Sodium silicate kiln flue gas carbon dioxide trapping and recycling device and recycling method thereof

Abstract

The invention discloses a sodium silicate kiln flue gas carbon dioxide capturing and recycling device and a recycling method thereof, and relates to the technical field of sodium silicate kiln carbon dioxide recycling.The sodium silicate kiln flue gas carbon dioxide capturing and recycling device comprises a bottom plate, a tower base is installed at the upper end of the bottom plate, and a first electric control three-way valve is installed on one side of the tower base; a valve control mechanism is mounted at the upper end of the tower base, a plurality of trapping and recycling sections are mounted at the upper end of the valve control mechanism, the trapping and recycling sections are connected in series, and an observation window is mounted at the front end of each trapping and recycling section. The carbon dioxide is chemically absorbed in a countercurrent contact mode of the amine solution and the gas, but the amine solution is poor in high-temperature adaptability, and the adsorption capacity is easy to fade quickly through high-temperature volatilization.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon dioxide recovery from sodium silicate kilns, and in particular to a device for capturing and recovering carbon dioxide from flue gas in sodium silicate kilns and a recovery method thereof. Background Art

[0002] The combustion process of existing sodium silicate kilns produces high concentrations of carbon dioxide. In order to recover the carbon dioxide, the wet absorption method is currently mainly used to absorb the carbon dioxide in the flue gas; For example, announcement number CN202410501U, titled "A device for absorbing and producing carbon dioxide using an alcoholamine method," provides a device for absorbing and producing carbon dioxide using an alcoholamine method, comprising a cooling tower, a fan, an absorption tower, a rich liquid pump, a first cooler, a container, a regeneration tower, a lean liquid pump, a second cooler, a third cooler, a reboiler, a separator, an underground tank, an alcoholamine recovery heater, and a filter. The existing wet adsorption method uses a top-down spraying of amine solution to chemically absorb carbon dioxide, allowing the amine solution to contact the gas in countercurrent. However, the amine solution has poor high-temperature adaptability and its adsorption capacity tends to decay rapidly due to high-temperature volatilization. To this end, we provide a sodium silicate kiln flue gas carbon dioxide capture and recovery device and a recovery method. Summary of the Invention

[0003] The object of the present invention is to provide a device for capturing and recovering carbon dioxide from flue gas of a sodium silicate kiln and a recovery method thereof, so as to solve the problem proposed in the above-mentioned background art that the existing wet adsorption method adopts a top-down spraying of an amine solution so that the amine solution and the gas are in countercurrent contact to chemically absorb carbon dioxide, but the amine solution has poor high-temperature adaptability and is prone to rapid attenuation of the adsorption capacity due to high-temperature volatilization.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a device for capturing and recovering carbon dioxide from flue gas in a sodium silicate kiln, comprising a base plate, a tower base being installed at the upper end of the base plate, a first electrically controlled three-way valve being installed on one side of the tower base, a valve control mechanism being installed at the upper end of the tower base, a capture and recovery section being installed at the upper end of the valve control mechanism, a plurality of capture and recovery sections being provided, and the plurality of capture and recovery sections being connected in series, an observation window being installed at the front end of the capture and recovery section, a smoke exhaust hood being installed at the upper end of the capture and recovery section, a second electrically controlled three-way valve being installed at the upper end of the smoke exhaust hood, and an amine solution-modified zeolite filler being installed inside the capture and recovery section.

[0005] Preferably, the amine solution modified zeolite filler is prepared by impregnating porous zeolite with amine solution for modification.

[0006] Preferably, a sodium silicate fume supply pipe is installed at the rear end of the first electrically controlled three-way valve, and a fume exhaust pipe is installed at the rear end of the second electrically controlled three-way valve.

[0007] Preferably, a plurality of heat exchange mechanisms are installed inside the sodium silicate flue gas supply pipe, and the plurality of heat exchange mechanisms are connected in series. A spiral heat exchange tube is installed inside the heat exchange mechanism, and both ends of the spiral heat exchange tube pass through and extend to the outside of the heat exchange mechanism and are connected to the circulating water cooler. A temperature flow sensor is installed at the front section of the sodium silicate flue gas supply pipe, and a temperature sensor is installed at the rear section of the sodium silicate flue gas supply pipe.

