Device for exploiting dry hot rock geothermal energy based on seawater working medium and installation method thereof

Abstract

The application discloses a device for exploiting dry hot rock geothermal energy based on seawater working medium and a mounting method thereof. The device comprises a geothermal energy collecting assembly, a steam generator, a steam power generation assembly, a condenser and a heat exchange assembly. The steam generator is connected to the geothermal energy collecting assembly, the steam power generation assembly is connected to the steam generator, the condenser is connected to the steam power generation assembly, the heat exchange assembly is used for absorbing the heat energy of the geothermal layer, one end of the heat exchange assembly is connected to the condenser, the other end of the heat exchange assembly is connected to the steam generator, and a control system is electrically connected with the geothermal energy collecting assembly, the steam generator, the steam power generation assembly, the condenser and the heat exchange assembly. The working medium after power generation is recycled, direct discharge of the working medium after power generation is avoided, the power generation capacity of the steam power generation assembly is improved, and the economic benefit of the dry hot rock exploitation is improved.

Description

Technical Field

[0001] This invention relates to the field of hot dry rock mining technology, and more particularly to a device and its installation method for mining hot dry rock geothermal energy based on seawater working fluid. Background Technology

[0002] Hot dry rock has advantages such as large reserves, wide distribution, and clean, low-carbon characteristics, making it one of the most promising types of geothermal resources. The traditional EGS dual-well extraction model involves modifying the hot dry rock reservoir by injecting high-pressure water into at least one injection well, enhancing its permeability and fluid flow. Low-temperature freshwater is then driven through the modified reservoir network to extract thermal energy, and the heat-carrying working fluid is extracted through designated production wells to generate electricity.

[0003] The aforementioned existing technologies mainly rely on freshwater as the heat exchange medium to extract geothermal energy from hot dry rock. However, freshwater resources in coastal areas or on marine islands are depleted, while seawater is inexhaustible. Currently, there is a lack of technologies and methods for extracting geothermal resources from hot dry rock using seawater. Furthermore, heat exchange and power generation devices lack consideration for seawater corrosion resistance and the filtration of harmful substances, which can easily lead to environmental pollution and waste of the working fluid, resulting in reduced economic benefits from hot dry rock development.

[0004] Therefore, existing technologies need to be improved. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a device and its installation method for mining hot dry rock geothermal energy based on seawater working medium, in order to address the above-mentioned defects of the prior art. The invention aims to solve the problems of corrosion of equipment by heat exchange working medium, environmental pollution and reduced economic benefits of hot dry rock mining in the prior art.

[0006] The technical solution adopted by this invention to solve the technical problem is as follows:

[0007] A device for extracting geothermal energy from hot dry rock using seawater as a working medium, comprising:

[0008] Geothermal energy collection components are used to inject seawater to collect geothermal energy;

[0009] A steam generator is connected to the geothermal energy collection assembly;

[0010] A steam power generation unit is connected to the steam generator;

[0011] A condenser is connected to the steam power generation unit;

[0012] A heat exchange component, used for absorbing geothermal energy, is connected at one end to the condenser and at the other end to the steam generator;

[0013] The control system is electrically connected to the geothermal energy collection assembly, the steam generator, the steam power generation assembly, the condenser, and the heat exchange assembly.

[0014] Optionally, the heat exchange assembly includes:

[0015] At least two heat exchangers are located at different depths of the geothermal layer, and adjacent heat exchangers are interconnected.

[0016] A return pipe, one end of which is connected to the steam generator;

[0017] The heat exchanger located at the top layer is connected to the condenser, the heat exchanger located at the bottom layer is connected to the return pipe, and the heat exchanger is electrically connected to the control system.

[0018] Optionally, the geothermal energy collection assembly includes an injection well and a production well, with an artificial slot network between the injection well and the production well. The artificial slot network includes a plurality of slots. The heat exchanger is located between the injection well and the production well. The heat exchanger includes a cold source medium inlet, a cold source medium outlet, a heat exchange medium inlet, and a heat exchange medium outlet. The uppermost cold source medium inlet is connected to the condenser, and the lowermost cold source medium outlet is connected to the return pipe. The heat exchange medium inlet of each heat exchanger is connected to a single slot, and all the heat exchange medium outlets of the heat exchanger are connected to the ground heating equipment.

