Deep pollution in-situ suction, injection and stirring integrated curing equipment and construction method thereof

Abstract

The invention discloses deep pollution in-situ suction-injection-stirring integrated curing equipment and a construction method thereof, and the equipment is characterized in that the equipment comprises a porous pipe drill rod and a suction-injection-stirring integrated drill bit; a water injection hole, a grouting hole, a reverse water suction hole, a reverse mud discharge hole and a high-pressure air hole are formed in the porous pipe drill rod in the axial direction of the porous pipe drill rod. The method has the advantages that the deep polluted soil (such as below 10m) can be directly solidified, different-position excavation is not needed, and the problems of large excavation depth, high cost and high safety risk are solved. Secondary pollution can be avoided, a negative pressure system formed by the inverted mud suction nozzle and the inverted mud hole can suck polluted mud generated by drilling and stirring in real time, the polluted mud is stored in an external device, and the situation that the mud overflows out of the ground to cause secondary pollution is effectively prevented. The equipment is simple in structure and good in economical efficiency, compared with a pure stirring process, disturbance to non-polluted soil and the dosage of curing agents are reduced through high-pressure cutting and precise grouting, meanwhile, the construction efficiency is improved through integrated operation, and the comprehensive cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of environmental geotechnical engineering technology, specifically to a deep-contamination in-situ suction, injection, stirring and solidification integrated equipment and its construction method. Background Technology

[0002] With industrialization and urbanization, soil pollution has become increasingly prominent, especially the treatment of deeply contaminated soil (such as that from chemical and mining areas), which is extremely difficult. Traditional ex-situ treatment requires large-scale excavation, which is deep, costly, and prone to causing pollutant diffusion. Existing in-situ solidification technologies, such as simple injection processes, suffer from uneven mixing and poor solidification effects; while simple mixing processes disturb uncontaminated soil and require large amounts of reagents. In addition, contaminated mud generated during drilling can easily overflow to the surface, causing secondary pollution. Therefore, there is an urgent need for equipment and methods that can integrate drilling, mud removal, grouting, and mixing to achieve precise, efficient, and environmentally friendly solidification of deeply contaminated soil. Summary of the Invention

[0003] 1. Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a deep-contamination in-situ suction, injection, and mixing integrated curing device and its construction method, which has advantages such as precise in-situ curing, avoidance of secondary pollution, improved mixing effect, and good economy, thus solving the problems mentioned above.

[0004] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: a deep contamination in-situ suction and stirring integrated solidification device, comprising a porous tubular drill rod and a suction and stirring integrated drill bit; The multi-hole drill pipe is provided with water injection holes, grouting holes, back suction holes, back discharge mud holes and high-pressure air holes along its axial direction. Each hole is independently configured and used to transport water, solidification agent, water suction, mud discharge and high-pressure air respectively. The integrated suction and stirring drill bit is connected to the end of the multi-hole drill rod and integrates a cutting head, a cutting nozzle, a high-pressure water nozzle, a high-pressure slurry nozzle, a reverse mud suction nozzle, and expandable and retractable stirring blades. The cutting nozzle and high-pressure water nozzle are connected to the water injection hole, the high-pressure slurry nozzle is connected to the grouting hole, the reverse mud suction nozzle is connected to the reverse mud hole, and the expandable and retractable stirring blades are connected to the drill rod through a transmission mechanism to expand or retract within the borehole.

[0005] Preferably, the multi-hole drill rod has a structure with multiple parallel tubes built in, and the water injection hole, grouting hole, back suction hole, back discharge mud hole and high-pressure air hole are respectively set in different parallel tubes.

[0006] Preferably, the cutting nozzle is located at the front end of the cutting head and is used to spray high-pressure water to cool and assist in cutting the soil; the high-pressure water nozzle and the high-pressure slurry nozzle are located on the side wall of the drill bit and are inclined to form a rotating cutting flow; the reverse mud suction nozzle is located on the side wall of the drill bit and is connected to the reverse mud suction hole for sucking up contaminated mud.

[0007] Preferably, the expandable stirring blade is connected to the internal drive device of the drill rod via a hydraulic transmission mechanism. When the stirring blade is deployed, it has an airfoil structure and is used for stirring and mixing inside the borehole.

