Geobacillus sp. DC-3 and application thereof

Abstract

The invention relates to a geobacillus sp. DC-3 and an application thereof. The preservation number of the geobacillus sp. DC-3 is CGMCC (China General Microbiological Culture Collection Center) No.28134, and the preservation number of the geobacillus sp. DC-3 is CGMCC No.28134. The geobacillus sp. DC-3 has the following beneficial effects: 1, the geobacillus sp. DC-3 provided by the invention has relatively good degradation capability on crude oil in oilfield produced water, and can degrade the crude oil into metabolites such as carbon dioxide and water; and 2, when the device is applied, sewage treatment equipment does not need to be modified, the dosing port originally arranged on the water inlet pipeline of the water station is directly utilized, the adaptability is good, and the use cost is low. And 3, experimental results show that the geobacillus DC-3 can degrade the crude oil content in the oilfield produced water treated by the geobacillus DC-3 at the temperature of 40 DEG C by more than 87%, so that the water quality is greatly improved.

Description

Technical Field

[0001] The present invention belongs to the technical fields of oilfield sewage treatment and environmental biotechnology, and particularly relates to a Geobacillus sp. DC-3 and its application. Background Art

[0002] Petroleum is a complex mixture composed of various hydrocarbons, containing a small amount of chemical elements such as sulfur, nitrogen, oxygen and trace metals. The hydrocarbon compounds in petroleum include hydrocarbons from methane to those with a relative molecular mass of 1500-2000, mainly including alkanes, cycloalkanes and aromatic hydrocarbons, accounting for about 50%-80% of the petroleum content. Among them, alkanes are the main components of petroleum, with the number of carbon atoms ranging from 1 to 40, and those with 6-8 carbon atoms have a relatively high content in petroleum.

[0003] At present, most oilfields have entered the middle and late stages of development, and the water content in the produced fluid is 60-80%, and in some oilfields it is even as high as 90%. If this oily sewage is directly discharged without treatment, it will cause environmental pollution and a great waste of water resources. Therefore, the oilfield produced water must be treated and reused. Since the requirements for the oil content index in reinjection are very strict, the oil removal technology in the oily sewage treatment process of oilfields has become the key and difficulty of the whole process. For example, Chinese Patent Application No. 102153221A discloses an oilfield produced water treatment process, which involves an adjusting water tank, a flotation device, a pipe mixer, a nitrogen-powered reactor, a sedimentation tank and an ultrasonic filter. Its characteristics are: the oilfield produced water treatment process includes: in step 1, a coagulant is added to the adjusting water tank for the produced water from the oilfield for adjusting and mixing; in step 2, the produced water from the oilfield adjusted in the adjusting water tank in step 1 is introduced into the flotation device together with a flotation agent, a flocculant and a coagulant aid for the first-stage oil removal treatment; in step 2, the produced water from the oilfield after "flotation" treatment is introduced into the pipe mixer; in step 4, nitrogen is used as the gas source and introduced into the nitrogen-powered reactor together with the produced water from the oilfield in the pipe mixer for the second-stage treatment of oil removal and suspended solid removal by flotation; in step 5, the produced water from the oilfield after oil removal and suspended solid removal by flotation is introduced into the sedimentation tank for corrosion inhibition and scale inhibition treatment; in step 6, the produced water from the oilfield after sedimentation treatment is introduced into the ultrasonic filter for the third treatment by ultrasonic vibrators; in step 7, the produced water from the oilfield after ultrasonic filtration is introduced into the purified water tank for sterilization treatment; in step 8, the treated mixture in the purified water tank is introduced into the reinjection system.

[0004] The existing forms of petroleum in petroleum sewage are divided into 4 types: floating oil, dispersed oil, emulsified oil and dissolved oil. Among them, floating oil and dispersed oil can be separated from the oily sewage by standing for a period of time, while emulsified oil and dissolved oil can be stably dispersed in the petroleum sewage and are difficult to remove by general methods.

