Waste oil and gas well carbon sequestration and energy storage peak shaving system based on industrial flue gas

Abstract

The invention belongs to the field of energy management, relates to an electric power peak regulation technology, and aims to solve the problem that fluctuating renewable energy cannot be efficiently absorbed and utilized to reduce the peak regulation burden of an electric power system in the prior art, in particular to a waste oil and gas well carbon sequestration and energy storage peak regulation system based on industrial flue gas. Comprising a flue gas injection subsystem, a deep ground carbon sequestration and energy storage combined subsystem and a geothermal enhanced compressed flue gas power generation subsystem, the flue gas injection subsystem comprises a compression device, an inlet of the compression device is communicated with a factory exhaust flue gas outlet, and the compression device is connected with a heat recovery device for heat exchange; through cooperative work of the three subsystems, the high-energy-consumption separation process of carbon dioxide enrichment in flue gas is canceled, geothermal resources are spontaneously utilized, the abandoned stratum serves as a medium for photovoltaic wind power energy storage and spontaneous carbon sequestration, and redundant photovoltaic wind power waiting energy storage is converted into compressed flue gas potential energy.

Description

Technical Field

[0001] The present invention belongs to the field of energy management and relates to power peak-shaving technology, specifically to an abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas. Background Art

[0002] With the increasing pressure of climate change and the accelerated advancement of energy transformation, reducing greenhouse gas emissions and improving the efficiency of renewable energy utilization have become the common goals of all countries. Due to the long-term development of oil and gas resources around the world, many abandoned oil and gas wells have been generated and accumulated. These wellheads are deep, widely distributed and highly closed. Research in recent years has shown that these abandoned oil and gas wells can not only be used for underground carbon storage, but also provide resource support for geothermal energy development. Especially in geothermal reserves and low-carbon energy systems, abandoned oil and gas wells have sufficient reuse value. According to foreign research, the cost of using abandoned oil and gas wells as carbon dioxide storage facilities is far less than that of building new underground storage facilities. Considering that renewable energy generation methods such as photovoltaic and wind power are heavily dependent on weather conditions, their output power is unstable and intermittent, causing fluctuations in the grid burden and increasing the peak-shaving and absorption pressure on the grid.

[0003] Therefore, how to efficiently absorb and utilize fluctuating renewable energy to reduce the peak-shaving burden of the power system is one of the problems that current energy technology urgently needs to solve. In this context, this patent proposes the use of new or abandoned oil and gas wells to couple deep carbon sequestration and geothermal enhanced compressed flue gas energy storage and peak-shaving systems, taking into account the needs of long-term and permanent geological carbon sequestration, geothermal utilization and long-term energy storage and peak-shaving, and has good application prospects and significance. Summary of the invention

[0004] The purpose of the present invention is to provide an abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas, which is used to solve the problem that the existing technology cannot efficiently absorb and utilize fluctuating renewable energy to reduce the peak-shaving burden of the power system.

[0005] The technical problem to be solved by the present invention is: how to provide an abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas that can efficiently absorb and utilize fluctuating renewable energy to reduce the peak-shaving burden of the power system.

