Geothermal single well heat exchange system

Abstract

The invention belongs to the field of geothermal systems, and discloses a geothermal single well heat exchange system which comprises a sleeve on the outer side and a heat exchange system body wrapped in the sleeve, and a cleaning assembly used for cleaning the inner wall of the body is further arranged in the body. The cleaning assembly comprises a movable plate and a cleaning mechanism, the movable plate is annularly distributed and internally provided with a hollow structure, the cleaning mechanism is connected with the movable plate, the cleaning mechanism moves in the body along with the movable plate, and the inner wall of the body is cleaned through scraping of the cleaning mechanism and the inner wall of the body. According to the geothermal single well heat exchange system, the cleaning mechanism is additionally arranged in the heat exchange system, meanwhile, the cleaning mechanism can generate driving force according to flowing of water flow and achieve multi-direction cleaning, the geothermal single well heat exchange system is suitable for automatic cleaning of the interior of the large-diameter heat exchange system distributed in a long straight line, and the water flow conveying effect after the heat exchange system is used for a long time is improved; and a large amount of residual scale is effectively avoided.

Description

Technical Field

[0001] The invention relates to the technical field of geothermal systems, and in particular to a geothermal single-well heat exchange system. Background Art

[0002] In order to reduce the use of coal and electricity resources and provide hot water for centralized heating needs such as residential buildings, the prior art mostly adopts a single-well geothermal heat exchange system to achieve stability and energy saving of residential heating. For example, in the prior art, there is a heat exchange casing device and a geothermal single-well system for efficiently exploiting geothermal resources with a publication number of CN112815557B. The heat exchange casing device is arranged in the target heat reservoir section, including a steel casing and a high-efficiency heat exchange component. The steel casing is the main structure, and the steel casing is provided with an original hole position of the heat exchange component for installing the high-efficiency heat exchange component; the high-efficiency heat exchange component is made of a material with a higher thermal conductivity than steel, is adapted to be installed in the original hole position of the heat exchange component, and is sealed; the geothermal single-well system includes an outer casing and an inner oil pipe, the annulus formed between the casing and the oil pipe is used as an injection well, and the oil pipe is used as a production well. The casing is a segmented structure, and the section located on the non-target heat reservoir adopts an ordinary casing made of steel, and the section located on the target heat reservoir adopts a heat exchange casing device. The high-efficiency heat exchange sleeve device of the invention is located in the target heat reservoir section and is applied to geothermal resource exploitation to increase heat exchange efficiency and improve the utilization rate of geothermal resources; Another example is a geothermal single-well downhole heat exchanger and automatic oil return heat exchange system with publication number CN117704657A. Two uniform velocity plates are arranged inside the plate and shell heat exchanger, and through holes of different sizes are arranged on the uniform velocity plates, so as to ensure that the fluid flow rate entering each group of plates is the same and the flow rate is equal. It is used to solve the technical problem of uneven flow distribution between different plates inside the existing plate and shell heat exchanger, which causes the heat exchange performance to decrease. At the same time, in order to further reduce the power consumption of the geothermal single-well heat exchange system and thus increase the heat extraction power, an automatic oil return unit is arranged in the heat exchange system to solve the oil leakage problem of the compressor in the heat exchange system. The present invention meets the requirement of "taking heat without taking water" and can improve the heat exchange efficiency of the heat exchanger. At the same time, it solves the problem of compressor damage caused by insufficient lubricating oil. The automatic oil return unit does not require manual intervention, which reduces the cost of manual maintenance, greatly reduces the maintenance workload, and enhances the reliability of the unit. The implementation of the above-mentioned prior art solutions requires a channel for fluid flow in the geothermal system. Due to the antifreeze and other properties of the fluid itself, a variety of additives are added to increase the antifreeze and other effects. This causes scaling to easily form in places where the system is in contact with the fluid for a long time. The structure of this type of system is generally long and it is not convenient to empty and clean the internal water. Therefore, regular maintenance and cleaning of the heat exchange system will be very troublesome. Summary of the invention

