Carbon dioxide capture system in power plant boiler tail gas

Abstract

The present invention provides a system for capturing carbon dioxide in the tail gas of a power station boiler, including a zeolite storage chamber arranged in a chimney, the zeolite storage chamber is filled with zeolite, the top and bottom of the zeolite storage chamber are sealed, and air holes are arranged on the peripheral wall of the zeolite storage chamber; an output pipe is connected to the bottom of the zeolite storage chamber; a drum-type zeolite heater is arranged in the chimney, and the inlet of the drum-type zeolite heater is rotatably connected with an output pipe, the output pipe is connected to the bottom of the zeolite storage chamber, and the drum-type zeolite heater is also connected with a zeolite output pipe and a carbon dioxide outlet pipe, and the zeolite output pipe is sealed and connected to a zeolite storage bin; a zeolite lifting and conveying mechanism is arranged in the chimney, and the inlet of the zeolite lifting and conveying mechanism is connected to the zeolite storage bin, and the outlet of the zeolite lifting and conveying mechanism is connected to the zeolite storage chamber, and is used to deliver the zeolite stored in the zeolite storage bin into the zeolite storage chamber after lifting and conveying to adsorb carbon dioxide. The present invention uses zeolite to achieve low-cost carbon dioxide capture.

Description

Technical Field

[0001] The invention relates to the technical field of power station boiler tail gas recovery, in particular to a system for capturing carbon dioxide in power station boiler tail gas. Background Art

[0002] Since the Industrial Revolution, human energy activities have caused 2 Greenhouse gas emissions are the main cause of the intensification of the global greenhouse effect.

[0003] Carbon capture, commonly known as "CCSU", adds "utilization" to carbon dioxide capture and storage (CCS), separating carbon dioxide from the air or factory chimney exhaust and using or storing it several kilometers underground, thereby reducing carbon emissions in the atmosphere. Therefore, many energy and chemical companies have adopted CCUS as an important way to reduce carbon emissions.

[0004] Thermal power generation has always dominated the power supply in my country, and will continue to be the basis of my country's power supply for some time to come. Since the raw materials for thermal power generation are fossil fuels such as coal, oil, and natural gas, the combustion process releases a large amount of carbon dioxide. With the proposal of the "carbon peak and carbon neutrality" goals, thermal power plants are facing great pressure on carbon emissions.

[0005] Among the many carbon capture technology routes, separating carbon dioxide after combustion has the least impact on the existing operation mode of the coal-based energy system. Usually, when treating the tail flue gas, the carbon dioxide capture, recovery, purification and other units are relatively independent.

[0006] Post-combustion capture is the most mature method for capturing carbon dioxide. At present, the carbon dioxide gas generated by combustion is mainly captured by absorption, adsorption, membrane separation, etc. The absorption method includes chemical absorption and physical absorption. The chemical absorption method is to absorb carbon dioxide through a chemical absorbent, which reacts chemically with carbon dioxide to generate new substances for fixing carbon dioxide, thereby achieving the effect of adsorption and separation of carbon dioxide in the flue. However, the use of chemical absorbents in this method has problems of corrosiveness and oxidative degradation, and there are environmental hazards. The physical absorption method refers to the use of organic solvents as absorption liquids to absorb carbon dioxide under pressure without chemically reacting with carbon dioxide, thereby achieving the removal of carbon dioxide from flue gas. However, the physical absorption method is not very selective for carbon dioxide gas, which increases the processing cost. The principle of removing carbon dioxide by membrane separation is to use the higher rate of carbon dioxide passing through the membrane than other gases, so that the carbon dioxide gas passing through the membrane can be quickly absorbed by the chemical absorbent on the other side of the membrane. However, membrane separation has the disadvantage of high cost and limited application prospects. The adsorption method refers to a method of enriching carbon dioxide by selectively absorbing carbon dioxide molecules onto the surface of another material through weak van der Waals forces (physical adsorption) or strong covalent bonding forces (chemical adsorption). For example, zeolite can be used to selectively adsorb carbon dioxide gas in flue gas, but due to the limited adsorption capacity of zeolite and the continuous emission of gas in the flue, a certain amount of zeolite is difficult to meet the continuous adsorption of carbon dioxide in flue gas, so it is necessary to replace the zeolite in the chimney in time. However, when replacing the zeolite, the zeolite needs to be taken out of the chimney. However, the chimney is continuously exhausting gas, and then the device for replacing the zeolite is put into the chimney. It will take a certain amount of time in the middle, which will cause the gas during the replacement time to not be absorbed and be discharged into the atmosphere, causing air pollution. Summary of the invention

