Adsorber, adsorption system and adsorption method

Abstract

The present application provides an adsorber, comprising a housing in which a cavity is formed, and a plurality of spaced adsorption bed layers and a plurality of gas flow uniform distribution plates which are located in the cavity, wherein the housing is further provided with a plurality of gas inlets and a gas outlet, the gas inlets are used for respectively injecting, into the cavity, gas to be adsorbed and regenerated gas, and the gas outlet is used for outputting adsorbed gas and desorbed gas; a gap between two adjacent adsorption bed layers forms a channel, the channel is separately communicated with the gas inlets and the gas outlet, and the width of the channel is gradually increased in the direction towards the gas inlets and is gradually reduced in the direction towards the gas outlet; the inlets of the plurality of gas flow uniform distribution plates are all communicated with the gas inlets, and the outlets of the gas flow uniform distribution plates face the adsorption bed layers; the aperture of the gas flow uniform distribution plates is gradually reduced from the inlets of the gas flow uniform distribution plates to the outlets of the gas flow uniform distribution plates. The present application is used for reducing bed pressure drop, and improving the adsorption and desorption efficiency.

Description

Adsorber, adsorption system and adsorption method

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on March 25, 2024, with application number CN 202410346473.0 and application name “An Adsorbent, Adsorption System and Adsorption Method”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present application belongs to the technical field of direct air capture of carbon dioxide, and specifically relates to an adsorber, a direct air capture system and an adsorption method. Background Art

[0003] As global greenhouse gas emissions continue to rise, climate change has become a global issue. Many regions have pledged to achieve net-zero emissions or carbon neutrality within the coming decades. Direct Air Capture (DAC) technology offers an effective means of achieving these goals, removing carbon dioxide from the atmosphere, thereby contributing to climate change mitigation and greenhouse gas emissions. While DAC technology has significant potential for climate change mitigation, its widespread adoption requires addressing a number of challenges and bottlenecks.

[0004] The application of DAC technology involves the construction of large-scale adsorbers and related infrastructure. Large-scale adsorbers have been developing towards larger sizes and lower energy consumption. The emergence of vertical radial flow adsorbers has effectively solved the problems of large floor space and difficult leveling of molecular sieve beds in vertical axial and horizontal vertical flow adsorbers. However, due to the continued increase in air processing capacity, the concentration of carbon dioxide in the air is very low. Therefore, high-throughput, low-concentration direct air capture carbon dioxide systems generally suffer from high system pressure drop and low adsorption and regeneration efficiency. Summary of the Invention

[0005] The present application provides an adsorber for solving the problems of high system pressure drop, low adsorption and desorption efficiency, etc. in the prior art when adsorbing high-throughput, low-concentration gas components.

[0006] The present application provides an adsorption method for the above adsorber, which is simple to operate, improves adsorption and desorption efficiency, and reduces operating costs.

[0007] The present application also provides an adsorption system comprising the above adsorber, which reduces system pressure drop and improves adsorption and desorption efficiency.

[0008] On the one hand, the present application provides an adsorber, comprising a shell having a cavity therein, and a plurality of adsorption beds arranged at intervals in the cavity, and a plurality of air flow distribution plates, the shell further being provided with a plurality of air inlets and air outlets, the air inlets being used to inject the gas to be adsorbed and the regeneration gas into the cavity respectively, and the air outlets being used to output the adsorbed gas and the desorbed gas;

[0009] The interval between two adjacent adsorption beds forms a channel, the channel is connected to the air inlet and the air outlet respectively, and the width of the channel gradually decreases in the direction of the air inlet and the air outlet;

[0010] The inlets of the plurality of air flow distribution plates are all connected to the air inlet, and the outlets of the air flow distribution plates face the adsorption bed layer;

[0011] The aperture of the airflow distribution plate decreases gradually from the inlet to the outlet of the airflow distribution plate.

[0012] Furthermore, a plurality of adsorption beds are spaced apart in the axial or radial direction of the shell; wherein,

[0013] At least one of the air inlets is provided on the housing corresponding to the channel; and / or,

[0014] At least one of the air outlets is provided on the housing corresponding to the channel.

[0015] Furthermore, the channel corresponding to the air inlet is different from the channel corresponding to the air outlet; and / or,

[0016] A partition is provided in the middle of the channel corresponding to the air inlet.

[0017] Furthermore, the thickness of the adsorption bed is 1-20 cm; and / or,

[0018] The thickness of the air flow distribution plate is 2-5 mm; and / or,

[0019] The ratio of the aperture at the outlet of the airflow uniform distribution plate to the aperture at the inlet of the airflow uniform distribution plate is 1:(2-5).

[0020] Furthermore, the ratio of the width of the channel to the thickness of the adsorption bed is 1:(2-10).

[0021] Furthermore, a pressure monitoring gauge is provided, the pressure monitoring gauge being used to monitor the pressure of the first end face and the second end face of the adsorption bed layer which are arranged opposite to each other in the thickness direction; and / or,

[0022] A temperature monitoring meter is also provided, and the temperature monitoring meter is used to monitor the temperature of a first end surface and a second end surface of the adsorption bed layer that are arranged opposite to each other in the thickness direction; and / or,

[0023] The shell is further provided with a liquid outlet, which is used to discharge the condensate in the adsorption bed; and / or,

[0024] The outer side of the shell is also covered with a heat-insulating layer.

