JPS62140096A - Storage device for radioactive substance vessel - 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 Technical Field of the Invention The present invention relates to a storage device for a container (hereinafter referred to as a cask) in which a radioactive substance is sealed.

[Technical background of the invention and its problems] In recent years, with the development of the use of radioactive substances, the use of radioactive substances has increased. For example, a nuclear power plant uses a large amount of radioactive materials as nuclear fuel, so spent fuel is generated as the nuclear power plant ages. Moreover, with the expansion of nuclear power plants, large amounts of spent fuel are being generated every year. Usually, spent fuel is transported to a reprocessing facility using casks or the like, and is reprocessed there. This reprocessing M! In order to ensure smooth operation at power plants and reprocessing plants, it is necessary to install cask storage equipment at power plants and reprocessing plants.

By the way, a cask that stores radioactive materials must have the functions of sealing the radioactive materials and shielding them from radiation, transmitting the heat generated by the radioactive materials to the outside, and maintaining the radioactive materials at a stable temperature. It is. For example, a cask that stores spent fuel from a nuclear RFI plant contains dozens of spent fuels that have been used for five years after being removed from the reactor. At this time, from one cask, the late K
Approximately several tens of kilowatts of heat is released from W. In cask storage equipment, casks are stored in tens to hundreds of countries, and therefore large-scale cask storage equipment can store hundreds of kilowatts.
Heat will be released.

In general, such a storage device is required to minimize the radiation dose to the surrounding area and to have sufficient reliability over a long period of time.

Next, a conventional radioactive material container storage device shown in FIG. 5 will be explained. In the same figure, cask 2 is storage R1
They are arranged independently at regular intervals within the storage area, and in order to keep the exposure dose to the area around storage area 1 as low as possible, this storage area 1
The side surfaces 3 and the ceiling 4 are constructed of concrete walls that have a radiation shielding function. In addition, inside the storage 1, there is a possibility that the movement of the cask 2 within the storage 1 and the cask 2
An overhead crane 5 is provided to facilitate loading and unloading. Note that 6 is the roof.

In the conventional radioactive material container storage device described above,
Most of the heat generated from the cask 2 is discharged to the outside through a gap in the ceiling 4 (not shown) through the space between the ceiling 4 and the roof 6 due to natural convection of the air that has flowed into the storage 1, and Some of the heat generated by the car was also transmitted to the surrounding concrete walls by radiation.

Therefore, the concrete wall is exposed to high temperatures for a long period of time, and its integrity is significantly impaired due to dehydration and the like, so that there is a problem in that the concrete wall must be actively cooled in some cases.

[Object of the Invention] The present invention was made in view of the above circumstances, and its purpose is to provide a cask storage device whose reliability and safety are improved by shielding the heat emitted from the cask. It is in.

[Summary of the Invention] In order to achieve the above object, the present invention relates to a storage device for radioactive material containers in which a heat shield for shielding radiant heat is provided inside a building in which the radioactive material containers are stored.

[Embodiments of the invention] Embodiments of the present invention will be described with reference to the drawings.

Components that are the same as those of the conventional cask storage device shown in FIG. 5 will be described with the same reference numerals.

FIG. 1 is a cross-sectional view of an embodiment of the present invention. In the figure, casks 2 are arranged independently at regular intervals in a storage 1, and the radiation exposure to the vicinity of the storage 1 is kept as low as possible. The sides 3 and ceiling 4 of this storage 1 are constructed of concrete walls having a radiation shielding function.

Further, a heat shield 7 is provided inside the side wall 3 and ceiling 4 of the storage 1, and the side wall 3 and ceiling 4 are configured so as not to be directly exposed to radiant heat from the cask 2. Note that 6 is a roof, and an overhead crane 5 is provided inside the storage 1 to facilitate the movement of the casks 2 within the storage 1 and the loading and unloading of the casks 2.

Since the present embodiment is configured as described above, the air flowing into the storage 1 is heated by the heat generated from the cask 2 and passes through the gap between the ceiling 4 and the roof 4 (not shown).
It is discharged to the outside through the space between the At this time, the heat generated from the cask 2 is shielded by the heat shield 7, so the concrete walls of the side wall 3 and ceiling 4 of the storage 1 are not heated as in the conventional case, and the health of the storage 1 is further improved.

By the way, the heat shield 7 is not particularly limited as long as it has a heat shielding effect, and is made of a material with metallic luster, for example.

FIG. 2 is a perspective view of the heat shield 7 according to the present invention, which has a configuration in which a plurality of mountain-shaped heat shield plates 8 are arranged horizontally with appropriate gaps.

FIG. 3 is a perspective view of another heat shield 9 according to the present invention, in which a plurality of mountain-shaped heat shield plates 8 are arranged vertically with appropriate gaps.

These Figs. 2 and 3 4. Mountain-shaped heat shielding plate 8
This design takes into consideration the flow of coolant, and its cooling effect is superior to that of a flat plate. In order to roughly prevent leakage of radiant heat, the heat shielding effect can be roughly enhanced by arranging the heat shielding plates 8 so as to optically overlap each other.

FIG. 4 is a sectional view of another heat shield 10 according to the present invention. As shown in the figure, the heat shield 10 has a neutron shielding resin 12 and a γ-ray shielding lead plate 13 inside. The laminate is covered with a heat shielding aluminum plate 11,
When such a heat shield 10 is installed inside the storage 1, it can have both a heat shield function and a radiation shield function.

[Effects of the Invention] As explained above, according to the present invention, by installing a heat shield with an extremely simple structure inside the storage, radiant heat to the walls, ceiling, and roof can be blocked. It is possible to prevent the temperature rise of concrete, which is the main structure of walls, ceilings, and roofs, and further improve the safety and soundness of radioactive material container storage devices over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a sectional view of one embodiment of the present invention, FIGS.
Each figure is a perspective view of a heat shield according to the present invention, FIG. 4 is a sectional view of another heat shield according to the present invention, and FIG. 5 is a sectional view of a conventional storage device for a radioactive substance container. 1...Storage, 2...Cask 3...
Side wall, 4...Ceiling 7, 9.10...Heat shield 8...Heat shield agent Patent attorney Nori Chika Ken Yudo Hirofumi MitsumataFigure 1Figure 2Figure 3Figure 4

Claims (4)

[Claims] (1) A storage device for radioactive material containers, characterized in that a heat shield for blocking radiant heat is provided inside a building in which radioactive material containers are stored. (2) The storage device for a radioactive substance container according to claim 1, wherein the heat shield comprises a radiation shielding material. (3) The storage device for a radioactive substance container according to claim 1, wherein the heat shield includes a plurality of heat shield plates arranged with gaps so as not to obstruct the flow of the coolant in the storage. (4) The storage device for a radioactive substance container according to claim 3, wherein the heat shield plate has a substantially chevron shape.