JPH1019222A - Fluidied bed incinerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluidized bed incinerator which can carry out a stable fluidized bed incineration even when a shredder dust is charged in the incinerator by preventing a stacking of an incombustible material on a perforated plate and clogging of small apertures by the material. SOLUTION: A fluid bed incinerator comprises a perforated plate 30 having a large number of small apertures 31 which is disposed in an incinerator body 5 and is inclined with an inclination angle almost equal to an angle of repose of a fluid material 20 which is a mixture of a shredder dust 6 and a fluid adding material 7, a large number of foreign material dispersing plates 32 which are protruded inwardly from the inner surface of the perforated plate 30 at positions adjacent to openings of the small apertures 31 almost in parallel with small apertures 31, and a fluid fuel supply pipe 33 which is disposed with an inclination angle almost equal to that of the small apertures 31 and has one end thereof communicated with a lower portion of the perforated plate 30. Due to such a construction, a stacking of an incombustible material on the perforated plate 30 and the clogging of small apertures 31 can be prevented, while an adverse influence which may take place on a fluidized bed 9 formed on the perforated plate 30 can be prevented so that a stable fluidized bed incineration of the shredder dust can be achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a fluidized-bed combustion furnace using so-called shredder dust as fuel, which is obtained by cutting off end-of-life vehicles and home electric appliances.

[0002]

2. Description of the Related Art For example, car shredder dust, which is produced in the process of recycling end-of-life vehicles and is made by cutting polyethylene, plastic, urethane, rubber, cloth, leather, etc. into a few mm, contains metal (iron, aluminum). Num, copper, etc.) have been removed and used as fuel for fluidized bed combustion furnaces. However, the removal of metals in the car shredder dust to be incinerated is not complete, but is usually mixed in some amount.

FIG. 3 shows a conventional fluidized bed combustion facility using such car shredder dust as fuel. As shown in the figure, a fluidized-bed combustion furnace 21 that performs combustion in such a fluidized-bed combustion equipment 1 sandwiches a perforated plate 3 provided with a large number of pores 2, a wind box 4 downward, and a combustion chamber upward. Each of the furnaces 5 is arranged. Fuel from shredded scrap car 6 supplied from fuel supply equipment not shown
Similarly, the fluid material 7 made of limestone, sand, and the like, which is supplied from a fluid material supply facility (not shown), is separately charged into the fluid fuel supply pipe 17 and mixed while being transported by the transport air 19. , Is supplied on the perforated plate 3 as a flowing fuel 20.

On the other hand, combustion air 8 supplied from a blower
Flows into the wind box 4 and flows upward, and is supplied into the combustion furnace 5 through the fine holes 2 provided in the perforated plate 3 partitioning the upper part of the wind box 4. The flowing air 20 supplied onto the perforated plate 3 by the combustion air 8 having the upward velocity vector
Forms a fluidized bed 9 and is sufficiently mixed with the combustion air 8 to burn. After the combustion, the incombustible solids and ash remaining on the perforated plate 3 flow through the extraction pipe 10 provided at the center of the perforated plate 3 and flow through the hopper 12 by operating the valves 11a and 11b. It is discharged outside the bed combustion furnace 21.

[0005] Particles 13 such as fly ash that have flown out of the combustion furnace 5 are collected by a cyclone 14 and are sealed.
Enter 5. Particles 13 flowing into this seal pot 15
Is fluidized by the fluidizing medium 16 supplied from the bottom surface of the seal pot 15 and returned to the combustion furnace 5 again at the seal pot outlet pipe 18.

[0006] The fluid fuel 20 incinerated in the fluidized bed combustion furnace 21 contains a small amount of metals and incombustible solids as described above. In particular, metals have a large specific gravity among the fluid fuels 20, and therefore move downward and downward in the fluidized bed 9 formed by the fuel air 8, and finally flow in from the wind box 4. The air accumulates on the perforated plate 3 against the blowing force of the combustion air 8,
May be clogged in the pores 2 formed in the hole.

