A low-permeability contaminated stratum fracturing and biodegradation remediation system and method

Abstract

The application provides a low-permeability contaminated stratum fracturing and biodegradation remediation system and method, and the remediation system comprises a casing, a hydraulic fracturing device, a biological agent injection device, a cross resistivity monitoring device, a pH driving device, a thermal resistance driving device and an online monitoring and control system, wherein the hydraulic fracturing device is used for manufacturing cracks in the soil to provide a channel for biological agent delivery; the biological agent injection device is used for delivering the biological agent to the contaminated soil through the cracks; the cross resistivity monitoring device is used for monitoring resistivity changes in real time to adjust the injection amount and injection process of the biological agent; the pH driving device and the thermal resistance driving device are used for changing the soil pH and temperature, respectively; and the online monitoring and control system is connected with the above five devices to monitor and control the operation of the whole remediation system. The application has the advantages of simple process, environmental friendliness, low cost, good remediation effect, accurate and rapid remediation and large-scale remediation.

Description

Technical Field

[0001] This invention belongs to the field of soil and groundwater pollution remediation technology, specifically relating to a biodegradation remediation method for low-permeability sites, and more particularly to an environmentally driven fracturing enhancement and biodegradation online monitoring and regulation remediation technology. Background Technology

[0002] Currently, in-situ remediation methods mainly include chemical oxidation, multiphase extraction, and biodegradation remediation. Chemical oxidation involves injecting chemicals to react with organic pollutants, achieving pollutant degradation. However, the large-scale use of chemicals can easily cause secondary soil pollution. Multiphase extraction involves extracting groundwater carrying pollutants and removing them through elution and adsorption. This technology suffers from drawbacks such as complex processing, slow remediation speed, high cost, and poor remediation effect. Biodegradation remediation degrades organic pollutants into inorganic and harmless substances, offering advantages such as low cost, simple remediation process, and no secondary pollution, and is increasingly being widely applied to various contaminated sites. However, contaminated sites in coastal cities often exhibit low permeability. The strong compaction of low-permeability clay severely hinders the large-scale injection of remediation agents, forcing them to rely on the infiltration capacity of microbial communities to migrate to deeper contaminated areas. However, the limited migration speed of these microbial communities results in insufficient contact between the remediation agents and the contaminated soil, leading to problems such as small remediation area and poor remediation effect.

[0003] Current biodegradation remediation technologies face two main challenges: First, the concealed and complex underground structures in low-permeability contaminated sites make it difficult to effectively regulate and control the bioremediation process. It's challenging to control the injection rate and volume of biopharmaceuticals, hindering real-time monitoring of degradation effects and adjustments to the remediation process based on these results. Furthermore, microorganisms are highly dependent on their environment, and the variability of the underground environment limits their activity, necessitating environmental-driven methods to enhance microbial activity and accelerate pollutant decomposition. Second, while traditional resistivity monitoring methods are readily applicable to surface monitoring, allowing for stable and reliable results, monitoring resistivity changes in deeper underground areas requires electrodes in monitoring wells for cross-well measurements to meet depth requirements. Installing electrodes in confined wells presents a significant challenge, making insertion and removal difficult. Insufficient insertion can lead to poor contact between the electrode and soil, severely impacting remediation monitoring. Furthermore, electrodes are difficult to remove and reuse, increasing remediation costs and wasting resources. Therefore, solutions are urgently needed for electrode insertion and the recycling of monitoring devices in remediation monitoring systems. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a fracturing-enhanced biodegradation remediation system and method for low-permeability contaminated formations. By using a cross-resistivity monitoring device to dynamically regulate the injection of biological agents and the remediation process under environmental driving forces, and further, by employing an electrode extension device and a reaction force tensioning device to achieve the reuse of important components of the remediation system, the goal of green, economical, and efficient remediation is achieved.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] Technical Solution 1:

[0007] A fracturing-enhanced biodegradation remediation system for low-permeability contaminated formations includes a casing 1, a hydraulic fracturing device, a biochemical injection device, a cross-resistivity monitoring device, a pH driving device, a thermal resistance driving device, and an online monitoring and control system 13, wherein:

[0008] The casing 1 is installed in the soil of the contaminated site to prevent the soil near the borehole from collapsing. The casing 1 has several holes for use as injection channels for fracturing fluid, biological agents and pH solution.

[0009] The hydraulic fracturing device is used to create fractures in the soil to provide channels for the delivery of biological agents;

[0010] The biological agent injection device is used to deliver biological agents through cracks to the contaminated soil.

[0011] The cross resistivity monitoring device is used to monitor resistivity changes in real time in order to adjust the injection amount and injection process of the biological agent;

[0012] The pH driving device is used to change the soil pH, and the thermal resistance driving device is used to adjust the soil temperature. The pH driving device and the thermal resistance driving device are used to improve the activity and reproduction rate of microorganisms and accelerate the decomposition of organic pollutants by microorganisms.

[0013] The online monitoring and control system 13 is connected to the hydraulic fracturing device, the biological agent injection device, the cross resistivity monitoring device, the pH driving device, and the thermal resistance driving device to monitor and control the operation of the entire repair system online.

[0014] Technical Solution Two:

[0015] A fracturing-enhanced biodegradation remediation system for low-permeability contaminated formations includes a casing 1, a hydraulic fracturing device, a biochemical injection device, a cross-resistivity monitoring device, a pH driving device, a thermal resistance driving device, and an online monitoring and control system 13. It also includes a well casing 2, an electrode extension device 4, and a reaction force tensioning device 5, wherein:

[0016] The casing 1 is installed in the soil of the contaminated site to prevent the soil near the borehole from collapsing. The casing 1 has several holes for use as injection channels for fracturing fluid, biological agents and pH solution.

[0017] The hydraulic fracturing device is used to create fractures in the soil to provide channels for the delivery of biological agents;

[0018] The biological agent injection device is used to deliver biological agents through cracks to the contaminated soil.

[0019] The cross resistivity monitoring device is used to monitor resistivity changes in real time in order to adjust the injection amount and injection process of the biological agent;

[0020] The pH driving device is used to change the soil pH, and the thermal resistance driving device is used to adjust the soil temperature. The pH driving device and the thermal resistance driving device are used to improve the activity and reproduction rate of microorganisms and accelerate the decomposition of organic pollutants by microorganisms.

[0021] The online monitoring and control system 13 is connected to the hydraulic fracturing device, the biological agent injection device, the cross resistivity monitoring device, the pH driving device, and the thermal resistance driving device to monitor and control the operation of the entire repair system online.

