Low-temperature geothermal energy extraction device and method

Abstract

The present invention discloses a low-temperature geothermal energy extraction device and method, which relate to the field of geothermal energy technology, wherein the low-temperature geothermal energy extraction device includes a heat exchange unit, a heat extraction pipe group, a heat exchange pipe group, and a control unit; the heat exchange unit includes a heat exchange tank and multiple heat exchange columns, and the heat exchange columns are provided with an upper partition, a lower partition, an adjustment shaft and a drive component. The upper partition, the lower partition and the inner wall of the heat exchange column are surrounded to form a heat exchange chamber, and the adjustment shaft is arranged in the heat exchange chamber. A plurality of partition plates are arranged along the peripheral side wall of the adjustment shaft. The plurality of partition plates divide the heat exchange chamber into a plurality of fan-shaped heat exchange areas. The drive component drives the adjustment shaft to rotate. A plurality of detection ports are opened on the side wall of the heat exchange column, each detection port is connected to a fan-shaped heat exchange area, and a temperature difference power generation plate is arranged in each detection port; the technical solution provided by the present invention can improve the extraction efficiency of geothermal energy.

Description

Technical Field

[0001] The present invention relates to the field of geothermal energy technology, and in particular to a low-temperature geothermal energy extraction device and method. Background Art

[0002] As a renewable energy source with abundant reserves, geothermal energy's development and utilization are crucial for optimizing the energy mix. Low-temperature geothermal energy (typically temperatures ≤150°C) is widely distributed from the shallow crust to strata thousands of meters deep. Heat is collected by drilling and extracting subsurface thermal fluids (steam or hot water) or injecting heat exchange media for use in power generation, district heating, and cooling.

[0003] In a typical geothermal heat exchange system, heat energy transfer occurs through two key steps: a heat medium (such as water, an organic working fluid, or a supercritical fluid) flows through an underground heat reservoir to absorb geothermal energy. The heat medium then transfers heat to the heat exchange medium through a heat exchanger, which then transports the heat to a generator or heating system. However, when the heat medium and the heat exchange medium exchange heat within the heat exchanger, the heat exchange medium near the heat medium may reach the desired temperature while the heat exchange medium farther from the heat medium has not yet reached the desired temperature. To achieve a relatively uniform temperature across the entire heat exchange medium, the heat exchange time must be extended, resulting in low geothermal energy extraction efficiency. Summary of the Invention

[0004] The main purpose of the present invention is to provide a low-temperature geothermal energy extraction device and method, aiming to improve the extraction efficiency of geothermal energy.

[0005] To achieve the above objectives, the present invention proposes a low-temperature geothermal energy extraction device comprising:

[0006] A heat exchange unit, wherein the heat exchange unit comprises a heat exchange tank and a plurality of heat exchange columns, wherein the plurality of heat exchange columns are arranged at intervals in the heat exchange tank, an upper partition, a lower partition, an adjustment shaft and a drive assembly are provided in the heat exchange column, the upper partition, the lower partition and the inner wall of the heat exchange column enclose a heat exchange chamber, the adjustment shaft is provided in the heat exchange chamber, a plurality of partition plates are provided at intervals along the circumferential side wall of the adjustment shaft, the plurality of partition plates divide the heat exchange chamber into a plurality of fan-shaped heat exchange areas, the drive assembly is provided on the side of the lower partition facing away from the upper partition, the drive assembly drives the adjustment shaft to rotate, a plurality of detection ports are provided on the side wall of the heat exchange column, each of the detection ports is connected to a fan-shaped heat exchange area, and a temperature difference power generation plate is provided in each detection port;

[0007] A heat extraction pipe group, comprising a water supply pipe and a water return pipe, wherein the water supply pipe is used to connect the geothermal water extraction well and the inner cavity of the heat exchange tank, and the water return pipe is used to connect the geothermal water return well and the inner cavity of the heat exchange tank;

[0008] a heat exchange tube group, the heat exchange tube group comprising a liquid supply pipe and a liquid return pipe, the liquid supply pipe being used to connect the liquid outlet cavity of the liquid storage tank and the plurality of the fan-shaped heat exchange areas, the liquid return pipe being used to connect the liquid return cavity of the liquid storage tank and the plurality of the fan-shaped heat exchange areas; and

[0009] The control unit, the driving assembly and the plurality of thermoelectric power generation sheets are all communicatively connected to the control unit.

