A system suitable for flue gas dehydration, carbon dioxide capture

Abstract

This application discloses a system for dehydrating and capturing carbon dioxide from flue gas, belonging to the fields of flue gas treatment and adsorption / absorption technology. The system includes a diversion valve, a heat exchanger, a regenerative regeneration wheel, a hollow dehydration assembly, a gas-liquid separator, a booster pump, a carbon dioxide adsorption device, and a carbon dioxide storage tank. After diversion, the flue gas flows in two streams: one stream enters the regenerative regeneration wheel for adsorption and dehydration, while the other stream passes through the heat exchanger and then enters the regenerative regeneration wheel for regeneration. The treated flue gas then sequentially passes through the hollow dehydration assembly, the gas-liquid separator, and the booster pump before entering the carbon dioxide adsorption device. The captured carbon dioxide is stored in the carbon dioxide storage tank. This system can be used for moisture removal and carbon dioxide capture from flue gas.

Description

Technical Field

[0001] This application belongs to the field of exhaust gas treatment and adsorption / absorption technology, and relates to a system suitable for dehydration and carbon dioxide capture of flue gas. Background Technology

[0002] Post-combustion capture technology, due to its minimal impact on existing production processes, has been used for carbon dioxide treatment in power plant flue gas and can be extended to tail gas treatment scenarios in industries such as cement and steel. The low concentration and partial pressure of carbon dioxide in flue gas reduce physical adsorption or absorption efficiency, while water vapor in the flue gas further affects carbon dioxide capture. Currently, carbon dioxide capture in coal-fired power plants mainly employs absorption methods. While this method achieves capture, its regeneration energy consumption is high. In contrast, adsorption methods have the advantage of lower regeneration energy consumption. Therefore, it is necessary to construct a suitable tail gas treatment system around the adsorption materials and treatment pathways. Existing solutions lack a complete structure that can simultaneously address flue gas dehydration and carbon dioxide adsorption and capture, especially lacking a system configuration that first reduces the moisture content of the flue gas through a cyclic treatment path before improving carbon dioxide adsorption efficiency. This makes it difficult to simultaneously improve moisture removal efficiency and subsequent capture efficiency. Summary of the Invention

[0003] The purpose of this application is to solve the technical problems of existing flue gas where water vapor affects carbon dioxide capture efficiency and the lack of a recycling system that takes into account both dehydration and carbon dioxide adsorption, and to provide a system suitable for flue gas dehydration and carbon dioxide capture.

[0004] To achieve the above objectives, this application adopts the following technical solution: In a first aspect, this application provides a system suitable for flue gas dehydration and carbon dioxide capture, comprising a diversion valve, a heat exchanger, a regenerative regeneration wheel, a hollow dehydration assembly, a gas-liquid separator, a booster pump, a carbon dioxide adsorption device, and a carbon dioxide storage tank; the diversion valve is connected to the air inlet of the regenerative regeneration wheel and the air inlet of the heat exchanger respectively; the heat exchanger is connected to the air inlet of the regenerative regeneration wheel; the regenerative regeneration wheel includes a rotating wheel, and an adsorbate filling area is provided inside the rotating wheel; the regenerative regeneration wheel is connected to the air inlet of the gas-liquid separator through the hollow dehydration assembly; the air outlet of the gas-liquid separator is connected to the air inlet of the carbon dioxide adsorption device through the booster pump; the carbon dioxide adsorption device is connected to the carbon dioxide storage tank to store carbon dioxide.

[0005] Furthermore, the diversion valve of this application has a first outlet, a second outlet, and an inlet for communicating with the flue gas pipeline to be treated. The first outlet is connected to the air inlet pipe of the heat storage regeneration wheel, the second outlet is connected to the inlet of the heat exchanger, and the outlet of the heat exchanger is connected to the air inlet pipe of the heat storage regeneration wheel.

[0006] Furthermore, the heat storage and regeneration wheel of this application also includes an air inlet pipe, an air outlet pipe, and a sealing layer. The air inlet pipe and the air outlet pipe are respectively disposed on both sides of the rotating wheel, and the sealing layer is disposed on the outer periphery of the rotating wheel.

[0007] Furthermore, the adsorbate filling region of this application is filled with a metal-organic framework material.

[0008] Furthermore, the hollow dehydration assembly of this application includes a housing and a dehydration core disposed within the housing.

