Feeding device of biomass circulating fluidized bed boiler
By designing the feeding device of the biomass circulating fluidized bed boiler, the problems of blockage in the boiler during the feeding process, the problems of blockage in the water-cooled wall connection are solved, and the flue gas backflow is blocked, so as to achieve smooth feeding, preventing blockage and flue gas backflow, ensuring the safe and stable operation of the boiler.
Patent Information
- Application Number
- CN202323273278.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-01
- Publication Date
- 2025-02-28
- Estimated Expiration
- 2033-12-01
AI Technical Summary
During the feeding process of biomass circulating fluidized bed boilers, it is easy to cause blockage, difficulty in the blockage, water-cooled wall connection expansion is blocked, and flue gas backflow is affected, affecting the safe and stable operation of the boiler.
A biomass circulating fluidized bed boiler feeding device is designed, including the water-cooled wall of the boiler, a feeder, a feeding trough and a cover. It adopts a square or circular cross-sectional structure of the feeding pipe, equipped with sealed air and feeding air devices, the discharge section uses wear-resistant and high-temperature alloy materials, and an expansion groove and a removable sealing cover are provided at the connection.
It achieves smooth feeding, prevents the backflow of blocked materials and flue gases, ensures free expansion at the connection of water-cooled walls, extends the service life of the feeding device, and ensures the safe and stable operation of the boiler.
Smart Images
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Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of thermal energy engineering, in particular to a feeding device for a biomass circulating fluidized bed boiler. Background Art
[0002] Circulating fluidized bed boiler is a clean combustion equipment with a good commercialization degree and wide application. In recent years, it has been used more and more in the field of biomass fuel combustion. Due to the high moisture content and low density of biomass fuel, the feed volume per unit mass of fuel is large. In addition, the structure of circulating fluidized bed boiler itself is relatively compact and the feeding space is relatively limited. When the fuel is fed into the furnace, it is easy to get blocked, the connection with the water-cooled wall is blocked, and the connection is easy to crack. The phenomenon of flue gas backflow also occurs from time to time, which seriously affects the safe and stable operation of the boiler. Utility Model Content
[0003] The utility model aims to solve the technical problems existing in the prior art and provides a feeding device for a biomass circulating fluidized bed boiler.
[0004] To achieve the above purpose, the utility model provides a technical solution: a biomass circulating fluidized bed boiler feeding device, comprising a water-cooled wall, a feeder, a feeding trough and a cover shell of the boiler, the feeding trough and the feeder are connected through a connecting elbow, an expansion joint and a detachable sealing cover plate are arranged above the connecting elbow, the feeding trough and the upper part of the water-cooled wall are connected through a fixing device, and the feeding trough and the lower part of the water-cooled wall are connected through a cover shell;
[0005] The feed trough includes a feed pipe, a sealing air device, and a material spreading air device. The feed pipe includes a feed section, a feed section and a discharge section. The discharge section is provided with a material viewing device. The feed section is vertically downward, the feed section is inclined downward, and the inclination angle is 65 degrees. The angle between the discharge section and the feed section is 0 to 15 degrees. A feed interface is provided at the connection between the feed section and the feed section, and the material of the discharge section is alloy material.
[0006] Preferably, the cross section of the feed conveying pipe is circular, polygonal or rectangular, and the area of the cross section of the feed conveying pipe gradually increases from top to bottom or remains unchanged.
[0007] Preferably, the sealed air device includes a sealed air duct seat, a sealed air chamber, a sealed air nozzle and a orifice plate; a flange is provided on the feed section, and a sealed air interface is provided on the flange; the sealed air chamber is connected to the sealed air interface, the sealed air interface is connected to the sealed air nozzle and the orifice plate, and the sealed air nozzle and the orifice plate extend into the feed section.
[0008] Preferably, the broadcasting air device includes a broadcasting air duct seat, a broadcasting air chamber, a broadcasting air nozzle and a orifice plate, a broadcasting air interface is provided on the feeding section, the broadcasting air chamber is connected to the broadcasting air interface, the broadcasting air interface is connected to the broadcasting air nozzle and the orifice plate, and the broadcasting air nozzle and the orifice plate extend into the feeding section.
[0009] Preferably, the material viewing device consists of a tube cap, heat-resistant glass and a threaded tube.
[0010] Preferably, the fixing device is composed of long and short hooks, a loose nut and an ear plate.
[0011] Preferably, the casing comprises a casing panel, a connecting plate and expansion slots, the connecting plate is an L-shaped plate or a comb-shaped plate, and a certain number of expansion slots are evenly assembled at the connection between the casing and the water-cooled wall.