[0008] The core design of this device is: in-situ precision solidification: through the integrated design of the multi-hole drill rod and drill bit, it can directly solidify deep contaminated soil (such as below 10m) without the need for off-site excavation, thus solving the problems of large excavation depth, high cost and high safety risks.

[0009] To avoid secondary pollution: The negative pressure system formed by the reverse mud suction nozzle and the reverse mud discharge hole can suck up the polluted mud generated by drilling and agitation in real time and store it in an external device, effectively preventing the mud from overflowing onto the ground and causing secondary pollution.

[0010] Improved mixing effect: The expandable and retractable mixing blades combined with high-pressure grouting achieve synergy between mechanical mixing and fluid injection, which enables the solidification agent to be fully mixed with the contaminated soil, avoids stratification, and improves the solidification strength and uniformity.

[0011] Good economic efficiency: Compared with the simple mixing process, this equipment reduces the disturbance to non-contaminated soil and the amount of solidification agent used through high-pressure cutting and precise grouting. At the same time, the integrated operation improves construction efficiency and reduces overall costs.

[0012] A method for in-situ absorption, injection, and mixing-integrated curing of deep-seated contamination, using any of the curing equipment described above, includes the following steps: (a) Install the suction and mixing integrated drill bit and the multi-hole drill rod, rotate the drill rod and spray high-pressure water through the cutting nozzle to cool the cutting head and cut the soil to form a borehole until the top of the deep contaminated soil layer is reached. (b) Open the reverse mud suction nozzle and reverse water suction hole to form negative pressure, continue drilling down to the bottom of the deep contaminated soil layer, and at the same time, pump the contaminated mud to the external storage device through the reverse mud suction nozzle and reverse mud suction hole; (c) Stop drilling and water spraying from the cutting nozzle, lift the drill rod, and at the same time open the high-pressure water nozzle and high-pressure air hole. Rotate the drill rod to perform high-pressure cutting on the deep contaminated soil, and the resulting contaminated mud is continuously pumped out through the back-drainage mud system. (d) When the drill rod is raised to the top of the deep contaminated soil layer, stop the high-pressure water, high-pressure air and backfilling operations; then lower the drill rod to the bottom of the contaminated soil layer, unfold the expandable mixing blades, and inject the solidification agent through the grouting hole; (e) Rotate and lift the drill rod to allow the mixing blades to fully mix the solidification agent with the contaminated soil, while the backfilling system continues to operate to prevent the mud from overflowing onto the ground. (f) When the mixing is raised to a preset height above the top of the contaminated soil layer, stop grouting and mixing, lower the drill rod to the top of the contaminated soil layer, retract the mixing blades, raise and remove the drill rod to complete the current hole position solidification operation.

[0013] In step (b), the negative pressure of the reverse sludge suction nozzle is formed by the reverse suction water through the contraction section inside the reverse suction hole, and after mixing with the sludge in the reverse sludge hole, the sludge is sucked to the external storage device. The negative pressure value and the sludge discharge flow rate can be controlled by adjusting the reverse suction water flow rate and velocity to adapt to different soil conditions.

[0014] In step (d), the curing agent is cement grout or chemical curing agent, and the injection pressure is adjusted by a matching high-pressure grouting pump. The grouting volume is matched with the lifting speed to ensure uniform mixing.

[0015] In step (e), the rotational speed of the drill rod is increased by 0.5-2.0 m / min, and the stirring range after the stirring blades are deployed is greater than 6.0-10.0 times the diameter of the borehole.

[0016] In step (f), the preset height is 2.0 m. After the drill rod sinks to the top of the contaminated soil layer, the mixing blades are fully retracted before the drill rod is lifted.

[0017] Throughout the construction process, a real-time monitoring system was used to control the parameters of water injection, grouting, mud removal, and mixing in order to achieve precise in-situ solidification and avoid secondary pollution.

[0018] The working principle of this equipment is based on the multi-functional integration of multi-hole drill rods and drill bits. Through the sequential control of drilling, mud removal, grouting and mixing, it achieves in-situ solidification of contaminated soil.

