JPS5843318A - Discharging device for fluidized bed incinerator - Google Patents

Abstract

PURPOSE:To enable to discharge incombustible substance from a fluidized bed incinerator without the occurrence of bite, by using a screw conveyor of which screwed vanes are specifically assembled, being connected to discharge ports at both ends of refuse dispersing plates, slantedly fitted to the bottom of a furnace, as a discharger to discharge incombustible substance from a fluidized bed incinerator. CONSTITUTION:The fluidized air fed from a blower 7 is injected into a furnace, upwardly from a dispersing plate 8, to fluidize a fluidizing medium such as sand, and the dust being fed from a dust feeder 5 is fed onto the fluidized medium, in the incinerator 6 of an incinerating equipment for city refuse. In the incinerator 6 built in such a manner, sharply sloped shooters 22, connected to discharge- ports 21 to discharge incombustible substance, are provided to the lowest ends of a dispersing plate 8, slantedly fitted to the bottom of an incinerator 6, and a screw conveyor 23 is connected to its lower ends. The screw conveyor 23 is composed in such a manner that a screw 28, provided with a pair of twisted vanes 27, twisted to the opposite direction to each other, to the outer periphery of an axis 26, is housed in a tubular casing 25, which is provided with an outlet 32 to the center part thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a discharge device for discharging incombustible materials from a fluidized bed incinerator for incinerating urban areas.

``In recent years, fluidized bed incinerators, which have better combustion efficiency than stoker incinerators, have come into use as waste incinerators. Has a swirling fluidized bed.

In a fluidized bed incinerator, the fluidization of the fluidized bed is not inhibited even if relatively large incombustibles are mixed in.
Also, combustible materials can be burned efficiently without crushing them.

Therefore, furnaces of this type □ are often used5. - However, in a screw conveyor that is normally used as a device for discharging non-combustible materials, the large size 11 receivers may become jammed with iron pieces contained in the non-combustible materials, causing damage or rendering the conveyor inoperable.

On the other hand, if the sealing of the furnace internal pressure is incomplete, gas leakage from the gland packing may occur, leading to an accident.

In the conventional screw conveyor, the fluid medium is sand and non-combustible materials (to-Jo in the sand).

Since it had two functions: transportation and furnace pressure sealing, it was desired to make the tally balance between the screw vane and the casing as small as possible, and it was set to about J~10-. For this reason, although the sealing effect of the furnace internal pressure is ensured, if a piece of iron gets caught in the narrow gap, it may become impossible to change the situation.
It is difficult to restart, which significantly reduces production efficiency, and it is not easy to maintain and overgrowth.

In the present invention, the height of the incinerator 0: i discharge 01C connection 1 shade is set to be larger than the static height of the fluidized bed in the incinerator (preferably the height of the fluidized bed at rest x the apparent specific gravity of sand). Also big and shi) especially shi.

It is an object of the present invention to provide a discharge device which eliminates the above-mentioned drawbacks of the conventional device, does not cause jamming even when extremely hot non-combustible materials are mixed in, and is capable of sufficiently sealing the furnace internal pressure. That is.

The present invention provides a discharge device for discharging noncombustibles from a fluidized bed incinerator, including a chute whose upper end is connected to a noncombustibles discharge port of the fluidized bed incinerator and which guides the noncombustibles to fall by gravity, and a lower end of the chute. a screw conveyor with an inlet connected to the incinerator, and the height of the shade is greater than the static height of the fluid in the fluidized bed incinerator.

The screw blades for transporting sand and non-combustible materials start at a position on the transport direction side from the side wall on the transport direction side of the entrance of the screw conveyor.
A screw is installed in Maruyo 5, and furthermore, the counter-axial feed direction starts just below the inlet! ″ with small diameter screws: with or without screw blades, with a rounded inclined casing for smooth sand flow, and with sufficient air space between the screw blades for transportation and the casing of the screw conveyor. It has a large lf# image.

The present invention will be explained using the drawings with reference to the embodiments.
The figure is an example of what can be installed in a municipal waste incineration facility.
The 9 and 9 stored in the hopper were dumped into the hopper by the crane's packet J, and the dust supply device,! It is intended to be supplied to the incinerator 6. In the incinerator 6, the fluidized air supplied by the blower blows out from the dispersion plate t upward into the furnace, and when it hits the inclined wall, it becomes a swirling flow io in the buried vertical plane, dispersing sand, etc. A swirling fluidized bed is formed by flowing and moving a fluidized medium through this.

Furthermore, there is a downwardly moving K layer in the center of the furnace! This swirling fluidized bed, descending movement, layer pipes, and waste can be burned efficiently in a short period of time, and even if crushing is not performed in advance, high combustion efficiency can be achieved without impeding fluidization. Obtainable.

ll is the combustion exhaust gas duct, l is the incombustible material discharge port, /J
is a vibrating sieve, /41 is a conveyor for discharging lumpy incombustibles, and / is an elevator for collecting fluidized media such as sand.

