JPH0378523B2 - - 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, it is capable of controlling the supply of incineration residue and the amount of combustion and melting, and The present invention relates to an incineration residue processing device that can prevent clogging and perform stable operation.

Generally, municipal waste, 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 entrance of the melting furnace, and the combustion heat is used to burn it. Heat and melt the incineration ash. This molten slag 6
The slag flows diagonally downward through the hearth 7 and from the discharge end 8 into lumps of a predetermined shape and falls one after another into the slag cooling water tank 9 located below, where it is cooled and a lump-like solid is produced. It turns out.

By the way, in order to improve combustion efficiency, it is necessary to appropriately control combustion and melting amount.
In this type of conventional example, the structure is such that the residue or molten slag flows down the inclined hearth 7 due to its own weight, which not only makes it difficult to control the appropriate combustion and melting amount. In some cases, molten slag adheres to the furnace walls and solidifies, forming bridges and causing clogging problems.

Furnaces that are equipped with an ash pushing mechanism are also known, but this operation is only for the purpose of discharging the ash and does not control the amount of combustion and melting. Furthermore, in the conventional example, since the combustion air 5 is supplied at the inlet of the melting furnace to burn unburned carbon, a sufficient amount of heat is not supplied to the molten slag 6 flowing through the hearth 7, and the above-mentioned There was a problem of promoting the formation of crosslinks.

For this reason, attempts have been made to increase the combustion temperature and prevent the solidification of molten slag by supplying oxygen instead of air, but in this case, the power consumption of the oxygen generator is large, and the handling It wasn't easy either.

On the other hand, in addition to the above examples, on the surface of the burning residue,
It is also possible to melt the incineration residue or molten slag by directly irradiating it with flame from an oil burner, or to insert an electrode into the incineration residue or molten slag and melt it using Joule heat; Since the molten high-temperature part is exposed, there is a large heat loss due to radiant heat, and furthermore, since the thermal conductivity of the molten slag is poor, the amount of oil consumed inevitably increases, leading to an increase in running costs. In addition, the method using Joule heat cannot use unburned carbon in the residue as fuel, resulting in increased power consumption and is not suitable for practical use.

The present invention has been devised to effectively solve the above-mentioned problems, particularly focusing on the difficulty in controlling the amount of combustion and melting.

The object of the present invention is to provide a melting furnace having a hearth through which the discharged incineration residue flows down to form a moving layer, and a combustion air supply means having an air blowing port opened into the moving layer of the incineration residue. and a moving bed transfer means for changing the moving speed of the moving bed of the incineration residue transferred to the melting furnace, and a means for supplying combustion air into the moving bed to burn unburned carbon contained in the incineration residue. The incineration residue is combusted from the inside, and all the incineration residue is melted and processed, and the amount of transfer is varied by changing the operating interval, operating speed, etc. of the moving bed transfer means, and the combustion is carried out. ,
It is an object of the present invention to provide an incineration residue processing device that can control the amount of melting and prevent clogging of a furnace due to crosslinking.

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 first 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 its upper part and is expanded upward to be connected to the residue outlet of the incinerator 1 (see FIG. 1). The casing 12 is tilted downward at an appropriate angle along the direction of transport of the incineration residue or molten slag to be transported into the casing 12, thereby facilitating the transport of the moving bed 10 as will be described later.
A grate plate 15 is attached to the bottom of the casing 12 at a predetermined distance above the casing bottom wall 14 and along the inclination direction of the furnace, forming a hearth 16. The grate plate 15 is made of heat-resistant ceramics, for example, and is molded into a flat plate shape to improve the flow of molten slag and the like.

A heating means 1 is provided at the bottom of the grate plate 15 for heating the moving layer 10 flowing down the upper surface.
7 is provided, and a combustion air supply means 19 for supplying combustion air into the moving bed is provided on the casing side wall or the furnace side wall 18.

The heating means 17 includes a large number of heating elements 20, which are positioned in the lower part of the grate plate 15 in the width direction and arranged at predetermined intervals along the longitudinal direction of the grate plate, and a plurality of heating elements 20 arranged at predetermined intervals from each heating element 20. The heating element protection case 21 has a semicircular cross section and is separated from the heat generating element and covers the heating element protection case 21. Since the heating element 20 is required to output at a high temperature, it is made of, for example, silicon carbide molded into a rod shape, and a metal heating element (such as a nichrome wire) is formed by passing a current through the wire 45.
This results in a high temperature that cannot be obtained in the conventional method, and the moving layer 10 on the grate plate is heated. Although the wiring 45 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 portion where each heating element is located.

In order to prevent the heating element 20 inside the case from deteriorating, it is preferable that the inside of the case be a closed space structure and filled with an inert gas such as nitrogen.