[0005] Therefore, domestication and screening of microorganisms that can efficiently degrade petroleum substances to treat oily sewage have the advantages of wide distribution, fast reproduction of microorganisms, and can completely degrade pollutants without producing secondary pollution. It is regarded as an oily sewage treatment technology with broad application prospects. For example, Chinese Patent Application CN 107619801A discloses a thermotolerant Pseudoalteromonas and its application and a method for treating oilfield sewage using the same. The strain is named Pseudoalteromonas sp. BJQ-112, which was deposited in the "General Microbiological Center of the China Committee for Culture Collection of Microorganisms" on July 12, 2017, with the deposit number: CGMCC No. 14412. The treatment of oilfield sewage includes the following steps: First, pre-treat the oilfield sewage at a temperature higher than 50°C and lower than 65°C to remove suspended solids and oil. Then, the pre-treated sewage enters the biochemical pool for biochemical treatment. In the biochemical pool, Pseudoalteromonas sp. BJQ-112 is introduced to remove emulsified oil and dissolved oil. Then, it enters the tubular membrane filtration system through a lift pump to remove suspended solids, and finally the water is discharged.

[0006] However, the environmental conditions of oilfield sewage are complex and the requirements for bacterial strains are very high. Currently, the properties of the screened petroleum-degrading bacteria vary greatly, and it is difficult to simultaneously have excellent petroleum-degrading performance and good adaptability to the sewage environment. Therefore, the application scope in oil fields is greatly restricted. Therefore, how to screen out microbial strains that can adapt to the oilfield sewage environment and can effectively degrade crude oil is an urgent problem to be solved in the current application of microbial technology in oily sewage treatment to remove crude oil in sewage. Summary of the Invention

[0007] Object of the Invention: Aiming at the above deficiencies of the prior art, one object of the present invention is to provide a Geobacillus sp. DC-3, which can be applied to the treatment of oilfield sewage.

[0008] Another object of the present invention is to provide a bacterial agent containing the above Geobacillus sp. DC-3 or a fermentation broth prepared from the microbial strain;

[0009] Another object of the present invention is to apply the Geobacillus sp. DC-3, its bacterial agent or fermentation broth to the treatment of oilfield sewage to remove crude oil in the sewage and improve the water quality of the sewage.

[0010] Technical Solution: A Geobacillus sp. DC-3, with the deposit number CGMCC No. 28134.

[0011] The detailed deposit information of a Geobacillus sp. DC-3 is as follows:

[0012] The microbial deposit number is: CGMCC No. 28134

[0013] The deposit date is: August 9, 2023

[0014] Its taxonomic name is: Geobacillus sp.;

[0015] The deposit institution: China General Microbiological Culture Collection Center;

[0016] The deposit address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, China, Institute of Microbiology, Chinese Academy of Sciences.

[0017] A bacterial agent, the active ingredient of which is the above-mentioned Geobacillus.

[0018] A fermentation broth, which is a liquid obtained after metabolism of the above-mentioned Geobacillus and a nutrient medium, wherein:

[0019] The active ingredient of the fermentation broth is the above-mentioned Geobacillus;

[0020] The nutrient medium is LB medium, and is composed of the following components in terms of mass percentage:

[0021] Peptone 0.5 - 2 wt%, yeast powder 0.3 - 0.8 wt%, sodium chloride 0.5 - 2 wt%, the balance is distilled water, and the pH value is 6.8 - 7.5.

[0022] Furthermore, during fermentation, the inoculation amount is 3 - 10%, the inoculation age is 5 - 15 h, the temperature is 20 - 55 °C, and static culture is carried out for 48 - 120 h.

[0023] The application of Substance I and / or Substance II and / or Substance III in oil exploitation, wherein:

[0024] Substance I is the above-mentioned Geobacillus;

[0025] Substance II is the above-mentioned bacterial agent;

[0026] Substance III is the above-mentioned fermentation broth.

[0027] The application of Substance I and / or Substance II and / or Substance III in treating oilfield sewage, wherein:

[0028] Substance I is the above-mentioned Geobacillus;

[0029] Substance II is the above-mentioned bacterial agent;

[0030] Substance III is the above-mentioned fermentation broth.

[0031] Furthermore, the specific manner of the above application is as follows:

[0032] Substance I, substance II or substance III is added through the chemical dosing port provided on the water intake pipeline of the water station, and directly mixed with the sewage for the degradation of crude oil. The dosing concentration is 100 - 300 mg / L, preferably 200 mg / L.

