JPH0972528A - Waste incinerator with sludge dryer - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] In a waste incinerator having a sludge drying device for drying sludge by utilizing the heat retained by the waste combustion exhaust gas, the dry sludge can be selected for either incineration or recycling. Control the energy balance between exhaust gas and sludge drying to maintain stable combustion in the incinerator and reduce the running cost of the heat source. SOLUTION: The combustion exhaust gas outlet 5 side of the refuse incinerator 1 and the dry sludge discharge port 10 of the rotary type sludge drying device 9 are provided facing each other, and a dry sludge input port 23 and a dry sludge discharge port 1 are provided.
0 and the dry sludge removal port 24 is provided with the dry sludge moving means 11. Further, the combustion exhaust gas is introduced into the rotary sludge dryer and the bypass flue 15 via the dampers 7 and 8 at two places.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes waste gas from combustion to remove sludge (doro or non-doro food processed meal, leftover food, animal dung, drainage screen dust, metal processed powder, and other high-moisture waste. The present invention relates to a refuse incinerator having a sludge drying device for drying

[0002]

2. Description of the Related Art Sludge generated from a water treatment device of a business establishment such as a factory is a high water content material containing 80% or more of water.
This is dried by a sludge dryer and then composted for recycling. When it is not recycled, it is further incinerated in a refuse incinerator after drying to reduce the amount of waste. At the same time, at business establishments such as factories, paper,
Combustible waste such as plastic was generated, and these were generally incinerated in a waste incinerator.

As described above, since the sludge drying device and the main body of the refuse incinerator are separately arranged, the initial cost for constructing the facility is high and a large amount of heat energy is required to dry the sludge. Moreover, incinerating the sludge after drying it without recycling it requires a large amount of energy for further incineration, which causes a running cost of the heat source for drying the sludge, which is a problem in terms of cost. For example, as described in JP-A-64-54113, when incinerating dry sludge, it is possible to increase the combustion efficiency of the incinerator by forming the dry sludge into a plate shape and co-firing with municipal solid waste. Although disclosed, there is a problem that a large amount of heat energy is separately required to dry the sludge because a sludge drying device is separately provided.

Therefore, in order to efficiently use the heat energy by supplying the heat source for drying the sludge with the retained heat of the waste combustion exhaust gas, a fixed bed incinerator which is a combustible waste incinerator and a combustion gas are blown in. Combined with a rotary sludge dryer suitable for drying sludge by rotating sludge while dropping sludge, the sludge is dried using the heat of combustion exhaust gas of combustible waste in a fixed bed incinerator. And some are designed to be incinerated.

For example, as shown in FIG. 2, a refuse fixed bed furnace 51 is provided with an inlet 52 for charging the refuse and an ignition burner 53 for burning the refuse in the furnace on the side surface of the fixed bed furnace. ing. An ash pit 55 is provided on the bottom surface of the fixed bed furnace 51 via a grate 54 to store ash of the incineration product. A combustion exhaust gas discharge port 56 for discharging combustion exhaust gas is provided on the anti-combustion burner side of the fixed bed furnace. The combustion exhaust gas discharge port 56 is rotatably connected to an outlet 58 of a cylindrical rotary sludge drying device 57 which is inclined downward toward the combustion exhaust gas discharge port.
At the other end of the rotary sludge dryer 57, a sludge inlet 59 is provided.
Also, a sludge exhaust gas port 60 is provided. The sludge exhaust gas port 60 is further connected to a chimney through a deodorizing furnace (not shown), a dust collector, and the like.