[0019] Optionally, the connecting pipes between adjacent heat exchangers, the connecting pipes between the heat exchangers and the return pipes, the connecting pipes between the heat exchangers and the floor heating equipment, and the return pipes are all provided with heat insulation layers.

[0020] Optionally, the injection well includes: a first vertical section and a first horizontal section, one end of the first vertical section is connected to seawater, the other end is connected to the first horizontal section and extends to the geothermal layer, and several first perforations are arranged on the first horizontal section;

[0021] The production well includes: a second vertical section and a second horizontal section. One end of the second vertical section is connected to the steam generator, and the other end is connected to the second horizontal section and extends into the rock layer. Several second perforations are arranged on the second horizontal section.

[0022] The first perforation and the second perforation are connected through the artificial slit network.

[0023] Optionally, a filter assembly for filtering impurities is provided inside the production well.

[0024] Optionally, the filtration assembly includes a quartz sand filter layer, an activated carbon filter layer, and a resin filter layer, wherein the quartz sand filter layer, the activated carbon filter layer, and the resin filter layer are fixed in the production well from bottom to top.

[0025] Optionally, the steam power generation assembly includes:

[0026] A steam turbine generator, one end of which is connected to the steam generator and the other end of which is connected to the condenser;

[0027] The steam turbine generator is electrically connected to the control system.

[0028] An installation method for an apparatus based on seawater extraction of hot dry rock geothermal energy as described in any of the above technical solutions, the method comprising:

[0029] Based on geological exploration information, the location of the target hot dry rock reservoir was determined;

[0030] Based on the location of the target hot dry rock reservoir, determine the installation location of the geothermal energy harvesting components;

[0031] According to the installation location of the geothermal energy collection component, the steam generator, steam power generation component and condenser are installed on the ground layer, and the heat exchange component is pre-embedded in the geothermal layer. The geothermal energy collection component is connected to the steam generator, and the steam generator, the steam power generation component, the condenser and the heat exchange component are connected in sequence through pipelines to form a loop.

[0032] Optionally, the step of installing the steam generator, steam power generation component, and condenser to the ground layer according to the installation location of the geothermal energy collection component, and pre-embedding the heat exchange component in the geothermal layer specifically includes:

[0033] An artificial platform was constructed on the ground layer around the location of the production well.

[0034] The steam generator, steam power generation unit, and condenser are installed on the artificial platform. The steam generator is connected to the steam power generation unit through pipelines. The low-temperature steam generated by the steam power generation unit is connected to the condenser through pipelines.

[0035] A vertical deep well is drilled at a designated detection location, and multiple heat exchangers are pre-embedded in the geothermal layer. Each heat exchanger is located at a different depth within the same vertical deep well. The heat exchanger at the top layer is connected to the condenser through a pipeline, and the heat exchanger at the bottom layer is connected to the return pipe through a pipeline. The return pipe is then connected to the steam generator pipeline, thus forming a circulation loop.

[0036] Beneficial effects:

[0037] This invention provides a device and its installation method for mining geothermal energy from hot dry rock using seawater as the working medium. The device condenses the low-temperature steam working medium generated by the steam generator into liquid seawater via a condenser. This liquid seawater is then passed through a heat exchanger embedded in the geothermal layer to form a high-temperature liquid. The high-temperature liquid is then directly transported to a steam generator, where it is converted into high-temperature steam and recycled by the steam generator. This avoids the direct discharge and waste of the working medium after power generation, thereby increasing the power output of the steam generator and improving the economic benefits of hot dry rock mining. Furthermore, using seawater as the heat exchange medium solves the problem of excessive freshwater consumption in conventional water circulation methods, effectively conserving freshwater resources and achieving green mining. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the device for extracting geothermal energy from dry hot rock according to the present invention;

[0039] Figure 2 This is a schematic diagram of the method flow structure of the present invention.

[0040] Explanation of reference numerals in the attached figures:

[0041] 100. Geothermal layer; 200. Rock layer; 300. Surface layer; 400. Steam turbine generator; 500. Heating pipe; 600. Steam generator; 700. Condenser; 800. Surface heating equipment; 900. Heat exchanger; 1000. Seawater storage equipment; 1100. Injection well; 1110. First vertical section; 1120. First horizontal section; 1130. First perforation; 1200. Production well; 1210. Second vertical section; 1220. Second horizontal section; 1230. Second perforation; 1300. First water pump; 1400. Third water pump; 1500. Fourth water pump; 1600. Fifth water pump; 1700. Filter assembly. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0043] Currently, the mining of hot dry rock requires a large amount of fresh water. However, fresh water resources are scarce in coastal areas or on islands and reefs, and heat exchange media cannot be fully utilized, resulting in high costs for hot dry rock mining in coastal areas or on islands and reefs. Based on this, the present invention improves the existing technology.

