JP2001033591A - Heat-generating body storage facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress building concrete below a limit temperature without forming side wall path and laying insulator in a cell chamber. SOLUTION: In a concrete cell chamber 3, a multitude of containing pipes 4 are arranged and a heat-generating body is contained in each containing pipe 4. The cell chamber 3 is partitioned by a partitioning wall 21 into an upper level side cell chamber 3a and a lower level side cell chamber 3b. In each chamber, upper plenum parts 10a and 10b and lower plenum parts 11a and 11b are formed. For every cell chamber part 3a and 3b, suction paths 13a and 13b to the lower plenum parts 11a and 11b are formed around the cell chamber 3. In the middle of the cell chamber 3, exhaust paths 12a and 12b from the upper plenum parts 10a and 10b are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for storing a vitrified body obtained by vitrifying radioactive waste liquid or a heating element that generates decay heat such as spent fuel sealed in a storage container for a long period of time. The present invention relates to a heating element storage facility used for the above.

[0002]

2. Description of the Related Art Radioactive liquid waste discharged from a nuclear power plant is permitted to be treated in the same manner as general industrial waste if the residual radioactivity is less than the specified discharge value. In the case of high-level radioactive liquid waste containing metals with strong radioactivity such as strontium, repeated natural decay occurs as a vitrified material that is vitrified so that the radioactive liquid waste is contained in glass crystals. It must be stored strictly for a long time in the required storage area until the radioactivity level drops. Further, the spent fuel also needs to be stored in a storage container similarly.

[0003] As an example of a vitrified storage facility conventionally proposed for storing a vitrified product obtained by vitrifying the above high-level radioactive liquid waste for a long period of time, one shown in FIG. 2 is shown. is there. That is, a cell room 3 is constructed just below the transfer chamber 2 for handling the vitrified material 1 using a crane and is surrounded by a thick concrete shielding wall as a storage area for the vitrified material 1. A large number of cylindrical storage tubes 4 for storing the vitrified body 1 as a heating element inside 3 are supported by opening the upper end thereof and hanging from the ceiling slab 5 at required intervals. After a large number of vitrified bodies 1 are stored in a stacked state from above in the storage tubes 4, the storage tube plugs 6 are packed in the upper ends of the storage tubes 4, and the upper end openings are closed with the storage tube lids 7. Thus, the vitrified body 1 is sealed in the storage tube 4, and each storage tube 4 in the cell chamber 3 passes through the outer periphery of the vitrified body storage portion as the heating element storage portion. The trachea 8 is arranged concentrically and the storage tube
And a stainless steel side wall channel formed on the inner wall 4 of the cell 3 and the upper end of each of the ventilation pipes 8 adjacent to each other. The upper plenum forming plate 16 closes the gap between the upper and lower forming plenums 15 to form the upper plenum section 10 above the flow passages 9. Is closed by a lower plenum forming plate 17 to form a lower plenum section 11 below the flow path 9. Further, the upper plenum section 10 has a cell chamber 3 having an upper end open to the atmosphere.
A lower end of an exhaust passage 12 formed on one side of an outer wall portion of the cell chamber 3 communicates with the lower plenum portion 11, and an intake passage formed on the other side of the outer wall portion of the cell chamber 3 so that the upper end is open to the atmosphere. 13 is communicated with the lower end of the lower plenum 11 from the atmosphere through the intake passage 13, and the cooling air 14 is drawn into the lower plenum 11 through the exhaust passage 12 to flow out of the passage 9 to the upper plenum 10 by natural convection. The vitrified body 1 in the storage tube 4 is cooled by air cooling.

Further, since the cooling air 14 after removing the decay heat of the vitrified body 1 has a high temperature, the inner wall of the cell chamber 3 serving as a storage section of the vitrified body 1 is protected to protect the building concrete. In the portion, the side wall flow path 18 having a required gap is formed by the side wall flow path forming plate 15 and the cooling air 1 is formed.
4 passes upward through the side wall flow path 18, and together with the hot cooling air 14 in the upper plenum 10, the exhaust passage 1
In addition, a heat insulating material 19 a is provided on the inner surface of the ceiling slab 5, and a heat insulating material 19 b is provided on the inner wall of the exhaust passage 12. In the drawing, reference numeral 20 denotes a maze plate provided in the intake passage 13 and the exhaust passage 12.