[0010] In one embodiment, the upper partition is provided with a plurality of pressure relief holes, each of the pressure relief holes is communicated with one of the fan-shaped heat exchange areas, and a pressure sensor is provided in each of the pressure relief holes;

[0011] The heat exchange column further includes a plurality of pressure relief sleeves and a plurality of blocking components. Each of the pressure relief sleeves is provided corresponding to one of the pressure relief holes. Each of the blocking components is provided on one of the pressure relief sleeves and closes one of the pressure relief holes.

[0012] In one embodiment, the blocking assembly includes an elastic member and a blocking ball, the elastic member connects the blocking ball and the pressure relief sleeve, and the blocking ball closes the pressure relief hole.

[0013] In one embodiment, the liquid supply pipeline has a plurality of liquid supply branches, each of which is provided corresponding to a lower partition of the heat exchange column, and each of the liquid supply branches is provided with a plurality of liquid distribution pipes, each of which is connected to a fan-shaped heat exchange area;

[0014] The liquid return pipe has a plurality of liquid return branches, each of which is arranged corresponding to an upper partition of the heat exchange column. Each of the liquid return branches is provided with a plurality of liquid collecting pipes, and each of the liquid collecting pipes is communicated with a fan-shaped heat exchange area.

[0015] In one embodiment, solenoid valves are provided on both the liquid distributing pipe and the liquid collecting pipe, and the solenoid valves are communicatively connected to the control unit.

[0016] In one embodiment, the heat exchange unit further includes a mixing sleeve, which is rotatably disposed in the heat exchange tank, and the plurality of heat exchange columns are located in the mixing sleeve.

[0017] In one embodiment, a first circulation pump and a first throttle valve are provided on both the water supply pipe and the return pipe, and both the first circulation pump and the first throttle valve are communicatively connected to the control unit.

[0018] In one embodiment, a temperature sensor is provided at one end of the water supply pipe away from the heat exchange unit and at one end of the return pipe away from the heat exchange unit, and the temperature sensor is communicatively connected to the control unit.

[0019] In one embodiment, a second circulation pump and a second throttle valve are provided on both the liquid supply pipe and the liquid return pipe, and both the second circulation pump and the second throttle valve are communicatively connected to the control unit.

[0020] The present invention further provides a low-temperature geothermal energy extraction method, which is applied to the low-temperature geothermal energy extraction device described above. The low-temperature geothermal energy extraction method comprises:

[0021] Controlling the water supply pipe to supply heat medium to the heat exchange tank;

[0022] Controlling the liquid supply pipeline to supply heat exchange medium to the plurality of fan-shaped heat exchange areas;

[0023] detecting the power generation of each of the thermoelectric power generation sheets, and controlling the driving assembly to drive the adjusting shaft to rotate according to the power generation of each of the thermoelectric power generation sheets;

[0024] Controlling the liquid return pipe to extract the heat exchange medium from the plurality of fan-shaped heat exchange areas;

[0025] The return water pipe is controlled to extract the heat medium in the heat exchange tank.

[0026] In the technical solution of this invention, by measuring the power generated by the thermoelectric generator, the heat exchange conditions of the corresponding sector-shaped heat exchange zone can be determined. The thermoelectric generator operates based on the Seebeck effect, which states that when there is a temperature difference between the cold and hot ends of the thermoelectric generator, an electromotive force is generated. The greater the temperature difference, the greater the electromotive force and the greater the power generation. This allows the drive assembly to control the rotation of the adjustment shaft, causing the slower-heating sector-shaped heat exchange zone in a single heat exchange column to swap positions with the faster-heating sector-shaped heat exchange zone. This allows for more uniform heat absorption within each sector-shaped heat exchange zone, shortening the heat exchange time and significantly improving the efficiency of geothermal energy extraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0028] Figure 1 A schematic structural diagram of an embodiment of a low-temperature geothermal energy extraction device provided by the present invention;

[0029] Figure 2 A schematic structural diagram of an embodiment of a heat exchange tank provided by the present invention;

[0030] Figure 3 A top view of an embodiment of a heat exchange column provided by the present invention;

[0031] Figure 4 A cross-sectional view of an embodiment of a heat exchange column provided by the present invention;

[0032] Figure 5 for Figure 4 A partial enlarged view of point A in the middle.