[0033] Furthermore, the dosing method is continuous dosing.

[0034] A Geobacillus sp. DC-3 and its application disclosed by the present invention have the following beneficial effects:

[0035] 1. The Geobacillus sp. DC-3 provided by the present invention has good degradation ability for the crude oil in the produced water of oilfields, and can degrade the crude oil into metabolites such as carbon dioxide and water;

[0036] 2. When the present invention is applied, there is no need to transform any sewage treatment equipment, and the original chemical dosing port provided on the water intake pipeline of the water station can be directly used, which has good adaptability and low use cost;

[0037] 3. Experimental results show that for the produced water of oilfields treated with Geobacillus sp. DC-3, under the condition of 40 °C, Geobacillus sp. DC-3 can degrade more than 87% of the crude oil content in the produced water of oilfields, greatly improving the water quality. Description of the Drawings

[0038] Figure 1 It is the strain morphology diagram of Geobacillus sp. DC-3 disclosed by the present invention.

[0039] Figure 2 It is the phylogenetic tree of Geobacillus sp. DC-3 disclosed by the present invention.

[0040] Figure 3 It is the temperature tolerance curve of Geobacillus sp. DC-3 disclosed by the present invention.

[0041] Figure 4 It is the salt tolerance curve of Geobacillus sp. DC-3 disclosed by the present invention.

[0042] Figure 5 It is the indoor evaluation result of the crude oil degradation ability of Geobacillus sp. DC-3 disclosed by the present invention.

[0043] Figure 6 It is the process flow diagram of the application of Geobacillus sp. DC-3 disclosed by the present invention in the sewage treatment of Gudao Oil Production Plant in Shengli Oilfield.

[0044] Figure 7 It is the change situation of the oil content in the sewage before and after the application of Geobacillus sp. DC-3 in a certain combined station of Gudao Oil Production Plant in Shengli Oilfield. Detailed Embodiments

[0045] The present invention will be further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto:

[0046] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0047] The nutrient medium described in this application is LB medium, which is composed of the following components in mass percentage:

[0048] Peptone 0.5 - 2 wt%, yeast powder 0.3 - 0.8 wt%, sodium chloride 0.5 - 2 wt%, the balance is distilled water, and the pH value is 6.8 - 7.5.

[0049] Unless otherwise specified, the nutrient medium mentioned refers to the following LB medium:

[0050] Peptone 1 wt%, yeast powder 0.5 wt%, sodium chloride 1 wt%, the balance is distilled water, and the pH value is 6.8 - 7.5.

[0051] The mass percentages of the components of the inorganic salt medium for Geobacillus sp. DC - 3 are as follows: crude oil 0.1 - 2 wt%, NH4Cl 0.05 wt%, KH2PO4 0.2 wt%, Na2CO3 0.05 wt%, MgCl2·6H2O 0.02 wt%, trace element solution 0.02 wt%, and the rest is distilled water (2% agar needs to be added for solid medium), and the pH value is 7.0.

[0052] The mass percentages of the components of the trace element solution are as follows: EDTA 0.005 wt%, FeSO4·7H2O 0.002 wt%, ZnSO4·7H2O 0.1 wt%, MnCl2·4H2O 0.003 wt%, CoCl2·6H2O 0.2 wt%, NiCl2·6H2O 0.02 wt%, Na2MoO4·2H2O 0.03 wt%, CaCl2·2H2O 0.01 wt%, H3BO3 0.3 wt%.

[0053] The performance evaluation parameters of Geobacillus sp. DC - 3 mainly include: growth ability, degradation ability, and the specific evaluation methods are as follows:

[0054] (1) Evaluation of growth ability

[0055] Growth with crude oil as nutrition: Geobacillus sp. DC-3 was inoculated into a nutrient medium, and 5-10 g / L of crude oil was added. Then, it was statically cultured at 40 °C for 2 days, and the bacterial density was measured.

