Double-layer rotary halogen extraction well structure

Abstract

The utility model provides a kind of double-layer rotary halogen extraction well structure.The halogen extraction well structure includes well platform, well pipe rotary drive mechanism, bottom sand pipe, outer rotary well pipe, inner rotary well pipe and be provided between inner and outer rotary well pipe water-permeable filter layer, the inner, outer rotary well pipe all include rotary pipe and fixed pipe with water-permeable hole being opened correspondingly, the well pipe rotary drive mechanism controls the rotary pipe rotation of inner and outer rotary well pipe, to make two well pipes open or close.The utility model's outer rotary well pipe and inner rotary well pipe can dynamically prevent salt and self-cleaning, sustained relative shearing motion is generated between middle rotary pipe wall and crystalline particle in brine or already attached salt, can effectively strip and crush the salt crystal that is deposited on pipe wall;Outer rotary well pipe can be closed respectively, constitute closed circulation flushing circuit jointly, greatly reduce the salt layer dissolution cavity caused by flushing fresh water overflow, solve the problem of well collapse.

Description

Technical Field

[0001] This utility model relates to the field of underground brine extraction technology, specifically a double-layer rotating brine extraction well structure. Background Technology

[0002] The Qarhan Salt Lake, as the largest known potassium-magnesium salt mining area in my country, is a large-scale comprehensive salt deposit mainly composed of brine potassium-magnesium salt deposits. Its brine is rich in beneficial elements such as K⁺ and Mg²⁺. The main cations are K⁺, Na⁺, Mg²⁺, and Ca²⁺, and the main anion is Cl⁻, followed by SO₄²⁻.

[0003] The primary target of mining in the salt lake area is the intercrystalline brine hidden within the salt layers. This brine exists in the pores and fissures of the salt rock and is extracted through brine wells. Based on hydrogeological characteristics, the underground brine of the Qarhan Salt Lake is generally weakly alkaline, with a total dissolved solids (TDS) greater than 300 g / L, and the dominant anions and cations are Cl⁻, Na⁺, and Mg²⁺. During long-term mining operations, with increasing production capacity requirements, surface channel mining can no longer meet the production needs of the salt lake mining area. It is necessary to promote well mining to more efficiently and sustainably extract brine resources buried deeper and with more complex structures.

[0004] The brine of the Qarhan Salt Lake is a complex salt solution. During transportation and extraction, due to evaporation, cooling, or pressure changes, salts such as halite (NaCl) and carnallite (KCl·MgCl2·6H2O) in the brine easily reach supersaturation and crystallize. This can clog the brine pumps, pipelines, and seepage channels around the well walls, directly affecting brine extraction efficiency and even leading to production shutdowns. Flushing with fresh water can dissolve these crystals promptly, ensuring system smooth operation, and is the most common, simple, and efficient method to alleviate salt formation in brine wells. However, the saline soil in the Qarhan Salt Lake area exhibits significant dissolution properties, a characteristic that has long plagued engineering construction in the region. The underlying mechanism of dissolution lies in the large amount of soluble salts in the lake strata, which act as cementing materials in the sedimentary layers, maintaining the stability of the soil structure. When freshwater is injected into brine wells to flush them, the salt minerals in the strata dissolve rapidly, weakening the rock-soil structure and increasing porosity. Under stress, this leads to compressive deformation, forming erosion channels in the surface and deeper layers, causing well-circumferential collapse and ground subsidence. Currently, in some mining areas of the Qarhan Salt Lake with unstable geological conditions, brine wells with a radius of about ten meters require weekly backfilling and compaction to reinforce them due to salt deposition caused by freshwater flushing. Therefore, a systematic method to reduce well-circumferential collapse caused by salt deposition from freshwater flushing is urgently needed. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a double-layer rotating well casing circulation flushing well structure system. This system can form a closed loop internal circulation consisting of "outer rotating well casing - permeable filter media - inner rotating well casing", which reduces the salt layer dissolution cavities caused by the overflow of flushing fresh water at the source. At the same time, it introduces a strong vortex effect and stirring action, which promotes the flushing and unblocking of salt deposits.

