Secondary air distribution device for circulating fluidized bed boiler

Abstract

The present application discloses a secondary air distribution device for a circulating fluidized bed boiler, comprising: a boiler assembly, which comprises a secondary air duct; an air heat exchanger, which is connected to the secondary air duct through a first air duct; a fan, which comprises a casing and an air outlet, the air outlet is connected to the air heat exchanger through a second air duct, the air outlet is located on the casing, the air outlet is provided with a rectangular frame, and a plurality of one-way air outlet holes are provided on the top of the rectangular frame; a buffer vibration reduction assembly, which is arranged on the inner wall of the casing and located on one side of the air outlet, the buffer vibration reduction assembly comprises a first mounting seat, a first spring, a slider and a buffer plate, the first mounting seat is provided with a first cavity, the slider slides in the first cavity, the slider is connected to the buffer plate through a first connecting rod, the first spring is located in the first cavity, the first spring abuts against the slider, the buffer plate is located on one side of the air outlet, the first cavity is connected to the rectangular frame through a first connecting pipe, and the pipe mouth of the first connecting pipe is located on the inner side wall of the first mounting seat. Thus, the noise of the fan is reduced.

Description

Technical Field

[0001] The present invention generally relates to the technical field of circulating fluidized bed boilers, and in particular to a secondary air distribution device for a circulating fluidized bed boiler. Background Art

[0002] The circulating fluidized bed boiler adopts fluidized combustion, and its internal flow is mainly divided into the flow of the lower dense phase area and the flow of the upper dilute phase area. The lower dense phase area, namely the cone section, is the main place where combustion occurs; the air volume is supplied by graded air supply, and the primary air is supplied by the air distribution plate at the bottom of the furnace, which plays the role of fluidization and combustion air supply; the secondary air is supplied by the wall nozzles at different heights in the lower dense phase area of ​​the furnace to supplement the oxygen required for combustion. Therefore, the timely supply of secondary air has a great influence on the combustion efficiency of the boiler. Generally, fans are used to distribute the secondary air to the circulating fluidized bed boiler.

[0003] In the prior art, the fan may generate turbulent airflow and reflected airflow during operation, causing the fan to generate relatively loud noise. Summary of the invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a secondary air distribution device for a circulating fluidized bed boiler that reduces noise.

[0005] In a first aspect, the secondary air distribution device for a circulating fluidized bed boiler of the present invention comprises:

[0006] a boiler assembly including a secondary air duct;

[0007] an air heat exchanger connected to the secondary air duct via a first air duct;

[0008] A fan, comprising a casing and an air outlet, wherein the air outlet is connected to the air heat exchanger through a second air duct, the air outlet is located on the casing, the air outlet is provided with a rectangular frame, and a plurality of one-way air outlet holes are provided on the top of the rectangular frame;

[0009] A buffer and vibration-absorbing component is arranged on the inner wall of the casing and located on one side of the air outlet. The buffer and vibration-absorbing component includes a first mounting seat, a first spring, a slider and a buffer plate. The first mounting seat is provided with a first cavity. The slider slides in the first cavity. The slider is connected to the buffer plate through a first connecting rod. The first spring is located in the first cavity. The first spring resists the slider. The buffer plate is located on one side of the air outlet. The first cavity is connected to the rectangular frame through a first connecting pipe. The pipe mouth of the first connecting pipe is located on the inner wall of the first mounting seat.

[0010] According to the technical solution provided in the embodiment of the present application, when the fan generates turbulent airflow and reflected airflow, the buffer plate can weaken the turbulent airflow and reflected airflow, thereby reducing the noise of the fan. In the process of the buffer plate weakening the turbulent airflow and reflected airflow, the turbulent airflow and reflected airflow will push the buffer plate to move and compress the first spring. The first spring can reduce the impact of the turbulent airflow and reflected airflow on the buffer plate. In the process of the turbulent airflow and reflected airflow pushing the buffer plate to move, when the slider slides to the position where the pipe mouth of the first connecting pipe is exposed, the airflow can enter the rectangular frame through the first connecting pipe and be discharged into the second air duct from the one-way air outlet on the rectangular frame, thereby increasing the air supply volume and air distribution effect of the fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0012] Figure 1 It is a structural schematic diagram of a secondary air distribution device for a circulating fluidized bed boiler according to an embodiment of the present invention;

