Combined boiler flue gas waste heat recovery carbon sequestration system

Abstract

The invention relates to the technical field of waste heat recovery devices, in particular to a combined boiler flue gas waste heat recovery carbon sequestration system which comprises a first-stage waste heat recovery furnace and a second-stage waste heat recovery furnace which are arranged in series, and the first-stage waste heat recovery furnace and the second-stage waste heat recovery furnace are connected through a breather pipe to form a multi-stage heat exchange structure. A carbon sequestration tower is further arranged on the side, away from the first-stage waste heat recovery furnace, of the second-stage waste heat recovery furnace, two pipe boxes are arranged at the inner end of the first-stage waste heat recovery furnace, the upper ends of the pipe boxes make contact with the bottom end of the top cover, and a plurality of heat exchange pipe bodies allowing flue gas to circulate are arranged between the two pipe boxes. The inner wall of the heat exchange tube body is cleaned in a full-covering mode, the supporting ring rotates in the moving process, the cleaning brush achieves rotary cleaning while moving in the axial direction, clamping stagnation or cleaning dead corners caused by impurity accumulation are effectively avoided, and the cleaning efficiency and the operation stability are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waste heat recovery devices, in particular to a combined boiler flue gas waste heat recovery and carbon sequestration system. BACKGROUND

[0002] With the continuous acceleration of industrialization, energy consumption and greenhouse gas emissions are becoming increasingly serious. As a common heat energy device in industrial production and civil heating, the boiler will emit a large amount of high-temperature flue gas during the combustion process, not only causing energy waste, but also being an important source of carbon dioxide and other greenhouse gases. In order to improve energy utilization efficiency and reduce carbon emissions, waste heat recovery and carbon sequestration technology of boiler flue gas has gradually attracted attention.

[0003] After searching, it is found that the existing technology with publication number CN119436185A discloses a thermal power plant boiler flue gas waste heat recovery device, which comprises a boiler, a carbon cylinder, a recovery barrel, a transfer pipe and a recovery box. The boiler, carbon cylinder, recovery barrel, transfer pipe and recovery box are connected in sequence. The outer side of the boiler is provided with a boiler covering sleeve. The recovery barrel is communicated with the boiler covering sleeve through recovery barrel conveying pipe one or recovery barrel conveying pipe two. It belongs to the technical field of boiler waste heat recovery. The scheme sequentially connects the boiler, carbon cylinder, recovery barrel, transfer pipe and recovery box. The outer side of the boiler is provided with a boiler covering sleeve. The inside of the recovery barrel is provided with a spiral air pipe. One end of the spiral air pipe is communicated with the carbon cylinder. The other end of the spiral air pipe is communicated with the transfer pipe. Therefore, after the flue gas is discharged from the boiler, a part of the particulate waste residue can be filtered out through the carbon cylinder. Then, high-intensity waste heat recovery is carried out in the inside of the recovery barrel through the spiral air pipe. After recovery, the gas is washed in the recovery box through the transfer pipe. After washing, it can be safely discharged.

[0004] Therefore, based on the above search and in combination with the existing technology, in the existing device, the heat exchange pipe structure is mostly fixedly installed. The inside is prone to dust accumulation and scaling. And it generally lacks automatic cleaning or structural adaptive function, which leads to gradual reduction of heat exchange efficiency during long-term operation, affecting the stability of the system. In addition, the existing technology usually adopts a single air pipe structure for waste heat recovery. The heat exchange area is limited. The residence time of flue gas in the heat exchange unit is short. It is difficult to fully utilize the heat energy in different temperature zones, resulting in incomplete heat recovery and low overall energy efficiency. Therefore, the present application proposes a combined boiler flue gas waste heat recovery and carbon sequestration system. SUMMARY

[0005] The purpose of the present application is to provide a combined boiler flue gas waste heat recovery and carbon sequestration system to solve the problems raised in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a combined boiler flue gas waste heat recovery and carbon fixation system, comprising a primary waste heat recovery furnace and a secondary waste heat recovery furnace arranged in series, characterized in that: the primary and secondary waste heat recovery furnaces are connected by a vent pipe to form a multi-stage heat exchange structure; a carbon fixation tower is also provided on the side of the secondary waste heat recovery furnace away from the primary waste heat recovery furnace; a top cover is fitted onto the upper end of the primary waste heat recovery furnace; a water inlet pipe is fixedly connected to the front end of the primary waste heat recovery furnace; two tube boxes are provided at the inner end of the primary waste heat recovery furnace, the two tube boxes are respectively located on the left and right sides inside the primary waste heat recovery furnace, and the upper end face of the tube box is in contact with the lower end face of the top cover; a plurality of heat exchange tubes are arranged between the two tube boxes, and a channel for gas circulation is formed inside the heat exchange tubes; a cleaning device is provided between the heat exchange tubes and the tube boxes, the cleaning device being able to clean impurities on the inner wall of the heat exchange tubes; a distribution box is fixedly installed on the outer surface of the primary waste heat recovery furnace, the distribution box being used to collect and temporarily store flue gas.

