Carbon dioxide desorption column, carbon dioxide desorption method, and decarbonization system

Abstract

This application discloses a carbon dioxide desorption tower, a carbon dioxide desorption method, and a decarbonization system, belonging to the field of chemical equipment technology. The carbon dioxide desorption tower includes a tower body, a catalytic unit, a liquid collecting device, and a reboiler. The tower body has a first receiving cavity, a first liquid inlet, a first liquid outlet, and a gas outlet; the catalytic unit is located below the first liquid inlet; the liquid collecting device divides the first receiving cavity into a first chamber and a second chamber; the reboiler has a reboiler inlet and a reboiler outlet, and the tower body has a second liquid outlet and a second liquid inlet. Liquid in the first chamber flows sequentially into the reboiler through the second liquid outlet and the reboiler inlet, and liquid in the reboiler flows sequentially into the second chamber through the reboiler outlet and the second liquid inlet; wherein, the liquid collecting device is provided with a venting section, and the first chamber and the second chamber are connected through the venting section. The carbon dioxide desorption tower of this application can improve desorption efficiency and reduce desorption energy consumption.

Description

Technical Field

[0001] This application relates to the field of chemical equipment technology, and in particular to a carbon dioxide desorption tower, a carbon dioxide desorption method, and a decarbonization system. Background Technology

[0002] With the acceleration of global industrialization, the massive combustion of fossil fuels has led to a continuous rise in the concentration of greenhouse gases such as carbon dioxide (CO2) in the atmosphere, triggering a series of severe environmental problems such as global warming and sea-level rise. The international community is increasingly focused on greenhouse gas emission reduction, and countries have set "carbon peaking" and "carbon neutrality" targets to address the challenges of climate change. Ships, as the backbone of global trade and transportation, rely heavily on fossil fuels such as heavy oil or diesel for their propulsion systems. The large amounts of carbon dioxide produced during combustion are a major source of greenhouse gas emissions from the shipping industry. With the International Maritime Organization (IMO) issuing increasingly stringent greenhouse gas emission regulations, CO2 emission reduction from ship exhaust has become an urgent task for the shipping industry to achieve green transformation and upgrading, and is also an important component of global low-carbon development. Among numerous carbon capture technologies, chemical absorption, especially the amine method using organic amine solutions as absorbents, is considered one of the carbon capture technologies suitable for engineering application on ships due to its high technological maturity and good CO2 capture efficiency.

[0003] However, applying amine-based carbon capture technology to marine environments faces the problem of excessively high energy consumption during the desorption process. Desorption is the reverse of absorption, a strongly endothermic process requiring significant thermal energy. In related technologies, the regeneration of the rich solution primarily relies on a high-temperature heat source provided by the reboiler (typically from waste heat from the ship's engines or additional fuel combustion), driving CO2 release through sensible heating and stripping. This desorption method is limited by the chemical kinetics of the solvent itself, resulting in a slow reaction rate and limited desorption efficiency. To achieve ideal regeneration results (i.e., sufficiently low residual CO2 load in the lean solution), it is usually necessary to increase the regeneration temperature or extend the residence time of the rich solution in the column. This directly leads to a persistently high heat load on the reboiler, significantly increasing the overall energy consumption of the carbon capture system. Summary of the Invention

[0004] This application provides a carbon dioxide desorption tower that can improve desorption efficiency and reduce desorption energy consumption.

[0005] Another objective of this application is to provide a method for carbon dioxide desorption.

[0006] The third objective of this application is to provide a decarbonization system.

[0007] To achieve the above objectives, according to a first aspect of this application, a carbon dioxide desorption tower is provided, comprising: The tower body has a first receiving cavity and a first liquid inlet, a first liquid outlet and a gas outlet communicating with the first receiving cavity; A catalytic unit is located below the first liquid inlet and the gas outlet, and the catalytic unit is used to carry the catalyst; A liquid collecting device is located below the catalytic unit and above the first liquid outlet, and the liquid collecting device divides the first receiving cavity into a first cavity and a second cavity; A reboiler having a reboiler inlet and a reboiler outlet, and a tower having a second outlet and a second inlet. Liquid in the first chamber flows into the reboiler sequentially through the second outlet and the reboiler inlet, and liquid in the reboiler flows into the second chamber sequentially through the reboiler outlet and the second inlet. The liquid collecting component is provided with a venting section, and the first cavity and the second cavity are connected through the venting section.

[0008] Optionally, the opening of the venting section facing the catalytic unit is located above at least a portion of the second liquid outlet.

[0009] Optionally, the liquid collecting component includes a partition, the side of which away from the vent is connected to the inner wall of the tower body; The partition is an inclined structure, and extends inclinedly from the inner wall of the tower towards the catalytic unit, forming the ventilation section.

[0010] Optionally, the liquid collecting element includes a partition and an extension that are connected to each other. The extension extends from the partition toward the catalytic unit, and the extension and the partition together enclose the venting section.

[0011] Optionally, the carbon dioxide desorption tower further includes a flow guide located between the catalytic unit and the liquid collection unit, which is used to guide liquid to the liquid collection unit.

[0012] Optionally, the flow guide includes a flow guide section, and the projection of the vent section in the height direction of the tower body is located within the range of the projection of the flow guide section in the height direction of the tower body.

