Thermocline energy storage container and compressed air energy storage system

Abstract

The utility model relates to the technical field of compressed air energy storage systems and related equipment, in particular to a thermocline energy storage container which comprises a container body, a diaphragm and a heat insulation plate, one side of the heat insulation plate is attached to the outer surface of the diaphragm, the diaphragm divides the container body into a first cavity and a second cavity, and the container body is of a horizontal structure. A piston mechanism is arranged in the container body and comprises a piston rod and a cylinder body, and the piston rod is rigidly connected with the other side of the heat insulation plate. According to the thermocline energy storage container, in the operation process of a compressed air energy storage system, it is guaranteed that the heat insulation plate is attached to the diaphragm through pushing and pulling of the piston mechanism, the heat insulation plate is prevented from being overturned, and therefore it is guaranteed that heat exchange of one kind of gas or liquid at different temperatures in a space with the constant volume is reduced.

Description

Technical Field

[0001] This utility model relates to the technical field of energy storage systems and related equipment, specifically to a temperature-controlled energy storage container and a compressed air energy storage system. Background Technology

[0002] Compressed air energy storage technology refers to an energy storage method that uses electrical energy to compress air during periods of low grid load and releases the compressed air to drive power generation during periods of high grid load. The container for storing the gas is the key to compressed air energy storage technology. Existing constant pressure systems require isobaric heating of the medium inside the container to induce volume changes and meet the constant pressure requirement. During this process, the temperature of the medium to be exchanged within the container changes, and the resulting dynamic changes are difficult to control. To address this, researchers have added insulation devices to isolate the diaphragm from heat exchange, which effectively blocks heat exchange. However, this relies on the weight of the insulation device for balance and is only suitable for vertical containers. When applied to horizontal containers, the insulation device poses a risk of tipping over during movement, requiring further improvement. Summary of the Invention

[0003] One of the technical problems to be solved by this application is to overcome the defects of the above-mentioned related technologies and provide a sloped-temperature energy storage container and a compressed air energy storage system. The sloped-temperature energy storage container can reduce the heat exchange between a gas or liquid at different temperatures in a space with a constant volume.

[0004] The technical solution adopted by the inclined temperature energy storage container to solve the technical problem is as follows: an inclined temperature energy storage container includes a container body, a diaphragm and a heat insulation plate. The diaphragm divides the container body into a first cavity and a second cavity. One side of the heat insulation plate is attached to the diaphragm. The container body has a horizontal structure. A piston mechanism is provided inside the first cavity of the container body. The piston mechanism includes a piston rod and a cylinder. The piston rod is rigidly connected to the other side of the heat insulation plate.

[0005] Compared with related technologies, the inclined temperature energy storage container body with piston-type heat insulation structure has the following advantages:

[0006] 1. Dynamic pressure balance and high stability: Through the linkage design of piston mechanism and heat insulation plate, the diaphragm moves in real time with the change of working fluid volume, automatically compensating for pressure fluctuations; during energy storage (gas filling) and energy release (gas exhaust) processes, the pressure inside the container body remains constant (e.g. 1.5MPa), without relying on external pressure regulating equipment, significantly improving the system's operational stability.

[0007] 2. High-efficiency insulation and reduced energy loss: The insulation board and the diaphragm only contact each other at the smallest plane, achieving physical and thermal isolation between the working fluids.

[0008] 3. Compact structure and simplified system integration: The horizontal container body and piston are integrated into one design, eliminating the need for traditional complex external transmission mechanisms, reducing equipment size, and facilitating underground installation or applications in space-constrained scenarios. Through the working fluid circulation and pressure linkage between the two container bodies, the overall pressure and temperature of the energy storage system are automatically balanced, reducing reliance on pump and valve components.

[0009] 4. Enhanced Safety: Redundant pressure relief and sealing; in the event of diaphragm rupture, the piston mechanism limits the working fluid mixing range; multi-layered sealing structure provides dual protection. This avoids the risk of diaphragm rupture due to pressure imbalance and meets industrial safety standards.

