JP2000230709A - Multi-fuel fired furnace for sludge having rotary sludge cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-fuel fired furnace for sludge causing no environmental pollution, which is able to completely combust sludge having high water content without checking a combusting condition of the furnace and does not require auxiliary combustion. SOLUTION: A sludge cutting device 3 which is mounted on a ceiling 12 made of a refractory material of an incinerator body 1, comprises a sludge feeding chamber 31 having a sludge feeding port 36 for evenly feeding the sludge, a sludge receiving face 32 forming a bottom face of the chamber 31 and punched with a plurality of dropping holes 33 therein which are communicated with the inside of the body 1, a rotary blade 34 which is located in the chamber 31 and rotated while being slid on the face 32 by a drive means 4, and a discharge tube 35 for discharging a gas W in the chamber 31 to a recombusting chamber. Water-containing sludge Sw is fed to the face 32 whose temperature has been raised by the combustion of refuse R, and thinly extended by the rotary blade 34 while being heated and dried to fill the dropping holes 33 therewith, followed by injecting compressed air from an air injection hole in the rotary blade 34. In this way, half dried sludge Sd in the dropping holes 33 is completely combusted together with the refuse R.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sludge co-firing furnace for simultaneously incinerating refuse and sludge such as general waste and industrial waste.

[0002]

2. Description of the Related Art Conventionally, sludge discharged from a sewage treatment plant or human waste treatment plant is incinerated in a dedicated incinerator at each treatment plant or carried into a garbage incinerator installed by the same local government. It was common to incinerate by mixing with waste.

[0003]

However, Japanese Patent Application Laid-Open No. Hei.
As disclosed in Japanese Patent No. 05214, even when sludge is dispersed and charged on the surface of a garbage layer by a sludge dispersion charging device, the water content of the sludge carried in after each dewatering treatment in each treatment plant is 75 to
Since it is as high as 85%, the combustion state of each incinerator decreases and becomes very unstable.

[0004] Therefore, not only does it cause pollution such as foul odors and dust emission due to incomplete combustion, but also causes an increase in unburned components remaining in the incineration ash.
Even if the temperature of the exhaust gas and the inside of the furnace was increased by using the auxiliary burner, the above-mentioned pollutions could not be completely eliminated despite the increased fuel cost.

FIG. 5 shows a "method of co-firing dry sludge and municipal solid waste" disclosed in JP-A-64-54113.
The hydrated sludge Sw is put into the dryer D, dehydrated and dried, and then compression-molded by the pressure roller P installed at the outlet of the dryer D to become a plate-shaped dry sludge Sd.

The municipal solid waste R is incinerated in the incinerator F. In this method, the plate-shaped dry sludge Sd is mixed and burned on the burning municipal solid waste R layer.

According to the above-mentioned method, sludge containing a large amount of water, which has been a problem of the prior art, drops from the gap of the grate, and when dried into a powder form, sludge powder rides on the exhaust gas stream and is not burned. Although it solves the problem of being discharged as it is, it is necessary to install a sludge drying facility in order to improve the combustion state, equipment costs and installation area increase, and it is difficult to treat the odor generated during sludge drying. There was a problem.

[0008]

According to the first aspect of the present invention, there is provided a sludge co-firing furnace having a rotary sludge cutting device, wherein sludge is mixed with refuse such as general waste and industrial waste and simultaneously incinerated. In the co-firing furnace, a sludge cutting device is mounted on the refractory ceiling of the incinerator main body, and the sludge cutting device has a sludge supply chamber having a sludge inlet for supplying sludge on average,
A sludge receiving surface, which forms the bottom surface of the sludge supply chamber and is provided with a plurality of drip holes communicating with the inside of the incinerator main body, is disposed in the sludge supply chamber, and slides on the sludge receiving surface by driving means. It comprises a rotating blade and a discharge pipe for discharging gas generated in the sludge supply chamber to the reburn chamber.

According to a second aspect of the present invention, there is provided a sludge co-firing furnace having a rotary sludge cutting device, wherein the rotary blades are arranged to be inclined at a certain angle with respect to a rotation direction, and a lower end of the rotary blades is provided. Has a plurality of air injection holes for discharging sludge downward from the dropping holes and supplying compressed air for cleaning the subsequent dropping holes.

According to a third aspect of the present invention, there is provided a sludge co-firing furnace having a rotary sludge cutting device, wherein a discharge member replaceably disposed on the sludge receiving surface is fitted into the dropping hole for processing. It is designed to arrange different shapes depending on the properties of sludge.

