A geothermal energy storage system

Abstract

The present invention discloses a geothermal energy storage system, comprising a solar energy collection system, a geothermal heat exchange system, and a heat energy conversion system. The system utilizes the pressure of compressed air itself to drive the gas flow and exchange heat with geothermal energy, thereby saving investment in geothermal energy utilization. The system fully utilizes the thermal energy of deep-layer hot dry rocks, and uses air for heat exchange only, thereby avoiding the corrosion problem caused by water heat exchange and extending the life of the system. The present invention converts geothermal energy into thermal energy through a geothermal heat exchange system, and after the water in the evaporator is evaporated into steam by the thermal energy, the steam drives the turbine to rotate, so that the turbine generates electricity after generating electricity, thereby realizing the conversion of geothermal energy into electrical energy. The low-temperature and high-pressure gas after the secondary heat exchange can be stored, and when it is needed, the air potential energy is converted into electrical energy for release, thereby realizing the secondary effective utilization of geothermal energy, which is more energy-saving and environmentally friendly.

Description

Technical Field

[0001] The present invention relates to the technical field of geothermal resource utilization, and in particular to an energy storage system based on geothermal energy. Background Art

[0002] Geothermal energy is natural heat extracted from the earth's crust. This energy comes from the molten rock inside the earth and exists in the form of heat. It is the energy that causes volcanic eruptions and earthquakes. The temperature inside the earth is as high as 7000℃, and at a depth of 80 to 100 miles, the temperature drops to 650 to 1200℃. Through the flow of groundwater and the flow of molten rock to the earth's crust 1 to 5 kilometers below the ground, heat can be transferred to places closer to the ground. The high-temperature molten rock heats the nearby groundwater, and this heated water eventually seeps out of the ground. The simplest and most cost-effective way to use geothermal energy is to directly access these heat sources and extract their energy. Geothermal energy is a renewable resource.

[0003] Geothermal energy is a new clean energy. With the increasing environmental awareness and energy shortage, the rational development and utilization of geothermal resources has become more and more popular. The geothermal energy stored within 2,000 meters from the surface is 250 billion tons of standard coal. The national geothermal exploitable resources are 6.8 billion cubic meters per year, containing 973 trillion kilojoules of geothermal heat. In terms of geothermal utilization scale, my country has been ranked first in the world in recent years, and has been growing steadily at a rate of nearly 10% per year.

[0004] Geothermal power generation is actually the energy conversion process of converting underground thermal energy into mechanical energy, and then converting mechanical energy into electrical energy, or geothermal power generation. The developed geothermal resources are mainly steam type and hot water type, so geothermal power generation is also divided into two categories.

[0005] Most of the existing technologies use water from geothermal water to input steam into a steam turbine to do work. However, when using thermal energy to heat water, long-term heating will cause scale to form on the inner wall of the container, which will reduce the utilization rate of heat conversion, thereby greatly wasting resources and easily causing corrosion problems. Summary of the invention

[0006] The object of the present invention is to provide a geothermal energy based energy storage system to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions: The present invention provides a geothermal energy based energy storage system, including a solar energy collection system, a geothermal heat exchange system, and a heat energy conversion system; A solar energy collection system comprises a solar panel, a storage battery electrically connected to the solar panel, the storage battery is connected to a heater, air is passed into the heater, the inlet of the heater is connected to the outlet of a first air compressor, the inlet of the first air compressor is connected to the atmosphere, the outlet of the heater is connected to the inlet of a second air compressor, and the outlet of the second air compressor is connected to the inlet of the heater; the solar energy collection system heats the air by converting solar energy into electrical energy temporarily stored in the storage battery to supply power to the heater; The geothermal heat exchange system includes a heat exchange pipe, the inlet of the heat exchange pipe is connected to the outlet of the heater, and the outlet of the heat exchange pipe is connected to the heat energy conversion system; high-temperature and high-pressure air is obtained by heat exchange with the middle and deep layers of geothermal energy.