[0005]

However, in the case of the above-mentioned conventional vitrified storage facility, during the long-term storage of the vitrified material 1, the temperature of the cooling air 14 exceeds the limit temperature (65 ° C.) of the building concrete. Despite being temporary (several years), the formation of the side wall flow path 18 and the installation of the heat insulating materials 19a and 19b are required to protect the building concrete, and this is a factor that increases the equipment cost.

In view of the above, the present invention provides a facility for storing a heating element such as a vitrified body, in which the cooling of the heating element storage portion can be effectively performed, and the formation of the side wall flow path and the installation of a heat insulating material. It is intended to be able to keep the building concrete below the limit temperature without causing any problems.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention arranges a large number of vitrified bodies obtained by vitrifying radioactive waste liquid or heating elements such as spent fuel in a concrete cell chamber. The storage pipes are housed in the storage pipes, and a ventilation pipe is arranged around the outer circumference of each storage pipe to form an annular flow path. A heating element storage facility in which a plenum portion is formed, and cooling air introduced into the lower plenum portion through the intake passage portion is caused to flow out to the upper plenum portion through the flow passage, and then discharged through the exhaust passage portion. In the above, the cell chamber is vertically divided by a partition wall to form a plurality of cell chamber sections, and a portion of each storage pipe penetrating the partition wall is formed as a single pipe, and a flow path by a ventilation pipe is provided for each cell chamber section. Top and bottom respectively A plurality of intake passages for introducing cooling air to the lower plenums of the respective cell chambers are formed in an intake passage provided around the cell chambers; An exhaust passage from the upper plenum for each cell chamber is formed at the center of the cell chamber.

[0008] The cooling air is guided to the lower plenums of the cell chambers of the respective stages through the respective intake passages formed around the cell chambers, and formed into annular flows formed on the outer periphery of the storage tubes. After flowing upward through the passage, the heating element storage part of each storage pipe located in each cell chamber is cooled, and then discharged to a separate exhaust passage through the upper plenum to the atmosphere. Released. Therefore, a large amount of cooling air can be taken into each of the cell chambers from a wide outside area, and this cooling air comes into contact with only a part of the heating element housing portion. The temperature of the cooling air can be kept lower than the limit temperature of the building concrete.

[0009] Further, by forming each cell chamber portion into left and right portions such that the upper plenum portion communicates with the respective exhaust passage portions in the central portion, cooling is effected in the left and right compartment regions of each cell chamber portion. Since the air can be separately taken in, the heating element housing portion of each storage tube can be effectively cooled in a stable flow of the cooling air.

[0010]

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

FIGS. 1 (a) and 1 (b) show an embodiment of the present invention. In a structure similar to that shown in FIG. 2, a concrete partition wall 21 is provided at an intermediate position in the cell chamber 3 in the vertical direction. Is provided in a horizontal state, and the upper cell chamber portion 3a and the lower cell chamber portion 3b are formed by partitioning the partition wall 21 as a boundary. It is removed over a required length to form a single tube, and an intermediate portion in the vertical direction of each storage tube 4 is made to pass through a through hole provided in the partition wall 21 so that the upper cell chamber portion 3a and the lower cell chamber portion 3b Each time, an upper plenum portion 10a, 10b and a lower plenum portion 11a, 11b are formed in an upper portion and a lower portion of the flow path 9 formed by the storage pipe 4 and the ventilation pipe 8, respectively.