[0009] Furthermore, the dehydration core of this application is a hollow structure having multiple through cavities extending along the axial direction.

[0010] Furthermore, the main material of the dehydration core of this application includes a metal-organic framework material and a template material, wherein the molecular chain of the template material has both hydrophilic and hydrophobic groups.

[0011] Furthermore, the metal-organic framework material of this application is MOF-808, and the template material is poly(N-isopropylacrylamide).

[0012] Furthermore, the dehydration core of this application is subjected to salting treatment, and the salts used in the salting treatment include calcium chloride.

[0013] Furthermore, the carbon dioxide adsorption device of this application includes a high-temperature flue gas inlet pipe, a regeneration zone, a carbon dioxide outlet, a low-temperature and low-humidity flue gas inlet pipe, and an adsorption zone. The low-temperature and low-humidity flue gas inlet pipe is connected to the adsorption zone, the high-temperature flue gas inlet pipe is connected to the regeneration zone, and the carbon dioxide outlet is connected to the regeneration zone. The low-temperature and low-humidity flue gas inlet pipe is connected to the outlet of the gas-water separator through the booster pump.

[0014] Compared with the prior art, this application has the following beneficial effects: This application achieves efficient removal of moisture from flue gas by combining a regenerative regeneration wheel and a hollow dehydration assembly. The rotating wheel and adsorbent filling zone in the regenerative regeneration wheel effectively adsorb moisture, and the hollow dehydration assembly further removes moisture from the flue gas, thereby improving dehydration efficiency. The carbon dioxide adsorption device in the system uses highly efficient adsorption materials such as metal-organic frameworks to improve carbon dioxide capture efficiency while removing moisture, reducing the impact of water vapor on carbon dioxide capture and ensuring efficient carbon dioxide capture. Through a reasonable flow path design, equipped with a diversion valve and a gas-liquid separator, the system achieves recycling during the treatment process. The diversion valve distributes the flue gas to different treatment units, allowing the flue gas to undergo dehydration and capture multiple times, improving treatment efficiency. After capture, the carbon dioxide is transported to a carbon dioxide storage tank via a booster pump, not only efficiently storing the captured carbon dioxide but also facilitating subsequent utilization. Furthermore, the system fully considers efficient energy utilization; the heat exchanger uses the heat of the flue gas to preheat the treated flue gas, reducing energy consumption during the regeneration process of the regenerative regeneration wheel and lowering overall energy consumption. Overall, the system has achieved optimizations in dehydration, carbon dioxide capture, and energy consumption, which not only improves treatment efficiency but also provides good environmental protection and economic benefits. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a flowchart illustrating the process of treating moisture and carbon dioxide in flue gas in this application.

[0017] Figure 2 This is a schematic diagram of the heat storage and regeneration wheel structure of this application.

[0018] Figure 3 This is a schematic diagram of the hollow dehydration component structure of this application.

[0019] Figure 4 This is a schematic diagram of the carbon dioxide adsorption device of this application.

[0020] Among them, 1-heat exchanger, 2-hollow dehydration component, 3-gas-water separator, 9-heat storage regeneration wheel, 5-booster pump, 6-carbon dioxide storage tank, 7-carbon dioxide adsorption device, 8-desulfurization and denitrification device, 10-flow meter, 4-diverter valve, 91-adsorbent filling area, 92-outlet pipe, 93-sealing layer, 94-inlet pipe, 95-rotating wheel, 22-dehydration core, 21-outer shell, 71-high temperature flue gas inlet pipe, 72-regeneration zone, 73-carbon dioxide outlet, 74-low temperature and low humidity flue gas inlet pipe, 75-adsorption zone. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, 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. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] In the description of the embodiments of this application, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0026] In the description of the embodiments of this application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0027] The present application will now be described in further detail with reference to the accompanying drawings: See Figure 1 This application discloses a system suitable for dehydration and carbon dioxide capture of flue gas. The system includes a diversion valve 4, a heat exchanger 1, a regenerative regeneration wheel 9, a hollow dehydration assembly 2, a gas-water separator 3, a booster pump 5, a carbon dioxide adsorption device 7, and a carbon dioxide storage tank 6.

