Air distribution plate hood of circulating fluidized bed boiler

Abstract

A wind cap of a wind distribution plate of a circulating fluidized bed boiler belongs to the technical field of wind distribution devices of circulating fluidized bed boilers and is characterized in that wind caps as high as a first exhaust cap are arranged on the periphery and opposite sides on the basis of the height of the first exhaust cap on the front side or the rear side of the boiler; and the length of the inner core pipe connected between the air cap and the air distribution plate is matched with the distance between the air cap and the air distribution plate, so that the air outlets of the air caps are positioned at the same horizontal height. According to the utility model, the height of the air cap is set to be consistent, the problem of non-uniform fluidization is solved, and the air cap head and the air cap base are arranged in a split manner, so that the problem that the air cap is time-consuming and labor-consuming to replace is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of circulating fluidized bed boiler air distribution devices, in particular to an air cap of an air distribution plate of a circulating fluidized bed boiler. Background Art

[0002] The wind caps of the existing circulating fluidized bed boiler air distribution plate are generally located at the lowest position in the middle row of wind caps, and the front and rear wind caps are inclined upward at an angle of about 3° on both sides with the middle row of wind caps as the base point. Figure 1 As shown in the figure, this design is because the slag discharge port is located in the middle of the air distribution plate, and the downward inclination of the middle part is conducive to slag discharge. However, in actual use, it is found that the area with poor fluidization is mainly concentrated in the middle part of the air cap distribution on the air distribution plate, while the front and rear areas are in an over-fluidized state. This is because the middle row of air caps is located at the lowest position, and is squeezed by the air discharge of the high-position air caps on the front and rear sides. The fluidization at this position is the worst. The height difference between the middle and the front and rear air caps is large. As the air caps gradually rise to the sides, the air discharge resistance is significantly reduced. Therefore, the fluidization wind in the front and rear areas is too large, and the material is over-fluidized. The inconsistent height of the air caps leads to deviations in the material thickness on the top of each air cap, inconsistent air discharge resistance, and poor material fluidization. The air caps on the front and rear sides are high, and the upper bed material is relatively thin, while the middle position is low, and the material is relatively thick. Squeezed by the air volume on the front and rear sides, the bed surface air distribution fluidization is poor. In severe cases, the carbon content of the boiler slag is high, and local coking is easy, affecting the safety and stability of operation.

[0003] In addition, the hood outlets are not on the same level, which also leads to increased wear of the hood. The worn hood needs to be replaced in time. Failure to replace it in time will lead to poor fluidization. Traditional hoods are generally one-piece hoods, and the installation method is that the hood is directly connected to the air distribution plate, and the root of the hood is covered with castables. When the hood needs to be replaced after being worn, the castables on the bed surface of the large bed, about 6 tons, must be planed off, the worn hood must be taken out, and then the new hood must be installed and leveled, and the castables must be rebuilt, which takes about 400 man-hours. The replacement of the original one-piece hood is cumbersome, time-consuming and labor-intensive. Utility Model Content

[0004] In view of the above-mentioned shortcomings and deficiencies of the prior art, the utility model provides a hood for an air distribution plate of a circulating fluidized bed boiler, which solves the problem of uneven fluidization by setting the height of the hood to be consistent, and solves the problem of time-consuming and labor-intensive hood replacement by setting the hood head and the hood base separately.

[0005] In order to achieve the above-mentioned purpose, the main technical solutions adopted by the utility model include:

[0006] A circulating fluidized bed boiler air distribution plate hood, based on the height of the first row of hoods on the front or rear side of the boiler, hoods with the same height as the first row of hoods are arranged on the surrounding and opposite sides, the length of the inner core tube connected between the hood and the air distribution plate matches the distance between the hood and the air distribution plate, so that the air outlets of the hood are at the same horizontal height.

[0007] Furthermore, the top of the air distribution plate and the top of the refractory castable filled at the bottom of the wind hood are arranged horizontally.

[0008] Furthermore, the hood includes a hood head and a hood base which are separately arranged. The hood head is threadedly connected to the hood base, and a connecting ring is welded on the outside of the connection between the hood head and the hood base.

[0009] Furthermore, the bottom of the hood head is a downwardly protruding hood head connecting end, the outside of which is formed with threads, and the top of the hood base is a groove-shaped hood base connecting end that matches the protrusion of the bottom of the hood head, and the inner wall of the hood base is formed with threads, and the two threads match each other.