An intake passage 13 extending vertically and surrounding the cell chamber 3 is formed on each of the front, rear, left, and right sides outside the cell chamber 3 so as to be divided for each side. 13 is provided with an air inlet 24 so as to open the upper end to the atmosphere;
In each of the intake passages 13, a partition wall 22 for dividing the inside of the intake passage 13 inward and outward is provided so as to have a length extending from the air inlet 24 at the upper end to the lower plenum portion 11a of the upper cell chamber 3a. , Each air intake 24 of each intake passage 13
The inner intake passage 13a communicating with the upper side cell chamber 3
a, the cooling air 14 is communicated with the lower plenum 11b of the lower cell chamber 3b, and the cooling air 14 is communicated with the lower plenum 11a of the lower cell chamber 3b.
a, 13b to the upper and lower cell chambers 3a, 3b, respectively, while the upper cell chamber 3 is located at a position from the center of the ceiling slab 5 of the cell chamber 3 to the upper surface of the building.
Exhaust passage 12a communicating with upper plenum 10a
And an opening 23 is provided in the center of the partition wall 21, and an exhaust duct 12b having an exhaust duct 25 at the upper end above the opening 23 so as to enter the exhaust passage 12a. Is provided so as to communicate with the upper plenum portion 10b of the lower cell chamber portion 3b, and an exhaust duct 26 is connected to the upper end of the exhaust passage portion 12a. The upper and lower cell chamber portions 3a and 3b By the cooling air 14 taken in separately, the vitrified body storage portion as the heating body storage portion of each storage tube 4 can be separately cooled in two upper and lower stages.

The exhaust passage section 12b is formed by a hollow partition wall 27 extending in the front-rear direction and penetrating in the vertical direction, and divides the interior of the upper cell chamber section 3a into left and right sections. A partition wall 28 extending in the front-rear direction and having a height at which a required space is formed between the partition wall 21 and the partition wall 21 is provided on the bottom surface of the central part in the left-right direction in the lower cell chamber 3b. The inside of the section 3b is divided into left and right sections.

The same parts as those in FIG. 2 are denoted by the same reference numerals.

The cooling air 14 is supplied to the partition 2 by natural convection.
After being separately guided to the lower plenum portion 11a of the upper cell chamber portion 3a and the lower plenum portion 11b of the lower cell chamber portion 3b through the intake passage portions 13a and 13b partitioned by the respective sections 2, each cell chamber portion 3a , 3b, flows upward through the flow path 9 on the outer periphery of each storage tube 4, thereby uniformly cooling the vitrified material 1 sealed in the storage tube 4 and energy released from the vitrified material 1. Plenum part 1 while absorbing water
0a, 10b, and further into the upper plenum 10
The cooling air 14 that has reached the positions a and 10b is discharged to the atmosphere by the exhaust ducts 25 and 26 through the exhaust passages 12a and 12b at the center.

In the above, the intake passage sections 13a, 13b
Is formed over a wide area around the cell chamber 3 so that a large amount of cooling air 14 can be taken into each of the cell chamber sections 3a and 3b, and the storage chambers extending in the vertical direction in the cell chamber sections 3a and 3b. The upper and lower halves of the vitrified body storage portion of the tube 4 can be cooled separately. At this time, the cooling air 14
The vitrified body 1 is cooled by each of the cell chambers 3a, 3b.
Are performed separately in the left and right compartments formed by the compartment walls 27, 28, so that the vitrified material 1 in each storage tube 4 can be effectively cooled in a stable flow of the cooling air 14. it can. Therefore, even if the cooling air 14 absorbs the heat energy released from the vitrified body 1, the cooling air 14 cools the entire region of the vitrified body storage portion extending in the vertical direction as compared with the conventional facility shown in FIG. The temperature of the cooling air discharged from the upper plenums 10a, 10b of the upper and lower cell chambers 3a, 3b can be suppressed to a low temperature, and the building concrete can be maintained at a temperature lower than the limit temperature. . Therefore, as in the conventional equipment, the cell chamber 3 is provided with the side wall flow path and the heat insulating material 19a,
It is no longer necessary to install the heat insulating material 19b on the inner wall.

The present invention is not limited to the above embodiment. For example, FIG. 1 shows a case where the cell chamber 3 is divided into two upper and lower cell chambers 3a and 3b. In the embodiment, each of the cell chambers 3a and 3b can be divided into upper sections.
0a, 10b are the respective exhaust passage portions 12a, 12a,
Although the case where the partition walls 27 and 28 are divided into left and right so as to communicate with 12b is shown, it is not always necessary to partition left and right, and furthermore, the middle of the intake passages 13a and 13b and the exhaust passages 12a and 12b. It is optional to attach a maze plate in the middle, and in the embodiment, the vitrified storage facility is shown, but the same can be applied to the spent fuel storage facility, and other ranges that do not depart from the gist of the present invention It is needless to say that various changes can be made within.

