JPS61284695A - Tank type nuclear reactor - 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 [Technical Field of the Invention] The present invention relates to a tank-type nuclear reactor, and more particularly to a tank-type nuclear reactor in which a partition wall defining a hot pool and a shield boule inside a main vessel is improved.

[Technical background of the invention and its problems]

A conventional tank-type nuclear reactor is constructed as shown in FIG. That is, a main circulation pump 2 and an intermediate heat exchanger 3 are mounted on the roof slab 4 of the tank 1 so as to be housed within the tank 1, and the reactor core 5 is constructed as shown in the French Super Phoenix reactor. It is supported by a core lower support machine #16 that is directly fixed to the bottom of the tank 1. There is a high-pressure coolant brenum 7 between the core 5 and the lower core support mechanism 6, and the main circulation pump 2
A coolant discharge pipe 8 is connected thereto. The discharged coolant rises from the high-pressure brenum 7 while cooling the 5 parts of the reactor core, flows out into the hot pool 9, flows into the intermediate heat exchanger 3,
It flows out from the lower part of the intermediate heat exchanger 3 into the cold pool 10 and circulates inside the tank 1. Furthermore, an inner cylinder 11 is provided to cool the furnace wall of the tank 1.

Further, the lower end of the partition wall 12 that partitions the hot plate 9 and the coal boule 10 is fixed to the core lower support machine 16, and the upper end is not mechanically connected to the tank 1 etc. and is a free end.

Therefore, since the upper end of the partition wall 12 is not connected to the tank 1, its rigidity is weak, and its function as a seismic rest is small when an earthquake occurs, for example. That is, the bulkhead 12 does not function as a load transmission path from the reactor core 5 during an earthquake, and therefore, when seismic conditions are severe, the swing of the upper part of the reactor core 5 becomes large during a horizontal earthquake, and the control rod drive mechanism 13 in the upper part of the reactor There was a risk that it would be difficult to insert a control rod (not shown). Furthermore, since the only part connected to the tank 1 was the core lower support mechanism 6, a local load was applied to the tank 1, resulting in a large burden.

(Objective of the Invention) The present invention was made in view of the above circumstances, and an object of the present invention is to provide a tank-type nuclear reactor that ensures the stability of the reactor core during an earthquake and improves earthquake resistance. .

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention provides a tank-type nuclear reactor in which both a main circulation pump and an intermediate heat exchanger are built in a tank, in which the inside of the tank is divided into a hot pool and a cold pool. A partition wall passing through the main circulation pump and the intermediate heat exchanger has a toroidal structure and is connected to the tank, and a cooling path is provided around the toroidal structure to circulate the low-temperature coolant.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows the overall configuration of an embodiment of the present invention, in which a roof slab 21 that closes and closes the upper opening of a tank 20, which is a bottomed cylindrical body, has a roof slab 21 that is housed in the tank 20. A main circulation pump 22 and an intermediate heat exchanger (IHX) 23 are installed in the tank 20, and a core 26 is supported by a core support structure 25 provided above a lower plenum 24 at the bottom of the tank 20. Reaction control is performed by a control rod (not shown) that is inserted and withdrawn by a control rod drive machine M427 arranged in the control rod drive machine M427.

The upper part of the core 26 is a hot pool 2B, and the lower part on the side of the core 26 is a cold pool 29, which is divided by a partition wall 30. ,
Its outer periphery is coupled to the inner wall of tank 20. Therefore, this connecting portion 32 becomes a transmission path for imaging in the event of an earthquake, etc., and serves as a steady rest portion 31 that performs a steady rest function.

On the other hand, the main circulation pump 22 and the intermediate heat exchanger 23
As shown in the figure, a plurality of units, for example four units, are arranged in an annular manner in the tank 20 around the outer periphery of the core 26, and the lower portions of these units are convex above a partition wall 30 having a toroidal structure as shown in Figure 1. Each extends into the cold pool 29 by penetrating the arcuate top wall. This partition wall 30 has a pump stand vibe 33 on the outer periphery of each main circulation pump 22 and a seal vibe 3 on the outer periphery of each intermediate heat exchanger 23 in each penetration part.
4 are installed respectively.

