Anti-expansion slag falling pipe structure of circulating fluidized bed boiler
By using structures such as annular reinforcement hoops, reinforcement ring plates and expansion joints in the slag drop pipe of the circulating fluidized bed boiler, the welding problem caused by the expansion of the slag drop pipe in a high-temperature environment is solved, and the stable operation and sealing of the boiler are achieved. .
Patent Information
- Application Number
- CN202420129741.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-18
- Publication Date
- 2025-01-07
- Estimated Expiration
- 2034-01-18
AI Technical Summary
The slag pipe of the circulating fluidized bed boiler is prone to expand in a high-temperature environment, resulting in deformation of the pipe mouth and cracking at the weld, affecting normal operation.
The structures of ring-shaped reinforcement hoops, reinforcement ring plates, expansion joints and high-temperature resistant aluminum silicate fiber felt are adopted to increase the strength of the pipe port and the welding area, and absorb the expansion amount through the expansion joints of the multi-layer metal corrugated pipe to ensure sealing and welding stability.
It effectively avoids cracking at the welding of the slag pipe and the air cloth plate, ensures the normal operation and sealing of the boiler, and extends the service life of the equipment.
Smart Images
Figure CN222316941U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a circulating fluidized bed boiler, in particular to a slag falling pipe structure of a circulating fluidized bed boiler with an anti-expansion property. Background Art
[0002] The circulating fluidized bed boiler combustion technology is a highly efficient, low-pollution clean coal-burning technology. Its main process is: the fuel burned in the furnace is carried to the upper part of the furnace by the flue gas, and the material is separated from the flue gas by a high-efficiency separator arranged at the furnace outlet, and then returned to the furnace through a non-mechanical return valve to achieve multiple cycles of combustion; the ash after the combustion of the circulating fluidized bed boiler fuel is discharged from the bottom of the furnace in the form of bottom ash and from the tail of the boiler in the form of fly ash; the bottom ash is discharged from the slag dropping pipe on the water-cooled air distribution plate at the bottom of the furnace to the outside of the furnace, and the continuous slag discharge of the bottom ash is achieved through the cooling and conveying device; the slag dropping pipe It is arranged in the water-cooled air chamber at the bottom of the furnace; there is a certain amount of bed material at the bottom of the furnace, and the bed material has a relatively high temperature under the operating conditions of the boiler. Since there is no cooling measure for the slag dropping pipe above the air distribution plate, this part of the slag dropping pipe is in a high temperature environment for a long time, which can easily lead to the softening of the pipe mouth, the shrinkage of the pipe diameter, and the change of the pipe mouth from a round shape to an ellipse or a plum blossom shape, which directly leads to the difficulty of slag discharge from the slag dropping pipe; in addition, when the high-temperature slag is discharged through the slag dropping pipe, the slag dropping pipe will expand due to the heat, and the expansion displacement of the slag dropping pipe often causes cracks at the welding point between the slag dropping pipe and the air distribution plate, resulting in frequent failures of the slag dropping pipe, affecting the normal operation of the circulating fluidized bed boiler. Summary of the invention
[0003] The utility model provides an expansion-resistant slag falling pipe structure of a circulating fluidized bed boiler, which solves the technical problem of how to avoid cracking at the welding position between the slag falling pipe and an air distribution plate due to expansion displacement of the slag falling pipe.
