Carbon dioxide capture device and carbon dioxide capture method

Abstract

The application relates to the technical field of carbon dioxide capture, and provides a carbon dioxide capture device and a carbon dioxide capture method. The carbon dioxide capture method comprises the following steps: feeding raw gas containing carbon dioxide into a cut-off side of an inorganic separation membrane to perform first separation treatment, and the carbon dioxide in the raw gas penetrates into a penetration side through the inorganic separation membrane; and a sweep gas stream is used to sweep the penetration side of the inorganic separation membrane to form a penetration gas containing carbon dioxide, and the sweep gas stream comprises ammonia and water vapor. The sweep gas stream containing ammonia and water is used to sweep the inorganic separation membrane, so that the separation efficiency and the recovery rate of the inorganic separation membrane are effectively improved.

Description

Technical Field

[0001] This application relates to the field of carbon dioxide capture technology, and in particular to a carbon dioxide capture device and a carbon dioxide capture method. Background Technology

[0002] The principle of carbon dioxide separation using membranes is based on the difference in diffusion rates of different gases within a membrane. Driven by pressure, the components in a gas mixture diffuse at different rates within an inorganic membrane, thus achieving selective separation. Compared to polymer membranes, inorganic membranes offer advantages such as long service life, high temperature resistance, high pressure resistance, and good stability, making them promising for various applications. However, limitations in single-stage membrane separation performance necessitate increasing the separation pressure and membrane area to improve the carbon dioxide recovery rate of inorganic membranes. Consequently, inorganic membrane separation of carbon dioxide is costly and has a low recovery rate. Summary of the Invention

[0003] Therefore, it is necessary to provide a carbon dioxide capture device and method with high recovery rate and low cost.

[0004] In a first aspect, this application provides a carbon dioxide capture method, the carbon dioxide capture method comprising:

[0005] A feed gas containing carbon dioxide is passed into the retrieval side of an inorganic separation membrane for a first separation process, wherein the carbon dioxide in the feed gas permeates through the inorganic separation membrane into the permeation side; and...

[0006] The permeate side of the inorganic separation membrane is purged with a purge gas stream to form a permeate gas containing carbon dioxide. The purge gas stream includes ammonia and water vapor.

[0007] In some embodiments, the molar ratio of ammonia to water vapor in the purge gas flow is 1:(5~10).

[0008] In some embodiments, the temperature of the purge airflow is 100°C to 200°C.

[0009] In some embodiments, the ratio of the volumetric flow rate of the purge gas to the volumetric flow rate of the feed gas is (0.2~0.6):1.

[0010] In some embodiments, the gas pressure on the retrieval side of the inorganic separation membrane is 0.3 MPa to 1.0 MPa, and the temperature is 100°C to 200°C.

[0011] In some embodiments, the gas pressure on the permeation side of the inorganic separation membrane is 0.08 MPa to 0.12 MPa, and the temperature is 100°C to 200°C.

[0012] In some embodiments, the carbon dioxide capture method further includes: subjecting the permeate gas to a second separation process, the second separation process being used to separate the permeate gas into carbon dioxide and an ammonia-containing solution.

[0013] Optionally, the temperature of the second separation process is 20℃~25℃, and the pressure is 0.08MPa~0.12MPa.

[0014] In some embodiments, the carbon dioxide capture method further includes: performing a third separation treatment on the ammonia-containing solution, the third separation treatment being used to separate the ammonia-containing solution into carbon dioxide and an ammonia solution.

[0015] Optionally, the temperature of the third separation process is 50℃~70℃, and the pressure is 0.08MPa~0.12MPa.

[0016] Optionally, the ammonia solution produced by the third separation process is recycled as a raw material for the purge gas stream.

[0017] In some embodiments, the carbon dioxide capture method further includes a drying process to dry and dehydrate the carbon dioxide produced by the second separation process.

[0018] Optionally, the drying process further dries and dehydrates the carbon dioxide produced by the third separation process.

[0019] Secondly, this application provides a carbon dioxide capture device, the carbon dioxide capture device comprising:

[0020] A first separator, comprising a housing and an inorganic separation membrane disposed within the housing, the inorganic separation membrane dividing the housing into a retention chamber and a permeation chamber, the retention chamber being used to introduce a feed gas containing carbon dioxide; and...

