Biomass oxygen-enriched combustion boiler flue gas and air system

Abstract

The invention relates to the technical field of biomass power generation, and discloses a biomass oxygen-enriched combustion boiler flue gas and air system which comprises a biomass boiler, the output end of the biomass boiler communicates with a coal economizer, the output end of the coal economizer communicates with a smoke pipe, and a cyclone dust collector is installed on the outer wall of the smoke pipe; the interior of the cyclone dust collector communicates with a bag-type dust collector through a pipeline, the interior of the bag-type dust collector communicates with a denitrator through a pipeline, a feeding pipe is installed in the denitrator, the output end of the denitrator communicates with a smoke cooler, and an induced draft fan is installed at the output end of the smoke cooler; and the output end of the induced draft fan is communicated with a three-way pipe. Smoke entering the fixed cylinder is combed through rotation of the impeller under the suction force of the booster fan, meanwhile, the knocking frame and the cleaning plate are driven to clean and knock the filter screen, impurities attached to the filter screen are reduced, gas penetrates through the filter screen and is treated in the adsorption tower, and carbon capture branch conveying and self-cleaning are achieved.

Description

Technical Field

[0001] This invention relates to the field of biomass power generation technology, specifically to a biomass oxygen-enriched combustion boiler flue gas system. Background Technology

[0002] Because biomass oxygen-enriched combustion technology can effectively reduce nitrogen oxide emissions and improve biomass fuel utilization, it has become one of the core development directions in the field of biomass boilers. As a key supporting link for this technology to achieve carbon emission reduction targets, the stability and efficiency of its branch operation directly determine the environmental performance and operational economy of the entire flue gas system.

[0003] Existing biomass oxy-fuel combustion boiler flue gas systems directionally transport pretreated high-concentration carbon-containing flue gas to an adsorption tower, where carbon dioxide is separated and captured through pressure swing adsorption (PSA). The fixed cylinder, acting as a transition pipe between the T-junction and the booster fan, plays a crucial role in guiding flue gas flow and intercepting impurities. It typically contains a filter screen. However, fine impurities in the flue gas generated by biomass oxy-fuel combustion easily adhere to the filter screen surface, leading to filter blockage over long-term operation. This results in unstable flue gas delivery, fluctuations in the adsorption tower inlet conditions, and ultimately, reduced carbon dioxide capture efficiency. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a flue gas system for a biomass oxygen-enriched combustion boiler, which solves the problem that long-term operation can easily lead to filter clogging, resulting in unstable flue gas delivery and affecting carbon dioxide capture efficiency.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a biomass oxygen-enriched combustion boiler flue gas system, comprising a biomass boiler, an economizer connected to the output end of the biomass boiler, a flue pipe connected to the output end of the economizer, a cyclone dust collector installed on the outer wall of the flue pipe, a bag filter connected to the inside of the cyclone dust collector via a pipe, a denitrification unit connected to the inside of the bag filter via a pipe, a feed pipe installed inside the denitrification unit, a flue gas cooler connected to the output end of the denitrification unit, an induced draft fan installed at the output end of the flue gas cooler, a tee pipe connected to the output end of the induced draft fan, a chimney connected to the right side of the tee pipe via a pipe, a fixed cylinder connected to the rear side of the tee pipe, a booster fan installed on the outer wall of the fixed cylinder, an adsorption tower connected to the output end of the booster fan, and a flow diversion mechanism provided inside the fixed cylinder.

[0006] The above scheme involves burning biomass in a biomass boiler to produce high-temperature flue gas, which serves as the source of flue gas for the entire flue gas system. The economizer is connected to the boiler output end to recover the waste heat of the high-temperature flue gas to heat the boiler feedwater, thereby improving energy utilization efficiency. At the same time, it reduces the flue gas temperature and alleviates the heat load on subsequent equipment. The flue pipe serves as the main pipeline for flue gas transportation, responsible for transporting the flue gas discharged from the economizer to the subsequent pretreatment equipment. The airflow is guided by an induced draft fan through a three-way pipe for diversion. A portion of the gas passes through a fixed cylinder, a booster fan, and an adsorption tower for carbon capture, while the remaining gas enters the interior of the chimney for discharge.

[0007] Preferably, the drainage mechanism includes a cross, the outer wall of which is fixedly connected to the inside of the fixed cylinder, a connecting rod is rotatably connected to the inside of the cross, and an impeller is fixedly connected to the outer wall of the connecting rod.

