Cross-scale geothermal reservoir fracture network quantitative characterization and thermal extraction efficiency evaluation device

Abstract

The invention discloses a cross-scale geothermal reservoir fracture network quantitative characterization and thermal extraction efficiency evaluation device, and relates to the technical field of geothermal energy, the cross-scale geothermal reservoir fracture network quantitative characterization and thermal extraction efficiency evaluation device comprises a double-layer underframe, the top end of the double-layer underframe is provided with a fracture network rock sample maintenance mechanism, and the fracture network rock sample maintenance mechanism comprises a prefabricated maintenance cylinder; the fracture network rock sample maintenance device is scientific and reasonable in structure and safe and convenient to use, a fracture network rock sample maintenance mechanism is arranged, through cooperation of a rotary knob gear, an adjusting push rod and a clamping arc plate, the fracture network rock sample maintenance device can maintain the fracture network rock sample, and the fracture network rock sample maintenance device can maintain the fracture network rock sample. According to the clamping device for the salt slice crack grid structure, the salt slice crack grid structures of different specifications can be conveniently clamped, so that the salt slice crack grid structures are fixed in the clamping cylinder, during follow-up injection of concrete for covering, the stability of the salt slice crack grid structures is guaranteed, deviation is prevented, manufacturing accuracy is improved, and a sealing sliding cover is pushed to descend through an electric hydraulic push rod.

Description

Technical Field

[0001] This invention relates to the field of geothermal energy technology, specifically to a device for quantitative characterization of fracture networks in geothermal reservoirs across scales and for evaluating thermal extraction efficiency. Background Technology

[0002] Geothermal resources are a clean and renewable energy source with large reserves, wide distribution, and good stability. The development and utilization of geothermal resources are of great significance for energy conservation and emission reduction. Geothermal heating is an important way to develop and utilize geothermal resources. It has the advantages of being clean, pollution-free, having low operating costs, and high returns from comprehensive resource utilization. For example, a geothermal heat conduction simulation device and experimental method were previously disclosed, with application number CN202211202000.0. This patent can realistically reflect the changes in geothermal reservoirs under different development environments, and finally guide the rational and sustainable development and utilization of geothermal resources. However, in actual simulations, it is inconvenient to prepare rock samples that conform to the fracture grid structure of the original core samples from different regions. This causes deviations in the simulated data, affecting the accuracy of subsequent assessments. Therefore, to avoid the aforementioned technical problems, it is indeed necessary to provide a cross-scale geothermal reservoir fracture network quantitative characterization and thermal extraction efficiency evaluation device to overcome the deficiencies in the existing technology. Summary of the Invention

[0003] This invention provides a device for quantitative characterization of fracture networks in geothermal reservoirs across scales and for evaluating the efficiency of thermal extraction. It can effectively solve the problem mentioned in the background art that it is inconvenient to prepare rock samples that conform to the fracture network structure of the original cores from different regions, which leads to deviations in the simulated measurement data and affects the accuracy of subsequent evaluations.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a device for quantitative characterization of fracture networks and evaluation of thermal extraction efficiency in geothermal reservoirs across scales, comprising a double-layer base frame, wherein a fracture network rock sample curing mechanism is provided at the top of the double-layer base frame, and the fracture network rock sample curing mechanism comprises a prefabricated curing cylinder; The top of the double-layer base frame is snapped with a prefabricated curing cylinder, and the inside of the prefabricated curing cylinder is movably connected to a detachable inner cylinder. The outside of the detachable inner cylinder is threadedly connected to a demolding base. The outer side of the detachable inner cylinder is fitted with a positioning ring by a threaded sleeve. A cross support is clamped to the inner wall of the positioning ring. An electric hydraulic push rod is clamped at equal intervals at the bottom end of the cross support. A sealing slide cover is clamped to the bottom end of the electric hydraulic push rod. A clamping cylinder is engaged in the middle of the sealing sliding cover. Both ends of the clamping cylinder are connected to adjusting push rods at equal intervals via threads. One end of each adjusting push rod is engaged with a clamping arc plate, and the other end of each adjusting push rod is engaged with a knob gear.