[0044] Please see Figure 1 This invention provides some preferred embodiments of a device for extracting geothermal energy from hot dry rock using seawater as a working medium. For example... Figure 1As shown, an apparatus for extracting geothermal energy from hot dry rock based on seawater as a working fluid includes: a geothermal energy collection component, a steam generator 600, a steam power generation component, a condenser 700, a heat exchange component, and a control system. The geothermal energy collection component is used to inject seawater to collect geothermal energy. The steam generator 600 is connected to the geothermal energy collection component. The steam power generation component is connected to the steam generator 600. The condenser 700 is connected to the steam power generation component and is used to condense the energy into liquid. The heat exchange component is used to absorb geothermal energy and exchange heat, with one end connected to the condenser 700 and the other end connected to the steam generator 600. The steam generator 600, the steam power generation component, the condenser 700, and the heat exchange component are all electrically connected to the control system. The injected liquid in the injection well 1100 is seawater.

[0045] It is worth noting that, such as Figure 1 As shown, the hot dry rock includes a geothermal layer 100 (hot dry rock layer), a rock layer 200 (rock on the surface of the hot dry rock), and a surface layer 300 (the location where the equipment is installed on the ground). Generally, the surface of the hot dry rock is uneven. To ensure stable operation of the equipment, it is installed on an artificially constructed platform (located above the rock layer 200), thereby ensuring the stable operation of each piece of equipment. The geothermal energy collection component is used to inject seawater to collect geothermal energy. The steam generator 600, steam power generation component, condenser 700, and heat exchange component form a connected loop. The control system is used to control the opening and closing of the above-mentioned equipment. The control system is a hot dry rock mining control system, including a control terminal for communication connection of each piece of equipment for convenient control.

[0046] It should be noted that, since the steam generator 600 needs to extract seawater working medium heated by dry hot rock from the geothermal energy collection component, in order to facilitate the extraction of seawater working medium heated by dry hot rock by the steam generator 600, the steam generator 600 and the geothermal energy collection component are connected as a first pipeline, and a first water pump 1300 is installed on the first pipeline. The first water pump 1300 is connected to the control system.

[0047] This invention injects seawater into a geothermal energy collection component. The heated seawater is then pumped by a first pump 1300 into a steam generator 600. The steam generator 600 converts the high-temperature seawater into high-temperature steam, which is then transported to a steam power generation component to generate electricity. The low-temperature steam after power generation is condensed into liquid seawater by a condenser 700 and then heated in a heat exchange component. The heated liquid seawater becomes high-temperature seawater and is then injected back into the steam generator 600. This ensures full utilization of the low-temperature steam after power generation, significantly improving the economic efficiency of hot dry rock mining. Furthermore, because the seawater heated by the heat exchange component easily reaches the rated feedwater temperature required by the steam generator 600, combined with the high-temperature liquid absorbed by the geothermal energy collection component, the amount of high-temperature steam generated by the steam generator 600 is greatly increased, thereby significantly increasing the power generation of the steam power generation component. This invention also uses seawater as the heat exchange medium, achieving a green mining process that saves freshwater, reduces costs, and minimizes environmental pollution compared to existing devices that use freshwater to mine hot dry rock.

[0048] In a preferred embodiment of the present invention, such as Figure 1 As shown, the heat exchange assembly includes at least two heat exchangers 900 and a return pipe. The two heat exchangers 900 are located at different depths of the geothermal layer 100, and adjacent heat exchangers 900 are interconnected. One end of the return pipe is connected to the lowest heat exchanger 900, and the other end is connected to the steam generator 600. The highest heat exchanger 900 is connected to the condenser 700, and the heat exchanger 900 is electrically connected to the control system.