[0008] Preferably, a filter screen is rotatably connected to the outer wall of the connecting rod, the outer wall of the filter screen is installed inside the fixed cylinder, and a striking frame and a cleaning plate are fixedly connected to the outer wall of the connecting rod, with the outer walls of the striking frame and the cleaning plate both located on the outer wall of the filter screen.

[0009] Preferably, a flow rectifier is installed inside the tee pipe, a flow deflector is slidably connected inside the tee pipe, a sleeve is slidably connected to the outer wall of the flow deflector, and the outer wall of the sleeve is fixedly connected to the inside of the tee pipe.

[0010] Preferably, one end of the spring is fixedly connected to the outer wall of the baffle, and the other end of the spring is fixedly connected to the inside of the tee pipe.

[0011] Preferably, one end of the flue is fixedly connected to a tension spring, and the other end of the tension spring is fixedly connected to a U-shaped frame.

[0012] Preferably, a transmission rod is fixedly connected to the inner side of the U-shaped frame, and an irregularly shaped block is provided on the outer wall of the transmission rod.

[0013] Preferably, a striking ball is fixedly connected to the outer wall of the irregularly shaped block, and the outer wall of the striking ball is disposed on the inner wall of the flue.

[0014] Preferably, the irregularly shaped block is internally connected to a limiting rod, and the outer wall of the limiting rod is fixedly connected to the outer wall of the flue.

[0015] Preferably, the outer wall of the limiting rod is slidably connected to the inside of the U-shaped frame.

[0016] Working principle: High-temperature flue gas is generated by burning biomass fuel in a biomass boiler. It first enters the economizer, where the waste heat of the flue gas is recovered to heat the boiler feedwater. Then, the flue gas is transported through the flue pipe to the cyclone dust collector, where large particles of fly ash and carbon particles are separated by centrifugal force. It then enters the bag filter dust collector, where fine particles are removed by the filter bags, ensuring that the dust content of the flue gas meets the standards. Subsequently, it enters the denitrification unit, where a denitrification agent is quantitatively added into the denitrification unit through the feed pipe. At the appropriate temperature, nitrogen oxides in the flue gas are removed, completing the denitrification and purification. The high-temperature flue gas after denitrification enters the flue gas cooler to be cooled to the appropriate temperature for carbon capture. Then, the induced draft fan guides the airflow through the three-way pipe for diversion. A portion of the gas passes through the fixed cylinder, the booster fan, and the adsorption tower for carbon capture, while the remaining gas enters the interior of the chimney for discharge.

[0017] This invention provides a flue gas system for a biomass oxygen-enriched combustion boiler. It has the following beneficial effects: 1. This invention uses an impeller that rotates under the suction of a booster fan to comb through the flue gas entering the fixed cylinder. At the same time, it drives the knocking frame and cleaning plate to clean and knock the filter screen, reducing the amount of debris adhering to the filter screen. The gas passes through the filter screen and is processed in the adsorption tower, realizing carbon capture branch transportation and self-cleaning, reducing the frequency of manual filter screen cleaning and enhancing the stability of system operation.

[0018] 2. In this invention, when the airflow thrust inside the three-way pipe is greater than the spring force, the baffle retracts; when the airflow thrust is less than the spring force, the baffle extends, actively diverting the airflow. Furthermore, it automatically adjusts according to the suction force of the booster fan and the amount of flue gas, assisting the booster fan in extracting the airflow inside the three-way pipe.

[0019] 3. This invention uses the cooperation of a U-shaped frame, transmission rod, irregular block, striking ball, limiting rod and tension spring to remove debris adhering to the inner wall of the flue pipe during use, optimize the resistance of flue gas flow inside the flue pipe, and the removed debris enters the interior of the cyclone dust collector for effective treatment, preventing blockage of the pipeline connecting the economizer and the cyclone dust collector. Attached Figure Description

[0020] Figure 1 This is a three-dimensional schematic diagram of the present invention; Figure 2 This is a partial structural diagram of the fixed cylinder of the present invention; Figure 3 This is a partial structural diagram of the tee pipe of the present invention; Figure 4 This is a schematic diagram of a partial impeller structure of the present invention; Figure 5 This is a schematic diagram of a partial structure of the sleeve of the present invention; Figure 6 This is a partial structural diagram of the U-shaped frame of the present invention; Figure 7This is a schematic diagram of a partial structure of the irregular block of the present invention.