[0005] According to the above technical solution, a gap is left between the detachable inner cylinder and the precast curing cylinder, and the outer side of the demolding base is in contact with the inner wall of the precast curing cylinder.

[0006] According to the above technical solution, the top of the sealing slide cover is provided with a filling port, the two adjusting push rods on the same side have opposite rotation directions of their outer threads, and the two knob gears on the same side mesh with each other.

[0007] According to the above technical solution, a telescopic slide tube is snapped onto the top of the clamping cylinder, an anti-deviation sleeve is sleeved on the outside of the telescopic slide tube, a water delivery hose is threaded onto the top of the anti-deviation sleeve, and a water pump is installed on the outside of the water delivery hose. The double-layer base frame is equipped with a deionized water tank, and a recycling circulation pipe is connected between the deionized water tank and the prefabricated curing cylinder.

[0008] According to the above technical solution, the top of the anti-deviation sleeve penetrates the top of the cross support frame, and the water pump and the electric hydraulic push rod are both powered by an external power source.

[0009] According to the above technical solution, one end of the water delivery hose is connected to one end of the deionized water tank, and a valve is installed inside the recycling pipe.

[0010] According to the above technical solution, a thermal extraction simulation and waste heat utilization mechanism is provided at the top of the double-layer base frame, and the thermal extraction simulation and waste heat utilization mechanism includes a high-temperature and high-pressure reaction vessel. A high-temperature and high-pressure reactor is installed at the top of the double-layer base frame. An annular support is connected inside the high-temperature and high-pressure reactor. Internally threaded cylinders are equidistantly engaged inside the annular support, and a positioning top rod is connected inside the internally threaded cylinders by threads. The annular support has annular cavities at equal intervals inside, and an electric heating plate is installed at equal intervals inside one annular cavity. The double-layer base frame is equipped with a circulating water tank. A water supply pipe is connected to one end of the circulating water tank, and a temperature measuring water injection pipe is connected to the top of the circulating water tank. A water supply pump is installed on the outside of both the water supply pipe and the temperature measuring water injection pipe. Water temperature sensors are installed on the inner wall of the temperature-measuring water injection pipe and the inner wall of the annular bracket. One end of the high-temperature and high-pressure reactor is connected to a heat-insulating water pipe, and the bottom end of the heat-insulating water pipe is connected to a flow direction regulating valve cylinder. A connecting pipe is also connected between the prefabricated curing cylinder and the flow direction regulating valve. One end of the double-layer base frame is fitted with heat dissipation fins, the top of the heat dissipation fins is fitted with a T-shaped pipe, and drain pipes are symmetrically fitted to the outside of the T-shaped pipes. The bottom end of the heat dissipation fins is fitted with an inlet pipe.

[0011] According to the above technical solution, one end of the positioning rod is rotatably connected to a rubber pad, the other end of the water supply pipe is connected to the outside of the high-temperature and high-pressure reactor, and the top end of the temperature measuring water injection pipe is connected to the bottom end of the high-temperature and high-pressure reactor.

[0012] According to the above technical solution, the water temperature detection sensors are equidistantly distributed at the top of the inner wall of the annular bracket, and both the water supply pump and the water temperature detection sensors are powered by an internal power source.

[0013] According to the above technical solution, one end of the return pipe is connected to the outside of the flow direction regulating valve cylinder, and the other end of the return pipe is connected to the outside of the prefabricated curing cylinder.

[0014] Compared with the prior art, the beneficial effects of the present invention are: the present invention has a scientific and reasonable structure and is safe and convenient to use. 1. A fractured network rock sample curing mechanism was set up. Through the cooperation of knob gears, adjusting push rods and clamping arc plates, it is convenient to clamp salt sheet fractured mesh structures of different specifications, thereby fixing them inside the clamping cylinder. When concrete is injected for covering, the stability of the salt sheet fractured mesh structure is ensured, preventing displacement and providing precision in production. The sealing slide cover is pushed down by an electric hydraulic push rod, controlling the internal space at the bottom of the sealing slide cover, which makes it easy to produce rock samples that meet the height requirements and increases adaptability. By combining a water pump, an ion water tank, an anti-deviation sleeve, and a telescopic slide pipe, deionized water can be easily delivered into the clamping cylinder to melt the salt fracturing grid structure, forcing the solidified concrete to form the required fracturing grid, thus completing the preparation of the rock sample and improving efficiency. Opening the valve inside the recycling pipe sends the deionized water back to the ion water tank for easy recycling and reduced waste.

