In-situ multiphase integrated injection well device and in-situ multiphase injection method for soil remediation

Abstract

The present invention discloses an in-situ multiphase integrated injection well device and an in-situ multiphase injection method for soil remediation, comprising: a well pipe provided with an air inlet, multiple gas injection ports, and multiple liquid injection holes, and the pore wall of the liquid injection holes is arc-shaped; a supporting core column coaxially arranged inside the well pipe, with multiple ribs formed on its side corresponding to the positions of the liquid injection holes and a groundwater detection instrument installed thereon; a liquid injection mechanism including a movable ring plate and multiple spokes, the movable ring plate is movably sleeved outside the supporting core column, the movable ring plate is provided with multiple radial holes, the middle parts of the spokes are slidably arranged in the radial holes, one end of each spoke is installed with an electric roller, the side of the supporting core column is supported on the electric roller, and the end face of the other end of each spoke is attached to the inner side of the pipe wall of the well pipe and a nozzle is installed thereon. The present invention solves the problems that the existing in-situ injection wells cannot ensure the simultaneous injection of gas phase and liquid phase, and the injection pressure of liquid agents is insufficient in low-permeability formations and is prone to infiltration from preferential channels in high-permeability formations.

Description

Technical Field

[0001] The present invention relates to the technical field of soil remediation, and particularly relates to an in-situ multiphase integrated injection well device and an in-situ multiphase injection method for soil remediation. Background Art

[0002] The in-situ soil remediation technology refers to the technology of directly remediating contaminated soil at the contaminated site without excavation, which has the characteristics of low investment and little impact on the surrounding environment. It is a research hotspot in soil remediation in recent years and also the technical application direction vigorously advocated in China, so as to avoid the transformation of soil remediation into an earthwork project or a cement kiln supporting project. In the in-situ treatment mode, low-energy-consumption and weak-disturbance technologies such as in-situ multiphase injection still have great development space at the application level.

[0003] The in-situ injection remediation technology uses certain construction equipment to inject chemical or biological remediation agents into contaminated groundwater or soil to reduce the concentration of pollutants and mitigate or eliminate their impact on the environment. The construction purpose of in-situ injection is to fully mix the treatment agent and pollutants in the underground environment. Common in-situ injection forms mainly include injection well injection, direct push injection, high-pressure jet grouting injection, and in-situ deep mixing injection, etc.

[0004] Among them, injection well injection is to build an injection well, input the repair material into the injection well under normal pressure or low pressure, and then enter the target repair area through the diffusion of the repair material. The repair process can be repeatedly injected in multiple rounds and combined with an extraction well to achieve the purpose of agent diffusion. However, during the use of the injection well, due to insufficient injection pressure, the liquid agent often surges upward during injection, resulting in slurry bleeding and backflow phenomena, which is particularly obvious during the injection of injection wells in low-permeability formations. At the same time, when it is necessary to inject gas into the underground environment, which is beneficial to the degradation of organic pollutants by aerobic microorganisms and to open and dredge the soil pore channels distributed in the underground environment, the existing injection wells will show deficiencies at this time, because they can neither ensure the simultaneous injection of gas phase and liquid phase nor intermittently inject liquid during the gas injection process. Summary of the Invention

[0005] To overcome the defects of the prior art, the present invention provides an in-situ multiphase integrated injection well device and an in-situ multiphase injection method for soil remediation, so as to solve the problems that the existing in-situ injection well cannot ensure the simultaneous injection of gas phase and liquid phase, the injection pressure of liquid agent is insufficient in low-permeability formations, and it is easy to infiltrate downward from the dominant channels in high-permeability formations.

