JPS61286800A - Vessel packer for radioactive solid 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 The present invention relates to an apparatus for packaging radioactive waste, particularly non-flammable miscellaneous solid waste, from nuclear power plants or other facilities handling radioactive materials.

Since the radiation emitted from this unconventional radioactive waste has a tremendous impact on living things in the natural world, including humans, it is difficult to dispose of it until its final disposal (for example, dumping it in the ocean or burying it underground). You are required to keep this for a while.

In this case, as the above-mentioned waste is generally very incoming,
If stored as is, there is a problem in that a very large storage space is required. In order to eliminate any of these problems, the above waste is once melted in a crucible of a high frequency induction furnace or arc furnace, and the molten material is poured into a solidification container by tilting the furnace body and solidified. A method has also been considered in which the solidified material is transferred to a storage container for storage, but this method has the problem of requiring a lot of work during the process.

The present invention has been made to eliminate the above-mentioned problems, and aims to provide a radioactive waste container packaging device that can reduce the volume of the waste and also reduce the labor involved in the work. I have something to do.

Before describing the embodiments of the present application, a method for packaging small-sized release-resistant solid waste or compact radioactive solid waste will be described.

In FIG. 1, numeral 1 indicates non-flammable radioactive solid waste, ranging from large-sized waste 1a to small-sized waste 1b placed in container B2 as shown.

Such waste 1 includes metals (pipes, valves, plates, shaped steel, tools, etc.), waste filters (prefilters, HEPA filters), and inorganic materials (insulating materials, fireproof materials, glass, concrete, etc.) .

Furthermore, as is well known, such radioactive waste 1 is also
As shown in FIG. 4, radioactive nuclei f14 adhere to the surface of the solid object 1/ forming the above-mentioned pipe, filter, glass, etc., resulting in radioactive contamination.

The waste 1 is then melted in a melting furnace 5. Prior to the melting process of the lock, the large waste 1a is passed through a size reduction device 3 such as a plasma cutter, cutter, press, etc.
It is broken down into small pieces by

Further, the container 6 is prepared prior to the melting process. This container 6 is one that can be used as is for storage as described below, that is, one that is suitable for use as is for storage in terms of its structure, size, cost, fire resistance, etc. One example is metal (e.g. iron)
A crucible made of a refractory material (for example, graphite) 8t is provided in a canister 7 made of aluminum. This container 6 is placed on the transfer device 10 by a transfer device such as a crane 9.

The transfer device 10 includes a moving truck 11, a cylinder 12 fixed to the truck 11, a lower cover 13 attached to an advance/retractor 12a of the cylinder 12, and a pedestal 14. When the container 6 is placed on the pedestal 14 by the crane 9, the transfer device 10 is moved below the furnace body 15 in the melting furnace 5. Then, the cylinder 12 is extended, the lower lid 13 closes the lower opening of the furnace body 15, and the container 6 is positioned at a predetermined position within the furnace body 15.

The melting furnace 5 has a plasma torch 17, a lifting device 18 for raising and lowering the plasma torch 17, a waste carrying device 19, and a cooling device 20 for the container 6. Carrying device 1
Reference numeral 9 comprises a rail 21 installed within the furnace body 15, a packet 22 movable along the rail 21, and a cylinder 23 for moving the packet 22. Note that 24 indicates a valve, which is opened when the packet 22 moves.

The radioactive waste 1 is placed in a packet 22 and placed in the reactor body 1.
When the bottom plate of the packet 22 is opened, the packet 22 is introduced into the container 6 at a predetermined position. In this case,
The plasma torch 17 is being lifted up by a lifting device 18.

After the waste 10 has been charged as described above, the nokkeft 22 is pulled out of the furnace and the plasma torch 17 is lowered. The waste 1 in the container 6 is then heated by the high temperature plasma arc emitted from the plasma torch 17. This melts the waste 1. In this way, waste 1
When the waste 1 is melted, its bulk becomes smaller, so the waste 1 is again thrown in and the melting operation is performed in the same manner as described above.

During the above operation, cooling air is blown out from the cooling device 20 against the outer wall of the container 6 to protect the container 6 from overheating.

When the container 6 becomes full after repeating the above-mentioned operation several times, the container 6 is carried out from the furnace 5 by the moving device 10. It should be noted that the waste 1c in the container 6 (the state is different from that before melting, so the reference numeral will be changed in the explanation) is solidified before or during its removal.

