Electric heat supply method and system based on high-temperature geothermal heat

Abstract

An electric heat supply method and system based on high-temperature geothermal heat. The system comprises: a hot dry rock production well (3), a hot dry rock reinjection well (4), a geothermal power generation device (001), a dual working medium power generation device (002), a heat supply device (003), a first heat exchanger (10), a second heat exchanger (14), and a third heat exchanger (21). The geothermal power generation device (001) is connected to the hot dry rock production well (3), and is connected to the dual working medium power generation device (002) by means of the first heat exchanger (10), and is connected to the heat supply device (003) by means of the second heat exchanger (14). The dual working medium power generation device (002) is connected to the heat supply device (003) by means of the third heat exchanger (21). The second heat exchanger (14) is connected to the hot dry rock reinjection well (4). The geothermal power generation device (001) uses a geothermal medium for power generation. The dual working medium power generation device (002) absorbs heat by means of the first heat exchanger (10) for power generation. The heat supply device (003) absorbs heat by means of the second heat exchanger (14) and the third heat exchanger (21) for heat supply. The cooled geothermal medium is reinjected into a hot dry rock stratum below the ground level by means of the hot dry rock reinjection well (4). Heat resources of the geothermal medium are fully utilized, the power generation capacity is increased, and the utilization rate of resources is increased.

Description

A method and system for supplying electric heat based on high-temperature geothermal energy Technical Field

[0001] The present invention relates to the field of new energy application technology, and in particular to a method and system for supplying electric heat based on high-temperature geothermal energy. Background Art

[0002] Under the dual pressures of the global energy crisis and environmental pollution, the development of new, environmentally friendly, and abundant alternative energy sources has become a key focus of current energy research. Among these, high-temperature geothermal resources, due to their exceptional cleanliness, operational stability, and widespread spatial distribution, have become a key area of ​​research and development for this new clean energy source.

[0003] High-temperature geothermal resources primarily refer to hydrothermal and hot dry rock geothermal resources with temperatures exceeding 150°C. Currently, power generation is solely based on dry steam or duplex heating, representing only primary utilization. This inadequately utilizes the heat from high-temperature geothermal resources, reduces power generation, and results in resource waste. Summary of the Invention

[0004] In view of this, an embodiment of the present invention provides a method and system for supplying electric heat based on high-temperature geothermal energy to solve the problem of insufficient heat utilization of high-temperature geothermal resources.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0006] A first aspect of an embodiment of the present invention discloses a high-temperature geothermal electric heat supply system, the system comprising: a hot dry rock production well, a hot dry rock reinjection well, a geothermal power generation device, a dual-fluid power generation device, a heat supply device, a first heat exchanger, a second heat exchanger, and a third heat exchanger;

[0007] The hot dry rock mining well is set in the hot dry rock layer below the ground level, and the hot dry rock mining well is connected to the input end of the geothermal power generation device through a transmission pipeline; the output end of the geothermal power generation device is connected to the first heat exchanger;

[0008] The first heat exchanger is connected to the second heat exchanger; the second heat exchanger is connected to the hot dry rock reinjection well, and the hot dry rock reinjection well is set in the hot dry rock layer below the ground level;

[0009] The dual-fluid power generation device is connected to the first heat exchanger; the dual-fluid power generation device is connected to the heat supply device through the third heat exchanger; the heat supply device is connected to the second heat exchanger;

[0010] The hot dry rock mining well is used to collect geothermal media, and the geothermal media includes hydrothermal media or hot dry rock media;

[0011] The geothermal power generation device is used to generate electricity using the geothermal medium;

[0012] The dual-fluid power generation device is used to absorb the heat of the geothermal medium in the first heat exchanger, heat the working fluid, and generate electricity using the heated working fluid;

[0013] The heat supply device is used to absorb the heat of the geothermal medium in the second heat exchanger and the heat of the working fluid in the third heat exchanger to heat the heat collecting liquid, and use the heated heat collecting liquid to provide heat;

[0014] The hot dry rock reinjection well is used to reinject the cooled geothermal medium into the hot dry rock layer below the ground level.

[0015] Preferably, the geothermal power generation device comprises: a first power generation module and a gas-liquid separator;

[0016] The input end of the gas-liquid separator is connected to the hot dry rock mining well through a delivery pipeline, and the first output end of the gas-liquid separator is connected to the input end of the first power generation module through a delivery pipeline;

[0017] The second output end of the gas-liquid separator and the output end of the first power generation module are connected via a delivery pipeline, and the common end of the connection is connected to the heat medium inlet of the first heat exchanger;

[0018] The gas-liquid separator is used to separate the geothermal medium into gas and liquid, and transport the separated high-temperature gas to the first power generation module, so that the first power generation module uses the high-temperature gas to generate electricity.

