Low-pressure gas storage pressure stabilizing device and compressed carbon dioxide energy storage system

Abstract

The present application relates to the technical field of physical energy storage, and provides a low-pressure gas storage pressure stabilizing device and a compressed carbon dioxide energy storage system, wherein the low-pressure gas storage pressure stabilizing device comprises a gas storage tank, an elastic air bag and a gas pressure adjusting module; the gas storage tank is provided with a gas inlet and a gas outlet; the elastic air bag is provided with a gas pressure adjusting inlet and a gas pressure adjusting outlet, and is arranged in the gas storage tank to separate an inner cavity of the gas storage tank into a balance cavity and a gas storage cavity which are independent of each other; the gas inlet and the gas outlet are both communicated with the gas storage cavity, and the gas pressure adjusting inlet and the gas pressure adjusting outlet are both communicated with the balance cavity; the gas pressure adjusting module is communicated with the gas pressure adjusting inlet and the gas pressure adjusting outlet, and is used for controlling the volume change of the balance cavity through the gas pressure adjusting inlet and the gas pressure adjusting outlet. The present application can overcome the defects of the carbon dioxide energy storage system in the prior art, and can also make the unit realize dynamic balance under variable working conditions, thereby ensuring the stable operation of the system.

Description

Technical Field

[0001] This invention relates to the field of physical energy storage technology, and in particular to a low-pressure gas storage and stabilization device and a compressed carbon dioxide energy storage system. Background Technology

[0002] Compressed carbon dioxide energy storage refers to the use of surplus electricity from the power grid during off-peak hours or electricity from sources with drastic fluctuations such as wind and solar power to compress carbon dioxide. The compressed high-pressure carbon dioxide is then liquefied and stored in a gas storage device. When needed, the liquefied carbon dioxide is released and vaporized to drive an air turbine to generate electricity.

[0003] In existing compressed carbon dioxide energy storage system designs, the carbon dioxide storage device is generally a fixed-volume type. According to the gas law, during the venting process of a fixed-volume pressure vessel, the gas pressure inside the vessel continuously decreases due to the reduction in gas volume. Because of this continuous pressure decrease during the venting process of a fixed-volume compressed air storage device, the carbon dioxide compressor will experience a certain degree of pressure slippage during operation, even with a certain pressure on the low-pressure side. Summary of the Invention

[0004] This invention provides a low-pressure gas storage and stabilizing device and a compressed carbon dioxide energy storage system to solve the defect of sliding pressure in the operation of existing carbon dioxide energy storage systems. It overcomes the defect of sliding pressure operation in existing carbon dioxide energy storage systems, and enables the unit to achieve dynamic balance under varying operating conditions, ensuring stable system operation.

[0005] This invention provides a low-pressure gas storage and stabilization device, comprising:

[0006] A gas storage tank, the gas storage tank having an air inlet and an air outlet;

[0007] An elastic airbag, having a pressure regulating inlet and a pressure regulating outlet, is disposed within a gas storage tank to divide the inner cavity of the gas storage tank into an independent balance chamber and a storage chamber. The air inlet and the air outlet are both connected to the storage chamber, and the pressure regulating inlet and the pressure regulating outlet are both connected to the balance chamber.

[0008] A pressure regulating module is connected to both the pressure regulating inlet and the pressure regulating outlet. The pressure regulating module is used to control the volume change of the balance chamber through the pressure regulating inlet and the pressure regulating outlet.

[0009] According to a low-pressure gas storage and stabilizing device provided by the present invention, the gas storage tank and the elastic airbag are arranged coaxially, and the gas storage tank is provided with an air inlet and an air outlet at two opposite ends arranged along its axis. The air pressure regulating inlet and the air pressure regulating outlet are respectively connected to the outside of the gas storage tank through the air inlet and the air outlet.

[0010] According to a low-pressure gas storage and stabilizing device provided by the present invention, the gas pressure regulating module includes an inlet regulating component and an outlet regulating component. The inlet regulating component is connected to the gas pressure regulating inlet and is used to control the gas flow rate of the gas pressure regulating inlet according to the gas pressure change at the outlet. The outlet regulating component is connected to the gas pressure regulating outlet and is used to control the gas flow rate of the gas pressure regulating outlet according to the gas pressure change at the inlet.