[0006] To achieve the above objectives, this utility model provides a double-layer rotating brine well structure. The brine well structure includes a well platform, a double-layer rotating well casing, a well casing rotation drive mechanism, and a bottom sand settling pipe. The well platform is located on the ground. The double-layer rotating well casing includes an outer rotating well casing, an inner rotating well casing, and a permeable filter layer disposed between the inner and outer rotating well casings. The outer rotating well casing includes an outer rotating pipe, an outer pipe protection pipe, and an outer pipe isolation net. The outer pipe protection pipe includes two fixed pipes disposed on the inner and outer sides of the outer rotating pipe. The outer pipe isolation net includes two layers of filter nets disposed on the outer wall of the outer outer pipe protection pipe and the inner wall of the inner outer pipe protection pipe. Corresponding water permeable holes are provided on the outer rotating pipe and the outer pipe protection pipe. The inner rotating well casing includes an inner rotating pipe, an inner pipe protection pipe, and an inner pipe isolation net. The inner pipe protection pipe includes a water permeable hole disposed on the inner... The well casing has two fixed pipes, one inside and one outside. The inner pipe isolation net is installed on the outer wall of the outer inner pipe protection pipe. Corresponding water permeable holes are provided on the inner rotating pipe and the inner protective pipe. The lower ends of both the outer and inner rotating pipes are rotatably connected to the bottom sand-collecting pipe, and the pipe openings extend out of the well platform. The pipe opening of the inner rotating pipe is higher than that of the outer rotating pipe. The well casing rotation drive mechanism includes an outer pipe drive motor and an inner pipe drive motor. The outer pipe drive motor is driven by the outer rotating pipe through a rotation mechanism and controls the rotation of the outer rotating pipe, so that the water permeable holes of the outer rotating pipe and the outer protective pipe open correspondingly or close staggeredly. The inner pipe drive motor is driven by the inner rotating pipe through a rotation mechanism and controls the rotation of the inner rotating pipe, so that the water permeable holes of the inner rotating pipe and the inner protective pipe open correspondingly or close staggeredly.

[0007] The preferred technical solution of this utility model is as follows: the well pipe rotation drive mechanism further includes a support frame, and both the outer pipe drive motor and the inner pipe drive motor are fixed on the support frame; an external gear is provided at the wellhead of the outer rotating pipe, and an internal gear is provided at the wellhead of the inner rotating pipe; a first transmission gear is fixedly connected to the output shaft of the outer pipe drive motor, and the first transmission gear meshes with the external gear; a second transmission gear is fixedly connected to the output shaft of the inner pipe drive motor, and the second transmission gear meshes with the internal gear.

[0008] The preferred technical solution of this utility model is as follows: the bottom sand settling pipe is a sand settling pipe cast with anti-corrosion cement, including two layers of steel pipes with smooth coatings on the inner and outer surfaces and slag cement filling the space between the two layers of steel pipes; the bottoms of the two outer protective pipes and the two inner protective pipes are all fixed to the top surface of the bottom sand settling pipe; the bottom of the outer rotating pipe is rotatably connected to the bottom sand settling pipe through an outer rotating well pipe bearing; the bottom of the inner rotating pipe is rotatably connected to the bottom sand settling pipe through an inner rotating well pipe bearing; the outer rotating well pipe bearing and the inner rotating well pipe bearing are both fixed to the top surface of the bottom sand settling pipe.

[0009] The beneficial effects of this utility model are: (1) The outer rotating well pipe and the inner rotating well pipe of this utility model together form a closed-loop flushing circuit; the flushing fluid is strictly limited to the closed loop formed by “outer rotating well pipe-permeable filter material-inner rotating well pipe”, which cuts off the path of fresh water intrusion into the formation, realizes the flushing of salt in the brine well and unblocks it, greatly reduces the salt layer dissolution cavities caused by the overflow of flushing fresh water, can solve the problem of well perimeter collapse from the source, protect the original formation structure, and maintain the stability of the well wall.

[0010] (2) Both the outer and inner rotating well pipes of this utility model adopt a three-layer coaxial structure of “protective pipe-rotating pipe-protective pipe”. The protective pipe is fixed, and the rotating pipe is driven by the ground starter and rotated by bearing support. It dynamically prevents salt deposition and self-cleaning. The middle rotating pipe wall and the crystal particles or salt deposits in the brine generate a continuous relative shearing motion, which can effectively peel off and crush the salt crystals that are about to be deposited on the pipe wall. Both the inner and outer rotating well pipes are equipped with isolation nets to prevent soil from entering the water permeable holes of the pipe wall and causing blockage.