[0008] Preferably, a rich liquid supply pipe is installed at the front end of the first electrically controlled three-way valve, and a desorption gas recovery pipe is installed at the front end of the second electrically controlled three-way valve.

[0009] Preferably, the valve control mechanism includes a valve seat, the upper and lower ends of the valve seat are respectively connected to the tower base and the capture and recovery section flange through flanges, valve plate storage bins are installed on both sides of the valve seat, valve plates are provided on both sides of the interior of the valve seat, and a hydraulic cylinder is installed at the end of the valve plate storage bin, and the output end of the hydraulic cylinder passes through and extends to the interior of the valve plate storage bin, and is transmission-connected to the valve plate.

[0010] Preferably, the lower parts of both sides of the valve plate storage bin are connected to the bottom plate through support frames.

[0011] Preferably, a drain valve is installed at the rear end of the tower base, a liquid supply pump is provided behind the drain valve, a liquid supply pipe is installed at the output end of the liquid supply pump, and one end of the liquid supply pipe is connected to the smoke exhaust hood.

[0012] Preferably, a one-way valve is installed inside the liquid supply pipe.

[0013] Preferably, a recovery method of a sodium silicate kiln flue gas carbon dioxide capture and recovery device comprises the following steps: Step 1: First, switch the first electrically controlled three-way valve to the sodium silicate flue gas supply pipe, and switch the second electrically controlled three-way valve to the exhaust pipe. At this time, the tower body operates as an absorption tower; Step 2: The flue gas is concentratedly introduced into the dust removal pretreatment module through the kiln exhaust pipe to remove particulate matter in the flue gas; Step 3: The pre-filtered flue gas enters the sodium silicate flue gas inlet pipe from the exhaust port of the dust removal pretreatment module. The temperature flow sensor in the front section of the sodium silicate flue gas inlet pipe performs pre-detection of the flue gas flow rate and temperature. Based on the real-time changes in the inlet temperature and flow rate, the number of operating heat exchange mechanisms is adjusted in advance to control the temperature at 40-50°C. The temperature sensor in the rear section can further confirm the outlet temperature. If the temperature still exceeds the threshold, a feedback signal is sent to the circulating water chiller to increase the cooling water flow rate to further improve the heat exchange efficiency. Step 4: The flue gas after heat exchange enters the tower base and passes through multiple capture and recovery sections above the tower base in sequence. Each capture and recovery section is equipped with an amine solution-modified zeolite filler. The amine solution-modified zeolite filler captures and recovers carbon dioxide in the flue gas based on the physical adsorption of zeolite and the chemical absorption of amine solution, obtaining a rich liquid after absorbing CO2; Step 5: The flue gas that has absorbed carbon dioxide is discharged from the exhaust pipe; Step 6: After an adsorption cycle is completed, the first electrically controlled three-way valve is switched to the rich liquid supply pipe passage, and the second electrically controlled three-way valve is switched to the desorption gas recovery pipe passage; steam heated to 100-120° C. is transported into the tower through the rich liquid supply pipe, so that the rich liquid enriched in the amine solution modified zeolite filler (501) releases carbon dioxide under the indirect heating effect of the high-temperature steam, and the desorbed carbon dioxide is recovered through the desorption gas recovery pipe; Step 7: The analyzed carbon dioxide enters the condenser through the gas recovery pipe to separate the water and obtain high-purity carbon dioxide; Step 8: During the desorption stage, amine molecules that are not tightly bound to the amine solution-modified zeolite packing will escape from the zeolite pores under the indirect heating of high-temperature steam. In order to ensure the efficient adsorption effect of the amine solution-modified zeolite packing, the amine solution-modified zeolite packing is reactivated every three months. During reactivation, the valve control mechanism at the connection between the tower base and the capture and recovery section is first driven to control the hydraulic cylinders on both sides of the valve control mechanism to extend, so that the valve plates in the valve plate storage bins on both sides move closer to the center, thereby achieving the closure of the capture and recovery section. Afterwards, the amine solution is supplied to the capture and recovery section by the liquid supply pump, so that the amine solution submerges the amine solution-modified zeolite packing. Under the action of physical impregnation, the amine solution adheres to the zeolite pores through physical adsorption and capillary action, thereby reactivating the amine solution-modified zeolite packing.