Further, the combustion air supply means 19 includes combustion air blowing ports 22 which are opposed to the furnace side wall and are bored at predetermined intervals along the inclination direction thereof, and an on-off valve 23 is interposed in the middle. The combustion air supply pipe 24 is connected to each of these blowing ports, and high-temperature heated air is blown into the moving bed from the side thereof so as to cross the hearth 16. The opening degree of each on-off valve 23 is individually controlled by a combustion air controller (not shown), so that the required amount of air can be supplied into the moving bed.

Further, a slag discharge port 25 for discharging slag melted in the furnace is formed at the lower end of the casing 12 in the inclined direction, and a molten slag discharge passage 26 extending in the vertical direction is formed in the discharge port 25. Molten slag 2 that is connected and falls in a predetermined lump shape
7 can be cooled and solidified in a slag cooling water tank 9 (see FIG. 1). A flue 28 is provided in the middle of the exhaust passage 26, branching off from this and slanting slightly upward, and the combustion exhaust gas is sucked in by a blower 29, cooled by an exhaust gas cooler 30, and then released into the atmosphere. I'm starting to do that.

The melting furnace 11 configured as described above is provided with a moving layer transfer means 31, which is a feature of the present invention. This transfer means 31 is for controlling the transfer amount by changing the moving speed of the moving layer 10, and is composed of a moving layer pushing member 32 and a piston mechanism 33 for moving the moving layer pushing member 32 into and out of the furnace. There is.

The moving layer extrusion member 32 is formed by molding heat-resistant ceramics or the like into a rectangular shape so that its length and width are approximately the same as the length and width of the hearth 16. The upper side wall is penetrated so that it can be slid in an inclined direction along the hearth, and residues etc. can be forcibly transferred by the tip residue abutting surface 34.

The proximal end of the pushing member 32 is connected to the piston rod 35 of the piston mechanism 33 by a pin joint, so that the pushing member 32 can be moved into and out of the furnace. This piston mechanism 33 is configured so that its working distance, that is, the stroke, working interval, and working speed of the piston rod 35 can be changed arbitrarily by a control means (not shown).
The amount of movement of the moving layer is controlled.

In the above embodiment, the hearth 16 is integrally molded with a single piece of ceramic, and the combustion air is supplied from the side wall of the furnace. However, the present invention is not limited to this, and for example, as shown in FIG. Similarly, the hearth plate 36 may be formed into a rectangular shape using ceramics or the like, and the ends thereof may be overlapped and adjacent to each other in the direction of inclination of the furnace to form the hearth. Combustion air may be supplied from the lower part of the moving bed 10 to the moving bed 10 through a wind box 37 formed at the lower part of the hearth and a slit 38 as an air blowing port formed at the overlapping part of the fire bed plate 36. good.

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. Melting furnace 11 connected to the end of 1
is supplied into the incineration residue inlet 13 of the incineration residue. During combustion in the above incinerator, the amount of unburned carbon in the residue is 7 to 7.
Combustion is controlled so that it remains in the range of 25%, preferably 10-20%.

Specifically, combustion control is performed by adjusting the amount of garbage input, the amount of air for combustion, the stoker feed rate 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 grate plate 15 in the melting furnace 11, and this stacked residue is moved by the moving bed extrusion member 32 of the moving bed transfer means 31. Moving layer 1 while being pushed
0 and flows down in the direction of inclination.

On the other hand, the combustion air transferred through the combustion air supply pipe 19 is supplied into the moving bed from the combustion air inlet 22, whereby unburned carbon is combusted and the incinerated ash is melted by the heat generated at this time. will be done. In this way, since air is supplied directly into the moving bed from the sides of the moving bed, the residue is burned from the inside, and the incineration residue is completely melted without leaving the inner part unmelted. will be done. In addition, by burning the incineration residue from within, the combustion heat is maintained in the moving layer with little heat radiation and contributes effectively to the melting of the incineration residue, and the molten state of the molten slag is maintained. , hearth 1
6. It is possible to suppress the adhesion and solidification of molten slag to the furnace wall, or it is possible to remove the adhered and solidified slag.

This molten slag is heated by the heating element 20 of the heating means 17.
The molten slag flows on the grate plate 15 heated to a high temperature, that is, above the melting point of the molten slag, or is pushed away by the moving bed extrusion member 32, and becomes molten slag of a predetermined size from the lower end slag discharge port 25, and is discharged from the molten slag discharge passage. 26 and is cooled and solidified in the slag cooling water tank 9.

The combustion exhaust gas is sucked in by the blower 29 in the same direction as the molten slag flows out, and is discharged from the flue 28 while preventing the outlet 39 of the grate plate from being cooled. In this way, the extrusion member 32 normally moves back and forth continuously or intermittently within the furnace at a constant speed, or the extrusion member 32 is pushed out part way and then returned without moving to the end of the stroke, and the extrusion member 32 is moved in a constant amount at a time. Burning and melting are taking place.