[0008] The heat energy conversion system includes a first heat exchange unit and a second heat exchange unit. The heat energy input port of the first heat exchange unit is connected to the outlet of the heat exchange pipe, the heat energy output port of the first heat exchange unit is connected to the heat energy input port of the second heat exchange unit, and the heat energy output port of the second heat exchange unit is connected to the inlet of the heat exchange pipe; the input port of the conversion medium of the first heat exchange unit is connected to the conversion medium delivery pump, and the steam output port of the conversion medium of the first heat exchange unit is connected to the steam turbine, and the steam turbine is connected to the electric energy storage unit; the input port of the conversion medium of the second heat exchange unit is connected to the conversion medium delivery pump, and the output port of the conversion medium of the second heat exchange unit is connected to the input port of the conversion medium of the first heat exchange unit; a valve is arranged between the conversion medium delivery pump and the input port of the conversion medium of the first heat exchange unit. High temperature and high pressure air converts water into steam, and steam is used as the power of the steam turbine to start the operation of the steam turbine, further convert mechanical energy into electrical energy, and store the electrical energy in the electrical energy storage unit.

[0009] Furthermore, the pipe inside the heater is S-shaped, which increases the heat exchange time and improves the heat exchange efficiency.

[0010] Furthermore, a first temperature sensor and a first pressure sensor are provided at the outlet of the heater. The setting of the temperature sensor and the pressure sensor facilitates the setting of the system, and the geothermal heat exchange system is entered when the temperature and pressure reach the preset temperature and pressure range.

[0011] Further, the first heat exchange unit includes a heat exchange body, one end of the heat exchange body is provided with an input port of the conversion medium of the first heat exchange unit, the upper part of the other end of the heat exchange body is provided with an output port of the conversion medium of the first heat exchange unit, and the lower part is provided with a conversion medium liquid output port of the first heat exchange unit, and the two sides of the lower end of the heat exchange body are provided with a heat energy input port of the first heat exchange unit and a heat energy output port of the first heat exchange unit; a honeycomb heat exchange tube is provided in the heat exchange body, and a first positioning plate and a second positioning plate are provided at both ends of the heat exchange tube, and the heat exchange tube passes through the first positioning plate and the second positioning plate, and the first positioning plate and the heat exchange body form a conversion medium input cavity, and the second positioning plate and the heat exchange body form a conversion medium output cavity, and the heat energy input port of the first heat exchange unit and the heat energy output port of the first heat exchange unit are both placed between the first positioning plate and the second positioning plate. The structure of the first heat exchange unit is the same as that of the second heat exchange unit. The internal structure of the first heat exchange unit allows water to flow in, and the surrounding high-temperature and high-pressure steam is heated, thereby increasing the contact area and improving the heat exchange efficiency.

[0012] Furthermore, the liquid outlet of the conversion medium of the first heat exchange unit is also connected to the outlet of the conversion medium of the second heat exchange unit. The air after heat exchange in the first heat exchange unit enters the second heat exchange unit for further preheating water, thereby improving the steam conversion efficiency of the first heat exchange unit. And the low-temperature and high-pressure gas after the secondary heat exchange can return to the heat exchange pipeline for heat exchange; as another specific embodiment of the present invention, the low-temperature and high-pressure gas after the secondary heat exchange can be stored, and when it is needed, the air potential energy is converted into electrical energy for release, thereby realizing the secondary effective utilization of geothermal energy, which is more energy-saving and environmentally friendly.

[0013] Furthermore, the heat energy input port of the first heat exchange unit and the heat energy output port of the first heat exchange unit are both provided with a second temperature sensor and a second pressure sensor, the input port of the conversion medium of the first heat exchange unit and the output port of the conversion medium of the first heat exchange unit are both provided with a third temperature sensor and a third pressure sensor, the heat energy input port of the second heat exchange unit and the heat energy output port of the second heat exchange unit are both provided with a fourth temperature sensor and a fourth pressure sensor, and the input port of the conversion medium of the second heat exchange unit and the output port of the conversion medium of the second heat exchange unit are both provided with a fifth temperature sensor and a fifth pressure sensor. The setting of each temperature sensor and pressure sensor can safely and effectively control the operation of each system, and regulate the operation of air and water according to whether the temperature and pressure are within the preset temperature and pressure range.

