Ozone aeration and microorganism compounded polluted soil and underground water in-situ remediation or management and control method

Abstract

The invention relates to an ozone aeration and microorganism compounded polluted soil and underground water in-situ remediation or management and control method, which comprises the following steps: S1, injecting ozone micro-nano bubbles with a first particle size into soil or underground water, continuously aerating for 1-5 days, aerating for 6-10 hours every day, and ensuring that the first particle size is nanoscale; s2, ozone micro-nano bubbles with the second particle size are injected into soil or underground water, continuous aeration is conducted for 1-5 days, the aeration time every day is 6-10 h, the second particle size is larger than the first particle size, and the second particle size is in the micron order; s3, 2-9 days after the step S2 is completed, air micro-nano bubbles or oxygen micro-nano bubbles with the third particle size are injected into soil or underground water, continuous aeration is conducted for 1-4 days, the aeration time is 6-10 h every day, and the third particle size is in the nanoscale; and S4, injecting a compound microbial agent 12-24 hours after the step S3 is completed.

Description

Technical Field

[0001] The present invention relates to the field of contaminated soil and groundwater treatment, and particularly relates to an in-situ remediation or control method for contaminated soil and groundwater by combining ozone aeration and microorganisms. Background Art

[0002] Ozone is a strong oxidant that can rapidly decompose organic pollutants, and it decomposes into oxygen after completing the oxidation reaction, usually without producing secondary pollution. However, the solubility of ozone is limited and its half-life is short, and continuous supply and injection are required to maintain an effective oxidation reaction. Therefore, the application of ozone in pollutant treatment still needs further research.

[0003] Microbial remediation has the characteristics of being green, environmentally friendly, energy-efficient, capable of in-situ remediation, cost-effective, and able to adapt to the environment for a long time and continuously repair. However, when applied to contaminated soil and sewage treatment, it is difficult to directly utilize because the pollutants in the contaminated soil and sewage are often highly toxic to it. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a new in-situ remediation or control method for contaminated soil and groundwater by combining ozone aeration and microorganisms.

[0005] To solve the above technical problems, the technical solution adopted in the first aspect of the present invention is as follows: An in-situ remediation or control method for contaminated soil and groundwater by combining ozone aeration and microorganisms, comprising the following steps: S1 Inject ozone micro-nano bubbles with a first particle size into the soil or groundwater, and continuously aerate for 1 to 5 days, with the aeration time being 6 to 10 hours per day, and the first particle size is nanoscale; S2 Inject ozone micro-nano bubbles with a second particle size into the soil or groundwater, and continuously aerate for 1 to 5 days, with the aeration time being 6 to 10 hours per day, the second particle size is larger than the first particle size, and the second particle size is micron-scale; S3 After step S2 is completed for 2 to 9 days, inject air micro-nano bubbles or oxygen micro-nano bubbles with a third particle size into the soil or groundwater, and continuously aerate for 1 to 4 days, with the aeration time being 6 to 10 hours per day, and the third particle size is nanoscale; S4 Inject a composite microbial inoculum 12 to 24 hours after step S3 is completed.

[0006] In some specific embodiments, in step S1, continuous aeration is carried out for 1 day, 2 days, 3 days, 4 days or 5 days.

[0007] In some specific embodiments, in step S2, continuous aeration is carried out for 1 day, 2 days, 3 days, 4 days or 5 days.

[0008] In some specific embodiments, in step S3, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, or 9 days after the completion of step S2, air micro-nano bubbles or oxygen micro-nano bubbles with a third particle size are injected into the soil or groundwater.

[0009] In some specific embodiments, in step S3, continuous aeration is carried out for 1 day, 2 days, 3 days, or 4 days.

[0010] In some specific embodiments, in step S4, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h, or 24h after the completion of step S2, a composite microbial inoculum is injected.

[0011] In some specific embodiments, in step S1, the daily aeration time is 6h, 7h, 8h, 9h, or 10h.

[0012] In some specific embodiments, in step S2, the daily aeration time is 6h, 7h, 8h, 9h, or 10h.

[0013] In some specific embodiments, in step S3, the daily aeration time is 6h, 7h, 8h, 9h, or 10h.

[0014] In one embodiment, the first particle size range is 90 - 120nm, and / or the second particle size range is 8 - 12μm.

[0015] In one embodiment, the first particle size range is 95 - 110nm, and / or the second particle size range is 9 - 11μm.

[0016] In one embodiment, the microbial strains in the composite microbial inoculum are all aerobic bacteria.

[0017] In one embodiment, the composite microbial inoculum is used to treat chlorinated hydrocarbon pollutants, and / or the composite microbial inoculum is used to treat petroleum hydrocarbon pollutants.

[0018] In one embodiment, the combination of the composite microbial inoculum is Pseudomonas, Sphingomonas, Rhodococcus, Bacillus, Burkholderia, and the viable bacteria ratio is 1 - 3:1 - 3:1 - 3:1 - 2:1.

[0019] In one embodiment, the combination of the compound microbial inoculum is Pseudomonas, Cupriavidus, Comamonas, Achromobacter, Variovorax, and the viable count ratio is 3 - 8:1 - 3:1 - 2:1 - 2:1.

[0020] In one embodiment, the combination of the compound microbial inoculum is Rhodococcus, Sphingobium, Arthrobacter, Stenotrophomonas, Mycobacterium, and the viable count ratio is 2 - 6:2 - 4:2 - 4:1 - 2:1.

[0021] In one embodiment, the combination of the compound microbial inoculum is Bacillus, Alcaligenes, Ochrobactrum, Methylobacterium, Dechloromonas, and the viable count ratio is 4 - 10:2 - 4:1 - 3:1 - 2:1.

[0022] In one embodiment, the combination of the compound microbial inoculum is Pseudomonas, Paenibacillus, Hyphomicrobium, Nocardia, Flavobacterium, and the viable count ratio is 3 - 8:1 - 3:1 - 2:1 - 2:1.

[0023] In one embodiment, the combination of the compound microbial inoculum is Pseudomonas, Rhodococcus, Bacillus, Alcaligenes, Acinetobacter, and the viable count ratio is 4 - 10:2 - 4:1 - 3:1 - 2:1.

[0024] In one embodiment, the combination of the compound microbial inoculum is Sphingomonas, Mycobacterium, Burkholderia, Streptomyces, Paracoccus, and the viable count ratio is 2 - 6:2 - 4:2 - 4:1 - 2:1.

