Electrochemical carbon capture flue gas purification method and system

Abstract

The invention discloses an electrochemical carbon capture flue gas purification method and system, and relates to the technical field of carbon capture and utilization. The electrochemical carbon capture flue gas purification method comprises the following steps: S1, introducing flue gas to be treated into a washing tower, and absorbing metal ions in the flue gas by a washing liquid; s2, the washing liquid is introduced into an electrolytic bath, metal ions in the washing liquid are precipitated and attached to a cathode of the electrolytic bath through electro-deposition, and the washing liquid in the electrolytic bath is introduced into a washing tower; s3, the absorbent in the absorption tower reacts with the intermediate flue gas to generate a pregnant solution, the pregnant solution is introduced into the electrolytic bath, and the electrode attached with the metal ion precipitate serves as an anode to conduct an electrochemical mediation amine regeneration reaction on the pregnant solution; and S4, collecting carbon dioxide generated in the electrolytic bath, and conveying barren liquor generated by desorption of the rich liquor to an absorption tower. According to the electrochemical carbon capture flue gas purification method, metal ions in the flue gas can be collected so as to reduce electrode consumption in the electrochemical mediation amine regeneration carbon dioxide capture process, and the production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon capture and utilization, and in particular to an electrochemical carbon capture flue gas purification method and a system thereof. Background Art

[0002] Electrochemically mediated amine regeneration (EMAR) carbon dioxide capture technology is a new type of carbon dioxide capture technology that combines the high removal rate of organic amine absorption method and the high efficiency of electrochemical system, which can improve the collection efficiency in the carbon dioxide capture process.

[0003] The working principle of EMAR technology is as follows: under normal pressure, flue gas and absorbent are in countercurrent contact in the absorption tower. After absorbing carbon dioxide, the absorbent becomes a carbon dioxide-rich liquid and enters the desorption process. In the desorption process, the electrochemically mediated amine regeneration method is used. Under a certain voltage, the anode copper dissolves into the solution to replace carbon dioxide and coordinate with monoethanolamine (MEA) to desorb carbon dioxide. The Cu(II)-MEA complex solution enters the cathode tank to precipitate copper and realize solvent regeneration. The regenerated MEA solution can flow back into the absorption tower to participate in carbon dioxide absorption again, thereby realizing the absorption-desorption cycle.

[0004] However, during the use of EMAR technology, there are problems such as high electrode consumption rate, high consumption, and the need to regularly replace electrodes or the entire electrolyzer, which increases the overall cost of electrochemically mediated amine regeneration carbon dioxide capture technology. Summary of the invention

[0005] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0006] To this end, an embodiment of the present invention proposes an electrochemical carbon capture flue gas purification method, which can collect metal ions in the flue gas and use them in the desorption process of carbon dioxide, reduce the consumption of electrodes in the electrochemical mediated amine regeneration carbon dioxide capture process, and thus reduce the production cost of electrochemical mediated amine regeneration carbon dioxide capture.

[0007] The embodiment of the present invention also provides an electrochemical carbon capture flue gas purification system.

[0008] The electrochemical carbon capture flue gas purification method of the embodiment of the present invention comprises the following steps: S1: The flue gas to be treated is passed into a scrubbing tower, the metal ions in the flue gas are absorbed by the scrubbing liquid, and the intermediate flue gas generated after being scrubbed by the scrubbing tower is passed into an absorption tower; S2: passing the washing liquid that absorbs metal ions into the electrolytic cell, precipitating the metal ions in the washing liquid onto the cathode of the electrolytic cell through electrodeposition, and passing the washing liquid in the electrolytic cell into the washing tower after the metal ions are completely precipitated; S3: The absorbent in the absorption tower reacts with the intermediate flue gas to absorb carbon dioxide to generate a rich liquid, which is passed into the electrolytic cell, and an electrode with metal ion precipitation attached is used as an anode to perform an electrochemically mediated amine regeneration reaction on the rich liquid to desorb carbon dioxide; S4: The carbon dioxide generated in the electrolytic cell is collected, and after the carbon dioxide in the rich liquid is completely desorbed, the generated lean liquid is transported to the absorption tower to repeatedly absorb the carbon dioxide in the intermediate flue gas.

