Compressed air energy storage power station salt cavern gas extraction dechlorination and dehumidification system

Abstract

This invention belongs to the field of energy storage technology and discloses a compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system. A cyclone separator is provided with an inlet and an outlet. The salt cavern gas storage tank is connected to the inlet, and the lower area of ​​the purifier is connected to the outlet. Ethylene glycol solution flows through the middle area inside the purifier. A coalescing filter element is installed in the upper area inside the purifier, circumferentially adhering to the inner wall of the purifier. An exhaust port connected to an expansion power generation system is opened at the top of the purifier. Compressed air from the salt cavern gas storage tank enters the cyclone separator through the inlet. The cyclone separator separates solid impurities from the compressed air. The compressed air then enters the purifier through the inlet. After preliminary purification by the first-stage cyclone separator, the compressed air enters the bubble cap section of the purifier. Residual chloride-containing droplets are first absorbed and captured by the ethylene glycol solution, and then coalesced and settled through the coalescing filter element, resulting in deep air purification and a significant reduction in chloride ion content.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to a compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system. Background Technology

[0002] Salt cavern underground gas storage is widely regarded as an ideal gas storage facility in CAES systems. The basic principle of salt cavern compressed air energy storage technology is to convert electrical energy into high-pressure air potential energy and store it in salt cavern underground gas storage during off-peak hours, and release compressed air during peak hours to drive generator sets to generate electricity, thereby achieving flexible adjustment and balance of grid load.

[0003] However, the interior of salt cavern underground gas storage facilities is a complex chemical environment characterized by high pressure, high humidity, and corrosive components such as chloride ions. Moisture in the salt cavern combines with chlorides to form chloride solutions, which exist as tiny free droplets in the compressed air. During the expansion power generation process, these chloride droplets in the compressed air can attack downstream heat exchanger pipes and expander blades, causing equipment corrosion and significantly shortening their service life. Therefore, it is necessary to remove chloride droplets from the compressed air. However, while current mechanical separation devices can remove some larger chloride droplets, their effectiveness in separating tiny droplets is limited, causing them to easily enter the subsequent power generation system with the airflow. Summary of the Invention

[0004] The purpose of this invention is to provide a compressed air energy storage power station salt cavern gas extraction dechlorination and dehumidification system, which can effectively remove chloride droplets from compressed air and reduce chloride ion concentration.

[0005] To achieve this objective, the present invention adopts the following technical solution: A compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system includes a cyclone separator and a purifier. The cyclone separator has an air inlet and an air outlet, and the salt cavern gas storage tank is connected to the air inlet. The cyclone separator is used to separate solid impurities in the compressed air. The lower region of the purifier is connected to the air outlet. An ethylene glycol solution flows through the middle region inside the purifier. The ethylene glycol solution is used to absorb large-diameter chloride droplets in the compressed air. A coalescing filter element is installed in the upper region inside the purifier. The coalescing filter element is circumferentially attached to the inner wall of the purifier. The coalescing filter element is used to separate and settle particulate chloride droplets in the compressed air. An exhaust port connected to an expansion power generation system is opened at the top of the purifier.

[0006] Preferably, the compressed air energy storage power station salt cavern gas extraction dechlorination and dehumidification system further includes a regenerator. The middle area of ​​the purifier has an inlet and an outlet spaced apart. The regenerator is located outside the purifier and is connected to the inlet and the outlet. The regenerator is configured to heat and regenerate the ethylene glycol solution.

[0007] Preferably, a dehydration component is provided in the middle area inside the purifier. The dehydration component includes a baffle, a riser pipe and a bubble cover. The baffle is circumferentially connected to the inner wall of the purifier. The bottom of the riser pipe is vertically inserted into the baffle and sealed with the baffle. The top of the riser pipe extends into the bubble cover. The liquid inlet is higher than the baffle, and the bottom of the liquid outlet is flush with the top of the riser pipe.

[0008] Preferably, the compressed air energy storage power station salt cavern gas extraction, dechlorination and dehumidification system further includes a rich solution storage tank and a lean solution storage tank. The lean solution storage tank is connected to the inlet, the outlet is connected to the rich solution storage tank, and the regenerator is located between the rich solution storage tank and the lean solution storage tank.

[0009] Preferably, the compressed air energy storage power station's salt cavern gas extraction, dechlorination, and dehumidification system further includes a rich solution booster pump and a lean solution booster pump. The rich solution booster pump is located between the rich solution storage tank and the regenerator and is used to pump the ethylene glycol solution into the regenerator. The lean solution booster pump is located between the lean solution storage tank and the inlet and is used to pump the ethylene glycol solution into the inlet.

