A high-pressure layered precision injection device for soil and groundwater remediation

Abstract

The utility model discloses a high pressure layered precision injection device for soil and groundwater remediation belongs to environmental remediation technical field. The device includes ground medicine supply system, drilling injection system and pressure relief recovery system. Drilling injection system includes through the multiple medicine injection well pipe (5, 10) of pushing and pulling injection head (4) series connection, the drill bit (7) of setting in the drill string bottom end and install on the multiple high pressure injection head (6) of target depth medicine injection well pipe. The pressure relief recovery system includes a tee pressure relief valve (3), its import connects high pressure plunger pump (1), and its first export is connected pushing and pulling injection head (4) through high pressure injection pipe (8), and its second export connects pressure relief return pipe (9). The utility model discloses through preloading multiple injection head realizes disposable advancement, layered precision injection, and through the pressure relief system recovery residual medicament, has solved the problem of traditional method low efficiency, high risk, easy secondary pollution fundamentally.

Description

Technical Field

[0001] This utility model relates to the field of environmental remediation engineering technology, and in particular to a high-pressure layered precision injection device for the remediation of organic polluted soil and groundwater. Background Technology

[0002] Soil and groundwater remediation is a key technology for restoring the environmental function of contaminated sites. When using in-situ chemical oxidation or bioremediation techniques, liquid remediation agents often need to be injected into the contaminated area underground. Currently, traditional injection methods suffer from the problem of single injection layers. For complex sites with multiple contamination faults, workers need to advance the drill string to a certain depth for injection, then lift the entire drill string out of the ground, disassemble the pipeline to adjust its length, and then drill again to the next depth. This process needs to be repeated, resulting in long construction cycles and high labor intensity. More seriously, when disassembling pressurized pipelines, corrosive or toxic residual agents can easily splash, posing a safety threat to operators and causing secondary contamination of the site. Therefore, there is an urgent need in this field for a new injection device that can achieve one-time drilling, precise layered injection, and safe recovery of residual agents. Utility Model Content

[0003] The purpose of this invention is to overcome the above-mentioned defects of the prior art and provide a high-efficiency, safe and accurate high-pressure layered precision injection device for soil and groundwater remediation.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A high-pressure, layered, precision injection device for soil and groundwater remediation includes:

[0006] Ground-based drug delivery systems are used for mixing, storing, and pumping drugs, including stirred dosing tanks and high-pressure plunger pumps;

[0007] A drilling injection system for drilling holes and injecting chemicals at a specified depth includes a drill bit, multiple detachably connected injection well casings, multiple high-pressure injection nozzles, a high-pressure injection line, and a push-pull injection head. The drill bit, injection well casings, and high-pressure injection nozzles are pre-assembled into a drill string on the ground, wherein at least two high-pressure injection nozzles are installed on injection well casings corresponding to different contamination depths. The push-pull injection head is connected to the top of the drill string and is connected to a surface chemical supply system via the high-pressure injection line.

[0008] The pressure relief and recovery system is used to release and recover residual agents in the pipeline after the injection is completed. It includes a three-way pressure relief valve and a pressure relief return pipe. The inlet of the three-way pressure relief valve is connected to the outlet of the high-pressure plunger pump, its first outlet is connected to the push-pull injection head through the high-pressure injection pipe, and its second outlet is connected to the pressure relief return pipe.

[0009] Preferably, the injection well pipe includes standard pipe sections of different lengths such as 500mm and 1000mm, which can be flexibly combined according to the actual pollution depth to accurately position the high-pressure injection nozzle.

[0010] Preferably, the end of the pressure relief return pipe returns to the stirring dosing tank or a dedicated recovery container to achieve the recycling or safe collection of the agent, eliminating waste and pollution.

[0011] Preferably, the push-pull injection head is a quick connector, which facilitates quick connection and disconnection with the ground high-pressure injection pipe.

[0012] The beneficial effects of this utility model are as follows:

[0013] 1. By pre-installing multiple high-pressure injection nozzles at once, multiple contaminated layers can be injected simultaneously and precisely in a single drilling operation, reducing the injection time per hole by more than 50% and greatly improving construction efficiency.

[0014] 2. The system consisting of a three-way pressure relief valve and a pressure relief return pipe can safely export and recover the residual agent in the high-pressure pipeline after the injection is completed, fundamentally eliminating the risk of agent splashing during the disassembly process, effectively preventing secondary pollution and ensuring the safety of operators.