[0007] As a further embodiment of the present invention, a passive rack is fixedly connected to the inner end of the tube box, a drive gear is rotatably connected to the upper inner side of the primary waste heat recovery furnace, and the drive gear meshes with the passive rack. A drive motor is fixedly installed at the inner end of the drive gear, and the drive motor is fixedly connected to the inner end of the primary waste heat recovery furnace.

[0008] As a further embodiment of the present invention, the cleaning device includes multiple drums, each corresponding to a heat exchange tube body, and the drums are rotatably mounted on the inner end of the tube box. A cleaning rope is wound and fixed on the outer surface of the drum, and the free end of the cleaning rope extends to the other side of the heat exchange tube body and is fixedly wound on the outer surface of the drum on that side. By setting a drum corresponding to the heat exchange tube body inside the tube box and winding a cleaning rope that passes through the heat exchange tube body on the drum, a bidirectional traction reciprocating cleaning mechanism is formed, thereby achieving efficient and automated cleaning of the inner wall of the heat exchange tube body.

[0009] As a further embodiment of the present invention, a movable block is fixedly sleeved on the outer surface of the cleaning rope, and a support ring is sleeved on the outer surface of the movable block. Multiple cleaning brushes are fixedly installed on the outer surface of the support ring, and the outer surface of the cleaning brushes is in close contact with the inner wall of the heat exchange tube. During the traction of the cleaning rope, the inner wall of the heat exchange tube is effectively scraped and cleaned, effectively removing the accumulated dust or scale on the tube wall, ensuring long-term stable heat exchange efficiency, reducing the frequency of manual maintenance, and extending the service life of the equipment.

[0010] As a further embodiment of the present invention, two drive rods are rotatably installed on the inner bottom of the primary waste heat recovery furnace, and the upper ends of the drive rods pass through the inside of the tube box. A drive gear is rotatably installed on the inner end of the tube box, and the drive rods pass through the inside of the drive gears. The upper and lower adjacent drums are fixedly connected by a passive rod. The bottom ends of the drums near the drive rods are all fixedly installed with passive gears, and the passive gears and the drive gears are tensioned and sleeved by a drive toothed belt.

[0011] As a further embodiment of the present invention, a distribution box is fixedly installed on the outer surface of the primary waste heat recovery furnace, and an air inlet pipe is fixedly connected to the bottom end of the distribution box. Multiple jet pipes are fixedly installed inside the distribution box, and multiple partition plates are fixedly installed at the inner end of the pipe box. The multiple partition plates divide the inner cavity of the pipe box into several independent chambers. The jet pipe is connected to each independent chamber in the pipe box, and an energy storage tube is fixedly sleeved on the inner end of the jet pipe. A spiral rod passes through the inner end of the energy storage tube, and a movable plate is slidably installed on the inner end of the energy storage tube. The movable plate is threaded onto the outer surface of the spiral rod.

[0012] As a further embodiment of the present invention, a buffer tube is fixedly installed at the inner end of the secondary waste heat recovery furnace. The buffer tube is arranged in a spiral shape, and the input end of the buffer tube is connected to the gas pipe. A degassing pipe is fixedly connected to the inner bottom end of the carbon fixation tower, and the output end of the buffer tube and the input end of the degassing pipe are fixedly connected through a conductive pipe.

[0013] As a further embodiment of the present invention, a flow guide shell is fixedly installed at the inner end of the carbon fixation tower, a spray pipe is rotatably installed at the upper inner side of the carbon fixation tower, a plurality of nozzles are fixedly connected to the outer surface of the spray pipe, a waterproof and breathable plate is provided between the flow guide shell and the spray pipe, and the waterproof and breathable plate is fixedly installed at the inner end of the carbon fixation tower in an inclined manner.