Feeding device! , 16 is an inlet for garbage, 1 is a sand bag, an outlet for destroyed and leftover garbage, an outlet for large non-combustible materials that are not allowed to enter the incinerator 6, and 19 is a return chute.

The dust supply device I was invented by the inventors, for example, in the Showa era! A structure as shown in the specification of the dust supply device filed on 17th January 2015 is used.In other words, one screw with opposite helical directions rotates in parallel and in opposite directions. The expansion force that tries to push and spread the one screw i due to the trapped debris exceeds a predetermined allowable expansion force for the distance between the axes of the one screw. The axis-to-axis distance is adjusted so that the distance between the two screws does not exceed the allowable expansion force, and even if the distance between the two screws reaches the maximum distance in steady state, the expansion force still exceeds the allowable expansion force. In the pigeon house, the single screw rotates in the opposite direction for reverse transport, and the distance between the shafts is increased by 1 from the maximum distance between the shafts in the steady state, so that the foreign matter is reversely transported and discharged. It's Nishide.

With the dust supply device 3 having such a configuration, it is not necessary to crush the garbage in advance, and the garbage can be supplied to the incinerator 6 by simply tearing and destroying the bags by the dust supply device S, and combustible materials can be Even non-combustible items and large items are allowed to pass through.

A pair of screws configured as described above may be arranged side by side.

Next, an embodiment of the incombustible material discharging device/J of the present invention will be described.

In FIGS. 2 and 3, a steep slope is connected to the lowest end of the inclined dispersion plate t at the bottom of the incinerator 6, and is connected to a discharge port J/ for discharging noncombustibles, and guides the noncombustibles to fall by gravity. A sloping slope has been established. A screw conveyor JJ is connected to the lower end of the sheet conveyor.

The 9th figure is a vertical cross-sectional view of the screw conveyor, and the 9th figure is the 9th one.
＠1″Part-＠ ,,',The 1st is the 1st part of the figure 0-W′
"I!!Q, II7@t"C0"-"-. Fixed to machine base J41, nine cylindrical casing J! The shaft roller is equipped with a pair of nine threaded blades J7 having a large diameter on the outer periphery and twisted in opposite directions, and nine screw blades t are inserted into the shaft roller. A journal part 4a fixed to both ends of the shaft J6 is fitted into the nine bearings, and the shaft rollers are supported, and the journal part AIL end is driven by a drive source (not shown). Chain wheel Jl is fixed. The axial center of the screw col has no screw blades, and an outlet JJ is provided below it.

The outer circumference of the screw vane knob and the casing! The air space 11G between the inner wall of It has about θ~-〇〇-. Slanted casing J4I with an inclination JIIJJ of slope (am-411 to 700) following the flow of sand is fitted into both ends of casing Co.9, and casing J9 □Overlap the end plate sj that is integrated with the stand J0 of I, and attach the inclined cage → −Deng J,
End plate 3! is casing J! It is fixed to the end plate J! A stuffing box J4 is formed in the center of the stuffing box J6, and a shaft sealing material 3 is fitted into the stuffing box J6.
A packing presser l is provided so that it can be propelled towards.

Inclined casing J# is the end flange part for installation mentioned above] Casing J! There is a slight gap between the 9 cylindrical outer circumferential material and the outer periphery of the screw wing @, and the cylindrical inner circumferential material with a small gap between the two and the slanted wall whose upper part is square and whose lower part is oval as shown in Figure 7. It is made from J.J. The screw blade 30 protrudes slightly below the chute as shown. screw wing t
lJt starts on the transport direction side, almost directly below the side wall Jjt) of the inlet Jj& of the casing Jj in the direction in which the objects to be handled are conveyed by the screw blades.

The action of the screw blade J0 is to prevent sand from moving toward the stuffing box J6 and damaging the shaft sealing device, and its twisting direction is the same as that of the screw blade on the same side.

Therefore, it is possible to eliminate the screw wing @SO and fit it with the inner circumferential tube shaft -6 of the inclined casing J41 with a small gap to prevent the sand from moving toward the stuffing box J4.
t, 410 covers the inspection port of casing Jj and casing-! This is a cover fixed to the 41J is a pair of grooves 1A6 provided on the outer periphery of the journal part JAaoyyyy.
Adjust St to connect to vibrating sieve/J. As shown in Fig. 1, the upper part of the vibrating sieve/J (non-combustible materials such as large pieces) is transferred to the conveyor/411, and the lower part (fluid medium and other non-combustible materials such as fine powder) is transferred to the conveyor/411. Separates and regenerates the fluid medium as needed to make the elevator l! It is then put into the incinerator 6 again.

