A method and system for remediating soil groundwater using a dissolved air injection integrated system.

Abstract

This invention discloses a method and system for remediating soil and groundwater using an integrated dissolved air injection system. The system comprises: a reagent preparation unit, a dissolved air injection unit, an atomizing and mixing unit, and an auxiliary unit. The reagent preparation unit includes a reagent dissolving tank and a dosing pump, with a stirrer inside the tank. The dissolved air injection unit includes an air compressor and a dissolved air tank. The atomizing and mixing unit includes a venturi tube, a liquid-gas connection pipe, and a switching valve. The auxiliary unit includes an electrical control cabinet and a mobile platform. The electrical control cabinets for the reagent preparation unit, dissolved air injection unit, atomizing and mixing unit, and the auxiliary unit are all integrated on the mobile platform. This invention also provides a method for remediating soil and groundwater using this system. By combining dissolved air injection and in-situ injection technologies, this invention achieves enhanced pollutant desorption and reagent dispersion through air-water flushing. By introducing process gases such as air (oxygen), methane, or hydrogen, it further enhances in-situ microbial remediation, achieving long-term, low-consumption, and green remediation.

Description

Technical Field

[0001] This invention relates to an in-situ injection technology and equipment for environmental remediation, specifically, to a method and system for in-situ remediation of soil and groundwater pollution using a mobile dissolved air injection integrated system. Background Technology

[0002] In recent years, the soil remediation industry has developed rapidly. Soil and groundwater in various contaminated sites have been remediated and treated using physical, chemical and other engineering technologies. However, bioremediation technology has not become a mainstream application due to its long implementation cycle.

[0003] Physical remediation (such as thermal treatment and steam extraction) and chemical remediation (such as advanced oxidation techniques and leaching / extraction remediation techniques) can effectively remediate organically contaminated soils, but their drawback is that they can severely damage the physical and chemical properties of the soil and the living environment of microorganisms.

[0004] Bioremediation is considered an economical and environmentally friendly soil remediation technology due to its advantages such as no secondary pollution and low cost. With the strengthening of green and sustainable remediation concepts and the increasing emphasis on cost-effectiveness and long-term monitoring of contaminated site remediation, the advantages of bioremediation technology will gradually become more prominent. However, the remediation efficiency of bioremediation is, to some extent, limited by species territoriality and bioavailability. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for enhancing in-situ microbial remediation of soil and groundwater pollution using a mobile dissolved air injection integrated system. By combining dissolved air technology with engineering technologies such as in-situ injection, a gas-water flushing process is formed to enhance pollutant desorption and reagent dispersion. By introducing process gases such as air (oxygen), methane, or hydrogen, in-situ microbial remediation is further enhanced, achieving long-term, low-consumption, and green remediation.

[0006] To achieve the above objectives, the present invention provides an integrated dissolved air injection system for remediating soil groundwater. The integrated dissolved air injection system comprises: a reagent preparation unit, a dissolved air injection unit, an atomizing and mixing unit, and an auxiliary unit. The reagent preparation unit includes a reagent dissolving tank and a dosing pump, with a stirrer installed inside the tank. The dissolved air injection unit includes an air compressor and a dissolved air tank. The atomizing and mixing unit includes a venturi tube, a liquid-gas connection pipe, and a switching valve. The auxiliary unit includes an electrical control cabinet and a mobile platform. The electrical control cabinets of the reagent preparation unit, the dissolved air injection unit, the atomizing and mixing unit, and the auxiliary unit are all integrated on the mobile platform.

[0007] The aforementioned integrated dissolved air injection system for soil and groundwater remediation includes a reagent preparation unit comprising a reagent dissolving tank, a dosing pump, and a mixer. The reagent dissolving tank is equipped with a tap water inlet, a solid reagent / concentrated reagent dosing inlet, a tank level gauge, and a tank vent valve. The dissolved air injection unit comprises an air compressor, a dissolved air tank, and supporting components for the dissolved air injection process, including a dissolved air tank process gas inlet, a dissolved air tank reagent inlet control valve, a dissolved air tank bottom inlet control valve, and a dissolved air tank bottom valve. The dissolved gas distribution head, dissolved gas tank top gas-liquid balance valve, dissolved gas injection control valve, and dissolved gas injection pipeline interface are included. The dissolved gas tank is equipped with a dissolved gas tank level gauge, dissolved gas tank pressure gauge, dissolved gas tank pressure relief valve, dissolved gas tank exhaust valve, dissolved gas tank emptying valve, and dissolved gas tank outlet back pressure valve. The atomizing and mixing unit includes a venturi tube, as well as a venturi tube inlet control valve, atomizing suction control valve, mixing suction control valve, and venturi tube outlet control valve located at the injection pipeline interface, which are used in conjunction with the atomizing injection / mixing injection process.

[0008] The aforementioned dissolved air injection integrated system for soil and groundwater remediation includes a liquid reagent preparation unit that prepares the liquid reagent by manually adding solid or liquid reagent concentrates into the dissolving tank according to the preparation ratio, then adding tap water through the tap water inlet, and finally stirring the solution with a mixer to form a liquid reagent for remediation.

[0009] The aforementioned integrated dissolved air injection system for soil and groundwater remediation comprises the following: The integrated system uses a dissolved air injection unit to prepare the dissolved air agent. After the liquid agent is prepared, the dosing pump of the preparation unit is activated to deliver the liquid agent to the dissolved air tank. Following the dissolved air procedure, valves are switched and an air compressor is started to introduce compressed air into the dissolved air tank. The compressed air is then dispersed into the liquid agent through an air distributor to fully dissolve it, creating a supersaturated state. Once the dissolved air tank reaches the preset dissolved air injection pressure, a dissolved air agent ready for remediation is formed. The integrated system uses the dissolved air injection unit to inject the dissolved air agent. After the dissolved air agent is prepared... Connect the dissolved air injection pipeline to the injection rod or injection well. After opening the dissolved air injection control valve, the liquid agent containing compressed air is delivered to the injection rod or injection well for injection, and dispersed to the repair formation at the preset repair depth. During the injection process, the amount of dissolved air agent injected at a single point and depth is adjusted and controlled by the liquid level in the dissolved air tank and the pipeline valves. After the injection at the injection point is completed, it is moved to the next batch of injection points. The integrated system achieves constant pressure buffered individual injection of liquid agent through the dissolved air injection unit: after the liquid agent is prepared, the dosing pump of the agent preparation unit is started to deliver the liquid agent to the dissolved air injection unit. The system, following a constant-pressure liquid agent injection procedure, switches valves and starts the air compressor to introduce compressed air into the headspace of the dissolved air tank. Once the preset injection pressure is reached, the injection pipeline is connected to the injection rod or injection well. The injection control valve is opened, and the liquid agent is delivered to the injection rod or injection well for injection. At the preset repair depth, the liquid agent is then output under pressure and dispersed into the repair formation. During injection, the liquid level in the dissolved air tank and the pipeline valves are adjusted to control the injection volume at individual points and depths. After injection at one point, the system moves to the next batch of injection points. The integrated system utilizes the dissolved air injection unit to achieve compressed air injection... Constant pressure buffered individual injection: After ensuring that the liquid in the dissolved air tank is emptied, switch the valves and start the air compressor according to the constant pressure injection procedure of compressed air. After the compressed air in the dissolved air tank reaches the preset air injection pressure value, connect the air injection pipeline to the injection rod or injection well, open the air injection control valve, and deliver the compressed air to the injection rod or injection well for injection. The compressed air is then output under pressure at the preset repair depth and dispersed to the repair formation. During the injection process, the air injection volume and injection time of a single point and a single depth are adjusted and controlled by the air pressure in the dissolved air tank and the pipeline valves. After the injection at the injection point is completed, the injection point is moved to the next batch of injection points.

[0010] The aforementioned integrated dissolved air injection system for soil and groundwater remediation, wherein the integrated system achieves atomized injection through a reagent preparation unit, a dissolved air injection unit, and a venturi tube in an atomizing mixing unit: After the liquid reagent is prepared, the liquid in the dissolved air tank is emptied, and then the air compressor is started. After the compressed air reaches the preset atomization injection pressure value in the dissolved air tank, the atomization injection pipeline is connected to the injection rod or injection well, and the atomization injection control valve and the atomization suction control valve are opened. The compressed air moves at high speed through the narrow opening in the venturi tube and is suddenly depressurized. A localized negative pressure is generated, causing a siphon effect that draws the liquid agent from the Venturi tube into another small pipe next to the airflow outlet. The liquid agent, upon encountering the high-pressure airflow, is impacted and broken into small aerosol particles, which are then carried out with the airflow and transported through an atomization injection pipeline to the injection rod or injection well for injection. The atomized agent is dispersed to the repaired formation at a preset repair depth. During injection, the liquid level in the dissolving tank and the pipeline valves jointly regulate and control the injection volume of the atomized agent at each point and depth, and after injection at one point, it is moved to the next batch of injection points. The integrated system... The system, through the reagent preparation unit and the dissolved gas injection unit, combined with the Venturi tube in the atomizing gas mixing unit, achieves gas-liquid injection: After the liquid reagent is prepared, the dosing pump of the reagent preparation unit is started to deliver the liquid reagent to the dissolved gas tank. The air compressor is started, and after the compressed air reaches the preset gas-liquid injection pressure value in the headspace of the dissolved gas tank, the integrated system is switched to the pipeline valve status of the gas-liquid injection mode to ensure that the process gas supply pipeline is correctly connected. Then, the gas-liquid injection pipeline is connected to the injection rod or injection well, and the gas-liquid injection control valve and the gas-liquid suction control valve are opened, allowing the liquid reagent to be injected. The agent is pressurized by the dissolved gas tank and sent to the Venturi tube, where it is ejected from the nozzle at a high speed. By creating a vacuum in the nozzle outlet area, the process gas is drawn in through the mixing pipeline and thoroughly mixed with the liquid agent. The liquid agent mixed with the process gas is then transported to the injection rod or injection well through the mixed gas injection pipeline for injection. It is then output and dispersed to the formation to be repaired at the preset repair depth. During the injection process, the amount of mixed gas agent injected at a single point and a single depth is adjusted and controlled by the liquid level in the dissolved gas tank and the valves in the process gas pipeline. After the injection at the injection point is completed, the agent is moved to the next batch of injection points.