[0056] (2) Evaluation of degradation ability

[0057] Evaluation of the crude oil degradation ability: Geobacillus sp. DC-3 was inoculated into a nutrient medium, and 10 g / L of crude oil was added. Then, it was statically cultured at 40 °C for 2 days. The crude oil after the treatment was subjected to a total hydrocarbon gas chromatography analysis. Using the sum of the chromatographic peak areas of the marker components with carbon numbers less than 20, namely C 17 、C 18 and C 19 , and comparing it with the total sum of the peak areas of the components C 27 、C 28 and C 29 , a parameter reflecting the effective action of Geobacillus sp. DC-3 on crude oil was obtained. The change rate of ∑(C 17+ C 18 +C 19 ) / ∑(C 27 +C 28 +C 29 ) in the alkane of the tested crude oil was measured.

[0058] The initial oil content of the medium can be determined when preparing the medium. The method for measuring the oil content of the medium after the strain treatment is as follows:

[0059] (1) Weigh 0.5000 g of crude oil, dissolve it in petroleum ether in a 100 mL volumetric flask and dilute it to the mark. This solution is used as the standard oil solution with an oil content of 5.0 mg / mL.

[0060] Using a pipette, respectively pipette 0.00 mL, 0.5 mL, 1.00 mL, 1.50 mL, 2.00 mL, 2.50 mL, 3.00 mL of the standard oil solution into 7 50 mL colorimetric tubes, dilute them to the mark with petroleum ether and shake well. Using petroleum ether as the blank, colorimetric analysis is carried out on a spectrophotometer. According to the measured optical density values and the corresponding oil contents, a standard curve is plotted.

[0061] (2) Transfer the culture solution to be tested into a separatory funnel. Use 50 mL of petroleum ether to extract the remaining crude oil in the culture solution twice. Each time, pour the petroleum ether after washing the culture solution bottle into the separatory funnel and shake it Collect the two extraction solutions in a 50 mL colorimetric tube, dilute it to the mark with petroleum ether, tighten the bottle cap and shake well.

[0062] (3) Using petroleum ether as the blank sample, measure its optical density value on a spectrophotometer under the same measurement conditions as in step (1), and find out the oil content from the standard curve.

[0063] (4) It is calculated according to the following formula:

[0064] Oil content (mg / L) = Oil content (mg) found on the standard curve / Volume of extracted water sample (mL) × 1000

[0065] Crude oil degradation rate (%) = (Initial oil content - Residual oil content) / Initial oil content × 100%;

[0066] Example 1: Obtaining and identification of Bacillus geothermicus DC-3

[0067] I. Obtaining of strains

[0068] The inventor isolated a strain from the produced water sample of an oil well in Gudao Oil Production Plant of Shengli Oilfield, named DC-3.

[0069] The specific steps are as follows:

[0070] Take 1 mL of the produced water from Gudao Oil Production Plant of Shengli Oilfield with a disposable syringe and inoculate it into an inorganic salt medium (Composition of the medium: 0.1 - 2 wt% crude oil, 0.05 wt% NH4Cl, 0.2 wt% KH2PO4, 0.05 wt% Na2CO3, 0.02 wt% MgCl2·6H2O, 0.02 wt% trace element solution, the rest is distilled water, pH value 7.0). Under the condition of constant temperature at 40 °C, shake and culture at 100 rdm for 3 d until the culture solution becomes turbid.

[0071] Absorb 2 mL of the turbid culture solution and transfer it into an inorganic salt medium with the same composition. Under the condition of constant temperature at 40 °C, shake and culture at 100 rdm for 3 d. After the culture solution becomes turbid, conduct another subculture.

[0072] After that, use a disposable syringe to absorb 1 mL of the culture solution and add it to sterile water for dilution. The dilution multiples are 10 -5 、10 -6 、10 -7 . Respectively take 200 μL of the diluted culture solution and spread it on a solid nutrient medium (Composition of the medium: 1 wt% peptone, 0.5 wt% yeast powder, 1 wt% sodium chloride, 2 wt% agar, the balance is distilled water, pH value 6.8 - 7.5).

[0073] Cultivate at a constant temperature of 40 °C for 3 d to form single colonies. Transfer different morphological single colonies on the medium into a liquid nutrient medium with the same composition for scale-up culture, and cultivate at a constant temperature of 40 °C for 5 d. Take the culture solution and inoculate it into the solid nutrient medium again, and cultivate at a constant temperature of 40 °C for 3 d to isolate multiple single colonies.

