Supercritical carbon dioxide cycle power generation system and method coupled with shale gas exploitation

Abstract

The invention discloses a supercritical carbon dioxide cycle power generation system and method coupled with shale gas exploitation. The system is mainly composed of a cycle power generation module and a shale gas exploitation module. The circulating power generation module comprises a main compressor, a low-temperature heat regenerator, a high-temperature heat regenerator, a heat source, a turbine, a re-compressor, a power generator and other key components. Supercritical carbon dioxide generated by the shale gas exploitation module enters the circulating power generation module through a main compressor, and finally drives a power generator to generate power through the processes of compression, heating, expansion acting and the like. And meanwhile, part of the acting fluid flows back to the re-compressor to be re-compressed, and part of the acting fluid returns to the shale layer to be injected, so that closed-loop circulation is formed. According to the system, efficient coupling of shale gas exploitation and supercritical carbon dioxide cycle power generation is achieved, supercritical carbon dioxide generated by shale gas exploitation is converted to serve as a working medium of a power system, and full utilization of energy is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy mining and power generation, and relates to a supercritical carbon dioxide circulation power generation system and method coupled with shale gas mining. Background Art

[0002] Under the dual pressures of global energy structure transformation and environmental protection, traditional thermal power generation has high energy consumption and significant carbon emission characteristics. In this context, it is urgent to explore and utilize clean and efficient energy alternatives. Shale gas, as a rich unconventional natural gas resource, is regarded as an important part of future energy supply due to its large reserves and huge mining potential. Compared with coal power generation, shale gas power generation has significant advantages in environmental protection, high efficiency and sustainability, and can effectively reduce greenhouse gas emissions and promote the optimization and upgrading of energy structure.

[0003] However, effective shale gas extraction faces multiple challenges, especially the increasingly prominent environmental problems caused by traditional hydraulic fracturing technology. This technology not only consumes a huge amount of water, which puts pressure on water resources, but also has limited effect on increasing production. More importantly, it may cause irreversible impacts on geological structures, such as inducing earthquakes and contaminating groundwater.

[0004] Supercritical carbon dioxide fracturing technology uses carbon dioxide instead of water as the working fluid, which can effectively reduce greenhouse gas emissions. Its low viscosity, super fluidity, permeability and adsorption capacity show great potential in the fields of energy conversion and fluid extraction, and has become an important technical direction for shale gas resource exploitation.

[0005] However, the supercritical carbon dioxide produced in existing shale gas extraction has not been fully utilized, which not only causes energy waste but also causes certain pollution to the environment. Summary of the invention

[0006] The purpose of the present invention is to solve the technical problem that supercritical carbon dioxide produced by shale gas extraction in the prior art has not been fully utilized, and to provide a supercritical carbon dioxide circulation power generation system and method coupled with shale gas extraction.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions: A first aspect of the present invention provides a supercritical carbon dioxide cycle power generation system coupled with shale gas extraction, comprising a cycle power generation module and a shale gas extraction module; The cycle power generation module comprises a main compressor, a low-temperature regenerator, a high-temperature regenerator, a heat source, a turbine, a recompressor and a generator; The outlet of the main compressor is connected to the inlet of the cold side of the low-temperature regenerator, the outlet of the cold side of the low-temperature regenerator is connected to the heat source via the cold side of the high-temperature regenerator, the outlet of the heat source is connected to the inlet of the turbine, the outlet of the turbine passes through the hot side of the high-temperature regenerator and the hot side of the low-temperature regenerator in turn to form a shunt pipeline, which is respectively connected to the shale layer injection well pipe and the inlet of the recompressor; the outlet of the recompressor is connected to the pipeline before the inlet of the cold side of the high-temperature regenerator; the main compressor, the recompressor and the turbine are all connected to the generator; The shale gas production module is connected to the main compressor, and the supercritical carbon dioxide produced by the shale gas production module enters the circulation power generation module through the inlet of the main compressor to achieve the recycling of carbon dioxide.