[0033] Description of Figure Numbers:

[0034] 1. Liquid storage tank; 2. Second throttle valve; 3. Second circulation pump; 4. Return liquid pipeline; 5. Liquid supply pipeline; 6. Heat exchange unit; 7. First throttle valve; 8. First circulation pump; 9. Control unit; 10. Water supply pipeline; 11. Return water pipeline; 12. Temperature sensor; 13. Geothermal return water well; 14. Geothermal water production well; 15. Heat exchange column; 16. Thermoelectric generator; 17. Mixing sleeve; 18. Adjusting shaft; 19. Partition plate; 20. Solenoid valve; 21. Servo motor; 22. Liquid distribution pipe; 23. Pressure relief sleeve; 24. Spring; 25. Liquid collecting pipe; 26. Pressure relief hole; 27. Blocking ball; 28. Pressure sensor.

[0035] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making any creative efforts shall fall within the scope of protection of the present invention.

[0037] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0038] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0039] The present invention provides a low-temperature geothermal energy extraction device.

[0040] See also Figure 1 、 Figure 2 、 Figure 3 as well as Figure 4 In one embodiment of the present invention, the low-temperature geothermal energy extraction device includes a heat exchange unit 6, a heat extraction pipe group, a heat exchange pipe group, and a control unit 9; the heat exchange unit 6 includes a heat exchange tank and a plurality of heat exchange columns 15, the plurality of heat exchange columns 15 are arranged at intervals in the heat exchange tank, the heat exchange columns 15 are provided with an upper partition, a lower partition, an adjustment shaft 18 and a drive component, the upper partition, the lower partition and the inner wall of the heat exchange column 15 are surrounded to form a heat exchange chamber, the adjustment shaft 18 is arranged in the heat exchange chamber, and a plurality of partition plates 19 are arranged at intervals along the peripheral side wall of the adjustment shaft 18, the plurality of partition plates 19 divide the heat exchange chamber into a plurality of fan-shaped heat exchange areas, the drive component is arranged on the side of the lower partition facing away from the upper partition, and the drive component drives the adjustment The shaft 18 rotates, and a plurality of detection ports are opened on the side wall of the heat exchange column 15, each detection port is connected to a fan-shaped heat exchange area, and a thermoelectric power generation plate 16 is provided in each detection port; the heat extraction pipe group includes a water supply pipe 10 and a return water pipe 11, the water supply pipe 10 is used to connect the geothermal water production well 14 and the inner cavity of the heat exchange tank, and the return water pipe 11 is used to connect the geothermal return water well 13 and the inner cavity of the heat exchange tank; the heat exchange pipe group includes a liquid supply pipe 5 and a return liquid pipe 4, the liquid supply pipe 5 is used to connect the liquid outlet cavity of the liquid storage tank 1 and the plurality of fan-shaped heat exchange areas, and the return liquid pipe 4 is used to connect the return liquid cavity of the liquid storage tank 1 and the plurality of fan-shaped heat exchange areas; the drive assembly and the plurality of thermoelectric power generation plates 16 are all communicatively connected to the control unit 9.

[0041] A plurality of heat exchange columns 15 are arranged at intervals in the heat exchange tank. Such a layout can increase the heat exchange area and improve the heat exchange efficiency.

[0042] The heat exchange column 15 is equipped with an upper baffle, a lower baffle, an adjustment shaft 18, and a drive assembly. These upper and lower baffles, along with the inner wall of the column 15, form a heat exchange chamber for accommodating the heat exchange medium and performing heat exchange. The adjustment shaft 18 is located within the heat exchange chamber, and its surrounding walls are interspersed with multiple partitions 19, which divide the chamber into multiple sector-shaped heat exchange zones. The partitions 19 enable zonal management of the heat exchange medium, further streamlining the heat exchange process.