[0019] Drilling and mud removal stage: The drill rod rotates and descends, the cutting head cuts the soil, and simultaneously the cutting nozzle sprays high-pressure water for cooling and lubrication. When drilling reaches the top of the contaminated soil layer, the reverse mud suction nozzle and reverse water suction hole are activated to create a negative pressure system and a high-speed mixing flow of reverse water and mud, sucking up the contaminated mud produced in the borehole and discharging it to an external storage device through the reverse mud suction hole. Drilling continues to the bottom of the contaminated soil layer to prevent mud overflow.

[0020] High-pressure cutting and mud removal stage: After stopping drilling, raise the drill pipe and simultaneously open the high-pressure water nozzle and high-pressure air vent. High-pressure fluid is used to rotate and cut the contaminated soil, breaking it into mud. The mud removal system continues to operate, pumping the mud out to achieve borehole cleaning.

[0021] Grouting and mixing stage: The drill rod is lowered to the bottom of the contaminated soil layer, and the expandable mixing blades are deployed through the transmission mechanism. At the same time, the solidification agent is injected into the grouting hole. The drill rod rotates and is lifted, and the mixing blades force the agent to mix with the contaminated soil. Meanwhile, the mud discharge system maintains negative pressure to prevent mud from flowing up from the hole.

[0022] Final stage: When the mixer is raised to a preset height (e.g., 2.0m) above the top of the contaminated soil layer, stop grouting and mixing, lower the drill rod to the top of the contaminated soil layer, and remove the drill rod after the mixing blades 13 retract, thus completing the solidification.

[0023] Throughout the process, real-time monitoring systems (such as pressure sensors and flow meters) are used to control water injection, grouting, sludge discharge, and mixing parameters to ensure precise operation.

[0024] (III) Beneficial Effects Compared with existing technologies, this invention provides a deep-contamination in-situ suction, injection, and mixing integrated solidification device and its construction method, which has the following beneficial effects: This in-situ suction-mixing solidification equipment and its construction method for deep contaminated soil can achieve precise in-situ solidification. Through the integrated design of the multi-hole drill rod and drill bit, it can directly solidify deep contaminated soil (e.g., below m), eliminating the need for off-site excavation and solving the problems of large excavation depth, high cost, and significant safety risks. It also avoids secondary pollution. The negative pressure system formed by the reverse mud suction nozzle and reverse mud discharge hole can extract contaminated mud generated during drilling and mixing in real time and store it in an external device, effectively preventing mud from overflowing onto the ground and causing secondary pollution.

[0025] It offers good economic benefits. Compared to simple mixing processes, this equipment reduces disturbance to uncontaminated soil and the amount of solidifying agent used through high-pressure cutting and precise grouting. Simultaneously, integrated operation improves construction efficiency and reduces overall costs. It improves mixing effects; the expandable and retractable mixing blades combined with high-pressure grouting achieve synergy between mechanical mixing and fluid injection, ensuring thorough mixing of the solidifying agent and contaminated soil, preventing stratification, and improving solidification strength and uniformity. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of an in-situ suction and stirring integrated solidification device for deep contamination proposed in this invention; Figure 2 This is a cross-sectional schematic diagram of the porous tube drill rod in an in-situ suction and stirring integrated solidification device for deep contamination proposed in this invention. Figure 3 This is a flowchart of a construction method for an in-situ suction, injection, and mixing integrated curing device for deep contamination, as proposed in this invention.

[0027] In the diagram: 1-Multi-hole drill rod, 2-Integrated suction, injection and stirring drill bit, 3-Water injection hole, 4-Grouting hole, 5-Back suction water hole, 6-Back discharge mud hole, 7-High pressure air hole, 8-Cutting head, 9-Cutting nozzle, 10-High pressure water nozzle, 11-High pressure slurry nozzle, 12-Back discharge mud suction nozzle, 13-Expandable and retractable stirring blades, 14-Transmission mechanism. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Please see Figure 1-3 A deep-contamination in-situ suction and stirring integrated solidification device includes a porous pipe drill rod 1 and a suction and stirring integrated drill bit 2; The multi-hole drill pipe 1 is provided with water injection hole 3, grouting hole 4, back suction water hole 5, back discharge mud hole 6 and high-pressure air hole 7 along its axial direction. Each hole is independently configured and used to transport water, solidification agent, water suction, mud discharge and high-pressure air respectively. The suction and mixing integrated drill bit 2 is connected to the end of the multi-hole pipe drill rod 1 and integrates a cutting head 8, a cutting nozzle 9, a high-pressure water nozzle 10, a high-pressure slurry nozzle 11, a reverse mud suction nozzle 12, and a retractable mixing blade 13. Among them, the cutting nozzle 9 and the high-pressure water nozzle 10 are connected to the water injection hole 3, the high-pressure slurry nozzle 11 is connected to the grouting hole 4, the reverse mud suction nozzle 12 is connected to the reverse mud discharge hole 6, and the expandable and retractable stirring blade 13 is connected to the drill rod drive through the transmission mechanism 14 to realize the expansion or contraction in the borehole.