[0025] On the other hand, the present application provides an adsorption method of the adsorber described above, comprising the following steps:

[0026] (1) The gas to be adsorbed is sent to the cavity in the adsorber through the air inlet, dispersed by the air flow distribution plate, and then enters the adsorption bed for adsorption treatment to obtain adsorbed gas and a saturated adsorption bed, and the adsorbed gas is extracted through the air outlet;

[0027] (2) vacuuming the remaining gas in the adsorber until the pressure in the adsorber is -85 kPa to -95 kPa;

[0028] (3) delivering the regenerated gas to the cavity in the adsorber through the air inlet, dispersing the gas through the air flow distribution plate, and regenerating the saturated adsorption bed to obtain desorbed gas, condensate, and a regenerated adsorption bed; the desorbed gas is extracted through the air outlet;

[0029] (4) Cooling the regenerated adsorption bed.

[0030] Furthermore, when the gas to be adsorbed is air and the desorbed gas is carbon dioxide, the adsorption bed comprises an adsorbent, and the ratio of the mass of the adsorbent to the adsorption amount of the carbon dioxide is 0.9-2 mmol / g; and / or,

[0031] The adsorbent has a particle size distribution of 0.3 mm to 1.5 mm, and the adsorbent comprises a solid amine adsorption material; and / or,

[0032] In step (1), the amount of gas to be adsorbed is 200-300 Nm 3 / h; the adsorption treatment temperature is 20-40 ° C, the time is 100-120min; and / or,

[0033] In step (3), the regeneration gas is water vapor, the temperature of the regeneration treatment is 80-120° C., and the time is 10-30 minutes; the regeneration treatment includes steam direct purge regeneration treatment.

[0034] On the other hand, the present application provides an adsorption system comprising the adsorber described above.

[0035] Furthermore, it also includes a gas purification and cooling device for adsorbed gas, an adsorption device, a regeneration gas generating device, and a separation device;

[0036] Wherein, the adsorption device comprises at least one adsorber;

[0037] The outlet of the adsorbed gas purification cooling device is connected to the air inlet of the adsorber, and the air outlet of the adsorber is used to output the adsorbed gas;

[0038] The outlet of the regeneration gas generating device is connected to the air inlet of the adsorber, and the air outlet of the adsorber is also connected to the inlet of the separation device. The gas phase outlet of the separation device is used to output product gas, and the liquid phase outlet of the separation device is connected to the reflux port of the regeneration gas generating device.

[0039] The present application provides an adsorber, which, through the spaced arrangement of multiple adsorption beds, multiple air inlets and outlets, and specially structured channels, cooperates with each other, so that the airflow enters the cavity inside the adsorber through multiple air inlets, and then passes through the airflow distribution plate and the adsorption bed in sequence along the direction of airflow flow, which can reduce the bed pressure drop and improve the adsorption and desorption efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] FIG1 is a schematic diagram of the adsorber structure in a specific embodiment of the present application;

[0041] FIG2 is a schematic diagram of the adsorber structure in a specific embodiment of the present application;

[0042] FIG3 is a schematic diagram of an adsorption system in a specific embodiment of the present application;

[0043] FIG4 is a schematic diagram of an adsorption system in a specific embodiment of the present application;

[0044] Figure 5 is a graph showing the change of CO2 concentration at the adsorption outlet versus adsorption time;

[0045] Figure 6 is a graph showing the change of CO2 adsorption capacity at the adsorption outlet versus adsorption time;

[0046] FIG7 is a comparison chart of regeneration rates of different regeneration treatment methods;

[0047] Figure 8 is a graph showing the change in adsorption capacity at different temperatures;

[0048] FIG9 is a graph showing pressure changes over time during vacuum treatment;

[0049] FIG10 shows the temperature change over time during the cooling process.

[0050] Explanation of Reference Numerals: 1: Shell; 2: First end face; 3: Second end face; 4: Adsorption bed; 5: Pressure gauge; 6: Air flow distribution plate; 7: Air inlet; 8: Air outlet; 9: Temperature gauge; 10: Liquid outlet; 11: Vent pipe; 12: Air inlet channel; 13: Air outlet channel; 16: Adsorbent loading inlet; 17: Adsorbent replacement outlet; 18: Partition; C1: Purification and cooling device for adsorbed gas; T1: Adsorption device; K1: Regeneration gas generator; F1: Separation device; K01: Steam generator; K02: Flow regulating unit; K03: Steam boiler softening water treatment unit; F01: Condenser; F02: Gas-liquid separator; F03, T07: Online infrared gas analyzer; F04: Vacuum pump; F05: Circulating water cooling unit; T01-T04: Adsorber; T05: Vacuum equipment; T06: Blower; T08: Automatic control system and instrumentation. DETAILED DESCRIPTION

[0051] To make the purpose, technical solutions, and advantages of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0052] On the one hand, the present application provides an adsorber. FIG1 is a schematic diagram of the adsorber structure in a specific embodiment of the present application. As shown in FIG1 , the adsorber comprises a shell 1 having a cavity therein, and a plurality of adsorption beds 4 arranged at intervals in the cavity, and a plurality of air flow distribution plates 6. The shell 1 is further provided with a plurality of air inlets 7 and air outlets 8. The air inlets 7 are used to inject the gas to be adsorbed and the regeneration gas into the cavity, respectively, and the air outlets 8 are used to output the adsorbed gas and the desorbed gas.

[0053] The gap between two adjacent adsorption beds 4 forms a channel, which is connected to the air inlet 7 and the air outlet 8 respectively, and the width of the channel gradually decreases in the direction of the air inlet and the air outlet;

[0054] The inlets of the plurality of air flow distribution plates 6 are all connected to the air inlet 7, and the outlets of the air flow distribution plates face the adsorption bed 4;

[0055] The aperture of the airflow distribution plate 6 decreases gradually from the inlet to the outlet of the airflow distribution plate 6 .