[0022] The well pipe 2, electrode telescopic device 4, and reaction force tensioning device 5 are used to lower the electrodes of the cross resistivity monitoring device to a suitable position in the underground well, so as to realize the insertion and extraction of the electrodes in the soil.

[0023] Technical Solution 3:

[0024] A method for fracturing-enhanced biodegradation remediation of low-permeability contaminated formations, based on the remediation system of either Technical Solution 1 or Technical Solution 2, includes the following steps:

[0025] Step 1: Drilling and constructing a well;

[0026] Step 2: Install and repair the main system components;

[0027] Step 3: Perform hydraulic fracturing using a hydraulic fracturing device;

[0028] Ensure that the fracturing fluid injection pipe 802 is connected to the fracturing nozzle 101. Turn on the hydraulic fracturing injection pump 801 of the hydraulic fracturing device through the online monitoring and control system 13. High-pressure water is injected into the fracturing nozzle 101 to perform hydraulic fracturing. A fracture 3 is formed near the fracturing nozzle 101. Propionate is delivered into the fracture to form an agent injection channel to prevent the fracture from closing.

[0029] Step 4: Use a cross-resistivity monitoring device to monitor the resistivity across the orifice;

[0030] All electrodes 703 in the two underground wells are connected to the electrode line interface 702 of the cross resistivity monitoring device, and the mobile power supply 704 is connected to the resistivity monitoring system 701. According to the online monitoring and control system 13, any two electrodes in the two underground wells are controlled to provide current, and the voltage of the remaining two electrodes is tested. The resistivity of the area between the two underground wells is calculated according to the resistivity testing principle. Monitoring is performed once at fixed intervals and continuous online monitoring is performed.

[0031] Step 5: Utilize a biological agent infusion device to inject the repair agent;

[0032] Prepare a mixture of microbial agent and growth promoter, ensure that the biopharmaceutical injection tube 602 is connected to the biopharmaceutical injection hole 102, open the biopharmaceutical injection pump 601 using the online monitoring and control system 13, and inject the microbial repair agent into the crack 3 along the biopharmaceutical injection tube 602. Monitor the resistivity based on the relationship between the amount of microbial injection and the change in resistivity, and use the online monitoring and control system 13 to regulate the amount of microbial injection and the injection speed.

[0033] Step Six: Utilize a pH-driven device and a thermal resistance-driven device to achieve pH and temperature environment-driven operation;

[0034] Based on the resistivity monitoring results fed back by the online monitoring and control system 13, the rate of pollutant decomposition and the remediation area are obtained. The online monitoring and control system 13 controls the temperature sensor 1003 of the thermal resistance drive device and the pH sensor 903 of the pH drive device to test the ambient temperature and pH at the crack 3, respectively. According to the suitable pH and temperature for microbial survival, the online monitoring and control system 13 turns on the thermal resistance drive device and the pH drive device to adjust the soil temperature and pH, enhance microbial activity, accelerate the decomposition of organic pollutants by microorganisms, improve remediation efficiency and expand the remediation range.

[0035] Step 7: Integrated and collaborative work of resistivity monitoring, bioremediation, and environmentally driven processes;

[0036] Step 8: Recycling and Repair System;

[0037] Step 9: Reinstall the remediation system in the next borehole to carry out bioremediation.

[0038] By adopting the above solution, the beneficial effects of the present invention are:

[0039] The low-permeability contaminated formation fracturing enhanced biodegradation remediation system of the present invention has the advantages of simple structure, low cost, strong controllability, wide remediation range and precise remediation.

[0040] To address the challenges of low permeability in contaminated formations, difficulties in effectively injecting and controlling remediation agents, and high remediation efficiency and cost, this invention proposes an integrated control system encompassing fracturing enhancement, biodegradation remediation, environmentally driven processes, and real-time remediation monitoring. This system utilizes resistivity information from a cross-resistivity monitoring device to guide the biopharmaceutical injection device, and correlates the amount of microorganisms injected (M) with changes in resistivity. The precise control of the relationship between the injection volume and injection speed effectively avoids problems such as insufficient or excessive injection, greatly saving repair costs;

[0041] The soil environment is altered by employing a dual environmental driving device that combines pH-driven and thermal resistance-driven mechanisms. Temperature and pH sensors are used to test the soil temperature and pH in the contaminated area. Microorganisms exhibit good degradation ability and activity within a temperature range of 20-35℃ and a pH range of 6-8. By adjusting the environmental conditions of the microorganisms through the pH-driven and thermal resistance-driven mechanisms, the activity of the microorganisms is enhanced, and the decomposition of pollutants by the microorganisms is accelerated in a larger contaminated area, effectively improving the injection effect and remediation efficiency.

[0042] Furthermore, the cross-resistivity monitoring device employs an electrode extension and reaction tension device, enabling the electrode to be inserted deeper into contaminated soil within confined underground wells (also known as underground boreholes). This ensures good contact between the electrode and the soil, forming a stable electric field, resulting in more stable and reliable resistivity measurements. This facilitates accurate monitoring and precise control of the microbial remediation process. In addition, the electrode extension and reaction tension device allows for the recycling of the cross-resistivity monitoring device. After remediation, the electrode and well casing can be removed, and the recovered device can be placed in the next underground well for continued remediation monitoring, saving significant remediation costs and effectively solving the challenges of inserting and recycling electrodes within confined underground wells. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the structure and scenario of a low-permeability contaminated formation fracturing-enhanced biodegradation remediation system as described in Example 1.

[0044] Figure 2 This is a schematic diagram of the cross resistivity monitoring device in Example 1.

[0045] Figure 3 This is a schematic diagram of the pH driving device and the thermal resistance driving device in Example 1.

[0046] Figure 4 This is a schematic diagram of the online monitoring and control system structure in Example 1.

[0047] Figure 5 This is a schematic diagram of the workflow of the online monitoring and control system in Example 1.

[0048] Figure 6 This is a schematic diagram showing the relationship between pollutant concentration and resistivity in Example 1.

[0049] Figure 7 This is a schematic diagram of the structure and scenario of a low-permeability contaminated formation fracturing enhanced biodegradation remediation system as described in Example 2.

[0050] Figure 8 This is a schematic diagram of the electrode telescopic device and the reaction force tensioning device in Example 2.