[0030] The multi-hole drill pipe 1 has a built-in structure of multiple parallel pipes. Water injection holes 3, grouting holes 4, backflow water holes 5, backflow mud holes 6, and high-pressure air holes 7 are respectively located in different parallel pipes. A cutting nozzle 9 is located at the front end of the cutting head 8 and is used to spray high-pressure water to cool and assist in cutting the soil. High-pressure water nozzles 10 and high-pressure slurry nozzles 11 are located on the sidewalls of the drill bit and are inclined to form a rotating cutting flow. A backflow mud suction nozzle 12 is located on the sidewalls of the drill bit and connected to the backflow mud hole 6 for sucking up contaminated mud. Deployable mixing blades 13 are connected to the internal drive device of the drill pipe via a hydraulic transmission mechanism 14. When deployed, the mixing blades have an airfoil structure for mixing within the borehole.

[0031] A method for in-situ absorption, injection, and mixing-integrated curing of deep-seated contamination, using any of the above-mentioned curing equipment, includes the following steps: (a) Install the suction and stirring integrated drill bit 2 and the multi-hole pipe drill rod 1, rotate the drill rod and spray high-pressure water through the cutting nozzle 9 to cool the cutting head 8 and cut the soil to form a borehole until the top of the deep contaminated soil layer is reached. (b) Open the reverse mud suction nozzle 12 and the reverse water suction hole 5 to form a negative pressure, continue drilling down to the bottom of the deep contaminated soil layer, and at the same time, pump the contaminated mud to the external storage device through the reverse mud suction nozzle 12 and the reverse mud suction hole 6. (c) Stop drilling and water spraying from the cutting nozzle 9, lift the drill rod, and at the same time open the high-pressure water nozzle 10 and the high-pressure air hole 7. Rotate the drill rod to perform high-pressure cutting on the deep contaminated soil, and the resulting contaminated mud is continuously pumped out through the back-drainage mud system. (d) When the drill rod is raised to the top of the deep contaminated soil layer, stop the high-pressure water, high-pressure air and backfilling operations; then lower the drill rod to the bottom of the contaminated soil layer, unfold the expandable mixing blades 13, and inject the solidification agent through the grouting hole 4; (e) Rotate and lift the drill rod to allow the mixing blades to fully mix the solidification agent with the contaminated soil, while the backfilling system continues to operate to prevent the mud from overflowing onto the ground. (f) When the mixing is raised to a preset height above the top of the contaminated soil layer, stop grouting and mixing, lower the drill rod to the top of the contaminated soil layer, retract the mixing blades, raise and remove the drill rod to complete the current hole position solidification operation.

[0032] In step (b), the negative pressure of the back-suction nozzle 12 is formed by the back-suction water through the contraction section inside the back-suction hole, and after mixing with the mud in the back-suction hole, the mud is pumped to the external storage device. The negative pressure value and mud discharge flow rate can be controlled by adjusting the back-suction water flow rate and velocity to adapt to different soil conditions.

[0033] In step (d), the curing agent is cement grout or chemical curing agent, and the injection pressure is adjusted by a matching high-pressure grouting pump. The grouting volume is matched with the lifting speed to ensure uniform mixing.

[0034] In step (e), the rotational speed of the drill rod is increased by 0.5-2.0 m / min, and the stirring range after the stirring blades are deployed is greater than 6.0-10.0 times the diameter of the borehole.

[0035] In step (f), the preset height is 2.0 m. After the drill rod sinks to the top of the contaminated soil layer, the mixing blades are fully retracted before the drill rod is lifted.

[0036] Throughout the construction process, a real-time monitoring system was used to control the parameters of water injection, grouting, mud removal, and mixing in order to achieve precise in-situ solidification and avoid secondary pollution.

