JP3073851B2 - Waste incineration melting treatment device and incineration melting treatment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid waste such as radioactive miscellaneous solid waste, toxic waste, and general waste generated in a nuclear facility and the like, and the incinerated ash is melt-processed. And an incineration melting treatment method.

[0002]

2. Description of the Related Art An apparatus for incineration and melting of radioactive miscellaneous solid waste and toxic waste is disclosed in Japanese Patent Publication No. 4-58598. This apparatus is provided with an induction heating coil, a melting vessel induction-heated by the induction heating coil, and an oxygen supply pipe for supplying an oxygen-containing gas into the melting vessel. In this apparatus, while the melting container is induction-heated, the miscellaneous solid waste and the flux are charged into the melting container and melted to form a molten material. Into the melting vessel little by little, and by supplying oxygen-containing gas from the oxygen supply pipe into the melting vessel, combustible miscellaneous solid waste is incinerated little by little on the melt. I have. In this case, the incinerated ash generated by the incineration is melted to become a molten material.

[0003]

However, in the above-mentioned conventional construction, since only a small amount of miscellaneous solid waste can be incinerated little by little, it takes a very long time to incinerate a large amount of miscellaneous solid waste. In practice, only small amounts of miscellaneous solid waste could be incinerated. In the above configuration, the reason that only miscellaneous solid waste can be incinerated little by little is that because incineration is performed on the melt while melting, when a large amount of miscellaneous solid waste is put on the melt in the melting vessel, This is because incomplete combustion occurs.

Accordingly, an object of the present invention is to provide a waste incineration melting treatment apparatus and incineration melting apparatus capable of promptly incinerating a large amount of solid waste and smoothly melting ash generated by the incineration. To provide a processing method.

[0005]

According to the present invention, there is provided an apparatus for incinerating and melting waste, comprising a furnace body having an upper portion as a combustion zone.
A melting vessel is provided in the furnace body below the combustion zone, contains a solid waste, incinerates and melts the incinerated ash.The melting vessel is provided on an outer peripheral portion of the furnace body. It is characterized in that an induction heating coil for induction heating is provided, and an oxygen-containing gas supply device for supplying an oxygen-containing gas into the combustion zone of the furnace body is provided.

Further, in the waste incineration melting treatment method of the present invention, solid waste is put into the melting container while the melting container is induction heated by an induction heating coil to maintain the temperature at or above the incineration temperature. At the same time, by supplying the oxygen-containing gas from the oxygen-containing gas supply device into the combustion zone of the furnace body, the solid waste is incinerated and ashed in the melting vessel, and at the time of this incineration, the solid waste is incinerated. Performing a step of burning combustible gas generated from the combustion zone,
Thereafter, the step of melting the incineration ash accumulated in the melting container while performing induction heating of the melting container by the induction heating coil and maintaining the melting temperature higher than the incineration temperature is performed. Having. Although it is possible to incinerate at a melting temperature at one time, there is a problem that a large exhaust gas treatment system is required to treat a large amount of combustibility.

[0007]

According to the above means, first, only solid waste is incinerated. Specifically, while the melting vessel is induction-heated and maintained at a temperature not lower than the incineration temperature, solid waste is charged into the melting vessel and oxygen is supplied from the oxygen-containing gas supply device into the combustion zone of the furnace body. By supplying the contained gas,
Solid waste is incinerated in the melting vessel and incinerated. At this time, the combustible gas generated from the solid waste is completely burned in the combustion zone. Therefore, even if a large amount of solid waste is put into the melting vessel, incomplete combustion does not occur, and the waste can be quickly incinerated.

After the above incineration is performed, the incineration ash accumulated in the melting container is melted. In this case, the incineration ash can be smoothly melted by inductively heating the melting container and maintaining the melting temperature higher than the incineration temperature.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. FIG. 1 shows a longitudinal section of the entire incineration melting treatment apparatus. In FIG. 1, a support frame 1 is erected on a foundation, and a closed vessel-shaped furnace body 2 is supported on the support frame 1. The furnace main body 2 includes a cylindrical side wall 3 made of a nonmetallic material, for example, quartz, and a metal lid 4 attached to an upper end of the side wall 3.

A guide 5 is provided upright on the foundation, and an elevator 6 is guided by the guide 5 so as to be able to move up and down. The lift 6 is configured to be driven up and down by a drive device such as a motor (not shown). A bottom cover 7 for opening and closing a bottom opening of the furnace body 2 is fixed to an upper portion of the elevating table 6. Further, an induction heating coil 8 is provided on the outer peripheral portion of the side wall 3 of the furnace main body 2. The induction heating coil 8 is housed in a cover 9 and is configured to be cooled by a cooling method such as air cooling or water cooling.