[0011] This invention also provides a method for remediating soil groundwater using the above-mentioned dissolved air injection integrated system, wherein the method includes: a reagent injection mode, an air injection mode, a dissolved air injection mode, an atomized injection mode, and a mixed air injection mode; the reagent injection mode includes: step 1.1, moving the mobile platform to the vicinity of the injection point and connecting it to an AC power source and a tap water source; step 1.2, opening the tap water valve and injecting tap water into the tap water inlet of the reagent dissolving tank, observing the liquid level in the reagent dissolving tank through the tank level gauge and controlling the amount of tap water added; step 1.3, starting the mixer and adding solid reagent to the solid reagent / concentrated reagent dosing port of the reagent dissolving tank. The agent / concentrate is stirred to form a liquid agent for repair; Step 1.4: Open the dissolved gas tank inlet control valve, start the dosing pump, and transfer the prepared liquid agent to the dissolved gas tank; Step 1.5: Observe the liquid level in the dissolved gas tank through the liquid level gauge. After reaching the preset liquid agent addition amount, stop the dosing pump and close the dissolved gas tank inlet control valve; Step 1.6: Open the gas-liquid balance valve on the top of the dissolved gas tank on the pipeline connecting the air compressor and the dissolved gas tank; Step 1.7: Start the air compressor, and compressed air pressurizes the dissolved gas tank through the gas-liquid balance valve on the top of the dissolved gas tank until the liquid agent reaches the pressure value required for repair; Step 1.8: Add the liquid agent to the dissolved gas tank through the dissolved gas injection pipeline interface. The agent injection pipeline is connected to the injection rod or injection well via an injection hose; Step 1.9: Open the dissolved gas injection control valve. Under the constant pressure maintained by the air compressor in the dissolved gas tank, the liquid agent is distributed under pressure to the repair formation through the injection rod or injection well at the preset repair depth; Step 1.10: Observe the liquid level in the dissolved gas tank through the dissolved gas tank level gauge. After reaching the preset agent injection volume, close the dissolved gas injection control valve; Step 1.11: When using rod injection, move the injection rod to the next injection depth. Repeat steps 1.9 to 1.10 until all designed injection depths at the injection point have been completed. Then connect the agent injection pipeline to the next injection point. For the next injection point, connect the injection pipeline to the next injection point and repeat steps 1.8 to 1.11. When the reagent runs out, repeat steps 1.2 to 1.11 until all designed injection points have been injected. When using well injection, connect the reagent injection pipeline to the next injection point and repeat steps 1.8 to 1.11. When the reagent runs out, repeat steps 1.2 to 1.11 until all designed injection points have been injected. In step 1.12, after completing all injection operations, close the dissolved gas injection control valve, shut down the air compressor, release the pressure in the dissolved gas tank through the dissolved gas tank exhaust valve, and empty the excess liquid reagent in the dissolved drug tank and the dissolved gas tank through the dissolved drug tank exhaust valve and the dissolved gas tank exhaust valve, respectively.

[0012] The above-described method for remediating soil groundwater using a dissolved air injection integrated system includes the following steps in the air injection mode: Step 2.1, moving the mobile platform to the vicinity of the injection point and connecting it to an AC power source; Step 2.2, opening the gas-liquid balance valve on the top of the dissolved air tank on the pipeline connecting the air compressor and the dissolved air tank; Step 2.3, after ensuring the liquid in the dissolved air tank is emptied, starting the air compressor and running it until the compressed air in the dissolved air tank reaches the pressure value required for remediation; Step 2.4, connecting the air injection pipeline to the injection rod or injection well via an injection hose through the dissolved air injection pipeline interface; Step 2.5, opening the dissolved air injection control valve, allowing compressed air to be output under pressure and dispersed into the remediation stratum through the injection rod or injection well at the preset remediation depth; Step 2.6, observing the dissolved air pressure through the dissolved air tank pressure gauge. After the pressure of the compressed air in the gas tank reaches the target air injection time at the preset pressure, close the dissolved air injection control valve; Step 2.7, when using rod injection, move the injection rod to the next injection depth and repeat steps 2.5 to 2.6 until all designed injection depths at the injection point have been filled with air. Then connect the air injection pipeline to the next injection point and repeat steps 2.4 to 2.7 until all designed injection points have been filled with air; when using well injection, connect the air injection pipeline to the next injection point and repeat steps 2.4 to 2.7 until all designed injection points have been filled with air; Step 2.8, after completing all injection operations, close the dissolved air injection control valve, shut down the air compressor, and release the pressure in the dissolved air tank through the dissolved air tank exhaust valve.

[0013] The above-mentioned method for remediating soil groundwater using a dissolved air injection integrated system includes the following steps: Step 3.1, moving the mobile platform to the vicinity of the injection point and connecting it to an AC power source and a tap water source; Step 3.2, opening the tap water valve and injecting tap water into the tap water inlet of the dissolving tank, observing the liquid level in the dissolving tank through the tank level gauge and controlling the amount of tap water added; Step 3.3, starting the mixer and adding solid reagent / concentrated reagent into the solid reagent / concentrated reagent inlet of the dissolving tank, stirring to form a liquid reagent for remediation; Step 3.4, opening the dissolved air tank inlet control valve and starting the dosing pump to... The prepared liquid reagent is transferred to the dissolved gas tank; Step 3.5: Observe the liquid level in the dissolved gas tank through the liquid level gauge. After reaching the preset amount of liquid reagent added, stop the dosing pump and close the dissolved gas tank inlet control valve; Step 3.6: Open the air inlet control valve at the bottom of the dissolved gas tank on the connection pipeline between the air compressor and the dissolved gas tank; Step 3.7: Start the air compressor, and the compressed air is dispersed into the liquid reagent through the dissolved gas distribution head at the bottom of the dissolved gas tank until the dissolved gas reagent reaches the pressure value for repair use. Then, close the air inlet control valve at the bottom of the dissolved gas tank and open the gas-liquid balance valve at the top of the dissolved gas tank to maintain the gas-liquid balance and reagent injection pressure in the dissolved gas tank; Step 3.8: Through the dissolved gas injection pipeline interface... Connect the dissolved gas injection pipeline to the injection rod or injection well via an injection hose; Step 3.9: Open the dissolved gas injection pipeline interface, and the dissolved gas agent is pressurized and dispersed into the repair formation through the injection rod or injection well at the preset repair depth; Step 3.10: Observe the liquid level in the dissolved gas tank through the dissolved gas tank level gauge. After reaching the preset dissolved gas agent injection volume, close the dissolved gas injection pipeline interface; Step 3.11: When using rod injection, move the injection rod to the next injection depth and repeat steps 3.9 to 3.10 until all designed injection depths at the injection point have been dissolved gas injected. Then connect the dissolved gas injection pipeline to the next injection point and repeat steps 3.8 to 3.10. 3.11 When the reagent is used up, repeat steps 3.2 to 3.11 until all designed injection points have been injected with dissolved gas. When using well injection, connect the dissolved gas injection pipeline to the next injection point and repeat steps 3.8 to 3.11. When the reagent is used up, repeat steps 3.2 to 3.11 until all designed injection points have been injected with dissolved gas. Step 3.12 After completing all injection operations, close the dissolved gas injection control valve 22, shut down the air compressor 8, release the pressure in the dissolved gas tank 10 through the dissolved gas tank exhaust valve 14, and drain the excess liquid reagent in the drug dissolving tank 5 and the dissolved gas tank 10 through the drug dissolving tank exhaust valve 6 and the dissolved gas tank exhaust valve 15, respectively.

[0014] The above-described method for remediating soil groundwater using a dissolved air injection integrated system includes the following steps in the atomization injection mode: Step 4.1, moving the mobile platform to the vicinity of the injection point and connecting it to an AC power source and a tap water source; Step 4.2, opening the tap water valve and injecting tap water into the tap water inlet of the dissolving tank, observing the liquid level in the dissolving tank through the tank level gauge and controlling the amount of tap water added; Step 4.3, starting the mixer and adding solid agent / concentrated agent to the solid agent / concentrated agent inlet of the dissolving tank, stirring to form a liquid agent for remediation; Step 4.4, ensuring that the liquid in the dissolved air tank is emptied, and then opening the air valve. Step 4.5: Connect the air compressor to the dissolved air tank via the gas-liquid balance valve on the top of the dissolved air tank. Start the air compressor and run it until the compressed air in the dissolved air tank reaches the pressure value required for repair. Step 4.6: Connect the atomization injection pipeline to the injection rod or injection well via the injection hose through the Venturi tube outlet control valve. Step 4.7: Open the Venturi tube outlet control valve, Venturi tube inlet control valve, and atomization suction control valve. The compressed air moves at high speed through the narrow opening inside the Venturi tube and is suddenly depressurized, creating a local negative pressure. This negative pressure causes the liquid agent drawn in by the other small tube connected to the atomization suction control valve next to the air outlet to be discharged. The liquid agent encounters high pressure air... During flow, the aerosol particles are broken down into small particles by impact and output with the airflow. They are then dispersed under pressure at the preset remediation depth through the injection rod or injection well, reaching the small soil pores in the vadose zone. Step 4.7: Observe the liquid level in the dissolving tank using the tank level gauge. Once the preset atomized agent injection volume is reached, close the Venturi tube outlet control valve, Venturi tube inlet control valve, and atomization suction control valve. Step 4.8: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 4.6 to 4.7 until all designed injection depths at that injection point have been atomized. Then connect the atomization injection pipeline to the next injection point and repeat. Steps 4.5 to 4.8: When the reagent runs out, repeat steps 4.2 to 4.8 until all designed injection points have been nebulized. When using well injection, connect the nebulization injection pipeline to the next injection point and repeat steps 4.5 to 4.8. When the reagent runs out, repeat steps 4.2 to 4.8 until all designed injection points have been dissolved in gas. Step 4.9: After completing all injection operations, close the Venturi tube outlet control valve, Venturi tube inlet control valve, and nebulization suction control valve. Turn off the air compressor, release the pressure in the dissolved gas tank through the dissolved gas tank exhaust valve, and drain the excess liquid reagent in the dissolved gas tank through the dissolved gas tank vent valve.