[0051] Figure label:

[0052] 1-Casing; 101-Fracturing nozzle; 102-Biological agent injection nozzle; 103-pH injection nozzle;

[0053] 2-Well casing; 201-Electrical limit position hole;

[0054] 3-Cracks;

[0055] 4-Electrode telescopic device; 401-Roller; 402-Compression plate; 403-Sliding wheel; 404-Sliding plate; 405-Electrode spring;

[0056] 5-Reaction tensioning device; 501-Jack; 502-Fixing plate; 503-Support rod; 504-Telescopic connecting rod; 505-Connecting piece;

[0057] 601-Biological agent injection pump; 602-Biological agent injection tubing; 603-Intelligent flow control valve;

[0058] 701-Resistivity monitoring and controller; 702-Electrode wire interface; 703-Electrode; 704-Power bank; 705-Current field; 706-Electrode wire;

[0059] 801 - Hydraulic fracturing injection pump; 802 - Fracturing fluid injection pipe; 803 - Fracturing fluid injection valve;

[0060] 901 - pH injection pump; 902 - pH controller; 903 - pH sensor; 904 - pH injection tubing; 905 - pH injection valve;

[0061] 1001 - Temperature controller; 1002 - Variable temperature resistor; 1003 - Temperature sensor; 1004 - Resistance regulating valve;

[0062] 11-Contaminated soil;

[0063] 12-Cable;

[0064] 13-Online monitoring and control system. Detailed Implementation

[0065] The technical solutions provided in this application will be further described below with reference to specific embodiments and accompanying drawings. The advantages and features of this application will become clearer from the following description.

[0066] Example 1:

[0067] like Figures 1-5 As shown, a fracturing-enhanced biodegradation remediation system for low-permeability contaminated formations includes a casing 1, a hydraulic fracturing device, a biochemical injection device, a cross-resistivity monitoring device, a pH driving device, a thermal resistance driving device, and an online monitoring and control system 13. Wherein:

[0068] The casing 1 is installed in the soil of the contaminated site to prevent the soil near the borehole from collapsing. The casing 1 has several holes for use as injection channels for fracturing fluid, biological agents, pH solution, etc.

[0069] The hydraulic fracturing device is used to create cracks 3 in the soil to provide a channel for the delivery of biological agents;

[0070] The biological agent injection device is used to deliver the biological agent through crack 3 to the contaminated soil.

[0071] The cross resistivity monitoring device is used to monitor resistivity changes in real time in order to adjust the injection amount and injection process of the biological agent;

[0072] The pH driving device is used to change the soil pH, and the thermal resistance driving device is used to adjust the soil temperature. The pH driving device and the thermal resistance driving device are used to improve the activity and reproduction rate of microorganisms and accelerate the decomposition of organic pollutants by microorganisms.

[0073] The online monitoring and control system 13 is connected to the hydraulic fracturing device, the biological agent injection device, the cross resistivity monitoring device, the pH driving device, and the thermal resistance driving device to monitor and control the operation of the entire repair system online.

[0074] In application, a borehole is drilled at the contaminated site, and a casing 1 is inserted to prevent borehole collapse. The hydraulic fracturing device, bioremediation agent injection device, pH driving device, and thermal resistance driving device are connected to the casing 1, which is then lowered into the borehole at the contaminated site and connected to the online monitoring and control system 13, completing the system equipment installation. The online monitoring and control system 13 activates the hydraulic fracturing device and injects high-pressure water and proppant into the contaminated soil to form a fracture 3. Then, the bioremediation agent is injected into the fracture 3 through the bioremediation agent injection device. A cross-resistivity monitoring device is used to monitor the process of microbial decomposition of pollutants in real time. The online monitoring and control system 13 precisely controls the injection volume of bioremediation agent based on the resistivity change information fed back by the cross-resistivity monitoring device, and calls the pH driving device and thermal resistance driving device to adjust the microbial living environment, improve microbial activity, and accelerate the decomposition of pollutants.

[0075] Furthermore, the casing 1 includes fracturing nozzle 101, biological agent injection nozzle 102, and pH injection nozzle 103, as well as mounting holes for installing temperature sensor 1004, pH sensor 903, variable temperature resistor 1002, and electrode 703. In implementation, the number of each hole can be set as needed.

[0076] Furthermore, the hydraulic fracturing device, such as Figure 1 , Figure 4 As shown, the system includes a hydraulic fracturing injection pump 801, a fracturing fluid injection pipe 802, and a fracturing fluid injection valve 803. The hydraulic fracturing injection pump 801 is connected to the fracturing fluid injection pipe 802, and the fracturing fluid injection valve 803 is installed on the fracturing fluid injection pipe 802. The hydraulic fracturing injection pump 801 is connected to an online monitoring and control system 13 via a cable 12, and the hydraulic fracturing process is controlled by the online monitoring and control system 13.

[0077] Because the high density of low-permeability clay severely hinders the injection of remediation agents, a hydraulic fracturing device is used to create cracks 3 as agent delivery channels. During implementation, the fracturing fluid injection pipe 802 is connected to the fracturing nozzle 101 of the casing 1, forming a fracturing fluid injection channel. After opening the fracturing fluid injection valve 803, high-pressure water is injected at the fracturing nozzle 101 through the fracturing injection pump 801 to form cracks 3 with proppant. Cracks 3 serve as the biological agent injection channel for the biological agent injection device. The proppant prevents the cracks from compacting and closing under the weight of the soil. The hydraulic fracturing device solves the problem of agent injection due to the lack of remediation agent delivery channels caused by the low porosity of low-permeability contaminated sites.

[0078] Furthermore, such as Figure 1 , Figure 4 As shown, the biological agent injection device includes a biological agent injection pump 601, a biological agent injection pipe 602, and an intelligent flow control valve 603. The biological agent injection pump 601 is connected to the biological agent injection pipe 602, and the intelligent flow control valve 603 is installed on the biological agent injection pipe 602. The biological agent injection pump 601 is connected to an online monitoring and control system 13 via a cable 12, and the online monitoring and control system 13 controls the agent injection process.

[0079] Preferably, as an embodiment, the biopharmaceutical injection holes 102 can be located below the fracturing nozzles 101 and near the fractures 3, so that the remediation agent can be transported to the contaminated area along the fractures 3 formed by fracturing. When using a hydraulic fracturing device for fracturing, the biopharmaceutical injection device is shut off; when using a biopharmaceutical injection device for biopharmaceutical injection, the hydraulic fracturing device is shut off. In practice, the biopharmaceutical injection pipe 602 is connected to the biopharmaceutical injection hole 102 of the casing 1 to form a biopharmaceutical injection channel; the biopharmaceutical injection pump 601 transports the biopharmaceutical through the biopharmaceutical injection pipe 602 to the biopharmaceutical injection hole 102 and flows through the fractures 3 to the contaminated soil. The microorganisms in the biopharmaceutical decompose the organic matter in the contaminated soil, breaking down organic pollutants into inorganic and harmless substances, thereby achieving the purpose of removing pollutants and remediating the soil.