[0011] According to a low-pressure gas storage and stabilizing device provided by the present invention, the air intake regulating component includes a one-way valve and an air compressor. The air compressor is connected to the air pressure regulating inlet through the one-way valve, and the air compressor is used to provide compressed gas to the balance chamber.

[0012] According to a low-pressure gas storage and stabilizing device provided by the present invention, the low-pressure gas storage and stabilizing device further includes a buffer tank, which is connected to the gas pressure regulating inlet and the gas pressure regulating outlet.

[0013] According to a low-pressure gas storage and stabilizing device provided by the present invention, the gas outlet regulating component includes an electric regulating valve, which is used to regulate the opening degree of the gas pressure regulating outlet.

[0014] According to a low-pressure gas storage and stabilizing device provided by the present invention, the gas storage tank includes an outer shell and an inner shell, the inner shell is disposed inside the outer shell, the outer shell and the inner shell are provided with a heat insulation layer spaced apart, and the elastic airbag is disposed inside the inner shell.

[0015] According to a low-pressure gas storage and stabilizing device provided by the present invention, the low-pressure gas storage and stabilizing device further includes a flange connection assembly. The gas pressure regulating inlet and the gas pressure regulating outlet are connected to the air inlet and the air outlet through the flange connection assembly. The flange connection assembly includes a first fixed flange cover, a connecting knot, and a second fixed flange cover. The first fixed flange cover is disposed inside the elastic air bladder and is correspondingly arranged with the gas pressure regulating inlet and the gas pressure regulating outlet. The second fixed flange cover is connected to the air inlet pipe or the air outlet pipe. The connecting knot is connected between the first fixed flange cover and the second fixed flange cover.

[0016] According to a low-pressure gas storage and stabilizing device provided by the present invention, the low-pressure gas storage and stabilizing device further includes a first temperature and pressure gauge and a second temperature and pressure gauge. The first temperature and pressure gauge is disposed on the gas storage tank and is used to detect the temperature and pressure of the gas storage chamber. The second temperature and pressure gauge is connected to the buffer tank and is used to detect the temperature and pressure of the balance chamber.

[0017] The present invention also provides a compressed carbon dioxide energy storage system, comprising the aforementioned low-pressure gas storage and stabilization device, liquid carbon dioxide storage tank, energy storage unit, power generation unit, heat storage unit, and cold storage unit. The low-pressure gas storage and stabilization device includes a gas storage tank, an elastic airbag, and a pressure regulating component. The gas storage tank has an inlet and an outlet. The elastic airbag has a pressure regulating inlet and a pressure regulating outlet. The elastic airbag is disposed within the gas storage tank to divide the inner cavity of the gas storage tank into an independent balance chamber and a storage chamber. The inlet and outlet are both connected to the storage chamber, and the pressure regulating inlet and outlet are both connected to the balance chamber. The pressure regulating module is connected to both the pressure regulating inlet and outlet, and is used to control the volume change of the balance chamber through the pressure regulating inlet and outlet. The gas storage tank and the liquid carbon dioxide storage tank are connected by energy storage pipelines and energy release pipelines to form a closed-loop circuit. The energy storage unit is located in the energy storage pipeline and is used to compress and store the carbon dioxide in the energy storage pipeline before sending it to the liquid carbon dioxide storage tank. The power generation unit is located in the energy release pipeline and is used to generate electricity using the energy released from the carbon dioxide in the energy release pipeline. The heat storage unit is connected to the energy storage pipeline and the energy release pipeline and is used to store the heat generated by the energy storage unit and apply it to the energy release pipeline. The cold storage unit is connected to the energy storage pipeline and the energy release pipeline and is used to store the cold energy generated by the power generation unit and apply it to the energy storage pipeline.

