An electrochemical carbon capture desorption system and method based on periodic ultrasonic intensification
By using a periodically ultrasound-enhanced electrochemical carbon capture and desorption system, combined with ultrasound and potential/pH adjustment, the problems of low desorption rate and high energy consumption in traditional electrochemical desorption processes have been solved, achieving efficient carbon dioxide desorption and extended electrode life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUANENG CLEAN ENERGY RES INST
- Filing Date
- 2026-03-27
- Publication Date
- 2026-06-26
AI Technical Summary
Traditional electrochemical desorption processes suffer from problems such as low desorption rate, high energy consumption, electrode passivation and damage, and are limited by mass transfer and reaction rate.
An electrochemical carbon capture and desorption system enhanced by periodic ultrasound is used to achieve efficient carbon dioxide desorption by applying periodic pulsed ultrasound during the desorption stage, combined with the adjustment of potential and pH.
It improves carbon dioxide desorption efficiency, reduces system energy consumption, extends electrode life, and avoids fatigue damage to electrode materials.
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Figure CN122273273A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of carbon capture technology. Specifically, this invention relates to an electrochemical carbon capture and desorption system and method based on periodic ultrasonic enhancement. Background Technology
[0002] With the increasing severity of global climate change, carbon capture, utilization and storage (CCUS) has become an important means of mitigating greenhouse gas emissions. Among them, electrochemical carbon capture technology has attracted widespread attention due to its advantages such as high efficiency, low energy consumption and mild conditions.
[0003] Traditional electrochemical desorption processes mainly rely on adjusting electrode potential or controlling solution pH to release carbon dioxide. However, due to limitations in mass transfer and reaction rate, continuous adjustment of potential or pH requires a large amount of energy, and prolonged high-intensity operation can cause electrode material fatigue, reduce system stability, and result in problems such as low desorption rate, high energy consumption, electrode passivation, and damage.
[0004] In view of this, the present invention is hereby proposed. Summary of the Invention
[0005] This invention aims to at least partially address one of the technical problems in related technologies. To this end, embodiments of this invention propose an electrochemical carbon capture and desorption system and method based on periodic ultrasonic enhancement.
[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:
[0007] In a first aspect, embodiments of the present invention propose an electrochemical carbon capture and desorption system based on periodic ultrasonic enhancement, the system comprising an electrochemical reaction unit, an ultrasonic unit, a control unit, and a separation and purification unit; The electrochemical reaction unit includes an electrochemical cell, which includes an adsorption electrode, a counter electrode, and an electrolyte. The ultrasonic unit includes an ultrasonic generator and a piezoelectric transducer. The ultrasonic generator is electrically connected to the piezoelectric transducer. The piezoelectric transducer is located at the bottom of the electrochemical cell and is in close contact with the bottom outer wall of the electrochemical cell to ensure that the ultrasonic mechanical waves can efficiently penetrate the bottom outer wall of the electrochemical cell and act on the internal electrolyte. The control unit includes an integrated timing controller, an electrochemical workstation, and an ultrasonic drive component, used to monitor the adsorption and desorption state of carbon dioxide in the electrochemical cell, so as to synchronously trigger the ultrasonic unit to apply ultrasonic waves in a periodic pulse mode when the electrochemical cell is performing desorption operation, thereby realizing intelligent synchronization between periodic ultrasonic enhancement and the electrochemical desorption process. The separation and purification unit includes a flash tank and a compressor. The inlet of the flash tank is connected to the outlet of the electrochemical cell, and the outlet of the flash tank is connected to the inlet of the compressor.
[0008] This invention employs periodic pulsed ultrasound enhancement technology during the desorption stage of electrochemical carbon capture to dynamically enhance the carbon dioxide desorption efficiency, reduce overall system energy consumption, and improve electrode lifespan.
[0009] In some embodiments, the adsorption electrode is a porous carbon-based adsorption electrode; And / or, the counter electrode is any one of a platinum electrode, a graphite electrode, a nickel foam electrode, a stainless steel electrode, or an iridium-tantalum coated electrode.
[0010] In some embodiments, when the electrochemical cell performs carbon dioxide adsorption, the electrolyte is an alkaline electrolyte, including any one of potassium hydroxide solution, potassium carbonate solution, and potassium bicarbonate solution; And / or, when the electrochemical cell performs carbon dioxide desorption operation, the electrolyte is an acidic electrolyte, including any one of sulfuric acid solution and hydrochloric acid solution.
[0011] In some embodiments, the rated power of the ultrasonic generator is 100-500W.