[0080] Furthermore, the cross resistivity monitoring device, such as Figure 2 As shown, the device includes a resistivity monitoring controller 701, an electrode wire interface 702, electrode wires 706, electrodes 703, and a power supply 704. The resistivity monitoring controller 701 is used to test and analyze resistivity data and visualize the resistivity variation range. It has an electrode wire interface 702, and several electrodes 703 are connected to the electrode wire interface 702 via electrode wires 706. The electrodes 703 are in contact with the soil. The power supply 704 is connected to the resistivity monitoring controller 701 via a cable 12 to supply power to the resistivity monitoring controller 701. The resistivity monitoring controller 701 is connected to an online monitoring and control system 13 via the cable 12. The resistivity monitoring controller 701 performs resistivity testing and data analysis, and based on the analysis results, the online monitoring and control system 13 further regulates the biopharmaceutical injection device. Specifically, the number of electrodes 703 can be set as needed.

[0081] The cross-resistivity monitoring device uses power supply electrodes (A and B) to supply power to the ground, while simultaneously observing the potential difference at measuring electrodes (M1, N1, M2, N2, M3, and N3) and calculating the resistivity. In the embodiment, as shown... Figure 2 As shown, the first sleeve has four electrodes on its outer side, namely A, M1, M2, and M3; the second sleeve has four electrodes on its outer side, namely B, N1, N2, and N3. Electrodes A and B serve as power supply electrodes, providing current to form a current field 705. Electrodes M1, M2, and M3 on the outer side of the first sleeve and N1, N2, and N3 on the outer side of the second sleeve serve as measuring electrodes. The resistivity is calculated by measuring the voltage value of any two measuring electrodes. The resistivity monitoring controller 701 automatically powers on at regular intervals, tests the voltage, and calculates the resistivity data changing over time. The resistivity change caused by pollutant degradation in the region between the two sleeves is calculated according to the resistivity formula:

[0082] (1)

[0083] In the formula, ρ For the resistivity of the medium, I The intensity of the current flowing underground, The potential difference between the electrodes. K This is called the geometric device factor, and it is determined based on the relative positions between the electrodes. K The expression is:

[0084] (2)

[0085] In the formula, A and B represent the power supply electrodes, M and N represent the measuring electrodes, and AM, BM, AN, and BN are the distances between the power supply electrodes and the measuring electrodes.

[0086] This invention employs the time-shift resistivity method to monitor the pollutant degradation process. The resistivity monitoring principle is based on the non-linear relationship between resistivity and pollutant concentration. In low-permeability clay contaminated sites, microbial decomposition of pollutants leads to a decrease in pollutant concentration, resulting in a corresponding decrease in resistivity. Therefore, changes in pollutant concentration can be dynamically monitored by observing the change in resistivity over time. The pollutant concentration in low-permeability clay is obtained based on Archie's law. With resistivity Relationship:

[0087] (3)

[0088] In the formula, Porosity For pollutant concentration, The resistivity of the aqueous phase, The total resistivity of all components, The bonding index is the number of cementing components. Let be the resistivity of the soil particles. The parameters for a low-infiltration contamination site are: , , , pollutant concentration With resistivity Relationship such as Figure 6 As shown.

[0089] According to equation (3), the relationship between the change in resistivity and the change in pollutant concentration can be obtained as follows:

[0090] (4)

[0091] In the formula, is a proportionality coefficient, representing the effect of pollutant concentration on resistivity changes.

[0092] The rate at which microorganisms decompose organic pollutants is directly measured through laboratory experiments, thereby obtaining the microbial decomposition rate constant. k The rate at which microorganisms decompose organic pollutants can be expressed as:

[0093] (5)

[0094] Assuming the total amount of microorganisms M is directly proportional to the total amount of pollutants decomposed, the required amount of microorganisms can be expressed as:

[0095] (6)

[0096] In the formula, is a proportionality constant, representing the amount of microorganisms required to decompose a unit of pollutant.

[0097] Combining equations (4) to (6), we can obtain the relationship between the amount of microorganism injected M and the resistivity change. The relationship is as follows:

[0098] (7)

[0099] The online monitoring and control system 13 adjusts the microbial injection volume M based on the change in resistivity. The relationship between them is used for regulation, such as Figure 5 As shown, a resistivity test was performed using a cross-resistivity monitoring device to obtain the initial background resistivity before the biopharmaceutical injection. After the injection begins, resistivity tests are performed at fixed intervals, such as every 10 minutes, to obtain the resistivity change value. Based on the change in resistivity The rate of pollutant decomposition and the remediation area are determined, and the amount of microorganisms injected into the biopharmaceutical injection device is adjusted based on resistivity feedback information. That is, when the resistivity changes rapidly, it indicates that the microbial degradation rate is fast, and the amount of microbial agent injected should be increased. Conversely, when the resistivity changes slowly, the microbial degradation rate of pollutants is slow, and the amount of microorganisms injected should be reduced. By adjusting the amount of microorganisms injected into the biopharmaceutical injection device M based on resistivity feedback information tested by the cross-resistivity monitoring device, the biopharmaceutical injection device can be precisely controlled, effectively avoiding waste caused by insufficient or excessive injection.

[0100] Furthermore, when the agent is delivered to an area without hydraulic fracturing cracks, it is difficult to inject the agent effectively. By using a pH-driven device and a thermal resistance-driven device to adjust the soil environment and improve the activity of microorganisms, the microorganisms are driven to move towards nutrients such as pollutants, which accelerates the further decomposition of organic pollutants by the microorganisms. This remediation system can save a lot of money and time costs and effectively improve remediation efficiency.

[0101] Furthermore, the pH driving device, such as Figure 1 , Figure 3 , Figure 4 As shown, the system includes a pH injection pump 901, a pH controller 902, a pH sensor 903, a pH injection pipe 904, and a pH injection valve 905. The pH sensor 903 is located near the bottom of crack 3. The pH controller 902 and the pH sensor 903 are connected by a cable to form a pH testing system for obtaining the pH value of the test area. The pH controller 902 and the pH injection pump 901 are connected by a cable to control the pH adjustment process. The pH injection pump 901, the pH injection pipe 904, and the pH injection valve 905 are connected to form a pH adjustment system. The pH controller 902 is connected to an online monitoring and control system 13 via a cable 12. The pH controller 902 performs pH testing and analysis, and based on the test results, the online monitoring and control system 13 further regulates the pH controller 902 to control the pH testing and pH adjustment process.