[0014] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention captures and recovers carbon dioxide in the flue gas of the sodium silicate kiln by adopting a multi-stage capture and recovery section. The multi-stage capture and recovery section contains an amine solution modified zeolite filler. The amine solution modified zeolite filler is made by impregnating porous zeolite with amine solution. The porous structure of the zeolite can fix the amine solution. As a carrier of the amine solution, the carbon dioxide can be better absorbed by the amine solution, reducing the volatilization loss at high temperature. At the same time, the zeolite itself has good temperature resistance and can withstand 200-300℃, which can adapt to the high temperature environment of the flue gas of the sodium silicate kiln. During the capture process, it is only necessary to ensure that the flue gas temperature is 40-50℃. During the process, the amine solution modified zeolite filler can efficiently capture and recover carbon dioxide in the flue gas based on the physical adsorption of the zeolite and the chemical absorption of the amine solution, thereby solving the problems that the existing wet adsorption materials have poor adaptability to high-temperature flue gas, the adsorption capacity decays quickly, and the temperature needs to be controlled at low temperature by a multi-stage cooling mechanism to absorb carbon dioxide, and the processing process is cumbersome.

[0015] (2) During the operation of the present invention, after an adsorption cycle is completed, the first electrically controlled three-way valve is switched to the rich liquid supply pipe passage, and the second electrically controlled three-way valve is switched to the desorption gas recovery pipe passage. At this time, the tower body operates as a desorption tower, and steam heated to 100-120°C can be directly transported into the tower by the rich liquid supply pipe, so that the rich liquid enriched in the amine solution modified zeolite filler releases carbon dioxide under the indirect heating effect of the high-temperature steam, and the desorbed carbon dioxide is recovered through the desorption gas recovery pipe, and the conversion between capture and desorption is directly completed in a single tower, which is efficient and fast.

[0016] (3) In the desorption stage of the present invention, in order to ensure the efficient adsorption effect of the amine solution modified zeolite filler, the amine solution modified zeolite filler is reactivated once every three months. During the reactivation, the valve control mechanism at the connection between the tower base and the capture and recovery section is first driven to control the hydraulic cylinders on both sides of the valve control mechanism to extend, so that the valve plates in the valve plate storage bins on both sides move closer to the center, thereby achieving the closure of the capture and recovery section, thereby greatly reducing the subsequent supply of amine solution. After that, the amine solution is supplied to the capture and recovery section by the liquid supply pump, so that the amine solution submerges the amine solution modified zeolite filler. Under the action of physical impregnation, the amine solution is attached to the pores of the zeolite through physical adsorption and capillary action, thereby reactivating the amine solution modified zeolite filler to ensure the efficient operation of the device.

[0017] (4) In the pre-treatment of the present invention, the dust removal pre-treatment module first removes the particulate matter in the flue gas to ensure the service life of the amine solution modified zeolite filler. The flue gas filtered by the pre-treatment enters the sodium silicate flue gas supply pipe from the exhaust port of the dust removal pre-treatment module. The temperature flow sensor of the front section of the sodium silicate flue gas supply pipe performs pre-detection of the flow rate and temperature of the flue gas. According to the real-time changes of the inlet temperature and flow rate, the operation quantity of the heat exchange mechanism is adjusted in advance to control the temperature at 40-50°C. The temperature sensor located in the rear section can To further confirm the outlet temperature, if the temperature still exceeds the threshold, a feedback signal is sent to the circulating water chiller to increase the cooling water flow rate to further improve the heat exchange efficiency, thereby ensuring that the flue gas temperature in the tower is 40-50°C. At low temperatures, the absorption exothermic reaction is promoted in a positive direction, thereby increasing the CO2 absorption capacity; at low temperatures, the viscosity of the amine solution is reduced, gas-liquid mass transfer is accelerated, and CO2 is more easily transferred from the gas phase to the deep liquid phase; at low temperatures, the oxidation and volatilization of the amine solution are reduced, reducing consumption; at the same time, a temperature gradient is formed in synergy with high-temperature regeneration to minimize global energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the back structure of the present invention; Figure 3Schematic diagram of the valve control mechanism structure of the present invention; Figure 4 This is a schematic diagram of the internal structure of the capture and recovery section of the present invention; Figure 5 Schematic diagram of the internal structure of the heat exchange mechanism of the present invention; In the figure: 1. Base plate; 2. Tower base; 3. Valve control mechanism; 301. Valve seat; 302. Flange; 303. Valve plate; 304. Valve plate storage compartment; 305. Hydraulic cylinder; 4. Support frame; 5. Capture and recovery section; 501. Amine solution modified zeolite filler; 6. Observation window; 7. Smoke exhaust hood; 8. First electrically controlled three-way valve; 9. Rich liquid supply pipe; 10. Sodium silicate flue gas supply pipe; 11. Heat exchange mechanism; 111. Spiral heat exchange tube; 12. Temperature sensor; 13. Second electrically controlled three-way valve; 14. Smoke exhaust pipe; 15. Desorption gas recovery pipe; 16. Drain valve; 17. Liquid supply pump; 18. Liquid supply pipe; 19. One-way valve. DETAILED DESCRIPTION