[0018] This invention provides a low-pressure gas storage and stabilizing device. An elastic airbag is installed inside the gas storage tank, dividing the tank's interior into an independent balance chamber and a storage chamber. Both the air inlet and outlet are connected to the storage chamber, while the pressure regulating inlet and outlet are connected to the balance chamber. When the outlet is in the outlet position, the amount of carbon dioxide gas in the storage chamber decreases. At this time, the pressure regulating module controls the pressure regulating inlet to open, introducing gas into the balance chamber to increase its volume, thus increasing the pressure of the elastic airbag. The bladder compresses the volume of the gas storage chamber through elastic deformation to ensure the pressure of the gas storage chamber. When the air inlet is in the intake state, the amount of carbon dioxide gas in the gas storage chamber gradually increases. At this time, the pressure regulating module controls the opening of the pressure regulating outlet. As the gas is discharged from the balance chamber, the pressure in the balance chamber decreases. The elastic bladder compresses the balance chamber through elastic deformation to maintain the pressure stability of the gas storage chamber. In this way, the gas storage chamber is in a dynamic pressure stabilization state, preventing the occurrence of sliding pressure operation in the carbon dioxide energy storage system, enabling the unit to achieve stability under varying operating conditions, and ensuring the stable operation of the system. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a connection diagram of the compressed carbon dioxide energy storage system provided by the present invention;

[0021] Figure 2 yes Figure 1 A partial enlarged view of the pressure regulating inlet of the medium and low pressure gas storage and stabilizing device.

[0022] Figure label:

[0023] 100. Low-pressure gas storage and stabilizing device;

[0024] 110. Gas tank; 111. Air inlet; 112. Air outlet; 113. Air inlet interface; 114. Air outlet interface; 115. Gas storage chamber; 116. Outer shell; 117. Inner shell; 118. Insulation layer;

[0025] 120. Elastic airbag; 121. Balance chamber; 122. Air pressure regulating inlet; 123. Air pressure regulating outlet;

[0026] 130. Intake regulating assembly; 131. One-way valve; 132. Air compressor;

[0027] 140. Exhaust air regulating assembly; 141. Electric regulating valve;

[0028] 150. Buffer tank;

[0029] 160. Flange connection assembly; 161. First fixed flange cover; 162. Connecting joint; 163. Second fixed flange cover;

[0030] 170. First temperature and pressure gauge;

[0031] 180. Second temperature and pressure gauge;

[0032] 10. Compressed carbon dioxide energy storage system;

[0033] 200. Liquid carbon dioxide storage tank; 300. Energy storage pipeline; 400. Energy release pipeline; 500. Compressor; 600. Expander; 700. Heat accumulator; 800. Cold accumulator. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0035] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0037] This invention proposes a low-pressure gas storage and stabilization device and a compressed carbon dioxide energy storage system.

[0038] In the embodiments of the invention, reference is made to... Figures 1 to 2 The low-pressure gas storage and stabilizing device 100 includes a gas storage tank 110, an elastic airbag 120, and a pressure regulating module. The gas storage tank 110 has an air inlet 111 and an air outlet 112. The elastic airbag 120 has a pressure regulating inlet 122 and a pressure regulating outlet 123. The elastic airbag 120 is disposed inside the gas storage tank 110 to divide the inner cavity of the gas storage tank 110 into an independent balance chamber 121 and a gas storage chamber 115. The air inlet 111 and the air outlet 112 are both connected to the gas storage chamber 115. The pressure regulating inlet 122 and the pressure regulating outlet 123 are both connected to the balance chamber 121. The pressure regulating module is connected to both the pressure regulating inlet 122 and the pressure regulating outlet 123. The pressure regulating module is used to control the volume change of the balance chamber 121 through the pressure regulating inlet 122 and the pressure regulating outlet 123.

[0039] Specifically, in this embodiment of the invention, the low-pressure gas storage and stabilizing device 100 includes a gas storage tank 110, an elastic airbag 120, and a pressure regulating module. The gas storage tank 110 is a container for storing carbon dioxide gas, having an inlet 111 and an outlet 112 to allow gas to enter and exit. The gas storage tank 110 can be made of different materials (such as steel or plastic) and has different capacities to meet different application requirements. The elastic airbag 120 is made of flexible material and has certain pressure resistance, tear resistance, and low leakage rate. The elastic airbag 120 is an inflatable and deflated membrane or bag-like structure. The elastic airbag 120 has a pressure regulating inlet 122 and a pressure regulating outlet 123 for allowing pressure regulation. When the elastic airbag 120 inflates, it occupies a portion of the space in the gas storage tank 110, dividing the inner cavity of the tank into two independent balancing chambers 121 and a storage chamber 115. The balancing chamber 121 primarily regulates air pressure, while the storage chamber 115 stores carbon dioxide. The elastic airbag 120 can be replaced with other types of cavity structures, such as pistons or diaphragms, to achieve the functions of dividing the internal cavities of the gas storage tank 110 and controlling pressure. The air pressure regulating module controls the air pressure regulating inlet 122 and the air pressure regulating outlet 123, thereby controlling the volume change of the balancing chamber 121. Specifically, the volume of the balancing chamber 121 can increase or decrease, controlled according to the air pressure changes in the storage chamber. The system can be operated automatically or manually, controlling the volume of the balancing chamber 121 through the air pressure regulating inlet 122 and the air pressure regulating outlet 123 to stabilize the air pressure in the storage chamber 115.