[0006] The object of the present invention can be achieved by the following technical solutions: an abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas, including a flue gas injection subsystem, a deep-earth carbon sequestration and energy storage combined subsystem and a geothermally enhanced compressed flue gas power generation subsystem; The flue gas injection subsystem includes a compression device, the inlet of the compression device is connected to the factory exhaust flue gas outlet, the compression device is connected to the heat recovery device for heat exchange, the compression device is provided with kinetic energy by a motor, and the motor is powered by photovoltaic wind power; Furthermore, the first automatic control valve executes the signal sent by the centralized computing controller, adjusts the valve opening according to the size of the fluctuating green electricity, and ensures that the compressed flue gas is sent to the abandoned oil and gas well or the new well; The deep ground coupled carbon sequestration and geothermal enhanced compressed flue gas energy storage subsystem includes a casing, a groundwater injection pipeline is arranged in the multiple layers of well completion in the casing, one inlet of the casing is connected to the compressed flue gas outlet of the compression device, one outlet of the casing is connected to the pores of the abandoned oil and gas well formation, the inlet of the groundwater injection pipeline is connected to the cooling water outlet of the heat exchanger, the outlet of the groundwater injection pipeline is connected to the groundwater liquid level in the casing, an automatic control valve and a flow meter are arranged at the inlet of the groundwater injection pipeline, and a water pump is arranged on the groundwater injection pipeline; The geothermal enhanced compressed flue gas power generation subsystem includes a multi-stage turbine, the inlet of the multi-stage turbine is connected to the compressed high-temperature flue gas outlet of the wellhead of a new well or an abandoned oil and gas well, the outlet of the multi-stage turbine is connected to the outside atmosphere, the multi-stage turbine exchanges heat with a heat exchanger, the inlet of the heat exchanger is connected to the circulating steam outlet of a heat recovery device on one path, and is connected to the underground hot water outlet of a groundwater injection pipeline on the other path, the outlet of the heat exchanger is connected to the circulating water inlet of the heat recovery device on one path, and is connected to the cooling water inlet of the groundwater injection pipeline on the other path, and the multi-stage turbine is used to drive the generator to generate electricity and supply the power grid; Furthermore, the second automatic control valve and the third automatic control valve execute the signal sent by the centralized computing controller, and adjust the flow of underground compressed decarbonized flue gas entering the multi-stage turbine and the flow of geothermal brine entering the heat exchanger according to the peak and valley power shortage demand of the power grid, so as to meet the process index requirements of the multi-stage turbine power generation power grid and the expansion work temperature.

[0007] A further improvement of the present invention is that the compression device is driven by a motor, and the motor is turned on or off in coordination with the fluctuation of photovoltaic wind power or other power to be adjusted, so as to achieve minute-level response and compress industrial flue gas for energy storage.

[0008] A further improvement of the present invention is that the high-temperature compressed flue gas at the outlet of the compression device is passed into a heat recovery device, and the recovered heat is used to heat the working medium in the multi-stage turbine or external steam.

[0009] A further improvement of the present invention is that the geothermally enhanced compressed flue gas power generation subsystem uses compressed factory flue gas as a working fluid.

[0010] A further improvement of the present invention is that when the system has green electricity or other electricity to be adjusted, the first automatic control valve is opened, and the second control valve and the third control valve are closed. At this time, the motor driven by photovoltaic wind power or other electricity to be adjusted provides power to the compression device to compress the flue gas collected from the factory, and the outlet high-temperature and high-pressure flue gas is heat-exchanged through a heat recovery device. The compressed flue gas after heat exchange is injected into the pores of the abandoned oil and gas well formation through the wellhead of a new well or an abandoned oil and gas well. The compressed flue gas is stored in the pores of the abandoned oil and gas well formation and exchanges heat with the earth's heat flow. The carbon dioxide in the flue gas is absorbed by the formation brine to achieve long-term storage, and then undergoes a mineralization reaction with diagenetic minerals such as feldspar to be permanently sealed. When the system lacks green electricity supply, the first automatic control valve is closed, and the second and third automatic control valves are opened. The high-temperature, high-pressure and purified gas is sprayed from the wellhead of a new well or an abandoned oil and gas well through the third automatic control valve into a multi-stage turbine for expansion to generate power and supply the power grid. The geothermal brine is pumped through the geothermal water injection pipeline by a water pump and then passed into the heat exchanger through the second automatic control valve. The heat exchanger is connected to the multi-stage turbine to provide heat for the decarbonized flue gas working fluid. The cooling water after heat exchange returns to the formation through the formation brine injection pipeline and is reheated by the formation heat flow to form a closed cycle.

[0011] The gas after doing work in the multi-stage turbine returns to normal temperature and pressure. At this time, the gas mainly consists of air and can be directly discharged into the atmosphere without treatment.

[0012] The number of multi-stage turbines is determined according to the geothermal level of new or abandoned oil and gas wells and the outlet pressure and temperature of the working fluid. The heat exchanger exchanges heat between each stage of the turbine, raising the temperature of the working fluid flowing out of the outlet of the previous turbine, and then flows into the next turbine to continue expanding and doing work. The turbine drives the generator to generate electricity, forming a closed cycle.