[0074] Inoculate each well-grown single colony into an inorganic salt liquid medium containing 10 g / L of crude oil, and culture it under constant temperature at 40 °C with shaking at 100 rdm for 3 days. Then, screen for strains with strong crude oil degradation ability by detecting the reduction of the oil content in the medium. Finally, obtain a strain DC-3 with the best crude oil degradation effect.

[0075] II. Identification of the Strain

[0076] Figure 1 This is the morphological diagram of the Geobacillus sp. DC-3 disclosed in the present invention. As can be seen from Figure 1 it, the colony morphological characteristics of strain DC-3 are as follows: The colonies that appear after culturing on the solid medium for 1 - 2 days have a diameter of 0.2 - 0.7 mm. The colony morphology is round, with neat edges, a moist and opaque surface, and a light yellow color.

[0077] The cell morphological characteristics of Geobacillus sp. DC-3 are as follows: The cells are Gram-positive after Gram staining, and the cell morphology under the microscope is rod-shaped, as shown in Figure 1 Figure [specific figure number]. The size is (2.0 - 8.5) μm × (0.2 - 0.8) μm, with terminal or subterminal spores and peritrichous flagella.

[0078] III. Physiological and Biochemical Properties

[0079] Refer to the experimental methods in "Bergey’s Mannual of Systematic Bacteriology" to detect its Gram staining, cell size and morphology, growth temperature, growth pH range, and NaCl tolerance. Conduct methyl red, catalase, V-P, glucose acid production, starch hydrolysis, pyocyanin, oxidase experiments, as well as experiments using sucrose, citrate, rhamnose, acetate, lactose, arabinose, galactose, xylose, and inositol.

[0080] The results show that: The strain is Gram-positive, rod-shaped under the microscope, facultatively anaerobic, with a growth temperature of 20 - 55 °C, and the most suitable growth temperature is 40 °C (as shown in Figure 3 Figure [specific figure number]), a growth pH range of 4 - 10, and an NaCl tolerance of 0 - 22% (as shown in Figure 4 Figure [specific figure number]). The catalase and V-P experiments are positive, while the methyl red, glucose acid production, starch hydrolysis, pyocyanin, and oxidase experiments are all negative. It can utilize sucrose, citrate, rhamnose, and xylose, but cannot utilize acetate, lactose, arabinose, galactose, and inositol.

[0081] Some physiological and biochemical characteristics of Geobacillus sp. DC-3 are shown in Table 1:

[0082] Table 1

[0083] Experimental project Result Experimental project Result Gram + Sucrose + Motility + Citrate + Methyl red - Rhamnose + Catalase + Acetate - V-P + Lactose - Glucose acid production - Arabinose - Starch hydrolysis - Galactose - Pyocyanin - Xylose + Oxidase - Inositol -

[0084] Note: "+" indicates a positive reaction and "-" indicates a negative reaction.

[0085] Referring to the content of "Bergey’s Mannual of Systematic Bacteriology", based on its morphological characteristics, physiological and biochemical characteristics, and referring to the alignment results of the 16S rDNA gene sequence of this bacterium in GenBnk, a phylogenetic tree was constructed (as Figure 2 shown) for analysis, and it was identified that DC-3 is a new bacterium belonging to Geobacillus sp.

[0086] IV. Preservation of Geobacillus sp. DC-3

[0087] This strain was deposited on August 9, 2023; the deposit number is: CGMCC No. 28134; the deposit unit: China General Microbiological Culture Collection Center; the deposit address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, China, Institute of Microbiology, Chinese Academy of Sciences; the taxonomic name of this strain is: Geobacillus sp. DC-3.

[0088] Example 2: Experiment on the degradation performance of Geobacillus sp. DC-3 on crude oil.

[0089] 1. Test strain

[0090] Geobacillus sp. DC-3 isolated in Example 1 of the present invention.

[0091] 2. Experimental method

[0092] The test strain was cultured in a nutrient medium until the logarithmic growth phase. Oilfield sewage with an oil content of 100 mg / L was prepared, and the cultured bacterial solution was inoculated into a triangular flask containing 100 ml of oilfield sewage at an inoculation amount of 2%. Multiple control groups were set up, placed in an incubator at 40 °C, and shaken at 100 rdm. The oil content was measured for one group every 12 hours. In the experiment, the original water sample without inoculation treatment was used as a blank control.