[0040] This invention provides a low-pressure gas storage and stabilizing device 100. An elastic airbag 120 is installed inside a gas storage tank 110, which divides the inner cavity of the gas storage tank 110 into an independent balance chamber 121 and a storage chamber 115. An air inlet 111 and an air outlet 112 are both connected to the storage chamber 115, while a pressure regulating inlet 122 and a pressure regulating outlet 123 are both connected to the balance chamber 121. When the air outlet 112 is discharging gas, the amount of carbon dioxide gas in the storage chamber 115 decreases. At this time, the pressure regulating module controls the pressure regulating inlet 122 to open, thereby increasing the volume of the balance chamber 121 by introducing gas into it. The elastic airbag 120 compresses the volume of the gas storage chamber 115 through elastic deformation to ensure the pressure of the gas storage chamber 115. When the air inlet 111 is in the air intake position, the amount of carbon dioxide gas in the gas storage chamber 115 gradually increases. At this time, the pressure regulating module controls the opening of the pressure regulating outlet 123. As the gas is discharged from the balance chamber 121, the pressure in the balance chamber 121 decreases. The elastic airbag 120 compresses the balance chamber 121 through elastic deformation to maintain the pressure stability of the gas storage chamber 115. In this way, the gas storage chamber 115 is in a dynamic pressure stabilization state, preventing the occurrence of sliding pressure operation of the carbon dioxide energy storage system, enabling the unit to achieve stability under varying operating conditions, and ensuring the stable operation of the system.

[0041] Reference Figure 1 In one embodiment, the gas storage tank 110 and the elastic airbag 120 are coaxially arranged. The gas storage tank 110 has an inlet port 113 and an outlet port 114 at opposite ends along its axis. The pressure regulating inlet 122 and the pressure regulating outlet 123 are respectively connected to the outside of the gas storage tank 110 through the inlet port 113 and the outlet port 114. It can be understood that this embodiment separates the inflation and deflation of the airbag by setting the gas flow path at both ends of the axis, avoiding mutual interference and improving the convenience and accuracy of pressure regulation. At the same time, the arrangement of the inlet port 113 and the outlet port 114 facilitates the connection between the elastic airbag 120 and the gas storage tank 110.

[0042] Reference Figure 1In one embodiment, the air pressure regulating module includes an inlet regulating component 130 and an outlet regulating component 140. The inlet regulating component 130 is connected to the air pressure regulating inlet 122 and is used to control the air flow rate of the air pressure regulating inlet 122 according to the air pressure change at the outlet 112. The outlet regulating component 140 is connected to the air pressure regulating outlet 123 and is used to control the air flow rate of the air pressure regulating outlet 123 according to the air pressure change at the inlet 111. In this embodiment, the inlet regulating component 130 and the outlet regulating component 140 control the air flow rate of the air pressure regulating inlet 122 and the air flow rate of the air pressure regulating outlet 123, respectively, thereby controlling the change in the volume of the balance chamber 121, and thus controlling the change in the proportion of the balance chamber 121 and the air storage chamber 115 in the air storage tank 110, so as to regulate the air pressure in the air storage chamber 115. When the air pressure at the outlet 112 is high, the intake regulating component 130 reduces the air flow rate at the pressure regulating inlet 122, thereby limiting the intake volume and reducing the air pressure. Conversely, when the air pressure at the inlet 111 is high, the outlet regulating component 140 reduces the air flow rate at the pressure regulating outlet 123, thereby limiting the output volume and increasing the air pressure.

