A low-temperature energy underground gas storage device and method

Abstract

The application relates to a low-temperature energy underground gas storage device and method. The device comprises a liquid injection part, the liquid injection part comprising a vertical liquid injection pipeline and a liquid phase discharge main pipe, low-temperature liquid being sequentially injected into the vertical liquid injection pipeline and the liquid phase discharge main pipe from a liquid cargo tank; a storage part connected with the liquid phase discharge main pipe, the storage part comprising a plurality of liquid cavities and gas cavities, the liquid cavities being used for storing liquid, and the gas cavities being used for storing evaporated gas of the liquid cavities during the liquid injection period; a transfer gasification self-pressurization part and a high-pressure gas extraction part, the high-pressure gas extraction part comprising a high-pressure compressor and a heat exchanger. The method comprises the steps of discharging, static storage without external delivery and external delivery. When the external delivery is performed, the high-pressure compressor process is started, and after the gas in the gas cavities is delivered, the high-pressure gasification self-pressurization process is started. The liquid cavities adopt lower liquid outlet, the storage part and the gasification part are arranged in a staggered and stepped mode, liquid delivery and transfer are realized by using the height difference and gravity, pump equipment configuration is saved, and power cost is reduced.

Description

Technical Field

[0001] This invention relates to the fields of cryogenic energy storage, gasification and transmission technology, and in particular to a storage gasification gas extraction device and method based on a novel underground cryogenic energy liquid storage tank. Background Technology

[0002] Underground storage facilities, with their high storage capacity, low unit storage cost, and high security, have become an important guarantee and choice for strategic energy reserves. Traditional underground gas storage facilities rely on natural structures such as depleted oil and gas fields, abandoned mines, underground salt caverns, and salt mine layers as storage entities, storing energy in gaseous form, with limited energy storage per unit space. Underground oil storage facilities, on the other hand, can store liquid energy such as petroleum using underground salt caverns. With the development of underground storage technology, storing new cryogenic energy sources such as liquefied natural gas and liquid hydrogen in underground energy storage facilities as liquids can fully utilize underground space, increase energy storage per unit, and improve the turnover speed and capacity of the cryogenic energy industry chain.

[0003] Traditional gas storage facilities mainly follow foreign construction models, employing gas injection and extraction processes. Gas is injected using high-pressure compressors, and then processed through surface throttling, separation, dehydration, and purification devices before being metered and transported out. This approach has drawbacks such as high equipment investment, high compressor energy consumption, and complex surface processes. Traditional underground oil storage facilities, on the other hand, use an oil injection and extraction process.

[0004] However, the traditional processes for underground gas and oil storage facilities are not entirely suitable for the injection, production, and external transmission needs of underground liquid cryogenic energy storage facilities in such artificial cavity spaces. It is necessary to develop a new liquid injection and gas production process that combines the characteristics of the medium and the features of the cryogenic energy industry. Summary of the Invention

[0005] To address the aforementioned problems, the purpose of this invention is to provide a storage, gasification, and gas extraction unit, apparatus, and method for underground cryogenic energy storage facilities. Primarily targeting novel underground liquid storage methods for cryogenic energy, this invention proposes a liquid injection and gas extraction process. This process improves the unloading and storage efficiency of imported liquefied natural gas, liquid hydrogen, and other cryogenic energy sources. Furthermore, by rationally designing the ratio of liquid to gas chambers, incorporating a self-contained conveying unit, natural heat source gasification, and self-pressurized external transmission technologies, it reduces the configuration and use of compressors, effectively lowering operating energy consumption and simplifying the process flow.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A storage and extraction device for a cryogenic underground gas storage facility includes:

[0008] The liquid injection section includes a vertical liquid injection pipe and a liquid phase unloading main pipe. Cryogenic liquid is sequentially injected from the liquid cargo tank into the vertical liquid injection pipe and the liquid phase unloading main pipe.

[0009] The storage section is connected to the liquid phase unloading main pipe. The storage section includes multiple liquid chambers and gas chambers. The liquid chambers are used to store liquid, and the gas chambers are used to store the evaporated gas from the liquid chambers during the liquid injection period.