[0014] Furthermore, a piston, a sixth pressure sensor and a compressed air chamber are arranged inside the first air compression device, and the compressed air chamber is provided with an inlet of the first air compression device and an outlet of the first air compression device. The inlet and the outlet are both provided with solenoid valves, and the solenoid valve and the piston are communicatively connected. When pumping air, the inlet valve is opened and the outlet valve is closed, and when compressing the gas, the inlet is closed and the outlet is opened; the second air compression device has the same structure as the first air compression device, and the first air compression device and the second air compression device cooperate to circulate air pumping and compression, and the air pressure becomes higher and higher. When the preset pressure range is reached, the air is ventilated into the geothermal heat exchange system.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention utilizes the pressure of compressed air itself to drive the gas flow and exchange heat with geothermal energy, thus saving investment in geothermal energy utilization; fully utilizing the thermal energy of medium-deep hot dry rocks and simply exchanging heat with air, thus avoiding the corrosion problem caused by using water for heat exchange and extending the life of the system.

[0016] The present invention converts geothermal energy into thermal energy through a geothermal heat exchange system. After the water in the evaporator is evaporated into steam by the thermal energy, the steam drives the steam turbine to rotate, so that the steam turbine generates electricity after generating electricity, thereby realizing the conversion of geothermal energy into electrical energy. The low-temperature and high-pressure gas after the secondary heat exchange can be stored, and when it is needed, the air potential energy is converted into electrical energy for release, thereby realizing the secondary effective utilization of geothermal energy, which is more energy-saving and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of a geothermal energy storage system according to the present invention; Figure 2 It is a schematic diagram of the structure of the first heat exchange unit of the present invention.

[0018] Description of Reference Numerals In the figure: 1. first air compression device; 101. piston; 102. compressed air chamber; 2. second air compression device; 3. heater; 4. geothermal heat exchange system; 401. heat exchange pipe; 5. first heat exchange unit; 501. heat exchange body; 502. conversion medium input chamber; 503. conversion medium output chamber; 504. first positioning plate; 505. heat exchange tube; 506. conversion medium input port of the first heat exchange unit; 507. conversion medium output port of the first heat exchange unit; 508. conversion medium liquid output port of the first heat exchange unit; 509. heat energy input port of the first heat exchange unit; 510. heat energy output port of the first heat exchange unit; 6. second heat exchange unit; 7. steam turbine; 8. electric energy storage unit. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention. Example 1

[0020] An energy storage system based on geothermal energy, comprising a solar energy collection system, a geothermal heat exchange system 4, and a heat energy conversion system; A solar energy collection system comprises a solar panel, a storage battery electrically connected to the solar panel, the storage battery is connected to a heater 3, air is passed into the heater 3, an inlet of the heater 3 is connected to an outlet of a first air compressor 1, an inlet of the first air compressor 1 is connected to the atmosphere, an outlet of the heater 3 is connected to an inlet of a second air compressor 2, and an outlet of the second air compressor 2 is connected to an inlet of the heater 3; an S-shaped pipe inside the heater 3, a first temperature sensor and a first pressure sensor are provided at an outlet of the heater 3; the solar energy collection system heats the air by converting solar energy into electrical energy temporarily stored in the storage battery to supply power to the heater 3; The geothermal heat exchange system 4 includes a heat exchange pipe 505 401, the inlet of the heat exchange pipe 505 401 is connected to the outlet of the heater 3, and the outlet of the heat exchange pipe 505 401 is connected to the heat energy conversion system; heat exchange with the middle and deep layers of geothermal energy obtains high-temperature and high-pressure air.

[0021] The heat energy conversion system includes a first heat exchange unit 5 and a second heat exchange unit 6, wherein a heat energy input port 509 of the first heat exchange unit is connected to an outlet of a heat exchange pipe 505 401, a heat energy output port 510 of the first heat exchange unit is connected to a heat energy input port of the second heat exchange unit 6, and a heat energy output port of the second heat exchange unit 6 is connected to an inlet of the heat exchange pipe 505 401; an input port 506 of a conversion medium of the first heat exchange unit is connected to a conversion medium delivery pump, and a steam output port of the conversion medium of the first heat exchange unit 5 is connected to a steam turbine 7, and the steam turbine 7 is connected to an electric energy storage unit 8; an input port of a conversion medium of the second heat exchange unit 6 is connected to a conversion medium delivery pump, and a conversion medium output port of the second heat exchange unit 6 is connected to an input port 506 of a conversion medium of the first heat exchange unit; and a valve is arranged between the conversion medium delivery pump and the input port 506 of a conversion medium of the first heat exchange unit. The high-temperature and high-pressure air converts water into steam, and the steam is used as the power of the steam turbine 7 to start the operation of the steam turbine 7, further converting mechanical energy into electrical energy, and storing the electrical energy in the electrical energy storage unit 8.