[0014] As a further embodiment of the present invention, a spray pump is provided on the side of the carbon fixation tower away from the secondary waste heat recovery furnace. The output end of the spray pump is fixedly connected to a liquid injection pipe. The output end of the liquid injection pipe is connected to the spray pipe through a rotary joint. Multiple branch pipes are fixedly connected to the upper end of the carbon fixation tower. A molecular sieve is provided between two adjacent branch pipes. The molecular sieve further adsorbs harmful substances in the flue gas.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention uses a cleaning motor to drive the active gear to rotate, and a toothed belt drive to make multiple passive gears drive the drum to rotate, thereby driving the cleaning rope to move the support ring inside the heat exchange tube. With the help of a cleaning brush that fits against the tube wall through an interference fit, a full-coverage cleaning of the inner wall of the heat exchange tube is achieved. The support ring rotates during the movement, so that the cleaning brush can rotate and clean while moving axially, effectively avoiding jamming or cleaning dead corners caused by the accumulation of impurities, and improving cleaning efficiency and operational stability. 2. The present invention further provides an expansion bowl and expansion rod structure. When the support ring moves to the limiting ring, the expansion bowl is squeezed and expands radially, which drives the expansion rod and cleaning ring to expand synchronously, thereby realizing the automatic adjustment and tight fit of the cleaning brush. During the expansion process, the cleaning ring performs self-cleaning treatment on the impurities attached to the cleaning brush, ensuring that the air channel is always unobstructed, improving the heat dissipation efficiency of the heat exchange tube and the overall operational reliability. 3. When using this invention, the heat exchange tube body is raised and lowered via the lifting component, which facilitates daily maintenance and cleaning, and improves the convenience and flexibility of system operation. At the same time, the automated design of the inner wall cleaning component and cleaning rope can continuously clean the inner wall of the heat exchange tube body, maintain high heat exchange efficiency, extend the service life of the equipment, and enhance the stability and reliability of system operation. The buffer tube structure set in the secondary waste heat recovery furnace effectively slows down the flue gas flow rate and extends the residence time of the flue gas in the system, so that the harmful components in the flue gas can fully react with the microorganisms or absorbents in the subsequent carbon fixation unit, thereby improving the carbon fixation treatment efficiency. 4. During the use of this invention, the flue gas first accumulates and is stored in the distribution box. When the pressure in the jet pipe reaches a preset threshold, the jet pipe is activated to draw the flue gas in the distribution box. Each jet pipe is equipped with a row of heat exchange tubes to form an independent flue gas flow path, thereby achieving uniform distribution of flue gas among the heat exchange tubes. This effectively avoids local insufficient heat exchange or overheating, ensuring that the water in the primary waste heat recovery furnace obtains a balanced and stable heat exchange effect, and improving the overall heat exchange efficiency and the reliability of system operation. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a combined boiler flue gas waste heat recovery and carbon sequestration system. Figure 2 This is a schematic diagram of the internal structure of a primary waste heat recovery furnace; Figure 3 This is a schematic diagram of the structure at the stirring roller. Figure 4 This is a schematic diagram of the structure at the drive gear. Figure 5 This is a schematic diagram of the structure at the junction of the tube box and the heat exchange tubes. Figure 6This is a schematic diagram of the internal structure of the heat exchanger tube. Figure 7 An exploded view of the movable block and the cleaning brush; Figure 8 This is a schematic diagram of the structure at the junction of the passive gear and the heat exchange tube. Figure 9 This is a schematic diagram of the drive rod and the driving gear structure; Figure 10 This is a schematic diagram of the passive duct and intake duct structure; Figure 11 This is a schematic diagram of the internal structure of the ventilator; Figure 12 A schematic diagram of the internal structure of the secondary waste heat recovery furnace and the carbon fixation tower; Figure 13 This is a schematic diagram of the internal structure of a carbon fixation tower; Figure 14 This is a schematic diagram of the internal structure of the drainage shell; Figure 15 This is a schematic diagram of the internal structure of the jet pipe; Figure 16 This is a diagram showing the installation of the cleaning brush.