[0010] A transfer gasification self-pressurization unit is included, with a storage unit connected to it. The transfer gasification self-pressurization unit comprises at least two alternating gasification transfer tanks and corresponding heat exchange units.

[0011] The high-pressure gas extraction unit includes a high-pressure compressor and a heat exchanger. When there is an external transmission requirement, the gas in the gas chamber is first extracted through the exhaust pipe of the high-pressure compressor inlet main pipe and then through the heat exchanger to reach the external transmission temperature requirement before entering the external transmission pipeline.

[0012] Cooling coils are installed on the outside of the vertical injection pipes of the injection section. The low-temperature medium keeps the vertical injection pipes undercooled, preventing the low-temperature energy medium from directly vaporizing during the unloading process.

[0013] The storage unit is arranged with a liquid chamber in the middle and gas chambers on both sides. The configuration is reasonable according to the injection and production cycle, market demand, storage conditions and medium density characteristics. This ensures that the gas chambers can accommodate all the evaporated gas from the liquid chambers during periods when there is no external output. Both the liquid chambers and gas chambers are connected to the unloading main pipe through the feed pipe above the storage tank so that the liquid can enter the chambers.

[0014] Under normal conditions, the liquid chamber and the gas chamber are connected by an exhaust pipe above the liquid chamber, a low-pressure gas phase pipe, and an intake pipe above the gas chamber, with the valves on the pipes kept open to ensure that the evaporated gas in the liquid chamber can fill the intake gas phase space in a timely manner. A bypass is set in the intake pipe of the gas chamber. When the pressure in one gas chamber exceeds the set value, exhaust gas is discharged to the lower pressure gas chamber to equalize the pressure. Safety valves are set in both the liquid chamber and the gas chamber for overpressure relief. Gas replenishment valves are set in both the liquid chamber and the gas chamber for low-pressure gas replenishment.

[0015] The high-pressure gas extraction unit includes a temperature compensator, which is set according to the temperature requirements of the exported gas.

[0016] The switching interval of the gasification transfer tank in the transfer gasification self-pressurization unit can be determined according to the operating frequency. The tank capacity of the gasification transfer tank is determined according to the switching interval and the capacity of the external transmission pipeline. The transfer gasification self-pressurization unit is equipped with a liquid inlet pipeline and a liquid inlet control valve, which are connected to the liquid phase external transmission main pipeline. It is also equipped with a gas transmission pipeline and a gas transmission control valve, which are connected to the gas collection main pipeline. Furthermore, it is equipped with an exhaust pipeline and an exhaust control valve, which are connected to the gas connection main pipeline of the storage area, so as to discharge high-pressure gas into the low-pressure gas chamber and realize the pressure reduction of the gasification transfer tank.

[0017] The transshipment self-pressurizing vaporization unit is installed at a lower plane than the storage unit. The liquid chamber adopts a bottom-out liquid method, which facilitates the liquid to automatically flow into the vaporization unit under the action of gravity. Furthermore, the vaporization pressure of the vaporization transfer tank is slightly higher than the pressure of the external transmission main pipe, so as to lift the gas to the ground external transmission unit.

[0018] A storage and extraction method for a cryogenic energy underground gas storage facility utilizes the aforementioned storage and extraction device. During unloading, cryogenic energy from tank trucks or transport ships is injected into the liquid chamber of the storage unit via a pump and gravity through the unloading main pipe, the liquid phase main pipe, and the liquid inlet pipe above the liquid chamber. During static storage without external output, the liquid chamber and gas chamber are connected through the exhaust pipe above the liquid chamber, the gas phase connection main pipe, and the gas inlet pipe above the gas chamber. The evaporated gas from the liquid chamber enters the first gas chamber for accumulation and storage under the action of pressure and density differences. A bypass is set in the gas inlet pipe of the first gas chamber. When the pressure on one side is higher, the gas is discharged into the remaining low-pressure gas chambers through the gas phase connection main pipe. During external output, the high-pressure compressor process is started. After the gas in the gas chamber is completely transported, the high-pressure vaporization self-pressurization process is started.