[0013] Figure 2 A schematic structural diagram of a fan for a secondary air distribution device of a circulating fluidized bed boiler according to an embodiment of the present invention;

[0014] Figure 3 for Figure 2 A partial enlarged view of the middle A;

[0015] Figure 4 A schematic structural diagram of a fan for a secondary air distribution device of a circulating fluidized bed boiler according to an embodiment of the present invention;

[0016] Figure 5 for Figure 4 A partial enlarged view of point B in the middle;

[0017] Figure 6 A schematic structural diagram of a fan for a secondary air distribution device of a circulating fluidized bed boiler according to an embodiment of the present invention;

[0018] Figure 7 It is a schematic structural diagram of an air outlet of a fan of a secondary air distribution device for a circulating fluidized bed boiler according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0020] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0021] Please refer to Figures 1 to 7 The secondary air distribution device for a circulating fluidized bed boiler of the present invention comprises: a boiler assembly 100, which comprises a secondary air duct 110; an air heat exchanger 200, which is connected to the secondary air duct 110 through a first air duct 210; a fan 300, which comprises a casing 310 and an air outlet 320, the air outlet 320 is connected to the air heat exchanger 200 through a second air duct 220, the air outlet 320 is located on the casing 310, the air outlet 320 is provided with a rectangular frame 400, and a plurality of one-way air outlet holes 410 are provided on the top of the rectangular frame 400; a buffer vibration reduction assembly 500, which is arranged on the inner wall of the casing 310 and is located at the air outlet 320. On the side, the buffer and vibration-absorbing assembly 500 includes a first mounting seat 510, a first spring 520, a slider 530 and a buffer plate 540. The first mounting seat 510 is provided with a first cavity 511. The slider 530 slides in the first cavity 511. The slider 530 is connected to the buffer plate 540 through a first connecting rod 550. The first spring 520 is located in the first cavity 511. The first spring 520 resists the slider 530. The buffer plate 540 is located on one side of the air outlet 320. The first cavity 511 is connected to the rectangular frame 400 through a first connecting pipe 512. The pipe mouth of the first connecting pipe 512 is located on the inner wall of the first mounting seat 510.

[0022] In the embodiment of the present invention, the fan 300 delivers air to the air heat exchanger 200 through the second air duct 220, and the air heat exchanger 200 heats the air. The heated air enters the secondary air duct 110 through the first air duct 210, and then enters the boiler assembly 100, realizing secondary air supply.

[0023] The fan 300 includes a housing 310 and an air outlet 320. Of course, the fan 300 also includes an impeller 330, a rotating shaft 340 and a motor 350. The motor 350 drives the impeller 330 to rotate in the housing 310 through the rotating shaft 340. The impeller 330 sucks in the air outside the fan 300, and the air in the fan 300 moves along the inner wall of the housing 310 to the air outlet 320, and then flows out of the fan 300 from the air outlet 320. Usually, the air in the air outlet 320 moves in a direction perpendicular to the air outlet 320. The fan 300 may generate turbulent airflow and reflected airflow during operation, that is, the turbulent airflow and reflected airflow in the fan 300 do not move in a direction perpendicular to the air outlet 320, so that the fan 300 generates a large noise. At the same time, the turbulent airflow and reflected airflow will also impact the inner wall of the housing 310. Usually, the turbulent airflow and reflected airflow will move along the circumference of the housing 310.

[0024] When the fan 300 generates turbulent airflow and reflected airflow, the buffer plate 540 is located on the movement path of the turbulent airflow and reflected airflow, and the buffer plate 540 can weaken the turbulent airflow and reflected airflow, thereby reducing the noise of the fan 300. In the process of the buffer plate 540 weakening the turbulent airflow and reflected airflow, the turbulent airflow and reflected airflow will push the buffer plate 540 to move, compressing the first spring 520, and the first spring 520 can reduce the impact of the turbulent airflow and reflected airflow on the buffer plate 540. In the process of the turbulent airflow and reflected airflow pushing the buffer plate 540 to move, when the slider 530 slides to the position where the pipe opening of the first connecting pipe 512 is exposed, the airflow can enter the rectangular frame 400 through the first connecting pipe 512, and be discharged into the second air duct 220 from the one-way air outlet 410 on the rectangular frame 400, thereby increasing the air supply volume and air distribution effect of the fan 300. Of course, the buffer plate 540 can be set to be an arc shape, and the buffer plate 540 is located on one side of the air outlet 320. When the turbulent airflow and the reflected airflow come into contact with the buffer plate 540, the buffer plate 540 can guide part of the turbulent airflow and the reflected airflow to the air outlet 320, so that part of the turbulent airflow and the reflected airflow flows out of the fan 300 from the air outlet 320, thereby increasing the air supply and wind distribution effect of the fan 300.