Here, if it becomes necessary to increase the amount of combustion or melting of the in-furnace residue due to load fluctuations, for example, the operating distance, operating interval, or operating speed of the piston mechanism 33 is increased. As a result, the piston rod 35 extends to the stroke end, increasing the operating distance of the pushing member 32 connected thereto, shortening the operating interval of the pushing member 32, or increasing the reciprocating operating speed. Combined operations can increase the amount of combustion melt.

Further, in order to reduce the amount of combustion melt, the operation described above is reversed.

In this way, by sliding the extrusion member 32 into the furnace, it is not only impossible to control the amount of combustion melt as described above, but also the amount of combustion melt cannot be controlled as described above.
It is possible to remove the slag that has adhered and hardened to the surface of the slag 8, and also prevent the occurrence of crosslinking. Furthermore, the hearth 1 without melting
It is also possible to forcibly discharge the so-called unsuitable materials remaining in the melting process 6, thereby enabling stable operation.

In addition, even after the unburnt carbon has burned out, the molten slag remains molten due to the constant supply of heat from the grate plate 15 heated above its melting point, so it adheres to the hearth 16 and the furnace walls. It is possible to suppress solidification or to remove the adhered and solidified slag, and it is possible to prevent clogging of the furnace due to crosslinking of the molten slag.

Furthermore, by providing the heating element 20, it is possible to heat the incineration residue with heat other than combustion heat, so this combustion is promoted, and during low negative operation or when there is little unburned carbon in the residue. can also handle this.

Furthermore, since combustion air is supplied to the incineration residue and the residue is combusted, the incineration residue can be combusted at low cost without the need for expensive equipment.

Next, a second embodiment will be described based on FIG.

Components that are the same as those in the first embodiment are given the same reference numerals and explanations will be omitted.

In this second embodiment, a so-called moving bed type stoker 41 is employed as the moving bed transfer means 40.

This stoker 41 has a chain roller 4 between a pair of sprockets 42, 42 which are rotatably provided at the upper and lower ends of the bottom of the casing 12 in the inclined direction.
3, and a chain roller 43 is continuously connected to a ceramic grate plate 44 formed into a rectangular shape.

As the grate plate 44 moves, the residual moving layer 10 is sequentially transferred downward in the inclination direction within the furnace.

Therefore, in order to control the amount of combustion and melting, the moving speed of the moving bed 10 is changed by changing the operating speed or the operating interval of the stoker 41 serving as the moving bed transporting means 40, thereby controlling the amount of moving bed 10 transferred. Do it under control.

Incidentally, in the above embodiments, the moving bed transferring means has been described as an extrusion type or a moving bed type, but is not limited thereto, and may be, for example, a conveyor type.

Further, although the heating element 20 is provided at the lower part of the hearth etc. to heat the moving bed from the lower part, the present invention is not limited to this, and it may also be done through the side or upper furnace wall, for example. Alternatively, the heating element 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) Supplying combustion air from the air inlet to the moving bed formed by the hearth by the combustion air supply means, and changing the operating interval, working distance, and operating speed of the moving bed transporting means to move the moving bed. By changing the amount of transfer, all of the incineration residue can be melted at low cost, and by controlling the amount of transfer of the moving bed, the amount of combustion and melting of the residue can be controlled.

(2) By forcibly transferring the residue, good contact between the residue and the combustion air is achieved, and in conjunction with the reason stated in item 1 above, combustion efficiency can be improved.

(3) It is possible to suppress the adhesion and solidification of molten slag to the hearth and furnace walls, or to remove the molten slag that has adhered and solidified to the hearth and furnace walls, thereby preventing bridging thereof.

(4) It is possible to forcibly discharge so-called unmelted substances that do not melt, and in conjunction with the reason stated in the above 3, it is possible to prevent clogging in the furnace and perform stable operation.

[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 longitudinal cross-sectional view showing a first embodiment of the present invention, and Fig. 3 is a section A in Fig. 2. FIG. 4 is a longitudinal sectional view showing a modification of the first embodiment, and FIG. 5 is a longitudinal sectional view showing a second embodiment of the present invention. In the figure, 1 is an incinerator, 10 is a moving bed, 11 is a melting furnace, 16 is a hearth, 19 is a combustion air supply means,
22 is a combustion air blowing port, 24 is a combustion air supply pipe, 31 and 40 are moving bed transfer means, 32 is a moving bed pushing member, 33 is a piston mechanism, and N is an incineration residue.

Claims (1)

[Claims] 1. In an incineration residue processing device that burns unburned carbon contained in incineration residue discharged from an incinerator to obtain molten slag, a furnace in which the discharged incineration residue flows down to form a moving layer. a melting furnace having a floor; a combustion air supply means having an air inlet opening into the moving bed of the incineration residue; 1. An incineration residue processing device comprising a moving layer transfer means for changing the moving speed of the layer.