[0013] Part of the heat of the heat exchanger comes from the heat recovery device, and the other part comes from geothermal brine in the pores of the oil and gas well formation. The geothermal brine is at a certain height in the casing due to the underground pressure, and is pumped out through the groundwater injection pipeline by a water pump and flows into the heat exchanger to heat the high-pressure working fluid between the stages of the multi-stage turbine. The cooling water after heat exchange returns to the underground through the groundwater injection pipeline to form a closed cycle.

[0014] The present invention has the following beneficial effects: The present invention eliminates the high-energy-consuming separation process of carbon dioxide enrichment in flue gas through the coordinated work of three subsystems, realizes the reuse of abandoned oil and gas wells, flexible peak regulation of renewable energy, and spontaneous decarbonization of industrial flue gas, and spontaneously utilizes geothermal resources, uses new wells or abandoned oil and gas wells, and uses abandoned strata as a medium for photovoltaic and wind power energy storage and spontaneous carbon sequestration, converting surplus photovoltaic and wind power storage energy into compressed flue gas potential energy; The compressed flue gas is heated by geothermal energy deep underground, and the carbon dioxide in the flue gas is spontaneously absorbed by the underground salt water layer and mineralized and permanently sealed. When electricity is needed, due to the low density, viscosity and low pressure of the gas, the gas is extracted and expanded to generate electricity and supply the power grid, forming an innovative joint charging and discharging mode, which can quickly respond to changes in grid load when needed, meet the peak load regulation needs of the grid and drive the consumption of new energy, while providing a spontaneous integrated solution for low-cost carbon reduction in factories; According to the volatility and size of photovoltaic and wind power, the automatic control system controls the opening and power of valves, compressors and other equipment to adapt to the fluctuating energy supply mode of photovoltaic and wind power to the greatest extent and reduce energy consumption. At the same time, the excess photovoltaic and wind power that cannot be absorbed is stored in a high-value manner, responding quickly during peak power consumption periods in the power grid, alleviating power shortage pressure, and assisting the power grid in smoothing out peak-to-valley differences and reducing peak loads. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a structural schematic diagram of the present invention.

[0017] In the figure: 1. Flue gas injection subsystem; 2. Deep carbon sequestration and energy storage combined subsystem; 3. Geothermal enhanced compressed flue gas power generation subsystem 4. Motor; 5-1. Compression device; 5-2. Heat recovery device; 6. Abandoned oil and gas wells; 7. Photovoltaic wind power; 8-1. Casing; 8-2. Groundwater injection pipeline; 8-3. Water pump; 9-1. Multi-stage turbine; 9-2. Heat exchanger; 10. Generator; 11. Power grid; 12. Factory flue gas; 13. Oil and gas well formation pores; 14. Centralized computing controller; 15-1. Green electricity detection controller; 15-2. Flue gas compression flow detection controller; 15-3. Heat recovery and reuse temperature detection controller; 15-4. Power generation detection controller; 15-5. Working fluid flow detection controller; F1. First automatic control valve; F2. Second automatic control valve; F3. Third automatic control valve; M1. First flow meter; M2. Second flow meter. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. 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.

[0019] The flue gas discharged from the factory is collected, dusted, desulfurized, denitrified and compressed, and then injected into new or abandoned oil and gas wells through pipelines, especially into saline layers at a depth of 1,000 meters. The carbon dioxide in the flue gas undergoes absorption and mineralization reactions under the temperature and pressure conditions in the deep formations, and reacts with the salt water and diagenetic minerals such as plagioclase in the formations to form carbonate minerals such as calcite, thereby achieving permanent storage of carbon dioxide. The flue gas maintains high pressure in the formations and a certain temperature through the geothermal flow, such as the pressure at about 28MPa and 90-120℃ at 3,000 meters. When the power grid has a demand for electricity, the high-temperature and high-pressure gas stored in the formation has a low density and a small wellhead pressure drop, and can be used as a working fluid to drive the turbine to expand and generate electricity. The system can not only effectively meet the peak-shaving and absorption needs of the power grid, but also ensure that the flue gas collected by the factory (especially the thermal power plant) is effectively treated at low cost and permanently sealed in the deep salt water layer, reducing atmospheric carbon emissions. This technical solution effectively solves the problems of reuse of abandoned oil and gas wells, peak-shaving and absorption of renewable electricity, and carbon sequestration of industrial flue gas. In the context of global energy transformation, it has important environmental benefits and economic value.