In addition, the amount of these metals is limited
Fluidized bed combustion equipment 1
When the is operated for a long time, the amount thereof gradually increases, and the metals staying on the perforated plate 3 or the metals clogging the pores 2 prevent fluidization of the flowing fuel 20 in the combustion furnace 5. It works. For this reason, in the fluidized bed 9, a local temperature rise or fall occurs, causing unstable combustion in the combustion furnace 5, or solidification of combustion ash, so-called, Clinkers may be generated and stable fluidized bed combustion may not be maintained.

[0008] Fluid fuel 20, which is conveyed in the fluidized fuel supply pipe 17 by the carrier air 19 and supplied to the upper part of the perforated plate 3, is charged near the upper part of the fluidized bed 9 formed in the combustion furnace 5. Thus, since the opening of the fluidized fuel supply pipe 17 into the combustion furnace 5 is provided, stable fluidized bed combustion may not be maintained. That is, since the fluidized bed 9 is formed by the combustion air 8 and the fluidized fuel 20 is supplied at random from above the fluidized fuel 20 which is supplied with sufficient combustion air 8 and is burning,
It is also conceivable that the fluidized bed 9 formed in the combustion furnace 5 becomes non-uniform, so that stable fluidized bed combustion cannot be maintained.

As described above, when stable fluidized-bed combustion in the combustion furnace 5 cannot be maintained, the temperature at the bottom of the combustion furnace 5, that is, near the upper surface of the perforated plate 3 decreases, and the combustion temperature in the fluidized bed 9 decreases. It is conceivable that the temperature decreases and combustion worsens, and that harmful substances are generated by low-temperature combustion.

[0010]

SUMMARY OF THE INVENTION The present invention is directed to a fluidized bed combustion facility, particularly to a fluidized bed combustion furnace, which is included in fluidized fuel in order to solve the problem, and the operating time is increased. Metals and incombustible solids contained in the fluidized fuel, which prevent fluidization of the supplied fluidized fuel and cause unstable combustion in the incinerator, accumulate on the perforated plate or in the combustion furnace. In order to supply combustion air, the clogging of pores formed in the perforated plate is reduced so that stable fluidized-bed combustion is maintained, the combustion temperature is maintained, and the combustion of fluidized fuel is performed. It is an object of the present invention to provide a fluidized-bed combustion furnace that prevents generation of harmful substances due to air.

[0011]

Therefore, the fluidized bed combustion furnace of the present invention has the following means.

(1) A large number of pores are formed in which a shredder-dusted fuel and a fluid material for facilitating the flow of the fuel are mixed, and a large number of pores are formed at substantially the same angle of repose as the flowing fuel. A perforated plate shaped like a funnel was provided in a combustion furnace. When car shredder dust is used as fuel, the angle of repose of the flowing fuel is usually 40 ° to 50 °. Therefore, when car shredder dust is used as fuel,
The pores formed in the perforated plate may be formed in the perforated plate so that when the perforated plate is installed in the combustion furnace, the inclination angle is approximately 40 ° to 50 ° from the horizontal plane. In other words, this angle of repose, if the type of shredder dust changes, the angle of repose of the flowable fuel mixed with the shredder dust also changes, the inclination angle of the pores when incinerating such flowable fuel, An inclination angle corresponding to the angle of repose of those flowing fuels,
It is desirable that the inclination angles are substantially equal.

[0013] The inclination angle of the funnel-shaped perforated plate when installed in the combustion furnace can be arbitrarily changed according to design conditions. It is preferable to provide an extraction pipe for discharging non-combustible solids and ash remaining in the incinerator later. Further, the pores formed in the perforated plate are provided in a plurality of stages in the inclination direction of the perforated plate in consideration of the height of the fluidized bed formed in the combustion furnace, and provided in a plurality of rows in the circumferential direction of the perforated plate. For fuel combustion,
It is desirable that an opening area capable of supplying a sufficient amount of combustion air can be secured.

