JPH04217708A - Fluidized-bed incinerator - Google Patents

Abstract

PURPOSE:To certainly discharge incombusibles even when such fuel as coal containing rough granular ash, refuse containing metallic pieces, gravel and earth lumps, and others is burned. CONSTITUTION:Air distribution plates 19 are mounted above a central air chamber divided by partition plates 14, and inclined from side walls 10c and 10d of a furnace main body, which face each other and are nearly perpendicular to the partition plates 14, toward the center of the furnace main body. An incombustible discharge port 40 is provided between the ends of slopes of the central air distribution plates 19.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention burns fuel such as coal with coarse ash and waste containing incombustible materials such as metal pieces and rocks.
This invention relates to a fluidized bed combustion furnace that reliably discharges incombustible materials.

0002

[Prior Art] A fluidized combustion furnace blows out air from an air distribution plate to displace a fluidized medium such as sand (for example, silica sand) or limestone.
Burns fuel such as coal and waste in a fluidized state. However, if the fuel contains ash, especially incombustibles such as metal pieces and clay, the incombustibles settle and accumulate on the air distribution plate, making it impossible to maintain good combustion conditions. For this reason, various proposals have been made regarding the shape and discharge mechanism of the air distribution plate for discharging noncombustibles to the outside of the furnace.

[0003] As a conventional technique, for example, Japanese Patent Application Laid-Open No. 63
There is a technique disclosed in Publication No. -271016. FIG. 6 is a perspective view showing the inside of a fluidized bed combustion furnace described in JP-A-63-271016. In Figure 6,
10 is a furnace main body, 12 is a wind box main body, 12a to 12c are wind boxes partitioned by a partition wall 14, 16 is an incombustible material discharge port, 1
8 from both opposing walls of the furnace body toward the center,
The air distribution plate is formed to be inclined downward, 20 is an opening in the shape of a long hole, and 22 is a waste input port.

In the fluidized bed combustion furnace described in this publication,
The ash, metal pieces, dirt, etc. in the settled fuel are moved onto the air distribution plate 18, which is formed by slanting downward, toward the center of the furnace, and the non-combustible material waste having an elongated opening 20 is removed. It is discharged through outlet 16.

[0005]

[Problems to be Solved by the Invention] There are various techniques for discharging incombustibles from the elongated hole-shaped discharge port 16 as shown in FIG. 6, but all of them have problems.

FIG. 7 is a diagram showing an example of this, where 16 is a long hole-shaped incombustible material discharge port, 24 is a cylindrical rotating gear,
A sectional view thereof is shown in FIG. Non-combustible materials are discharged from the system by the plurality of teeth 26. However, since this method handles a fluidized medium at a high temperature of 600 to 900° C., it requires a large amount of equipment cost for a heat-resistant structure, but it is still quite difficult to create a highly reliable structure. In addition, non-combustible materials become entangled with the teeth 26, making it difficult to discharge them stably.

FIG. 9 also shows a long hole-shaped incombustible material discharge port 1.
A cone portion 28 constricted in the shape of an inverted truncated cone is connected to the bottom of the cone 6, and a rotary valve 30 is installed at the bottom of the cone portion 28 as a non-combustible material discharger.
has been established. A disadvantage of this structure is that the angle θ between the cone portion and the horizontal direction shown in FIG. 9 needs to be about 45 degrees for a fluid medium such as limestone, which increases the height h of the inverted truncated cone. For this reason, it was necessary to take measures such as raising the entire facility or creating an underground structure below this part.

The present invention has been made in view of the above points, and the wind box main body is divided into three or more sections by partition walls, and the air distribution plates are placed on opposite sides of the furnace main body on the left and right sides of the partition walls of the wind box main body. The central air distribution plate is formed to be inclined downward from both side walls of the furnace body to the left and right partition walls of the central wind box, and the air distribution plate in the central part is formed from both opposite side walls that are different from both opposite side walls of the furnace main body. The air dispersion plate is formed so as to be inclined downward toward the center of the furnace, and an incombustible material discharge port is provided in the center of the furnace, or the air distribution plate in the center is formed so as to be tilted downward toward the center of the furnace, or the air distribution plate in the center is formed in a direction different from the opposite side walls of the furnace main body. It is formed by sloping downward from one side wall to the other side wall, and by providing an incombustible material discharge port at the lower end of the slope, the problems of the conventional technology as described above are solved, and it can also be applied to large furnaces. The purpose is to provide a possible fluidized bed combustion furnace.

