Compressed air energy storage system

Abstract

The invention discloses a compressed air energy storage system which comprises a compressor, a heat exchanger, an air storage mechanism and a turbine, and the compressor is used for absorbing air, compressing the air into high-pressure air and concentrating and heating moisture in the air; the heat exchanger comprises a shell, a gas flow channel and a water flow channel, the gas flow channel and the water flow channel are arranged in the shell in an isolated mode, a first gas inlet and a first gas outlet are formed in the two ends of the gas flow channel, and a first water inlet and a first water outlet are formed in the two ends of the water flow channel. The first water inlet is connected with the compressor, receives pressurized hot water and finally discharges the hot water through the first water outlet; the gas storage mechanism is connected with the first gas outlet and stores gas; in the energy release stage, the first gas inlet is disconnected with the compressor and connected to the turbine, the gas storage mechanism reversely releases gas, the heat exchanger releases heat energy and pressure potential energy stored in the energy storage stage to the gas, and the gas enters the turbine to expand and do work.

Description

Technical Field

[0001] This invention relates to the technical field of heat exchange energy storage, and more specifically to a compressed air energy storage system. Background Technology

[0002] Compressed air energy storage (CAES) uses compressed air as the energy storage medium and is a physical energy storage technology that uses mechanical equipment to store energy and transfer and utilize it across time and space. A CAES system mainly consists of two processes: energy storage and energy release. During energy storage, an electric motor drives a compressor to compress ambient air to a high-pressure state and store it in the storage device. Electrical energy is converted into the internal energy and pressure potential energy of the compressed air during this process. During energy release, the compressed air stored in the storage device enters an air turbine expander to expand and generate electricity. The internal energy and pressure potential energy contained in the compressed air are converted back into electrical energy during this process.

[0003] In related technologies, the shell-and-tube heat exchangers currently in use do not achieve ideal results in terms of size, cost, or heat exchange efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a compressed air energy storage system that, by using a heat exchanger with unequal flow channels, can achieve higher heat exchange efficiency while effectively reducing volume, saving on-site space, achieving lower costs, and improving the overall economic efficiency of the project.

[0005] Therefore, embodiments of the present invention propose a compressed air energy storage system.

[0006] A compressed air energy storage system according to an embodiment of the present invention includes: a compressor, a heat exchanger, a gas storage mechanism, and a turbine. The compressor is used to absorb air and compress it into high-pressure gas, and to concentrate and heat the moisture in the air. The heat exchanger includes a shell and a gas flow channel and a water flow channel disposed separately within the shell. The cross-sectional area of ​​the gas flow channel is larger than that of the water flow channel. A first air inlet and a first air outlet are provided at both ends of the gas flow channel, and a first water inlet and a first water outlet are provided at both ends of the water flow channel. During the energy storage stage, the first air inlet is connected to the compressor and receives high-pressure gas, and the first water inlet is connected to the compressor and receives pressurized hot water, which is finally discharged through the first water outlet. The gas storage mechanism is connected to the first air outlet and stores gas. During the energy release stage, the first air inlet is disconnected from the compressor and connected to the turbine. The gas storage mechanism releases gas in the reverse direction, and the heat exchanger releases the thermal energy and pressure potential energy stored during the energy storage stage to the gas. The heated gas enters the turbine and expands to do work.

[0007] In some embodiments, the compressed air energy storage system further includes a heat storage mechanism, which is connected to the heat exchanger and stores thermal energy.

[0008] In some embodiments, the heat exchanger further includes a corrugated plate with a continuous semi-annular cross-section, the gas flow channel being the inner side of the semi-annular shape and the water flow channel being the outer side of the semi-annular shape.

[0009] In some embodiments, the inner radius of the semi-circular ring is 5 mm, and the radius at the outer interface adjacent to the semi-circular ring is 0.5 mm.

[0010] In some embodiments, the thickness of the corrugated plate is 0.5 mm.

[0011] In some embodiments, the ratio of the length dimension to the width dimension of the corrugated plate is between 2:1 and 3:1.