[0010] The beneficial effects of the utility model are:

[0011] 1. The utility model adopts the arrangement of setting the hoods with the same height as the first row of hoods on the front side or the rear side of the boiler as the basis, so as to make the circulating fluidized bed boiler fluidized evenly;

[0012] 2. The utility model provides a split hood and a hood base for the hood, which is convenient for loading and unloading, saves time and effort in the loading and unloading process, and solves the problem of difficulty in replacing the hood after it is worn. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the arrangement of the air distribution plate and hood of the existing circulating fluidized bed boiler;

[0014] Figure 2 It is a schematic diagram of the air distribution plate and hood arrangement of a circulating fluidized bed boiler according to the utility model;

[0015] Figure 3 It is a top view schematic diagram of the air distribution plate and air cap arrangement of a circulating fluidized bed boiler of the utility model;

[0016] Figure 4 This is a schematic diagram of the wind cap structure of the utility model;

[0017] Figure 5 This is a schematic diagram of the connecting ring structure of the utility model.

[0018] Components in the figure: 1 is the air distribution plate, 2 is the hood, 3 is the inner core tube, 4 is the refractory castable, 5 is the front side of the boiler, 6 is the rear side of the boiler, 7 is the hood head, 8 is the hood base, 9 is the hood air outlet, 10 is the connecting ring, and 11 is the welding position. DETAILED DESCRIPTION

[0019] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0020] like Figure 2-3 As shown, the utility model provides a circulating fluidized bed boiler air distribution plate hood. In order to solve the problem of uneven fluidization, the height of the first row of hoods 2 on the front side 5 or the rear side 6 of the boiler is used as the basis, and hoods 2 with the same height as the first row of hoods are arranged around and on the opposite sides. The length of the inner core tube 3 connected between the hood 2 and the air distribution plate 1 matches the distance between the hood 2 and the air distribution plate 1, so that the hood air outlets 9 are all at the same horizontal height. The top of the refractory castable 4 filled at the top of the air distribution plate 1 and the bottom of the hood 2 is arranged horizontally.

[0021] Since the particle size of the coal entering the fluidized bed boiler is less than 13mm, the slag particle size is relatively small after the coal is burned in the furnace. The fine slag particles are light in specific gravity and are not easy to accumulate in the dead zone, affecting the fluidization and slag discharge of the boiler. After the boiler air distribution and leveling transformation, it is more conducive to the uniform circulation of materials, eliminating the fluidization dead zone in the furnace, and facilitating the uniform discharge of fine slag out of the furnace through the slag discharge pipe.

[0022] Furthermore, in order to solve the problem that the hood is time-consuming and labor-intensive to replace, the utility model sets the hood 2 as a split type, such as Figure 4-5 As shown, it includes a separately arranged hood head 7 and a hood base 8, and the hood head 7 is threadedly connected to the hood base 8. The threaded connection is convenient for disassembly and replacement of the hood. In order to firmly connect the hood head 7 and the hood base 8, a connecting ring 10 is welded on the outside of the connection between the hood head 7 and the hood base 8. The welding position 11 is located at the connecting gap between the hood head 7 and the hood base 8 after the hood head 7 and the hood base 8 are assembled, so as to protect the connection between the hood head 7 and the hood base 8 and ensure that the hood is firm and does not fall off. The split-design hood can solve the problem of difficulty in replacing the hood after it is worn.

[0023] Specifically, the bottom of the hood head 7 is a downwardly protruding hood head connecting end, the outside of which is formed with threads, and the top of the hood base 8 is a groove-shaped hood base connecting end that matches the protrusion at the bottom of the hood head, and the inner wall of the hood base is formed with threads, and the two threads match each other.

[0024] Although the embodiments of the present invention have been shown and described above, it is understandable that the above embodiments are illustrative and cannot be construed as limitations on the present invention. Any changes, modifications, substitutions and variations of the above embodiments by a person skilled in the art are all within the scope of the present invention.

Claims

1. A circulating fluidized bed boiler air distribution plate hood, characterized in that: Based on the height of the first row of hoods on the front or rear side of the boiler, hoods with the same height as the first row of hoods are set around and on the opposite sides. The length of the inner core tube connecting the hood and the air distribution plate matches the distance between the hood and the air distribution plate, so that the air outlets of the hoods are at the same horizontal height.

2. The circulating fluidized bed boiler air distribution plate hood according to claim 1, characterized in that: The top of the air distribution plate and the top of the refractory castable filled with the bottom of the wind hood are arranged horizontally.

3. The circulating fluidized bed boiler air distribution plate hood according to claim 1, characterized in that: The hood comprises a hood head and a hood base which are separately arranged. The hood head is threadedly connected with the hood base, and a connecting ring is welded on the outside of the connection between the hood head and the hood base.

4. The circulating fluidized bed boiler air distribution plate hood according to claim 3, characterized in that: The bottom of the hood head is a downwardly protruding hood head connecting end, the outside of which is formed with threads, and the top of the hood base is a groove-shaped hood base connecting end that matches the protrusion of the bottom of the hood head, and the inner wall of the hood base is formed with threads, and the two threads match each other.

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