[0019] The high-pressure compressor process includes: using the high-pressure compressor, the low-pressure gas in the first gas chamber is extracted through the exhaust pipe above the gas chamber and the high-pressure compressor inlet main pipe, and then enters the heat exchanger through the high-pressure compressor outlet pipe and the heat exchanger inlet pipe for heat exchange, and then enters the external transmission network through the external transmission main pipe.

[0020] The high-pressure gasification self-pressurization process includes:

[0021] S1, the liquid medium enters the gasification transfer tank through the liquid phase external transmission main pipe and the liquid inlet pipe above the gasification transfer tank. At this time, the heat exchange section of the gasification transfer tank does not work, and the tank is kept at low pressure P1.

[0022] S2. After the liquid fills the vaporization and transfer tank, close its inlet valve and start the heat exchange unit to vaporize and pressurize the liquid in the tank.

[0023] S3, Simultaneously, open the liquid inlet valve above another gasification transfer tank to perform the feeding operation;

[0024] S4. After the pressure in the gasification transfer tank increases to P2, open the gas transmission valve above and the pressure regulating valve on the gas collection pipeline in the station to transport the saturated gas through the pipeline to the ground heating device.

[0025] S5, the gas is heated to the required temperature for external transmission by the ground heating device and then enters the external transmission network through the external transmission main;

[0026] S6. After the gasification transfer tank has finished its external output, open its exhaust valve to discharge the remaining high-pressure gas into the gas chamber, so as to help the gasification transfer tank reduce the pressure to the inlet pressure.

[0027] S7, after the gasification transfer tank is completely emptied, the feeding operation S1 is restarted.

[0028] In step S8, another gasification transfer tank continues operations S2 to S4. This cycle is repeated to achieve continuous gasification and external transmission.

[0029] Among them, the gasification pressure of the high-pressure gasification transfer tank is slightly higher than that of the external transmission main pipe, so as to lift the gas to the ground external transmission system. During the gasification process, when the heat exchange system is efficient enough to meet the external transmission temperature requirements, the process of using a heat exchanger for supplementary heating can be omitted, so as to ensure the intensive use of the heat source.

[0030] This invention proposes a liquid injection and gas extraction process for a novel underground liquid storage method for cryogenic energy, filling a gap in the process flow of underground gas storage for cryogenic energy. Compared with traditional underground gas storage processes, it has the following advantages:

[0031] (1) The process of liquid injection for gas production saves energy. On the one hand, liquid storage makes full use of storage space; on the other hand, compared with the liquid production process, the unit energy consumption of gas production is lower.

[0032] (2) The gas is extracted by gasification and pressurization lifting, which reduces the configuration of compressors, saves power consumption in the gasification extraction process, and saves equipment investment and operating costs.

[0033] (3) Gasification is achieved by utilizing natural heat sources such as geothermal energy, thereby reducing the energy consumption of the production process.

[0034] (4) The liquid chamber adopts bottom liquid discharge, and the storage section and the vaporization section are arranged in a staggered stepped manner. The liquid is transported and transferred by utilizing the height difference and gravity, which saves on the configuration of pump equipment and reduces power costs. Attached Figure Description

[0035] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:

[0036] Figure 1 This is a schematic diagram of a liquid injection gas extraction process for a novel underground liquid storage method for cryogenic energy, according to an embodiment of the present invention.

[0037] Figure 2 This is a schematic diagram of a liquid injection gas extraction process for a novel underground liquid storage method for cryogenic energy, according to another embodiment of the present invention.