[0003] The object of the present invention is to provide a geothermal single-well heat exchange system to solve the problem that the implementation of the technical solution proposed in the above-mentioned background technology requires a channel for the flow of fluid in the geothermal system. Due to the antifreeze and other properties of the fluid itself, a variety of additives are added to increase the antifreeze and other effects. This leads to the problem that scale is easily generated in places where the system is in contact with the fluid for a long time. The structure of this type of system is generally long and it is not convenient to empty and clean the internal water. Therefore, regular maintenance and pipeline cleaning work will be very troublesome.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a geothermal single-well heat exchange system, comprising an outer casing and a heat exchange system body wrapped therein, wherein a cleaning component for cleaning the inner wall of the body is also arranged in the body, the cleaning component comprises a movable plate which is distributed in an annular manner and has a hollow structure inside, and a cleaning mechanism connected to the movable plate, wherein the cleaning mechanism moves in the body following the movable plate, and cleans the inner wall of the body by scraping the cleaning mechanism against the inner wall of the body, and the movable plate moves upward following the dynamic water flow in the body, and moves downward when the water flow is stationary.

[0005] As a further preferred solution, a rotating mechanism is installed on the movable plate, and the rotating mechanism is used to drive the cleaning mechanism to rotate synchronously with the inner wall of the cleaning body while following the vertical movement of the movable plate.

[0006] As a further preferred solution, the rotating mechanism includes a paddle and a main shaft for mounting the paddle, the main shaft is vertically distributed and rotatably mounted on the axis of the movable plate, and the bottom end of the main shaft is connected to the cleaning mechanism.

[0007] As a further preferred solution, rollers are embedded at the edges of the movable plate, and the rollers are used to limit the movement of the movable plate in a direction perpendicular to the axis of the rollers and reduce the movement resistance of the movable plate.

[0008] As a further preferred solution, a receiving groove is also provided on the inner wall of the top end of the main body, the inner diameter of the receiving groove is larger than the average inner diameter of the main body, and after the roller moves to the height of the receiving groove, it pops out from the inside of the movable plate via the elastic member and rests in the receiving groove to stop the movable plate from moving as a whole, and at the same time, an electric-controlled push rod is installed at the receiving groove to squeeze the roller back into the movable plate when the water stops flowing.

[0009] As a further preferred solution, the cleaning mechanism consists of a complete annular structure, that is, a ring body with rubber strips or bristles on the outer surface.

[0010] As a further preferred solution, the cleaning mechanism comprises a plurality of cleaning plates which are distributed vertically or obliquely and adjacent to each other without being closed.

[0011] As a further preferred solution, the root of the blade is rotatably mounted on the side wall of the main shaft through an axis, and the inner end of the shaft is provided with a first bevel tooth which is vertically distributed and located in the internal space of the main shaft, and the first bevel tooth is meshed with a second bevel tooth which is horizontally distributed and mounted on the vertical cylinder, and the vertical cylinder rotatably mounted inside the main shaft is connected to a driving mechanism, and the driving mechanism is used to drive the blade to deflect after the main shaft moves upward and touches the top.