[0007] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a system for capturing carbon dioxide in power plant boiler exhaust gas, which connects the adsorption and desorption of carbon dioxide with the transportation of zeolite in the chimney to form a closed loop. Under the premise of recycling the zeolite, there is no need to take out the zeolite from the chimney for replacement, thereby solving the problem of environmental pollution caused by exhaust gas discharged into the atmosphere during zeolite replacement.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions: a system for capturing carbon dioxide in the tail gas of a power plant boiler, comprising a zeolite storage chamber arranged in a chimney, the zeolite storage chamber is filled with a plurality of zeolites that selectively adsorb carbon dioxide, the top and bottom of the zeolite storage chamber are sealed, and a plurality of air holes for carbon dioxide gas to enter are arranged on the peripheral wall of the zeolite storage chamber; an output pipe is connected to the bottom of the zeolite storage chamber;

[0009] A drum-type zeolite heater is used to remove carbon dioxide adsorbed by zeolite. The drum-type zeolite heater is arranged in the chimney, and the inlet of the drum-type zeolite heater is rotatably connected to an output pipe, the output pipe is connected to the bottom of the zeolite storage chamber, and the drum-type zeolite heater is also connected to a zeolite output pipe and a carbon dioxide outlet pipe, and the zeolite output pipe is sealed and connected to the zeolite storage bin;

[0010] The zeolite lifting and conveying mechanism is arranged in the chimney, and the inlet of the zeolite lifting and conveying mechanism is connected with the zeolite storage bin, and the outlet of the zeolite lifting and conveying mechanism is connected with the zeolite storage chamber, which is used to lift and convey the zeolite stored in the zeolite storage bin into the zeolite storage chamber to adsorb carbon dioxide.

[0011] Preferably, an opening and closing mechanism and four weight sensors are also provided inside the zeolite storage chamber, and the opening and closing mechanism includes an electronic control device, four baffles and an up and down reciprocating member; the four baffles are quarter-circular plate bodies that can form a circular plate after splicing, and the four baffles are rotatably connected to the inner wall of the zeolite storage chamber respectively, and a weight sensor is connected to the bottom of each baffle, and a pull rod is vertically provided at the bottom of each baffle, and the bottoms of the four pull rods are connected by a connecting frame, and the up and down reciprocating member is provided on the inner wall of the zeolite storage chamber, and the up and down reciprocating member is connected to the connecting frame, and the up and down reciprocating member and the weight sensor are electrically connected to the electronic control device, and the up and down reciprocating member is used to drive the connecting frame to move away from or close to the weight sensor in the vertical direction by judging the change in the weight of the zeolite detected by the weight sensor, so that the zeolite with the increased weight due to the absorption of carbon dioxide is discharged from the zeolite storage chamber, and the drum-type zeolite heating machine and the zeolite lifting and conveying mechanism are also electrically connected to the electronic control device.

[0012] Preferably, the up and down reciprocating parts include a forward and reverse motor, a threaded rod, a nut and a reducer, the forward and reverse motor is connected to the electronic control device, and the forward and reverse motor is vertically arranged on the inner wall of the zeolite storage chamber, and the rotating shaft of the forward and reverse motor is connected to the reducer, the threaded rod is connected to the reducer, the nut is threadedly connected to the threaded rod, and a fixing rod is connected to the nut, one end of the fixing rod is vertically slidably connected to a fixing plate, the fixing plate is vertically arranged in the zeolite storage chamber, and the other end of the fixing rod is connected to a connecting frame.

[0013] Preferably, the drum-type zeolite heating machine includes a rolling bin, which is a hollow cylinder. A zeolite inlet is provided on the rolling bin, which is rotatably connected to an output pipe. A zeolite output pipe connected to a carbon dioxide outlet pipe is also provided on the rolling bin away from the zeolite inlet, and a heating device is provided on the rolling bin.

[0014] Preferably, the rolling bin is made of metal.

[0015] Preferably, the heating device is a heating pipe wound around the outer wall of the rolling bin, the inlet of the heating pipe is connected to the hot flue gas conveying pipe, and the outlet of the heating pipe is connected to the boiler chimney.

