JPS61213698A - Continuous melter for waste - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an apparatus for continuously melting waste, and more specifically to an apparatus for continuously melting waste at a high temperature of 1300 to 1600°C. It is.

(Prior technology) Conventionally, combustible waste contaminated with radioactivity generated from facilities handling radioactive materials such as nuclear power plants is generally incinerated, and the incinerated ash is filled into drum cans, etc. It is normally stored in an appropriate location within the facility. However, since these incinerated ash are in the form of powder and granules, when transporting or storing a drum can filled with incinerated ash, it is desirable to stabilize the incinerated ash and reduce its volume, and various methods for this treatment have been studied. ing.

Recently proposed treatment methods for radioactive waste include the first method of solidifying radioactive waste or incineration ash with cement.
The second method of mixing asphalt, plastic, etc. with radioactive waste or incineration ash and solidifying the mixture is well known. Furthermore, a third method has recently been proposed in which radioactive waste or incineration ash is heated and melted and solidified at high temperatures through batch processing.

(Problems to be Solved by the Invention) However, in the first method, the cement solidification method, it is difficult to mix waste or incinerated ash with cement to obtain a solidified product with stable density and strength. It is necessary to set the weight ratio of cement to 1 part of ash, etc. to 4 or more of cement, which has the drawback that the volume of the solidified material becomes larger than the volume of ash, etc., resulting in an increase in volume.

In addition, the second method, the asphalt and plastic solidification method, requires pretreatment such as removing metal pieces from waste or incineration ash and pulverizing it, which has the disadvantage of requiring complicated and large equipment. Ta.

Furthermore, in the third method, the heating melt solidification method,
Although the disadvantages caused by the first and second methods described above can be effectively eliminated, in order to melt the waste or incineration ash at a high temperature, a metal container is heated by electromagnetic induction to achieve a high temperature, It is limited to use at a temperature of 1,200°C, and it is not possible to melt waste that melts at higher temperatures.It is also a batch process, which requires a lot of time and effort to melt, and the disadvantage is that the amount processed at one time is small. there were.

The purpose of the present invention is to solve the above-mentioned problems and to
Waste or incineration ash can be melted even at high temperatures of 1600℃, converting it into a stable solidified material with reduced volume suitable for transportation and storage, and continuously with low heat loss and high melting speed. The object is to provide a continuous melting device for waste that can be melted.

(Means for Solving the Problems) The continuous waste melting device of the present invention has an upper part sealed with a top lid having a waste supply port and an exhaust gas port, and a bottom plate having a through hole in the center part. A furnace body sealed with
an electromagnetic induction coil provided on the outer periphery of the furnace main body; an abutment installed on the bottom plate inside the furnace main body and having a through hole in the center; A waste melting tank made of a ceramic heating element connects a melt discharge pipe inserted through the waste melting tank to the bottom thereof, and a shield suspended from above in the melting tank with a predetermined interval between the side wall of the waste melting tank. It is intended to be inserted and installed with strict standards.

(Function) In the present invention, the waste melting tank is C-3iC system, C-A I
! The waste melting tank is made with a ceramic heating element such as zOs, and the waste melting tank is directly heated by induction, and the heat melts the waste input into the melting tank from the waste input port.
It is configured so that it can be used even in the high temperature range of ~1600°C. At this time, the exhaust gas generated by the melting passes through the exhaust gas flow hole of the shield and is discharged from the gas exhaust port of the upper lid. The melt flows to the lower end of the shield and is discharged downward from the melt discharge pipe, but at this time, the melt discharge pipe is equipped with a regulating device to discharge or solidify the melt, so that the melt can be discharged at will. The structure is configured so that the discharge can be controlled and continuous melting processing can be performed.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a partial sectional view showing an embodiment of the continuous waste melting apparatus of the present invention. A furnace body 2 in the form of a closed container supported by a support frame 1 erected on a foundation is made up of a cylindrical side wall 3 made of a non-metallic material such as quartz, and a top cover 4 made of, for example, metal attached thereto. Become.

An induction heating coil 6 for main heating is attached to the outer periphery of the side wall 3. This induction heating coil 6 is housed within a cover 7 and is cooled by a known cooling method such as air cooling or water cooling. The bottom of the furnace body 2 is sealed by a bottom plate 5 having a through hole in the center. Inside the side wall 3, a support 11 having a through hole in the center on which the waste melting tank 12 is placed is provided on the bottom plate 5. This support 11 is made of a heat insulating material, and a melt discharge pipe 13 connected to the bottom of the waste melting tank 12 is inserted into the through hole. Moreover, a heat insulating cover 9 having at least two through holes for the waste supply port 8 and a through hole for the exhaust gas outlet 10 is provided on the upper part of the heat insulating wall 11a surrounding the support base 11.

In this embodiment, the shield 15 is installed in the waste melting tank 12 with a predetermined distance from the side wall of the waste melting tank 12 . The shield 15 has a cylindrical shape and is molded integrally with the heat insulator 119, and also communicates with the exhaust gas port 10.

