JPS62280512A - Fluidized bed incinerator - Google Patents

Abstract

PURPOSE:To simplify the configuration of a furnace as well as the structures of steel frames and furnace construction and reduce cost as well as repairing charge by a method wherein the titled incinerator is provided with an unburnt matter discharging chute, arranged at the central part of a furnace floor, and a slanted reflection body, guiding fluidizing medium from the central part of the furnace toward the upper part of a fluidized bed, while a fluidizing air for the central part of the furnace is sent more than the outer side of the furnace. CONSTITUTION:An unburnt matter discharging chute 6 is provided at the central part of a furnace floor 8 and a reflection body 21, provided with upper and lower slanted surfaces 21a, 21b and a rohmblc section, is provided in the central part of a furnace 1 above a fluidized bed. The much amount of fluidizing air 7b is fed from the central part of the furnace while the smaller amount of fluidizing air 7a is fed from the outer side of the furnace. incinerating matters from the top 2 of the furnace are scattered outwardly from the central part along the upper surface 21a of a slanted reflection body 21. Whirling flow 12 is generated in a sand layer 5 by the effects of the much amount of fluidizing air 7b from the central part of the reflection body 21,and the smaller amount of fluidizing air 7a from the outer side of the furnace and the lower slanted surface 21b from the central part of the reflection body 21 toward upper outside whereby the thrown incinerated matters 4 are scattered uniformly onto the sand layer 5, local combustion is prevented and unburnt matters 9, piled on the furnace floor 8, may be moved easily to an unburnt matter discharging chute 6.

Description

[Detailed description of the invention] 3. Detailed description of the invention [Industrial application field] This invention relates to a fluidized bed incinerator.

[Prior Art] An example of a general fluidized bed incinerator is shown in FIG. The materials to be incinerated 4 are charged into the fluidized bed incinerator 1 mainly through the furnace top input port 2 or the furnace side wall input port 3. The input incineration material 4 is
The fluidized air 7 reaches the fluidized sand layer 5 flowing above the hearth 8 and is incinerated. Noncombustibles 9 in the incombustible material are discharged from the noncombustibles discharge chute 6 along with the fluid medium.

In a fluidized bed incinerator, when incineration material 4 having a high mixing effect and heat transfer efficiency and a fast combustion rate is input, combustion is often completed before the incineration material 4 is dispersed throughout the sand layer 5. Become. As a result, combustion is active in the vicinity where the incineration material 4 is introduced, and the temperature of the sand layer 5 becomes high, but in a place away from there, almost no combustion occurs and the temperature of the sand layer is low. Such temperature differences cannot be resolved no matter how strong the mixing effect is, and not only will the incinerator not be able to demonstrate its incineration capacity, but the locally increased heat load may cause damage to refractories, etc. There is.

Furthermore, since the non-combustible material 9 has a density greater than the bulk density of the fluidized bed portion, it accumulates on the hearth 8 (dispersion plate). The accumulated incombustible materials 9 cannot be smoothly moved to the chute 6 due to the movement of the sand layer 5. As a result, a large amount of noncombustible material 9 accumulated on the hearth 8 prevents υ fluidization, and in the worst case, the furnace is shut down, the sand that is the fluidizing medium 5 is extracted, and the noncombustible material 9 is removed manually. I will have to.

Therefore, an incinerator shown in FIGS. 6 and 7 has been proposed in which a swirling flow is generated in the sand, which is the fluidized medium 5, on the hearth 8. In this structure, a reflective wall 11 is formed near the surface layer of the fluidized bed, which is substantially parallel to the hearth 8 with a downward slope toward the incombustible material discharge chute 6, and directs the fluidizing air into a large flow rate 7b, a small flow rate 7& By feeding a large flow of fluidized air from the vicinity of the discharge chute 6, a swirling flow shown by an arrow 12 is generated in the fluidized bed.

Due to this swirling flow 12, the incinerated material 4 is uniformly dispersed in the sand layer 5, and combustion is not partially completed. Furthermore, the non-combustibles move above the hearth 8 by the swirling flow 12 and smoothly move to the non-combustibles discharge chute 6.

[Problems to be Solved by the Invention] However, in this method, a reflecting wall is formed toward the inside of the furnace, so the shape of the furnace becomes complicated. Therefore, there are problems in that the steel frame structure and furnace construction structure are complicated, which is disadvantageous for incinerators that operate at high temperatures, and the cost is also high.