[0012] In some embodiments, when ultrasound is applied in a periodic pulse pattern, the duty cycle of the ultrasound is 50%.
[0013] Secondly, embodiments of the present invention also propose an electrochemical carbon capture and desorption method based on periodic ultrasonic enhancement, implemented using the system described in the first aspect, the method comprising the following steps: (1) Passing the flue gas containing carbon dioxide into the electrochemical cell, and applying a negative potential to the adsorption electrode under alkaline electrolyte conditions, so that the carbon dioxide in the flue gas is captured and converted into carbonate or bicarbonate and stored on the surface of the adsorption electrode. (2) Stop supplying flue gas and apply a positive potential to the adsorption electrode under acidic electrolyte conditions; at the same time, trigger the ultrasonic unit through the control unit to apply ultrasonic waves to the electrochemical cell in a periodic pulse mode to desorb carbon dioxide. (3) The gas-rich electrolyte obtained after desorption in step (2) is subjected to vacuum flash evaporation so that the carbon dioxide dissolved in the liquid can be rapidly released from the liquid phase to achieve gas-liquid separation. (4) The gaseous carbon dioxide separated in step (3) is compressed to obtain high-pressure carbon dioxide gas or liquid carbon dioxide.
[0014] In some embodiments, in step (1), the pH value of the alkaline electrolyte is 10-14.
[0015] In some embodiments, in step (2), the pH value of the acidic electrolyte is 1-4; And / or, the ultrasonic waves are applied in the following manner: 2 minutes of ultrasonic waves + 2 minutes of no ultrasonic waves, alternating in a cycle.
[0016] In some embodiments, in step (3), the pressure during the reduced pressure flash evaporation is 0.01-0.08 MPa and the temperature is 40-80℃.
[0017] In some embodiments, in step (4), the outlet pressure during the compression process is 5-15 MPa and the temperature is 35-50°C.
[0018] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the structure of the electrochemical carbon capture and desorption system based on periodic ultrasound enhancement according to an embodiment of the present invention.
[0020] Figure labels: 1-Ultrasonic generator, 2-Piezoelectric transducer, 3-Electrochemical cell, 301-Adsorption electrode, 302-Counter electrode, 303-Electrolyte, 4-Flash tank, 5-Compressor. Detailed Implementation
[0021] The embodiments of the present invention are described in detail below. These embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.
[0022] In this invention, when a value is described as a range, it should be understood that such disclosure includes disclosure of all possible subranges within that range, as well as specific numerical values falling within that range, regardless of whether specific numerical values or specific subranges are explicitly specified.
[0023] In this invention, the terms “comprising” and “including” and their various variations mean that other elements or wholes may be included but are not specifically described.
[0024] In this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.
[0025] This invention is based on the inventor's discoveries and understanding of the following facts and problems: In electrochemical carbon capture systems, the reaction does not occur randomly in the air or deep within the liquid, but rather at a highly precise "interface": a gas-liquid-solid three-phase interface reaction. The solid phase is the electrode, the site of electron donation; the liquid is the electrolyte, carrying dissolved carbon dioxide (or carbonates or bicarbonates) across the electrode; and the gas phase is formed when desorption begins with the application of current, as carbon dioxide escapes from the liquid, forming bubbles. These carbon dioxide bubbles are generated at the interface between the electrode (solid) and the electrolyte (liquid), thus creating the gas-liquid-solid three-phase interface. At this point, the bubbles adhere to the electrode surface, obscuring it and thus limiting the desorption efficiency. Based on this, this invention uses time-series control to precisely trigger ultrasound only during the desorption phase. The cavitation effect of the ultrasound instantly breaks down the mass transfer resistance at the three-phase interface, detaching the tiny carbon dioxide bubbles from the electrode, keeping the electrode surface clean and maintaining the high-speed, continuous desorption reaction. This on-demand reinforcement logic of the invention solves the bubble shielding problem and avoids damage to the electrode material from continuous ultrasound.
[0026] The basic principles and beneficial effects of this invention are as follows: 1) Cavitation effect: When ultrasound propagates in a liquid, it generates periodic pressure changes, triggering the formation, expansion, and violent collapse of tiny bubbles (cavitation effect). This process can lead to: Local high temperature and high pressure: The high temperature (thousands of K) and high pressure (hundreds of atmospheres) generated at the moment of bubble collapse may destroy the binding of carbon dioxide on the surface of the adsorption electrode and promote desorption.
