Carbon dioxide capture system and control method therefor

Abstract

The present application relates to the technical field of environmental protection, and discloses a carbon dioxide capture system and a control method therefor. In the system, an absorption tower has a bottom section divided into a first chamber and a second chamber, an absorption liquid first flows into the first chamber and then overflows from the first chamber into the second chamber via the top of the second chamber, and the second chamber is configured to perform phase-separation on the absorption liquid; a light phase outlet and a heavy phase outlet are formed in a shell of the absorption tower, the light phase outlet communicates with an inlet of an absorbent mixing unit through a first conveying pipeline, and the light phase outlet communicates with a first inlet of a heat exchange unit through a second conveying pipeline; the heavy phase outlet communicates with the inlet of the absorbent mixing unit through a third conveying pipeline, and the heavy phase outlet communicates with the first inlet of the heat exchange unit through a fourth conveying pipeline; and a second outlet of the heat exchange unit communicates with the inlet of the absorbent mixing unit, and an outlet of the absorbent mixing unit communicates with an absorbent inlet of the absorption tower. The carbon dioxide capture system of the present application can accommodate both a single-phase scenario and various phase-separation scenarios, and has a high flexibility.

Description

CARBON DIOXIDE CAPTURE SYSTEM AND CONTROL METHOD THEREFOR  Cross Reference to Related ApplicationsThis application claims the benefit of Chinese Patent Application No. 202411678476.0, filed on November 22, 2024, the contents of which are incorporated herein by reference. Field of the InventionThe present application relates to the technical field of environmental protection, in particular to a carbon dioxide capture system and a control method for the carbon dioxide capture system. Background of the InventionIn order to reduce carbon dioxide emissions to alleviate the greenhouse effect, various carbon dioxide capture technologies have emerged. A carbon dioxide capture technology based on a phase-change absorbent is one of the commonly used carbon dioxide capture technologies at present. The principle of the carbon dioxide capture technology is that after absorbing carbon dioxide, the phase-change absorbent forms two immiscible liquid phases, namely a CO2-lean phase and a CO2-rich phase, wherein the concentration of carbon dioxide in the CO2-lean phase is lower than that of carbon dioxide in the CO2-rich phase, the CO2-lean phase and the CO2-rich phase are separated, and the CO2-rich phase is conveyed to a regenerator for carbon dioxide desorption.In the case of different formulations of the phase-change absorbent, e.g., different phase separating agents in the phase-change absorbent, two phase-separation scenarios generally occur: the CO2-lean phase is a heavy phase and the CO2-rich phase is a light phase; or, the CO2-lean phase is a light phase and the CO2-rich phase is a heavy phase. In the same phase-change absorbent formulation, the above two phase-separation scenarios may also occur due to the influence of the flue gas flow rate, carbon dioxide concentration in flue gas, impurities in flue gas, the absorption temperature and so on. Moreover, continuous switching between the two phase-separation scenarios may occur during the operation.However, existing carbon dioxide capture systems are typically designed for only one phase-separation scenario and cannot accommodate various phase-separation scenarios, not to mention the switching phase-separation scenarios. For example, in a carbon dioxide capture system designed for the scenario that the CO2-lean phase is a heavy phase and the CO2-rich phase is a light phase, the light phase, namely the CO2-rich phase, is typically fixedly conveyed to the regenerator for carbon dioxide desorption, and the carbon dioxide capture system cannot convey the heavy phase, namely the CO2-rich phase, to the regenerator for carbon dioxide desorption when the phase-separation scenario changes, for example, the phase-separation scenario changes to the scenario that the CO2-lean phase is a light phase and the CO2-rich phase is a heavy phase. Summary of the InventionAn object of the present application is to provide a carbon dioxide capture system and a control method therefor in order to solve the problem in the prior art that a carbon dioxide capture system cannot accommodate various phase-separation scenarios.In order to achieve the above object, a first aspect of the present application provides a carbon dioxide capture system, including an absorption tower, a first carbon dioxide detection device, a second carbon dioxide detection device, a first conveying pipeline, a second conveying pipeline, a third conveying pipeline, a fourth conveying pipeline, an absorbent mixing unit, a heat exchange unit, and a regenerator;the absorption tower has a bottom section divided into a first chamber and a second chamber by a partition assembly, an absorption liquid first flows into the first chamber and then overflows from the first chamber to the second chamber via the top of the second chamber, and the second chamber is configured to perform phase-separation on the inflowing absorption liquid;a shell of the absorption tower corresponding to the second chamber is provided with a light phase outlet for discharging a light phase solution and a heavy phase outlet for discharging a heavy phase solution, and the light phase solution has a density less than that of the heavy phase solution; the first carbon dioxide detection device is configured to detect parameters related to the carbon dioxide content in the light phase solution, and the second carbon dioxide detection device is configured to detect parameters related to the carbon dioxide content in the heavy phase solution;the light phase outlet communicates with an inlet of the absorbent mixing unit through the first conveying pipeline, and the light phase outlet communicates with a first inlet of the heat exchange unit through the second conveying pipeline; the heavy phase outlet communicates with the inlet of the absorbent mixing unit through the third conveying pipeline, and the heavy phase outlet communicates with the first inlet of the heat exchange unit through the fourth conveying pipeline; anda first outlet of the heat exchange unit communicates with an inlet of the regenerator, and a second inlet of the heat exchange unit communicates with the bottom section of the regenerator; a second outlet of the heat exchange unit communicates with the inlet of the absorbent mixing unit, and an outlet of the absorbent mixing unit communicates with an absorbent inlet of the absorption tower.In an embodiment of the present application, the bottom of the first chamber is provided with a first outlet, and the carbon dioxide capture system further includes a fifth conveying pipeline; andthe first outlet of the first chamber communicates with the first inlet of the heat exchange unit through the fifth conveying pipeline.In an embodiment of the present application, the bottom of the first chamber is further provided with a second outlet, the bottom of the second chamber is provided with a third outlet, and the carbon dioxide capture system further includes a sixth conveying pipeline; andthe second outlet of the first chamber communicates with the third outlet of the second chamber through the sixth conveying pipeline.In an embodiment of the present application, the shell of the absorption tower corresponding to the second chamber is further provided with an interface detection device.In an embodiment of the present application, the absorption tower includes a packing section and a bottom section, the bottom section having a diameter greater than that of the packing section.In an embodiment of the present application, the partition assembly includes a first baffle and a second baffle;the first baffle extends from a base of the bottom section of the absorption tower to a packing section of the absorption tower for dividing the bottom section of the absorption tower into the first chamber and the second chamber;the second baffle extends from the shell of the absorption tower corresponding to the top of the second chamber to the top of the first chamber for covering the top of the second chamber; anda flow passage for the absorption liquid is defined between the first baffle and the second baffle.In an embodiment of the present application, a phase-separation device is further disposed in the second chamber.In an embodiment of the present application, the heat exchange unit includes a first heat exchanger and a second heat exchanger;the light phase outlet communicates with a first inlet of the first heat exchanger through the second conveying pipeline, the heavy phase outlet communicates with the first inlet of the first heat exchanger through the fourth conveying pipeline, and the first outlet of the first chamber communicates with the first inlet of the first heat exchanger and a first inlet of the second heat exchanger through the fifth conveying pipeline;both a first outlet of the first heat exchanger and a first outlet of the second heat exchanger communicate with the inlet of the regenerator, and both a second inlet of the first heat exchanger and a second inlet of the second heat exchanger communicate with the bottom section of the regenerator; andboth a second outlet of the first heat exchanger and a second outlet of the second heat exchanger communicate with the inlet of the absorbent mixing unit.In an embodiment of the present application, the absorbent mixing unit includes a first mixer and a second mixer;the light phase outlet communicates with an inlet of the first mixer through the first conveying pipeline, and the heavy phase outlet communicates with an inlet of the second mixer through the third conveying pipeline; andthe second outlet of the first heat exchanger communicates with both the inlet of the first mixer and the inlet of the second mixer, and the second outlet of the second heat exchanger communicates with both the inlet of the first mixer and the inlet of the second mixer.In an embodiment of the present application, a first flow meter and a first flow regulating valve are disposed on the second conveying pipeline; anda second flow meter and a second flow regulating valve are disposed on the fourth conveying pipeline.In an embodiment of the present application, a liquid level detection device is disposed on a shell of the absorption tower corresponding to the first chamber, and a third flow meter and a third flow regulating valve are disposed on the fifth conveying pipeline.A second aspect of the present application provides a control method for the carbon dioxide capture system described above, including:in response to the carbon dioxide content in a light phase solution being less than that in a heavy phase solution, opening a first conveying pipeline, closing a second conveying pipeline, and controlling the light phase solution to be conveyed to an absorbent mixing unit via the first conveying pipeline; and closing a third conveying pipeline, opening a fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to a heat exchange unit via the fourth conveying pipeline; andin response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, closing the first conveying pipeline, opening the second conveying pipeline, and controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline; and opening the third conveying pipeline, closing the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline.A third aspect of the present application provides a control method for the above carbon dioxide capture system, wherein the bottom of a first chamber is provided with a first outlet, the carbon dioxide capture system further includes a fifth conveying pipeline, the first outlet of the first chamber communicates with a first inlet of a heat exchange unit through the fifth conveying pipeline, and the control method includes:in response to the carbon dioxide content in a light phase solution being less than that in a heavy phase solution, opening a first conveying pipeline, closing a second conveying pipeline, and controlling the light phase solution to be conveyed to an absorbent mixing unit via the first conveying pipeline; and closing a third conveying pipeline, opening a fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline;in response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, closing the first conveying pipeline, opening the second conveying pipeline, and controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline; and opening the third conveying pipeline, closing the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline; andin response to an absorbent being a single-phase absorbent, closing the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline, opening the fifth conveying pipeline, and controlling the solution in the first chamber to be conveyed to the heat exchange unit.In an embodiment of the present application, the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer;controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline includes:controlling the light phase solution to be conveyed to the first mixer via the first conveying pipeline;controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline includes:controlling the heavy phase solution to be conveyed to the first heat exchanger via the fourth conveying pipeline;controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline includes:controlling the light phase solution to be conveyed to the first heat exchanger via the second conveying pipeline;controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline includes:controlling the heavy phase solution to be conveyed to the second mixer via the third conveying pipeline; andcontrolling the solution in the first chamber to be conveyed to the heat exchange unit includes:controlling the solution in the first chamber to be conveyed to the first heat exchanger and the second heat exchanger.A fourth aspect of the present application provides a control method for the above carbon dioxide capture system, wherein the bottom of a first chamber is provided with a first outlet and a second outlet, the bottom of a second chamber is provided with a third outlet, and the carbon dioxide capture system further includes a fifth conveying pipeline and a sixth conveying pipeline; the first outlet of the first chamber communicates with a first inlet of a heat exchange unit through the fifth conveying pipeline, and the second outlet of the first chamber communicates with the third outlet of the second chamber through the sixth conveying pipeline, and the control method includes:in response to the carbon dioxide content in a light phase solution being less than that in a heavy phase solution, opening a first conveying pipeline, closing a second conveying pipeline, and controlling the light phase solution to be conveyed to an absorbent mixing unit via the first conveying pipeline; and closing a third conveying pipeline, opening a fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline;in response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, closing the first conveying pipeline, opening the second conveying pipeline, and controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline; and opening the third conveying pipeline, closing the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline;in response to an absorbent being a