JPH0517597U - Radioactive material storage - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] The present invention relates to a storage of radioactive materials, and by maintaining the soundness of the facility by monitoring and inspecting the inspection target area at any time by a simple method. Is meant to be confirmed. [Composition] A cell chamber 1 surrounded by a radiation shielding wall 2,
It is equipped with a plurality of storage tubes 5 arranged in the cell chamber 1 and a transparent window 17 arranged in the radiation shielding wall 2, and there is little radiation leakage outside the vicinity of the storage tubes 5 and the support structure 6. By creating an atmosphere that allows workers to enter, it is intended to improve monitoring and inspection.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a radioactive substance storage, and particularly, to improve the checkability of a storage pipe that stores a storage package and its supporting structure.

[0002]

[Prior Art]

 Generally, the high-level radioactive waste generated in a nuclear power plant or the like can be improved in handleability by subjecting it to a glass solidification treatment, for example. The so-called solidified package that has been subjected to glass solidification is planned to be stored in a radioactive waste storage for a long time as shown in Fig. 2.

In FIG. 2, reference symbol P is a storage package such as a solidified package obtained by subjecting high-level radioactive waste to vitrification, etc., and 1 is a cell chamber for storing a large number of storage packages P. 2 is a concrete wall surrounding the cell chamber 1, 3 is a transfer chamber provided above the cell chamber 1, 4 is a ceiling slab composed of concrete walls separating the cell chamber 1 and the transfer chamber 3, 5 Is a storage pipe (inner pipe) such as a steel pipe that is suspended from the ceiling slab 4 to store a plurality of radioactive wastes in a vertically stacked state, and 6 is a support structure that is horizontally installed in the cell chamber 1 ( Support frame), 7 is an outer tube which is supported by the support structure 6 and surrounds the storage tube 5, 8 is an outside air inlet, 9 is an air outlet, 10 is an air supply shaft, 11 is an exhaust shaft, and 12 is an accommodation Closure lid for sealing the upper part of tube 5, 13 Tube 5 and a tubular cooling channel is communicated with the and the air supply shaft 10 and an exhaust shaft 11 is formed between the outer tube 7.

In the storage having such a structure, when the temperature of the storage pipe 5 rises due to the decay heat of the radioactive material, convection occurs in which the air in the tubular cooling flow path 13 rises, as shown by the arrow in FIG. Further, the air taken in from the outside air inlet 8 cools it, and the heated air is discharged from the air outlet 9. Therefore, it does not require a power source and is cooled by natural convection during decay heat generation, which provides high safety without being affected by blackouts.

[0005]

[Problems to be solved by the device]

 However, since the radioactive substance is stored for a long time in such a storage, it is convenient that important parts such as the supporting portion of the storage pipe 5 and the cylindrical cooling flow path 13 can be inspected as necessary. Such technology has not been completed yet.

The present invention has been made in view of the above circumstances, and its purpose is to efficiently inspect necessary parts in a work environment with a low radiation level to confirm the soundness of a storage cabinet.

[0007]

[Means for Solving the Problems]

 In order to achieve such an object, in the present invention, a plurality of cell chambers surrounded by a radiation shielding wall and a plurality of radioactive storage packages that are arranged vertically in the cell chambers are loaded. It is a storage facility for radioactive materials having a storage pipe and a transparent window which is arranged on a concrete wall near the storage pipe or the support structure and is divided by a shield made of a radiation shielding substance.

[0008]

[Action]

 The outer portion of the see-through window is separated from the cell chamber by a radiation shielding wall and a shielding body made of a radiation shielding material, and the radiation shielding effect creates an atmosphere in which workers can enter. The inspection of the inspection target area will be carried out as needed through visual inspection through a transparent window.

[0009]

【Example】

 An embodiment of the radioactive substance storage according to the present invention will be described below with reference to FIG.

In FIG. 1 as well, portions common to those of FIG. 2 cited in the conventional example will be described with the same reference numerals.

In the embodiment, a plurality of side inspection rooms 14 and a lower inspection room 15 are arranged around the radiation shielding wall 2 made of a concrete wall or the like, and between the inspection rooms 14 and 15. Alternatively, a staircase 16 or the like is installed between the outside and the outside, and the radiation shielding wall 2 in the vicinity of the storage pipe 5 or the support structure 6 to be monitored is transparent and is made of a radiation shielding material. A number of see-through windows 17 constituted by a shield made of glass or the like are fitted therein.

The radiation shielding ability of the transparent window 17 is set to be equal to or more than that of the radiation shielding wall (concrete wall) 2, or a shielding plate or the like which is opened only at the time of inspection is added. .

Even in the storage cabinet having such a structure, when the temperature of the storage package P rises due to the decay heat of the radioactive material, the convection in which the air in the cylindrical cooling flow path 13 around the storage pipe 5 rises occurs. As shown by the arrow in FIG. 1, the air taken in from the outside air inlet 8 cools it, and the heated air is discharged from the air outlet 9.

The state of circulation of air to the tubular cooling flow path 13, in other words, the state of holding the annular space between the storage pipe 5 and the outer pipe 7, etc., is determined, for example, from the lower inspection room 16 through the transparent window 17. Then, it becomes possible to directly monitor and inspect by visual inspection, etc., and it is possible to confirm at any time that the soundness is not impaired.

Whether the support of the storage pipe 5 is normal, or whether there is any abnormality in the mounting position of the support structure 6 and the outer pipe 7 or whether corrosion or displacement has occurred is detected in the side inspection room 14 Also, the lower inspection room 16 can be checked at any time by monitoring and inspecting it through the respective transparent windows 17.

These monitoring and inspection operations should be carried out efficiently in an environment where there is little radiation exposure, that is, in the outer portion of the concrete wall 2 or the transparent window 17 by using the multiple transparent windows 17 as a necessary location. You can

In the embodiment described so far, the storage package P is a so-called solidified package that has been subjected to a treatment such as vitrification, but the storage package P is not limited to this and is generally It includes radioactive wastes packaged and spent fuels packaged.

[0018]

[Effect of the device]

 According to the radioactive substance storage according to the present invention, the radiation shielding wall surrounding the cell chamber is provided with the transparent window, so that the radiation leakage can be prevented from occurring outside the vicinity of the storage pipe or the supporting structure. Since it is designed to create an atmosphere in which a small number of workers can enter, it is possible to monitor and inspect the inspection target area at any time by a simple method such as visual inspection through a see-through window as needed. There is an effect such as being able to.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an embodiment of a radioactive substance storage according to the present invention.

FIG. 2 is a front sectional view showing a conventional example of a radioactive waste storage.

[Explanation of symbols]

 P Storage Package 1 Cell Room 2 Radiation Shielding Wall (Concrete Wall) 3 Transfer Room 4 Ceiling Slab 5 Storage Tube 6 Support Structure (Support Frame) 7 Outer Tube 8 Outside Air Inlet 9 Air Outlet 10 Air Supply Shaft 11 Exhaust Shaft 12 Closure Lid 13 Cylindrical cooling channel 14 Side inspection room 15 Lower inspection room 16 Stairs 17 Transparent window

Claims (1)

[Scope of utility model registration request] 1. A cell chamber surrounded by a radiation shielding wall, a plurality of storage tubes arranged in the cell chamber in a vertical direction and loaded with a radioactive storage package, and a storage tube or a support structure. A storage box for radioactive material, comprising: a transparent window which is arranged on a radiation shielding wall in the vicinity thereof and which is partitioned by a shield made of a radiation shielding material.