[0043] The drive assembly is installed on the side of the lower partition facing away from the upper partition, and is responsible for driving the adjustment shaft 18 to rotate. When the adjustment shaft 18 rotates, the partition plate 19 rotates accordingly, thereby changing the relative position and spatial distribution of each fan-shaped heat exchange zone. Specifically, the drive assembly includes a servo motor 21 and a groove wheel mechanism. The groove wheel mechanism connects the output end of the servo motor 21 and the adjustment shaft 18. The locking arc of the groove wheel corresponds one-to-one with the fan-shaped heat exchange zone. In this embodiment, four partition plates 19 are set, and four corresponding locking arcs are set. In this way, when the servo motor 21 drives the groove wheel mechanism for transmission, the groove wheel rotates 90° each time, corresponding to four independent fan-shaped heat exchange zones, that is, the groove wheel drives the adjustment shaft 18 to rotate 90° each time.

[0044] The sidewalls of the heat exchange column 15 are equipped with multiple inspection ports, each corresponding to a sector-shaped heat exchange zone. A thermoelectric generator 16 is installed within each port. The thermoelectric generator 16 operates based on the Seebeck effect, which generates an electromotive force when a temperature difference exists between its cold and hot ends. By measuring the power generated by the thermoelectric generator 16, temperature changes within each sector-shaped heat exchange zone can be monitored in real time, providing a basis for subsequent heat exchange optimization.

[0045] The water supply pipe 10 in the heat pipe group connects the geothermal water well 14 and the inner cavity of the heat exchange tank. Its function is to transport the high-temperature heat medium collected from the geothermal water well 14 to the heat exchange tank, providing a heat source for the heat exchange process.

[0046] The return pipe 11 is used to connect the geothermal return well 13 and the inner cavity of the heat exchange tank. After heat exchange, the low-temperature heat medium is transported back to the geothermal return well 13 through the return pipe 11 to achieve the recycling of geothermal resources.

[0047] The heat exchange medium (such as water, organic working fluid, etc.) in the liquid storage tank 1 is transported to each sector heat exchange area through the liquid supply pipe 5 to exchange heat with the high-temperature heat exchange medium transported by the heat pipe group.

[0048] The high-temperature heat exchange medium after heat exchange returns to the liquid storage tank 1 through the return liquid pipe 4, and can then be transported to a generator set or heating equipment, etc., for practical applications such as power generation and heating, thereby realizing the effective utilization of geothermal energy.

[0049] The control unit 9 is the intelligent control center of the entire device, communicating with the drive assembly and multiple thermoelectric generators 16. Its primary function is to collect real-time data on the power generation of each thermoelectric generator 16 and, based on pre-set algorithms and logic, determine the heat transfer status of each sector-shaped heat exchange zone. If it detects poor heat transfer performance in a sector-shaped heat exchange zone (e.g., the temperature does not meet preset requirements), the control unit 9 issues a command to control the operation of the drive assembly, thereby adjusting the rotation of the adjustment shaft 18 and changing the position and angle of the partition plate 19. This causes the slower-heating sector-shaped heat exchange zone within a single heat exchange column 15 to swap positions with the faster-heating sector-shaped heat exchange zone. This ensures that the heat transfer medium temperature in each sector-shaped heat exchange zone reaches the desired heating temperature more uniformly, improving the efficiency and stability of the entire heat exchange process.

[0050] In the technical solution of the present invention, by measuring the power generated by the thermoelectric generator 16, the heat exchange status of the corresponding sector-shaped heat exchange zone can be determined. The operating principle of the thermoelectric generator 16 is based on the Seebeck effect, that is, when there is a temperature difference between its cold and hot ends, an electromotive force is generated. The greater the temperature difference, the greater the electromotive force and the greater the power generation. In this way, the drive assembly can be controlled to drive the adjustment shaft 18 to rotate, causing the slower-heating sector-shaped heat exchange zone in a single heat exchange column 15 to swap positions with the faster-heating sector-shaped heat exchange zone. This ensures more uniform heat absorption within each sector-shaped heat exchange zone, shortens the heat exchange time, and significantly improves the efficiency of geothermal energy extraction.