The effect will be explained.

First, to explain the furnace internal pressure sealing effect, the main pressure P at the lowest part of the fluidized bed of the incinerator 6 (the lower end of the discharge port J/) changes slightly with respect to the air volume Q as shown in FIG. □ In the figure, the horizontal axis is the air volume Qm7B (cubic meter/hour) and the vertical axis is the pressure P.
shows. □The lower end of seat 11 is assumed to be at atmospheric pressure.

The pressure P at the bottom of the fluidized bed is approximately 0.000 mmAq when the fluidized bed is formed. The static height of the sand in the furnace is h
The relationship between P-Q when , is as shown by the curved line in the figure. Gmf is the air volume at which fluidization starts. Until Q reaches /Gmf, P increases almost in proportion to Q, but when it reaches lGmf, it starts to fluidize, and then the terminal velocity (during the time at the speed button trench before the sand starts to be blown up and scattered) P is almost one room.

Rounding, the first sand diameter in the fluidized bed and the chute Jλ part is the same.
As shown in the figure, depending on the sand height H of the JJ part, the relationship between P-Q of the part of the chute J is Is>h, then the HHth
When tH becomes h, the curve becomes like curve C.

That is, the sand height Hl of the chute 21 section is 11. (h′&;
b@4rawttrao′″″°,,,,,i,],□
msbm*vs+”Nyu・1− as shown at the intersection with “P”
The resistance due to the sand height Hl of the part is overcome by the pressure pmmAq due to the lowest part of the fluidized bed, and the air volume Q, which takes into account the ventilation resistance,
As shown at the intersection of the curve lsB and the pressure P at the bottom of the fluidized bed in Figure 1, the resistance due to the sand height H of the chute 22 overcomes the pressure PmmAq due to the further height of the fluidized bed.
The sand in the chute does not flow out (fluidize) and the air volume Q
, Nm''/H, which is only a very small amount of air that leaks.

Shoot bottom sand height H, (in case of h, see Figure 1)
, shoe) Since the ventilation resistance Pma due to the sand height H8 in the JJ section is smaller than the fluidized bed pressure P, the fluidized air in the fluidized bed tends to flow toward the bottom part, and some sand is in a downward fluidized state. The seal gradually descends and is no longer able to perform its sealing function.

In addition, in conventional screw conveyors, the gap between the casing and the screener blades is set to 1, and the gap between the casing and the screener blades is filled with sand.
), the height of the sand in the area of -"'l' It is necessary to maintain a sufficient height only with the sand layer height of the chute.

Shoe) JJ height H8 is greater than the static height of sand in the fluidized bed, and when the apparent specific gravity of sand is 8, a8. It is more preferable that '>h−s.

Next, the jamming prevention effect will be explained.

As mentioned above, in a fluidized bed furnace having a swirling flow in a vertical plane, even if noncombustible materials of a large size are introduced, the formation of the fluidized bed will be inhibited, and it is difficult to allow the noncombustible materials to pass through! Therefore, as a discharge device, it is necessary to smoothly transfer and discharge this large-sized incombustible material.

In the above-mentioned feeding device, the gap between each screw shaft is usually a specific size (for example, about 1 cm), and when a foreign object is caught, the maximum gap under normal conditions @-maximum distance II between axes in phase order with distance (for example, 200
Since the foreign matter is transferred while expanding at times (wm once) and t, a foreign object having a size that can pass through this maximum gap is thrown into the screw conveyor JJ.

Sp 9 &-Conveyor J entrance! Foreign matter that enters into the casing Jj enters the position directly below the entrance where there is no screw wing IIJ. Therefore, if there is sufficient clearance between the casing Jj and the shaft 16, foreign objects can be kept between the screw blades and the air in the axial direction from the starting position of the screw blades. iG and is sent to the center in the axial direction as the screw blade rotates. Toa entrance JJ & directly below it is empty because there is no screw blade richness! iGyo1
If a large foreign object enters, if there is a screw blade in that position, the foreign object may get caught between the outer periphery of the screw blade and the inside wall of the cage. Inlet corner corner of the upper semicircle of the casing Jj in the direction of transport transport due to the screw shaft l of L
What about the rotation of the screw blade tip and the screw blade IJJ? However, in this invention, since there is no screw blade 17 directly below the inlet JAIL, foreign matter enters from a part of the screw blade in the axial direction. Even large foreign objects can get in between the screw blades.