[0012] As a further preferred solution, the driving mechanism includes a top plate located at the top of the main shaft, the lower end surface of the top plate is fixedly connected to the top of the vertical rod, the bottom end of the vertical rod slides through the top wall of the main shaft and is installed in the main shaft through spring elastic sliding, and at the same time, a plurality of guide rods distributed at equal angles are installed on the surface of the vertical rod, the end of the guide rod slides and fits in the guide groove, and the guide groove includes a vertical groove and an oblique groove connected end to end.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: the geothermal single well heat exchange system is provided with a cleaning mechanism inside the heat exchange system, and the cleaning mechanism can generate driving force according to the flow of water and realize multi-directional cleaning, which is suitable for the internal automatic cleaning of such a large diameter heat exchange system with a long straight line distribution, improves the water flow conveying effect of the heat exchange system after long-term use, and effectively avoids a large amount of residual scale, as shown in the following content: 1. The use of movable plates and cleaning mechanisms in the heat exchange system can cooperate with the drive of water flow to realize the up and down movement of the cleaning mechanism as a whole inside the heat exchange system, so as to effectively clean the inner wall of the heat exchange system by using the auxiliary structure of the heat exchange system; Furthermore, the use of rollers can ensure the stability of the cleaning mechanism as a whole in the vertical direction of the heat exchange system. The receiving groove provided in the heat exchange system itself can also be used to temporarily store the cleaning mechanism and the movable plate, thereby avoiding the repeated up and down movement of the cleaning mechanism due to the change in the size of the water flow in the working process of the heat exchange system, thereby increasing the stability of the structural operation. 2. The structural design of multiple sets of disconnected cleaning plates can effectively reduce the resistance of the cleaning components during movement inside the heat exchange system, and can use the multi-dimensional rotation of the cleaning plates to more fully scrape the inner wall of the heat exchange system to avoid cleaning dead corners; Furthermore, the structural design of multiple sets of bevel teeth, combined with guide rods and guide grooves, can achieve automatic adjustment of the inclination direction of the blades by utilizing the extrusion force between the top wall of the heat exchange system or the additional protruding structure and the top plate when the cleaning mechanism and the movable plate are moving upward and move to the end position, so that the direction of the blades in an up and down movement process is the same, but the change in the vertical movement direction is utilized to achieve synchronous rotation of the cleaning mechanism for dead-angle cleaning, and no participation of electronic control equipment is required, which is more in line with the requirements of the internal working environment of the heat exchange system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention; Figure 2 It is a schematic diagram of the structure of the movable plate of the present invention; Figure 3 This is a schematic diagram of the main structure of the second embodiment of the present invention; Figure 4 This is a schematic diagram of the elastic member distribution structure of the present invention; Figure 5 This is a schematic diagram of a cleaning mechanism according to Embodiment 3 of the present invention; Figure 6 This is a schematic diagram of the cleaning plate distribution structure of the present invention; Figure 7 This is a schematic diagram of the bevel gear distribution structure of the present invention; Figure 8 This is a schematic diagram of the internal structure of the vertical tube of the present invention; Fig. 9 It is a schematic diagram of the blade deflection after the vertical rod of the present invention moves downward.

[0015] In the figure: 1, body; 2, sleeve; 3, movable plate; 4, main shaft; 5, blade; 6, roller; 7, ring body; 8, receiving groove; 9, elastic member; 10, electric control push rod; 11, cleaning plate; 12, first bevel gear; 13, second bevel gear; 14, vertical cylinder; 15, vertical rod; 16, top plate; 17, guide rod; 18, inclined groove; 19, vertical groove. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] See also Figure 1-Figure 9 , the present invention provides the following technical solutions: Embodiment 1: In this embodiment, in order to fully solve the technical problems existing in the prior art, the following is disclosed: Figure 1-Figure 2The scheme shown includes an outer sleeve 2 and a heat exchange system body 1 wrapped therein, wherein the body 1 is also provided with a cleaning component for cleaning the inner wall of the body 1, the cleaning component includes a movable plate 3 which is distributed in an annular manner and has a hollow structure inside, and a cleaning mechanism connected to the movable plate 3, wherein the cleaning mechanism moves in the body 1 following the movable plate 3, and cleans the inner wall of the body 1 by scraping the cleaning mechanism and the inner wall of the body 1, and the movable plate 3 moves upward following the dynamic water flow in the body 1 and moves downward when the water flow is stationary, a rotating mechanism is installed on the movable plate 3, and the rotating mechanism is used to drive the cleaning mechanism to synchronously rotate and clean the inner wall of the body 1 while following the vertical movement of the movable plate 3, the rotating mechanism includes a paddle 5 and a main shaft 4 for installing the paddle 5, the main shaft 4 is vertically distributed and rotatably installed on the axis of the movable plate 3, and the bottom end of the main shaft 4 is connected to the cleaning mechanism, and the key points of this scheme are reflected When using the driving force generated by the flow of water itself to clean the inner wall of the heat exchange system, the water flows from top to bottom through the space between the sleeve 2 and the main body 1, and flows from bottom to top along the inside of the main body 1 after heat exchange. In this process, due to the driving force generated by the flow of water itself, the movable plate 3 will move upward as a whole. Although the movable plate 3 is a hardware structure, it has a certain buoyancy due to its internal hollow structure. Although it will be at the bottom of the main body 1 in a static state, it will float up with the water flow after the impact of the water flow. During this floating process, the cleaning mechanism will clean the main body 1 by scraping the inner wall of the main body 1 in the vertical direction. At the same time, since the water will also pass through the movable plate 3 and flow out from the output end of the insulation tube, the water flow will impact the blade 5, generate driving force and drive the main shaft 4 to rotate, thereby driving the cleaning mechanism to rotate synchronously and produce a cleaning effect.