Therefore, the exhaust gas in the melting tank 12 is discharged to the outside of the apparatus through the exhaust gas flow hole 1 - 4 provided in the upper part of the shield 15 and the exhaust gas port 10 . Furthermore, a gap is provided between the bottom of the melting tank 12 and the lower end of the shield 15 to allow the melt to flow. The shield 15 is made of fire-resistant ceramics or heat-resistant metal, and the waste melting tank 1
2 is preferably composed of a C-3iC type or C-A Iltow type ceramic heating element. Furthermore, the melting tank 12
The melt therein is stored in a container 16 through a melt discharge pipe 13.

In the continuous waste melting apparatus 20 having the above-described configuration, if the induction heating coil 6 is energized to induction heat the waste melting tank 12 made of a ceramic heating element, the melting tank 12
It self-generates heat and reaches a high temperature, making it possible to efficiently and continuously melt waste.

2 and 3 are main part sectional views showing other embodiments of the continuous melting apparatus of the present invention, and the same parts as in the embodiment shown in FIG. Omitted. Second
In the embodiment shown in the figure, in order to further improve the efficiency of induction heating in the waste melting tank 12, two rod-shaped internal heating elements 21 made of ceramic heating elements are installed in the heat insulating lid 9, and the melted material is discharged. A dissolution control device is provided for regulating the discharge or solidification of the melt in the tube 13. This elution control device connects only the outlet of the melt discharge pipe 13 to the air nozzle 22.
The molten material is cooled and solidified at the outlet by forced air cooling using compressed air. In the embodiment shown in FIG. 3, similar to the embodiment shown in FIG. By providing an induction heating coil 23 at a position corresponding to the discharge pipe 13, a frozen valve type elution control device is constructed.

In the continuous waste melting device configured as described above, in addition to continuously eluting the molten material, it is also possible to control the molten material to be eluted intermittently by performing forced cooling or induction heating with the elution control device. can.

The present invention is not limited only to the embodiments described above, and can be modified in many ways. By providing an oxygen supply pipe for supplying oxygen-containing gas and actively supplying the oxygen-containing gas into the melt, it is also possible to make it easier to burn the unburned content in the waste.゛Furthermore, if the furnace body 2 is highly insulated, the side wall of the support 11 and the heat insulating lid 9 may be omitted.

Further, in the above-described embodiment, the shielding body 15 is configured integrally with the heat insulating body 19, but the shielding body 15 may be a separate body.

(Effects of the Invention) As is clear from the detailed explanation above, according to the continuous waste melting device of the present invention, since the waste melting tank is constituted by a ceramic heating element,
It can be used safely even at high temperatures of °C, and since a shield is provided in the melting tank, the contact efficiency between the object to be melted and the heating element is improved, thermal loss can be reduced, and the melting speed can be increased. Therefore, it is possible to continuously melt and process radioactive waste that melts at 1300° C. or higher, which was previously impossible to melt. Furthermore, since the melt discharge pipe is provided with an elution control device, it is possible to control the elution of the melt intermittently.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the continuous waste melting device of the present invention, and FIGS. 2 and 3 are main part sectional views showing other examples of the continuous waste melting device of the present invention. be. 2...Furnace body 4...Top lid 5...Bottom plate
6...Induction heating coil 8...Waste supply port 10...Exhaust gas port 11...Abutment
12... Waste melting tank 13... Melt discharge pipe 1
5... Shielding body 21... Internal heating body 22...
Air nozzle 23...Induction heating coil Figure 1 town a

Claims (1)

[Scope of Claims] 1. A furnace body whose upper part is sealed with an upper lid having a waste supply port and exhaust gas port, and whose lower part is sealed with a bottom plate having a through hole in the center; an electromagnetic induction coil provided on the outer periphery; an abutment installed on the bottom plate in the furnace main body and having a through hole in the center; and an electromagnetic induction coil placed on the abutment and inserted into the through hole of the abutment. A waste melting tank made of a ceramic heating element that connects a melt discharge pipe to the bottom, and a shield suspended from above in the melting tank with a predetermined distance between the side wall of the waste melting tank and the waste melting tank. A continuous waste melting device characterized by the following: 2. The continuous waste melting apparatus according to claim 1, wherein the shield is made of a cylindrical body and is fixed to the upper lid. 3. Claim 1 or 2, wherein an annular melting chamber is formed between the shield and the side wall of the waste melting tank.
Apparatus for continuous melting of waste as described in Section 1. 4. The continuous waste melting apparatus according to claim 1, wherein an internal heating element made of a ceramic heating element on a rod is inserted into the waste melting tank. 5. The ceramic heating element is C-SiC type or C-A
The continuous waste melting apparatus according to claim 1 or 4, which is made of l_2O_3 ceramics. 6. The continuous waste melting device according to claim 1, which has an exhaust gas flow hole in the upper part of the shield in the waste melting tank. 7. The continuous waste melting device according to claim 1, wherein the melt discharge pipe has an elution control device for discharging or solidifying the melt in the pipe.