[0020] like Figure 1 As shown, the abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas includes a flue gas injection subsystem 1, a deep carbon sequestration and energy storage combined subsystem 2 and a geothermal enhanced compressed flue gas power generation subsystem 3; wherein, the flue gas injection subsystem 1 includes a compression device 5-1, the inlet of the compression device 5-1 is connected to the factory exhaust flue gas 12 outlet, the compression device 5-1 is connected to the heat recovery device 5-2 for heat exchange, the compression device 5-1 is provided with kinetic energy by a motor 4, and the motor 4 is powered by photovoltaic wind power 7; a first automatic control valve F1 and a first flow meter M1 are provided on the pipeline connecting the outlet of the compression device 5-1 and the wellhead 6 of the abandoned oil and gas well; The flue gas injection subsystem 1 also includes a green power detection controller 15-1 and a flue gas compression flow detection controller 15-2. The green power detection controller 15-1 detects the power generation power of the photovoltaic wind power 7, sends a signal to the centralized computing controller 14 and receives a feedback signal from the centralized computing controller 14, controls the working power of the motor 4, and adjusts the flue gas compression ratio of the compression device 5-1; the flue gas compression flow detection controller 15-2 detects the flow size at the first flow meter M1, sends a signal to the centralized computing controller 14 and receives a feedback signal from the centralized computing controller 14, controls the opening and closing state of the first automatic control valve F1, and ensures that the compressed flue gas is injected into the underground and stored.

[0021] The deep-earth carbon sequestration and energy storage combined subsystem 2 includes a casing 8-1, a groundwater injection pipeline 8-2 is arranged in the multiple layers of well completion in the casing 8-1, one inlet of the casing 8-1 is connected to the compressed flue gas outlet of the compression device 5-1, one outlet of the casing 8-1 is connected to the formation pores 13 of the abandoned oil and gas well, the inlet of the groundwater injection pipeline 8-2 is connected to the cooling water outlet of the heat exchanger 9-2, and the outlet of the groundwater injection pipeline 8-2 is connected to the groundwater liquid level in the casing 8-1; the groundwater injection pipeline 8-2 is provided with a water pump 8-3, a second flow meter M2 and a second automatic control valve F2; The geothermally enhanced compressed flue gas power generation subsystem 3 includes a multi-stage turbine 9-1, the inlet of the multi-stage turbine 9-1 is connected to the compressed high-temperature flue gas outlet of the third automatic control valve F3 at the wellhead 6 of a new well or an abandoned oil and gas well, the outlet of the multi-stage turbine 9-1 is connected to the outside atmosphere, the multi-stage turbine 9-1 exchanges heat with the heat exchanger 9-2, the inlet of the heat exchanger 9-2 is connected to the circulating steam outlet of the heat recovery device 5-2 on one path, and is connected to the underground hot water outlet of the groundwater injection pipeline 8-2 on the other path, the outlet of the heat exchanger 9-2 is connected to the circulating water inlet of the heat recovery device 5-2 on one path, and is connected to the cooling water inlet of the groundwater injection pipeline 8-2 on the other path, and the multi-stage turbine 9-1 is used to drive the generator 10 to generate electricity and supply the power grid 11.