[0018] Embodiment 2: In this embodiment, a more stable solution for maintaining the movable plate 3 to move is further disclosed. For details, please refer to Figure 3 as well as Figure 4 A roller 6 is inlaid at the edge of the movable plate 3. The roller 6 is used to limit the movement of the movable plate 3 in a direction perpendicular to the axis of the roller 6 and reduce the movement resistance of the movable plate 3. A receiving groove 8 is also provided on the inner wall of the top end of the body 1. The inner diameter of the receiving groove 8 is larger than the average inner diameter of the body 1. After the roller 6 moves to the height of the receiving groove 8, it pops out from the inside of the movable plate 3 through the elastic member 9 and rests in the receiving groove 8 to stop the movable plate 3 from moving as a whole. At the same time, an electric control push rod 10 is installed at the receiving groove 8 to squeeze the roller 6 back into the movable plate 3 when the water stops flowing. The main purpose of adopting the above scheme is to improve the stability of the movable plate 3 in the vertical direction.

[0019] The cleaning mechanism consists of a complete annular structure, that is, a ring body 7 with rubber strips or bristles on the outer surface.

[0020] Embodiment 3: The cleaning mechanism comprises a plurality of cleaning plates 11 which are vertically or obliquely distributed and adjacent to each other but not closed. In this embodiment, a scheme different from the above-mentioned embodiment is adopted because the closed-loop or open-loop rubber strip structure in the transmission scraping heat exchange system inner wall scheme will cause the overall movement resistance of the device inside the insulation pipe to be large, and after cleaning, the dirt separated from the inner wall of the pipe is easy to stay near the rubber strip or follow the movement of the rubber strip and then adhere to other areas. Therefore, in order to solve this problem, the embodiment disclosed in this embodiment is as follows Figure 5-Figure 6 The solution shown is to replace the closed-loop cleaning mechanism with an open-loop cleaning mechanism. Although the cleaning mechanism does not completely cover the lateral surface area of ​​the inner wall of the heat exchange system under normal conditions, the present device also discloses the following solution for increasing the steering of the cleaning mechanism, and this solution also does not require electric drive. Please refer to the following content for details.

[0021] The content disclosed in this scheme is the content of adding the cleaning mechanism steering mentioned in the above scheme. The specific principle is referenced to Figure 7-Figure 9The root of the blade 5 is rotatably mounted on the side wall of the main shaft 4 through an axis, and the inner end of the axis is equipped with a first bevel gear 12 which is vertically distributed and located in the internal space of the main shaft 4. The first bevel gear 12 is meshed with a second bevel gear 13 which is horizontally distributed and mounted on a vertical cylinder 14. The vertical cylinder 14 which is rotatably mounted inside the main shaft 4 is connected to a driving mechanism. The driving mechanism is used to drive the blade 5 to deflect after the main shaft 4 moves upward and touches the top. The driving mechanism includes a top plate 16 located at the top of the main shaft 4. The lower end of the top plate 16 is The top of the vertical rod 15 is fixedly connected to the top of the vertical rod 15, and the bottom end of the vertical rod 15 slides through the top wall of the main shaft 4 and is installed in the main shaft 4 through the elastic sliding of the spring. At the same time, a plurality of guide rods 17 with equal angles are installed on the surface of the vertical rod 15. The ends of the guide rods 17 slide and fit in the guide grooves. The guide grooves include vertical grooves 19 and inclined grooves 18 connected end to end. When the device as a whole moves upward in the heat exchange system, according to the initial inclination angle of the blade 5, the clockwise rotation angle generated by the impact of the water flow will drive the cleaning The cleaning mechanism rotates in the same direction, and when the device moves upward to the maximum distance and touches the top, the top plate 16 will be subjected to force and guide the vertical rod 15 to move downward. At this time, the guide rod 17 will move along the inclined groove 18 and guide the vertical cylinder 14 to rotate. At the same time, through the rotation of the mutually meshing bevel teeth, the deflection direction of the blade 5 will be synchronously deflected. When the heat exchange system is shut down normally and the water stops flowing, the movable plate 3 moves downward due to the influence of gravity. At this time, the vertical rod 15 will drive the guide rod 17 to move along the vertical groove 19. Therefore, in this state, the blade 5 will not rotate back to the initial state unless the top plate 16 is squeezed again. Therefore, in a complete movement process: that is, the movable plate 3 moves up and then down, the direction of the cleaning mechanism is unchanged, but because the direction of downward movement and upward movement is the same, the cleaning mechanism has different action surfaces on the inner wall of the heat exchange system during the upward and downward movement, which means that while avoiding the existence of cleaning dead corners, the running resistance of the cleaning mechanism is greatly reduced, the use effect is better, and the use effect of the insulation pipe can be effectively guaranteed.