[0010] Preferably, the cylinders are nested structures, with the outer cylinder fixedly connected to the container body, and the inner cylinder fitted inside the outer cylinder and slidingly engaged with it. The piston is limited to sliding within the inner cylinder. This design allows the piston to slide freely inside the inner cylinder, and the inner cylinder to slide freely within the outer cylinder. The two-stage cylinder design increases the piston rod stroke, which in turn increases the sliding distance of the heat insulation plate, thereby increasing the diaphragm's contraction range. This, in turn, increases the volume change of the first chamber and the volume change of the second chamber, significantly improving energy storage.

[0011] Preferably, the first chamber is used to store air, and the second chamber is used to store carbon dioxide. This allows the inclined temperature energy storage container to effectively separate and store different types of gases, thereby improving the efficiency and safety of the entire system.

[0012] Preferably, the diaphragm has a multi-layer composite structure, including a middle pressure-resistant layer and two heat-insulating layers on both sides. The pressure-resistant layer ensures the stability and reliability of the diaphragm under high-pressure environments, while the heat-insulating layers effectively reduce heat transfer, thereby maintaining a stable temperature inside the cavity.

[0013] The technical solution adopted by this compressed air energy storage system to solve the technical problem is as follows: the first chamber of the inclined temperature energy storage container is connected to the energy storage tanks of the air compression energy storage subsystem and the air expansion energy release subsystem, and the second chamber of the inclined temperature energy storage container is connected to the carbon dioxide gas-liquid conversion subsystem. This makes the carbon dioxide gas-liquid conversion process more efficient and stable, thereby improving the energy conversion efficiency of the entire system.

[0014] Preferably, the energy storage tank includes a tank body, inside which a diaphragm divides the tank into a liquid chamber and a gas chamber. The gas chamber is connected to a second chamber, and the liquid chamber is connected to the second chamber via a circulating pump and a heat exchanger. This allows for effective control of the temperature and pressure of carbon dioxide during the gas-liquid conversion process.

[0015] Preferably, the diaphragm of the tank is equipped with a heat insulation plate, which is slidably connected to the tank body. This not only ensures the heat insulation effect, but also makes it easy to maintain and replace the tank when needed, improving the maintainability and service life of the system. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the inclined temperature energy storage container of this utility model;

[0017] Figure 2 This is a structural schematic diagram of the compressed air energy storage system of this utility model (the air compression energy storage subsystem and the air expansion generator system are omitted);

[0018] Figure 3 This is a cross-sectional view of the energy storage tank of the carbon dioxide gas-liquid conversion subsystem of the compressed air energy storage system of this utility model.

[0019] Reference numerals: 1. Inclined temperature energy storage container; 11. Container body; 12. Diaphragm; 121. Contact surface; 13. First cavity; 14. Second cavity; 15. Insulation plate; 16. Piston mechanism; 21. Tank body; 22. Gas-liquid separation membrane; 221. Contact surface; 23. Liquid cavity; 24. Gas cavity; 25. Insulation plate. Detailed Implementation

[0020] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of this application and are not intended to limit the scope of protection of the embodiments of this application. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0022] This preferred embodiment is as follows: Figure 1 The inclined temperature energy storage container 1 shown includes a container body 11, a diaphragm 12 and a heat insulation plate 15. The diaphragm 12 divides the container body 11 into a first cavity 13 and a second cavity 14. One side of the heat insulation plate 15 is attached to the outer surface of the diaphragm 12. The container body 11 has a horizontal structure. A piston mechanism 16 is provided in the first cavity 13 of the container body 11. The piston mechanism 16 includes a piston rod and a cylinder. The piston rod is rigidly connected to the other side of the heat insulation plate 15.

[0023] As an improvement, the cylinders are nested structures. The outer cylinder is fixedly connected to the container body 11, and the inner cylinder is fitted inside the outer cylinder and slides with it. The piston is limited to sliding within the inner cylinder. This design allows the piston to slide freely inside the inner cylinder, and the inner cylinder to slide freely within the outer cylinder. The two-stage cylinder design increases the piston rod stroke from about half of the original total length to about two-thirds of the total length, which increases the sliding distance of the heat insulation plate 15. This increases the contraction range of the diaphragm 12, which in turn increases the volume change of the first chamber 13 and the second chamber 14, thereby significantly improving energy storage.