[0022] The first heat exchange unit 5 comprises a heat exchange body 501, one end of which is provided with an input port 506 of the conversion medium of the first heat exchange unit, the upper part of the other end of the heat exchange body 501 is provided with an output port 507 of the conversion medium of the first heat exchange unit, and the lower part is provided with a conversion medium liquid output port 508 of the first heat exchange unit, and both sides of the lower end of the heat exchange body 501 are provided with a heat energy input port 509 of the first heat exchange unit and a heat energy output port 510 of the first heat exchange unit; a honeycomb is provided in the heat exchange body 501. The heat exchange tube 505 is a nest-shaped heat exchange tube. The first positioning plate 504 and the second positioning plate are arranged at both ends of the heat exchange tube 505. The heat exchange tube 505 passes through the first positioning plate 504 and the second positioning plate. The first positioning plate 504 and the heat exchange body 501 form a conversion medium input cavity 502. The second positioning plate and the heat exchange body 501 form a conversion medium output cavity 503. The heat energy input port 509 of the first heat exchange unit and the heat energy output port 510 of the first heat exchange unit are both placed between the first positioning plate 504 and the second positioning plate. The first heat exchange unit 5 has the same structure as the second heat exchange unit 6. The internal structure of the first heat exchange unit 5 allows water to flow in, and the surrounding high-temperature and high-pressure steam is heated, thereby increasing the contact area and improving the heat exchange efficiency.

[0023] The liquid outlet of the conversion medium of the first heat exchange unit 5 is also connected to the outlet of the conversion medium of the second heat exchange unit 6. The air after heat exchange in the first heat exchange unit 5 enters the second heat exchange unit 6 for further preheating, thereby improving the steam conversion efficiency of the first heat exchange unit 5. And the low-temperature and high-pressure gas after the secondary heat exchange can return to the heat exchange pipe 505 and 401 for heat exchange; as another specific embodiment of the present invention, the low-temperature and high-pressure gas after the secondary heat exchange can be stored, and when it is needed, the air potential energy is converted into electrical energy for release, thereby realizing the secondary effective utilization of geothermal energy, which is more energy-saving and environmentally friendly.

[0024] The heat energy input port 509 of the first heat exchange unit and the heat energy output port 510 of the first heat exchange unit are both provided with a second temperature sensor and a second pressure sensor, the input port 506 of the conversion medium of the first heat exchange unit and the output port 507 of the conversion medium of the first heat exchange unit are both provided with a third temperature sensor and a third pressure sensor, the heat energy input port of the second heat exchange unit 6 and the heat energy output port of the second heat exchange unit 6 are both provided with a fourth temperature sensor and a fourth pressure sensor, and the input port of the conversion medium of the second heat exchange unit 6 and the output port of the conversion medium of the second heat exchange unit 6 are both provided with a fifth temperature sensor and a fifth pressure sensor. The setting of each temperature sensor and pressure sensor can safely and effectively control the operation of each system, and regulate the operation of air and water according to whether the temperature and pressure are within the preset temperature and pressure range.

[0025] A piston 101, a sixth pressure sensor and a compressed air chamber 102 are arranged inside the first air compression device 1. The compressed air chamber 102 is provided with an inlet of the first air compression device 1 and an outlet of the first air compression device 1. Solenoid valves are arranged at the inlet and the outlet. The solenoid valve and the piston 101 are communicatively connected. When pumping air, the inlet valve is opened and the outlet valve is closed. When compressing gas, the inlet is closed and the outlet is opened. The second air compression device 2 has the same structure as the first air compression device 1. The first air compression device 1 and the second air compression device 2 cooperate to circulate air pumping and compression. The air pressure becomes higher and higher. When the preset pressure range is reached, the air is ventilated into the geothermal heat exchange system 4.