[0038] The markings in the attached diagram are as follows:

[0039] 1-First gas chamber; 2-Liquid chamber; 3-First vaporization transfer tank; 4-Second vaporization transfer tank; 5-Heat exchange section; 6-High-pressure compressor; 7-Heat exchanger; 8-Second gas chamber; 9-Vertical liquid injection pipe; 10-Liquid phase unloading main pipe; 11-Liquid phase external transmission main pipe; 12-Gas collection main pipe; 13-Gas connection main pipe; 14-High-pressure compressor inlet main pipe; 15-High-pressure compressor outlet pipe; 16-Heat exchanger inlet pipe; 17-External transmission main pipe; 18-Gas chamber exhaust pipe; 19-Gas chamber liquid inlet pipe; 20-Gas chamber air inlet pipe; 21-Gas chamber bypass exhaust pipe; 22-Liquid chamber liquid inlet pipe; 23-Liquid chamber exhaust pipe; 24-Liquid chamber liquid outlet pipe ; 25-Liquid inlet pipe of the first gasification transfer tank; 26-Gas delivery pipe of the first gasification transfer tank; 27-Gas chamber exhaust switch valve; 28-Gas chamber inlet valve; 29-Gas chamber bypass exhaust valve; 30-Liquid inlet control valve of the gas chamber; 31-Liquid inlet control valve of the liquid chamber; 32-Liquid exhaust valve of the liquid chamber; 33-Liquid outlet control valve of the liquid chamber; 34-Liquid inlet control valve of the first gasification transfer tank; 35-Gas delivery control valve of the first gasification transfer tank; 36-Gas collection pipe control valve; 37-Compressor outlet control valve; 38-Liquid inlet control valve of the second gasification transfer tank; 39-Exhaust valve of the first gasification transfer tank; 40-Exhaust pipe of the first gasification transfer tank; 41-Temperature replenisher; 42-Temperature replenisher outlet pipe. Detailed Implementation

[0040] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0041] like Figure 1 As shown, this embodiment provides a liquid injection and gas extraction process suitable for underground gas storage facilities for cryogenic energy. By using the liquid injection section, storage section, transfer gasification self-pressurization section and high-pressure gas extraction section, the cryogenic energy can be gravity unloading and transfer, efficient storage and low-energy-consumption pressurized external transmission can be achieved.

[0042] like Figure 2 As shown, when the heat exchange efficiency of the underground self-pressurized vaporization section is high, the heat replenishment process of the ground heat replenisher 41 can be omitted.

[0043] According to one embodiment of a liquid injection and gas extraction process suitable for a cryogenic energy underground gas storage facility, during the unloading operation, the liquid inlet control valve 31 of the liquid chamber is opened, and cryogenic energy from the tank truck or transport ship is injected into the liquid chamber 2 of the storage unit by means of a pump and gravity through the unloading main pipe 9, the liquid phase unloading main pipe 10, and the liquid inlet pipe 22 above the liquid chamber.

[0044] In static storage without external output, the liquid chamber exhaust valve 32 and the gas chamber inlet valve 28 are opened. The liquid chamber and the gas chamber are connected through the liquid chamber exhaust pipe 23 above the liquid chamber 2, the gas phase connection main pipe 13, and the gas chamber inlet pipe 20 above the gas chamber. Under the action of pressure difference and density difference, the evaporated gas in the liquid chamber enters the first gas chamber 1 for accumulation and storage.

[0045] A bypass exhaust pipe 21 is installed on the intake pipe of the first air chamber 1. When the pressure on one side is high, the bypass exhaust valve 29 is opened to discharge the gas into the other low-pressure air chambers through the gas phase connection main pipe 13.

[0046] In the external transmission mode, it is achieved by relying on the high-pressure compressor process and the high-pressure gasification self-pressurization process respectively.

[0047] During the high-pressure compressor process, valves 27 and 37 are opened. With the help of the high-pressure compressor 6, the low-pressure gas in the first gas chamber 1 is extracted through the exhaust pipe 18 above the gas chamber and the high-pressure compressor inlet main pipe 14. Then, it enters the heat exchanger 7 through the high-pressure compressor outlet pipe 15 and the heat exchanger inlet pipe 16. After heat exchange, it enters the external transmission network through the external transmission main pipe 17.