[0025] In one embodiment, the combination of the composite microbial agent is Pseudomonas, Rhodococcus, Bacillus, Acinetobacter, and Arthrobacter, and the viable cell count ratio is 1-3:1-3:1-3:1-2:1.

[0026] In one embodiment, the viable cell count concentration of the composite microbial agent is not less than 1×10 9 CFU / mL.

[0027] In one embodiment, the micro-nano bubbles and the composite microbial agent are injected through the same point; or, the injection point of the composite microbial agent is downstream of the injection point of the micro-nano bubbles and the distance from the injection point of the micro-nano bubbles is less than or equal to 1 m. Here, the downstream is defined relative to the direction of the groundwater field.

[0028] In one embodiment, the pollutants in the contaminated soil or groundwater are one or more of chlorinated hydrocarbons, benzene series, polychlorinated biphenyls, organic pesticides, and phenols.

[0029] In one embodiment, the pollutants in the contaminated soil or groundwater exist in the form of non-aqueous phase liquids NAPL, and the non-aqueous phase liquids include light non-aqueous phase liquids LNAPL and heavy non-aqueous phase liquids DNAPL.

[0030] In one embodiment, 60-135 days after step S4, the pollutant content in the groundwater is 0.4-2000 μg / L.

[0031] In one embodiment, 45-135 days after step S4, the pollutant content in the soil is less than 560 mg / kg.

[0032] In one embodiment, taking every 5 m depth of the soil or groundwater as a unit, in step S1, the ozone micro-nano bubbles with the first particle size are injected to a depth of 4-6 m in each unit, and / or in step S2, the ozone micro-nano bubbles with the second particle size are injected to a depth of 4-6 m in each unit, and / or in step S3, the air micro-nano bubbles or oxygen micro-nano bubbles with the third particle size are injected to a depth of 4-6 m in each unit.

[0033] In one embodiment, when the repair object is the groundwater, 0-24 h after step S3, the pollutant concentration is less than 200 mg / L.

[0034] In one embodiment, when the repair object is the groundwater, 0-24 h after step S3, the pollutant concentration is less than 150 mg / L.

[0035] In one embodiment, when the object to be repaired is the groundwater, within 0 to 24 hours after step S3 is completed, the pollutant concentration is less than 100 mg / L.

[0036] In one embodiment, when the object to be repaired is the groundwater, within 0 to 24 hours after step S3 is completed, the microbial biomass is less than 2×10 6 CFU / ml.

[0037] In one embodiment, when the object to be repaired is the groundwater, within 0 to 24 hours after step S3 is completed, the microbial biomass is less than 1×10 6 CFU / ml.

[0038] In one embodiment, when the object to be repaired is the groundwater, within 0 to 24 hours after step S3 is completed, the redox potential is less than 300 mV.

[0039] In one embodiment, when the object to be repaired is the groundwater, within 0 to 24 hours after step S3 is completed, the redox potential is less than 250 mV.

[0040] In one embodiment, when the object to be repaired is the groundwater, within 0 to 24 hours after step S3 is completed, the redox potential is greater than 200 mV.

[0041] In one embodiment, when the object to be repaired is the soil, within 0 to 24 hours after step S3 is completed, the concentration of recalcitrant pollutants is less than 1000 mg / kg.

[0042] In one embodiment, when the object to be repaired is the soil, within 0 to 24 hours after step S3 is completed, the concentration of recalcitrant pollutants is less than 800 mg / kg.

[0043] In one embodiment, when the object to be repaired is the soil, within 0 to 24 hours after step S3 is completed, the microbial biomass is less than 1.5×10 8 CFU / g.

[0044] In one embodiment, when the object to be repaired is the soil, within 0 to 24 hours after step S3 is completed, the microbial biomass is less than 1×10 8 CFU / g.

[0045] In one embodiment, the soil environment is one or more of silt, clay, silty clay, silty sand or sandy soil.

[0046] To solve the above technical problems, the technical solution adopted in the second aspect of the present invention is: An in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism combination, characterized by comprising the following steps: S1 Inject ozone micro-nano bubbles with the first particle size into the soil or groundwater, and conduct continuous aeration for 1 to 5 days, with the daily aeration time being 6 to 10 hours. The first particle size is at the nano level; S2 Inject ozone micro-nano bubbles with the second particle size into the soil or groundwater, and conduct continuous aeration for 1 to 5 days, with the daily aeration time being 6 to 10 hours. The second particle size is larger than the first particle size, and the second particle size is at the micron level; S3 Inject a composite microbial agent 12 to 24 hours after step S2 is completed.

[0047] In one embodiment, the range of the first particle size is 90 to 120 nm, and / or the range of the second particle size is 8 to 12 μm.

[0048] In one embodiment, the composite microbial agent is an aerobic bacterium and / or an anaerobic bacterium.

[0049] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: 1. By setting ozone micro-nano bubbles, the oxidizing property and solubility of ozone are enhanced, and the residence time of ozone in the contaminated soil or groundwater is increased; the properties of ozone micro-nano bubbles are used to treat pollutants; the bactericidal property of ozone and the oxygen generated after ozone reaction are used to regulate the environmental conditions of the contaminated soil or groundwater, and microorganisms are enhanced / activated; 2. By combining ozone micro-nano bubbles with microorganisms, microorganisms are used for continuous environmental remediation or risk control of pollution source reduction, making the treatment of pollutants in the contaminated soil or groundwater more thorough; 3. By sequentially injecting ozone micro-nano bubbles with the first particle size at the nano level and ozone micro-nano bubbles with the second particle size at the micron level, and specifically setting the aeration time and the interval time, a composite microbial agent injection point is formed. This injection point not only uses ozone micro-nano bubbles to remove some microorganisms and pollutants in the contaminated soil or groundwater, but also does not allow the residual ozone to affect the activity of the subsequently injected composite microbial agent, enabling the subsequent composite microbial agent to survive and reproduce smoothly; 4. By reasonably setting the injection sequence, aeration time and interval time of ozone micro-nano bubbles with different particle sizes, the pretreatment time of the contaminated soil or groundwater before the injection of the composite microbial agent is maximally shortened, and the treatment efficiency of the contaminated soil or groundwater is improved. Detailed implementation method

[0050] In one embodiment, the in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism combination of the present invention includes the following steps: S1 Inject ozone micro-nano bubbles with the first particle size into the soil or groundwater, and conduct continuous aeration for 1 to 5 days, with the daily aeration time being 6 to 10 hours. The first particle size is at the nano level; S2 Inject ozone micro-nano bubbles with a second particle size into the soil or groundwater, and continuously aerate for 1 to 5 days, with an aeration time of 6 to 10 hours per day. The second particle size is larger than the first particle size, and the second particle size is in the micron range. S3 After 2 to 9 days from the completion of step S2, inject air micro-nano bubbles or oxygen micro-nano bubbles with a third particle size into the soil or groundwater, and continuously aerate for 1 to 4 days, with an aeration time of 6 to 10 hours per day. The third particle size is in the nano range. S4 Inject a composite microbial inoculum 12 to 24 hours after the completion of step S3.