[0018]

As described above, according to the heating element storage facility of the present invention, a large number of heating elements such as vitrified bodies or spent fuel obtained by vitrifying radioactive waste liquid are arranged in a concrete cell chamber. Stored in the storage pipes, and a ventilation pipe is arranged on the outer periphery of each storage pipe to form an annular flow path,
An upper plenum section is formed above the flow path, and a lower plenum section is formed below the flow path, and cooling air introduced through the intake passage section to the lower plenum section is passed through the upper flow path through the flow path. In the heating element storage facility, which is discharged through the exhaust passage after being discharged into the exhaust chamber, the cell chamber is vertically divided by a partition wall to form a plurality of cell chamber sections, and penetrates the partition wall. An upper plenum section and a lower plenum section are formed above and below the flow path formed by the ventilation pipe for each cell chamber section, and the lower plenum section is cooled for each cell chamber section. Each intake passage for introducing air is divided and formed in an intake passage provided around the cell chamber, and an exhaust passage from the upper plenum for each cell chamber is formed in the center of the cell chamber. Because it is a configuration that was A large amount of cooling air can be separately taken into the cell chamber on the side, and only the heating element housing portion located in the cell chamber on each side can be cooled. As well as being able to keep the temperature low, the heating element storage part can be cooled uniformly,
As in the past, as a protection measure for building concrete, it is possible to suppress the building concrete below the limit temperature without forming a side wall flow path in the cell room or installing heat insulating material in the cell room or the exhaust passage, Large capacity storage is possible by forming the cell chambers in multiple stages, and each cell chamber is divided into left and right so that the upper plenum communicates with the respective exhaust passages in the center. By
Cooling air can be separately taken into the left and right compartments of each cell chamber, and the heating element storage portion of each storage tube can be effectively cooled in a stable flow. Demonstrate.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a heating element storage facility according to the present invention, in which (a) is a schematic diagram of a vitrified object storage device,
(B) is an AA direction arrow view of (A).

FIG. 2 is a schematic diagram showing an example of a conventional vitrified material storage facility.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vitrified body (heat generating body) 3 Cell chamber 3a Upper cell chamber part 3b Lower cell chamber part 4 Storage pipe 8 Ventilation pipe 9 Flow path 10, 10a, 10b Upper plenum part 11, 11a, 11b Lower plenum part 12 Exhaust Passage 12a, 12b Exhaust passage 13 Intake passage 13a, 13b Intake passage 21 Partition wall

Claims (2)

[Claims] 1. Heating elements such as vitrified waste fuel or spent fuel obtained by vitrifying radioactive waste liquid are housed in a plurality of storage tubes arranged in a concrete cell chamber, and are passed through the outer peripheral portion of each storage tube. A trachea is arranged to form an annular flow passage, and an upper plenum portion is formed above the flow passage, and a lower plenum portion is formed below the flow passage, and an intake passage is passed through the lower plenum portion. After the introduced cooling air flows out to the upper plenum through the flow path, in the heating element storage facility which is discharged through the exhaust passage, the cell chamber is partitioned up and down by a partition wall to form a plurality of cells. The upper plenum section and the lower plenum section are formed above and below the flow path formed by the ventilation pipe for each cell chamber section, with each storage pipe section being formed in a chamber section and each storage pipe section penetrating the partition wall as a single pipe. And for each cell chamber Each intake passage section for introducing cooling air into the lower plenum section is formed by partitioning it into an intake passage provided around the cell chamber, and an exhaust passage section from the upper plenum section for each cell chamber section is formed as a cell chamber. A heating element storage facility characterized by having a configuration formed at the center of the heating element. 2. The heating element storage facility according to claim 1, wherein each of the cell chambers is divided into right and left such that an upper plenum communicates with a respective exhaust passage at a center.