On the other hand, a cylindrical heat insulating wall 10 made of a heat insulating material such as castable is provided inside the side wall 3 of the furnace body 2. In the middle part of the peripheral wall of the heat insulating wall 10,
A hole 11 is formed, and an oxygen-containing gas supply device such as a blower 12 provided outside through the hole 11.
Thus, combustion air is supplied into the heat insulating wall 10 from the inside. In this case, the upper part in the heat insulating wall 10 is the combustion zone 1
The upper part of the furnace main body 2 is a combustion zone 13. Further, the combustion air is configured to be introduced tangentially to a cylindrical combustion zone in order to improve combustibility, and a swirling flow is generated in the combustion zone.

A nonmetallic support 14 such as a heat insulating material is fixedly mounted on the upper surface of the bottom cover 7, and a melting vessel 15 is placed on the support 14. . This melting vessel 15 is made of a ceramic heating element, preferably C-S
It is made of iC or C-Al2 O3 ceramic. The melting vessel 15 is configured to be able to be inserted and removed from below in the heat insulating wall 10 by being driven up and down together with the bottom lid 7 and the support 14. Thus, the melting vessel 15 is arranged below the combustion zone 5 in the furnace main body 2.

Further, the lid 4 of the furnace main body 2 has a waste inlet 16 for introducing radioactive miscellaneous solid waste into a melting vessel 15, and an exhaust gas generated when the miscellaneous solid waste is incinerated. An exhaust gas outlet 17 for discharging the exhaust gas is provided.
Exhaust gas and the like discharged from the exhaust gas discharge port 17 are filtered by a well-known filter device (for example, a ceramic filter and an H filter).
(Made of an EPA filter) to remove radioactive ash contained therein. It is also preferable to provide an afterburner for more complete combustion before leading it to the filter device. The lid 4 of the furnace body 2 is provided with a detection device (not shown) for detecting the incineration state and the melting state in the melting container 15. This detecting device includes a radiation thermometer for detecting the temperature in the melting vessel 15, a laser level gauge for detecting the position of the molten metal level in the melting vessel 15, a TV camera for a monitor TV, and the like. It is provided with.

Next, an operation process for incinerating and melting radioactive miscellaneous solid wastes by the incineration / melting treatment apparatus having the above configuration will be described. In this case, first, a high-frequency current is applied to the induction heating coil 8 to heat the melting container 15 by induction, and the temperature in the melting container 15 is set to an incineration temperature, for example, 700 to 1.
Set to about 000 ° C or higher. Then, at this temperature, miscellaneous solid waste is charged into the melting vessel 15 through the waste input port 16, and combustion air (oxygen-containing gas) is supplied from the blower 12 into the combustion zone 13 of the furnace body 2. Supply. As a result, the miscellaneous solid waste charged into the melting vessel 15 is incinerated and ashed, and the combustible gas generated from the miscellaneous solid waste during the incineration is removed from the combustion zone 13.
And the solid waste is completely burned. Less than,
Until the inside of the melting container 15 is almost full of incineration ash, the operation of injecting and burning the miscellaneous solid waste is continued. Thereby, a large amount of miscellaneous solid waste can be quickly incinerated in a short time.

Thereafter, when the inside of the melting vessel 15 is almost full of incineration ash, the introduction of the miscellaneous solid waste is stopped, and the temperature of the melting vessel 15 when the induction heating is performed by the induction heating coil 8 is increased. . Specifically, the temperature of the melting container 15 is set to a melting temperature higher than the incineration temperature, for example, 140.
The temperature is set and maintained at about 0 to 1700 ° C. Thereby, the incineration ash accumulated in the melting container 15 is melted.

When all of the incineration ash in the melting vessel 15 is melted, the volume thereof is considerably reduced. Therefore, miscellaneous solid waste (in this case, non-combustible miscellaneous solid waste) is added to the melting vessel 15. It is possible to put and melt. Therefore, after all the incineration ash in the melting vessel 15 is melted, non-combustible miscellaneous solid waste (metal, heat insulating material, concrete, etc.) is additionally charged into the melting vessel 15, and the inside of the melting vessel 15 is filled. Melt until almost full with melt.

When the melting has progressed until the inside of the melting vessel 15 is almost full of the melt, the induction heating by the induction heating coil 8 is stopped, and the melt is cooled and solidified by natural cooling. Subsequently, the solidified material is stored together with the melting container 15 in a drum, and cement mortar is poured into the drum and solidified. As a result, a stable melt-solidified body (drum-packed body) most suitable for transportation and storage is formed.