[0021] A purger is connected to the permeation chamber and is used to purge the side of the inorganic separation membrane near the permeation chamber to form a permeation gas containing carbon dioxide. The purge gas flow blown out by the purger includes ammonia and water vapor.

[0022] In some embodiments, the carbon dioxide capture device further includes a second separator connected to the permeation chamber, the second separator being used to separate the permeate gas discharged from the permeation chamber to form carbon dioxide gas and an ammonia-containing solution.

[0023] In some embodiments, the carbon dioxide capture device further includes a third separator connected to the second separator, the third separator being used to separate the ammonia-containing solution to form an ammonia solution and carbon dioxide.

[0024] Optionally, the third separator is also connected to the purger, and the ammonia solution discharged from the third separator enters the purger as the raw material for the purge gas flow.

[0025] In some embodiments, the carbon dioxide capture device further includes a dryer connected to the second separator, the dryer being used to dry the carbon dioxide discharged from the second separator.

[0026] Optionally, the dryer is also connected to the third separator, and the dryer is used to dry the carbon dioxide discharged from the third separator.

[0027] Compared with traditional technologies, this application has at least the following beneficial effects:

[0028] This application employs a purge gas stream containing ammonia and water vapor to purge the permeate side of an inorganic separation membrane. The ammonia reacts with carbon dioxide in an acid-base reaction, absorbing the carbon dioxide on the permeate side and reducing its concentration. This increases the separation rate of carbon dioxide by the inorganic separation membrane, effectively improving the carbon dioxide recovery rate. Furthermore, the permeate gas formed after purging can be cooled to obtain high-purity carbon dioxide. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of a carbon dioxide capture device provided in a specific embodiment of this application.

[0030] Among them, 10-first separator; 11-inorganic separation membrane; 20-purger; 30-second separator; 40-third separator; 50-dryer. Detailed Implementation

[0031] The present application will be further described in detail below with reference to the embodiments and examples. These embodiments and examples are only for illustrating the present application and are not intended to limit the scope of the present application. The purpose of providing these embodiments and examples is to make the disclosure of the present application more thorough and comprehensive. It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various modifications or alterations without departing from the spirit of the present application, and the equivalent forms obtained also fall within the protection scope of the present application. In addition, numerous specific details are set forth in the following description to provide a fuller understanding of the present application. It should be understood that the present application can be implemented without one or more of these details.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0033] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0034] In this application, the terms "first aspect," "second aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first aspect," "second aspect," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0035] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0036] In this application, when numerical intervals (i.e., numerical ranges) are mentioned, unless otherwise specified, the distribution of selectable numerical values ​​within the numerical interval is considered continuous, and includes the two endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that numerical interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints, which is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical ranges disclosed in this application should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. The term "numerical interval" can be broadly included to include percentage intervals, ratio intervals, proportion intervals, etc.

[0037] All references to this application are incorporated herein by reference as if each document were individually incorporated herein by reference. Unless they conflict with the purpose and / or technical solution of this application, all cited references are incorporated herein by reference in their entirety and for all purposes. When references are cited in this application, the definitions of relevant technical features, terms, nouns, phrases, etc., are also incorporated herein by reference. Examples and preferred embodiments of the cited technical features may also be incorporated herein by reference, but only to the extent that they enable the implementation of this application. It should be understood that when the cited content conflicts with the description in this application, this application shall prevail or modifications shall be made adaptably to the description in this application.

[0038] In traditional techniques, the permeate side of a carbon dioxide separation membrane can be purged to enhance its separation efficiency. However, the introduction of purging gas affects the purity of carbon dioxide on the permeate side, resulting in only a slight improvement in separation efficiency when using carbon dioxide gas for purging.

[0039] Based on this, the first aspect of this application provides a carbon dioxide capture method, the carbon dioxide capture method comprising:

[0040] A feed gas containing carbon dioxide is passed into the retrieval side of an inorganic separation membrane for a first separation process, wherein the carbon dioxide in the feed gas permeates through the inorganic separation membrane into the permeation side; and...

[0041] The permeate side of the inorganic separation membrane is purged with a purge gas stream to form a permeate gas containing carbon dioxide. The purge gas stream includes ammonia and water vapor.