[0010] Preferably, the bottom of the bubble is lower than the top of the riser pipe.

[0011] Preferably, the inlet and the outlet are flush.

[0012] Preferably, the regenerator is equipped with a heating wire inside; or, hot water circulates inside the regenerator.

[0013] Preferably, the lower region of the purifier has an air inlet that connects to the air outlet.

[0014] Preferably, a corrosion-resistant pipe is connected between the air outlet and the air inlet of the purifier.

[0015] The beneficial effects of this invention are: This invention provides a compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system, including a cyclone separator and a purifier. The cyclone separator has an inlet and an outlet, the salt cavern gas storage tank is connected to the inlet, the lower area of ​​the purifier is connected to the outlet, the middle area inside the purifier flows with an ethylene glycol solution, and the upper area inside the purifier is equipped with a coalescing filter element, which is circumferentially attached to the inner wall of the purifier. An exhaust port connected to an expansion power generation system is opened at the top of the purifier. Compressed air from the salt cavern gas storage tank enters the cyclone separator through the inlet. The cyclone separator separates solid impurities from the compressed air. Compressed air enters the purifier through the inlet and flows from bottom to top inside the purifier. After being separated by the first-stage cyclone separator, residual chloride-containing droplets are absorbed and captured by the ethylene glycol solution, and further coalesced and settled by the coalescing filter element. This effectively removes chloride droplets from the compressed air. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system provided in an embodiment of the present invention.

[0017] In the picture: 1. Cyclone separator; 11. Air inlet; 12. Air outlet; 2. Purifier; 21. Coalescing filter element; 22. Exhaust outlet; 23. Liquid inlet; 24. Liquid outlet; 25. Purifier air inlet; 26. Baffle; 27. Air riser pipe; 28. Bubble cap; 29. ​​Sewage outlet; 3. Regenerator; 4. Rich solution storage tank; 5. Lean solution storage tank; 6. Rich solution booster pump; 7. Lean solution booster pump. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0019] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" 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 or an electrical connection; 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. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0020] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0021] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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 present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0022] This embodiment provides a compressed air energy storage power station salt cavern gas extraction dechlorination and dehumidification system, which can effectively remove chloride droplets from compressed air.

[0023] Please see Figure 1 The compressed air energy storage power station salt cavern gas dechlorination and dehumidification system provided in this embodiment includes a cyclone separator 1 and a purifier 2. The cyclone separator 1 is used to separate solid impurities in compressed air, such as chloride crystals, and can also separate some free chloride droplets. The purifier 2 is used to further separate chloride droplets in compressed air.

[0024] Specifically, the cyclone separator 1 is provided with an air inlet 11, and the salt cavern gas storage tank is connected to the air inlet 11. Preferably, the compressed air in the salt cavern gas storage tank is first extracted through the injection and production tree, merged into the main pipeline, and then enters the cyclone separator 1 through the air inlet 11.

[0025] Cyclone separator 1 has a built-in high-efficiency cyclone separator. With the above settings, compressed air enters tangentially to generate a swirling flow. Relying on centrifugal force, it can efficiently separate and remove solid impurities ≥Φ10μm with a separation efficiency of not less than 99%. Under the action of centrifugal force, it can also separate some free chloride droplets in the compressed air.

[0026] Furthermore, the cyclone separator 1 is also provided with an air outlet 12, which is connected to the interior of the purifier 2. Compressed air with solid impurities removed enters the purifier 2, and the purifier 2 further separates the chloride droplets in the compressed air.

[0027] In this embodiment, an air inlet 25 is provided in the lower area of ​​the purifier 2. The air inlet 25 connects the interior of the purifier 2 with the air outlet 12 of the cyclone separator 1. Compressed air enters the purifier 2 through the air inlet 25.

[0028] Preferably, the air outlet 12 of the cyclone separator 1 and the air inlet 25 of the purifier 2 are connected by a corrosion-resistant pipe to avoid corrosion by chloride droplets in the compressed air.

[0029] Furthermore, an ethylene glycol solution flows through the middle area inside the purifier 2, and a coalescing filter element 21 is installed in the upper area inside the purifier 2. Compressed air enters the interior of the purifier 2 through the air inlet 25 and flows from bottom to top inside the purifier 2. The ethylene glycol solution captures the residual chloride-containing droplets after separation by the primary cyclone separator, and the coalescing filter element causes the droplets to coalesce and settle, thereby deeply removing chloride droplets from the compressed air and completing the purification.

[0030] Furthermore, an exhaust port 22 is opened on the top of the purifier 2. The exhaust port 22 is connected to the downstream expansion power generation system. The purified compressed air enters the expansion power generation system through the exhaust port 22 to generate electricity.