[0051] Specifically, in one embodiment of the present invention, please refer to Figure 4 and Figure 5 The liquid supply pipe 5 has multiple liquid supply branches, each of which is arranged on the lower partition of a heat exchange column 15. Each liquid supply branch is provided with multiple liquid distribution pipes 22, and each liquid distribution pipe 22 is connected to a fan-shaped heat exchange area. The return liquid pipe 4 has multiple return liquid branches, each of which is arranged on the upper partition of a heat exchange column 15. Each return liquid branch is provided with multiple liquid collecting pipes 25, and each liquid collecting pipe 25 is connected to a fan-shaped heat exchange area. Through this hierarchical pipeline layout, the heat exchange medium can be evenly transported to each fan-shaped heat exchange area, ensuring that each area can obtain sufficient heat exchange medium, thereby improving heat exchange efficiency and uniformity. At the same time, the medium after heat exchange can be effectively collected from each fan-shaped heat exchange area and transported back to the liquid storage tank 1 or other subsequent equipment through the return liquid pipe 4, realizing the recycling of the medium, while ensuring the smooth operation and efficient heat transfer of the entire system. The liquid supply branch is connected to the liquid supply pipe 5 via a rotary joint, so that when the drive assembly drives the adjustment shaft 18 to rotate, the liquid supply branch can also rotate relative to the liquid supply pipe 5 while ensuring sealing.

[0052] Further, in one embodiment of the present invention, please refer to Figure 4 and Figure 5Solenoid valves 20 are installed on both the liquid distribution pipe 22 and the liquid collection pipe 25, and are in communication with the control unit 9. The provision of the solenoid valves 20 enables the control unit 9 to precisely control the inflow and outflow of the heat exchange medium according to the actual heat exchange requirements of each sector-shaped heat exchange zone. Simultaneously, by controlling the solenoid valves 20 on different liquid distribution pipes 22 and liquid collection pipes 25, each sector-shaped heat exchange zone can be flexibly and independently adjusted. This means that even within the same heat exchange column 15, different sector-shaped heat exchange zones can obtain different heat exchange medium supply and return strategies based on their own heat exchange progress and requirements.

[0053] Further, in one embodiment of the present invention, please refer to Figure 5 The upper partition is provided with a plurality of pressure relief holes 26, each of which is connected to a fan-shaped heat exchange area, and a pressure sensor 28 is provided in each pressure relief hole 26; the heat exchange column 15 also includes a plurality of pressure relief sleeves 23 and a plurality of plugging components, each of which is provided corresponding to a pressure relief hole 26, and each plugging component is provided on a pressure relief sleeve 23 and closes a pressure relief hole 26. The pressure relief sleeve 23 is connected to the liquid collecting pipe 25. After heat exchange, the temperature of the heat exchange medium in the fan-shaped heat exchange area increases, which increases the pressure in the space. When the heat exchange medium reaches the required temperature, the pressure in the fan-shaped heat exchange area can squeeze the plugging component out of the pressure relief hole 26. At this time, the heat exchange medium in the fan-shaped heat exchange area can flow into the liquid collecting pipe 25 through the pressure relief hole 26 and the pressure relief sleeve 23, and finally be transported back to the liquid storage tank 1.

[0054] Specifically, in one embodiment of the present invention, please refer to Figure 5 The blocking assembly includes an elastic member and a blocking ball 27. The elastic member connects the blocking ball 27 and the pressure relief sleeve 23, and the blocking ball 27 closes the pressure relief hole 26. In this embodiment, the elastic member is a spring 24. When the blocking ball 27 closes the pressure relief hole 26, it will squeeze the pressure sensor 28. The temperature of the heat exchange medium in the fan-shaped heat exchange area will increase after heat exchange, which will increase the pressure in the space where it is located, so that the blocking ball 27 will be released from squeezing the pressure sensor 28, and the pressure relief hole 26 will no longer be closed. At this time, the control unit 9 detects the pressure change of the pressure sensor 28, opens the corresponding solenoid valve 20 on the liquid distribution pipe 22 and the liquid collection pipe 25, and then transports the heat exchange medium back to the liquid storage tank 1 for energy utilization. In this way, it can be ensured that the heat exchange medium transported back to the liquid storage tank 1 reaches the required temperature.

[0055] In order to improve the heat exchange efficiency, in one embodiment of the present invention, please refer to Figure 2 The heat exchange unit 6 further includes a mixing sleeve 17, which is rotatably disposed within the heat exchange tank. The plurality of heat exchange columns 15 are located within the mixing sleeve 17. The rotation of the mixing sleeve 17 promotes the flow of the heat medium within the heat exchange tank, allowing the heat medium to more evenly contact the heat exchange columns 15, thereby improving heat exchange efficiency.