[0102] In practice, the pH injection pipe 904 is connected to the pH injection nozzle 103 of the sleeve 1 to form a pH liquid injection channel. The pH liquid is transported through the pH injection pipe 904 to the pH injection nozzle 103 and delivered to the contaminated soil using the pH injection pump 901. Since the suitable pH range for microorganisms is approximately 6-8, excessively acidic or alkaline environments will inhibit microbial activity. The pH value in the soil is tested by the pH sensor 903 connected to the pH controller 902. The online monitoring and control system 13 adjusts the pH controller 902 based on the tested acidity and alkalinity information. The pH controller 902 then injects pH liquid through the pH injection pump 901 to change the soil pH to approximately 6-8, thereby enhancing microbial activity, accelerating the decomposition of organic pollutants by microorganisms, and speeding up the remediation efficiency.

[0103] In this embodiment, the pH injection nozzle 103 is located between the fracturing nozzle 101 and the biological agent injection nozzle 102 and is located near the crack 3, which facilitates the injection of liquid into the crack 3. The pH sensor 903 is located below the crack 3, and the number of pH sensors 903 can be set as needed.

[0104] Furthermore, the thermal resistor driving device, such as Figure 1 , Figure 4As shown, the system includes a temperature controller 1001, a variable-temperature resistor 1002, a temperature sensor 1003, and a resistance regulating valve 1004. The variable-temperature resistor 1002 and the temperature sensor 1003 are positioned near the top of the crack 3. The temperature controller 1001 is connected to the temperature sensor 1003 via a cable 12 to acquire temperature information. The temperature controller 1001 is also connected to the variable-temperature resistor 1002 via a cable 12, on which the resistance regulating valve 1004 is connected to control the variable-temperature resistor 1002 to change its temperature based on the temperature information. The temperature controller 1001 is connected to an online monitoring and control system 13 via the cable 12, and the online monitoring and control system 13 controls the temperature testing and temperature regulation process.

[0105] Since microorganisms exhibit good degradation capabilities within a temperature range of 20-35℃, the soil temperature in the polluted area is tested by temperature sensor 1003. The online monitoring and control system 13 adjusts the temperature controller 1001 based on the tested temperature information, and changes the soil temperature through variable temperature resistor 1002 to adjust the soil temperature to 20-35℃ as much as possible, thereby increasing the activity and reproduction rate of microorganisms, accelerating the decomposition of organic pollutants by microorganisms, and thus improving the remediation efficiency.

[0106] In this embodiment, the variable temperature resistor 1002 and the temperature sensor 1003 are disposed above the crack 3, and the number of variable temperature resistor 1002 and temperature sensor 1003 can be set as needed.

[0107] Example 2:

[0108] This embodiment is a further improvement on embodiment 1.

[0109] like Figure 7 As shown, a low-permeability contaminated formation fracturing enhanced biodegradation remediation system is provided, which, based on the low-permeability contaminated formation fracturing enhanced biodegradation remediation system of Example 1, adds a well casing 2, an electrode telescopic device 4, and a reaction tensioning device 5, wherein:

[0110] The diameter of the well pipe 2 is smaller than that of the casing 1, and several electrical limit holes 201 are opened in the middle of the side wall of the well pipe 2. The well pipe 2 is embedded in the casing 1.

[0111] There are several electrode telescopic devices 4, which are installed inside the well pipe 2 and connected to the well pipe 2. The electrode telescopic device 4 is connected to the electrode 703, which is installed at the electrical limit hole 201 of the well pipe 2.

[0112] The reaction force tensioning device 5 is connected to the electrode telescopic device 4 and is installed on the ground at the top of the well pipe 2;

[0113] The well pipe 2, electrode telescopic device 4, and reaction force tensioning device 5 are used to lower the electrode 703 to a suitable position in the underground well, so as to realize the insertion and extraction of the electrode 703 in the soil.

[0114] The electrode telescopic device 4, the reaction force tensioning device 5, and the cross resistivity monitoring device work together to insert the electrode 703 into the narrow underground well, thereby achieving better contact between the electrode and the soil and obtaining stable and reliable resistivity monitoring results. This allows for more accurate control of the repair process based on the monitoring results. In addition, the electrode telescopic device 4 and the reaction force tensioning device 5 enable the electrode 703 to be recycled and reused. After the repair is completed, the electrode 703 and the well pipe 2 can be pulled out and placed into the next underground well for continued repair monitoring, saving a lot of repair costs and solving the problem of electrode installation in narrow monitoring wells.

[0115] Furthermore, such as Figure 8 As shown, the reaction tensioning device 5 includes a jack 501, a fixed plate 502, a support rod 503, a telescopic connecting rod 504, and a connector 505. Specifically: the upper and lower fixed plates 502 are fixedly connected to form a support frame via the support rod 503; the jack 501 is positioned between the two fixed plates 502; and the upper end of the telescopic connecting rod 504 is fixedly connected to the jack 501 via the connector 505. The extension and compression of the jack 501 drive the telescopic connecting rod 504 to move up and down.

[0116] In this embodiment, the upper end of the telescopic connecting rod 504 is welded to the jack 501 via a connector 505, and the fixing plate 502 is welded to the support rod 503.

[0117] Furthermore, such as Figure 8As shown, the electrode telescopic device 4 includes a roller 401, a compression plate 402, a sliding wheel 403, a sliding plate 404, and an electrode spring 405. Wherein: Roller 401 is connected to the middle of the telescopic connecting rod 504 of the reaction tension device 5, so that roller 401 and telescopic connecting rod 504 can move simultaneously in the same direction; sliding plate 404 is horizontally arranged below roller 401 and connected to well pipe 2, and sliding plate 404 is provided with groove channel; the compression plate 402 is an inclined structure, and the inclined surface is opposite to roller 401 and located below roller 401. Sliding wheel 403 is provided at the bottom of compression plate 402. Sliding wheel 403 is in the groove channel of sliding plate 404, so that compression plate 402 slides on sliding plate 404 along groove channel through sliding wheel 403 at its bottom. Electrode 703 is fixedly connected to the left end of compression plate 402; electrode 703 is located in well pipe 2, and electrode spring 405 is horizontally arranged outside electrode 703. The two ends of electrode spring 405 are respectively connected to well pipe 2 and compression plate 402. In the initial state before electrode 703 is inserted into the soil, electrode spring 405 is not compressed and remains in a naturally extended state. During the process of electrode 703 being inserted into the soil for resistivity monitoring, electrode spring 405 remains compressed. Under the compression and rebound action of electrode spring 405, the up-and-down movement of roller 401 drives compression plate 402 to move left and right on sliding plate 404, thereby driving the insertion and removal of electrode 703.