[0015] 2. A thermal extraction testing and waste heat utilization mechanism was set up. Through the cooperation of the internal threaded cylinder and the positioning top rod, the rock sample with the sensor installed was positioned inside the annular support. The electric heating plate was used in conjunction with the high temperature and high pressure reactor to increase the temperature and pressure of the rock sample, simulating the geothermal environment. Then, using the cooperation of the water supply pump and the temperature measuring water injection pipe, water from the circulating water tank was injected from the bottom of the rock sample and flowed upward along the internal fissure grid of the rock sample. At the same time, the initial temperature of the injected water and the temperature of the water flowing out through the fissure grid were measured by the water temperature detection sensor. The data was simulated and calculated by the computer to evaluate the thermal extraction efficiency, realizing the efficiency of geothermal thermal extraction and improving convenience. At the same time, the rock sample can be repeatedly prepared, and multiple sets of data can be tested and compared to improve accuracy. The high-temperature and high-pressure reactor is preheated by an electric heating plate to facilitate the subsequent simulation of the geothermal environment. At the same time, the water inside the circulating water tank is pumped into an annular cavity through the cooperation of water pipes and water supply pumps. This allows the electric heating plate to heat the water entering the annular cavity. The heated water is then sent into the gap between the precast curing cylinder and the detachable inner cylinder through insulated water pipes, flow regulating valves and connecting pipes. This increases the temperature of the precast curing cylinder, cures the concrete, improves the curing effect, and increases the utilization rate of resources. After heat exchange, the water is sent into the heat dissipation fins through the drain pipe and T-junction. After cooling, it is sent back to the circulating water tank for easy circulation and continuous maintenance. When maintenance is not required, the flow direction is adjusted by the flow regulating valve, and then the water is sent back into the heat dissipation fins through another drain pipe and T-junction. After heat dissipation, the water is recycled. The water inside the annular cavity flows back into the circulating water tank through the water supply pipe, reducing resource waste.

[0016] In summary, by combining the fractured network rock sample preservation mechanism with the thermal extraction testing and waste heat utilization mechanism, suitable fractured grid rock samples can be produced according to requirements. This facilitates water flow through the fractured grid during thermal extraction testing, simulating a geothermal environment, improving the accuracy of measurement data, and providing sufficient data for subsequent thermal extraction evaluation. Furthermore, the heat can be utilized to preserve the rock samples during the geothermal environment simulation, improving the preservation effect and increasing the quality of rock sample preparation. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0018] In the attached diagram: Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the fracture network rock sample preservation mechanism of the present invention; Figure 3 This is a schematic diagram of the installation structure of the telescopic slide tube of the present invention; Figure 4 This is a schematic diagram of the installation structure of the adjusting push rod of the present invention; Figure 5 This is a schematic diagram of the thermal extraction testing and waste heat utilization mechanism of the present invention; Figure 6 This is a schematic diagram of the installation structure of the temperature measuring water injection pipe of the present invention; Figure 7 This is a schematic diagram of the installation structure of the positioning top rod of the present invention.