[0037] The working principle of this equipment is based on the multi-functional integration of the multi-hole drill rod 1 and the drill bit 2. Through the timing control of drilling, mud removal, grouting and mixing, in-situ solidification of contaminated soil is achieved.

[0038] Drilling and mud removal stage: The drill rod rotates and descends, the cutting head 8 cuts the soil, and simultaneously the cutting nozzle 9 sprays high-pressure water for cooling and lubrication. When drilling reaches the top of the contaminated soil layer, the reverse mud suction nozzle 12 and the reverse water suction hole 5 are activated to form a negative pressure system and a high-speed mixing flow of reverse water and mud, sucking up the contaminated mud generated in the borehole and discharging it to an external storage device through the reverse mud suction hole 6. Drilling continues to the bottom of the contaminated soil layer to prevent mud overflow.

[0039] High-pressure cutting and mud removal stage: After stopping drilling, raise the drill pipe and simultaneously open the high-pressure water nozzle 10 and high-pressure air hole 7. Use high-pressure fluid to rotate and cut the contaminated soil, breaking it into mud. The mud removal system continues to work, pumping the mud out to achieve borehole cleaning.

[0040] Grouting and mixing stage: The drill rod is lowered to the bottom of the contaminated soil layer, and the expandable mixing blades 13 are deployed through the transmission mechanism 14. At the same time, the solidification agent is injected into the grouting hole 4. The drill rod rotates and is lifted, and the mixing blades 13 forcibly mix the agent with the contaminated soil. Meanwhile, the backflow system maintains negative pressure to prevent mud from flowing up in the hole.

[0041] Final stage: When the mixer is raised to a preset height (e.g., 2.0m) above the top of the contaminated soil layer, stop grouting and mixing, lower the drill rod to the top of the contaminated soil layer, and remove the drill rod after the mixing blades 13 retract, thus completing the solidification.

[0042] Throughout the process, real-time monitoring systems (such as pressure sensors and flow meters) are used to control water injection, grouting, sludge discharge, and mixing parameters to ensure precise operation.

[0043] Example 1: In-situ solidification of deep cohesive contaminated soil. Conditions of contaminated soil: a chemical plant site. The contaminated soil is cohesive, 10-15m deep, with high water content and low permeability.

[0044] Equipment parameters: The multi-hole drill rod 1 has a built-in structure of multiple parallel tubes, with an outer diameter of 200mm and a length of 20m. Water injection hole 3 delivers high-pressure water at a pressure of 25MPa; grouting hole 4 delivers cement slurry at a pressure of 40MPa; backflow hole 5 delivers backflow water to create a negative pressure of -0.08MPa; high-pressure air hole 7 has a pressure of 0.7MPa.

[0045] The cutting head 8 of the suction and stirring integrated drill bit 2 is made of cemented carbide, and the cutting nozzle 9 has a diameter of 2mm. The high-pressure water nozzle 10 and the high-pressure slurry nozzle 11 are arranged at an angle of 30°. The reverse mud suction nozzle 12 is located at the bottom of the drill bit. The expandable and retractable stirring blade 13 has a diameter of 2000mm after unfolding (drill hole diameter of 250mm) and is controlled by the hydraulic transmission mechanism 14.

[0046] Construction process: Install drill bit 2 and multi-hole drill rod 1, rotate the drill rod (speed 1m / min) and drill down, use cutting nozzle 9 to spray high-pressure water to assist drilling. When drilling reaches 10m (top of the contaminated soil layer), start the backfilling system.

[0047] Continue drilling down to 15m (bottom of the contaminated soil layer), while simultaneously using the reverse-draining mud suction nozzle 12 to pump the contaminated mud into the storage tank.

[0048] Stop drilling and water spraying from cutting nozzle 9, raise the drill rod (speed 0.5m / min), and simultaneously open high-pressure water nozzle 10 and high-pressure air hole 7 to perform high-pressure cutting on the contaminated soil. The mud discharge system continuously pumps out mud.

