Pulverized coal flow equalizing device of combustor

Abstract

The utility model provides a burner pulverized coal flow equalizing device which comprises a diffusion cover, a flow equalizing cone and a supporting plate, the diffusion cover is installed on a primary air pipe and is a conical barrel-shaped component, and a flow equalizing channel for air and pulverized coal to pass through is formed. The front cover body of the diffusion cover is the air inlet end, the rear cover body of the diffusion cover is the air outlet end, the flow equalizing cone is fixed to the center of the flow equalizing channel through the supporting plate, when air and pulverized coal pass through the flow equalizing cone, airflow can be disturbed, the pulverized coal and the air are evenly dispersed in the flow equalizing channel, and scouring of the pulverized coal to the pipe wall is reduced. And the uniformly mixed pulverized coal and air are sprayed into the hearth through the combustor, so that the pulverized coal can be sufficiently combusted. According to the utility model, the front cover body, the front cone and the front plate body which are easily abraded due to impact of pulverized coal are all designed to be detachable, so that when one or more of the front cover body, the front cone and the front plate body need to be replaced due to abrasion, only damaged parts need to be detached and replaced again, undamaged parts can be continuously used, and the maintenance cost can be reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of coal powder transportation for burners, and in particular relates to a coal powder flow balancing device for burners. Background Art

[0002] Coal-fired power generation is the main form of power generation in thermal power plants. The boiler used for coal-fired power generation is called a coal-fired boiler. The pulverized coal burner is the main component of the coal-fired boiler combustion equipment. Its function is to transport pulverized coal and air into the furnace and use the heat of the coal to generate electricity.

[0003] During combustion in a coal-fired boiler, pulverized coal is introduced into the furnace through the burner nozzle along with air in a specific proportion, speed, and mixing pattern. To improve combustion efficiency and ensure more complete combustion, the air required for pulverized coal combustion is divided into primary and secondary air. The primary air, a mixture of pulverized coal and air, is introduced into the furnace, providing the oxygen required to burn the volatile components during the initial ignition of the pulverized coal. Secondary air is introduced after the pulverized coal airflow ignites, supplying the oxygen required to burn the coke and residual volatile components in the coal, ensuring complete combustion of the pulverized coal.

[0004] Pulverized coal is sprayed into the furnace through the burner along with the primary air. When the pulverized coal flows with the air in the primary air duct, it will move along the wall with the airflow, scouring the inner wall of the duct, causing wear and even wear through the inner wall of the duct. To reduce the wear of the duct, the existing technology installs a flow equalizer in the duct to create turbulence in the airflow, so that the pulverized coal is evenly distributed in the duct. On the one hand, the installation of the flow equalizer can reduce the scouring of the pulverized coal on the duct and increase the service life of the primary air duct. On the other hand, it also helps to evenly distribute the pulverized coal with the airflow, so that the pulverized coal burns more fully after being sprayed into the furnace through the burner.

[0005] At present, the burner model commonly used in coal-fired boilers in power plants is the DRB-4ZTM burner. A flow equalizer cone and a diffusion cover are installed on the primary air duct of the burner, and the flow equalizer cone is fixed by a support plate. During maintenance, it was found that the deterioration of the effect of the flow equalizer device is often due to factors such as wear of the front end of the flow equalizer cone and the front end of the diffusion cover, and wear through of the support plate, which causes the flow equalizer cone to fall off. Any problem with the above three factors will cause the flow equalizer device to fail. After the flow equalizer fails, it will not play the role of evenly mixing the coal powder, which will cause the coal powder to severely scour the primary air duct locally, and cause unstable combustion in the furnace. In the existing technology, the flow equalizer device is an integrated structure. After any part of the flow equalizer cone, diffusion cover and support plate is damaged, it needs to be replaced as a whole, which is a waste of materials and the replacement cost is also high. Utility Model Content

[0006] The utility model provides a pulverized coal flow equalizing device for a burner, aiming to solve the problem in the prior art that the flow equalizing devices are all of an integrated structure and need to be replaced as a whole if any part of the flow equalizing cone, the diffusion cover and the support plate is damaged.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is to provide a burner coal powder flow balancing device, comprising:

[0008] The diffuser cover includes a front cover body and a rear cover body, wherein the front cover body and the rear cover body are both conical cylindrical components with a narrow front and a thick rear, and the rear end of the front cover body is detachably connected to the front end of the rear cover body, and the front cover body and the rear cover body together form a flow-equalizing channel;

[0009] A flow balancing cone, comprising a front cone and a rear cone, wherein the front cone and the rear cone are respectively arranged in the flow balancing channel, and the rear end of the front cone is detachably connected to the front end of the rear cone; and

[0010] At least one support plate, the support plate includes a front plate body and a rear plate body, the rear end of the front plate body is detachably connected to the front end of the rear plate body, the rear plate body is connected between the rear cover body and the rear cone, and when there are multiple support plates, the multiple support plates are arranged at intervals along the circumference of the rear cone.

[0011] In one possible implementation, the rear end of the front cover body is provided with a first annular limiting portion, and the front end of the rear cover body is provided with a second annular limiting portion, the second limiting portion is enclosed to form a limiting groove for accommodating the first limiting portion, and the first limiting portion is snap-fitted to the limiting groove.

[0012] In one possible implementation, a first mounting hole is provided on a side of the first limiting portion adjacent to the second limiting portion, and a second mounting hole is provided on the second limiting portion axially corresponding to the first limiting portion, and the second mounting hole passes through the thickness direction of the second limiting portion. The diffuser cover also includes a first threaded fastener, which is passed through the second mounting hole and threadedly connected to the first mounting hole.

[0013] In a possible implementation, the front cone is a tapered component that is thinner at the front and thicker at the back, and the rear cone is a tapered component that is thicker at the front and thinner at the back.

[0014] In a possible implementation, the front end of the front cone is a spherical surface.

[0015] In one possible implementation, a third mounting hole is provided on the rear end face of the front cone, a fourth mounting hole is provided on the rear cone that passes through its own axial direction, and the flow equalizing cone also includes a second threaded fastener, which is passed through the fourth mounting hole and threadedly connected to the third mounting hole.

[0016] In a possible implementation, a protruding positioning portion is provided at the rear end of the front cone, and a positioning groove for accommodating the positioning portion is provided at the front end of the rear cone.

[0017] In a possible implementation, the front end of the front plate is an arc surface.

[0018] In a possible implementation, a positioning bar is provided at the rear end of the front plate, and a positioning groove for accommodating the positioning bar is provided at the front end of the rear plate.

[0019] In a possible implementation, the front cover body is used to form the side wall of the flow-balancing channel, the front cone, and at least one of the front plate body is made of silicon carbide.

[0020] Compared with the prior art, the beneficial effects of the burner coal powder flow balancing device provided by the utility model are:

[0021] The pulverized coal flow equalizing device for the burner provided by the present invention includes a diffusion hood, a flow equalizing cone and a support plate. The diffusion hood is installed on the primary air duct and is a conical cylindrical component, forming a flow equalizing channel for air and pulverized coal to pass through. The front cover body of the diffusion hood is the air inlet end, and the rear cover body is the air outlet end. The flow equalizing cone is set at the center of the flow equalizing channel and is fixed by the support plate. When the air and pulverized coal pass through the flow equalizing cone, turbulence can be generated, so that the pulverized coal and air are evenly distributed in the flow equalizing channel, and then sprayed into the furnace through the burner, which helps to fully burn. In the present invention, the front cover body, front cone and front plate body that are easily worn by the impact of pulverized coal are designed to be detachable. In this way, when one or more of them need to be replaced due to wear, only the damaged parts need to be disassembled and replaced with new ones. The undamaged parts can continue to be used, which can reduce maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the structure of a burner pulverized coal flow equalization device provided in an embodiment of the utility model;

[0023] Figure 2 An internal cross-sectional view of a burner pulverized coal flow equalizing device provided in an embodiment of the present utility model;

[0024] Figure 3 An explosion diagram of a pulverized coal flow equalizing device for a burner provided in an embodiment of the present utility model;

[0025] Figure 4 for Figure 3 A partial enlarged view of part A in the middle;