According to such an incinerator, waste is incinerated in the fixed bed furnace 51, but sludge introduced into the rotary type sludge drying device 57 from the sludge inlet is rotated in the slanted tubular portion. While falling toward the exit 58. on the other hand,
The combustion exhaust gas generated in the fixed bed furnace 51 is discharged from the combustion exhaust gas discharge port 56 to the outside from the chimney through the sludge exhaust gas discharge port 60, the deodorizing furnace, the dust collector, etc. through the cylindrical interior of the rotary sludge drying device 57. However, the rotary sludge drying device dries the sludge when passing through the inside of the cylinder. Therefore, sludge is discharged from the outlet 58.
By the time the temperature reaches
Since it fell into the fixed bed furnace 51 as dry sludge and was incinerated together with the dust, the equipment became smaller, and a great amount of heat energy was not required for drying the sludge.

[0007]

However, in the incinerator in which the combustible waste incinerator and the rotary sludge dryer are integrated, the dry sludge dried by the rotary sludge dryer is incinerated only in the fixed bed furnace. It was impossible to recycle the dried sludge. Further, the energy balance between the combustion exhaust gas energy of combustible waste and the evaporation energy of water contained in sludge is not easily balanced, and stable combustion in the incinerator cannot be maintained. Further, since the entire amount of combustion gas of the fixed bed furnace is introduced into the rotary sludge dryer, it becomes difficult to control the energy balance between the fixed bed furnace and the rotary sludge dryer.
There is a problem that the fixed bed furnace cannot perform stable combustion, and thus the drying heat source of the rotary type sludge drying device tends to become unstable.

In view of the above-mentioned problems, an object of the present invention is to incinerate or recycle dry sludge in a refuse incinerator having a sludge drying device for drying sludge by utilizing the heat retained by the waste combustion exhaust gas. Either of them can be selected, and the energy balance between flue gas and sludge drying is controlled to maintain stable combustion in the incinerator and to reduce the running cost of the heat source.

[0009]

In order to achieve the above object, the present invention provides a rotary sludge drying device on the combustion exhaust gas outlet side of a refuse incinerator with its dry sludge discharge port facing and opening. In the case of incinerating the dry sludge by the dry sludge transfer means for transporting the dry sludge across the combustion exhaust gas outlet or the dry sludge inlet opening to the incinerator and the dry sludge discharge port and the outside of the furnace, The problem was solved by putting the dry sludge into the refuse incinerator or by allowing the dry sludge to be discharged out of the furnace when the dry sludge is taken out without incineration.

At least two exhaust gas outlets of the refuse incineration section are provided, one of the combustion exhaust gas is introduced into the rotary sludge dryer from the dry sludge discharge port through a damper, and the other of the combustion exhaust gas is dried through the damper. It is recommended to introduce it into the bypass flue that bypasses the equipment.

(Operation) Sludge discharged from a water treatment device such as a factory is put into a rotary type sludge drying device and moved toward a dry sludge discharge port. Combustion exhaust gas generated from the refuse incinerator is discharged from the dry sludge discharge port through the sludge discharge port while drying the sludge through the cylinder of the rotary sludge dryer. The dried sludge that has been dried falls from the dried sludge discharge port onto the dried sludge moving means (for example, a screw conveyor that can be rotated in the normal direction). When incinerating dry sludge, it is put into the refuse incinerator by the dry sludge moving means from the combustion exhaust gas outlet or the dry sludge inlet opening in the incinerator, and when the dry sludge is reused, it is directly sent to the outside by the dry sludge moving means. Is discharged.

By adjusting dampers at two places, the first combustion exhaust gas outlet and the second combustion exhaust gas outlet of the refuse incinerator, the residual heat of the combustion exhaust gas is released to the bypass flue and the temperature inside the furnace and the first
By adjusting the amount and temperature of the combustion exhaust gas introduced into the sludge drying device from the combustion exhaust gas outlet, the waste incinerator is burned stably, and at the same time, the sludge drying heat source is stably supplied.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of a refuse incinerator having a sludge drying device of the present invention. In FIG.
Waste incinerator 1 that burns the waste that has been input from the input port 12
Is provided, and an ignition burner 13 for burning dust in the furnace is provided on the side surface. A rotary sludge dryer 9 is provided adjacent to the incinerator 1.