[0016] Preferably, the zeolite storage chamber includes a steel structure frame, on which a steel mesh is wound, the mesh holes of the steel mesh are air holes, the opening and closing mechanism is arranged in the steel structure frame and connected to the inner wall of the steel structure frame, the top of the steel structure frame is connected to the zeolite lifting and conveying mechanism, and the bottom of the steel structure frame is connected to the output pipe.

[0017] Preferably, the steel structure frame is a dumbbell-shaped structure.

[0018] Preferably, the zeolite lifting and conveying mechanism comprises a vertical bucket elevator and a belt conveyor, the inlet of the vertical bucket elevator is connected to the zeolite storage bin, the outlet of the vertical bucket elevator is connected to the belt conveyor, and the belt conveyor is connected to the zeolite storage chamber.

[0019] Preferably, the carbon dioxide outlet pipe is in communication with an air separator.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention solves the problem that the zeolite storage chamber in the chimney needs to replace the zeolite after a certain period of adsorption, which causes the exhaust gas to be not absorbed during the zeolite replacement and discharged into the atmosphere, causing air pollution. The solution provided by the present invention is to connect the zeolite storage chamber, the drum-type zeolite heater and the zeolite lifting and conveying mechanism and place them in the chimney. At this time, the carbon dioxide gas in the chimney enters the zeolite storage chamber through the pores and is adsorbed by the zeolite. Since the top of the zeolite storage chamber is connected to the zeolite lifting and conveying mechanism, and the bottom of the zeolite storage chamber is connected to the drum-type zeolite heater, and the drum-type zeolite heater is connected to the zeolite lifting and conveying mechanism, the zeolite storage chamber, the drum-type zeolite heater and the zeolite lifting and conveying mechanism are connected in series as a whole. Therefore, the zeolite in the zeolite storage chamber is always in a flowing state. The zeolite in the flowing state can not only absorb the carbon dioxide gas entering the zeolite storage chamber through multiple pores, but also fall into the drum-type zeolite heater under the action of gravity, and the zeolite is desorbed by the drum-type zeolite heater, and the treated zeolite is sent back to the zeolite storage chamber through the zeolite lifting and conveying mechanism. This process is carried out continuously, and there is no need to take the zeolite storage chamber out of the chimney to replace the adsorbed zeolite, so it avoids the occurrence of air pollution caused by exhaust gas not being absorbed and discharged into the atmosphere during the zeolite replacement.

[0022] 2. The present invention utilizes a zeolite (the zeolite is zeolite X18) that selectively adsorbs carbon dioxide under low temperature (less than 200°C) conditions to adsorb a large amount of carbon dioxide emitted by power station boilers due to its strong adsorption capacity for carbon dioxide, thereby achieving low-cost carbon dioxide capture; the present invention connects the carbon dioxide adsorption devices to each other through a zeolite lifting and conveying device, forming a closed loop during the adsorption and desorption process of carbon dioxide, and the zeolite can be recycled, and there is no need to take the zeolite out of the chimney, resulting in the emission of waste gas into the atmosphere during replacement, causing environmental pollution. The entire carbon dioxide adsorption and desorption process is controlled in the chimney, which occupies a small space and has a compact process, reducing the equipment and labor costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the device for adsorbing carbon dioxide using zeolite X18 in the present invention;

[0024] Figure 2 It is a schematic diagram of the opening and closing structure of the carbon dioxide adsorption device in the present invention;

[0025] Figure 3 Schematic diagram of desorption of carbon dioxide by drum-type zeolite in the present invention;

[0026] Figure 4 This is a schematic diagram of the zeolite lifting and conveying structure in the present invention;

[0027] Figure 5 It is a schematic diagram of the overall structure of the carbon dioxide adsorption and desorption device in the present invention.