[0042] This application employs a purge gas stream containing ammonia and water vapor to purge the permeate side of an inorganic separation membrane. The ammonia reacts with carbon dioxide in an acid-base reaction, absorbing the carbon dioxide on the permeate side and reducing its concentration. This increases the separation rate of carbon dioxide by the inorganic separation membrane, effectively improving the carbon dioxide recovery rate. Furthermore, the carbon dioxide in the permeate gas formed after purging can be obtained as high-purity carbon dioxide simply by cooling it.

[0043] It should be noted that the inorganic separation membrane in this application is a non-promoted transfer membrane, capable of separating carbon dioxide by utilizing the permeability differences of different gas molecules in the mold pores. For example, the inorganic separation membrane can be at least one of carbon molecular sieve membranes, zeolite membranes, porous ceramic membranes, and MOF membranes. It is understood that this application can select a suitable inorganic separation membrane based on the composition of the feed gas.

[0044] In some embodiments, the volume percentage of carbon dioxide in the raw gas is 5% to 50%, for example, it can be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45% or 50%.

[0045] In some embodiments, the molar ratio of ammonia to water vapor in the purge gas stream is 1:(5~10), for example, it can be 1:5, 1:6, 1:7, 1:8, 1:9 or 1:10. The above-mentioned selection of the molar ratio of ammonia to water vapor in the purge gas stream effectively ensures the purging effect and avoids the problem of ammonia escape during desorption.

[0046] In some embodiments, the temperature of the purge gas flow is 100℃~200℃, for example, it can be 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, 190℃ or 200℃. The purge gas flow temperature selected as described above in this application not only effectively ensures the stability of the inorganic separation membrane, but also provides a good purging effect.

[0047] In some embodiments, the ratio of the volumetric flow rate of the purge gas to the volumetric flow rate of the feed gas is (0.2~0.6):1. The selection of the purge gas volumetric flow rate as described above in this application can improve separation efficiency and avoid membrane surface concentration polarization and dilution of the product gas CO2 concentration.

[0048] In some embodiments, the gas pressure on the retrieval side of the inorganic separation membrane is 0.3 MPa to 1.0 MPa, for example, it can be 0.3 MPa, 0.4 MPa, 0.5 MPa, 0.6 MPa, 0.7 MPa, 0.8 MPa, 0.9 MPa or 1.0 MPa.

[0049] In some embodiments, the gas temperature on the retrieval side of the inorganic separation membrane is 100°C to 200°C, for example, it can be 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C or 200°C.

[0050] In some embodiments, the gas pressure on the permeate side of the inorganic separation membrane is 0.08 MPa to 0.12 MPa. Optionally, it is 0.1 MPa.

[0051] In some embodiments, the gas temperature on the permeation side of the inorganic separation membrane is 100°C to 200°C, for example, it can be 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C or 200°C.

[0052] In some embodiments, the carbon dioxide capture method further includes: subjecting the permeate gas to a second separation process, the second separation process being used to separate the permeate gas into carbon dioxide and an ammonia-containing solution. This application uses the second separation process to separate the purge gas mixed in the permeate gas, thereby obtaining high-purity carbon dioxide. It is understood that the ammonia-containing solution contains some carbon dioxide as well as ammonium carbonate or ammonium bicarbonate salts.

[0053] Optionally, the temperature of the second separation process is 20℃~25℃, for example, 20℃, 21℃, 22℃, 23℃, 24℃ or 25℃. The pressure of the second separation process is 0.08MPa~0.12MPa, optionally 0.1MPa. Since the permeate gas contains carbon dioxide, ammonia and water vapor, after cooling, the ammonia dissolves in water to form an ammonia solution, and reacts with some of the carbon dioxide to form an ammonium bicarbonate solution. The remaining carbon dioxide gas can be dried to obtain high-purity carbon dioxide.

[0054] In some embodiments, the carbon dioxide capture method further includes: performing a third separation treatment on the ammonia-containing solution, the third separation treatment being used to separate the ammonia-containing solution into carbon dioxide and an ammonia solution. Since the ammonia-containing solution may contain dissolved carbon dioxide or carbonates, the third separation method separates the carbon dioxide from the ammonium bicarbonate solution, further improving the carbon dioxide recovery rate.