[0028] After entering the diversion valve 4, the flue gas to be treated is distributed to different processing paths. The diversion valve 4 is connected to the inlet of the regenerative regeneration wheel 9 and the inlet of the heat exchanger 1, respectively. The outlet of the heat exchanger 1 is further connected to the inlet of the regenerative regeneration wheel 9, thereby allowing the flue gas to enter the regenerative regeneration wheel 9 at different temperatures and humidity levels. The regenerative regeneration wheel 9 is equipped with a rotating wheel 95, and an adsorbent filling zone 91 is formed inside the rotating wheel 95. The flue gas undergoes dehydration treatment when passing through the adsorbent filling zone 91. Downstream of the regenerative regeneration wheel 9, it is connected to the inlet of the gas-liquid separator 3 via a hollow dehydration assembly 2. The hollow dehydration assembly 2 is used to further remove moisture from the flue gas output from the regenerative regeneration wheel 9, and the gas-liquid separator 3 is used to separate the gas and liquid phases after treatment.

[0029] The gas separated by the gas-water separator 3 is output from its outlet and transported to the carbon dioxide adsorption device 7 by the booster pump 5. The carbon dioxide adsorption device 7 enriches and captures carbon dioxide in the dehumidified flue gas, and the captured carbon dioxide is further introduced into the carbon dioxide storage tank 6 for storage.

[0030] With the above structural configuration, before entering the carbon dioxide adsorption device 7, the flue gas undergoes synergistic treatment by the regenerative heat storage wheel 9 and the hollow dehydration component 2, which reduces the moisture content in the flue gas and weakens the interference of water vapor on the subsequent carbon dioxide adsorption process. At the same time, the heat exchanger 1 and the diversion valve 4 work together to form a circulating treatment path, which is beneficial to take into account both dehydration and subsequent carbon dioxide capture processes. This addresses the technical problems of existing flue gas water vapor affecting carbon dioxide capture efficiency and the lack of a circulating treatment system that takes into account both dehydration and carbon dioxide adsorption, thereby improving the overall treatment efficiency.

[0031] In one complete embodiment of this application, the entire system can be constructed around a processing chain of "front-end diversion—regeneration wheel dehydration—hollow core deep dehydration—gas-liquid separation—pressurized conveying—carbon dioxide adsorption and regeneration—high-concentration carbon dioxide storage". The system can be used for power plant flue gas treatment, and can also be extended to tail gas treatment scenarios in cement, steel and other industries as needed.

[0032] like Figure 1 As shown, the main body of the system includes a heat exchanger 1, a hollow dehydration assembly 2, a gas-liquid separator 3, a diversion valve 4, a booster pump 5, a carbon dioxide storage tank 6, a carbon dioxide adsorption device 7, and a regenerative regeneration wheel 9. In some embodiments, a desulfurization and denitrification device 8 may also be installed at the front end of the system for conventional purification of the flue gas; a flow meter 10 may also be installed to monitor the flow rate of the flue gas entering the system, so as to adjust the speed of the subsequent regeneration wheel, the diversion ratio, and the amount of adsorbate loaded. The desulfurization and denitrification device 8 and the flow meter 10 are not the only necessary structures to realize the system of this application, but placing them at the front end is beneficial to improving the state of the flue gas entering the dehydration and collection stage and improving the stability of the entire system operation.

[0033] In this embodiment, the flue gas to be treated enters the diversion valve 4 after being purified at the front end. The diversion valve 4 has an inlet, a first outlet, and a second outlet. The inlet is connected to the flue gas pipeline to be treated, the first outlet is connected to the inlet pipe 94 of the regenerative regeneration wheel 9, and the second outlet is connected to the inlet of the heat exchanger 1. The outlet of the heat exchanger 1 is further connected to the inlet pipe 94 of the regenerative regeneration wheel 9. Through this arrangement, the diversion valve 4 divides the flue gas into two streams: one stream of flue gas can be directly sent to the regenerative regeneration wheel 9 as low-temperature, high-humidity treated flue gas; the other stream of flue gas first enters the heat exchanger 1 to be heated, and then is sent to the regenerative regeneration wheel 9 as regeneration flue gas. The heat exchanger 1 can use the sensible heat of the untreated high-temperature flue gas to heat the diverted flue gas to form high-temperature, low-humidity regeneration flue gas, thereby reducing the additional energy consumption of the subsequent regeneration process.