[0056] In this application, "multiple" means greater than or equal to two, and the number of "multiple" can be the same or different; this application does not limit the specific form of each part; wherein, the housing 1 with a cavity inside can be circular or square;

[0057] A plurality of adsorption beds 4 are arranged in the cavity inside the shell 1. The present application does not limit the shape of the adsorption bed 4, which can be rectangular or trapezoidal. The adsorption bed 4 is filled with adsorbent, and the adsorption bed 4 is provided with a supporting layer in the thickness direction. The supporting layer does not penetrate the adsorbent with the smallest particle size and allows the gas to pass smoothly. Optionally, the supporting layer can be a fabric or a plate-like structure; the airflow enters the plurality of adsorption beds 4 for adsorption or regeneration treatment, thereby improving the adsorption and desorption efficiency.

[0058] The airflow distribution plate 6 can achieve distribution and collection of airflow. The airflow distribution plate 6 is evenly provided with small holes to evenly distribute the airflow to the adsorption bed, thereby reducing the pressure drop of the bed and avoiding the concentration of airflow in certain areas. At the same time, it plays a role in filtering impurities in the gas to be adsorbed, thereby improving the adsorption and desorption efficiency.

[0059] The housing 1 is further provided with a plurality of air inlets 7 and air outlets 8, through which gas can simultaneously enter or leave the cavity in the adsorber; the air inlets 7 are used to inject the gas to be adsorbed and the regeneration gas into the cavity, respectively, and the air outlets 8 are used to output the adsorbed gas and the desorbed gas, respectively. It can be understood that when the gas to be adsorbed is injected into the cavity, the adsorbed gas is output; when the regeneration gas is injected into the cavity, the desorbed gas is output;

[0060] The gap between two adjacent adsorption beds 4 constitutes a channel, which is respectively connected to the air inlet 7 and the air outlet 8. Specifically, the channel connected to the air inlet 7 is the air inlet channel 12, and the gas enters the adsorption bed 4 through the air inlet channel 12. The channel connected to the air outlet 8 is the air outlet channel 13, and the gas leaves the adsorption bed through the air outlet channel 13. The width of the channel gradually decreases according to the air flow direction of the air inlet and the air outlet. After the gas enters the channel through the air inlet, the cross-sectional area of ​​the channel becomes smaller and smaller from near the inlet to far away from the inlet, so that the air flow velocity at the corresponding cross section is kept consistent, and the air flow can effectively utilize the air flow uniformly distributed by the air flow uniformly distributed plate;

[0061] After the air flow enters the cavity in the adsorber through the air inlet 7, it flows through the inlet of the air flow distribution plate 6, and is dispersed by the air flow distribution plate. After being dispersed and evenly distributed, the air flow leaves through the outlet of the air flow distribution plate and enters the adsorption bed 4; the aperture of the air flow distribution plate 6 gradually decreases from the inlet to the outlet of the air flow distribution plate 6, forming a frustum shape, which can effectively distribute the air flow, reduce the air flow resistance and thus reduce the bed pressure drop;

[0062] The adsorber provided in the present application cooperates with each other through the spaced arrangement of multiple adsorption beds, multiple air inlets and outlets, and specially structured channels, so that the airflow enters the cavity inside the adsorber through multiple air inlets, and then passes through the airflow distribution plate and the adsorption bed in sequence along the direction of airflow flow, which can reduce the bed pressure drop and improve the adsorption and desorption efficiency.

[0063] Optionally, a plurality of adsorption beds 4 are spaced apart in the axial or radial direction of the shell 1 ; wherein at least one air inlet 7 is provided on the shell corresponding to the channel; and at least one air outlet 8 is provided on the shell corresponding to the channel.

[0064] The present application does not limit the setting direction of the adsorption bed 4. Multiple adsorption beds 4 can be spaced apart in the radial direction of the shell 1 (as shown in Figure 1), or can be spaced apart in the axial direction of the shell 1 (as shown in Figure 2); in one specific embodiment, at least one air inlet 7 is provided on the shell 1 corresponding to the channel, so that the airflow can enter the closed shell 1 through the air inlet 7, and the gas to be adsorbed and the regenerated gas can share one air inlet, or can be further subdivided into two parallel air inlets; in another specific embodiment, at least one air outlet 8 is provided on the shell 1 corresponding to the channel, so that the airflow can leave the closed shell 1 through the air outlet 8, and the adsorbed gas and the desorbed gas can share one air outlet, or can be further subdivided into two parallel air outlets.

[0065] Furthermore, the channel corresponding to the air inlet 7 is different from the channel corresponding to the air outlet 8 .

[0066] It can be understood that the channel corresponding to the air inlet 7 is different from the channel corresponding to the air outlet 8, which means that each channel can and can only be provided with an air inlet or an air outlet, so that the air flow enters the path to leave the adsorber and passes through at least one adsorption bed layer, thereby improving the adsorption and desorption efficiency.

[0067] In one embodiment, a partition 18 is provided in the middle of the channel corresponding to the air inlet;

[0068] It can be understood that adding a partition 18 in the middle of the air inlet channel can evenly divide the gas to be adsorbed into two parts when entering the air inlet channel, which helps to further distribute the airflow, reduce the bed pressure drop and improve the adsorption and regeneration efficiency.

[0069] Specifically, the thickness of the adsorption bed 4 is 1-20 cm.