[0011] (3) Closed-loop flushing circuit optimizes the flow field and improves flushing efficiency; the closed-loop flushing circuit introduces a strong eddy effect and stirring action, which enhances the turbulent diffusion and convective shear stress between the flushing fluid and the surface of the salt deposits. At the same time, the insoluble particles or crystalline particles flushed down are carried out of the well with the circulating fluid flow, avoiding secondary settling and blockage at the bottom of the well or at the filter. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a cross-sectional view of the wellhead area in this utility model; Figure 3 yes Figure 1 Sectional view of AA'; Figure 4 yes Figure 1 Sectional view of BB'; Figure 5 This is a schematic diagram of the internal and external rotating well pipe structure in this utility model; Figure 6 This is a top view of the present invention; Figure 7 This is a schematic diagram of the internal and external rotating well casing structure in this utility model; Figure 8 This is a schematic diagram of the inner rotating well casing protection pipe and the outer rotating well casing protection pipe in this utility model; Figure 9 This is a schematic diagram of the nozzle layout in this utility model.

[0013] In the diagram: 1. Outer rotating well casing; 100. Outer rotating pipe; 101. Outer casing protection pipe; 102. Outer casing isolation net; 103. Outer casing water perforation hole; 104. Outer rotating well casing bearing; 2. Well platform; 3. Inner rotating well casing; 300. Inner rotating pipe; 301. Inner casing protection pipe; 302. Inner casing isolation net; 303. Inner casing water perforation hole; 304. Inner rotating well casing bearing; 4. Bottom sand settling pipe; 5. Permeable filter layer; 6. External gear; 7. Internal gear; 8. Surface water tank; 9. Underground water tank; 10. Pressurized flushing pipeline; 11. Infusion pipeline; 12. Pressurized pump; 13. First return pipeline; 14. Second return pipeline; 15. Return pump; 16. Filter screen; 17. Control valve; 18. Nozzle; 19. Support frame; 20. Outer tube drive motor; 21. Inner tube drive motor; 22. First transmission gear; 23. Second transmission gear; 24. PLC control box. Detailed Implementation

[0014] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the present invention. In order to better illustrate the specific embodiments of the present invention, some parts in the drawings may be omitted, enlarged or reduced, and do not represent the actual product size. It is understandable for those skilled in the art that some well-known structures and their descriptions in the drawings may be omitted. Based on the specific embodiments of the present invention, all other specific embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] In the description of this utility model, it should be noted that the terms "front", "rear", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0016] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0017] The embodiment provides a double-layer rotating brine well structure, such as Figures 1 to 9 As shown, the brine extraction well structure includes a well platform 2, a double-layer rotating well casing, a well casing rotation drive mechanism, a bottom sand settling pipe 4, and a closed-loop flushing pipeline. The well platform 2 is located on the ground. The double-layer rotating well casing includes an outer rotating well casing 1, an inner rotating well casing 3, and a permeable filter media layer 5 disposed between the inner and outer rotating well casings. The outer rotating well casing 1 includes an outer rotating pipe 100, an outer pipe protection pipe 101, and an outer pipe isolation net 102. The outer pipe protection pipe 101 includes two fixed pipes disposed on the inner and outer sides of the outer rotating pipe 100. The outer pipe isolation net 102 includes two layers of filter screens disposed on the outer wall of the outer outer pipe protection pipe 101 and the inner wall of the inner outer pipe protection pipe 101. The outer pipe 100 and the outer pipe protection pipe 101 are provided with corresponding outer pipe water permeable holes 103; the inner rotating well pipe 3 includes an inner rotating pipe 300, an inner pipe protection pipe 301 and an inner pipe isolation net 302. The inner pipe protection pipe 301 includes two fixed pipes arranged inside and outside the inner rotating pipe 300. The inner pipe isolation net 302 is arranged on the outer wall of the outer inner pipe protection pipe 301. Corresponding inner pipe water permeable holes 303 are provided on the inner rotating pipe 300 and the inner pipe protection pipe 301; the lower ends of the outer rotating pipe 100 and the inner rotating pipe 300 are rotatably connected to the bottom sand settling pipe 4, and the pipe openings extend out of the well platform 2. The pipe opening of the inner rotating pipe 300 is higher than the pipe opening of the outer rotating pipe 100. The isolation net can block small particles that can pass through the gaps between the outer rotating well casing 1 and the inner rotating well casing 3, reducing wear on components such as the rotating well casing and deep well pump in the brine production system. At the same time, the well casing isolation net, together with the outer rotating well casing 1 and the inner rotating well casing 3, forms a "coarse filtration + fine filtration" combined system, which ensures sufficient flow area (responsible for the inner and outer rotating well casings) and provides fine sand-blocking capability (responsible for the isolation net).