[0034] like Figure 2 As shown, the regenerative regeneration wheel 9 includes an adsorbent filling area 91, an outlet pipe 92, a sealing layer 93, an inlet pipe 94, and a rotating wheel 95. The inlet pipe 94 and outlet pipe 92 are respectively located on both sides of the rotating wheel 95, allowing flue gas to pass through the adsorbent filling area 91 inside the rotating wheel 95 for treatment. The sealing layer 93 is located on the outer periphery of the rotating wheel 95 to reduce cross-contamination and heat loss between different treatment areas, improving the gas path stability during wheel operation. The rotating wheel 95 can be driven to rotate continuously or intermittently by a drive mechanism. As the rotating wheel 95 rotates, the adsorbent filling areas 91 located in different circumferential regions can sequentially receive treated flue gas and regenerated flue gas, thus forming a cyclical switching between adsorption and regeneration stations on the same wheel.

[0035] The adsorbate filling zone 91 is filled with a metal-organic framework (MOF) material. Preferably, MOF-808 can be used; in other embodiments, other MOF materials suitable for flue gas dehydration can also be used. Using this type of material is advantageous in two ways: firstly, it allows for selective adsorption of water vapor using its pore structure and adsorption sites; secondly, it facilitates faster regeneration at lower regeneration temperatures. To adapt to different operating conditions, the rotational speed of the rotating wheel 95 can be adjusted according to the inlet air velocity, and the adsorbate filling ratio can also be configured according to the flue gas flow rate and flue gas component content. Through coordinated adjustment of rotational speed and filling amount, processing capacity, adsorption sufficiency, and regeneration efficiency can be balanced.

[0036] During operation, the low-temperature, high-humidity flue gas from the first outlet of the diversion valve 4 enters the adsorption station corresponding to the rotating wheel 95 through the inlet pipe 94. Water vapor in the flue gas is adsorbed by the adsorbent filling area 91, resulting in low-temperature, low-humidity flue gas, which is then discharged through the outlet pipe 92. The high-temperature, low-humidity regeneration flue gas from the heat exchanger 1 enters the regeneration station corresponding to the rotating wheel 95, heating the adsorbent filling area 91 that has already adsorbed moisture, causing the adsorbed moisture to desorb and form low-temperature, high-humidity regeneration tail gas, which is then discharged through the outlet pipe 92. Because the treated flue gas path and the regeneration flue gas path are alternately distributed within the wheel body, the system can continuously achieve cyclic switching between adsorption and regeneration. After multiple cycles, the metal-organic framework material can still maintain good framework stability, thus making it suitable for repeated operation under wet flue gas conditions.

[0037] In some embodiments of this application, the intake pipe 94 can correspond to the same physical channel for connecting flue gas under different operating conditions at different times, or it can be divided into a treatment flue gas branch and a regeneration flue gas branch according to the specific equipment layout. As long as the treatment flue gas can enter the adsorption station and the regeneration flue gas can enter the regeneration station, it can fall within the scope of this application.

[0038] The low-temperature, high-humidity regeneration exhaust gas from the regenerative regeneration wheel 9 can further enter the hollow dehydration assembly 2 for deep dehydration treatment. For example... Figure 3 As shown, the hollow dehydration assembly 2 includes a housing 21 and a dehydration core 22 disposed within the housing 21. The dehydration core 22 is a hollow structure with multiple through cavities extending axially. The multiple through cavities extending along the length of the dehydration core 22 allow it to form a structure similar to a series of porous channels, which helps to expand the gas-material contact interface and provides flow space for liquid water discharge. In some embodiments, to improve the internal gas path sealing of the hollow dehydration assembly 2, an additional sealing structure can be provided between the housing 21 and the dehydration core 22 to reduce bypass leakage.

[0039] The main materials of the dehydration core 22 include a metal-organic framework (MOF) material and a template material. The template material's molecular chain simultaneously possesses hydrophilic and hydrophobic groups. Preferably, the MOF material can be MOF-808, and the template material can be poly(N-isopropylacrylamide). This template material exhibits phase transition response characteristics; after endothermic heating to a certain temperature, it undergoes volume shrinkage, causing a reversible change in the hydrophilic / hydrophobic state of the material surface. Based on this characteristic, the dehydration core 22 can enhance water vapor capture under high humidity conditions and promote liquid water desorption or shedding after changes in conditions. The dehydration core 22 can be prepared by freeze-drying using a template method, forming a relatively stable composite structure between the template material and the MOF material.