[0006] To achieve the above object, an in-situ multiphase integrated injection well device is provided, including:

[0007] Well pipe, an annular cavity is formed inside the pipe wall of the well pipe. An air inlet for connecting an air source is provided at the upper end of the well pipe. A plurality of air injection ports are provided on the outer side of the pipe wall of the well pipe. A plurality of liquid injection holes are provided on the pipe wall of the well pipe and are arranged along the axial direction of the well pipe and penetrate through. The aperture of the liquid injection hole gradually increases from the end facing the outside of the well pipe to the end facing away from the outside of the well pipe. The hole wall of the liquid injection hole is arc-shaped;

[0008] Support core column, coaxially arranged inside the well pipe. A plurality of convex ribs are formed on the side surface of the support core column and are arranged along the axial direction of the support core column. The convex ribs correspond to the positions of the liquid injection holes. The shape and size of the cross-section of the convex ribs are adapted to the shape and size of the longitudinal section of the liquid injection holes. An annular sliding cavity is formed between the support core column and the inner side of the pipe wall of the well pipe. A groundwater detection instrument is installed on the support core column;

[0009] Liquid injection mechanism, including a movable ring plate, a plurality of spokes and a nozzle for spraying liquid phase repair fluid. The movable ring plate is movably sleeved outside the support core column. The movable ring plate is provided with a plurality of radial holes. The middle parts of the spokes are slidably arranged in the radial holes. One end of each spoke is equipped with an electric roller. The side surface of the support core column supports the electric roller. The end surface of the other end of the spoke is attached to the inner side of the pipe wall of the well pipe. The nozzle is installed at the other end of the spoke. After the electric roller rotates, the movable ring plate moves along the axial direction of the support core column. When the electric roller moves to the side of the convex rib away from the support core column, the other end of the spoke extends into the liquid injection hole to align the nozzle with the outside of the pipe wall of the well pipe.

[0010] Further, the plurality of air injection ports are arranged at intervals along the axial direction of the well pipe.

[0011] Further, each air injection port includes a plurality of air injection openings, and the plurality of air injection openings are arranged at intervals along the circumferential direction of the well pipe.

[0012] Further, the plurality of liquid injection holes are arranged at intervals along the axial direction of the well pipe.

[0013] Further, each liquid injection hole includes a plurality of liquid injection openings, and the plurality of liquid injection openings are arranged at intervals along the circumferential direction of the well pipe.

[0014] Further, the convex ribs are arranged in a circle along the circumferential direction of the support core column.

[0015] Further, a duct is formed inside the spoke. One end of the duct penetrates through the end face of the other end of the spoke. The nozzle is installed at the port of one end of the duct. The nozzle is connected with an infusion tube for conveying the repair liquid, and the infusion tube is accommodated in the duct.

[0016] Further, one end of the supporting core column is connected to the inner side of the pipe wall of the well pipe through a plurality of support rods.

[0017] The present invention provides a method for in-situ multiphase injection for soil remediation using an in-situ multiphase integrated injection well device, including the following steps:

[0018] Vertically bury the in-situ multiphase integrated injection well device in the contaminated soil to be remediated;

[0019] Connect the gas transmission pipe to the air inlet of the well pipe, and connect the infusion tube to the nozzle of the liquid injection mechanism;

[0020] Input the gas into the cavity of the well pipe through the air inlet, and release it into the contaminated soil to be remediated through the gas injection port of the well pipe, and / or start the electric roller of the liquid injection mechanism to make the electric roller rotate, so that the liquid injection mechanism moves along the axial direction of the supporting core column. When the electric roller walks to the side of the rib on the supporting core column away from the supporting core column, the other end of the spoke extends into the liquid injection hole to align the nozzle with the outer side of the pipe wall of the well pipe. Convey the repair liquid to the nozzle through the infusion tube, and spray it to the contaminated soil outside the pipe wall of the well pipe through the nozzle under high pressure.