[0012] Preferably, the discharge section can be installed in the negative pressure zone or the positive pressure zone; when the discharge section is installed in the negative pressure zone, the sealing wind is 1-2% to prevent bed pressure fluctuations and ensure sealing; when the discharge section is installed in the positive pressure zone, the sealing wind uses recycled flue gas, so that the pressure head of the discharge section is greater than the bed pressure to prevent flue gas backflow and ensure sealing.
[0013] Beneficial effects of the utility model:
[0014] 1. Feeding is smooth. Since it adopts a square or round cross-sectional structure and the cross-sectional size remains unchanged or gradually increases, it is not easy to get blocked.
[0015] 2. There are means to clear the blockage, because a movable sealable cover is installed at the interface between the feed trough and the feeder. Once an accidental blockage occurs, it can be cleared by round steel or steel chisel;
[0016] 3. Effectively prevent flue gas from flowing back. By sealing air and recycling flue gas, the pressure of the discharge section is greater than the flue gas pressure in the furnace, effectively blocking the furnace flue gas from flowing back into the feeding device;
[0017] 4. To prevent expansion obstruction at the water-cooled wall connection, the upper part of the feeder is connected to the adjusting and fixing device through a loose nut, and an expansion groove is installed at the lower part where it is welded to the water-cooled wall, so that the feeder can expand freely upward relative to the water-cooled wall, and the thermal stress can be effectively released along the joint surface of the water-cooled wall, solving the problem of expansion obstruction and easy cracking at the joint of the water-cooled wall;
[0018] 5. The discharging section will not crack. Since the discharging end is made of wear-resistant, high-temperature-resistant and fatigue-resistant alloy steel, it is moisture-resistant, wear-resistant, high-temperature-resistant and corrosion-resistant, and will not crack, effectively extending the service life of the feeding device.
[0019] The feeding device of the biomass circulating fluidized bed boiler is more suitable for various working conditions of biomass fuel feeding, especially for high-humidity, high-corrosion, and high-abrasive biomass fuels (such as furfural residue, sludge, livestock manure, solid waste and other fuels). It has a high tolerance and adaptability, and can effectively prevent problems such as poor feeding, structural expansion obstruction or even cracking, and flue gas backflow, laying the foundation for the stable and continuous operation of the biomass circulating fluidized bed boiler. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.
[0021] Figure 1 This is the main view of the overall structure of the utility model;
[0022] Figure 2 It is a side view of the overall structure of the utility model;
[0023] Figure 3 It is a top view of the overall structure of the utility model;
[0024] Figure 4 It is a schematic diagram of the structure of the sealing air nozzle and orifice plate and the broadcasting air nozzle and orifice plate of the utility model;
[0025] Figure 5 This is a schematic diagram of the cover structure of the utility model;
[0026] Figure 6 This is a schematic diagram of the expansion tank structure of the utility model;
[0027] Figure 7 It is a structural schematic diagram of the material viewing device of the utility model.
[0028] Figure annotation:
[0029] 1-solidification device, 2-feeding interface, 3-sealing air interface, 4-broadening air interface, 5-broadening air nozzle, 6-material viewing device, 7-cover, 8-expansion joint, 9-sealing cover plate, 10-feeder 11-sealing air nozzle. DETAILED DESCRIPTION
[0030] This section will describe in detail the specific embodiments of the utility model. The preferred embodiments of the utility model are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the utility model, but it cannot be understood as a limitation on the protection scope of the utility model.
[0031] The utility model provides a feeding device for a biomass circulating fluidized bed boiler, which effectively solves the problems of material blocking and smoke backflow in the biomass circulating fluidized bed boiler, ensures smooth feeding, and adds a guarantee for safe and stable operation of the boiler.
[0032] Reference Figure 1-Figure 3The preferred embodiment of the utility model is a feeding device of a biomass circulating fluidized bed boiler, comprising a water-cooled wall of the boiler, a feeder 10, a feed trough and a cover 7; the feed trough is connected to the feeder 10 through a connecting elbow, an expansion joint 8 and a detachable sealing cover plate 9 are arranged above the connecting elbow, the feed trough and the upper part of the water-cooled wall are connected through a fixing device 1, and the fixing device 1 includes a long and short draw hook, a loose nut and an ear plate; the feed trough is connected to the lower part of the water-cooled wall through a cover 7, and the cover 7 is as shown Figure 5 As shown, the housing 7 includes a housing panel, a connecting plate and an expansion slot. The connecting plate is an L-shaped plate or a comb-shaped plate. A certain number of expansion slots are evenly installed at the connection between the housing 7 and the water-cooled wall. Figure 6 As shown, ensure that the thermal stress at the connection is effectively released.