[0013] Optionally, the drainage portion is provided to protrude toward the catalytic unit; and / or, The drainage component also includes a flow guide portion, which is located below the drainage component and protrudes towards the liquid collection component.

[0014] Optionally, the flow guide further includes a support portion, one end of which is connected to the flow guide portion, and the other end of which is connected to the inner wall of the tower body.

[0015] Optionally, the catalytic unit includes a packing layer and a receiving chamber, wherein the packing layer is used to support a first catalyst and the receiving chamber is used to support a second catalyst.

[0016] Optionally, the filler layer is located above the receiving chamber.

[0017] Optionally, the first catalyst and the second catalyst may be of the same type or different types. Wherein, the first catalyst is coated on the filler layer; and / or, The second catalyst is a particulate catalyst.

[0018] Optionally, the carbon dioxide desorption tower further includes a steam generator connected to the reboiler, the steam generator being used to provide a heat source for the reboiler.

[0019] According to a second aspect of this application, a carbon dioxide desorption method is provided, using a carbon dioxide desorption tower as described in any one of the above-described methods, the carbon dioxide desorption method comprising: The liquid enters the first cavity through the first inlet, flows sequentially through the catalytic unit and the liquid collection device, and then enters the reboiler for regeneration; The regenerated gas-liquid mixture enters the second chamber, the desorbed gas rises through the vent and flows out through the outlet, and the regenerated liquid flows out through the first liquid outlet.

[0020] According to a third aspect of this application, a decarbonization system is also provided, comprising a carbon dioxide absorption tower and a carbon dioxide desorption tower as described in any of the above, wherein the carbon dioxide absorption tower has a third inlet and a third outlet, the third inlet being connected to the first outlet and the third outlet being connected to the first inlet.

[0021] In the carbon dioxide desorption tower of this application embodiment, a catalytic unit is provided below the first liquid inlet and gas outlet. The catalytic unit carries the catalyst, which can lower the activation energy of the carbon dioxide desorption reaction and accelerate the desorption rate of liquid and carbon dioxide, thereby improving the desorption efficiency of the carbon dioxide desorption tower. Compared with traditional desorption towers, the carbon dioxide desorption tower of this application can achieve the same desorption rate at a lower temperature or in a shorter residence time. This can reduce the heat load of the reboiler or reduce the height and size of the carbon dioxide desorption tower, thereby reducing the energy consumption and equipment investment cost of desorption.

[0022] The first receiving chamber is divided into a first chamber and a second chamber by a liquid collecting device. The first chamber is located above the liquid collecting device and is used to contain the rich liquid to be regenerated. The second chamber is located below the liquid collecting device and is used to contain the lean liquid after regeneration and the desorbed gas. A circulation loop is formed between the reboiler and the tower body. The rich liquid drawn from the first chamber enters the reboiler for heating and regeneration. The gas-liquid mixture after reboiling returns to the second chamber for gas-liquid separation. The venting part of the liquid collecting device allows the desorbed gas to rise from the second chamber to the first chamber and exchange heat with the descending rich liquid to increase the temperature of the rich liquid, which can further promote the desorption reaction, thereby further improving the desorption efficiency of the carbon dioxide desorption tower and reducing the energy consumption of desorption.

[0023] The carbon dioxide desorption method in this application uses a carbon dioxide desorption tower. The carbon dioxide desorption method has the beneficial effects produced by the carbon dioxide desorption tower, which will not be elaborated further here.

[0024] The decarbonization system of this application embodiment includes a carbon dioxide absorption tower and a carbon dioxide desorption tower. The decarbonization system has the beneficial effects produced by the carbon dioxide desorption tower, which will not be described in detail here.

[0025] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0028] Figure 1 This is a schematic diagram of the structure of the carbon dioxide desorption tower provided in an exemplary embodiment of this disclosure; Figure 2 This is a three-dimensional structural schematic diagram of the drainage device and the liquid collection device provided in the exemplary embodiments of this disclosure from one perspective; Figure 3 This is a three-dimensional structural schematic diagram of the drainage device and liquid collection device provided in the exemplary embodiments of this disclosure from another perspective; Figure 4 This is a schematic diagram of the planar structure of the drainage component and the liquid collection component provided in the exemplary embodiments of this disclosure; Figure 5 This is a schematic diagram of the decarbonization system provided in an exemplary embodiment of this disclosure.

[0029] Explanation of reference numerals in the attached figures: 100. Carbon dioxide desorption tower; 1. Tower body; 11. First receiving cavity; 111. First chamber; 112. Second chamber; 12. First liquid inlet; 13. First liquid outlet; 14. Gas outlet; 15. Second liquid outlet; 16. Second liquid inlet; 2. Catalytic unit; 21. Packing layer; 22. Receiving box; 3. Flow guide; 31. Flow guide section; 32. Flow guide section; 33. Support section; 4. Liquid collection component; 41. Ventilation section; 42. Separator section; 43. Extension section; 5. Reboiler; 51. Reboiler inlet; 52. Reboiler outlet; 6. Steam generator; 200. Carbon dioxide absorption tower; 210. Third liquid inlet; 220. Third liquid outlet; 230. Flue gas inlet; 240. Flue gas outlet; 300. Heat exchanger; Z, Height direction. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application. In this application, unless otherwise stated, directional terms such as "up," "down," "left," and "right" generally refer to up, down, left, and right in the actual use or working state of the device, specifically the drawing directions in the accompanying drawings.