[0012] In some embodiments, the compressed air energy storage system further includes: an intelligent control host computer, which can set a first state, wherein the first state is to release gas from the gas storage mechanism to the turbine; in the first state, the temperature monitoring probe of the intelligent control host computer monitors the temperature inside the heat exchanger and obtains temperature monitoring data; when the temperature monitoring data is lower than the temperature warning value of the heat exchanger, a first instruction is generated; based on the first instruction, the control valve of the gas storage mechanism increases the gas flow rate of the heat exchanger.

[0013] In some embodiments, there are multiple temperature monitoring probes, and when any one of the multiple temperature monitoring probes detects a temperature value lower than a temperature warning value, the first instruction is generated.

[0014] In some embodiments, the compressed air energy storage system further includes a heat dissipation mechanism, wherein the compressor is a multi-stage compression device, each stage of the compression device is connected by a pipe, the pipe passes through the heat dissipation mechanism, and the heat dissipation mechanism is a heat exchanger used to release excess heat.

[0015] In some embodiments, the compressed air energy storage system further includes a waste heat utilization mechanism, which includes a heat exchange component connected to the compressor and an external heating system.

[0016] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Other features and aspects of this disclosure will become clearer from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a compressed air energy storage system according to an embodiment of the present invention.

[0019] Figure 2 This is a perspective view of a heat exchanger according to an embodiment of the present invention.

[0020] Figure 3 This is a front view of a corrugated plate according to an embodiment of the present invention.

[0021] Figure label:

[0022] Compressed air energy storage system 100, compressor 10, heat exchanger 20, housing 21, first air inlet 211, first air outlet 212, first water inlet 213, first water outlet 214, corrugated plate 22, air storage mechanism 30, turbine 40. Detailed Implementation

[0023] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art should understand that the embodiments described below are only for illustrating the present invention and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] In the energy storage process of compressed air energy storage power stations, multi-stage compressors driven by off-peak electricity, wind, or solar power are typically used to compress ambient air to a high-pressure state. At this stage, a heat exchanger plays a crucial role, absorbing and storing the heat of compression. The cooled high-pressure air is then stored in a gas storage tank. During the energy release phase, the heat exchanger releases the heat stored during compression to the cooled compressed air. The heated air then enters a turbine, expands, and performs work, thereby driving a generator to produce electricity. The selection of the heat exchanger is critical to the system's efficiency, stability, and economy.

[0025] Currently used shell-and-tube heat exchangers fall short of ideal performance in terms of size, cost, and heat exchange efficiency. This welded, unequal flow channel plate heat exchanger design, with its large heat exchange area, achieves higher heat exchange efficiency compared to traditional shell-and-tube heat exchangers. It also effectively reduces equipment size, saves on-site space, lowers costs, and improves the overall project economy.

[0026] like Figures 1-3 As shown, the compressed air energy storage system 100 according to an embodiment of the present invention includes a compressor 10, a heat exchanger 20, an air storage mechanism 30, and a turbine 40.

[0027] The compressor 10 is used to absorb air, compress the air into high-pressure gas, and concentrate and heat the moisture in the air.

[0028] The heat exchanger 20 includes a shell 21 and a gas flow channel and a water flow channel arranged separately inside the shell 21. The cross-sectional area of ​​the gas flow channel is larger than that of the water flow channel. A first air inlet 211 and a first air outlet 212 are provided at both ends of the gas flow channel, and a first water inlet 213 and a first water outlet 214 are provided at both ends of the water flow channel.

[0029] During the energy storage phase, the first air inlet 211 is connected to the compressor 10 and receives high-pressure gas, the first water inlet 213 is connected to the compressor 10 and receives pressurized hot water, which is finally discharged through the first water outlet 214; the gas storage mechanism 30 is connected to the first air outlet 212 and stores gas.

[0030] During the energy release phase, the first air inlet 211 is disconnected from the compressor 10 and connected to the turbine 40. The gas storage mechanism 30 releases gas in the reverse direction. The heat exchanger 20 releases the thermal energy and pressure potential energy stored in the energy storage phase to the gas. The heated gas enters the turbine 40 to expand and do work.

[0031] In summary, the present invention aims to address the following issues: currently used shell-and-tube heat exchangers suffer from large footprint, low heat transfer efficiency, poor stability and economy, and cannot meet the requirements for high system efficiency.