[0028] Description of reference numerals:

[0029] 1. Carbon dioxide adsorption device; 2. Zeolite X18; 3. Hot flue gas heating pipeline; 4. Output pipe; 5. Electronic control device; 6. Zeolite bucket elevator; 7. Carbon dioxide outlet pipeline; 8. Vertical bucket elevator; 9. Belt conveyor; 10. Baffle; 11. Drum zeolite heater; 12. Zeolite storage bin; 13. Opening and closing mechanism; 14. Weight sensor; 15. Motor; 16. Pull rod; 17. Threaded rod; 18. Nut; 19. Reducer. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] The inventors found that due to the CO2 The capture mainly adopts the absorption method, and the absorption method has high energy consumption for absorbent regeneration, pollutant emissions, absorbent oxidation degradation and corrosion problems. Therefore, in order to reduce the high energy consumption for absorbent regeneration, pollutant emissions, absorbent oxidation degradation and corrosion problems in the absorption method, in order to solve the above problems, zeolite can be used to selectively adsorb carbon dioxide gas in flue gas. However, due to the limited adsorption capacity of zeolite and the continuous emission of gas in the flue, a certain amount of zeolite is difficult to meet the continuous adsorption of carbon dioxide in the flue gas. Therefore, it is necessary to replace the zeolite in the chimney in time. However, when replacing the zeolite, the zeolite needs to be taken out of the chimney. However, the chimney is continuously exhausting gas, and then the device for replacing the zeolite is put into the chimney. It will take a certain amount of time, which will cause the gas within the replacement time to not be absorbed and discharged into the atmosphere to cause air pollution.

[0032] In view of this, the present invention connects the transport of zeolite for the absorption and desorption of carbon dioxide to each other in the chimney to form a closed loop. Under the premise of recycling the zeolite, there is no need to take out the zeolite from the chimney for replacement, thereby solving the problem of environmental pollution caused by exhaust gas discharge into the atmosphere during zeolite replacement.

[0033] The present invention provides a system for capturing carbon dioxide in the tail gas of a power plant boiler, such as Figure 1 to Figure 5 As shown, it comprises a zeolite storage chamber 1 arranged in the chimney, wherein the zeolite storage chamber 1 is filled with a plurality of zeolites 2 that selectively adsorb carbon dioxide, the top and bottom of the zeolite storage chamber 1 are sealed, and a plurality of air holes for carbon dioxide gas to enter are arranged on the peripheral wall of the zeolite storage chamber 1; an output pipe 4 is connected to the bottom of the zeolite storage chamber 1;

[0034] The drum-type zeolite heater 11 is used to remove the carbon dioxide adsorbed by the zeolite. The drum-type zeolite heater 11 is arranged in the chimney, and the inlet of the drum-type zeolite heater 11 is rotatably connected to an output pipe 4 through a bearing, and the output pipe 4 is connected to the bottom of the zeolite storage chamber 1. The drum-type zeolite heater 11 is also connected to a zeolite output pipe 6 and a carbon dioxide outlet pipe 7, and the zeolite output pipe 6 is sealed and connected to the zeolite storage bin 12; the drum-type zeolite heater 11 is also provided with an electric control device 5 for adjusting the rotation speed of the rolling bin, and the rotation speed of the drum-type zeolite heater 11 is controlled by the electric control device 5, thereby realizing the control of the amount of adsorption saturated zeolite X18 entering the drum-type zeolite heater 11, thereby ensuring that the zeolite entering the zeolite storage bin 12 is fully desorbed of CO 2 .

[0035] The zeolite lifting and conveying mechanism is arranged in the chimney, and the inlet of the zeolite lifting and conveying mechanism is connected with the zeolite storage bin 12, and the outlet of the zeolite lifting and conveying mechanism is connected with the zeolite storage chamber 1, which is used to lift and convey the zeolite stored in the zeolite storage bin 12 into the zeolite storage chamber 1 to adsorb carbon dioxide.

[0036] Before carbon dioxide adsorption and carbon dioxide desorption, it is necessary to first remove the large amount of SO generated during the operation of coal-fired power boilers. 2 , NOx, dust and ash are respectively introduced into the desulfurization system, denitrification system, slag removal system and electric bag dust removal system to remove SO 2 , NOx, ash and dust. At this time, the main components of the flue gas reaching the tail flue of the boiler are N 2 and CO 2 Mixed gas, N 2 and CO 2 The mixed gas enters the chimney through the exhaust flue between the boiler and the chimney. In order to avoid N 2 and CO 2 The mixed gas is discharged into the atmosphere to pollute the environment, so a zeolite storage chamber 1 containing carbon dioxide adsorbed is placed in the chimney to adsorb carbon dioxide. The zeolite X18 here adsorbs carbon dioxide by physical adsorption, which absorbs CO in the mixed gas. 2 will be selectively adsorbed in the pores of zeolite, and due to the fact that zeolite X18 2 It does not have selective adsorption function, so N 2 Emissions into the atmosphere through chimneys

[0037] Since the adsorption capacity of zeolite X18 is limited, the zeolite X18 that adsorbs carbon dioxide gas in the zeolite storage chamber 1 needs to be regenerated regularly to meet the absorption of carbon dioxide emitted from the chimney. After the zeolite X18 reaches its adsorption limit, it needs to be taken out of the chimney, replaced with zeolite X18, and adsorbed again. This process will cause harmful exhaust gas emissions into the atmosphere.