[0049] Specifically, the number of heat exchangers 900 is preferably two. Both heat exchangers 900 can be installed at different depths within the same geothermal layer 100 via a single shaft, reducing installation difficulty and cost. It is understood that the steam generator 600 produces the most steam, has the best conversion efficiency, and consumes the least electricity at its rated feedwater temperature. By setting up multiple heat exchangers 900, the required feedwater temperature for the steam generator 600 is achieved through multiple heat exchanges, thereby improving the steam conversion efficiency of the steam generator 600.

[0050] In a preferred embodiment of the present invention, such as Figure 1As shown, the geothermal energy collection assembly includes an injection well 1100 and a production well 1200. An artificial slot network is provided between the injection well 1100 and the production well 1200. The artificial slot network includes a plurality of slots. The heat exchanger 900 is located between the injection well 1100 and the production well 1200. The heat exchanger 900 includes a cold source medium inlet, a cold source medium outlet, a heat exchange medium inlet, and a heat exchange medium outlet. The uppermost cold source medium inlet is connected to the condenser 700, and the lowermost cold source medium outlet is connected to the return pipe. The heat exchange medium inlet of each heat exchanger 900 is connected to a single slot, and all the heat exchange medium outlets of the heat exchanger 900 are connected to the ground heating equipment 800.

[0051] Specifically, an injection well 1100 is drilled in a geothermal layer 100 with a target temperature of 150 degrees Celsius. A production well 1200 is installed in the rock layer 200 (i.e., the surface of the geothermal layer) through which the injection well 1100 flows. Preferably, there are two production wells 1200. An artificial fracture network refers to artificially created geothermal reservoir fractures used to connect the injection well 1100 and the production well 1200. This allows the seawater working medium in the injection well 1100 to flow through the geothermal layer 100 and then be extracted by the production well 1200. A heat exchanger 900 is installed in the geothermal layer 100 between the injection well 1100 and the production well 1200. The heat exchange medium inlet of each heat exchanger 900 is connected to a fracture in the individual artificial fracture network, enabling heat exchange using the extracted geothermal seawater working medium. The cooled seawater working medium after heat exchange is then recycled by the ground heating equipment 800, reducing equipment operating costs and significantly improving economic efficiency. Understandably, the ground heating equipment 800 refers to heating equipment for residential use, requiring a temperature between 80-100 degrees Celsius. The temperature of conventional geothermal seawater working fluid is between 150-350 degrees Celsius, and the seawater working fluid after heat exchange is also close to 100 degrees Celsius, which perfectly matches the temperature requirements of the ground heating equipment 800. It can also prevent the working fluid after heat exchange from flowing into the production well 1200 and affecting the conversion efficiency of the steam generator 600.

[0052] In another embodiment, such as Figure 1 As shown, the connecting pipes between adjacent heat exchangers 900, the connecting pipes between heat exchangers 900 and the return pipe, the connecting pipes between heat exchangers 900 and the floor heating equipment 800, and the return pipe are all provided with heat insulation layers.

[0053] Specifically, the heat exchangers 900 are connected to each other via a second pipe, the heat exchangers 900 are connected to the return pipe via a third pipe, and the heat exchangers 900 are connected to the floor heating equipment 800 via a fourth pipe. The second, third, and fourth pipes, as well as the return pipe, are all equipped with thermal insulation layers to prevent heat loss. More specifically, the thermal insulation layers are made of ceramic fiber material.

[0054] Furthermore, a third water pump 1400 is installed on the third pipeline to extract the cold source working fluid after heat exchange into the steam generator 600, and a fourth water pump 1500 is installed on the fourth pipeline to extract the seawater working fluid after heat exchange into the ground heating equipment 800 for recycling.

[0055] In another preferred embodiment, such as Figure 1 As shown, the injection well 1100 includes a first vertical section 1110 and a first horizontal section 1120. One end of the first vertical section 1110 is connected to seawater, and the other end is connected to the first horizontal section 1120 and extends to the geothermal layer 100. Several first perforations 1130 are arranged on the first horizontal section 1120. The production well 1200 includes a second vertical section 1210 and a second horizontal section 1220. One end of the second vertical section 1210 is connected to the steam generator 600, and the other end is connected to the second horizontal section 1220 and extends to the rock layer 200. Several second perforations 1230 are arranged on the second horizontal section 1220. The first perforations 1130 and the second perforations 1230 are connected through the artificial slotted network.