[0093] 3. Test results

[0094] The test results are as Figure 5 shown. Under the condition of 40 °C, after the oilfield sewage with an initial oil content of 100 mg / L was treated with the bacterial solution, the oil content decreased to 9.6 mg / L after 72 hours, and the removal effect of this bacterium on crude oil was good.

[0095] Example 3 Application of Geobacillus sp. DC-3 in the sewage treatment of a certain joint station in Gudao Oil Production Plant of Shengli Oilfield.

[0096] 1. Test Strains

[0097] Bacillus geothermus DC-3 isolated in Example 1 of the present invention.

[0098] 2. Sewage Overview

[0099] The sewage treatment volume of a certain combined station in Gudao Oil Production Plant of Shengli Oilfield is 14,000 m 3 / d. The water quality of the sewage before adding Bacillus geothermus DC-3 is shown in Table 2.

[0100] Table 2 Analysis Results of Sewage in Water Injection Station

[0101]

[0102] 3. Implementation Steps

[0103] The on-site application process is to add the bacterial liquid at the chemical dosing port of the water inlet pipeline of the water station without changing the original sewage treatment process, and directly use the mixture of the bacterial liquid and sewage to degrade crude oil. The specific method is: add the fermentation liquid of Bacillus geothermus DC-3 to the sewage at a dosing concentration of 200 mg / L, and the dosing method is continuous dosing. The dosing position is as Figure 6 shown.

[0104] 4. Test Results

[0105] Continuously detect the oil content of the sewage at the outlet of the water station. The results are as Figure 7 shown. Bacillus geothermus DC-3 can effectively degrade the crude oil in the sewage. After on-site test treatment, the oil content in the sewage drops from 157 mg / L to 19.2 mg / L, and the crude oil degradation rate reaches 87.7%. The quality of the exported water is greatly improved.

[0106] The above has made a detailed description of the implementation mode of the present invention. However, the present invention is not limited to the above implementation mode. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the gist of the present invention.

Claims

1. A Geobacillus sp. DC-3, characterized in that, Its preservation number is CGMCC No. 28134.

2. A bacterial agent, characterized in that, Its active ingredient is the Geobacillus sp. described in claim 1.

3. A fermentation broth, characterized in that, It is the liquid after metabolism of the Geobacillus sp. DC-3 described in claim 1 and a nutrient medium, wherein: The active ingredient of the fermentation broth is the Geobacillus sp. DC-3.

4. A fermentation broth according to claim 3, characterized in that, The nutrient medium is LB medium, and by mass percentage, it is composed of the following components: Peptone 0.5 - 2 wt%, yeast powder 0.3 - 0.8 wt%, sodium chloride 0.5 - 2 wt%, the balance is distilled water, and the pH value is 6.8 - 7.

5.

5. A fermentation broth according to claim 4, characterized in that, The nutrient medium is LB medium, and by mass percentage, it is composed of the following components: Peptone 1 wt%, yeast powder 0.5 wt%, sodium chloride 1 wt%, the balance is distilled water, and the pH value is 6.8 - 7.

5.

6. A fermentation broth according to claim 4, characterized in that, During fermentation, the inoculation amount is 3 - 10%, the inoculation age is 5 - 15 h, the temperature is 20 - 55 °C, and it is statically cultured for 48 - 120 h.

7. The application of Substance I and / or Substance II and / or Substance III in oil exploitation, characterized in that: Substance I is the Geobacillus sp. described in claim 1; Substance II is the microbial agent described in claim 2; Substance III is the fermentation broth described in claim 3.

8. The application of Substance I and / or Substance II and / or Substance III in treating oilfield sewage, characterized in that: Substance I is the Geobacillus sp. described in claim 1; Substance II is the microbial agent described in claim 2; Substance III is the fermentation broth described in claim 3.

9. The application according to claim 8, characterized in that, The specific manner of the above application is as follows: Substance I or Substance II or Substance III is added through the chemical addition port provided on the water station inlet pipeline, and it is directly used to mix with sewage for the degradation of crude oil, and its addition concentration is 100 - 300 mg / L.

10. The application according to claim 9, characterized in that, The addition method is continuous addition, and the addition concentration is 200 mg / L.

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