[0008] Furthermore, the shale gas extraction module includes a solid separator, a gas-liquid separator, a compressor, a storage tank and a heater; the shale layer oil and gas well pipe outlet is connected to the solid separator inlet; the solid separator outlet is connected to the gas-liquid separator inlet; the gas-liquid separator outlet is connected to the compressor inlet, the compressor outlet is connected to the heater, and the heater outlet is connected to the main compressor inlet to form a supercritical carbon dioxide circulation loop.

[0009] Furthermore, the output end of the generator is electrically connected to the compressor, booster pump and heater of the shale gas extraction module respectively to achieve self-supply of energy.

[0010] Furthermore, a storage tank is connected between the compressor outlet and the heater.

[0011] Furthermore, a booster pump is connected between the storage tank outlet and the heater.

[0012] Furthermore, a buffer tank is connected between the heater outlet and the main compressor.

[0013] Furthermore, the buffer tank is provided with a pressure balancing device.

[0014] Furthermore, the main compressor, re-compressor and turbine are coaxially connected to the generator to achieve coaxial power output of the three machines.

[0015] Furthermore, the heat source is an external heat source, which is used to provide heat for the supercritical carbon dioxide to reach a high temperature state.

[0016] A second aspect of the present invention provides a supercritical carbon dioxide cycle power generation method coupled with shale gas extraction, comprising the following steps: The supercritical carbon dioxide produced by shale gas extraction is heated and fed into a compressor to generate high-pressure, low-temperature fluid; The high-pressure low-temperature fluid is input into the cold side of the low-temperature regenerator, and the working fluid flowing out of the low-temperature regenerator is combined with the working fluid flowing out of the recompressor and then passes through the high-temperature regenerator and the heat source to generate a high-pressure high-temperature fluid; The high-pressure and high-temperature fluid expands through the turbine and drives the turbine to rotate and do work, driving the engine to generate electricity; The low-pressure and high-temperature fluid after doing work enters the hot side of the high-temperature regenerator and the hot side of the low-temperature regenerator in turn to release heat, and is divided into two streams at the hot side outlet of the low-temperature regenerator, one enters the shale layer and is injected into the well pipe, and the other enters the re-compressor to do work.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a supercritical carbon dioxide cycle power generation system coupled with shale gas exploitation. The system uses supercritical carbon dioxide as a working medium, and utilizes its excellent thermophysical properties in a supercritical state, such as high density, low viscosity and good heat transfer performance, to significantly improve thermal efficiency. After absorbing heat in a heat source, supercritical carbon dioxide expands and performs work, driving the turbine to rotate, and then driving the generator to generate electricity. The energy conversion efficiency of the entire cycle process is high, and the energy utilization rate is effectively improved. The high-temperature regenerator and the low-temperature regenerator provided in the system realize the full recovery and reuse of the waste heat of carbon dioxide at the turbine outlet. The low-temperature regenerator preheats the carbon dioxide entering the system, and the high-temperature regenerator further increases the temperature of the recompressed carbon dioxide, reduces the input power of the external heat source, and enhances the overall thermal efficiency of the system. The system directly uses the supercritical carbon dioxide generated in the shale gas exploitation process as a medium for cycle power generation, which not only solves the problem of waste treatment in shale gas exploitation, but also realizes the maximum utilization of resources. By injecting supercritical carbon dioxide into the shale layer, it not only helps the effective exploitation of shale gas, but also reduces greenhouse gas emissions to a certain extent, and promotes green and low-carbon development. The setting of the recompressor allows part of the carbon dioxide to be compressed again after work and re-enter the high-temperature regenerator for preheating, which increases the flexibility and stability of the system. At the same time, the main compressor, recompressor and turbine are all connected to the generator, ensuring stable power supply under different working conditions and improving the overall reliability of the system.