[0021] The beneficial effects of the present invention are as follows: The in-situ multiphase integrated injection well device of the present invention integrates the well pipe and the supporting core column. The whole set of devices is arranged on the same well, avoiding repeated well construction, saving costs while improving efficiency. The present invention overcomes the problem of insufficient injection pressure in the previous injection wells. The infusion tube can be externally connected to high-pressure equipment, and the injection pressure of the liquid medicine can reach dozens of megapascals. Although the in-situ multiphase integrated injection well device of the present invention has been integrated, the gas injection channel and the liquid injection channel are still separated, thus avoiding the problem that the diffusion radius of the repair liquid is reduced due to mutual interference during gas or liquid injection. The in-situ multiphase integrated injection well device of the present invention integrates the groundwater detection instrument into the integrated well, eliminating the need to build another well to monitor groundwater. Each well can cooperate with each other to verify the diffusion effect of the medicine or the change of the conventional indexes of groundwater quality by measuring the concentration of corresponding substances. The in-situ multiphase integrated injection well device of the present invention organically combines the gas injection, liquid injection and groundwater monitoring of the integrated well, supplementing and complementing each other. Description of the Drawings

[0022] Other features, objects, and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments read in conjunction with the accompanying drawings:

[0023] Figure 1 It is a schematic structural diagram of an in-situ multiphase integrated injection well device according to an embodiment of the present invention.

[0024] Figure 2 It is a top view of an in-situ multiphase integrated injection well device according to an embodiment of the present invention.

[0025] Figure 3 It is a schematic structural diagram of a liquid injection mechanism according to an embodiment of the present invention. Specific Embodiments

[0026] The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related invention and are not intended to limit the invention. Additionally, it should be noted that for the sake of description, only parts related to the invention are shown in the drawings.

[0027] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and embodiments.

[0028] Refer to Figures 1 to 3 As shown, the present invention provides an in-situ multiphase integrated injection well device, including: a well pipe 1, a support core column 2, and a liquid injection mechanism 3.

[0029] An annular cavity a is formed inside the pipe wall of the well pipe 1. An air inlet b for connecting a gas source is provided at the upper end of the well pipe 1. A plurality of gas injection ports c are provided on the outer side of the pipe wall of the well pipe 1. A plurality of liquid injection holes d are provided on the pipe wall of the well pipe 1 and are arranged along the axial direction of the well pipe 1 and penetrate through. The aperture of the liquid injection hole d gradually increases from the end of the liquid injection hole d facing the outside of the well pipe 1 to the end of the liquid injection hole d facing away from the outside of the well pipe 1. The hole wall of the liquid injection hole d is arc-shaped.

[0030] In this embodiment, the pipe wall of the well pipe is a hollow pipe wall. Specifically, the well pipe includes an outer pipe 12 and an inner pipe 11. The inner pipe is coaxially arranged inside the outer pipe. The pipe orifices of the inner pipe and the outer pipe are closed by end plates. The outer pipe is provided with an air inlet b, a gas injection port c, and an outer orifice. The inner pipe is provided with an inner orifice. The position of the inner orifice corresponds to that of the outer orifice. Specifically, the inner orifice and the outer orifice are coaxially arranged. The inner orifice and the outer orifice are circular orifices. The aperture of the inner orifice is larger than that of the outer orifice. A sealing flange is connected between the inner orifice and the outer orifice. The sealing flange is arranged in a circle along the circumferential direction of the inner and outer orifices. The sealing flange is trumpet-shaped. A cavity a is formed by enclosing the inner pipe, the outer pipe, the end plate, and the sealing flange.

[0031] When repairing contaminated soil to be repaired, a gas (such as air or oxygen) is injected into the cavity through an air inlet and into the contaminated soil to be repaired through an air injection port.

[0032] As a preferred embodiment, multiple air injection ports c are arranged at intervals along the axial direction of the well pipe 1.

[0033] In this embodiment, each air injection port c includes a plurality of air injection ports c. The plurality of air injection ports c are arranged at intervals along the circumferential direction of the well pipe 1.

