In-situ medicine injection repairing structure for fixed-depth injection

Abstract

The utility model relates to an in-situ medicine injection repairing structure for fixed-depth injection. The in-situ medicine injection repairing structure comprises an inner tube, an outer tube and a filling layer. The upper part of the inner pipe is a solid pipe section which is connected with a pressure gauge, a flow meter and a valve, and the lower part of the inner pipe is a screen pipe of which the upper and lower ends are provided with expandable grouting plugs; the outer pipe sleeves the inner pipe, and sieve holes corresponding to the repair depth are formed in the side wall of the outer pipe; the filling layer is located between the inner pipe and the outer pipe and made of cement bentonite materials, and a plurality of radial gaps are formed through cutting of pressurized liquid. Depth-keeping sealing is achieved through nesting of the inner pipe and the outer pipe and the grouting plug, it is guaranteed that the agent is accurately injected into a target layer, and waste and pollution are avoided; the diffusion uniformity of the medicament is enhanced by radial gaps of the filling layer; the pressure and flow double-control system is adaptive to different pollution and stratum conditions. The method is suitable for polluted sites with large permeability difference, and has the advantages of good remediation effect, high efficiency and small pollution.

Description

Technical Field

[0001] This invention provides a repair structure, and particularly relates to an in-situ drug injection repair structure for fixed-depth injection. Background Technology

[0002] Currently, common methods for removing organically contaminated soil include physical, chemical, and biological methods, with chemical oxidation / reduction remediation technology being the most widely used chemical method. However, ex-situ remediation involves the development and transportation of contaminated soil, which raises concerns about spillage and the volatilization of pollutants, particularly volatile pollutants, which have a more severe impact.

[0003] In-situ chemical oxidation / reduction technology involves injecting oxidants / reducing agents into the contaminated area through direct injection or injection wells, transforming pollutants into non-toxic or less toxic substances. It offers advantages such as good treatment results, high construction efficiency, and minimal secondary pollution. Therefore, to avoid secondary pollution, the application of in-situ remediation technology is becoming increasingly widespread.

[0004] Existing technologies mainly include in-situ direct injection and in-situ injection well injection.

[0005] The commonly used injection method for in-situ direct injection is high-pressure rotary jet injection. This method is a one-time injection and cannot continuously inject chemicals into the contaminated area. Even if re-spraying is performed, there is still uneven diffusion of the agent. Moreover, the ground after rotary spraying is in a muddy state, which is difficult to restore its load-bearing capacity for a long time, and it has certain limitations.

[0006] In-situ injection wells deliver remediation agents to the contaminated area through a series of injection wells. While this technology allows for continuous injection of agents into the contaminated soil, variations in remediation depth and geological strata can lead to difficulties in agent injection. Furthermore, in sites with significant differences in permeability, the agent tends to diffuse preferentially into more permeable strata, resulting in substantial waste of the agent and limited coverage, uneven mixing, and poor targeting. Utility Model Content

[0007] In order to overcome the shortcomings of the prior art, this application provides an in-situ drug injection repair structure with fixed-depth injection, which solves the problems of uneven diffusion of repair agents and difficulty in continuous drug injection in the prior art. It can achieve precise, uniform and continuous drug injection, and effectively improve the repair effect.

[0008] To solve the above-mentioned technical problems, this utility model provides the following technical solution: an in-situ drug injection repair structure for fixed-depth injection, including an inner tube, an outer tube sleeved outside the inner tube, and a filling layer filling the space between the inner tube and the outer tube;

[0009] The upper part of the inner tube is a solid pipe section, and the lower part is a screen pipe. The solid pipe section is connected to a pressure gauge, a flow meter, and a valve. The upper and lower ends of the screen pipe are respectively equipped with expandable grouting plugs.

[0010] The outer tube has sieve holes on its side wall, and the location of the sieve holes corresponds to the remediation depth of the contaminated soil; the grouting plug and the expanded plug seal against the inner wall of the outer tube to form a closed injection section.

[0011] The filling layer is a solidifiable material layer, and multiple radial slits are formed inside it by pressurized liquid cutting. The slits are connected to the sieve holes of the sieve tube and the outer tube.

[0012] Preferably, the filling layer is made of cement-bentonite material, and the radial slots are formed by pressurized liquid cutting before solidification.

[0013] Preferably, the outer diameter of the outer tube is larger than the outer diameter of the inner tube, and the two are coaxially arranged.

