Pipelined energy storage device and control method thereof

Abstract

This invention discloses a pipeline energy storage device and its control method, relating to the field of energy storage technology. It includes a pipeline pressurization system and a storage tank. The pipeline pressurization system's input end is connected to a raw material inlet and inputs initial-state raw material gas; its output end is connected to a delivery pipeline and outputs supercritical-state raw material gas. The storage tank stores the raw material gas and is connected to an energy storage loop and an energy release loop. The energy storage loop compresses and cools the gaseous raw material gas output from the storage tank into a liquid state, then depressurizes it and returns it to the storage tank. The energy release loop pressurizes and heats the liquid raw material gas output from the storage tank to a supercritical state; a portion is input into the delivery pipeline, and the other portion is heated and expanded into a gaseous state, which is then input into the storage tank along with the compressed raw material gas input to the raw material inlet. This achieves the effect of maintaining the continuity of carbon dioxide pipeline transportation and reducing the electricity cost of supercritical carbon dioxide pipeline transportation.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to a pipeline energy storage device and its control method. Background Technology

[0002] Carbon capture, utilization, and storage (CFS) is a large-scale carbon dioxide emission reduction pathway aimed at addressing global climate change and an important measure for achieving sustainable development for human society. Carbon dioxide transport is a key link in the CFS industry chain, connecting carbon dioxide capture with carbon dioxide utilization or storage.

[0003] The cost of carbon dioxide transportation is one of the major factors that directly affects the economics of carbon capture, utilization and storage projects. In particular, large-scale, long-distance supercritical carbon dioxide pipeline transportation not only requires investment in pipelines, compressor stations and other infrastructure, but also incurs the cost of a large amount of electricity required to compress carbon dioxide at atmospheric or low pressure to above critical pressure during operation. The electricity cost of the compression process accounts for a high proportion of the total cost of transporting each ton of carbon dioxide, sometimes even more than half. Summary of the Invention

[0004] The purpose of this invention is to provide a pipeline energy storage device and its control method, which can maintain the continuity of carbon dioxide pipeline transportation and reduce the electricity cost of supercritical carbon dioxide pipeline transportation.

[0005] The above-mentioned technical objective of the present invention is achieved through the following technical solution:

[0006] A pipeline-transported energy storage device includes a pipeline pressurization system and a storage tank.

[0007] The pipeline pressurization system has an input end connected to the raw material inlet and inputs the initial state of raw material gas, and an output end connected to the conveying pipeline and outputs the supercritical state of raw material gas. The storage tank stores the raw material gas and is connected to the energy storage circuit and the energy release circuit. The energy storage circuit compresses and cools the gaseous raw material gas output from the storage tank into a liquid state, and then depressurizes it and sends it back to the storage tank.

[0008] The energy release circuit pressurizes and heats the liquid raw material gas output from the storage tank to a supercritical state. Part of it is input into the delivery pipeline, and the other part is heated and expanded into a gaseous state, which is then input into the storage tank together with the raw material gas that is compressed again after being input into the raw material inlet.

[0009] Furthermore, the storage tank includes a gaseous space and a liquid space, with the gaseous space connected to a first inlet and outlet, and the liquid space connected to a second inlet and outlet.

[0010] Furthermore, the storage tank also includes a solid space, where raw material gas containing gas, liquid, and solid coexistes is stored.

[0011] Furthermore, it also includes heat storage modules and cold storage modules, which exchange heat with the energy storage loop and the energy release loop through heat exchangers.

[0012] Furthermore, the heat storage module includes a first cold tank and a first hot tank, wherein the first cold tank is used to store a heat storage medium at room temperature and the first hot tank is used to store a heat storage medium at high temperature.

[0013] The cold storage module includes a second cold tank and a second hot tank. The second cold tank is used to store low-temperature cold storage medium, and the second hot tank is used to store cold storage medium at room temperature.

[0014] Furthermore, the energy release circuit includes an expander and a second compressor. The expander expands the raw material gas output from the storage tank, and the second compressor is connected to the raw material inlet and compresses the initial state of the raw material gas therein. The expander drives the second compressor to work.

[0015] Furthermore, the energy storage circuit includes a first compressor connected to the first inlet and outlet of the storage tank. The output end of the first compressor is connected to a first heat exchanger, and heat is transferred to the heat storage module through the first heat exchanger. The other end of the first heat exchanger is connected to a condenser, and the other end of the condenser is connected to a subcooler. The subcooler further cools the raw gas through the cold storage capacity of the cold storage module. The other end of the subcooler is connected to an expansion mechanism, and the output end of the expansion mechanism is connected to the second inlet and outlet of the storage tank.