single-phase absorbent, closing the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline, opening the fifth conveying pipeline, and controlling the solution in the first chamber to be conveyed to the heat exchange unit; andin response to the second chamber containing a single-phase absorption liquid, closing the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline, opening the fifth conveying pipeline and the sixth conveying pipeline, and controlling the solution in the bottom section of the absorption tower to be conveyed to the heat exchange unit.In an embodiment of the present application, the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer;controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline includes:controlling the light phase solution to be conveyed to the first mixer via the first conveying pipeline;controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline includes:controlling the heavy phase solution to be conveyed to the first heat exchanger via the fourth conveying pipeline;controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline includes:controlling the light phase solution to be conveyed to the first heat exchanger via the second conveying pipeline;controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline includes:controlling the heavy phase solution to be conveyed to the second mixer via the third conveying pipeline;controlling the solution in the first chamber to be conveyed to the heat exchange unit includes:controlling the solution in the first chamber to be conveyed to the first heat exchanger and the second heat exchanger; andcontrolling the solution in the bottom section of the absorption tower to be conveyed to the heat exchange unit includes:controlling the solution in the bottom section of the absorption tower to be conveyed to the first heat exchanger and the second heat exchanger.By the above technical solutions, the carbon dioxide capture system includes the absorption tower, the first carbon dioxide detection device, the second carbon dioxide detection device, the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, the fourth conveying pipeline, the absorbent mixing unit, the heat exchange unit and the regenerator; the bottom section of the absorption tower is divided into the first chamber and the second chamber by the partition assembly, the absorption liquid first flows into the first chamber and then overflows from the first chamber to the second chamber via the top of the second chamber, and the second chamber is configured to perform phase-separation on the inflowing absorption liquid; the shell of the absorption tower corresponding to the second chamber is provided with the light phase outlet for discharging the light phase solution and the heavy phase outlet for discharging the heavy phase solution, and the density of the light phase solution is less than that of the heavy phase solution; the first carbon dioxide detection device is configured to detect the parameters related to the carbon dioxide content in the light phase solution, and the second carbon dioxide detection device is configured to detect the parameters related to the carbon dioxide content in the heavy phase solution; the light phase outlet communicates with the inlet of the absorbent mixing unit through the first conveying pipeline, and the light phase outlet communicates with the first inlet of the heat exchange unit through the second conveying pipeline; the heavy phase outlet communicates with the inlet of the absorbent mixing unit through the third conveying pipeline, and the heavy phase outlet communicates with the first inlet of the heat exchange unit through the fourth conveying pipeline; and the first outlet of the heat exchange unit communicates with the inlet of the regenerator, and the second inlet of the heat exchange unit communicates with the bottom section of the regenerator; the second outlet of the heat exchange unit communicates with the inlet of the absorbent mixing unit, and the outlet of the absorbent mixing unit communicates with the absorbent inlet of the absorption tower. The carbon dioxide capture system provided in the embodiments of the present application is applicable regardless whether a CO2-lean phase is a heavy phase and a CO2-rich phase is a light phase, or the CO2-lean phase is a light phase and the CO2-rich phase is a heavy phase. That is, the carbon dioxide capture system provided in the embodiments of the present application can accommodate various phase-separation scenarios and has a high flexibility. When the phase-separation scenario changes, there is no need to replace equipment or make additional designs, so as to greatly reduce the equipment investment cost of the carbon dioxide capture system.Other features and advantages of the embodiments of the present application will be described in detail in the subsequent Detailed Description. Brief Description of DrawingsThe accompanying drawings are included to provide a further understanding of the embodiments of the present application and constitute a part of this specification, and together with the detailed description below serve to explain, but not to limit, the embodiments of the present application. In the drawings:FIG. 1 schematically shows a schematic structural diagram of a carbon dioxide capture system according to an embodiment of the present application;FIG. 2 schematically illustrates a schematic structural diagram of an absorption tower according to an embodiment of the present application;FIG. 3 schematically shows a schematic structural diagram of another carbon dioxide capture system according to an embodiment of the present application;FIG. 4 schematically illustrates a schematic control logic diagram of a mode 1 according to an embodiment of the present application;FIG. 5 schematically illustrates a schematic control logic diagram of a mode 2 according to an embodiment of the present application;FIG. 6 schematically illustrates a schematic control logic diagram of a mode 3 according to an embodiment of the present application; andFIG. 7 schematically illustrates a schematic control logic diagram of a mode 4 according to an embodiment of the present application.Description of reference numerals100-carbon dioxide capture system; 101-absorption tower; 1011-first chamber; 1012-second chamber; 1013-first baffle; 1014-second baffle; 1015-phase-separation device; 1016-interface detection device; 1017-viewing window; 1018-interface controller; 1019-liquid level detection device; 102-first carbon dioxide detection device; 103-second carbon dioxide detection device; 104-first conveying pipeline; 105-second conveying pipeline; 106-third conveying pipeline; 107-fourth conveying pipeline; 108-absorbent mixing unit; 1081-first mixer; 1082-second mixer; 109-heat exchange unit; 1091-first heat exchanger; 1092-second heat exchanger; 110-regenerator; 111-light phase pipeline; 112-heavy phase pipeline; 113-light-phase three-way valve; 114-heavy-phase three-way valve; 115-light phase pump; 116-heavy phase pump; 117-lean liquid cooler; 118-first flow meter; 119-first flow regulating valve; 120-second flow meter; 121-second flow regulating valve; 122-light-phase flow controller; 123-heavy-phase flow controller; 124-fifth conveying pipeline; 125-single-phase pump; 126-third flow meter; 127-third flow regulating valve; 128-liquid level controller; 129-single-phase flow controller; 130-sixth conveying pipeline; 131-on-off valve; 132-rich liquid main pipeline; 133-rich liquid three-way valve; 134-first rich liquid branch pipeline; 135-second rich liquid branch pipeline; 136-first lean liquid main pipeline; 137-first lean liquid three-way valve; 138-first lean liquid branch pipeline; 139-second lean liquid branch pipeline; 140-lean liquid pump; 141-second lean liquid main pipeline; 142-second lean liquid three-way valve; 143-third lean liquid branch pipeline; 144-fourth lean liquid branch pipeline; and 145-absorbent flow meter. Detailed Description of the EmbodimentsTo make the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. It should be understood that the specific implementations described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without inventive efforts belong to the scope of protection of the present application.If descriptions such as “first” and “second” are involved in the embodiments of the present application, the descriptions such as “first” and “second” are used for descriptive purposes only, and cannot be understood to indicate or imply relative importance thereof or to implicitly indicate the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the embodiments may be combined with each other, but must be on the premise that those skilled in the art can implement the same. When the combination of technical solutions contradicts each other or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed in the present application.As described in the background, in order to reduce carbon dioxide emissions to alleviate the greenhouse effect, various carbon dioxide capture technologies have emerged. A carbon dioxide capture technology based on a phase-change absorbent is one of the commonly used carbon dioxide capture technologies at present. A principle of the carbon dioxide capture technology is that after absorbing carbon dioxide, the phase-change absorbent forms two immiscible liquid phases, namely a CO2-lean phase and a CO2-rich phase, wherein the concentration of carbon dioxide in the CO2-lean phase is lower than that of carbon dioxide in the CO2-rich phase, the CO2-lean phase and the CO2-rich phase are separated, and the CO2-rich phase is conveyed to a regenerator for carbon dioxide desorption. In the case of different formulations of the phase-change absorbent, e.g., different phase separating agents in the phase-change absorbent, two phase-separation scenarios generally occur: the CO2-lean phase is a heavy phase and the CO2-rich phase is a light phase; or, the CO2-lean phase is a light phase and the CO2-rich phase is a heavy phase. In the same phase-change absorbent formulation, the above two phase-separation scenarios may also occur due to the influence of the flue gas flow rate, carbon dioxide concentration in flue gas, impurities in flue gas, the absorption temperature and so on. Moreover, due to various factors, continuous switching between the two phase-separation scenarios may occur during the actual operation. However, existing carbon dioxide capture systems are typically designed for only one phase-separation scenario, and cannot accommodate various phase-separation scenarios, not to mention the switching phase-separation scenarios. For example, in a carbon dioxide capture system designed for the scenario that the CO2-lean phase is a heavy phase and the CO2-rich phase is a light phase, the light phase, namely the CO2-rich phase, is typically fixedly conveyed to the regenerator for carbon dioxide desorption, and the carbon dioxide capture system cannot convey the heavy phase, namely the CO2-rich phase, to the regenerator for carbon dioxide desorption when the phase-separation scenario changes, for example, the phase-separation scenario changes to the scenario that the CO2-lean phase is a light phase and the CO2-rich phase is a heavy phase.In view of the above, an embodiment of the present application provides a carbon dioxide capture system 100, as shown in FIG. 1, the carbon dioxide capture system 100 may include an absorption tower 101, a first carbon dioxide detection device 102, a second carbon dioxide detection device 103, a first conveying pipeline 104, a second conveying pipeline 105, a third conveying pipeline 106, a fourth conveying pipeline 107, an absorbent mixing unit 108, a heat exchange unit 109, and a regenerator 110; the absorption tower 101 has a bottom section divided into a first chamber 1011 and a second chamber 1012 by a partition assembly, an absorption liquid flows into the first chamber 1011 and then overflows from the first chamber 1011 to the second chamber 1012 via the top of the second chamber 1012, and the second chamber 1012 is configured to perform phase-separation on the inflowing absorption liquid; a shell of the absorption tower 101 corresponding to the second chamber 1012 is provided with a light phase outlet A for discharging a light phase solution and a heavy phase outlet B for discharging a heavy phase solution, and the light phase solution has a density less than that of the heavy phase solution; the first carbon dioxide detection device 102 is configured to detect parameters related to the carbon dioxide content in the light phase solution, and the second carbon dioxide detection device 103 is configured to detect parameters related to the carbon dioxide content in the heavy phase solution; the light phase outlet A communicates with an inlet of the absorbent mixing unit 108 through the first conveying pipeline 104, and the light phase outlet A communicates with a first inlet of the heat exchange unit 109 through the second conveying pipeline 105; the heavy phase outlet B communicates with the inlet of the absorbent mixing unit 108 through the third conveying pipeline 106, and the heavy phase outlet B communicates with the first inlet of the heat exchange unit 109 through the fourth conveying pipeline 107; and a first outlet of the heat exchange unit 109 communicates with an inlet of the regenerator 110, and a second inlet of the heat exchange unit 109 communicates with the bottom section of the regenerator 110; a second outlet of the heat exchange unit 109 communicates with the inlet of the absorbent mixing unit 108, and an outlet of the absorbent mixing unit 108 communicates with an absorbent inlet Z of the absorption tower 101.The absorption tower 101 may absorb carbon dioxide in a carbon dioxide-containing gas X using an absorbent. In the absorption tower 101, the absorbent flows from the top downward, the carbon dioxide-containing gas X flows from the bottom upward, and the absorbent is in countercurrent contact with the carbon dioxide-containing gas X, thereby achieving absorption of carbon dioxide. A tail gas Y after the carbon dioxide is removed is discharged from the top of the absorption tower 101, and CO₂-loaded absorption liquid may be simply referred to as an absorption liquid, that is, an absorption liquid subsequently flowing into the first chamber 1011 and the second chamber 1012 is specifically the CO₂-loaded absorption liquid.Since the bottom section of the absorption tower 101 is divided into the first chamber 1011 and the second chamber 1012, there may be a case where only one of the chambers is used to contain the absorption liquid. Thus, in order to ensure that only one chamber is used to contain the absorption liquid, the chamber can still satisfy the liquid-holding capacity requirements. In one embodiment, the absorption tower 101 includes a packing section and a bottom section, the bottom section having a diameter greater than that of the packing section; and the packing section can provide a place for gas-liquid phase contact, where a carbon dioxide absorption reaction occurs. Thus, the capacity of each chamber in the bottom section can be increased to satisfy the liquid-holding capacity requirements of a single chamber.In an embodiment of the present application, to ensure that the absorption liquid can first flow into the first chamber 1011 and then overflow from the first chamber 1011 into the second chamber 1012 via the top of the second chamber 1012, the partition assembly may include a first baffle 1013 and a second baffle 1014; the first baffle 1013 extends from a base of the bottom section of the absorption tower 101 