[0070] The thickness of the adsorption bed refers to the average path length of the airflow through the adsorption bed. It can be understood that the thickness of the adsorption bed is closely related to the resistance encountered by the airflow penetrating therethrough. The applicant has found that when the thickness of the adsorption bed 4 is 1-20 cm, the adsorption and desorption efficiency can be guaranteed while further reducing the bed pressure drop and improving the mass transfer efficiency.

[0071] In a specific embodiment of the present application, the thickness of the airflow distribution plate is 2-5 mm; the ratio of the aperture at the outlet of the airflow distribution plate to the aperture at the inlet of the airflow distribution plate is 1:(2-5);

[0072] It can be understood that the air flow uniform distribution plate is a plate-like structure with a certain thickness and distributed small holes. Since the aperture gradually decreases from the inlet to the outlet, it is truncated into a cone shape. The applicant has found through research that when the thickness of the air flow uniform distribution plate is 2-5 mm and the ratio of the aperture at the outlet of the air flow uniform distribution plate to the aperture at the inlet of the air flow uniform distribution plate is 1: (2-5), the air flow resistance can be further reduced, the air flow can be evenly distributed, and the bed pressure drop can be further reduced.

[0073] Furthermore, the ratio of the width of the channel to the thickness of the adsorption bed 4 is 1:(2-10).

[0074] Since the channel gradually widens along the flow direction of the airflow, the width of the channel refers to the average width. The applicant has found that when the ratio of the channel width to the thickness of the adsorption bed is 1:(2-10), it is more conducive to the airflow to efficiently pass through the adsorption bed, reduce the bed pressure drop, and improve the mass transfer efficiency.

[0075] In one embodiment, a pressure monitoring gauge 5 is further provided, and the pressure monitoring gauge 5 is used to monitor the pressure of the first end surface 2 and the second end surface 3 that are arranged opposite to each other in the thickness direction of the adsorption bed 4;

[0076] The present application does not limit the specific setting method of the pressure detection gauge 5. It can be set on the shell 1 or not. Any method that can monitor and output the pressure of the first end face 2 and the second end face 3 of the adsorption bed 4 that are relatively set in the thickness direction can be used.

[0077] In another specific embodiment, a temperature monitoring meter 9 is further provided, and the temperature monitoring meter 9 is used to monitor the temperature of the first end surface 2 and the second end surface 3 of the adsorption bed 4 which are arranged opposite to each other in the thickness direction;

[0078] The present application does not limit the specific setting method of the temperature monitoring meter 9. It can be set on the shell 1 or not. Any method that can monitor and output the temperatures of the first end face 2 and the second end face 3 of the adsorption bed 4 that are relatively set in the thickness direction can be used.

[0079] In another specific embodiment, the housing 1 is further provided with a liquid outlet 10, which is used to discharge the condensate in the adsorption bed 4;

[0080] It is understandable that condensate may be generated during the adsorption or desorption process, so a liquid outlet 10 is provided on the shell 1 to discharge the condensate in the adsorption bed 4 and the shell 1, thereby further improving the mass transfer efficiency and reducing the bed pressure drop.

[0081] Furthermore, the outer side of the shell 1 is also covered with an insulation layer; by providing the insulation layer on the outer side of the shell 1, it is beneficial to keep the temperature inside the adsorber constant, further improve the adsorption and desorption efficiency, and maintain the reaction stability.

[0082] Optionally, the shell 1 is also provided with an adsorbent filling inlet 16 and an adsorbent replacement outlet 17. The adsorbent filler is first naturally filled into the upper part of the adsorption bed 4 through the adsorbent filling inlet 16, and then pressurized air is used for auxiliary filling; when the adsorbent needs to be replaced, the adsorbent filler is discharged and replaced through the adsorbent replacement outlet 17; a vent pipe 11 is also provided on the upper part of the shell 1, which helps to adjust the pressure inside the adsorber, etc.

[0083] On the other hand, the present application also provides an adsorption method of the above adsorber, comprising the following steps:

[0084] (1) The gas to be adsorbed is sent to the cavity in the adsorber through the air inlet, dispersed by the air flow distribution plate, and then enters the adsorption bed for adsorption treatment to obtain adsorbed gas and a saturated adsorption bed. The adsorbed gas is extracted through the air outlet;

[0085] (2) Vacuum the remaining gas in the adsorber until the pressure in the adsorber is -85kPa to -95kPa;

[0086] (3) The regenerated gas is sent to the cavity in the adsorber through the air inlet, and after being dispersed by the air flow distribution plate, the saturated adsorption bed is regenerated to obtain desorbed gas, condensate and regenerated adsorption bed; the desorbed gas is collected through the air outlet;

[0087] (4) Cooling the regenerated adsorption bed.