[0018] Furthermore, by integrating the shale gas mining module with the supercritical carbon dioxide cycle power generation module, the maximum utilization of resources is achieved. The waste (supercritical carbon dioxide) in the shale gas mining process is used as the working medium of the power generation module to generate electricity without additional treatment, which reduces the greenhouse gas emissions after the original shale gas mining, and is in line with the green and low-carbon energy development trend. The shale gas mining module includes a solid separator, a gas-liquid separator, a compressor, a storage tank, a booster pump and a heater. The functions of each component are clear and easy to maintain and replace. This modular design improves the reliability and flexibility of the system. The power output by the generator is directly supplied to the compressor, booster pump and heater in the shale gas mining module, achieving energy self-sufficiency, reducing external power dependence and reducing operating costs. The storage tank connected between the compressor outlet and the heater is used to store liquid carbon dioxide, ensuring the stable operation of the system during non-continuous mining or fluctuations in power generation demand. The booster pump further increases the pressure of the liquid carbon dioxide to ensure that it smoothly enters the heater and is heated to a supercritical state. The buffer tank connected between the heater outlet and the main compressor plays a role in stabilizing and buffering, avoiding the impact of system pressure fluctuations on the main compressor. At the same time, the pressure balancing device installed in the buffer tank further ensures the safe operation of the system.

[0019] Furthermore, the design of the coaxial connection reduces the loss of energy during the transmission process. In traditional designs, the various components may be connected through gear boxes or transmission belts, which introduce additional friction and energy loss. The coaxial connection transmits power directly through the shaft, reducing the intermediate links in energy transmission and improving the overall energy conversion efficiency of the system. The design of the coaxial connection allows the system to flexibly adjust the operating status of each component according to actual needs. For example, when the power generation needs to be increased, the output power of the generator can be increased by adjusting the speed of the turbine; when the energy consumption of the system needs to be reduced, it can be achieved by adjusting the operating status of the main compressor and the re-compressor.

[0020] Furthermore, the external heat source provides stable and sufficient heat for the supercritical carbon dioxide, enabling it to quickly reach a high temperature and high pressure state. This efficient heat energy conversion process ensures that the supercritical carbon dioxide can efficiently perform work in the circulating power generation module, thereby improving the energy conversion efficiency of the entire system.

[0021] Furthermore, the present invention provides a supercritical carbon dioxide cycle power generation method coupled with shale gas exploitation, which uses supercritical carbon dioxide generated in the shale gas exploitation process as a working medium, and realizes efficient use of energy through multiple links such as heating, compression, heat recovery, and expansion work. Supercritical carbon dioxide always maintains efficient thermophysical properties, such as high density and low viscosity, during the cycle, thereby improving the energy conversion efficiency of the entire system. By recycling the waste (supercritical carbon dioxide) generated by shale gas exploitation as the working medium of the supercritical carbon dioxide cycle, greenhouse gas emissions and environmental pollution in the original shale gas exploitation are reduced. The electric energy generated by the supercritical carbon dioxide cycle is used to power the equipment in the shale gas exploitation module, thereby improving the energy utilization efficiency. The waste heat generated by the power generation module is recycled by the shale gas exploitation module, thereby reducing the amount of heat discharged to the outside by the overall system and improving the energy conversion efficiency of the system. At the same time, the method also uses a high-temperature regenerator and a low-temperature regenerator to reheat the working fluid, thereby reducing energy loss and further improving the energy efficiency and environmental performance of the system. The cycle flow in the method is reasonably designed, and the links are closely connected to ensure the stability and reliability of the system. In particular, the setting of the re-compressor allows part of the working fluid to re-enter the cycle after work, increasing the flexibility and adaptability of the system and maintaining stable power output under different working conditions. This method not only realizes the effective exploitation of shale gas, but also makes full use of the supercritical carbon dioxide generated during the exploitation process, converting it into electricity, and realizing the maximum utilization of resources. This not only improves the economic value of resources, but also promotes the development of clean energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 This is a diagram of the supercritical carbon dioxide cycle power generation system coupled with shale gas extraction in the present invention.