[0022] The geothermally enhanced compressed flue gas power generation subsystem 3 also includes a power generation detection controller 15-4 and a working fluid flow detection controller 15-5. The power generation detection controller 15-4 detects the peak and valley state of the power grid 11, sends a signal to the centralized computing controller 14 and receives a feedback signal from the centralized computing controller 14, controls the workload and start and stop time of the multi-stage turbine 9-1, assists the power grid in smoothing the peak and valley difference, and alleviates the power shortage pressure; the working fluid flow detection controller 15-5 detects the flow size at the second flow meter M2, sends a signal to the centralized computing controller 14 and receives a feedback signal from the centralized computing controller 14, controls the opening and closing states of the second automatic control valve F2 and the third automatic control valve F3, and ensures that the high-temperature compressed working fluid entering the multi-stage turbine 9-1 and the geothermal brine flow of the heat exchanger 9-2 meet the power generation demand; The geothermally enhanced compressed flue gas power generation subsystem 3 also includes a heat recovery and reuse temperature detection controller 15-3. The heat recovery and reuse temperature detection controller 15-3 detects the heat demand of the heat recovery device 5-2 and the heat exchanger 9-2, sends a signal to the centralized computing controller 14 and receives a feedback signal from the centralized computing controller 14, controls the valve opening of the second automatic control valve F2 and the outlet flow rate of the heat exchange medium of the heat recovery device 5-2, and ensures the heat demand when the underground compressed decarbonized flue gas expands to generate power.

[0023] Through the coordinated work of the three subsystems, the high-energy-consuming separation process of carbon dioxide enrichment in flue gas is eliminated, and the reuse of abandoned oil and gas wells, flexible peak-shaving of renewable energy, and spontaneous decarbonization of industrial flue gas are achieved. Geothermal resources are spontaneously utilized, and new wells or abandoned oil and gas wells are used. Abandoned strata are used as a medium for photovoltaic and wind power energy storage and spontaneous carbon sequestration, and surplus photovoltaic and wind power waiting for storage energy is converted into compressed flue gas potential energy; the compressed flue gas is heated by geothermal energy in the deep earth, and the carbon dioxide in the flue gas is spontaneously absorbed and mineralized and permanently sealed by the underground salt water layer. When electricity is needed, due to the low density, viscosity and low pressure of the gas, the extracted gas is self-expanded and expanded to generate electricity and supply the power grid, forming an innovative joint charging and discharging mode, which can quickly respond to changes in grid load when needed, meet the peak-shaving needs of the grid and drive the consumption of new energy, and at the same time provide a spontaneous integrated solution for low-cost carbon reduction in factories; According to the volatility and size of photovoltaic wind power 7, the automatic control system controls the opening and power of valves, compressors and other equipment to adapt to the fluctuating energy supply mode of photovoltaic wind power to the greatest extent and reduce energy consumption. At the same time, the excess photovoltaic wind power that cannot be absorbed is stored in a high-value manner, responding quickly during the peak period of power consumption in the power grid, alleviating the pressure of power shortage, and assisting the power grid in smoothing the peak-to-valley difference and reducing the peak to fill the valley.

[0024] A further improvement of the present invention is that the compression device 5-1 is driven by a motor 4, and the motor 4 is turned on or off in coordination with the fluctuation of photovoltaic wind power 7 or other power to be adjusted, so as to achieve minute-level response and compress industrial flue gas for energy storage.

[0025] A further improvement of the present invention is that the high-temperature compressed flue gas at the outlet of the compression device 5-1 is passed into the heat recovery device 5-2, and the recovered heat is used to heat the working medium in the multi-stage turbine 9-1 or external steam.

[0026] A further improvement of the present invention is that the geothermally enhanced compressed flue gas power generation subsystem 3 uses compressed factory flue gas as a working medium.