[0011]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing a schematic configuration of a sludge co-firing furnace having a rotary sludge cutting device according to the present invention.
2 is a plan view of the upper part of the sludge supply chamber, FIG. 3 is a plan view of the rotating blades and the sludge receiving surface in the sludge supply chamber, and FIG. 4 is a sectional view taken along line XX of FIG.

In FIG. 1, reference numeral 1 denotes a vertical incinerator main body surrounded by a refractory 11, and a ceiling 12 is provided immediately above the incinerator main body 1, and primary combustion chambers 13 and 1 are provided below the ceiling 12 below the ceiling 12. A secondary combustion chamber 14 is formed adjacent to the secondary combustion chamber 13.

The lower part of the incinerator main body 1 connected to the primary combustion chamber 13 has a main combustion zone 1 whose boundary fluctuates as combustion proceeds.
5, a combustion zone 16 and a combustion completion zone 17 are formed respectively.
A recombustion chamber 19 is connected via 8.

A refuse input hopper 23 having an upper damper 21 having a normal structure and a lower damper 22 having a heat-resistant structure is attached to a side wall of the incinerator main body 1, and a combustion complete zone 17 below the incinerator main body 1 is provided below the incinerator main body 1. At the middle position, garbage support plates 24, 24 which can come and go, and invertible ash discharge plates 25, 25, which are also reversible, are provided at the lower end of the combustion completion zone 17.

Further, for each of the above combustion zones and combustion chambers,
Main combustion air 26, post-combustion air 27, secondary combustion air 28, and re-combustion air 29 are supplied, respectively.

Here, a sludge cutting device 3 is mounted on a ceiling portion 12 of the incinerator main body 1 which is made of a refractory material 11.

The sludge extracting device 3 includes a sludge supply chamber 31, a sludge receiving surface 32 forming a bottom surface of the sludge supply chamber 31, and having a plurality of drip holes 33 formed therein and communicating with the inside of the incinerator main body 1.
Rotating blades 34 disposed in the sludge supply chamber 31 and rotating while sliding on the sludge receiving surface 32 by the driving means 4;
A discharge pipe 35 for discharging gas W generated in the sludge supply chamber 31 to the reburn chamber 19;

The sludge supply chamber 31 is formed by being surrounded by an outer frame 31a installed on the ceiling portion 12, and the upper surface of the outer frame 31a is provided with the sludge supply chamber 31.
For example, a sludge inlet 36 having a trapezoidal side view for supplying sludge into the inside is formed. This sludge inlet 36
Is connected to a sludge supply pipe 37. Accordingly, the wet sludge Sw is supplied into the sludge supply chamber 31 through the sludge supply pipe 37 and the sludge inlet 36, and heats the wet sludge Sw received in the sludge supply chamber 31. Supply within 1.

The sludge receiving surface 32 is made of a wear-resistant material such as SUS.
3, are formed radially with reference to a lower drive shaft 41 described later, for example, as shown in FIG.

As shown in FIG. 4, the drip holes 33 are formed on discharge members 38, 38,... Which are removably fitted from above in mounting holes 32a formed in the sludge receiving surface 32 by appropriate fixing means such as bolts. An upper drip hole 33a formed;
A lower dropping hole 33b formed in the ceiling portion 12 corresponds to the upper dropping hole 33a.

The discharge members 38, 38,... Provided on the sludge receiving surface 32 have their upper drip holes 33a formed in an optimum shape according to the properties of the hydrous sludge Sw, as shown in an example in FIG. Are formed and each of the discharge members 38, 38,... Is replaceable.

The rotating blades 34 are, for example,
For example, two sheets are horizontally arranged along the sludge receiving surface 32 around the lower drive shaft 41 which constitutes a part of the lower drive shaft 41 as shown in FIG. Each is connected.

The rotating blades 34 are arranged so as to be inclined upward by a certain angle α from the sludge receiving surface 32 with respect to the rotating direction as shown in FIG.

The rotating blades 34 are composed of one or a plurality (two in the illustrated example) formed in a hollow shape.
A wear plate 34a, which is a consumable part, is fixed to a lower end surface serving as a sliding surface with the sludge receiving surface 32 by fixing means such as a screw, and a plurality of air injection holes 34b are provided on the wear plate 34a and the lower end surface. Perforated.