[0048] After the gas in the gas chamber has been delivered, the high-pressure vaporization self-pressurization process is activated. The steps of this process are as follows:

[0049] S1, the liquid outlet control valve 33 on the lower discharge pipe 24 of the liquid chamber and the first gasification transfer tank inlet control valve 34 on the first gasification transfer tank inlet pipe 25 above the first gasification transfer tank 3 are opened, and the liquid medium enters the gasification transfer tank 3 through the liquid phase external transmission main pipe 11 and the first gasification transfer tank inlet pipe 25 above the first gasification transfer tank 3. At this time, the heat exchange section 5 of the gasification transfer tank 3 is not working, and the gasification transfer tank 3 maintains a low pressure P1.

[0050] S2, after the liquid fills the first gasification transfer tank 3, close the gas supply control valve 35 of the first gasification transfer tank, and start the heat exchange unit 5 to gasify and pressurize the liquid in the first gasification transfer tank 3.

[0051] S3, synchronously, open the second gasification transfer tank inlet control valve 38 above the second gasification transfer tank 4 to perform the feeding operation.

[0052] S4. After the pressure of the first gasification transfer tank 3 increases to P2, open the gas transmission control valve 35 of the first gasification transfer tank above the first gasification transfer tank 3 and the gas collection pipeline control valve 36 on the gas collection pipeline in the station, and transport the saturated gas through the gas transmission pipeline 26 of the first gasification transfer tank and the gas collection main pipe 12 to the ground heating device 41.

[0053] S5, the gas is heated by the ground heater 41 and then enters the external transmission network through the external transmission main 17.

[0054] S6. After the first gasification transfer tank 3 has finished discharging, open the first gasification transfer tank exhaust valve 39 to discharge the remaining high-pressure gas into the gas chamber, so as to help the first gasification transfer tank 3 reduce the pressure to the inlet pressure.

[0055] S7, after the first gasification transfer tank 3 is completely emptied, the feeding operation S1 is restarted.

[0056] S8, the second gasification transfer tank 4 continues the operations of S2 to S4.

[0057] This cycle is repeated to achieve continuous gasification and external transportation.

[0058] In some embodiments, the cryogenic energy medium includes, but is not limited to, LNG, liquid hydrogen, LPG, etc.

[0059] The liquid chamber and air chamber are arranged with a liquid chamber in the middle and air chambers on both sides.

[0060] The gasification transfer tank is located on a plane lower than the storage section, and the liquid chamber adopts a bottom discharge method.

[0061] In some embodiments, the liquid chamber is also provided with a gas chamber inlet pipe 19 for backup when there is a high demand for storage space.

[0062] In some embodiments, when the total number of storage chambers is set to 7 to 10, preferably, the number of gas chambers is 2 to 3, which can better couple the injection and collection days.

[0063] In some embodiments, the operating pressure P1 of the storage unit is 0.03 to 1.2 MPa.

[0064] In some embodiments, the external pressure P2 is 4 to 10 MPa.

[0065] In some embodiments, the pressure of the vaporization transfer tank is slightly higher than the pressure of the external transmission pipeline during vaporization and external transmission.

[0066] In some embodiments, the switching interval between the two gasification transfer tanks is 1 to 8 hours, and the capacity of a single tank is 1000 to 6000 m³. 3 .

[0067] In some embodiments, the vaporization temperature of the medium is controlled between -180 and -100°C.

[0068] In some embodiments, the heat load of the gasification heating section is 15 to 30 MW.

[0069] In some embodiments, a storage, gasification, and gas extraction unit, apparatus, and method for a cryogenic energy underground gas storage facility are provided. This provides a complete liquid injection and gas extraction process for new cryogenic energy underground liquid storage by utilizing elevation difference, gravity-assisted liquid transfer, and natural heat source gasification pressurization and external transmission, making full use of environmental resources and effectively reducing power equipment configuration and operating costs.

[0070] The system includes: liquid injection section, storage section, transfer gasification self-pressurization section, and high-pressure gas extraction section.