[0056] Further, in one embodiment of the present invention, please refer to Figure 1 The water supply pipeline 10 and the return pipeline 11 are both equipped with a first circulation pump 8 and a first throttle valve 7, both of which are communicatively connected to a control unit 9. The first circulation pump 8 is installed on both the water supply pipeline 10 and the return pipeline 11. Its primary function is to provide power support for the circulation of the heat medium within the pipeline. The operation of the first circulation pump 8 ensures that the heat medium circulates at a stable flow rate and flow rate between the geothermal water well 14, the heat exchange tank, and the geothermal return well 13, thereby efficiently carrying underground heat energy to the heat exchange tank and, after heat exchange, transporting the cooled heat medium back to the geothermal return well 13. Similarly, the water supply pipeline 10 and the return pipeline 11 are also equipped with a first throttle valve 7. The primary function of the first throttle valve 7 is to finely regulate the flow rate of the heat medium within the pipeline. By varying the throttle valve opening, the flow rate of the heat medium can be precisely controlled, thereby affecting the heat transfer rate during the heat exchange process.

[0057] Specifically, in one embodiment of the present invention, please refer to Figure 1 Temperature sensors 12 are provided at both the end of the water supply pipe 10 away from the heat exchange unit 6 and the end of the return pipe 11 away from the heat exchange unit 6. The temperature sensors 12 are in communication with the control unit 9. The temperature sensors 12 can detect the temperature of the heat medium entering and leaving the heat exchange unit 6. Real-time feedback of this temperature data enables the control unit 9 to dynamically adjust the operating parameters of various aspects of the heat exchange system, such as the flow rate, flow velocity, heat exchange time, and heat exchange path of the heat exchange medium, based on the actual temperature of the geothermal resource, to ensure that the heat medium can provide sufficient thermal energy within the heat exchange unit 6.

[0058] Further, in one embodiment of the present invention, please refer to Figure 1 A second circulation pump 3 and a second throttle valve 2 are both installed on the liquid supply pipe 5 and the liquid return pipe 4. Both the second circulation pump 3 and the second throttle valve 2 are communicatively connected to the control unit 9. The second circulation pump 3 is installed on both the liquid supply pipe 5 and the liquid return pipe 4. Its primary function is to provide power support for the circulation of the heat exchange medium within the heat exchange tube assembly, ensuring stable and efficient flow of the heat exchange medium between the liquid storage tank 1 and each sector-shaped heat exchange zone. Through the operation of the second circulation pump 3, the heat exchange medium can promptly transfer heat from the heat exchange unit 6 to energy-consuming terminals such as generators or heating equipment, while simultaneously returning the low-temperature medium to the heat exchange unit 6 for reheating, forming an efficient heat recycling process. A second throttle valve 2 is also installed on the liquid supply pipe 5 and the liquid return pipe 4. Its core function is to finely control the flow rate of the heat exchange medium. By varying the opening of the second throttle valve 2, the flow rate of the heat exchange medium into each sector-shaped heat exchange zone and the return flow rate from each sector-shaped heat exchange zone can be precisely controlled, thereby achieving precise management of the heat exchange process.

[0059] The present invention also provides a low-temperature geothermal energy extraction method, which is applied to the above-mentioned low-temperature geothermal energy extraction device. The low-temperature geothermal energy extraction method includes:

[0060] Step S1: Control the water supply pipe 10 to supply heat medium to the heat exchange tank;

[0061] Control unit 9 sends commands to activate first circulation pump 8, installed on water supply pipe 10, to provide power for transporting the heat medium from geothermal water well 14 to the heat exchange tank. Simultaneously, the opening of first throttle valve 7 on water supply pipe 10 is adjusted based on the heat medium temperature at the end of water supply pipe 10 away from heat exchange unit 6, as detected by temperature sensor 12, and other parameters such as the pressure within the heat exchange tank.