[0017] In the diagram: 1. Primary waste heat recovery furnace; 2. Secondary waste heat recovery furnace; 3. Carbon fixation tower; 4. Spray pump; 101. Water inlet pipe; 102. Air inlet pipe; 103. Top cover; 104. Exhaust pipe; 105. Drain pipe; 106. Drive gear; 107. Drive motor; 108. Support rod; 109. Agitator roller; 110. Agitator hub motor; 201. Conductor pipe; 202. Vent pipe; 203. Buffer pipe; 204. Support frame; 205. Mounting ring; 206. Exhaust fan; 301. Branch pipe; 302. Injection pipe; 303. Water outlet; 304. Waterproof and breathable plate; 305. Drainage shell; 306. Degassing pipe; 307. Spray pipe; 308. Molecular sieve; 309. Drive half gear; 310. Spray motor; 311. Air guide plate; 401. Tube box; 402. Heat exchanger tube body; 403. Driven rack; 404. Partition plate; 405. Driven rod; 406. Drum; 407. Driven gear; 408. Drive toothed belt; 409. Drive rod; 411. Drive gear; 412. Slot; 413. Cleaning rope; 414. Moving block; 415. Cleaning brush; 416. Spiral groove; 417. Limiting ring; 418. Cleaning ring; 419. Expansion bowl; 420. Expansion rod; 421. Support ring; 501. Distribution box; 502. Jet pipe; 503. Energy storage pipe; 504. Movable plate; 505. Conductor block; 506. Helical rod; 507. Turbofan; 508. Energy storage torsion spring. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1: Please refer to Figures 1-4 A combined boiler flue gas waste heat recovery and carbon fixation system includes a primary waste heat recovery furnace 1 and a secondary waste heat recovery furnace 2 arranged in series. The primary waste heat recovery furnace 1 and the secondary waste heat recovery furnace 2 are connected by a vent pipe 202 to form a multi-stage heat exchange structure. A carbon fixation tower 3 is also provided on the side of the secondary waste heat recovery furnace 2 away from the primary waste heat recovery furnace 1. A top cover 103 is fitted on the upper end of the primary waste heat recovery furnace 1, and an exhaust pipe 104 is fixedly connected to the upper end of the top cover 103. The front end of the primary waste heat recovery furnace 1 is fixedly connected to... The primary waste heat recovery furnace 1 is equipped with a water inlet pipe 101 and two tube boxes 401 are located at the inner end of the furnace. The two tube boxes 401 are located on the left and right sides of the furnace. The upper end face of the tube box 401 is in contact with the lower end face of the top cover 103. Several heat exchange tubes 402 are arranged between the two tube boxes 401. A channel for gas circulation is formed inside the heat exchange tubes 402. A cleaning device is provided between the heat exchange tubes 402 and the tube box 401. The cleaning device can clean the impurities on the inner wall of the heat exchange tubes 402. Specifically, the heat exchange tubes 402 are arranged in a rectangular array. The primary waste heat recovery furnace 1 has multiple stirring rollers 109 inside, which are located between the heat exchange tubes 402. Multiple support rods 108 are fixedly installed at the inner end of the primary waste heat recovery furnace 1, and the support rods 108 are rotatably connected to the stirring rollers 109 through rotating shafts. The inner end of each stirring roller 109 is fixedly installed with a stirring hub motor 110 by bolts. The stirring hub motor 110 and the stirring roller 109 are connected by a sealing gasket to prevent water from entering the internal components of the stirring hub motor 110. The stirring hub motor 110 is fixedly connected to the support rods 108 by bolts. The interior of the primary waste heat recovery furnace 1 is filled with water, which completely submerges the heat exchange tubes 402. The stirring rollers 109 rotate to keep the water inside the primary waste heat recovery furnace 1 in a flowing state, thereby preventing the high temperature of the heat exchange tubes 402 from causing a continuous increase in local water temperature. The outer surface of the primary waste heat recovery furnace 1 is fixedly connected with a water inlet pipe 101 and a drain pipe 105. The water inlet pipe 101 is located above the primary waste heat recovery furnace 1, and the drain pipe 105 is located below the primary waste heat recovery furnace 1.

[0020] like Figure 2 , Figure 4 , Figure 5 As shown, a passive rack 403 is fixed to the inner end of the tube box 401. The upper inner side of the primary waste heat recovery furnace 1 is rotatably connected to a drive gear 106 via a rotating shaft. The drive gear 106 meshes with the passive rack 403. When the drive gear 106 rotates, it drives the passive rack 403 to move upward in the vertical direction, thereby causing the tube box 401 to rise synchronously and be fully exposed to the outside, so as to facilitate subsequent cleaning and maintenance operations. The inner end of the drive gear 106 is fixedly mounted with a drive motor 107 by bolts, and the drive motor 107 is fixedly connected to the inner end of the primary waste heat recovery furnace 1.

[0021] Example 2: Please refer to Figures 5-8 , Figure 16 A combined boiler flue gas waste heat recovery and carbon fixation system, based on Embodiment 1, includes a cleaning device comprising multiple drums 406, which correspond to heat exchange tubes 402 and are rotatably mounted on the inner end of a tube box 401. A cleaning rope 413 is wound and fixed on the outer surface of the drum 406. The free end of the cleaning rope 413 extends to the other side of the heat exchange tube 402 and is fixedly wound on the outer surface of the drum 406 on that side. A movable block 414 is fixedly sleeved on the outer surface of the cleaning rope 413, and a support ring 421 is sleeved on the outer surface of the movable block 414. Multiple cleaning brushes 415 are fixedly installed on the outer surface of the support ring 421, and the outer surface of the cleaning brushes 415 is in close contact with the inner wall of the heat exchange tube 402. The heat exchange tube body 402 has symmetrically welded limit rings 417 at both ends. The support ring 421 has two expansion bowls 419. When the expansion bowls 419 move axially until they contact the outer surface of the limit rings 417, they undergo radial expansion deformation under axial extrusion force. The outer surface of the support ring 421 has a number of expansion rods 420 evenly distributed around it. The end of each expansion rod 420 is fixedly connected to the corresponding expansion bowl 419. The outer surface of the support ring 421 is equipped with a cleaning ring 418, which is fixedly connected to the expansion rods 420. The cleaning brush 415 is slidably disposed inside the cleaning ring 418. When the expansion rod 420 is driven by the expansion bowl 419 to produce radial displacement, it synchronously drives the cleaning ring 418 to perform radial expansion movement. During this expansion process, the inner wall of the cleaning ring 418 and the outer surface of the cleaning brush 415 produce relative movement, automatically removing impurities attached to the outer surface of the cleaning brush 415, thereby maintaining the unobstructed airflow channel. When the support ring 421 moves inside the heat exchange tube 402, the cleaning brush 415 fits snugly against the inner wall of the heat exchange tube 402 due to the interference fit, thereby achieving a thorough cleaning of the inner wall of the heat exchange tube 402. Specifically, the inner wall of the heat exchange tube 402 is provided with a spiral groove 416, and a snap-fit ​​block is fixedly welded to the outer surface of the support ring 421. The snap-fit ​​block is embedded in the spiral groove 416. When the support ring 421 reciprocates inside the heat exchange tube 402, the cooperation between the snap-fit ​​block and the spiral groove 416 forces the support ring 421 to rotate. This rotation causes the cleaning brush 415 to rotate axially while moving axially, thereby avoiding movement obstruction caused by the accumulation of impurities on the inner wall of the heat exchange tube 402.