[0015] The above-mentioned method for remediating soil groundwater using a dissolved air injection integrated system includes the following steps in the gas injection mode: Step 5.1, moving the mobile platform to the vicinity of the injection point and connecting it to an AC power source and a tap water source; Step 5.2, opening the tap water valve and injecting tap water into the tap water inlet of the dissolving tank, observing the liquid level in the dissolving tank through the tank level gauge and controlling the amount of tap water added; Step 5.3, starting the mixer and adding solid agent / concentrated agent to the solid agent / concentrated agent inlet of the dissolving tank, stirring to form a liquid agent for remediation; Step 5.4, opening the dissolved air tank inlet control valve, starting the dosing pump, and transferring the prepared liquid agent to the dissolved air tank; Step 5.5, [further steps to be added]. Observe the liquid level in the dissolved gas tank using the level gauge. Once the preset liquid agent addition amount is reached, stop the dosing pump and close the dissolved gas tank inlet control valve. Step 5.6: Open the gas-liquid balance valve on the top of the dissolved gas tank on the connection pipeline between the air compressor and the dissolved gas tank. Step 5.7: Start the air compressor; compressed air is pressurized into the dissolved gas tank through the gas-liquid balance valve on top until the liquid agent reaches the pressure value required for repair. Step 5.8: Connect the mixed gas injection pipeline to the injection rod or injection well via the injection hose through the Venturi tube outlet control valve. Step 5.9: Open the Venturi tube outlet control valve, Venturi tube inlet control valve, and mixed gas suction control valve. The liquid agent is pressurized by the dissolved gas tank and sent to the Venturi tube, then sprayed out at high speed from the nozzle inside the tube. A vacuum is created in the nozzle outlet area. The process gas is drawn in through the mixing pipeline connected to the mixing pipeline near the nozzle outlet via the mixing pipeline control valve and thoroughly mixed with the liquid reagent. The liquid reagent mixed with the process gas is then dispersed under pressure to the repair formation through the injection rod or injection well at the preset repair depth. In step 5.10, the liquid level in the dissolved gas tank is observed using the dissolved gas tank level gauge. Once the preset dissolved gas reagent injection volume is reached, the Venturi tube outlet control valve, Venturi tube inlet control valve, and mixing pipeline control valve are closed. In step 5.11, when using a rod-type injection, the injection rod is moved to the next injection depth. Steps 5.9 to 5.10 are repeated until all designed injection depths at that injection point have been mixed with the liquid reagent. Then, the mixing pipeline is connected to the next injection point. For the next injection point, repeat steps 5.8 to 5.11. When the reagent is used up, repeat steps 5.2 to 5.11 until all designed injection points have completed atomized injection. When using well injection, connect the mixed gas injection pipeline to the next injection point and repeat steps 5.8 to 5.11. When the reagent is used up, repeat steps 5.2 to 5.11 until all designed injection points have completed dissolved gas injection. Step 5.12: After completing all injection operations, close the Venturi tube outlet control valve, Venturi tube inlet control valve, and mixed gas intake control valve. Turn off the air compressor. Release the pressure in the dissolved gas tank through the dissolved gas tank exhaust valve and drain the excess liquid reagent in the drug dissolving tank and dissolved gas tank through the drug dissolving tank exhaust valve and the dissolved gas tank exhaust valve, respectively.

[0016] The method and system for remediating soil groundwater using a dissolved air injection integrated system provided by this invention have the following advantages:

[0017] (1) Based on the improvement of traditional liquid and gas injection methods to form constant pressure buffer agent injection and air injection process, the dissolved gas injection integrated system has developed and integrated different forms of gas-liquid dispersion and mixing injection processes such as dissolved gas injection, atomization injection and mixed gas injection. Different injection processes or process combinations can be flexibly selected to meet the needs of different soil and groundwater remediation scenarios.

[0018] (2) The dissolved gas injection integrated system can be connected to the injection rod or injection well through the injection hose and can be applied to rod injection and well injection respectively. Rod injection can be combined with the pollution depth and formation information for real-time and accurate injection, while well injection can achieve multiple rounds of low-cost injection while combining different depths of injection wells.

[0019] (3) Using the principle of pressurized dissolved air, supersaturated air is dissolved in the liquid agent and dispersed to the preset depth of the remediation layer through the injection rod or injection well. As the pressure decreases and the dissolved air is released, the scouring, shearing and lifting effect of the bubbles causes the pollutants to desorb from the surface of soil particles and diffuse and migrate to groundwater. At the same time, it helps the remediation agent to fully contact and mix with the pollutants, forming an underground environment conducive to aerobic remediation by microorganisms, which can achieve the effect of in-situ microbial enhanced aerobic remediation.

[0020] (4) By utilizing the atomization principle of the Venturi tube, a uniformly dispersed liquid agent atomized droplets are formed in the high-speed compressed air flow, so that the liquid agent can enter the vadose zone and be more evenly distributed in the soil pores and microchannels after being injected, thereby improving the dispersion and diffusion effect of the remediation agent and improving the vadose zone remediation effect that is difficult to achieve with traditional injection methods.

[0021] (5) Using the Venturi tube ejector principle, uniformly dispersed process gases (such as methane, hydrogen, etc.) are mixed into the liquid agent. After the liquid agent mixed with process gases is injected into the pre-set depth of the remediation stratum, the underground environment conducive to microbial anaerobic reduction remediation is formed under the combined action of the injected reducing remediation agent and the slowly released process gases, which can realize the in-situ microbial enhanced anaerobic reduction remediation effect.

[0022] (6) The dissolved gas injection system is integrated on a mobile platform, which is convenient for lifting and transportation, saves the time required for disassembly, assembly and debugging, reduces the labor intensity of construction personnel and improves the efficiency of remediation construction. The integrated system can be quickly selected and switched between different injection processes through automatic settings or manual operation to adapt to the process requirements of different soil and groundwater remediation scenarios, enhance pollutant desorption and agent material dispersion and mixing, introduce process gases that are conducive to aerobic and anaerobic bioremediation, thereby improving the in-situ microbial remediation environment, improving remediation efficiency, enhancing remediation effect, and achieving long-term, low-consumption microbial enhanced green remediation. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the method and system composition and process flow for remediating soil groundwater using a dissolved air injection integrated system according to the present invention.

[0024] The components include: 1. Dissolving tank; 2. Tap water inlet; 3. Solid drug / concentrated drug solution dosing inlet; 4. Agitator; 5. Dissolving tank level gauge; 6. Dissolving tank vent valve; 7. Dosing pump; 8. Air compressor; 9. Air compressor outlet control valve; 10. Dissolved gas tank; 11. Dissolved gas tank level gauge; 12. Dissolved gas tank pressure gauge; 13. Dissolved gas tank pressure relief valve; 14. Dissolved gas tank exhaust valve; 15. Dissolved gas tank vent valve; 16. Dissolved gas tank outlet back pressure valve; 17. Dissolved gas tank process gas... 18. Dissolved gas tank inlet control valve; 19. Dissolved gas tank bottom inlet control valve; 20. Dissolved gas tank bottom gas distribution head; 21. Dissolved gas tank top gas-liquid balance valve; 22. Dissolved gas injection control valve; 23. Dissolved gas injection pipeline interface; 24. Venturi tube inlet control valve; 25. Nebulizer inhalation control valve; 26. Venturi tube; 27. Venturi tube outlet control valve; 28. Mixed gas injection process gas inlet; 29. ​​Electrical control cabinet; 30. Mobile platform. Detailed Implementation

[0025] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0026] like Figure 1 As shown, the dissolved air injection integrated system for soil and groundwater remediation provided by the present invention includes: a reagent preparation unit, a dissolved air injection unit, an atomizing and mixing unit, and an auxiliary unit; the reagent preparation unit includes a reagent dissolving tank 1 and a dosing pump 7, and a mixer 4 is provided inside the reagent dissolving tank 1; the dissolved air injection unit includes an air compressor 8 and a dissolved air tank 10; the atomizing and mixing unit includes a venturi tube 26, a liquid-gas connection pipe, and a switching valve; the auxiliary unit includes an electrical control cabinet 29 and a mobile platform 30; the electrical control cabinet 29 of the reagent preparation unit, the dissolved air injection unit, the atomizing and mixing unit, and the auxiliary unit are all integrated on the mobile platform 30.

[0027] Preferably, in this integrated system, the drug preparation unit includes a dissolving tank 1, a dosing pump 7, and a mixer 4. The dissolving tank 1 is equipped with a tap water inlet 2, a solid drug / drug concentrate dosing inlet 3, a dissolving tank level gauge 5, and a dissolving tank vent valve 6. The dissolved gas injection unit includes an air compressor 8, a dissolved gas tank 10, an air compressor outlet control valve 9, and a dissolved gas tank process gas inlet 17, a dissolved gas tank drug inlet control valve 18, a dissolved gas tank bottom air inlet control valve 19, a dissolved gas tank bottom dissolved gas distribution head 20, and a dissolved gas tank top air distribution head. The system includes a liquid balance valve 21, a dissolved gas injection control valve 22, and a dissolved gas injection pipeline interface 23; the dissolved gas tank 10 is equipped with a dissolved gas tank level gauge 11, a dissolved gas tank pressure gauge 12, a dissolved gas tank pressure relief valve 13, a dissolved gas tank exhaust valve 14, a dissolved gas tank venting valve 15, and a dissolved gas tank outlet back pressure valve 16; the atomizing and mixing unit includes a venturi tube 26, and a venturi tube inlet control valve 24, an atomizing suction control valve 25, a mixing suction control valve 28, and a venturi tube outlet control valve 27 located at the injection pipeline interface for the atomizing injection / mixing injection process.

[0028] The integrated system uses a reagent preparation unit to prepare liquid reagents: solid reagents or liquid reagent concentrates are manually added into the dissolving tank according to the preparation ratio, and then tap water is added from the tap water inlet. After being stirred by a mixer, a liquid reagent for repair is formed.

[0029] The integrated system uses a dissolved gas injection unit to prepare dissolved gas agents: after the liquid agent is prepared, the dosing pump of the agent preparation unit is started to deliver the liquid agent to the dissolved gas tank. The valves are switched according to the dissolved gas program and the air compressor is started to introduce compressed air into the dissolved gas tank and disperse it into the liquid agent through the air distribution head to fully dissolve it and form a supersaturated state. After the dissolved gas tank reaches the preset dissolved gas injection pressure value, a dissolved gas agent for repair is formed.

[0030] This integrated system uses a dissolved gas injection unit to inject dissolved gas agents: after the dissolved gas agents are prepared, the dissolved gas injection pipeline is connected to the injection rod or injection well. After the dissolved gas injection control valve is opened, the liquid agent containing compressed air is delivered to the injection rod or injection well for injection, and then dispersed to the repair formation at the preset repair depth. During the injection process, the amount of dissolved gas agent injected at a single point and a single depth is adjusted and controlled by the liquid level of the dissolved gas tank and the pipeline valves. After the injection at the injection point is completed, the system moves to the next batch of injection points.