[0009] The electrochemical carbon capture flue gas purification method of the embodiment of the present invention can collect metal ions in the flue gas and use them in the desorption process of carbon dioxide, reduce the consumption of electrodes in the electrochemical mediated amine regeneration carbon dioxide capture process, and thus reduce the production cost of electrochemical mediated amine regeneration carbon dioxide capture.

[0010] In some embodiments, the present invention comprises a first electrolytic cell and a second electrolytic cell, wherein the first electrolytic cell has a first electrode and a second electrode, and the second electrolytic cell has a third electrode and a fourth electrode. In step S2, the first electrolytic cell is connected to a washing tower, wherein the first electrode is an anode and the second electrode is a cathode, and the second electrolytic cell is connected to an absorption tower, wherein the third electrode is an anode and the fourth electrode is a cathode; in step S3, the first electrolytic cell is connected to an absorption tower, wherein the first electrode is a cathode and the second electrode is an anode, and the second electrolytic cell is connected to a washing tower, wherein the third electrode is a cathode and the fourth electrode is an anode.

[0011] In some embodiments, in step S1, the flue gas to be treated in the washing tower flows from bottom to top, and the washing liquid flows from top to bottom, and / or, in step S3, the intermediate flue gas in the absorption tower flows from bottom to top, and the absorbent flows from top to bottom.

[0012] In some embodiments, the electrolytic cell is provided with an exhaust pipe, and the exhaust pipe is provided with an exhaust valve. In step S2, the exhaust valve is opened to collect oxygen and hydrogen generated in the electrolytic cell respectively. In step S4, the exhaust valve is opened to collect the generated carbon dioxide through the exhaust pipe.

[0013] The electrochemical carbon capture flue gas purification system of the embodiment of the present invention is based on the electrochemical carbon capture flue gas purification method of any of the above embodiments, comprising: A scrubbing tower and an absorption tower, wherein the scrubbing tower is connected with a smoke inlet pipe, a first smoke exhaust pipe, a first liquid drain pipe and a first liquid inlet pipe, wherein the smoke inlet pipe is used to transport the smoke to be treated, wherein the first smoke exhaust pipe is used to transport the washed intermediate smoke to the absorption tower, wherein the absorption tower is connected with a second smoke exhaust pipe, a second liquid drain pipe and a second liquid inlet pipe, wherein the second smoke exhaust pipe is used to discharge the smoke after carbon capture; An electrolytic cell, wherein the electrolytic cell is provided with a first port and a second port, and the electrolytic cell is provided with two electrodes corresponding to the first port and the second port, respectively. The electrolytic cell has a first connection position and a second connection position. At the first connection position, the first port is connected to the first liquid discharge pipe, and the second port is connected to the first liquid inlet pipe, and the electrode corresponding to the first port is an anode, and the electrode corresponding to the second port is a cathode; at the second connection position, the first port is connected to the second liquid inlet pipe, and the second port is connected to the second liquid discharge pipe, and the electrode corresponding to the first port is a cathode, and the electrode corresponding to the second port is an anode.

[0014] In some embodiments, an adjustment component is included, the adjustment component includes an annular base frame, the absorption tower is arranged in the middle of the base frame, the electrolytic cell is arranged on the base frame in an adjustable position along the extension direction of the base frame, the first connection position and the second connection position are arranged on the base frame and symmetrically on both radial sides of the absorption tower.

[0015] In some embodiments, the purification system comprises a first electrolytic cell and a second electrolytic cell, and has a first operating state and a second operating state. In the first operating state, the first electrolytic cell is connected to the first connection position, and the second electrolytic cell is connected to the second connection position. In the second operating state, the first electrolytic cell is connected to the second connection position, and the second electrolytic cell is connected to the first connection position.