[0088] The adsorption method provided in the present application is applicable to any treatment that directly utilizes a solid adsorbent to adsorb a gas; specifically, in step (1), the gas to be adsorbed is sent to the cavity in the adsorber through the air inlet, and after being dispersed by the air flow uniform distribution plate, enters the adsorption bed for adsorption treatment to remove the components to be adsorbed in the gas to be adsorbed; it can be understood that the adsorber is also provided with a gas analyzer at the air inlet and the air outlet, respectively, for detecting the concentration of the components to be adsorbed in the gas to be adsorbed, and obtaining the inlet concentration and the outlet concentration respectively. When the outlet concentration is equivalent to the inlet concentration, it is proved that the adsorbent in the adsorption bed is saturated with adsorption, and the adsorption treatment is stopped at this time to obtain the adsorbed gas after the components to be adsorbed are separated and the saturated adsorption bed, and the adsorbed gas is extracted through the air outlet and leaves the adsorber;

[0089] In step (2), the remaining gas in the adsorber is vacuumed until the pressure in the adsorber is -85kPa to -95kPa; this is beneficial to improving regeneration efficiency and reducing costs;

[0090] In step (3), the regenerated gas is sent to the cavity in the adsorber through the air inlet, and after being dispersed by the air flow uniform distribution plate, the saturated adsorption bed is regenerated to desorb the components to be adsorbed that are enriched in the saturated adsorption bed. It can be understood that the air outlet of the adsorber is also connected to a separation device, a gas analyzer, etc., for separating and detecting the flow rate of the desorbed gas. When the flow rate of the desorbed gas is detected to be 0 L / min, it indicates that all the components to be adsorbed in the adsorption bed have been desorbed. At this time, the regeneration process is stopped to obtain desorbed gas rich in the components to be adsorbed, condensate and a regenerated adsorption bed. The desorbed gas is extracted through the air outlet and leaves the adsorber, and the condensate is discharged through the liquid outlet.

[0091] In step (4), the regenerated adsorption bed is cooled, which is beneficial to improving the efficiency of the next adsorption treatment; steps (1) to (4) are one cycle of the adsorption method provided in this application, and step (1) is directly performed after step (4) to start the next round of adsorption treatment.

[0092] The adsorption method of the adsorber provided in the present application is simple and easy to implement, which is beneficial to reducing the bed pressure drop and improving the mass transfer efficiency of the gas. The adsorption bed can be regenerated indefinitely, and the treatment process does not consume auxiliary materials, thereby improving the adsorption and regeneration efficiency and helping to reduce operating costs.

[0093] Specifically, when the gas to be adsorbed is air and the desorbed gas is carbon dioxide, the adsorption bed includes an adsorbent, and the ratio of the mass of the adsorbent to the adsorption amount of carbon dioxide is 0.9-2 mmol / g; the particle size distribution of the adsorbent is 0.3 mm to 1.5 mm, and the adsorbent includes a solid amine adsorption material; in step (1), the amount of gas to be adsorbed is 200-300 Nm 3 / h; the adsorption treatment temperature is 20-40 ° C and the time is 100-120 min; in step (3), the regeneration gas is water vapor, the regeneration treatment temperature is 80-120 ° C and the time is 10-30 min; the regeneration treatment includes steam direct purge regeneration treatment.

[0094] The following is an example of directly capturing carbon dioxide in air. In this case, the gas to be adsorbed is air, and the component to be adsorbed and the desorbed gas are carbon dioxide. The applicant found that the ratio of the mass of the adsorbent to the adsorption amount of carbon dioxide is 0.9-2 mmol / g; the particle size distribution of the adsorbent is 0.3 mm to 1.5 mm, and the adsorbent includes a solid amine adsorption material, specifically, the adsorbent is a solid amine adsorption material with amine functionalized grafted amino functional groups; in step (1), the amount of gas to be adsorbed is 200-300 Nm 3 / h; the temperature of the adsorption treatment is 20-40°C and the time is 100-120min; in step (3), the regeneration gas is water vapor, the temperature of the regeneration treatment is 80-120°C and the time is 10-30min; the regeneration treatment includes steam direct purge regeneration treatment; under the limitation of the above parameters, it is beneficial to further improve the adsorber's capture efficiency of carbon dioxide in the air.

[0095] On the other hand, the present application also provides an adsorption system, comprising the adsorber described above.

[0096] The adsorption system including the adsorber described above can reduce the bed pressure drop of the gas in the adsorber, improve the adsorption and regeneration efficiency, and reduce the operating cost.

[0097] Specifically, FIG3 is a schematic diagram of an adsorption system in a specific embodiment of the present application. As shown in FIG3 , it further includes a gas purification and cooling device C1 to be adsorbed, an adsorption device T1, a regeneration gas generating device K1, and a separation device F1;

[0098] Wherein, the adsorption device T1 includes at least one adsorber;

[0099] The outlet of the adsorbed gas purification cooling device C1 is connected to the air inlet of the adsorber, and the air outlet of the adsorber is used to output the adsorbed gas;

[0100] The outlet of the regeneration gas generator K1 is connected to the air inlet of the adsorber, and the air outlet of the adsorber is also connected to the inlet of the separation device F1. The gas phase outlet of the separation device F1 is used to output product gas, and the liquid phase outlet of the separation device F1 is connected to the reflux port of the regeneration gas generator K1.

[0101] In the description of this application, it should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to a fixed connection, a connection through an intermediary medium, internal communication between two components, or an interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0102] The present application does not limit the specific form of each unit, wherein the adsorbed gas purification and cooling device C1 can filter impurities in the adsorbed gas and reduce its temperature; the adsorption device T1 includes at least one of the above-mentioned adsorbers, and the adsorbers can be connected in parallel or in series; the regeneration gas generating device K1 can generate regeneration gas; and the separation device F1 can separate the adsorbed components in the desorbed gas from the regeneration gas.