[0031] In this application, unless otherwise expressly specified and limited, the terms "connected," "linked," "stacked," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0032] This application provides a carbon dioxide desorption tower, a carbon dioxide desorption method, and a decarbonization system, which are described in detail below. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments of this application. Furthermore, in the following embodiments, the descriptions of each embodiment have their own emphasis; parts not described in detail in a certain embodiment can be referred to in the relevant descriptions of other embodiments.

[0033] According to the first aspect of this application, referring to Figure 1 One embodiment of this application provides a carbon dioxide desorption tower 100, which may include: a tower body 1, a catalytic unit 2, a liquid collection unit 4, and a reboiler 5.

[0034] Specifically, refer to Figure 1 The tower body 1 can be cylindrical, with an inner diameter of, for example, 1.2m and a height of, for example, 6m. The tower body 1 can have a first receiving cavity 11 and a first liquid inlet 12, a first liquid outlet 13, and a gas outlet 14 communicating with the first receiving cavity 11. The first liquid inlet 12 can be located at the top of the tower body 1 and on its side wall. The liquid to be regenerated can be introduced into the first receiving cavity 11 through the first liquid inlet 12. The liquid to be regenerated is, for example, a rich liquid containing carbon dioxide, such as an aqueous solution of methyldiethanolamine containing carbon dioxide. Methyldiethanolamine aqueous solution is an aqueous solution containing an amino solvent. The first liquid outlet 13 can be located at the bottom of the tower body 1. The regenerated liquid can leave the first receiving cavity 11 through the first liquid outlet 13. The regenerated liquid is the desorbed lean liquid. The gas outlet 14 can be located at the top of the tower body 1. The desorbed gas can leave the first receiving cavity 11 through the gas outlet 14. The gas is, for example, carbon dioxide or water vapor.

[0035] Reference Figure 1 The catalytic unit 2 can be disposed within the first receiving cavity 11, located below the first liquid inlet 12 and the gas outlet 14, and above the first liquid outlet 13. The catalytic unit 2 serves to support the catalyst. When the rich liquid to be regenerated flows through the catalytic unit 2, the rich liquid can contact the catalyst, which can lower the activation energy of the carbon dioxide desorption reaction, thereby accelerating the desorption rate. The catalytic unit 2 is detachably disposed within the first receiving cavity 11, facilitating replacement or maintenance of the catalytic unit 2.

[0036] Reference Figure 1 The liquid collecting device 4 can be disposed within the first receiving cavity 11. The liquid collecting device 4 can be located below the catalytic unit 2 and above the first liquid outlet 13. The liquid collecting device 4 can divide the first receiving cavity 11 into a first cavity 111 and a second cavity 112. The first cavity 111 can be located above the liquid collecting device 4, and the second cavity 112 can be located below the liquid collecting device 4.

[0037] Reference Figure 1 The reboiler 5 can be located near the bottom outer side of the tower body 1, and can employ a thermosiphon structure, etc. The reboiler 5 can have a reboiler inlet 51 and a reboiler outlet 52. Liquid can enter the reboiler 5 through the reboiler inlet 51 and exit through the reboiler outlet 52. The tower body 1 can also have a second outlet 15 and a second inlet 16. The second outlet 15 can be located above the liquid collector 4 and communicate with the first chamber 111, while the second inlet 16 can be located below the liquid collector 4 and communicate with the second chamber 112. The reboiler inlet 51 can be connected to the second outlet 15 via a pipe, and the reboiler outlet 52 can be connected to the second inlet 16 via a pipe. Valves (not shown) and electromagnetic flow meters (not shown) can be installed on the pipes for controlling and monitoring the liquid flow rate. The liquid in the first chamber 111 can flow into the reboiler 5 sequentially through the second outlet 15 and the reboiler inlet 51. The liquid can be heated in the reboiler 5 to promote the desorption reaction. The gas-liquid mixture in the reboiler 5 can flow into the second chamber 112 sequentially through the reboiler outlet 52 and the second inlet 16, where gas-liquid separation takes place.

[0038] As an example, compared to the reaction temperature of 120°C in the conventional desorption process, the catalyst in this application can reduce the temperature of the carbon dioxide desorption reaction to 80°C to 100°C, and the reboiler 5 can heat the liquid in the reboiler to 80°C to 100°C. In this embodiment, the liquid temperature at the reboiler outlet 52 can be detected by a temperature sensor (not shown), and the liquid temperature at the reboiler outlet 52 can be maintained within the range of 95±3°C.

[0039] The liquid collecting component 4 may be provided with a venting section 41, the cross-section of which may be circular, polygonal, or other shapes. In this embodiment, the cross-section of the venting section 41 is circular. The venting section 41 may be located near the middle of the liquid collecting component 4, and the first cavity 111 and the second cavity 112 may be connected through the venting section 41. The gas separated in the second cavity 112 may enter the first cavity 111 through the venting section 41 and exit the first cavity 111 through the gas outlet 14. As the gas rises toward the gas outlet 14, it may exchange heat with the liquid to be regenerated, thereby increasing the temperature of the liquid to be regenerated and reducing the heat absorption of the liquid in the reboiler 5, thus reducing the heat load of the reboiler 5. The regenerated liquid can leave the second chamber 112 through the first outlet 13. The liquid to be regenerated in the first chamber 111 will not flow into the second chamber 112 through the vent 41. This allows the regenerated liquid and the liquid to be regenerated to be separated from each other, thereby improving the efficiency of the regenerated liquid in absorbing carbon dioxide in subsequent processes.