[0024] Among them: 1-1, buffer tank; 1-2, compressor; 1-3, re-compressor; 1-4, low-temperature regenerator; 1-5, high-temperature regenerator; 1-6, heat source; 1-7, turbine; 1-8, generator; 2-1, solid separator; 2-2, gas-liquid separator; 2-3, compressor; 2-4, storage tank; 2-5, booster pump; 2-6, heater. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and marked in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0029] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] The present invention is further described in detail below in conjunction with the accompanying drawings: See also Figure 1, the present invention provides a supercritical carbon dioxide cycle power generation system coupled with shale gas extraction, including a cycle power generation module and a shale gas extraction module; The cycle power generation module comprises a main compressor 1-2, a low temperature regenerator 1-4, a high temperature regenerator 1-5, a heat source 1-6, a turbine 1-7, a recompressor 1-3 and a generator 1-8; The outlet of the main compressor 1-2 is connected to the cold side inlet of the low-temperature regenerator 1-4, the cold side outlet of the low-temperature regenerator 1-4 is connected to the heat source 1-6 via the cold side of the high-temperature regenerator 1-5, the outlet of the heat source 1-6 is connected to the inlet of the turbine 1-7, the outlet of the turbine 1-7 passes through the hot side of the high-temperature regenerator 1-5 and the hot side of the low-temperature regenerator 1-4 in turn to form a diversion pipeline, which is respectively connected to the shale layer injection well pipe and the inlet of the recompressor 1-3; the outlet of the recompressor 1-3 is connected to the pipeline before the cold side inlet of the high-temperature regenerator 1-5; the main compressor 1-2, the recompressor 1-3 and the turbine 1-7 are all connected to the generator 1-8 and are coaxially connected; the heat source 1-6 is an external heat source, which is used to provide heat for the supercritical carbon dioxide to reach a high temperature state.

[0032] The shale gas extraction module includes a solid separator 2-1, a gas-liquid separator 2-2, a compressor 2-3 and a heater 2-6; the outlet of the shale layer oil and gas well pipe is connected to the inlet of the solid separator 2-1; the outlet of the solid separator 2-1 is connected to the inlet of the gas-liquid separator 2-2; the outlet of the gas-liquid separator 2-2 is connected to the inlet of the compressor 2-3, the outlet of the compressor 2-3 is connected to the heater 2-6, and a storage tank 2-4 is connected between the outlet of the compressor 2-3 and the heater 2-6. A booster pump 2-5 is connected between the outlet of the storage tank 2-4 and the heater 2-6. The outlet of the heater 2-6 is connected to the buffer tank 1-1. The outlet of the buffer tank 1-1 is connected to the inlet of the main compressor 1-2 to form a supercritical carbon dioxide circulation loop. The buffer tank 1-1 is provided with a pressure balancing device.

[0033] The output ends of the generator 1-8 are respectively connected to the compressor 2-3, the booster pump 2-5 and the heater 2-6 of the shale gas extraction module to achieve self-supply of energy.

[0034] The working process / working principle of the present invention is as follows: Low-pressure and low-temperature supercritical carbon dioxide enters the main compressor 1-2 from the buffer tank 1-1; the compressed fluid enters the cold side of the low-temperature regenerator 1-4 to absorb heat, and then merges with the fluid at the outlet of the recompressor 1-3. The merged fluid is heated to a high-temperature and high-pressure state through the cold side of the high-temperature regenerator 1-5 and the heat source 1-6 in turn. The high-temperature and high-pressure fluid enters the turbine 1-7 to expand and do work, driving the generator 1-8 to generate electricity. The fluid that has done work releases heat in turn on the hot side of the high-temperature regenerator 1-5 and the hot side of the low-temperature regenerator 1-4, part of which returns to the recompressor 1-3, and part of which is injected into the shale layer.

