JPH0249598Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an improvement of a storage basket for radioactive waste.

Currently, most of the non-flammable radioactive solid waste generated from nuclear facilities is temporarily stored in untreated storage or underwater in pits.
These wastes continue to accumulate, and the storage capacity of storage bins or pits is becoming a problem.
Therefore, in order to improve this storage efficiency, waste volume reduction treatment is being implemented. Volume reduction methods include disassembly, compression, fragmentation, and melting. Disassembly methods include separating the waste by cutting or removing fasteners, and tightly bundling the separated parts or tightly placing them in storage containers. It is designed to reduce the volume by storing it.

Fuel inserts, such as burnable poison aggregates used in pressurized water reactors, have traditionally been stored in pits as they are after use, which significantly reduces pit storage efficiency. Ta. The above poison aggregate has a diameter of approximately 10 mm and a length of 4
10 to 20 rods of 1.5 m in length are attached to the holder at a pitch of about 40 mm, so if this is disassembled and stored in a basket, the volume can be reduced to about 1/10.

In order to densely store each poison rod after disassembling and separating the above-mentioned aggregate into a basket, the basket generally adopts a structure in which the basket is divided into small compartments for each poison rod. If a poison rod is supplied to each section, if the poison rod is bent, it will not enter the section completely and will protrude significantly upward. It is necessary to completely push these poison rods into each compartment, but there are usually over 100 compartments in one basket, and it is extremely difficult to align each one underwater and push the poison rods into each compartment. It is complicated.

This invention was made to eliminate these conventional drawbacks, and the basket lifting frame attached to the upper part of the basket body is configured to be retractable, so that the entire poison rod can be moved to each compartment in one operation. It is designed so that it can be pushed into the That is, this invention is a basket whose interior is divided into small compartments so as to store elongated waste in close proximity to each other, and whose upper part is open.
A frame body is arranged on the outside of the side wall at the top of the basket.
A spring that expands and contracts vertically is arranged between the frame and the side wall of the basket, the lower end of this spring is supported by the side wall of the basket, the upper end is supported by the frame, and the spring is applied to the frame from above. By pressing against the force of the frame, the upper end of the frame is lowered to near the upper end of the basket.

Embodiments of this invention will be described below with reference to the drawings. In Figures 1 and 2, basket 1
consists of a basket body 2 and a frame 3, and the frame 3
is connected to the main body 2 via a spring 6 and a guide rod 5 so as to be movable up and down. A large number of partition plates 21 are formed inside the main body 2 in a grid pattern, and elongated waste material, such as a poison rod 4, is inserted into each compartment partitioned off by the partition plates 21. Note that in the drawing, the number of compartments is reduced for clarity. Further, a hole 23 having a diameter smaller than the diameter of the poison rod is formed in each section in the bottom plate 22 of the main body 2, and each poison rod 4 can be pushed up through this hole 23 as described later.

The frame body 3 includes an upper plate 32 provided at the upper end of a peripheral wall 31, and an opening 30 of a size corresponding to the upper surface of the main body 2 is formed in the upper plate 32. A projection 33 is provided on the inside of the peripheral wall 31, and a projection 24 is provided on the outer surface of the main body 2, so that the distance between the main body 2 and the peripheral wall 31 is always kept constant by the projections 33 and 24. ing. 35 is a hole into which the guide rod 5 is inserted. At the four corners of the frame body 3, springs 6 are arranged between the protrusions 33 and 24, and guide rods 5 are provided to penetrate both the protrusions 33 and 24.
When force is applied to the frame 3 from above, the spring 6 is compressed and the frame 3 is lowered relative to the main body 2.

In the above structure, in order to insert the poison rod 4 into the basket body 2, it is fed into each compartment from above through the opening 30 by a supply means (not shown). Since each section is slightly larger than the outer diameter of the poison rod 4, if the poison rod 4 is bent, it will hit the partition plate 21 and will not reach the lower end due to the frictional force, as shown in FIG. As shown in the figure, the upper end of the poison rod 4 largely protrudes above the main body 2. Then, lift the basket 1 and press it against the ceiling plate 8 as shown in FIG. As a result, the frame 3 is first pushed downward against the force of the spring 6, and only the main body 2 rises, and the protruding poison rod 4 is pushed by the ceiling plate 8 and placed inside each compartment. Pushed in. When the basket 1 is lowered, the frame 3 is moved to the main body 2 by the force of the spring 6.
2, and each poison rod 4 is completely inserted into each compartment.

By configuring the frame 3 to be movable up and down relative to the main body 2 in this manner, a large number of poison rods 4 can be completely housed within the basket main body 2 by the simple operation of pressing the basket 1 against the ceiling plate 8. be able to. Next, in order to transport the basket 1 in which the poison rods 4 are tightly stored to a predetermined storage location, as shown by phantom lines in FIG. It is made to hang up by being locked in the hole 36 of. Although only one side is shown in the drawing, the claws 7 are locked symmetrically on both sides.

In the stored state, the upper ends of each poison rod 4 are located at the same height and close to each other, so it is very difficult to take out the poison rods 4 one by one during reprocessing. Therefore, as shown in FIG.
3, and each rod pushes up the poison rod 4 so that the upper end of the poison rod 4 protrudes by a different amount.

As explained above, this invention makes it possible to efficiently store elongated radioactive waste in a basket, and also allows each waste to be reliably stored in the basket with simple operations.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a basket showing an embodiment of this invention, FIG. 2 is a cross-sectional view taken along the line 2, and FIG. 3 is a cross-sectional view of the basket with the frame retracted. 1...basket, 2...basket body, 3
...Frame body, 4...Poison rod, 6...Spring.

Claims (1)

[Scope of utility model registration request] The basket is internally divided into small compartments for storing elongated waste in close proximity to each other, the upper part of which is open, a frame is disposed outside the side wall of the upper part of the basket, and the frame and the basket are connected to each other. A spring that expands and contracts vertically is arranged between the side wall and the lower end of the spring is supported by the side wall of the basket, and the upper end is supported by the frame body. 1. A storage basket for radioactive waste, characterized in that the upper end of the frame is lowered to near the upper end of the basket by pressing the basket.