[0009]

[Means for Solving the Problem] In order to achieve the above object, the fluidized bed combustion furnace of claim 1 is provided by filling a fluidized medium to form a fluidized bed, as described with reference to FIGS. 1 to 3. A furnace body 10 that burns fuel by heating the furnace body, and a wind box body 12 that is provided at the bottom of the furnace body and temporarily stores air to be supplied to the furnace body.
and an air dispersion plate 18 provided between the wind box main body and the fluidized bed, the wind box main body is divided into at least three sections of wind boxes by a vertical partition wall 14, and the air dispersion plate 18 is Both opposing side walls 10a of the furnace body substantially parallel to the partition wall 14
, 10b to the upper ends of the partition walls on both sides of the central wind box, and are formed to be inclined downward, and air supply pipes 34 each having a flow rate control valve 36 are connected to the divided wind boxes. In a furnace, the air distribution plate 1 above the central wind box
9 are formed to be inclined downward toward the center of the furnace from both opposing side walls 10c and 10d of the furnace main body that are substantially perpendicular to the partition wall 14, and a non-combustible plate is formed at the inclined lower end of the central air distribution plate 19. A feature is that a material discharge port 40 is provided.

Further, the fluidized bed combustion furnace according to claim 2 is explained with reference to FIG. wall 1
Both opposing side walls 10c, 10 of the furnace body substantially perpendicular to 4
d, instead of forming the air dispersion plate 19a on the upper side of the central wind box to be inclined downward toward the center of the furnace, the air dispersion plate 19a on the upper side of the wind box in the center is formed on one side of the furnace main body that is substantially perpendicular to the partition wall 14 that partitions the wind box main body. The air dispersion plate 19a is formed so as to be inclined downward from the side wall 10d toward the other side wall 10c, and a noncombustible material discharge port 40a is provided at the lower end of the inclined air distribution plate 19a in the center.

Furthermore, the fluidized bed combustion furnace according to claim 3 has the structure shown in FIG.
, if explained with reference to FIG. 5, in claim 1 or 2, the central wind box is divided into a plurality of sections by vertical partition walls 42 that are substantially perpendicular to the partition wall 14 that partitions the wind box main body. Air supply pipe 34 with a partition and a flow control valve 36 in each compartment
It is characterized by the connection of

0012

[Operation] The air distribution plate 18 is connected to the opposing side wall 10 of the furnace body.
Since both a and 10b are tilted downward toward the center of the furnace, the noncombustibles move toward the center of the furnace, and the noncombustibles that have moved to the center of the furnace are tilted downward by 90 degrees. The incombustible materials move toward the center or side of the furnace and are discharged from the incombustible material discharge port 40.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the drawings. However, unless there is a specific description, the shapes of the components described in this example, their relative positions, etc. are not intended to limit the scope of the present invention to these, but are merely illustrative examples. Only.

FIG. 1 is an explanatory longitudinal cross-sectional view of a fluidized bed combustion furnace showing one embodiment of the present invention, and FIG.
3 is a perspective view showing the inside of the fluidized bed combustion furnace of FIG. 1. In FIG. 1, 10 is a rectangular furnace body;
12 is a wind box body provided at the bottom of the furnace body 10, 18 is an air distribution plate, 32 is a large number of air nozzles provided on the air distribution plate, and 14 is a wind box body for dividing the wind box body 12 into a plurality of wind boxes. Partition walls, 12d to 12f are wind boxes, and 34 is an air supply pipe that is branched into three systems and connected to the wind boxes 12d to 12f, respectively. 36 is a flow control valve for adjusting the air flow rate, and 38 is a blower. 40 in FIG. 2 is an incombustible material discharge port, and 19 is an air distribution plate in the central wind box 12f.

Next, the structure of the furnace will be explained with reference to FIG. The air distribution plate 18 extends from both opposing side walls of the furnace body, that is, from both side walls 10a substantially parallel to the partition wall 14,
It slopes downward from 10b toward the center of the furnace, and is joined to the left and right partition walls 14 of the wind box 12f in the center. The air distribution plate 19 of the wind box 12f is inclined downward toward the furnace center from both opposing side walls 10c and 10d, which are different from the opposing side walls 10a and 10b of the furnace main body. It is connected to the incombustible material discharge port 40.

When fuel containing non-combustibles is burned in the fluidized bed combustion furnace configured as described above, the non-combustibles are moved to the center of the furnace by the downwardly inclined air distribution plate 18, and then moved to the center of the furnace. The air is further moved to the center of the furnace by the air distribution plate 19 , and is discharged from the incombustible material discharge port 40 .

The amount of air supplied to each of the wind boxes 12d to 12f can be freely controlled by a flow control valve 36. Although FIG. 3 shows the case where the wind box main body is divided into five parts, it may be divided into three parts if it is a small-capacity fluidized bed combustion furnace, and it may be divided into seven parts if the capacity is large. Alternatively, it may be divided into four parts. In this case, the incombustible material discharge port does not need to be provided in the center, and may be provided in an offset position.