The air injection holes 34b are formed corresponding to the drop holes 33. For details, see the sludge receiving surface 3 described above.
2, a plurality of radially formed dropping holes 33 are formed so as to coincide with a row of dropping holes 33 in the radial direction. That is, in FIG. 4, four drip holes 33 are formed in a line in the radial direction, and four air injection holes 34 are correspondingly formed.
b is formed on the lower end surface of the rotary blade 34.

The discharge pipe 35 communicates the upper portion of the outer frame 31a with the reburning chamber 19, and is a gas containing high-temperature moisture and odor components generated when the wet sludge Sw is heated in the sludge supply chamber 31. W is discharged to the reburning chamber 19 through the discharge pipe 35.

The driving means 4 includes a lower drive shaft 41 connected to the axis of the rotary blade 34, an upper drive shaft 42 connected to the lower drive shaft 41, and a lower drive shaft 42 connected to the upper drive shaft 42. And a speed reduction motor 43.

As shown in FIG. 4, the lower drive shaft 41 is formed with an air passage 44 communicating with the inside of the rotary blade 34, and an air inflow hole 45 drilled toward the air passage 44. The outer periphery of the upper part of the lower drive shaft 41 in which the air inlet hole 45 is formed is surrounded by an air supply part 47 connected to a compressed air pipe 46.

The drive means 4 includes the above-described reduction motor 4
3 is provided with a position detector 48 for detecting the rotational position of the rotary blade rotating by the driving of the third blade.

Further, a high-temperature portion such as the incinerator body 1 is provided with a heat insulating material and a heat insulating material (not shown).

Next, a description will be given of the operation of the sludge co-firing furnace having the rotary sludge cut-off device configured as described above.

The refuse R input from the refuse input hopper 23
Is sequentially injected into the incinerator body 1 burning at a high temperature by opening and closing the upper damper 21 and the lower damper 22, and is supplied with the main combustion air 26 and burned in the main combustion zone 15.

Unburned gas G discharged from main combustion zone 15
a is gasified and combusted in the primary combustion chamber 13 and the combustion gas Gb
Then, secondary combustion is performed by the secondary combustion air 28 in the secondary combustion chamber 14. Then, the secondary combustion gas Gc mixed by passing through the gas swirling means 18 is introduced into the reburning chamber 19, and is completely burned by receiving the supply of the reburning air 29.

On the other hand, a sludge supply pipe 3
7 is supplied from the sludge inlet 36 into the sludge supply chamber 31 on average, and is rotated by the variable speed reduction motor 43 that adjusts the speed according to the properties of the sludge. Sludge receiving surface 3 by rotating blades 34
While being stretched thinly on the second 2, the discharge members 38, 38,... Arranged on the sludge receiving surface 32 and the plurality of drip holes 33,.

At this time, the burning of the ceiling 12
Is hot, and the sludge supply chamber 31 placed on the upper surface
The hydrated sludge Sw stretched therein is heated and dried, and the hydrated sludge Sw filled in the drip holes 33 is also appropriately dried to be semi-dry sludge Sd in a state where it is easily burned.

The water W and the gas W, which is an odor component, evaporate in the heating and drying process of the wet sludge Sw are supplied to the sludge supply chamber 31.
From the re-combustion chamber 19 via the discharge pipe 35,
A thermal decomposition process is performed together with the next combustion gas Gc.

When the rotary blades 34 are positioned in a line in the radial direction of the drip holes 33, the solenoid valve (not shown) is opened by the signal of the position detector 48, and the compressed air pipe 46, the air A plurality of air injection holes 34b provided at the lower end of the rotary blade 34 via the inflow hole 45 and the air passage 44
If compressed air A is injected from the
The dried semi-dry sludge Sd is formed into a short cylindrical shape, discharged from the drip hole 33 onto the main combustion zone 15, and incinerated together with the refuse R.

Here, the sludge combustion gas Gd discharged by the combustion of the semi-dry sludge Sd is the combustion gas Ga from the refuse R.
Is mixed into the re-combustion chamber 19 via the secondary combustion chamber 14 and the gas swirling means 18 and completely burned, and then discharged to the outside via a gas cooling facility, an exhaust gas treatment facility and the like (not shown). .

The above-described operation of injecting the compressed air A not only discharges the semi-dry sludge Sd but also cools the lower drive shaft 41 and cleans the drip holes 33.