[0019] Preferably, the first power generation module includes: a first steam turbine and a first generator;

[0020] The input end of the first steam turbine is connected to the first output end of the gas-liquid separator through a delivery pipeline, and the output end of the first steam turbine is connected to the second output end of the gas-liquid separator through a delivery pipeline; one end of the first steam turbine is connected to the first generator;

[0021] The first steam turbine is configured to rotate based on the high-temperature gas to drive the first generator to generate electricity.

[0022] Preferably, the dual-fluid power generation device includes a second power generation module and a working fluid pump;

[0023] The input end of the second power generation module is connected to the refrigerant outlet of the first heat exchanger through a delivery pipeline, and the output end of the second power generation module is connected to the heat medium inlet of the third heat exchanger through a delivery pipeline;

[0024] The heat medium outlet of the third heat exchanger is connected to the input end of the working medium pump through a delivery pipeline, and the output end of the working medium pump is connected to the refrigerant inlet of the first heat exchanger through a delivery pipeline;

[0025] The second power generation module is used to generate electricity using the heated working fluid;

[0026] The third heat exchanger is used to cool the working medium passing through the second power generation module;

[0027] The working medium pump is used to transport the cooled working medium to the first heat exchanger;

[0028] The first heat exchanger is used to heat the cooled working fluid using the heat of the geothermal medium, and to transport the heated working fluid to the second power generation module.

[0029] Preferably, the second power generation module includes: a second steam turbine and a second generator;

[0030] The input end of the second steam turbine is connected to the refrigerant outlet of the first heat exchanger through a delivery pipeline, and the output end of the second steam turbine is connected to the heat medium inlet of the third heat exchanger through a delivery pipeline; one end of the second steam turbine is connected to the second generator;

[0031] The second steam turbine is configured to rotate based on the heated working medium to drive the second generator to generate electricity.

[0032] Preferably, the system further comprises: an injection pump;

[0033] The input end of the injection pump is connected to the second heat exchanger, and the output end of the injection pump is connected to the hot dry rock reinjection well through a delivery pipeline; the injection pump pressurizes the cooled geothermal medium and reinjects it into the hot dry rock layer below the ground through the hot dry rock reinjection well.

[0034] Preferably, the heating device comprises: a heat collecting device, a heating return pipe and a heating water supply pipe;

[0035] The heat collecting device is connected to the refrigerant inlet of the third heat exchanger through the heating return pipe; the refrigerant outlet of the third heat exchanger is connected to the heating water supply pipe;

[0036] The heat collecting device is connected to the refrigerant inlet of the second heat exchanger through the heating return pipe; the refrigerant outlet of the second heat exchanger is connected to the heating water supply pipe;

[0037] The heat collecting device is connected to one end of the injection pump through the heating return pipe; the other end of the injection pump is connected to the heating water supply pipe;

[0038] The heat collection device is used to output the heat collection liquid. The heat collection liquid flows through the second heat exchanger through the heating return pipe to absorb the heat of the geothermal medium in the second heat exchanger, and flows through the third heat exchanger to absorb the heat of the working fluid in the third heat exchanger, and flows through the injection pump to absorb the heat generated when the injection pump pressurizes the geothermal medium, and provides heat through the heating water supply pipe.

[0039] Preferably, the heating device further comprises: a flow regulating valve;

[0040] A flow regulating valve is provided between the second heat exchanger, the third heat exchanger, the injection pump and the heating water supply pipe; the flow regulating valve is used to regulate the flow of the heat collecting liquid in the heating water supply pipe.

[0041] A second aspect of an embodiment of the present invention discloses a method for supplying electric heat based on high-temperature geothermal energy, which is applied to the electric heat supply system based on high-temperature geothermal energy disclosed in the first aspect of an embodiment of the present invention. The method includes:

[0042] Collecting geothermal media, wherein the geothermal media includes hydrothermal media or hot dry rock media;

[0043] generating electricity using the geothermal power generation device and the geothermal medium;

[0044] utilizing the heat of the geothermal medium to heat the working fluid in the dual-working fluid power generation device, and utilizing the heated working fluid to generate electricity;

[0045] utilizing the heat of the geothermal medium and the working fluid to heat the heat-collecting liquid in the heat supply device, and utilizing the heated heat-collecting liquid to provide heat;

[0046] The cooled geothermal medium is reinjected into the hot dry rock layer below the ground level through the hot dry rock reinjection well.