[0016] In some embodiments, the base frame has a T-shaped cross-section and includes a cylinder supported on the ground and a support ring fixed to the end of the cylinder, the adjustment assembly includes a slide and a driving member, the slide is slidably mounted on the support ring, and the driving member is disposed on the slide and is used to drive the slide to move along the support ring.

[0017] In some embodiments, the first liquid discharge pipe is provided with a first valve, the first liquid inlet pipe is provided with a first pump and a second valve, the second liquid discharge pipe is provided with a third valve, and the second liquid inlet pipe is provided with a second pump and a fourth valve.

[0018] In some embodiments, the electrolyzer is provided with a first tube, a second tube and a third tube, the first tube is used to discharge hydrogen, the second tube is used to discharge oxygen, the third tube is used to discharge carbon dioxide, and the first tube, the second tube and the third tube are all provided with exhaust valves that can be opened and closed. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the connection of the electrochemical carbon capture flue gas purification system according to an embodiment of the present invention.

[0020] Figure 2It is a top view of the connection of the electrochemical carbon capture flue gas purification system according to an embodiment of the present invention.

[0021] Figure 3 It is a schematic diagram of the structure of the regulating component in the electrochemical carbon capture flue gas purification system of an embodiment of the present invention.

[0022] Reference numerals: Washing tower 1; smoke inlet pipe 11; first smoke exhaust pipe 12; first liquid discharge pipe 13; first liquid inlet pipe 14; Absorption tower 2; second smoke exhaust pipe 21; second liquid discharge pipe 22; second liquid inlet pipe 23; Adjustment assembly 3; base frame 31; cylinder 311; support ring 312; slide 32; drive member 33; First electrolytic cell 4; first electrode 41; second electrode 42; Second electrolytic cell 5 ; third electrode 51 ; fourth electrode 52 . DETAILED DESCRIPTION

[0023] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0024] The electrochemical carbon capture flue gas purification method of the embodiment of the present invention comprises the following steps: S1: The flue gas to be treated is passed into a scrubbing tower, the metal ions in the flue gas are absorbed by the scrubbing liquid, and the intermediate flue gas generated after being washed by the scrubbing tower is passed into an absorption tower; S2: passing the washing liquid that absorbs metal ions into the electrolytic cell, connecting the electrolytic cell to a power source for an electrodeposition reaction, so that the metal ions (such as Ni+, Pb2+, Cu2+) in the washing liquid can obtain electrons to generate solid metals through electrodeposition, and the solid metal precipitates are attached to the cathode of the electrolytic cell. After the metal ions are completely precipitated, the washing liquid in the electrolytic cell is passed into a washing tower to empty the liquid in the electrolytic cell; S3: The absorbent in the absorption tower reacts with the intermediate flue gas to absorb carbon dioxide to generate rich liquid, and the rich liquid is passed into the electrolytic cell, and the electrode with metal ion precipitation attached is used as the anode. The solid metal attached to the electrode replaces the electrode itself to participate in the electrochemical mediated amine regeneration reaction, and then the rich liquid is desorbed to release carbon dioxide. At the same time, the complex generated by the solid metal and the rich liquid undergoes a reduction reaction at the cathode of the electrolytic cell, and the metal solid is regenerated and attached to the cathode of the electrolytic cell; S4: The carbon dioxide generated in the electrolytic cell is collected, and after the carbon dioxide in the rich liquid is completely desorbed, the rich liquid becomes a lean liquid, and the generated lean liquid is transported to the absorption tower to repeatedly absorb the carbon dioxide in the intermediate flue gas.

[0025] The electrochemical carbon capture flue gas purification method of the embodiment of the present invention can collect metal ions in the flue gas and use them in the desorption process of carbon dioxide, reduce the consumption of electrodes in the electrochemical mediated amine regeneration carbon dioxide capture process, and thus reduce the production cost of electrochemical mediated amine regeneration carbon dioxide capture.