[0040] In this application, a catalytic unit 2 is provided below the first liquid inlet 12 and the gas outlet 14. The catalytic unit 2 carries the catalyst, which can reduce the activation energy of the carbon dioxide desorption reaction and accelerate the desorption rate of liquid and carbon dioxide, thereby improving the desorption efficiency of the carbon dioxide desorption tower 100. Compared with traditional desorption towers, the carbon dioxide desorption tower 100 of this application can achieve the same desorption rate at a lower temperature or a shorter residence time. This can reduce the heat load of the reboiler 5, thereby reducing the energy consumption of desorption. At the same time, the carbon dioxide desorption tower 100 achieves rich liquid regeneration at a lower temperature, reducing the thermal degradation of amine solvents, extending the service life of solvents, and reducing solvent replacement and operating costs, thereby reducing the cost of carbon capture. This also allows for a reduction in the height and size of the carbon dioxide desorption tower 100, making it suitable for space-constrained applications such as ships and painting workshops, and reducing equipment investment costs.

[0041] The first receiving chamber 11 is divided into a first chamber 111 and a second chamber 112 by the liquid collecting component 4. The first chamber 111 is located above the liquid collecting component 4 and is used to contain the rich liquid to be regenerated. The second chamber 112 is located below the liquid collecting component 4 and is used to contain the lean liquid after regeneration and the desorbed gas. A circulation loop is formed between the reboiler 5 and the tower body 1. The rich liquid drawn from the first chamber 111 enters the reboiler 5 for heating and regeneration. The gas-liquid mixture after reboiling returns to the second chamber 112 for gas-liquid separation. The venting part 41 provided in the liquid collecting component 4 allows the desorbed gas to rise from the second chamber 112 to the first chamber 111 and transfer mass and heat with the downward rich liquid to increase the temperature of the rich liquid, which can further promote the desorption reaction, thereby further improving the desorption efficiency of the carbon dioxide desorption tower 100 and reducing the energy consumption of desorption.

[0042] In some embodiments, refer to Figure 1 The opening of the venting section 41 facing the catalytic unit 2 can be located above at least a portion of the second liquid outlet 15. Liquid in the first chamber 111 can flow into the reboiler 5 through the second liquid outlet 15, reducing the risk of liquid in the first chamber 111 entering the second chamber 112 through the venting section 41. This reduces the mixing of the liquid to be regenerated with the regenerated liquid and ensures smooth gas flow in the venting section 41, achieving orderly separation of liquid and gas flow within the tower 1 and improving the stability of the desorption process. As an example, the opening of the venting section 41 facing the catalytic unit 2 can be located above the highest point of the second liquid outlet 15 in the height direction Z of the tower 1, further reducing the risk of liquid in the first chamber 111 entering the second chamber 112 through the venting section 41.

[0043] In some embodiments, refer to Figures 1 to 4 The liquid collecting component 4 may include a partition 42. The side of the partition 42 away from the venting section 41 can be connected to the inner wall of the tower body 1. The side of the partition 42 away from the venting section 41 and the inner wall of the tower body 1 can be sealed together by welding or other means. The partition 42 can be an inclined structure, and the partition 42 extends inclinedly from the inner wall of the tower body 1 toward the catalytic unit 2, that is, the partition 42 near the venting section 41 is higher than the partition 42 away from the venting section 41. The partition 42 can enclose the venting section 41, and the venting section 41 can be located in the middle region of the partition 42. The inclined structure of the partition 42 can use gravity to achieve rapid collection and guidance of liquid, and can also prevent liquid in the first chamber 111 from flowing into the second chamber 112 through the venting section 41. At the same time, the enclosed venting section 41 can allow gas in the second chamber 112 to rise smoothly to the first chamber 111.

[0044] In another embodiment, refer to Figures 1 to 4 The liquid collecting component 4 may include a partition 42 and an extension 43 connected to each other. The extension 43 may extend from the partition 42 toward the catalyst unit 2, that is, the extension 43 may extend upward along the height direction Z of the tower body 1. The extension 43 and the partition 42 may together enclose and form a venting section 41. The extension 43 may be located above the partition 42, so that the opening of the venting section 41 toward the catalyst unit 2 may be located above the partition 42, thereby further reducing the risk of liquid in the first chamber 111 entering the second chamber 112 through the venting section 41.

[0045] The partition 42 can be a planar structure or an inclined structure. In this embodiment, the partition 42 can be an inclined structure, and the partition 42 extends inclinedly from the inner wall of the tower body 1 toward the catalytic unit 2, that is, the partition 42 on the side closer to the ventilation section 41 is higher than the partition 42 on the side farther away from the ventilation section 41.

