Multifunctional adjustable self-protection direct-current pulverized coal burner
By designing a multifunctional adjustable self-protection DC pulverized coal burner, the problem of overheating and burnout of pulverized coal burners in the standby state is solved, achieving flexible cooling protection and coal type adaptability, and improving the burner's protection capability and operational adjustment flexibility.
Patent Information
- Application Number
- CN202520017201.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-03
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2035-01-03
AI Technical Summary
Existing pulverized coal burners are prone to overheating and burning when shut down or in standby mode. In particular, single-mill stratified burners suffer from flue gas backflow and pulverized coal accumulation, resulting in insufficient cooling.
A multifunctional adjustable self-protection DC pulverized coal burner was designed. Through the combination of a primary air duct and a secondary air duct, the air duct and pulverized coal nozzle can be flexibly adjusted to prevent high-temperature flue gas radiation and flue gas backflow, and enhance cooling protection.
It effectively prevents pulverized coal burners from overheating, enhances adaptability to different coal types and operational flexibility, and improves self-protection capabilities and cooling effects during shutdown and standby.
Smart Images
Figure CN223726336U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of coal (oil gas) power generation, especially to multifunctional adjustable self -protection direct -current coal powder burner. BACKGROUND
[0002] At present, thermal power generation is still the main source of power supply in China, and coal-fired power plants account for the vast majority of thermal power installed capacity. Thermal power units carry out deep peak regulation to accommodate new energy power generation, which has become the normal operation of many thermal power plants. Whether full load operation or deep peak regulation operation, part of the coal powder burner in the coal-fired boiler is often in standby state, and the low temperature primary air flow in these standby coal powder burners provides cooling for them. Due to the radiation of high temperature flue gas in the boiler, the coal powder burner is prone to overheating, especially the overheating and burning of coal powder nozzle. In some coal powder burners with single mill layer combustion, due to the height difference between the two layers of burners, when standby, it is easy to produce smoke backflow to the inside of the burner, which superimposes the factors of coal powder pipe or burner internal powder accumulation, causing the internal high temperature of the burner and even fire and burning of the burner.
[0003] In order to avoid the above problems, the boiler operator often increases the supply of perimeter air to the standby coal powder burner to cool the burner. However, due to the small proportion of perimeter air volume and the fact that it is only outside the coal powder nozzle, the cooling effect is not enough, resulting in the problem of burning of the standby layer coal powder burner not being effectively solved. UTILITY MODEL CONTENTS
[0004] The utility model discloses a multifunctional adjustable self -protection direct -current coal powder burner, has adjustment function, realizes good cooling protection effect, flexible adjustment coal powder spout position and the purpose of enhancing coal kind adaptability.
[0005] In order to achieve the above purpose, the technical scheme of the utility model provides a multifunctional adjustable self -protection direct -current coal powder burner, which comprises a wind box, a primary air cylinder and a secondary air cylinder are arranged in the wind box, the outlet end of the primary air cylinder penetrates the inlet end of the secondary air cylinder, the outlet end of the secondary air cylinder is sleeved with a coal powder nozzle, the inlet end of the primary air cylinder and the inlet end of the coal powder nozzle respectively penetrate two opposite sides of the wind box, and the secondary air cylinder and the coal powder nozzle can move axially along the primary air cylinder to adapt to different operating conditions.
[0006] Preferably, when in the working position, the gap H1 between the mutual nesting parts of the primary air cylinder and the secondary air cylinder is equal everywhere.
[0007] Preferably, when in the working position, the primary air duct and the secondary air duct are nested with each other by a length L0 greater than or equal to 50 mm, and the gap H1 is less than or equal to 5 mm; when in the protection position, the minimum gap H2 between the primary air duct and the secondary air duct is greater than or equal to 20 mm.
[0008] Preferably, the primary air duct has a circular cross section at the inlet end, a square-circular segment at the middle position, and a square cross section at the outlet end with a gradually expanding structure; the secondary air duct has a gradually expanding structure at the inlet end and a Venturi tube type structure at the outlet end.
[0009] Preferably, the bellow is provided with a driving device for moving the secondary air duct on the side where the inlet end of the primary air duct is located, and the driving device comprises a positioning sleeve provided on the side of the bellow and an adjusting pull rod penetrating through the positioning sleeve and connected to the secondary air duct.