to the packing section of the absorption tower 101 for dividing the bottom section of the absorption tower 101 into the first chamber 1011 and the second chamber 1012; the second baffle 1014 extends from the shell of the absorption tower 101 corresponding to the top of the second chamber 1012 to the top of the first chamber 1011 for covering the top of the second chamber 1012; and a flow passage for the absorption liquid is defined between the first baffle 1013 and the second baffle 1014. That is, the absorption liquid may overflow to the second chamber 1012 via the flow passage defined between the first baffle 1013 and the second baffle 1014, as indicated by an arrow in FIG. 2.In a specific implementation, the second baffle 1014 may further include an inclined portion and a vertical portion which are connected. The inclined portion has a downwardly inclined angle and extends to the top of the first chamber 1011. On one hand, the top of the second chamber 1012 can be covered, and on the other hand, the absorption liquid can be guided to the first chamber 1011, so that the absorption liquid can smoothly and rapidly flow into the first chamber 1011. The vertical portion is arranged in the first chamber 1011. On one hand, the flow passage for the absorption liquid can be defined between the vertical portion and the first baffle 1013, and on the other hand, it can be ensured that the absorption liquid first flows into the first chamber 1011 and then overflows into the second chamber 1012.In an embodiment of the present application, in the case where the absorbent is a phase-change absorbent and CO₂-loaded absorption liquid forms two immiscible phases: a CO2-lean phase and a CO2-rich phase, the second chamber 1012 may be used to perform phase-separation on the inflowing absorption liquid. In a specific implementation, a phase-separation device 1015 may be disposed in the second chamber 1012. By providing the phase-separation device 1015 in the second chamber 1012, separation of a light phase and a heavy phase in the absorption liquid can be promoted, increasing the separation efficiency. The phase-separation device 1015 may be any device capable of performing phase-separation on the absorption liquid, and the phase-separation device 1015 may perform phase-separation on the absorption liquid based on the physical properties of the absorption liquid or the chemical properties of the absorption liquid.To ensure that the heavy phase solution, rather than the light phase solution, is discharged from the heavy phase outlet B, the heavy phase outlet B can be disposed at the bottom of the second chamber 1012, for example, the heavy phase outlet B can be disposed in a lower head of the absorption tower 101.To ensure that the light phase solution, rather than the heavy phase solution, is discharged from the light phase outlet A, the light phase outlet A can be located above the highest two-phase interface (i.e., the highest position of an interface between the light phase solution and the heavy phase solution) in the second chamber 1012. The highest two-phase interface can be calculated based on physical property parameters such as the density, viscosity, surface tension, etc. of the light phase solution and the heavy phase solution, and geometry parameters of the phase-separation device 1015. The highest two-phase interface may also be regarded as a high-alarm interface of the two-phase interface.Considering that the operating conditions and the formulation for the phase-change absorbent may change, resulting in a change in the highest two-phase interface, in order to smoothly discharge the light phase solution under various operating conditions and various phase-change absorbent formulations, a plurality of light phase outlets A may be provided in practical applications, each light phase outlet A being located above the corresponding highest two-phase interface.In the case where the plurality of light phase outlets A are provided, each light phase outlet A communicates with the inlet of the absorbent mixing unit 108 via the first conveying pipeline 104, and each light phase outlet A communicates with the first inlet of the heat exchange unit 109 via the second conveying pipeline 105.In an embodiment of the present application, in order to further simplify a pipeline design and save costs, the carbon dioxide capture system 100 provided in the embodiment of the present application may further include a light phase pipeline 111 and a heavy phase pipeline 112; the light phase outlet A communicates with the inlet of the absorbent mixing unit 108 through the light phase pipeline 111 and the first conveying pipeline 104 in sequence, and the light phase outlet A communicates with the first inlet of the heat exchange unit 109 through the light phase pipeline 111 and the second conveying pipeline 105 in sequence; the heavy phase outlet B communicates with the inlet of the absorbent mixing unit 108 through the heavy phase pipeline 112 and the third conveying pipeline 106 in sequence, and the heavy phase outlet B communicates with the first inlet of the heat exchange unit 109 through the heavy phase pipeline 112 and the fourth conveying pipeline 107 in sequence.That is, after flowing out of the light phase outlet A, the light phase solution first enters the light phase pipeline 111, and then enters the first conveying pipeline 104 or the second conveying pipeline 105 after reaching a pipeline branch. Similarly, after flowing out of the heavy phase outlet B, the heavy phase solution first enters the heavy phase pipeline 112, and then enters the third conveying pipeline 106 or the fourth conveying pipeline 107 after reaching a pipeline branch.In order to simplify the control of the system, a light-phase three-way valve 113 may be disposed at an outlet position of the light phase pipeline 111, i.e., the pipeline branch, for connecting the light phase pipeline 111, the first conveying pipeline 104 and the second conveying pipeline 105. Similarly, a heavy-phase three-way valve 114 may be disposed at an outlet position of the heavy phase pipeline 112, i.e., the pipeline branch, for connecting the heavy phase pipeline 112, the third conveying pipeline 106 and the fourth conveying pipeline 107.Further, a light phase pump 115 may also be disposed on the light phase pipeline 111 and a heavy phase pump 116 may also be disposed on the heavy phase pipeline 112 in order to draw out the light phase solution from the light phase outlet A and the heavy phase solution from the heavy phase outlet B.In an embodiment of the present application, the first carbon dioxide detection device 102 may be configured to detect the parameters related to the carbon dioxide content in the light phase solution in real time, and the second carbon dioxide detection device 103 may be configured to detect the parameters related to the carbon dioxide content in the heavy phase solution in real time. The parameters related to the carbon dioxide content may include parameters such as a pH, conductivity, chromatography, infrared spectroscopy, and Raman spectroscopy that can reflect the carbon dioxide content (the content may be a concentration or the mass content). That is, after obtaining such parameters, the carbon dioxide content can be obtained directly or by related calculations. It can be appreciated that the first carbon dioxide detection device 102 and the second carbon dioxide detection device 103 may be instruments corresponding to the parameters described above.In practical applications, the first carbon dioxide detection device 102 may detect the parameters related to the carbon dioxide content in the light phase solution after the light phase solution is discharged from the second chamber 1012 or before the light phase solution is discharged from the second chamber 1012. In the case where the first carbon dioxide detection device 102 detects the light phase solution discharged from the second chamber 1012, a detection port may be formed in the light phase pipeline 111, and the first carbon dioxide detection device 102 may be connected to the detection port to detect the light phase solution through the detection port. In the case where the first carbon dioxide detection device 102 detects the light phase solution in the second chamber 1012, a light phase detection port may be formed in the shell of the absorption tower 101 corresponding to the second chamber 1012, and the first carbon dioxide detection device 102 may be connected to the light phase detection port to detect the light phase solution through the light phase detection port. In order to ensure that a detection object of the first carbon dioxide detection device 102 is the light phase solution rather than the heavy phase solution, the light phase detection port formed in the shell of the absorption tower 101 may be located above the highest two-phase interface.Similarly, the second carbon dioxide detection device 103 may detect the parameters related to the carbon dioxide content in the heavy phase solution after the heavy phase solution is discharged from the second chamber 1012 or before the heavy phase solution is discharged from the second chamber 1012. In the case where the second carbon dioxide detection device 103 detects the heavy phase solution discharged from the second chamber 1012, a detection port may be formed in the heavy phase pipeline 112, and the second carbon dioxide detection device 103 may be connected to the detection port to detect the heavy phase solution through the detection port. In the case where the second carbon dioxide detection device 103 detects the heavy phase solution in the second chamber 1012, a heavy phase detection port may be formed in the shell of the absorption tower 101 corresponding to the second chamber 1012, and the second carbon dioxide detection device 103 may be connected to the heavy phase detection port to detect the heavy phase solution through the heavy phase detection port. In order to ensure that a detection object of the second carbon dioxide detection device 103 is the heavy phase solution rather than the light phase solution, the heavy phase detection port formed in the shell of the absorption tower 101 may be located below the lowest two-phase interface (i.e., the lowest position of the interface between the light phase solution and the heavy phase solution). The lowest two-phase interface can be calculated based on physical property parameters such as the density, viscosity, surface tension, etc. of the light phase solution and the heavy phase solution, and geometry parameters of the phase-separation device 1015. The lowest two-phase interface may also be regarded as a low-alarm interface of the two-phase interface.In an embodiment of the present application, the absorbent mixing unit 108 may be used to collect and mix the CO2-lean phase (a light phase or a heavy phase discharged from the absorption tower 101) and a lean liquid after desorption to obtain an absorbent, and the absorbent is then further conveyed to the absorption tower 101 to continue to participate in a reaction of absorbing carbon dioxide. The heat exchange unit 109 may be used for collecting the CO2-rich phase (the light phase or the heavy phase discharged from the absorption tower 101) and for drawing out a high-temperature lean liquid after carbon dioxide desorption from the bottom section of the regenerator 110, and the CO2-rich phase and the high-temperature lean liquid are subjected to heat exchange in the heat exchange unit 109. The CO2-rich phase after heat exchange is further fed into the regenerator 110 for carbon dioxide desorption, and the lean liquid after heat exchange is further fed into the absorbent mixing unit 108. The regenerator 110 is a column including a plurality of internal components such as packing and trays, and heating is performed by a reboiler 1101 to perform carbon dioxide desorption, and carbon dioxide desorbed at the top of the regenerator 110 continues to enter a subsequent stage.Then, based on the functions of the absorbent mixing unit 108 and the heat exchange unit 109, it can be understood that:when a phase-separation result in the second chamber 1012 is that the CO2-lean phase is a light phase and the CO2-rich phase is a heavy phase (i.e., the light phase solution discharged from the light phase outlet A is the CO2-lean phase and the heavy phase solution discharged from the heavy phase outlet B is the CO2-rich phase), the light phase solution discharged from the light phase outlet A may be conveyed to the absorbent mixing unit 108 via the light phase pipeline 111 and the first conveying pipeline 104. Meanwhile, the heavy phase solution discharged from the heavy phase outlet B may be conveyed to the heat exchange unit 109 through the heavy phase pipeline 112 and the fourth conveying pipeline 107. In the heat exchange unit 109, the heavy phase solution exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator 110. The heavy phase solution after heat exchange is further fed into the regenerator 110 for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further conveyed to the absorbent mixing unit 108. The absorbent mixing unit 108 mixes the CO2-lean phase collected from the light phase outlet A with the lean liquid collected from the heat exchange unit 109, and the obtained mixture is then conveyed to the absorption tower 101 to continue to participate in the reaction of absorbing carbon dioxide.When the phase-separation result in the second chamber 1012 is that the CO2-lean phase is a heavy phase and the CO2-rich phase is a light phase (i.e., the light phase solution discharged from the light phase outlet A is the CO2-rich phase and the heavy phase solution discharged from the heavy phase outlet B is the CO2-lean phase), the light phase solution discharged from the light phase outlet A can be conveyed to the heat exchange unit 109 through the light phase pipeline 111 and the second conveying pipeline 105. In the heat exchange unit 109, the light phase solution exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator 110. The light phase solution after heat exchange is further fed into the regenerator 110 for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further conveyed to the absorbent mixing unit 108. Meanwhile, the heavy phase solution discharged from the heavy phase outlet B may be conveyed to the absorbent mixing unit 108 through the heavy phase pipeline 112 and the third conveying pipeline 106. The absorbent mixing unit 108 mixes the CO2-lean phase collected from the heavy phase outlet B with the lean liquid collected from the heat exchange unit 109, and the obtained mixture is then conveyed to the absorption tower 101 to continue to participate in the reaction of absorbing carbon dioxide.In a specific implementation, to further improve the absorption effect of an absorbent conveyed from the heat exchange unit 109 to the absorption tower 101, the carbon dioxide capture system 100 provided in the embodiments of the present application may further include a lean liquid cooler 117 disposed on a pipeline connecting the outlet of the heat exchange unit 109 to the absorbent inlet Z of the absorption tower 101. To facilitate subsequent control, the pipeline connecting the outlet of the heat exchange unit 109 to the absorbent inlet Z of the absorption tower 101 may also be provided with an absorbent flow meter 145.In practical applications, in order to control the actual two-phase interface in the second chamber 1012 and the flow rate of the solution conveyed to the heat exchange unit 109, so as to enable long-term stable operation of the system, in an embodiment, the