[0043] Reference Figure 1 In one embodiment, the intake regulating assembly 130 includes a one-way valve 131 and an air compressor 132. The air compressor 132 is connected to the air pressure regulating inlet 122 via the one-way valve 131 and is used to supply compressed gas to the balance chamber 121. It is understood that the intake regulating assembly 130 can use either an air compressor 132 or a blower, depending on the carbon dioxide gas pressure required by the system. This application uses an air compressor 132 as an example; other embodiments can be implemented with reference to this embodiment. The one-way valve 131 is located between the air compressor 132 and the air pressure regulating inlet 122, allowing airflow to pass in one direction. The air compressor 132 is used to compress external air or carbon dioxide and blow it into the balance chamber 121. The air compressor 132 can adjust the compression rate of the air according to changes in the air pressure at the outlet 112 to achieve air pressure balance in the air storage chamber 115.

[0044] Reference Figure 1In one embodiment, the low-pressure gas storage and stabilizing device 100 further includes a buffer tank 150, which is connected to the pressure regulating inlet 122 and the pressure regulating outlet 123. It is understood that this embodiment uses the buffer tank 150 to share the burden of balancing gas pressure in the balancing chamber 121. When the pressure at the pressure regulating inlet 122 is high, excess gas enters the buffer tank 150, thereby reducing the pressure of the pressure regulating system. Conversely, when the pressure at the pressure regulating outlet 123 is low, gas in the buffer tank 150 flows to the outlet, increasing the pressure of the pressure regulating system. Thus, the buffer tank 150 helps balance the gas pressure, enabling the pressure regulating system to operate more stably.

[0045] Reference Figure 1 In one embodiment, the gas outlet regulating assembly 140 includes an electrically operated regulating valve 141, which is used to regulate the opening degree of the gas pressure regulating outlet 123. It is understood that by adjusting the opening degree of the electrically operated regulating valve 141, the amount of gas flowing out of the gas pressure regulating outlet 123 can be precisely controlled, thereby achieving gas pressure regulation. The electrically operated regulating valve 141 features rapid response and precise control, and can adjust the pressure of the gas pressure regulating outlet 123 in real time according to system requirements.

[0046] Reference Figure 1 and Figure 2 In one embodiment, the gas storage tank 110 includes an outer shell 116 and an inner shell 117. The inner shell 117 is located inside the outer shell 116, and an insulation layer 118 is spaced between the outer shell 116 and the inner shell 117. An elastic airbag 120 is disposed within the inner shell 117. It is understood that the outer shell 116 is the external structure of the gas storage tank 110, used to enclose the internal components and provide protection. The inner shell 117 is located inside the outer shell 116 and serves as a container for the internal gas. The insulation layer 118 is provided between the inner shell 117 and the outer shell 116 to isolate the influence of the external ambient temperature on the internal gas of the gas storage tank 110 and reduce heat transfer. The insulation layer 118 can be made of heat-insulating materials, such as polystyrene board, to provide good insulation performance.

[0047] Reference Figure 1 and Figure 2In one embodiment, the low-pressure gas storage and stabilizing device 100 further includes a flange connection assembly 160. The pressure regulating inlet 122 and pressure regulating outlet 123 are connected to the inlet port 113 and outlet port 114 via the flange connection assembly 160. The flange connection assembly 160 includes a first fixed flange cover 161, a connecting knot 162, and a second fixed flange cover 163. The first fixed flange cover 161 is located inside the elastic air bladder 120 and corresponds to the pressure regulating inlet 122 and pressure regulating outlet 123. The second fixed flange cover 163 is connected to the inlet pipe or outlet pipe. The connecting knot 162 is connected between the first fixed flange cover 161 and the second fixed flange cover 163. It is understood that the first fixed flange cover 161 is located inside the elastic air bladder 120 and corresponds to the pressure regulating inlet 122 and pressure regulating outlet 123 to provide fixation and sealing, ensuring the stability of the connection. The second fixed flange cover 163 is connected to the inlet or outlet pipe for introducing or discharging gas into or out of the gas storage system. The connecting knot 162 is a short pipe with flanges on both sides. Before the elastic airbag 120 is installed on the gas storage tank 110, the connecting knot 162 is connected to the elastic airbag 120. The connecting knot 162 facilitates installation and disassembly.