[0031] In this embodiment, an inlet 23 and an outlet 24 are spaced apart in the middle region of the purifier 2. The ethylene glycol solution enters the middle region of the purifier 2 through the inlet 23, absorbs and captures residual chloride droplets in the compressed air, and is discharged through the outlet 24. Preferably, the inlet 23 and the outlet 24 are flush.

[0032] It should be noted that ethylene glycol solutions with higher solute concentrations are ethylene glycol-lean solutions, which are highly hygroscopic, while ethylene glycol solutions with lower solute concentrations are ethylene glycol-rich solutions. The ethylene glycol-lean solution enters the central area of ​​the purifier 2 through inlet 23, where it absorbs large-diameter chloride droplets from the compressed air and transforms into an ethylene glycol-rich solution.

[0033] This embodiment also includes a dehydration component in the middle area inside the purifier 2 to achieve thorough washing of the compressed air and effectively remove chloride droplets from the compressed air.

[0034] For details, please continue reading Figure 1The dehydration assembly includes a baffle 26, a riser pipe 27, and a bubble cap 28. The baffle 26 is circumferentially connected to the inner wall of the purifier 2. The riser pipe 27 is vertically arranged, with its bottom inserted into the baffle 26, forming a sealed fit. The bubble cap 28 has a bottom-open structure, with its bottom lower than the top of the riser pipe 27. The top of the riser pipe 27 extends into the bottom opening of the bubble cap 28. Furthermore, an inlet 23 is provided above the baffle 26, and an outlet 24 is flush with the inlet 23. The bottom of the outlet 24 is flush with the top of the riser pipe 27.

[0035] With the above setup, the ethylene glycol lean solution enters the middle area inside the purifier 2 through the inlet 23. The ethylene glycol lean solution gathers above the baffle 26. Since the outlet 24 is flush with the inlet 23, the bottom of the bubble cap 28 is lower than the top of the riser pipe 27, and the highest liquid level of the ethylene glycol lean solution is higher than the bottom of the bubble cap 28 and flush with the top of the riser pipe 27, maintaining the formation of a liquid surface blockage of the ethylene glycol lean solution. The liquid surface blocks the annular gap formed by the riser pipe 27 and the bubble cap 28. The compressed air flowing from bottom to top inside the purifier 2 enters the space of the bubble cap 28 through the riser pipe 27 and passes through the liquid surface located in the annular gap in the form of bubbles and overflows, so that the compressed air and the ethylene glycol lean solution can fully contact each other, effectively removing residual chloride droplets in the compressed air. After absorbing the chloride droplets in the compressed air, it becomes an ethylene glycol rich solution, which can be discharged from the outlet 24.

[0036] Preferably, the baffle 26 and the air riser 27 are integrally formed.

[0037] For example, the bubble cap 28 is fixed to the inner wall of the purifier 2. In other feasible embodiments, the dehydration assembly includes at least two bubble caps 28 of the same height and corresponding air risers 27, each combination forming the same gap, through which compressed air flowing from bottom to top inside the purifier 2 passes in a bubbling manner through the liquid surface located in the gap, further absorbing and capturing residual chloride-containing droplets after passing through the primary cyclone separator.

[0038] The compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system provided in this embodiment also includes a regenerator 3 for heating and regenerating the ethylene glycol solution. Specifically, the regenerator 3 is located outside the purifier 2 and is connected to the inlet 23 and the outlet 24. It is used to heat the ethylene glycol-rich solution, evaporate the water therein, and increase the solute concentration to regenerate a lean ethylene glycol solution, thereby achieving continuous recycling of the ethylene glycol solution and significantly reducing operating costs and material consumption.

[0039] In some feasible embodiments, a heating wire is installed inside the regenerator 3, which generates heat when energized. In other feasible embodiments, hot water can also be introduced into the regenerator 3.

[0040] The compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system provided in this embodiment also includes a rich solution storage tank 4 and a lean solution storage tank 5. The lean solution storage tank 5 is connected to an inlet 23 for temporarily storing lean ethylene glycol solution, and an outlet 24 is connected to the rich solution storage tank 4 for temporarily storing rich ethylene glycol solution. A regenerator 3 is located between the rich solution storage tank 4 and the lean solution storage tank 5.

[0041] The compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system provided in this embodiment also includes a rich solution booster pump 6 and a lean solution booster pump 7. The rich solution booster pump 6 is located between the outlet of the rich solution storage tank 4 and the inlet of the regenerator 3, and is used to pump the temporarily stored ethylene glycol rich solution in the rich solution storage tank 4 into the regenerator 3 for regeneration. The lean solution booster pump 7 is located between the lean solution storage tank 5 and the inlet 23, and is used to pump the temporarily stored ethylene glycol lean solution in the lean solution storage tank 5 into the inlet 23 of the purifier 2.