shell of the absorption tower 101 corresponding to the second chamber 1012 is further provided with an interface detection device 1016, and the second conveying pipeline 105 is provided with a first flow meter 118 and a first flow regulating valve 119; the fourth conveying pipeline 107 is provided with a second flow meter 120 and a second flow regulating valve 121; and the interface detection device 1016 is configured to detect the position of a two-phase interface between the light phase solution and the heavy phase solution in the second chamber 1012.In addition to detecting the position of the two-phase interface between the light phase solution and the heavy phase solution in the second chamber 1012, the interface detection device 1016 may also detect the liquid level of the solution in the second chamber 1012, and the interface detection device 1016 may specifically be an interface meter. In a specific implementation, the shell of the absorption tower 101 corresponding to the second chamber 1012 may be provided with an upper interface meter port C and a lower interface meter port D, and the upper interface meter port C and the lower interface meter port D are connected to the interface meter. In actual arrangement, the upper interface meter port C may be located above the highest two-phase interface and the lower interface meter port D may be located below the lowest two-phase interface. Also, the shell of the absorption tower 101 corresponding to the second chamber 1012 may also be provided with a viewing window 1017 for assisting in observing the phase-separation scenario in the second chamber 1012.The first flow meter 118 can be used to detect the flow rate of the light phase solution in the second conveying pipeline 105 in real time, and the first flow regulating valve 119 can be used to regulate the flow rate of the light phase solution in the second conveying pipeline 105. The second flow meter 120 can be used to detect the flow rate of the heavy phase solution in the fourth conveying pipeline 107 in real time, and the second flow regulating valve 121 can be used to regulate the flow rate of the heavy phase solution in the fourth conveying pipeline 107.Further, in order to achieve automatic control of the two-phase interface and automatic control of the flow rate of the solution conveyed to the heat exchange unit 109, an interface controller 1018 is also disposed on the shell of the absorption tower 101 corresponding to the second chamber 1012, a light-phase flow controller 122 is also disposed on the second conveying pipeline 105, and a heavy-phase flow controller 123 is also disposed on the fourth conveying pipeline 107.It will be appreciated that the carbon dioxide capture system 100 provided in the above embodiment of the present application is applicable regardless whether the CO2-lean phase is a heavy phase and the CO2-rich phase is a light phase, or the CO2-lean phase is a light phase and the CO2-rich phase is a heavy phase. That is, the carbon dioxide capture system 100 provided in the above embodiment of the present application can accommodate various phase-separation scenarios and has a high flexibility. When the phase-separation scenario changes, there is no need to replace equipment or make additional designs, so as to greatly reduce the equipment investment cost of the carbon dioxide capture system.Considering that the carbon dioxide capture technology based on the single-phase absorbent is also one of the more commonly used carbon dioxide capture technologies at present, the principle of this carbon dioxide capture technology is that the single-phase absorbent absorbs carbon dioxide to obtain a single-phase absorption liquid (which may also be referred to as a rich liquid), and the single-phase absorption liquid is conveyed to the regenerator for carbon dioxide desorption. It can be seen that the principle of the carbon dioxide capture technology based on the single-phase absorbent and the principle of the carbon dioxide capture technology based on the phase-change absorbent have a large difference, the former does not undergo phase-separation, while the latter does undergo phase-separation. Based on this difference, existing carbon dioxide capture systems are designed for either the carbon dioxide capture technology based on the single-phase absorbent or the carbon dioxide capture technology based on the phase-change absorbent, and cannot accommodate the two carbon dioxide capture technologies.To enable the carbon dioxide capture system 100 provided in the embodiments of the present application to further accommodate the carbon dioxide capture technology based on the single-phase absorbent, that is, the single-phase absorbent can be used as an absorbent of the absorption tower 101, and in an embodiment, a first outlet E is formed at the bottom of the first chamber 1011, and the carbon dioxide capture system 100 further includes a fifth conveying pipeline 124; the first outlet E of the first chamber 1011 communicates with the first inlet of the heat exchange unit 109 through the fifth conveying pipeline 124.Thus, when the single-phase absorbent is used as the absorbent of the absorption tower 101, a CO₂-loaded single-phase absorption liquid in the first chamber 1011 can be directly conveyed to the heat exchange unit 109 through the fifth conveying pipeline 124. In the heat exchange unit 109, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator 110. The single-phase absorption liquid after heat exchange is further fed into the regenerator 110 for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further conveyed to the absorbent mixing unit 108. It can be appreciated that when the single-phase absorbent is used as the absorbent of the absorption tower 101, the single-phase absorption liquid formed after absorbing carbon dioxide remains in the first chamber 1011 and does not overflow to the second chamber 1012. To smoothly draw out the single-phase absorption liquid from the first outlet E, a single-phase pump 125 may also be disposed on the fifth conveying pipeline 124.In practical applications, in order to control the liquid level in the first chamber 1011 and the flow rate of the solution conveyed to the heat exchange unit 109, so as to enable long-term stable operation of the system, a shell of the absorption tower corresponding to the first chamber 1011 may be provided with a liquid level detection device 1019, and the fifth conveying pipeline 124 may be provided with a third flow meter 126 and a third flow regulating valve 127.The liquid level detection device 1019 may be used to detect the liquid level of the solution in the first chamber 1011 and may specifically be a liquid level meter. In a specific implementation, the shell of the absorption tower 101 corresponding to the first chamber 1011 may be provided with an upper liquid level meter port F and a lower liquid level meter port G which are connected to the liquid level meter. In actual arrangement, the upper liquid level meter port F may be located above the highest liquid level and the lower liquid level meter port G may be located below the lowest liquid level. The highest liquid level may be set according to the height of the first baffle 1013, for example, the highest liquid level may be 300 mm to 1500 mm above the highest point of the first baffle 1013. The lowest liquid level may be 300 mm to 500 mm above the bottom section of the absorption tower 101. The highest liquid level and the lowest liquid level may also be regarded as alarm levels.The third flow meter 126 can be used to detect the flow rate of the single-phase absorption liquid in the fifth conveying pipeline 124 in real time, and the third flow regulating valve 127 can be used to regulate the flow rate of the single-phase absorption liquid in the fifth conveying pipeline 124.Further, in order to achieve automatic control of the liquid level of the solution in the first chamber 1011, a liquid level controller 128 may be further disposed on the shell of the absorption tower 101 corresponding to the first chamber 1011, and a single-phase flow controller 129 may be further disposed on the fifth conveying pipeline 124.Considering that under the same phase-change absorbent formulation, due to the influence of the flue gas flow rate, carbon dioxide concentration in flue gas, impurities in flue gas, the absorption temperature and so on, the phase-separation scenario that the CO2-lean phase is a heavy phase and the CO2-rich phase is a light phase or the phase-separation scenario that the CO2-lean phase is a light phase and the CO2-rich phase is a heavy phase may occur. In addition, no phase-separation may also occur, i.e., after absorbing carbon dioxide, the phase-change absorbent remains single-phase, thereby obtaining a single-phase absorption liquid (which may also be referred to as a rich liquid).In order to enable the carbon dioxide capture system 100 provided in the embodiments of the present application to further accommodate the non-phase-separation scenario described above, in an embodiment, the bottom of the first chamber 1011 is further provided with a second outlet H, the bottom of the second chamber 1012 is further provided with a third outlet I, and the carbon dioxide capture system 100 further includes a sixth conveying pipeline 130; the second outlet H of the first chamber 1011 communicates with the third outlet I of the second chamber 1012 through the sixth conveying pipeline 130. In practical applications, the sixth conveying pipeline 130 may be further provided with an on-off valve 131.Thus, when the phase-change absorbent is used as the absorbent of the absorption tower 101, and the phase-separation result in the second chamber 1012 is that no phase-separation occurs and the absorbent remains single phase, the on-off valve 131 and the fifth conveying pipeline 124 may be opened, and the solution in the bottom section of the absorption tower 101 (i.e., the solution in the first chamber 1011 and the second chamber 1012), i.e., the single-phase absorption liquid, is withdrawn from the first outlet E, and then conveyed to the heat exchange unit 109 through the fifth conveying pipeline 124. In the heat exchange unit 109, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator 110. The single-phase absorption liquid after heat exchange is further fed into the regenerator 110 for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further conveyed to the absorbent mixing unit 108.In the case where the single-phase absorbent is used as the absorbent of the absorption tower 101 and the phase-change absorbent remains single phase after absorbing carbon dioxide, all the absorption liquid is conveyed to the heat exchange unit 109, and the heat exchange capacity requirement is large. Thus, in an embodiment of the present application, the heat exchange unit 109 may include a first heat exchanger 1091 and a second heat exchanger 1092; the light phase outlet A communicates with a first inlet of the first heat exchanger 1091 through the second conveying pipeline 105, and the heavy phase outlet B communicates with the first inlet of the first heat exchanger 1091 through the fourth conveying pipeline 107; the first outlet E of the first chamber 1011 communicates with the first inlet of the first heat exchanger 1091 and a first inlet of the second heat exchanger 1092 through the fifth conveying pipeline 124; both a first outlet of the first heat exchanger 1091 and a first outlet of the second heat exchanger 1092 communicate with the inlet of the regenerator 110, and both a second inlet of the first heat exchanger 1091 and a second inlet of the second heat exchanger 1092 communicate with the bottom section of the regenerator 110; and both a second outlet of the first heat exchanger 1091 and a second outlet of the second heat exchanger 1092 communicate with the inlet of the absorbent mixing unit 108.When phase-separation is performed to obtain a light phase solution and a heavy phase solution, and the CO2-rich phase is conveyed to the heat exchange unit 109, specifically, the CO2-rich phase may be conveyed to the first heat exchanger 1091. In the first heat exchanger 1091, the CO2-rich phase exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator 110. The CO2-rich phase after heat exchange is further fed into the regenerator 110 for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further conveyed to the absorbent mixing unit 108.When the single-phase absorption liquid is conveyed to the heat exchange unit 109, specifically, the single-phase absorption liquid may be diverted and conveyed to the first heat exchanger 1091 and the second heat exchanger 1092. In the first heat exchanger 1091, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator 110. The single-phase absorption liquid after heat exchange is further fed into the regenerator 110 for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further conveyed to the absorbent mixing unit 108. The second heat exchanger 1092 operates in the same manner, which will not be described in detail here.In practical applications, in order to simplify control of the system, the carbon dioxide capture system 100 provided in the embodiments of the present application may further include a rich liquid main pipeline 132 and a rich liquid three-way valve 133, and an outlet of the second conveying pipeline 105, an outlet of the fourth conveying pipeline 107 and an outlet of the fifth conveying pipeline 124 all communicate with an inlet of the rich liquid main pipeline 132; and the rich liquid three-way valve 133 is disposed at an outlet position of the rich liquid main pipeline 132, i.e., a pipeline branch. The other two ports of the rich liquid three-way valve 133 are respectively connected to inlets of two branch pipelines, which are an inlet of a first rich liquid branch pipeline 134 and an inlet of a second rich liquid branch pipeline 135, respectively, an outlet of the first rich liquid branch pipeline 134 communicates with the first inlet of the first heat exchanger 1091, and an outlet of the second rich liquid branch pipeline 135 communicates with the first inlet of the second heat exchanger 1092.It can be appreciated that when phase-separation is performed to obtain a light phase solution and a heavy phase solution, and the CO2-rich phase is conveyed to the first heat exchanger 1091, the CO2-rich phase may be conveyed to the first heat exchanger 1091 via the rich liquid main pipeline 132 and the first rich liquid branch pipeline 134. When the single-phase absorption liquid is diverted and conveyed to the first heat exchanger 1091 and the second heat exchanger 1092, the single-phase absorption liquid can first enter the rich liquid main pipeline 132, then be diverted into the first rich liquid branch pipeline 134 and the second rich liquid branch pipeline 135, and then be conveyed to the first heat exchanger 1091 via the first rich liquid branch pipeline 134 and to the second heat exchanger 1092 via the second rich liquid branch pipeline 135. The single-phase absorption liquid having an increased temperature discharged from the first heat exchanger 1091 and the second heat exchanger 1092 is converged and further fed into the regenerator 110 for carbon dioxide desorption.In the case where the heat exchange unit 109 includes the first heat exchanger 1091 and the second heat exchanger 1092, correspondingly, the carbon dioxide capture system 100 provided in the embodiments of the present application may further include a first lean liquid main pipeline 136, a first lean liquid three-way valve 137, a first lean liquid branch pipeline 138 and a second