Below the dust dropping position of the charging port 12 in the incinerator 1, stepped fixed grate 2, 3 and moving grate 4a, 4b are provided so that the dust can be sequentially transferred to the bottom of the incinerator, and the bottom surface is provided. Is provided with an ash outlet 14 for storing and extracting incinerated ash. Two combustion exhaust gas outlets are provided above the anti-combustion burner side of the incinerator 1, the first combustion exhaust gas outlet 5 opens to the sludge drying device side, and the second combustion exhaust gas outlet 6 bypasses the sludge drying device. It is introduced into the bypass flue 15. At the first combustion exhaust gas outlet 5, a dry gas damper 7,
A bypass damper 8 is connected to the second combustion exhaust gas outlet 6.

After the dry gas damper 7, the dry sludge discharge port 10 of the rotary type sludge drying device 9 is opposed and opened so that the dry sludge is dropped and discharged from the dry sludge discharge port. A screw conveyor 11 capable of rotating in the normal and reverse directions is provided at the dropping position. One end of the screw conveyor 11 reaches a fixed sling 3 on the incineration section 1 side, a dry sludge inlet 23 that opens so that the dry sludge can be loaded into the moving grate 4b, and the other end reaches the incineration section 1, the rotary sludge dryer It reaches a discharge-side opening 24 that opens to the outside so that dried sludge can be discharged. The discharge side opening 24 is provided with a dry sludge discharge box 25 for collecting dry sludge.

At the anti-dry sludge discharge port 10 of the rotary type sludge dryer 9, a sludge inlet 16 for introducing the sludge to be dried and incinerated and a sludge exhaust gas outlet 17 for discharging the combustion exhaust gas passing through the rotary type sludge dryer. Is provided. The sludge exhaust gas outlet 17 is connected to the bypass flue 15, and is further connected to a deodorizing furnace 18 having a deodorizing burner 19, a cyclone type dust collecting furnace 20, an exhaust fan 21, and a chimney 22.

Next, the operation of the embodiment of the present invention will be described. In FIG. 1, combustible dust such as paper and plastic is thrown into the upper part of the fixed grate 3 of the incinerator body 1 from the dust throwing device 12. It The dust is ignited by the ignition burner 13 and begins to burn. Moving grate 4 as combustion progresses
a and 4b sequentially move forward and backward, dropping the combusted materials of dust to the fixed grate 2 and the lower part of the fixed grate 2 while stirring, and finally, as incineration ash 1
It is discharged to 4.

On the other hand, the combustion exhaust gas of the waste is collected at the combustion exhaust gas outlets 5 and 6 above the incineration main body 1 and introduced into the rotary sludge dryer 9 by adjusting the rotary dampers 7 and 8 and the bypass smoke. It is divided into gas introduced into the passage 15. The combustion exhaust gas introduced into the rotary sludge drying device 9 reaches the sludge exhaust gas outlet 17 while drying the sludge input from the sludge input device 16.

The sludge (moisture content: 75 to 85%) charged from the sludge charging device 16 is gradually dried in the rotary type sludge drying device 9 and has a water content of 20 when it reaches the dry sludge discharge port 10. The furnace length of the rotary type sludge drying device 9 is designed to be ˜30%, and the fine control during operation is performed by adjusting the balance of the rotary dampers 7 and 8.

The combustion exhaust gas passing through the sludge exhaust gas outlet 17 of the rotary type sludge drying device 9 is mixed again with the combustion exhaust gas introduced into the bypass flue 15 and is introduced into the deodorizing furnace 18. The combustion exhaust gas introduced into the deodorization furnace 18 is deodorized at high temperature by the heat of the deodorization burner 19, is introduced into the cyclone 20 and dust in the combustion exhaust gas is collected, and is further discharged into the atmosphere from the chimney 22 via the exhaust fan 21. Is discharged.