[0103] Specifically, the inlet of the gas purification cooling device C1 to be adsorbed is the inlet of the adsorption system. The gas to be adsorbed enters the gas purification cooling device C1 through the inlet of the gas purification cooling device C1, is filtered, purified and cooled, leaves through the outlet of the gas purification cooling device C1, and enters the adsorption device T1 through the air inlet of the adsorber, where it is adsorbed. After the adsorption process is completed, the adsorbed gas and the saturated adsorption bed are obtained; the adsorbed gas is extracted through the air outlet of the adsorber and leaves the adsorption system; the outlet of the regeneration gas generating device K1 is also connected to the air inlet of the adsorber. The regenerated gas is produced through the outlet of the regeneration gas generator K1 and enters the adsorber through the air inlet of the adsorber to regenerate the saturated adsorption bed, desorbing the components to be adsorbed in the saturated adsorption bed to obtain a regenerated adsorption bed and desorbed gas. The desorbed gas is produced through the air outlet of the adsorber and enters the separation device F1 through the inlet of the separation device F1, where the components to be adsorbed are separated from the regenerated gas to obtain desorbed gas and regeneration circulating liquid. The desorbed gas leaves through the gas phase outlet of the separation device F1 and outputs product gas. The regeneration circulating liquid is connected to the reflux port of the regeneration gas generator K1 to recover the regenerated gas.

[0104] FIG4 is a schematic diagram of an adsorption system in a specific embodiment of the present application. As shown in FIG4 , when the adsorption system is used to directly capture carbon dioxide from air, the regeneration gas generating device includes a steam generator K01 and a flow regulating unit K02. The steam generator K01 is used to heat the room temperature supply water to boiling and generate sufficient steam for heating the adsorbent. The flow regulating unit K02 mainly includes an opening regulating valve and a flow meter, and adjusts the steam flow rate through a PID control system.

[0105] The separation device includes a condenser F01, a gas-liquid separator F02, an online infrared gas analyzer F03, a vacuum pump F04, a circulating water cooling unit F05, etc. Among them, the condenser F01 is used to condense the desorbed carbon dioxide and water vapor mixture to a certain temperature and remove most of the water therein; the gas-liquid separator F02 is used to separate the carbon dioxide gas from the water; the online infrared gas analyzer F03 is used to detect the purity of the separated carbon dioxide product gas; the vacuum pump F04 helps to extract the carbon dioxide product gas after gas-liquid separation; and the circulating water cooling unit F05 is used to circulate and cool the condenser F01.

[0106] The adsorption device includes four parallel-connected adsorbers T01-T04, vacuum equipment T05, blower T06, online infrared gas analyzer T07, automatic control system and instrument T08, etc. Among them, the vacuum equipment T05 is used to extract the remaining air in the adsorber and promptly extract the residual gas during the desorption and regeneration process to accelerate the adsorption and regeneration efficiency; the blower T06 is used to pass air into the adsorber and overcome sufficient resistance along the way; the online infrared gas analyzer T07 is used to detect concentration changes at the air inlet and outlet of the adsorber in real time; the automatic control system and instrument T08 are used to timely adjust the flow rate, and all valves are connected to the programmable logic controller (PLC), which controls the operation of the entire system.

[0107] Optionally, the adsorption system also includes a steam boiler softened water treatment unit K03, which is used to treat the discharged liquid from the condensation section at the bottom of the adsorption tower; specifically, the liquid outlet of the adsorber and the liquid phase outlet of the gas-liquid separator are respectively connected to the inlet of the steam boiler softened water treatment unit, and the outlet of the steam boiler softened water treatment unit is connected to the reflux port of the steam generator.

[0108] The adsorber provided in this application is described in detail below through specific examples.

[0109] Example 1

[0110] This embodiment uses an adsorber as shown in FIG1 , wherein four adsorption beds are spaced apart in the axial direction, the number of air inlets is two, the number of air outlets is three, and the number of uniform distribution plates is four; the thickness of the adsorption bed is 10 cm; the ratio of the width of the channel to the thickness of the adsorption bed is 1:2; the thickness of the air flow uniform distribution plate is 3 mm; and the ratio of the aperture at the outlet of the air flow uniform distribution plate to the aperture at the inlet of the air flow uniform distribution plate is 1:3;

[0111] This embodiment performs adsorption treatment on carbon dioxide in the air, where the concentration of carbon dioxide in the air is 400 ppm, and includes the following steps:

[0112] (1) Air is sent to the cavity in the adsorber through the air inlet, and the air flow rate is 260Nm 3 / h, after being dispersed by the air flow distribution plate, it enters the adsorption bed for adsorption treatment. The adsorbent set in the adsorption bed is a solid amine adsorption material with amine functionalization grafted with amino functional groups, and its particle size is 0.6mm. The adsorption treatment temperature is 20℃ and the time is 120min. The adsorbed air and saturated adsorption bed are obtained, and the adsorbed air is collected through the outlet.

[0113] (2) The remaining gas in the adsorber is vacuumed for 5 min, and the pressure in the adsorber is -95 kPa;

[0114] (3) The water vapor is sent to the cavity in the adsorber through the air inlet, and the amount of water vapor introduced is 1Nm 3 / h, after being dispersed by the air flow distribution plate, the saturated adsorption bed is regenerated by direct steam purge at a temperature of 120°C and a time of 15 minutes to obtain carbon dioxide, condensate and a regenerated adsorption bed; carbon dioxide is extracted through the outlet;

[0115] (4) Air is introduced to cool the regenerated adsorption bed. The cooling temperature is the ambient temperature and the cooling time is 10 minutes.

[0116] Example 2

[0117] The difference between this embodiment and embodiment 1 is that in step (1), the adsorption treatment time is 60 minutes.

[0118] Example 3

[0119] The difference between this embodiment and embodiment 1 is that in step (1), the adsorption treatment time is 180 minutes.

[0120] Example 4

[0121] The difference between this embodiment and embodiment 1 is that in step (1), the adsorption treatment temperature is 10°C.