lean liquid branch pipeline 139. The bottom section of the regenerator 110 communicates with an inlet of the first lean liquid main pipeline 136, and the first lean liquid three-way valve 137 is disposed at an outlet position of the first lean liquid main pipeline 136, i.e., a pipeline branch. The other two ports of the first lean liquid three-way valve 137 are respectively connected to an inlet of the first lean liquid branch pipeline 138 and an inlet of the second lean liquid branch pipeline 139, an outlet of the first lean liquid branch pipeline 138 communicates with the second inlet of the first heat exchanger 1091, and an outlet of the second lean liquid branch pipeline 139 communicates with the second inlet of the second heat exchanger 1092. Further, a lean liquid pump 140 may also be disposed on the first lean liquid main pipeline 136.Since all the absorption liquid is conveyed to the heat exchange unit 109 in the case where the single-phase absorbent is used as the absorbent of the absorption tower 101 and the phase-change absorbent remains single phase after absorbing carbon dioxide, the flow rate in the system is large. In order to match the flow rate, in one embodiment, the absorbent mixing unit 108 includes a first mixer 1081 and a second mixer 1082; the light phase outlet A communicates with an inlet of the first mixer 1081 through the first conveying pipeline 104, and the heavy phase outlet B communicates with an inlet of the second mixer 1082 through the third conveying pipeline 106; the second outlet of the first heat exchanger 1091 communicates with both the inlet of the first mixer 1081 and the inlet of the second mixer 1082, and the second outlet of the second heat exchanger 1092 communicates with both the inlet of the first mixer 1081 and the inlet of the second mixer 1082.The first mixer 1081 may serve as a light phase mixer and the second mixer 1082 may serve as a heavy phase mixer.That is, when the light phase solution discharged from the light phase outlet A is a CO2-lean phase and the heavy phase solution discharged from the heavy phase outlet B is a CO2-rich phase, the light phase solution can be conveyed to the first mixer 1081. When the light phase solution discharged from the light phase outlet A is a CO2-rich phase and the heavy phase solution discharged from the heavy phase outlet B is a CO2-lean phase, the heavy phase solution can be conveyed to the second mixer 1082.In practical applications, to simplify the control of the system, the carbon dioxide capture system 100 in the embodiments of the present application may further include a second lean liquid main pipeline 141, a second lean liquid three-way valve 142, a third lean liquid branch pipeline 143 and a fourth lean liquid branch pipeline 144. Both the second outlet of the first heat exchanger 1091 and the second outlet of the second heat exchanger 1092 communicate with an inlet of the second lean liquid main pipeline 141, the second lean liquid three-way valve 142 is arranged at an outlet position of the second lean liquid main pipeline 141, i.e., a pipeline branch. The other two ports of the second lean liquid main pipeline 141 are respectively connected to an inlet of the third lean liquid branch pipeline 143 and an inlet of the fourth lean liquid branch pipeline 144, an outlet of the third lean liquid branch pipeline 143 communicates with the inlet of the first mixer 1081, and an outlet of the fourth lean liquid branch pipeline 144 communicates with the inlet of the second mixer 1082.That is, the lean liquid discharged from the first heat exchanger 1091 and the second heat exchanger 1092 is first converged in the second lean liquid main pipeline 141, and then conveyed to the first mixer 1081 through the third lean liquid branch pipeline 143, to the second mixer 1082 through the fourth lean liquid branch pipeline 144, or to the first mixer 1081 and the second mixer 1082 through the third lean liquid branch pipeline 143 and the fourth lean liquid branch pipeline 144, respectively. Specifically, when the light phase solution is conveyed to the first mixer 1081, the lean liquid discharged from the first heat exchanger 1091 and the second heat exchanger 1092 may first be converged in the second lean liquid main pipeline 141 and then conveyed to the first mixer 1081 through the third lean liquid branch pipeline 143. When the heavy phase solution is conveyed to the second mixer 1082, the lean liquid discharged from the first heat exchanger 1091 and the second heat exchanger 1092 may first be converged in the second lean liquid main pipeline 141 and then conveyed to the second mixer 1082 through the fourth lean liquid branch pipeline 144. When the single-phase absorption liquid is conveyed to the first heat exchanger 1091 and the second heat exchanger 1092, the lean liquid discharged from the first heat exchanger 1091 and the second heat exchanger 1092 may first be converged in the second lean liquid main pipeline 141 and then conveyed to the first mixer 1081 and the second mixer 1082 through the third lean liquid branch pipeline 143 and the fourth lean liquid branch pipeline 144, respectively.It can be understood that the carbon dioxide capture system 100 provided in the above embodiment of the present application is applicable not only to two phase-separation scenarios generated by using the phase-change absorbent, i.e., the CO2-lean phase being the heavy phase, the CO2-rich phase being the light phase and the CO2-lean phase being the light phase and the CO2-rich phase being the heavy phase, but also to the non-phase-separation scenario generated by using the phase-change absorbent, and is further applicable to the scenario where the single-phase absorbent is used. It can be seen that the carbon dioxide capture system 100 provided in the above embodiment of the present application substantially accommodates both the single-phase scenario and various phase-separation scenarios and has high versatility.In a specific implementation, the carbon dioxide capture system 100 provided in the above embodiment of the present application may further be combined with a flue gas treatment device 201 disclosed by the applicant in CN115970460B, a solvent recovery unit 202, an interstage cooling unit 203 and a regeneration gas condensing unit 204 which are disclosed by the applicant in CN116531918B, and an amine liquid purification device 205 disclosed by the applicant in CN116870663A, as shown in FIG. 3. For the arrangement positions of the flue gas treatment device 201, the solvent recovery unit 202, the interstage cooling unit 203, the regeneration gas condensing unit 204 and the amine liquid purification device 205, reference can be made to the relevant contents of CN115970460B, CN116531918B and CN116870663A, respectively, which will not be described in detail here.Based on the carbon dioxide capture system provided in the above embodiment of the present application, an embodiment of the present application further provides a control method for the carbon dioxide capture system, and the control method can be understood as a control method corresponding to a carbon dioxide capture system excluding a fifth conveying pipeline and a sixth conveying pipeline. The control method may include Steps (1) and (2), specifically as follows:Step (1), in response to the carbon dioxide content in a light phase solution being less than that in a heavy phase solution, a first conveying pipeline is opened, a second conveying pipeline is closed, and the light phase solution is controlled to be conveyed to an absorbent mixing unit via the first conveying pipeline; and a third conveying pipeline is closed, a fourth conveying pipeline is opened, and the heavy phase solution is controlled to be conveyed to a heat exchange unit via the fourth conveying pipeline.In a specific implementation, a mode selection controller for controlling the carbon dioxide capture system may be further provided in order to realize automatic control, and all signals may be transmitted to the mode selection controller, and control instructions are issued by the mode selection controller. Parameters related to the carbon dioxide content which are detected by a first carbon dioxide detection device and a second carbon dioxide detection device may be transmitted to the mode selection controller, and a difference between the carbon dioxide content in the light phase solution and the carbon dioxide content in the heavy phase solution is calculated by the mode selection controller, and mode selection is performed and corresponding control is implemented according to the difference.When the carbon dioxide content in the light phase solution is less than that in the heavy phase solution, it indicates that a CO2-lean phase is discharged from a light phase outlet and a CO2-rich phase is discharged from a heavy phase outlet. At this time, the mode selection controller automatically recognizes the system as a mode 1 and triggers the following control process:the first conveying pipeline is opened, the second conveying pipeline is closed, and the light phase solution is controlled to be conveyed to the absorbent mixing unit via the first conveying pipeline; and the third conveying pipeline is closed, the fourth conveying pipeline is opened, and the heavy phase solution is controlled to be conveyed to the heat exchange unit via the fourth conveying pipeline.In the heat exchange unit, the CO2-rich phase exchanges heat with a high-temperature lean liquid withdrawn from the bottom section of the regenerator. The CO2-rich phase after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the absorbent mixing unit. In the absorbent mixing unit, the CO2-lean phase and the lean liquid are mixed to obtain an absorbent, which is further conveyed to an absorption tower to continue to participate in a reaction of absorbing carbon dioxide.In such an embodiment, the heat exchange unit may include only one heat exchanger and the absorbent mixing unit may include only one mixer.In practical applications, since a change in the circulating flow rate of the CO2-rich phase has a greater influence on a two-phase interface, the position of a two-phase interface in a second chamber can be controlled based on an interface controller and a heavy-phase flow controller to maintain stability of the two-phase interface. For example, a normal two-phase interface position can be set, and when the measured two-phase interface position is greater than the normal two-phase interface position, the opening of a second flow regulating valve can be controlled to increase; and when the measured two-phase interface position is less than the normal two-phase interface position, the opening of the second flow regulating valve may be controlled to decrease. The normal two-phase interface position can be determined according to an optimal operating distribution ratio of a light phase solution to a heavy phase solution in a phase-change absorbent employed.Further, the flow rate of the light phase solution can also be controlled based on a light-phase flow controller such that flow rate of light phase solution = flow rate of absorbent-flow rate of heavy phase solution. Thus, it can be ensured that the carbon dioxide capture system can be operated stably for a long period of time.Step (2), in response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, the first conveying pipeline is closed, the second conveying pipeline is opened, and the light phase solution is controlled to be conveyed to the heat exchange unit via the second conveying pipeline; and the third conveying pipeline is opened, the fourth conveying pipeline is closed, and the heavy phase solution is controlled to be conveyed to the absorbent mixing unit via the third conveying pipeline.When the carbon dioxide content in the light phase solution is greater than that in the heavy phase solution, it indicates that the CO2-rich phase is discharged from the light phase outlet and the CO2-lean phase is discharged from the heavy phase outlet. At this time, the mode selection controller automatically recognizes the system as a mode 2 and triggers the following control process:the first conveying pipeline is closed, the second conveying pipeline is opened, and the light phase solution is controlled to be conveyed to the heat exchange unit via the second conveying pipeline; and the third conveying pipeline is opened, the fourth conveying pipeline is closed, and the heavy phase solution is controlled to be conveyed to the absorbent mixing unit via the third conveying pipeline.Similarly, in the heat exchange unit, the CO2-rich phase exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The CO2-rich phase after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the absorbent mixing unit. In the absorbent mixing unit, the CO2-lean phase and the lean liquid are mixed to obtain an absorbent, which is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.In such an embodiment, the heat exchange unit may include only one heat exchanger and the absorbent mixing unit may include only one mixer.In practical applications, since the change in the circulating flow rate of the CO2-rich phase has a greater influence on the two-phase interface, the position of the two-phase interface in the second chamber can be controlled based on the interface controller and the light-phase flow controller to maintain stability of the two-phase interface. For example, the normal two-phase interface position can be set, and when the measured two-phase interface position is greater than the normal two-phase interface position, the opening of a first flow regulating valve can be controlled to decrease; and when the measured two-phase interface position is less than the normal two-phase interface position, the opening of the first flow regulating valve may be controlled to increase. The normal two-phase interface position can be determined according to the optimal operating distribution ratio of the light phase solution to the heavy phase solution in the phase-change absorbent employed.Further, the flow rate of the heavy phase solution can also be controlled based on the heavy-phase flow controller such that flow rate of heavy phase solution = flow rate of absorbent-flow rate of light phase solution. Thus, it can be ensured that the carbon dioxide capture system can be operated stably for a long period of time.It can be understood that based on the control method for the carbon dioxide capture system provided in the above embodiment of the present application, the carbon dioxide capture system can be made applicable to two phase-separation scenarios generated by the phase-change absorbent: the CO2-lean phase being a heavy phase and the CO2-rich phase being a light phase and the CO2-lean phase being a light phase and the CO2-rich phase being a heavy phase. Also, automatic control can be realized, improving control efficiency and reliability and safety of the system.Based on the carbon dioxide capture system provided in the above embodiment of the present application, another embodiment of the present application also provides a control method for the carbon dioxide capture system, and the control method can be understood as a control method corresponding to a carbon dioxide capture system including a fifth conveying pipeline and excluding a sixth conveying pipeline. The control method may include Steps (1), (2) and (3), specifically as follows:Step (1), in response to the carbon dioxide content in a light phase solution being less than that in a heavy phase solution, a first conveying pipeline is opened, a second conveying pipeline is closed, and the light phase