[0018] In this embodiment, both the outer rotating well pipe bearing 104 and the inner rotating well pipe bearing 304 are fixed to the top surface of the bottom sand-collecting pipe 4. The outer rotating pipe 100, the outer pipe protection pipe 101, the inner rotating pipe 300, and the inner pipe protection pipe 301 are all made of steel pipe with a wall thickness of 6mm to 8mm. The pipe wall is uniformly provided with water-permeable holes, and the porosity is 12% to 16%. If the porosity is too low (for example, below 10%), the flow area will be too small, and the brine will generate a large head loss when flowing through the screen pipe, reducing the brine extraction efficiency. If the porosity is too high, the screen pipe will not have sufficient strength to resist compression and torsion, resulting in stress deformation, thereby causing sand prevention failure or complete blockage. Both the outer pipe isolation net 102 and the inner pipe isolation net 302 use metal filter screens to prevent soil and debris from entering the permeable holes of the outer rotating well pipe 1 and the inner rotating well pipe 3, causing blockage. The outer diameter of the outer rotating well pipe 1 is 700mm~900mm, and the outer diameter of the inner rotating well pipe 3 is 500mm~600mm. The permeable filter media layer 5 is made of 5mm~10mm gravel. Excessively fine permeable filter media has a high sand-blocking rate but is easily blocked, resulting in poor permeability and severely limiting production capacity. Furthermore, its low strength makes it prone to breakage. Excessively coarse permeable filter media has excellent permeability but cannot effectively block sand; fine formation sand will directly pass through the filter media layer, causing screen blockage and formation sand discharge. It also weakens the support for the well wall. The bottom sedimentation pipe 4 is a sedimentation pipe made of corrosion-resistant cement, including two layers of steel pipes with smooth coatings on the inner and outer surfaces and slag cement filling the space between the two layers of steel pipes; in this way, solid particles in the brine are collected and deposited, preventing damage to the wellbore and brine pump, and ensuring the long-term, stable and efficient operation of brine extraction.

[0019] An embodiment provides a double-layer rotating brine well structure, such as Figure 1 and Figure 6 As shown, the well casing rotation drive mechanism includes an outer casing drive motor 20 and an inner casing drive motor 21. The outer casing drive motor 20 is connected to the outer rotating casing 100 via a rotation mechanism and controls the rotation of the outer rotating casing 100, causing the outer rotating casing 100 and the outer casing water permeable holes 103 of the outer casing protective pipe 101 to open correspondingly or close offset from each other. The inner casing drive motor 21 is connected to the inner rotating casing 300 via a rotation mechanism and controls the rotation of the inner rotating casing 300, causing the inner rotating casing 300 and the inner casing water permeable holes 303 on the inner casing protective pipe 301 to open correspondingly or close offset from each other. The well pipe rotation drive mechanism can be opened in a corresponding manner or closed in a staggered manner; the well pipe rotation drive mechanism also includes a support frame 19, and the outer pipe drive motor 20 and the inner pipe drive motor 21 are both fixed on the support frame 19; an outer gear 6 is provided at the wellhead of the outer rotating pipe 100, and an inner gear 7 is provided at the wellhead of the inner rotating pipe 300; the output shaft of the outer pipe drive motor 20 is fixedly connected to a first transmission gear 22, which meshes with the outer gear 6; the output shaft of the inner pipe drive motor 21 is fixedly connected to a second transmission gear 23, which meshes with the inner gear 7.