[0010] Preferably, the positioning sleeve and the adjusting pull rod can be vertically penetrated by a positioning pin.
[0011] Preferably, the adjusting pull rod is connected to a straight stroke pneumatic actuator outside the bellow.
[0012] Preferably, the inlet end of the primary air duct is fixedly connected to the bellow by a flange.
[0013] Preferably, the primary air duct and the secondary air duct are both provided with support wheel frames on both sides, the inside bottom of the bellow is provided with guide rails matched with the support wheel frames on both sides of the secondary air duct, and the top of the primary air duct is fixedly connected to a limiting wheel frame.
[0014] Preferably, the primary air duct is provided with a positioning stopper on the outer surface, and the end of the guide rail close to the coal powder injection port is provided with a protruding positioning block, and the protruding positioning block and the positioning stopper are used to constrain the maximum position of the forward and backward movement of the secondary air duct.
[0015] The advantage of the utility model is that by adjusting, the position of the secondary air duct and the coal powder injection port assembly relative to the side of the hearth can be changed. When the coal powder burner is normally put into operation, it is in the working position; when the coal powder burner is stopped for standby, it is in the protection position. In the protection position, the coal powder injection port and the secondary air duct move backward together, away from the high-temperature flue gas of the hearth, reducing the radiation heating, and part of the secondary air flows through the inside of the secondary air duct and the coal powder injection port, preventing the backflow of high-temperature flue gas and strengthening the cooling protection effect of the secondary air flow. The double effects of moving backward away from the high-temperature flue gas of the hearth and the enhanced cooling effect of the secondary air greatly improve the anti-overheating self-protection ability of the coal powder burner when it is stopped for standby. The forward and backward movement of the secondary air duct and the coal powder injection port can also change the position of the coal powder flow into the hearth, and then change the position of the coal powder ignition point in the hearth, achieving the purpose of adjusting the coal powder ignition and stable combustion.
[0016] The multifunctional adjustable self-protection direct-current coal powder burner of the utility model has realized the anti-overheating protection of the coal powder burner during standby, enhanced the adaptability of the coal powder burner to different coal types and the flexibility of operation adjustment, and expanded the functions of the coal powder burner. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 It is a front view schematic diagram of embodiment 1 of the utility model multifunctional adjustable self-protection direct-current coal powder burner.
[0018] Figure 2 It is a plane view schematic diagram of embodiment 1 of the utility model multifunctional adjustable self-protection direct-current coal powder burner.
[0019] Figure 3 It is Figure 1 It is a sectional view when working position and protection position of A in the middle.
[0020] Figure 4 It is a front view schematic diagram of embodiment 2 of the utility model multifunctional adjustable self-protection direct-current coal powder burner.
[0021] The drawings show that: 1, primary air cylinder; 2, support wheel frame; 3, air bellow; 4, secondary air cylinder; 5, guide rail; 6, coal powder injection port; 7, adjusting pull rod; 8, positioning sleeve; 9, positioning pin; 10, positioning block; 11, limiting wheel frame; 12, fixed pin; 13, straight stroke pneumatic actuator. DETAILED DESCRIPTION
[0022] The technical solutions in the embodiments of the utility model will be described clearly and completely below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.
[0023] Embodiment 1:
[0024] The utility model embodiment discloses a kind of segmented adjustable, strong multifunctional direct-current coal powder burner of protection, and multifunctional adjustable self-protection direct-current coal powder burner is by primary air cylinder 1, support wheel frame 2, air bellow 3, secondary air cylinder 4, guide rail 5, coal powder injection port 6, adjusting pull rod 7, positioning sleeve 8, positioning pin 9, positioning block 10, limiting wheel frame 11, fixed pin 12.
[0025] The first air cylinder 1 is fixedly connected with the air box 3 through a flange at an inlet end, and is fixedly connected with a set of support wheel frames 2 at two sides. The inlet end of the first air cylinder 1 is circular in cross section and is connected with a pulverized coal pipeline; a middle position is a square-circular section, and an outlet end is square in cross section and is gradually expanded. The second air cylinder 4 is fixedly connected with the pulverized coal nozzle 6 through a fixing pin 12, and is fixedly connected with two sets of support wheel frames 2 at two sides and with a limiting wheel frame 11 at an upper portion. The inlet end of the second air cylinder 4 is gradually expanded and is sleeved on the outlet end of the first air cylinder 1. The outlet end of the second air cylinder 4 is in a Venturi tube type structure. The front portion of the guide rail 5 is provided with a protruding positioning block fixed in the air box 3 and matched with the support wheel frames 2 to move and guide and forwardly limit the second air cylinder 4.