[0031] This integrated system achieves constant-pressure buffered individual injection of liquid agents through a dissolved gas injection unit: After the liquid agent is prepared, the dosing pump of the agent preparation unit is started to deliver the liquid agent to the dissolved gas tank. The valves are switched and the air compressor is started according to the constant-pressure injection procedure to introduce compressed air into the headspace of the dissolved gas tank. After the preset agent injection pressure value is reached, the agent injection pipeline is connected to the injection rod or injection well, the agent injection control valve is opened, and the liquid agent is delivered to the injection rod or injection well for injection. It is then output under pressure at the preset repair depth and dispersed to the repair formation. During the injection process, the liquid agent injection volume at a single point and a single depth is controlled by adjusting the liquid level in the dissolved gas tank and the pipeline valves. After the injection at the injection point is completed, it is moved to the next batch of injection points.

[0032] This integrated system achieves constant-pressure buffered individual injection of compressed air through a dissolved air injection unit: After ensuring that the liquid in the dissolved air tank is emptied, the valves are switched and the air compressor is started according to the constant-pressure compressed air injection procedure. After the compressed air in the dissolved air tank reaches the preset air injection pressure value, the air injection pipeline is connected to the injection rod or injection well, the air injection control valve is opened, and the compressed air is delivered to the injection rod or injection well for injection. The compressed air is then output under pressure at the preset repair depth and dispersed to the repair formation. During the injection process, the air injection volume and injection time of a single point and a single depth are jointly regulated and controlled by the air pressure in the dissolved air tank and the pipeline valves. After the injection at the injection point is completed, the system moves to the next batch of injection points.

[0033] This integrated system achieves atomized injection through a drug preparation unit, a dissolved gas injection unit, and a venturi tube in the atomization mixing unit: After the liquid drug is prepared, the liquid in the dissolved gas tank is emptied, and then the air compressor is started. After the compressed air reaches the preset atomization injection pressure value in the dissolved gas tank, the atomization injection pipeline is connected to the injection rod or injection well. The atomization injection control valve and the atomization suction control valve are opened. The compressed air moves at high speed through the narrow opening in the venturi tube and is suddenly depressurized, generating a negative pressure in a local area. The liquid drug is drawn into the venturi tube by the negative pressure through another small tube next to the air outlet and discharged. When the liquid drug encounters the high-pressure airflow, it is impacted and broken into small aerosol particles and output with the airflow. It is then transported to the injection rod or injection well through the atomization injection pipeline for injection and dispersed into the repair formation at the preset repair depth. During the injection process, the liquid level in the drug tank and the pipeline valves are used to adjust and control the injection volume of the atomized drug at a single point and a single depth. After the injection at the injection point is completed, it is moved to the next batch of injection points.

[0034] This integrated system achieves gas-liquid injection through a reagent preparation unit, a dissolved gas injection unit, and a venturi tube in the atomizing gas-mixing unit: After the liquid reagent is prepared, the dosing pump of the reagent preparation unit is started to deliver the liquid reagent to the dissolved gas tank. The air compressor is started, and after the compressed air reaches the preset gas-liquid injection pressure value in the headspace of the dissolved gas tank, the integrated system is switched to the pipeline valve state in the gas-liquid injection mode. This ensures the correct connection of the process gas supply pipeline. Subsequently, the gas-liquid injection pipeline is connected to the injection rod or injection well, and the gas-liquid injection control valve and the gas-liquid suction control valve are opened. The agent is pressurized by the dissolved gas tank and sent to the Venturi tube, where it is ejected from the nozzle at a high speed. A vacuum is created in the nozzle outlet area, which draws in the process gas through the mixing pipeline and mixes it thoroughly with the liquid agent. The liquid agent mixed with the process gas is then transported to the injection rod or injection well through the mixed gas injection pipeline for injection. It is then dispersed into the formation to be repaired at the preset repair depth. During the injection process, the amount of mixed gas agent injected at a single point and a single depth is adjusted and controlled by the liquid level in the dissolved gas tank and the valves in the process gas pipeline. After the injection at the injection point is completed, the agent is moved to the next batch of injection points.

[0035] The present invention also provides a method for remediating soil groundwater using the dissolved air injection integrated system, the method comprising: agent injection mode, air injection mode, dissolved air injection mode, atomized injection mode, and mixed air injection mode.

[0036] The following describes in more detail the method and system for remediating soil and groundwater using an integrated dissolved air injection system provided by the present invention, with reference to specific embodiments.

[0037] Example 1

[0038] An integrated dissolved air injection system for soil groundwater remediation includes components such as a reagent preparation unit, a dissolved air injection unit, an atomizing and mixing unit, and auxiliary units.

[0039] The drug preparation unit includes a dissolving tank 1 (including a mixer 4) and a dosing pump 7; the dissolved gas injection unit includes an air compressor 8 and a dissolved gas tank 10; the atomizing gas mixing unit includes a venturi tube 26 and a liquid-gas connection pipe and a switching valve; the auxiliary unit includes an electrical control cabinet 29 and a mobile platform 30; the electrical control cabinet 29 in the drug preparation unit, dissolved gas injection unit, atomizing gas mixing unit and auxiliary unit are all integrated on the mobile platform 30.

[0040] Preferably, the drug preparation unit includes a dissolving tank 1, a mixer 4, and a dosing pump 7; wherein, the dissolving tank 1 includes a tap water inlet 2, a solid drug / drug concentrate dosing inlet 3, a dissolving tank level gauge 5, and a dissolving tank drain valve 6.

[0041] The dissolved gas injection unit includes an air compressor 8, a dissolved gas tank 10, an air compressor outlet control valve 9, and a dissolved gas tank process gas inlet 17, a dissolved gas tank drug inlet control valve 18, a dissolved gas tank bottom air inlet control valve 19, a dissolved gas tank bottom dissolved gas distribution head 20, a dissolved gas tank top gas-liquid balance valve 21, a dissolved gas injection control valve 22, and a dissolved gas injection pipeline interface 23; wherein, the dissolved gas tank 10 includes a dissolved gas tank level gauge 11, a dissolved gas tank pressure gauge 12, a dissolved gas tank pressure relief valve 13, a dissolved gas tank exhaust valve 14, a dissolved gas tank venting valve 15, and a dissolved gas tank outlet back pressure valve 16.

[0042] The atomizing and mixing unit includes a venturi tube 26, as well as a venturi tube inlet control valve 24, an atomizing suction control valve 25, a venturi tube outlet control valve 27 (located at the injection pipe interface), and a mixing suction control valve 28, which are used for the atomizing injection / mixing injection process.

[0043] The auxiliary unit includes an electrical control cabinet 29 and a mobile platform 30. The drug preparation unit, dissolved gas injection unit, atomization mixing unit, and electrical control cabinet 29 in the auxiliary unit are all integrated on the mobile platform 30.

[0044] The integrated system uses a reagent preparation unit to prepare liquid reagents: first, a certain amount of solid reagent or liquid reagent stock solution is manually added into the dissolving tank according to the preparation ratio, then a certain proportion of tap water is added from the tap water inlet, and after being stirred by a mixer for a certain period of time, a liquid reagent that can be used for repair is formed.

[0045] This integrated system uses a dissolved gas injection unit to prepare dissolved gas reagents. After the liquid reagent is prepared, the dosing pump in the reagent preparation unit is started to deliver the liquid reagent to the dissolved gas tank. Following the dissolved gas procedure, valves are switched and the air compressor is started to introduce compressed air into the dissolved gas tank. The compressed air is then dispersed into the liquid reagent through an air distributor to fully dissolve it, creating a supersaturated state. Once the dissolved gas tank reaches the preset dissolved gas injection pressure, a dissolved gas reagent suitable for repair is formed. Specifically, other process gases (such as oxygen, methane, and hydrogen) can be introduced to form a process gas dissolved gas reagent.

[0046] This integrated system injects dissolved air reagents through a dissolved air injection unit. After the dissolved air reagent is prepared, the dissolved air injection pipeline is connected to the injection rod or injection well. After opening the dissolved air injection control valve, the liquid reagent containing compressed air is delivered to the injection rod or injection well and dispersed into the remediation stratum at a preset remediation depth. As the pressure gradually decreases, microbubbles are slowly released. The scouring, shearing, and lifting effects of the bubbles cause pollutants to desorb from the surface of soil particles and diffuse and migrate into groundwater, helping the remediation reagent to fully contact and mix with the pollutants. At the same time, the slowly released oxygen introduced into the ground promotes the formation of an aerobic underground environment for microbial remediation, achieving an in-situ microbial enhanced injection effect. During the injection process, the dissolved air reagent injection volume at a single point (well-type injection) or even a single depth (rod-type injection) is regulated and controlled by the dissolved air tank level and pipeline valves, and the system is moved to the next batch of injection points after the injection at the first injection point is completed.

[0047] This integrated system enables constant-pressure buffered individual injection of liquid agents through a dissolved air injection unit. After the liquid agent is prepared, the dosing pump of the agent preparation unit is started to deliver the liquid agent to the dissolved air tank. Following the constant-pressure injection procedure, valves are switched and the air compressor is started to introduce compressed air into the headspace of the dissolved air tank. Once the preset injection pressure is reached, the agent injection pipeline is connected to the injection rod or injection well. The agent injection control valve is opened, and the liquid agent is delivered to the injection rod or injection well. At the preset repair depth, it is then pressurized and dispersed into the repair formation, fulfilling the agent injection requirements for remediation technologies such as in-situ rinsing and in-situ chemical oxidation / reduction. During injection, the liquid agent injection volume at a single point (well-type injection) or even a single depth (rod-type injection) is controlled by adjusting the dissolved air tank level and pipeline valves. After injection at one point, the system moves to the next batch of injection points.

[0048] This integrated system enables constant-pressure buffered individual injection of compressed air via a dissolved air injection unit. After ensuring the liquid (if any) in the dissolved air tank is emptied, the valves are switched and the air compressor is started according to the constant-pressure compressed air injection procedure. Once the dissolved air tank reaches the preset air injection pressure value, the air injection pipeline is connected to the injection rod or injection well. The air injection control valve is opened, and the compressed air is delivered to the injection rod or injection well. At the preset repair depth, the compressed air is output under pressure and dispersed to the repair formation, meeting the air injection requirements for remediation technologies such as well blowout, groundwater aeration, and biological aeration. During the injection process, the air pressure in the dissolved air tank and the pipeline valves are used to jointly regulate and control the air injection volume and duration at individual points (well-type injection) or even individual depths (rod-type injection). After the injection at one point is completed, the system moves to the next batch of injection points.

