JPS6032115B2 - Dispersion plate sealing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sealing device for a dispersion plate in a fluidized bed combustion furnace, such as a fluidized bed spoiler, and particularly relates to a sealing device for a dispersion plate in a fluidized bed boiler in which there is a large temperature difference between the front and back surfaces of the dispersion plate. It is something.

Conventionally, as shown in FIG.
A fire-resistant castable 3 is integrally formed on the inside facing the surface of the boiler, and a heat-insulating castable 4 is integrally formed with studs 5 embedded therein on the outside thereof, and the periphery thereof is covered with a main body casing 6 made of a steel plate to form a boiler main body 7. ing.

In such a fluidized bed boiler 1, a normal pressure combustion or a pressurized combustion method is adopted, and air and gas seals are achieved by attaching a flange 8 to the outer wall 6a of the main body casing 6, and attaching a bolt 10 and a nut via a packing 9. This is done by tightening with 11. On the other hand, the fluidized bed 2 and the lower Widpox 12 are separated by a dispersion plate 13, and the combustion air from below passes through the dispersion plate 13 through a group of four ridges 13a arranged in a grid or staggered pattern. fluidized bed 2
It is designed to flow evenly across the entire cross section. On the other hand,
This dispersion plate 13 is mounted on and supported by several support plates 14 fixed to and protruding from the inner wall 6b of the main body casing 6, and the entire circumference of the end portion 13b of the dispersion plate 13 is filled with refractory fibers 15. It is configured to prevent air leakage from the end portion 13b. However, in the above-mentioned conventional technology, since the distribution plate 13 is fixed to the refractory castable, the area around the support plate 14 is damaged due to thermal tension of the support plate 14 and thermal deformation of the distribution plate 13 during boiler operation. There was a drawback that the fireproof castable 3 was damaged and fell off.

In addition, air flows through the damaged part of the castable 3, scattering the refractory fiber 15 filled for sealing the dispersion plate 13,
As a result, the combustion air leaked from the section A in FIG. 1, resulting in insufficient air from the dispersion plate 13, resulting in a disadvantage that stable flow could not be obtained within the fluidized bed 2. The purpose of the present invention is to eliminate the above-mentioned drawbacks of the prior art, to prevent breakage and falling off of refractory caster pulls during normal pressure combustion and pressurized combustion in a fluidized bed boiler, and to distribute the entire amount of necessary air from small diameter holes in the distribution plate. It is an object of the present invention to provide a sealing device for a dispersion plate that allows stable fluidized bed combustion by flowing into a fluidized bed.

In short, in order to allow and absorb the thermal deformation of the dispersion plate caused by the temperature difference between the front and back surfaces, for example, the dispersion plate is disposed freely on both ends of the flange of the main body casing, and the dispersion plate and the main body peripheral wall are connected to each other. are connected and sealed with a flexible expansion bellows to prevent air leakage.

The present invention will be described below with reference to a first embodiment. In FIG. 2, 21 is a fluidized bed boiler; 22 is a fluidized bed;
24 is a fireproof castable, 24 is a heat insulating castable, 25 is a stud, 26 is a main body casing made of a steel plate, 27 is a boiler main body, and 32 is a weed box, which are similar to the diamond pupil of the prior art described above. 28 is a flange;
These are connected to the bolt 30 and nut 3 through the packing 29.
1 is also tightened, but the lower flange 28a is extended inward, and the dispersion plate 33 is attached to the extended portion 28b.
The end portion 33b is freely layered at both ends.