[0026] One end of the adjusting pull rod 7 is fixedly connected with the second air cylinder 4, and the other end is passed through a positioning sleeve 8 fixedly connected with the air box 3. The adjusting pull rod 7 is provided with a plurality of through holes at intervals at a position close to the air box 3. The positioning sleeve 8 is provided with a positioning through hole with a size same as that of the through hole of the adjusting pull rod 7. A positioning pin 9 can pass through the through hole to limit and connect the positioning sleeve 8 and the adjusting pull rod 7. Positioning blocks 10 are fixedly connected at two sides of the first air cylinder 1 and are away from the inlet end of the second air cylinder 4 by a distance L.
[0027] In the utility model, under the pushing and pulling action of the adjusting pull rod 7, the second air cylinder 4 is moved forward and backward along the axial direction through the rolling of the support wheel frames 2 along the guide rail 5 and the rolling of the limiting wheel frame 11. When the adjusting pull rod 7 is pushed forward, the combined part of the second air cylinder 4 and the pulverized coal nozzle 6 is moved forward and the distance from the furnace is reduced. When the adjusting pull rod 7 is pulled backward, the combined part of the second air cylinder 4 and the pulverized coal nozzle 6 is moved backward and the distance from the furnace is increased. The protruding block at the front portion of the guide rail 5 and the positioning blocks 10 at two sides of the first air cylinder 1 constitute the constraint of the maximum position of the forward and backward movement of the second air cylinder 4. When the second air cylinder 4 is adjusted to the required position, the positioning pin 9 is inserted into the through holes of the positioning sleeve 8 and the adjusting pull rod 7 to realize the fixing of the second air cylinder 4. The adjusting pull rod 7 is provided with a plurality of through holes and can correspond to different positions of the second air cylinder 4.
[0028] The relative positions of the first air cylinder 1 and the second air cylinder 4 are shown in Figure 3 When the pulverized coal burner is normally put into operation, the first air cylinder 1 and the second air cylinder 4 are in the working position, the distance between the two air cylinders is H1, and the covering distance is L0; when the pulverized coal burner is stopped for standby, the second air cylinder 4 is moved backward, and the gap distance between the two air cylinders is H2. Preferably, L0≥50mm, H1≤5mm, and H2≥20mm.
[0029] In the working position, the small H1 gap and the secondary air in the wind box 3 play a sealing role, avoiding too much secondary air from mixing into the primary air in advance and preventing the primary air and the pulverized coal from leaking out of the air duct. In the protection position, the secondary air duct 4 and the pulverized coal injection port 6 move backward together, away from the high-temperature flue gas in the furnace, reducing the radiation heating, and the large gap distance H2 allows part of the secondary air in the wind box 3 to flow into the secondary air duct 4 and the pulverized coal injection port 6 and then into the furnace, preventing the high-temperature flue gas from flowing back into the air duct and enhancing the cooling protection effect of the secondary air from the inside. The dual effects of moving backward away from the high-temperature flue gas in the furnace and enhancing the cooling effect of the secondary air greatly improve the anti-overheating self-protection capability of the pulverized coal burner during standby.
[0030] The forward and backward movement of the secondary air duct 4 can correspondingly realize the forward and backward movement of the pulverized coal injection port 6, thereby changing the position of the primary air and the pulverized coal flow into the furnace, and then changing the position of the coal ignition point in the furnace, achieving the purpose of adjusting the coal ignition and stable combustion. When burning coal with low volatile matter, it is appropriate to reduce the distance between the secondary air duct 4 and the furnace to promote the contact and heat exchange between the pulverized coal flow and the high-temperature flue gas. When burning coal prone to slagging, it is appropriate to increase the distance between the secondary air duct 4 and the furnace to delay the coal ignition and reduce the radiation heat of the high-temperature flue gas on the pulverized coal injection port 6.
[0031] The present utility model adjusts the forward and backward position of the combination of the secondary air duct 4 and the pulverized coal injection port 6, which not only realizes the anti-overheating protection of the pulverized coal burner during standby, but also enhances the adaptability of the pulverized coal burner to different coal and the flexibility of operation adjustment, so that the function of the pulverized coal burner is expanded.