[0026] Optionally, the metal ions are copper ions, and the absorbent is a monoethanolamine (MEA) solution. When the electrolytic cell is connected to the scrubber, the copper ions react at the cathode of the electrolytic cell to generate copper element through an electrodeposition reaction. When the electrolytic cell is connected to the absorption tower to analyze carbon dioxide, in the anode tank: copper (Cu) element dissolves into the solution and forms a Cu(II)-MEA complex with MEA. In this process, copper metal is oxidized to generate copper ions, and at the same time forms a complex with MEA to release CO2. The specific chemical reaction is: Cu(s)+2nAmine(CO2)n(aq)→CuAm2 2+ (aq)+2CO2(g)+2e−; In the cathode tank: Cu(II)-MEA complex undergoes a reduction reaction, Cu(II) is reduced to elemental copper and deposited on the cathode, and MEA is regenerated at the same time. The specific chemical reaction is: CuAm2 2+ (aq)+2e−→Cu(s)+2nAmine(aq).

[0027] In some embodiments, the present invention comprises a first electrolytic cell and a second electrolytic cell, wherein the first electrolytic cell has a first electrode and a second electrode, and the second electrolytic cell has a third electrode and a fourth electrode. In step S2, the first electrolytic cell is connected to a washing tower, wherein the first electrode is an anode and the second electrode is a cathode, and the second electrolytic cell is connected to an absorption tower, wherein the third electrode is an anode and the fourth electrode is a cathode; in step S3, the first electrolytic cell is connected to an absorption tower, wherein the first electrode is a cathode and the second electrode is an anode, and the second electrolytic cell is connected to a washing tower, wherein the third electrode is a cathode and the fourth electrode is an anode.

[0028] By arranging the first electrolytic cell and the second electrolytic cell, the electrodeposition reaction of the metal ions in the washing liquid and the electrochemically mediated amine regeneration reaction in the absorbent can be carried out simultaneously, and by exchanging the positions of the first electrolytic cell and the second electrolytic cell, the collection of the metal ions in the flue gas is ensured, and the collected ions are allowed to quickly participate in the electrochemically mediated amine regeneration reaction, thereby improving the production continuity of the entire carbon capture system and further improving the carbon dioxide collection efficiency of the carbon capture system.

[0029] In some embodiments, in step S1, the flue gas to be treated in the washing tower flows from bottom to top, and the washing liquid flows from top to bottom. By making the washing liquid and the flue gas to be treated flow in relative counter-currents, the adsorption efficiency of the washing liquid on metal ions in the flue gas to be treated is improved, thereby ensuring the filtering effect of the flue gas to be treated.

[0030] In some embodiments, in step S3, the intermediate flue gas in the absorption tower flows from bottom to top, and the absorbent flows from top to bottom. By making the absorbent and the intermediate flue gas flow in relative counter-currents, the reaction efficiency of the absorbent and the carbon dioxide in the intermediate flue gas is improved, thereby ensuring the capture efficiency of carbon dioxide.

[0031] In some embodiments, an exhaust pipe is provided on the electrolytic cell, and an exhaust valve is provided on the exhaust pipe. In step S2, the exhaust valve is opened to collect oxygen and hydrogen generated in the electrolytic cell respectively. In step S4, the exhaust valve is opened to collect the generated carbon dioxide through the exhaust pipe.

[0032] By setting an exhaust valve, the opening and closing of the exhaust pipe can be controlled, thereby preventing the gas generated in the electrolytic cell from leaking into the atmosphere. At the same time, the exhaust pipe can be set to collect the generated gases separately. While ensuring the efficiency of carbon capture, the hydrogen and oxygen generated by electrodeposition can be recycled to reduce production costs.

[0033] The following describes an electrochemical carbon capture flue gas purification system according to an embodiment of the present invention.