[0051] Furthermore, the microbial strains in the composite microbial inoculum are aerobic bacteria. That is, in this embodiment, air micro-nano bubbles or oxygen micro-nano bubbles are aerated in step S3 after step S2, which is suitable for the survival environment of aerobic bacteria.

[0052] Furthermore, aerobic bacteria can be divided into two major categories according to the target pollutants they are directed against: chlorinated hydrocarbon aerobic bacteria for treating chlorinated hydrocarbon pollutants and petroleum hydrocarbon aerobic bacteria for treating petroleum hydrocarbon pollutants.

[0053] The chlorinated hydrocarbon aerobic bacteria can have the following combinations: Combination 1: Pseudomonas, Sphingomonas, Rhodococcus, Bacillus, Burkholderia, with a viable cell number ratio of 1 to 3:1 to 3:1 to 3:1 to 2:1; Combination 2: Pseudomonas, Cupriavidus, Comamonas, Achromobacter, Variovorax, with a viable cell number ratio of 3 to 8:1 to 3:1 to 2:1 to 2:1; Combination 3: Rhodococcus, Sphingobium, Arthrobacter, Stenotrophomonas, Mycobacterium, with a viable cell number ratio of 2 to 6:2 to 4:2 to 4:1 to 2:1; Combination Four: Bacillus, Alcaligenes, Ochrobactrum, Methylobacterium, Dechloromonas, with the viable cell count ratio being 4 - 10:2 - 4:1 - 3:1 - 2:1; Combination Five: Pseudomonas, Paenibacillus, Hyphomicrobium, Nocardia, Flavobacterium, with the viable cell count ratio being 3 - 8:1 - 3:1 - 2:1 - 2:1.

[0054] The aerobic petroleum - degrading bacteria can have the following combinations: Combination One: Pseudomonas, Rhodococcus, Bacillus, Alcaligenes, Acinetobacter, with the viable cell count ratio being 4 - 10:2 - 4:1 - 3:1 - 2:1; Combination Two: Sphingomonas, Mycobacterium, Burkholderia, Streptomyces, Paracoccus, with the viable cell count ratio being 2 - 6:2 - 4:2 - 4:1 - 2:1; Combination Three: Pseudomonas, Rhodococcus, Bacillus, Acinetobacter, Arthrobacter, with the viable cell count ratio being 1 - 3:1 - 3:1 - 3:1 - 2:1.

[0055] Commonalities of the composite microbial inoculant combinations: (1) Commonalities of the aerobic chloro - hydrocarbon - degrading bacteria: Rely on oxygen as the electron acceptor, catalyze the oxidation reaction of chloro - hydrocarbons through monooxygenase or dioxygenase, cleave the C - Cl bond and generate low - toxicity intermediate products (such as chloroethanol, chloroacetic acid). And co - metabolic substrates (such as toluene, phenol) are required to induce the expression of dehalogenase, and coenzymes (NADH / FADH2) provide the reducing power to drive the reaction. In addition, they are good at degrading low - chlorinated aliphatic hydrocarbons (such as chloroethane) and aromatic hydrocarbons (chlorobenzene) and have strong tolerance to highly chlorinated compounds (such as tetrachloroethylene), and secrete lipase to assist in the degradation of hydrophobic pollutants.

[0056] (2) Common characteristics of aerobic petroleum hydrocarbon bacteria: They can usually rely on oxygenases (such as CYP450, AlkB monooxygenase, PAH dioxygenase) to oxidize alkanes and aromatic hydrocarbons (such as n-alkanes, polycyclic aromatic hydrocarbons PAHs). And they can decompose long-chain hydrocarbons into acetyl coenzyme A through the β-oxidation pathway and enter the tricarboxylic acid cycle (TCA) to be completely mineralized into CO2 and H2O. In addition, they can secrete biosurfactants (such as rhamnolipids, trehalose lipids) to emulsify petroleum and improve its bioavailability. They can also form biofilms by secreting extracellular polysaccharides (EPS) to enhance the adhesion and degradation efficiency at the oil-water interface.

[0057] In one embodiment, the in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism complex of the present invention comprises the following steps. S1 Inject ozone micro-nano bubbles with the first particle size into the soil or groundwater, and continuously aerate for 1 - 5 days, with the aeration time of 6 - 10 hours per day. The first particle size is nanoscale. S2 Inject ozone micro-nano bubbles with the second particle size into the soil or groundwater, and continuously aerate for 1 - 5 days, with the aeration time of 6 - 10 hours per day. The second particle size is larger than the first particle size, and the second particle size is micron-scale. S3 Inject the composite microbial inoculant 12 - 24 hours after the completion of step S2.

[0058] Further, the microbial strains in the composite microbial inoculant are aerobic bacteria and / or anaerobic bacteria. That is, in this embodiment, it is not necessary to carry out air micro-nano bubble or oxygen micro-nano bubble aeration after step S2. Compared with carrying out air micro-nano bubble or oxygen micro-nano bubble aeration after step S2, this embodiment is applicable when the microbial strains in the composite microbial inoculant are anaerobic bacteria, or when the microbial strains in the composite microbial inoculant are aerobic bacteria and the oxygen content in the environment is relatively high, such as the contaminated soil is shallow soil or sandy soil.

[0059] The present invention will be further described below in conjunction with embodiments. However, the present invention is not limited to the following embodiments. The implementation conditions adopted in the embodiments can be further adjusted according to different requirements of specific use, and the implementation conditions not specified are the conventional conditions in this industry. The technical features involved in various embodiments of the present invention can be combined with each other as long as they do not conflict with each other. Unless otherwise specified, the reagents in this application can be obtained commercially or prepared by known methods in the art.