[0046] In some embodiments, refer to Figure 1 The carbon dioxide desorption tower 100 may also include a flow guide 3, which can be disposed within the first receiving cavity 11 and located between the catalytic unit 2 and the liquid collecting unit 4. The flow guide 3 is used to guide the liquid to the liquid collecting unit 4. The flow guide 3 can evenly distribute the liquid flowing down from the catalytic unit 2 onto the liquid collecting unit 4, avoiding channeling or wall flow caused by concentrated liquid flow. This can increase the contact area between the liquid and the gas rising from the second cavity 112, thereby improving the heat exchange efficiency and reducing the heat absorption of the liquid in the reboiler 5, thus reducing the heat load of the reboiler 5.

[0047] In some embodiments, refer to Figures 1 to 4 The flow guide 3 may include a flow guide section 31. The projection of the ventilation section 41 in the height direction Z of the tower body 1 can be located within the range of the projection of the flow guide section 31 in the height direction Z of the tower body 1, that is, the outer diameter of the flow guide section 31 can be larger than the aperture of the ventilation section 41. In this way, the flow guide section 31 can guide the liquid from the catalytic unit 2 to the partition section 42, which can prevent the liquid from falling into the ventilation section 41, thereby preventing the liquid to be regenerated from flowing into the second chamber 112. At the same time, it ensures that the gas desorbed from the reboiler 5 can rise evenly through the ventilation section 41 and fully contact the liquid flowing from top to bottom in the tower body 1, so as to improve the desorption efficiency per unit volume.

[0048] In some embodiments, refer to Figures 1 to 4 The flow guide 31 can be roughly conical in shape, and it can protrude upwards toward the catalytic unit 2. The protruding flow guide 31 can disperse and guide the liquid flowing down from the catalytic unit 2, making the liquid distribution more uniform. There can be a gap between the outer edge of the flow guide 31 and the inner wall of the tower body 1, through which the liquid can flow to the partition section 42.

[0049] The flow guide 3 may further include a flow guide 32, which may be generally conical in shape and located below the flow guide 31. The flow guide 31 and the flow guide 32 may be separate or integrated. The flow guide 32 may protrude towards the liquid collecting member 4, i.e., protrude downwards. The flow guide 32 may be correspondingly arranged with the venting member 41 and located above the venting member 41. The flow guide 32 can disperse and guide the gas rising through the venting member 41, allowing the gas and liquid to fully contact each other, thereby improving the heat exchange efficiency between the gas and liquid.

[0050] The projection of the flow guide 32 in the height direction Z of the tower body 1 can be located within the projection of the flow guide 31 in the height direction Z of the tower body 1. This allows the gas to contact the flow guide 32 first, and then the flow guide 31. The flow guide 31 can guide the gas towards the inner wall of the tower body 1, while also reducing the gas flow velocity, thus further improving the adequacy of gas-liquid contact. In some embodiments, the projection of the flow guide 31 in the height direction Z of the tower body 1 can be located within the projection of the flow guide 32 in the height direction Z of the tower body 1, or the projections of the flow guide 31 and the flow guide 32 in the height direction Z of the tower body 1 can completely coincide.

[0051] In some embodiments, refer to Figure 1 The flow guide 3 may also include a support 33, such as a stainless steel support rod. Multiple support 33s may be evenly distributed along the circumference of the tower body 1. One end of the support 33 can be connected to the flow guide 31 via welding or other methods. The other end of the support 33 can be connected to the inner wall of the tower body 1 via welding or other methods. The support 33 provides stable support for the flow guide 3, ensuring its installation stability within the tower body 1, withstanding the continuous impact of liquid flow, and preventing displacement or deformation of the flow guide 3. This improves the long-term stability of the flow guide effect and extends the service life of the equipment.

[0052] In some embodiments, refer to Figure 1 The catalytic unit 2 may include a packing layer 21 and a receiving chamber 22. The packing layer 21 is used to support a first catalyst, and the receiving chamber 22 is used to support a second catalyst. The packing layer 21 may be one or more layers, and the receiving chamber 22 may also be one or more layers. When the packing layer 21 and the receiving chamber 22 are multiple layers, they may be stacked in a staggered manner, or multiple layers of packing layer 21 may all be located on top of multiple layers of receiving chamber 22. The number of layers and the stacking method of the packing layer 21 and the receiving chamber 22 can be set as needed.

[0053] As an example, both the packing layer 21 and the receiving chamber 22 can be a single layer, with the packing layer 21 positioned above the receiving chamber 22. Under gravity, the rich liquor first flows through the packing layer 21, contacting the first catalyst and undergoing primary catalytic desorption; subsequently, it flows into the receiving chamber 22, contacting the second catalyst and undergoing secondary catalytic desorption. This secondary catalytic design of the packing layer 21 and the receiving chamber 22 achieves staged catalytic desorption of the rich liquor, reducing the activation energy of the carbon dioxide desorption reaction, accelerating the desorption rate, increasing the desorption efficiency per unit volume, and achieving the desired desorption effect at a lower temperature or shorter residence time.