[0055] Optionally, the temperature of the third separation process is 50℃~70℃, for example, 50℃, 55℃, 60℃, 65℃, or 70℃. The pressure is 0.08MPa~0.12MPa, optionally 0.1MPa. By selecting the temperature and pressure of the third separation process as described above, this application enables the ammonium bicarbonate solution to decompose into carbon dioxide gas and ammonia solution, thereby further separating the carbon dioxide and effectively improving the carbon dioxide recovery rate.

[0056] Optionally, the third separation process employs a desorption separation method.

[0057] Optionally, the ammonia solution produced in the third separation process is heated to form ammonia gas and water vapor, which are then recycled as raw materials for the purge gas stream. This application recycles the ammonia solution produced in the third separation process and uses the ammonia gas and water vapor formed after heating the ammonia solution as raw materials for the purge gas stream, thereby achieving recycling and reducing raw material costs. It is understood that when the concentration of the ammonia solution produced in the third separation process does not meet the usage requirements, additional ammonia water can be introduced for adjustment.

[0058] In some embodiments, the carbon dioxide capture method further includes a drying process, wherein the drying process dries and dehydrates the carbon dioxide produced by the second separation process.

[0059] Optionally, the drying process further dries and dehydrates the carbon dioxide produced by the third separation process.

[0060] For example, the above-described carbon dioxide capture method is provided, comprising the following steps:

[0061] S1. The pressurized raw gas is introduced into the retrieval side of the inorganic separation membrane. The temperature of the raw gas is 100℃~200℃, and the pressure on the retrieval side of the inorganic separation membrane is 0.3MPa~1.0MPa.

[0062] S2. The permeate side of the inorganic separation membrane is purged with a purge gas flow. The purge gas flow includes ammonia and water vapor in a molar ratio of 1:(5~10). The volume ratio of the flow rate of the purge gas flow to the flow rate of the raw material gas flow in step S1 is (0.2~0.6):1, and the temperature is 100℃~200℃. The permeate side pressure of the inorganic separation membrane is 0.08MPa~0.12MPa.

[0063] S3. Carbon dioxide passing through the inorganic separation membrane is mixed with the purge gas to form permeate gas. The permeate gas is then introduced into the second separator for separation. The temperature of the second separator is 20℃~25℃ and the pressure is 0.08MPa~0.12MPa, forming an ammonia-containing solution and carbon dioxide.

[0064] S4. The ammonia-containing solution generated in step S3 is passed into the third separator. The temperature of the third separator is 50℃~70℃ and the pressure is 0.08MPa~0.12MPa, forming an ammonia solution and carbon dioxide.

[0065] The carbon dioxide produced in steps S5, S3, and S4 is dried to obtain the carbon dioxide product.

[0066] S6. The ammonia solution produced in step S4 is heated and then used as a raw material for the purging gas stream, and is recycled.

[0067] The second aspect of this application provides a carbon dioxide capture device, such as... Figure 1 As shown, the carbon dioxide capture device includes:

[0068] A first separator 10 includes a housing and an inorganic separation membrane 11 disposed within the housing. The inorganic separation membrane 11 divides the housing into a retention chamber and a permeation chamber. The retention chamber is used to introduce a feed gas containing carbon dioxide.

[0069] A purger 20 is connected to the permeation chamber. The purger 20 is used to purge the side of the inorganic separation membrane 11 near the permeation chamber to form a permeation gas containing carbon dioxide. The purge gas flow blown out by the purger 20 includes ammonia and water vapor.

[0070] This application utilizes a purge gas stream containing ammonia and water vapor to purge the permeate side of an inorganic separation membrane. By reacting ammonia with carbon dioxide, the carbon dioxide concentration on the permeate side is effectively reduced, thereby improving the separation efficiency of the inorganic separation membrane. Furthermore, ammonia and water vapor are easily separated from the permeate gas; for example, ammonia and water can be separated through cooling treatment to obtain high-purity carbon dioxide.

[0071] In some embodiments, the carbon dioxide capture device further includes a second separator 30 connected to the permeation chamber. The second separator 30 is used to separate the permeate gas discharged from the permeation chamber to form carbon dioxide gas and an ammonia-containing solution. Optionally, the second separator 30 can be a cooling separation tank, which separates the carbon dioxide in the permeate gas into a gaseous state and the ammonia and water into a liquid state by cooling, thereby achieving the separation of carbon dioxide.