[0020] The embodiment provides a double-layer rotating brine well structure, which is also equipped with a closed-loop flushing pipeline, such as... Figures 1 to 9 As shown, the closed-loop flushing pipeline includes an above-ground water storage tank 8, an underground water storage tank 9, and multiple pressurized flushing pipes 10 buried in the permeable filter layer 5. The multiple pressurized flushing pipes 10 are arranged in a ring within the permeable filter layer 5. Each pressurized flushing pipe 10 is laid along the height direction of the brine well body, and both its upper and lower ends extend out of the permeable filter layer 5. Multiple sets of nozzles 18 are installed on each pressurized flushing pipe 10. The above-ground water storage tank 8 is connected to the upper end of the multiple pressurized flushing pipes 10 through a liquid delivery pipe 11, and a pressurized pump 12 is installed on the liquid delivery pipe 11. The lower end of the pressurized flushing pipe 10 extends from the outer wall of the bottom sand settling pipe 4 and is connected to the underground water storage tank 9 through a first return pipe 13. A control valve 17 is installed on the first return pipe 13. The underground water storage tank 9 and the above-ground water storage tank 8 are connected through a second return pipe 14, and a return pump 15 is installed on the second return pipe 14. The first return pipe 13 is an annular or arc-shaped pipe, installed on the outer wall of the bottom sand settling pipe 4. Each pressurized flushing pipe 10 is connected to the first return pipe 13 with a stainless steel filter screen 16. The stainless steel filter screen 16 has two layers: a first layer of 40-60 mesh stainless steel filter screen and a second layer of 100-120 mesh stainless steel filter screen. The well casing stainless steel filter screen uses a woven mat process, resulting in high structural strength, uniform mesh size, and resistance to deformation.

[0021] In the embodiments, such as Figure 4 As shown, the infusion pipeline 11 includes a ring-shaped or arc-shaped water pipe and a connecting pipe. The ring-shaped or arc-shaped water pipe is laid between the outer rotating pipe 100 and the inner rotating pipe 300, and is positioned higher than the well platform 2. The above-ground water storage tank 8 is connected to the ring-shaped or arc-shaped water pipe through the connecting water pipe. The connecting water pipe extends from the opening of the outer rotating pipe 100 into the space between the outer rotating well pipe 1 and the inner rotating well pipe 3. The pressurized flushing pipeline 10 is made of UPVC pipe, which has good corrosion resistance and a smooth inner wall that is not prone to scaling. Figure 9 As shown, a set of nozzles 18 are arranged at intervals of 40 cm to 60 cm on the pressurized flushing pipe 10. Each set of nozzles includes four nozzles, which are horizontally distributed at an angle of 90°. The nozzles 18 are narrow-legged solid conical nozzles, and the material is brass with good comprehensive performance of wear resistance and corrosion resistance.

[0022] In the embodiments, such as Figure 1 and Figure 6As shown, the brine extraction well system also includes a PLC control box 24. The PLC control box 24 is connected to the control terminals of the outer pipe drive motor 20, the inner pipe drive motor 21, the pressurizing pump 12, the control valve 17, and the return pump 15. The PLC control box 24 controls the well pipe rotation drive mechanism to drive the outer rotating well pipe 1 and the inner rotating well pipe 3 to rotate until the water permeable holes on the walls of the two well pipes are staggered and closed. Then, the PLC control box 24 controls the pressurizing pump 12 to introduce fresh water from the surface water storage tank 8 into the pressurized flushing pipe 10 to flush the permeable filter layer 5 with fresh water. At the same time, the PLC control box 24 controls the control valve 17 and the return pump 15 to open, and pump the flushed water back to the surface water storage tank 8 for recycling. When the outer rotating well pipe 1 and the inner rotating well pipe 3 are closed, the PLC control box 18 adjusts the above-ground water storage tank 8 to add fresh water. The pressurization pump 12 then injects the fresh water through the delivery pipe 11 into the pressurized flushing pipe 10, from which it is sprayed out from the nozzles 18, pressurizing and flushing the filter media. The flushed fresh water is collected by the underground water storage tank 9 and then pumped back to the above-ground water storage tank 8 by the return pump 15 and return pipe. When the inner rotating well pipe 3 and the outer rotating well pipe 1 are rotated open to allow brine production, the PLC control box 18 controls the control valve 17 to close. In this embodiment, the PLC control box 18 controls the closing of the rotating well pipes and regulates the pressure and volume of the fresh water flushing to ensure efficient desalination and production operation of the entire brine well system. In this embodiment, the fresh water flushing pressure is controlled between 1.0 MPa and 3.0 MPa to overcome the resistance of formation and well pipe salt deposition and to deliver water into the filter media area without damaging the well pipes and filter pipes. The total flow rate of freshwater rinsing should be controlled at 4 to 6 times the volume of the permeable filter media layer 5, and the rinsing time should be controlled at 80 to 120 minutes. This ensures that the freshwater has sufficient residence time in the filter media area to fully dissolve the salt crystals.