[0056] Specifically, perforations are made in the first horizontal section 1120 of the injection well 1100 and the second horizontal section 1220 of the production well 1200 using perforation tools, resulting in first perforations 1130 and second perforations 1230. Multiple first perforations 1130 and second perforations 1230 are created. The reservoir is stimulated using periodic hydraulic fracturing technology in the first perforation 1130, resulting in an artificial fracture network. The second perforation 1230 is then connected to the surface of the geothermal layer 100 through which the artificial fracture network passes, allowing the extraction of seawater working fluid after heat exchange within the geothermal layer 100. This method, by artificially creating a fracture network, provides easier control over the direction and location of the geothermal reservoir fractures compared to artificial fracture networks created using high-pressure water fracturing, thus facilitating the extraction and utilization of geothermal energy.

[0057] It should be noted that the seawater working medium after the geothermal layer 100 is easily filled with impurities and particulate matter. The steam generator 600 has high requirements for water quality. Water quality will cause scale to easily form in the water pipes and water tank inside the steam generator 600, affecting the thermal efficiency and service life of the steam generator 600.

[0058] In another embodiment, such as Figure 1 As shown, a filter assembly 1700 for filtering impurities is installed inside the production well 1200.

[0059] Specifically, the filter assembly 1700 includes a quartz sand filter layer, an activated carbon filter layer, and a resin filter layer, which are fixed in the production well 1200 from bottom to top.

[0060] Furthermore, a quartz sand filter layer, an activated carbon filter layer, and a resin filter layer are installed in the production well 1200 located below the first water pump 1300. The quartz sand layer is the bottom layer, and the resin layer is the top layer. The quartz sand filter layer is used to filter silt, impurities, colloids, particulate matter, and suspended solids; the activated carbon filter layer is used to filter odors and discoloration; and the resin filter layer is used to filter calcium and magnesium ions. In this embodiment, all filter layers are installed within the production well 1200, reducing heat loss during filtration. Through layer-by-layer filtration, the water quality of the extracted seawater is more likely to meet standards, thereby improving the service life and thermal efficiency of the steam generator 600, and ultimately increasing the power generation efficiency of the steam power generation assembly.

[0061] Furthermore, the control system also includes a display terminal for displaying data from the steam generator 600. For example, a temperature sensor and a corrosion level sensor are installed inside the steam generator 600 and connected to the control system to display in real time the temperature during the reaction inside the steam generator 600 and the degree of seawater corrosion, thereby monitoring the steam generator 600 and facilitating timely maintenance.

[0062] In another embodiment, please refer to Figure 1 As shown, the steam power generation assembly includes a steam turbine generator 400, one end of which is connected to the steam generator 600 and the other end of which is connected to the condenser 700. The steam turbine generator 400 is electrically connected to the control system.

[0063] Specifically, the steam turbine generator 400 is a device that converts thermal energy into electrical energy, enabling full utilization of the thermal energy of dry hot rock.

[0064] Furthermore, the pipe connecting the steam generator 600 and the steam turbine generator 400 is a fifth pipe, and a heating pipe 500 is installed on the fifth pipe. The heating pipe 500 is used to preheat the steam to improve the power generation efficiency of the steam turbine generator 400.

[0065] Based on all the above embodiments, see Figure 2 As shown, the present invention also provides an installation method for a device based on seawater extraction of hot dry rock geothermal energy as described in any of the above technical solutions, the method comprising the following steps:

[0066] S100. Based on geological exploration information, determine the location of the target hot dry rock reservoir;

[0067] Specifically, by using detection equipment to examine the hot dry rock area, the depth range, geological background, and geostress conditions were determined. A geothermal layer 100, rich in hot dry rock resources at a target temperature of 150 degrees Celsius, was selected.

[0068] S200. Determine the installation location of the geothermal energy collection component based on the location of the target hot dry rock reservoir;

[0069] The S200 step specifically includes:

[0070] S210. Drilling injection well 1100 using drilling tools, wherein injection well 1100 includes a first vertical section 1110 and a first horizontal section 1120;

[0071] S220. The first horizontal section 1120 of the injection well 1100 is perforated by a perforation tool to obtain the first perforation 1130.

[0072] S230. The first perforation 1130 is modified by periodic hydraulic fracturing technology to form an artificial fracture network.

[0073] S240. Drill two production wells 1200 in the rock layer 200 (i.e., the surface of the geothermal layer) through which the seawater working medium of the injection well 1100 flows. The production wells 1200 include a second vertical section 1210 and a second horizontal section 1220.