[0027] A further improvement of the present invention is that when the system has green electricity or other electricity to be adjusted, the first automatic control valve F1 is opened, and the second control valve F2 and the third control valve F3 are closed. At this time, the motor 4 driven by the photovoltaic wind power 7 or other electricity to be adjusted provides power to the compression device 5-1 to compress the flue gas collected from the factory, and the outlet high-temperature and high-pressure flue gas is heat-exchanged through the heat recovery device 5-2. The compressed flue gas after heat exchange is injected into the formation pores 13 of the abandoned oil and gas well through the wellhead 6 of the new well or the abandoned oil and gas well. The compressed flue gas is stored in the formation pores 13 of the abandoned oil and gas well and exchanges heat with the earth's heat flow. The carbon dioxide in the flue gas is absorbed by the formation brine to achieve long-term storage, and then undergoes mineralization reaction with diagenetic minerals such as feldspar to be permanently sealed. When the system lacks green electricity supply, the first automatic control valve F1 is closed, and the second automatic control valve F2 and the third automatic control valve F3 are opened. The high-temperature, high-pressure and purified gas is sprayed from the wellhead 6 of the new well or the abandoned oil and gas well into the multi-stage turbine 9-1 to expand and generate power to supply the power grid 11. The geothermal brine is pumped by the water pump 8-3 through the geothermal water injection pipeline 8-2 and passed into the heat exchanger 9-2. The heat exchanger 9-2 is connected to the multi-stage turbine 9-1 to provide heat for the decarbonized flue gas working medium. The cooling water after heat exchange returns to the formation through the groundwater injection pipeline 8-2 and is reheated by the formation heat flow to form a closed cycle.

[0028] The gas after doing work in the multi-stage turbine 9-1 returns to normal temperature and pressure. At this time, the gas mainly consists of air and can be directly discharged into the atmosphere without treatment.

[0029] The number of stages of the multi-stage turbine 9-1 is determined according to the ground temperature level at the wellhead 6 of a new or abandoned oil and gas well and the outlet pressure and temperature of the working fluid. The heat exchanger 9-2 performs heat exchange between each stage of the turbine, and after increasing the temperature of the working fluid flowing out of the outlet of the previous stage turbine, it flows into the next stage turbine to continue to expand and do work. The turbine drives the generator 10 to generate electricity, forming a closed cycle.

[0030] Part of the heat of the heat exchanger 9-2 comes from the heat recovery device 5-2, and the other part comes from the geothermal brine in the pores 13 of the oil and gas well formation. The geothermal brine is at a certain height in the casing 8-1 due to the underground pressure, and is pumped out through the groundwater injection pipeline 8-2 by the water pump 8-3 and flows into the heat exchanger 9-2 to heat the high-pressure working fluid between the stages of the multi-stage turbine 9-1. The cooling water after heat exchange returns to the underground through the groundwater injection pipeline 8-2 to form a closed cycle.

[0031] The abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas is operated. When the system has green electricity or other electricity to be adjusted, the first automatic control valve F1 is opened, and the second control valve F2 and the third control valve F3 are closed. At this time, the motor 4 driven by photovoltaic wind power 7 or other electricity to be adjusted provides power to the compression device 5-1 to compress the flue gas collected from the factory. The outlet high-temperature and high-pressure flue gas is heat-exchanged through the heat recovery device 5-2. The compressed flue gas after heat exchange is injected into the abandoned oil and gas well formation pores 13 through the wellhead 6 of the new well or abandoned oil and gas well. The compressed flue gas is stored in the abandoned oil and gas well formation pores 13 and exchanges heat with the earth's heat flow. The carbon dioxide in the flue gas is absorbed by the formation brine to achieve long-term storage, and then undergoes mineralization reaction with diagenetic minerals such as feldspar to be permanently sealed. When the system lacks green electricity supply, the first automatic control valve F1 is closed, and the second automatic control valve F2 and the third automatic control valve F3 are opened. The high-temperature, high-pressure and purified gas is sprayed from the wellhead 6 of the new well or the abandoned oil and gas well into the multi-stage turbine 9-1 to expand and generate power to supply the power grid 11. The geothermal brine is pumped by the water pump 8-3 through the geothermal water injection pipeline 8-2 and passed into the heat exchanger 9-2. The heat exchanger 9-2 is connected to the multi-stage turbine 9-1 to provide heat for the decarbonized flue gas working medium. The cooling water after heat exchange returns to the formation through the groundwater injection pipeline 8-2 and is reheated by the formation heat flow to form a closed cycle.