Thus, the incineration residue of the refuse R and the semi-dry sludge Sd burned in the main combustion zone 15 is removed from the main combustion zone 1
5, the combustion zone 16 and the combustion complete zone 17 receive the supply of the post-combustion air 27 and are completely burned to produce harmless incinerated ash. The garbage support plate 24 is moved from the position indicated by the solid line to the position indicated by the alternate long and short dash line. After the upper half of the incinerated ash is held by projecting, the incinerated ash discharge plate 25 is opened from the position of the solid line to the position of the alternate long and short dash line, and the incinerated ash of the lower half is discharged to an incineration ash cooling device (not shown). .

Therefore, by repeating this operation,
The refuse R and the hydrated sludge Sw can be mixed and burned.

When the mixed combustion described above is completed, water is supplied from the sludge supply pipe 37 and the sludge supply chamber 3 of the sludge cutting device 3 is supplied.
1 After washing the dried sludge adhered to the inside, air is continuously fed into the sludge supply chamber 31 from a cooling pipe 39 connected to the sludge supply chamber 31 to increase the temperature in the sludge supply chamber 31 and the like. prevent.

In the present embodiment, the compressed air is injected into the drip hole 33 from the air injection hole 34b formed on the lower end surface of the rotary blade 34, so that the semi-dry sludge Sd filled in the drip hole 33 is filled. Is discharged onto the main combustion zone 15 in the incinerator main body 1. However, the semi-dry sludge Sd is filled from below the dropping hole 33 while the dropping hole 33 is sequentially filled with the sludge only by the rotation of the rotary blades 34. Can be sequentially dropped. Therefore, in this case, the drip hole 33
This eliminates the need for the above-described means configured to inject compressed air.

Although the incinerator body 1 has been described as a vertical incinerator, it may be an ordinary horizontal stoker furnace.
3 are arranged radially from the lower drive shaft 41 as shown in FIG. 3 so that the compressed air A is jetted when the rotary blade 34 comes over the drip hole 33. Not only the illustration, but also the injection of the compressed air A is continuous,
Intermittent control using a timer is acceptable.

[0046]

As described above, by using the sludge co-firing furnace having the sludge cutting device of the present invention, sludge having a high moisture content can be removed from the ceiling without using a special drying device. Because it can be dried in the incinerator, stable combustion of sludge and garbage can be achieved without disturbing the combustion state of the garbage in the incinerator.
There is no need to provide an auxiliary burner for raising the temperature of the exhaust gas, and fuel costs can be saved. In addition, since the equipment is simple, there is no need to increase equipment costs and installation area. Further, since the malodor due to the drying of the hydrous sludge is thermally decomposed in the reburning chamber, the malodor is not released to the outside.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a sludge incinerator having a rotary sludge cutting device according to the present invention.

FIG. 2 is a top plan view of a sludge supply chamber.

FIG. 3 is a plan view of a rotating blade and a sludge receiving surface in a sludge supply chamber.

FIG. 4 is a sectional view taken along line XX of FIG. 3;

FIG. 5 is a cross-sectional view showing a schematic configuration of a conventional sludge co-firing furnace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Incinerator main body 12 Ceiling part 3 Sludge extraction device 31 Sludge supply chamber 32 Sludge receiving surface 33 Dripping hole 34 Rotating blade 35 Discharge pipe 36 Sludge inlet 4 Driving means R Garbage Sd Semi-dry sludge Sw Wet sludge W Gas

Claims (3)

[Claims] Claims: 1. A sludge co-incinerator for mixing and incinerating sludge into garbage such as general waste and industrial waste, wherein a sludge extracting device is mounted on a refractory ceiling of the incinerator body; The sludge cutting device includes a sludge supply chamber having a sludge inlet for supplying sludge averagely, and a sludge formed with a bottom surface of the sludge supply chamber and a plurality of drip holes communicating with the inside of the incinerator main body. Receiving surface, rotating blades disposed in the sludge supply chamber and rotating while sliding on the sludge receiving surface by the driving means,
And a discharge pipe for discharging gas generated in the sludge supply chamber to the reburning chamber. 2. The rotating blade is arranged to be inclined at a certain angle with respect to the rotation direction, and at the lower end of the rotating blade, sludge is discharged downward from a drip hole, and the subsequent dripping is performed. 2. A sludge co-firing furnace having a rotary sludge cutting device according to claim 1, wherein a plurality of air injection holes for supplying compressed air for cleaning the holes are perforated. 3. A discharge member replaceably disposed on the sludge receiving surface is fitted into the drip hole, so that a sludge having a different shape can be disposed depending on the properties of the sludge to be treated. A sludge co-firing furnace having the rotary sludge cutting device according to claim 1.