[0034] The supporting core column 2 is coaxially arranged inside the well pipe 1. Multiple ribs 21 are formed on the side surface of the supporting core column 2 along the axial direction of the supporting core column 2. The ribs 21 correspond to the positions of the liquid injection holes d. The shape and size of the cross-section of the ribs 21 are adapted to the shape and size of the longitudinal section of the liquid injection holes d. An annular sliding cavity is formed between the supporting core column 2 and the inner side of the pipe wall of the well pipe 1.

[0035] One end of the supporting core column is connected to the inner side of the pipe wall of the well pipe 1 through a plurality of support rods 22.

[0036] In this embodiment, the lower end of the supporting core column is connected to the inner side of the lower end of the pipe wall of the well pipe 1 through a plurality of support rods 22. The plurality of support rods are arranged at equal intervals.

[0037] The liquid injection mechanism 3 includes a movable ring plate 31, a plurality of spokes 32, and a nozzle for spraying the liquid-phase repair liquid 30.

[0038] Specifically, the movable ring plate 31 is movably sleeved outside the supporting core column 2. The movable ring plate 31 is provided with a plurality of radial holes.

[0039] In this embodiment, the outer diameter of the movable ring plate is adapted to the inner diameter of the well pipe. The movable ring plate fits against the inner side of the side wall of the well pipe (i.e., the inner pipe wall on the side facing the supporting core column).

[0040] The middle part of the spoke 32 slides in the radial hole. One end of the spoke 32 is equipped with an electric roller 34. The side surface of the supporting core column 2 supports the electric roller 34. The end surface of the other end of the spoke 32 fits against the inner side of the pipe wall of the well pipe 1.

[0041] The nozzle is installed at the other end of the spoke 32.

[0042] After the electric roller 34 rotates, the movable ring plate 31 moves along the axial direction of the supporting core column 2. When the electric roller 34 moves to the side of the rib 21 away from the supporting core column 2, the other end of the spoke 32 extends into the liquid injection hole d so that the nozzle is aligned with the outer side of the pipe wall of the well pipe 1.

[0043] As a preferred embodiment, multiple liquid injection holes d are arranged at intervals along the axial direction of the well pipe 1. The liquid injection holes and the air injection ports are arranged alternately.

[0044] In the embodiment, each liquid injection hole d includes a plurality of liquid injection holes d. The plurality of liquid injection holes d are arranged at intervals along the circumferential direction of the well pipe 1.

[0045] As a preferred embodiment, the convex ribs 21 are arranged in a circle along the circumferential direction of the supporting core column 2.

[0046] Referring to Figure 2 As shown, a channel e is formed inside the spoke 32. One end of the channel e penetrates through the end face of the other end of the spoke 32. The nozzle is installed at the port of one end of the channel e. The nozzle is connected with an infusion pipe 33 for transporting the repair liquid 30. The infusion pipe 33 is accommodated in the channel e. The orifice of the other end of the channel is opened at the upper part of the spoke.

[0047] In this embodiment, a driving motor is installed on the spoke, and the driving motor is drivingly connected to the electric roller. The electric roller includes a rubber wheel and a wheel shaft coaxially connected to the rubber wheel. The driving motor is drivingly connected to the wheel shaft.

[0048] In this embodiment, the nozzle is a gem nozzle dedicated to a high-pressure water jet. The nozzle is connected with a high-pressure plunger pump through a high-pressure flexible infusion pipe. After the repair liquid (liquid medicine) is pressurized in the high-pressure plunger pump, it reaches the gem nozzle through the high-pressure flexible infusion pipe. When the movable ring plate reaches the liquid injection hole, the gem nozzle switch is opened, and the liquid medicine is injected into the corresponding soil layer.

[0049] The column body of the supporting core column is formed with convex ribs. The lower end of the column body is fixedly connected to the lower end of the support rod well pipe. Monitoring equipment is installed on the supporting core column. The monitoring equipment installed on the supporting core column includes groundwater detection instruments such as a pH meter, a conductivity meter, and an oxidation-reduction potential meter, which perform real-time online monitoring on the groundwater at the injection point. At the same time, the column body with convex ribs and the inner pipe and the closed flange of the well pipe form a wavy annular sliding cavity, achieving the effect that the liquid injection mechanism can move up and down, and when the end of the spoke extends into the liquid injection hole and the electric roller is closed, the movable ring plate can be fixed to realize the high-pressure injection of the liquid.