[0071] Liquid injection part

[0072] In some embodiments, the liquid injection section of the storage and extraction device of the cryogenic energy underground gas storage facility includes a vertical liquid injection pipe 9 and a liquid phase unloading main pipe 10. Cryogenic liquid is injected into the storage section from the liquid cargo tank of a tank truck or ship through the liquid phase unloading pipe by means of a pump and gravity.

[0073] A cooling coil is installed on the outside of the vertical injection pipe 9 to keep the vertical injection pipe 9 undercooled by means of a low-temperature medium, so as to prevent the low-temperature energy medium from directly vaporizing during the unloading process.

[0074] Storage Department

[0075] In some embodiments, the storage section of the storage and extraction device of the cryogenic energy underground gas storage facility includes multiple liquid storage chambers and gas chambers. The liquid chambers are used to store liquid, and the gas chambers are used to store the evaporated gas from the liquid chambers during the injection period (without external output). They are arranged and connected in a proportional orientation.

[0076] To ensure the stability of the surrounding temperature field, the liquid cavity and gas cavity are arranged with the liquid cavity in the middle and the gas cavities on both sides.

[0077] The ratio of liquid chamber to gas chamber is rationally configured based on the injection and production cycle, market demand, storage conditions, and medium density characteristics to ensure that the gas chamber can accommodate all the evaporated gas from liquid chamber 2 during periods without external transmission.

[0078] Both the liquid chamber 2 and the gas chamber are connected to the main discharge pipe via inlet pipes above the storage tank, allowing liquid to enter the chambers. Under normal operating conditions, only the liquid chamber is discharged; the gas chamber inlet pipe is only opened in emergency situations.

[0079] Under normal conditions, the liquid chamber and the gas chamber are connected by an exhaust pipe above the liquid chamber, a low-pressure gas phase pipe, and an intake pipe above the gas chamber, and the valves on the pipes are kept open to ensure that the evaporated gas in the liquid chamber can fill the intake gas phase space in a timely manner.

[0080] A bypass is installed in the air inlet pipe of the air chamber. When the pressure in one air chamber exceeds the set value, exhaust gas is discharged to the air chamber with lower pressure to equalize the pressure.

[0081] Safety valves are installed in the liquid chamber and the gas chamber respectively for releasing overpressure within the chamber.

[0082] Air supply valves are installed in the liquid chamber and the gas chamber respectively for low-pressure air supply in the chamber.

[0083] The liquid chamber 2 is designed to be at least 5°C lower than the minimum temperature of the medium so that the liquid can be stored stably.

[0084] Under the influence of the temperature field, the temperature of the gas cavity will reach the saturation temperature of the medium.

[0085] An outlet pipe is installed at the lower part of liquid chamber 2 and connected to the liquid phase external transmission main pipe.

[0086] High-pressure gas extraction unit

[0087] The high-pressure gas extraction unit includes a high-pressure compressor 6 and a heat exchanger 7. When there is an external transmission requirement, the gas in the gas chamber is first extracted through the exhaust pipe of the high-pressure compressor 6 and then through the high-pressure compressor inlet main pipe. After heat exchange in the heat exchanger 7, the gas reaches the external transmission temperature requirement and then enters the external transmission pipeline.

[0088] The setting of the heat exchanger 41 is determined according to the temperature requirements of the exported gas.

[0089] Transit gasification self-pressurization unit

[0090] The transfer gasification self-pressurization unit includes at least two gasification transfer tanks that can operate alternately and corresponding heat exchange units.

[0091] The switching interval of the gasification transfer tank can be determined according to the actual operating frequency.

[0092] The capacity of the gasification transfer tank is determined based on the switching interval and the capacity of the external transmission pipeline.

[0093] The upper part is equipped with an inlet pipe and an inlet control valve, which are connected to the liquid phase external transmission main pipe.

[0094] The upper part is equipped with a gas transmission pipeline and a gas transmission control valve, which are connected to the main gas extraction pipeline.

