JPH02210294A - Double tank type nuclear reactor structure - Google Patents

Abstract

PURPOSE:To reduce the external size of a nuclear reactor container, i.e. secondary container and to make the nuclear reactor structure compact by installing a spent fuel storage tank on the side of the secondary container. CONSTITUTION:The spent fuel storage tank 16 and other equipments are installed in the gap part between the secondary container 9 and a primary container 1. A rack 29 and a shaft 28 fitted in its center are provided in the storage tank 16 and a driving mechanism 27 is coupled with the shaft 28 and arranged on the top surface of a lid 20. Spent fuel which is reduced in decay heat by being stored in the storage tank 16 for a certain period is lifted into a fuel conveyance cell 21 through a fuel entrance/exit hole 19, stored, and moved to a disposal place. Thus, the diameter of the primary container 1 can be reduced by the radial size of the storage tank 16. The influence upon the diameter size of the secondary container 9 as a result of providing the storage tank 16 is small because the circumference-directional arrangement of equipments to be stored in the secondary container 9 has a margin. Therefore, the diameter of the nuclear reactor container, i.e. secondary container 9 is reducible.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) ゛The present invention is a double-tank atom system in which both the primary system and secondary system of a liquid metal cooled fast breeder reactor are housed in a tank. Regarding furnace structure.

(Prior art) The reactor structure concept of a liquid-cooled fast breeder reactor is the primary system and the secondary system.
A double tank type is known in which the secondary system is housed within the tank. In other words, the reactor core, intermediate heat exchanger,
It has a structure in which a primary coolant circulation pump, etc. is housed, and a steam generator, a secondary coolant circulation pump, etc. are housed in the outer secondary container. A conventional example will be explained with reference to FIG.

FIG. 4 is a vertical sectional view schematically showing a conventional example of a double tank type nuclear reactor structure.

A reactor core 2, an intermediate heat exchanger 3, and a primary sodium circulation pump 6 are arranged within the primary vessel 1, and a spent fuel storage layer 16 is provided around the reactor core 2.

A secondary container 9 is provided outside the primary container 1 so as to enclose the primary container 1, and the openings of both containers 1. ! 20 is installed. A secondary sodium circulation pump 10 and a steam generator 11 are housed in the gap between the secondary container 9 and the primary container 1.

A rotatable rotary plug 17 is mounted on the lid 20,
This rotating plug 17 is equipped with a fuel exchanger.

A fuel inlet/outlet hole 18 is formed in the lid 20 .

The intermediate heat exchanger 3 and the secondary sodium circulation pump 10 are connected by a secondary cold leg piping 30, and the intermediate heat exchanger 3 and the steam generator 3 are connected by a secondary hot leg piping 31.

High-temperature sodium flowing out of the reactor core 2 flows into the primary hot pool 7 and then into the intermediate heat exchanger 3 from the inlet of the intermediate heat exchanger 3. The primary sodium that has undergone heat exchange in the intermediate heat exchanger 3 flows into the primary cold pool 8,
After being sucked into the primary sodium circulation pump 6, it is pressurized and returned to the core 2.

The above flow is shown by the broken line arrow in FIG.

The secondary sodium whose temperature has been raised in the intermediate heat exchanger 3 flows into the steam generator 11, and after heat exchange, flows into the secondary sodium circulation pump 10, passes through the secondary system cold leg piping 30, and returns to the intermediate heat exchanger 3. Return to The above flow is shown by solid line arrows in FIG.

When exchanging fuel, the spent fuel in the core 2 is used by the fuel exchanger 4, positioned in the spent fuel storage tank 16 by rotation of the rotary plug 17, and then lowered there. The spent fuel, which has been stored for a certain period of time in the spent fuel storage tank 16 and whose decay heat has been reduced, is transferred by the fuel exchanger 4 and the rotary plug 17 to a position directly below the fuel inlet/outlet hole 18, and from there,
It is taken out of the lid 20. New fuel is loaded into the reactor core 2 in the reverse order.