[0021] Among them, 1. Biomass boiler; 2. Economizer; 3. Flue; 4. Cyclone dust collector; 5. Bag dust collector; 6. Denitrifier; 7. Feed pipe; 8. Flue gas cooler; 9. Exhaust fan; 10. T-pipe; 11. Chimney; 12. Fixed cylinder; 13. Booster fan; 14. Adsorption tower; 15. Diversion mechanism; 151. Cross; 152. Connecting rod; 153. Impeller; 154. Filter screen; 155. Impact frame; 156. Cleaning plate; 16. Baffle frame; 17. Sleeve; 18. Spring; 19. Rectifier plate; 20. U-shaped frame; 21. Transmission rod; 22. Irregular block; 23. Impact ball; 24. Limiting rod; 25. Tension spring. Detailed Implementation

[0022] The technical solution of the present invention will now be clearly and completely described 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.

[0023] Please see the appendix Figure 1 -Appendix Figure 3 This invention provides a biomass oxygen-enriched combustion boiler flue gas system, including a biomass boiler 1, an economizer 2 connected to the output end of the biomass boiler 1, a flue pipe 3 connected to the output end of the economizer 2, a cyclone dust collector 4 installed on the outer wall of the flue pipe 3, a bag filter 5 connected to the inside of the cyclone dust collector 4 via a pipe, a denitrification device 6 connected to the inside of the bag filter 5 via a pipe, a feed pipe 7 installed inside the denitrification device 6, a flue gas cooler 8 connected to the output end of the flue gas cooler 8, an induced draft fan 9 installed at the output end of the induced draft fan 9, a three-way pipe 10 connected to the output end of the three-way pipe 10 via a pipe, a chimney 11 connected to the right side of the three-way pipe 10, a fixed cylinder 12 connected to the rear side of the three-way pipe 10, a booster fan 13 installed on the outer wall of the fixed cylinder 12, an adsorption tower 14 connected to the output end of the booster fan 13, and a diversion mechanism 15 provided inside the fixed cylinder 12.

[0024] Specifically, the flue gas output from the fixed cylinder 12 is divided into two parts by using the three-way pipe 10 as the flue gas diversion node. One part is discharged through the chimney 11, while the other part is sent into the carbon capture pipeline, namely the fixed cylinder 12 and its connecting components. It is installed inside the denitrifier 6 through the feed pipe 7. The external control component is used to quantitatively add the denitrification agent to react with the flue gas inside the denitrifier 6. The pipeline before the bag filter 5 can all use the flue pipe 3 and its internal components to reduce the adhesion of impurities in the flue gas to the inner wall of the pipeline and ensure the connection between the economizer 2, the cyclone dust collector 4 and the bag filter 5. The fixed cylinder 12 connects the three-way pipe 10 to the transition pipeline of the carbon capture booster fan 13, and its internal integrated diversion mechanism 15 optimizes the flue gas flow field and improves the carbon capture flue gas conveying efficiency. Then, the adsorption tower 14 uses the pressure swing adsorption process to separate carbon dioxide in the flue gas, realizing the capture and purification of carbon dioxide.

[0025] Please see the appendix Figure 3 -Appendix Figure 4 The drainage mechanism 15 includes a cross 151, the outer wall of which is fixedly connected to the inside of the fixed cylinder 12, a connecting rod 152 is rotatably connected inside the cross 151, and an impeller 153 is fixedly connected to the outer wall of the connecting rod 152.

[0026] Specifically, the cross 151 provides support for the rotation of the connecting rod 152 and the impeller 153, while the connecting rod 152 drives the cleaning component through the impeller 153. The impeller 153 rotates with the flow of flue gas, thus combing the flue gas entering the fixed cylinder 12.

[0027] Please see the appendix Figure 4 A filter screen 154 is rotatably connected to the outer wall of the connecting rod 152. The outer wall of the filter screen 154 is installed inside the fixed cylinder 12. A striking frame 155 and a cleaning plate 156 are fixedly connected to the outer wall of the connecting rod 152. The outer walls of the striking frame 155 and the cleaning plate 156 are both set on the outer wall of the filter screen 154.

[0028] Specifically, the filter screen 154 intercepts residual fine particles in the flue gas by capturing carbon, protecting the subsequent adsorption equipment. The cleaning plate 156 scrapes the surface of the filter screen 154 to help clean the attached fine impurities. The striking frame 155 is composed of an elastic element and a ball bearing. The elastic element presses against the ball bearing as it moves on the surface of the filter screen 154. The ball bearing is pressed against the groove opened inside the filter screen 154 to strike the filter screen 154.