[0054] In some embodiments, the first catalyst and the second catalyst may be of the same type or different types. Catalyst types include, for example, metal oxides / hydroxyoxides, modified zeolites / molecular sieves, metal-supported carbon materials, and solid acid treatment waste. Metal oxides / hydroxyoxides include, for example, MnOOH / HZSM-5 composite catalysts, TiO2 (titanium dioxide) and V2O5 (vanadium pentoxide), and CeO2 (cerium dioxide) coated catalysts. Modified zeolites / molecular sieves include, for example, M-montmorillonite (M=Cr, Fe, Co). Metal-supported carbon materials include, for example, metal (such as Fe, Ni, Mo, etc.) impregnated activated carbon. Solid acid treatment waste includes, for example, acid-treated fly ash.

[0055] In some embodiments, the first catalyst can be coated onto the packing layer 21. Coating the packing layer 21 with the first catalyst can significantly increase the contact area between the catalyst and the rich liquid, achieving efficient first-stage catalytic desorption. The second catalyst can be a particulate catalyst, which can be filled into the receiving chamber 22 to achieve second-stage catalytic desorption of the rich liquid. The two stages of catalysis can be performed using the same or different types of catalysts according to actual desorption requirements, thereby improving the flexibility and adaptability of catalytic desorption and adapting to different treatment needs for exhaust gases containing different concentrations of carbon dioxide.

[0056] As an example, packing layer 21 may be a perforated metal plate corrugated packing, which can be an industrial packing assembled by punching holes in the surface of a thin metal sheet, rolling small and large corrugations. The aperture of the openings in packing layer 21 may be, for example, 1 mm to 2.5 mm, and the specific surface area of ​​packing layer 21 may be 250 m². 2 / m 3 up to 450m 2 / m 3 The specific surface area of ​​the packing layer 21 can be 250 m². 2 / m 3 280m 2 / m 3 310m 2 / m 3 340m 2 / m 3 370m 2 / m 3 400m 2 / m 3 4300m 2 / m 3 450m 2 / m 3 Any value in the range, or any value between the two.

[0057] The receiving container 22 is, for example, a container with a porous structure. The diameter of the openings in the receiving container 22 is, for example, 1 mm to 2.5 mm, and the porosity of the receiving container 22 can be, for example, 40% to 50%. The porosity of the receiving container 22 can be any value from 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, or any value between two of these. The receiving container 22 is internally loaded with particulate second catalyst, the particle size of which is, for example, 3 mm to 5 mm.

[0058] Both the packing layer 21 and the receiving chamber 22 are porous structures, and gaps also exist between the particulate second catalyst particles. This allows gas to rise and liquid to fall, while also enabling the redistribution of gas and liquid. This not only increases the contact area between gas and liquid but also extends the contact time, allowing the liquid to remain in the catalytic unit 2 for 1 to 3 minutes, thereby improving the catalytic desorption efficiency. Furthermore, the liquid to be regenerated can form a liquid film on the packing layer 21 and the receiving chamber 22, for example, within the openings in the packing layer 21 and the receiving chamber 22, allowing for sufficient contact with the rising gas.

[0059] In some embodiments, refer to Figure 1 The carbon dioxide desorption tower 100 may also include a steam generator 6, which can be connected to the reboiler 5 and is used to provide a heat source for the reboiler 5. As an example, the steam generator 6 can utilize the waste heat of the ship's engine to generate medium- and low-pressure steam, and transfer the latent heat of condensation of the steam to the liquid to be regenerated in the reboiler 5, providing a stable, controllable and continuous energy input for the boiling regeneration of the liquid.

[0060] The carbon dioxide desorption tower 100 of this application can be modified based on the existing desorption tower. Performance improvement can be achieved simply by replacing or adding the catalytic unit 2, the liquid collection unit 4 and the flow guiding unit 3. There is no need for large-scale reconstruction of the existing carbon capture system. It is easy to implement and has low modification cost. It can provide an economical and efficient solution for upgrading the existing carbon capture system, reducing equipment investment costs and technical upgrade thresholds.

[0061] According to a second aspect of this application, one embodiment of this application provides a carbon dioxide desorption method using a carbon dioxide desorption tower 100 as described above. The carbon dioxide desorption method includes the following steps.

[0062] The liquid enters the first chamber 111 through the first inlet 12, flows through the catalytic unit 2 and the liquid collection unit 4 in sequence, and enters the reboiler 5 for regeneration.

[0063] Specifically, the rich liquid to be regenerated enters the first chamber 111 through the first inlet 12. Under gravity, the rich liquid flows downwards, sequentially passing through the packing layer 21, the receiving chamber 22, and the guide element 3 of the catalytic unit 2. In the packing layer 21, the rich liquid comes into contact with the first catalyst coated on the packing surface, undergoing a primary catalytic desorption reaction, releasing some carbon dioxide. The rich liquid flowing out of the packing layer 21 continues downwards into the receiving chamber 22, where it comes into full contact with the granular second catalyst loaded inside, undergoing a secondary catalytic desorption reaction, further releasing carbon dioxide. The rich liquid flowing out of the receiving chamber 22 enters the guide element 3, and after being evenly distributed by the guide element 3, flows to the collecting element 4. The rich liquid collects on the collecting element 4 and accumulates at the bottom of the first chamber 111, flowing into the reboiler 5 through the second outlet 15 and the reboiler inlet 51. In the reboiler 5, it is heated to 95±3℃, undergoing a vigorous desorption reaction, releasing a large amount of carbon dioxide.