[0060] Examples 1 - 2: The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism complex of Example 1 comprises the following steps: S1 Inject ozone micro-nano bubbles with the first particle size into groundwater through single-point injection. The injection depth is 5 m, continuous aeration is carried out for 3 days, and the aeration time per day is 8 h. The first particle size is 100 nm; S2 Inject ozone micro-nano bubbles with the second particle size into groundwater through single-point injection. The injection depth is 5 m, continuous aeration is carried out for 3 days, and the aeration time per day is 8 h. The second particle size is 100 μm; S3 Seven days after step S2 is completed, inject air micro-nano bubbles with the third particle size into groundwater through single-point injection. Continuous aeration is carried out for 3 days, and the aeration time per day is 8 h. The third particle size is 100 nm; S4 Twenty-four hours after step S3 is completed, inject a composite microbial agent at a single point. The specific composition of the composite microbial agent is Pseudomonas, Sphingomonas, Rhodococcus, Bacillus, Burkholderia. The viable cell number ratio is 2:2:2:1:1, and the viable cell number concentration is 1×10 9 CFU / mL. Specifically, the composite microbial agent is a composite microbial fermentation broth, which is obtained by mixing the fermentation broths of the above strains. When in use, the fermentation broth is diluted 10 times, and about 200 L of the diluted bacterial solution is injected at each point. In this example, the injection points of the micro-nano bubbles in steps S1 to S3 and the composite microbial agent in step S4 are injected through the same point.

[0061] The method for in-situ remediation or control of contaminated soil and groundwater by ozone aeration and microorganism compounding in Example 2 includes the following steps: S1 Inject ozone micro-nano bubbles with the first particle size into contaminated soil through single-point injection. The injection depth is 5 m, continuous aeration is carried out for 3 days, and the aeration time per day is 8 h. The first particle size is 100 nm; S2 Inject ozone micro-nano bubbles with the second particle size into contaminated soil through single-point injection. The injection depth is 5 m, continuous aeration is carried out for 3 days, and the aeration time per day is 8 h. The second particle size is 100 μm; S3 Seven days after step S2 is completed, inject air micro-nano bubbles with the third particle size into contaminated soil through single-point injection. Continuous aeration is carried out for 3 days, and the aeration time per day is 8 h. The third particle size is 100 nm; S4 Twenty-four hours after step S3 is completed, inject a composite microbial agent at a single point, specifically Pseudomonas, Sphingomonas, Rhodococcus, Bacillus, Burkholderia. The viable cell number ratio is 2:2:2:1:1, and the viable cell number concentration is 1×109 CFU / mL. Specifically, the compound microbial inoculum is a compound microbial fermentation broth, which is obtained by mixing the fermentation broths of the above strains. When in use, the fermentation broth is diluted 10 times, and about 200 L of the diluted bacterial solution is injected into each point.

[0062] The main difference between Example 2 and Example 1 is that, compared with Example 1 which treats groundwater pollution, Example 2 treats polluted soil.

[0063] Among them, the aeration equipment in Examples 1 to 2 is a micro-nano bubble generating integrated equipment, the RJN-MN-1100 engineering type (including ozone generating device) of Shanghai Runjing Environmental Protection Technology Co., Ltd. The specific parameters of this machine are as follows: Bubble water output: 1.8 T / h; Working pressure: 0.4 - 0.5 MPa; Intake air flow: 0.1 - 2.5 L / min (standard condition). Adopting gas-liquid dissolution technology, cooperating with a nozzle for precise shearing to generate bubble water, micro-nano bubbles with a minimum median particle size of 120 - 90 nm can be generated, and the bubble concentration can reach 2 - 5×10 8 per mL, the standard oxygen mass transfer efficiency SOTE can reach 82 - 85%, the potential of nano-bubbles is -58.4 - -59.6 mV, and the properties of nano-bubbles are stable.

[0064] Supplementary parameters of the ozone generator: The ozone generation concentration is 35 - 70 mg / L, and the generation amount meets the intake air flow requirements.

[0065] Geological exploration was carried out on the soil where Examples 1 to 2 are located. The soil is mainly composed of silty clay, silt and silty sand. The characteristics are described as follows from top to bottom: ① Layer of plain fill: mainly light gray and light grayish-yellow silt, very wet, slightly dense, occasionally with a small amount of gravel, uneven in composition and density, and poor in structure. This layer is distributed locally in the site, with a thickness of 1.00 - 3.40 m and an average of 1.99 m.

[0066] ② Layer of silt: light grayish-yellow and light gray, soft plastic, medium dense, no luster on the cut surface, low dry strength and toughness, and obvious water separation by shaking. This layer covers the site, with a thickness of 16.90 - 18.70 m and an average of 17.97 m.

[0067] ③ Layer of silty sand: bluish-gray, saturated, medium dense - dense, mainly mineral components quartz and feldspar, containing mica flakes, particle shape sub-round and angular, poor particle gradation, no dry strength and toughness, and rapid shaking reaction. This layer is distributed throughout the site.

[0068] Pilot test result detection Sampling: Samples were taken from the contaminated soil and groundwater treated by the in-situ remediation or control method of sewage with ozone aeration and microorganism compounding in Examples 1 to 2. The sampling points for each example were 1 m and 5 m horizontally from the aeration point. A total of 7 samplings were conducted, and the sampling times were 0 d (before aeration), 3 d (the same day after completing Step S1), 6 d (the same day after completing Step S2), 9 d (3 days after completing Step S2), 13 d (7 days after completing Step S2), 16 d (the same day after completing Step S3), and 17 d (1 day after completing Step S3, the node before the addition of the compound microorganism agent).

[0069] Detection indicators: There are four categories of detection indicators for Example 1, namely the concentration of recalcitrant pollutants, microbial biomass, dissolved oxygen concentration, and oxidation-reduction potential ORP. There are two categories of detection indicators for Example 2, namely the concentration of recalcitrant pollutants and microbial biomass.

[0070] Among them, the detection method for the concentration of recalcitrant pollutants is: purge and trap / gas chromatography-mass spectrometry. The recalcitrant pollutant detected in Examples 1 and 2 is o-dichlorobenzene. In Example 1, it was specifically determined according to "Determination of Volatile Organic Compounds - Purge and Trap / Gas Chromatography-Mass Spectrometry" (HJ639-2012), and in Example 2, it was specifically determined according to "Determination of Volatile Organic Compounds - Purge and Trap / Gas Chromatography-Mass Spectrometry" (HJ605-2011).