[0074] S250. The second horizontal section 1220 of the two production wells 1200 is perforated by a perforation tool to obtain a second perforation 1230; wherein, the second perforation 1230 is connected to the thermal reservoir fracture of the artificial fracture network.

[0075] S260, Install the filter assembly 1700 into the production well 1200.

[0076] S300. According to the installation position of the geothermal energy collection component, the steam generator 600, the steam power generation component and the condenser 700 are installed to the ground layer 300. The heat exchange component is pre-embedded in the geothermal layer 100. The geothermal energy collection component is connected to the steam generator 600. The steam generator 600, the steam power generation component, the condenser 700 and the heat exchange component are connected in sequence through pipelines to form a connected loop.

[0077] The steps in S300 specifically include:

[0078] S310. Construct an artificial platform around the ground layer 300 where the production well 1200 is located;

[0079] S320. Install the steam generator 600, the steam power generation unit, and the condenser 700 onto the manual platform. The steam generator 600 is connected to the steam power generation unit through a pipeline. The low-temperature steam generated by the steam power generation unit is connected to the condenser 700 through a pipeline.

[0080] S330. Drill a vertical deep well located between the production well and the injection well. Embed multiple heat exchangers 900 into the geothermal layer 100. Each heat exchanger 900 is located at a different depth within the same vertical deep well. The uppermost heat exchanger 900 is connected to the condenser 700 via a pipeline, and the lowermost heat exchanger 900 is connected to the return pipe via a pipeline. The return pipe is then connected to the steam generator 600, thus forming a circulation loop.

[0081] Furthermore, the step of pre-embedding multiple heat exchangers 900 within the geothermal layer 100 includes:

[0082] S341. The heat exchanger includes a cold source medium inlet, a cold source medium outlet, a heat exchange medium inlet, and a heat exchange medium outlet. The uppermost cold source medium inlet is connected to the condenser, and the lowermost cold source medium outlet is connected to the return pipe. The heat exchange medium inlet of each heat exchanger is connected to a single gap, and all the heat exchange medium outlets of the heat exchanger are connected to the floor heating equipment.

[0083] The present invention also provides a control system for controlling the injection of seawater into the geothermal energy collection component for extraction, and for controlling the movement of various components, which will not be elaborated further here.

[0084] In addition, to facilitate the use of seawater, seawater is first pumped to seawater storage device 1000, which is installed on an artificial platform. Seawater storage device 1000 is connected to injection well 1100 via fifth pump 1600.

[0085] The working principle is as follows: Seawater is drawn into injection well 1100 by the fifth pump 1600. In injection well 1100, it absorbs geothermal energy and enters the first perforation 1130. Through the first perforation 1130, it flows to the artificial fissure network, where it absorbs geothermal energy from the geothermal layer 100 again and is transformed into high-temperature seawater. Then, it is filtered by the filter assembly 1700 in production well 1200 and then drawn into steam generator 600 by the first pump 1300 on production well 1200. Steam generator 600 transforms the high-temperature seawater into high-temperature steam. The high-temperature steam is sent to steam turbine generator 400 to generate electricity. The low-temperature steam after power generation is condensed into liquid seawater by condenser 700. The liquid seawater then absorbs heat energy through heat exchanger 900 and is transformed into high-temperature seawater. Finally, it flows back into steam generator 600, and the cycle repeats.

[0086] In summary, this invention provides a device and its installation method for extracting geothermal energy from hot dry rock using seawater as the working medium. By fully utilizing the low-temperature steam working medium generated after power generation, it can not only increase the steam output of the steam generator but also improve the power generation of the steam turbine generator, thereby increasing the economic benefits of hot dry rock extraction. Furthermore, using seawater as the heat exchange medium can solve the problem of high water consumption in ordinary water circulation methods, making it suitable for areas with water shortages.