[0064] The heat source for reboiler 5 is provided by steam generator 6. Steam generator 6 can use the waste heat of the ship's engine to generate steam, and transfer the latent heat of condensation of the steam to the rich liquid in reboiler 5, thereby achieving efficient energy utilization.

[0065] The regenerated gas-liquid mixture enters the second chamber 112. The desorbed gas rises through the vent 41 and flows out through the vent 14. The regenerated liquid flows out through the first liquid outlet 13.

[0066] Specifically, the gas-liquid mixture undergoes gas-liquid separation in the second chamber 112. The desorbed carbon dioxide gas rises to the first chamber 111 through the vent 41 of the liquid collecting element 4, where it undergoes mass and heat transfer with the descending rich liquid, promoting the desorption of carbon dioxide from the rich liquid. The regenerated lean liquid accumulates at the bottom of the second chamber 112. The lean liquid can be discharged from the tower 1 through the first liquid outlet 13, and the carbon dioxide gas can be discharged from the tower 1 through the gas outlet 14. After condensation and dehydration, a high-purity carbon dioxide product is obtained.

[0067] According to the third aspect of this application, referring to Figure 5One embodiment of this application provides a decarbonization system, which may include a carbon dioxide absorption tower 200 and a carbon dioxide desorption tower 100 as described above. The carbon dioxide absorption tower 200 may have a cylindrical structure, etc., with an inner diameter of, for example, 1.5m, and a height of, for example, 8m. The carbon dioxide absorption tower 200 may have a third liquid inlet 210 and a third liquid outlet 220. The third liquid inlet 210 may be located at the upper part or top of the carbon dioxide absorption tower 200, and the third liquid outlet 220 may be located at the lower part or bottom of the carbon dioxide absorption tower 200. The carbon dioxide absorption tower 200 may also have a flue gas inlet 230 and a flue gas outlet 240. The flue gas inlet 230 may be located at the lower part or bottom of the carbon dioxide absorption tower 200, and the flue gas outlet 240 may be located at the upper part or top of the carbon dioxide absorption tower 200. The third inlet 210 can be connected to the first outlet 13, allowing the lean liquid in the second chamber 112 of the carbon dioxide desorption tower 100 to be sequentially transported to the carbon dioxide absorption tower 200 through the first outlet 13 and the third inlet 210. The third outlet 220 can be connected to the first inlet 12, allowing the rich liquid after carbon dioxide absorption to be sequentially transported to the carbon dioxide desorption tower 100 through the third outlet 220 and the first inlet 12. The third inlet 210 can be connected to the first outlet 13 of the carbon dioxide desorption tower 100 via a pipeline, and the third outlet 220 can be connected to the first inlet 12 of the carbon dioxide desorption tower 100 via a pipeline, forming a circulation loop of lean and rich liquids.

[0068] The decarbonization system may further include a heat exchanger 300, which may be disposed between the carbon dioxide absorption tower 200 and the carbon dioxide desorption tower 100. The heat exchanger 300 may have a first heat exchange channel (not shown) and a second heat exchange channel (not shown). The inlet of the first heat exchange channel is connected to the first liquid outlet 13 of the carbon dioxide desorption tower 100, and the outlet of the first heat exchange channel is connected to the third liquid inlet 210 of the carbon dioxide absorption tower 200. The inlet of the second heat exchange channel is connected to the third liquid outlet 220 of the carbon dioxide absorption tower 200, and the outlet of the second heat exchange channel is connected to the first liquid inlet 12 of the carbon dioxide desorption tower 100. As an example, the heat exchanger 300 is, for example, a shell-and-tube heat exchanger, in which the shell side is fed with the high-temperature lean liquid flowing out of the first outlet 13 of the carbon dioxide desorption tower 100, and the tube side is fed with the low-temperature rich liquid flowing out of the third outlet 220 of the carbon dioxide absorption tower 200. The lean liquid and the rich liquid exchange heat in the heat exchanger 300, the rich liquid is heated and the lean liquid is cooled, realizing the recovery and utilization of heat, thereby reducing the heat load of the reboiler 5.

[0069] In this application, by incorporating a heat exchanger 300, the decarbonization system achieves energy recovery and utilization, thereby reducing the system's energy consumption. Simultaneously, the two-stage catalytic desorption structure and fluid distribution structure within the carbon dioxide desorption tower 100 further improve desorption efficiency, making the entire system more efficient and energy-saving.

[0070] Through the synergistic design of the carbon dioxide absorption tower 200 and the desorption tower, a low-energy-consumption, high-recycling carbon capture closed loop is formed. The countercurrent absorption design of the carbon dioxide absorption tower 200 and the high-efficiency catalytic desorption design of the carbon dioxide desorption tower 100 are combined to achieve efficient absorption and desorption of carbon dioxide. The desorbed carbon dioxide gas can be condensed and dehydrated to obtain high-purity carbon dioxide products, which can be directly used in food processing, chemical synthesis, geological storage, and other fields, realizing the resource utilization of carbon dioxide and improving the economic and environmental benefits of the project.

[0071] As an example, the decarbonization system works as follows.