[0118] In this embodiment, the roller 401 is welded to the middle of the telescopic connecting rod 504 of the reaction tension device 5.

[0119] Furthermore, the electrical limit hole 201 of the well pipe 2 is provided with a groove for fixing the position of the electrode spring 405.

[0120] In a low-permeability contaminated soil area, a set of underground wells are drilled and casing 1 is lowered. The electrode telescopic device 4 is connected to the well casing 2 as a whole and then lowered into the casing 1. Through the jack 501 of the compression reaction tension device 5, the telescopic connecting rod 504 moves downward under the action of the fixed plate 502 and the support rod 503, thereby driving the roller 401 to roll downward. During the downward rolling process, the roller 401 will squeeze the compression plate 402 to the left. The compression plate 402 moves to the left on the sliding plate 404 through the sliding wheel 403, thereby compressing the electrode spring 405. The electrode 703 follows the movement of the compression plate 402 and is smoothly inserted into the soil from the narrow well, realizing stable contact between the electrode and the soil, and enabling more accurate monitoring of the bioremediation process.

[0121] After the bioremediation monitoring work is completed, the electrode 703 can be recycled using the electrode telescopic device 4 and the reaction tensioning device 5. By extending the jack 501, since the telescopic connecting rod 504 is welded to the jack 501 connector 505, the jack 501 will drive the telescopic connecting rod 504 to move upward. When the telescopic connecting rod 504 moves upward, it rolls upward along with the roller 401. The compression plate 402 will slide to the right under the rebound action of the electrode spring 405. Since the electrode 703 is welded to the compression plate 402, when the compression plate 402 slides to the right, it pulls the electrode 703 out of the soil. The electrode 703 rebounds into the well pipe 2. Finally, the well pipe 2 and the electrode telescopic device 4 are pulled out of the casing 1 together, which is convenient for reinstallation and reuse in the next contaminated area, saving a lot of remediation costs and effectively solving the limitation that the electrode 703 can only be used once.

[0122] Example 3:

[0123] A method for fracturing-enhanced biodegradation remediation of low-permeability contaminated formations, implemented based on the remediation system described in the above embodiments, includes the following steps:

[0124] Step 1: Drilling and constructing a well.

[0125] A drilling rig was used to drill several underground wells with a diameter of 200mm in the contaminated site, with a spacing of 5 to 10m between adjacent wells.

[0126] Step 2: Repair the installation of major system components.

[0127] The fracturing fluid injection pipe 802 of the hydraulic fracturing device passes through the inner wall of the casing 1 and is connected to the fracturing nozzle 101 by bolts to form a fracturing fluid injection channel, and the hydraulic fracturing injection pump 801 is connected to the online monitoring and control system 13 by cable 12;

[0128] The biological agent injection tube 602 of the biological agent injection device passes through the inner wall of the sleeve 1 and is connected to the biological agent injection hole 102 by bolts to form a drug injection channel, and the biological agent injection pump 601 is connected to the online monitoring and control system 13 by cable 12;

[0129] The pH injection pipe 904 of the pH drive device is passed through the inner wall of the sleeve 1 and connected to the pH injection nozzle 103 by bolts to form a pH liquid injection channel. The pH controller 902 is connected to the pH injection pump 901 and the online monitoring and control system 13 by cable 12. The pH sensor 903 is welded to the sleeve 1 and connected to the pH controller 902 by cable 12.

[0130] The temperature sensor 1003 and the variable temperature resistor 1002 of the thermal resistance drive device are welded onto the sleeve 1 and connected to the temperature controller 1001 through the cable 12 respectively. The temperature controller 1001 is then connected to the online monitoring and control system 13 through the cable 12.

[0131] The resistivity monitoring controller 701 of the cross resistivity monitoring device is connected to the online monitoring and control system 13 via cable 12. Several electrodes 703 are connected to the electrode line interface 702 via electrode line 706. The mobile power supply 704 is connected to the resistivity monitoring controller 701 via cable 12. The electrodes 703 are inserted into the soil.

[0132] Insert casing 1 into the underground well to prevent the hole from collapsing. After the well is completed, let it stand for a period of time to allow the soil to stabilize.

[0133] At this point, the system installation is complete.

[0134] Furthermore, in the remediation system of Example 2, the electrode 703 is inserted into the soil through the electrode hole on the casing 1 via the electrical limit hole 201 of the well pipe 2, specifically as follows:

[0135] Connecting the electrode telescopic device to the well pipe 2 includes: welding the sliding plate 404 to the well pipe 2, installing the sliding wheel 403 at the bottom of the compression plate 402, welding the compression plate 402 to the electrode 703 and placing the sliding wheel 403 in the groove channel of the sliding plate 404, placing the electrode spring 405 into the groove of the electric limit hole 201, the electrode 703 passing through the electrode spring 405 and aligning with the electric limit hole 201, and welding the roller 401 to the middle of the telescopic connecting rod 504 of the reaction force tensioning device 5;

[0136] Insert the well casing 2 together with the electrode telescopic device 4 into the casing 1, and align the electrical limit hole 201 of the well casing 2 with the electrode hole on the casing 1.

[0137] The reaction tensioning device 5 is placed on the ground at the top of the well pipe 2. The telescopic connecting rod 504 of the reaction tensioning device 5 is placed inside the well pipe 2. The jack 501 of the reaction tensioning device 5 is turned on to compress it. The telescopic connecting rod 504 moves downward and drives the compression plate 402 to move to the left, inserting the electrode 703 into the soil to make the electrode contact with the soil more stable.

[0138] Step 3: Perform hydraulic fracturing using a hydraulic fracturing device.

[0139] Ensure that the fracturing fluid injection pipe 802 is connected to the fracturing nozzle 101. Turn on the hydraulic fracturing injection pump 801 of the hydraulic fracturing device through the online monitoring and control system 13. High-pressure water is injected into the fracturing nozzle 101 to perform hydraulic fracturing, forming a fracture 3 near the fracturing nozzle 101. High-permeability fine sand proppant is transported into the fracture to form a proppant injection channel. The proppant injection pressure is about 600 kPa to prevent the fracture from closing.

[0140] Step 4: Use a cross-resistivity monitoring device to monitor the resistivity across the orifice.