If the screw is smaller than the empty 11G, the screw 11 will be covered with waste and sand after incineration, so it will move in the axial direction and move between the casings S.
5. toward the center of the Therefore, screw wing 1 of screw Jf! J?
The transported object between the screw vanes is sent at a relatively rapid speed, and the outer periphery of the screw vane J7) casing co! The speed decreases as it moves away from the inner wall. Therefore, casing J! wear is significantly reduced. In addition, in the conventional example with a small gap G, the welfare casing
Sand trapped in the gap between the inner wall of No. 5 and the outer periphery of the screw wing II causes significant wear.

However, the present invention eliminates this phenomenon.

Among the foreign objects, those such as umbrellas, large cans, and pans are softened by high heat, and are pressed by the screw blades in the screw conveyor aJ, and are easily pressed and pressed together with other foreign objects.
Crushed and discharged/9-) Block, steel ζ iron,
(hammer heads, bullets, mechanical parts, etc.) are transported and ejected as they are without being caught.

Inclined casing J4+ with small screw wings @JO between inlet JjlL and stuffing dowel 336
Since the inner periphery of the stuffing box J6 and the outer periphery of the screw wing J6 are provided close to each other, the sand is moved in a direction away from the stuffing box J6.

In this way, when the screw blades in the center are sent to a position where there is no depth, there are no screw blades on the upper part of the exit hole J, and due to gravity, sand, foreign matter, incinerated ash, etc. fall from the screw blades on both sides to the exit hole J. do. The sand in the JJ slides smoothly into the sloping wall JJ due to gravity. 41 does not require any pushing force for repeated transportation.

In addition to the above, the present invention provides a screw-type discharge device for discharging incombustible materials from a fluidized bed incinerator, in which a screw blade for discharging is located almost on the side wall of the casing of the conveyor in the transport direction. No jamming occurs between the conveyor casing and between the screw blade outer periphery and the conveyor casing! ! Since the gap is wide open, wear of the casing and screw is significantly reduced. Since an inclined wall is provided directly below the entrance from the wall opposite to the transport direction of the entrance, the sand from the shade directly above the entrance of the screen conveyor is smoothly fed between the screw blades iJf. Sand is prevented from advancing toward the shaft sealing device because a screw blade with a small outer circumference that contacts the inner circumference of the inclined casing forming the inclined wall with a small gap is provided on the shaft of the screw.

[Brief explanation of drawings]

Figure 1 is a cross-sectional front view of the waste incineration facility, Jll and 3
The figures are a cross-sectional front view and a cross-sectional side view of an embodiment of the present invention, Fig. 3 is a vertical cross-sectional front view of the vicinity of the discharge screw conveyor of the waste incineration facility, Fig. 3 is a partially enlarged view of Fig. 6, and Fig. 6 Figure 7 is the A-A sectional view of Figure 1, Figure 7 is the sectional view of Figure 0B-BIlfr, and Figure 7 is the relationship between fluidized bed lower pressure P and air volume Q, 1sW.
It is J. l...Bit Co...Crane J...Packet Da...
・Hoppa! ...Feeding device 6...IJl?F?
...Prower L...Distribution plate D...Slanted wall IO...Swirling flow //...Combustion exhaust gas duct) /J...Incombustibles discharge device /J...Shake 111 sieve /4'...Conveyor l!
・・Elevator /4−・Entrance of garbage 17・Exit of trash it・・Discharge port 11・・Return shade J/・・
Discharge port Coco...shade CoJ...screapunveyor Coco/Φ machine stand 1t...casing 2! r&a-
Population −jb・・Side wall−6・・Axis −ri・Fist screw blade
Jf...Screw Body...Bearing JO...Screw vane Jl...Chain wheel 3-way battle/Exit JJ...Slanted wall 31M-...Slanted casing SZ...End plate J6...
・Stuffing box 3-・Shaft m material Jt・・Cover Jf-・Chute 4IO・e cover 41/・・
Patchkin presser. Patent Applicant Ebara Corporation Agent Arai - Department Figure 1 Figure 3 [ Figure 2 9 Tsukasa Figure 5 Figure 6 Figure 7 Figure 8, 7'

Claims (1)

[Scope of Claims] l A shade whose upper end is connected to the incombustible material discharge port of the fluidized bed incinerator and guides the incombustible material and sand to fall by gravity; and an inlet connected to the lower end of the shade, which In a screw-type noncombustible material discharge device for discharging noncombustible materials from an incinerator, Il on the transportation direction side of the inlet. position) A device for discharging non-combustible materials equipped with a screw whose screw blades for transportation start at a position on the transportation direction side. The incombustible material discharge device according to claim 1, wherein a gap between the outer periphery of the screw and the casing is sufficiently opened. 1. An inclined casing with an inclined wall along the flow of sand was provided directly below the entrance from the center of the lower end of the side wall in the anti-axial direction. 4I The incombustible material discharge device according to claim 1. 2. The incombustible material discharge device according to claim 1, wherein a screw blade having a small diameter is provided at one end of the screw for discharge.