[0025] Furthermore, the buffer and vibration-absorbing assembly 500 also includes a second mounting seat 560, a second spring 570, a first slide plate 580 and a reverse thrust assembly 600. The air outlet 320 is located on the second mounting seat 560. The second mounting seat 560 is provided with a second cavity 561. The reverse thrust assembly 600 is located above the air outlet 320. The first slide plate 580 and the second spring 570 are located in the second cavity 561. The reverse thrust assembly 600 is fixedly connected to the first slide plate 580 through multiple first guide rods 581. The second spring 570 is located on the side of the first slide plate 580 that is away from the reverse thrust assembly 600. The second cavity 561 is connected to the first cavity 511 through a second connecting pipe 562.

[0026] In an embodiment of the present invention, the pipe mouth of the second connecting pipe 562 is always located on the side of the first slide plate 580 facing away from the reverse thrust assembly 600. The air outlet 320 is set on the second mounting seat 560, and the reverse thrust assembly 600 is fixedly connected to the first slide plate 580 through a plurality of first guide rods 581, and the second spring 570 supports the first slide plate 580. When the boiler assembly 100 has reverse wind pressure, the air is pushed in the reverse direction from the air outlet 320 into the casing 310 to form a reverse airflow. At this time, the reverse airflow pushes the reverse thrust assembly 600 to approach the second mounting seat 560, and the second mounting seat 560 drives the first slide plate 580 to move, and the first slide plate 580 compresses the second spring 570. The second spring 570 is deformed to buffer the impact on the reverse thrust assembly 600. The first slide plate 580 moves in the second cavity 561 to compress the air in the second cavity 561, and the air in the second cavity 561 enters the first cavity 511 through the second connecting pipe 562. The air pressure in the first cavity 511 increases, and the air in the first cavity 511 enters the rectangular frame 400 through the first connecting pipe 512, and then is ejected from the one-way air outlet 410 on the rectangular frame 400, forming an airflow in the opposite direction to the reverse airflow, counteracting the reverse airflow, weakening the reverse airflow, and reducing the impact of the reverse airflow on the fan 300.

[0027] Furthermore, the reverse thrust assembly 600 includes a third mounting seat 610, a third spring 620, a second slide plate 630 and a reverse thrust plate 640. The third mounting seat 610 is provided with a third cavity 611. The third spring 620 and the second slide plate 630 are located in the third cavity 611. A gap is provided between the third mounting seat 610 and the air outlet 320. The reverse thrust plate 640 is located on the side of the third mounting seat 610 that is away from the air outlet 320. The reverse thrust plate 640 is fixedly connected to the second slide plate 630 through a plurality of second guide rods 631. The third spring 620 is located on the side of the second slide plate 630 that is away from the reverse thrust plate 640. The second cavity 561 is connected to the third cavity 611 through a third connecting pipe 612.

[0028] In the embodiment of the present invention, the pipe mouth of the third connecting pipe 612 is always located on the side of the second slide plate 630 facing away from the reverse thrust plate 640. When the boiler assembly 100 has reverse wind pressure, the air is pushed in the reverse direction from the air outlet 320 into the housing 310 to form a reverse airflow. At this time, the reverse airflow pushes the reverse thrust plate 640 to approach the third mounting seat 610, and the third mounting seat 610 drives the second slide plate 630 to move, and the second slide plate 630 compresses the third spring 620. The third spring 620 is deformed to buffer the impact on the reverse thrust plate 640. The second slide plate 630 moves in the third cavity 611, compresses the air in the third cavity 611, and the air in the third cavity 611 enters the second cavity 561 through the third connecting pipe 612. The air pressure in the second cavity 561 increases, and the air in the second cavity 561 enters the first cavity 511 through the second connecting pipe 562. The air pressure in the first cavity 511 increases, and the air in the first cavity 511 enters the rectangular frame 400 through the first connecting pipe 512, and then is ejected from the one-way air outlet 410 on the rectangular frame 400, forming an airflow in the opposite direction to the reverse airflow, counteracting the reverse airflow, weakening the reverse airflow, and reducing the impact of the reverse airflow on the fan 300.

