Underground heat exchange device of V-shaped middle-deep layer buried pipe

Abstract

The invention provides a V-shaped medium-deep layer buried pipe underground heat exchange device which comprises a stratum, a ground heat exchanger, a first underground loop circulating pump and a second underground loop circulating pump, a water injection well is arranged on the left side in the stratum, a water outlet well is arranged on the right side in the stratum, and well bodies of the water injection well and the water outlet well are drilled according to a set track. The input end of the second underground loop circulating pump is communicated with the heat exchange pipe in the petroleum casing pipe located on the right side of the upper portion of the stratum, the structure is reasonable, practicability is good, the length of the horizontal section with the highest technical difficulty is greatly shortened through V-shaped butt joint, the drilling risk and the construction cost are reduced, and the construction efficiency is improved. The unique V-shaped structure concentrates the heat exchange process in the well bottom area with the highest ground temperature, the effective heat exchange area is greatly increased, an underground constant-temperature heat source is utilized, and the performance is stable.

Description

Technical Field

[0001] This invention is a V-shaped medium-deep underground heat exchange device with buried pipes, belonging to the field of building environment equipment technology. Background Technology

[0002] Heat pump technology, as a highly efficient energy supply method that extracts heat energy from a low-temperature heat source and releases it to a high-temperature heat source, is an important way to achieve the above-mentioned goals. Among various heat pump technologies, medium-deep ground source heat pump technology has received widespread attention in recent years due to its advantages such as high energy efficiency, no pollution, no influence from surface climate conditions, and minimal interference with the groundwater environment. This technology mainly exchanges heat with medium-deep rock and soil through an underground buried pipe heat exchanger system.

[0003] Currently, mainstream medium-deep underground pipe heat exchange systems mainly adopt coaxial sleeve or U-tube structures. While U-tube heat exchange wells can increase the heat extraction capacity of a single well by increasing the heat exchange area, they typically require drilling two deep wells and connecting them via a long horizontal section at extremely deep underground depths. This presents challenges such as extremely high drilling technical difficulty, high construction risk, and high initial investment costs, limiting the large-scale application of this technology. Coaxial sleeve heat exchange systems, on the other hand, have inherent drawbacks such as relatively low heat exchange efficiency and significant heat loss. Therefore, there is an urgent need for a V-shaped medium-deep underground pipe heat exchange device to address these problems. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a V-shaped medium-deep underground heat exchange device for buried pipes, thereby solving the problems mentioned in the background section. The present invention has a reasonable structure and good practicality. The V-shaped connection significantly shortens the length of the horizontal section, which is the most technically challenging part, reducing drilling risks and construction costs. The unique V-shaped structure concentrates the heat exchange process in the well bottom area with the highest ground temperature, greatly increasing the effective heat exchange area. It utilizes an underground constant-temperature heat source and has stable performance.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: a V-shaped medium-deep underground heat exchange device, comprising a stratum, a surface heat exchanger, a first underground loop circulation pump, and a second underground loop circulation pump. An injection well is located on the left side of the stratum, and an outlet well is located on the right side of the stratum. The injection well and the outlet well are drilled along a predetermined trajectory and intersect and connect at a target area at a predetermined underground depth, forming a V-shaped structure. Both the injection well and the outlet well are cemented using oil casing, and a heat exchange tube is installed inside the oil casing. A second pipe body is installed at the secondary inlet in the upper left corner of the surface heat exchanger, and a user loop circulation pump is installed at the other end of the second pipe body. The input end of the second underground loop circulation pump is connected to the heat exchange tube inside the oil casing located on the right side above the stratum. The output end of the second underground loop circulation pump is connected to the primary inlet in the upper right corner of the surface heat exchanger. The input end of the first underground loop circulation pump is connected to the primary outlet of the surface heat exchanger through a fourth pipe body, and a first pipe body 6 is installed at the output end of the first underground loop circulation pump.

[0006] Furthermore, two pillars are installed on the left side above the stratum, a water storage tank is installed above the two pillars, and an electrically controlled valve is installed below the water storage tank. The input end of the electrically controlled valve is connected to the inside of the water storage tank.

[0007] Furthermore, the output end of the electrically controlled valve is connected to the heat exchange tube inside the oil casing located on the left side above the formation via a third pipe body.

[0008] Furthermore, U-shaped connecting frames are respectively fitted onto the outer sides of the upper ends of the two oil casings, and square plates are welded to the left and right sides of the two U-shaped connecting frames, and multiple square plates are respectively connected to the formation by bolts.

[0009] Furthermore, the gaps between the two oil casings and the injection and output wells are filled with a cement slurry layer 18.