[0122] Example 5

[0123] The difference between this embodiment and embodiment 1 is that in step (3), the regeneration process uses steam-assisted heat exchange.

[0124] Example 6

[0125] The difference between this embodiment and embodiment 1 is that: an adsorber as shown in Figure 2 is used, wherein four adsorption beds are spaced apart in the axial direction, the number of air inlets is 2, the number of air outlets is 2, and the number of uniform distribution plates is 2; the thickness of the adsorption bed is 10 cm; and the ratio of the channel width to the thickness of the adsorption bed is 1:2.

[0126] Example 7

[0127] The difference between this embodiment and embodiment 1 is that the thickness of the adsorption bed is 20 cm.

[0128] Example 8

[0129] The difference between this embodiment and embodiment 1 is that the ratio of the channel width to the adsorption bed thickness is 1:10.

[0130] Comparative Example 1

[0131] The difference between this comparative example and Example 1 is that: the number of adsorption beds is 1, the number of air inlets is 1, the number of air outlets is 1 and the number of uniform distribution plates is 1; the thickness of the adsorption bed is 40 cm.

[0132] Test Example 1

[0133] The adsorbed air in the embodiment and the comparative example was detected by an online infrared gas analyzer; wherein, the average CO2 adsorption amount = (inlet concentration - outlet concentration) × air flow × adsorption time / adsorbent mass;

[0134] The calculation formula of CO2 capture rate is:

[0135] Wherein, CCR is CO2 capture rate, in %; is the average CO2 concentration at the outlet during the adsorption time, Q is the average CO2 concentration at the air inlet during the adsorption time, in ppm; feed is the outlet flow rate during the adsorption time, Q purge The outlet flow rate during the adsorption time, in L / min;

[0136] The bed pressure drop is calculated by the classic Ergun formula:

[0137] Z is the thickness of the adsorption bed, in cm; ε is the porosity of the adsorption bed, in %; d p is the average particle size of the adsorbent, in mm; u is the superficial velocity of the adsorption bed, in m / s; ρ is the gas density, in kg / m 3 ; μ is the gas viscosity, unit is Pa·s.

[0138] The measured results are shown in Figures 5, 6 and Table 1.

[0139] Figure 5 shows the change of CO2 concentration at the adsorption outlet with adsorption time, where Figures 1, 3-6 are repeated tests with an adsorption time of 60 minutes, Figure 2 is an adsorption time of 180 minutes, and Figures 7-10 are repeated tests with an adsorption time of 120 minutes. Figure 6 shows the change of CO2 adsorption capacity at the adsorption outlet with adsorption time. As can be seen from the figure, when the adsorption time is 60 minutes, the adsorption capacity is 0.88 to 1.1 mmol / g; when the adsorption time is 120 minutes, the adsorption capacity is 1.35 to 1.62 mmol / g. At the same time, when the adsorption time is 180 minutes, the adsorption capacity only increases by 13%. When the adsorption time is 100 to 120 minutes, more than 80% of the saturated adsorption capacity has been achieved. Therefore, this application recommends an adsorption time of 100 to 120 minutes to ensure adsorption efficiency while reducing operating costs.

[0140] Table 1

[0141] It can be seen from Table 1 that, compared with Comparative Example 1, the adsorber and adsorption method provided in the present application can effectively reduce the bed pressure drop and improve the adsorption and regeneration efficiency of carbon dioxide.

[0142] Test Example 2

[0143] The temperature change of the adsorption bed during the regeneration process in Example 1 and Example 5 was tested using a temperature monitoring meter. The results are shown in FIG7 .

[0144] FIG7 is a comparison chart of the regeneration rates of different regeneration treatment methods, in which both the auxiliary heat exchange regeneration and the direct steam purge regeneration were repeated twice. As shown in FIG7 , the average temperature of the water vapor assisted heat exchange in Example 5 is about 82° C., and the regeneration time is relatively long at 90 min. The average temperature of the steam direct purge regeneration in Example 1 is about 100° C., and the regeneration time is about 25 min. Therefore, the use of direct steam purge regeneration can greatly increase the regeneration rate, shorten the regeneration time, and improve the adsorber operating efficiency.

[0145] Test Example 3

[0146] The air after adsorption in Example 1 and Example 4 was detected by an online infrared gas analyzer, and the temperature of the adsorption bed during the adsorption process was detected by a temperature monitoring meter, to obtain FIG8 .

[0147] Figure 8 is a graph showing the change in adsorption capacity at different temperatures. In Example 4, the average temperature of the adsorption process is 35-40°C, and the average adsorption capacity for 60 min is about 0.65 mmol / g; in Example 1, the average temperature of the adsorption process is 15-20°C, and the average adsorption capacity for 60 min is about 0.97 mmol / g. It can be seen that a lower adsorption temperature is conducive to the adsorption process. Therefore, when the adsorption temperature is 10-20°C, it is more conducive to ensuring efficient adsorption.

[0148] Test Example 4

[0149] The pressure change in the adsorber during the vacuum treatment in step (2) of Example 1 was detected using a pressure gauge. The result is shown in FIG9 .

[0150] FIG9 is a graph showing the change of pressure over time during the vacuum treatment. As can be seen from the graph, the pressure in the adsorber can be reduced to the target value within 5-10 minutes.

[0151] Test Example 5

[0152] The temperature change of the adsorption bed during the cooling process in step (4) of Example 1 was tested using a temperature monitoring meter. The results are shown in FIG10 .