[0019] 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, rather than all the embodiments.

[0020] See also Figure 1-5 The present invention provides an embodiment: a sodium silicate kiln flue gas carbon dioxide capture and recovery device, comprising a base plate 1, a tower base 2 is installed on the upper end of the base plate 1, a first electrically controlled three-way valve 8 is installed on one side of the tower base 2, a valve control mechanism 3 is installed on the upper end of the tower base 2, a capture and recovery section 5 is installed on the upper end of the valve control mechanism 3, a plurality of capture and recovery sections 5 are provided, and the plurality of capture and recovery sections 5 are connected in series, an observation window 6 is installed at the front end of the capture and recovery section 5, a smoke exhaust hood 7 is installed on the upper end of the end capture and recovery section 5, a second electrically controlled three-way valve 13 is installed on the upper end of the smoke exhaust hood 7, and an amine solution-modified zeolite filler 501 is installed inside the capture and recovery section 5.

[0021] Furthermore, the amine solution modified zeolite filler 501 is made by impregnating porous zeolite with amine solution. The porous structure of the zeolite can fix the amine solution. As a carrier of the amine solution, it can better absorb carbon dioxide by the amine solution and reduce volatilization loss at high temperatures. At the same time, the zeolite itself has good temperature resistance and can withstand 200-300°C, which can adapt to the high temperature environment of sodium silicate kiln flue gas.

[0022] See also Figure 1The rear end of the first electrically controlled three-way valve 8 is installed with a sodium silicate flue gas supply pipe 10, and the rear end of the second electrically controlled three-way valve 13 is installed with a smoke exhaust pipe 14. When capturing carbon dioxide, the first electrically controlled three-way valve 8 is first switched to the sodium silicate flue gas supply pipe 10 passage, and the second electrically controlled three-way valve 13 is switched to the smoke exhaust pipe 14 passage, so that the flue gas enters the capture and recovery section 5 to capture carbon dioxide.

[0023] See also Figure 1 and Figure 5 The interior of the sodium silicate flue gas supply pipe 10 is equipped with a plurality of heat exchange mechanisms 11, and the plurality of heat exchange mechanisms 11 are connected in series. A spiral heat exchange tube 111 is installed inside the heat exchange mechanism 11. Both ends of the spiral heat exchange tube 111 pass through and extend to the outside of the heat exchange mechanism 11 and are connected to the circulating water cooler. The front section of the sodium silicate flue gas supply pipe 10 is equipped with a temperature flow sensor, and the rear section of the sodium silicate flue gas supply pipe 10 is equipped with a temperature sensor 12. After the flue gas enters the sodium silicate flue gas supply pipe 10, the temperature of the front section of the sodium silicate flue gas supply pipe 10 is first measured by the temperature of the front section of the sodium silicate flue gas supply pipe 10. The flow sensor performs pre-detection on the flow rate and temperature of the flue gas, and adjusts the operating quantity of the heat exchange mechanism 11 in advance according to the real-time changes in the inlet temperature and flow rate. When the flue gas passes through the heat exchange mechanism 11, the circulating water chiller supplies cooling water into the spiral heat exchange tube 111 in the heat exchange mechanism 11 to cool the flue gas. The multi-stage coordinated cooperation controls the temperature at 40-50°C, and the temperature sensor 12 located in the rear section can further confirm the outlet temperature. If the temperature still exceeds the threshold, the feedback signal is sent to the circulating water chiller to increase the cooling water flow rate to further improve the heat exchange efficiency.