[0010] Furthermore, the ground heat exchanger has a secondary outlet at the lower right corner for installing building return water pipes.

[0011] Furthermore, a lower ring is fixedly connected to the center of the bottom surface of the water storage tank, and the central hole of the lower ring is concentrically set with the input end of the electric control valve. An upper ring is fixedly sleeved on the outer side of the lower end of the first pipe.

[0012] Furthermore, an upper sealing ring is fixed above the lower ring, and L-shaped grooves are provided at the left and right ends of the upper part of the lower ring, and positioning holes are provided at the front and rear ends of the upper part of the lower ring.

[0013] Furthermore, a lower sealing ring is fixed below the upper ring, and positioning pins are fixed at the front and rear ends below the upper ring, with the diameter of the positioning pins being smaller than the diameter of the positioning holes.

[0014] Furthermore, rectangular grooves are provided at the left and right ends below the upper ring, and circular receiving grooves are provided on the side of the two rectangular grooves near the positioning post. Magnetic rods are slidably installed on the inner walls of the two circular receiving grooves, and magnetic blocks with opposite magnetic properties to the magnetic rods are fixed to the inner walls of the two circular receiving grooves respectively.

[0015] Furthermore, L-shaped locking rods are fixedly connected to the opposite outer ends of the two magnetic rods, and handles are fixedly connected to the vertical ends of the two L-shaped locking rods on the side away from the positioning post.

[0016] Furthermore, springs are installed on the vertical ends of the two L-shaped clamps near the circular receiving groove, and the two springs are respectively sleeved on the outside of the two magnetic round rods. The other ends of the two springs are respectively fixedly connected to the inner wall of the rectangular groove.

[0017] The beneficial effects of this invention: The V-shaped medium-deep underground heat exchange device of this invention, due to the addition of a surface heat exchanger, water storage tank, user loop circulation pump, first underground loop circulation pump, first pipe body, second underground loop circulation pump, second pipe body, third pipe body, fourth pipe body, support column, electric control valve, oil casing, U-shaped socket frame, square plate, bolts, and cement grout layer, has shown through our design improvements and actual use that this device has a reasonable structure and good practicality. The V-shaped connection significantly shortens the length of the most technically challenging horizontal section, reducing drilling risks and construction costs. The unique V-shaped structure concentrates the heat exchange process in the well bottom area with the highest ground temperature, greatly increasing the effective heat exchange area, utilizing an underground constant temperature heat source, and exhibiting stable performance. Attached Figure Description

[0018] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0019] Figure 1 This is a three-dimensional schematic diagram of the structure of a V-shaped medium-deep underground pipe heat exchange device of the present invention, in which the ground heat exchanger is connected above a local stratum.

[0020] Figure 2 This is a three-dimensional schematic diagram of the ground heat exchanger structure of a V-shaped medium-deep underground pipe heat exchange device according to the present invention.

[0021] Figure 3 This is a three-dimensional schematic diagram of the connection structure between two U-shaped connecting frames and the local stratum of a V-shaped medium-deep buried pipe underground heat exchange device according to the present invention;

[0022] Figure 4 This is a three-dimensional cross-sectional view of the geological structure of a V-shaped medium-deep underground pipe heat exchange device according to the present invention.

[0023] Figure 5 This is a schematic diagram of the cross-sectional structure of the water storage tank of a V-shaped medium-deep buried pipe underground heat exchange device according to the present invention.

[0024] Figure 6 This is a schematic diagram of the first pipe body structure of a V-shaped medium-deep buried pipe underground heat exchange device according to the present invention.

[0025] Figure 7 This is a three-dimensional schematic diagram of the lower circular ring structure of a V-shaped medium-deep underground heat exchange device of the present invention;

[0026] Figure 8 This is a three-dimensional schematic diagram of the upper ring structure of a V-shaped medium-deep underground heat exchange device of the present invention;

[0027] Figure 9 This is a schematic diagram of the cross-sectional structure of the connection between the upper and lower rings of a V-shaped medium-deep underground heat exchange device according to the present invention.

[0028] Figure 10 This invention relates to a V-shaped medium-deep underground heat exchange device using buried pipes. Figure 4 A magnified 3D schematic diagram of the structure at point A;

[0029] Figure 11 This is a three-dimensional schematic diagram of the ground heat exchanger of a V-shaped medium-deep underground pipe heat exchange device of the present invention, which is connected above the overall stratum.

[0030] Figure 12 This invention relates to a V-shaped medium-deep underground heat exchange device using buried pipes. Figure 4 Enlarged 3D schematic diagram of the structure at point B.