[0071] Among them, the detection method for microbial biomass is: plate counting method. In Examples 1 and 2, it was specifically determined according to "Determination of Total Bacteria Count in Water Quality - Plate Counting Method" (HJ1000-2018).

[0072] Among them, the detection method for dissolved oxygen concentration is: electrochemical probe method. In Example 1, it was specifically determined according to "Determination of Dissolved Oxygen in Water Quality - Electrochemical Probe Method" (HJ506-2009).

[0073] Among them, the detection method for oxidation-reduction potential ORP is: potentiometry. In Example 1, it was specifically determined according to SL 94-1994 Determination of Oxidation-Reduction Potential (Potentiometry).

[0074] The specific detection results are as follows:

[0075]

[0076]

[0077]

[0078]

[0079]

[0080] Pilot test conclusion 1. Preliminary oxidation of refractory pollutants As can be seen from Table 1-1 and Table 1-2, the pollution concentrations at 0 d are all relatively high; at 3 d, the concentrations at 1 m and 5 m both decrease, and the decrease amplitude at 1 m is greater; at 6 d, the pollution concentrations at 1 m and 5 m further decrease to the same level, and then the concentration in Example 1 rebounds, while the concentration in Example 2 continues to decrease.

[0081] In Example 1, the pollutant concentration is treated to the level of 100 mg / L after 6 d, and in Example 2, the pollutant concentration is treated to the level of 900 mg / kg after 6 d, which basically meets the pollution concentration range for efficient microbial treatment.

[0082] The pollutant concentration in Example 1 at 17 d is slightly higher than that at 6 d, but still remains below the level of 150 mg / L. The pollutant concentration in Example 2 at 17 d is slightly lower than that at 6 d, remaining below the level of 800 mg / kg.

[0083] 2. Inhibition of indigenous microorganisms As can be seen from Table 2-1 and Table 2-2, the amounts of indigenous microorganisms at 0 d are all relatively high; at 3 d, the amounts of microorganisms at 1 m and 5 m both decrease, and the decrease amplitude at 1 m is greater, with an obvious antibacterial effect; at 6 d, the amounts of microorganisms at 1 m and 5 m further decrease to the same level, and then (at 13 d) the amount of microorganisms in Example 1 is basically stable at 3×10 5 CFU / ml level, and the amount of microorganisms in Example 2 is basically stable at 8×10 7 CFU / g level.

[0084] The inhibition effect of ozone micro-nano bubble aeration in Examples 1-2 on indigenous microorganisms is excellent. Basically, after a period of time (at 13 d) after completing Step S2, the amount of microorganisms in Example 1 can be controlled below the level of 5×10 5 CFU / ml, and the amount of microorganisms in Example 2 can be controlled below the level of 10×10 7 CFU / g. Due to the short observation time, no time point of obvious rebound of the amount of microorganisms is observed.

[0085] The amount of microorganisms in Example 1 at 17 d is slightly higher than that at 13 d, but still remains below the level of 20×10 5 CFU / ml, and the amount of microorganisms in Example 2 at 17 d is slightly higher than that at 13 d, remaining below the level of 10×10 7 CFU / g.

[0086] 3. Construction of aerobic environment As can be seen from Table 3, the in-situ environment was anaerobic at 0 d; the oxygen contents at 1 m and 5 m increased at 3 d, and the increase at 1 m was greater; the oxygen contents at 1 m and 5 m further increased to the same level at 6 d and then gradually decreased. At 16 d, due to the aeration of air micro-nano bubbles or oxygen micro-nano bubbles in Step S3, the oxygen content increased.

[0087] 4. Residual time of ozone As can be seen from Table 4, the in-situ environment was slightly oxidized at 0 d; the oxidizing properties at 1 m and 5 m increased at 3 d, and the increase at 1 m was greater; the oxidizing properties at 1 m and 5 m further increased to the same level at 6 d, up to 860 mV at most; then they gradually decreased, and the oxidizing property dropped back to the level of 250 mV at 13 d.

[0088] The oxidation of pollutants by ozone micro-nano bubble aeration was intense in a short period of time after the aeration was completed, that is, at 6 d, but the duration was not long. It can be considered that only a very small amount of ozone remained at 17 d when the compound microbial agent was added. This is mainly because of the designed use of ozone micro-nano bubble aeration in Step S1 and Step S2, which is required to avoid the adverse effects of ozone micro-nano bubbles on the subsequent process (the addition of exogenous compound microbial agent). Correspondingly, the oxidizing property (ORP value) in the environment dropped to a certain level at a controllable time node.

[0089] Examples 3-4 and Comparative Examples 1-2: The steps of the in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism combination in Example 3 are exactly the same as those in Example 1. The steps of the in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism combination in Example 4 are exactly the same as those in Example 2. The difference between the steps of the in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism combination in Comparative Example 1 and Example 3 is that in Comparative Example 1, Steps S1 and S2 are changed to: injecting ozone micro-nano bubbles with the first particle size into the groundwater through a single point, the injection depth is 5 m, continuous aeration for 6 days, and the aeration time per day is 8 h. The first particle size is 100 nm. The difference between the steps of the in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism combination in Comparative Example 2 and Example 4 is that in Comparative Example 2, Steps S1 and S2 are changed to: injecting ozone micro-nano bubbles with the first particle size into the contaminated soil through a single point, the injection depth is 5 m, continuous aeration for 6 days, and the aeration time per day is 8 h. The first particle size is 100 nm.

[0090] Result detection Sampling: Samples were taken from the sewage treated by the in-situ sewage remediation or control method combining ozone aeration and microorganisms in Examples 3-4 and Comparative Examples 1-2. The sampling points for each example were 1 m and 5 m horizontally from the aeration point, and a total of 7 samplings were carried out. The sampling times were 13 d (7 d after completing Step S2), 16 d (the same day after completing Step S3), 20 d (3 days after completing Step S4), 32 d (15 days after completing Step S4), 47 d (30 days after completing Step S4), 62 d (45 days after completing Step S4), 92 d (75 days after completing Step S4), 122 d (105 days after completing Step S4), and 152 d (135 days after completing Step S4).