[0035] The supercritical carbon dioxide cycle power generation system coupled with shale gas exploitation of the present invention adopts supercritical carbon dioxide as the working medium, and its unique physical properties (such as high density and low viscosity) significantly improve the fracturing effect. The main compressor, recompressor and turbine in the cycle power generation module are coaxially connected with the generator, which reduces the loss in the energy transfer process and improves the energy efficiency of the overall system. The supercritical carbon dioxide generated in the shale gas exploitation process is used as the power generation medium, which significantly reduces greenhouse gas emissions. The electric energy produced by supercritical carbon dioxide can be fully utilized as the equipment self-use electricity of the shale gas exploitation module, further reducing energy consumption. The shale gas exploitation module is tightly coupled with the cycle power generation module to maximize the utilization of resources. The supercritical carbon dioxide generated during the exploitation process directly enters the cycle power generation module without additional processing. The storage tanks, booster pumps and buffer tanks in the system are reasonably designed to ensure the stable supply and efficient utilization of supercritical carbon dioxide. The power output by the generator not only meets the energy demand of the system itself, but also can be used to supply power to the outside, increasing the income source of the system.

[0036] The present invention discloses a supercritical carbon dioxide cycle power generation method coupled with shale gas extraction, specifically: Low-pressure and low-temperature supercritical carbon dioxide enters compressor 1-2 and is compressed into high-pressure and low-temperature fluid, and then enters the cold side of low-temperature regenerator 1-4 to absorb heat. After merging with the working fluid from the outlet of re-compressor 1-3 at the outlet of the cold side of low-temperature regenerator 1-4, the merged working fluid enters the cold side of high-temperature regenerator 1-5 and the heat exchange flow channel of heat source 1-6 in turn to absorb heat and become high-temperature and high-pressure fluid, and then enters turbine 1-7 to expand rapidly and drive turbine 1-7 to rotate. The low-pressure and high-temperature fluid after doing work enters the hot side of high-temperature regenerator 1-5 and the hot side of low-temperature regenerator 1-4 in turn to release heat, and is divided into two fluids at the outlet of the hot side of low-temperature regenerator 1-4, one part enters the shale layer injection well pipe, and the other part enters the re-compressor 1-3.

[0037] Supercritical carbon dioxide is injected into the shale layer to diffuse and generate pressure, causing cracks in the shale layer to expand. Shale gas flows to the production well through the crack network and is collected through the oil and gas well pipe. The gasified carbon dioxide and shale gas carry rock fragment particles out of the oil and gas well pipe and enter the solid separator 2-1 for solid deposition, and then enter the gas-liquid separator 2-2 for separation of carbon dioxide and shale gas. The separated gaseous carbon dioxide is compressed into liquid by the compressor 2-3 and then enters the storage tank 2-4 for storage. The liquid carbon dioxide in the storage tank 2-4 is pressurized by the booster pump 2-5 and heated by the heater 2-6, and then enters the buffer tank 1-1 for pressure stabilization, and then enters the main compressor 1-2.

[0038] The present invention first sends the supercritical carbon dioxide working fluid flowing out of the heater 2-6 in the shale gas extraction module to the circulation power generation module, and then injects it into the shale layer for fracturing, so that the carbon dioxide can be used to achieve the conversion of thermal energy into electrical energy. The electrical energy provided by the power generation module can power the compressor 2-3, the booster pump 2-5 and the heater 2-6 in the shale gas extraction module, saving electricity costs. The supercritical carbon dioxide working fluid flowing out of the hot side of the low-temperature regenerator 1-4 in the circulation power generation module is sent to the shale layer for fracturing, which can realize the reuse of the waste heat discharged from the power generation module.