[0047] Preferably, the geothermal power generation device includes: a first power generation module and a gas-liquid separator; the input end of the gas-liquid separator is connected to the hot dry rock mining well via a delivery pipeline, and the first output end of the gas-liquid separator is connected to the input end of the first power generation module via a delivery pipeline; the second output end of the gas-liquid separator is connected to the output end of the first power generation module via a delivery pipeline, and the common end of the connection is connected to the heat medium inlet of the first heat exchanger; the use of the geothermal power generation device and the geothermal medium to generate electricity includes:

[0048] The gas-liquid separator is used to separate the geothermal medium into gas and liquid, and transport the separated high-temperature gas to the first power generation module, so that the first power generation module uses the high-temperature gas to generate electricity.

[0049] Based on the above-mentioned embodiments of the present invention, a high-temperature geothermal electric heat supply method and system is provided. The high-temperature geothermal electric heat supply system includes: a hot dry rock production well, a hot dry rock reinjection well, a geothermal power generation device, a dual-fluid power generation device, a heat supply device, a first heat exchanger, a second heat exchanger, and a third heat exchanger. The geothermal power generation device is connected to the hot dry rock production well, connected to the dual-fluid power generation device via the first heat exchanger, and connected to the heat supply device via the second heat exchanger. The dual-fluid power generation device is connected to the heat supply device via the third heat exchanger. The second heat exchanger is connected to the hot dry rock reinjection well. The geothermal power generation device generates electricity using geothermal medium. The dual-fluid power generation device absorbs heat from the geothermal medium through the first heat exchanger to generate electricity. The heat supply device absorbs heat from the working fluid and the geothermal medium through the second and third heat exchangers to provide heat. The cooled geothermal medium is reinjected into the hot dry rock layer below the ground through the hot dry rock reinjection well. This fully utilizes the heat resources of the geothermal medium, increases power generation, and improves resource utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] 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 merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0051] FIG1 is a first schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention;

[0052] FIG2 is a second schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention;

[0053] FIG3 is a third schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention;

[0054] FIG4 is a fourth schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention;

[0055] FIG5 is a fifth schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention;

[0056] FIG6 is a sixth schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention;

[0057] FIG7 is a flow chart of a method for supplying electric heat based on high-temperature geothermal energy according to an embodiment of the present invention. DETAILED DESCRIPTION

[0058] 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 creative efforts are within the scope of protection of the present invention.

[0059] In this application, the terms "comprises," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0060] As can be seen from the background technology, at present, only dry steam or dual working fluid is used for power generation, and the two power generation methods are not combined. The waste heat after power generation is discharged into the air through cooling and is not utilized, resulting in a waste of resources. The injection pump needs to provide a large pressure when pressurizing the geothermal medium and injecting it back into the dry hot rock formation. When the geothermal medium is a carbon dioxide circulating medium, the compression of carbon dioxide will release a large amount of heat energy, which is also not utilized. Therefore, at present, only one-level utilization of geothermal resources is carried out, and the heat of high-temperature geothermal resources is not fully utilized, which reduces the power generation and causes a waste of resources.

[0061] Therefore, an embodiment of the present invention provides a method and system for supplying high-temperature geothermal electricity. The system includes: a hot dry rock extraction well, a hot dry rock reinjection well, a geothermal power generation device, a dual-fluid power generation device, a heat supply device, a first heat exchanger, a second heat exchanger, and a third heat exchanger. The geothermal power generation device is connected to the hot dry rock extraction well, connected to the dual-fluid power generation device via the first heat exchanger, and connected to the heat supply device via the second heat exchanger. The dual-fluid power generation device is connected to the heat supply device via the third heat exchanger. The second heat exchanger is connected to the hot dry rock reinjection well. The geothermal power generation device generates electricity using geothermal medium. The dual-fluid power generation device absorbs heat from the geothermal medium through the first heat exchanger to generate electricity. The heat supply device absorbs heat from the working fluid and the geothermal medium through the second and third heat exchangers to supply heat. The cooled geothermal medium is reinjected into the hot dry rock layer below the ground through the hot dry rock reinjection well. This fully utilizes the heat resources of the geothermal medium, increases power generation, and improves resource utilization.