[0026] Description of reference numerals:

[0027] 1. Burner pulverized coal flow equalizing device; 10. Diffuser cover; 11. Front cover; 111. First limiting portion; 112. First mounting hole; 12. Rear cover; 121. Second limiting portion; 122. Second mounting hole; 13. First threaded fastener; 20. Flow equalizing cone; 21. Front cone; 211. Positioning portion; 22. Rear cone; 221. First positioning slot; 222. Fourth mounting hole; 23. Second threaded fastener; 30. Support plate; 31. Front plate; 311. Positioning strip; 32. Rear plate; 321. Second positioning slot; 33. Third threaded fastener; DETAILED DESCRIPTION

[0028] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] It should be noted that when an element is referred to as being "fixed to," "fixed," or "fixedly disposed" on another element, it may be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected to," "connected to" another element, it may be directly connected to the other element or there may also be an intermediate element. When an element is referred to as being "set on," "disposed on" another element, it may be directly on the other element or there may also be an intermediate element. "Multiple" refers to two or more. "At least one" refers to one or more. "Several" refers to one or more.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0031] Please also refer to Figures 1 to 4 , the burner pulverized coal flow equalizing device 1 provided in an embodiment of the present utility model is described below.

[0032] See also Figure 1The utility model provides a burner coal powder flow balancing device 1, which includes a diffusion cover 10, a flow balancing cone 20 and a support plate 30. The diffuser cover 10 includes a front cover body 11 and a rear cover body 12. Both the front cover body 11 and the rear cover body 12 are conical cylindrical components with a thin front and a thick rear. The rear end of the front cover body 11 is detachably connected to the front end of the rear cover body 12. The front cover body 11 and the rear cover body 12 together form a flow equalization channel; the flow equalization cone 20 includes a front cone 21 and a rear cone 22. The front cone 21 and the rear cone 22 are respectively arranged in the flow equalization channel, and the rear end of the front cone 21 is detachably connected to the front end of the rear cone 22; the support plate 30 includes a front plate body 31 and a rear plate body 32. The rear end of the front plate body 31 is detachably connected to the front end of the rear plate body 32, and the rear plate body 32 is connected between the rear cover body 12 and the rear cone 22. When there are multiple support plates 30, the multiple support plates 30 are arranged at intervals along the circumference of the rear cone 22.

[0033] Compared with the prior art, the beneficial effects of the burner coal powder flow equalization device 1 provided by the embodiment of the utility model are:

[0034] The burner pulverized coal flow equalization device 1 provided by the embodiment of the present invention includes a diffusion cover 10, a flow equalization cone 20 and a support plate 30. The diffusion cover 10 is installed on the primary air duct and is a conical cylindrical component, forming a flow equalization channel for air and pulverized coal to pass through. The front cover body 11 of the diffusion cover 10 is the air inlet end, and the rear cover body 12 is the air outlet end. The flow equalization cone 20 is set at the center of the flow equalization channel and is fixed by the support plate 30. When the air and pulverized coal pass through the flow equalization cone 20, turbulence can be generated, so that the pulverized coal and air are evenly distributed in the flow equalization channel, reducing the scouring of the pulverized coal on the pipe wall (especially at the bends). The evenly mixed pulverized coal and air are sprayed into the furnace through the burner, which helps to fully burn.

[0035] In the embodiment of the present utility model, the front cover 11, the front cone 21 and the front plate 31, which are easily worn by the impact of coal powder, are designed to be detachable. In this way, when one or more parts need to be replaced due to wear, it is only necessary to disassemble the damaged parts and replace them with new ones. The undamaged parts can continue to be used, which can reduce maintenance costs.

[0036] The burner flow distribution and balancing device provided in the embodiment of the present utility model is installed at the front end of the burner, wherein, in order to facilitate the maintenance and replacement of parts, the front cover body 11 and the rear cover body 12, the front cone 21 and the rear cone 22, the front plate body 31 and the rear plate body 32 are respectively detachably connected, and specifically can be achieved by screw connection, clamping fixation, etc. The rear plate body 32 is connected between the rear cover body 12 and the rear cone 22. Since the rear plate body 32, the rear cone 22 and the rear cover body 12 are not easily damaged, the rear plate body 32 and the rear cover body 12, and the rear plate body 32 and the rear cone 22 can be fixedly connected by welding or the like, and of course, a detachable connection method such as bolt fixation can also be used to achieve assembly.