[0040] To further improve dehydration efficiency, the dehydration core 22 can also be subjected to salting treatment. Salts used for salting treatment may include calcium chloride. The role of the metal-organic framework material in this composite structure is mainly reflected in providing additional adsorption sites for the polymer system and increasing the contact area with water vapor; after the introduction of salts such as calcium chloride, highly hydrophilic water-active sites can be formed in the material through ion grafting, thereby improving water vapor adsorption performance. Taking poly(N-isopropylacrylamide) as an example, the interaction between its molecular chain and calcium ions helps to enhance its affinity for water vapor.

[0041] During operation, the low-temperature, high-humidity regeneration exhaust gas comes into contact with the dehydration core 22. The moisture in the flue gas is further enriched and converted into liquid water under the influence of the material system of the dehydration core 22. To improve the efficiency of liquid water removal from the surface of the dehydration core 22, low-temperature, low-humidity flue gas can be selectively introduced to flow along the through-cavity in the middle of the dehydration core 22, creating a scavenging effect on the droplets and promoting the removal of liquid water from the surface or channels of the dehydration core 22. Because the dehydration core 22 adopts a hollow structure with multiple through-cavities, its cross-section can form a channel layout similar to a lotus root, thereby increasing the mass transfer area and facilitating simultaneous contact of moisture, liquid water precipitation, and droplet removal. The dehydrated mixture then enters the gas-liquid separator 3, where the liquid water is separated from the treated gas.

[0042] In some embodiments of this application, to further reduce the moisture content of the flue gas, the low-temperature, low-humidity flue gas separated by the gas-water separator 3 can re-enter the subsequent first-stage regenerative regeneration wheel 9 for secondary treatment, forming a multi-stage series dehydration path; correspondingly, the low-temperature, high-humidity regeneration tail gas discharged from the subsequent first-stage regenerative regeneration wheel 9 can also re-enter the hollow dehydration assembly 2 for treatment. A multi-stage dehydration structure is not a mandatory limitation in all embodiments, but when the inlet flue gas humidity is high or the subsequent carbon dioxide adsorption has strict humidity requirements, using a two-stage or multi-stage regenerative regeneration wheel series arrangement is beneficial for further reducing the moisture content entering the carbon dioxide adsorption device 7.

[0043] The gas separated by the gas-water separator 3 is output from its outlet and sent to the carbon dioxide adsorption unit 7 via the booster pump 5. The booster pump 5 can be used to overcome the flow resistance in the subsequent adsorption unit, so that the treated low-temperature and low-humidity flue gas enters the carbon dioxide adsorption unit 7 at a more suitable pressure and flow rate, thereby providing stable inlet conditions for carbon dioxide adsorption.

[0044] like Figure 4 As shown, the carbon dioxide adsorption device 7 includes a high-temperature flue gas inlet pipe 71, a regeneration zone 72, a carbon dioxide outlet 73, a low-temperature, low-humidity flue gas inlet pipe 74, and an adsorption zone 75. The low-temperature, low-humidity flue gas inlet pipe 74 is connected to the adsorption zone 75, through which the low-temperature, low-humidity flue gas from the booster pump 5 enters the adsorption zone 75. Since the flue gas has been dehydrated in the preceding path, the water vapor content in the flue gas entering the adsorption zone 75 is low, thus reducing the competition of water vapor for carbon dioxide adsorption sites and allowing more effective sites to be occupied for carbon dioxide capture. The adsorption zone 75 can be filled with a metal-organic framework material with a high carbon dioxide adsorption capacity, preferably modified UiO-66, MOF-808, etc. The adsorption material in the regeneration zone 72 can be the same as that in the adsorption zone 75, so that the same adsorption medium can be used for recycling in the adsorption and regeneration processes.

[0045] Once the adsorbent material in adsorption zone 75 reaches adsorption saturation, high-temperature flue gas can be introduced into regeneration zone 72. The high-temperature flue gas enters regeneration zone 72 through high-temperature flue gas inlet pipe 71, heating and regenerating the adsorbent material. As a result, the carbon dioxide adsorbed on the material desorbs, increasing the carbon dioxide concentration in regeneration zone 72 and forming a high-concentration carbon dioxide gas stream. This high-concentration carbon dioxide is then discharged through carbon dioxide outlet 73 and finally stored in carbon dioxide storage tank 6 for subsequent transportation, utilization, or sealing. In some embodiments, the heat source entering high-temperature flue gas inlet pipe 71 can be untreated high-temperature flue gas or other suitable heat sources, as long as they can meet the desorption requirements of the adsorbent material in regeneration zone 72.