[0016] Furthermore, the energy release circuit includes a booster pump connected to the second inlet and outlet of the storage tank. The other end of the booster pump is connected to the second heat exchanger. The liquid raw material gas output by the booster pump transfers the cooling energy to the cold storage module. The other end of the second heat exchanger is connected to the first circuit and the second circuit. The first circuit is connected to the delivery pipeline, and the second circuit is connected to the third heat exchanger. The raw material gas in the second circuit absorbs the heat stored in the cold storage module through the third heat exchanger and simultaneously absorbs the heat of compression of the raw material gas output by the second compressor through the third heat exchanger. The other end of the third heat exchanger is connected to the expander. The exhaust gas from the expander and the raw material gas output from the third heat exchanger are input into the second heat exchanger together and absorb the cooling energy from the liquid raw material gas output by the booster pump to cool down. Finally, the gas is input into the storage tank.

[0017] The present invention also discloses a control method, comprising the following steps:

[0018] Under the energy storage process mode,

[0019] The pipeline pressurization system operates, pressurizing the initial raw material gas to a supercritical state before inputting it into the pipeline. Simultaneously, the energy release circuit is stopped, and the energy storage circuit is activated. The energy storage circuit compresses and cools the gaseous raw material gas output from the storage tank into a liquid state, then depressurizes it and returns it to the storage tank. At the same time, the liquid raw material gas in the storage tank is converted into a solid state. In the energy storage process mode, the pipeline energy storage device operates at high power, and the power consumption includes the operation of the pipeline pressurization system and the compression of the gaseous raw material gas.

[0020] Under the energy release process mode,

[0021] The pipeline pressurization system stops; simultaneously, the energy storage circuit stops and the energy release circuit operates, pressurizing and heating the liquid raw material gas output from the storage tank to a supercritical state. Part of it is input into the delivery pipeline, and the other part is heated and expanded into a gaseous state, which is then input into the storage tank along with the raw material gas that has been compressed again at the raw material inlet. At the same time, it exchanges heat with the solid raw material gas in the storage tank and together they are converted into a liquid state. In the energy release process mode, the pipeline delivery energy storage device operates at low power, and the power consumption is used for pressurizing the liquid raw material gas.

[0022] Furthermore, the feed gas is carbon dioxide. The pipeline pressurization system pressurizes the initial feed gas to a supercritical state before it is fed into the delivery pipeline.

[0023] In summary, the present invention has the following beneficial effects:

[0024] The pipeline energy storage device and its control method provided by this invention are combined with the time-of-use pricing of the power grid to control the operation of the energy storage circuit during off-peak hours and the operation of the energy release circuit during peak hours, thereby realizing the off-peak operation of the pipeline booster system and saving electricity costs; or they can be combined with new energy sources to control the operation of the energy storage circuit during periods of abundant new energy power generation and the operation of the energy release circuit during periods of insufficient new energy power, thereby realizing the coordinated operation of the pipeline booster system and new energy sources and reducing or avoiding the curtailment of new energy power.

[0025] The pipeline energy storage device and its control method of the present invention fully recover waste heat and waste cold to improve energy efficiency and have high energy storage round-trip efficiency; its energy storage process and energy release process directly use carbon dioxide from the carbon dioxide transportation system as the working medium, which is completely compatible with the carbon dioxide transportation system, and carbon dioxide is a natural working medium, which makes the pipeline energy storage device inherently safe; its equipment is mature and reliable, and its service life can reach the same long service life as the carbon dioxide transportation system. Attached Figure Description

[0026] Figure 1 This is a process flow diagram of a pipeline energy storage device according to the present invention.

[0027] In the diagram, 1 is the storage tank; 2 is the first compressor; 3 is the first heat exchanger; 4 is the condenser; 5 is the subcooler; 6 is the expansion mechanism; 7 is the booster pump; 8 is the second heat exchanger; 9 is the third heat exchanger; 10 is the expander; 11 is the second compressor; 12 is the first cold tank; 13 is the first hot tank; 14 is the second hot tank; and 15 is the second cold tank. Detailed Implementation

[0028] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. These embodiments do not constitute a limitation of the present invention. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this application.