[0029] Furthermore, a triangular guide block 613 is fixedly connected to one side of the third mounting seat 610 facing the air outlet 320 .

[0030] In the embodiment of the present invention, the reverse thrust assembly 600 is located downstream of the air outlet 320, that is, when the fan 300 is working normally, the air first flows out of the air outlet 320 and then contacts the reverse thrust assembly 600. A triangular guide block 613 is fixedly connected to the side of the third mounting seat 610 facing the air outlet 320, which facilitates the air to flow out of the air outlet 320 and reduces the interference of the reverse thrust assembly 600 on the air flow.

[0031] Furthermore, the fan 300 includes an impeller 330 , a rotating shaft 340 and a motor 350 . The impeller 330 is rotatably connected to the housing 310 , and the motor 350 drives the impeller 330 to rotate via the rotating shaft 340 .

[0032] In the embodiment of the present invention, the motor 350 drives the impeller 330 to rotate in the housing 310 via the rotating shaft 340. The impeller 330 draws in air outside the fan 300, and the air in the fan 300 moves along the inner wall of the housing 310 to the air outlet 320, and then flows out of the fan 300 from the air outlet 320.

[0033] Furthermore, the casing 310 is fixedly connected with a deflector 360 , the deflector 360 is fixedly connected with a filter 361 , the filter 361 is provided with a heat-conducting tube 362 , the heat-conducting tube 362 is connected with a heat-conducting wire 363 , and the heat-conducting wire 363 is connected to the air heat exchanger 200 .

[0034] In the embodiment of the present invention, the motor 350 drives the impeller 330 to rotate in the housing 310 through the rotating shaft 340. The impeller 330 sucks in the air outside the fan 300, and the air outside the fan 300 enters the fan 300 through the filter 361. The filter 361 can filter the air, ensure the quality of the air entering the fan 300, prevent external dust from entering the fan 300, the air heat exchanger 200 and the secondary air duct 110, so as to reduce the content of particulate matter and impurities therein, thereby reducing the wear on the internal heating surface of the boiler assembly 100 and improving the penetration effect of the secondary air.

[0035] The filter 361 is provided with a heat-conducting tube 362, which can preheat the air passing through the filter 361. When the temperature difference between the inside and outside of the fan 300 is large, the impact of cold air on the fan 300 is reduced. The heat-conducting tube 362 is connected to the air heat exchanger 200 through the heat-conducting wire 363, and the heat of the air heat exchanger 200 is transferred to the heat-conducting tube 362 through the heat-conducting wire 363, that is, the air heat exchanger 200 heats the heat-conducting tube 362 through the heat-conducting wire 363.

[0036] Furthermore, the heat conductive wire 363 is externally coated with a heat insulating layer.

[0037] In the embodiment of the present invention, the heat insulation layer can reduce the flow of heat on the heat conductive wire 363 , thereby ensuring the heat conductive effect of the heat conductive wire 363 .

[0038] Furthermore, it also includes a cleaning component 700, which includes a cleaning brush 710 and a connecting rod 720, the connecting rod 720 is fixedly connected to the impeller 330, one end of the cleaning brush 710 is fixedly connected to the connecting rod 720, and the other end of the cleaning brush 710 is rotatably connected to the air guide cover 360.

[0039] In an embodiment of the present invention, the impeller 330 rotates, driving the cleaning brush 710 to rotate through the connecting rod 720. The cleaning brush 710 cleans the filter 361 online to prevent the filter 361 from being blocked after long-term use, thereby affecting the filtering effect of the filter 361 and preventing the air supply efficiency of the fan 300 from being affected.

[0040] Furthermore, the cleaning assembly 700 includes two cleaning brushes 710 , and the two cleaning brushes 710 are located on both sides of the filter 361 .