[0014] Preferably, the pressure gauge and flow meter are used to monitor the injection pressure and flow rate, respectively, and the valve is used to control the input of the drug liquid.

[0015] Preferably, the grout plug is made of rubber and achieves sealing by expanding the pressurized liquid or gas.

[0016] Preferably, the sieve holes of the outer tube are distributed at intervals along the axial direction, and the distribution range matches the target repair depth.

[0017] Preferably, the radial slits extend in a direction perpendicular to the axial direction of the inner tube, for uniform diffusion of the agent.

[0018] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0019] 1) This device can inject at a fixed depth and can be used for the remediation of contamination at different depths;

[0020] 2) The flow rate of this device is controllable, and the dosage of the reagent can be controlled according to different pollution concentrations to achieve the best ratio and good remediation effect;

[0021] 3) The pressure of this device is controllable, and barriers are set in both the upper and lower layers at the specified injection depth, resulting in more uniform drug diffusion and a larger range of influence.

[0022] Other advantages, objectives and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be taught from the practice of this invention. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the installation of an in-situ drug injection repair structure for fixed-depth injection according to this utility model;

[0024] Figure 2 This is a schematic diagram illustrating a specific implementation of the in-situ drug injection repair structure for fixed-depth injection according to this utility model.

[0025] As shown in the figure:

[0026] 1. Inner pipe; 2. Outer pipe; 3. Filling layer; 4. Screen pipe; 5. Grouting plug; 6. Grouting plug; 7. Pressure gauge; 8. Flow meter; 9. Valve. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] It should be noted that the terms "vertical," "horizontal," "up," "down," "left," "right," and similar expressions used in this article are for illustrative purposes only and do not represent the only possible implementation.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein in the description of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0030] like Figure 1 As shown, an in-situ drug injection repair structure for fixed-depth injection includes an inner tube 1, an outer tube 2, and a filling layer 3. The upper part of the inner tube 1 is a solid section connected to a pressure gauge 7, a flow meter 8, and a valve 9 for monitoring and controlling injection parameters; the lower part is a sieve tube 4, with expandable grout plugs 5 and 6 at its upper and lower ends for sealing the target repair layer. The outer tube 2 is fitted over the inner tube 1, and its sidewalls have sieve holes corresponding to the repair depth. After expansion, the grout plugs 5 and 6 seal against the inner wall of the outer tube 2, forming a closed injection section. The filling layer 3, located between the inner tube 1 and the outer tube 2, is made of cement-bentonite material and is formed by pressurized liquid cutting into multiple radial slits. These slits communicate with the sieve holes of the sieve tube 4 and the outer tube 2 for uniform drug diffusion.

[0031] In this embodiment, the inner tube 1 and the outer tube 2 are connected by a coaxial sleeve. The solid section of the inner tube 1 is fixed to the upper end of the outer tube 2 by a flange or thread. The screen tube 4 corresponds to the screen hole area of ​​the outer tube 2. The grouting plugs 5 and 6 are located at the upper and lower ends of the screen tube 4, respectively. They are expanded by high-pressure liquid or gas injection, forming an annular seal with the inner wall of the outer tube 2, limiting the injection section to the target remediation depth. The filling layer 3 is filled by pumping cement bentonite grout to fill the annular gap between the inner tube 1 and the outer tube 2. Before the grout initially sets, a pressurized liquid pressure of 0.5 MPa is introduced to cut the filling layer 3 outward along the screen holes of the screen tube 4 and the outer tube 2, forming 6 to 8 radial slits with a width of 2 to 3 mm. The slits extend perpendicularly to the axis of the inner tube 1 and penetrate into the contaminated soil. The coaxial sleeve design of the inner and outer tubes, combined with the strict correspondence between the screen holes of the outer tube and the remediation depth, ensures that the agent is released only through the target contaminated layer, avoiding shallow or deep leakage. The expansion sealing mechanism of the grouting plug can adapt to different formation deformations, with a sealing pressure ≥0.3MPa, effectively isolating non-target areas.

[0032] The radial slits created by pressurized liquid cutting directly connect the screen tube and the sieve holes of the outer tube, allowing the agent to diffuse evenly into the contaminated soil along the slits. This solves the problem of uneven diffusion caused by the reliance on soil permeability in traditional technologies. The cement-bentonite mix balances the strength and cutability of the filling layer, with an initial setting time of 4 hours, providing an operational window for slit formation. Pressure gauges and flow meters provide real-time data feedback, and valves are used to adjust the injection flow rate and pressure to adapt to different contamination concentrations and soil permeability.