A high-pressure coolant blemish 35 located above the lower blemish 24 is formed directly below the reactor core 26, and is connected to the main circulation pump 22 through a coolant discharge pipe 36, so that the main circulation pump 22 discharges the coolant. As shown by the thick arrow in FIG. 1, the coolant passes through the high-pressure blemish 35, rises while cooling the core 26, flows out into the hot pool 28, flows into the intermediate heat exchanger 23 from the upper part, and flows into the lower part of the intermediate heat exchanger 23. By flowing out into the cold pool 29, the water is circulated within the tank 20.

Furthermore, a cooling path 37 is provided around the joint 32 to circulate a low-temperature coolant. That is, lower Blenheim 2
An orifice 38 is provided between 4 and the high pressure blemish 25,
The lower blemish 24 and the cooling path 37 around the joint portion 32 are communicated with each other. Then, as shown by the small arrow in Figure 1,
The depressurized coolant leak flow flows from the high pressure blennium 35 to the lower blennium 24 through the orifice 38, and the pressure difference between the high pressure blennium 35 and the lower blennium 24 causes the low temperature coolant to flow from the lower blennium 24 to the cooling path 37. . By doing so, the tank 20 and the steady rest part 31 having the toroidal structure become the same temperature, and the thermal stress therebetween can be alleviated.

Note that the reference numeral 39 in the figure is a heat insulating structure provided on the upper part of the partition wall 30, and is intended to alleviate the influence of heat from the hot pool 28.

〔Effect of the invention〕

Therefore, in the present invention, since the core support structure and the tank wall are connected by the steady rest part having a toroidal structure, the steady rest part itself becomes a load transmission path, and the core support structure and the tank wall are connected to each other, so that the steady rest part itself becomes a load transmission path, and the core support structure and the tank wall are connected to each other by the steady rest part itself. The load burden on the joints with intermediate heat exchangers, etc. is reduced, and seismic resistance is improved, thereby ensuring ease of insertion of control rods into the reactor core in the event of an earthquake.

Furthermore, since it has a toroidal structure, the rigidity of the partition wall itself is high, and since not only the core support structure but also the steady rest are connected to the tank, it is possible to reduce the local load on the tank.

As explained above, according to the present invention, control rod insertability can be ensured and local loads on the tank can be reduced. This makes it possible to provide a simple means for stabilizing the core that meets the seismic conditions of Japan, where earthquakes occur frequently.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a sectional view taken along the Iru line in FIG. 1, and FIG. 3 is a sectional view of a conventional example. 20...tank, 21...roof slab, 22...
・Main circulation pump, 23... Intermediate heat exchanger, 24...
Lower blennium, 25... Core support structure, 26... Core, 27... Control rod drive mechanism, 28... Hot pool, 29... Cold pool, 30... Bulkhead, 31
... Steady rest part, 32... Joint part, 33... Pump stand vibe, 34... Intermediate heat exchanger seal pipe, 35... High pressure plenum, 36... Coolant discharge pipe, 37 ...cooling path, 38...orifice, 39.
...Insulated structure. ← Leak flow valve $ 1 time

Claims (1)

[Claims] 1. In a tank-type nuclear reactor in which both a main circulation pump and an intermediate heat exchanger are built in a tank, the inside of the tank is divided into a hot pool and a cold pool, and the main circulation pump and A tank-type nuclear reactor characterized in that a partition wall passing through the intermediate heat exchanger has a toroidal structure and is connected to the tank, and a cooling path is provided around the toroidal structure to circulate a low-temperature coolant. 2. The tank-type nuclear reactor according to claim 1, wherein the partition wall has an upper portion having a heat-insulating structure.