[0031] In the diagram: 1-stratum, 2-surface heat exchanger, 3-water storage tank, 4-user loop circulation pump, 5-first underground loop circulation pump, 6-first pipe body, 7-second underground loop circulation pump, 8-second pipe body, 9-third pipe body, 10-fourth pipe body, 11-support column, 12-electric control valve, 13-oil casing, 14-U-shaped socket bracket, 15-square plate, 16-bolt, 17-injection well, 18-cement slurry layer, 19-outlet well, 20-handle, 21-lower ring, 22-lower sealing ring, 23-L-shaped groove, 24-rectangular groove, 25-upper ring, 26-positioning column, 27-upper sealing ring, 28-L-shaped rod, 29-circular receiving groove, 30-magnetic block, 31-magnetic rod, 32-spring, 33-positioning hole. Detailed Implementation

[0032] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0033] Please see Figures 1-12 This invention provides a technical solution: a V-shaped medium-deep underground heat exchange device, comprising a formation 1, a surface heat exchanger 2, a first underground loop circulation pump 5, and a second underground loop circulation pump 7. A water injection well 17 is located on the left side of the formation 1, and a water outlet well 19 is located on the right side of the formation 1. The wellbores of the water injection well 17 and the water outlet well 19 are drilled along a predetermined trajectory and intersect and connect at a target area at a predetermined underground depth, forming a V-shaped structure. Both the water injection well 17 and the water outlet well 19 are cemented using oil casing 13, and a heat exchange tube is installed inside the oil casing 13. A second pipe body 8 is installed at the secondary side inlet at the upper left corner of the surface heat exchanger 2, and a user loop circulation pump is installed at the other end of the second pipe body 8. The input end of the second underground loop circulation pump 7 is connected to the heat exchange tube inside the oil casing 13 located on the right side above the formation 1. The output end of the second underground loop circulation pump 7 is connected to the primary side inlet at the upper right corner of the surface heat exchanger 2. The input end of the first underground loop circulation pump 5 is connected to the primary side outlet of the surface heat exchanger 2 through the fourth pipe body 10. The output end of the first underground loop circulation pump 5 is equipped with the first pipe body 6. This design solves the problems of extremely difficult drilling technology, high construction risk, and high initial investment cost in traditional technology, which limit the large-scale promotion and application of this technology. On the other hand, the coaxial casing heat exchange system has the inherent disadvantages of relatively low heat exchange efficiency and large heat loss.

[0034] As a first embodiment of the present invention: Two support pillars 11 are installed on the left side above the formation 1. A water storage tank 3 is installed above the two support pillars 11. An electrically controlled valve 12 is installed below the water storage tank 3. The input end of the electrically controlled valve 12 is connected to the inside of the water storage tank 3, and the output end of the electrically controlled valve 12 is connected to the oil casing 13 located on the left side above the formation 1 through a third pipe body 9. By connecting the output end of the electrically controlled valve 12 to the heat exchange tube inside the oil casing 13 located on the left side above the formation 1 through the third pipe body 9, it is convenient to inject low-temperature circulating medium into the V-shaped structure formed by the two oil casings 13. U-shaped connecting frames 14 are respectively sleeved on the outer side of the upper end of the two oil casings 13. Square plates 15 are welded to the left and right sides of the two U-shaped connecting frames 14 respectively. Multiple square plates 15 are respectively connected to the formation 1 by bolts 16. The two U-shaped connecting frames 14 are respectively set to enhance the stability of the two oil casings 13. The gaps between the two oil casings 13 and the water injection well 17 and the water outlet well 19 are all filled with a cement grout layer 18. By setting the cement grout layer 18, the stability of the two oil casings 13 can be further improved. The lower right corner of the ground heat exchanger 2 is provided with a secondary side outlet for installing the building return water pipe.

[0035] A lower ring 21 is fixedly connected to the center of the bottom surface of the water storage tank 3. The central hole of the lower ring 21 is concentrically set with the input end of the solenoid valve 12. An upper ring 25 is fixedly sleeved on the outer side of the lower end of the first pipe body 6. Through the cooperation of the lower ring 21 and the upper ring 25, the first pipe body 6 can be quickly connected. By setting the central hole of the lower ring 21 concentrically with the input end of the solenoid valve 12, the liquid inside the first pipe body 6 can smoothly enter the input end of the solenoid valve 12. An upper sealing ring 27 is fixed above the lower ring 21. L-shaped grooves 23 are respectively provided at the left and right ends of the upper part of the lower ring 21, and positioning holes 33 are respectively provided at the front and rear ends of the upper part of the lower ring 21. A lower sealing ring 22 is fixed below the upper ring 25. Positioning pins 26 are fixed at the front and rear ends of the lower ring 25, and the diameter of the positioning pins 26 is smaller than the diameter of the positioning hole 33. By setting the upper sealing ring 27 and the lower sealing ring 22, and by their close fit, the sealing performance at the joint between the lower ring 21 and the upper ring 25 can be improved. By setting the positioning pins 26 and the positioning hole 33, and by their insertion fit, the precise docking between the lower ring 21 and the upper ring 25 can be achieved.