Therefore, the distribution plate 33 is not fixed to the boiler main body 27, but a reinforcing plate 34 is fixed to the back surface of the dispersion plate 33, and an M-shaped expansion bellows 36 is installed between the reinforcing plate and the inner wall 26b of the main body casing 26. The expansion bellows and the upper and lower ends 33b of the dispersion plate 33 are filled with refractory fibers 35 so that the expansion bellows 36 can sufficiently absorb thermal deformation of the dispersion plate 33. Therefore, in this embodiment, when combustion air is sent from below the whid box as shown by the arrow 37, it flows into the fluidized bed 22 as shown by the arrow 38 through the small diameter hole 33a of the distribution plate 33. Combustion takes place in

The front surface of the dispersion plate 33 is heated, and a temperature difference occurs between the dispersion plate 33 and the back surface, causing the dispersion plate 33 to deform.However, the reinforcing plate 34 fixed thereon only expands and contracts the expansion bellows 36, and the boiling body 27 Since no unreasonable force is exerted on the refractory castable 23, damage or falling off of the refractory castable 23 can be prevented, and combustion air is evenly supplied into the fluidized bed 22 from the entire surface of the dispersion plate 33. Next, the present invention will be explained with reference to the second embodiment. As shown in FIG. 3, this embodiment is suitable for a large fluidized bed boiler, whereas the first embodiment is suitable for a relatively small fluidized bed boiler. A support beam 60 supports the inner end 53c of the dispersion plate 53 that distributes grain at the bottom of the fluidized bed 42.
The outer end portion 53b is freely supported by the fireproof castable 43, and the outer end portion 53b and the main body casing 46
A U-shaped expansion bellow is joined to the top and bottom of the expansion bellows, and refractory fibers 55 are filled at both upper and lower ends of the expansion bellows.

On the other hand, a stopper 59 is attached to the inner end portion 53c to prevent the dispersion plate 53 from being thermally deformed and moved during operation, and to prevent air leakage from this portion.
A reinforcing plate 54 is fixed to the back surface of the frame 3, and an M-shaped expansion tongue 56' is attached to the reinforcing plate 54 and the support beam 60.
are bonded to each other so that thermal deformation of the dispersion plate 53 can be sufficiently absorbed. The rest is the same as the first embodiment. Therefore, in this embodiment, even if the dispersion plate 53 is thermally deformed, the stopper 59 prevents the dispersion plate 53 from moving beyond a certain limit, and the outer end portion 53b deforms the expansion bellows 56 and moves outward, thereby preventing thermal deformation. Combustion air is sufficiently absorbed to prevent the fireproof castable 43 from breaking or falling off, and is supplied from below the whid box 52 as shown by the arrow 57.
It passes through the small diameter hole 53a of the dispersion plate 53 as shown by the arrow 58 and flows evenly over the entire surface of the fluidized bed 42.

According to the present invention as described above, the dispersion plate is not fixedly attached to the castable, but is supported by the flange or support beam, and therefore the castable is damaged due to thermal tension and thermal deformation of the dispersion plate. The effect of this is that there is no fear of causing damage.

Next, connect the back surface of the dispersion plate and the inner surface of the main body casing to an M or U shape.
Since it is bonded and sealed to the expansion bellows of the mold, it can sufficiently tolerate and absorb the vertical and horizontal thermal deformation of the distribution plate that inevitably occurs in fluidized bed boilers, and prevents combustion air from flowing from the edge of the distribution plate. This has the effect that leakage can be completely prevented and, as a result, stable flow can be obtained within the layer.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing the dispersion plate and its mounting state in a conventional fluidized bed poller, and FIGS.
FIG. 7 is a vertical cross-sectional view showing a dispersion plate and its attached state in an example and a second example, respectively. 21... Fluidized bed poller, 33, 53... Dispersion plate, 36,
56, 56'...Expansion bellows Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1. A sealing device for a dispersion plate, characterized in that the dispersion plate and the main body of a fluidized bed combustion furnace are joined by an expansion bellows to maintain airtightness while allowing deformation of the dispersion plate. . 2. A dispersion plate according to claim 1, characterized in that a dispersion plate formed by joining one or more dispersion plates with an expansion bellows is joined to a fluidized bed combustion furnace body via an expansion bellows. sealing device.