[0037] The front cone 21 and the rear cone 22 are connected front and back to form a flow balancing cone 20. Flow balancing cone 20 is located at the center of the flow balancing channel. When the airflow passes through flow balancing cone 20, it creates disturbances, thereby evenly distributing the pulverized coal within the flow balancing channel. This even distribution of pulverized coal not only reduces erosion of the pipe walls, but also ensures more complete combustion when injected into the furnace through the burner.

[0038] See also Figure 1 、 Figure 2 and Figure 3 In some possible embodiments, a first annular limiting portion 111 is provided at the rear end of the front cover body 11, and a second annular limiting portion 121 is provided at the front end of the rear cover body 12. The second limiting portion 121 is enclosed to form a limiting groove for accommodating the first limiting portion 111, and the first limiting portion 111 is snap-fitted into the limiting groove.

[0039] In this embodiment, the first limiting portion 111 and the second limiting portion 121 are snap-fitted and adapted, and the limiting groove can be positioned when the front cover 11 is installed to ensure accurate positioning of the front cover 11. In order to prevent air leakage between the first limiting portion 111 and the second limiting portion 121, the joint surface between the two can also be coated with sealant or provided with a sealing ring, sealing gasket, etc.

[0040] See also Figures 1 to 3 In some possible embodiments, a first mounting hole 112 is provided on a side of the first limiting portion 111 adjacent to the second limiting portion 121, and a second mounting hole 122 is provided on the second limiting portion 121 axially corresponding to the first limiting portion 111. The second mounting hole 122 passes through the thickness direction of the second limiting portion 121. The diffuser 10 also includes a first threaded fastener 13, which is passed through the second mounting hole 122 and is threadedly connected to the first mounting hole 112.

[0041] In this embodiment, the first limiting portion 111 and the second limiting portion 121 are detachably connected by the first threaded fastener 13, which is convenient for installation and removal. The first threaded fastener 13 can be a screw, bolt, stud, etc., and one or more can be provided as needed.

[0042] See also Figure 2 and Figure 3 In some possible embodiments, the front cone 21 is a tapered member that is tapered at the front and wide at the rear, while the rear cone 22 is a tapered member that is wide at the front and tapered at the rear. The front cone 21 and the rear cone 22 form a spindle-shaped structure, whose shape conforms to an aerodynamic design. There are no restrictions on the taper and size of the front cone 21 and the rear cone 22, and the user can set them according to their needs.

[0043] See also Figure 1 、 Figure 2 and Figure 3In some possible embodiments, the front end of the front cone 21 is spherical, which can guide the airflow, thereby reducing air flow resistance and coal powder impact force, and extending the service life of the front cone 21.

[0044] See also Figure 2 and Figure 3 In some possible embodiments, a third mounting hole is defined on the rear end surface of the front cone 21, and a fourth mounting hole 222 is defined on the rear cone 22, extending axially therethrough. The flow equalizing cone 20 further includes a second threaded fastener 23, which passes through the fourth mounting hole 222 and is threadedly connected to the third mounting hole. The second threaded fastener 23 can be a long stud, bolt, or the like. The second threaded fastener 23 is installed at the rear end of the rear cone 22, on the leeward side, where it is less susceptible to impact from coal dust and less susceptible to damage.

[0045] See also Figures 2 to 4 In some possible embodiments, a protruding positioning portion 211 is provided at the rear end of the front cone 21, and a first positioning groove 221 for accommodating the positioning portion 211 is provided at the front end of the rear cone 22. The positioning portion 211 and the first positioning groove 221 are snap-fitted to facilitate the installation and positioning of the front cone 21.

[0046] See also Figure 3 and Figure 4 In some possible embodiments, the front end of the front plate 31 is an arc surface, which can reduce air flow resistance and the impact force of coal powder, and extend the service life of the front plate 31.