[0032] In some embodiments, the compressed air energy storage system 100 further includes a heat storage mechanism, wherein the air storage mechanism 30 is connected to the heat exchanger 20 and stores thermal energy.

[0033] In some embodiments, the heat exchanger 20 further includes a corrugated plate 22, the cross-section of which is a continuous semi-annular shape, with the gas flow channel being the inner side of the semi-annular shape and the water flow channel being the outer side of the semi-annular shape.

[0034] Through the inventor's research, the heat exchanger 20 of the present invention has a double-sided unequal flow channel design realized by the corrugated plate 22 based on the unequal flow channels on the hot and cold sides. It can also realize the plate design of plate heat exchanger with high efficiency heat transfer under the condition that the physical properties of the medium (air / water) on both sides of the heat exchanger are very different in the absorption and heat release conditions.

[0035] In this invention, based on the different physical properties of the media (air / water) on both sides of the heat exchanger under the absorption and release conditions, the corrugated plate 22 is designed as a channel with unequal cross-sections on both sides. For the air side, it is designed with a large cross-section and high flow rate to reduce the pressure loss on the air side and improve the overall system efficiency. At the same time, the water side is designed with a small cross-section and low flow rate, which can improve the turbulence effect on the water side, enhance the heat transfer efficiency, and reduce the tendency of scaling on the water side.

[0036] Furthermore, in response to the large temperature difference in heat exchange during absorption and release processes, hairpin or multi-pass structures were previously required to increase the heat transfer length. Now, by increasing the aspect ratio of the plate heat exchanger plates, the heat transfer length can be increased, and a single-pass structure can meet the requirements of large temperature difference heat exchange processes. A fully welded design is adopted to increase the overall pressure resistance of the equipment.

[0037] In some embodiments, the inner radius of the semi-circle is 5 mm, and the radius at the outer interface of the adjacent semi-circle is 0.5 mm.

[0038] In some embodiments, the thickness of the corrugated plate 22 is 0.5 mm.

[0039] In some embodiments, the ratio of the length dimension to the width dimension of the corrugated plate 22 is between 2:1 and 3:1.

[0040] Preferably, based on software calculations and fluid dynamics analysis, the heat exchanger plate texture and various dimensions, including groove depth, corrugation type, intercept, and channel size, are designed. After thermal calculations and fluid dynamics analysis, the plate shape is finalized, molds are designed, and cold-pressing tests are conducted. Following the pressure test, assembly and welding are performed to confirm the structural pressure-bearing reliability. Thermal tests are conducted on a test platform to ensure that the thermal test results are consistent with the software simulation results, allowing the equipment to be applied to relevant applications.

[0041] In some embodiments, the compressed air energy storage system 100 further includes: an intelligent control host computer, which can set a first state, wherein the first state is to release gas from the gas storage mechanism 30 to the turbine 40; in the first state, the temperature monitoring probe of the intelligent control host computer monitors the temperature inside the heat exchanger 20 and obtains temperature monitoring data; when the temperature monitoring data is lower than the temperature warning value of the heat exchanger 20, a first instruction is generated; based on the first instruction, the control valve of the gas storage mechanism 30 increases the gas flow rate of the heat exchanger.

[0042] In some embodiments, there are multiple temperature monitoring probes. When any one of the multiple temperature monitoring probes detects a temperature value lower than the temperature warning value, a first instruction is generated.

[0043] Understandably, the intelligent control host computer is the control center for controlling and managing the entire compressed air energy storage system 100. The intelligent control host computer regulates the energy storage and power generation processes through software algorithms or hardware control.

[0044] The intelligent control host computer sets the compressed air energy storage system 100 to a first state, which is to release gas from the gas storage mechanism 30 to the turbine 40. In short, this means that the intelligent control host computer, through corresponding operations, causes the gas storage mechanism 30 to start releasing compressed air and guides this compressed air to the turbine 40 so as to use this air to generate electricity.

[0045] In the first state, the temperature inside the heat exchanger 20 is monitored by a temperature monitoring probe to obtain temperature monitoring data, which includes multiple temperature values ​​from multiple temperature monitoring points. In the first state, when any of the multiple temperature values ​​falls below a temperature warning value, a first control command is generated.