[0022] like Figure 5 , Figure 8 , Figure 9 As shown, two cleaning motors (not shown in the figure) are fixedly installed at the bottom of the primary waste heat recovery furnace 1 by bolts. The two cleaning motors correspond to two tube boxes 401 respectively. Two drive rods 409 are rotatably installed on the inner bottom of the primary waste heat recovery furnace 1. The bottom end of the drive rod 409 is fixedly connected to the output end of the cleaning motor, and the upper end of the drive rod 409 passes through the inside of the tube box 401. The inner end of the tube box 401 is rotatably installed with a drive gear 411 through an extension block. The drive rod 409 passes through the inside of the drive gear 411. Specifically, a slot 412 is opened at the end of the drive rod 409 near the drive gear 411. A locking block is fixedly installed at the inner end of the drive gear 411. The locking block passes through the inside of the slot 412. More specifically, the outer peripheral surface of the locking block has an elliptical outline. When the drive gear 411 moves downward, the locking block forms an adaptive fit with the slot 412 set on the outer surface of the drive rod 409 through its elliptical outer peripheral surface. Two adjacent upper and lower drums 406 are fixedly connected by a passive rod 405. A passive gear 407 is fixedly installed at the bottom end of each drum 406 near the drive rod 409. The passive gear 407 and the drive gear 411 are on the same horizontal plane, and the passive gear 407 and the drive gear 411 are tensioned and sleeved by a drive toothed belt 408. Specifically, a tensioner is fixedly installed at the inner end of the tube box 401. The outer surface of the tensioner contacts the outer surface of the drive toothed belt 408 to ensure that the drive toothed belt 408 can better mesh with the passive gear 407 and the drive gear 411.

[0023] like Figure 1 , Figure 5 , Figure 10 , Figure 11 , Figure 15As shown, a distribution box 501 is fixedly installed on the outer surface of the primary waste heat recovery furnace 1. The distribution box 501 is used to collect and temporarily store flue gas. An air inlet pipe 102 is fixedly connected to the bottom end of the distribution box 501 by a clamp. Multiple jet pipes 502 are fixedly installed inside the distribution box 501. Multiple partition plates 404 are fixedly installed at the inner end of the tube box 401. The multiple partition plates 404 divide the inner cavity of the tube box 401 into several independent chambers. In each independent chamber, several heat exchange tubes 402 arranged side by side form a continuous gas flow channel. The jet pipe 502 is connected to each independent chamber in the pipe box 401, and the inner end of the jet pipe 502 is fixedly fitted with an energy storage pipe 503. The inner end of the energy storage pipe 503 is fitted with a spiral rod 506. The inner end of the energy storage pipe 503 is slidably installed with a movable plate 504, and the movable plate 504 is threaded onto the spiral rod 506. Specifically, the movable plate 504 has a rectangular groove, and the inner end of the energy storage pipe 503 is fixedly installed with a rectangular strip. The rectangular groove is fitted onto the rectangular strip, so that the movable plate 504 cannot rotate during the movement, while the spiral rod 506 begins to rotate during the movement of the movable plate 504. A turbofan 507 is rotatably mounted on the end of the energy storage tube 503 away from the movable plate 504, and the turbofan 507 is fixedly connected to the screw rod 506. The turbofan 507 is also engaged with the jet pipe 502 via an energy storage torsion spring 508. Specifically, abutment rings are fixedly installed on both the left and right ends of the inner side of the energy storage tube 503. Multiple guide blocks 505 are passed through the outer surface of the movable plate 504, and ventilation grooves are formed on the outer surface of the guide blocks 505. Initially, the ventilation grooves do not connect the chambers on both sides of the movable plate 504. However, when the movable plate 504 moves to the inner right end of the energy storage tube 503 (e.g., ...), the ventilation grooves will connect the chambers on both sides of the movable plate 504. Figure 15 As shown), with the continuous movement of the movable plate 504, the conductive block 505 moves away from the turbofan 507, so that the ventilation groove connects the chambers on both sides of the movable plate 504.