[0050] The in-situ multiphase integrated injection well device of the present invention has the functions of gas injection, liquid injection, and monitoring, and does not require repeated well construction.

[0051] The in-situ multiphase integrated injection well device of the present invention can realize the simultaneous or segmented injection of gas and liquid, and can also be used alone as a groundwater monitoring well.

[0052] The unique liquid injection mechanism of the in-situ multiphase integrated injection well device of the present invention can realize the annular injection at different heights of the underground soil layer.

[0053] The in-situ multiphase integrated injection well device of the present invention has a liquid injection cavity capable of fixing a high-pressure water jet device, solving the problems of insufficient injection pressure in low-permeability formations and easy pressure relief in high-permeability formations.

[0054] The present invention provides a method for in-situ multiphase injection for soil remediation using an in-situ multiphase integrated injection well device, comprising the following steps:

[0055] S1. Vertically bury the in-situ multiphase integrated injection well device in the contaminated soil to be remediated.

[0056] S2. Connect the gas transmission pipe to the air inlet b of the well pipe, and connect the liquid infusion pipe 33 to the nozzle of the liquid injection mechanism 3.

[0057] S3. Input gas into the cavity a of the well pipe 1 through the air inlet b, and release it into the contaminated soil to be remediated through the gas injection port c of the well pipe 1, and / or turn on the electric roller 34 of the liquid injection mechanism 3 to make the electric roller 34 rotate, so that the liquid injection mechanism 3 moves along the axial direction of the support core column 2. When the electric roller 34 walks to the side of the rib 21 on the support core column 2 away from the support core column 2, the other end of the spoke 32 extends into the liquid injection hole d to align the nozzle with the outside of the wall of the well pipe 1, transport the repair liquid 30 to the nozzle through the liquid infusion pipe 33, and spray it to the contaminated soil outside the wall of the well pipe 1 through the nozzle under high pressure.

[0058] In this embodiment, the gas released into the contaminated soil to be remediated through the gas injection port c and the contaminated soil outside the wall of the well pipe 1 sprayed under high pressure by the nozzle can be carried out successively or synchronously.

[0059] The in-situ multiphase integrated injection well device of the present invention integrates the well pipe and the support core column, and the whole set of devices is arranged on the same well, avoiding repeated well construction, saving costs while improving efficiency.

[0060] Although the in-situ multiphase integrated injection well device of the present invention has been integrated, the gas injection channel and the liquid injection channel are still separated, thus avoiding the problem that the diffusion radius of the repair liquid is reduced due to mutual interference during gas or liquid injection.

[0061] The in-situ multiphase integrated injection well device of the present invention integrates the groundwater detection instrument into the integrated well, eliminating the need to build another well for groundwater monitoring. Each well can cooperate with each other to verify the diffusion effect of the medicament or the change of the conventional indexes of groundwater quality by measuring the concentration of corresponding substances.

[0062] The in-situ multiphase integrated injection well device of the present invention organically combines gas injection, liquid injection and groundwater monitoring of the integrated well, complementing each other.

[0063] The above description is only a preferred embodiment of the present application and an explanation of the technical principles applied. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solution formed by mutually replacing the above features with technical features (but not limited to) having similar functions disclosed in the present application.