[0024] See also Figure 1 A rich liquid supply pipe 9 is installed at the front end of the first electrically controlled three-way valve 8, and a desorption gas recovery pipe 15 is installed at the front end of the second electrically controlled three-way valve 13. When an adsorption cycle is completed, the first electrically controlled three-way valve 8 switches to the rich liquid supply pipe 9 passage, and the second electrically controlled three-way valve 13 switches to the desorption gas recovery pipe 15 passage, introducing high-temperature steam to desorb carbon dioxide.

[0025] See also Figure 1 and Figure 3 The valve control mechanism 3 includes a valve seat 301. The upper and lower ends of the valve seat 301 are flange-connected to the tower base 2 and the capture and recovery section 5 through flanges 302 respectively. Valve plate storage compartments 304 are installed on both sides of the valve seat 301. Valve plates 303 are provided on both sides of the interior of the valve seat 301. A hydraulic cylinder 305 is installed at the end of the valve plate storage compartment 304. The output end of the hydraulic cylinder 305 passes through and extends to the interior of the valve plate storage compartment 304 and is transmission-connected to the valve plate 303. When the amine solution-modified zeolite filler 501 needs to be re-energized, the valve control mechanism 3 can be closed to place the capture and recovery section 5 in a closed space, thereby significantly reducing the supply amount of amine solution.

[0026] See also Figure 1 The lower parts of both sides of the valve plate storage bin 304 are connected to the bottom plate 1 through the support frame 4.

[0027] See also Figure 2 A drain valve 16 is installed at the rear end of the tower base 2, and a liquid supply pump 17 is provided behind the drain valve 16. A liquid supply pipe 18 is installed at the output end of the liquid supply pump 17, and one end of the liquid supply pipe 18 is connected to the smoke exhaust hood 7. A one-way valve 19 is installed inside the liquid supply pipe 18. The liquid supply pump 17 supplies the amine solution into the capture and recovery section 5, so that the amine solution submerges the amine solution modified zeolite filler 501. Under the action of physical impregnation, the amine solution adheres to the pores of the zeolite through physical adsorption and capillary action, thereby restoring the amine solution modified zeolite filler 501. The one-way valve 19 on the liquid supply pipe 18 can prevent the flue gas from flowing back during the capture process.

[0028] See also Figure 1-5 A method for recovering carbon dioxide from sodium silicate kiln flue gas using a device for capturing and recovering carbon dioxide comprises the following steps: Step 1: First, switch the first electrically controlled three-way valve 8 to the sodium silicate flue gas supply pipe 10, and switch the second electrically controlled three-way valve 13 to the exhaust pipe 14. At this time, the tower body operates as an absorption tower; Step 2: The flue gas is centrally introduced into the dust removal pretreatment module through the kiln exhaust pipe to remove particulate matter in the flue gas to ensure the service life of the amine solution modified zeolite filler 501; Step 3: The pre-filtered flue gas enters the sodium silicate flue gas inlet pipe 10 from the exhaust port of the dust removal pretreatment module. The temperature flow sensor in the front section of the sodium silicate flue gas inlet pipe 10 performs pre-detection of the flue gas flow rate and temperature. Based on the real-time changes in the inlet temperature and flow rate, the operation frequency of the heat exchange mechanism 11 is adjusted in advance to control the temperature at 40-50°C. The temperature sensor 12 in the rear section can further confirm the outlet temperature. If the temperature still exceeds the threshold, a feedback signal is sent to the circulating water chiller to increase the cooling water flow rate to further improve the heat exchange efficiency. Step 4: The flue gas after heat exchange enters the tower base 2 and sequentially passes through multiple capture and recovery sections 5 above the tower base 2. Each capture and recovery section 5 is equipped with an amine solution-modified zeolite filler 501. The amine solution-modified zeolite filler 501 captures and recovers carbon dioxide in the flue gas based on physical adsorption of the zeolite and chemical absorption of the amine solution, obtaining a rich liquid after absorbing CO2. Step 5: The flue gas that has absorbed carbon dioxide is discharged from the exhaust pipe 14; Step 6: After an adsorption cycle (approximately 10-24 hours) is completed, the first electrically controlled three-way valve 8 switches to allow passage through the rich liquid supply pipe 9, and the second electrically controlled three-way valve 13 switches to allow passage through the desorption gas recovery pipe 15. At this point, the tower operates as a desorption tower. Steam heated to 100-120°C is delivered into the tower via the rich liquid supply pipe 9, causing the rich liquid accumulated in the amine solution-modified zeolite packing 501 to release carbon dioxide under the indirect heating effect of the high-temperature steam. The desorbed carbon dioxide is then recovered through the desorption gas recovery pipe 15. Step 7: The analyzed carbon dioxide enters the condenser through the gas recovery pipe 15 to separate the water to obtain high-purity carbon dioxide (> 99%); Step 8: During the desorption stage, in order to ensure the efficient adsorption effect of the amine solution-modified zeolite filler 501, the amine solution-modified zeolite filler 501 is reactivated once every three months. During reactivation, the valve control mechanism 3 at the connection between the tower base 2 and the capture and recovery section 5 is first driven to control the hydraulic cylinders 305 on both sides of the valve control mechanism 3 to extend, so that the valve plates 303 in the valve plate storage bins 304 on both sides are moved closer to the center, thereby achieving the closure of the capture and recovery section 5. Then, the amine solution is supplied into the capture and recovery section 5 by the liquid supply pump 17, so that the amine solution submerges the amine solution-modified zeolite filler 501. Under the action of physical impregnation, the amine solution adheres to the pores of the zeolite through physical adsorption and capillary action, thereby reactivating the amine solution-modified zeolite filler 501.