solution is controlled to be conveyed to an absorbent mixing unit via the first conveying pipeline; and a third conveying pipeline is closed, a fourth conveying pipeline is opened, and the heavy phase solution is controlled to be conveyed to a heat exchange unit via the fourth conveying pipeline. During this control process, the fifth conveying pipeline is kept closed.This step (1) corresponds to a mode 1, and a specific control process can refer to the foregoing contents, which will not be described in detail here.In the case where the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer, controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline specifically includes controlling the light phase solution to be conveyed to the first mixer via the first conveying pipeline; and controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline specifically includes controlling the heavy phase solution to be conveyed to the first heat exchanger via the fourth conveying pipeline.In the first heat exchanger, a CO2-rich phase exchanges heat with a high-temperature lean liquid withdrawn from the bottom section of the regenerator. The CO2-rich phase after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the first mixer. In the first mixer, a CO2-lean phase and the lean liquid are mixed to obtain an absorbent, which is further conveyed to an absorption tower to continue to participate in a reaction of absorbing carbon dioxide.At this time, the control logic for the mode 1 may be as shown in FIG. 4.In practical applications, since a change in the circulating flow rate of the CO2-rich phase has a greater influence on a two-phase interface, the position of a two-phase interface in a second chamber can be controlled based on an interface controller and a heavy-phase flow controller, and the flow rate of the light phase solution can be controlled based on a light-phase flow controller, and a specific control process can refer to the foregoing contents, which will not be described in detail here.Step (2), in response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, the first conveying pipeline is closed, the second conveying pipeline is opened, and the light phase solution is controlled to be conveyed to the heat exchange unit via the second conveying pipeline; and the third conveying pipeline is opened, the fourth conveying pipeline is closed, and the heavy phase solution is controlled to be conveyed to the absorbent mixing unit via the third conveying pipeline. During this control process, the fifth conveying pipeline is kept closed.This step (2) corresponds to a mode 2, and a specific control process can refer to the foregoing contents, which will not be described in detail here.In the case where the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer, controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline specifically includes controlling the light phase solution to be conveyed to the first heat exchanger via the second conveying pipeline; and controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline specifically includes controlling the heavy phase solution to be conveyed to the second mixer via the third conveying pipeline.In the first heat exchanger, the CO2-rich phase exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The CO2-rich phase after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the second mixer. In the second mixer, the CO2-lean phase and the lean liquid are mixed to obtain an absorbent, which is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.At this time, the control logic for the mode 2 may be as shown in FIG. 5.In practical applications, since the change in the circulating flow rate of the CO2-rich phase has a greater influence on the two-phase interface, the position of the two-phase interface in the second chamber can be controlled based on the interface controller and the light-phase flow controller, and the flow rate of the heavy phase solution can be controlled based on the heavy-phase flow controller, and a specific control process can refer to the foregoing contents, which will not be described in detail here.Step (3), in response to an absorbent being a single-phase absorbent, the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline are closed, the fifth conveying pipeline is opened, and the solution in a first chamber is controlled to be conveyed to the heat exchange unit.When the absorbent is the single-phase absorbent, a mode selection controller selects a mode 3 (a trigger signal for the mode 3 may be that the two-phase interface position in the second chamber is equal to the liquid level and equal to zero) and triggers the following control process:the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline are closed, the fifth conveying pipeline is opened, and the solution (i.e., a single-phase absorption liquid) in the first chamber is controlled to be conveyed to the heat exchange unit.In the heat exchange unit, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the absorbent mixing unit. The lean liquid obtained in the absorbent mixing unit is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.In the case where the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer, controlling the solution in the first chamber to be conveyed to the heat exchange unit specifically includes controlling the solution in the first chamber to be conveyed to the first heat exchanger and the second heat exchanger.In the first heat exchanger, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the first mixer and the second mixer. At the same time, in the second heat exchanger, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the first mixer and the second mixer. The lean liquid obtained in the first mixer and the second mixer is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.At this time, the control logic for the mode 3 may be as shown in FIG. 6.In practical applications, the liquid level in the first chamber can also be controlled based on a liquid level controller and a single-phase flow controller to maintain stability of the liquid level. For example, a normal liquid level can be set, and when the measured liquid level is greater than the normal liquid level, the opening of a third flow regulating valve can be controlled to increase; and when the measured liquid level is less than the normal liquid level, the opening of the third flow regulating valve may be controlled to decrease. The normal liquid level can be determined based on the total flow rate of the absorption liquid and the residence time of the absorption liquid in the absorption tower.It can be understood that based on the control method for the carbon dioxide capture system provided in the above embodiment of the present application, the carbon dioxide capture system can be made applicable to two phase-separation scenarios generated by a phase-change absorbent: the CO2-lean phase being a heavy phase and the CO2-rich phase being a light phase and the CO2-lean phase being a light phase and the CO2-rich phase being a heavy phase, and to the scenario where the single-phase absorbent is used as an absorbent of the absorption tower. Also, automatic control can be realized, improving control efficiency and reliability and safety of the system.Based on the carbon dioxide capture system provided in the above embodiment of the present application, another embodiment of the present application provides a control method for the carbon dioxide capture system, and the control method can be understood as a control method corresponding to a carbon dioxide capture system including a fifth conveying pipeline and a sixth conveying pipeline. The control method may include Steps (1), (2), (3) and (4), specifically as follows:Step (1), in response to the carbon dioxide content in a light phase solution being less than that in a heavy phase solution, a first conveying pipeline is opened, a second conveying pipeline is closed, and the light phase solution is controlled to be conveyed to an absorbent mixing unit via the first conveying pipeline; and a third conveying pipeline is closed, a fourth conveying pipeline is opened, and the heavy phase solution is controlled to be conveyed to a heat exchange unit via the fourth conveying pipeline. During this control process, the fifth conveying pipeline and the sixth conveying pipeline are kept closed.This step (1) corresponds to a mode 1, and a specific control process can refer to the foregoing contents, which will not be described in detail here.In the case where the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer, controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline specifically includes controlling the light phase solution to be conveyed to the first mixer via the first conveying pipeline; and controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline specifically includes controlling the heavy phase solution to be conveyed to the first heat exchanger via the fourth conveying pipeline.In the first heat exchanger, a CO2-rich phase exchanges heat with a high-temperature lean liquid withdrawn from the bottom section of the regenerator. The CO2-rich phase after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the first mixer. In the first mixer, a CO2-lean phase and the lean liquid are mixed to obtain an absorbent, which is further conveyed to an absorption tower to continue to participate in a reaction of absorbing carbon dioxide.At this time, the control logic for the mode 1 may be as shown in FIG. 4.In practical applications, since a change in the circulating flow rate of the CO2-rich phase has a greater influence on a two-phase interface, the position of a two-phase interface in a second chamber can be controlled based on an interface controller and a heavy-phase flow controller, and the flow rate of the light phase solution can be controlled based on a light-phase flow controller, and a specific control process can refer to the foregoing contents, which will not be described in detail here.Step (2), in response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, the first conveying pipeline is closed, the second conveying pipeline is opened, and the light phase solution is controlled to be conveyed to the heat exchange unit via the second conveying pipeline; and the third conveying pipeline is opened, the fourth conveying pipeline is closed, and the heavy phase solution is controlled to be conveyed to the absorbent mixing unit via the third conveying pipeline. During this control process, the fifth conveying pipeline and the sixth conveying pipeline are kept closed.This step (2) corresponds to a mode 2, and a specific control process can refer to the foregoing contents, which will not be described in detail here.In the case where the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer, controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline specifically includes controlling the light phase solution to be conveyed to the first heat exchanger via the second conveying pipeline; and controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline specifically includes controlling the heavy phase solution to be conveyed to the second mixer via the third conveying pipeline.In the first heat exchanger, the CO2-rich phase exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The CO2-rich phase after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the second mixer. In the second mixer, the CO2-lean phase and the lean liquid are mixed to obtain an absorbent, which is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.At this time, the control logic for the mode 2 may be as shown in FIG. 5.In practical applications, since the change in the circulating flow rate of the CO2-rich phase has a greater influence on the two-phase interface, the position of the two-phase interface in the second chamber can be controlled based on the interface controller and the light-phase flow controller, and the flow rate of the heavy phase solution can be controlled based on the heavy-phase flow controller, and a specific control process can refer to the foregoing contents, which will not be described in detail here.Step (3), in response to an absorbent being a single-phase absorbent, the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline are closed, the fifth conveying pipeline is opened, and the solution in a first chamber is controlled to be conveyed to the heat exchange unit. During this control process, the sixth conveying pipeline is kept closed.This step (3) corresponds to a mode 3, and a specific control process can refer to the foregoing contents, which will not be described in detail here.In the heat exchange unit, a single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the absorbent mixing unit. The lean liquid obtained in the absorbent mixing unit is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.In the case where the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer, controlling the solution in the first chamber to be conveyed to the heat exchange unit specifically includes controlling the solution in the first chamber to be conveyed to the first heat exchanger and the second heat exchanger.In the first heat exchanger, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the first mixer and the second mixer. At the same time, in the second heat exchanger, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the first mixer and the second mixer. The lean liquid obtained in the first mixer and the second mixer is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.At this time, the control logic for the mode 3 may be as shown in FIG. 6.In practical applications, the liquid level in the first chamber can also be controlled based on a liquid level controller and a single-phase flow controller to maintain stability of the liquid level. For example, a normal liquid level can be set, and when the measured liquid level is greater than the normal liquid level, the opening of a third flow regulating valve can be controlled to increase; and when the measured liquid level is less than the normal liquid level, the opening of the third flow regulating valve may be controlled to decrease. The normal liquid level can be determined based on the total flow rate of the absorption liquid and the residence time of the absorption liquid in the absorption tower.Step (4), in response to the second chamber containing a single-phase absorption liquid, the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline are closed, the fifth conveying pipeline and the sixth conveying pipeline are opened, and the solution in the bottom section of the absorption tower is controlled to be conveyed to the heat exchange unit.In the case where the absorbent is a phase-change absorbent, when there is the single-phase absorption liquid in the second chamber (which can be characterized by the liquid level in the second chamber being equal to the two-phase interface position and not equal to zero), it indicates that a phase-separation result in the second chamber is that no phase-separation occurs and the absorbent remains single phase, i.e., the solution in the bottom section of the absorption tower in this period is the single-phase absorption liquid. In this case, a mode selection controller selects a mode 4 (a trigger signal for the mode 4 may be that the two-phase interface position in the second chamber is equal to the liquid level and not equal to zero) and triggers the following control process:the first conveying pipeline, the second conveying pipeline, the third conveying pipeline and the fourth conveying pipeline are closed, the fifth conveying pipeline and the sixth conveying