[0029] A pipeline energy storage device, such as Figure 1 As shown, it includes a pipeline pressurization system, storage tank 1, a heat storage module, and a cold storage module.

[0030] The pipeline pressurization system has an input end connected to the raw material inlet via a valve to input the initial state of raw material gas, and an output end connected to the delivery pipeline via a valve to output the supercritical state of raw material gas. Storage tank 1 stores the raw material gas and is connected to the energy storage circuit and the energy release circuit. The energy storage circuit compresses and cools the gaseous raw material gas output from storage tank 1 into a liquid state, and then depressurizes it before sending it back to storage tank 1.

[0031] The energy release circuit pressurizes and heats the liquid raw material gas output from storage tank 1 to a supercritical state. Part of it is input into the delivery pipeline, and the other part is heated and expanded into a gaseous state, and is input into storage tank 1 together with the raw material gas that is compressed again after being input into the raw material inlet.

[0032] Among them, the heat storage module and the cold storage module exchange heat with the energy storage circuit and the energy release circuit through heat exchangers.

[0033] like Figure 1 As shown, the raw material gas is carbon dioxide. Storage tank 1 is used to store carbon dioxide. The carbon dioxide in storage tank 1 is in a thermodynamic state point where gas, liquid and solid coexist. It stores raw material gas in gas, liquid and solid coexistence, including gas space, liquid space and solid space. As carbon dioxide is converted and input and output, the size of the three spaces changes accordingly. The upper gas space of storage tank 1 is connected to the first inlet and outlet, and the middle liquid space (below the liquid surface) is connected to the second inlet and outlet.

[0034] like Figure 1 As shown, specifically, the energy storage circuit includes a first compressor 2, the inlet of which is connected to the first inlet and outlet of the storage tank 1, for compressing the gaseous carbon dioxide output from the storage tank 1 to near the critical pressure.

[0035] The output end of the first compressor 2 is connected to the first heat exchanger 3, and the heat is transferred to the heat storage module through the first heat exchanger 3; the inlet of the carbon dioxide side of the first heat exchanger 3 is connected to the outlet of the first compressor 2, and is used to transfer the heat of the carbon dioxide to the heat storage medium on the other side.

[0036] The other end of the first heat exchanger 3 is connected to the condenser 4; the inlet of the condenser 4 is connected to the outlet on the carbon dioxide side of the first heat exchanger 3, which is used to cool the carbon dioxide into liquid by utilizing the environment.

[0037] The other end of the condenser 4 is connected to the subcooler 5; the inlet of the subcooler 5 is connected to the outlet of the condenser 4, and the subcooler 5 further reduces the temperature of the liquid carbon dioxide by utilizing the cold storage capacity of the cold storage module (heat exchange is achieved through heat exchangers, etc.).

[0038] The other end of the subcooler 5 is connected to the expansion mechanism 6. The inlet of the expansion mechanism 6 is connected to the outlet of the subcooler 5, and the output end is connected to the second inlet and outlet of the storage tank 1. It is used to depressurize carbon dioxide and input it into the second inlet and outlet of the storage tank 1. A throttling device or a pressure energy recovery device can be used.

[0039] like Figure 1 As shown, specifically, the energy release circuit includes a booster pump 7, the inlet of which is connected to the second inlet and outlet of the storage tank 1, for pressurizing liquid carbon dioxide to a high pressure state above the critical pressure.

[0040] The other end of the booster pump 7 is connected to the second heat exchanger 8. The liquid raw material gas output by the booster pump 7 transfers the cooling capacity to the cold storage module. In this embodiment, the inlet of the high-pressure carbon dioxide side of the second heat exchanger 8 is connected to the outlet of the booster pump 7, which is used to transfer the cooling capacity of the high-pressure carbon dioxide to the carbon dioxide on the low-pressure carbon dioxide side and to the heat storage medium on the cold storage medium side.

[0041] The other end of the second heat exchanger 8 (the outlet on the high-pressure carbon dioxide side) is connected to the first and second loops, splitting the supercritical carbon dioxide output from the high-pressure carbon dioxide side of the second heat exchanger 8 into two streams for separate delivery.