[0062] Referring to Figure 1, a first schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention is shown. The high-temperature geothermal-based electric heat supply system includes: a hot dry rock mining well 3, a hot dry rock reinjection well 4, a geothermal power generation device 001, a dual-fluid power generation device 002, a heat supply device 003, a first heat exchanger 10, a second heat exchanger 14 and a third heat exchanger 21.

[0063] 1 , a hot dry rock mining well 3 is set in a hot dry rock layer 1 below the ground level 5 ; wherein the hot dry rock layer is covered with many hot dry rock pressure fractures 2 , forming a fracture network.

[0064] It is understandable that the hot dry rock fractures 2 can be formed by pre-transforming the hot dry rock layer using the clean water large-scale fracturing technology, and the hot dry rock fractures 2 are used to improve the water conductivity of the hot dry rock layer 1.

[0065] Specifically, the hot dry rock mining well is connected to the input end of the geothermal power generation device 001 through a transmission pipeline 6; the output end of the geothermal power generation device 001 is connected to the first heat exchanger 10; the first heat exchanger 10 is connected to the second heat exchanger 14; the second heat exchanger 10 is connected to the hot dry rock reinjection well 4, and the hot dry rock reinjection well 4 is set in the hot dry rock layer 1 below the ground level 5; the dual-fluid power generation device 002 is connected to the first heat exchanger 10; the dual-fluid power generation device 002 is connected to the heat supply device 003 through the third heat exchanger 21; the heat supply device 003 is connected to the second heat exchanger 14.

[0066] It should be noted that the hot dry rock mining well 3 is used to collect geothermal media, wherein the geothermal media includes hydrothermal media or hot dry rock media; the hot dry rock media can be water or carbon dioxide.

[0067] The geothermal power generation device 001 is used to generate electricity using geothermal medium; the dual-fluid power generation device 002 is used to absorb the heat of the geothermal medium in the first heat exchanger 10, heat the working fluid (such as isobutane, n-butane, ammonia and other low-boiling-point media) in the dual-fluid power generation device 002, and use the heated working fluid to generate electricity; the heat supply device 003 is used to absorb the heat of the geothermal medium in the second heat exchanger 14 and the heat of the working fluid in the third heat exchanger 21, heat the heat collecting liquid in the heat supply device 003, and use the heated heat collecting liquid to provide heat; the hot dry rock reinjection well 4 is used to reinject the cooled geothermal medium into the hot dry rock layer 1 below the ground level 5.

[0068] In an embodiment of the present invention, a geothermal power generation device is connected to a hot dry rock extraction well, utilizing geothermal medium for primary power generation. Heat from the geothermal medium, which has undergone primary power generation, is then transferred via a first heat exchanger and a second heat exchanger to a dual-fluid power generation device and a heat supply device, enabling the dual-fluid power generation device to generate electricity using the heated working medium. Simultaneously, the heat from the working medium is transferred via a third heat exchanger to the heat supply device, which then utilizes the heated heat-collecting liquid for heat generation. This increases the number of power generation system stages, increases power generation, and improves the efficiency of geothermal medium power generation. The addition of a heat supply device fully utilizes waste heat after power generation, avoiding resource waste and maximizing geothermal resources.

[0069] 2 , which shows a second schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention, wherein the geothermal power generation device 001 includes a first power generation module 004 and a gas-liquid separator 7 .

[0070] Specifically, the input end of the gas-liquid separator 7 is connected to the hot dry rock mining well 3 through the conveying pipeline 6, and the first output end of the gas-liquid separator 7 is connected to the input end of the first power generation module 004 through the conveying pipeline 6; the second output end of the gas-liquid separator 7 and the output end of the first power generation module 004 are connected through the conveying pipeline 6, and the common end after connection is connected to the heat medium inlet of the first heat exchanger 10.

[0071] It can be understood that the heat exchanger includes a heat medium inlet, a heat medium outlet, a refrigerant inlet and a refrigerant outlet. Heat exchange is achieved through the heat exchanger, and the refrigerant is heated by the heat of the heat medium, while the heat of the refrigerant is cooled by the low temperature of the refrigerant.

[0072] It should be noted that the gas-liquid separator 7 is used to separate the geothermal medium into gas and liquid, and transport the separated high-temperature gas (or gas-liquid mixed medium, depending on the specific situation, not limited here) to the first power generation module 004, so that the first power generation module 004 uses the high-temperature gas to generate electricity. The high-temperature gas passing through the first steam turbine 8 is mixed with the liquid passing through the gas-liquid analyzer 7 and transported to the first heat exchanger 10 through the delivery pipeline 6.