[0039] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A supercritical carbon dioxide cycle power generation system coupled with shale gas extraction, characterized in that: Including cycle power generation module and shale gas extraction module; The cycle power generation module comprises a main compressor (1-2), a low-temperature regenerator (1-4), a high-temperature regenerator (1-5), a heat source (1-6), a turbine (1-7), a recompressor (1-3) and a generator (1-8); The outlet of the main compressor (1-2) is connected to the cold side inlet of the low-temperature regenerator (1-4), the cold side outlet of the low-temperature regenerator (1-4) is connected to the heat source (1-6) via the cold side of the high-temperature regenerator (1-5), the outlet of the heat source (1-6) is connected to the inlet of the turbine (1-7), the outlet of the turbine (1-7) passes through the hot side of the high-temperature regenerator (1-5) and the hot side of the low-temperature regenerator (1-4) in sequence to form a branch pipeline, which is respectively connected to the shale layer injection well pipe and the inlet of the recompressor (1-3); the outlet of the recompressor (1-3) is connected to the pipeline before the cold side inlet of the high-temperature regenerator (1-5); the main compressor (1-2), the recompressor (1-3) and the turbine (1-7) are all connected to the generator (1-8); The shale gas extraction module is connected to the main compressor (1-2), and the supercritical carbon dioxide generated by the shale gas extraction module enters the circulation power generation module through the inlet of the main compressor (1-2), thereby realizing the recycling and utilization of the carbon dioxide.

2. The supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to claim 1 is characterized in that: The shale gas extraction module comprises a solid separator (2-1), a gas-liquid separator (2-2), a compressor (2-3) and a heater (2-6); the outlet of the shale layer oil and gas well pipe is connected to the inlet of the solid separator (2-1); the outlet of the solid separator (2-1) is connected to the inlet of the gas-liquid separator (2-2); the outlet of the gas-liquid separator (2-2) is connected to the inlet of the compressor (2-3), the outlet of the compressor (2-3) is connected to the heater (2-6), and the outlet of the heater (2-6) is connected to the inlet of the main compressor (1-2) to form a supercritical carbon dioxide circulation loop.

3. The supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to claim 2 is characterized in that: The output end of the generator (1-8) is respectively connected to the compressor (2-3), the booster pump (2-5) and the heater (2-6) of the shale gas extraction module, thereby achieving self-supply of energy.

4. The supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to claim 2 is characterized in that: A storage tank (2-4) is connected between the compressor (2-3) outlet and the heater (2-6).

5. The supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to claim 4 is characterized in that: A booster pump (2-5) is connected between the outlet of the storage tank (2-4) and the heater (2-6).

6. The supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to claim 2 is characterized in that: A buffer tank (1-1) is connected between the outlet of the heater (2-6) and the main compressor (1-2).

7. The supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to claim 6, characterized in that: The buffer tank (1-1) is provided with a pressure balancing device.

8. The supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to claim 1, characterized in that: The main compressor (1-2), the re-compressor (1-3) and the turbine (1-7) are coaxially connected with the generator (1-8) to achieve coaxial power output of the three machines.

9. The supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to claim 1, characterized in that: The heat source (1-6) is an external heat source, which is used to provide heat for the supercritical carbon dioxide to reach a high temperature state.

10. A supercritical carbon dioxide cycle power generation method coupled with shale gas extraction, based on the supercritical carbon dioxide cycle power generation system coupled with shale gas extraction according to any one of claims 1 to 9, characterized in that: The following steps are involved: The supercritical carbon dioxide produced by shale gas extraction is heated and input into a compressor (1-2) to generate a high-pressure and low-temperature fluid; Inputting a high-pressure low-temperature fluid into the cold side of a low-temperature regenerator (1-4), combining the working fluid flowing out of the low-temperature regenerator (1-4) with the working fluid flowing out of the recompressor (1-3), and passing through a high-temperature regenerator (1-5) and a heat source (1-6) to generate a high-pressure high-temperature fluid; The high-pressure and high-temperature fluid expands through the turbine (1-7) and drives the turbine (1-7) to rotate and perform work, thereby driving the engine (1-8) to generate electricity; After doing work, the low-pressure and high-temperature fluid enters the hot side of the high-temperature regenerator (1-5) and the hot side of the low-temperature regenerator (1-4) in turn to release heat, and is divided into two streams of fluid at the hot side outlet of the low-temperature regenerator (1-4), one of which enters the shale layer and is injected into the well pipe, and the other enters the re-compressor (1-3) to do work.

Images