[0033] like Figure 2 As shown, this in-situ chemical injection remediation structure achieves precise depth sealing through a nested design of inner and outer tubes and expandable grouting plugs 5 and 6, ensuring that the chemical is injected only into the target remediation layer, avoiding chemical waste and secondary pollution. The filling layer 3 uses cement-bentonite material, which forms radial slits through pressurized liquid cutting, significantly improving the uniformity and range of chemical diffusion. The control system, consisting of pressure gauge 7, flow meter 8, and valve 9, can monitor and adjust the injection pressure and flow rate in real time to adapt to different contamination concentrations and formation conditions. The sieve holes of the outer tube 2 are spaced axially, matching the target remediation depth, further enhancing the targeting and efficiency of the remediation. This structure is particularly suitable for contaminated sites with large differences in permeability, offering advantages such as good remediation effect, high construction efficiency, and low secondary pollution.

[0034] at the same time,

[0035] 1. Fixed-depth injection and sealing design:

[0036] The nested structure of inner and outer tubes and expandable grouting plugs 5 and 6 achieve a fixed-depth seal, ensuring that the agent is accurately injected into the target repair layer and preventing the agent from spreading to non-target areas.

[0037] Traditional direct injection cannot continuously control the depth, while injection well technology is limited by formation permeability; this design solves the problem of formation differences by using the two screen holes of the outer tube and the grouting plug for linkage sealing.

[0038] 2. Radial slot filling technique:

[0039] The filler layer 3 is formed by pressurized liquid cutting to create radial slits, which enhances the uniformity of drug diffusion and expands the range of influence.

[0040] Traditional filling layers are solid structures, and the diffusion of reagents depends on the permeability of the formation, resulting in uneven mixing; this design guides the distribution of reagents by artificially cutting fissures.

[0041] 3. Dual pressure and flow control system:

[0042] The injection parameters can be adjusted in real time through pressure gauge 7, flow meter 8 and valve 9 to adapt to different pollution concentrations and formation conditions.

[0043] Existing technologies mostly use fixed parameters for drug injection, which lacks flexibility; this design improves repair efficiency through dynamic adjustment.

[0044] Implementation points and quantitative parameters

[0045] 1. Key equipment models and parameters:

[0046] Pressure gauge: Select Y100 type anti-vibration pressure gauge with an accuracy of ±0.5% and a range of 0-50kPa, which is suitable for a typical injection pressure of 20kPa.

[0047] Flow meter: LZB15 glass rotor flow meter, measuring range 0.5~5m 3 / h, meeting the requirements for precise control of drug flow rate.

[0048] Grouting plug: EPDM rubber expansion plug (pressure resistant 0.3MPa) is used. After expansion, the diameter reaches 1.2 times the inner diameter of the outer pipe 2 to ensure sealing.

[0049] 2. Filler layer materials and processes:

[0050] Cement-bentonite mix ratio: cement:bentonite:water = 1:2:0.8 (mass ratio), initial setting time 4 hours, final setting time 24 hours.

[0051] Pressurized liquid parameters: Use clean water as the cutting medium, pressurize to 0.5MPa, and continuously inject for 10 minutes to form 6 to 8 radial slits (2 to 3 mm wide).

[0052] 3. Structural dimensions and suitable scenarios:

[0053] Inner tube 1 and outer tube 2: Inner tube outer diameter 25mm (material 304 stainless steel), outer tube outer diameter 63mm (PVCU material), suitable for remediating contaminated soil at a depth of 2-6m.

[0054] Screen hole distribution: The outer tube has two screen holes spaced 200mm apart, with a hole diameter of 5mm and an open area ratio of 15%, suitable for medium to low permeability formations (permeability coefficient ≤10). -4 (cm / s).

[0055] In one feasible embodiment:

[0056] Case Background: A site contaminated with chlorinated hydrocarbons, requiring remediation at a depth of 2-3 meters, with a soil density of 1.8 t / m³. 3 The design influence radius of a single well is 1.5m.

[0057] Implementation process:

[0058] 1. Well construction:

[0059] Drill to a depth of 3.5m, install the outer pipe 2 and position the screen holes to a depth of 2-3m.