[0032] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. Abandoned oil and gas well carbon sequestration and energy storage peak regulation system based on industrial flue gas, characterized in that: It includes a flue gas injection subsystem (1), a deep carbon sequestration and energy storage combined subsystem (2) and a geothermal enhanced compressed flue gas power generation subsystem (3); The flue gas injection subsystem (1) is located on the surface, compresses the flue gas (12) discharged by the factory and injects it into the wellhead (6) of a new well or an abandoned oil and gas well; it comprises a motor (4), the motor (4) is connected to a compression device (5-1); the compression device (5-1) is equipped with a compression heat recovery device (5-2), the outlet of the compression device (5-1) is connected to the wellhead (6) of the abandoned oil and gas well, and the photovoltaic wind power (7) is connected to the motor (4); a first automatic control valve (F1) and a first flow meter (M1) are arranged on the pipeline connecting the outlet of the compression device (5-1) and the wellhead (6) of the new well or the abandoned oil and gas well; The deep-earth carbon sequestration and energy storage combined subsystem (2) is located underground, and utilizes the flue gas compressed by the flue gas injection subsystem (1) to be injected into a new well or an abandoned oil and gas well for storage and heating; it comprises a casing (8-1), and a groundwater injection pipeline (8-2) arranged in the casing (8-1); a water pump (8-3) is arranged on the groundwater injection pipeline (8-2); The geothermally enhanced compressed flue gas power generation subsystem (3) is located on the surface and releases the high-temperature and high-pressure decarbonized flue gas working fluid in the deep-earth carbon sequestration and energy storage combined subsystem (2) to perform work; it comprises a multi-stage turbine (9-1), the multi-stage turbine (9-1) is connected to a generator (10), and a heat exchanger (9-2) is arranged between the stages of the multi-stage turbine (9-1); a third automatic control valve (F3) is arranged on the pipeline connecting the multi-stage turbine (9-1) and the wellhead (6) of a new well or abandoned oil and gas well; a second automatic control valve (F2) and a second flow meter (M2) are arranged on the pipeline connecting the heat exchanger (9-2) and the groundwater injection pipeline (8-2); and the generator (10) is connected to a power grid (11) for power supply.

2. According to claim 1, the abandoned oil and gas well carbon sequestration and energy storage peak regulation system based on industrial flue gas is characterized in that: In the flue gas injection subsystem (1), when the supporting photovoltaic wind power (7) generates a large amount of green electricity, the green electricity drives the motor (4) to work, and the motor (4) provides power for the compression device (5-1), compressing the factory to discharge flue gas (12), and at the same time opening the first automatic control valve (F1) to inject the compressed flue gas into the ground through the pipeline at the wellhead (6) of the new well or abandoned oil and gas well, and the gas injection process continues until there is no green electricity, and then closing the first automatic control valve (F1), the second automatic control valve (F2) and the third automatic control valve (F3) to maintain the underground flue gas storage environment; The compression device (5-1) generates heat during the flue gas compression process, and the heat is recovered by the heat recovery device (5-2) and sent to the heat exchanger (9-2) for further use.

3. The abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas according to claim 1 is characterized in that: In the deep-earth carbon storage and energy storage combined subsystem (2), when the compressed flue gas is injected into the pores (13) of the new or abandoned oil and gas well formation, the formation brine filling the pores quickly absorbs the carbon dioxide in the mixed gas, achieving long-term storage of the carbon dioxide; the diagenetic minerals in the formation will undergo a mineralization reaction with the absorbed carbon dioxide, achieving permanent storage of the carbon dioxide.

4. The abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas according to claim 1 is characterized in that: In the geothermal enhanced compressed flue gas power generation subsystem (3), when power is needed, the second automatic control valve (F2) and the third automatic control valve (F3) are opened, and the first automatic control valve (F1) is closed, so that the underground decarbonized flue gas can flow into the multi-stage turbine (9-1) as a high-temperature compressed working fluid through the pipeline at the wellhead (6) of a new well or an abandoned oil and gas well to expand and perform work, and drive the generator (10) to generate electricity to supply the power grid (11).

5. According to claim 4, the abandoned oil and gas well carbon sequestration and energy storage peak regulation system based on industrial flue gas is characterized in that: In the geothermally enhanced compressed flue gas power generation subsystem (3), the multi-stage turbine (9-1) is provided with a plurality of turbine devices according to the pressure and temperature levels of the working fluid, and a heat exchanger (9-2) is provided between each stage of the turbine devices to utilize geothermal heat and recovered heat to heat the working fluid for further expansion and work.