[0036] Rectangular grooves 24 are provided at the left and right ends below the upper ring 25. Circular receiving grooves 29 are provided on the side of each rectangular groove 24 near the positioning post 26. Magnetic rods 31 are slidably installed on the inner walls of each circular receiving groove 29. Magnetic blocks 30 with opposite magnetic properties to the magnetic rods 31 are fixedly connected to the inner walls of each circular receiving groove 29. By setting up the magnetic rods 31 and the magnetic blocks 30, and through their magnetic attraction, the magnetic rods 31 can be temporarily limited. L-shaped locking rods 28 are fixedly connected to the outer ends of the two magnetic rods 31. Handles 20 are fixedly connected to the vertical ends of the two L-shaped locking rods 28 away from the positioning post 26. The cooperation between the L-shaped locking rods 28 and the L-shaped grooves 23 facilitates a secure connection between the lower ring 21 and the upper ring 25. The handles 20 facilitate pulling the L-shaped locking rods 28. Two L-shaped locking rods 28 are each fitted with a spring 32 on the side of their vertical ends near the circular receiving groove 29. The two springs 32 are respectively sleeved on the outside of the two magnetic round rods 31. The other ends of the two springs 32 are respectively fixedly connected to the inner wall of the rectangular groove 24. By setting the springs 32, it is easy to reset the L-shaped locking rods 28.

[0037] As a second embodiment of the present invention: In use, the first tube 6 can be separated from the input end of the solenoid valve 12. Specifically, by using the handle 20, the two L-shaped levers 28 are moved sequentially, causing the two L-shaped levers 28 to move towards the positioning post 26. At this time, the two springs 32 are compressed, and the two magnetic rods 31 move inside the corresponding circular receiving grooves 29. When the two magnetic rods 31 contact the two magnetic blocks 30 respectively, the two magnetic rods 31 and the two magnetic blocks 30 are attracted together, thereby overcoming the elastic force of the two springs 32. At this time, the two L-shaped levers 28 are moved towards the positioning post 26. The horizontal end of the L-shaped locking rod 28 is completely disengaged from the horizontal ends of the two L-shaped locking slots 23. Then, the first tube 6 is pulled upwards until the two positioning pins 26 are completely disengaged from the two positioning holes 33, thus completing the separation of the lower ring 21 from the upper ring 25. Next, liquid medium is injected into the input end of the solenoid valve 12. Then, the first tube 6 is firmly connected to the input end of the solenoid valve 12. Specifically, the connection is performed so that the two positioning pins 26 are fully inserted into the two positioning holes 33. At this point, the upper end of the lower sealing ring 22 is tightly fitted with the lower end of the upper sealing ring 27, and the two L-shaped locking rods 28 are inserted into the two L-shaped locking slots 23. Inside, the horizontal ends of the two L-shaped locking rods 28 are aligned with the horizontal ends of the two L-shaped locking slots 23. Then, the two handles 20 are pulled in sequence, causing the two magnetic rods 31 to move and separate from the magnetic block 30. At this time, due to the reset of the two springs 32, the horizontal ends of the two L-shaped locking rods 28 are inserted into the horizontal ends of the two L-shaped locking slots 23, thus completing the docking of the lower ring 21 and the upper ring 25. Then, the liquid medium will flow into the heat exchange tube inside the oil casing 13 in the water injection well 17, and start the second underground loop circulation pump 7, which will drive the liquid medium from the outlet well 19 to the surface heat exchanger. In the heat exchanger 2, the ground heat exchanger 2 can exchange heat with the liquid medium. After the heat exchange is completed, the liquid medium will re-enter the water injection well 17 under the action of the first underground loop circulation pump 5. The user loop circulation pump 4, together with the second pipe body 8, can receive the water source that needs to be heated and heat it through the ground heat exchanger 2. Finally, it is discharged through the secondary side outlet at the lower right corner of the ground heat exchanger 2. Before the water source is discharged, the building return water pipe needs to be connected to the secondary side outlet at the lower right corner of the ground heat exchanger 2, and then the hot water is transported to the residential area of ​​the town for people to use through the building return water pipe.