[0042] The first loop is connected to the inlet of the delivery pipeline via a valve, allowing one stream of supercritical carbon dioxide to be delivered into the delivery pipeline;

[0043] The second loop is connected to the third heat exchanger 9. The raw material gas in the second loop absorbs the heat storage heat of the heat storage module through the third heat exchanger 9. In this embodiment, the inlet of the supercritical carbon dioxide side of the third heat exchanger 9 is connected to the outlet of the high-pressure carbon dioxide side of the second heat exchanger 8, and absorbs heat from the heat storage medium on the heat storage medium side and the carbon dioxide on the low-pressure carbon dioxide side (the compression heat of the raw material gas output by the second compressor 11).

[0044] The other end of the third heat exchanger 9 (the outlet on the supercritical carbon dioxide side) is connected to the expander 10. The expander 10 expands the raw material gas (liquid raw material gas from the storage tank 1, heated to supercritical carbon dioxide). The inlet of the expander 10 is connected to the outlet on the supercritical carbon dioxide side of the third heat exchanger 9, which is used to expand the supercritical carbon dioxide to do work and convert the carbon dioxide into a low-pressure gaseous state.

[0045] like Figure 1As shown, the exhaust gas from the expander 10, along with the raw material gas that has been compressed and heat-exchanged after entering the raw material inlet, is fed into the storage tank 1. In this embodiment, a second compressor 11 is provided in the energy release circuit. The second compressor 11 is connected to the raw material inlet through a valve, and the raw material gas in its initial carbon dioxide state is input and compressed to increase its pressure. It is then transported to the low-pressure carbon dioxide side of the third heat exchanger 9 to release heat. After merging with the low-pressure carbon dioxide output from the expander 10, it is input into the inlet of the low-pressure carbon dioxide side of the second heat exchanger 8, and then input into the first inlet and outlet of the storage tank 1 from the outlet of the low-pressure carbon dioxide side of the second heat exchanger 8. In this embodiment, the second compressor 11 is connected to the expander 10 through a transmission mechanism, and the expander 10 drives the second compressor 11.

[0046] like Figure 1 As shown, the heat storage module includes a first cold tank 12 and a first hot tank 13. The first cold tank 12 is used to store a heat storage medium at room temperature (such as water or heat transfer oil), and the first hot tank 13 is used to store a heat storage medium at high temperature. The outlet of the first cold tank 12 is connected to the inlet of the heat storage medium side of the first heat exchanger 3, and the inlet of the first cold tank 12 is connected to the outlet of the heat storage medium side of the third heat exchanger 9. The inlet of the first hot tank 13 is connected to the outlet of the heat storage medium side of the first heat exchanger 3, and the outlet of the first hot tank 13 is connected to the inlet of the heat storage medium side of the third heat exchanger 9.

[0047] The cold storage module includes a second cold tank 15 and a second hot tank 14. The second cold tank 15 is used to store low-temperature cold storage media (such as brine solution or ethylene glycol solution), and the second hot tank 14 is used to store cold storage media at room temperature. The outlet of the second cold tank 15 is connected to the inlet of the cold storage medium side of the subcooler 5, and the inlet of the second cold tank 15 is connected to the outlet of the cold storage medium side of the second heat exchanger 8. The inlet of the second hot tank 14 is connected to the outlet of the cold storage medium side of the subcooler 5, and the outlet of the second hot tank 14 is connected to the inlet of the cold storage medium side of the second heat exchanger 8.

[0048] In some embodiments, the pipeline energy storage device also includes a control module for switching and controlling the operation of the pipeline energy storage device and the carbon dioxide pipeline pressurization system; in addition, it also includes pipelines, valves, instruments, circuits and other auxiliary facilities.

[0049] The present invention also discloses a control method, which is applied to the above-mentioned pipeline energy storage device through a control module, comprising the following steps:

[0050] Under the energy storage process mode,

[0051] When the pipeline pressurization system is in operation, it pressurizes the initial raw material gas to a supercritical state and then inputs it into the delivery pipeline. At the same time, it controls the energy release circuit to stop and the energy storage circuit to operate. The energy storage circuit compresses and cools the gaseous raw material gas output from storage tank 1 into a liquid state, and then depressurizes it and inputs it back into storage tank 1. Meanwhile, the liquid raw material gas in storage tank 1 is converted into a solid state.

[0052] In the energy storage process mode, the energy storage device operates at high power, mainly including the power consumption of the pipeline pressurization system and the power consumption of the first compressor 2 (compression of gaseous raw material gas).