6. The abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas according to claim 5 is characterized in that: In a geothermal-enhanced compressed flue gas power generation subsystem (3), part of the heat of the heat exchanger (9-2) comes from a heat recovery device (5-2), and the other part comes from geothermal brine in the pores (13) of the oil and gas well formation. The geothermal brine is in the casing (8-1) due to underground pressure, and is pumped out through a water pump (8-3) through a groundwater injection pipeline (8-2), and flows into the heat exchanger (9-2) through an opened second automatic control valve (F2) and a second flow meter (M2). The heat exchanger (9-2) uses the geothermal brine and the recovered heat to heat the high-pressure working fluid between the stages of the multi-stage turbine (9-1), and the cooling water after heat exchange returns to the underground through the groundwater injection pipeline (8-2) to form a closed cycle.

7. The abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas according to claim 6 is characterized in that: In the geothermal enhanced compressed flue gas power generation subsystem (3), during the power generation stage, geothermal water flows into the auxiliary heating system heat exchanger (9-2) through the groundwater injection pipeline (8-2), and then the cooling water after heat exchange is reinjected into the formation through the groundwater injection pipeline (8-2) to achieve geothermal collection. During the power storage stage, the compressed original flue gas enters the formation through the casing (8-1). During the power generation stage, the decarbonized compressed flue gas is discharged through the casing (8-1) and connected to the ground multi-stage turbine (9-1) and generator (10) power generation subsystem.

8. The abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas according to claim 2 is characterized in that: The flue gas injection subsystem (1) also includes a green power detection controller (15-1) and a flue gas compression flow detection controller (15-2). The green power detection controller (15-1) detects the power generation of the photovoltaic wind power (7), sends a signal to the centralized computing controller (14) and receives a feedback signal from the centralized computing controller (14), controls the working power of the motor (4), and adjusts the flue gas compression ratio of the compression device (5-1); the flue gas compression flow detection controller (15-2) detects the flow size at the first flow meter (M1), sends a signal to the centralized computing controller (14) and receives a feedback signal from the centralized computing controller (14), controls the opening and closing state of the first automatic control valve (F1), and ensures that the compressed flue gas is injected into the ground and stored.

9. The abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas according to claim 4 is characterized in that: The geothermal-enhanced compressed flue gas power generation subsystem (3) also includes a power generation detection controller (15-4) and a working fluid flow detection controller (15-5), wherein the power generation detection controller (15-4) detects the peak and valley state of the power grid (11), sends a signal to the centralized computing controller (14) and receives a feedback signal from the centralized computing controller (14), controls the working load and start and stop time of the multi-stage turbine (9-1), assists the power grid in smoothing the peak and valley difference, and alleviates the power shortage pressure; the working fluid flow detection controller (15-5) detects the flow size at the second flow meter (M2), sends a signal to the centralized computing controller (14) and receives a feedback signal from the centralized computing controller (14), controls the opening and closing states of the second automatic control valve (F2) and the third automatic control valve (F3), and ensures that the high-temperature compressed working fluid entering the multi-stage turbine (9-1) and the geothermal brine flow of the heat exchanger (9-2) meet the power generation demand.

10. The abandoned oil and gas well carbon sequestration and energy storage peak-shaving system based on industrial flue gas according to claim 9, characterized in that: The geothermally enhanced compressed flue gas power generation subsystem (3) also includes a heat recovery and reuse temperature detection controller (15-3), wherein the heat recovery and reuse temperature detection controller (15-3) detects the heat demand of the heat recovery device (5-2) and the heat exchanger (9-2), sends a signal to the centralized computing controller (14) and receives a feedback signal from the centralized computing controller (14), controls the valve opening of the second automatic control valve (F2) and the outlet flow rate of the heat exchange medium of the heat recovery device (5-2), and ensures the heat demand when the underground compressed decarbonized flue gas expands to generate power.

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