[0072] In some embodiments, the carbon dioxide capture device further includes a third separator 40 connected to the second separator 30. The third separator 40 is used to separate the ammonia-containing solution to form an ammonia solution and carbon dioxide. Optionally, the third separator 40 can be a desorption tower, which uses heating desorption separation to desorb carbon dioxide from the ammonia-containing solution (containing ammonium bicarbonate, etc.). Furthermore, under heating, carbonates such as ammonium carbonate also decompose, thereby improving the carbon dioxide recovery rate.

[0073] Optionally, the third separator 40 is also connected to the purger 20, and the ammonia solution discharged from the third separator 40 enters the purger 20 as the raw material for the purge gas flow. This application connects the ammonia solution generated by the third separator 40 to the purger 20, achieving the recycling and regeneration of the purge gas flow and reducing raw material costs.

[0074] In some embodiments, the carbon dioxide capture device further includes a dryer 50 connected to the second separator 30, the dryer 50 being used to dry the carbon dioxide discharged from the second separator 30.

[0075] Optionally, the dryer 50 is also connected to the third separator 40, and the dryer 50 is used to dry the carbon dioxide discharged from the third separator 40.

[0076] The embodiments of this application will be described in detail below with reference to examples. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of this application. For experimental methods in the following embodiments where specific conditions are not specified, please refer to the guidelines given in this application, or follow experimental manuals or conventional conditions in the art, or follow the conditions recommended by the manufacturer, or refer to experimental methods known in the art.

[0077] In the following examples and comparative examples, the raw gas composition, by volume percentage, is 15 wt% carbon dioxide and 85 wt% nitrogen. A carbon molecular sieve membrane is used as the inorganic separation membrane. The second separator is a cooling separation tank, and the third separator is a desorption tower.

[0078] Example 1

[0079] S1. Pressurized feed gas is introduced into the retrieval side of the inorganic separation membrane. The temperature of the feed gas is 200℃ and the pressure on the retrieval side of the inorganic separation membrane is 0.5MPa.

[0080] S2. The permeate side of the inorganic separation membrane is purged with a purge airflow. The purge airflow includes ammonia and water vapor in a molar ratio of 1:10. The volume ratio of the purge airflow flow rate to the raw material airflow flow rate in step S1 is 0.2:1, and the temperature is 200℃. The permeate side pressure of the inorganic separation membrane is 0.1MPa.

[0081] S3. Carbon dioxide passing through the inorganic separation membrane is mixed with the purge gas to form permeate gas. The permeate gas is then introduced into the second separator for separation. The temperature of the second separator is 25°C and the pressure is 0.1 MPa, forming an ammonia-containing solution (containing ammonium bicarbonate, etc.) and carbon dioxide.

[0082] S4. The ammonia-containing solution produced in step S3 is passed into the third separator. The temperature of the third separator is 70°C and the pressure is 0.1 MPa, forming an ammonia solution and carbon dioxide.

[0083] The carbon dioxide produced in steps S5, S3, and S4 is dried to obtain the carbon dioxide product.

[0084] S6. The ammonia solution produced in step S4 is heated and then used as a raw material for the purging gas stream, and is recycled.

[0085] Comparative Example 1

[0086] Carbon dioxide is recovered according to the carbon dioxide capture method of Example 1, except that a purge gas flow is not used for purging.

[0087] The carbon dioxide recovered in Example 1 and Comparative Example 1 was tested for purity and recovery rate. Specifically, the volume purity of the carbon dioxide recovered in Example 1 was 91%, and the recovery rate was 70% (single-stage membrane separation), while the volume purity of the carbon dioxide recovered in Comparative Example 1 was 90%, and the recovery rate was 60% (single-stage membrane separation). Recovery rate refers to the ratio of the recovered carbon dioxide to the carbon dioxide content in the feedstock.

[0088] In summary, this application employs a purge gas stream containing ammonia and water vapor to purge the permeate side of the inorganic separation membrane. The ammonia reacts with carbon dioxide in an acid-base reaction, absorbing the carbon dioxide on the permeate side and reducing its concentration. This increases the separation rate of carbon dioxide by the inorganic separation membrane, effectively improving the carbon dioxide recovery rate. Furthermore, the carbon dioxide in the permeate gas formed after purging is easily separated; for example, high-purity carbon dioxide can be obtained simply by cooling.

[0089] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0090] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the appended claims.