[0141] All electrodes 703 in the two underground wells are connected to the electrode line interface 702 of the cross resistivity monitoring device, and the mobile power supply 704 is connected to the resistivity monitoring system 701. According to the online monitoring and control system 13, any two electrodes in the two underground wells are controlled to provide current, and the voltage of the remaining two electrodes is tested. The resistivity of the area between the two underground wells is calculated according to the resistivity testing principle. Monitoring is performed once every 10 minutes for continuous online monitoring.

[0142] Step 5: Inject the repair agent using a biological agent injection device.

[0143] Prepare a mixture of microbial inoculant and growth promoter, ensuring that the biopharmaceutical injection tube 602 is connected to the biopharmaceutical injection port 102. Use the online monitoring and control system 13 to turn on the biopharmaceutical injection pump 601 and inject the microbial repair agent into the crack 3 along the biopharmaceutical injection tube 602. Monitor the resistivity based on the relationship between the amount of microbial injection and the change in resistivity. Use the online monitoring and control system 13 to regulate the amount and speed of microbial injection, and ensure that the injection pressure does not exceed 5 MPa to avoid affecting the growth of microorganisms.

[0144] Step 6: Use a pH driving device and a thermal resistance driving device to achieve pH and temperature environment driving.

[0145] Based on the resistivity monitoring results fed back by the online monitoring and control system 13, the rate of pollutant decomposition and the remediation area are obtained. The online monitoring and control system 13 controls the temperature sensor 1003 of the thermal resistance drive device and the pH sensor 903 of the pH drive device to test the ambient temperature and pH at the crack 3, respectively. According to the suitable pH and temperature for microbial survival, the online monitoring and control system 13 turns on the thermal resistance drive device and the pH drive device to adjust the soil temperature and pH to 20-35℃ and 6-8, respectively, to enhance microbial activity, accelerate the decomposition of organic pollutants by microorganisms, improve remediation efficiency and expand the remediation range.

[0146] Step 7: Integrated and collaborative work of resistivity monitoring, bioremediation, and environmentally driven processes.

[0147] The resistivity monitoring was continued using the operation method in step four. Based on the pollution remediation status feedback from the resistivity monitoring results, the amount of agent injected was precisely controlled. The pH-driven device and the thermal resistance-driven device were used to achieve pH and temperature environment driving, which enhanced microbial activity, increased the migration speed of the remediation agent and expanded the remediation range. This effectively avoided problems such as insufficient or excessive agent injection and greatly improved the remediation efficiency.

[0148] Step 8: Recycling and repairing the system, including important components such as electrode 703, variable temperature resistor 1002, temperature sensor 1003, pH sensor 903, and sleeve 1.

[0149] Furthermore, in the remediation system of Example 2, the electrode 703 is recycled through the electrode telescopic device 4 and the reaction force tensioning device 5. Specifically, the jack 501 of the reaction force tensioning device 5 is activated for tensioning. The telescopic connecting rod 504 moves upward along with the extension of the jack 501. When the telescopic connecting rod 504 moves upward, it rolls upward along with the roller 401. The compression plate 402 slides to the right under the rebound action of the electrode spring 405, pulling the electrode 703 out of the soil and causing the electrode 703 to rebound into the well pipe 2. Then, the well pipe 2 and the electrode telescopic device 4 are pulled out of the casing 1 together. Finally, the casing 1 and the temperature-changing resistor 1002, temperature sensor 1003, and pH sensor 903 connected to it are pulled out of the underground well together, which is convenient for reinstallation and reuse in the next contaminated area. The remediation cost is significantly reduced through reuse.

[0150] Step 9: Reinstall the remediation system in the next borehole to carry out bioremediation.

[0151] The recovered components of the remediation system are reinstalled in other underground wells at the contaminated site. Steps two through eight are repeated to sequentially carry out bioremediation of pollutants in different underground wells using the remediation system until the remediation of all contaminated areas within the site is completed.

[0152] The above description is merely a description of preferred embodiments of this application and is not intended to limit the scope of this application in any way. Any changes or modifications made by those skilled in the art based on the above-disclosed technical content should be considered as equivalent and valid embodiments and fall within the scope of protection of the technical solution of this application.

Claims

1. A low permeability contaminated subterranean formation fracture-stimulating biodegradation remediation system characterized by, The system comprises a casing (1), a hydraulic fracturing device, a biological agent injection device, a cross-resistivity monitoring device, a pH driving device, a thermal resistance driving device, and an online monitoring and control system (13), wherein: The casing (1) is arranged in the contaminated site soil to prevent soil collapse near the borehole, and a plurality of holes are formed in the casing to serve as injection channels for fracturing fluid, biological agents, and pH fluid. The hydraulic fracturing device is used to create cracks in the soil to provide a channel for the delivery of biological agents. The biological agent injection device is used to deliver biological agents to the contaminated soil through the cracks. The cross-resistivity monitoring device is used to monitor resistivity changes in real time to adjust the injection amount and process of biological agents. The pH driving device is used to change the soil's pH, and the thermal resistance driving device is used to adjust the soil temperature, thereby increasing microbial activity and reproduction speed and accelerating the decomposition of organic pollutants by microorganisms. The online monitoring and control system (13) is connected to the hydraulic fracturing device, the biological agent injection device, the cross-resistivity monitoring device, the pH driving device, and the thermal resistance driving device to monitor and control the operation of the entire remediation system online. The cross-resistivity monitoring device uses a power supply electrode to supply power to the underground while observing the potential difference at the measurement electrode and calculating the resistivity. The change of pollutant concentration is dynamically monitored through the change of resistivity over time, and the pollutant concentration in low-permeability clay is obtained based on Archie law The relationship between resistivity and resistivity （3） wherein is the porosity, is the contaminant concentration, is the water phase resistivity, is the total resistivity of all components, is the cementation exponent, is the resistivity of the soil particles; According to formula (3), the relationship between resistivity change and pollutant concentration change is: （4） wherein is a proportionality factor, representing the influence of the pollutant concentration on the change in resistivity; The rate of microbial decomposition of organic pollutants is directly measured by laboratory experiments to obtain the rate constant of microbial decomposition k The rate of microbial decomposition of organic pollutants is expressed as: （5） Assuming that the total amount of microorganisms M is proportional to the total amount of pollutants decomposed, the required amount of microorganisms is represented as: （6） wherein is a proportionality constant representing the amount of microorganisms required to decompose one unit of pollutant; Combining formula (4) to formula (6), the relationship between the microbial injection amount M and the change of the resistivity is: ​ （7） The online monitoring regulation system (13) is regulated according to the relationship between the above-mentioned microorganism injection amount M and the resistivity change .