(Problems to be Solved by the Invention) In the conventional example described above, inside the primary vessel 1, the core 2
A spent fuel storage tank 16 is provided outside the spent fuel as a storage space to reduce the decay heat of the spent fuel. The intermediate heat exchanger 3 and the primary sodium circulation pump 6 are arranged outside the steam spent fuel storage tank 16. Therefore, in the above equipment arrangement structure, there is a limit to the compactness of the reactor structure due to the radial equipment size restriction.

The present invention has been made based on the above-mentioned circumstances, and an object of the present invention is to obtain a double tank type nuclear reactor structure in which the reactor structure is made more compact.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a reactor core, an intermediate heat exchanger disposed around the core, and a primary sodium circulation pump.
A secondary container, a secondary sodium circulation pump and a steam generator disposed around the primary container, and a secondary container containing the primary container are connected to the upper end openings of the primary container and the secondary container. a rotary plug disposed in the center of the lid, a fuel exchanger penetrating the rotary plug and hanging above the reactor core, and a spent fuel storage layer provided in the secondary vessel. It is characterized by the following:

(Function) In the present invention, since the spent fuel storage tank is provided on the secondary container side, the diameter of the primary container can be reduced by the radial dimension of the spent fuel storage tank. Further, the influence on the diameter of the secondary container due to the provision of the spent fuel storage tank on the side of the secondary container is small because there is a margin in the circumferential arrangement of the equipment accommodated in the secondary container. Therefore, the diameter of the reactor vessel, that is, the diameter of the secondary vessel can be reduced in general.

(Example) An example of a double tank type nuclear reactor structure according to the present invention will be described with reference to FIGS. 1 and 2.

Note that FIG. 2 is a schematic longitudinal sectional view for explaining the fuel transfer state in FIG. 1.

In this embodiment, as shown in FIG.
A reactor core 2, an intermediate heat exchanger 3, a fuel exchanger 4, a direct core cooler 5, etc. are contained therein. A primary sodium circulation pump 6 is installed in series below the intermediate heat exchanger 3. A secondary container 9 is provided outside the primary container 1 so as to enclose the primary container 1 therein. These two containers 1.9
A holder 20 is attached to the upper opening of the holder. A secondary sodium circulation pump 10 is installed in the gap between the secondary container 9 and the primary container 1. A steam generator 11 and a spent fuel storage tank 16 are housed, and a secondary hot pool 13 and a secondary cold pool 14 are formed in the secondary container 9 by the partition wall 12 . Intermediate heat exchanger 3 and secondary heat exchanger ~ Lium circulation pump 10 is double pipe 1
Connected by 5. A rotatable rotary plug 17 is mounted on the lid 20, and the fuel exchanger 4 is mounted on this rotary plug 17. The lid 2G is provided with fuel inlet/outlet holes 18, 19 passing through it. A rack 29 and a shaft 28 attached to the center of the rack 29 are provided inside the spent fuel storage tank 16. A drive mechanism 27 is connected to this shaft 28 and mounted on the top surface of the lid 20 as shown in FIG.
is located.

High-temperature sodium flowing upward from the core 2 flows into the primary hot pool 7 and then into the intermediate heat exchanger 3 from the inlet of the intermediate heat exchanger 3. The primary sodium that has undergone heat exchange in the intermediate heat exchanger 3 is pressurized by the primary sodium circulation pump 6, flows out to the primary cold pool 8, and returns to the reactor core 2. The above flow is shown by the broken line arrows in FIG.

The secondary sodium pressurized by the secondary sodium circulation pump 10 flows into the intermediate heat exchanger 3 through the double pipe 15, and then passes through the double pipe 15 again after being heated to the secondary hot pool 13.
leaked to. After that, it flows into the steam generator 11, exchanges heat with water vapor, and flows out into the secondary cold boule 14.
Return to the secondary sodium circulation pump 10. The above flow is the first
This is indicated by the solid line arrow in the figure.