[0095] The upper part is equipped with an exhaust pipe and an exhaust control valve, which is connected to the gas connection main pipe of the storage area so as to discharge high-pressure gas into the low-pressure gas chamber and realize the pressure reduction of the gasification transfer tank.

[0096] The transshipment self-pressurizing vaporization section is installed at a lower plane than the storage section, and the liquid chamber adopts a bottom-out liquid method. Its advantage is that it facilitates the liquid to flow into the vaporization section by gravity.

[0097] The heat exchange section can be an electric heat tracing section or a heat exchange section that utilizes natural heat sources, such as a geothermal utilization section, in order to reduce energy consumption.

[0098] The vaporization pressure in the vaporization transfer tank is slightly higher than the pressure in the main export pipeline in order to lift the gas to the ground export section.

[0099] When the heat exchanger efficiency is high enough to meet the external temperature requirements, the process of using a heat exchanger for supplemental heating can be omitted, such as... Figure 2 As shown, this is to ensure the efficient and intensive use of heat sources.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A storage and extraction device for a cryogenic underground gas storage facility, characterized in that, include: The liquid injection section includes a vertical liquid injection pipe and a liquid phase unloading main pipe. Cryogenic liquid is sequentially injected from the liquid cargo tank into the vertical liquid injection pipe and the liquid phase unloading main pipe. The storage section is connected to the liquid phase unloading main pipe. The storage section includes multiple liquid chambers and gas chambers. The liquid chambers are used to store liquid, and the gas chambers are used to store the evaporated gas from the liquid chambers during the liquid injection period. A transfer gasification self-pressurization unit, wherein the storage unit is connected to the transfer gasification self-pressurization unit, the transfer gasification self-pressurization unit comprising at least two gasification transfer tanks capable of alternating operation and corresponding heat exchange units; and The high-pressure gas collection unit includes a high-pressure compressor and a heat exchanger. When there is an external transmission requirement, the gas in the gas chamber is first extracted through the gas chamber exhaust pipe and the high-pressure compressor inlet main pipe by the high-pressure compressor. After heat exchange by the heat exchanger to reach the external transmission temperature requirement, it enters the external transmission pipeline. The storage unit is arranged with a liquid chamber in the middle and gas chambers on both sides. The configuration is reasonable according to the injection and production cycle, market demand, storage conditions and medium density characteristics. This ensures that the gas chambers can accommodate all the evaporated gas from the liquid chambers during periods when there is no external output. Both the liquid chambers and gas chambers are connected to the liquid phase unloading main pipe through the feed pipe above the storage tank so that the liquid can enter the chambers. Under normal conditions, the liquid chamber and gas chamber are connected by the liquid chamber exhaust pipe above the liquid chamber, the gas connection main pipe, and the gas chamber inlet pipe above the gas chamber, with the valves on the pipes kept open to ensure that the evaporated gas in the liquid chamber can fill the gas phase space in time. A bypass is set in the gas chamber inlet pipe of the gas chamber. When the pressure in one gas chamber exceeds the set value, the gas is exhausted to the lower pressure gas chamber to equalize the pressure. Safety valves are set in the liquid chamber and gas chamber respectively for overpressure relief in the chamber. Gas replenishment valves are set in the liquid chamber and gas chamber respectively for low-pressure gas replenishment in the chamber. The switching interval of the gasification transfer tank in the transfer gasification self-pressurization unit is determined according to the operating frequency. The tank capacity of the gasification transfer tank is determined according to the switching interval and the capacity of the external transmission pipeline. The transfer gasification self-pressurization unit is equipped with a liquid inlet pipe and a liquid inlet control valve, which are connected to the liquid phase external transmission main pipe. It is also equipped with a gas transmission pipe and a gas transmission control valve, which are connected to the gas collection main pipe. Furthermore, it is equipped with an exhaust pipe and an exhaust control valve, which are connected to the gas connection main pipe of the storage area, so as to discharge high-pressure gas into the low-pressure gas chamber and realize the pressure reduction of the gasification transfer tank.