(2) The hole is arranged so as to be substantially parallel to the direction in which the holes are formed in the perforated plate. A foreign matter dispersion plate protruded more inward was provided. In addition, the foreign substance dispersion plate is installed such that a plate having a width substantially equal to the width of the pore is set to be substantially the same as the inclination angle of the pore from just above the opening of the pore, and is projected to the inside of the perforated plate. Is preferred.

(3) The slant is made substantially parallel to the direction in which the pores formed in the perforated plate are formed, and one end is opened at the lower end of the perforated plate to supply the flowable fuel onto the lower end of the perforated plate. Fluid fuel supply pipe was provided. In addition, the fluid fuel supply pipe is preferably configured such that the fuel and the fluid supplied from the middle of the pipe can be mixed with the transporting internal air that is caused to flow inside, and transported to the perforated plate. . Further, it is preferable that the seal pot outlet pipe for returning the particles flowing into the seal pot into the combustion furnace has the same inclination as the fluid fuel supply pipe, and one end side is connected to the lower end of the perforated plate.

Since the fluidized bed combustion furnace of the present invention has a large specific gravity due to the above-described means, it moves downward and downward in the fluidized bed formed by the combustion air and accumulates on the perforated plate. Or when burning a flowing fuel containing a large amount of a metal or an incombustible solid having a large specific gravity that acts to prevent fluidization of the flowing fuel in the combustion furnace by clogging pores formed in the perforated plate. Even in the case of operating the fluidized bed combustion equipment for a long time, the non-combustible solids mixed in the fluidized fuel are substantially in the form of fluidized fuel inside the porous plate from the pores formed in the porous plate. At the angle of repose, it is dispersed by the combustion air blown downward and is actively blown down to the center of the lowermost end of the funnel-shaped or mortar-shaped perforated plate, so that it does not stay in the middle of the perforated plate At the same time, penetrate the pores and clog the pores Things like is eliminated.

Further, the clogging of the pores with non-combustible solids such as metals moving down the pores can be reliably prevented by the foreign matter dispersion plate provided in the vicinity of the opening of the porous plate.

As a result, the fluidization of the fluidized fuel in the combustion furnace is not hindered, and the temperature rises or falls locally within the fluidized bed, causing unstable combustion. It does not occur and clinker does not occur, and stable fluidized bed combustion can be maintained.

Further, the flowing fuel which is transported in the fluidized fuel supply pipe by the carrier air and supplied to the upper portion of the perforated plate is provided below the fluidized bed formed in the combustion furnace, that is, at the lower end of the funnel-shaped perforated plate. The opening of the fluidized fuel supply pipe into the combustion furnace is provided so as to be charged into the section, so that the combustion of the fluidized bed formed by the combustion air in the combustion furnace is inhibited by the charged fuel. Such a situation is eliminated, and stable fluidized bed combustion can be maintained.

Thus, in the fluidized bed combustion furnace of the present invention,
The combustion temperature in the fluidized bed in the combustion furnace becomes stable, and the operating efficiency of the fluidized bed combustion equipment improves,
Generation of harmful substances such as chlorine gas due to low-temperature combustion can be reliably prevented.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a fluidized bed combustion furnace according to the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing a first embodiment of a fluidized bed combustion furnace according to the present invention with a part cut away, and FIG. 2 is a sectional view taken along the line AA shown in FIG. In these figures, the same parts as those in the conventional fluidized bed combustion furnace shown in FIG.
The description is omitted.

As shown in the figure, a perforated plate 30 having an inclination angle determined by design conditions and having a central portion communicating with the extraction pipe 10 is installed in the combustion furnace 5 constituting the fluidized bed incinerator 35. Have been. When the perforated plate 30 is installed in the combustion furnace 5, the repose angle θ of the fuel 6 obtained by cutting the car shredder and the flowing fuel 20 obtained by mixing the flowing material 7 are provided.
= 40 ° to 50 °, and three or more pores 31 having an inclination angle substantially equal to each other are drilled along the inclined plate of the perforated plate 30 at three positions vertically and two or more positions in the circumferential direction. I have. In addition,
As the fuel 6, besides car shredder dust, household electric appliances and the like may be shredded, but iron and non-ferrous metals are desirably removed in advance as much as possible.