[0004] The utility model solves the above technical problems through the following technical solutions:
[0005] A slag pipe structure of an anti-expansion circulating fluidized bed boiler comprises a water-cooled air chamber at the lower part of a furnace, an air distribution plate is arranged in the water-cooled air chamber, a wind cap, a water-cooled pipe and a slag pipe upper through hole are arranged on the air distribution plate respectively, a slag pipe lower through hole is arranged on the lower bottom surface of the water-cooled air chamber, a slag pipe is arranged between the slag pipe lower through hole and the slag pipe upper through hole, an annular reinforcement hoop is fixedly arranged on the outer side wall of the slag pipe in the slag pipe upper through hole, the annular reinforcement hoop and the slag pipe upper through hole are welded together by an annular weld, and a slag pipe upper through hole is arranged on the upper side of the slag pipe. On the outer side wall of the upper port of the slag dropping pipe, reinforcing ring plates are arranged at intervals; on the slag dropping pipe below the lower through hole of the slag dropping pipe, an annular sealing box is movably sleeved, and the upper end of the annular sealing box is welded and connected to the bottom end face of the water-cooled air chamber; on the slag dropping pipe below the annular sealing box, an expansion joint and a ring plate connecting the bottom end of the expansion joint are sleeved in sequence, the upper end of the expansion joint is welded and connected to the bottom end face of the annular sealing box, the lower end of the expansion joint is welded and connected to the top end face of the ring plate connecting the bottom end of the expansion joint, and the ring plate connecting the bottom end of the expansion joint is welded and connected to the outer side face of the slag dropping pipe.
[0006] The distance between the through hole on the slag dropping pipe and the adjacent water-cooling pipe is 30 mm; an air distribution plate fin is arranged on the air distribution plate outside the through hole on the slag dropping pipe, and the annular reinforcement hoop is welded to the air distribution plate fin, and the annular sealing box and the expansion joint are filled with high-temperature resistant aluminum silicate fiber felt.
[0007] The upper end of the slag dropping pipe of the utility model is reinforced by two layers of reinforcing ring plates, so as to increase the strength of the pipe mouth and solve the problem of deformation of the pipe mouth due to heat; the upper part of the slag dropping pipe is fixed to the air distribution plate by an annular reinforcing hoop, so as to increase the contact area between the slag dropping pipe and the air distribution plate, which plays a certain role in solving the problem of cracking at the welding place between the slag dropping pipe and the air distribution plate; a multi-layer metal bellows expansion joint with good flexibility and strong deformation compensation ability is adopted on the outer side of the bottom of the water-cooled air chamber to absorb the expansion of the slag dropping pipe and realize the free expansion of the slag dropping pipe, which not only ensures the sealing between the slag dropping pipe and the water-cooled air chamber, but also solves the problem of cracking at the welding place between the slag dropping pipe and the air distribution plate. The expansion joint is made of stainless steel to increase its fatigue life. BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Figure 1 It is a structural schematic diagram of the utility model;
[0009] Figure 2 It is a schematic diagram of the structure of the slag dropping pipe 6 of the utility model;
[0010] Figure 3 It is a schematic diagram of the connection structure between the slag dropping pipe 6 and the expansion joint of the utility model;
[0011] Figure 4It is a position relationship diagram between the slag dropping pipe 6 and the water cooling pipe 12 of the utility model. Implementation
[0012] The utility model is described in detail below with reference to the accompanying drawings:
[0013] A slag dropping pipe structure of an anti-expansion circulating fluidized bed boiler comprises a water-cooled air chamber 1 at the lower part of a furnace, an air distribution plate 2 is arranged in the water-cooled air chamber 1, a wind cap 3, a water-cooled pipe 12 and a slag dropping pipe upper through hole 5 are respectively arranged on the air distribution plate 2, the water-cooled pipe 12 is arranged on the lower bottom surface of the air distribution plate 2, a slag dropping pipe lower through hole 4 is arranged on the lower bottom surface of the water-cooled air chamber 1, a slag dropping pipe 6 is arranged between the slag dropping pipe lower through hole 4 and the slag dropping pipe upper through hole 5, the bottom slag in the furnace is discharged out of the furnace through the slag dropping pipe 6, an annular reinforcement hoop 10 is fixedly arranged on the outer side wall of the slag dropping pipe 6 in the slag dropping pipe upper through hole 5, the annular reinforcement hoop 10 is welded to the outer side wall of the slag dropping pipe 6, the annular reinforcement hoop 10 and the slag dropping pipe upper through hole 5 are welded together by annular welds, thereby increasing the connection area between the slag dropping pipe 6 and the air distribution plate 2, On the outer side wall of the upper port of the slag dropping pipe 6 above the through hole 5 on the slag dropping pipe, reinforcing ring plates 11 are arranged at intervals; on the slag dropping pipe 6 below the through hole 4 below the slag dropping pipe, an annular sealing box 7 is movably sleeved, and the upper end of the annular sealing box 7 is welded and connected to the bottom end face of the water-cooled air chamber 1, and on the slag dropping pipe 6 below the annular sealing box 7, an expansion joint 8 and an annular plate 9 connecting the bottom end of the expansion joint are sleeved in sequence, the upper end of the expansion joint 8 is welded and connected to the bottom end face of the annular sealing box 7, the lower end of the expansion joint 8 is welded and connected to the top end face of the annular plate 9 connecting the bottom end of the expansion joint, and the annular plate 9 connecting the bottom end of the expansion joint is welded and connected to the outer side face of the slag dropping pipe 6; when the slag dropping pipe 6 expands due to heat, the annular plate 9 connecting the bottom end of the expansion joint is driven to expand and move together, and the expansion amount is absorbed by the expansion joint 8, thereby avoiding the displacement between the slag dropping pipe 6 and the air distribution plate 2.