[0027] Microjets and shear force: The microjets generated when bubbles collapse can wash over the surface of the adsorption electrode, accelerating the removal of carbon dioxide from the active sites.
[0028] 2) Enhanced mass transfer: Turbulence and vibration caused by ultrasound can significantly improve the mass transfer rate in solution and reduce the diffusion resistance of carbon dioxide on the adsorption electrode surface or in the solution during desorption.
[0029] 3) Electrode surface activation: Ultrasound may clean the electrode surface, remove the passivation layer or by-products, maintain the activity of electrochemical reaction, and indirectly promote desorption efficiency.
[0030] 4) Ultrasonic-assisted electrochemical desorption: When a reverse potential or pH switching is applied, ultrasound can accelerate the interfacial reaction kinetics and shorten the desorption time; at the same time, it may also reduce the potential or acid / base consumption required for desorption, thereby reducing the overall energy consumption.
[0031] Firstly, such as Figure 1 As shown, this embodiment of the invention proposes an electrochemical carbon capture and desorption system based on periodic ultrasound enhancement. The system includes an electrochemical reaction unit, an ultrasound unit, a control unit, and a separation and purification unit. The electrochemical reaction unit includes an electrochemical cell 3, which is one of the core devices of the system. It includes an adsorption electrode 301, a counter electrode 302, and an electrolyte 303. Carbon dioxide adsorption and desorption occur in the electrochemical cell 3. The ultrasonic unit includes an ultrasonic generator 1 and a piezoelectric transducer 2. The ultrasonic generator 1 is electrically connected to the piezoelectric transducer 2. The piezoelectric transducer 2 is located at the bottom of the electrochemical cell 3 and is tightly fitted to the bottom outer wall of the electrochemical cell 3 to ensure that the ultrasonic mechanical waves can efficiently penetrate the bottom outer wall of the electrochemical cell 3 and act on the internal electrolyte 303. That is, it can be understood that the ultrasonic generator 1 is equivalent to an independent control box, while the piezoelectric transducer 2 is the core vibration source, and the bottom of the electrochemical cell 3 is the energy receiver to receive the ultrasonic waves transmitted by the piezoelectric transducer 2.
[0032] The control unit includes an integrated timing controller, an electrochemical workstation, and an ultrasonic drive component (not shown in the figure), used to monitor the adsorption and desorption states of carbon dioxide in the electrochemical cell 3. When the electrochemical cell 3 is undergoing desorption, the control unit synchronously triggers the ultrasonic unit to apply ultrasonic waves in a periodic pulse mode, achieving intelligent synchronization between periodic ultrasonic enhancement and the electrochemical desorption process. This control unit can record changes in electrode potential over time or with current, thereby monitoring whether the electrochemical cell 3 is in a carbon dioxide adsorption or desorption state, facilitating control of the ultrasonic wave application method and timing. The separation and purification unit is used to separate and compress the desorbed carbon dioxide. The unit includes a flash tank 4 and a compressor 5. The inlet of the flash tank 4 is connected to the outlet of the electrochemical cell 3, and the outlet of the flash tank 4 is connected to the inlet of the compressor 5. The desorbed carbon dioxide is compressed in multiple stages by the compressor 5 to convert it into a high-pressure gaseous or liquid state, which is convenient for subsequent storage or industrial use.
[0033] In some embodiments, the adsorption electrode is a porous carbon-based adsorption electrode; And / or, the counter electrode is any one of a platinum electrode, a graphite electrode, a nickel foam electrode, a stainless steel electrode, or an iridium-tantalum coated electrode, wherein the platinum electrode has extremely high catalytic activity and stability; while the graphite electrode and the nickel foam electrode have high cost performance and large specific surface area, making them suitable for industrial-grade application.
[0034] In some embodiments, when the electrochemical cell 3 performs carbon dioxide adsorption, the electrolyte is an alkaline electrolyte, including any one of potassium hydroxide solution, potassium carbonate solution, and potassium bicarbonate solution; And / or, when the electrochemical cell 3 performs carbon dioxide desorption, the electrolyte is an acidic electrolyte, including any one of sulfuric acid solution and hydrochloric acid solution; in addition, the enriched bicarbonate solution generated after carbon dioxide adsorption can also be used as an acidic electrolyte after anodic acidification.
[0035] In some embodiments, the rated power of the ultrasonic generator 1 is 100-500W, and its power output can be flexibly adjusted by a timing controller to match the desorption requirements under different concentrations of electrolyte.