Immediately above the opening in which the fine holes 31 open on the inner peripheral surface of the perforated plate 30, a foreign substance dispersion plate 32 having the same width as the fine holes 31 is provided. The hole 31 is inclined from the top at an angle approximately equal to the angle of inclination of the pores 31, that is, the angle of repose θ of the flowing fuel 20, and protrudes toward the center of the perforated plate 30.

The opening of the flowing fuel supply pipe 33 into the perforated plate 30 for supplying the flowing fuel 20 onto the perforated plate 30 is as follows.
At the lower end of the perforated plate 30, the opening into the perforated plate 30 of the seal pot outlet pipe 34 for returning the particles 13 collected by the cyclone 14 to the inside of the combustion furnace 5 is also provided.
0 is provided at the lower end. The fluid fuel supply pipe 33 and the seal pot outlet pipe 34 are provided with an inclination angle of the pore 31, that is, an inclination substantially the same as the angle of repose of the fluid fuel 20.

Since the fluidized bed incinerator 35 of the present embodiment is constructed as described above, the fuel 6 made of car shredder dust and the fluidized material, limestone, supplied from a fuel supply facility (not shown), The flowing material 7 made of sand or the like becomes a flowing fuel 20 while being mixed with the carrier air 19.
The liquid is supplied to the lower end portion in the funnel-shaped perforated plate 30 through the flowing fuel supply pipe 33. The flowing fuel supply pipe 33 is
Since the fuel is disposed at an angle of repose greater than the angle of repose (40 ° to 50 °) from the combustion furnace 5, the fluidized fuel 20 is smoothly supplied below the fluidized bed 9.

On the other hand, the combustion air 8 supplied from a blower (not shown) flows into the wind box 4, passes through the inclined fine holes 31, flows downward at a substantially repose angle θ, and is supplied into the combustion furnace 5. You. The reverse flow of the combustion air 8 flowing downward into the combustion furnace 5 causes the fluid
Is blown up to form a fluidized bed 9 and burn. Also,
The fluidized fuel 20 mixed with the car shredder dust 6 supplied from the fluidized fuel supply pipe 33 is supplied to the funnel-shaped perforated plate 30.
Is supplied near the bottom of the perforated plate 30
At the time of upward charging, the fuel can be uniformly mixed with the fluidized fuel 20 during combustion without hindering the formation of the fluidized bed 9, and stable combustion can be continued.

Ash and incombustible solids such as car shredder dust 6 after combustion are blown down from the bottom of combustion furnace 5 by combustion air 8 at an angle substantially equal to the angle of repose.
1 collides with the foreign substance dispersion plate 32 pierced from the inner peripheral surface of the perforated plate 30 above the opening, is efficiently dispersed, falls, and passes through the extraction pipe 10 provided at the center of the funnel-shaped perforated plate 30. By operating the valves 11a and 11b, the gas enters the hopper 12 and is discharged out of the fluidized bed combustion furnace 35.

The angle of repose θ = 40 from the bottom of the combustion furnace 5
A fine pore 32 having an angle of about 50 °
The foreign matter dispersion plate 32 is disposed at the upper end of the second plate 2, and the foreign matter dispersion plate 32 is disposed parallel to the inclined pores 32, so that foreign matter and ash do not stay on the perforated plate 30. In addition, it is possible to prevent foreign matters and ash from accumulating in the inclined fine holes 31.

