JPH0730892B2 - Ceiling structure of waste melting furnace - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a ceiling structure of a surface melting type waste melting furnace for melting sewage sludge, municipal waste incineration ash, etc. generated in a sewage treatment plant as a melted product. .

2. Description of the Related Art A conventional surface melting type waste melting furnace is shown in FIG.
It is as shown in FIG. In FIGS. 3 to 4, the furnace outer cylinder 1 has a cylindrical shape and the inner peripheral surface is a refractory or is covered with an outer cylinder caster 2. The bottom of the furnace outer cylinder 1 has a slag port. 3 is open. Further, a furnace ceiling body 4 is vertically movably arranged inside the furnace outer cylinder body 1, and the furnace ceiling body 4 has a cylindrical shape and an outer peripheral surface thereof is covered with a ceiling caster 5 which is a refractory material. . Further, a charging port 6 is provided between the furnace outer cylinder 1 and the furnace ceiling body 4, and the waste that is the molten processed product charged into the furnace outer cylinder 1 from the charging port 6 is a waste. 7 stays around and below the ceiling casters 5 of the furnace ceiling body 4. Further, the waste material 7 that accumulates in the lower portion of the furnace ceiling body 4 forms a mortar-shaped inclined surface from the peripheral edge of the furnace ceiling body 4 toward the opening edge of the slag port 3,
The furnace ceiling body 4 is positioned at an appropriate height so that the angle formed by this inclined surface and the bottom surface of the furnace outer cylinder 1 becomes the repose angle of the waste 7.

The ceiling portion 8 forming the bottom portion of the furnace ceiling body 4 is formed in a two-layer structure by the ceiling caster 5 provided on the lower surface of the top plate 9 and the cooling jacket 10 provided on the upper surface of the top plate 9. The ceiling casters 5 are supported by anchor bricks 11 provided on a top plate 9. Further, a space between the lower surface of the ceiling caster 5 of the ceiling portion 8 and the inclined surface of the waste 7 is formed in the combustion chamber 12, and the ceiling portion 8 is provided with a combustion device 13 for injecting flame toward the combustion chamber 12. It is provided.

The surface of the waste 7 forming the combustion chamber 12 is melted by using the combustion heat of the flame of the combustion device 13 and the sludge itself as a heat source for melting, and the melted waste 7 is continuously melted as slag from the slag port 3. Run down. Further, when the level of the melting surface A of the waste material 7 decreases as the melting progresses, the unmelted waste material 7 sequentially drops from the vicinity of the peripheral edge of the furnace ceiling body 4 as the outer tube body 1 rotates. Then, the unmelted waste 7 is replenished on the melting surface A. Then, the ceiling caster 5 of the ceiling portion 8 forming the combustion chamber 12 is cooled by the cooling water B flowing inside the cooling jacket 10. In addition, the outer cylinder casters 2 of the furnace outer cylinder body 1 are hardly affected by the combustion heat because the waste material 7 retained between the outer cylinder casters 2 and the combustion chamber 12 acts as a heat insulating material.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-described configuration, the lower surface side of the ceiling caster 5 facing the combustion chamber 12 has a high temperature of 1200 to 1300 ° C, which is close to the melting temperature (1300 to 1400 ° C), while cooling. Jacket
The upper surface side of the ceiling caster 5 which contacts 10 becomes a low temperature of 50 to 100 ° C. Therefore, there is a problem that the temperature gradient in the thickness direction of the ceiling casters 5 becomes large, and the ceiling casters 5 are damaged or fall off due to strain such as thermal contraction. Further, the anchor brick 11 is formed of a denser material than the ceiling caster 5 because it requires strength, and the thermal conductivity is higher than that of the ceiling caster 5 because of the dense material. For this reason, the anchor bricks 11 are more susceptible to the strain of heat shrinkage than the ceiling casters 5, and the anchor bricks 11 are often damaged first, and the ceiling casters 5 that have lost the support material often fall off subsequently.

The present invention solves the above problems, and an object of the present invention is to provide a ceiling structure of a waste melting furnace that can reduce the influence of heat contraction on the ceiling casters 5 and prolong the life of the ceiling casters.

Means for Solving the Problems In order to solve the above problems, the present invention provides a ceiling surface of a combustion chamber formed by a ceiling caster provided on a lower surface side of a ceiling portion, and an inner peripheral surface of the combustion chamber is a molten processed material. In the waste melting furnace to be formed, a cooling jacket through which cooling air flows is provided on the upper surface side of the ceiling part, and a cooling water jacket through which cooling water flows is provided between the cooling jacket and the ceiling caster. A plurality of cooling air vents communicating with the cooling jacket and the other end communicating with the combustion chamber are provided so as to penetrate the cooling water jacket and the ceiling caster in the thickness direction.