[0036] In some embodiments, when ultrasound is applied in a periodic pulse mode, the duty cycle of the ultrasound is 50%. By applying ultrasound in a periodic pulse mode, fatigue damage to the electrode material and overheating of the electrolyte (energy waste) caused by continuous ultrasound can be effectively avoided. While maintaining a high desorption rate, the service life of expensive porous electrodes is significantly extended, resulting in significant economic benefits.
[0037] Secondly, embodiments of the present invention also propose an electrochemical carbon capture and desorption method based on periodic ultrasonic enhancement, implemented using the system described in the first aspect, the method comprising the following steps: (1) Passing the flue gas containing carbon dioxide into the electrochemical cell, and applying a negative potential to the adsorption electrode under alkaline electrolyte conditions, so that the carbon dioxide in the flue gas is captured and converted into carbonate or bicarbonate and stored on the surface of the adsorption electrode. (2) Stop supplying flue gas and apply a positive potential to the adsorption electrode under acidic electrolyte conditions; at the same time, trigger the ultrasonic unit through the control unit to apply ultrasonic waves to the electrochemical cell in a periodic pulse mode to desorb carbon dioxide. (3) The gas-rich electrolyte obtained after desorption in step (2) is subjected to vacuum flash evaporation so that the carbon dioxide dissolved in the liquid can be rapidly released from the liquid phase to achieve gas-liquid separation. (4) The gaseous carbon dioxide separated in step (3) is compressed to obtain high-pressure carbon dioxide gas or liquid carbon dioxide.
[0038] In some embodiments, in step (1), the pH value of the alkaline electrolyte is 10-14. In a strongly alkaline environment, it is more conducive to converting carbon dioxide in flue gas into carbonate or bicarbonate ions.
[0039] In some embodiments, in step (2), the pH value of the acidic electrolyte is 1-4. In an acidic environment, it is more conducive to the decomposition of carbonates or bicarbonates to release pure carbon dioxide bubbles. And / or, the ultrasonic waves are applied in the following manner: 2 minutes of ultrasonic waves + 2 minutes of no ultrasonic waves, alternating in a cycle.
[0040] In some embodiments, in step (3), the pressure during the reduced pressure flash evaporation is 0.01-0.08 MPa (absolute pressure) and the temperature is 40-80°C. By maintaining a vacuum (negative pressure) and supplementing it with gentle heating in the flash evaporator, the solubility of carbon dioxide in the liquid phase can be significantly reduced, thereby accelerating gas-liquid separation.
[0041] In some embodiments, during step (4), the outlet pressure of the compression process is 5-15 MPa and the temperature is 35-50°C, which can improve the compression efficiency while preventing damage to the equipment due to overheating. After compression, it is more convenient to store or transport carbon dioxide.
[0042] As a specific exemplary embodiment, this embodiment provides an electrochemical carbon capture and desorption method based on periodic ultrasound enhancement, which is implemented using the aforementioned electrochemical carbon capture and desorption system based on periodic ultrasound enhancement, and includes the following steps: (1) Adsorption stage: Flue gas containing carbon dioxide is introduced into an electrochemical cell (where the counter electrode is a graphite electrode), and under alkaline electrolyte (1M potassium hydroxide solution, pH value 12.5), a negative potential is applied to the adsorption electrode (porous carbon-based adsorption electrode) so that the carbon dioxide in the flue gas is captured and converted into carbonate or bicarbonate and stored on the surface of the adsorption electrode. (2) Desorption stage: Stop the delivery of flue gas and apply a positive potential to the adsorption electrode under acidic electrolyte (0.5M sulfuric acid, pH value 2.0); at the same time, start periodic pulse ultrasound synchronously so that the ultrasound runs at a duty cycle of 50% (working for 2 minutes and resting for 2 minutes) to stably desorb carbon dioxide. (3) Separation and storage: The rich electrolyte obtained after desorption in step (2) is transported to the flash tank and subjected to reduced pressure flash evaporation at 0.05 MPa (absolute pressure) and a working temperature of 60°C, so that the carbon dioxide dissolved in the liquid can be rapidly released from the liquid phase to achieve gas-liquid separation. The lean liquid obtained after separation is returned to the electrochemical cell for the next cycle. (4) Post-processing: The gaseous carbon dioxide separated in step (3) is transported to the compressor and compressed at 10 MPa and 40°C to obtain 10 MPa high-pressure carbon dioxide gas.
[0043] 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.
[0044] 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.
[0045] 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.
[0046] 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.
[0047] 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.