[0034] like Figure 1 and Figure 2 As shown, the electrochemical carbon capture flue gas purification system of the embodiment of the present invention includes the electrochemical carbon capture flue gas purification method of any of the above embodiments, including a washing tower 1, an absorption tower 2 and an electrolyzer, the washing tower 1 is connected with a smoke inlet pipe 11, a first smoke exhaust pipe 12, a first liquid discharge pipe 13 and a first liquid inlet pipe 14, the smoke inlet pipe 11 is used to transport the smoke to be treated, the first smoke exhaust pipe 12 is used to transport the intermediate smoke after washing to the absorption tower 2, the first liquid discharge pipe 13 and the first liquid inlet pipe 14 are used to transport the washing liquid, the absorption tower 2 is connected with a second smoke exhaust pipe 21, a second liquid discharge pipe 22 and a second liquid inlet pipe 23, the second smoke exhaust pipe 21 is used to discharge The flue gas after carbon capture is released, and the second discharge pipe 22 and the second inlet pipe 23 are used to transport the absorbent. The electrolytic cell is provided with a first port and a second port, and the electrolytic cell is provided with two electrodes corresponding to the first port and the second port respectively. The electrolytic cell has a first connection position and a second connection position. At the first connection position, the first port is connected to the first discharge pipe 13, and the second port is connected to the first inlet pipe 14. The electrode corresponding to the first port is an anode, and the electrode corresponding to the second port is a cathode; at the second connection position, the first port is connected to the second inlet pipe 23, and the second port is connected to the second discharge pipe 22. The electrode corresponding to the first port is a cathode, and the electrode corresponding to the second port is an anode.

[0035] When the electrochemical carbon capture flue gas purification system of the embodiment of the present invention is in use, the flue gas to be treated enters the washing tower 1 through the smoke inlet pipe 11, the flue gas to be treated is washed by the washing liquid to generate intermediate flue gas, the intermediate flue gas enters the absorption tower 2 through the first smoke exhaust pipe 12, the washing liquid absorbs the metal ions in the flue gas and gathers at the bottom of the washing tower 1, the electrolytic cell is connected to the first connection position, and the washing liquid absorbing the metal ions is transported to the electrolytic cell through the first liquid discharge pipe 13 and the first port, the electrode corresponding to the first port is used as the anode, and the electrode corresponding to the second port is used as the cathode, the electrolytic cell is subjected to an electrodeposition reaction, so that the metal ions obtain electrons at the cathode to generate metal elements, and when the metal ions in the washing liquid in the electrolytic cell are precipitated, the washing liquid in the electrolytic cell is transported to the washing tower 1 through the second port and the first liquid inlet pipe 14; The electrolytic cell is connected to the second connection position, and the intermediate flue gas entering the absorption tower 2 is discharged from the absorption tower 2 after reacting with the flowing absorbent. The absorbent generates rich liquid by capturing the carbon dioxide in the intermediate flue gas. The rich liquid gathers at the bottom of the absorption tower 2 and enters the electrolytic cell through the second liquid discharge pipe 22 and the second port. The electrode attached with metal ion precipitation is used as the anode, and the solid metal attached to the electrode replaces the electrode itself to participate in the electrochemically mediated amine regeneration reaction, thereby desorbing the rich liquid and releasing carbon dioxide. At the same time, the complex generated by the solid metal and the rich liquid undergoes a reduction reaction at the cathode of the electrolytic cell, regenerating metal solid and attaching to the cathode of the electrolytic cell, and collecting the carbon dioxide generated in the electrolytic cell. After the carbon dioxide in the rich liquid is completely desorbed, the rich liquid becomes a lean liquid, and the generated lean liquid is transported to the absorption tower 2 through the second liquid inlet pipe 23 and the first port, so that the absorbent repeatedly captures and absorbs the carbon dioxide in the intermediate flue gas.

[0036] It should be noted that when the electrolytic cell is connected to the first connection position, the reaction time of the electrodeposition in the electrolytic cell can be adjusted according to the metal element attached to the cathode in the electrolytic cell. When the electrolytic cell is connected to the second connection position, the reaction time of the electrochemically mediated amine reaction in the electrolytic cell can be adjusted according to the consumption of the metal element attached to the anode in the electrolytic cell.

