JPH03102288A - Tank fast breeder - Google Patents

Abstract

PURPOSE:To contrive the improvement of earthquake resistance by fixing the upper end of a thin wall cylindrical vertical tube on a roof slab of a reactor vessel. CONSTITUTION:Each main circulation pump 4 is surrounded by a thin wall cylindrical vertical tube 13 over reactor tubing 12 from the upper part thereof and the lower end of the tube 13 penetrates a partition wall 9 to introduce in a cold pool 11 so that the inside of the tube 13 communicates with the inner space of a pool 11. In addition, the upper end of the tube 13 is fixed on a roof slab 17 to provide a plurality of flow holes so as to allow cover gas to flow on the upper part from a liquid surface of liquid metal 3. By such a structure vibration of the tube 13 can be controlled and the flow of the cover gas does not blocked since the flow holes are provided.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a tank-type fast breeder reactor whose interior is divided into a high-temperature pool and a low-temperature pool by partition walls and vertical pipes. Regarding fast breeder reactors that can be improved.

(Prior Art) An outline of a conventional tank-type fast breeder reactor will be explained with reference to FIG. That is, a reactor core 2 that generates thermal energy through a nuclear reaction is provided inside a main passenger unit 1 having a cylindrical shape with a bottom. Inside the main container 1, there are a plurality of main circulation pumps 4 that circulate liquid metal 3 (usually liquid sodium) as a primary coolant, and liquid metal (not shown, usually liquid sodium) as a secondary coolant from the primary coolant. ) accommodates primary cooling system equipment consisting of a plurality of intermediate heat exchangers 5 and the like for transmitting heat energy to the intermediate heat exchangers 5 and the like.

A core inlet plenum part 6 is provided at the bottom of the core 2 , and the core 2 and the core inlet plenum part 6 are supported by a core support 7 provided at the bottom of the main vessel 1 . A core upper mechanism 8 is disposed above the reactor core 2, and a partition wall 9 is disposed inside the main vessel 1.

The space inside the main container 1 is divided by the partition wall 9 into an upper hot pool 10 and a lower cold pool 11.

The plurality of main circulation pumps 4 and the plurality of intermediate heat exchangers 5
are arranged at equal intervals in the circumferential direction within the main container 1. A furnace pipe 12 is connected to the lower end of each main circulation pump 4, and the lower end of this furnace pipe 12 is connected to the cold pool 11.
It extends from the inside to the core inlet blenum section 6. A thin-walled cylindrical vertical pipe 13 extends from the bottom of each main circulation pump 4 to the furnace piping 12, and the lower end of the vertical pipe 13 is introduced into the cold pool 11 through the partition wall 9. The inside is communicated with the internal space of the cold boule 11.

A bottomed cylindrical safety container 14 is provided outside the main passenger unit 1 in case of a coolant leakage accident.

The fast breeder reactor configured as described above is supported by a cavity wall 16 of a reactor building via a support member 15 provided on the upper outer periphery.

The upper opening of the main container 1 is closed by a roof slap 17 forming an upper lid.

A cooling layer 18 is formed on the roof slab 17, and by circulating cooling gas through this cooling layer 18, the roof ●
This is to prevent the slap 17 from overheating. The hot pool 10 and the cold pool 11 contain liquid metal 3 (usually liquid sodium) as a primary coolant, and a cover gas is provided between the liquid level of the liquid metal 3 and the roof slap 17. is filled.

Next, the operation of a conventional tank-type fast breeder reactor will be explained.

First, while the liquid metal 3 serving as the primary coolant passes upward through the reactor core 2, it receives thermal energy from a nuclear reaction, becomes high in temperature, and flows into the hot pool 10. The high-temperature liquid metal then flows into the intermediate heat exchanger 5 from above, transfers thermal energy to the liquid metal as a secondary coolant, and flows down into the cold pool 11 while lowering the temperature. On the other hand, the liquid metal 3 in the cold pool 1 is pressurized by the main circulation pump 4 and passes through the reactor piping 12 to the core inlet plenum 6.
be returned to. In addition, the liquid metal as a secondary coolant heated by the intermediate heat exchanger 5 is led to the outside of the main passenger unit 1, and heats the steam for driving the turbine.

(Problems to be Solved by the Invention) In the conventional tank-type fast breeder reactor configured as described above, the upper end of the thin-walled cylindrical vertical pipe 13 is not fixed in a free state, so it is likely to vibrate during an earthquake. It has a structure. Therefore, there was a problem of poor earthquake resistance.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a fast breeder reactor with excellent earthquake resistance.