[0029] Please see the appendix Figure 3 -Appendix Figure 5 A rectifier plate 19 is installed inside the three-way pipe 10. A flow deflector 16 is slidably connected inside the three-way pipe 10. A sleeve 17 is slidably connected to the outer wall of the flow deflector 16. The outer wall of the sleeve 17 is fixedly connected to the inside of the three-way pipe 10.

[0030] Specifically, the flow after diversion is optimized by the rectifier plate 19 to reduce flue gas turbulence. A short rod is provided on the side of the baffle 16 near the sleeve 17 and slides inside the sleeve 17 to limit the movement of the baffle 16.

[0031] Please see the appendix Figure 5 One end of a spring 18 is fixedly connected to the outer wall of the baffle 16, and the other end of the spring 18 is fixedly connected to the inside of the three-way pipe 10.

[0032] Specifically, the flow deflector 16 is affected by the thrust of the airflow inside the three-way pipe 10 and the elastic force of the spring 18. When the airflow thrust is greater than the elastic force of the spring 18, the flow deflector 16 retracts, and when the airflow thrust is less than the elastic force of the spring 18, the flow deflector 16 extends.

[0033] Please see the appendix Figure 6 One end of a tension spring 25 is fixedly connected to the inside of the flue 3, and the other end of the tension spring 25 is fixedly connected to a U-shaped frame 20.

[0034] Specifically, the U-shaped frame 20 is driven to reciprocate by the elastic deformation generated by the change in flue gas pressure through the tension spring 25. When the wind force decreases, the tension spring 25 returns to its original position and pulls the U-shaped frame 20 through its connecting structure, thereby realizing the knocking operation.

[0035] Please see the appendix Figure 7 A transmission rod 21 is fixedly connected to the inner side of the U-shaped frame 20, and an irregular block 22 is provided on the outer wall of the transmission rod 21.

[0036] Specifically, the irregular block 22 has a groove inside to accommodate the movement of the transmission rod 21, thereby facilitating the transmission rod 21 to drive the irregular block 22. A disc is provided on the outside of the transmission rod 21 to prevent the irregular block 22 from falling out of the range of the transmission rod 21.

[0037] Please see the appendix Figure 7 The outer wall of the irregular block 22 is fixedly connected to a striking ball 23, and the outer wall of the striking ball 23 is set on the inner wall of the flue 3.

[0038] Specifically, by striking the inner wall of the flue pipe 3 with the rotating ball 23 along with the irregular block 22, the debris attached to the pipe wall is dislodged, preventing the pipe from accumulating scale and clogging.

[0039] Please see the appendix Figure 7 The inner part of the irregular block 22 is rotatably connected to the limiting rod 24, and the outer wall of the limiting rod 24 is fixedly connected to the outer wall of the smoke pipe 3; the outer wall of the limiting rod 24 is slidably connected to the inside of the U-shaped frame 20.

[0040] Specifically, the limiting rod 24 provides a rotation fulcrum for the irregular block 22, and the irregular block 22 has a sliding groove inside, which cooperates with the limiting rod 24 to limit the movement range of the irregular block 22.

[0041] Workflow: High-temperature flue gas is generated by burning biomass fuel in biomass boiler 1. It first enters economizer 2 to recover waste heat from the flue gas to heat boiler feedwater, improving energy utilization efficiency and reducing flue gas temperature. The cooled flue gas enters cyclone dust collector 4 through flue pipe 3 for primary dust removal, and then enters bag filter dust collector 5 to ensure the dust content of the flue gas meets the standard. The purified flue gas enters denitrification unit 6, where nitrogen oxides are removed by denitrification agent at an appropriate temperature. It then enters flue gas cooler 8 to be cooled to a suitable temperature for carbon capture, while recovering waste heat. Exhaust fan 9 creates negative pressure in the system by drawing air, driving the flue gas to flow through each device in sequence. It is then divided through three-way pipe 10. Part of the gas enters adsorption tower 14 for carbon capture through fixed cylinder 12 and booster fan 13, while the remaining gas is discharged through chimney 11.

[0042] The gas flowing inside the three-way pipe 10 is drawn through the fixed cylinder 12 by the booster fan 13, causing the impeller 153 to rotate under the action of the airflow and the connecting rod 152, thus sorting the flue gas entering the fixed cylinder 12. The gas enters the fixed cylinder 12 through the filter screen 154, which intercepts residual fine particles in the carbon capture flue gas, protecting the subsequent adsorption equipment. The knocking frame 155 and the cleaning plate 156 rotate with the connecting rod 152, thereby cleaning the surface of the filter screen 154 near the three-way pipe 10. A ball bearing is provided on the side of the striking frame 155 near the filter screen 154. The filter screen 154 has a groove inside. When the striking frame 155 moves to the groove, the ball bearing moves into the groove, thereby striking the filter screen 154 and preventing the cleaned debris from continuing to accumulate in the filter screen 154. The airflow inside the three-way pipe 10 is drawn, reducing the force on the baffle frame 16. Under the elastic force of the spring 18, the baffle frame 16 is pushed against and moves towards the fixed cylinder 12. The baffle frame 16 is guided by its inclined surface to enter the interior of the fixed cylinder 12.