[0073] In some embodiments, referring to FIG3 , a third schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention is shown, where the first power generation module 004 includes a first steam turbine 8 and a first generator 9 .

[0074] Specifically, the input end of the first steam turbine 8 is connected to the first output end of the gas-liquid separator 7 through the conveying pipeline 6, and the output end of the first steam turbine 8 is connected to the second output end of the gas-liquid separator 7 through the conveying pipeline 6; one end of the first steam turbine 8 is connected to the first generator 9.

[0075] It should be noted that the first steam turbine 8 is used to rotate based on the high-temperature gas separated by the gas-liquid separator 7 to drive the first generator 9 to generate electricity.

[0076] In an embodiment of the present invention, the geothermal medium is separated into gas and liquid by a gas-liquid separator, and the high-temperature gas obtained by separation is used to drive the first steam turbine to rotate, thereby driving the first generator to generate electricity.

[0077] 4 , which shows a fourth schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention, wherein the dual-fluid power generation device 002 includes a second power generation module 005 and a working fluid pump 13 .

[0078] Specifically, the input end of the second power generation module 005 is connected to the refrigerant outlet of the first heat exchanger 10 through the delivery pipe 6, and the output end of the second power generation module 005 is connected to the heat medium inlet of the third heat exchanger 21 through the delivery pipe 6; the heat medium outlet of the third heat exchanger 21 is connected to the input end of the working fluid pump 13 through the delivery pipe 6, and the output end of the working fluid pump 13 is connected to the refrigerant inlet of the first heat exchanger 10 through the delivery pipe 6.

[0079] It can be understood that the dual-fluid power generation device 002 uses working fluid to generate electricity, that is, the power generation resource in the corresponding transmission pipeline 6 of the dual-fluid power generation device 002 is working fluid (low-boiling point medium such as isobutane, n-butane, ammonia, etc.).

[0080] It should be noted that the second power generation module 005 is used to generate electricity using the heated working fluid; the third heat exchanger 21 is used to cool the working fluid passing through the second power generation module 005; the working fluid pump 13 is used to transport the cooled working fluid to the first heat exchanger 10; the first heat exchanger 10 is used to heat the cooled working fluid using the heat of the geothermal medium, and transport the heated working fluid to the second power generation module 005.

[0081] In some specific embodiments, referring to FIG5 , a fifth schematic diagram of a high-temperature geothermal-based electric heat supply system provided by an embodiment of the present invention is shown, where the second power generation module 005 includes a second steam turbine 11 and a second generator 12 .

[0082] Specifically, the input end of the second steam turbine 11 is connected to the refrigerant outlet of the first heat exchanger 10 through the delivery pipe 6, and the output end of the second steam turbine 11 is connected to the heat medium inlet of the third heat exchanger 21 through the delivery pipe 6; one end of the second steam turbine 11 is connected to the second generator 12.

[0083] It should be noted that the second steam turbine 11 is used to rotate based on the heated working medium to drive the second generator 12 to generate electricity.

[0084] That is, the geothermal medium passing through the geothermal power generation device 001 heats the working fluid in the dual-working fluid power generation device 002 through the first heat exchanger 10, vaporizing the working fluid, driving the second steam turbine 11 to rotate, and driving the second generator 12 to generate electricity; the working fluid after power generation is then cooled and liquefied through the third heat exchanger 21, and enters the working fluid pump 13 for pressurization, completing the entire cycle.

[0085] It can be understood that the working medium after power generation is cooled by the heat collecting liquid in the third heat exchanger 21 when passing through the third heat exchanger 21. Specifically, the heat collecting liquid absorbs the heat of the working medium. For an explanation of the heat collecting liquid, please refer to the content shown in Figure 6 below.

[0086] In the embodiment of the present invention, the heat of the geothermal medium is further utilized to heat the working fluid in the dual-working fluid power generation device to perform secondary power generation, thereby improving the utilization rate of the geothermal medium.

[0087] Referring to Figure 6, a sixth schematic diagram of an electric heat supply system based on high-temperature geothermal energy provided by an embodiment of the present invention is shown. The electric heat supply system based on high-temperature geothermal energy further includes: an injection pump 15; at the same time, the heating device 003 includes: a heat collection device, a heating return water pipe 16 and a heating water supply pipe 17.

[0088] Specifically, the input end of the injection pump 15 is connected to the second heat exchanger 14, and the output end of the injection pump 15 is connected to the hot dry rock reinjection well 4 through the delivery pipeline 6; the injection pump 15 pressurizes the cooled geothermal medium and injects it back into the hot dry rock layer 1 below the ground level 5 through the hot dry rock reinjection well 4.