[0041] In the embodiment of the present invention, one end of the two cleaning brushes 710 is fixedly connected to the connecting rod 720, and the other end of the two cleaning brushes 710 is rotatably connected to the air guide cover 360, and the impeller 330 drives the two cleaning brushes 710 to rotate synchronously through the connecting rod 720. In addition, the two cleaning brushes 710 are located on both sides of the filter 361, and the two cleaning brushes 710 clean both sides of the filter 361 synchronously, thereby ensuring the cleaning effect of the filter 361.

[0042] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with (but not limited to) technical features with similar functions disclosed in the present application.

Claims

1. A secondary air distribution device for a circulating fluidized bed boiler, characterized in that: include: a boiler assembly including a secondary air duct; an air heat exchanger connected to the secondary air duct via a first air duct; A fan, comprising a casing and an air outlet, wherein the air outlet is connected to the air heat exchanger through a second air duct, the air outlet is located on the casing, the air outlet is provided with a rectangular frame, and a plurality of one-way air outlet holes are provided on the top of the rectangular frame; A buffer vibration-absorbing component, which is arranged on the inner wall of the casing and located at one side of the air outlet, the buffer vibration-absorbing component includes a first mounting seat, a first spring, a slider and a buffer plate, the first mounting seat is provided with a first cavity, the slider slides in the first cavity, the slider is connected to the buffer plate through a first connecting rod, the first spring is located in the first cavity, the first spring resists the slider, the buffer plate is located at one side of the air outlet, the first cavity is connected to the rectangular frame through a first connecting pipe, the pipe mouth of the first connecting pipe is located at the inner side wall of the first mounting seat, the buffer vibration-absorbing component also includes a second mounting seat, a second spring, a first slide plate and a reverse thrust component, the air outlet is located on the second mounting seat, the second mounting seat is provided with a second cavity, the reverse thrust component is located above the air outlet, the first slide plate and the second spring are located in the second cavity, the reverse thrust component is fixedly connected to the first slide plate through a plurality of first guide rods, the second spring is located on the side of the first slide plate facing away from the reverse thrust component, and the second cavity is connected to the first cavity through a second connecting pipe.

2. The secondary air distribution device for a circulating fluidized bed boiler according to claim 1, characterized in that: The reverse thrust assembly comprises a third mounting seat, a third spring, a second slide plate and a reverse thrust plate. The third mounting seat is provided with a third cavity. The third spring and the second slide plate are located in the third cavity. A gap is provided between the third mounting seat and the air outlet. The reverse thrust plate is located on the side of the third mounting seat facing away from the air outlet. The reverse thrust plate is fixedly connected to the second slide plate through a plurality of second guide rods. The third spring is located on the side of the second slide plate facing away from the reverse thrust plate. The second cavity is connected to the third cavity through a third connecting pipe.

3. The secondary air distribution device for a circulating fluidized bed boiler according to claim 2, characterized in that: A triangular guide block is fixedly connected to one side of the third mounting seat facing the air outlet.

4. The secondary air distribution device for a circulating fluidized bed boiler according to claim 1, characterized in that: The fan comprises an impeller, a rotating shaft and a motor. The impeller is rotatably connected to the casing, and the motor drives the impeller to rotate via the rotating shaft.

5. The secondary air distribution device for a circulating fluidized bed boiler according to claim 4, characterized in that: The casing is fixedly connected with a flow guide cover, the flow guide cover is fixedly connected with a filter screen, the filter screen is provided with a heat conduction tube, the heat conduction tube is connected with a heat conduction wire, and the heat conduction wire is connected to the air heat exchanger.

6. The secondary air distribution device for a circulating fluidized bed boiler according to claim 5, characterized in that: The heat conducting wire is coated with a heat-insulating layer on the outside.

7. The secondary air distribution device for a circulating fluidized bed boiler according to claim 5, characterized in that: It also includes a cleaning component, which includes a cleaning brush and a connecting rod. The connecting rod is fixedly connected to the impeller, one end of the cleaning brush is fixedly connected to the connecting rod, and the other end of the cleaning brush is rotatably connected to the deflector.

8. The secondary air distribution device for a circulating fluidized bed boiler according to claim 7, characterized in that: The cleaning assembly includes two cleaning brushes, and the two cleaning brushes are located on both sides of the filter.

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