[0042] Optionally, a drain outlet 29 can be opened at the bottom of the purifier 2, and a valve can be installed at the drain outlet 29. Opening the valve can periodically discharge the impurities accumulated at the bottom of the purifier 2.

[0043] It is understandable that the coalescing filter element 21 is a commonly used structure in the prior art, capable of capturing extremely fine droplets carried in the gas. Furthermore, the coalescing filter element 21 is circumferentially attached to the inner wall of the purifier 2. When compressed air passes through the coalescing filter element 21, the chloride droplets carried in it collide and coalesce on the fiber surface of the coalescing filter element 21, fusing into large-diameter chloride droplets. When the weight of the droplets exceeds the buoyancy of the gas and the drag force of the airflow, they automatically settle and fall back above the baffle 26 under the action of gravity. After this coalescing process, the clean compressed air passes through the coalescing filter element 21 from bottom to top, and the purified compressed air enters the expansion power generation system through the exhaust port 22 to complete the power generation.

[0044] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system, characterized in that, The system includes a cyclone separator (1) and a purifier (2). The cyclone separator (1) is provided with an air inlet (11) and an air outlet (12). A salt cavern gas storage tank is connected to the air inlet (11). The cyclone separator (1) is used to separate solid impurities in compressed air. The lower area of ​​the purifier (2) is connected to the air outlet (12). An ethylene glycol solution flows through the middle area inside the purifier (2). The ethylene glycol solution is used to absorb large-diameter chloride droplets in the compressed air. A coalescing filter element (21) is provided in the upper area inside the purifier (2). The coalescing filter element (21) is circumferentially attached to the inner wall of the purifier (2). The coalescing filter element (21) is used to separate and settle particulate chloride droplets in the compressed air. An exhaust port (22) connected to an expansion power generation system is opened at the top of the purifier (2).

2. The compressed air energy storage power station salt cavern gas extraction dechlorination and dehumidification system according to claim 1, the compressed air energy storage power station salt cavern gas extraction dechlorination and dehumidification system further includes a regenerator (3), the middle area of ​​the purifier (2) is provided with an inlet (23) and an outlet (24) at intervals, the regenerator (3) is disposed outside the purifier (2) and connects the inlet (23) and the outlet (24), the regenerator (3) is configured to heat and concentrate the ethylene glycol solution.

3. The compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system according to claim 2, characterized in that, A dehydration assembly is provided in the middle area inside the purifier (2). The dehydration assembly includes a baffle (26), a riser pipe (27), and a bubble cover (28). The baffle (26) is circumferentially connected to the inner wall of the purifier (2). The bottom of the riser pipe (27) is vertically inserted into the baffle (26) and sealed with the baffle (26). The top of the riser pipe (27) extends into the bubble cover (28). The liquid inlet (23) is higher than the baffle (26). The bottom of the liquid outlet (24) is flush with the top of the riser pipe (27).

4. The compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system according to claim 2, characterized in that, The compressed air energy storage power station salt cavern gas extraction dechlorination and dehumidification system also includes a rich solution storage tank (4) and a lean solution storage tank (5). The lean solution storage tank (5) is connected to the liquid inlet (23), and the liquid outlet (24) is connected to the rich solution storage tank (4). The regenerator (3) is located between the rich solution storage tank (4) and the lean solution storage tank (5).

5. The compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system according to claim 4, characterized in that, The compressed air energy storage power station salt cavern gas extraction dechlorination and dehumidification system also includes a rich solution booster pump (6) and a lean solution booster pump (7). The rich solution booster pump (6) is located between the rich solution storage tank (4) and the regenerator (3) and is used to pump ethylene glycol solution into the regenerator (3). The lean solution booster pump (7) is located between the lean solution storage tank (5) and the inlet (23) and is used to pump ethylene glycol solution into the inlet (23).

6. The compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system according to claim 3, characterized in that, The bottom of the blister (28) is lower than the top of the riser (27).

7. A compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system according to any one of claims 2-6, characterized in that, The inlet (23) is flush with the outlet (24).

8. A compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system according to any one of claims 2-6, characterized in that, The regenerator (3) is equipped with a heating wire inside; or, hot water circulates inside the regenerator (3).

9. A compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system according to any one of claims 1-6, characterized in that, An air inlet (25) is provided in the lower region of the purifier (2) to connect with the air outlet (12).

10. A compressed air energy storage power station salt cavern gas extraction, dechlorination, and dehumidification system according to claim 9, characterized in that, The air outlet (12) is connected to the air inlet (25) of the purifier by a corrosion-resistant pipe.

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