[0038] In order to solve the above problems, the present invention arranges a zeolite storage chamber 1 storing selective carbon dioxide zeolite X18, a drum-type zeolite heater 11 and a zeolite lifting and conveying mechanism in the chimney. By connecting the zeolite storage chamber 1, the drum-type zeolite heater 11 and the zeolite lifting and conveying mechanism to each other to form a closed loop, the zeolite X18 adsorbs carbon dioxide, the zeolite X18 adsorbed with carbon dioxide is desorbed, and the desorbed zeolite is sent back into the zeolite storage chamber 1 for adsorption.

[0039] When the zeolite is desorbed, the drum-type zeolite heater 11 is started. At this time, the zeolite X18 in the rolling bin of the drum-type zeolite heater 11 will move backward continuously with the rotation of the drum under the action of centrifugal force. While the rolling bin is rotating, the heating device located on the rolling bin (the heating device can be a heating plate or a heating tube) will heat the zeolite X18 in the rolling bin that has absorbed carbon dioxide. At this time, the carbon dioxide in the zeolite X18 that has absorbed carbon dioxide will escape from the pores of the zeolite X2 due to the heat, so that the carbon dioxide is separated from the zeolite X18, and the carbon dioxide is output from the carbon dioxide outlet pipe 7. The separated clean zeolite is sent to the zeolite storage bin 12, and then the clean zeolite 18 is transported to the zeolite storage chamber 1 through the zeolite lifting and conveying mechanism, completing the zeolite adsorption-desorption-re-conveying cycle.

[0040] Specifically, in order to solve the problem of low adsorption utilization of zeolite. An opening and closing mechanism 13 and four weight sensors 14 are also provided inside the zeolite storage chamber 1. The opening and closing mechanism 13 includes an electric control device 5, four baffles 10 and an up and down reciprocating member. The four baffles 10 are quarter-circular plates that can form a circular plate after splicing, and the four baffles 10 are rotatably connected to the inner wall of the zeolite storage chamber 1 respectively. A weight sensor 14 is connected to the bottom of each baffle 10, and a pull rod 16 is vertically provided at the bottom of each baffle 10. The bottoms of the four pull rods are connected by a connecting frame. The up and down reciprocating member is provided on the inner wall of the zeolite storage chamber 1, and the up and down reciprocating member is connected to the connecting frame. The up and down reciprocating member and the weight sensor 14 are electrically connected to the electric control device 5. The up and down reciprocating member is used to drive the connecting frame to move away from or close to the weight sensor 14 in the vertical direction by judging the change in the weight of the zeolite detected by the weight sensor 14, so that the zeolite with increased weight due to absorption of carbon dioxide is discharged from the zeolite storage chamber 1. The drum-type zeolite heating machine 11 and the zeolite lifting and conveying mechanism are also electrically connected to the electric control device 5. The up-and-down reciprocating member may be an electric push rod or other structure capable of performing the up-and-down reciprocating function.

[0041] When in use, by setting an opening and closing mechanism 13 and a weight sensor 14 in the zeolite storage chamber 1 located above the output pipe 4, the weight sensor 14 can be used to judge the change in the weight of the zeolite X18, so as to determine whether to open the opening and closing mechanism 13, thereby increasing the adsorption capacity and recycling rate of the zeolite X18.

[0042] The weight sensor 14 is used to determine the weight change of the zeolite X18. Generally, the weight of the zeolite X18 after adsorption is 110% of the weight of the zeolite X18 before adsorption.

[0043] When the weight threshold is reached, the weight sensor sends an electrical signal to the electronic control device, and the electronic control device 5 controls the motor 15 to start. After the motor 15 is decelerated by the gear of the reducer 19, it drives a pair of threaded rods 17 and nuts 18 to move downward along the fixed plate. Thus, the fixed rod drives the fixed frame to move downward, thereby causing the connecting rod to move downward, so that the four closed baffles are opened.