[0037] The electrochemical carbon capture flue gas purification system of the embodiment of the present invention can collect metal ions in the flue gas and use them in the desorption process of carbon dioxide, reducing the consumption of electrodes in the electrochemical mediated amine regeneration carbon dioxide capture process, thereby reducing the production cost of electrochemical mediated amine regeneration carbon dioxide capture.

[0038] In some embodiments, Figure 2 and Figure 3As shown, it includes an adjustment component 3, which includes a ring-shaped base frame 31. The absorption tower 2 is arranged in the middle of the base frame 31, and the electrolytic cell is arranged on the base frame 31 in an adjustable position along the extension direction of the base frame 31. The first connection position and the second connection position are arranged on the base frame 31 and are symmetrically arranged on both radial sides of the absorption tower 2.

[0039] Specifically, the washing tower 1 and the absorption tower 2 are fixedly connected to the base frame 31, and the first liquid discharge pipe 13, the first liquid inlet pipe 14, the second liquid discharge pipe 22, and the second liquid inlet pipe 23 are fixedly connected to the base frame 31. The base frame 31 is set, and the electrolytic cell is moved on the base frame 31, so that the electrolytic cell can be quickly adjusted between the first connection position and the second connection position, thereby reducing the difficulty of connecting and disassembling the electrolytic cell with the washing tower 1 and the absorption tower 2 respectively, and improving the carbon capture efficiency of the electrochemical carbon capture flue gas purification system.

[0040] In some embodiments, Figure 1 and Figure 2 As shown, the purification system includes a first electrolytic cell 4 and a second electrolytic cell 5, and has a first operating state and a second operating state. In the first operating state, the first electrolytic cell 4 is connected to the first connection position, and the second electrolytic cell 5 is connected to the second connection position. In the second operating state, the first electrolytic cell 4 is connected to the second connection position, and the second electrolytic cell 5 is connected to the first connection position.

[0041] Specifically, the first electrolytic cell 4 has a first electrode 41 and a second electrode 42, and the second electrolytic cell 5 has a third electrode 51 and a fourth electrode 52. In a first operating state, the first electrolytic cell 4 is connected to the washing tower 1, the first electrode 41 is an anode, and the second electrode 42 is a cathode, and the second electrolytic cell 5 is connected to the absorption tower 2, the third electrode 51 is an anode, and the fourth electrode 52 is a cathode; in a second operating state, the first electrolytic cell 4 is connected to the absorption tower 2, the first electrode 41 is a cathode, and the second electrode 42 is an anode, and the second electrolytic cell 5 is connected to the washing tower 1, the third electrode 51 is a cathode, and the fourth electrode 52 is an anode.

[0042] By setting the first electrolytic cell 4 and the second electrolytic cell 5, in the first operating state, the first electrolytic cell 4 and the second electrolytic cell 5 operate simultaneously, thereby ensuring the continuity of the operation of the electrochemical carbon capture flue gas purification system, and the purification system can be adjusted to the second operating state, that is, the first electrolytic cell 4 and the second connecting cell 5 are adjusted between the first connecting position and the second connecting position, thereby simultaneously realizing the collection of metal ions in the flue gas and the desorption of carbon dioxide by using the collected metal element as an anode reactant, thereby improving the collection efficiency of metal ions in the flue gas and the carbon capture efficiency of carbon dioxide, and improving the overall operating efficiency of the electrochemical carbon capture flue gas purification system.

[0043] In some embodiments, Figure 3As shown, the base frame 31 has a T-shaped cross-section and includes a cylinder 311 supported on the ground and a support ring 312 fixed to the end of the cylinder 311. The adjustment component 3 includes a slide 32 and a driving member 33. The slide 32 is slidably mounted on the support ring 312. The driving member 33 is arranged on the slide 32 and is used to drive the slide 32 to move along the support ring 312.

[0044] Specifically, a ring gear is coaxially fixed on the support ring 312, and the driving member 33 includes a driving motor and a driving gear. The driving motor is fixed on the slide 32, and the driving gear is fixed on the output shaft of the driving motor and meshes with the ring gear for transmission. The driving motor drives the driving gear to rotate, and the driving gear meshes with the ring gear for transmission and then drives the slide 32 to rotate, thereby realizing the adjustment of the position of the electrolytic cell. The operation is convenient, safe and reliable.