[0091] Detection indicators: There are three categories of detection indicators for Example 3 and Comparative Example 1, namely the concentration of recalcitrant pollutants, the amount of microorganisms, and the oxidation-reduction potential ORP. There are two categories of detection indicators for Example 4 and Comparative Example 2, namely the concentration of recalcitrant pollutants and the amount of microorganisms. The detection methods are the same as those in Examples 1-2.

[0092] The specific detection results are as follows:

[0093]

[0094]

[0095]

[0096]

[0097] Pilot test conclusion 1. Proliferation of compound microbial agents As can be seen from Tables 5-1 and 5-2, the in-situ microbial biomass was relatively low before the injection of the compound microbial agent (13 d, 16 d). The microbial biomass at 16 d indicates that even though air micro-nano bubble aeration was carried out for three days subsequently, the antibacterial effect at the point of Comparative Example 1 was still higher than that at the point of Example 3, and the antibacterial effect at the point of Comparative Example 2 was still higher than that at the point of Example 4. Considering only the antibacterial effect, the scheme of Comparative Example 1 is superior to that of Example 3, and the scheme of Comparative Example 2 is superior to that of Example 4.

[0098] However, by comparing the data in Table 5-1 after the injection of the composite microbial inoculant (20d - 152d), it can be found that the microbial growth process at the point of Comparative Example 1 did not start immediately after injection, but was delayed for a period of time. Combining with the change of groundwater ORP value (reflecting ozone residue) in Table 7, it is speculated that the residual ozone at the point of Comparative Example 1 not only continuously inhibited the in-situ microorganisms, but also inhibited the externally added composite microbial inoculant, resulting in a biochemical shock at the initial stage of the addition of the composite microbial inoculant, thus affecting the initial growth and competition of exogenous microorganisms. In the long term (122d, 152d), this effect will not reduce the peak value of the microbial quantity, but will significantly delay it. That is, to increase the exogenous microbial quantity to the same value, the time required for Comparative Example 1 is significantly longer than that of Example 3.

[0099] By comparing the data in Table 5-2 after the injection of the composite microbial inoculant (20d - 152d), it can be found that the microbial growth process at the point of Comparative Example 2 did not start immediately after injection, but was delayed for a period of time. It is speculated that the residual ozone at the point of Comparative Example 1 not only continuously inhibited the in-situ microorganisms, but also inhibited the externally added composite microbial inoculant, resulting in a biochemical shock at the initial stage of the addition of the composite microbial inoculant, thus affecting the initial growth and competition of exogenous microorganisms. In the long term (92d, 122d, 152d), this effect will not reduce the peak value of the microbial quantity, but will significantly delay it. The peak value of the microbial quantity in Example 3 appeared around 92d, and the peak value of the microbial quantity in Comparative Example 2 appeared after 152d. That is, to increase the exogenous microbial quantity to the same value, the time required for Comparative Example 2 is significantly longer than that of Example 4.

[0100] To prevent disturbing the groundwater or soil before injecting the composite microbial inoculant, the microbial quantity at 17d of Examples 3 - 4 was not detected. According to the microbial quantity data at 13d - 17d in Examples 1 - 2, it is speculated that the microbial quantity before injecting the composite microbial inoculant (17d) in steps S4 of Examples 3 - 4 slightly increased or remained basically the same compared with 13d - 16d.

[0101] 2. Microbial treatment of refractory pollutants As can be seen from Table 6-1, the in-situ remediation or control method of contaminated soil and groundwater by ozone aeration and microorganism combination of the present invention has a significant impact on groundwater treatment. In Example 3, the pollutant concentration had dropped below 2.0 mg / L (Class IV water standard) between 122 - 152d, and reached the level of 0.6 mg / L (Class III water standard) at 152d. However, in Comparative Example 1, it still did not reach below 2.0 mg / L at 152d. Due to the short experimental time, the time point when the point of Comparative Example 1 reached the Class IV water standard was not observed, and it is speculated that this point may appear in the range of 182d - 212d.

[0102] As can be seen from Table 6-2, the in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism compounding of the present invention does have a significant impact on the treatment of contaminated soil. In Example 4, the pollutant concentration had dropped below 560 mg / kg (screening value for the first type of land use) between 47 and 62 days. However, in Comparative Example 2, it still did not fully reach below 560 mg / kg until 92 days, and dropped below 560 mg / kg (screening value for the first type of land use) between 92 and 122 days.

[0103] The reason is that the initial impact of ozone residue will cause the added compound microbial inoculant to be biochemically shocked, resulting in a decrease in subsequent survival rate and instantaneous effective concentration. This means that the actual initial concentration and initial proliferation rate of the compound microbial inoculant at the site of Comparative Example 1 are lower than those at the site of Example 3, and the actual initial concentration and initial proliferation rate at the site of Comparative Example 2 are lower than those at the site of Example 4. The decrease in the remediation efficiency of Comparative Example 1 compared to Example 3 and Comparative Example 2 compared to Example 4 is due to the impact on the rate of microbial proliferation and the accumulation time after the microorganisms reach the peak.

[0104] To prevent disturbing the groundwater or soil before injecting the compound microbial inoculant, the detection of recalcitrant pollutants at 17 days in Examples 3 to 4 was not carried out. Based on the data of recalcitrant pollutants at 13 to 17 days in Examples 1 to 2, it is speculated that the recalcitrant pollutants before injecting the compound microbial inoculant (at 17 days) in step S4 of Examples 3 to 4 slightly decreased or remained basically the same compared to 13 to 16 days.

[0105] Examples 5 to 6: The main differences in the steps of the in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism compounding between Example 5 and Example 1 are as follows. In Example 5, steps S1 to S3 are respectively: S1 Inject ozone micro-nano bubbles with the first particle size into the groundwater through single-point injection, the injection depth is 5 m, continuous aeration for 1 day, and the aeration time per day is 8 h, and the first particle size is 100 nm; S2 Inject ozone micro-nano bubbles with the second particle size into the groundwater through single-point injection, the injection depth is 5 m, continuous aeration for 1 day, and the aeration time per day is 8 h, and the second particle size is 100 μm; S3 Four days after step S2 is completed, inject air micro-nano bubbles or oxygen micro-nano bubbles with the third particle size into the groundwater, continuous aeration for 2 days, and the aeration time per day is 6 to 10 h, and the third particle size is 100 nm.