[0049] This integrated system achieves atomized injection through a reagent preparation unit, a dissolved gas injection unit, and a venturi tube in the atomization mixing unit: After the liquid reagent is prepared, ensure that the liquid (if any) in the dissolved gas tank is emptied, then start the air compressor. After the compressed air reaches the preset atomization injection pressure value in the dissolved gas tank, connect the atomization injection pipeline to the injection rod or injection well, open the atomization injection control valve and the atomization suction control valve, and the compressed air moves at high speed through the narrow opening in the venturi tube and is suddenly depressurized, generating a negative pressure in a local area. The liquid reagent is drawn into the venturi tube by the siphon effect of another small pipe next to the air outlet due to the negative pressure and discharged. When the liquid reagent encounters the high-pressure airflow, it is impacted and broken into small aerosol particles and output with the airflow. It is transported to the injection rod or injection well through the atomization injection pipeline and dispersed into the remediation layer at the preset remediation depth. The faster the airflow speed and the higher the air pressure, the more aerosol is generated and the smaller the atomized particles are, which increases the ability of the liquid reagent to disperse in the remediation layer, especially to enter the small soil gaps in the vadose zone, and achieves in-situ injection to enhance the dispersion effect. During the injection process, the liquid level in the dissolving tank and the pipeline valves are used to jointly regulate and control the amount of atomized drug injected at a single point (well injection) or even a single depth (bar injection), and after the injection at the injection point is completed, it is moved to the next batch of injection points.

[0050] This integrated system achieves gas-liquid injection through a reagent preparation unit, a dissolved gas injection unit, and a venturi tube in the atomizing gas-mixing unit: After the liquid reagent is prepared, the dosing pump of the reagent preparation unit is started to deliver the liquid reagent to the dissolved gas tank. The air compressor is started, and after the compressed air reaches the preset gas-liquid injection pressure value at the top of the dissolved gas tank, the integrated system is switched to the pipeline valve state in the gas-liquid injection mode. This ensures the correct connection of the process gas supply pipeline. Subsequently, the gas-liquid injection pipeline is connected to the injection rod or injection well, and the gas-liquid injection control valve and the gas-liquid suction control valve are opened. The liquid agent is pressurized in a dissolved gas tank and delivered to a venturi tube, where it is ejected at high speed from the nozzle. A vacuum is created at the nozzle outlet, drawing in process gases (such as methane or hydrogen) through a mixing pipeline, which then thoroughly mixes the liquid agent with the process gases. This mixed-gas liquid agent is then transported through a mixing injection pipeline to the injection rod or injection well, and dispersed into the formation at a preset remediation depth. The combined action of the injected reducing remediation agent and the slowly released process gases creates an underground environment conducive to anaerobic remediation by microorganisms, achieving in-situ enhanced microbial injection. During injection, the liquid level in the dissolved gas tank and the valves in the process gas pipeline jointly regulate and control the amount of mixed-gas agent injected at a single point (well injection) or even a single depth (rod injection), and after injection at one point, it is moved to the next batch of injection points.

[0051] Example 2

[0052] A method for remediating soil groundwater using a dissolved air injection integrated system, the method comprising: a reagent injection mode, an air injection mode, a dissolved air injection mode, an atomized injection mode, and a mixed air injection mode.

[0053] Preferably, the drug injection mode includes:

[0054] Step 1.1: Move the mobile platform 30 to the vicinity of the injection point and connect it to an AC power source and a tap water source.

[0055] Step 1.2: Open the tap water valve and inject a certain amount of tap water into the tap water inlet 2 of the dissolving tank 1. Observe the liquid level of the dissolving tank 1 through the liquid level gauge 5 and control the amount of tap water added.

[0056] Step 1.3: Start the mixer 4 and add a certain amount of solid agent / concentrated agent to the solid agent / concentrated agent inlet 3 of the dissolving tank 1. After stirring for a certain period of time, a liquid agent that can be used for repair is formed.

[0057] Step 1.4: Open the drug inlet control valve 18 of the dissolved gas tank, start the dosing pump 7, and transfer the prepared liquid drug to the dissolved gas tank 10.

[0058] Step 1.5: Observe the liquid level of the dissolved gas tank 10 through the dissolved gas tank level gauge 11. After the preset amount of liquid agent is added, stop the dosing pump 7 and close the dissolved gas tank inlet control valve 18.

[0059] Step 1.6: Open the gas-liquid balance valve 21 on the top of the dissolved gas tank on the pipeline connecting the air compressor 8 and the dissolved gas tank 10.

[0060] Step 1.7: Start the air compressor 8. Compressed air is pressurized into the dissolved gas tank 10 through the gas-liquid balance valve 21 at the top of the dissolved gas tank. After a certain period of time, the liquid agent reaches a pressure value that can be used for repair.

[0061] Step 1.8: Connect the drug injection pipeline to the injection rod or injection well via the dissolved gas injection pipeline interface 23 through the injection hose.

[0062] Step 1.9: Open the dissolved gas injection control valve 22. Under the constant pressure maintained by the air compressor 8 in the dissolved gas tank 10, the liquid agent is distributed to the repair formation through the injection rod or injection well at the preset repair depth.

[0063] Step 1.10: Observe the liquid level of the dissolved gas tank 10 through the dissolved gas tank level gauge 11. After the preset amount of reagent is injected, close the dissolved gas injection control valve 22.

[0064] Step 1.11: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 1.9 to 1.10 until all designed injection depths at that injection point have been injected with the drug. Then connect the drug injection line to the next injection point and repeat steps 1.8 to 1.11 (repeat steps 1.2 to 1.11 when the drug is used up) until all designed injection points have been injected with the drug. When using a well-type injection, connect the drug injection line to the next injection point and repeat steps 1.8 to 1.11 (repeat steps 1.2 to 1.11 when the drug is used up) until all designed injection points have been injected with the drug.

[0065] Step 1.12: After completing all injection operations, close the dissolved gas injection control valve 22, shut down the air compressor 8, release the pressure in the dissolved gas tank 10 through the dissolved gas tank exhaust valve 14, and drain the excess liquid agent in the drug dissolving tank 5 and the dissolved gas tank 10 through the drug dissolving tank exhaust valve 6 and the dissolved gas tank exhaust valve 15, respectively.

[0066] Example 3

[0067] A method for remediating soil groundwater using a dissolved air injection integrated system, the method comprising: a reagent injection mode, an air injection mode, a dissolved air injection mode, an atomized injection mode, and a mixed air injection mode.

[0068] Preferably, the air injection mode includes:

[0069] Step 2.1: Move the mobile platform 30 to the vicinity of the injection point and connect it to an AC power source.

[0070] Step 2.2: Open the gas-liquid balance valve 21 on the top of the dissolved gas tank on the pipeline connecting the air compressor 8 and the dissolved gas tank 10.

[0071] Step 2.3: After ensuring that the liquid (if any) in the dissolved air tank 10 is emptied, start the air compressor 8. After running for a certain period of time, the compressed air in the dissolved air tank 10 will reach a pressure value suitable for repair.

[0072] Step 2.4: Connect the air injection pipe to the injection rod or injection well via the dissolved gas injection pipe interface 23 through the injection hose.

[0073] Step 2.5: Open the dissolved gas injection control valve 22. Compressed air is then distributed under pressure to the formation at the preset repair depth through the injection rod or injection well.

[0074] Step 2.6: Observe the pressure value of compressed air in dissolved air tank 10 through dissolved air tank pressure gauge 12. After the target air injection time under the preset pressure is reached, close dissolved air injection control valve 22.

[0075] Step 2.7: When using a bar-type injection, move the injection bar to the next injection depth and repeat steps 2.5 to 2.6 until air injection is completed at all designed injection depths for that injection point. Then connect the air injection line to the next injection point and repeat steps 2.4 to 2.7 until air injection is completed at all designed injection points. When using a well-type injection, connect the air injection line to the next injection point and repeat steps 4 to 7 until air injection is completed at all designed injection points.

[0076] Step 2.8: After completing all injection operations, close the dissolved gas injection control valve 22, shut down the air compressor 8, and release the pressure in the dissolved gas tank 10 through the dissolved gas tank exhaust valve 14.

[0077] Example 4

[0078] A method for remediating soil groundwater using a dissolved air injection integrated system, the method comprising: a reagent injection mode, an air injection mode, a dissolved air injection mode, an atomized injection mode, and a mixed air injection mode.

[0079] Preferably, the dissolved gas injection mode includes:

[0080] Step 3.1: Move the mobile platform 30 to the vicinity of the injection point and connect it to an AC power source and a tap water source.

[0081] Step 3.2: Open the tap water valve and inject a certain amount of tap water into the tap water inlet 2 of the dissolving tank 1. Observe the liquid level of the dissolving tank 1 through the liquid level gauge 5 and control the amount of tap water added.

[0082] Step 3.3: Start the mixer 4 and add a certain amount of solid agent / concentrated agent to the solid agent / concentrated agent inlet 3 of the dissolving tank 1. After stirring for a certain period of time, a liquid agent that can be used for repair is formed.

[0083] Step 3.4: Open the drug inlet control valve 18 of the dissolved gas tank, start the dosing pump 7, and transfer the prepared liquid drug to the dissolved gas tank 10.

[0084] Step 3.5: Observe the liquid level of dissolved gas tank 10 through dissolved gas tank level gauge 11. After the preset amount of liquid agent added is reached, stop the dosing pump 7 and close the dissolved gas tank inlet control valve 18.

[0085] Step 3.6: Open the air inlet control valve 19 at the bottom of the dissolved air tank on the pipeline connecting the air compressor 8 and the dissolved air tank 10.

[0086] Step 3.7: Start the air compressor 8. Compressed air is dispersed into the liquid agent through the dissolved air cloth head 20 at the bottom of the dissolved air tank. After a certain period of time, the dissolved air agent reaches the pressure value that can be used for repair. Close the air inlet control valve 19 at the bottom of the dissolved air tank and open the gas-liquid balance valve 21 at the top of the dissolved air tank to maintain the gas-liquid balance in the dissolved air tank 10 and the agent injection pressure.