Next, the container 6 that has been carried out is covered with a lid 25.

This lid 25 is welded to the container 6 by a welding device 26, and the inside of the container 6 is sealed.

The container 6 sealed in this manner is transported by arrow to a storage facility 27, where it is stored until it is disposed of in the ocean or otherwise disposed of.

Since the radioactive waste IC packed in the container 6 as described above has been melted as described above, it is solid as shown in Figure 2 (A) before melting. The radioactive nuclide 4 that had adhered to the surface of the object 1' was buried and mixed into the molten material, and when it solidified again, the radionuclide 4 was incorporated into the solid object 1/c that had once been melted and solidified. The situation is as follows. Therefore, part of the radiation emitted from nuclide 4 is blocked by the solid object 1/c, so
The amount of radiation coming out of the container 6 is small.

Next, FIG. 3 shows a different embodiment of the container. This container 6e is constructed by filling concrete 28 between a canister 7θ and a crucible 8e. The lid 29 is constructed by covering the inner surface of a metal outer plate with concrete.

The thickness of these concretes is the thickness required for final disposal (dumping into the ocean) as described above.

When using the container 6e configured in this way,
After storage as described above, it becomes possible to immediately transfer the material to final disposal. In this example, parts that are functionally the same or equivalent to those of the previous embodiment are given the same reference numerals as those of the previous embodiment with the letter e, and redundant explanations are omitted. (Furthermore, in the following example, the same concept is used, and redundant explanations are omitted by adding alphabetical characters.) Next, an embodiment of the present application will be described based on FIG. 4. In this example, large radioactive waste 1
a is directly melted without being subjected to size reduction as in the previous example. That is, the large-sized radioactive waste 1a is gripped by the gripper 33 of the melting device 31. This gripper 33 is configured to move up and down and rotate relative to the furnace body 32. Further, the furnace body 32 is equipped with a plurality of plasma torches 34. The waste 1a gripped by the gripper 33 is sequentially melted from its lower end by the high temperature plasma arc emitted from the torch 34 while being moved up and down or rotated.

The melted waste becomes drops and drips into the container 6f. When the drops drip into the container 6f and the container 6f becomes full, the container 6f is sealed and moved to a storage, as described above.

As described above, in the present invention, when the radioactive solid waste la is packed in the container 6f, the waste 1 which is larger than the container 6f is
A can be melted by the plasma arc from the plasma torch 34, and drops of the melted waste can be dripped into the container 6f and packed there, which has the effect of packing very large waste into a much smaller container. be. This has the effect of helping to save space when storing the radioactive waste, because even if the waste is originally electrified, the space required for storage can be reduced.

Moreover, in the above case, even if the waste 1a is very large, the plasma arc from the plasma torch 34, which is stable in its emitting direction, is transferred to the waste 1a.
Because it irradiates the target area, it can be irradiated accurately to the target area and melt it, and as a result, the droplet position can be determined accurately, and even if it is a small droplet 6F, it can be applied accurately. There are effects that can be packed inside.

Furthermore, in the above case, the radioactive waste is melted while suspended in the air,
Since the molten drops are directly dripped into the storage container 6f, there is an effect that separate equipment such as a container for melting the waste or a device for pouring the molten material into the storage container is completely unnecessary. be. Of course, in such a case, it is necessary to dispose of secondary waste generated when using an electric furnace (the refractories of electric furnaces and pouring equipment are contaminated with radioactivity, so a large amount of secondary waste is generated during repairs). There is no need for secondary waste to be generated), and it has the excellent effect of being able to solve the problems associated with the disposal of secondary waste in advance.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the treatment process of radioactive waste, Fig. 2 is a sectional view showing the composition of radioactive waste, Fig. 3 is a vertical sectional view showing different embodiments of the container, and Fig. 4 is an embodiment of the present invention. A diagram showing a container packaging device for radioactive waste. 1...Radioactive waste, 6...Container, 34...Plasma torch. Figure 2 (A'l Gumi)
Figure 3 Figure 4

Claims (1)

[Claims] A place for keeping a container that can be used for storage, a gripper for gripping radioactive solid waste at a position above the container placed in the above-mentioned place, and a radioactive solid waste gripped by the gripper. and a plasma torch for irradiating a plasma arc to the container, the radioactive solid waste is melted by the plasma arc above the container placed in the above location, and the droplets formed by the melt are dripped into the container. A container packing device for radioactive solid waste, characterized in that the radioactive solid waste is packed into the container.