[0045] In some embodiments, the first liquid discharge pipe 13 is provided with a first valve, the first liquid inlet pipe 14 is provided with a first pump and a second valve, the second liquid discharge pipe 22 is provided with a third valve, and the second liquid inlet pipe 23 is provided with a second pump and a fourth valve.

[0046] When the electrolytic cell is connected to the first connection position, the first valve can be opened to allow the washing liquid in the washing tower 1 to enter the electrolytic cell through the first liquid discharge pipe 13, and the first valve and the second valve can be closed to prevent the gas generated in the electrolytic cell from leaking through the first liquid discharge pipe 13 and the first liquid inlet pipe 14. At the same time, after the metal ions in the washing liquid in the electrolytic cell are precipitated, the second valve and the first pump can be opened to transport all the washing liquid in the electrolytic cell to the washing tower 1. When the electrolytic cell is connected to the second connection position, the third valve can be opened to allow the absorbent in the absorption tower 2 to enter the electrolytic cell through the second liquid discharge pipe 22, and the third valve and the fourth valve can be closed to prevent the gas generated in the electrolytic cell from leaking through the second liquid discharge pipe 22 and the second liquid inlet pipe 23. At the same time, after the rich liquid in the electrolytic cell completely undergoes an electrochemically mediated amine reaction, the fourth valve and the second pump can be opened to transport all the lean liquid in the electrolytic cell to the absorption tower 2.

[0047] In some embodiments, the electrolyzer is provided with a first tube, a second tube and a third tube, the first tube is used to discharge hydrogen, the second tube is used to discharge oxygen, and the third tube is used to discharge carbon dioxide, and the first tube, the second tube and the third tube are all provided with exhaust valves that can be opened and closed.

[0048] By providing the first tube, the second tube and the third tube, it is convenient to connect with the gas delivery pipeline for collecting hydrogen, oxygen and carbon dioxide, thereby avoiding leakage of the gas generated in the electrolytic cell. At the same time, the generated gas can be classified and collected to ensure the purity of the collected gas.

[0049] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0050] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0053] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0054] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An electrochemical carbon capture flue gas purification method, characterized in that: The following steps are involved: S1: The flue gas to be treated is passed into a scrubbing tower, the metal ions in the flue gas are absorbed by the scrubbing liquid, and the intermediate flue gas generated after being scrubbed by the scrubbing tower is passed into an absorption tower; S2: passing the washing liquid that absorbs metal ions into the electrolytic cell, precipitating the metal ions in the washing liquid onto the cathode of the electrolytic cell through electrodeposition, and passing the washing liquid in the electrolytic cell into the washing tower after the metal ions are completely precipitated; S3: The absorbent in the absorption tower reacts with the intermediate flue gas to absorb carbon dioxide to generate a rich liquid, which is passed into the electrolytic cell, and an electrode with metal ion precipitation attached is used as an anode to perform an electrochemically mediated amine regeneration reaction on the rich liquid to desorb carbon dioxide; S4: The carbon dioxide generated in the electrolytic cell is collected, and after the carbon dioxide in the rich liquid is completely desorbed, the generated lean liquid is transported to the absorption tower to repeatedly absorb the carbon dioxide in the intermediate flue gas.

2. The electrochemical carbon capture flue gas purification method according to claim 1, characterized in that: The method comprises a first electrolytic cell and a second electrolytic cell, wherein the first electrolytic cell has a first electrode and a second electrode, and the second electrolytic cell has a third electrode and a fourth electrode. In step S2, the first electrolytic cell is connected to a washing tower, the first electrode is an anode, the second electrode is a cathode, the second electrolytic cell is connected to an absorption tower, the third electrode is an anode, and the fourth electrode is a cathode; in step S3, the first electrolytic cell is connected to an absorption tower, the first electrode is a cathode, the second electrode is an anode, the second electrolytic cell is connected to a washing tower, the third electrode is a cathode, and the fourth electrode is an anode.