[0033] The feed trough includes a feed pipe, a sealing air device, a material broadcasting air device, and a material viewing device 6. The material viewing device 6 is as follows: Figure 7 As shown, the material viewing device 6 is composed of a pipe cap, heat-resistant glass and a threaded pipe.
[0034] The conveying pipe includes a feeding section, a conveying section and a discharging section. The cross-section of the conveying pipe is circular, polygonal or rectangular, preferably rectangular. The area of the cross-section of the conveying pipe increases from top to bottom or remains unchanged; the feeding section is vertically downward, the conveying section is inclined downward, and the inclination angle is 65 degrees, and the angle between the discharging section and the conveying section is 0 to 15 degrees; a conveying interface 2 is provided at the connection between the feeding section and the conveying section, and the discharging section is made of wear-resistant, high-temperature resistant and fatigue-resistant alloy steel, which is moisture-resistant, wear-resistant, high-temperature resistant, corrosion-resistant, and not easy to crack, effectively extending the service life of the feeding device.
[0035] The sealed air device includes a sealed air duct seat, a sealed air chamber, a sealed air nozzle 11 and an orifice plate; a flange is provided on the feed section, and a sealed air interface 3 is provided on the flange; the sealed air chamber is connected to the sealed air interface 3, and the sealed air interface 3 is connected to the sealed air nozzle 11 and the orifice plate, and the sealed air nozzle 11 and the orifice plate extend into the feed section.
[0036] The material broadcasting air device includes a broadcasting air pipe seat, a broadcasting air chamber, a broadcasting air nozzle 5 and a hole plate. A broadcasting air interface 4 is provided on the feeding section. The broadcasting air chamber is connected to the broadcasting air interface 4. The broadcasting air interface 4 is connected to the broadcasting air nozzle 5 and the hole plate. The broadcasting air nozzle 5 and the hole plate extend into the feeding section. Figure 4 shown.
[0037] The sealing air and the broadcasting air enter the feeding trough through the sealing air nozzle 11 and the orifice plate and the broadcasting air nozzle 5 and the orifice plate respectively.
[0038] The fuel in the feed trough is fed by a feeder 10, and a detachable sealing cover plate 9 with a sealing function is installed on the interface between the two, which is convenient for clearing the blockage in the event of an accidental blockage and ensuring smooth feeding.
[0039] The sealing air is arranged, when the discharge section is under negative pressure, only 1-2% of the sealing air is used; when the discharge section is under positive pressure, the recycled flue gas is used to ensure that the pressure head of the discharge section is greater than the bed pressure in the furnace to prevent the flue gas from flowing back and ensure sealing; the broadcasting air ensures that the broadcasting material falls evenly into the hot material on the air distribution plate, ensuring that the fuel burns quickly and efficiently.
[0040] Working principle: Biomass fuel is fed into the feed trough by the feeder 10, enters the boiler through the feed pipe, and evenly falls into the hot material on the air distribution plate. During this period, when the discharge section is under negative pressure, only a small amount of air is used for sealing air; when the discharge section is under positive pressure, recycled flue gas is used to ensure that the pressure head of the discharge section is greater than the bed pressure in the furnace to prevent flue gas from flowing back. The broadcasting air ensures uniform broadcasting. When high-humidity fuel enters the feed trough, a blocking accident may occur. At this time, the detachable sealing cover plate 9 on the connecting elbow between the feed trough and the feeder 10 can be opened to clear the blockage without stopping the furnace.
[0041] The utility model has the following advantages: 1. Smooth feeding, because of the square or circular cross-sectional structure, and the cross-sectional size remains unchanged or gradually increases, so it is not easy to block the material; 2. There is a means to clear the blockage, because a detachable sealing cover plate 9 is set on the connecting elbow of the feeding trough and the feeder 10, once an accident blockage occurs, it can be cleared by round steel or steel chisel; 3. Effectively prevent the backflow of flue gas, through the sealing wind and the recirculation of flue gas, the pressure of the discharge section is greater than the flue gas pressure in the furnace, and the backflow of the flue gas in the furnace into the feeding device is effectively blocked. 4. To prevent expansion obstruction at the water-cooled wall connection, the upper part of the feeding device is connected to the adjusting and fixing device 1 by a loose nut, and an expansion groove is installed at the welding point between the lower part and the water-cooled wall, so that the feeding device can expand freely upward relative to the water-cooled wall, and the thermal stress can be effectively released along the joint surface of the water-cooled wall, solving the problems of expansion obstruction and easy cracking at the joint of the water-cooled wall; 5. The discharging section is not easy to crack. Since the discharging section is made of wear-resistant, high-temperature and fatigue-resistant alloy steel, it is resistant to moisture, wear, high temperature and corrosion, and is not easy to crack, which effectively extends the service life of the feeding device.