[0023] The double-layer rotary well casing circulating flushing brine well device system of this utility model has the following rotary circulating flushing process: First, the PLC control box 24 adjusts the above-ground water storage tank 8 to introduce fresh water. Next, the PLC control box 24 adjusts the well casing rotation drive mechanism to drive the outer rotary well casing gear 6 and the inner rotary well casing gear 7 respectively, thereby controlling the water permeable holes on the fixed pipe of the outer rotary pipe 100 and the outer pipe protection pipe 101 to be staggered and closed, and the water permeable holes on the fixed pipe of the inner rotary pipe 300 and the inner pipe protection pipe 303 to be staggered and closed. Simultaneously, the control valve 17 is opened to form a closed circulating flushing loop with the pressurized flushing pipeline 10, the pressurized pump 12, the return pump 15, the above-ground water storage tank 8, the underground water storage tank 9, the infusion pipeline 11, the first return pipe 13, and the second return pipe 14. Subsequently, the PLC control box 24 adjusts the pressurized pump 12 to apply pressure, pumping fresh water into the pressurized flushing pipeline 10 to flush and unblock the salt deposits in the permeable filter layer 5. Simultaneously, the PLC control box 24 regulates the return pump 15 to extract and reuse fresh water. In this embodiment, a salinity meter and a water level gauge are installed inside the above-ground water storage tank 8, and the PLC control box 24 monitors the salinity and water level of the circulating flushing fresh water. When the salinity of the circulating fresh water reaches 150 g / L~180 g / L, the PLC control box 24 controls the above-ground water storage tank 8 to empty the circulating fresh water and reintroduce fresh water. When the salinity of the circulating fresh water is lower than 150 g / L~180 g / L, the concentration difference between the solid and liquid surfaces of salt crystals in the brine well is extremely large, the dissolution rate is fast, and the return water carries crystals strongly.

[0024] This invention employs a three-layer coaxial structure of "protective layer-sandwich tube-protective layer" for both the inner rotating well casing 3 and the outer rotating well casing 1. The protective layer is fixed, while the sandwich tube rotates via a drive mechanism and is supported by bearings. Its advantages include: a closed-loop flushing circuit. Fresh water is strictly confined to the closed loop formed by "outer rotating well casing 1-permeable filter layer 5-inner rotating well casing 3," cutting off the path for fresh water to invade the formation. This achieves fresh water flushing and unblocking of salt deposits in the brine well, significantly reducing salt layer erosion cavities caused by fresh water overflow, and addressing wellbore collapse at its source; dynamic anti-salt deposition and self-cleaning. Continuous relative shearing motion occurs between the rotating pipe wall and the crystalline particles or already deposited salt in the brine, effectively peeling and crushing salt crystals about to deposit on the pipe wall; optimized flow field and improved flushing efficiency. The closed flushing circuit introduces a strong eddy current effect and stirring action, enhancing the turbulent diffusion and convective shear stress between the flushing fluid and the surface of the salt deposits. Simultaneously, insoluble or crystalline particles flushed down are carried out of the well by the circulating fluid, preventing secondary settling and blockage at the well bottom or filter; protecting the original formation structure and maintaining wellbore stability. The fixed outer casing 101 is fixed to the well platform 2 at the top, serving as a permanent casing. It supports the wellbore and isolates the formation, preventing direct friction and disturbance between the rotating body and the fragile salt rock formation.

[0025] The above description is merely one embodiment of this utility model, and while it is quite specific and detailed, it should not be construed as limiting the scope of this utility model. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the appended claims.