[0014] The distance between the through hole 5 on the slag dropping pipe and the adjacent water-cooled pipe 12 is 30 mm, which avoids the expansion force of the slag dropping pipe 6 being transmitted to the water-cooled pipe 12, causing leakage of the water-cooled pipe 12; an air distribution plate fin 13 is arranged on the air distribution plate 2 outside the through hole 5 on the slag dropping pipe, and the annular reinforcement hoop 10 is welded to the air distribution plate fin 13. The annular sealing box 7 and the expansion joint 8 are filled with high-temperature resistant aluminum silicate fiber felt 14 to prevent the annular sealing box 7 and the expansion joint 8 from over-temperature damage.
Claims
1. A slag dropping pipe structure of an anti-expansion circulating fluidized bed boiler, comprising a water-cooled air chamber (1) at the lower part of a furnace, an air distribution plate (2) being arranged in the water-cooled air chamber (1), an air cap (3), a water-cooled pipe (12) and a slag dropping pipe upper through hole (5) being arranged on the air distribution plate (2), and a slag dropping pipe lower through hole (4) being arranged on the lower bottom surface of the water-cooled air chamber (1), characterized in that: A slag dropping pipe (6) is arranged between the lower through hole (4) of the slag dropping pipe and the upper through hole (5) of the slag dropping pipe. An annular reinforcing hoop (10) is fixedly arranged on the outer wall of the slag dropping pipe (6) in the upper through hole (5) of the slag dropping pipe. The annular reinforcing hoop (10) and the upper through hole (5) of the slag dropping pipe are welded together by an annular weld. Reinforcing ring plates (11) are arranged at intervals on the outer wall of the upper end of the slag dropping pipe (6) above the upper through hole (5) of the slag dropping pipe. A movable sleeve is arranged on the slag dropping pipe (6) below the lower through hole (4) of the slag dropping pipe. An annular sealing box (7) is provided, the upper end of the annular sealing box (7) is welded to the bottom end surface of the water-cooling air chamber (1), an expansion joint (8) and a bottom end connecting ring plate (9) of the expansion joint are sleeved in sequence on the slag dropping pipe (6) below the annular sealing box (7), the upper end of the expansion joint (8) is welded to the bottom end surface of the annular sealing box (7), the lower end of the expansion joint (8) is welded to the top end surface of the bottom end connecting ring plate (9), and the bottom end connecting ring plate (9) of the expansion joint is welded to the outer side surface of the slag dropping pipe (6).
2. The anti-expansion slag pipe structure of a circulating fluidized bed boiler according to claim 1, characterized in that: The spacing between the through hole (5) on the slag dropping pipe and the adjacent water-cooling pipe (12) is 30 mm; an air distribution plate fin (13) is provided on the air distribution plate (2) outside the through hole (5) on the slag dropping pipe, and the annular reinforcement hoop (10) is welded to the air distribution plate fin (13); and the annular sealing box (7) and the expansion joint (8) are filled with high-temperature resistant aluminum silicate fiber felt (14).