[0087] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A device for extracting geothermal energy from hot dry rock using seawater as a working medium, characterized in that, include: Geothermal energy collection components are used to inject seawater to collect geothermal energy; A steam generator is connected to the geothermal energy collection assembly; A steam power generation unit is connected to the steam generator; A condenser is connected to the steam power generation assembly; A heat exchange component, used for absorbing geothermal energy, is connected at one end to the condenser and at the other end to the steam generator; The control system is electrically connected to the geothermal energy collection assembly, the steam generator, the steam power generation assembly, the condenser, and the heat exchange assembly. The heat exchange assembly includes: At least two heat exchangers are located at different depths of the geothermal layer, and adjacent heat exchangers are interconnected. A return pipe, one end of which is connected to the steam generator; The heat exchanger located at the top layer is connected to the condenser, the heat exchanger located at the bottom layer is connected to the return pipe, and the heat exchanger is electrically connected to the control system. The geothermal energy collection assembly includes an injection well and a production well. An artificial slot network is provided between the injection well and the production well. The artificial slot network includes a number of slots. The heat exchanger is located between the injection well and the production well. The heat exchanger includes a cold source medium inlet, a cold source medium outlet, a heat exchange medium inlet, and a heat exchange medium outlet. The uppermost cold source medium inlet is connected to the condenser, and the lowermost cold source medium outlet is connected to the return pipe. The heat exchange medium inlet of each heat exchanger is connected to a single slot, and all the heat exchange medium outlets of the heat exchanger are connected to the ground heating equipment.

2. The device for extracting geothermal energy from hot dry rock based on seawater working fluid according to claim 1, characterized in that, The connecting pipes between adjacent heat exchangers, the connecting pipes between the heat exchangers and the return pipes, the connecting pipes between the heat exchangers and the floor heating equipment, and the return pipes are all provided with heat insulation layers.

3. The device for extracting geothermal energy from hot dry rock based on seawater working fluid according to claim 1, characterized in that, The injection well includes: a first vertical section and a first horizontal section, one end of the first vertical section is connected to seawater, the other end is connected to the first horizontal section and extends to the geothermal layer, and several first perforations are arranged on the first horizontal section; The production well includes: a second vertical section and a second horizontal section. One end of the second vertical section is connected to the steam generator, and the other end is connected to the second horizontal section and extends into the rock layer. Several second perforations are arranged on the second horizontal section. The first perforation and the second perforation are connected through the artificial slit network.

4. The device for extracting geothermal energy from hot dry rock based on seawater working fluid according to claim 3, characterized in that, The production well is equipped with a filter assembly for filtering impurities.

5. The device for extracting geothermal energy from hot dry rock based on seawater working fluid according to claim 4, characterized in that, The filtration assembly includes a quartz sand filter layer, an activated carbon filter layer, and a resin filter layer, which are fixed in the production well from bottom to top.

6. The device for extracting geothermal energy from hot dry rock based on seawater working fluid according to claim 1, characterized in that, The steam power generation assembly includes: A steam turbine generator, one end of which is connected to the steam generator and the other end of which is connected to the condenser; The steam turbine generator is electrically connected to the control system.

7. An installation method for a device for extracting geothermal energy from hot dry rock based on seawater working fluid as described in any one of claims 1 to 6, characterized in that, The method includes: Based on geological exploration information, the location of the target hot dry rock reservoir was determined; Based on the location of the target hot dry rock reservoir, determine the installation location of the geothermal energy harvesting components; According to the installation location of the geothermal energy collection component, the steam generator, steam power generation component and condenser are installed on the ground layer, and the heat exchange component is pre-embedded in the geothermal layer. The geothermal energy collection component is connected to the steam generator, and the steam generator, the steam power generation component, the condenser and the heat exchange component are connected in sequence through pipelines to form a connected loop.

8. The installation method of the device for extracting geothermal energy from hot dry rock based on seawater working fluid according to claim 7, characterized in that, The step of installing the steam generator, steam power generation component, and condenser to the ground layer according to the installation location of the geothermal energy collection component, and pre-embedding the heat exchange component in the geothermal layer specifically includes: An artificial platform was constructed around the surface layer where the production well was located; The steam generator, steam power generation unit, and condenser are installed on the artificial platform. The steam generator is connected to the steam power generation unit through pipelines. The low-temperature steam generated by the steam power generation unit is connected to the condenser through pipelines. A vertical deep well is drilled at a designated detection location, between the production well and the injection well. Multiple heat exchangers are pre-embedded in the geothermal layer, with each heat exchanger located at a different depth within the same vertical deep well. The uppermost heat exchanger is connected to the condenser via pipelines, while the lowermost heat exchanger is connected to the return pipe via pipelines. The return pipe is then connected to the steam generator pipelines, thus forming a circulation loop.

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