The sludge dried in the rotary type sludge drying device 9 falls from the dry sludge discharge port 10 and is discharged onto the screw conveyor 11. When incinerating dried sludge,
The screw conveyor 11 is rotated in the normal direction and is put into the refuse incinerator 1 through the dry sludge inlet 23 above the incinerator 1, and is mixed with combustible waste. On the other hand, when the dried sludge is taken out as dried, the screw conveyor 11 is reversed and the dried sludge is discharged to the dried sludge discharge box 25 through the dried sludge discharge port 24.

In the embodiment of the present invention, the dry sludge moving means is a screw conveyor capable of rotating in the forward and reverse directions, but it goes without saying that it may be a heat-resistant metal belt conveyor or the like. However, the screw conveyor is the first,
Combustion gas is prevented from leaking from other than the second combustion exhaust gas outlets 5 and 6, and even if the dry sludge is in powder form, it does not rise due to the gas pressure of the combustion gas, etc. It has the advantage that it can be carried out. Further, the structure of the refuse incinerator, the rotary sludge drying device 9, and the structure after the bypass flue 15 are not limited to the embodiments of the present invention and can be appropriately applied without departing from the spirit of the invention. .

[0023]

INDUSTRIAL APPLICABILITY In the present invention, the sludge is effectively dried by utilizing the heat retained by the combustion gas generated from the refuse incinerator so that the sludge can be dried without using an external heat source. Since the dry sludge transfer means was provided at the outlet so that the dry sludge can be transferred to the inside or outside of the furnace, when recycling the dry sludge, it can be taken out as it is before the incineration process, and the dry sludge can be incinerated. The present invention provides a refuse incinerator having a sludge drying device capable of incineration or recycling of dried sludge depending on resource requirements, which can be selected from either recycling or recycling.

Further, since a part of the combustion exhaust gas is damper-controlled to escape to the bypass flue, the heat balance between the refuse incinerator and the dry sludge device can be easily controlled, so that stable combustion of the incinerator can be achieved. It can be maintained, and the running cost of the heat source can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an overall configuration of a refuse incinerator having a sludge drying device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a refuse incinerator having a conventional sludge drying device.

[Explanation of symbols]

 1 Waste Incineration Section 5 First Combustion Exhaust Gas Outlet 6 Second Combustion Exhaust Gas Outlet 7 Dry Gas Damper 8 Bypass Damper 9 Rotary Sludge Drying Device 10 Dry Sludge Discharge Port 11 Dry Sludge Transfer Means (Screw Conveyor) 15 Bypass Flue 17 Sludge exhaust gas outlet 23 Dry sludge inlet 24 Dry sludge outlet

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location F23G 5/32 ZAB F23G 5/32 ZAB 5/44 ZAB 5/44 ZABB

Claims (2)

[Claims] 1. A refuse incinerator, a rotary sludge drying device provided with a dry sludge discharge port facing a combustion exhaust gas outlet of the waste incinerator, and a dry sludge opening to the combustion exhaust gas outlet or the incinerator. An input port, the dry sludge discharge port, and a dry sludge moving unit capable of transporting the dry sludge over the outside of the furnace, and the dry sludge moving unit discharges the dry sludge discharged from the dry sludge discharge port. Discharged to the outside of the furnace, or
A waste incinerator having a sludge drying device, wherein the dry sludge can be carried into the furnace of the waste incinerator through the combustion exhaust gas outlet or the dry sludge input port. 2. A flue gas outlet of the refuse incinerator is provided at least at two places, and a sludge drying device is provided on the first flue gas outlet side so that a dry sludge discharge port of the sludge drying device faces the second sludge drying device. The flue gas outlet side is connected to the flue gas outlet after the flue gas outlet discharged from the first flue gas outlet of the sludge drying device through the sludge drying device, or to the bypassed exhaust gas flue, and 2. A waste incinerator having a sludge drying device according to claim 1, characterized in that dampers are provided respectively at the two combustion exhaust gas outlets.