[0046] The adsorption zone 75 and regeneration zone 72 in the carbon dioxide adsorption device 7 can be understood as two functionally distinct areas. In practice, they can be two adjacent or opposite zones within the same device, or they can alternately perform adsorption and regeneration functions using a rotary, bed-switching, or valve-controlled switching structure. In some embodiments, a heat storage layer can also be provided within the carbon dioxide adsorption device 7 to buffer or recover heat between regeneration heat release and adsorption temperature regulation, thereby improving heat utilization efficiency. The heat storage layer can be configured according to actual needs.

[0047] In summary, this application establishes a treatment flue gas branch and a regeneration flue gas branch through a diversion valve 4 and a heat exchanger 1. The first stage of dehydration is completed using a regenerative regeneration wheel 9, followed by deep dehydration with the hollow dehydration assembly 2 and the gas-liquid separator 3. Subsequently, the low-temperature, low-humidity flue gas is sent to the carbon dioxide adsorption device 7 via a booster pump 5, achieving carbon dioxide adsorption, desorption, and storage. Structurally, the entire system forms a cyclical treatment path that connects dehydration and carbon dioxide capture. Functionally, it achieves staged treatment of water vapor and carbon dioxide, which helps to simultaneously improve dehydration efficiency and carbon dioxide capture efficiency, while reducing the overall energy consumption of the regeneration process.

[0048] In one application example of this application, power plant flue gas after desulfurization and denitrification is used as the treatment target. After desulfurization and denitrification, the temperature of this type of flue gas usually decreases and the moisture content increases. At this time, the flue gas is in a state that is more suitable for front-end dehydration and subsequent carbon dioxide capture and treatment.

[0049] In practical applications, the low-temperature, high-humidity flue gas treated by the desulfurization and denitrification device 8 first enters the diversion valve 4. The diversion valve 4 divides the flue gas into two paths: one path directly enters the adsorbent filling zone 91 in the regenerative regeneration wheel 9, where the adsorbent adsorbs water vapor in the flue gas, transforming this path of flue gas into low-temperature, low-humidity flue gas; the other path enters the heat exchanger 1, where it is heated by heat exchange with the high-temperature flue gas to form high-temperature, low-humidity regenerated flue gas, which then enters the regenerative regeneration wheel 9 to heat and regenerate the material in the adsorbent filling zone 91 that has adsorbed moisture. The flue gas discharged after regeneration is low-temperature, high-humidity flue gas, which then enters the hollow dehydration assembly 2 for further dehydration.

[0050] Inside the hollow dehydration assembly 2, the low-temperature, high-humidity flue gas comes into full contact with the dehydration core 22. The composite material in the dehydration core 22 further promotes moisture accumulation and converts some of the moisture into liquid water. Simultaneously, low-temperature, low-humidity flue gas can be introduced to flow along the through-cavity in the middle of the dehydration core 22 to accelerate the shedding of liquid water from the surface of the dehydration core 22. After treatment, the gas-liquid mixture flows into the gas-liquid separator 3, where the liquid water separates from the gas, resulting in further dehumidified flue gas.

[0051] In some applications of this application, the low-temperature, low-humidity flue gas output from the gas-water separator 3 can be re-entered into the subsequent primary regenerative regenerator 9 for further dehydration to further reduce the moisture content of the flue gas; the corresponding low-temperature, high-humidity flue gas discharged can be re-entered into the hollow dehydration assembly 2 for treatment. After one or more dehydration treatments, the low-temperature, low-humidity flue gas enters the carbon dioxide adsorption device 7 under the action of the booster pump 5.