[0044] Specifically, the specific structure of the up and down reciprocating parts is given, and the up and down reciprocating parts include a forward and reverse motor 15, a threaded rod 17, a nut 18 and a reducer 19. The forward and reverse motor 15 is connected to the electronic control device 5, and the forward and reverse motor 15 is vertically arranged on the inner wall of the zeolite storage chamber 1, and the rotating shaft of the forward and reverse motor 15 is connected to the reducer 19, the threaded rod 17 is connected to the reducer 19, the nut 18 is threadedly connected to the threaded rod 17, and a fixing rod is connected to the nut 18, one end of the fixing rod is vertically slidably connected to a fixing plate, the fixing plate is vertically arranged in the zeolite storage chamber 1, and the other end of the fixing rod is connected to a connecting frame.

[0045] The purpose of selecting the up and down reciprocating parts of this structure here is to improve the smoothness of operation.

[0046] Specifically, the drum-type zeolite heating machine 11 includes a rolling bin, which is a hollow cylinder. A zeolite inlet is provided on the rolling bin, and the zeolite inlet is rotatably connected to the output pipe 4. A zeolite output pipe 6 connected to the carbon dioxide outlet pipe 7 is also provided on the rolling bin away from the zeolite inlet, and a heating device is provided on the rolling bin.

[0047] Specifically, the rolling bin is made of metal material to improve heat transfer efficiency.

[0048] Specifically, in order to improve energy utilization, the heating device is a heating pipe wound around the outer wall of the rolling bin, the inlet of the heating pipe is connected to the hot flue gas delivery pipe, and the outlet of the heating pipe is connected to the boiler chimney. In order to increase the contact surface between the heating pipe 3 and the rolling bin, the heating pipe 3 is a serpentine pipe.

[0049] Specifically, in order to improve the adsorption capacity of zeolite X18 in the zeolite storage chamber 1, the zeolite storage chamber 1 includes a steel structure frame, a steel mesh is wrapped on the steel structure frame, and the mesh holes of the steel mesh are air holes. The opening and closing mechanism 13 is arranged in the steel structure frame and connected to the inner wall of the steel structure frame. The top of the steel structure frame is connected to the zeolite lifting and conveying mechanism, and the bottom of the steel structure frame is connected to the output pipe 4.

[0050] Specifically, the steel structure frame is a dumbbell-shaped structure, the inner diameter of which is larger at both ends and smaller in the middle, so that the carbon dioxide gas enters the zeolite storage chamber 1 quickly and diffuses to both ends, resulting in more complete adsorption.

[0051] Specifically, the specific structure of the zeolite lifting and conveying mechanism is given, and the zeolite lifting and conveying mechanism includes a vertical bucket elevator 8 and a belt conveyor 9, the inlet of the vertical bucket elevator 8 is connected to the zeolite storage bin 12, the outlet of the vertical bucket elevator 8 is connected to the belt conveyor 9, and the belt conveyor 9 is connected to the zeolite storage chamber 1.

[0052] Specifically, the carbon dioxide outlet pipe 7 is communicated with the air separator.