[0049] After raising the drill rod to 10m, stop the high-pressure fluid and mud discharge. Lower the drill rod to 15m, deploy the mixing blades 13, and inject cement slurry into the grouting hole 4 at a flow rate of 90L / min. Rotate the drill rod (speed 20rpm) and raise it (speed 1m / min). The mixing blades 13 mix the cement slurry with the contaminated soil, while the mud discharge system maintains negative pressure to prevent overflow.

[0050] Raise the drill pipe to 8m (2m above the contaminated top) and stop the operation. Lower the drill pipe to 10m, retract the mixing blades by 13 and then remove it.

[0051] Results: The solidified contaminated soil strength reached 0.5 MPa, was uniformly mixed, and no mud overflowed.

[0052] Example 2: In-situ solidification of sandy contaminated soil. Conditions of contaminated soil: Sandy contaminated soil in a mining area, depth 5-10m, high permeability, and easy to flow.

[0053] Equipment parameters: Multi-hole drill rod 1, outer diameter 200mm, high-pressure water pressure 30MPa (for sand cutting); grouting hole 4, injection of chemical curing agent (sodium silicate based), pressure 45MPa; reverse discharge mud negative pressure -0.09MPa; mixing blade 13, unfolded diameter 2000mm (drilling diameter 250mm).

[0054] Construction process: Drill the drill rod to 5m (top of contaminated area) and start the reverse mud discharge system. Drill to 10m (bottom of contaminated area). Raise the drill rod (speed 2m / min), use the high-pressure water nozzle 10 at 25MPa to cut the sand and soil, and start the mud discharge system. Lower the drill rod to 10m, deploy blade 13, grout at 45MPa (flow rate 120L / min), and raise the drill rod at 1.5m / min for mixing.

[0055] Raise to 3m (2m above the contamination top) and stop; lower to 5m and remove after shrinking the blades.

[0056] Result: The permeability coefficient of the contaminated soil decreased to 10 after solidification. -6 cm / s, reducing the amount of pesticide used by 20%, which is economical.

[0057] In summary, this in-situ suction-mixing solidification equipment and its construction method for deep contaminated soil can achieve precise in-situ solidification. Through the integrated design of the multi-hole drill rod 1 and drill bit 2, it can directly solidify deep contaminated soil (e.g., below 10m) without the need for off-site excavation, solving the problems of large excavation depth, high cost, and high safety risks. Secondary pollution can be avoided. The negative pressure system formed by the reverse mud suction nozzle 12 and the reverse mud discharge hole 6 can extract the contaminated mud generated during drilling and mixing in real time and store it in an external device, effectively preventing mud from overflowing onto the ground and causing secondary pollution.

[0058] It offers good economic benefits. Compared to simple mixing processes, this equipment reduces disturbance to uncontaminated soil and the amount of solidifying agent used through high-pressure cutting and precise grouting. Simultaneously, integrated operation improves construction efficiency and reduces overall costs. It improves mixing effects; the expandable / retractable mixing blades 13 combined with high-pressure grouting achieve synergy between mechanical mixing and fluid injection, ensuring thorough mixing of the solidifying agent and contaminated soil, preventing stratification, and improving solidification strength and uniformity.

[0059] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0060] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A deep-seated contamination in-situ suction, injection, and mixing integrated solidification device, characterized in that, It includes a multi-hole drill pipe (1) and a suction and stirring integrated drill bit (2); The multi-hole drill pipe (1) is provided with water injection hole (3), grouting hole (4), back suction hole (5), back discharge mud hole (6) and high-pressure air hole (7) along its axial direction. Each hole is independently configured and used to transport water, solidification agent, water suction, mud discharge and high-pressure air respectively. The suction and stirring integrated drill bit (2) is connected to the end of the multi-hole drill rod (1) and integrates a cutting head (8), a cutting nozzle (9), a high-pressure water nozzle (10), a high-pressure slurry nozzle (11), a reverse mud suction nozzle (12), and expandable and retractable stirring blades (13). The cutting nozzle (9) and the high-pressure water nozzle (10) are connected to the water injection hole (3), the high-pressure slurry nozzle (11) is connected to the grouting hole (4), the reverse mud suction nozzle (12) is connected to the reverse mud hole (6), and the expandable and retractable stirring blade (13) is connected to the drill rod drive through the transmission mechanism (14) to realize expansion or contraction in the borehole.