[0089] It should be noted that the geothermal medium that has undergone two-stage power generation is cooled by the second heat exchanger 14 and transported to the injection pump 15 to be pressed into the underground heat reservoir for heating.

[0090] It is understood that injection pump 15 needs to provide a high pressure to pressurize the cooled geothermal medium into the deep geothermal reservoir. During the process of pressurizing the geothermal medium, injection pump 15 releases a large amount of heat. To maintain normal operating temperature of injection pump 15 and prevent overheating, a heat collection device is connected to one end of injection pump 15 via a heating return pipe 16. The other end of injection pump 15 is connected to a heating water supply pipe 17. The heat-collecting liquid in the heating return pipe 16 cools injection pump 15, while the heat-collecting liquid absorbs the heat from the injection pump 15 and is then transported to the heating water supply pipe.

[0091] Specifically, the thermal collecting equipment is connected to the refrigerant inlet of the third heat exchanger 21 through the heating return pipe 16; the refrigerant outlet of the third heat exchanger 21 is connected to the heating water supply pipe 17; the thermal collecting equipment is connected to the refrigerant inlet of the second heat exchanger 14 through the heating return pipe 16; the refrigerant outlet of the second heat exchanger 14 is connected to the heating water supply pipe 17; the thermal collecting equipment is connected to one end of the injection pump 15 through the heating return pipe 16; the other end of the injection pump 15 is connected to the heating water supply pipe 17.

[0092] It should be noted that the heat collection equipment is used to output heat collection liquid, which flows through the second heat exchanger 14 through the heating return pipe 16 to absorb the heat of the geothermal medium in the second heat exchanger 14, and flows through the third heat exchanger 21 to absorb the heat of the working fluid in the third heat exchanger 21, and flows through the injection pump 15 to absorb the heat generated when the injection pump 15 pressurizes the geothermal medium, and provides heat through the heating water supply pipe 17.

[0093] In some embodiments, the heating device further includes: a flow regulating valve (such as 18, 19 and 20 as shown in FIG6).

[0094] Specifically, flow regulating valves (such as 18 , 19 and 20 as shown in FIG6 ) are provided between the second heat exchanger 14 , the third heat exchanger 21 , the injection pump 15 and the heating water supply pipe 17 .

[0095] It should be noted that the flow regulating valves (such as 18, 19 and 20 shown in FIG6) are used to regulate the flow of the heat collecting liquid in the heating water supply pipe.

[0096] Specifically, the flow regulating valves (such as 18, 19 and 20 shown in FIG6 ) are used to adjust and control the temperature of each part to ensure the normal and reasonable operation of the high-temperature geothermal-based electric heat supply system provided by the embodiment of the present invention.

[0097] In the embodiment of the present invention, the geothermal power generation device, the dual-fluid power generation device and the heating device are combined to further improve the utilization efficiency of geothermal resources.

[0098] Corresponding to the high-temperature geothermal electric heat supply system provided in the above embodiment of the present invention, FIG7 shows a flow chart of a high-temperature geothermal electric heat supply method provided in the embodiment of the present invention. The high-temperature geothermal electric heat supply method includes:

[0099] Step S701: Collect geothermal medium.

[0100] In the specific implementation of step S701, a hot dry rock mining well disposed below the ground level is used to collect geothermal medium, wherein the geothermal medium includes a hydrothermal medium or a hot dry rock medium; the hot dry rock medium may be water or carbon dioxide.

[0101] Step S702: Generate electricity using a geothermal power generation device and geothermal medium.

[0102] It should be noted that the geothermal power generation device includes: a first power generation module and a gas-liquid separator; the input end of the gas-liquid separator is connected to the hot dry rock mining well through a transmission pipeline, and the first output end of the gas-liquid separator is connected to the input end of the first power generation module through a transmission pipeline; the second output end of the gas-liquid separator and the output end of the first power generation module are connected through a transmission pipeline, and the common end after connection is connected to the heat medium inlet of the first heat exchanger.

[0103] In the specific implementation of step S702, the gas-liquid separator is used to separate the geothermal medium into gas and liquid, and transport the separated high-temperature gas to the first power generation module, so that the first power generation module uses the high-temperature gas to generate electricity.

[0104] Step S703: using the heat of the geothermal medium to heat the working fluid in the dual-working fluid power generation device, and using the heated working fluid to generate electricity.

[0105] Step S704: using the heat of the geothermal medium and the working fluid to heat the heat collecting liquid in the heating device, and using the heated heat collecting liquid to provide heat.