Claims

1. A double-layer rotating brine well structure, characterized in that: The brine extraction well structure includes a well platform (2), a double-layer rotating well casing, a well casing rotation drive mechanism, and a bottom sand settling pipe (4). The well platform (2) is located on the ground. The double-layer rotating well casing includes an outer rotating well casing (1), an inner rotating well casing (3), and a permeable filter material layer (5) disposed between the inner and outer rotating well casings. The outer rotating well casing (1) includes an outer rotating pipe (100), an outer pipe protection pipe (101), and an outer pipe isolation net (102). The outer pipe protection pipe (101) includes two fixed... The outer pipe isolation net (102) includes two layers of filter screens disposed on the outer wall of the outer outer pipe protection pipe (101) and the inner wall of the inner outer pipe protection pipe (101). Corresponding outer pipe water permeable holes (103) are provided on the outer rotating pipe (100) and the outer pipe protection pipe (101). The inner rotating well pipe (3) includes an inner rotating pipe (300), an inner pipe protection pipe (301) and an inner pipe isolation net (302). The inner pipe protection pipe (301) includes two fixed pipes disposed on the inner and outer sides of the inner rotating pipe (300). The mesh (302) is set on the outer wall of the outer inner tube protection pipe (301), and corresponding inner tube water permeable holes (303) are provided on the inner rotating pipe (300) and the inner inner tube protection pipe (301); the lower ends of the outer rotating pipe (100) and the inner rotating pipe (300) are rotatably connected to the bottom sand-collecting pipe (4), and the pipe openings extend out of the well platform (2), with the pipe opening of the inner rotating pipe (300) being higher than that of the outer rotating pipe (100); the well pipe rotation drive mechanism includes an outer tube drive motor (20) and an inner tube drive motor (21), the outer tube drive... The motor (20) is connected to the outer rotating tube (100) through a rotating mechanism and controls the rotation of the outer rotating tube (100) so that the water permeable holes (103) of the outer rotating tube (100) and the outer tube protection tube (101) open correspondingly or close staggeredly; the inner tube drive motor (21) is connected to the inner rotating tube (300) through a rotating mechanism and controls the rotation of the inner rotating tube (300) so that the water permeable holes (303) of the inner rotating tube (300) and the inner tube protection tube (301) open correspondingly or close staggeredly.

2. The double-layer rotating brine well structure according to claim 1, characterized in that: The well pipe rotation drive mechanism also includes a support frame (19), and the outer pipe drive motor (20) and the inner pipe drive motor (21) are both fixed on the support frame (19); an outer gear (6) is provided at the wellhead of the outer rotating pipe (100), and an inner gear (7) is provided at the wellhead of the inner rotating pipe (300). The output shaft of the outer pipe drive motor (20) is fixedly connected to a first transmission gear (22), which meshes with the outer gear (6). The output shaft of the inner pipe drive motor (21) is fixedly connected to a second transmission gear (23), which meshes with the inner gear (7).

3. The double-layer rotating brine well structure according to claim 1, characterized in that: The bottom sand settling pipe (4) is a sand settling pipe cast with anti-corrosion cement, including two layers of steel pipes with smooth coating on the inner and outer surfaces and slag cement filled between the two layers of steel pipes; the bottoms of the two outer protective pipes (101) and the two inner protective pipes (301) are fixed to the top surface of the bottom sand settling pipe (4); the bottom of the outer rotating pipe (100) is rotatably connected to the bottom sand settling pipe (4) through the outer rotating well pipe bearing (104); the bottom of the inner rotating pipe (300) is rotatably connected to the bottom sand settling pipe (4) through the inner rotating well pipe bearing (304); the outer rotating well pipe bearing (104) and the inner rotating well pipe bearing (304) are both fixed to the top surface of the bottom sand settling pipe (4).

4. The double-layer rotating brine well structure according to claim 1, characterized in that: The outer rotating pipe (100), outer pipe protection pipe (101), inner rotating pipe (300) and inner pipe protection pipe (301) are all made of steel pipe with a wall thickness of 6mm to 8mm. The pipe wall is uniformly provided with water-permeable holes with a porosity of 12% to 16%. The outer pipe isolation net (102) and the inner pipe isolation net (302) are both made of metal filter net. The outer diameter of the outer rotating well pipe (1) is 700mm to 900mm, and the outer diameter of the inner rotating well pipe (3) is 500mm to 600mm.

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