In the above embodiment, after the incineration ash is melted, non-combustible miscellaneous solid waste is additionally introduced and melted. Instead, combustible miscellaneous solid waste is added. You may make it throw in and incinerate. Specifically, when all of the incineration ash in the melting container 15 is melted, the temperature of the melting container 15 is lowered, and the incineration temperature of 700 to 10
The setting is kept at about 00 ° C. Thereby, the melting container 1
The melt in 5 solidifies. Then, after the melt is solidified, the miscellaneous solid waste is additionally incinerated in the same manner as in the incineration step described above by introducing the miscellaneous solid waste into the melting container 15 through the waste input port 16. .

Such additional incineration is continued until the inside of the melting vessel 15 is almost full of incineration ash. Thereafter, when the inside of the melting container 15 is almost full of incineration ash, the charging of the miscellaneous solid waste is stopped, and the temperature of the melting container 15 is raised to about 1400 to 1700 ° C., which is the melting temperature. Keep settings. Thereby, the additional incineration ash accumulated in the melting container 15 is melted. Hereinafter, such additional incineration and additional melting are repeatedly performed until the inside of the melting container 15 becomes substantially full of the melt. Therefore, also in this modified example,
It is possible to obtain substantially the same operation and effect as the above-described embodiment. In particular, in this modification, the combustible miscellaneous solid waste can be incinerated and melted in a larger amount.

In each of the above embodiments, air is supplied as an oxygen-containing gas to the combustion zone 13 of the furnace body 2 by the blower 12, but the invention is not limited to this.
Air with high oxygen concentration instead of air or almost 100%
It is good also as a structure which supplies oxygen gas.

In the present invention, the temperature of the melting vessel is made different between the time of incineration and the time of melting. However, if the exhaust gas system is made larger than that of the present invention, the temperature of the incineration melting is not changed. Clearly what you can do.

In the above embodiment, the height of the combustion zone 13 in the vertical direction is configured as shown in FIG. 1. Instead, the height of the combustion zone 13 in the vertical direction is further increased. Alternatively, the configuration may be such that the combustion efficiency is improved. In this case, it is preferable that the combustion air is sent so that a desired swirling flow is generated in the combustion zone. Further, when the vertical dimension of the combustion zone cannot be increased, the combustion zone may be extended laterally to secure a required combustion distance.

[0023]

As is apparent from the above description, the present invention provides a combustion zone in the upper part of the furnace body and an oxygen-containing gas supply device for supplying an oxygen-containing gas into the combustion zone. The solid waste was put into the melting vessel and incinerated and ashed while maintaining the melting vessel at or above the incineration temperature, and thereafter, accumulated in the melting vessel while maintaining the melting vessel at the melting temperature. Since the incineration ash is melted, a large amount of solid waste can be promptly incinerated, and an excellent effect that the ash generated by the incineration can be smoothly melted is exhibited.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an incineration melting treatment apparatus showing one embodiment of the present invention.

[Explanation of symbols]

2 is a furnace main body, 8 is an induction heating coil, 10 is a heat insulating wall, 12
Denotes a blower (oxygen-containing gas supply device), 13 denotes a combustion zone, and 15 denotes a melting vessel.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-38698 (JP, A) JP-A-4-286999 (JP, A) JP-A-60-38700 (JP, A) JP-A 61-386 209399 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G21F 9/32 G21F 9/30

Claims (2)

(57) [Claims] 1. A furnace body having an upper portion as a combustion zone, a melting container provided below the combustion zone in the furnace body, for containing and incinerating solid waste and melting the incinerated ash, Incineration of waste comprising an induction heating coil provided on the outer periphery of the furnace main body for induction heating the melting vessel, and an oxygen-containing gas supply device for supplying an oxygen-containing gas into a combustion zone of the furnace main body. Melt processing equipment. 2. A solid waste is charged into the melting vessel while the melting vessel is induction heated by an induction heating coil and maintained at the incineration temperature, and a combustion zone of the furnace body is supplied from the oxygen-containing gas supply device. Supplying the oxygen-containing gas into the incineration and incineration of the solid waste in the melting vessel, and burning the combustible gas generated from the solid waste in the incineration in the combustion zone. And a step of melting the incineration ash accumulated in the melting container while inductively heating the melting container by the induction heating coil and maintaining the melting temperature higher than the incineration temperature. Incineration melting treatment method.