2. The deep-seated contamination in-situ suction, injection, and stirring integrated solidification equipment according to claim 1, characterized in that: The multi-hole drill rod (1) has multiple parallel pipe structures built in, with water injection hole (3), grouting hole (4), back suction water hole (5), back discharge mud hole (6) and high-pressure air hole (7) respectively set in different parallel pipes.

3. The in-situ suction, injection, and stirring integrated solidification device for deep contamination according to claim 1, characterized in that: The cutting nozzle (9) is located at the front end of the cutting head (8) and is used to spray high-pressure water to cool and assist in cutting the soil. The high-pressure water nozzle (10) and the high-pressure slurry nozzle (11) are located on the side wall of the drill bit and are inclined to form a rotating cutting flow. The reverse mud suction nozzle (12) is located on the side wall of the drill bit and is connected to the reverse mud suction hole (6) for sucking up contaminated mud.

4. The in-situ suction, injection, and stirring integrated solidification equipment for deep contamination according to claim 1, characterized in that: The expandable stirring blade (13) is connected to the internal drive device of the drill rod through a hydraulic transmission mechanism (14). When the stirring blade is unfolded, it has an airfoil structure and is used to stir and mix inside the borehole.

5. A method for in-situ suction, injection, and mixing integrated solidification construction of deep-seated contamination, employing the solidification equipment described in any one of claims 1-4, characterized in that, Includes the following steps: (a) Install the suction and stirring integrated drill bit (2) and the multi-hole pipe drill rod (1), rotate the drill rod and spray high-pressure water through the cutting nozzle (9) to cool the cutting head (8) and cut the soil to form a borehole until the top of the deep contaminated soil layer is reached; (b) Open the reverse discharge mud suction nozzle (12) and reverse suction water hole (5) to form negative pressure, continue drilling down to the bottom of the deep contaminated soil layer, and at the same time, pump the contaminated mud to the external storage device through the reverse discharge mud suction nozzle (12) and reverse discharge mud hole (6); (c) Stop drilling and spray water from the cutting nozzle (9), lift the drill rod, and at the same time open the high-pressure water nozzle (10) and the high-pressure air hole (7), rotate the drill rod to perform high-pressure cutting on the deep contaminated soil, and the contaminated mud formed continues to be pumped out through the back-drainage mud system; (d) When the drill rod is raised to the top of the deep contaminated soil layer, stop the high-pressure water, high-pressure air and backfilling operations; then lower the drill rod to the bottom of the contaminated soil layer, unfold the expandable mixing blades (13), and inject the solidification agent through the grouting hole (4); (e) Rotate and lift the drill rod to allow the mixing blades to fully mix the solidification agent with the contaminated soil, while the backfilling system continues to operate to prevent the mud from overflowing onto the ground. (f) When the mixing is raised to a preset height above the top of the contaminated soil layer, stop grouting and mixing, lower the drill rod to the top of the contaminated soil layer, retract the mixing blades, raise and remove the drill rod to complete the current hole position solidification operation.

6. The construction method according to claim 5, characterized in that, In step (b), the negative pressure of the back-suction sludge suction nozzle (12) is formed by the back-suction water through the contraction section inside the back-suction hole, and after mixing with the sludge in the back-suction sludge hole, the sludge is sucked to the external storage device. The negative pressure value and sludge discharge flow rate can be controlled by adjusting the back-suction water flow rate and velocity to adapt to different soil conditions.

7. The construction method according to claim 5, characterized in that, In step (d), the curing agent is cement grout or chemical curing agent, and the injection pressure is adjusted by a matching high-pressure grouting pump. The grouting volume is matched with the lifting speed to ensure uniform mixing.

8. The construction method according to claim 5, characterized in that, In step (e), the rotational speed of the drill rod is increased by 0.5-2.0 m / min, and the stirring range after the stirring blades are deployed is greater than 6.0-10.0 times the diameter of the borehole.

9. The construction method according to claim 5, characterized in that, In step (f), the preset height is 2.0 m. After the drill rod sinks to the top of the contaminated soil layer, the mixing blades are fully retracted before the drill rod is lifted.

10. The construction method according to any one of claims 5-9, characterized in that, Throughout the construction process, a real-time monitoring system was used to control the parameters of water injection, grouting, mud removal, and mixing in order to achieve precise in-situ solidification and avoid secondary pollution.

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