2% NaCl, and pH was 8.3.

[0041] Inoculation: The composite bacterial agent prepared in Example 1 was inoculated into the erucamide wastewater at an inoculation rate of 5% of the wastewater volume (i.e., 2.5 L of bacterial agent was inoculated into 50 L of wastewater); the pH was adjusted to 7.0±0.2 (using NaOH / HCl for adjustment), and soluble starch (food grade) was added as a co-metabolic carbon source (C / N=15:1).

[0042] Staged enhanced treatment: Stage I (0-12 h): control aeration volume to 2.5 L / min, maintain dissolved oxygen (DO) at 5.0-6.0 mg / L, temperature at 30±1 ℃, COD degradation rate at 48.7%, erucamide degradation rate at 26.7% (HPLC method, GB / T 32952-2016), ammonia nitrogen removal rate at 74.7% (Nessler reagent method); Stage II (12-48 h): reduce aeration volume to 1.0 L / min, control DO at 1.5-2.0 mg / L, temperature at 30±1 ℃, COD degradation rate at 88.4%, erucamide degradation rate at 86.7%, ammonia nitrogen simultaneous removal rate at 90.2%. The effluent effect results are shown in Table 1.

[0043] (2) Subsequent processing

[0044] Solid-liquid separation: After the bioaugmentation treatment, the wastewater was separated into solid and liquid by centrifugation technology. The centrifugation was performed at 4000 rpm for 10 min, and the bacterial recovery rate was ≥95% (wet weight method).

[0045] Advanced treatment: The separated supernatant is further treated with activated carbon adsorption (particle size 200 mesh, dosage 2 g / L) and high-precision membrane filtration (0.22 μm PVDF) to ensure that residual organic matter, pigments, tiny particles and soluble pollutants in the wastewater are effectively removed.

[0046] Table 1 Water output effect

[0047]

[0048] The results in Table 1 show that the following conclusions can be drawn:

[0049] (1) The synergistic effect of staged aeration is obvious

[0050] In this example, the metabolic functions of the two bacterial communities are complemented by regulating the oxygen gradient in phase I (aerobic phase, DO 5.0-6.0 mg / L) and phase II (microaerobic phase, DO 1.5-2.0 mg / L):

[0051] Phase I: The high dissolved oxygen environment significantly activated the amidase activity of Arthrobacter, with a COD degradation rate of 48.7% (0-12 h) and an erucamide degradation rate of 26.7%, laying the foundation for the subsequent deamidation reaction.

[0052] Phase II: After reducing the aeration volume, the ammonia oxidation function of Bacillus megaterium became dominant, and the ammonia nitrogen degradation rate jumped from 74.7% in phase I to a total degradation rate of 90.2%. At the same time, the erucamide degradation rate increased to 86.7%, reflecting the sequential switching of bacterial functions driven by the oxygen environment.

[0053] (2) Pollutant removal efficiency meets all standards

[0054] COD: dropped from 1500 mg / L to 68.5 mg / L, which is better than the first-level standard of "Comprehensive Sewage Discharge Standard" (GB 8978-2002) (COD≤100 mg / L).

[0055] Ammonia nitrogen: The concentration after deep treatment is 0.96 mg / L, meeting the most stringent "Surface Water Environmental Quality Standard" (GB3838-2002) Class III water body requirements (ammonia nitrogen ≤1.0 mg / L).

[0056] Erucamide: The final concentration was below the detection limit (0.5 mg / L), achieving complete harmlessness.

[0057] (3) Outstanding technical and economic advantages

[0058] Treatment cycle optimization: The total treatment time is 48 hours (including deep treatment), which is 33%-50% more efficient than the traditional activated sludge method (72-96 hours), and no additional chemical agents are required, with no risk of secondary pollution.

[0059] (4) Verification of innovative technical features

[0060] Necessity of oxygen gradient regulation: Comparative experiments show (see Comparative Example 1) that the COD removal rate of constant DO treatment (5.0 or 1.5 mg / L) is only 68.3%-79.5%, which is significantly lower than the 88.4% of staged aeration, proving the irreplaceable role of dynamic regulation of oxygen environment for bacterial synergy.