[0060] Insert inner tube 1 and pressurize (0.3MPa) to expand grouting plugs (5, 6) to seal the target layer.

[0061] Inject cement-bentonite slurry, let it stand for 3 days, and then apply pressure to cut and form radial slits.

[0062] 2. Injection parameters:

[0063] Dosage: Add 1% of the soil mass; 127 kg of reagent is needed per well (soil volume = π × 1.5). 2 ×1=7.07m 3 Mass = 7.07 × 1.8 = 12.7t).

[0064] Injection pressure: 20 kPa (adapted to formation permeability), flow rate control: 2 m³ / s. 3 / h, injection time 63.5 minutes.

[0065] Repair results:

[0066] Chemical distribution: It diffuses evenly through the cracks, with an influence radius of 1.8m (exceeding the design value). After remediation, the concentration of chlorinated hydrocarbons in the soil decreased from 500mg / kg to 50mg / kg (removal rate of 90%).

[0067] Economic efficiency: Compared with traditional injection wells, the chemical utilization rate is increased by 30% and the construction period is shortened by 20%.

[0068] During use, the first step is construction preparation, including site leveling and equipment inspection. Then, drilling to the predetermined depth, installing the outer pipe, and accurately positioning the screen holes to the target repair depth are performed. Next, the inner pipe is inserted, and the grouting plug is expanded using high-pressure liquid or gas to seal the target repair layer. Afterward, cement-bentonite grout is injected to fill the annular gap between the inner and outer pipes. Before the grout initially sets, pressurized liquid is introduced to cut the filling layer outward along the screen holes of the outer pipe, forming 6-8 radial cracks with a width of 2-3 mm. After the agent is prepared into a solution, it is injected through the inner pipe. Pressure gauges, flow meters, and valves are used to monitor and adjust the injection pressure and flow rate in real time. The dosage of the agent is determined based on soil quality and pollution concentration, and the injection pressure and flow rate are set according to the formation permeability. The injection time is calculated to ensure that the agent diffuses evenly into the contaminated soil along the radial cracks to achieve the remediation purpose. Finally, the equipment is dismantled, the site is cleaned, and the remediation effect is monitored.

[0069] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. An in-situ injection repair structure for depth injection, comprising an inner tube (1), an outer tube (2) sleeved outside the inner tube (1), and a filling layer (3) filled between the inner tube (1) and the outer tube (2), characterized in that: an upper part of the inner tube (1) is a solid tube section, and a lower part is a screen pipe (4), the solid tube section is connected with a pressure gauge (7), a flow meter (8) and a valve (9); the screen pipe (4) is provided with inflatable grouting plugs (5) and (6) at upper and lower ends thereof respectively; the outer tube (2) is provided with screen holes in a side wall thereof, the screen holes are arranged at positions corresponding to a repair depth of contaminated soil; the grouting plugs (5) and (6) are in sealing abutment with an inner wall of the outer tube (2) after inflation, forming a closed injection section; the filling layer (3) is a layer of coagulable material, and a plurality of radial slits are formed in the filling layer (3) by cutting with pressurized liquid, the slits being in communication with the screen pipe (4) and the screen holes of the outer tube (2).

2. The in-situ injection remediation structure of depth- controlled injection according to claim 1, wherein: The filling layer (3) is made of cement-bentonite material, and the radial slits are formed by cutting with pressurized liquid before coagulation.

3. The in-situ injection remediation structure of depth- controlled injection according to claim 1, wherein: The outer tube (2) has an outer diameter greater than that of the inner tube (1), and the two are coaxially arranged.

4. The in-situ injection remediation structure of depth- controlled injection of claim 1, wherein: The pressure gauge (7) and the flow meter (8) are respectively used for monitoring injection pressure and flow, and the valve (9) is used for controlling input of medicament liquid.

5. The in-situ injection remediation structure of depth- controlled injection of claim 1, wherein: The grouting plugs (5) and (6) are made of rubber material, and are inflated by pressurized liquid or gas to realize sealing.

6. The in-situ injection remediation structure of depth- controlled injection of claim 1, wherein: The screen holes of the outer tube (2) are distributed along an axial direction at intervals, and a distribution range thereof matches a target repair depth.

7. The in-situ injection remediation structure of depth- controlled injection of claim 1, wherein: The radial slits extend in a direction perpendicular to an axial direction of the inner tube (1), and are used for uniform diffusion of medicament.

Images