[0024] like Figure 11 As shown, the primary waste heat recovery furnace 1 and the secondary waste heat recovery furnace 2 are connected by a vent pipe 202, and a support frame 204 is fixedly installed at the inner end of the vent pipe 202. An installation ring 205 is detachably connected inside the support frame 204. Specifically, a polycarbonate membrane is fixedly installed at the inner end of the installation ring 205. The polycarbonate membrane is used to filter the airflow and can effectively block particulate pollutants in the air. At the same time, the installation ring 205 can be removed from the support frame 204 to facilitate better replacement of the polycarbonate membrane during maintenance. Specifically, an exhaust fan 206 is installed at the inner end of the vent pipe 202. When the exhaust fan 206 is running, it creates a negative pressure inside the heat exchange tube 402, thereby accelerating the suction and flow of flue gas and improving the flue gas treatment efficiency. A pressure regulating valve (not shown in the figure) is installed at the connection between the vent pipe 202 and the primary waste heat recovery furnace 1. The pressure regulating valve is used to regulate the gas pressure inside the vent pipe 202 so that the exhaust fan 206 maintains a stable flue gas delivery state during operation.

[0025] like Figures 12-14 As shown, a buffer pipe 203 is fixedly installed at the inner end of the secondary waste heat recovery furnace 2 by clamps. The buffer pipe 203 is arranged in a spiral shape, and the input end of the buffer pipe 203 is connected to the vent pipe 202. The inner bottom end of the carbon fixation tower 3 is fixedly connected to the degassing pipe 306 by bolts. Multiple exhaust microholes are opened on the outer surface of the degassing pipe 306, and the output end of the buffer pipe 203 and the input end of the degassing pipe 306 are fixedly connected by a conductor pipe 201. It should be noted that a water supply pipe and a water outlet pipe (not shown in the figure) are connected to one side of the bottom of the carbon fixation tower 3 so that the spray liquid can be heated to the bottom of the carbon fixation tower 3 and then the solution after the reaction can be recovered, thereby realizing the absorption of carbon dioxide. Specifically, the inner end of the secondary waste heat recovery furnace 2 is also filled with water, and the spiral buffer tube 203 can better increase the heating area and effectively slow down the flow rate of flue gas.

[0026] The inner end of the carbon fixation tower 3 is fixedly installed with a flow guide shell 305 by bolts. The interior of the flow guide shell 305 is filled with microorganisms or chemical absorbents to absorb harmful substances in the flue gas, thereby improving the carbon fixation efficiency. A spray pipe 307 is rotatably installed on the upper inner side of the carbon fixation tower 3. Multiple nozzles are fixedly connected to the outer surface of the spray pipe 307, with the nozzles facing the flow guide shell 305. A waterproof and breathable plate 304 is provided between the flow guide shell 305 and the spray pipe 307. The waterproof and breathable plate 304 is an existing mature technology and will not be described in detail here. The waterproof and breathable plate 304 is fixedly installed at the inner end of the carbon fixation tower 3 in an inclined shape. The outer surface of the carbon fixation tower 3 is provided with a water outlet 303. The position of the water outlet 303 corresponds to the inclined bottom end of the waterproof and breathable plate 304, so that the liquid accumulated on the waterproof and breathable plate 304 can flow along the inclined surface to the water outlet 303 and be discharged.

[0027] A spray pump 4 is installed on the side of the carbon fixation tower 3 away from the secondary waste heat recovery furnace 2. The output end of the spray pump 4 is fixedly connected to the injection pipe 302. The output end of the injection pipe 302 is connected to the spray pipe 307 through a rotary joint. The rotary joint allows the spray pipe 307 to rotate relative to the injection pipe 302 while maintaining the liquid seal to ensure that no leakage occurs during rotation. A spray motor 310 is fixedly installed on the outer surface of the carbon fixation tower 3 by bolts. A drive half gear 309 is fixedly installed at the output end of the spray motor 310. A passive half gear is fixedly installed on the outer surface of the spray pipe 307, and the drive half gear 309 meshes with the passive half gear. The upper end of the carbon fixation tower 3 is fixedly connected with multiple branch pipes 301 by bolts. A molecular sieve 308 is set between two adjacent branch pipes 301. The molecular sieve 308 further adsorbs harmful substances in the flue gas to reduce the pollutant content in the emitted flue gas. The inner end of the flow guide shell 305 is provided with multiple rectangular holes. A guide plate 311 can be detachably installed in each rectangular hole, so that the flue gas can pass through the guide plate 311 and enter the flow guide shell 305, and come into contact with the microorganisms or chemical absorbent inside the flow guide shell 305.