[0048] 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. An electrochemical carbon capture and desorption system based on periodic ultrasonic enhancement, characterized in that, The system includes an electrochemical reaction unit, an ultrasonic unit, a control unit, and a separation and purification unit; The electrochemical reaction unit includes an electrochemical cell, which includes an adsorption electrode, a counter electrode, and an electrolyte. The ultrasonic unit includes an ultrasonic generator and a piezoelectric transducer. The ultrasonic generator is electrically connected to the piezoelectric transducer. The piezoelectric transducer is located at the bottom of the electrochemical cell and is in close contact with the bottom outer wall of the electrochemical cell to ensure that the ultrasonic mechanical waves can efficiently penetrate the bottom outer wall of the electrochemical cell and act on the internal electrolyte. The control unit includes an integrated timing controller, an electrochemical workstation, and an ultrasonic drive component, used to monitor the adsorption and desorption state of carbon dioxide in the electrochemical cell, so as to synchronously trigger the ultrasonic unit to apply ultrasonic waves in a periodic pulse mode when the electrochemical cell is performing desorption operation, thereby realizing intelligent synchronization between periodic ultrasonic enhancement and the electrochemical desorption process. The separation and purification unit includes a flash tank and a compressor. The inlet of the flash tank is connected to the outlet of the electrochemical cell, and the outlet of the flash tank is connected to the inlet of the compressor.
2. The electrochemical carbon capture and desorption system based on periodic ultrasonic enhancement according to claim 1, characterized in that, The adsorption electrode is a porous carbon-based adsorption electrode; And / or, the counter electrode is any one of a platinum electrode, a graphite electrode, a nickel foam electrode, a stainless steel electrode, or an iridium-tantalum coated electrode.
3. The electrochemical carbon capture and desorption system based on periodic ultrasonic enhancement according to claim 1, characterized in that, When the electrochemical cell performs carbon dioxide adsorption, the electrolyte is an alkaline electrolyte, including any one of potassium hydroxide solution, potassium carbonate solution, and potassium bicarbonate solution; And / or, when the electrochemical cell performs carbon dioxide desorption operation, the electrolyte is an acidic electrolyte, including any one of sulfuric acid solution and hydrochloric acid solution.
4. The electrochemical carbon capture and desorption system based on periodic ultrasonic enhancement according to claim 1, characterized in that, The rated power of the ultrasonic generator is 100-500W.
5. The electrochemical carbon capture and desorption system based on periodic ultrasonic enhancement according to claim 1, characterized in that, When applying ultrasound in a periodic pulse mode, the duty cycle of the ultrasound is 50%.
6. A method for electrochemical carbon capture and desorption based on periodic ultrasonic enhancement, implemented using the system described in any one of claims 1-5, characterized in that, The method includes the following steps: (1) Passing the flue gas containing carbon dioxide into the electrochemical cell, and applying a negative potential to the adsorption electrode under alkaline electrolyte conditions, so that the carbon dioxide in the flue gas is captured and converted into carbonate or bicarbonate and stored on the surface of the adsorption electrode. (2) Stop supplying flue gas and apply a positive potential to the adsorption electrode under acidic electrolyte conditions; at the same time, trigger the ultrasonic unit through the control unit to apply ultrasonic waves to the electrochemical cell in a periodic pulse mode to desorb carbon dioxide. (3) The gas-rich electrolyte obtained after desorption in step (2) is subjected to vacuum flash evaporation so that the carbon dioxide dissolved in the liquid can be rapidly released from the liquid phase to achieve gas-liquid separation. (4) The gaseous carbon dioxide separated in step (3) is compressed to obtain high-pressure carbon dioxide gas or liquid carbon dioxide.
7. The electrochemical carbon capture and desorption method based on periodic ultrasonic enhancement according to claim 6, characterized in that, In step (1), the pH value of the alkaline electrolyte is 10-14.
8. The electrochemical carbon capture and desorption method based on periodic ultrasonic enhancement according to claim 6, characterized in that, In step (2), the pH value of the acidic electrolyte is 1-4; And / or, the ultrasonic waves are applied in the following manner: 2 minutes of ultrasonic waves + 2 minutes of no ultrasonic waves, alternating in a cycle.
9. The electrochemical carbon capture and desorption method based on periodic ultrasonic enhancement according to claim 6, characterized in that, In step (3), the pressure during the reduced pressure flash evaporation is 0.01-0.08 MPa and the temperature is 40-80℃.
10. The electrochemical carbon capture and desorption method based on periodic ultrasonic enhancement according to claim 6, characterized in that, In step (4), the outlet pressure during the compression process is 5-15 MPa and the temperature is 35-50℃.