[0061] Process adaptability: This solution still maintains high-efficiency treatment capabilities for wastewater with high salt content (2% NaCl) and complex pollutants (COD / ammonia nitrogen / amide coexistence), breaking through the environmental tolerance bottleneck of traditional biological methods.

[0062] Example 3

[0063] The difference between this embodiment and embodiment 2 is that:

[0064] Wastewater parameters: The volumes of the three groups of erucamide wastewater were 10 L, 50 L, and 100 L, respectively; the initial COD concentration was 1500±50 mg / L, the ammonia nitrogen concentration was 100±5 mg / L, the salinity was 2% NaCl, and the pH was 8.5±0.3.

[0065] The COD degradation rate in stage I was 45%-48%; the degradation rate of erucamide in stage II was ≥85% (HPLC method, GB / T32952-2016), and the ammonia nitrogen removal rate was ≥80% (Nessler's reagent method, HJ535-2009). The effluent effect results are shown in Table 2.

[0066] Table 2 Water output effect

[0067]

[0068] The results in Table 2 show that within the specification range of 10-100 L, the removal rate of chemical oxygen demand (COD) is ≥83.6%, which is more than 20% higher than that of the traditional activated sludge method. The removal rate of ammonia nitrogen is ≥80.5%, and the energy consumption per unit of wastewater is significantly reduced from 1.8kW·h / m 3 Reduced to 1.3 kW·h / m 3 , a decrease of 27.8%. In addition, the recovery rate of the inoculant remained above 90%. These data fully demonstrate that this method has shown good treatment effects at different scales. It has strong scale adaptability, and the treatment process has good economy and stability, and has the potential for large-scale application.

[0069] Example 4

[0070] The difference between this embodiment and embodiment 2 is that:

[0071] Wastewater parameters: The COD concentrations of the three groups of erucamide wastewater are different. The main parameter indicators of the wastewater are shown in Table 3 below.

[0072] Table 3 Main parameters of wastewater

[0073]

[0074] The COD degradation rate in stage I was 42%-48%. The degradation efficiencies of erucamide and ammonia nitrogen are shown in Table 4. The wastewater COD treatment effect results are shown in Table 5.

[0075] Table 4 Degradation efficiency of erucamide and ammonia nitrogen

[0076]

[0077] Table 5 Wastewater COD treatment effect

[0078]

[0079] The results in Tables 4 and 5 show that the following conclusions can be drawn:

[0080] (1) Significant improvement in processing efficiency

[0081] Degradation efficiency: In a complex wastewater system with COD 1000-3000 mg / L and salinity ≤3% NaCl, the erucamide degradation rate is ≥85.6%, the COD removal rate is ≥84.5%, and the simultaneous removal rate of ammonia and nitrogen is ≥80.3%, which is 20%-40% higher than the traditional activated sludge method (COD removal rate 65%, ammonia and nitrogen removal rate 55%).

[0082] Cycle optimization: The processing cycle is shortened to 48-60 hours (traditional methods require more than 72 hours), and the efficiency is increased by 20%-40%.

[0083] Salt tolerance breakthrough: Under high salt conditions of 3% NaCl, the activity of the bacterial community is not significantly inhibited, breaking through the normal salinity tolerance range of traditional biological methods (usually <2% NaCl).

[0084] (2) Economic advantages

[0085] The phased aeration strategy reduces energy consumption to 1.3-1.8 kW·h / ton, which is 40%-56% energy-saving compared with conventional bioreactors (2.5-3.0 kW·h / ton).

[0086] (3) Environmental benefits

[0087] Green process: No chemical agents are required in the whole process, which avoids the generation of chemical sludge and the risk of secondary pollution. At the same time, compared with chemical treatment methods, this process achieves significant carbon emission reduction.