[0153] Figure 10 shows the temperature change over time during the cooling process. Using air cooling can reduce the bed temperature to room temperature in about 10 minutes, which improves the cooling efficiency, reduces the energy consumption of the regeneration process, greatly reduces the adsorber regeneration cooling operation time and shortens the adsorption / desorption cycle time.

[0154] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An adsorber, wherein: The invention comprises a shell having a cavity therein, a plurality of adsorption beds arranged at intervals in the cavity, and a plurality of air flow distribution plates. The shell is further provided with a plurality of air inlets and air outlets. The air inlets are used to inject the gas to be adsorbed and the regeneration gas into the cavity respectively, and the air outlets are used to output the adsorbed gas and the desorbed gas. The interval between two adjacent adsorption beds forms a channel, the channel is connected to the air inlet and the air outlet respectively, and the width of the channel gradually decreases in the direction of the air inlet and the air outlet; The inlets of the plurality of air flow distribution plates are all connected to the air inlet, and the outlets of the air flow distribution plates face the adsorption bed layer; The aperture of the airflow distribution plate decreases gradually from the inlet to the outlet of the airflow distribution plate.

2. The adsorber according to claim 1, wherein The plurality of adsorption beds are spaced apart in the axial or radial direction of the shell; wherein at least one of the air inlets is arranged on the shell corresponding to the channel.

3. The adsorber according to claim 2, wherein At least one of the air outlets is provided on the housing corresponding to the channel.

4. The adsorber according to claim 3, wherein The channel corresponding to the air inlet is different from the channel corresponding to the air outlet.

5. The adsorber according to any one of claims 2 to 4, wherein: A partition is provided in the middle of the channel corresponding to the air inlet.

6. The adsorber according to any one of claims 1 to 5, wherein: The thickness of the adsorption bed is 1-20 cm.

7. The adsorber according to any one of claims 1 to 6, wherein: The thickness of the air flow distribution plate is 2-5 mm.

8. The adsorber according to any one of claims 1 to 7, wherein: The ratio of the aperture at the outlet of the airflow uniform distribution plate to the aperture at the inlet of the airflow uniform distribution plate is 1:(2-5).

9. The adsorber according to any one of claims 1 to 8, wherein: The ratio of the width of the channel to the thickness of the adsorption bed is 1:(2-10).

10. The adsorber according to any one of claims 1 to 9, wherein: A pressure monitoring gauge is also provided, and the pressure monitoring gauge is used to monitor the pressure of the first end surface and the second end surface of the adsorption bed layer which are arranged opposite to each other in the thickness direction.

11. The adsorber according to any one of claims 1 to 10, wherein: A temperature monitoring meter is also provided, and the temperature monitoring meter is used to monitor the temperature of a first end surface and a second end surface of the adsorption bed layer which are arranged opposite to each other in the thickness direction.

12. The adsorber according to any one of claims 1 to 11, wherein: The shell is also provided with a liquid outlet, which is used to discharge the condensed liquid in the adsorption bed.

13. The adsorber according to any one of claims 1 to 11, wherein: The outer side of the shell is also covered with a heat-insulating layer.

14. An adsorption method for an adsorber according to any one of claims 1 to 13, wherein: The following steps are involved: (1) The gas to be adsorbed is sent to the cavity in the adsorber through the air inlet, dispersed by the air flow distribution plate, and then enters the adsorption bed for adsorption treatment to obtain adsorbed gas and a saturated adsorption bed, and the adsorbed gas is extracted through the air outlet; (2) vacuuming the remaining gas in the adsorber until the pressure in the adsorber is -85 kPa to -95 kPa; (3) delivering the regenerated gas to the cavity in the adsorber through the air inlet, dispersing the gas through the air flow distribution plate, and regenerating the saturated adsorption bed to obtain desorbed gas, condensate, and a regenerated adsorption bed; the desorbed gas is extracted through the air outlet; (4) Cooling the regenerated adsorption bed.

15. The adsorption method according to claim 14, wherein When the gas to be adsorbed is air and the desorbed gas is carbon dioxide, the adsorption bed comprises an adsorbent, and the ratio of the mass of the adsorbent to the adsorption amount of the carbon dioxide is 0.9-2 mmol / g.

16. The adsorption method according to claim 14 or 15, wherein The particle size distribution of the adsorbent is 0.3 mm to 1.5 mm, and the adsorbent includes a solid amine adsorption material.

17. The adsorption method according to any one of claims 14 to 16, wherein: In step (1), the amount of gas to be adsorbed is 200-300 Nm 3 / h; the temperature of the adsorption treatment is 20-40°C and the time is 100-120min.

18. The adsorption method according to any one of claims 14 to 17, wherein: In step (3), the regeneration gas is water vapor, the temperature of the regeneration treatment is 80-120° C., and the time is 10-30 minutes; the regeneration treatment includes steam direct purge regeneration treatment.

19. An adsorption system, wherein: The adsorber comprises the adsorber according to any one of claims 1 to 13.

20. The adsorption system according to claim 19, wherein It also includes a gas purification and cooling device to be adsorbed, an adsorption device, a regeneration gas generating device, and a separation device; Wherein, the adsorption device comprises at least one adsorber; The outlet of the adsorbed gas purification cooling device is connected to the air inlet of the adsorber, and the air outlet of the adsorber is used to output the adsorbed gas; The outlet of the regeneration gas generating device is connected to the air inlet of the adsorber, and the air outlet of the adsorber is also connected to the inlet of the separation device. The gas phase outlet of the separation device is used to output product gas, and the liquid phase outlet of the separation device is connected to the reflux port of the regeneration gas generating device.

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