pipeline are opened, and the solution in the bottom section of the absorption tower (i.e., the solution in the first chamber and the second chamber) is controlled to be conveyed to the heat exchange unit.In the heat exchange unit, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the absorbent mixing unit. The lean liquid obtained in the absorbent mixing unit is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.In the case where the heat exchange unit includes a first heat exchanger and a second heat exchanger, and the absorbent mixing unit includes a first mixer and a second mixer, controlling the solution in the bottom section of the absorption tower to be conveyed to the heat exchange unit specifically includes controlling the solution in the bottom section of the absorption tower to be conveyed to the first heat exchanger and the second heat exchanger.In the first heat exchanger, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the first mixer and the second mixer. At the same time, in the second heat exchanger, the single-phase absorption liquid exchanges heat with the high-temperature lean liquid withdrawn from the bottom section of the regenerator. The single-phase absorption liquid after heat exchange is further fed into the regenerator for carbon dioxide desorption, and the lean liquid with reduced temperature after heat exchange is further fed into the first mixer and the second mixer. The lean liquid obtained in the first mixer and the second mixer is further conveyed to the absorption tower to continue to participate in the reaction of absorbing carbon dioxide.At this time, the control logic for the mode 4 may be as shown in FIG. 7.In practical applications, the liquid level in the bottom section of the absorption tower can also be controlled based on the liquid level controller and the single-phase flow controller to maintain stability of the liquid level. For example, a normal liquid level can be set, and when the measured liquid level is greater than the normal liquid level, the opening of the third flow regulating valve can be controlled to increase; and when the measured liquid level is less than the normal liquid level, the opening of the third flow regulating valve may be controlled to decrease. The normal liquid level can be determined based on the total flow rate of the absorption liquid and the residence time of the absorption liquid in the absorption tower.It can be understood that based on the control method for the carbon dioxide capture system provided in the above embodiment of the present application, the carbon dioxide capture system can be made applicable not only to two phase-separation scenarios generated by using the phase-change absorbent, i.e., the CO2-lean phase being a heavy phase and the CO2-rich phase being a light phase and the CO2-lean phase being a light phase and the CO2-rich phase being a heavy phase, but also to the non-phase-separation scenarios generated by using the phase-change absorbent, and is further applicable to the scenario where the single-phase absorbent is used. Also, automatic control can be realized, improving control efficiency and reliability and safety of the system.In addition, the carbon dioxide capture system and the control method therefor provided in the embodiments of the present application also enable the system to have lower energy consumption. This is due to the fact that after the controllability of the phase-change absorption is enhanced, the flow rate of a rich liquid participating in the regenerative desorption can be controlled and the energy consumption of the regenerative desorption can be maintained at a lower level, thereby allowing the carbon dioxide capture system to operate at a lower energy consumption.Hereinafter, the solutions provided above in the present application will be described with reference to specific embodiments. It should be understood that the following embodiments are merely specific embodiments and shall not constitute undue limitations to the solutions of the present application.Carbon dioxide capture systems corresponding to Embodiments 1 to 4 described below are carbon dioxide capture systems including a fifth conveying pipeline and a sixth conveying pipeline, and a heat exchange unit includes a first heat exchanger and a second heat exchanger, and an absorbent mixing unit includes a first mixer and a second mixer. Wherein a packing section of an absorption tower has a diameter of 5200 mm, a bottom section of the absorption tower has a diameter of 7000 mm, a first baffle is 2500 mm away from a left tower wall, the first baffle has a height of 5800 mm, an upper interface meter port has a height of 5400 mm, a lower interface meter port has a height of 300 mm, a first light phase outlet has a height of 4800 mm, a second light phase outlet has a height of 4300 mm, a position where a detection port corresponding to a first carbon dioxide detection device is formed has a height of 5000 mm, and a position where a detection port corresponding to a second carbon dioxide detection device is formed has a height of 500 mm. The first carbon dioxide detection device and the second carbon dioxide detection device are chromatographic online detection instruments.Embodiment 1An absorbent is a phase-change absorbent, and the phase-change absorbent includes 50% by mass a phase separating agent component diethylethanolamine (DEEA), 25% by mass a main absorbent component monoethanolamine (MEA) and 25% by mass water.An absorption liquid formed by the phase-change absorbent after absorbing carbon dioxide overflows from a first chamber of an absorption tower to a second chamber and is separated into a light phase solution and a heavy phase solution by a phase-separation device in the second chamber.It is detected that the mass content of carbon dioxide in the light phase solution is 1.6 wt%, the mass content of carbon dioxide in the heavy phase solution is 8.2 wt%, the mass content of carbon dioxide in the light phase solution is smaller than that in the heavy phase solution, a mode 1 is triggered, and the following control process is triggered:a first conveying pipeline is opened, a second conveying pipeline is closed, and the light phase solution is controlled to be conveyed to a first mixer via the first conveying pipeline; and a third conveying pipeline is closed, a fourth conveying pipeline is opened, and the heavy phase solution is controlled to be conveyed to a first heat exchanger via the fourth conveying pipeline. During this control process, a fifth conveying pipeline and a sixth conveying pipeline are kept closed.The highest two-phase interface position of the second chamber is set to 3600 mm, the lowest two-phase interface position is set to 3000 mm, and a normal two-phase interface position is set to 3300 mm. When the measured two-phase interface position is not equal to 3300 mm, an interface controller and a heavy-phase flow controller are triggered to perform cascade control: when the measured two-phase interface position is higher than 3300 mm, the opening of a second flow regulating valve increases; and when the measured two-phase interface position is lower than 3300 mm, the opening of the second flow regulating valve decreases until the measured two-phase interface position is adjusted to be equal to or approximately equal to 3300 mm.It is detected that the flow rate of the heavy phase solution is 228 m3 / h, the flow rate of the phase-change absorbent at an absorbent inlet of the absorption tower is 380 m3 / h, and a light-phase flow controller controls a first flow regulating valve such that flow rate of light phase solution = flow rate of absorbent-flow rate of heavy phase solution = 152 m3 / h.It is calculated that the regeneration energy consumption of carbon dioxide after stable operation is 2.2 GJ / tCO2 when the carbon dioxide capture system provided in this embodiment adopts the above control.Embodiment 2An absorbent is a phase-change absorbent, and the phase-change absorbent includes 50% by mass a phase separating agent component sulfolane, 13% by mass a main absorbent component monoethanolamine (MEA), 22% by mass 2-amino-2-methyl-1-propanol (AMP) and 15% by mass water.An absorption liquid formed by the phase-change absorbent after absorbing carbon dioxide overflows from a first chamber of an absorption tower to a second chamber and is separated into a light phase solution and a heavy phase solution by a phase-separation device in the second chamber.It is detected that the mass content of carbon dioxide in the light phase solution is 7.7 wt%, the mass content of carbon dioxide in the heavy phase solution is 1.5 wt%, the mass content of carbon dioxide in the light phase solution is greater than that in the heavy phase solution, a mode 2 is triggered, and the following control process is triggered:a first conveying pipeline is closed, a second conveying pipeline is opened, and the light phase solution is controlled to be conveyed to a first heat exchanger via the second conveying pipeline; and a third conveying pipeline is opened, a fourth conveying pipeline is closed, and the heavy phase solution is controlled to be conveyed to a second mixer via the third conveying pipeline. During this control process, a fifth conveying pipeline and a sixth conveying pipeline are kept closed.The highest two-phase interface position of the second chamber is set to 4100 mm, the lowest two-phase interface position is set to 3700 mm, and a normal two-phase interface position is set to 3900 mm. When the measured two-phase interface position is not equal to 3900 mm, an interface controller and a light-phase flow controller are triggered to perform cascade control: when the measured two-phase interface position is higher than 3900 mm, the opening of a first flow regulating valve decreases; and when the measured two-phase interface position is lower than 3900 mm, the opening of the first flow regulating valve increases until the measured two-phase interface position is adjusted to be equal to or approximately equal to 3900 mm.It is detected that the flow rate of the light phase solution is 247 m3 / h, the flow rate of the phase-change absorbent at an absorbent inlet of the absorption tower is 355 m3 / h, and a heavy-phase flow controller controls a second flow regulating valve such that flow rate of heavy phase solution = flow rate of absorbent-flow rate of light phase solution = 108 m3 / h.It is calculated that the regeneration energy consumption of carbon dioxide after stable operation is 2.1 GJ / tCO2 when the carbon dioxide capture system provided in this embodiment adopts the above control.Embodiment 3An absorbent is a phase-change absorbent, and the composition of the phase-change absorbent is the same as that in Embodiment 2.It is detected that the measured two-phase interface position in a second chamber is 5500 mm, a measured liquid level in the second chamber is 5500 mm, the two-phase interface position is equal to the liquid level and not equal to zero, a mode 4 is triggered, and the following control process is triggered:a first conveying pipeline, a second conveying pipeline, a third conveying pipeline and a fourth conveying pipeline are closed, a fifth conveying pipeline and a sixth conveying pipeline are opened, and the solution in the bottom section of an absorption tower is controlled to be conveyed to a first heat exchanger and a second heat exchanger.The highest liquid level of a first chamber is set at 4500 mm, the lowest liquid level is set at 500 mm, and a normal liquid level is set at 2600 mm. When the measured liquid level is not equal to 2600 mm, a liquid level controller and a single-phase flow controller are triggered for cascade control: when the measured liquid level is higher than 2600 mm, the opening of a third flow regulating valve is increased, and when the measured liquid level is lower than 2600 mm, the opening of the third flow regulating valve is decreased until the measured liquid level is adjusted to be equal to or approximately equal to 2600 mm.It is calculated that the regeneration energy consumption of carbon dioxide after stable operation is 2.4 GJ / tCO2 when the carbon dioxide capture system provided in this embodiment adopts the above control.Embodiment 4An absorbent is a single-phase absorbent, and the single-phase absorbent includes 13% by mass monoethanolamine (MEA), 22% by mass 2-amino-2-methyl-1-propanol (AMP) and 65% by mass water.An absorption liquid formed by the single-phase absorbent after absorbing carbon dioxide remains in a first chamber and does not overflow to a second chamber.It is detected that the measured two-phase interface position in the second chamber is equal to the measured liquid level and equal to zero, a mode 3 is triggered, and the following control process is triggered:a first conveying pipeline, a second conveying pipeline, a third conveying pipeline and a fourth conveying pipeline are closed, a fifth conveying pipeline is opened, and the solution in the first chamber is controlled to be conveyed to a first heat exchanger and a second heat exchanger. During this control process, a sixth conveying pipeline is kept closed.The highest liquid level of the first chamber is set at 5500 mm, the lowest liquid level is set at 500 mm, and a normal liquid level is set at 4300 mm. When the measured liquid level is not equal to 4300 mm, a liquid level controller and a single-phase flow controller are triggered for cascade control: when the measured liquid level is higher than 4300 mm, the opening of a third flow regulating valve is increased, and when the measured liquid level is lower than 4300 mm, the opening of the third flow regulating valve is decreased until the measured liquid level is adjusted to be equal to or approximately equal to 4300 mm.It is calculated that the regeneration energy consumption of carbon dioxide after stable operation is 2.4 GJ / tCO2 when the carbon dioxide capture system provided in this embodiment adopts the above control.Thus, it can be seen that the carbon dioxide capture system provided in the embodiments of the present application can be applicable not only to two phase-separation scenarios generated by using the phase-change absorbent, i.e., the CO2-lean phase being a heavy phase and the CO2-rich phase being a light phase and the CO2-lean phase being a light phase and the CO2-rich phase being a heavy phase, but also to the non-phase-separation scenarios generated by using the phase-change absorbent, and is further applicable to the scenario where the single-phase absorbent is used. Also, the carbon dioxide capture system provided in the embodiments of the present application can achieve lower energy consumption.It should also be noted that the terms "include", "comprise" or any other variation thereof are intended to cover a non-exclusive inclusion, such that a process, method, article or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed or elements inherent to such process, method, article or apparatus. Without additional limitations, an element defined by the phrase "including a..." does not exclude the existence of additional identical elements in the process, method, article or apparatus that includes the element.The above are only embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, various modifications and variations may be made to the present application. Any modifications, equivalent replacements, improvements, and the like made within the spirit and principles of the present application shall fall within the scope of the claims of the present application.                                                                               