[0026] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0027] It should be noted that the above content only illustrates the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications all fall within the protection scope of the claims of the present invention.

Claims

1. A geothermal energy storage system, characterized in that: Including solar energy collection system, geothermal heat exchange system, thermal energy conversion system; A solar energy collection system, comprising a solar panel, a storage battery electrically connected to the solar panel, the storage battery connected to a heater, air passing through the heater, the inlet of the heater connected to the outlet of a first air compressor, the inlet of the first air compressor connected to the atmosphere, the outlet of the heater connected to the inlet of a second air compressor, the outlet of the second air compressor connected to the inlet of the heater; The geothermal heat exchange system comprises a heat exchange pipe, the inlet of the heat exchange pipe is connected to the outlet of the heater, and the outlet of the heat exchange pipe is connected to the heat energy conversion system; The heat energy conversion system comprises a first heat exchange unit and a second heat exchange unit, wherein the heat energy input port of the first heat exchange unit is connected to the outlet of a heat exchange pipe, the heat energy output port of the first heat exchange unit is connected to the heat energy input port of the second heat exchange unit, and the heat energy output port of the second heat exchange unit is connected to the inlet of the heat exchange pipe; the input port of the conversion medium of the first heat exchange unit is connected to a conversion medium delivery pump, the steam output port of the conversion medium of the first heat exchange unit is connected to a steam turbine, and the steam turbine is connected to an electric energy storage unit; the input port of the conversion medium of the second heat exchange unit is connected to the conversion medium delivery pump, and the output port of the conversion medium of the second heat exchange unit is connected to the input port of the conversion medium of the first heat exchange unit; a valve is arranged between the conversion medium delivery pump and the input port of the conversion medium of the first heat exchange unit.

2. The geothermal energy storage system according to claim 1, characterized in that: The pipe inside the heater is S-shaped.

3. The geothermal energy storage system according to claim 1, characterized in that: The outlet end of the heater is provided with a first temperature sensor and a first pressure sensor.

4. The geothermal energy storage system according to claim 1, characterized in that: The first heat exchange unit comprises a heat exchange body, wherein an input port of a conversion medium of the first heat exchange unit is arranged at one end of the heat exchange body, an output port of the conversion medium of the first heat exchange unit is arranged at the upper part of the other end of the heat exchange body, and a liquid output port of the conversion medium of the first heat exchange unit is arranged at the lower part, and a heat energy input port of the first heat exchange unit and a heat energy output port of the first heat exchange unit are arranged on both sides of the lower end of the heat exchange body; a honeycomb-type heat exchange tube is arranged in the heat exchange body, and a first positioning plate and a second positioning plate are arranged at both ends of the heat exchange tube, and the heat exchange tube passes through the first positioning plate and the second positioning plate, the first positioning plate and the heat exchange body form a conversion medium input cavity, and the second positioning plate and the heat exchange body form a conversion medium output cavity, and the heat energy input port and the heat energy output port of the first heat exchange unit are both placed between the first positioning plate and the second positioning plate; the first heat exchange unit has the same structure as the second heat exchange unit.

5. The geothermal energy storage system according to claim 1, characterized in that: The liquid outlet of the conversion medium of the first heat exchange unit is also connected to the outlet of the conversion medium of the second heat exchange unit.

6. The geothermal energy storage system according to claim 1, characterized in that: The heat energy input port of the first heat exchange unit and the heat energy output port of the first heat exchange unit are both provided with a second temperature sensor and a second pressure sensor, the input port of the conversion medium of the first heat exchange unit and the output port of the conversion medium of the first heat exchange unit are both provided with a third temperature sensor and a third pressure sensor, the heat energy input port of the second heat exchange unit and the heat energy output port of the second heat exchange unit are both provided with a fourth temperature sensor and a fourth pressure sensor, and the input port of the conversion medium of the second heat exchange unit and the output port of the conversion medium of the second heat exchange unit are both provided with a fifth temperature sensor and a fifth pressure sensor.

7. The geothermal energy storage system according to claim 1, characterized in that: A piston, a sixth pressure sensor and a compressed air chamber are arranged inside the first air compression device, and the compressed air chamber is provided with an inlet of the first air compression device and an outlet of the first air compression device; the second air compression device has the same structure as the first air compression device.

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