[0053] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A system for capturing carbon dioxide in tail gas from a power plant boiler, comprising a zeolite storage chamber (1) arranged in a chimney, wherein the zeolite storage chamber (1) is filled with a plurality of zeolites (2) that selectively adsorb carbon dioxide, and wherein: The top and bottom of the zeolite storage chamber (1) are sealed, and a plurality of air holes for carbon dioxide gas to enter are provided on the peripheral wall of the zeolite storage chamber (1); the bottom of the zeolite storage chamber (1) is connected to an output pipe (4); A drum-type zeolite heater (11) is used to remove carbon dioxide adsorbed by zeolite. The drum-type zeolite heater (11) is arranged in a chimney, and an inlet of the drum-type zeolite heater (11) is rotatably connected to an output pipe (4), the output pipe (4) being connected to the bottom of the zeolite storage chamber (1). The drum-type zeolite heater (11) is also connected to a zeolite output pipe (6) and a carbon dioxide outlet pipe (7), and the zeolite output pipe (6) is sealed and connected to a zeolite storage bin (12); A zeolite lifting and conveying mechanism is arranged in the chimney, and the inlet of the zeolite lifting and conveying mechanism is connected to the zeolite storage bin (12), and the outlet of the zeolite lifting and conveying mechanism is connected to the zeolite storage chamber (1), and is used to lift and convey the zeolite stored in the zeolite storage bin (12) into the zeolite storage chamber (1) to adsorb carbon dioxide; The zeolite storage chamber (1) is also provided with an opening and closing mechanism (13) and four weight sensors (14). The opening and closing mechanism (13) comprises an electric control device (5), four baffles (10) and an upper and lower reciprocating member. The four baffles (10) are quarter-circular plates that can be assembled to form a circular plate. The four baffles (10) are rotatably connected to the inner wall of the zeolite storage chamber (1). The bottom of each baffle (10) is connected to a weight sensor (14). A pull rod (16) is vertically provided at the bottom of each baffle (10). The bottoms of the four pull rods are connected by a connecting frame. The up-and-down reciprocating member is arranged on the inner wall of the zeolite storage chamber (1), and is connected to the connecting frame. The up-and-down reciprocating member and the weight sensor (14) are electrically connected to the electric control device (5). The up-and-down reciprocating member is used to drive the connecting frame to move away from or toward the weight sensor (14) in the vertical direction by judging the change of the zeolite weight detected by the weight sensor (14), so that the zeolite with increased weight due to absorption of carbon dioxide is discharged from the zeolite storage chamber (1). The drum-type zeolite heating machine (11) and the zeolite lifting and conveying mechanism are also electrically connected to the electric control device (5).

2. The system for capturing carbon dioxide in power plant boiler tail gas according to claim 1, characterized in that: The up-and-down reciprocating member comprises a forward and reverse motor (15), a threaded rod (17), a nut (18) and a reducer (19); the forward and reverse motor (15) is connected to the electric control device (5), and the forward and reverse motor (15) is arranged vertically on the inner wall of the zeolite storage chamber (1), and the rotating shaft of the forward and reverse motor (15) is connected to the reducer (19); the threaded rod (17) is connected to the reducer (19), the nut (18) is threadedly connected to the threaded rod (17), and a fixing rod is connected to the nut (18), one end of the fixing rod is slidably connected to a fixing plate in the vertical direction, the fixing plate is arranged vertically in the zeolite storage chamber (1), and the other end of the fixing rod is connected to a connecting frame.

3. The system for capturing carbon dioxide in power plant boiler tail gas according to claim 1, characterized in that: The drum-type zeolite heating machine (11) comprises a rolling chamber, which is a hollow cylinder. A zeolite inlet is provided on the rolling chamber, which is rotatably connected to an output pipe (4). A zeolite output pipe (6) is also provided on the rolling chamber away from the zeolite inlet, which is connected to a carbon dioxide outlet pipe (7). A heating device is provided on the rolling chamber.

4. The system for capturing carbon dioxide in power plant boiler tail gas according to claim 3, characterized in that: The rolling bin is made of metal material.

5. The system for capturing carbon dioxide in power plant boiler tail gas according to claim 4, characterized in that: The heating device is a heating pipe (3) wound around the outer wall of the rolling bin, the inlet of the heating pipe (3) is connected to the hot flue gas conveying pipe, and the outlet of the heating pipe is connected to the boiler chimney.

6. The system for capturing carbon dioxide in power plant boiler tail gas according to claim 1, characterized in that: The zeolite storage chamber (1) comprises a steel structure frame, a steel mesh is wound around the steel structure frame, the mesh holes of the steel mesh are air holes, the opening and closing mechanism (13) is arranged in the steel structure frame and connected to the inner wall of the steel structure frame, the top of the steel structure frame is connected to the zeolite lifting and conveying mechanism, and the bottom of the steel structure frame is connected to the output pipe (4).

7. The system for capturing carbon dioxide in power plant boiler tail gas according to claim 6, characterized in that: The steel structure frame is a dumbbell-shaped structure.

8. The system for capturing carbon dioxide in power plant boiler tail gas according to claim 1, characterized in that: The zeolite lifting and conveying mechanism comprises a vertical bucket elevator (8) and a belt conveyor (9), the inlet of the vertical bucket elevator (8) is connected to the zeolite storage bin (12), the outlet of the vertical bucket elevator (8) is connected to the belt conveyor (9), and the belt conveyor (9) is connected to the zeolite storage chamber (1).

9. The system for capturing carbon dioxide in power plant boiler tail gas according to claim 1, characterized in that: The carbon dioxide outlet pipeline (7) is in communication with the air separator.

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