[0052] When flue gas enters the adsorption zone 75 of the carbon dioxide adsorption device 7, the carbon dioxide in the flue gas is adsorbed by the metal-organic framework material until the adsorption material reaches saturation. Afterwards, the untreated high-temperature flue gas enters the regeneration zone 72 through the high-temperature flue gas inlet pipe 71, heating the adsorption material and causing the adsorbed carbon dioxide to desorb. A high-concentration carbon dioxide gas is formed in the regeneration zone 72, and this gas is introduced into the carbon dioxide storage tank 6 through the carbon dioxide outlet 73 for storage. Through the above operating conditions, pre-removal of moisture from power plant flue gas and subsequent efficient capture of carbon dioxide can be achieved.

[0053] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A system suitable for dehydration and carbon dioxide capture of flue gas, characterized in that, It includes a diversion valve (4), a heat exchanger (1), a heat storage regeneration wheel (9), a hollow dehydration assembly (2), a gas-water separator (3), a booster pump (5), a carbon dioxide adsorption device (7), and a carbon dioxide storage tank (6). The diversion valve (4) is connected to the air inlet of the heat storage regeneration wheel (9) and the air inlet of the heat exchanger (1) respectively; the heat exchanger (1) is connected to the air inlet of the heat storage regeneration wheel (9); the heat storage regeneration wheel (9) includes a rotating wheel (95), and an adsorbent filling area (91) is provided inside the rotating wheel (95); the heat storage regeneration wheel (9) is connected to the air inlet of the gas-liquid separator (3) through the hollow dehydration assembly (2); the air outlet of the gas-liquid separator (3) is connected to the air inlet of the carbon dioxide adsorption device (7) through the booster pump (5); the carbon dioxide adsorption device (7) is connected to the carbon dioxide storage tank (6) to store carbon dioxide in the carbon dioxide storage tank (6).

2. The system for flue gas dehydration and carbon dioxide capture according to claim 1, characterized in that, The diversion valve (4) has a first outlet, a second outlet, and an inlet for connecting to the flue gas pipeline to be treated. The first outlet is connected to the air inlet pipe (94) of the heat storage regeneration wheel (9), the second outlet is connected to the inlet of the heat exchanger (1), and the outlet of the heat exchanger (1) is connected to the air inlet pipe (94) of the heat storage regeneration wheel (9).

3. The system for flue gas dehydration and carbon dioxide capture according to claim 1, characterized in that, The heat storage and regeneration wheel (9) also includes an air inlet pipe (94), an air outlet pipe (92), and a sealing layer (93). The air inlet pipe (94) and the air outlet pipe (92) are respectively disposed on both sides of the rotating wheel (95), and the sealing layer (93) is disposed on the outer periphery of the rotating wheel (95).

4. The system for flue gas dehydration and carbon dioxide capture according to claim 1 or 3, characterized in that, The adsorbate filling region (91) is filled with a metal-organic framework material.

5. The system for flue gas dehydration and carbon dioxide capture according to claim 1, characterized in that, The hollow dehydration assembly (2) includes a housing (21) and a dehydration core (22) disposed within the housing (21).

6. The system for flue gas dehydration and carbon dioxide capture according to claim 5, characterized in that, The dehydration core (22) is a hollow structure with multiple through cavities extending along the axial direction.

7. The system for flue gas dehydration and carbon dioxide capture according to claim 5 or 6, characterized in that, The main material of the dehydration core (22) includes a metal-organic framework material and a template material, wherein the molecular chain of the template material has both hydrophilic and hydrophobic groups.

8. The system for flue gas dehydration and carbon dioxide capture according to claim 7, characterized in that, The metal-organic framework material is MOF-808, and the template material is poly(N-isopropylacrylamide).

9. The system for flue gas dehydration and carbon dioxide capture according to claim 5, characterized in that, The dehydration core (22) is subjected to salting treatment, and the salts used in the salting treatment include calcium chloride.

10. The system for flue gas dehydration and carbon dioxide capture according to claim 1, characterized in that, The carbon dioxide adsorption device (7) includes a high-temperature flue gas inlet pipe (71), a regeneration zone (72), a carbon dioxide outlet (73), a low-temperature and low-humidity flue gas inlet pipe (74), and an adsorption zone (75). The low-temperature and low-humidity flue gas inlet pipe (74) is connected to the adsorption zone (75), the high-temperature flue gas inlet pipe (71) is connected to the regeneration zone (72), and the carbon dioxide outlet (73) is connected to the regeneration zone (72). The low-temperature and low-humidity flue gas inlet pipe (74) is connected to the outlet of the gas-water separator (3) through the booster pump (5).

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