[0088] (4) Technological innovation

[0089] Synergistic mechanism of bacterial species: Driven by staged aeration, the amidase activity of Arthrobacter (CGMCC 23463) and the fatty acid degradation function of Bacillus megaterium (CCTCC M2012381) formed metabolic complementarity, and the synergistic efficiency was improved by 30%-50%.

[0090] Process adaptability: By dynamically adjusting the aeration volume (from 2.5 L / min to 1.0 L / min) and dissolved oxygen concentration (from 5.0 mg / L to 1.5 mg / L), orderly and efficient degradation of carbon and nitrogen pollutants can be achieved, effectively improving the problem of biological inhibition in a high-salt environment.

[0091] Example 5

[0092] The difference between this embodiment and embodiment 2 is that:

[0093] Wastewater parameters: The volume of the three groups of erucamide wastewater was 50 L, the COD concentration was 2000±30 mg / L, the ammonia nitrogen concentration was 105±5 mg / L, the salinity was 3% NaCl, and the pH was 8.4±0.2.

[0094] Inoculation: The composite bacterial agent obtained by mixing the Arthrobacter and Bacillus megaterium seed solutions of Example 1 in a volume ratio of 3:1, 1:1, and 1:3 was inoculated into the erucamide wastewater.

[0095] The degradation efficiency of erucamide and ammonia nitrogen is shown in Table 6, and the wastewater COD treatment effect results are shown in Table 7.

[0096] Table 6 Degradation efficiency of erucamide and ammonia nitrogen

[0097]

[0098] Table 7 Wastewater COD treatment effect

[0099]

[0100] The results in Tables 6 and 7 show that the composite bacterial community showed good treatment effects at three different ratios, indicating that the method is feasible within a certain bacterial species ratio. Among them, the COD removal rate was the highest at a composite ratio of 3:1, which was 26.9% higher than that of a single bacterial species, fully reflecting the good synergistic effect between the two bacterial species.

[0101] Example 6

[0102] The difference between this embodiment and embodiment 2 is that:

[0103] Wastewater parameters: The water quality characteristics of actual chemical wastewater after traditional anaerobic-aerobic-physical and chemical treatment are: volume 10 L, erucamide concentration 21.7 mg / L, COD concentration 158 mg / L, ammonia nitrogen concentration 16.4 mg / L, pH 8.2, and salinity 3%.

[0104] Inoculation: Adjust the wastewater pH to 7.5 ± 0.2.

[0105] The degradation efficiency of erucamide and ammonia nitrogen is shown in Table 8, the wastewater COD treatment effect results are shown in Table 9, and the changes in the degradation enzyme system are shown in Table 10.

[0106] Table 8 Degradation efficiency of erucamide and ammonia nitrogen

[0107]

[0108] Table 9 Wastewater COD treatment effect

[0109]

[0110] Table 10 Changes in degradation enzyme system

[0111]

[0112] The results in Tables 8 and 9 show that for chemical wastewater containing multiple pollutants (COD / ammonia nitrogen / amide), after traditional biological treatment, the COD removal rate is still as high as 60.5%, indicating that the technology is well adapted to complex wastewater, does not produce chemical sludge, and can achieve carbon emission reduction.

[0113] The results in Table 10 show that the introduction of Bacillus and Bacillus megaterium greatly improves the abundance of microbial degradation enzymes, which is beneficial to the removal of erucamide and difficult-to-degrade substances. Among them, peroxidase helps to maintain a redox environment that is conducive to the degradation of pollutants, accelerates the transformation of organic matter and the removal of pollutants such as nitrogen, indicating that the degradation of organic pollutants by the activated sludge of the invention group can be more efficient. Hydrogenase is involved in a variety of metabolic pathways, including organic matter transformation and energy generation. Its high abundance indicates that microorganisms can more efficiently utilize substrates for energy metabolism and material transformation. The 3.1 and 3.5 series of enzymes show that the invention group has a stronger ability to decompose complex organic molecular structures (such as esters, proteins and nucleic acids), which helps to quickly degrade difficult-to-treat organic pollutants in sewage. The 4.1 and 4.2 series of enzymes indicate that bioaugmentation treatment accelerates the mineralization process of organic matter and enhances the degradation ability of organic pollutants.