[0043] When the airflow thrust inside the flue pipe 3 is less than the tension of the tension spring 25, the U-shaped frame 20 is pulled upward to reset. The transmission rod 21 drives the irregular block 22, and the limit rod 24 limits the rotation of the irregular block 22 and the movement of the U-shaped frame 20. The transmission rod 21 slides upward inside the irregular block 22, allowing the irregular block 22 to rotate under the support of the limit rod 24. The striking ball 23 strikes the inner wall of the flue pipe 3, thereby removing the debris attached to the inner wall of the flue pipe 3 during use. The removed debris enters the cyclone dust collector 4 for effective treatment, preventing blockage of the pipeline connecting the economizer 2 and the cyclone dust collector 4.

[0044] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A biomass oxygen-enriched combustion boiler flue gas system, comprising a biomass boiler (1), characterized in that: The output end of the biomass boiler (1) is connected to an economizer (2), the output end of the economizer (2) is connected to a flue (3), a cyclone dust collector (4) is installed on the outer wall of the flue (3), a bag filter (5) is connected to the inside of the cyclone dust collector (4) through a pipe, a denitrifier (6) is connected to the inside of the bag filter (5) through a pipe, a feed pipe (7) is installed inside the denitrifier (6), and a flue gas cooler (8) is connected to the output end of the denitrifier (6). The output end of the flue gas cooler (8) is equipped with an induced draft fan (9), the output end of the induced draft fan (9) is connected to a three-way pipe (10), the right side of the three-way pipe (10) is connected to a chimney (11) through a pipe, the rear side of the three-way pipe (10) is connected to a fixed cylinder (12), the outer wall of the fixed cylinder (12) is equipped with a booster fan (13), the output end of the booster fan (13) is connected to an adsorption tower (14), and the interior of the fixed cylinder (12) is provided with a flow diversion mechanism (15).

2. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 1, characterized in that: The drainage mechanism (15) includes a cross (151), the outer wall of which is fixedly connected to the inside of the fixed cylinder (12), and a connecting rod (152) is rotatably connected inside the cross (151), and an impeller (153) is fixedly connected to the outer wall of the connecting rod (152).

3. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 2, characterized in that: The outer wall of the connecting rod (152) is rotatably connected to a filter screen (154). The outer wall of the filter screen (154) is installed inside the fixed cylinder (12). The outer wall of the connecting rod (152) is fixedly connected to a striking frame (155) and a cleaning plate (156). The outer walls of the striking frame (155) and the cleaning plate (156) are both located on the outer wall of the filter screen (154).

4. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 1, characterized in that: A rectifier plate (19) is installed inside the three-way pipe (10). A flow deflector (16) is slidably connected inside the three-way pipe (10). A sleeve (17) is slidably connected to the outer wall of the flow deflector (16). The outer wall of the sleeve (17) is fixedly connected to the inside of the three-way pipe (10).

5. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 4, characterized in that: One end of a spring (18) is fixedly connected to the outer wall of the baffle (16), and the other end of the spring (18) is fixedly connected to the inside of the three-way pipe (10).

6. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 1, characterized in that: One end of the tension spring (25) is fixedly connected to the inside of the flue (3), and the other end of the tension spring (25) is fixedly connected to a U-shaped frame (20).

7. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 6, characterized in that: A transmission rod (21) is fixedly connected to the inner side of the U-shaped frame (20), and a shaped block (22) is provided on the outer wall of the transmission rod (21).

8. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 7, characterized in that: The outer wall of the irregular block (22) is fixedly connected to a striking ball (23), and the outer wall of the striking ball (23) is set on the inner wall of the flue (3).

9. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 7, characterized in that: The inner rotating connection of the irregular block (22) is a limiting rod (24), and the outer wall of the limiting rod (24) is fixedly connected to the outer wall of the smoke pipe (3).

10. The flue gas system for a biomass oxygen-enriched combustion boiler according to claim 9, characterized in that: The outer wall of the limiting rod (24) is slidably connected to the inside of the U-shaped frame (20).

Images