[0072] Carbon dioxide-containing flue gas enters the carbon dioxide absorption tower 200 through flue gas inlet 230 and flows upward. Lean liquor (the liquid after regeneration in the carbon dioxide desorption tower 100) enters the carbon dioxide absorption tower 200 through the third inlet 210 and is sprayed downward. The lean liquor and flue gas come into countercurrent contact within the carbon dioxide absorption tower 200; the lean liquor absorbs carbon dioxide from the flue gas, generating rich liquor. The purified flue gas exits through flue gas outlet 240. The rich liquor flows out through the third outlet 220 and enters the second heat exchange channel of the heat exchanger 300.

[0073] Simultaneously, the high-temperature lean solution flowing from the first outlet 13 of the carbon dioxide desorption tower 100 enters the first heat exchange channel of the heat exchanger 300. In the heat exchanger 300, the high-temperature lean solution exchanges heat with the low-temperature rich solution, cooling the high-temperature lean solution and preheating the low-temperature rich solution. The preheated rich solution flows out from the outlet of the second heat exchange channel of the heat exchanger 300 and enters the first inlet 12 of the carbon dioxide desorption tower 100 for regeneration. The cooled lean solution flows out from the outlet of the first heat exchange channel of the heat exchanger 300 and returns to the third inlet 210 of the carbon dioxide absorption tower 200 for recycling.

[0074] The carbon dioxide desorption tower 100 regenerates the rich liquid to generate lean liquid and carbon dioxide gas. Its specific working process has been described in detail in the examples and will not be repeated here.

[0075] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0076] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0077] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0078] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A carbon dioxide desorption tower, characterized in that, include: The tower body has a first receiving cavity and a first liquid inlet, a first liquid outlet and a gas outlet communicating with the first receiving cavity; A catalytic unit is located below the first liquid inlet and the gas outlet, and the catalytic unit is used to carry the catalyst; A liquid collecting device is located below the catalytic unit and above the first liquid outlet, and the liquid collecting device divides the first receiving cavity into a first cavity and a second cavity; A reboiler having a reboiler inlet and a reboiler outlet, and a tower having a second outlet and a second inlet. Liquid in the first chamber flows into the reboiler sequentially through the second outlet and the reboiler inlet, and liquid in the reboiler flows into the second chamber sequentially through the reboiler outlet and the second inlet. The liquid collecting component is provided with a venting section, and the first cavity and the second cavity are connected through the venting section.

2. The carbon dioxide desorption column according to claim 1, characterized by The opening of the venting section facing the catalytic unit is located above at least a portion of the second liquid outlet.

3. The carbon dioxide desorption column of claim 1, wherein, The liquid collecting component includes a partition, and the side of the partition away from the vent is connected to the inner wall of the tower body; The partition is an inclined structure, and extends inclinedly from the inner wall of the tower towards the catalytic unit, forming the ventilation section.

4. The carbon dioxide desorption column of claim 1, wherein, The liquid collection component includes a partition and an extension that are connected to each other. The extension extends from the partition toward the catalytic unit, and the extension and the partition together enclose the ventilation section.

5. The carbon dioxide desorption column of claim 1, wherein, The carbon dioxide desorption tower also includes a flow guide, which is located between the catalytic unit and the liquid collection unit, and is used to guide liquid to the liquid collection unit.

6. The carbon dioxide desorption column of claim 5, wherein, The flow guide includes a flow guide section, and the projection of the ventilation section in the height direction of the tower body is located within the range of the projection of the flow guide section in the height direction of the tower body.

7. The carbon dioxide desorption column of claim 6, wherein, The drainage portion is provided to protrude toward the catalytic unit; and / or The drainage component further includes a flow guide portion, which is located below the drainage component and protrudes towards the liquid collection component.

8. The carbon dioxide desorption column of claim 6, wherein, The flow guide also includes a support part, one end of which is connected to the flow guide part, and the other end of which is connected to the inner wall of the tower body.

9. The carbon dioxide desorption column of claim 1, wherein, The catalytic unit includes a packing layer and a receiving chamber, wherein the packing layer is used to support a first catalyst and the receiving chamber is used to support a second catalyst.

10. The carbon dioxide desorption tower according to claim 9, characterized in that, The filler layer is located above the receiving chamber.

11. The carbon dioxide desorption tower according to claim 9, characterized in that, The first catalyst and the second catalyst may be of the same type or different types. Wherein, the first catalyst is coated on the filler layer; and / or, The second catalyst is a particulate catalyst.

12. The carbon dioxide desorption column of claim 1, wherein, The carbon dioxide desorption tower also includes a steam generator connected to the reboiler, which provides a heat source for the reboiler.

13. A method of desorbing carbon dioxide, characterized by, Using the carbon dioxide desorption tower as described in any one of claims 1 to 12, the carbon dioxide desorption method comprises: The liquid enters the first cavity through the first inlet, flows sequentially through the catalytic unit and the liquid collection device, and then enters the reboiler for regeneration; The regenerated gas-liquid mixture enters the second chamber, the desorbed gas rises through the vent and flows out through the outlet, and the regenerated liquid flows out through the first liquid outlet.

14. A decarboxylation system characterized by, The invention includes a carbon dioxide absorption tower and a carbon dioxide desorption tower as described in any one of claims 1 to 12, wherein the carbon dioxide absorption tower has a third inlet and a third outlet, the third inlet being connected to the first outlet and the third outlet being connected to the first inlet.

Images