[0106] Step S705: Reinject the cooled geothermal medium into the hot dry rock layer below the ground level through the hot dry rock reinjection well.

[0107] The specific implementation of steps S701 to S705 is shown in Figures 1 to 6 and will not be repeated here.

[0108] In the embodiment of the present invention, the geothermal power generation device, the dual-fluid power generation device and the heat supply device are combined to increase the number of power generation system stages, increase the power generation amount, and improve the power generation efficiency of the geothermal medium; the addition of the heat supply device fully utilizes the waste heat after power generation, avoids resource waste, and makes full use of geothermal resources.

[0109] In summary, embodiments of the present invention provide a method and system for supplying high-temperature geothermal electricity. The system includes: a hot dry rock extraction well, a hot dry rock reinjection well, a geothermal power generation device, a dual-fluid power generation device, a heat supply device, a first heat exchanger, a second heat exchanger, and a third heat exchanger. The geothermal power generation device is connected to the hot dry rock extraction well, connected to the dual-fluid power generation device via the first heat exchanger, and connected to the heat supply device via the second heat exchanger. The dual-fluid power generation device is connected to the heat supply device via the third heat exchanger. The second heat exchanger is connected to the hot dry rock reinjection well. The geothermal power generation device generates electricity using geothermal medium. The dual-fluid power generation device absorbs heat from the geothermal medium through the first heat exchanger to generate electricity. The heat supply device absorbs heat from the working fluid and the geothermal medium through the second and third heat exchangers to supply heat. The cooled geothermal medium is reinjected into the hot dry rock layer below the ground through the hot dry rock reinjection well. This fully utilizes the heat resources of the geothermal medium, increases power generation, and improves resource utilization.

[0110] Each embodiment in this specification is described in a progressive manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple. For relevant parts, refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without expending creative work.

[0111] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0112] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An electric heat supply system based on high temperature geothermal energy, characterized in that: The system comprises: a hot dry rock mining well, a hot dry rock reinjection well, a geothermal power generation device, a dual-fluid power generation device, a heat supply device, a first heat exchanger, a second heat exchanger and a third heat exchanger; The hot dry rock mining well is arranged in a hot dry rock layer below the ground level, and the hot dry rock mining well is connected to the input end of the geothermal power generation device through a transmission pipeline; the output end of the geothermal power generation device is connected to the first heat exchanger; The first heat exchanger is connected to the second heat exchanger; the second heat exchanger is connected to the hot dry rock reinjection well, and the hot dry rock reinjection well is set in the hot dry rock layer below the ground level; The dual-medium power generation device is connected to the first heat exchanger; the dual-medium power generation device is connected to the heat supply device through the third heat exchanger; the heat supply device is connected to the second heat exchanger; The hot dry rock mining well is used to collect geothermal medium, and the geothermal medium includes hydrothermal medium or hot dry rock medium; The geothermal power generation device is used to generate electricity using the geothermal medium; The dual-working fluid power generation device is used to absorb the heat of the geothermal medium in the first heat exchanger, heat the working fluid, and generate electricity using the heated working fluid; The heat supply device is used to absorb the heat of the geothermal medium in the second heat exchanger and the heat of the working fluid in the third heat exchanger, heat the heat collecting liquid, and use the heated heat collecting liquid to provide heat; The hot dry rock reinjection well is used to reinject the cooled geothermal medium into the hot dry rock layer below the ground level.

2. The system according to claim 1, characterized in that The geothermal power generation device comprises: a first power generation module and a gas-liquid separator; The input end of the gas-liquid separator is connected to the hot dry rock mining well through a delivery pipeline, and the first output end of the gas-liquid separator is connected to the input end of the first power generation module through a delivery pipeline; The second output end of the gas-liquid separator and the output end of the first power generation module are connected through a delivery pipeline, and the common end after the connection is connected to the heat medium inlet of the first heat exchanger; The gas-liquid separator is used to separate the geothermal medium into gas and liquid, and transport the separated high-temperature gas to the first power generation module, so that the first power generation module uses the high-temperature gas to generate electricity.

3. The system according to claim 2, characterized in that The first power generation module includes: a first steam turbine and a first generator; The input end of the first steam turbine is connected to the first output end of the gas-liquid separator through a delivery pipeline, and the output end of the first steam turbine is connected to the second output end of the gas-liquid separator through a delivery pipeline; one end of the first steam turbine is connected to the first generator; The first steam turbine is used to rotate based on the high-temperature gas to drive the first generator to generate electricity.