[0019] Numbered in the diagram: 1. Double-layer base frame; 2. Fractured network rock sample curing mechanism; 201. Prefabricated curing cylinder; 202. Demountable inner cylinder; 203. Demolding base; 204. Positioning ring; 205. Cross support; 206. Electro-hydraulic push rod; 207. Sealing sliding cover; 208. Clamping cylinder; 209. Adjusting push rod; 210. Clamping arc plate; 211. Knob gear; 212. Telescopic slide tube; 213. Anti-deviation sleeve; 214. Water delivery hose; 215. Water pump; 216. Deionized water tank; 217. Recycling circulation pipe; 3. Thermal extraction simulation and waste heat utilization mechanism; 301. High temperature and high pressure reactor; 302. Annular support; 303. Internally threaded cylinder; 304. Positioning top rod; 305. Water temperature detection sensor; 306. Annular cavity; 307. Electric heating plate; 308. Circulating water tank; 309. Water supply pipe; 310. Temperature measuring water injection pipe; 311. Water supply pump; 312. Insulated water pipe; 313. Flow direction regulating valve; 314. Connecting pipe; 315. Heat dissipation fins; 316. T-shaped pipe; 317. Drain pipe; 318. Inlet pipe. Detailed Implementation

[0020] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0021] Example: Figure 1-7 As shown, the present invention provides a technical solution, a device for quantitative characterization of fracture network and thermal extraction efficiency evaluation of cross-scale geothermal reservoir, including a double-layer base frame 1, a fracture network rock sample curing mechanism 2 is provided at the top of the double-layer base frame 1, and the fracture network rock sample curing mechanism 2 includes a prefabricated curing cylinder 201. The top of the double-layer base frame 1 is snapped with a precast curing cylinder 201. The precast curing cylinder 201 is movably connected to a detachable inner cylinder 202. The outer side of the detachable inner cylinder 202 is threadedly connected to a demolding base 203. In order to facilitate disassembly and assembly, a gap is left between the detachable inner cylinder 202 and the precast curing cylinder 201. The outer side of the demolding base 203 is in contact with the inner wall of the precast curing cylinder 201. The outer side of the detachable inner cylinder 202 is threadedly connected to a positioning ring 204. A cross support 205 is snapped into the inner wall of the positioning ring 204. An electric hydraulic push rod 206 is equidistantly snapped into the bottom end of the cross support 205. A sealing slide cover 207 is snapped into the bottom end of the electric hydraulic push rod 206. A clamping cylinder 208 is snapped into the middle of the sealing slide cover 207. Both ends of the clamping cylinder 208 are connected to adjusting push rods 209 by threads at equal intervals. One end of the two adjusting push rods 209 is snapped into a clamping arc plate 210, and the other end of the two adjusting push rods 209 is snapped into a knob gear 211. In order to ensure the pushing effect, a material inlet is opened at the top of the sealing slide cover 207. The threads on the outer sides of the two adjusting push rods 209 on the same side rotate in opposite directions, and the two knob gears 211 on the same side mesh with each other. The top of the clamping cylinder 208 is snapped with a telescopic slide tube 212, and an anti-deviation sleeve 213 is sleeved on the outside of the telescopic slide tube 212. The top of the anti-deviation sleeve 213 is connected to a water delivery hose 214 by a thread, and a water pump 215 is installed on the outside of the water delivery hose 214. In order to ensure the lifting effect of the sealing slide cover 207, the top of the anti-deviation sleeve 213 passes through the top of the cross support 205. The water pump 215 and the electric hydraulic push rod 206 are both powered by an external power source. The double-layer base frame 1 is equipped with a deionized water tank 216. A recycling pipe 217 is connected between the deionized water tank 216 and the prefabricated curing cylinder 201. In order to facilitate water supply, one end of the water supply hose 214 is connected to one end of the deionized water tank 216. A valve is installed inside the recycling pipe 217. The top of the double-layer base frame 1 is equipped with a heat extraction simulation and waste heat utilization mechanism 3, which includes a high-temperature and high-pressure reactor 301. A high-temperature and high-pressure reactor 301 is installed at the top of the double-layer base frame 1. An annular support 302 is connected inside the high-temperature and high-pressure reactor 301. An internally threaded cylinder 303 is equidistantly engaged inside the annular support 302, and a positioning push rod 304 is threadedly connected inside the internally threaded cylinder 303. The annular bracket 302 has annular cavities 306 equidistantly spaced inside, and an electric heating plate 307 is installed equidistantly inside one annular cavity 306. The double-layer base frame 1 is equipped with a circulating water tank 308. One end of the circulating water tank 308 is connected to a water supply pipe 309, and the top of the circulating water tank 308 is connected to a temperature measuring water injection pipe 310. Water supply pumps 311 are installed on the outside of both the water supply pipe 309 and the temperature measuring water injection pipe 310. In order to position the rock sample, a rubber pad is rotatably connected to one end of the positioning rod 304. The other end of the water supply pipe 309 is connected to the outside of the high temperature and high pressure reactor 301, and the top of the temperature measuring water injection pipe 310 is connected to the bottom of the high temperature and high pressure reactor 301. Water temperature sensors 305 are installed on the inner wall of the temperature-measuring water injection pipe 310 and the inner wall of the annular bracket 302. In order to detect the water temperature in real time, the water temperature sensors 305 are equidistantly distributed at the top of the inner wall of the annular bracket 302. The