[0028] The working principle of this invention is: During operation, the primary waste heat recovery furnace 1 and the secondary waste heat recovery furnace 2 are first filled with water. Then, the flue gas enters the distribution box 501 through the inlet pipe 102. As the pressure inside the distribution box 501 increases, it pushes the movable plate 504 to move. During this movement, the movable plate 504 drives the screw rod 506 to rotate. The rotation of the screw rod 506 compresses the energy storage torsion spring 508. The movable plate 504 moves into the energy storage pipe 503 and contacts the abutment ring near the turbine fan 507. As 504 continues to move, the conducting block 505 moves away from the turbo fan 507, causing the ventilation slot to connect the chambers on both sides of the movable plate 504. At this time, the pressure inside the energy storage tube 503 is released, and the energy storage torsion spring 508 releases its elastic force, driving the turbo fan 507 to rotate. At this time, the flue gas is drawn into the distribution box 501 as the turbo fan 507 rotates. Then, the flue gas passes through the movable plate 504 and enters the divided chamber in the tube box 401, and flows into the interior of multiple heat exchange tubes 402 in the current chamber. Flue gas is collected and stored in the distribution box 501. When the pressure in the jet pipe 502 reaches the preset threshold, the jet pipe 502 will draw the flue gas in the distribution box 501. Each jet pipe 502 is equipped with a row of heat exchange tubes 402 to form an independent flue gas flow path, ensuring that the flue gas is evenly distributed to each heat exchange tube 402, so that the water in the first-stage waste heat recovery furnace 1 can obtain a uniform heat exchange effect. When the screw rod 506 rotates with the turbo fan 507, it drives the movable plate 504 to move axially, causing the conductive block 505 on the outer surface of the movable plate 504 to contact the abutment ring at the end of the energy storage tube 503. Under the reverse force of the abutment ring, the conductive block 505 is displaced and reset to the initial working position. The high-temperature flue gas heats the heat exchange tube 402, and then is immediately cooled by the water submerged outside. The flue gas then flows from the vent pipe 202 into the interior of the buffer pipe 203, effectively slowing down the flow rate of the flue gas. Subsequently, the flue gas flows out from the exhaust micropores on the outer surface of the degassing pipe 306, mixes directly with the spray liquid injected by the water supply pipe, and rises into the microbial reaction zone and spray zone, so that the harmful substances in the flue gas can come into more complete contact with the microorganisms or chemical absorbents in the carbon fixation tower 3, and the reaction solution is recovered through the water outlet pipe. The output end of the spray motor 310 drives the active half gear 309 to rotate back and forth, and the spray pipe 307 also swings accordingly. The flue gas comes into full contact with the spray liquid as it passes through the waterproof and breathable plate 304, completing secondary purification, and finally flows out from the branch pipe 301. When the heat exchange tube 402 is used for a long time, impurities will accumulate on its inner wall. At this time, the output end of the cleaning motor drives the drive gear 411 to rotate through the drive rod 409, while the output end of the cleaning motor on the other side rotates in the opposite direction. When the drive gear 411 rotates, it drives multiple driven gears 407 to rotate through the drive belt 408. Then, the driven gears 407 drive the drum 406 to rotate, and the support ring 421 moves inside the heat exchange tube 402 through the cleaning rope 413. The cleaning brush 415 fits fully against the inner wall of the heat exchange tube 402 due to the interference fit, thereby achieving a comprehensive cleaning of the inner wall of the heat exchange tube 402. The support ring 421 rotates during the movement. This rotation causes the cleaning brush 415 to rotate axially while moving axially, thereby avoiding movement obstruction caused by the accumulation of impurities on the inner wall of the heat exchange tube 402.

[0029] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A combined boiler flue gas waste heat recovery and carbon sequestration system, comprising a primary waste heat recovery furnace (1) and a secondary waste heat recovery furnace (2) arranged in series, characterized in that: The primary waste heat recovery furnace (1) and the secondary waste heat recovery furnace (2) are connected by a vent pipe (202) to form a multi-stage heat exchange structure. A carbon fixation tower (3) is also provided on the side of the secondary waste heat recovery furnace (2) away from the primary waste heat recovery furnace (1). A top cover (103) is fitted on the upper end of the primary waste heat recovery furnace (1). A water inlet pipe (101) is fixedly connected to the front end of the primary waste heat recovery furnace (1). Two pipe boxes (401) are provided at the inner end of the primary waste heat recovery furnace (1). The two pipe boxes (401) are located inside the primary waste heat recovery furnace (1). On the left and right sides of the part, the upper end face of the tube box (401) is in contact with the lower end face of the top cover (103). A number of heat exchange tubes (402) are arranged between the two tube boxes (401). The heat exchange tubes (402) form a channel for gas flow. A cleaning device is provided between the heat exchange tubes (402) and the tube box (401). The cleaning device can clean the impurities on the inner wall of the heat exchange tubes (402). A distribution box (501) is fixedly installed on the outer surface of the primary waste heat recovery furnace (1). The distribution box (501) is used to collect and temporarily store flue gas.