Claims

1. An in-situ multiphase integrated injection well device, characterized in that, Comprising: A well pipe, an inner cavity is formed inside the pipe wall of the well pipe, an air inlet for connecting an air source is provided at the upper end of the well pipe, a plurality of air injection ports are provided on the outer side of the pipe wall of the well pipe, a plurality of liquid injection holes are provided on the pipe wall of the well pipe and are arranged along the axial direction of the well pipe and penetrate through, the aperture of the liquid injection hole gradually increases from one end facing the outside of the well pipe to the other end facing away from the outside of the well pipe, and the pore wall of the liquid injection hole is arc-shaped; A support core column, coaxially arranged inside the well pipe, a plurality of convex ribs are formed on the side surface of the support core column and are arranged along the axial direction of the support core column, the convex ribs correspond to the positions of the liquid injection holes, the shape and size of the cross section of the convex ribs are adapted to the shape and size of the longitudinal section of the liquid injection holes, an annular sliding cavity is formed between the support core column and the inner side of the pipe wall of the well pipe, and a groundwater detection instrument is installed on the support core column; A liquid injection mechanism, comprising a movable ring plate, a plurality of spokes and a nozzle for injecting a liquid-phase repair liquid, the movable ring plate is movably sleeved outside the support core column, the movable ring plate is provided with a plurality of radial holes, the middle part of the spoke is slidably arranged in the radial hole, one end of the spoke is provided with an electric roller, the side surface of the support core column supports the electric roller, the end surface of the other end of the spoke is attached to the inner side of the pipe wall of the well pipe, the nozzle is installed at the other end of the spoke, after the electric roller rotates, the movable ring plate moves along the axial direction of the support core column, when the electric roller moves to the side of the convex rib away from the support core column, the other end of the spoke extends into the liquid injection hole to align the nozzle with the outside of the pipe wall of the well pipe.

2. The in-situ multiphase integrated injection well device according to claim 1, characterized in that The plurality of air injection ports are arranged at intervals along the axial direction of the well pipe.

3. The in-situ multiphase integrated injection well device according to claim 2, wherein Each air injection port comprises a plurality of air injection openings, and the plurality of air injection openings are arranged at intervals along the circumferential direction of the well pipe.

4. The in-situ multiphase integrated injection well device according to claim 1, characterized in that, The plurality of liquid injection holes are arranged at intervals along the axial direction of the well pipe.

5. The in-situ multiphase integrated injection well device according to claim 4, characterized in that, Each liquid injection hole comprises a plurality of liquid injection openings, and the plurality of liquid injection openings are arranged at intervals along the circumferential direction of the well pipe.

6. The in-situ multiphase integrated injection well device according to claim 1, characterized in that, The convex ribs are arranged in a circle along the circumferential direction of the support core column.

7. The in-situ multiphase integrated injection well device according to claim 1, wherein, A hole channel is formed inside the spoke, one end of the hole channel penetrates through the end surface of the other end of the spoke, the nozzle is installed at the port of one end of the hole channel, and the nozzle is connected with an infusion pipe for transporting the repair liquid, and the infusion pipe is accommodated in the hole channel.

8. The in-situ multiphase integrated injection well device according to claim 1, characterized in that One end of the support core column is connected to the inner side of the pipe wall of the well pipe through a plurality of support rods.

9. A in-situ multiphase injection method for soil remediation using the in-situ multiphase integrated injection well device according to any one of claims 1 to 8, characterized in that, Including the following steps: Vertically bury the in-situ multiphase integrated injection well device in the contaminated soil to be repaired; Connect the gas transmission pipe to the air inlet of the well pipe, and connect the infusion pipe to the nozzle of the liquid injection mechanism; Input gas into the cavity of the well pipe through the air inlet, and release it into the contaminated soil to be repaired through the gas injection port of the well pipe. Start the electric roller of the liquid injection mechanism to make the electric roller rotate, so that the liquid injection mechanism moves along the axial direction of the support core column. When the electric roller moves to the side of the rib on the support core column away from the support core column, the other end of the spoke extends into the liquid injection hole to align the nozzle with the outside of the wall of the well pipe. Transport the repair liquid to the nozzle through the liquid delivery pipe, and spray it onto the contaminated soil to be repaired on the outside of the wall of the well pipe through the nozzle.

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