water supply pump 311 and the water temperature sensors 305 are both powered by an internal power supply. One end of the high-temperature and high-pressure reactor 301 is connected to a heat-insulating water pipe 312, and the bottom end of the heat-insulating water pipe 312 is connected to a flow direction regulating valve cylinder 313. Furthermore, a connecting pipe 314 is connected between the prefabricated curing cylinder 201 and the flow direction regulating valve 313. One end of the double-layer base frame 1 is fitted with a heat dissipation fin 315, the top of the heat dissipation fin 315 is fitted with a three-way pipe 316, and the outside of the three-way pipe 316 is symmetrically fitted with a drain pipe 317. The bottom end of the heat dissipation fin 315 is fitted with an inlet pipe 318. In order to facilitate circulation, one end of the drain pipe 317 is connected to the outside of the flow direction regulating valve cylinder 313, and the other end of the drain pipe 317 is connected to the outside of the prefabricated curing cylinder 201. The working principle and usage process of this invention are as follows: First, the fracture grid structure of the original core of the tested area is obtained by three-dimensional CT scanning. Then, the salt sheet is made to be the same as the fracture grid structure of the original core according to the requirements and recorded. Then, the detachable inner cylinder 202 is taken out to facilitate the placement of one end of the prepared salt sheet fracture grid structure into the clamping cylinder 208. At the same time, the knob gear 211 is rotated to drive the adjusting push rod 209 to rotate. The effect of the knob gear 211 transmission is used to make the two adjusting push rods 209 on the same side rotate together, pushing the clamping arc plate 210 to move and clamping and fixing one end of the salt sheet fracture grid structure. Then, the detachable inner cylinder 202 is placed inside the precast curing cylinder 201, and according to the height of the rock sample, the electric hydraulic push rod 206 is activated to push the sealing slide cover 207 down, controlling the internal space of the sealing slide cover 207 to facilitate the production of rock samples that meet the height requirements. Then, the mixed concrete is injected into the precast curing cylinder 201 through the injection port, filling the bottom of the sealing slide cover 207, and left to cure, allowing the concrete to solidify and simultaneously wrapping the salt sheet cracked mesh structure. Next, the water pump 215 is started to extract the deionized water from the deionized water tank 216 and send it into the anti-deviation sleeve 213. The water then flows into the clamping cylinder 208 along the telescopic slide pipe 212 to melt the salt fractal grid structure and form the required fractal grid, thus completing the preparation of the rock sample. After preparation, the valve inside the recycling pipe 217 is opened to send the deionized water back to the deionized water tank 216 for easy recycling and to reduce waste. Next, the rock sample can be easily extracted from the precast curing cylinder 201 by using the detachable inner cylinder 202, and then the demolding base 203 can be rotated to release the limit, making it easy to remove the rock sample from the bottom of the detachable inner cylinder 202. Then, a pressure sensor is installed on the rock sample and placed inside the annular support 302. At the same time, the positioning top rod 304 is rotated and moved along the inside of the internal threaded cylinder 303 to support and fix the rock sample to prevent displacement. The rock sample is then heated and pressurized by the electric heating plate 307 to simulate the geothermal environment. Subsequently, the water in the circulating water tank 308 is injected into the high-temperature and high-pressure reactor 301 by the water supply pump 311 on the temperature measuring water injection pipe 310. The water flows from the bottom of the rock sample upward along the fracture grid. The temperature of the injected water and the water flowing out through the fracture grid are measured by the water temperature detection sensor 305 and the data is recorded. The thermal extraction efficiency is evaluated by computer simulation technology. After the test is completed, the water is returned to the circulating water tank 308 through the temperature measuring water injection pipe 310. In addition, during the prefabrication of rock samples, the water supply pump 311 on the water supply pipe 309 can be activated to pump the water inside the circulating water tank 308 into another annular cavity 306. Simultaneously, the electric heating plate 307 is activated to heat the water entering the annular cavity 306. Then, through the cooperation of the heat-insulating water pipe 312, the flow direction regulating valve 313 and the connecting pipe 314, the heated water is sent into the gap between the prefabricated curing cylinder 201 and the detachable inner cylinder 202, thereby increasing the temperature of the prefabricated curing cylinder 201 and the curing temperature, ensuring the curing effect. The electric heating plate 307 can also preheat the high-temperature and high-pressure reactor 301, providing convenience for subsequent simulation of the geothermal environment and improving the utilization rate of resources. Finally, the heat-exchanged water is sent into the heat dissipation fins 315 through the return pipe 317 and the three-way pipe 316. After cooling, it is sent back to the circulating water tank 308 through the inlet pipe 318 for easy circulation and continuous maintenance. When maintenance is not required, the flow direction is adjusted by the flow direction regulating valve 313, so that the water enters the flow direction regulating valve 313 and is discharged from another return pipe 317, entering the three-way pipe 316 and the heat dissipation fins 315 for heat dissipation and recycling. The water in the annular cavity 306 is returned to the circulating water tank 308 through the water supply pipe 309, reducing resource waste.