[0029] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A device for capturing and recovering carbon dioxide from flue gas of a sodium silicate kiln, comprising a bottom plate (1), characterized in that: A tower base (2) is installed at the upper end of the base plate (1), a first electrically controlled three-way valve (8) is installed on one side of the tower base (2), a valve control mechanism (3) is installed at the upper end of the tower base (2), a capture and recovery section (5) is installed at the upper end of the valve control mechanism (3), a plurality of capture and recovery sections (5) are provided, and the plurality of capture and recovery sections (5) are connected in series, an observation window (6) is installed at the front end of the capture and recovery section (5), a smoke exhaust hood (7) is installed at the upper end of the capture and recovery section (5), a second electrically controlled three-way valve (13) is installed at the upper end of the smoke exhaust hood (7), and an amine solution-modified zeolite filler (501) is installed inside the capture and recovery section (5).

2. The device for capturing and recovering carbon dioxide from sodium silicate kiln flue gas according to claim 1, characterized in that: The amine solution modified zeolite filler (501) is made by impregnating porous zeolite with amine solution for modification.

3. The device for capturing and recovering carbon dioxide from sodium silicate kiln flue gas according to claim 2, characterized in that: A sodium silicate fume supply pipe (10) is installed at the rear end of the first electrically controlled three-way valve (8), and a fume exhaust pipe (14) is installed at the rear end of the second electrically controlled three-way valve (13).

4. The device for capturing and recovering carbon dioxide from flue gas of a sodium silicate kiln according to claim 3, characterized in that: A plurality of heat exchange mechanisms (11) are installed inside the sodium silicate flue gas supply pipe (10), and the plurality of heat exchange mechanisms (11) are connected in series. A spiral heat exchange pipe (111) is installed inside the heat exchange mechanism (11), and both ends of the spiral heat exchange pipe (111) pass through and extend to the outside of the heat exchange mechanism (11), and are connected to a circulating water cooler. A temperature flow sensor is installed at the front section of the sodium silicate flue gas supply pipe (10), and a temperature sensor (12) is installed at the rear section of the sodium silicate flue gas supply pipe (10).

5. The device for capturing and recovering carbon dioxide from flue gas of a sodium silicate kiln according to claim 4, characterized in that: A rich liquid supply pipe (9) is installed at the front end of the first electrically controlled three-way valve (8), and a desorption gas recovery pipe (15) is installed at the front end of the second electrically controlled three-way valve (13).

6. The device for capturing and recovering carbon dioxide from flue gas of a sodium silicate kiln according to claim 5, characterized in that: The valve control mechanism (3) includes a valve seat (301), the upper end and the lower end of the valve seat (301) are flange-connected to the tower base (2) and the capture recovery section (5) through flanges (302), valve plate storage bins (304) are installed on both sides of the valve seat (301), valve plates (303) are provided on both sides of the interior of the valve seat (301), and a hydraulic cylinder (305) is installed at the end of the valve plate storage bin (304), and the output end of the hydraulic cylinder (305) passes through and extends to the interior of the valve plate storage bin (304), and is transmission-connected to the valve plate (303).