Claims

1. A carbon dioxide capture system, characterized by comprising an absorption tower, a first carbon dioxide detection device, a second carbon dioxide detection device, a first conveying pipeline, a second conveying pipeline, a third conveying pipeline, a fourth conveying pipeline, an absorbent mixing unit, a heat exchange unit and a regenerator, whereinthe absorption tower has a bottom section divided into a first chamber and a second chamber by a partition assembly, an absorption liquid first flows into the first chamber and then overflows from the first chamber to the second chamber via the top of the second chamber, and the second chamber is configured to perform phase-separation on the inflowing absorption liquid;a shell of the absorption tower corresponding to the second chamber is provided with a light phase outlet for discharging a light phase solution and a heavy phase outlet for discharging a heavy phase solution, and the light phase solution has a density less than that of the heavy phase solution; the first carbon dioxide detection device is configured to detect parameters related to the carbon dioxide content in the light phase solution, and the second carbon dioxide detection device is configured to detect parameters related to the carbon dioxide content in the heavy phase solution;the light phase outlet communicates with an inlet of the absorbent mixing unit through the first conveying pipeline, and the light phase outlet communicates with a first inlet of the heat exchange unit through the second conveying pipeline; the heavy phase outlet communicates with the inlet of the absorbent mixing unit through the third conveying pipeline, and the heavy phase outlet communicates with the first inlet of the heat exchange unit through the fourth conveying pipeline; anda first outlet of the heat exchange unit communicates with an inlet of the regenerator, and a second inlet of the heat exchange unit communicates with the bottom section of the regenerator; a second outlet of the heat exchange unit communicates with an inlet of the absorbent mixing unit, and the outlet of the absorbent mixing unit communicates with an absorbent inlet of the absorption tower.

2. The carbon dioxide capture system according to claim 1, characterized in that the bottom of the first chamber is provided with a first outlet, and the carbon dioxide capture system further comprises a fifth conveying pipeline; andthe first outlet of the first chamber communicates with the first inlet of the heat exchange unit through the fifth conveying pipeline.

3. The carbon dioxide capture system according to claim 2, characterized in that the bottom of the first chamber is further provided with a second outlet, the bottom of the second chamber is provided with a third outlet, and the carbon dioxide capture system further comprises a sixth conveying pipeline; andthe second outlet of the first chamber communicates with the third outlet of the second chamber through the sixth conveying pipeline.

4. The carbon dioxide capture system according to claim 3, characterized in that the shell of the absorption tower corresponding to the second chamber is further provided with an interface detection device.

5. The carbon dioxide capture system according to claim 1, characterized in that the absorption tower comprises a packing section and a bottom section, the bottom section having a diameter greater than that of the packing section.

6. The carbon dioxide capture system according to claim 1, characterized in that the partition assembly comprises a first baffle and a second baffle;the first baffle extends from a base of the bottom section of the absorption tower to a packing section of the absorption tower for dividing the bottom section of the absorption tower into the first chamber and the second chamber;the second baffle extends from the shell of the absorption tower corresponding to the top of the second chamber to the top of the first chamber for covering the top of the second chamber; anda flow passage for the absorption liquid is defined between the first baffle and the second baffle.

7. The carbon dioxide capture system according to claim 1, characterized in that a phase-separation device is further disposed in the second chamber.

8. The carbon dioxide capture system according to claim 4, characterized in that the heat exchange unit comprises a first heat exchanger and a second heat exchanger;the light phase outlet communicates with a first inlet of the first heat exchanger through the second conveying pipeline, the heavy phase outlet communicates with the first inlet of the first heat exchanger through the fourth conveying pipeline, and the first outlet of the first chamber communicates with the first inlet of the first heat exchanger and a first inlet of the second heat exchanger through the fifth conveying pipeline;both a first outlet of the first heat exchanger and a first outlet of the second heat exchanger communicate with the inlet of the regenerator, and both a second inlet of the first heat exchanger and a second inlet of the second heat exchanger communicate with the bottom section of the regenerator; andboth a second outlet of the first heat exchanger and a second outlet of the second heat exchanger communicate with the inlet of the absorbent mixing unit.

9. The carbon dioxide capture system according to claim 8, characterized in that the absorbent mixing unit comprises a first mixer and a second mixer;the light phase outlet communicates with an inlet of the first mixer through the first conveying pipeline, and the heavy phase outlet communicates with an inlet of the second mixer through the third conveying pipeline; andthe second outlet of the first heat exchanger communicates with both the inlet of the first mixer and the inlet of the second mixer, and the second outlet of the second heat exchanger communicates with both the inlet of the first mixer and the inlet of the second mixer.

10. The carbon dioxide capture system according to claim 4, characterized in that a first flow meter and a first flow regulating valve are disposed on the second conveying pipeline; anda second flow meter and a second flow regulating valve are disposed on the fourth conveying pipeline.

11. The carbon dioxide capture system according to claim 4, characterized in that a liquid level detection device is disposed on a shell of the absorption tower corresponding to the first chamber, and a third flow meter and a third flow regulating valve are disposed on the fifth conveying pipeline.

12. A control method for the carbon dioxide capture system according to any one of claims 1 to 11, characterized by comprising:in response to the carbon dioxide content in the light phase solution being less than that in the heavy phase solution, opening the first conveying pipeline, closing the second conveying pipeline, and controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline; and closing the third conveying pipeline, opening the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline; andin response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, closing the first conveying pipeline, opening the second conveying pipeline, and controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline; and opening the third conveying pipeline, closing the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline.

13. A control method for the carbon dioxide capture system according to any one of claims 1 to 11, characterized in that the bottom of the first chamber is provided with a first outlet, the carbon dioxide capture system further comprises a fifth conveying pipeline, the first outlet of the first chamber communicates with a first inlet of the heat exchange unit through the fifth conveying pipeline, and the control method comprises:in response to the carbon dioxide content in the light phase solution being less than that in the heavy phase solution, opening the first conveying pipeline, closing the second conveying pipeline, and controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline; and closing the third conveying pipeline, opening the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline;in response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, closing the first conveying pipeline, opening the second conveying pipeline, and controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline; and opening the third conveying pipeline, closing the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline; andin response to an absorbent being a single-phase absorbent, closing the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline, opening the fifth conveying pipeline, and controlling the solution in the first chamber to be conveyed to the heat exchange unit.

14. The control method according to claim 13, characterized in that the heat exchange unit comprises a first heat exchanger and a second heat exchanger, and the absorbent mixing unit comprises a first mixer and a second mixer;controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline comprises:controlling the light phase solution to be conveyed to the first mixer via the first conveying pipeline;controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline comprises:controlling the heavy phase solution to be conveyed to the first heat exchanger via the fourth conveying pipeline;controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline comprises:controlling the light phase solution to be conveyed to the first heat exchanger via the second conveying pipeline;controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline comprises:controlling the heavy phase solution to be conveyed to the second mixer via the third conveying pipeline; andcontrolling the solution in the first chamber to be conveyed to the heat exchange unit comprises:controlling the solution in the first chamber to be conveyed to the first heat exchanger and the second heat exchanger.

15. A control method for the carbon dioxide capture system according to any one of claims 1 to 11, characterized in that the bottom of the first chamber is provided with a first outlet and a second outlet, the bottom of the second chamber is provided with a third outlet, and the carbon dioxide capture system further comprises a fifth conveying pipeline and a sixth conveying pipeline; the first outlet of the first chamber communicates with a first inlet of a heat exchange unit through the fifth conveying pipeline, and the second outlet of the first chamber communicates with the third outlet of the second chamber through the sixth conveying pipeline, and the control method comprises:in response to the carbon dioxide content in the light phase solution being less than that in the heavy phase solution, opening the first conveying pipeline, closing the second conveying pipeline, and controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline; and closing the third conveying pipeline, opening the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline;in response to the carbon dioxide content in the light phase solution being greater than that in the heavy phase solution, closing the first conveying pipeline, opening the second conveying pipeline, and controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline; and opening the third conveying pipeline, closing the fourth conveying pipeline, and controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline;in response to an absorbent being a single-phase absorbent, closing the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline, opening the fifth conveying pipeline, and controlling the solution in the first chamber to be conveyed to the heat exchange unit; andin response to the second chamber containing a single-phase absorption liquid closing the first conveying pipeline, the second conveying pipeline, the third conveying pipeline, and the fourth conveying pipeline, opening the fifth conveying pipeline and the sixth conveying pipeline, and controlling the solution in the bottom section of the absorption tower to be conveyed to the heat exchange unit.

16. The control method according to claim 15, characterized in that the heat exchange unit comprises a first heat exchanger and a second heat exchanger, and the absorbent mixing unit comprises a first mixer and a second mixer;controlling the light phase solution to be conveyed to the absorbent mixing unit via the first conveying pipeline comprises:controlling the light phase solution to be conveyed to the first mixer via the first conveying pipeline;controlling the heavy phase solution to be conveyed to the heat exchange unit via the fourth conveying pipeline comprises:controlling the heavy phase solution to be conveyed to the first heat exchanger via the fourth conveying pipeline;controlling the light phase solution to be conveyed to the heat exchange unit via the second conveying pipeline comprises:controlling the light phase solution to be conveyed to the first heat exchanger via the second conveying pipeline;controlling the heavy phase solution to be conveyed to the absorbent mixing unit via the third conveying pipeline comprises:controlling the heavy phase solution to be conveyed to the second mixer via the third conveying pipeline;controlling the solution in the first chamber to be conveyed to the heat exchange unit comprises:controlling the solution in the first chamber to be conveyed to the first heat exchanger and the second heat exchanger; andcontrolling the solution in the bottom section of the absorption tower to be conveyed to the heat exchange unit comprises:controlling the solution in the bottom section of the absorption tower to be conveyed to the first heat exchanger and the second heat exchanger.

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