[0022] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for quantitative characterization of fracture networks and evaluation of thermal extraction efficiency in geothermal reservoirs across scales, comprising a double-layer base (1), characterized in that: The top of the double-layer base frame (1) is provided with a fracture network rock sample curing mechanism (2), which includes a prefabricated curing cylinder (201). The top of the double-layer base frame (1) is snapped with a prefabricated curing cylinder (201), and the prefabricated curing cylinder (201) is movably connected to a detachable inner cylinder (202). The outer side of the detachable inner cylinder (202) is threaded with a demolding base (203). The detachable inner cylinder (202) is threaded with a positioning ring (204) on the outside. A cross support (205) is snapped into the inner wall of the positioning ring (204). An electric hydraulic push rod (206) is snapped into the bottom end of the cross support (205) at equal intervals. A sealing slide cover (207) is snapped into the bottom end of the electric hydraulic push rod (206). The sealing slide cover (207) is fitted with a clamping cylinder (208) in the middle. Both ends of the clamping cylinder (208) are connected to adjusting push rods (209) by threads at equal intervals. One end of the two adjusting push rods (209) is fitted with a clamping arc plate (210), and the other end of the two adjusting push rods (209) is fitted with a knob gear (211).

2. The device for quantitative characterization of cross-scale geothermal reservoir fracture network and evaluation of thermal extraction efficiency according to claim 1, characterized in that: A gap is left between the detachable inner cylinder (202) and the precast curing cylinder (201), and the outer side of the demolding base (203) is in contact with the inner wall of the precast curing cylinder (201).

3. The device for quantitative characterization of cross-scale geothermal reservoir fracture network and evaluation of thermal extraction efficiency according to claim 1, characterized in that: The sealing slide cover (207) has an injection port at its top. The two adjusting push rods (209) on the same side have opposite rotation directions on their outer threads, and the two knob gears (211) on the same side mesh with each other.