[0047] See also Figure 4 In some possible embodiments, a positioning bar 311 is provided at the rear end of the front plate 31, and a second positioning slot 321 is provided at the front end of the rear plate 32 for receiving the positioning bar 311, thereby facilitating the installation and positioning of the front plate 31. The front plate 31 and the rear plate 32 are connected by a third threaded fastener 33, making installation and removal easy.

[0048] In some possible embodiments, the front cover 11 is used to form the side wall of the flow-equalizing channel, the front cone 21, and at least one of the front plate 31 are made of silicon carbide, which has good wear resistance and can be used for a long time without damage. The rear cover 12, the rear cone 22 and the rear plate 32 can be made of relatively cheap ordinary wear-resistant steel, which not only improves the wear resistance but also helps to reduce manufacturing costs.

[0049] It can be understood that the various parts in the above embodiments can be freely combined or deleted to form different combination embodiments. The specific contents of each combination embodiment will not be repeated here. After this description, it can be considered that the specification of the utility model has recorded various combination embodiments and can support different combination embodiments.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A burner coal powder flow equalization device, characterized in that: include: The diffuser cover includes a front cover body and a rear cover body, wherein the front cover body and the rear cover body are both conical cylindrical components with a narrow front and a thick rear, and the rear end of the front cover body is detachably connected to the front end of the rear cover body, and the front cover body and the rear cover body together form a flow-equalizing channel; A flow balancing cone, comprising a front cone and a rear cone, wherein the front cone and the rear cone are respectively arranged in the flow balancing channel, and the rear end of the front cone is detachably connected to the front end of the rear cone; and At least one support plate, the support plate includes a front plate body and a rear plate body, the rear end of the front plate body is detachably connected to the front end of the rear plate body, the rear plate body is connected between the rear cover body and the rear cone, and when there are multiple support plates, the multiple support plates are arranged at intervals along the circumference of the rear cone.

2. The burner pulverized coal flow equalizing device according to claim 1, characterized in that: The rear end of the front cover is provided with an annular first limiting portion, and the front end of the rear cover is provided with an annular second limiting portion. The second limiting portion is enclosed to form a limiting groove for accommodating the first limiting portion, and the first limiting portion is snap-fitted with the limiting groove.

3. The burner pulverized coal flow equalizing device according to claim 2, characterized in that: A first mounting hole is provided on a side of the first limiting portion adjacent to the second limiting portion, and a second mounting hole is provided on the second limiting portion axially corresponding to the first limiting portion, and the second mounting hole passes through the thickness direction of the second limiting portion. The diffuser cover also includes a first threaded fastener, which is passed through the second mounting hole and threadedly connected to the first mounting hole.

4. The burner pulverized coal flow equalizing device according to claim 1, characterized in that: The front cone is a tapered component that is thin at the front and thick at the back, and the rear cone is a tapered component that is thick at the front and thin at the back.

5. The burner pulverized coal flow equalizing device according to claim 1 or 4, characterized in that: The front end of the front cone is a spherical surface.

6. The burner pulverized coal flow equalizing device according to claim 1 or 4, characterized in that: The rear end face of the front cone is provided with a third mounting hole, the rear cone is provided with a fourth mounting hole running through its own axial direction, and the flow equalizing cone also includes a second threaded fastener, which is passed through the fourth mounting hole and threadedly connected to the third mounting hole.

7. The burner pulverized coal flow equalizing device according to claim 1 or 4, characterized in that: A protruding positioning portion is provided at the rear end of the front cone, and a first positioning groove for accommodating the positioning portion is provided at the front end of the rear cone.

8. The burner pulverized coal flow equalizing device according to claim 1, characterized in that: The front end of the front plate is an arc surface.

9. The burner pulverized coal flow equalizing device according to claim 1, characterized in that: A positioning strip is provided at the rear end of the front plate, and a second positioning groove for accommodating the positioning strip is provided at the front end of the rear plate.

10. The burner pulverized coal flow equalizing device according to claim 1, characterized in that: The front cover is used to form the side wall of the flow-balancing channel, the front cone, and at least one of the front plate is made of silicon carbide.

Images