The particles 13 containing unburned components that have flown out of the combustion furnace 5 are collected by the cyclone 14 and enter the seal pot 15. Particles 1 flowing into this seal pot 15
3 is fluidized by the fluidizing medium 16 flowing into the seal pot 15, passes through the seal pot outlet pipe 34, and is returned to the combustion furnace 5 again.
Are opened near the bottom surface of the funnel-shaped perforated plate 30 and are arranged at an inclination substantially equal to the angle of repose from the bottom surface of the combustion furnace 5, so that the particles 13 supplied from the seal pot outlet pipe 34 are provided. Can be smoothly mixed with the fluidized fuel 20 in the fluidized bed 9 and can be stably burned.

As described above, in the fluidized bed combustion furnace 35 of the present embodiment, the combustion in the combustion furnace 5 becomes stable, and the combustion temperature in the fluidized bed 9 can be made stable. 1, the operating efficiency is improved, and the generation of harmful substances such as chlorine gas in low-temperature combustion, which is caused by unstable combustion, can be reliably prevented.

[0031]

As described above, according to the fluidized bed combustion furnace of the present invention, a fuel composed of shredder dust, which forms a fluidized bed in the combustion furnace and burns, can be provided by the structure described in the claims. , A fluid fuel comprising a fluid mixed to fluidize the fuel can be promptly and uniformly dispersed in the combustion furnace, and after the combustion of the fluid fuel,
Prevents deposits of metals and other materials remaining in the combustion furnace on the perforated plate or forms a fluidized bed and clogs the pores opened in the perforated plate to supply combustion air for burning fluid fuel However, it can be operated stably in the same manner as a fluidized bed combustion device that operates by supplying normal fuel.

Further, the use of the inclined pores and the foreign substance dispersion plate can more reliably prevent the foreign substances from being clogged in the pores 21, and can be transported in the flowing fuel supply pipe by the transport air. Fluid fuel supplied to the upper part of the perforated plate is injected into the lower part of the funnel-shaped perforated plate below the fluidized bed formed in the combustion furnace, that is, formed by the combustion air in the combustion furnace. The combustion of the fluidized bed is not hindered by the input of the fluidized fuel.

Therefore, in the fluidized bed combustion furnace of the present invention, the combustion temperature in the fluidized bed in the combustion furnace becomes stable, the operation efficiency of the fluidized bed combustion equipment is improved, and the generation of harmful substances due to low temperature combustion is reduced. , Can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a side view showing a first embodiment of a fluidized bed combustion furnace according to the present invention, with a part thereof cut away.

FIG. 2 is a sectional view taken along the line AA shown in FIG.

FIG. 3 is a side view showing a conventional fluidized bed combustion furnace with a part thereof cut away.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fluidized bed combustion equipment 2 Pores 3 Perforated plate 4 Wind box 5 Combustion furnace 6 Fuel (car shredder dust) 7 Fluid 8 Combustion air 9 Fluidized bed 10 Extraction pipe 11a, 11b Valve 12 Hopper 13 Particles 14 Cyclone 15 Seal pot Reference Signs List 16 fluidization medium 17 fluidized fuel supply pipe 18 seal pot outlet pipe 19 transport air 20 fluidized fuel 21 fluidized bed combustion furnace 30 perforated plate 31 pore 32 foreign matter dispersion plate 33 fluidized fuel supply pipe 34 seal pot outlet pipe 35 fluidized bed incineration Furnace

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location B09B 3/00 F23C 11/02 312 F23C 11/02 312 B09B 3/00 303L

Claims (1)

[Claims] In a fluidized-bed combustion furnace in which fluidized fuel obtained by mixing shredder-dusted fuel and fluidized material on a perforated plate is fluidized by combustion air and burned, the angle of repose of the fluidized fuel is substantially equal to the angle of repose. A plurality of pores having the same inclination are bored, and the funnel-shaped perforated plate disposed in the combustion furnace,
It is inclined substantially parallel to the pores, a foreign substance dispersion plate protruding from the vicinity of the opening of the pores on the inner peripheral surface of the perforated plate, and is inclined substantially parallel to the pores, and one end side is A fluidized-bed combustion furnace, comprising: a fluidized-fuel supply pipe that opens to the lower end of the perforated plate and supplies the fluidized fuel onto the perforated plate.