Claims

1. A method for capturing carbon dioxide, characterized in that, The carbon dioxide capture method includes: A feed gas containing carbon dioxide is passed into the retrieval side of an inorganic separation membrane for a first separation process, wherein the carbon dioxide in the feed gas permeates through the inorganic separation membrane into the permeation side; and... The permeate side of the inorganic separation membrane is purged with a purge gas stream to form a permeate gas containing carbon dioxide. The purge gas stream includes ammonia and water vapor. The molar ratio of ammonia to water vapor in the purge gas stream is 1:(5~10), the temperature of the purge gas stream is 100℃~200℃, and the volumetric flow rate of the purge gas stream to the volumetric flow rate of the raw material gas is (0.2~0.6):

1.

2. The carbon dioxide capture method as described in claim 1, characterized in that, The carbon dioxide capture method satisfies at least one of the following conditions: (1) The gas pressure on the truncation side of the inorganic separation membrane is 0.3MPa~1.0MPa and the temperature is 100℃~200℃; (2) The gas pressure on the permeation side of the inorganic separation membrane is 0.08MPa~0.12MPa and the temperature is 100℃~200℃.

3. The carbon dioxide capture method as described in claim 1 or 2, characterized in that, The carbon dioxide capture method further includes: performing a second separation process on the permeate gas, wherein the second separation process is used to separate the permeate gas into carbon dioxide and an ammonia-containing solution.

4. The carbon dioxide capture method as described in claim 3, characterized in that, The temperature of the second separation process is 20℃~25℃, and the pressure is 0.08MPa~0.12MPa.

5. The carbon dioxide capture method as described in claim 4, characterized in that, The carbon dioxide capture method further includes: performing a third separation treatment on the ammonia-containing solution, wherein the third separation treatment is used to separate the ammonia-containing solution into carbon dioxide and an ammonia solution.

6. The carbon dioxide capture method as described in claim 5, characterized in that, The temperature of the third separation process is 50℃~70℃, and the pressure is 0.08MPa~0.12MPa.

7. The carbon dioxide capture method as described in claim 5, characterized in that, The ammonia solution produced by the third separation process is recycled and reused as the raw material for the purging gas stream.

8. The carbon dioxide capture method as described in claim 5, characterized in that, The carbon dioxide capture method further includes a drying process, wherein the drying process dries and dehydrates the carbon dioxide produced by the second separation process.

9. The carbon dioxide capture method as described in claim 8, characterized in that, The drying process also involves drying and dehydrating the carbon dioxide produced in the third separation process.

10. A carbon dioxide capture device, characterized in that, The carbon dioxide capture device includes: A first separator, comprising a housing and an inorganic separation membrane disposed within the housing, the inorganic separation membrane dividing the inner cavity of the housing into a retention chamber and a permeation chamber, the retention chamber being used to introduce a feed gas containing carbon dioxide; and... A purger is connected to the permeation chamber and is used to purge the side of the inorganic separation membrane near the permeation chamber to form a permeation gas containing carbon dioxide. The purge gas flow blown out by the purger includes ammonia and water vapor. The molar ratio of ammonia to water vapor in the purge gas stream is 1:(5~10), the temperature of the purge gas stream is 100℃~200℃, and the volumetric flow rate of the purge gas stream to the volumetric flow rate of the raw material gas is (0.2~0.6):

1.

11. The carbon dioxide capture device as described in claim 10, characterized in that, The carbon dioxide capture device further includes a second separator connected to the permeation chamber. The second separator is used to separate the permeate gas discharged from the permeation chamber to form carbon dioxide gas and an ammonia-containing solution.

12. The carbon dioxide capture device as described in claim 11, characterized in that, The carbon dioxide capture device further includes a third separator connected to the second separator, the third separator being used to separate the ammonia-containing solution to form an ammonia solution and carbon dioxide.

13. The carbon dioxide capture device as described in claim 12, characterized in that, The third separator is also connected to the purger, and the ammonia solution discharged from the third separator enters the purger as the raw material for the purge gas flow.

14. The carbon dioxide capture device as described in claim 12, characterized in that, The carbon dioxide capture device further includes a dryer connected to the second separator, which is used to dry the carbon dioxide discharged from the second separator.

15. The carbon dioxide capture device as described in claim 14, characterized in that, The dryer is also connected to the third separator, and the dryer is used to dry the carbon dioxide discharged from the third separator.

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