[0106] The main difference between the steps of the in-situ remediation or control method for contaminated soil and groundwater combined with ozone aeration and microorganisms in Example 6 and Example 2 is that steps S1~3 of Example 6 are respectively: S1. Injecting ozone micro-nano bubbles of a first particle size into the contaminated soil through a single point, the injection depth is 5m, aeration is continuous for 1 day, the aeration time is 8h per day, and the first particle size is 100nm; S2. Injecting ozone micro-nano bubbles of a second particle size into the contaminated soil through a single point, the injection depth is 5m, aeration is continuous for 1 day, the aeration time is 8h per day, and the second particle size is 100μm; S3. Four days after step S2 is completed, injecting air micro-nano bubbles or oxygen micro-nano bubbles of a third particle size into the soil, aerating continuously for 2 days, the aeration time is 6~10h per day, and the third particle size is 100nm.

[0107] The soil in Examples 5-6 was surveyed and found to be sandy soil. The characteristics are described from top to bottom as follows: ① Layer of plain fill soil: grayish yellow, wet, loose, with more plant roots and stems on the surface, mainly clay, uneven soil quality, and generally distributed.

[0108] ② Layer of silty clay: gray, saturated, plastic, with a small amount of thin silt layers in some places (single layer thickness varies from 3 to 5 cm), slightly shiny, no shaking reaction, medium dry strength, medium toughness, uneven soil quality, and widespread distribution.

[0109] ③ Layer of sandy silt: gray, wet to very wet, slightly dense to medium dense, with a small amount of clay strips (single layer thickness 1-20mm) and silt lumps, low dry strength, low toughness, no gloss reaction, rapid shaking reaction, uneven soil quality, and local distribution.

[0110] ④ Layer silt sand: gray, saturated, medium-dense to dense, mainly composed of quartz, mica and feldspar. The particle grading is relatively uniform, with clumps of silt, and the soil is uneven and widely distributed.

[0111] ⑤ Layer of sandy silt: gray, wet, medium dense, with a small amount of clay strips (single layer thickness 1-20mm) and silt lumps, low dry strength, low toughness, no gloss reaction, rapid shaking reaction, uneven soil quality, and widespread distribution.

[0112] ⑥ Layer of silt sand: gray, saturated, dense, mainly composed of quartz, mica and feldspar, with relatively uniform particle grading, intercalated silt clumps, and uneven soil quality.

[0113] Pilot test results Sampling: Samples were taken from the contaminated soil and groundwater treated by the in-situ remediation or control method of ozone aeration combined with microorganisms in Examples 5 to 6. The sampling points for each example were located 1 m and 5 m horizontally from the aeration point. A total of 6 samplings were conducted, and the sampling times were 0 d (before aeration), 1 d (the same day after completing Step S1), 2 d (the same day after completing Step S2), 6 d (4 days after completing Step S2), 8 d (the same day after completing Step S3), and 9 d (1 day after completing Step S3, the node before the injection of the composite microbial agent).

[0114] Detection indicators: The detection indicators in Example 5 were the concentrations of recalcitrant pollutants, microbial biomass, dissolved oxygen concentration, and oxidation-reduction potential ORP. The detection indicators in Example 6 were divided into two categories, namely the concentrations of recalcitrant pollutants and microbial biomass. The detection methods were the same as those in Examples 1 to 2.

[0115] The specific detection results are as follows:

[0116]

[0117]

[0118]

[0119]

[0120]

[0121] Pilot-scale test conclusions 1. Preliminary oxidation of recalcitrant pollutants As can be seen from Table 8-1 and Table 8-2, the pollution concentrations at 0 d were relatively high. At 1 d, the concentrations at 1 m and 5 m both decreased, with a greater decrease at 1 m. At 2 d, the pollution concentrations at 1 m and 5 m further decreased to the same level, and then the concentrations rebounded.

[0122] In Example 5, the pollutants were treated to a level below 100 mg / L at 2 d, and in Example 6, the pollutants were treated to a level below 900 mg / kg at 2 d, which basically met the pollution concentration range for efficient microbial treatment. Comparing Examples 5 to 6 with Examples 1 to 2, for sandy soil sites, when achieving similar pollutant treatment effects, the aeration time required in Steps S1 to S3 was shorter than that for silty clay sites.

[0123] The pollutant concentration at 9d in Example 5 increased slightly compared to that at 4d, but still remained at a level below 100 mg / L. The pollutant concentration at 9d in Example 6 decreased slightly compared to that at 4d and remained at a level below 750 mg / kg.

[0124] 2. Inhibition of in-situ microorganisms As can be seen from Table 9-1 and Table 9-2, the in-situ microbial biomass was relatively high at 0d; at 1d, the microbial biomass at 1m and 5m both decreased, with a greater decrease at 1m, and the antibacterial effect was obvious; at 2d, the microbial biomass at 1m and 5m further decreased. Subsequently (at 6d), the microbial biomass in the groundwater of Example 5 was basically stable at the level of 2×10 5 CFU / ml, and the microbial biomass in the contaminated soil of Example 6 was basically stable at the level of 8×10 7 CFU / g.

[0125] It can be seen that the inhibition effect of ozone micro-nano aeration on in-situ microorganisms is excellent. Basically, after a period of time (at 6d) after completing step S2, the microbial biomass in groundwater can be controlled below the level of 3×10 5 CFU / ml, and the microbial biomass in soil can be controlled below the level of 10×10 7 CFU / g. Comparing Examples 5-6 with Examples 1-2, for sandy soil sites, when achieving a similar microbial biomass control effect, the aeration time required in steps S1 to S3 is shorter than that for silty clay sites.

[0126] The microbial biomass at 9d in Example 5 increased slightly compared to that at 6d, but still remained at a level below 3×10 5 CFU / ml, and the microbial biomass at 9d in Example 6 increased slightly compared to that at 6d and remained at a level below 15×10 7 CFU / g.

[0127] 3. Residual time of ozone From the changing trend of ORP values in Table 11, it can be seen that the in-situ environment was slightly oxidized at 0d; at 1d, the oxidizing property at 1m and 5m both increased, with a greater increase at 1m; at 2d, the oxidizing property at 1m and 5m further increased to the same level, up to 884 mV at most; then it gradually decreased, and at 6d, the oxidizing property dropped back to the level of 200 mV.