[0022] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A geothermal single well heat exchange system, comprising an outer casing (2) and a heat exchange system body (1) wrapped therein, wherein the body (1) is further provided with a cleaning component for cleaning the inner wall of the body (1), characterized in that: The cleaning component comprises a movable plate (3) which is distributed in an annular manner and has a hollow structure inside, and a cleaning mechanism connected to the movable plate (3), wherein the cleaning mechanism moves in the body (1) following the movable plate (3), and cleans the inner wall of the body (1) by scraping the cleaning mechanism against the inner wall of the body (1), and the movable plate (3) moves upward following the dynamic water flow in the body (1) and moves downward when the water flow is stationary.

2. A geothermal single well heat exchange system according to claim 1, characterized in that: A rotating mechanism is installed on the movable plate (3), and the rotating mechanism is used to drive the cleaning mechanism to rotate synchronously with the inner wall of the cleaning body (1) while following the vertical movement of the movable plate (3).

3. A geothermal single well heat exchange system according to claim 2, characterized in that: The rotating mechanism comprises a paddle (5) and a main shaft (4) for mounting the paddle (5). The main shaft (4) is vertically distributed and rotatably mounted on the axis of the movable plate (3), and the bottom end of the main shaft (4) is connected to the cleaning mechanism.

4. A geothermal single well heat exchange system according to claim 3, characterized in that: A roller (6) is inlaid at the edge of the movable plate (3), and the roller (6) is used to limit the movement of the movable plate (3) along a direction perpendicular to the axis of the roller (6) and to reduce the movement resistance of the movable plate (3).

5. A geothermal single well heat exchange system according to claim 4, characterized in that: The inner wall at the top end of the body (1) is also provided with a receiving groove (8), the inner diameter of which is larger than the average inner diameter of the body (1), and after the roller (6) moves to the height of the receiving groove (8), it pops out from the inside of the movable plate (3) via the elastic member (9) and rests in the receiving groove (8) so that the movable plate (3) as a whole stops moving. At the same time, an electric control push rod (10) is installed at the receiving groove (8) for squeezing the roller (6) back into the movable plate (3) when the water stops flowing.

6. A geothermal single well heat exchange system according to any one of claims 1 to 5, characterized in that: The cleaning mechanism is composed of a complete annular structure, that is, a ring body (7) with a rubber strip or bristles on the outer surface.

7. A geothermal single well heat exchange system according to any one of claims 3 to 5, characterized in that: The cleaning mechanism comprises a plurality of cleaning plates (11) which are distributed vertically or obliquely and adjacent to each other without being closed.

8. A geothermal single well heat exchange system according to claim 7, characterized in that: The root of the blade (5) is rotatably mounted on the side wall of the main shaft (4) via a shaft, and the inner end of the shaft is mounted with a first bevel tooth (12) which is vertically distributed and located in the internal space of the main shaft (4), and the first bevel tooth (12) is meshed with a second bevel tooth (13) which is mounted on a vertical cylinder (14) and is horizontally distributed, and the vertical cylinder (14) rotatably mounted inside the main shaft (4) is connected to a driving mechanism, and the driving mechanism is used to drive the blade (5) to deflect after the main shaft (4) moves upward and touches the top.

9. A geothermal single well heat exchange system according to claim 8, characterized in that: The driving mechanism comprises a top plate (16) located at the top end of the main shaft (4), the lower end surface of the top plate (16) is fixedly connected to the top end of the vertical rod (15), the bottom end of the vertical rod (15) slides through the top wall of the main shaft (4) and is elastically slidably installed in the main shaft (4) through a spring, and a plurality of guide rods (17) distributed at equal angles are installed on the surface of the vertical rod (15), the ends of the guide rods (17) are slidably fitted in the guide grooves, and the guide grooves comprise a vertical groove (19) and an inclined groove (18) connected end to end.

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