[0087] Step 3.8: Connect the dissolved gas injection pipeline to the injection rod or injection well via the injection hose through the dissolved gas injection pipeline interface 23.

[0088] Step 3.9: Open the dissolved gas injection pipeline interface 22. The dissolved gas agent is distributed under pressure to the formation to be repaired through the injection rod or injection well at the preset repair depth.

[0089] Step 3.10: Observe the liquid level of the dissolved gas tank 10 through the dissolved gas tank level gauge 11. After the preset dissolved gas agent injection amount is reached, close the dissolved gas injection pipeline interface 22.

[0090] Step 3.11: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 3.9 to 3.10 until dissolved gas injection is completed at all designed injection depths for that injection point. Then connect the dissolved gas injection pipeline to the next injection point and repeat steps 3.8 to 3.11 (repeat steps 3.2 to 3.11 when the reagent is used up) until dissolved gas injection is completed at all designed injection points. When using a well-type injection, connect the dissolved gas injection pipeline to the next injection point and repeat steps 3.8 to 3.11 (repeat steps 3.2 to 3.11 when the reagent is used up) until dissolved gas injection is completed at all designed injection points.

[0091] Step 12: After completing all injection operations, close the dissolved gas injection control valve 22, shut down the air compressor 8, release the pressure in the dissolved gas tank 10 through the dissolved gas tank exhaust valve 14, and drain the excess liquid agents in the drug dissolving tank 5 and the dissolved gas tank 10 through the drug dissolving tank exhaust valve 6 and the dissolved gas tank exhaust valve 15, respectively.

[0092] Example 5

[0093] A method for remediating soil groundwater using a dissolved air injection integrated system, the method comprising: a reagent injection mode, an air injection mode, a dissolved air injection mode, an atomized injection mode, and a mixed air injection mode.

[0094] Preferably, the atomization injection mode includes:

[0095] Step 4.1: Move the mobile platform 30 to the vicinity of the injection point and connect it to the AC power supply and tap water source.

[0096] Step 4.2: Open the tap water valve and inject a certain amount of tap water into the tap water inlet 2 of the dissolving tank 1. Observe the liquid level of the dissolving tank 1 through the liquid level gauge 5 and control the amount of tap water added.

[0097] Step 4.3: Start the mixer 4 and add a certain amount of solid agent / concentrated agent to the solid agent / concentrated agent inlet 3 of the dissolving tank 1. After stirring for a certain period of time, a liquid agent that can be used for repair is formed.

[0098] Step 4.4: After ensuring that the liquid (if any) in the dissolved air tank 10 is emptied, open the gas-liquid balance valve 21 on the top of the dissolved air tank on the pipeline connecting the air compressor 8 and the dissolved air tank 10, start the air compressor 8, and after running for a certain period of time, the compressed air in the dissolved air tank 10 reaches a pressure value suitable for repair.

[0099] Step 4.5: Connect the atomizing injection pipeline to the injection rod or injection well via the injection hose through the Venturi tube outlet control valve 27.

[0100] Step 4.6: Open the Venturi tube outlet control valve 27, the Venturi tube inlet control valve 24, and the atomization suction control valve 25. The compressed air moves at high speed through the narrow opening inside the Venturi tube 26 and is suddenly depressurized, generating a negative pressure in a local area. The liquid agent drawn in by the negative pressure through the small tube connected to the atomization suction control valve 25 next to the airflow outlet is discharged. When the liquid agent encounters the high-pressure airflow, it is impacted and broken into small aerosol particles and output with the airflow. It is then distributed under pressure to the repaired stratum through the injection rod or injection well at the preset repair depth and enters the small soil gaps in the vadose zone.

[0101] Step 4.7: Observe the liquid level of the dissolving tank 6 through the liquid level gauge 5. After the preset amount of atomized drug is injected, close the Venturi tube outlet control valve 27, the Venturi tube inlet control valve 24 and the atomization inhalation control valve 25.

[0102] Step 4.8: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 4.6 to 4.7 until all designed injection depths at that injection point have been nebulized. Then connect the nebulization injection tubing to the next injection point and repeat steps 4.5 to 4.8 (repeat steps 4.2 to 4.8 when the reagent runs out) until all designed injection points have been nebulized. When using a well-type injection, connect the nebulization injection tubing to the next injection point and repeat steps 4.5 to 4.8 (repeat steps 4.2 to 4.8 when the reagent runs out) until all designed injection points have been dissolved in gas.

[0103] Step 9: After completing all injection operations, close the Venturi tube outlet control valve 27, the Venturi tube inlet control valve 24, and the atomizing suction control valve 25. Turn off the air compressor 8, release the pressure in the dissolved gas tank 10 through the dissolved gas tank exhaust valve 14, and drain the excess liquid agent in the dissolved drug tank 5 through the dissolved drug tank venting valve 6.

[0104] Example 6

[0105] A method for remediating soil groundwater using a dissolved air injection integrated system, the method comprising: a reagent injection mode, an air injection mode, a dissolved air injection mode, an atomized injection mode, and a mixed air injection mode.

[0106] Preferably, the gas-mixed injection mode includes:

[0107] Step 5.1: Move the mobile platform 30 to the vicinity of the injection point and connect it to the AC power supply and tap water source.

[0108] Step 5.2: Open the tap water valve and inject a certain amount of tap water into the tap water inlet 2 of the dissolving tank 1. Observe the liquid level of the dissolving tank 1 through the liquid level gauge 5 and control the amount of tap water added.

[0109] Step 5.3: Start the mixer 4 and add a certain amount of solid agent / concentrated agent to the solid agent / concentrated agent inlet 3 of the dissolving tank 1. After stirring for a certain period of time, a liquid agent that can be used for repair is formed.

[0110] Step 5.4: Open the drug inlet control valve 18 of the dissolved gas tank, start the dosing pump 7, and transfer the prepared liquid drug to the dissolved gas tank 10.

[0111] Step 5.5: Observe the liquid level of dissolved gas tank 10 through dissolved gas tank level gauge 11. After the preset amount of liquid agent added is reached, stop the dosing pump 7 and close the dissolved gas tank inlet control valve 18.

[0112] Step 5.6: Open the gas-liquid balance valve 21 on the top of the dissolved gas tank on the pipeline connecting the air compressor 8 and the dissolved gas tank 10.

[0113] Step 5.7: Start the air compressor 8. Compressed air is pressurized into the dissolved gas tank 10 through the gas-liquid balance valve 21 at the top of the dissolved gas tank. After a certain period of time, the liquid agent reaches a pressure value that can be used for repair.

[0114] Step 5.8: Connect the gas-mixing injection pipeline to the injection rod or injection well via the injection hose through the Venturi tube outlet control valve 27.

[0115] Step 5.9: Open the Venturi tube outlet control valve 27, the Venturi tube inlet control valve 24, and the gas mixing intake control valve 28. The liquid agent is pressurized by the dissolved gas tank 10 and sent to the Venturi tube 26 and sprayed out from the nozzle inside the tube at a very high speed. By creating a vacuum in the nozzle outlet area, the process gas (such as methane, hydrogen, etc.) is drawn in by the gas mixing pipeline connected to the gas mixing intake control valve 28 next to the nozzle outlet and fully mixed with the liquid agent. The liquid agent mixed with the process gas is then discharged under pressure to the repair formation through the injection rod or injection well at the preset repair depth.

[0116] Step 5.10: Observe the liquid level of dissolved gas tank 10 through dissolved gas tank level gauge 11. After the preset dissolved gas agent injection amount is reached, close the Venturi tube outlet control valve 27, Venturi tube inlet control valve 24 and mixed gas intake control valve 28.

[0117] Step 5.11: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 5.9 to 5.10 until all designed injection depths at that injection point have been filled with gas mixture. Then connect the gas mixture injection pipe to the next injection point and repeat steps 5.8 to 5.11 (repeat steps 5.2 to 5.11 when the reagent is used up) until all designed injection points have been filled with atomized gas. When using a well-type injection, connect the gas mixture injection pipe to the next injection point and repeat steps 5.8 to 5.11 (repeat steps 5.2 to 5.11 when the reagent is used up) until all designed injection points have been filled with dissolved gas.

[0118] Step 5.12: After completing all injection operations, close the Venturi tube outlet control valve 27, the Venturi tube inlet control valve 24, and the mixed air intake control valve 28. Turn off the air compressor 8, release the pressure in the dissolved gas tank 10 through the dissolved gas tank exhaust valve 14, and drain the excess liquid agent in the drug dissolving tank 5 and the dissolved gas tank 10 through the drug dissolving tank exhaust valve 6 and the dissolved gas tank exhaust valve 15, respectively.

[0119] The present invention provides a method and system for remediating soil and groundwater using an integrated dissolved gas injection system. The dissolved gas injection system, which includes components such as a reagent preparation unit, a dissolved gas injection unit, and an atomization mixing unit, is integrated on a mobile platform. In use, the integrated injection system is moved to the vicinity of the injection point, and an injection rod / injection well matching the remediation depth is connected to the pipeline of the integrated injection system. It can flexibly select the dissolved gas injection process of pressurizing dissolved gas in liquid reagent, or the atomization injection and mixed gas injection processes of dispersing and mixing liquid reagent with air or other process gases in different forms, as well as the reagent injection and air injection processes that improve the traditional liquid and gas injection methods to form a constant pressure buffer. It is suitable for the remediation of soil and groundwater pollution at different depths such as the vadose zone and saturation zone. The method involved in this patent employs an integrated system to achieve the injection of liquid and gas individually or in combination to meet the process requirements of soil and groundwater remediation scenarios. During the injection of remediation agents into contaminated strata, the gas-water flushing formed by controlling the injection of liquid and gas individually or in combination enhances the desorption of pollutants and the dispersion and mixing of agent materials. By introducing process gases such as air (oxygen), methane, or hydrogen, the in-situ microbial remediation environment is improved, thereby increasing remediation efficiency, enhancing remediation effect, and achieving long-lasting, low-consumption microbial enhanced green remediation.

[0120] This invention provides a method and system for in-situ remediation of soil and groundwater pollution using a mobile dissolved gas injection integrated system. Addressing the need for long-term, low-consumption, and green remediation of soil and groundwater in organically contaminated sites, this invention develops a novel technology friendly to in-situ microbial enhanced remediation, building upon traditional physical and chemical remediation techniques. It solves the problems of effective dispersion of bioremediation functional materials in in-situ contaminated strata and continuous supply of oxygen or other process gases, forming a low-cost, high-efficiency, environmentally friendly, and easily integrated microbial enhanced remediation technology system suitable for combination with other engineering technologies and widespread application in the in-situ remediation of soil and groundwater in organically contaminated sites, thereby achieving better comprehensive social, economic, and environmental benefits.