2. The low-permeability contaminated stratum fracturing and biodegradation remediation system of claim 1, wherein: The holes formed in the casing (1) include fracturing injection holes (101), biological agent injection holes (102), and pH injection holes (103), and also include mounting holes for mounting temperature sensors (1004), pH sensors (903), temperature-variable resistors (1002), and electrodes (703).

3. The low-permeability contaminated stratum fracturing and biodegradation remediation system of claim 1, wherein: The hydraulic fracturing device comprises a hydraulic fracturing injection pump (801), a fracturing fluid injection pipe (802), and a fracturing fluid injection valve (803), wherein: The hydraulic fracturing injection pump (801) is connected to the fracturing fluid injection pipe (802), and the fracturing fluid injection valve (803) is arranged on the fracturing fluid injection pipe (802). The hydraulic fracturing injection pump (801) is connected to the online monitoring and control system (13) through a cable (12) and is controlled by the online monitoring and control system (13) to control the hydraulic fracturing process.

4. The low-permeability contaminated stratum fracturing and biodegradation remediation system of claim 1, wherein: The biological agent injection device comprises a biological agent injection pump (601), a biological agent injection pipe (602), and an intelligent flow control valve (603), wherein: The biological agent injection pump (601) is connected with the biological agent injection pipe (602), and the intelligent flow control valve (603) is arranged on the biological agent injection pipe (602). The biological agent injection pump (601) is connected with the online monitoring and control system (13) through the cable (12), and the injection process is controlled by the online monitoring and control system (13).

5. The low-permeability contaminated stratum pressurized biodegradation repair system of claim 1, wherein, The cross-resistivity monitoring device comprises a resistivity monitoring controller (701), an electrode line interface (702), an electrode line (706), an electrode (703), and a mobile power supply (704), wherein: The resistivity monitoring controller (701) is used for testing, analyzing resistivity data, and visualizing resistivity change ranges, and is provided with the electrode line interface (702). A plurality of electrodes (703) are connected to the electrode line interface (702) through the electrode line (706). The electrode (703) is in contact with soil. The mobile power supply (704) is connected to the resistivity monitoring controller (701) through the cable (12) to supply power to the resistivity monitoring controller (701). The resistivity monitoring controller (701) is connected to the online monitoring and control system (13) through the cable (12). The resistivity test and data analysis are performed by the resistivity monitoring controller (701), and the biological agent injection device is further controlled by the online monitoring and control system (13) according to the analysis result.

6. The low-permeability contaminated stratum pressurized biodegradation repair system of claim 1, wherein, The pH driving device comprises a pH injection pump (901), a pH controller (902), a pH sensor (903), a pH injection pipe (904), and a pH injection valve (905), wherein: The pH sensor (903) is arranged near the lower part of the fracture (3). The pH controller (902) and the pH sensor (903) are connected through a cable to form a pH test system for obtaining the pH value of a test area. The pH controller (902) and the pH injection pump (901) are connected through a cable to control the pH adjustment process. The pH injection pump (901) is connected with the pH injection pipe (904) and the pH injection valve (905) to form a pH adjustment system. The pH controller (902) is connected to the online monitoring and control system (13) through the cable (12). The pH test and pH adjustment process are controlled by the pH controller (902) according to the test result, and the pH controller (902) is further controlled by the online monitoring and control system (13) according to the test result.

7. The low-permeability contaminated stratum pressurized biodegradation repair system of claim 1, wherein, The thermal resistance driving device comprises a temperature controller (1001), a variable-temperature resistance (1002), a temperature sensor (1003), and a resistance adjustment valve (1004), wherein: The temperature control device (1001) is connected with the temperature sensor (1003) through the cable (12) for obtaining temperature information; the temperature control device (1001) is connected with the temperature variable resistor (1002) through the cable (12), and the cable is connected with the resistance adjusting valve (1004) for controlling the temperature variable resistor (1002) to change temperature according to the temperature information; the temperature control device (1001) is connected with the online monitoring and control system (13) through the cable (12), and the temperature test and temperature adjustment process are controlled by the online monitoring and control system (13).

8. A method for fracturing and bioremediation of a low permeable contaminated formation based on the system according to any one of claims 1 to 7, characterized in that, The implementation process includes the following steps: Step one: drilling and well construction; Step two: installing the repair system components; Step three: realizing hydraulic fracturing by using the hydraulic fracturing device; Ensure that the fracturing fluid injection pipe (802) is connected at the fracturing injection hole (101), open the hydraulic fracturing injection pump (801) of the hydraulic fracturing device through the online monitoring and control system (13), inject high-pressure water at the fracturing injection hole (101) to perform hydraulic fracturing, form a fracture (3) near the fracturing injection hole (101), and transport proppant in the fracture to form a medicament injection channel to prevent the fracture from closing; Step four: realizing cross-hole resistivity monitoring by using the cross-resistivity monitoring device; Connect all the electrodes (703) in the two underground wells with the electrode line interface (702) of the cross-resistivity monitoring device respectively, connect the mobile power supply (704) with the resistivity monitoring system (701), provide current according to the online monitoring and control system (13) control any two electrodes in the two underground wells, test the voltage of any two remaining electrodes, calculate the resistivity of the region between the two underground wells according to the resistivity test principle, monitor once every fixed time interval, and continuously monitor online; Step five: realizing repair medicament injection by using the biological medicament injection device; Prepare the microbial agent and growth promoter mixture, ensure that the biological medicament injection pipe (602) is connected to the biological medicament injection hole (102), open the biological medicament injection pump (601) by using the online monitoring and control system (13), and inject the microbial repair medicament into the fracture (3) along the biological medicament injection pipe (602), monitor the resistivity based on the relationship between the microbial injection amount and the resistivity change, and control the microbial injection amount and injection speed by using the online monitoring and control system (13); Step six: realizing pH and temperature environment driving by using the pH driving device and the thermal resistance driving device; According to the resistivity monitoring results fed back by the online monitoring and regulation system (13), the speed of pollutant decomposition and the repair area are obtained, the temperature sensor (1003) of the heat resistance driving device and the pH sensor (903) of the pH driving device are controlled by the online monitoring and regulation system (13) to test the environmental temperature and the pH value at the crack (3) respectively, according to the suitable pH value and temperature for the survival of microorganisms, the online monitoring and regulation system (13) starts the heat resistance driving device and the pH driving device, adjusts the soil temperature and pH, improves the microbial activity, speeds up the microbial decomposition of organic pollutants, improves the repair efficiency and expands the repair range; Step seven: resistivity monitoring, bioremediation, and environmental driving integration collaborative work; Step eight: recycling repair system; Step nine: reinstall the repair system in the next borehole to carry out bioremediation.

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