[0024] As an improvement, the diaphragm 12 has a multi-layer composite structure, including a pressure-resistant layer in the middle and heat-insulating layers on both sides. The pressure-resistant layer ensures the stability and reliability of the diaphragm 12 under high pressure, while the heat-insulating layers on both sides effectively reduce heat transfer between the second cavity 14 and the diaphragm 12, and between the diaphragm 12 and the heat insulation plate 15, thereby maintaining the temperature stability inside the second cavity 14.

[0025] The inclined temperature energy storage container 1 is applied to, for example... Figure 2 In the compressed air energy storage system shown (the air compression energy storage subsystem and the air expansion power generation system are omitted as they are not modified): the first chamber 13 is used to store air, and the second chamber 14 is used to store carbon dioxide. The two media are physically separated by a heat insulation plate 15 and a diaphragm 12. The contact surface 121 where the diaphragm 12 and the heat insulation plate 15 are attached has only one side, and the area of ​​the contact surface 121 is close to the vertical cross-section of the container, thus having the smallest area. That is, during the expansion or contraction of the diaphragm 12, it always ensures that the side with the smallest area is the contact surface 121 for heat exchange between the two different media.

[0026] In the carbon dioxide gas-liquid conversion subsystem of a compressed air energy storage system, the energy storage tank used to store liquid carbon dioxide is as follows: Figure 3 The diagram shows a vertical structure, including a tank 21 and a gas-liquid separation membrane 22. The gas-liquid separation membrane 22 divides the tank 21 into a liquid chamber 23 at the bottom and a gas chamber 24 at the top. The gas chamber 24 is connected to a second chamber 14 to balance the pressure in the tank 21. The liquid chamber 23 is connected to the second chamber 14 via a circulating pump and a heat exchanger. As an improvement, an insulation plate 25 is provided on the gas-liquid separation membrane 22. The insulation plate 25 adheres to the contact surface of the gas-liquid separation membrane 22 by its own weight. The insulation plate 25 is slidably connected to the tank 21. The insulation plate 25 is used to prevent heat exchange between the gaseous carbon dioxide in the gas chamber 24 and the liquid carbon dioxide in the liquid chamber 23, making the energy storage tank similar to the inclined temperature energy storage container 1. Under constant pressure conditions, heat exchange between media of different temperatures is minimized, maintaining a stable and reliable working state.

[0027] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A tilted-temperature energy storage container, comprising a container body, a diaphragm, and a heat insulation plate, wherein the diaphragm divides the container body into a first cavity and a second cavity, and one side of the heat insulation plate is attached to the outer surface of the diaphragm, characterized in that, The container body has a horizontal structure. A piston mechanism is provided in the first cavity of the container body. The piston mechanism includes a piston rod and a cylinder. The piston rod is rigidly connected to the other side of the heat insulation plate.

2. The inclined temperature energy storage container according to claim 1, characterized in that, The cylinder body has a nested structure. The outer cylinder body is fixedly connected to the container body, and the inner cylinder body is fitted inside the outer cylinder body and slides with the outer cylinder body. The piston slides and is limited in the inner cylinder body.

3. A sloped-temperature energy storage container according to claim 1 or 2, characterized in that, The first chamber is used to store air, and the second chamber is used to store carbon dioxide.

4. A sloped-temperature energy storage container according to claim 1 or 2, characterized in that, The diaphragm has a multi-layer composite structure, including a pressure-resistant layer in the middle and heat-insulating layers on both sides.

5. A compressed air energy storage system, characterized in that: The device includes the inclined temperature energy storage container as described in any one of claims 1-4, wherein the first cavity of the inclined temperature energy storage container is connected to the air compression energy storage subsystem and the air expansion energy release subsystem, and the second cavity of the inclined temperature energy storage container is connected to the energy storage tank of the carbon dioxide gas-liquid conversion subsystem.

6. A compressed air energy storage system according to claim 5, characterized in that, The energy storage tank includes a tank body, which is equipped with a gas-liquid isolation membrane and divided into a liquid chamber and a gas chamber. The gas chamber is connected to a second chamber, and the liquid chamber is connected to the second chamber through a circulating pump and a heat exchanger.

7. A compressed air energy storage system according to claim 6, characterized in that, An insulation plate is installed on the gas-liquid isolation membrane of the tank body, and the insulation plate is slidably connected to the tank body.

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