[0121] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. An integrated dissolved air injection system for remediating soil groundwater, characterized in that, The dissolved gas injection integrated system includes: a drug preparation unit, a dissolved gas injection unit, an atomization and mixing unit, and an auxiliary unit; The drug preparation unit includes a dissolving tank and a dosing pump, with a stirrer installed inside the dissolving tank; the dissolved gas injection unit includes an air compressor and a dissolved gas tank; the atomizing gas mixing unit includes a venturi tube, a liquid-gas connection pipe, and a switching valve; the auxiliary unit includes an electrical control cabinet and a mobile platform. The electrical control cabinets for the drug preparation unit, dissolved gas injection unit, atomized gas mixing unit, and auxiliary unit are all integrated on a mobile platform. The integrated system includes a drug preparation unit comprising a dissolving tank, a dosing pump, and a mixer. The dissolving tank is equipped with a tap water inlet, a solid drug / drug concentrate dosing inlet, a dissolving tank level gauge, and a dissolving tank vent valve. The dissolved gas injection unit comprises an air compressor, a dissolved gas tank, and supporting components for the dissolved gas injection process, including a dissolved gas tank process gas inlet, a dissolved gas tank drug inlet control valve, a dissolved gas tank bottom air inlet control valve, a dissolved gas distribution head at the bottom of the dissolved gas tank, a dissolved gas tank top gas-liquid balance valve, a dissolved gas injection control valve, and a dissolved gas injection pipeline interface. The dissolved gas tank is equipped with a dissolved gas tank level gauge, a dissolved gas tank pressure gauge, a dissolved gas tank pressure relief valve, a dissolved gas tank exhaust valve, a dissolved gas tank vent valve, and a dissolved gas tank outlet back pressure valve. The atomization and mixing unit comprises a venturi tube, and supporting components for the atomization and mixing injection process, including a venturi tube inlet control valve, an atomization suction control valve, a mixing suction control valve, and a venturi tube outlet control valve located at the injection pipeline interface. The integrated system described above uses a drug preparation unit to prepare liquid drugs: solid drugs or liquid drug concentrates are manually added into the dissolving tank according to the preparation ratio, tap water is added from the tap water inlet, and the mixture is stirred by a mixer to form a liquid drug for repair. The integrated system described above uses a dissolved gas injection unit to prepare dissolved gas agents: after the liquid agent is prepared, the dosing pump of the agent preparation unit is started to deliver the liquid agent to the dissolved gas tank. The valves are switched according to the dissolved gas program and the air compressor is started to introduce compressed air into the dissolved gas tank and disperse it into the liquid agent through the air distribution head to fully dissolve it and form a supersaturated state. After the dissolved gas tank reaches the preset dissolved gas injection pressure value, a dissolved gas agent for repair is formed. The integrated system described above uses a dissolved gas injection unit to inject dissolved gas agents: after the dissolved gas agents are prepared, the dissolved gas injection pipeline is connected to the injection rod or injection well. After the dissolved gas injection control valve is opened, the liquid agent containing compressed air is delivered to the injection rod or injection well for injection, and is dispersed to the repair formation at a preset repair depth. During the injection process, the amount of dissolved gas agent injected at a single point and a single depth is adjusted and controlled by the liquid level in the dissolved gas tank and the pipeline valves. After the injection at the injection point is completed, the system moves to the next batch of injection points. The integrated system described above achieves constant-pressure buffered individual injection of liquid agents through a dissolved gas injection unit: After the liquid agent is prepared, the dosing pump of the agent preparation unit is started to deliver the liquid agent to the dissolved gas tank. The valves are switched and the air compressor is started according to the constant-pressure injection procedure to introduce compressed air into the headspace of the dissolved gas tank. After reaching the preset agent injection pressure value, the agent injection pipeline is connected to the injection rod or injection well, the agent injection control valve is opened, and the liquid agent is delivered to the injection rod or injection well for injection. It is then output under pressure at the preset repair depth and dispersed to the repair formation. During the injection process, the liquid agent injection volume at a single point and a single depth is controlled by adjusting the liquid level in the dissolved gas tank and the pipeline valves. After the injection at the injection point is completed, it is moved to the next batch of injection points. The integrated system described above achieves constant-pressure buffered individual injection of compressed air through a dissolved air injection unit: After ensuring that the liquid in the dissolved air tank is emptied, the valves are switched and the air compressor is started according to the constant-pressure compressed air injection procedure. After the compressed air in the dissolved air tank reaches the preset air injection pressure value, the air injection pipeline is connected to the injection rod or injection well, the air injection control valve is opened, and the compressed air is delivered to the injection rod or injection well for injection. The compressed air is then output under pressure at the preset repair depth and dispersed to the repair formation. During the injection process, the air injection volume and injection time at a single point and a single depth are adjusted and controlled by the air pressure in the dissolved air tank and the pipeline valves. After the injection at the injection point is completed, the system moves to the next batch of injection points.

2. The dissolved air injection integrated system for remediating soil groundwater according to claim 1, characterized in that, The integrated system achieves atomized injection through a drug preparation unit, a dissolved gas injection unit, and a venturi tube in the atomization mixing unit: After the liquid drug is prepared, the liquid in the dissolved gas tank is emptied, and then the air compressor is started. After the compressed air reaches the preset atomization injection pressure value in the dissolved gas tank, the atomization injection pipeline is connected to the injection rod or injection well. The atomization injection control valve and the atomization suction control valve are opened. The compressed air moves at high speed through the narrow opening in the venturi tube and is suddenly depressurized, generating a negative pressure in a local area. The liquid drug is drawn into the venturi tube by the siphon effect of another small pipe next to the air outlet due to the negative pressure and discharged. When the liquid drug encounters the high-pressure airflow, it is impacted and broken into small aerosol particles and output with the airflow. It is transported to the injection rod or injection well through the atomization injection pipeline for injection and is dispersed to the repair formation at the preset repair depth. During the injection process, the liquid level in the drug preparation tank and the pipeline valves are used to adjust and control the atomized drug injection volume at a single point and a single depth, and after the injection at the injection point is completed, it is moved to the next batch of injection points. The integrated system, through a reagent preparation unit and a dissolved gas injection unit, combined with a venturi tube in the atomizing gas mixing unit, achieves gas-mixing injection: After the liquid reagent is prepared, the dosing pump of the reagent preparation unit is started to deliver the liquid reagent to the dissolved gas tank. The air compressor is started, and after the compressed air reaches the preset gas-mixing injection pressure value at the top of the dissolved gas tank, the integrated system is switched to the pipeline valve state in the gas-mixing injection mode to ensure that the process gas supply pipeline is correctly connected. Subsequently, the gas-mixing injection pipeline is connected to the injection rod or injection well, and the gas-mixing injection control valve and the gas-mixing suction control valve are opened. The liquid reagent is pressurized by the dissolved gas tank and sent to the Venturi tube, where it is ejected from the nozzle at a high speed. A vacuum is created in the nozzle outlet area, which draws in the process gas through the mixing pipeline and mixes it thoroughly with the liquid reagent. The liquid reagent mixed with the process gas is then transported to the injection rod or injection well through the mixed gas injection pipeline for injection. It is then output and dispersed to the formation to be repaired at the preset repair depth. During the injection process, the amount of mixed gas reagent injected at a single point and a single depth is adjusted and controlled by the liquid level in the dissolved gas tank and the valves in the process gas pipeline. After the injection at the injection point is completed, the reagent is moved to the next batch of injection points.

3. A method for remediating soil groundwater using the dissolved air injection integrated system as described in claim 1 or 2, characterized in that, The method includes: drug injection mode, air injection mode, dissolved gas injection mode, atomized injection mode, and mixed gas injection mode; The drug injection mode includes: Step 1.1: Move the mobile platform to the vicinity of the injection point and connect it to AC power and tap water. Step 1.2: Open the tap water valve and inject tap water into the tap water inlet of the dissolving tank. Observe the liquid level in the dissolving tank through the liquid level gauge and control the amount of tap water added. Step 1.3: Start the mixer and add solid agent / concentrated agent to the solid agent / concentrated agent inlet of the dissolving tank. After stirring, a liquid agent for repair is formed. Step 1.4: Open the inlet control valve of the dissolved gas tank, start the dosing pump, and transfer the prepared liquid medicine to the dissolved gas tank; Step 1.5: Observe the liquid level in the dissolved gas tank through the liquid level gauge. After the preset amount of liquid agent to be added is reached, stop the dosing pump and close the dosing control valve of the dissolved gas tank. Step 1.6: Open the gas-liquid balance valve on the top of the dissolved gas tank on the pipeline connecting the air compressor and the dissolved gas tank; Step 1.7: Start the air compressor. Compressed air is pressurized into the dissolved gas tank through the gas-liquid balance valve at the top of the dissolved gas tank until the liquid agent reaches the pressure value required for repair. Step 1.8: Connect the drug injection pipeline to the injection rod or injection well via the dissolved gas injection pipeline interface using an injection hose; Step 1.9: Open the dissolved gas injection control valve. Under the constant pressure maintained by the air compressor in the dissolved gas tank, the liquid agent is distributed under pressure to the repair formation through the injection rod or injection well at the preset repair depth. Step 1.10: Observe the liquid level of the dissolved gas tank through the dissolved gas tank level gauge. After the preset amount of reagent is injected, close the dissolved gas injection control valve. Step 1.11: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 1.9 to 1.10 until all designed injection depths at that injection point have been injected with the drug. Then connect the drug injection line to the next injection point and repeat steps 1.8 to 1.

11. When the drug is used up, repeat steps 1.2 to 1.11 until all designed injection points have been injected with the drug. When using a well-type injection, connect the drug injection line to the next injection point and repeat steps 1.8 to 1.

11. When the drug is used up, repeat steps 1.2 to 1.11 until all designed injection points have been injected with the drug. Step 1.12: After completing all injection operations, close the dissolved gas injection control valve, shut down the air compressor, release the pressure in the dissolved gas tank through the dissolved gas tank exhaust valve, and empty the excess liquid agent in the drug dissolving tank and the dissolved gas tank through the drug dissolving tank exhaust valve and the dissolved gas tank exhaust valve, respectively.