[0053] Under the energy release process mode,

[0054] The pipeline pressurization system stops; at the same time, the energy storage circuit stops and the energy release circuit operates, pressurizing and heating the liquid raw material gas in storage tank 1 to a supercritical state. Part of it is input into the delivery pipeline, and the other part is heated and expanded into a gaseous state. It is then input into storage tank 1 together with the raw material gas that is compressed again after entering the raw material inlet. At the same time, it is converted into a liquid state after exchanging heat with the solid raw material gas in storage tank 1.

[0055] In the energy release process mode, the energy storage device operates at low power, mainly due to the power consumption of the booster pump 7 (pressurization of liquid raw material gas).

[0056] Specifically,

[0057] When electricity consumption occurs during periods of low electricity prices, the control module switches to the energy storage process mode; the control pipeline pressurization system is in operation, pressurizing the initial ambient temperature and pressure raw material gas to a supercritical state of 9MPa / 35℃, and inputting it into the delivery pipeline; simultaneously, the control energy release circuit is in a stopped state, and the control energy storage circuit is in an operating state; the control first compressor 2 is in operation, and the first compressor 2, driven by electricity, compresses the gaseous carbon dioxide output from storage tank 1 to a high pressure of 8MPa, and then the first heat exchanger 3 transfers the heat of compression to the heat storage medium (which flows from the first cold tank 12 into the first hot tank 13), cooling the carbon dioxide to 40℃, and then the condenser 4 liquefies the carbon dioxide to 30℃, and then the subcooler 5 transfers the heat to the cold storage medium (which flows from the second cold tank 15 into the second hot tank 14), further cooling the carbon dioxide to a low temperature of -40℃, and then the expansion mechanism 6 depressurizes it before inputting it into storage tank 1; through the operation of the energy storage circuit, the liquid carbon dioxide in storage tank 1 is transformed into a solid state;

[0058] When electricity consumption occurs during periods of high electricity prices, the control module switches to the energy release process mode; the control pipeline pressurization system is stopped, and simultaneously, the control energy storage circuit is stopped while the control energy release circuit is running; the control booster pump 7 is operated, and under electric drive, the booster pump 7 pressurizes the liquid carbon dioxide output from storage tank 1 to a pressure of 9 MPa. Then, the second heat exchanger 8 transfers the cooling capacity of the liquid carbon dioxide to the gaseous carbon dioxide side and the cold storage medium (the cold storage medium flows from the second hot tank 14 into the second cold tank 15), causing the carbon dioxide to heat to a supercritical state of 9 MPa / 35℃. The supercritical carbon dioxide is then divided into two streams, one of which is input into the delivery pipeline (flow rate according to...). According to the transport requirements), another stream is input into the third heat exchanger 9 and heated by the heat storage medium (which flows from the first hot tank 13 into the first cold tank 12) together with the carbon dioxide on the gaseous carbon dioxide side. Then, it is expanded by the expander 10 to do work and is depressurized to 0.6MPa and cooled. At the same time, the second compressor 11, driven by the expander 10, compresses the initial raw material gas to 0.6MPa. Then, it releases the heat of compression through the third heat exchanger 9 (the gaseous carbon dioxide input side), and then merges with the exhaust gas of the expander 10. Finally, it is cooled to a low temperature by the second heat exchanger 8 (the gaseous carbon dioxide input side) and input into the storage tank 1. Through the operation of the energy release circuit, the solid carbon dioxide in the storage tank 1 is converted into liquid.

[0059] The control method provided in this invention can adopt energy storage and energy release processes according to the time distribution of low and high electricity prices. The operation of the pipeline pressurization system can avoid the high electricity price period, maintain the continuity of carbon dioxide pipeline transportation, and not affect the stable operation of the upstream carbon dioxide capture process, thereby achieving the effects of saving electricity costs, assisting the power grid in peak shaving and valley filling, and helping to promote the consumption of new energy.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within the scope of its essence and protection. Such modifications or equivalent substitutions should also be considered to fall within the protection scope of the present invention.

