JPH0631873B2 - Radioactive waste treatment body - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

 The present invention relates to a radioactive waste disposal body.

BACKGROUND OF THE INVENTION

The low-level radioactive wastes stored and stored at nuclear power plants are scheduled to be stored off-site for the purpose of land disposal from 1969. Various treatment methods have been conventionally proposed for such low-level radioactive waste. As one of them, for example, a technology has been proposed in which a radioactive waste is solidified and filled with cement mortar in a container made of reinforced concrete having a size of 1600 × 1600 × 1320 mm and an epoxy lining on the inner surface and a thickness of 150 mm. However, some problems remain in the proposed technology. That is, since the container is made of reinforced concrete with a thickness of 150 mm, the weight of the container becomes heavy, the weight of solid waste of radioactive waste reaches about 10 tons, it is difficult to handle, and the cost is also high. high. In addition, special facilities are required to fit the existing handling system within the nuclear power plant. Further, since the handling hanging metal fittings are provided at the four corners, the cost is high. There is also the problem of breathing when placing concrete.

DISCLOSURE OF THE INVENTION

A first object of the present invention is to provide a radioactive waste treatment technique which is preferable in terms of disposal efficiency, transportation efficiency, particularly handling property, light weight and cost. A second object of the present invention is to provide a radioactive waste treatment technique which is highly safe, with a small amount of radioactive material leaching, especially in a long period of time, even though the processed material is lightweight. Especially. A third object of the present invention is to provide a radioactive waste treatment technology that is capable of withstanding various tests for accident assessment that are expected to occur during transportation to a disposal facility, such as drop tests, that is, is highly safe. Especially. The present invention has been made as a result of earnest research to achieve the above-mentioned object, and a radioactive waste is solidified and filled with a bubble paste in a container body in which steel plates are laminated and arranged outside a polymer-impregnated concrete layer. The present invention provides a radioactive waste disposal body in which the upper space of the solidified packing is closed by a capping material, and the capping material is covered by a lid.

【Example】

The drawing is a perspective view of a partially cut-away view of an embodiment of the radioactive waste disposal device according to the present invention. In the figure, 1 is a steel plate having a thickness of 1.6 mm, and this steel plate 1 constitutes the outer surface of the rectangular container body A. 2 is a 20 mm thick polymer-impregnated concrete layer provided so as to be laminated inside the steel plate 1. Incidentally, 3 is a base of the container body A. Reference numeral 4 is a low-level radioactive waste such as non-combustible waste put into the container body A. Reference numeral 5 is an aerated paste (a cement paste in which fine air bubbles are uniformly dispersed) having a specific gravity of about 1 to 1.5, which is filled with the radioactive waste 4 in the container body A in order to solidify the radioactive waste 4. 6 is a capping material filled in the upper space of the bubble paste 5 in which the radioactive waste 4 is solidified. Reference numeral 7 is a 1.6 mm thick steel plate forming the outer surface of the lid B, and 8 is a 20 mm thick polymer-impregnated concrete layer provided so as to be laminated inside the steel plate 7 of the lid B. The radioactive waste disposal body configured as above has a thickness
Even if a thin steel plate such as 1.6 mm is used, it is less likely to be damaged.For example, in a free fall test from a height of 1.2 m, the steel plate has some deformation and damage, but the contents are not scattered. , Because of its high durability,
It is highly safe. In particular, a thin steel plate is provided outside the polymer-impregnated concrete layer, so that the polymer-impregnated concrete layer is protected by this steel plate, and the durability is excellent. Furthermore, they also showed excellent results in various tests for evaluating accidents that may occur during transportation to the treatment facility. In addition, despite being highly durable as described above, the overall weight is not so high, for example, 1350 mm × 1350 mm × 1100.
The size and shape of mm is comparatively lightweight, such as 4.5 tons or less, and therefore it is easy to handle during transportation and the transportation cost is low. In addition, since the entire shape is square, it is difficult to form a gap even if they are arranged side by side during disposal, and thus the disposal efficiency is high and the handling property during transportation is good. In addition, although the aerated paste was used to reduce the weight of the radioactive waste disposal body, almost no leaching of radioactive materials to the outside was observed due to the combined action of both the polymer-impregnated concrete and the aerated paste. It is not safe, and it is highly safe. In particular, after long-term storage / storage, corrosion of the steel sheet is expected over time, but even without the steel sheet, leaching of radioactive material to the outside is hardly observed,
The safety is high over a long period of time. In addition, since the air bubble paste used as the solidifying material prevents the increase of surplus water by the fine air bubbles inside, it does not cause breathing.

【effect】

The radioactive waste disposal body according to the present invention comprises a container body in which steel plates are laminated and arranged outside a polymer-impregnated concrete layer, and radioactive waste is solidified and filled with an air bubble paste, and an upper space of the solidified filling is formed. Is capped with a capping material, and the capping material is covered with a lid, so that the disposal efficiency and transportation efficiency are good, and the handling is easy, and the cost is low, and the strength is high. It is excellent in safety and has little leaching of radioactive substances, and even if corrosion occurs on the steel sheet during storage and storage, leaching of radioactive substances is small and safety is high.

[Brief description of drawings]

The drawing is a perspective view of a partially cut-away view of an embodiment of the radioactive waste disposal device according to the present invention. A: container body, B: lid, 1,7 ... steel plate, 2,8 ... polymer-impregnated concrete layer, 3 ... base leg, 4 ... radioactive waste, 5 ... bubble paste, 6 ... … Capping material.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kanjiro Ishizaki 2-1-1 Tsukimi-cho, Kumagaya-shi, Saitama Chichibu Cement Co., Ltd. Related Products Division (72) Naoaki Koyanagi Tsukimi-cho, Kumagaya-shi, Saitama 2-1-1, Chichibu Cement Co., Ltd. Related Products Headquarters (72) Inventor Kei Sugawara 2-1-1, Tsukimicho, Kumagaya-shi, Saitama Chichibu Cement Co., Ltd. Related Products Headquarters

Claims (1)

[Claims] 1. A radioactive waste is solidified and filled by an air bubble paste in a container body in which steel plates are laminated and arranged outside a polymer-impregnated concrete layer, and an upper space of the solidified filling is closed by a capping material. The radioactive waste disposal body further characterized in that the capping material is covered with a lid.