[0038] All standard parts used in this invention can be purchased from the market, and irregular parts can be customized according to the description and drawings. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts and equipment adopt conventional models in the prior art, and the circuit connection adopts conventional connection methods in the prior art, which will not be described in detail here. The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0039] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0040] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A V-shaped medium-deep underground heat exchange device, comprising a stratum (1), a surface heat exchanger (2), a first underground loop circulation pump (5), and a second underground loop circulation pump (7), characterized in that: A water injection well (17) is provided on the left side of the stratum (1), and a water outlet well (19) is provided on the right side of the stratum (1). The wellbore of the water injection well (17) and the water outlet well (19) are drilled along a set trajectory and intersect and connect in a target area at a predetermined depth underground to form a V-shaped structure. Both the water injection well (17) and the water outlet well (19) are cemented using oil casing (13), and the oil casing (13) is equipped with a heat exchange tube inside. The secondary inlet at the upper left corner of the ground heat exchanger (2) is equipped with a second pipe body (8), and the other end of the second pipe body (8) is equipped with a user loop circulation pump (4). The input end of the second underground loop circulation pump (7) is connected to the heat exchange tube inside the oil casing (13) located on the right side above the stratum (1). The output end of the second underground loop circulation pump (7) is connected to the primary inlet at the upper right corner of the ground heat exchanger (2). The input end of the first underground loop circulation pump (5) is connected to the primary outlet of the ground heat exchanger (2) through a fourth pipe body (10). The output end of the first underground loop circulation pump (5) is equipped with a first pipe body (6).

2. The V-shaped medium-deep underground heat exchange device according to claim 1, characterized in that: Two pillars (11) are installed on the upper left end of the stratum (1). A water storage tank (3) is installed above the two pillars (11). An electric control valve (12) is installed below the water storage tank (3). The input end of the electric control valve (12) is connected to the inside of the water storage tank (3).

3. The V-shaped medium-deep underground heat exchange device according to claim 2, characterized in that: The output end of the electrically controlled valve (12) is connected to the heat exchange tube inside the oil casing (13) located on the left side above the formation (1) through the third pipe body (9).

4. The V-shaped medium-deep underground heat exchange device according to claim 1, characterized in that: Two oil casings (13) are respectively fitted with U-shaped socket brackets (14) on the outer side of their upper ends. Square plates (15) are welded to the left and right sides of the two U-shaped socket brackets (14). Multiple square plates (15) are respectively fixedly connected to the formation (1) by bolts (16).

5. The V-shaped medium-deep underground heat exchange device according to claim 1, characterized in that: The gaps between the two oil casings (13) and the injection well (17) and the outlet well (19) are filled with cement slurry (18).

6. The V-shaped medium-deep underground heat exchange device according to claim 1, characterized in that: The ground heat exchanger (2) has a secondary outlet at the lower right corner for installing building return water pipes.

7. The V-shaped medium-deep underground heat exchange device according to claim 1, characterized in that: A lower ring (21) is fixedly connected to the middle of the bottom surface of the water storage tank (3). The central hole of the lower ring (21) is concentrically set with the input end of the electric control valve (12). An upper ring (25) is fixedly sleeved on the outer side of the lower end of the first pipe body (6).

8. The V-shaped medium-deep underground heat exchange device according to claim 7, characterized in that: An upper sealing ring (27) is fixed above the lower ring (21). L-shaped grooves (23) are provided at the left and right ends above the lower ring (21). Positioning holes (33) are provided at the front and rear ends above the lower ring (21).

9. A V-shaped medium-deep underground heat exchange device according to claim 7, characterized in that: A lower sealing ring (22) is fixed below the upper ring (25). Positioning posts (26) are fixed at the front and rear ends below the upper ring (25), and the diameter of the positioning posts (26) is smaller than the diameter of the positioning hole (33). Rectangular grooves (24) are provided at the left and right ends below the upper ring (25). Circular receiving grooves (29) are provided on the side of each of the two rectangular grooves (24) near the positioning posts (26). Magnetic rods (31) are slidably installed on the inner walls of each of the two circular receiving grooves (29). The inner walls of the two circular receiving grooves (29) are respectively fixed with... A magnetic block (30) with opposite magnetism to the magnetic rod (31) is provided. L-shaped locking rods (28) are fixed to the outer ends of the two magnetic rods (31). A handle (20) is fixedly connected to the side of the vertical end of the two L-shaped locking rods (28) away from the positioning post (26). A spring (32) is installed on the side of the vertical end of the two L-shaped locking rods (28) near the circular receiving groove (29). The two springs (32) are respectively sleeved on the outside of the two magnetic rods (31). The other end of the two springs (32) is fixedly connected to the inner wall of the rectangular groove (24).

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