Claims

1. A pipeline energy storage device, characterized by: Including pipeline pressurization systems and storage tanks, The pipeline pressurization system has an input end connected to the raw material inlet and inputs the initial state of raw material gas, and an output end connected to the conveying pipeline and outputs the supercritical state of raw material gas. The storage tank stores the raw material gas and is connected to the energy storage circuit and the energy release circuit. The energy storage circuit compresses and cools the gaseous raw material gas output from the storage tank into a liquid state, and then depressurizes it and sends it back to the storage tank. The energy release circuit pressurizes and heats the liquid raw material gas output from the storage tank to a supercritical state. Part of it is input into the delivery pipeline, and the other part is heated and expanded into a gaseous state, and then input into the storage tank together with the raw material gas that is compressed again after being input into the raw material inlet. Under the energy storage process mode, The pipeline pressurization system operates, pressurizing the initial raw material gas to a supercritical state before inputting it into the pipeline. Simultaneously, the energy release circuit is stopped, and the energy storage circuit is activated. The energy storage circuit compresses and cools the gaseous raw material gas output from the storage tank into a liquid state, then depressurizes it and returns it to the storage tank. At the same time, the liquid raw material gas in the storage tank is converted into a solid state. In the energy storage process mode, the pipeline energy storage device operates at high power, and the power consumption includes the operation of the pipeline pressurization system and the compression of the gaseous raw material gas. Under the energy release process mode, The pipeline pressurization system stops; simultaneously, the energy storage circuit stops and the energy release circuit operates, pressurizing and heating the liquid feed gas output from the storage tank to a supercritical state. Part of it is input into the delivery pipeline, and the other part is heated and expanded into a gaseous state, which is then input into the storage tank along with the feed gas that has been compressed again at the feed inlet. At the same time, it exchanges heat with the solid feed gas in the storage tank and together they are converted into a liquid state. In the energy release process mode, the pipeline delivery energy storage device operates at low power, and the power consumption is used for pressurizing the liquid feed gas. The feed gas is carbon dioxide. The pipeline pressurization system pressurizes the initial feed gas to a supercritical state before it is fed into the delivery pipeline.

2. The pipeline energy storage device according to claim 1, characterized in that: The storage tank includes a gaseous space and a liquid space, with the gaseous space connected to a first inlet and outlet, and the liquid space connected to a second inlet and outlet.

3. The pipeline energy storage device according to claim 2, characterized in that: The storage tank also includes a solid space, where raw material gas containing gas, liquid, and solid coexistes.

4. The pipeline energy storage device according to claim 2, characterized in that: It also includes a heat storage module and a cold storage module, which exchange heat with the energy storage circuit and the energy release circuit through a heat exchanger.

5. The pipeline energy storage device according to claim 4, characterized in that: The heat storage module includes a first cold tank and a first hot tank. The first cold tank is used to store a heat storage medium at room temperature, and the first hot tank is used to store a heat storage medium at high temperature. The cold storage module includes a second cold tank and a second hot tank. The second cold tank is used to store low-temperature cold storage medium, and the second hot tank is used to store cold storage medium at room temperature.

6. The pipeline energy storage device according to claim 1, characterized in that: The energy release circuit includes an expander and a second compressor. The expander expands the raw material gas output from the storage tank, and the second compressor is connected to the raw material inlet and compresses the initial state of the raw material gas therein. The expander drives the second compressor to work.

7. The pipeline energy storage device according to claim 4, characterized in that: The energy storage circuit includes a first compressor connected to the first inlet and outlet of the storage tank. The output end of the first compressor is connected to a first heat exchanger, and heat is transferred to the heat storage module through the first heat exchanger. The other end of the first heat exchanger is connected to a condenser, and the other end of the condenser is connected to a subcooler. The subcooler further cools the raw gas through the cold storage capacity of the cold storage module. The other end of the subcooler is connected to an expansion mechanism, and the output end of the expansion mechanism is connected to the second inlet and outlet of the storage tank.

8. A pipeline energy storage device according to claim 4 or 7, characterized in that: The energy release circuit includes a booster pump connected to the second inlet and outlet of the storage tank. The other end of the booster pump is connected to the second heat exchanger. The liquid raw material gas output by the booster pump transfers the cooling energy to the cold storage module. The other end of the second heat exchanger is connected to the first circuit and the second circuit. The first circuit is connected to the delivery pipeline, and the second circuit is connected to the third heat exchanger. The raw material gas in the second circuit absorbs the heat stored in the cold storage module and the heat of compression of the raw material gas output by the second compressor through the third heat exchanger. The other end of the third heat exchanger is connected to the expander. The exhaust gas from the expander and the raw material gas output from the third heat exchanger are input into the second heat exchanger and cooled down by absorbing the cooling energy from the liquid raw material gas output by the booster pump. Finally, the gas is input into the storage tank.

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