[0114] Comparative Example 1

[0115] The difference between this embodiment and embodiment 2 is that:

[0116] Wastewater parameters: The main wastewater parameter indicators are shown in Table 11 below.

[0117] Table 11 Main parameters of wastewater

[0118]

[0119] Inoculation: Inoculate the seed solutions of Arthrobacter and Bacillus megaterium into the erucamide wastewater at an inoculation rate of 5% of the wastewater volume, and adjust the pH to 7.0±0.2.

[0120] Phased enhanced treatment: The control group uniformly adopted an aeration rate of 2.5 L / min throughout the whole process. The treatment time was 72-96 h for the control group and 48 h for the group of the present invention. The bio-enhanced treatment parameters are shown in Table 12.

[0121] Table 12 Bioaugmentation treatment parameters

[0122]

[0123] The treatment effect results of Comparative Example 1 are shown in Table 13.

[0124] Table 13 Treatment effect of comparative example 1

[0125]

[0126] The results in Table 13 show that compared with the single strain treatment, the composite bacterial agent has the following advantages: COD removal rate increased by 8.9%-20.1%, and erucamide degradation rate increased by 28.1%-64.3%; compared with the traditional activated sludge method, the composite bacterial agent has the following advantages: treatment cycle shortened by 50%, COD removal rate increased by 23.4%, and erucamide degradation rate increased by 63.1%, showing a significant synergistic effect.

[0127] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration regulation, characterized in that: The following steps are involved: 1) Bacterial culture: Cultivate Arthrobacter species and Bacillus megaterium species; 2) Compounding and inoculation of bacterial agents: Compounding and inoculating the Arthrobacter and Bacillus megaterium strains cultured in step 1) into the erucamide wastewater; 3) Phased bioaugmentation treatment; 4) Subsequent treatment: After the bioaugmentation treatment, solid-liquid separation is carried out, and the supernatant is adsorbed by activated carbon and filtered by membrane.

2. The method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration control according to claim 1, characterized in that: In the step 1), the culture process of the Arthrobacter species is as follows: using LB medium, adding 0.1 wt% erucic acid amide to induce enzyme activity, and shaking and culturing at 30°C and 150 rpm until the OD 600 is 2.

0.

3. The method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration control according to claim 1, characterized in that: In the step 1), the culture process of Bacillus megaterium is: using optimized fermentation medium, shaking culture at 37°C and 200 rpm for 18 hours until the spore formation rate is ≥90%.

4. The method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration control according to claim 2, characterized in that: The LB medium was prepared by mixing 10 g / L tryptone, 5 g / L yeast extract, 10 g / L NaCl, pH 7.0, and sterilizing at 121°C for 20 min.

5. The method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration control according to claim 3, characterized in that: The preparation of the optimized fermentation medium includes: 20 g / L glucose and 1 g / L potassium dihydrogen phosphate, pH 7.0, and sterilization conditions of 121°C for 20 min.

6. The method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration control according to claim 1, characterized in that: In the step 2), the volume ratio of Arthrobacter and Bacillus megaterium is 3-1:1-3.

7. The method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration control according to claim 1, characterized in that: In the step 2), the volume of the erucamide wastewater is 10-100 L.

8. The method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration control according to claim 1, characterized in that: In the step 2), the COD concentration of the erucamide wastewater is 1000-3000 mg / L.

9. The method for treating erucamide wastewater by cooperating with Arthrobacter and Bacillus megaterium based on staged aeration control according to claim 1, characterized in that: In step 3), the process of bio-augmented wastewater treatment in stages is: two-stage reaction: stage I: aeration volume 2.5 L / min, dissolved oxygen DO maintained at 5.0-6.0 mg / L; stage II: aeration reduced to 1.0 L / min, dissolved oxygen DO controlled at 1.5-2.0 mg / L.

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