JPH0814521A - Vibrating screen for fluidized bed - Google Patents

Abstract

PURPOSE:To prevent an apparatus after a vibrating screen from being destroyed by thermal damage and to continuously operate a process for removing incombustible matter from fluidized sand in the screen for a fluidized bed to be applied to a waste incinerating fluidized-bed furnace, etc. CONSTITUTION:The vibrating screen for a fluidized bed comprises a screen body 2, a vibrator 3, a screen 4, and cooling means 5, wherein the means 5 for cooling fluidized sand A screened by the screen 4 is provided particularly in the body 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a vibrating sieve for a fluidized bed furnace which is applied to a waste incineration fluidized bed furnace for incinerating general municipal solid waste or industrial waste.

[0002]

2. Description of the Related Art Conventionally, as a fluidized bed furnace of this kind, there is known one shown in FIG. 3 which is described in, for example, Japanese Utility Model Publication No. 59-16645 and Japanese Utility Model Publication No. 2-16117. The fluidized bed furnace 50 includes a furnace main body 51 in which fluidized sand A to be a fluidized bed is stored, a feeder 52 for supplying waste B to the furnace main body 51,
Exhaust machine 53 for discharging fluidized sand A containing incombustible material C (metal, earth and sand, etc.) in furnace body 51, and vibration for sieving fluidized sand A containing incombustible material C from now on into incombustible material C and fluidized sand A Sieve 54
A bucket conveyor 55 for returning the fluidized sand A to the furnace body 51, a gas discharge duct 56 for discharging the gas burned in the furnace body 51, and an air for supplying air for flowing the fluidized sand A to the furnace body 51. It is composed of a supply pipe (not shown) and the like. The discharger 53 is a water-cooled screw feeder, and includes a casing 57 having a water jacket, a screw 58 rotatably provided on the casing 58, a speed reducer 59 for rotating the screw 58, and an electric motor 60.
And a water pump 61 for supplying cooling water to each water jacket. The vibrating screen 54 includes a screen body 62, a vibrator 63 that vibrates the screen body 62, a screen 64 that is provided in the screen body 62 and screens the fluidized sand A containing the incombustible material C into the incombustible material C and the fluidized sand A. Made of In such a fluidized bed furnace 50, the waste B containing the incombustible material C is supplied by the feeder 52.
Is supplied to the furnace main body 51 according to
Will be incinerated. After incineration, the remaining incombustibles C together with the fluidized sand A are discharged from the furnace main body 51 by the discharge machine 53 to the vibrating sieve 54.
It is sent while being gradually cooled. Incombustible C sent
The fluidized sand A containing the is classified into fluidized sand A and incombustible material C by the screen 64 of the vibrating sieve 54. The fluidized sand A that has been sieved is returned to the furnace body 51 by the bucket conveyor 55. As a result of the above, the fluidized bed in the furnace body 51 is always kept at a constant fluidized sand purity. The fluidized sand A is discharged from the discharge machine 53.
However, the inversion and stirring are not sufficient during the transportation by this, and the contact with the cooling surface does not reach the whole. And, the thermal conductivity of the fluidized sand A was also poor, and its cooling was not sufficient. Especially, when the waste B contains a large amount of incombustibles C, continuous operation must be performed, so the temperature of the fluidized sand A discharged from the discharger 53 rises considerably, and the equipment after the vibrating sieve 54 heats up. There was a problem of causing physical damage. That is, in the fluidized bed furnace 50 of this type, since the incombustible material C contained in the waste material B is accumulated in the fluidized sand A which is the combustion medium, the incombustible material C is extracted from the furnace body 51. Must be removed. However, since the fluidized sand A extracted from the furnace main body 51 is at a high temperature, the continuous operation is difficult, and there is a problem that thermal damage and heat loss of the transfer equipment become large.

[0003]

SUMMARY OF THE INVENTION The present invention was devised in order to solve this problem in view of the above problems, and its purpose is to prevent the equipment after the vibrating sieve from being thermally damaged. It is an object of the present invention to provide a vibrating screen for a fluidized bed furnace which is capable of preventing and continuously operating the process of removing incombustibles from fluidized sand.

[0004]

The vibrating screen for a fluidized bed furnace of the present invention basically comprises a screen body, a vibrating machine for vibrating the screen body, and a fluidized sand provided in the screen body and containing incombustibles. In a vibrating sieve for a fluidized bed furnace having a screen for sieving the non-combustible material and fluidized sand, a feature is that the sieve body is provided with a cooling means for cooling the fluidized sand screened by the screen. .

[0005]

When the vibrator is operated, the sieve body is vibrated.
The fluidized sand containing incombustibles is supplied into the sieve body and is screened into incombustibles and fluidized sand by a screen. The fluidized sand thus screened is cooled by a cooling means. At this time, the cooling means is vibrated together with the sieve body, so that the sieved fluidized sand is violently collided with and agitated to effectively cool the sand.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional side view showing an outline of a vibrating screen for a fluidized bed furnace according to an embodiment of the present invention. 2 is a cross-sectional plan view of FIG. The vibrating screen 1 is mainly composed of a screen body 2, a vibrator 3, a screen 4, and a cooling means 5, and is applied to a waste incineration fluidized bed furnace or the like. The screen body 2 is a basic part of the vibrating screen 1, and is long in the front-rear direction (left-right direction in FIG. 1) and elastically supported by the front and rear elastic bodies 6 with respect to the fixed side. Is an inlet 7 to which the fluidized sand A containing the incombustibles C is supplied, a first outlet 8 for discharging the incombustibles C screened by the screen 4 on the lower rear side, and a screen 4 on the front side thereof. The second outlets 9 for discharging the fluidized sand A sieved by are respectively provided. Inlet 7 of sieve body 2
Is connected to the outlet of the ejector 54, and the second outlet 9 is not shown in FIG.
It is connected to the entrance of 5. The vibrator 3 vibrates the screen body 2, and is provided in the lower middle of the screen body 2. The screen 4 is provided in the sieve body 2 and sieves the fluidized sand A containing the incombustible matter C into the incombustible matter C and the fluidized sand A. The screen 4 has a large number of through holes 10 with a predetermined mesh.
Is provided to divide the inside of the chamber into upper and lower chambers, and the incombustible material C is left on top of it, and the fluidized sand A is allowed to pass through and dropped below it. The cooling means 5 is provided in the sieve body 2 and cools the fluidized sand A that is sieved by the screen 4, and includes front and rear headers 11 located on the front and rear lower sides outside the sieve body 2. Connected to the front header 11 and a plurality of water pipes 12 which are interposed between the pipes and penetrate through the sieve body 2 and are located in the lower chamber and which are long in the front-rear direction and arranged at predetermined intervals in the left-right direction. Supply pipe 13, a discharge pipe 14 connected to the rear header 11, a flexible pipe 15 provided between the supply pipe 13 and the discharge pipe 14, and a cooling pipe connected to the supply pipe 13 to supply cooling water. And a cooling water pump 16.

Next, the operation will be described based on such a configuration. When the vibrator 3 is activated, the sieve body 2 is vibrated.
The fluidized sand A containing the incombustibles C from the discharger 53 is supplied from the inlet 7 into the sieve body 2, and the incombustibles C are fed by the screen 4.
And fluidized sand A are sieved. Incombustible C is screen 4
It moves upwards and is discharged backward from the first outlet 8.
The fluidized sand A passes through the through hole 10 of the screen 4 and drops below it, moves rearward and is discharged from the second outlet 9,
It is returned to the furnace main body 51 by the bucket conveyor 55. When the cooling water pump 16 of the cooling means 5 is operated, the cooling water flows through the supply pipe 13 → flexible pipe 15 → header 11 → water pipe 12 → header 11 → flexible pipe 15 → exhaust pipe 14, and the screen 4
The fluidized sand A dropped from is cooled by the cooling water flowing through the water pipe 12. At this time, since the water pipe 12 is vibrated together with the sieve body 2, the fluidized sand A dropped from the screen 4
Are violently collided with this, stirred, and cooled effectively. In particular, since there are a plurality of water pipes 12, the number of places in contact with the fluidized sand A increases, and the collision and stirring effects are remarkable. Since the flexible pipe 15 is provided in the middle of the supply pipe 13 and the discharge pipe 14, there is no problem even if the header 11 and the water pipe 12 vibrate together with the sieve body 2. Since only the sieved fluidized sand A is cooled, the cooling efficiency is improved as compared with the case where the fluidized sand A containing the incombustible material C is cooled. Since the fluidized sand A is made to collide with the water pipe 12 and agitated by utilizing the vibration of the vibrating sieve 1, the heat transmission efficiency of the fluidized sand A and the cooling water in the water pipe 12 is increased, and the limited vibrating sieve is used. Even with a small heat transfer area of the cooling means 5 in 1, the fluidized sand A is sufficiently cooled. That is, even if the cooling area of the cooling means 5 is small, the fluidized sand A can be efficiently cooled. Since the fluidized sand A is effectively cooled, it is possible to prevent thermal damage to the vibrating sieve 1 and subsequent devices, such as the bucket conveyor 55, and to continuously operate the process of removing the incombustible material C from the fluidized sand A. It will be possible. Since the water pipe 12 of the cooling means 5 is provided along the front-rear direction, the flow of the fluidized sand A is not hindered. The cooling water from which the heat is recovered from the discharge pipe 14 of the cooling means 5 can be used as water supply for a boiler and the like attached to the fluidized bed furnace 50.

Although the cooling means 5 is composed of the header 11, the water pipe 12, the water pump 16 and the like in the above embodiment, the cooling means 5 is not limited to this, and may be a jacket method such as a water cooling jacket method or the like. Although the number of the water pipes 12 of the cooling means 5 is plural in the previous embodiment, the number of the water pipes 12 is not limited to this and may be, for example, a single one.

[0009]

As described above, according to the present invention,
The following excellent effects can be achieved. (1) It is composed of a sieve body, a vibrator, a screen, and a cooling means. Especially, since the cooling means for cooling the fluidized sand screened by the screen is provided in the sieve body, the equipment after the vibrating sieve is protected from thermal damage. In addition to being able to prevent it, continuous operation of the process of removing incombustibles from fluidized sand becomes possible. (2) Since only the sieved fluidized sand is cooled by the cooling means, the cooling efficiency is improved accordingly. (3) Since the cooling means is provided in the sieve body to utilize this vibration, the fluidized sand that has been sieved collides with the cooling means and is agitated, so that the fluidized sand is generated even if the heat transfer area of the cooling means is small. Can be cooled effectively.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an outline of a vibrating screen for a fluidized bed furnace according to an embodiment of the present invention.

2 is a cross-sectional plan view of FIG.

FIG. 3 is a vertical sectional side view showing an outline of a conventional fluidized bed furnace equipped with a vibrating screen.

[Explanation of symbols]

1, 54 ... Vibrating sieve, 2, 62 ... Sieve main body, 3, 63 ... Vibrating machine, 4, 64 ... Screen, 5 ... Cooling means, 6 ... Elastic body, 7 ... Inlet, 8 ... First outlet, 9 ... Two outlets, 10 ... Through holes, 11 ... Header, 12 ... Water pipe, 13 ... Supply pipe, 14 ...
Discharge pipe, 15 ... Flexible pipe, 16 ... Cooling water pump, 50 ... Fluidized bed furnace, 51 ... Furnace body, 52 ... Feeder, 53 ... Discharger,
55 ... Bucket conveyor, 56 ... Gas exhaust duct, 57
… Casing, 58… Screw, 59… Reducer, 60…
Electric motor, 61 ... water pump, A ... fluid sand, B ... waste, C
…Incombustible.

Claims (1)

[Claims] 1. A vibration for a fluidized bed furnace comprising: a screen body; a vibrator for vibrating the screen body; and a screen provided on the screen body for screening fluid sand containing incombustible material into incombustible material and fluid sand. A vibrating screen for a fluidized bed furnace, wherein the screen body is provided with a cooling means for cooling the fluidized sand screened by a screen.