[0048] Reference Figure 1 In one embodiment, the low-pressure gas storage and stabilizing device 100 further includes a first temperature and pressure gauge 170 and a second temperature and pressure gauge 180. The first temperature and pressure gauge 170 is mounted on the gas storage tank 110 and is used to detect the temperature and pressure of the gas storage chamber 115. The second temperature and pressure gauge 180 is connected to the buffer tank 150 and is used to detect the temperature and pressure of the balance chamber 121. It is understood that the first temperature and pressure gauge 170, mounted on the gas storage tank 110, is used to detect the temperature and pressure of the gas storage chamber 115 to provide real-time information about the gas state inside the gas storage chamber 115. By monitoring the temperature and pressure of the gas storage chamber 115, the volume of the balance chamber 121 can be controlled to achieve dynamic pressure balance during gas inlet or outlet. The second temperature and pressure gauge 180 is connected to the connecting pipeline between the buffer tank 150 and the pressure regulating inlet 122 and the pressure regulating outlet 123, and is used to detect the temperature and pressure of the balance chamber 121. The balancing chamber 121 is typically used to balance the pressure stability of the gas storage chamber 115, thereby enhancing system stability. The second temperature and pressure gauge 180 provides information on the gas state within the balancing chamber 121, allowing the gas outlet or flow rate to be adjusted promptly via the pressure regulating module to control the pressure stability of the gas storage chamber 115. Thus, by setting up the first and second temperature and pressure gauges 170 and 180, the temperature and pressure of the gas storage chamber 115 and the balancing chamber 121 can be effectively monitored, providing real-time operating status information to support the safe control and operation of the system.

[0049] The present invention also proposes a compressed carbon dioxide energy storage system 10, which includes a low-pressure gas storage and stabilizing device 100. The specific structure of the low-pressure gas storage and stabilizing device 100 is as described in the above embodiments. Since this smoke machine adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0050] Specifically, the compressed carbon dioxide energy storage system 10 also includes a liquid carbon dioxide storage tank 200, an energy storage unit, a power generation unit, a heat storage unit, and a cold storage unit. The gas storage tank 110 and the liquid carbon dioxide storage tank 200 are connected through an energy storage pipeline 300 and an energy release pipeline 400 to form a closed-loop circuit. The energy storage unit is located in the energy storage pipeline 300 and is used to compress and store the carbon dioxide in the energy storage pipeline 300 before passing it to the liquid carbon dioxide storage tank 200. The power generation unit is located in the energy release pipeline 400 and is used to generate electricity using the energy released from the carbon dioxide in the energy release pipeline 400. The heat storage unit is connected to the energy storage pipeline 300 and the energy release pipeline 400 and is used to store the heat generated by the energy storage unit and apply it to the energy release pipeline 400. The cold storage unit is connected to the energy storage pipeline 300 and the energy release pipeline 400 and is used to store the cold energy generated by the power generation unit and apply it to the energy storage pipeline 300. The energy storage unit includes a compressor 500, the power generation unit includes an expander 600, the heat storage unit includes a cold storage tank, the cold storage unit includes a cold storage tank, the air inlet 111 is connected to the expander 600 through the energy release pipeline 400, and the air outlet 112 is connected to the compressor 500 through the energy storage pipeline 300.

[0051] Charging process: Low-pressure carbon dioxide in the low-pressure gas storage container enters the compressor 500, and the amount of carbon dioxide gas in the gas storage chamber 115 decreases. At this time, the one-way valve 131 opens, the air compressor 132 starts, and air enters the balance chamber 121 of the elastic air bag 120 through the air compressor 132. Then, through the feedback control between the second temperature and pressure gauge 180 and the air compressor 132, the pressure of carbon dioxide in the gas storage chamber 115 is kept constant until the charging process is over.

[0052] Discharge process: Low-pressure carbon dioxide enters the gas storage chamber 115 from the outlet of the expander 600. The amount of gas in the gas storage chamber 115 increases continuously. At this time, the opening of the electric regulating valve 141 is adjusted to regulate the air pressure in the balance chamber 121 and maintain the pressure of carbon dioxide in the gas storage chamber 115.