When exchanging fuel, the spent fuel in the core 2 is handled by the fuel exchanger 4, transferred to a position directly below the fuel inlet/outlet hole 18 by rotation of the rotary plug 17, and suspended. In this case, the fuel transfer cell 2 is placed above the ff120 as shown in FIG.
1 is placed on the floor 26.

A fuel transfer device 23 provided within the fuel transfer cell 21 descends through the guide tube 24, grabs the spent fuel, and lifts it into the fuel transfer cell 21. The fuel transfer machine 23, which is gripping the spent fuel along the rail 22, moves to a position directly above the fuel inlet/outlet hole 19, suspends the spent fuel there, and transfers the spent fuel to the guide tube 25. The spent fuel is loaded into a rack 29 in the spent fuel storage tank 16 through the fuel inlet/outlet hole 19. When the next spent fuel is transferred from the core 2 into the spent fuel storage tank 16, the shaft 28 is rotated by the drive mechanism 27, and the rack 29 is rotated to position it so that the spent fuel can be loaded. do. The spent fuel, which has been stored for a certain period of time in the spent fuel storage tank 16 and whose decay heat has been reduced, is lifted into the fuel transfer cell 21 from the fuel inlet/outlet hole 19 and stored (flame,
The spent fuel is stored in the fuel transfer cell 21 and moved to a spent fuel processing location. After the new fuel is moved from the new fuel storage location to the floor 26 while being stored in the fuel transfer cell 21,
The fuel is loaded into the core 2 through the guide tube 24 and the fuel inlet/outlet hole 18, and the fuel is transferred to the core 2 by the fuel exchanger 4 and the rotary plug 17.
Move to a predetermined position within 1. The flow of the transfer of spent fuel and new fuel during the above fuel exchange is shown in FIG. 2 by solid line arrows and broken line arrows, respectively.

FIG. 3 is a plan view showing another embodiment of the present invention, in which the same parts as those in FIG. This embodiment has a configuration in which four intermediate heat exchangers, four secondary sodium circulation pumps 10, and four steam generators 11 are incorporated. There are two spent fuel storage tanks 16.
It is arranged between the sodium circulation pumps 10 and 10. Therefore, by moving the spent fuel storage tank 16 arranged around the core 2 in the conventional example to the secondary container as in the example of the present invention, the diameter of the primary container 1 becomes correspondingly smaller.

Further, the reduction effect is also reflected on the secondary container 2.

[Effects of the Invention] According to the present invention, by installing the spent fuel storage tank on the side of the secondary vessel, the outer diameter of the reactor vessel that encloses the reactor structure, that is, the secondary vessel, can be reduced. The ability to make the reactor structure more compact will also lead to lower construction costs.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a double tank nuclear reactor structure according to the present invention, FIG. 2 is a vertical cross-sectional view for explaining the fuel transfer state in FIG. 1, and FIG. FIG. 4, a plan view showing another embodiment of the present invention, is a vertical sectional view of a conventional example. 1... Primary vessel 2... Core 3... Intermediate heat exchanger 4... Fuel exchanger 5... Direct core cooler 6... Primary sodium circulation pump 9... Secondary vessel 10...Secondary sodium circulation pump 11...Steam generator 15...Double pipe 16...Spent fuel storage tank 17...Rotary plug 20...Lid (8733) Agent Patent attorney Inomata Yoshiaki (baka)
1 person) Figure 7 Figure 2 Figure 3

Claims (1)

[Claims] A reactor core, a primary vessel containing an intermediate heat exchanger and a primary sodium circulation pump disposed around the core, a secondary sodium circulation pump and a steam generator disposed around the primary vessel, and the primary vessel. a secondary container containing the primary container and the secondary container, a lid connected to the upper end openings of the primary container and the secondary container, a rotary plug disposed in the center of the lid, and a rotary plug that passes through the rotary plug to open the core. A double tank nuclear reactor structure characterized by comprising a fuel exchanger hanging upward and a spent fuel storage layer provided in the secondary vessel.