[0128] The degree of oxidation of pollutants by ozone micro-nano bubble aeration is intense in a short period of time after aeration (at 2 days), but the duration is not long. It can be considered that there is only a very small amount of ozone residue at 9 days. This is mainly because of the designed use of ozone micro-nano bubble aeration in steps S1 and S2, which is to avoid the adverse effects of ozone micro-nano bubbles on the subsequent process (the addition of exogenous composite microbial agents). Correspondingly, it is manifested that the oxidizing property (ORP value) in the environment drops to a certain level at a controllable time node.

[0129] Comparing Examples 1 to 2, it can be obtained that the ozone residue time in Examples 5 to 6 is shorter and the ORP decline rate is faster. This is because the sand permeability in Examples 5 to 6 is better, and the remaining ozone concentration is more easily diluted by the air / oxygen micro-nano bubble water in step S3. Therefore, it is determined that the ORP value for judging the ozone residue amount can be higher. This means that it can be considered that the pretreatment is completed 2 to 4 days after the completion of step S2 in Examples 5 to 6, and step S3 (air / oxygen micro-nano aeration stage) can be entered. This is due to the soil properties in Examples 5 to 6, which optimize this process effect and reduce the time.

[0130] The above examples are only to illustrate the technical concept and characteristics of the present invention. The purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. An in-situ remediation or control method for contaminated soil and groundwater by combining ozone aeration and microorganisms, characterized in that, It includes the following steps: S1 Inject ozone micro-nano bubbles with the first particle size into the soil or groundwater, and conduct continuous aeration for 1 to 5 days, with the aeration time of 6 to 10 hours per day. The first particle size is at the nano level; S2 Inject ozone micro-nano bubbles with the second particle size into the soil or groundwater, and conduct continuous aeration for 1 to 5 days, with the aeration time of 6 to 10 hours per day. The second particle size is larger than the first particle size, and the second particle size is at the micron level; S3 After 2 to 9 days of completion of step S2, inject air micro-nano bubbles or oxygen micro-nano bubbles with the third particle size into the soil or groundwater, and conduct continuous aeration for 1 to 4 days, with the aeration time of 6 to 10 hours per day. The third particle size is at the nano level; S4 Inject a composite microbial inoculum 12 to 24 hours after the completion of step S3.

2. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microbial complex according to claim 1, characterized in that: The range of the first particle size is 90 to 120 nm, and / or the range of the second particle size is 8 to 12 μm.

3. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism compounding according to claim 1, characterized in that: The microbial strains in the composite microbial inoculum are all aerobic bacteria.

4. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism complex according to claim 3, characterized in that: The viable cell count concentration of the compound microbial inoculum is not less than 1×10 9 CFU / mL.

5. The in-situ remediation or control method for contaminated soil and groundwater by combining ozone aeration and microorganisms according to claim 1, characterized in that : The micro-nano bubbles and the composite microbial inoculum are injected through the same point; or, the injection point of the composite microbial inoculum is downstream of the injection point of the micro-nano bubbles, and the distance from the injection point of the micro-nano bubbles is less than or equal to 1 m.

6. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism complex according to claim 1, characterized in that: The pollutants in the contaminated soil or groundwater are one or more of chlorinated hydrocarbons, benzene series, polychlorinated biphenyls, organic pesticides, and phenols.

7. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism complex according to claim 1, characterized in that: 60 to 135 days after step S4, the pollutant content in the groundwater is 0.4 to 2000 μg / L.

8. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism compound according to claim 1, characterized in that: 45 to 135 days after step S4, the pollutant content in the soil is less than 560 mg / kg.

9. The in-situ remediation or control method for contaminated soil and groundwater by combining ozone aeration and microorganisms according to claim 1, characterized in that: Taking every 5 m depth of the soil or groundwater as a unit, in step S1, the ozone micro-nano bubbles with the first particle size are injected into each unit at a depth of 4 to 6 m, and / or in step S2, the ozone micro-nano bubbles with the second particle size are injected into each unit at a depth of 4 to 6 m, and / or in step S3, the air micro-nano bubbles or oxygen micro-nano bubbles with the third particle size are injected into each unit at a depth of 4 to 6 m.

10. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism compounding according to claim 1, characterized in that: When the object to be repaired is the groundwater, 0 to 24 hours after the completion of step S3, the pollutant concentration is less than 200 mg / L.

11. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism compounding according to claim 1, characterized in that: When the object to be repaired is the groundwater, within 0 to 24 hours after step S3 is completed, the microbial biomass is less than 2×10 6 CFU / ml.

12. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microbial compound according to claim 1, characterized in that: When the object to be repaired is the groundwater, 0 to 24 hours after the completion of step S3, the redox potential is less than 300 mV.

13. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism combination according to claim 1, characterized in that: When the object to be repaired is the soil, 0 to 24 hours after the completion of step S3, the concentration of recalcitrant pollutants is less than 1000 mg / kg.

14. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism complex according to claim 1, characterized in that: When the object to be repaired is the soil, within 0 to 24 hours after step S3 is completed, the microbial biomass is less than 1.5×10 8 CFU / g.

15. The in-situ remediation or control method of contaminated soil and groundwater by ozone aeration and microorganism compound according to claim 1, characterized in that: The soil environment is one or more of silt, clay, silty clay, silty sand, or sandy soil.

16. An in-situ remediation or control method for contaminated soil and groundwater by combining ozone aeration and microorganisms, characterized in that, It includes the following steps: S1 Inject ozone micro-nano bubbles with the first particle size into the soil or groundwater, and conduct continuous aeration for 1 to 5 days, with the aeration time of 6 to 10 hours per day. The first particle size is at the nano level; S2 Inject ozone micro-nano bubbles with the second particle size into the soil or groundwater, and conduct continuous aeration for 1 to 5 days, with the aeration time of 6 to 10 hours per day. The second particle size is larger than the first particle size, and the second particle size is at the micron level; S3 Inject a composite microbial inoculum 12 to 24 hours after the completion of step S2.

17. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism complex according to claim 16, characterized in that: The first particle size range is 90 to 120 nm, and / or the second particle size range is 8 to 12 μm.

18. The in-situ remediation or control method for contaminated soil and groundwater by ozone aeration and microorganism compounding according to claim 16, characterized in that: The composite microbial inoculum is an aerobic bacterium, and / or an anaerobic bacterium.

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