The object of the present invention is to provide a fluidized bed incinerator that can solve the above-mentioned problems.

[Means for solving the problem 2 effects] A non-combustible material discharge chute is provided at the center of the hearth, and an inclined reflector is provided at the top of the fluidized bed to guide the fluidized medium from the center of the furnace to the outside and upward. Make the air volume υ more than that in the outer part.

A simple configuration in which the inclined reflector is located in the center of the furnace allows
A swirling flow can be generated in the fluidized bed.

[Example] An embodiment of this invention will be explained with reference to FIGS. 1 and 2.

A non-combustible material discharge sheet is provided in the center of the hearth 8. In the center of the furnace 1, there is a vertically inclined surface 21 above the fluidized bed.
A reflector 21 having a diamond-shaped cross section is provided. A large amount of fluidized air 7b is fed from the center of the furnace, and a smaller amount of fluidized air 7a is fed from the outside.

Therefore, the incineration material 4 introduced from the top of the furnace is transferred to the inclined reflector 2.
1, distributed outward from the center. On the other hand, on the sand layer 5, due to the action of the large flow of fluidized air 7b from the center of the reflector 21, the small flow of fluidized air 7a at the outer side, and the lower slope 21b directed outward and upward from the center of the reflector 21, A swirling flow 12 is generated. This swirling flow 12 is
To uniformly disperse the thrown incineration materials 4 in a sand layer 5 to prevent partial combustion, and also to easily move incombustible materials 9 accumulated on a hearth 8 to a noncombustible material discharge chute 6. This prevents the incombustibles 9 from accumulating on the hearth 8. Thereby, damage to the refractory due to local heat load can be prevented, and fluidization can be prevented from being inhibited by the influence of the incombustible material 9.

A feature of the present invention is that the shape of the furnace body 1 is very simple. This simplifies the steel structure and furnace construction, which is advantageous in terms of cost.

Furthermore, since the reflector 21 can be installed independently from the main structure of the furnace body 1, the permissible width of the mounting position is wide and the position can be easily changed.

Furthermore, since this reflector is exposed to high temperatures, it is desirable to cool the inside with air, water, or the like. It goes without saying that wear-resistant materials should be used in the areas where the sand layers come into contact. - in the figure is an example of air cooling/mother eve.

Next, another embodiment will be explained with reference to FIGS. 3 and 4. This has a configuration in which a pair of plate-shaped reflectors 31, 31 are placed at an upper position of the fluidized bed, spaced apart from each other, and directed outward and upward from the center. As a result, the swirling flow 12 can be generated similarly to the first embodiment described above. Also, non-combustible materials 9
Since the incombustible materials 9 can be selectively dropped directly into the discharge chute 6, no accumulation of incombustible materials 9 on the hearth 8 occurs.

[Effects of the Invention] The fluidized bed incinerator of the present invention is as described above, and has the following effects.

(1) By locating the reflector at the center of the furnace, the furnace shape becomes simple. It is possible to improve the mixing and incineration of incinerated materials by swirling flow as before.

(2) Since the furnace shape is simple, the steel frame and furnace construction structure are simplified, reducing initial costs and repair costs.

(3) Depending on the shape of the reflector, it is possible to improve the dispersion performance of incinerated materials and the performance of discharging incombustible materials.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention, FIG. 2 is a view taken along the ■-■ arrow in FIG. 1, and FIG. 3 is a longitudinal sectional view of another embodiment.
Figure 4 is a view from the IV-11/arrow in Figure 3, Figure 5 is a vertical cross-sectional view of a conventional fluidized bed incinerator, and Figures 6 and 7 are vertical cross-sectional views of different swirling fluidized bed incinerators. It is. 5...Fluidized medium (sand), 6...Incombustible material discharge chute, 7m, 7b...Fluidized air, 8... Hearth (dispersion plate), 12... Swirling flow, 21.31 ...Slanted reflector. Figure 2 Figure 4 Figure 5 Figure 7 Figure 6 K

Claims (1)

[Claims] A non-combustible matter discharge chute is installed in the center of the hearth, and an inclined reflector is installed above the fluidized bed to guide the fluidized medium from the center of the furnace to the outside and upward, thereby increasing the amount of fluidized air in the center of the furnace than in the outside. A fluidized bed incinerator featuring: