JPH0346724B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an incineration residue processing device for melting incineration residue discharged from an incinerator, and in particular, a slit-shaped molten slag discharge port is provided in the hearth to sequentially discharge the molten slag. An incineration residue treatment device that discharges and separates it from unmelted ash, thereby reducing the ventilation resistance of the residue moving bed and improving combustion efficiency, as well as preventing clogging of the furnace due to crosslinking and ensuring stable operation. Regarding.

Generally, municipal garbage, industrial waste, etc. are incinerated, but the incineration residue that is discharged is usually disposed of in a landfill.

Incidentally, this landfill disposal poses larger social problems than issues such as securing a landfill site and measures for inundation activation.

Therefore, recently, a method for melting incineration residue has been developed which solves these problems all at once and makes it non-polluting.

This processing method will be explained based on Fig. 1.
Reference numeral 1 denotes an incinerator such as a stoker type furnace or a rotary kiln type furnace, in which waste M such as municipal garbage is incinerated with combustion air 2. The discharged incineration residue N is introduced into the melting furnace 4 of the incineration residue treatment device 3, and the unburned carbon remaining therein is combusted by the combustion air 5 supplied at the inlet of the melting furnace, and the combustion heat is used to burn it. Heat and melt the incineration ash. The molten slag 6 flows diagonally downward through the hearth 7 and forms a predetermined-shaped lump from the discharge end 8 and falls into a slag cooling water tank 9 located below, where it is cooled and solidified into lump-like solids. will be generated.

However, in this type of conventional example, although combustion air is supplied into the residue layer, the molten slag flows along the hearth with unmelted ash, increasing ventilation resistance and reducing combustion efficiency and There were cases in which the melting efficiency decreased and a large amount of unmelted ash was discharged, making it impossible to perform a sufficient melting process.

Furthermore, if the slag and unmelted ash flow together, the molten slag tends to adhere to the hearth and the furnace walls and harden, forming a bridge, which may cause a clogging problem in the furnace.

In addition to the above-mentioned conventional example, an oil burner is also used to directly irradiate this flame onto the surface layer of the residue to melt it, but the same problems as above occur in this case as well. In order to prevent this, it is necessary to melt the unmelted ash using a secondary burner or to remelt the slag that has adhered and solidified to the furnace wall, resulting in increased oil consumption.

The present invention has focused on the above-mentioned problems and has been devised to effectively solve the problems.

An object of the present invention is to form a number of slit-shaped molten slag discharge ports in a hearth provided at the bottom of a melting furnace to actively separate and discharge molten slag from a moving bed. It is an object of the present invention to provide a combustion residue processing device which can reduce the ventilation resistance of the remaining moving bed to improve combustion efficiency, and can prevent clogging of the furnace due to crosslinking and perform stable operation.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

First, FIG. 2 is a longitudinal sectional view showing a preferred embodiment of the present invention, and FIG. 3 is an enlarged perspective view of section A in FIG.

As shown in the figure, the incineration residue processing equipment
It has a melting furnace 11 for forming a moving layer 10. This melting furnace 11 has a substantially cylindrical casing 12 whose outer shell is made of refractory bricks or the like.
A hopper, that is, an incineration residue inlet 13 is formed at one end of the upper part and is expanded upward to be connected to the residue outlet of the incinerator 1. The casing 12 is inclined downwardly at an appropriate angle along the direction of transfer of the transfer layer 10 transferred therein, thereby facilitating transfer of the transfer layer 10. A pusher 14 connected to a cylinder mechanism or the like is mounted on one side wall of the casing 12 in the upper direction of the inclination.
is provided so as to be movable back and forth along the longitudinal direction of the casing, that is, along the transport direction of the moving layer 10, and is configured such that the moving speed of the moving layer 10 can be controlled by changing the operating speed and the like.

Further, an unmelted ash discharge port 15 is formed at the lower end of the casing 12 in the inclined direction, and this discharge port 1
5 is connected to an unmelted ash discharge passage 16 extending vertically to discharge the remaining unmelted ash, and solid unmelted ash falling through this passage is cooled. It can be cooled in a water tank (see Figure 1).

Further, the casing side wall or the furnace side wall 17,
Combustion air supply means 18 for supplying combustion air into the moving bed is provided above the center in the longitudinal direction. This supply means 18 consists of combustion air blowing ports 19 that are opposed to the furnace side wall and are bored at predetermined intervals along the inclination direction of the furnace side wall, and an on-off valve 20 is interposed in the middle of the combustion air blowing holes. The combustion air supply pipe 21 is connected to a combustion air supply pipe 21, and high-temperature heated air is blown into the moving bed from the side of the moving bed so as to cross the inside of the casing in the width direction. The opening degree of each on-off valve 20 is individually controlled by a combustion air controller (not shown), so that the required amount of air can be supplied to the moving bed.

A hearth 22 and a molten slag discharge port 23, which are the features of the present invention, are formed in the melting furnace 11 configured as described above.

This hearth 22 is for transferring the moving layer 10 in the discharge direction while melting it. Specifically, this hearth 22 is formed by molding heat-resistant ceramics into a rectangular shape. Consisting of a large number of grate plates 24, the longitudinal direction of these grate plates 24 are positioned in the width direction of the casing 12, and are spanned between both side walls of the casing 12, and are arranged facing each other at a predetermined gap in the inclination direction of the casing. A hearth 22 is constructed by attaching them adjacently.

Note that no gap is formed in the hearth located below the incineration residue inlet 13 of the casing, since the residue is not yet melted or even if it is melted, the amount of melted residue is small.

A large number of slit-shaped gaps 25 formed between the grate plates form the molten slag discharge port 23.
Constructed as.

Therefore, this molten slag discharge port 23 is connected to the hearth 22
In particular, this discharge slit needs to have the function of allowing only the molten slag 26 in the moving bed to fall and separating the unmelted ash remaining on the hearth. The width l of the gap should be long enough to prevent unmelted ash from falling.

In the illustrated example, the grate plate 2 is formed into a rectangular shape.
Although the molten slag discharge ports 23 are formed in the hearth 22 in a lattice shape by placing the molten slag discharge ports 23 adjacent to each other with a predetermined gap between them, the present invention is not limited thereto. It may be formed into a mold and have molten slag discharge ports bored therein in a grid pattern.

A heating means 27 is provided at the bottom of each grate plate 24 for heating the moving layer 10 flowing down the upper surface thereof. This heating means 27 is
A large number of heating elements 28 are arranged along the longitudinal direction at the bottom of the rectangular grate plate 24, and a semi-circular cross-section is provided at a predetermined interval from the heating elements 28 so as to cover each heating element. It is configured with a heating element protection case 29. Since this heating element 28 is required to output at a high temperature, it is made of, for example, silicon carbide molded into a rod shape, and by passing an electric current through it through the wiring 30, it is possible to use a metal heating element (such as a nichrome wire). This results in a higher temperature than can be achieved, and the moving layer 10 on the grate plate 24 is heated. Although the wiring 30 is connected to a temperature controller (not shown) and its temperature is controlled, a plurality of wirings may be used to control the temperature of each heating element in accordance with the position where each heating element is installed.

In order to prevent the heating element 28 inside the case from deteriorating, it is preferable to make the inside of the case a sealed structure and fill it with an inert gas such as nitrogen.

A funnel-shaped molten slag discharge passage 32 whose diameter is reduced downward is provided below the molten slag discharge port 23, passing through the casing bottom wall 31, and the molten slag 26 falling into this passage 32 is provided.
The slag can be introduced into a slag cooling water tank (not shown) to be cooled and solidified. Further, a flue 33 is branched in the middle of the passage, similar to the unmelted ash discharge passage 16, and is configured so that combustion exhaust gas can be sucked and discharged by a blower (not shown).

The operation of the present invention configured as above will be described.

First, as shown in Figures 1 and 2, industrial waste M such as municipal waste is fed into the incinerator 1 from the input port, and after being burned normally therein, the generated incineration residue is transferred to the incinerator 1. Melting furnace 11 connected to the end of 1
is supplied into the incineration residue inlet 13 of the incineration residue. During combustion in this incinerator 1, unburned carbon in the residue is 7
Combustion is controlled to remain within ~25%, preferably 10-20%.

Specifically, combustion control is performed by adjusting the input amount of waste, the amount of combustion air, the stoker feed speed in the case of a stoker type, and the rotation speed in the case of a rotary kiln type.

As shown in FIGS. 2 and 3, the incineration residue N containing unburned carbon is stacked on the hearth 22 in the melting furnace 11, and this stacked residue is pushed by the pusher 14 and becomes the moving layer 10. Flows down in the direction of inclination or discharge.