[0015] 3. It reduces the waste of chemicals caused by splashing and dripping. At the same time, due to the simplification of operation, the number of operators required per shift can be reduced from 4 to 3, thus reducing labor costs and labor intensity.

[0016] 4. It adopts a modular standard injection well pipe and a positionable nozzle design, which can be flexibly configured according to the pollution conditions of different sites, making it widely applicable, easy to operate, and highly reliable. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall system structure of this utility model. In the figure: 1. High-pressure plunger pump; 2. Stirring and dosing tank; 3. Three-way pressure relief valve; 4. Push-pull injection head; 5. 500mm injection well pipe; 6. High-pressure injection nozzle; 7. Drill bit; 8. High-pressure injection pipe; 9. Pressure relief return pipe; 10. 1000mm injection well pipe.

[0018] Figure 2 This is a flowchart of the construction process before the improvement in the background technology.

[0019] Figure 3 This is a flowchart of the improved construction process of this utility model. Detailed Implementation

[0020] The technical solution of this utility model will now be described in detail with reference to all the accompanying drawings, so that those skilled in the art can accurately understand and implement this utility model. The implementation of this utility model mainly covers two core aspects, one of which is based on... Figure 1 The system structure and component connection relationship, secondly based on Figure 2 and Figure 3 A comparison of the work processes and methods.

[0021] Please see Figure 1 This utility model's device systematically integrates three major functional modules. The ground-based drug supply system is located on the ground surface and is mainly responsible for the preparation and delivery of the drug. It includes a stirring dosing tank 2 and a high-pressure plunger pump 1. The inlet of the high-pressure plunger pump 1 is connected to the bottom of the stirring dosing tank 2 via a pipe. The three-way pressure relief valve 3, as a key component for system pressure control, has its inlet directly connected to the outlet of the high-pressure plunger pump 1. The first outlet is connected to the push-pull dosing head 4 via a high-pressure injection pipe 8, and the second outlet is connected to the pressure relief return pipe 9. The end of this return pipe usually returns to the stirring dosing tank 2 or a dedicated recovery container.

[0022] The drilling and injection system extends from the surface to the underground contaminated area, undertaking the functions of drilling and precise chemical delivery. The push-pull injection head 4 serves as the interface between the surface pipeline and the downhole drill string. Multiple injection tubing sections 5 and 10 are sequentially connected below it via threads. These tubing sections can be modularly combined with different lengths to suit the depth of the contaminated layer. High-pressure injection nozzles 6 are pre-installed on the injection tubing corresponding to the target contamination depth; the arrangement of multiple nozzles enables the device to perform layered injection. A drill bit 7 is installed at the bottom of the drill string, responsible for drilling and hole formation. The pressure relief and recovery system is highly integrated with the surface chemical supply system, switching between injection and pressure relief functions via a three-way pressure relief valve 3, ensuring operational safety.

[0023] This utility model innovates the work process through comparison. Figure 2 and Figure 3 This is clearly demonstrated. The traditional, unmodified process flow is as follows: Figure 2 As shown, the previous method employs a layer-by-layer operation mode, requiring repeated cycles of injection tube installation, injection, pressure holding, and pressure release at each injection depth. This process necessitates multiple connections and disconnections of high-pressure pipelines, resulting in low efficiency and a risk of drug splashing. The improved process adopted in this invention is as follows: Figure 3 As shown, the original multi-cycle process is simplified into a single linear process. First, the injection and well casing assembly is completed in one go on the surface. Then, the drilling rig advances the entire drill string to the target depth in one go. Next, injection, pressure holding, and pressure release are performed, and finally, the drill pipe is removed. This process innovation fundamentally eliminates the frequent disassembly of pipelines, achieving a significant improvement in construction efficiency and safety.

[0024] The standard implementation steps of this utility model are as follows, and these steps are consistent with... Figure 3 The improved process shown is completely consistent. First, construction preparation and drill string assembly are carried out. This involves designing a drill string assembly scheme based on pollution survey data. On the surface, the drill bit 7, the injection well casing 5 and 10 (with high-pressure injection nozzles 6 installed at the predetermined depth), and the top push-pull injection head 4 are connected sequentially. This step completes the configuration of all injection units in one go. Next, drilling is performed to the target depth in one go. The drilling rig pushes the entire assembled drill string underground in one go until the bottom nozzle reaches the deepest designed contaminated layer. Then, the high-pressure injection pipe 8 and the push-pull injection head 4 are connected on the surface. Following this, high-pressure injection is performed. The three-way pressure relief valve 3 is switched to the injection path, the high-pressure plunger pump 1 is started, and the pressure is adjusted to the scheme requirements, such as two to ten MPa, to begin synchronous injection into each contaminated layer. After injection, pressure holding and safety pressure relief are performed. Once the injection volume reaches the target, the pump is stopped and pressure is maintained for a period of time to allow the agent to fully diffuse. Then, the three-way pressure relief valve 3 is switched to the pressure relief path, allowing any residual agent in the pipeline to be safely recovered to the designated container via the pressure relief return pipe 9, until the system pressure drops to zero. Finally, the drill string is lifted and moved, removed from the ground and disassembled, and moved to the next injection point.

[0025] In an embodiment of an in-situ chemical oxidation project at an organically contaminated site in Nanjing, this invention demonstrated its high efficiency and precision in multi-layered contamination remediation. The contaminated soil at the site was located at a depth of 1.5 to 2.5 meters, and the contaminated groundwater at a depth of 4.5 to 6.0 meters. During implementation, based on the contaminated strata, seven high-pressure injection nozzles were precisely pre-installed at depths of 1.5 meters, 2.0 meters, 2.5 meters, 4.5 meters, 5.0 meters, 5.5 meters, and 6.0 meters when drilling columns were assembled on the ground. Subsequently, the injection and depressurization were performed in a single, standardized manner. The results showed that the construction period was shortened by approximately 50%, no chemical spraying was required throughout the process, and subsequent monitoring data indicated that the radius of influence of the chemical in the soil exceeded 3.5 meters, achieving the desired remediation effect.

[0026] Another example is a risk management project for halogenated hydrocarbon pollution at a pesticide factory in Shanghai. This invention has demonstrated its reliability and safety in handling pesticides that are prone to clogging and splashing. The contamination depth at the site ranged from one to seven meters, and the pesticide contained carbon powder, iron powder, and had an odor. During implementation, thirteen high-pressure injection nozzles 6 were combined to directly inject the pesticide into the target layer at a pressure of five MPa, and residual pesticide was effectively recovered through a three-way pressure relief valve 3. The implementation effect was particularly significant. The injection work at sixteen contaminated points, originally planned to be completed in eight days, was completed in only four days after using this device. This successfully solved the problem of previous construction teams having to leave the site due to the difficulty in cleaning pesticide splashes, and the injection process did not cause significant pollution to the surface lawn.

[0027] In summary, this utility model achieves... Figure 1 The specific structural innovation shown achieves Figure 3The process innovations described herein have been demonstrated in numerous practical applications, showcasing significant technological advancements and broad applicability. Any equivalent modifications or improvements based on the concept of this utility model should be included within the protection scope of this utility model.

Claims

1. A high-pressure, layered, precision injection device for soil and groundwater remediation, characterized in that, include: The ground-based drug delivery system includes a stirring dosing tank (2) and a high-pressure plunger pump (1). The drilling injection system includes a drill string consisting of a drill bit (7), multiple injection well pipes (5, 10) and a push-pull injection head (4) connected in sequence. At least two of the injection well pipes (5, 10) are equipped with high-pressure injection nozzles (6) located at different depths. The push-pull injection head (4) is connected to the surface drug supply system through a high-pressure injection pipe (8). The pressure relief and recovery system includes a three-way pressure relief valve (3) and a pressure relief return pipe (9); the inlet of the three-way pressure relief valve (3) is connected to the outlet of the high-pressure plunger pump (1), its first outlet is connected to the high-pressure injection pipe (8), and its second outlet is connected to the pressure relief return pipe (9).

2. The high-pressure layered precision injection device according to claim 1, characterized in that, The injection well casing comprises standard sections of different lengths, which are used to assemble a drill string adapted to the target contamination depth.

3. The high-pressure layered precision injection device according to claim 2, characterized in that, The standard pipe section includes a 500mm injection well pipe (5) and a 1000mm injection well pipe (10).

4. The high-pressure layered precision injection device according to claim 1, characterized in that, The end of the pressure relief return pipe (9) is returned to the stirring dosing tank (2) or a dedicated recovery container.

5. The high-pressure layered precision injection device according to claim 1, characterized in that, The push-pull injection head (4) is a quick connector.

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