4. The method for remediating soil groundwater using a dissolved air injection integrated system according to claim 3, characterized in that, The air injection mode in the method includes: Step 2.1: Move the mobile platform to the vicinity of the injection point and connect it to an AC power source; Step 2.2: Open the gas-liquid balance valve on the top of the dissolved gas tank on the pipeline connecting the air compressor and the dissolved gas tank; Step 2.3: After ensuring that the liquid in the dissolved air tank is emptied, start the air compressor and run it until the compressed air in the dissolved air tank reaches the pressure value required for repair. Step 2.4: Connect the air injection pipe to the injection rod or injection well via the dissolved gas injection pipe interface using an injection hose; Step 2.5: Open the dissolved gas injection control valve, and the compressed air is output under pressure and dispersed into the repair formation through the injection rod or injection well at the preset repair depth; Step 2.6: Observe the pressure value of compressed air in the dissolved air tank through the pressure gauge of the dissolved air tank. After the target air injection time under the preset pressure is reached, close the dissolved air injection control valve. Step 2.7: When using a bar-type injection, move the injection bar to the next injection depth and repeat steps 2.5 to 2.6 until air injection is completed at all designed injection depths for that injection point. Then connect the air injection line to the next injection point and repeat steps 2.4 to 2.7 until air injection is completed at all designed injection points. When using a well-type injection, connect the air injection line to the next injection point and repeat steps 2.4 to 2.7 until air injection is completed at all designed injection points. Step 2.8: After completing all injection operations, close the dissolved gas injection control valve, shut down the air compressor, and release the pressure in the dissolved gas tank through the dissolved gas tank exhaust valve.

5. The method for remediating soil groundwater using a dissolved air injection integrated system according to claim 3, characterized in that, The dissolved gas injection mode in the method includes: Step 3.1: Move the mobile platform to the vicinity of the injection point and connect it to AC power and tap water. Step 3.2: Open the tap water valve and inject tap water into the tap water inlet of the dissolving tank. Observe the liquid level in the dissolving tank through the liquid level gauge and control the amount of tap water added. Step 3.3: Start the mixer and add solid agent / concentrated agent into the solid agent / concentrated agent inlet of the dissolving tank. After stirring, a liquid agent for repair is formed. Step 3.4: Open the inlet control valve of the dissolved gas tank, start the dosing pump, and transfer the prepared liquid medicine to the dissolved gas tank; Step 3.5: Observe the liquid level in the dissolved gas tank through the liquid level gauge. After the preset amount of liquid agent to be added is reached, stop the dosing pump and close the dosing control valve of the dissolved gas tank. Step 3.6: Open the air inlet control valve at the bottom of the dissolved air tank on the pipeline connecting the air compressor and the dissolved air tank; Step 3.7: Start the air compressor. Compressed air is dispersed into the liquid agent through the dissolved air cloth head at the bottom of the dissolved air tank until the dissolved air agent reaches the pressure value for repair. Then, close the air inlet control valve at the bottom of the dissolved air tank and open the gas-liquid balance valve at the top of the dissolved air tank to maintain the gas-liquid balance in the dissolved air tank and the agent injection pressure. Step 3.8: Connect the dissolved gas injection pipeline to the injection rod or injection well via the dissolved gas injection pipeline interface using an injection hose; Step 3.9: Open the dissolved gas injection pipeline interface, and the dissolved gas agent is output under pressure and dispersed into the formation to be repaired through the injection rod or injection well at the preset repair depth; Step 3.10: Observe the liquid level of the dissolved gas tank through the dissolved gas tank level gauge. After the preset amount of dissolved gas agent is injected, close the dissolved gas injection pipeline interface. Step 3.11: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 3.9 to 3.10 until dissolved gas injection is completed at all designed injection depths for that injection point. Then connect the dissolved gas injection pipeline to the next injection point and repeat steps 3.8 to 3.

11. When the reagent is used up, repeat steps 3.2 to 3.11 until dissolved gas injection is completed at all designed injection points. When using a well-type injection, connect the dissolved gas injection pipeline to the next injection point and repeat steps 3.8 to 3.

11. When the reagent is used up, repeat steps 3.2 to 3.11 until dissolved gas injection is completed at all designed injection points. Step 3.12: After completing all injection operations, close the dissolved gas injection control valve, shut down the air compressor, release the pressure in the dissolved gas tank through the dissolved gas tank exhaust valve, and empty the excess liquid agent in the drug dissolving tank and the dissolved gas tank through the drug dissolving tank exhaust valve and the dissolved gas tank exhaust valve, respectively.

6. The method for remediating soil groundwater using a dissolved air injection integrated system according to claim 3, characterized in that, The atomization injection mode described in the method includes: Step 4.1: Move the mobile platform to the vicinity of the injection point and connect it to AC power and tap water. Step 4.2: Open the tap water valve and inject tap water into the tap water inlet of the dissolving tank. Observe the liquid level in the dissolving tank through the liquid level gauge and control the amount of tap water added. Step 4.3: Start the mixer and add solid agent / concentrated agent into the solid agent / concentrated agent inlet of the dissolving tank. After stirring, a liquid agent for repair is formed. Step 4.4: After ensuring that the liquid in the dissolved air tank is emptied, open the gas-liquid balance valve on the top of the dissolved air tank on the pipeline connecting the air compressor and the dissolved air tank, start the air compressor, and run it until the compressed air in the dissolved air tank reaches the pressure value required for repair. Step 4.5: Connect the atomizing injection pipeline to the injection rod or injection well via the injection hose through the Venturi tube outlet control valve; Step 4.6: Open the Venturi tube outlet control valve, Venturi tube inlet control valve, and atomization suction control valve. The compressed air moves at high speed through the narrow opening inside the Venturi tube and is suddenly depressurized, generating a negative pressure in a local area. The liquid agent drawn in by the other small tube connected to the atomization suction control valve next to the air outlet is discharged due to the siphon effect of the negative pressure. When the liquid agent encounters the high-pressure airflow, it is impacted and broken into small aerosol particles and output with the airflow. It is then dispersed into the repaired stratum under pressure through the injection rod or injection well at the preset repair depth and enters the small soil gaps in the vadose zone. Step 4.7: Observe the liquid level of the dissolving tank through the liquid level gauge. After the preset amount of atomized drug is injected, close the Venturi tube outlet control valve, the Venturi tube inlet control valve, and the atomization inhalation control valve. Step 4.8: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 4.6 to 4.7 until all designed injection depths at that injection point have been nebulized. Then connect the nebulization injection tubing to the next injection point and repeat steps 4.5 to 4.

8. When the reagent is used up, repeat steps 4.2 to 4.8 until all designed injection points have been nebulized. When using a well-type injection, connect the nebulization injection tubing to the next injection point and repeat steps 4.5 to 4.

8. When the reagent is used up, repeat steps 4.2 to 4.8 until all designed injection points have been dissolved in gas. Step 4.9: After completing all injection operations, close the Venturi tube outlet control valve, Venturi tube inlet control valve, and atomizing suction control valve, shut down the air compressor, release the pressure in the dissolved gas tank through the dissolved gas tank exhaust valve, and drain the excess liquid agent in the dissolved gas tank through the dissolved gas tank vent valve.

7. The method for remediating soil groundwater using a dissolved air injection integrated system according to claim 3, characterized in that, The method described includes a gas-mixed injection mode comprising: Step 5.1: Move the mobile platform to the vicinity of the injection point and connect it to AC power and tap water. Step 5.2: Open the tap water valve and inject tap water into the tap water inlet of the dissolving tank. Observe the liquid level of the dissolving tank through the liquid level gauge and control the amount of tap water added. Step 5.3: Start the mixer and add solid agent / concentrated agent into the solid agent / concentrated agent inlet of the dissolving tank. After stirring, a liquid agent for repair is formed. Step 5.4: Open the inlet control valve of the dissolved gas tank, start the dosing pump, and transfer the prepared liquid medicine to the dissolved gas tank; Step 5.5: Observe the liquid level in the dissolved gas tank through the liquid level gauge. After the preset amount of liquid agent to be added is reached, stop the dosing pump and close the dosing control valve of the dissolved gas tank. Step 5.6: Open the gas-liquid balance valve on the top of the dissolved gas tank on the pipeline connecting the air compressor and the dissolved gas tank; Step 5.7: Start the air compressor. Compressed air is pressurized into the dissolved gas tank through the gas-liquid balance valve at the top of the dissolved gas tank until the liquid agent reaches the pressure value required for repair. Step 5.8: Connect the gas-mixing injection pipeline to the injection rod or injection well via the injection hose through the Venturi tube outlet control valve; Step 5.9: Open the Venturi tube outlet control valve, Venturi tube inlet control valve and gas mixing intake control valve. The liquid agent is pressurized by the dissolved gas tank and sent to the Venturi tube. It is then sprayed out from the nozzle inside the tube at high speed. By creating a vacuum in the nozzle outlet area, the process gas is drawn in by the gas mixing pipeline connected to the gas mixing intake control valve next to the nozzle outlet and fully mixed with the liquid agent. The liquid agent mixed with the process gas is then discharged under pressure and dispersed into the repair formation through the injection rod or injection well at the preset repair depth. Step 5.10: Observe the liquid level of the dissolved gas tank through the dissolved gas tank level gauge. After the preset dissolved gas agent injection volume is reached, close the Venturi tube outlet control valve, the Venturi tube inlet control valve, and the mixed gas intake control valve. Step 5.11: When using a rod-type injection, move the injection rod to the next injection depth and repeat steps 5.9 to 5.10 until all designed injection depths at that injection point have been filled with gas mixture. Then connect the gas mixture injection pipe to the next injection point and repeat steps 5.8 to 5.

11. When the reagent is used up, repeat steps 5.2 to 5.11 until all designed injection points have been filled with atomized gas. When using a well-type injection, connect the gas mixture injection pipe to the next injection point and repeat steps 5.8 to 5.

11. When the reagent is used up, repeat steps 5.2 to 5.11 until all designed injection points have been filled with dissolved gas. Step 5.12: After completing all injection operations, close the Venturi tube outlet control valve, Venturi tube inlet control valve, and mixed gas intake control valve. Turn off the air compressor, release the pressure in the dissolved gas tank through the dissolved gas tank exhaust valve, and empty the excess liquid agent in the dissolved drug tank and the dissolved gas tank through the dissolved drug tank vent valve and the dissolved gas tank vent valve, respectively.

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