On the other hand, this moving bed 10 is sequentially heated by the heating element 28 of the heating means 27 provided at the lower part of the hearth, and at the same time, the unburned carbon contained therein is removed by the combustion air supplied from the combustion air blowing port 19. The incinerated ash will be melted by the combustion heat generated at this time.

The generated molten slag flows down the hearth 22 and is immediately discharged from the corresponding molten slag discharge port 23 in the direction of gravity, and is separated from the moving bed 10 .
Therefore, only the unmelted ash that has not yet been melted remains in the moving bed and is transferred. Further, as this unmelted ash flows further down, it will be sequentially melted, but at the same time as it becomes molten slag, it will be immediately discharged through the molten slag discharge port 23 in the direction of gravity as described above. .

Therefore, only the unmelted ash can be separated and transported over the hearth without the molten slag and unmelted ash flowing together, reducing the ventilation resistance in the moving bed and allowing combustion of this unmelted ash. Good contact with the air for use can be made, and this combustion and melting can be promoted.

Further, since the molten slag generated as described above is immediately discharged, it does not adhere to and harden on the hearth 22 or the furnace wall, thereby preventing the occurrence of bridging or the like.

Incidentally, since heat is constantly supplied from the lower part of the hearth 22 toward the moving bed 10 by the heating means 27, the occurrence of crosslinking of the molten slag described above can be almost certainly prevented.

After the separated molten slag 26 falls through the molten slag discharge passage 32, it is cooled and solidified in the slag cooling water tank (see FIG. 1).

The unmelted ash 34 that finally remains, that is, unmelted materials, is discharged from the unmelted ash discharge port 15, falls through the unmelted ash discharge passage 16, and is cooled and solidified in the cooling water tank.

Then, when the molten slag 26 and the unmelted ash 34 fall, the combustion exhaust gas is sent to the blower 3 in the same direction.
5 to prevent cooling of the molten slag outlet 23 and the unmelted ash outlet 15, and the flue 33,
It will be discharged from 33.

In this way, since the generated molten slag is immediately and actively separated from the moving bed 10,
It can prevent molten slag from adhering to the furnace walls, etc.
Moreover, at the same time, the ventilation resistance of the moving bed 10 decreases, and the contact between the unmelted ash and the combustion air becomes good, so that the combustion and melting can be promoted.

In addition, since the combustion air supply means 18 supplies air from the side of the moving bed 10 in parallel and directly into the moving bed, combustion can be performed from inside the residue, and there is little heat radiation. can be retained in the layer and effectively contribute to melting.

In the above embodiment, the moving bed is heated from the lower part of the hearth with the heating element 28, but the present invention is not limited to this, and heating with the heating element may be performed through the furnace wall such as the side or upper part, or Alternatively, it may be inserted into a protective case and installed in the furnace.

In summary, according to the present invention, the following excellent effects can be achieved.

(1) By actively discharging molten slag from the moving bed and preventing its wake, the ventilation resistance in the moving bed can be reduced and the combustion and melting of unmelted ash can be promoted.

(2) Separating and discharging the molten slag prevents it from adhering to the furnace walls and solidifying, thereby preventing the occurrence of crosslinking.Therefore, the furnace is free from clogging problems and stable operation is possible.

(3) Furthermore, since combustion efficiency can be promoted, auxiliary fuel etc. are not required, and running costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing a conventional incineration residue processing device connected to an incinerator, FIG. 2 is a vertical cross-sectional view showing a preferred embodiment of the present invention, and FIG. 3 is a section A in FIG. It is an enlarged perspective view. In the figure, 1 is an incinerator, 10 is a moving bed, 11 is a melting furnace, 22 is a hearth, and 23 is a molten slag discharge port.
26 is molten slag, 34 is unmelted ash, and N is incineration residue.

Claims (1)

[Claims] 1. In an incineration residue treatment device that burns the unburned carbon contained in incineration residue discharged from an incinerator and obtains it as molten slag, a moving layer of incineration residue is formed in order to melt and process the above-mentioned incineration residue discharged. a hearth provided in the melting furnace for melting the moving layer and transporting it in a discharge direction; An incineration residue processing device characterized by comprising a molten slag discharge port for separating molten slag from unmelted ash.