[0032] Embodiment 2:
[0033] As shown in Figure 4 , it is a plane schematic view of another multifunctional adjustable self-protecting direct-flow pulverized coal burner. The difference between this embodiment and embodiment 1 is that there is no positioning pin 9, and the forward and backward push-pull movement of the adjusting pull rod 7 is driven by the straight stroke pneumatic actuator 13 fixed on the wind box 3, so that the adjustment of the secondary air duct 4 can be included in the power plant DCS system to realize automatic control and facilitate remote operation by the boiler operator. The other structures are the same as those in embodiment 1.
[0034] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or make equivalent replacements to some technical features, as long as they are within the spirit and principles of the present utility model. Any modification, equivalent replacement, improvement, etc. made within the scope of the present utility model should be included in the protection scope of the present utility model.
Claims
1. Multifunctional adjustable self-protected DC coal dust burner, characterized in that, The utility model relates to a wind box (3) is provided with primary wind cylinder (1) and secondary wind cylinder (4) in it, the outlet end of primary wind cylinder (1) is provided with the inlet end of secondary wind cylinder (4), the outlet end of secondary wind cylinder (4) is provided with coal powder spout (6), the inlet end of primary wind cylinder (1) and the inlet end of coal powder spout (6) are provided with the two opposite sides of wind box (3) respectively, and secondary wind cylinder (4) and coal powder spout (6) can move along the axial direction of primary wind cylinder (1) to adapt to different operating conditions.
2. The multifunctional adjustable self-protected DC coal dust burner according to claim 1, characterized in that, When in the working position, the gap H1 between the nested parts of the primary wind cylinder (1) and the secondary wind cylinder (4) is equal everywhere.
3. The multifunctional adjustable self-protected DC coal dust burner according to claim 2, characterized in that, When in the working position, the length L0 of the nested parts of the primary wind cylinder (1) and the secondary wind cylinder (4) is greater than or equal to 50 mm, and the gap H1 is less than or equal to 5 mm; when in the protection position, the minimum gap H2 between the nested parts of the primary wind cylinder (1) and the secondary wind cylinder (4) is greater than or equal to 20 mm.
4. The multifunctional adjustable self-protected DC coal dust burner according to claim 3, characterized in that, The inlet end of the primary wind cylinder (1) is circular in cross section, the middle part is a square-circular segment, and the outlet end is square in cross section and gradually widened; the inlet end of the secondary wind cylinder (4) is gradually widened, and the outlet end is in the form of a Venturi tube.
5. The multifunctional adjustable self protected DC coal powder burner according to claim 1, characterized in that, The wind box (3) is provided with a driving device for moving the secondary wind cylinder (4) on the side where the inlet end of the primary wind cylinder (1) is located, and the driving device comprises a positioning sleeve (8) provided on the side of the wind box (3) and an adjusting pull rod (7) provided through the positioning sleeve (8) and connected to the secondary wind cylinder (4).
6. The multifunctional adjustable self-protected DC coal dust burner according to claim 5, characterized in that, The positioning sleeve (8) and the adjusting pull rod (7) can be vertically provided with a positioning pin (9).
7. The multifunctional adjustable self-protected DC coal dust burner according to claim 5, characterized in that, The adjusting pull rod (7) is connected to a straight-stroke pneumatic actuator (13) outside the wind box (3).
8. The multifunctional adjustable self protected DC coal powder burner according to claim 1, characterized in that, The inlet end of the primary wind cylinder (1) is fixedly connected to the wind box (3) by a flange.
9. The multifunctional adjustable self protected DC coal powder burner according to claim 1, characterized in that, Both the primary wind cylinder (1) and the secondary wind cylinder (4) are provided with support wheel frames (2) on both sides, the inside bottom of the wind box (3) is provided with guide rails (5) matched with the support wheel frames (2) on both sides of the secondary wind cylinder (4), and the top of the primary wind cylinder (1) is fixedly connected to a limiting wheel frame (11).
10. The multifunctional adjustable self-protected DC coal dust burner according to claim 9, characterized in that, The primary wind cylinder (1) is provided with a positioning stop block (10) on the outer surface, the end of the guide rail (5) close to the coal powder spout (6) is provided with a protruding positioning block, and the protruding positioning block and the positioning stop block (10) are used to constrain the maximum position of the forward and backward movement of the secondary wind cylinder (4).