[Structure of the Invention] (Means for Solving the Problems) The present invention includes a reactor vessel in which a plurality of main circulation pumps and intermediate heat exchangers are housed, and a hot boule and a cold pool inside the reactor vessel. In a tank-type fast breeder reactor, the tank-type fast breeder reactor is equipped with a partition wall that partitions into a tank, and a thin-walled cylindrical vertical pipe that is connected to the partition wall and has an upper portion protruding above the liquid level of the reactor vessel, and that has the main circulation pump penetrated inside. , the thin-walled cylindrical vertical pipe is fixed to a loop slab of the reactor vessel, and a plurality of flow holes are provided on the inner and outer surfaces of the vertical pipe to allow flow of cover gas.

(Function) Because the upper end of the vertical pipe is fixed to the loop slab, it will vibrate during an earthquake and become difficult to install. Further, by providing the cover gas flow hole in the vertical pipe, the flow of gas inside and outside the vertical pipe is not obstructed.

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

In FIG. 1, a reactor core 2 that generates thermal energy through a nuclear reaction is provided inside a main vessel 1 having a cylindrical shape with a bottom. Inside the main passenger unit 1, there are a plurality of main circulation pumps 4 that circulate liquid metal 3 (usually liquid sodium) as a primary coolant, and a liquid metal (not shown) (usually A primary cooling system consisting of a plurality of intermediate heat exchangers 5 for transmitting heat energy to liquid sodium is housed.

The core 2 is supported by a core support 7 within the main passenger unit 1.

A core upper mechanism 8 is disposed above the core 2 .

A partition wall 9 is arranged inside the main passenger container 1, and this partition wall 9 allows the space inside the main passenger container 1 to be connected to the hot pool I above.
It is divided into a cold pool 11 and a lower cold pool 11.

The plurality of main circulation pumps 4 and the plurality of intermediate heat exchangers 5 are both arranged at equal intervals in the circumferential direction within the main passenger equipment 1. An in-furnace pipe 12 is connected to the lower end of each main circulation pump 3, and the lower end of this in-furnace pipe 12 extends to the reactor core in the cold pool 11.

A thin-walled cylindrical vertical pipe 13 extends from the bottom of each main circulation pump 4 to the furnace piping 12, and this vertical pipe 1
3 is introduced into the cold pool 11 through the partition wall 9, and the inside of the vertical pipe 13 is inserted into the cold pool 1.
1 is communicated with the internal space of the cold pool 11.

The upper end of the vertical pipe 13 is fixed to the roof slap 17 as shown in a partially enlarged view in FIG. A hole 19 is provided.

Further, a bottomed cylindrical safety container 14 is provided outside the main passenger equipment 1 in case of a coolant leakage accident.

By fixing the thin cylindrical vertical pipe 13 to the roof slab 17, vibration of the vertical pipe during an earthquake can be suppressed. Further, by providing the plurality of flow holes 19 above the liquid metal level, the flow of the cover gas is not obstructed.

[Effects of the Invention] According to the present invention, the earthquake resistance of a conventional tank-type fast breeder reactor can be improved without making any major structural changes.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing an embodiment of the fast breeder reactor according to the present invention, Fig. 2 is an elevational view showing an enlarged main part of Fig. 1, and Fig. 3 is a cross-sectional view showing a conventional fast breeder reactor. It is a diagram. 5... Support member 6... Cavity wall 7... Loop slab 8... Cooling layer 9... Flow port 1... Main vessel 2... Core 3... Liquid metal 4... Main circulation pump 5 Intermediate heat exchanger 6 Core inlet plenum 7 Core support 8 Core upper mechanism 9 Partition wall 10 Hot pool 11 Cold boule 12...Furnace piping 13...Vertical pipe 14...Safety container (8733) Agent Patent attorney Yoshiaki Inomata (and others)
1 person) 2nd country

Claims (1)

[Claims] A reactor vessel that houses a plurality of main circulation pumps and intermediate heat exchangers inside, a partition wall that divides the inside of the reactor vessel into a hot pool and a cold pool, and a partition wall that is connected to the partition wall and that connects the reactor vessel with a plurality of main circulation pumps and intermediate heat exchangers. In a tank-type fast breeder reactor equipped with a thin-walled cylindrical vertical pipe whose upper part protrudes above a surface and the main circulation pump penetrates inside, the thin-walled cylindrical vertical pipe is fixed to a loop slab of a reactor vessel. , and a plurality of flow holes are provided on the inner and outer surfaces of the vertical pipe to allow the flow of cover gas.