[0046] Understandably, a temperature warning value is established to indicate the safe temperature range. This warning value can be determined based on factors such as design requirements, equipment specifications, or operating experience. When any of the monitored temperature values ​​falls below the set intra-pipe temperature warning value, it indicates a possible temperature anomaly or excessively low temperature. In this case, a first instruction is generated to adjust the operation of the heat exchanger to ensure the temperature is maintained within the safe range.

[0047] In some embodiments, the compressed air energy storage system 100 further includes a heat dissipation mechanism, wherein the compressor 10 is a multi-stage compression device, each stage of the compression device is connected by a pipe, the pipe is installed in the heat dissipation mechanism, and the heat dissipation mechanism is a heat exchanger used to release excess heat.

[0048] In some embodiments, the compressed air energy storage system 100 further includes a waste heat utilization mechanism, which includes a heat exchange component connected to the compressor 10 and the external heating system respectively.

[0049] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to 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 this invention.

[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0051] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0052] In this 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," "over," and "on top" of 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.

[0053] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the 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.

[0054] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A compressed air energy storage system, characterized in that, include: A compressor for absorbing air, compressing the air into a high-pressure gas, and concentrating and heating the moisture in the air; A heat exchanger includes a shell and a gas flow channel and a water flow channel arranged separately within the shell. The cross-sectional area of ​​the gas flow channel is larger than that of the water flow channel. A first air inlet and a first air outlet are provided at both ends of the gas flow channel, and a first water inlet and a first water outlet are provided at both ends of the water flow channel. During the energy storage stage, the first air inlet is connected to the compressor and receives high-pressure gas, and the first water inlet is connected to the compressor and receives pressurized hot water, which is finally discharged through the first water outlet. A gas storage mechanism is connected to the first gas outlet and stores gas. In the energy release phase, the first air inlet is disconnected from the compressor and connected to the turbine. The gas storage mechanism releases gas in the reverse direction. The heat exchanger releases the thermal energy and pressure potential energy stored in the energy storage phase to the gas. The heated gas enters the turbine and expands to do work.

2. The compressed air energy storage system according to claim 1, characterized in that, Also includes: A heat storage mechanism, wherein the gas storage mechanism is connected to the heat exchanger and stores thermal energy.

3. The compressed air energy storage system according to claim 1, characterized in that, The heat exchanger also includes a corrugated plate with a continuous semi-annular cross-section. The gas flow channel is the inner side of the semi-annular shape, and the water flow channel is the outer side of the semi-annular shape.

4. The compressed air energy storage system according to claim 3, characterized in that, The inner radius of the semi-circular ring is 5 mm, and the radius at the outer interface of the adjacent semi-circular ring is 0.5 mm.

5. The compressed air energy storage system according to claim 3, characterized in that, The thickness of the corrugated plate is 0.5 mm.

6. The compressed air energy storage system according to claim 3, characterized in that, The ratio of the length to the width of the corrugated plate is between 2:1 and 3:

1.

7. The compressed air energy storage system according to claim 1, characterized in that, Also includes: The intelligent control host computer can set a first state, which is to release gas from the gas storage mechanism to the turbine. In the first state, the temperature monitoring probe of the intelligent control host computer monitors the temperature inside the heat exchanger and obtains temperature monitoring data. When the temperature monitoring data is lower than the temperature warning value of the heat exchanger, a first instruction is generated. Based on the first instruction, the control valve of the gas storage mechanism increases the gas flow rate of the heat exchanger.

8. The compressed air energy storage system according to claim 7, characterized in that, The temperature monitoring probes are multiple, and when any one of the multiple temperature monitoring probes detects a temperature value lower than the temperature warning value, the first instruction is generated.

9. The compressed air energy storage system according to claim 1, characterized in that, Also includes: The heat dissipation mechanism is a multi-stage compression device, with each stage connected by pipes. The pipes pass through the heat dissipation mechanism, which is a heat exchanger used to release excess heat.

10. The compressed air energy storage system according to claim 1, characterized in that, Also includes: The waste heat utilization mechanism includes a heat exchange component, which is connected to the compressor and the external heating system respectively.

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