FIG. 4 is an explanatory longitudinal sectional view of a fluidized bed combustion furnace showing another embodiment of the present invention. The wind box 12f at the center is divided by a partition wall 14 that partitions the wind box main body and a partition wall 42 that is substantially perpendicular to the wind box 12f, and in this example, the wind box 12f is divided into four sections. Each air distribution can be changed as required.

In addition, as shown in FIG. 5, the wind box 1 in the center
2f upper air distribution plate 19a from one side wall 10d of the furnace body which is approximately perpendicular to the partition wall 14 that partitions the wind box body,
It may also be formed to be inclined downward toward the other side wall 10c, and the incombustible material discharge port 40a may be provided at the inclined lower end of the central air distribution plate 19a, that is, on one side of the furnace wall.

[0020] It is preferable that the fuel be supplied from above the incombustible material discharge port, since this reduces the distance that the incombustible material moves.

[0021]

[Effects of the Invention] Since the present invention is constructed as described above, it has the following effects. (1) Since the air distribution plate is tilted downward toward the center of the furnace, incombustible materials move to the center, and the air distribution plate in the center moves the incombustibles to the center of the furnace or It moves toward one side of the furnace and is smoothly discharged from the incombustible material discharge port. (2) Due to the downward tilt of the air distribution plate in the center of the furnace,
Compact and economical structure allows non-combustible materials to be reliably discharged.

[Brief explanation of the drawing]

FIG. 1 is an explanatory longitudinal cross-sectional view of a fluidized bed combustion furnace showing one embodiment of the present invention.

FIG. 2 is an explanatory longitudinal cross-sectional view taken along line AA in FIG. 1;

3 is a perspective view showing the inside of the fluidized bed combustion furnace of FIG. 1. FIG.

FIG. 4 is an explanatory longitudinal cross-sectional view of a fluidized bed combustion furnace showing another embodiment of the present invention.

FIG. 5 is an explanatory longitudinal cross-sectional view of a fluidized bed combustion furnace showing still another embodiment of the present invention.

FIG. 6 is a perspective view showing an example of a conventional fluidized bed combustion furnace.

FIG. 7 is a perspective view showing an example of the vicinity of an incombustible material discharge port in a conventional fluidized bed combustion furnace.

8 is a sectional view of the gear in FIG. 7. FIG.

FIG. 9 is a perspective view showing another example of the area around the incombustible material discharge port in a conventional fluidized bed combustion furnace.

[Explanation of symbols]

10 Furnace main body 10a Side wall 10b Side wall 10c Side wall 10d Side wall 12 Wind box main body 14 Partition wall 18 Air distribution plate 19 Air distribution plate 19a on the upper side of the central wind box
Air distribution plate 34 above the central wind box Air supply pipe 36 Flow rate control valve 40 Incombustibles discharge port 40a Noncombustibles discharge port 42 Partition wall

Claims (3)

[Claims] 1. A furnace body (10) filled with a fluidized medium to form a fluidized bed to burn fuel, and a wind box body (12) provided at the bottom of the furnace body to temporarily store air to be supplied to the furnace body. ) and an air distribution plate (18) provided between the wind box main body and the fluidized bed, the wind box main body is divided into at least three sections of the wind box by a vertical partition wall (14), An air distribution plate (18) is inserted from both opposing side walls (10a) and (10b) of the furnace body substantially parallel to the partition wall (14),
The partition walls on both sides of the central wind box are formed by slanting downward to the upper ends, and each partitioned wind box is equipped with a flow control valve (3
In a fluidized bed combustion furnace connected to an air supply pipe (34) equipped with 6), the air distribution plate (19) above the central wind box
are formed so as to be inclined downwardly toward the center of the furnace from both opposing side walls (10c) and (10d) of the furnace body that are substantially perpendicular to the partition wall (14), and an air distribution plate ( 19
) A fluidized bed combustion furnace is characterized in that a non-combustible material discharge port (40) is provided at the lower end of the slope. [Claim 2] Air distribution plate (1
9) is formed by slanting downward toward the center of the furnace from both opposing side walls (10c) and (10d) of the furnace main body that are substantially perpendicular to the partition wall (14) that partitions the wind box main body. The air dispersion plate (19a) on the upper side of the central wind box is moved from one side wall (10d) of the furnace main body, which is substantially perpendicular to the partition wall (14) that partitions the wind box main body, to the other side wall (10c). The central air distribution plate (19a
2. The fluidized bed combustion furnace according to claim 1, further comprising an incombustible material discharge port (40a) provided at the lower end of the incombustible material discharge port (40a). 3. The central wind box is divided into a plurality of compartments by a vertical partition wall (42) that is substantially perpendicular to the partition wall (14) that partitions the wind box main body, and each compartment is provided with a flow rate control valve. (3
3. The fluidized bed combustion furnace according to claim 1 or 2, further comprising an air supply pipe (34) having an air supply pipe (34) connected thereto.