[0062] Step S2: Control the liquid supply pipe 5 to supply heat exchange medium to the multiple sector-shaped heat exchange areas;

[0063] Control unit 9 activates second circulation pump 3 on liquid supply pipeline 5, pushing heat exchange medium (e.g., water, organic fluid, etc.) from liquid storage tank 1 to each sector-shaped heat exchange zone. Based on a pre-set heat exchange strategy and the real-time heat exchange performance of each sector-shaped heat exchange zone (e.g., estimated heat exchange performance based on power generation monitored by thermoelectric generator 16), control unit 9 adjusts the opening of second throttle valve 2 corresponding to each liquid distribution pipe 22 on liquid supply pipeline 5.

[0064] Step S3: detecting the power generation of each thermoelectric power generation sheet 16 , and controlling the driving assembly to drive the adjustment shaft 18 to rotate according to the power generation of each thermoelectric power generation sheet 16 ;

[0065] The thermoelectric generator 16 within the detection port corresponding to each sector heat exchange zone generates electricity due to the temperature difference between the cold and hot ends. This power generation reflects the heat exchange status within the corresponding sector heat exchange zone in real time, and the power generation signal is continuously transmitted to the control unit 9. An algorithm built into the control unit 9 analyzes and processes the power generation data from each thermoelectric generator 16. Based on a pre-established relationship model between power generation and heat exchange performance, the control unit 9 determines whether heat exchange within each sector heat exchange zone is sufficient. For example, areas where power generation falls below a set threshold may indicate insufficient heat exchange, meaning the heat exchange medium has not reached the required temperature; areas where power generation is stable and high indicate good heat exchange performance. Based on this analysis, the control unit 9 sends a control signal to the drive assembly, rotating the adjustment shaft 18. The rotation of the adjustment shaft 18 causes the surrounding partition plates 19 to change position and angle, causing the slower-heating sector heat exchange zones within a single heat exchange column 15 to swap positions with the faster-heating sector heat exchange zones.

[0066] Step S4: controlling the liquid return pipe 4 to extract the heat exchange medium from the plurality of sector-shaped heat exchange areas;

[0067] Control unit 9 activates second circulation pump 3 on liquid return pipe 4 to pump heat exchange medium from the sector-shaped heat exchange zones and return it to liquid storage tank 1. Control unit 9 also adjusts the opening of second throttle valve 2 corresponding to each liquid header 25 on liquid return pipe 4 based on the heat exchange conditions in each sector-shaped heat exchange zone and the temperature and flow requirements of the heat exchange medium for subsequent energy-consuming equipment.

[0068] Step S5: Control the return water pipe 11 to extract the heat medium in the heat exchange tank.

[0069] Control unit 9 activates first circulation pump 8 on return pipe 11, pumping the heat medium (the medium that has released heat to the heat exchange medium and whose temperature has dropped) from the heat exchange tank and transporting it back to geothermal return well 13. Control unit 9 also adjusts the opening of first throttle valve 7 on return pipe 11 based on factors such as pressure changes within the heat exchange tank, return water temperature, and the capacity of geothermal return well 13.

[0070] In this embodiment, precise control of the heat medium circulation in the water supply pipe 10 and the return water pipe 11, as well as the heat exchange medium circulation in the liquid supply pipe 5 and the return liquid pipe 4, ensures that heat is efficiently transferred from the underground heat reservoir to the surface and fully utilized for applications such as power generation and heating. Simultaneously, by real-time monitoring of the power generation of the thermoelectric generator 16 and adjusting the distribution of the heat exchange medium in conjunction with the control drive assembly, the slower-heating sector-shaped heat exchange areas in a single heat exchange column 15 can be swapped with the faster-heating sector-shaped heat exchange areas. This allows for more uniform heat absorption within each sector-shaped heat exchange area, shortening the heat exchange time and significantly improving the efficiency of geothermal energy extraction.