2. The combined boiler flue gas waste heat recovery and carbon sequestration system according to claim 1, characterized in that: A passive rack (403) is fixedly connected to the inner end of the tube box (401). A drive gear (106) is rotatably connected to the upper inner side of the primary waste heat recovery furnace (1). The drive gear (106) meshes with the passive rack (403). A drive motor (107) is fixedly installed on the inner end of the drive gear (106). The drive motor (107) is fixedly connected to the inner end of the primary waste heat recovery furnace (1).

3. A combined boiler flue gas waste heat recovery and carbon sequestration system according to claim 2, characterized in that: The cleaning device includes multiple drums (406), which correspond to the heat exchange tube body (402) and are rotatably mounted on the inner end of the tube box (401). A cleaning rope (413) is wound and fixed on the outer surface of the drum (406), and the free end of the cleaning rope (413) extends to the other side of the heat exchange tube body (402) and is fixedly wound on the outer surface of the drum (406) on that side.

4. A combined boiler flue gas waste heat recovery and carbon sequestration system according to claim 3, characterized in that: The outer surface of the cleaning rope (413) is fixedly fitted with a movable block (414), and the outer surface of the movable block (414) is fitted with a support ring (421). The outer surface of the support ring (421) is fixedly installed with a plurality of cleaning brushes (415), and the outer surface of the cleaning brushes (415) is in close contact with the inner wall of the heat exchange tube body (402).

5. A combined boiler flue gas waste heat recovery and carbon sequestration system according to claim 4, characterized in that: Two drive rods (409) are rotatably installed on the inner bottom of the primary waste heat recovery furnace (1), and the upper end of the drive rods (409) passes through the inside of the tube box (401). The inner end of the tube box (401) is rotatably installed with a drive gear (411), and the drive rods (409) pass through the inside of the drive gear (411). The upper and lower adjacent drums (406) are fixedly connected by a passive rod (405). The bottom end of the drum (406) near the drive rod (409) is fixedly installed with a passive gear (407), and the passive gear (407) and the drive gear (411) are tensioned and sleeved by a drive toothed belt (408).

6. A combined boiler flue gas waste heat recovery and carbon sequestration system according to claim 1, characterized in that: An air inlet pipe (102) is fixedly connected to the bottom end of the distribution box (501). Multiple jet pipes (502) are fixedly installed inside the distribution box (501). Multiple partition plates (404) are fixedly installed at the inner end of the pipe box (401). The multiple partition plates (404) divide the inner cavity of the pipe box (401) into several independent chambers. The jet pipe (502) is connected to each independent chamber in the pipe box (401), and the inner end of the jet pipe (502) is fixedly fitted with an energy storage pipe (503). The inner end of the energy storage pipe (503) is fitted with a spiral rod (506), and the inner end of the energy storage pipe (503) is slidably installed with a movable plate (504), and the movable plate (504) is threaded onto the outer surface of the spiral rod (506).

7. A combined boiler flue gas waste heat recovery and carbon sequestration system according to claim 1, characterized in that: A buffer tube (203) is fixedly installed at the inner end of the secondary waste heat recovery furnace (2). The buffer tube (203) is arranged in a spiral shape, and the input end of the buffer tube (203) is connected to the gas pipe (202). A degassing pipe (306) is fixedly connected to the bottom inner side of the carbon fixation tower (3), and the output end of the buffer tube (203) and the input end of the degassing pipe (306) are fixedly connected through a conductor pipe (201).

8. A combined boiler flue gas waste heat recovery and carbon sequestration system according to claim 7, characterized in that: The inner end of the carbon fixation tower (3) is fixedly installed with a flow guide shell (305), and a spray pipe (307) is rotatably installed on the upper inner side of the carbon fixation tower (3). Multiple nozzles are fixedly connected to the outer surface of the spray pipe (307). A waterproof and breathable plate (304) is provided between the flow guide shell (305) and the spray pipe (307), and the waterproof and breathable plate (304) is fixedly installed at the inner end of the carbon fixation tower (3) in an inclined manner.

9. A combined boiler flue gas waste heat recovery and carbon sequestration system according to claim 8, characterized in that: The carbon fixation tower (3) is equipped with a spray pump (4) on the side away from the secondary waste heat recovery furnace (2). The output end of the spray pump (4) is fixedly connected to a liquid injection pipe (302). The output end of the liquid injection pipe (302) is connected to the spray pipe (307) through a rotary joint. The upper end of the carbon fixation tower (3) is fixedly connected to multiple branch pipes (301). A molecular sieve (308) is set between two adjacent branch pipes (301). The molecular sieve (308) further adsorbs harmful substances in the flue gas.

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