4. The system according to claim 1, characterized in that The dual-working fluid power generation device includes a second power generation module and a working fluid pump; The input end of the second power generation module is connected to the refrigerant outlet of the first heat exchanger through a delivery pipeline, and the output end of the second power generation module is connected to the heat medium inlet of the third heat exchanger through a delivery pipeline; The heat medium outlet of the third heat exchanger is connected to the input end of the working fluid pump through a delivery pipeline, and the output end of the working fluid pump is connected to the refrigerant inlet of the first heat exchanger through a delivery pipeline; The second power generation module is used to generate electricity using the heated working fluid; The third heat exchanger is used to cool the working medium passing through the second power generation module; The working fluid pump is used to transport the cooled working fluid to the first heat exchanger; The first heat exchanger is used to heat the cooled working fluid using the heat of the geothermal medium, and transport the heated working fluid to the second power generation module.

5. The system according to claim 4, characterized in that The second power generation module includes: a second steam turbine and a second generator; The input end of the second steam turbine is connected to the refrigerant outlet of the first heat exchanger through a delivery pipeline, and the output end of the second steam turbine is connected to the heat medium inlet of the third heat exchanger through a delivery pipeline; one end of the second steam turbine is connected to the second generator; The second steam turbine is used to rotate based on the heated working medium to drive the second generator to generate electricity.

6. The system according to claim 1, characterized in that The system also includes: an injection pump; The input end of the injection pump is connected to the second heat exchanger, and the output end of the injection pump is connected to the hot dry rock reinjection well through a delivery pipeline; the injection pump pressurizes the cooled geothermal medium and injects it back into the hot dry rock layer below the ground through the hot dry rock reinjection well.

7. The system according to claim 6, characterized in that The heating device comprises: a heat collecting device, a heating return pipe and a heating water supply pipe; The heat collecting device is connected to the refrigerant inlet of the third heat exchanger through the heating water return pipe; the refrigerant outlet of the third heat exchanger is connected to the heating water supply pipe; The heat collecting device is connected to the refrigerant inlet of the second heat exchanger through the heating water return pipe; the refrigerant outlet of the second heat exchanger is connected to the heating water supply pipe; The heat collecting device is connected to one end of the injection pump through the heating return water pipe; the other end of the injection pump is connected to the heating water supply pipe; The heat collecting device is used to output the heat collecting liquid, and the heat collecting liquid flows through the second heat exchanger through the heating return water pipe to absorb the heat of the geothermal medium in the second heat exchanger, flows through the third heat exchanger to absorb the heat of the working fluid in the third heat exchanger, and flows through the injection pump to absorb the heat generated when the injection pump pressurizes the geothermal medium, and provides heat through the heating water supply pipe.

8. The system according to claim 7, characterized in that The heating device further comprises: a flow regulating valve; A flow regulating valve is provided between the second heat exchanger, the third heat exchanger, the injection pump and the heating water supply pipe; the flow regulating valve is used to regulate the flow of the heat collecting liquid in the heating water supply pipe.

9. A method for supplying electric heat based on high-temperature geothermal energy, characterized in that: Applied to the high-temperature geothermal electric heat supply system according to any one of claims 1 to 8, the method comprises: Collecting geothermal medium, wherein the geothermal medium includes hydrothermal medium or hot dry rock medium; Generating electricity using the geothermal power generation device and the geothermal medium; Using the heat of the geothermal medium to heat the working fluid in the dual-working fluid power generation device, and using the heated working fluid to generate electricity; Using the heat of the geothermal medium and the working fluid to heat the heat collecting liquid in the heat supply device, and using the heated heat collecting liquid to provide heat; The cooled geothermal medium is reinjected into the hot dry rock layer below the ground level through the hot dry rock reinjection well.

10. The method according to claim 9, characterized in that The geothermal power generation device comprises: a first power generation module and a gas-liquid separator; the input end of the gas-liquid separator is connected to the hot dry rock mining well through a delivery pipeline, and the first output end of the gas-liquid separator is connected to the input end of the first power generation module through a delivery pipeline; the second output end of the gas-liquid separator and the output end of the first power generation module are connected through a delivery pipeline, and the common end after connection is connected to the heat medium inlet of the first heat exchanger; the use of the geothermal power generation device and the geothermal medium to generate electricity comprises: The gas-liquid separator is used to separate the geothermal medium into gas and liquid, and transport the separated high-temperature gas to the first power generation module, so that the first power generation module uses the high-temperature gas to generate electricity.

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