[0042] In short, the feeding device of the biomass circulating fluidized bed boiler is more suitable for various working conditions of biomass fuel feeding, especially for high-humidity, high-corrosion, and high-abrasion biomass fuels (such as furfural slag, sludge, livestock manure, solid waste and other fuels). It has a high tolerance and adaptability, and can effectively prevent problems such as poor feeding, structural expansion obstruction or even cracking, and flue gas backflow, laying the foundation for the stable and continuous operation of the biomass circulating fluidized bed boiler.
[0043] The above description is only a preferred implementation mode of the present utility model. Any technical solution that achieves the purpose of the present utility model by basically the same means belongs to the protection scope of the present utility model.
Claims
1. A feeding device for a biomass circulating fluidized bed boiler, characterized in that: The boiler comprises a water-cooled wall, a feeder (10), a feed trough and a cover (7); the feed trough is connected to the feeder (10) via a connecting elbow, an expansion joint (8) and a detachable sealing cover plate (9) are arranged above the connecting elbow, the feed trough is connected to the upper part of the water-cooled wall via a fixing device (1), and the feed trough is connected to the lower part of the water-cooled wall via the cover (7); The feed trough comprises a feed pipe, a sealing air device, and a material spreading air device. The feed pipe comprises a feed section, a feed section, and a discharge section. The discharge section is provided with a material viewing device (6). The feed section is vertically downward, the feed section is inclined downward, and the inclination angle is 65 degrees. The angle between the discharge section and the feed section is 0 to 15 degrees. A feed interface (2) is provided at the connection between the feed section and the feed section. The material of the discharge section is an alloy material.
2. The biomass circulating fluidized bed boiler feeding device according to claim 1, characterized in that: The cross section of the conveying pipe is circular, polygonal or rectangular, and the area of the cross section of the conveying pipe gradually increases from top to bottom or remains unchanged.
3. The biomass circulating fluidized bed boiler feeding device according to claim 1, characterized in that: The sealed air device comprises a sealed air duct seat, a sealed air chamber, a sealed air nozzle (11) and an orifice plate; a flange is provided on the feed section, and a sealed air interface (3) is provided on the flange; the sealed air chamber is connected to the sealed air interface (3), the sealed air interface (3) is connected to the sealed air nozzle (11) and the orifice plate, and the sealed air nozzle (11) and the orifice plate extend into the feed section.
4. The biomass circulating fluidized bed boiler feeding device according to claim 1, characterized in that: The material broadcasting air device comprises a material broadcasting air pipe seat, a material broadcasting air chamber, a material broadcasting air nozzle (5) and an orifice plate. A material broadcasting air interface (4) is provided on the feeding section. The material broadcasting air chamber is connected to the material broadcasting air interface (4). The material broadcasting air interface (4) is connected to the material broadcasting air nozzle (5) and the orifice plate. The material broadcasting air nozzle (5) and the orifice plate extend into the feeding section.
5. The biomass circulating fluidized bed boiler feeding device according to claim 1, characterized in that: The material viewing device (6) is composed of a pipe cap, heat-resistant glass and a threaded pipe.
6. The biomass circulating fluidized bed boiler feeding device according to claim 1, characterized in that: The fixing device (1) is composed of long and short draw hooks, loose nuts and ear plates.
7. The biomass circulating fluidized bed boiler feeding device according to claim 1, characterized in that: The casing (7) comprises a casing panel, a connection plate and expansion slots. The connection plate is an L-shaped plate or a comb-shaped plate. A certain number of expansion slots are evenly mounted at the connection between the casing (7) and the water-cooled wall.
8. The biomass circulating fluidized bed boiler feeding device according to claim 1, characterized in that: The discharge section can be installed in the negative pressure area or the positive pressure area; when the discharge section is installed in the negative pressure area, the sealing air is 1-2%; when the discharge section is installed in the positive pressure area, the sealing air uses recycled flue gas, so that the pressure head of the discharge section is greater than the bed pressure.