7. The device for capturing and recovering carbon dioxide from flue gas of a sodium silicate kiln according to claim 6, characterized in that: The lower sides of the valve plate storage compartment (304) are connected to the bottom plate (1) via support frames (4).

8. The device for capturing and recovering carbon dioxide from flue gas of a sodium silicate kiln according to claim 7, characterized in that: A liquid discharge valve (16) is installed at the rear end of the tower base (2), a liquid supply pump (17) is provided behind the liquid discharge valve (16), a liquid supply pipe (18) is installed at the output end of the liquid supply pump (17), and one end of the liquid supply pipe (18) is connected to the smoke exhaust hood (7).

9. The device for capturing and recovering carbon dioxide from flue gas of a sodium silicate kiln according to claim 8, characterized in that: A one-way valve (19) is installed inside the liquid supply pipe (18).

10. A method for recovering carbon dioxide from flue gas of a sodium silicate kiln, based on the carbon dioxide capture and recovery device of flue gas of a sodium silicate kiln according to claim 9, characterized in that: The following steps are involved: Step 1: First, the first electrically controlled three-way valve (8) is switched to the sodium silicate flue gas supply pipe (10) passage, and the second electrically controlled three-way valve (13) is switched to the flue gas exhaust pipe (14) passage. At this time, the tower body operates as an absorption tower; Step 2: The flue gas is concentratedly introduced into the dust removal pretreatment module through the kiln exhaust pipe to remove particulate matter in the flue gas; Step 3: The flue gas filtered after pretreatment enters the sodium silicate flue gas supply pipe (10) from the exhaust port of the dust removal pretreatment module, and the flow rate and temperature of the flue gas are pre-detected by the temperature flow sensor of the front section of the sodium silicate flue gas supply pipe (10). According to the real-time changes of the inlet temperature and flow rate, the operation quantity of the heat exchange mechanism (11) is adjusted in advance to control the temperature at 40-50°C, and the temperature sensor (12) located in the rear section can further confirm the outlet temperature. If the temperature still exceeds the threshold, the feedback signal is sent to the circulating water chiller to increase the cooling water flow rate to further improve the heat exchange efficiency; Step 4: The flue gas after heat exchange enters the tower base (2) and sequentially passes through a plurality of capture and recovery sections (5) above the tower base (2). An amine solution-modified zeolite filler (501) is provided in each capture and recovery section (55). The amine solution-modified zeolite filler (501) captures and recovers carbon dioxide in the flue gas based on the physical adsorption of the zeolite and the chemical absorption of the amine solution, thereby obtaining a rich liquid after absorbing CO2. Step 5: The flue gas that has absorbed carbon dioxide is discharged from the exhaust pipe (14); Step 6: After one adsorption cycle is completed, the first electrically controlled three-way valve (8) is switched to the rich liquid supply pipe (9) passage, and the second electrically controlled three-way valve (13) is switched to the desorption gas recovery pipe (15) passage. At this time, the tower body operates as a desorption tower; steam heated to 100-120° C. is transported into the tower through the rich liquid supply pipe (9), so that the rich liquid enriched in the amine solution modified zeolite filler (501) releases carbon dioxide under the indirect heating effect of the high-temperature steam, and the desorbed carbon dioxide is recovered through the desorption gas recovery pipe (15); Step 7: The decomposed carbon dioxide enters the condenser through the gas recovery pipe (15) to separate the water and obtain high-purity carbon dioxide; Step 8: In the desorption stage, in order to ensure the efficient adsorption effect of the amine solution modified zeolite filler (501), the amine solution modified zeolite filler (501) is reactivated once every three months. During the reactivation, the valve control mechanism (3) at the connection between the tower base (2) and the capture and recovery section (5) is first driven to control the hydraulic cylinders (305) on both sides of the valve control mechanism (3) to extend, so that the valve plates (303) in the valve plate storage bins (304) on both sides move closer to the center, thereby achieving the closure of the capture and recovery section (5). Afterwards, the amine solution is supplied to the capture and recovery section (5) by the liquid supply pump (17), so that the amine solution submerges the amine solution modified zeolite filler (501). Under the action of physical impregnation, the amine solution is attached to the pores of the zeolite through physical adsorption and capillary action, thereby reactivating the amine solution modified zeolite filler (501).

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