[0053] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0054] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0055] 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 low-pressure gas storage pressure stabilizing device, characterized by comprising: The low-pressure gas storage and pressure stabilizing device comprises: a gas storage tank having a gas inlet and a gas outlet; an elastic gas bag having a gas pressure adjusting inlet and a gas pressure adjusting outlet, the elastic gas bag being arranged in the gas storage tank to divide an inner cavity of the gas storage tank into a balance cavity and a gas storage cavity which are independent of each other, the gas inlet and the gas outlet being in communication with the gas storage cavity, and the gas pressure adjusting inlet and the gas pressure adjusting outlet being in communication with the balance cavity; and a gas pressure adjusting module in communication with the gas pressure adjusting inlet and the gas pressure adjusting outlet, the gas pressure adjusting module being used to control the volume change of the balance cavity through the gas pressure adjusting inlet and the gas pressure adjusting outlet. The gas storage tank and the elastic gas bag are coaxially arranged, the gas storage tank is provided with a gas inlet interface and a gas outlet interface at two opposite ends along the axis of the gas storage tank, so that the path of gas flow is arranged along the two ends of the axis, and the gas pressure adjusting inlet and the gas pressure adjusting outlet are in communication with the outside of the gas storage tank through the gas inlet interface and the gas outlet interface respectively. The gas pressure adjusting module comprises a gas inlet adjusting assembly and a gas outlet adjusting assembly, the gas inlet adjusting assembly is in communication with the gas pressure adjusting inlet and is used to control the gas flow of the gas pressure adjusting inlet according to the gas pressure change of the gas outlet, and the gas outlet adjusting assembly is in communication with the gas pressure adjusting outlet and is used to control the gas flow of the gas pressure adjusting outlet according to the gas pressure change of the gas inlet. The gas storage tank comprises an outer shell and an inner shell, the inner shell is arranged inside the outer shell, and a heat preservation layer is arranged between the outer shell and the inner shell, and the elastic gas bag is arranged in the inner shell. The low-pressure gas storage and pressure stabilizing device further comprises a flange connection assembly, the gas pressure adjusting inlet and the gas pressure adjusting outlet are connected to the gas inlet interface and the gas outlet interface through the flange connection assembly. The gas inlet adjusting assembly comprises a one-way valve and an air compressor, the air compressor is connected to the gas pressure adjusting inlet through the one-way valve, and the air compressor is used to provide compressed gas to the balance cavity.

2. The low-pressure gas storage pressure stabilizing device according to claim 1, characterized by The low-pressure gas storage and pressure stabilizing device further comprises a buffer tank, the buffer tank is in communication with the gas pressure adjusting inlet and the gas pressure adjusting outlet.

3. The low-pressure gas storage pressure stabilizing device according to claim 2, characterized by The gas outlet adjusting assembly comprises an electric regulating valve, the electric regulating valve is used to adjust the opening degree of the gas pressure adjusting outlet.

4. The low-pressure gas storage pressure stabilizing device according to claim 1, wherein The flange connection assembly comprises a first fixed flange cover, a connecting slipknot and a second fixed flange cover, the first fixed flange cover is arranged in the elastic gas bag and is arranged correspondingly to the gas pressure adjusting inlet and the gas pressure adjusting outlet, the second fixed flange cover is connected to a gas inlet pipeline or a gas outlet pipeline, and the connecting slipknot is connected between the first fixed flange cover and the second fixed flange cover.

5. The low-pressure gas storage pressure stabilizing device according to claim 1, wherein The low-pressure gas storage and pressure stabilizing device further comprises a first temperature and pressure gauge and a second temperature and pressure gauge, the first temperature and pressure gauge is arranged on the gas storage tank and is used to detect the temperature and pressure of the gas storage cavity, and the second temperature and pressure gauge is connected to the buffer tank and is used to detect the temperature and pressure of the balance cavity.

6. The low-pressure gas storage pressure stabilizing device according to claim 3, wherein ​ 7. A compressed carbon dioxide energy storage system, characterized by, The low-pressure gas storage pressure stabilizing device according to any one of claims 1 to 6; and a liquid carbon dioxide storage tank, the gas storage tank and the liquid carbon dioxide storage tank being connected through an energy storage pipeline and an energy release pipeline to form a closed circulation loop; an energy storage unit arranged in the energy storage pipeline, the energy storage unit being used to compress and store energy of carbon dioxide in the energy storage pipeline and then pass the carbon dioxide to the liquid carbon dioxide storage tank; a power generation unit arranged in the energy release pipeline, the power generation unit being used to generate power from energy released by carbon dioxide in the energy release pipeline; a heat storage unit connected to the energy storage pipeline and the energy release pipeline, the heat storage unit being used to store heat generated by the energy storage unit and act on the energy release pipeline; a cold storage unit connected to the energy storage pipeline and the energy release pipeline, the cold storage unit being used to store cold generated by the power generation unit and act on the energy storage pipeline.

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