4. The device for quantitative characterization of fracture networks and evaluation of thermal extraction efficiency in multi-scale geothermal reservoirs according to claim 1, characterized in that: The top of the clamping cylinder (208) is fitted with a telescopic slide tube (212), and an anti-deviation sleeve (213) is sleeved on the outside of the telescopic slide tube (212). The top of the anti-deviation sleeve (213) is connected to a water delivery hose (214) by a thread, and a water pump (215) is installed on the outside of the water delivery hose (214). The double-layer base frame (1) is equipped with a deionized water tank (216), and a recycling circulation pipe (217) is connected between the deionized water tank (216) and the prefabricated curing cylinder (201).

5. The device for quantitative characterization of cross-scale geothermal reservoir fracture network and evaluation of thermal extraction efficiency according to claim 4, characterized in that: The top of the anti-deviation sleeve (213) passes through the top of the cross support (205), and the water pump (215) and the electric hydraulic push rod (206) are both powered by an external power source.

6. The device for quantitative characterization of cross-scale geothermal reservoir fracture network and evaluation of thermal extraction efficiency according to claim 4, characterized in that: One end of the water delivery hose (214) is connected to one end of the deionized water tank (216), and a valve is installed inside the recycling pipe (217).

7. The device for quantitative characterization of fracture networks and evaluation of thermal extraction efficiency in multi-scale geothermal reservoirs according to claim 1, characterized in that: The top of the double-layer base frame (1) is provided with a heat extraction simulation and waste heat utilization mechanism (3), which includes a high-temperature and high-pressure reactor (301). The top of the double-layer base frame (1) is equipped with a high-temperature and high-pressure reactor (301). The high-temperature and high-pressure reactor (301) is connected to an annular support (302). The annular support (302) is equidistantly fitted with internal threaded cylinders (303), and the internal threaded cylinders (303) are connected to a positioning top rod (304) by threads. The annular support (302) has annular cavities (306) equidistantly arranged inside, and an electric heating plate (307) is installed equidistantly inside one annular cavity (306). The double-layer base frame (1) is equipped with a circulating water tank (308). A water supply pipe (309) is connected to one end of the circulating water tank (308), and a temperature measuring water injection pipe (310) is connected to the top of the circulating water tank (308). A water supply pump (311) is installed on the outside of both the water supply pipe (309) and the temperature measuring water injection pipe (310). Water temperature sensors (305) are installed on the inner wall of the temperature measuring water injection pipe (310) and the inner wall of the annular bracket (302). One end of the high-temperature and high-pressure reactor (301) is connected to a heat-insulating water pipe (312), and the bottom end of the heat-insulating water pipe (312) is connected to a flow direction regulating valve cylinder (313). A connecting pipe (314) is connected between the prefabricated curing cylinder (201) and the flow direction regulating valve (313). One end of the double-layer base frame (1) is fitted with a heat dissipation fin (315), the top end of the heat dissipation fin (315) is fitted with a three-way pipe (316), and the outside of the three-way pipe (316) is symmetrically fitted with a drain pipe (317). The bottom end of the heat dissipation fin (315) is fitted with an inlet pipe (318).

8. The device for quantitative characterization of fracture networks and evaluation of thermal extraction efficiency in multi-scale geothermal reservoirs according to claim 7, characterized in that: One end of the positioning rod (304) is rotatably connected to a rubber pad, the other end of the water supply pipe (309) is connected to the outside of the high temperature and high pressure reactor (301), and the top end of the temperature measuring water injection pipe (310) is connected to the bottom end of the high temperature and high pressure reactor (301).

9. The device for quantitative characterization of fracture networks and evaluation of thermal extraction efficiency in multi-scale geothermal reservoirs according to claim 7, characterized in that: The water temperature detection sensors (305) are equidistantly distributed at the top of the inner wall of the annular bracket (302). Both the water supply pump (311) and the water temperature detection sensors (305) are powered by an internal power source.

10. The device for quantitative characterization of fracture networks and evaluation of thermal extraction efficiency in multi-scale geothermal reservoirs according to claim 7, characterized in that: One of the drain pipes (317) is connected at one end to the outside of the flow direction regulating valve cylinder (313), and the other drain pipe (317) is connected at one end to the outside of the prefabricated curing cylinder (201).

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