3. The electrochemical carbon capture flue gas purification method according to claim 1, characterized in that: In step S1, the flue gas to be treated in the scrubbing tower flows from bottom to top, and the scrubbing liquid flows from top to bottom, and / or, in step S3, the intermediate flue gas in the absorption tower flows from bottom to top, and the absorbent flows from top to bottom.

4. The electrochemical carbon capture flue gas purification method according to claim 1, characterized in that: The electrolytic cell is provided with an exhaust pipe, and the exhaust pipe is provided with an exhaust valve. In step S2, the exhaust valve is opened to collect oxygen and hydrogen generated in the electrolytic cell respectively. In step S4, the exhaust valve is opened to collect the generated carbon dioxide through the exhaust pipe.

5. An electrochemical carbon capture flue gas purification system, characterized in that: include: A scrubbing tower and an absorption tower, wherein the scrubbing tower is connected with a smoke inlet pipe, a first smoke exhaust pipe, a first liquid drain pipe and a first liquid inlet pipe, wherein the smoke inlet pipe is used to transport the smoke to be treated, wherein the first smoke exhaust pipe is used to transport the washed intermediate smoke to the absorption tower, wherein the absorption tower is connected with a second smoke exhaust pipe, a second liquid drain pipe and a second liquid inlet pipe, wherein the second smoke exhaust pipe is used to discharge the smoke after carbon capture; An electrolytic cell, wherein the electrolytic cell is provided with a first port and a second port, and the electrolytic cell is provided with two electrodes corresponding to the first port and the second port, respectively. The electrolytic cell has a first connection position and a second connection position. At the first connection position, the first port is connected to the first liquid discharge pipe, and the second port is connected to the first liquid inlet pipe, and the electrode corresponding to the first port is an anode, and the electrode corresponding to the second port is a cathode; at the second connection position, the first port is connected to the second liquid inlet pipe, and the second port is connected to the second liquid discharge pipe, and the electrode corresponding to the first port is a cathode, and the electrode corresponding to the second port is an anode.

6. The electrochemical carbon capture flue gas purification system according to claim 5, characterized in that: It includes an adjustment component, which includes an annular base frame, the absorption tower is arranged in the middle of the base frame, the electrolytic cell is arranged on the base frame in an adjustable position along the extension direction of the base frame, and the first connection position and the second connection position are arranged on the base frame and symmetrically on the radial sides of the absorption tower.

7. The electrochemical carbon capture flue gas purification system according to claim 6, characterized in that: The purification system comprises a first electrolytic cell and a second electrolytic cell, and has a first operating state and a second operating state. In the first operating state, the first electrolytic cell is connected to the first connection position, and the second electrolytic cell is connected to the second connection position. In the second operating state, the first electrolytic cell is connected to the second connection position, and the second electrolytic cell is connected to the first connection position.

8. The electrochemical carbon capture flue gas purification system according to claim 6, characterized in that: The base frame has a T-shaped cross-section and includes a cylinder supported on the ground and a support ring fixed to the end of the cylinder. The adjustment assembly includes a slide and a drive member. The slide is slidably mounted on the support ring. The drive member is arranged on the slide and is used to drive the slide to move along the support ring.

9. The electrochemical carbon capture flue gas purification system according to claim 5, characterized in that: The first liquid discharge pipe is provided with a first valve, the first liquid inlet pipe is provided with a first pump and a second valve, the second liquid discharge pipe is provided with a third valve, and the second liquid inlet pipe is provided with a second pump and a fourth valve.

10. The electrochemical carbon capture flue gas purification system according to claim 5, characterized in that: The electrolytic cell is provided with a first tube, a second tube and a third tube, the first tube is used to discharge hydrogen, the second tube is used to discharge oxygen, the third tube is used to discharge carbon dioxide, and the first tube, the second tube and the third tube are all provided with exhaust valves that can be opened and closed.

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