JPS6289000A - Method of filling and processing radioactive 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 (Field of Industrial Application) The present invention is a method for filling radioactive waste that can be compressed and reduced in volume, which is generated in nuclear facilities, etc., and then filled into storage containers in the most efficient manner. This relates to a processing method.

(Conventional technology) In the past, non-flammable radioactive waste generated from nuclear power facilities, etc. was stored in sealed containers such as drums in storage, but with the increase in radioactive waste in recent years, storage capacity has reached its limit. is approaching. For this reason, containers containing radioactive waste are compressed to less than a fraction of their volume using a large press machine, and then multiple compressed and reduced volumes are stored in one storage container. A method has been developed to reduce space, and in this case, the number of compressed items stored in the storage container is automatically controlled so that the amount of radiation leaking from the storage container and the total weight of the storage container are below the limit values. A volume reduction treatment method for limiting is also known from Japanese Patent Application Laid-Open No. 15600/1983.

However, in the volume reduction method described above, the compressed items are stored in storage containers in the same order, and the number of compressed items stored is limited so that the radiation dose, total weight, etc. do not exceed the limit values. Because of this, there is a possibility that there will be many storage containers with space left at the top, and compressed materials with a relatively high radiation dose may be stored at the top, so the amount of radiation leaking to the outside can be kept to a minimum. However, there was something unsatisfactory from the viewpoint of wanting to achieve closest packing.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems and is capable of filling a compressed material into a storage container in the most efficient manner while keeping the radiation dose and weight below the limit values. It was completed with the aim of creating a filling and processing method for radioactive waste that can be used to store radioactive waste.

(Means for solving the problem) The present invention measures the weight, radiation dose, and volume after pressure 11 volume reduction treatment of a container filled with radioactive waste, and inputs each measured value into a storage/arithmetic device. At the same time, the compressed materials are temporarily stored in a storage area where they can be sorted and taken out, and the combination of multiple compressed materials that has the maximum weight, maximum radiation dose, and maximum storage capacity that does not exceed the limit values is calculated, and the combined multiple compressed materials are The method is characterized in that the compressed materials with a relatively high radiation dose are surrounded by the compressed materials with a low radiation dose in the storage container while being sorted from the storage field.

Next, the present invention will be explained in more detail with reference to the illustrated embodiments. +1) is a container such as a drum filled with radioactive waste, and for example, is a container such as a drum can filled with radioactive waste. After conducting an internal inspection to see if the radiation level is high, the weight is measured using a scale (3), and the amount of radiation leaking from the surface is measured using a radiation dose measuring device (4). Next, the container (1) filled with radioactive waste is subjected to a volume reduction process by a high compression press (5) to, for example, a volume of about 1/4, and is made into a compressed product (6). The capacity of each sample is measured, and the measured values of weight, radiation dose, and capacity after compression are input into a storage/arithmetic device such as a computer. Note that there is no problem in measuring the weight and radiation dose of the container (11) after the compression volume reduction treatment.The compressed material (6) on which each of these measurements has been performed is temporarily stored in a storage field (7) that can be sorted and taken out. On the other hand, in the storage/arithmetic unit, the maximum weight, maximum radiation dose, and maximum storage capacity are reached within the respective limit values of weight, radiation dose, and capacity.
21. Calculate possible combinations of multiple compressed objects (6). In addition, the limit value of weight is, for example, 50Q kg,
The limit value of the amount of d is 200 mR/hr. A plurality of compressed materials (6) combined as a result of calculation in this way are sorted by a transfer device (8) such as a handling robot installed on the ceiling of the storage area (7), and are also sorted into drums or the like. It is transferred to a storage container (9) and filled therein, but at this time, the storage/arithmetic device selects the compressed material (6) with a relatively high radiation dose among the plurality of selected compressed materials (6).
The order of filling is instructed to the transfer machine (8) so that the compressed material (6) with a relatively low radiation dose surrounds the compressed material (6) above and below. In this way, within each limit value, the maximum weight,
A nozzle (1
Cement is injected from o) to fill the gap between the storage container (9) and the compressed material (6) and the upper part of the compressed material (6). After that, the cement is cured and capped (12) on the storage container (9) by the capping machine (11).
After surface inspection, radiation dose measurement, weight measurement, etc., a label is attached with the number, weight, surface dose, treatment date, etc. In addition, the process from compression volume reduction treatment to filling into the storage container (9) is carried out under a hood (
15) is preferably carried out inside.

(Effects of the Invention) As is clear from the above description, the present invention inputs each measured value of the weight of a container filled with radioactive waste, the radiation dose, and the volume of compressed material into a storage/arithmetic device, and stores the measured values. Maximum weight within a range that does not exceed the limit value in the computing device,
The combination of compressed materials is calculated to achieve the maximum radiation dose and maximum storage capacity, and based on this calculation, the compressed materials are selected from the storage field and filled into the storage container. Compared to the method of filling compressed materials that have been compressed and reduced in volume into storage containers in the same order as they are, and limiting the number of pieces so as not to exceed the limits for radiation dose and weight, Higher filling efficiency can be obtained, which is significant in making effective use of storage space for radioactive waste. Moreover, since the sorted compressed materials are filled into storage containers in the order in which compressed materials with a relatively high radiation dose are surrounded from above and below with compressed materials with a low radiation dose, the amount of radiation leaking from the storage container to the outside is reduced. The radiation dose is lower than that in the case where the top part is filled with a compressed material with a high radiation dose, and safety can be further improved than before.

Therefore, the present invention greatly contributes to the development of industry as a method for filling radioactive waste that is more efficient than conventional methods.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing the entire process of an embodiment of the present invention, and FIG. 2 is a block diagram for explaining the process. (1): Container, (6): Compressed material, (7): Storage field, (9
): Storage container.

Claims (1)

[Claims] 1. It is possible to measure the weight, radiation dose, and volume after compression and volume reduction of a container filled with radioactive waste, input each measured value into a storage and calculation device, and selectively take out the compressed material. Temporarily store the compressed materials in a storage field, calculate the combination of multiple compressed materials that has the maximum weight, maximum radiation dose, and maximum storage capacity that do not exceed the limit values, and sort out the combined compressed materials from the storage field. 1. A method for filling and processing radioactive waste, comprising filling a storage container in the order of surrounding a compressed material with a relatively high radiation dose with a compressed material with a low radiation dose. 2. Set the weight limit to 500kg and the radiation dose limit to 2.
The method for filling and treating radioactive waste according to claim 1, wherein the rate is 00 mR/hr. 3. The method for filling and treating radioactive waste according to claim 1 or 2, wherein both the container and the storage container are drums.