With the above configuration, the ceiling caster receives the heat of combustion in the combustion chamber, the lower surface side is heated, and the upper surface side is cooled by the cooling water flowing inside the cooling water jacket.
It receives a cooling action from the upper surface side to the lower surface side. further,
The inside of the ceiling caster is cooled from the periphery of the cooling air ventilation hole by the cooling air flowing from the cooling jacket through the cooling air ventilation hole into the combustion chamber. For this reason, the temperature gradient in the thickness direction of the ceiling casters becomes gentle, and the heat conduction of the ceiling casters is divided in the plane direction by the cooling in the cooling air ventilation holes, so that a limited area is sandwiched between the cooling ventilation holes. Heat shrinkage strain will occur on the ceiling casters, and the ceiling casters will not be damaged significantly at a time.

Further, the cooling air is heated as the ceiling casters are cooled and is used as combustion air in the combustion chamber. At this time, the cooling air is blown out from the respective cooling vents over the entire surface of the ceiling caster, so that the diffusion effect of the air in the combustion chamber is increased and the combustion efficiency is improved.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. First
The figure shows the ceiling of the waste melting furnace. In FIG. 1, the ceiling part 21 forms a ceiling surface of the combustion chamber 23 by a ceiling caster 22 made of refractory provided on the lower surface side, and the ceiling caster 22 is supported by an anchor brick 25 provided on a ceiling plate 24. ing. In addition, the inner peripheral surface of the combustion chamber 23 is a molten processed material such as waste.
Formed in 26. A cooling jacket 27 is provided on the upper surface side of the ceiling portion 21, and cooling air 28 is supplied to the inside of the cooling jacket 27. Cooling jacket 27
A cooling water jacket 30 to which cooling water 29 is supplied is provided on the top surface of the top plate 24 between the ceiling caster 22 and the ceiling caster 22. Then, a plurality of cooling air ventilation holes 31 are formed through the cooling water jacket 30 and the ceiling casters 22 in the thickness direction,
One end of the cooling air vent hole 31 communicates with the cooling jacket 27 and the other end communicates with the combustion chamber 23.

The operation of the above configuration will be described below. The ceiling caster 22 receives the heat of combustion in the combustion chamber 23 and is heated on the surface side, and the upper surface side is effectively cooled by the cooling water 29 flowing inside the cooling water jacket 30, and from the upper surface side to the lower surface side. Receives cooling action. In addition, ceiling casters
The inside of the cooling air 22 is cooled from around the cooling air ventilation hole 31 by the cooling air 28 flowing from the cooling jacket 27 into the combustion chamber 23 through the cooling air ventilation hole 31. For this reason, the ceiling casters 22
The temperature gradient in the thickness direction becomes gentle, and the heat conduction of the ceiling caster 22 is divided in the surface direction by the cooling in the cooling air ventilation hole 31, so that the cooling ventilation hole 31
The heat shrinkage strain is generated in each of the limited areas sandwiched between the ceiling caster 22 and the ceiling caster 22 and the ceiling caster 22 is not significantly damaged at a time.

The cooling air 28 is heated as the ceiling casters 22 are cooled, and is used as combustion air in the combustion chamber 23. At this time, the cooling air 28 flows from the cooling air vents 31 to the ceiling casters 22.
Since the air is jetted out over the entire surface, the diffusion effect of the air in the combustion chamber 23 is increased, and the combustion efficiency is improved.

As described above, according to the present invention, the inside of the ceiling caster is cooled from around the cooling air ventilation hole by the cooling air flowing from the cooling jacket through the cooling air ventilation hole into the combustion chamber. Cooling in the air vents allows the heat transfer of the ceiling casters to be divided in the plane direction, and distortion of heat contraction occurs in each of the limited areas sandwiched between the cooling air vents, so the ceiling casters are greatly damaged at one time. Can be prevented.

Further, since the cooling air is jetted from the respective cooling ventilation holes over the entire surface of the ceiling caster, the combustion efficiency can be improved by the diffusion of the air in the combustion chamber.

[Brief description of drawings]

FIG. 1 is a sectional view of a ceiling portion showing an embodiment of the present invention, FIG.
FIG. 1 is an overall configuration diagram of a conventional waste melting furnace, and FIG. 3 is a sectional view of a conventional ceiling portion. 21 …… Ceiling part, 22 …… Ceiling caster, 23 …… Combustion chamber, 26
…… Melted product, 27 …… Cooling jacket, 28 …… Cooling air, 29 …… Cooling water, 30 …… Cooling water jacket, 31 …… Cooling air vent.

Front page continuation (72) Takashi Nagayama, Takashi Nagayama 1-247 Shikitsu Higashi, Naniwa-ku, Osaka City, Kubota Iron Works Co., Ltd. (56) References 60-16837 (JP, Y2)

Claims (1)

[Claims] 1. A cooling air flow in a waste melting furnace in which the ceiling surface of a combustion chamber is formed by a ceiling caster provided on the lower surface side of the ceiling portion, and the inner peripheral surface of the combustion chamber is formed of a molten processed material. A cooling jacket is provided on the upper surface side of the ceiling part, and is provided between the cooling jacket and the ceiling casters to provide a cooling water jacket through which cooling water flows. One end communicates with the cooling jacket and the other end communicates with the combustion chamber. A ceiling structure of a waste melting furnace, wherein a plurality of cooling air vents communicating with the cooling water jacket and the ceiling casters are provided so as to penetrate in the thickness direction.