[0071] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by utilizing the contents of the present invention's description and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A low-temperature geothermal energy extraction device, characterized in that: include: A heat exchange unit, wherein the heat exchange unit comprises a heat exchange tank and a plurality of heat exchange columns, wherein the plurality of heat exchange columns are arranged at intervals in the heat exchange tank, an upper partition, a lower partition, an adjustment shaft and a drive assembly are provided in the heat exchange column, the upper partition, the lower partition and the inner wall of the heat exchange column enclose a heat exchange chamber, the adjustment shaft is provided in the heat exchange chamber, a plurality of partition plates are provided at intervals along the circumferential side wall of the adjustment shaft, the plurality of partition plates divide the heat exchange chamber into a plurality of fan-shaped heat exchange areas, the drive assembly is provided on the side of the lower partition facing away from the upper partition, the drive assembly drives the adjustment shaft to rotate, a plurality of detection ports are provided on the side wall of the heat exchange column, each of the detection ports is connected to a fan-shaped heat exchange area, and a temperature difference power generation plate is provided in each detection port; A heat extraction pipe group, comprising a water supply pipe and a water return pipe, wherein the water supply pipe is used to connect the geothermal water extraction well and the inner cavity of the heat exchange tank, and the water return pipe is used to connect the geothermal water return well and the inner cavity of the heat exchange tank; a heat exchange tube group, the heat exchange tube group comprising a liquid supply pipe and a liquid return pipe, the liquid supply pipe being used to connect the liquid outlet cavity of the liquid storage tank and the plurality of the fan-shaped heat exchange areas, the liquid return pipe being used to connect the liquid return cavity of the liquid storage tank and the plurality of the fan-shaped heat exchange areas; as well as A control unit, the drive assembly and the plurality of thermoelectric power generation sheets are all communicatively connected to the control unit; The upper partition is provided with a plurality of pressure relief holes, each of which is connected to one of the fan-shaped heat exchange areas, and each of which is provided with a pressure sensor; The heat exchange column further includes a plurality of pressure relief sleeves and a plurality of plugging components, each of the pressure relief sleeves is provided corresponding to one of the pressure relief holes, and each of the plugging components is provided on one of the pressure relief sleeves and closes one of the pressure relief holes; The blocking assembly includes an elastic member and a blocking ball, the elastic member connects the blocking ball and the pressure relief sleeve, and the blocking ball closes the pressure relief hole; The liquid supply pipeline has a plurality of liquid supply branches, each of which is provided corresponding to the lower partition of the heat exchange column, and each of which is provided with a plurality of liquid distribution pipes, each of which is connected to a fan-shaped heat exchange area; The liquid return pipe has a plurality of liquid return branches, each of which is arranged corresponding to an upper partition of the heat exchange column. Each of the liquid return branches is provided with a plurality of liquid collecting pipes, and each of the liquid collecting pipes is communicated with a fan-shaped heat exchange area.

2. The low-temperature geothermal energy extraction device according to claim 1, characterized in that: The liquid distributing pipe and the liquid collecting pipe are both provided with electromagnetic valves, and the electromagnetic valves are communicatively connected with the control unit.

3. The low-temperature geothermal energy extraction device according to claim 1, characterized in that: The heat exchange unit further includes a mixing sleeve, which is rotatably disposed in the heat exchange tank, and the plurality of heat exchange columns are located in the mixing sleeve.

4. The low-temperature geothermal energy extraction device according to claim 1, characterized in that: A first circulation pump and a first throttle valve are both provided on the water supply pipe and the return water pipe. The first circulation pump and the first throttle valve are both communicatively connected to the control unit.

5. The low-temperature geothermal energy extraction device according to claim 1, characterized in that: One end of the water supply pipe away from the heat exchange unit and one end of the return pipe away from the heat exchange unit are both provided with temperature sensors, and the temperature sensors are communicatively connected with the control unit.

6. The low-temperature geothermal energy extraction device according to claim 1, characterized in that: A second circulation pump and a second throttle valve are both provided on the liquid supply pipeline and the liquid return pipeline, and the second circulation pump and the second throttle valve are both communicatively connected to the control unit.

7. A low-temperature geothermal energy extraction method, applied to the low-temperature geothermal energy extraction device according to claim 1, characterized in that: The low-temperature geothermal energy extraction method comprises: Controlling the water supply pipe to supply heat medium to the heat exchange tank; Controlling the liquid supply pipeline to supply heat exchange medium to the plurality of fan-shaped heat exchange areas; detecting the power generation of each of the thermoelectric power generation sheets, and controlling the driving assembly to drive the adjusting shaft to rotate according to the power generation of each of the thermoelectric power generation sheets; Controlling the liquid return pipe to extract the heat exchange medium from the plurality of fan-shaped heat exchange areas; The return water pipe is controlled to extract the heat medium in the heat exchange tank.

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