2. The storage and extraction device for a cryogenic energy underground gas storage facility according to claim 1, characterized in that, A cooling coil is installed on the outside of the vertical injection pipe of the injection section. The vertical injection pipe is kept undercooled by the help of a low-temperature medium to prevent the low-temperature energy medium from directly vaporizing during the unloading process.

3. The storage and extraction device for a cryogenic energy underground gas storage facility according to claim 1, characterized in that, The high-pressure gas extraction unit also includes a heat replenisher installed on the main gas extraction pipe, which is set according to the temperature requirements of the exported gas.

4. The storage and extraction device for a cryogenic energy underground gas storage facility according to claim 1, characterized in that, The installation plane of the transfer vaporization self-pressurization unit is lower than that of the storage unit. The liquid chamber adopts a bottom-out liquid method, which facilitates the liquid to automatically flow into the transfer vaporization self-pressurization unit under the action of gravity. Furthermore, the vaporization pressure of the vaporization transfer tank is slightly higher than that of the external transmission main pipe, so as to lift the gas to the ground external transmission unit.

5. A method for storing and extracting cryogenic underground gas in a cryogenic energy storage facility, using the storage and extraction device for cryogenic underground gas storage according to any one of claims 1-4, characterized in that: During unloading, cryogenic energy from tank trucks or transport ships is injected into the liquid chamber of the storage section by means of pumps and gravity through vertical injection pipes, liquid phase unloading main pipes, and liquid chamber inlet pipes above the liquid chamber. When there is no external output during static storage, the liquid chamber and the gas chamber are connected through the liquid chamber exhaust pipe above the liquid chamber, the gas connection main pipe and the gas chamber inlet pipe above the gas chamber. The evaporated gas in the liquid chamber enters the first gas chamber for accumulation and storage under the action of pressure difference and density difference. A bypass is set in the gas chamber inlet pipe of the first gas chamber. When the pressure on one side is higher, the gas is discharged into the other low-pressure gas chambers through the gas connection main pipe. When exporting, start the high-pressure compressor process. After the gas in the gas chamber has been transported, start the high-pressure vaporization self-pressurization process.

6. The storage and extraction method for a cryogenic energy underground gas storage facility according to claim 5, characterized in that, The high-pressure compressor process includes: using the high-pressure compressor, the low-pressure gas in the first gas chamber is extracted through the gas chamber exhaust pipe above the gas chamber and the high-pressure compressor inlet main pipe, and then enters the heat exchanger through the high-pressure compressor outlet pipe and the heat exchanger inlet pipe for heat exchange, and then enters the external transmission network through the external transmission main pipe.

7. The storage and extraction method for a cryogenic energy underground gas storage facility according to claim 5, characterized in that, The high-pressure gasification self-pressurization process includes: S1, the liquid medium enters the gasification transfer tank through the liquid phase external transmission main pipe and the liquid inlet pipe above the gasification transfer tank. At this time, the heat exchange section of the gasification transfer tank does not work, and the tank is kept at low pressure P1. S2. After the liquid fills the vaporization and transfer tank, close its inlet valve and start the heat exchange unit to vaporize and pressurize the liquid in the tank. S3, Simultaneously, open the liquid inlet valve above another gasification transfer tank to perform the feeding operation; S4. After the pressure in the gasification transfer tank increases to P2, open the gas transmission valve above and the pressure regulating valve on the gas collection pipeline in the station to transport the saturated gas through the pipeline to the ground heating device. S5, the gas is heated to the required temperature for external transmission by the ground heating device and then enters the external transmission network through the external transmission main; S6. After the gasification transfer tank has finished its external output, open its exhaust valve to discharge the residual high-pressure gas into the gas chamber, so as to help the gasification transfer tank reduce the pressure to the inlet pressure. S7, after one of the gasification transfer tanks is completely emptied, the feeding operation step S1 is restarted; S8, another gasification transfer tank continues to perform the operations of steps S2 to S4, and so on to achieve continuous gasification and external output; The gasification pressure in the gasification transfer tank is slightly higher than that in the main export pipeline, so as to lift the gas to the ground export system.

Images