JP2915469B2 - Liquid metal cooled reactor cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention] (Industrial application field) The present invention relates to a cooling system for a liquid metal cooled reactor,
The present invention relates to a cooling device for a secondary cooling system installed outside a reactor vessel.

(Prior Art) A conventional cooling device for a liquid metal cooled fast breeder reactor will be described with reference to FIG. That is, in FIG. 4, reference numeral 1 denotes a reactor vessel of a fast breeder reactor, in which a reactor core 2, a liquid metal sodium coolant (hereinafter, referred to as liquid) 3, and a primary main circulation pump are provided. 4 and an intermediate heat exchanger 5 are accommodated. The primary cooling system includes the liquid 3, the primary main circulation pump 4, and the intermediate heat exchanger 5. The secondary cooling system of the reactor includes an intermediate heat exchanger 5,
The steam generator 6 includes a steam generator 6 provided outside the reactor vessel 1, and a hot-leg pipe 8 and a cold-leg pipe 9, which are provided through a reactor building wall 7 to connect these two devices.

In the upper part of the main body 10 of the steam generator 6, a liquid inlet pipe 11 is provided.
On the other hand, a metal rising pipe 12 having an opening at the lower part of the main body 10 is disposed along the central axis of the main body 10,
A liquid outlet pipe 13 is connected to an upper end of the riser pipe 12. A space above the liquid level around the upper part of the riser 12
14 is provided with an electromagnetic pump 15.

FIG. 5 is a longitudinal sectional view showing the detailed structure of the steam generator 6 provided in the reactor secondary cooling system on the left half side. That is, the steam generator 6 has a main body
Supported through 18. Further, the riser tube 12 is disposed at a central portion in the main body 10, a heat transfer tube shroud 19 is disposed outside the riser tube 12, and a number of heat transfer tubes 20 are disposed in an annular space outside the heat transfer tube shroud 19. ing.

Incidentally, a free liquid surface 21 of the liquid is formed inside the upper part of the main body 10, and the space 14 above the free liquid surface 21 is
Absorbs volume changes due to thermal expansion of liquids.

On the other hand, a water inlet pipe 22 into which water supplied from a water supply pump flows, a header 23, and a distribution pipe 24
The water supply inlet section is constituted by the water chamber 25 and the water chamber 25 as shown in FIG. An outlet steam chamber 26, an outlet steam distribution pipe 27, an outlet steam header 28, and an outlet steam pipe
29 and 29 constitute a steam outlet portion.

FIG. 6 is a top view of the steam generator 6 in FIG. That is, the inlet pipe 11 is branched into two lines,
The outlet pipe 13 is provided at an upper portion of the main body 10, and is led out from the center of the top of the main body 10.

FIG. 7 is a longitudinal sectional view showing the inside of the top of the steam generator 6 in FIG. 5, and an electromagnetic pump 15 is provided on the inner circumference of the enlarged portion at the upper part of the riser 12. This electromagnetic pump 15 has an inner iron core 30
And a two-stator coil system in which an inner electromagnetic coil group 33 and an outer electromagnetic coil group 34 are wound inside and outside an annular flow path 32 formed annularly between the outer core 31 and the outer core 31. A magnetic field is generated by an electric current from a power supply to circulate the liquid.

The riser pipe 12 containing the electromagnetic pump 15 is connected to an outlet pipe 13, and the outlet pipe 13 is connected to a cold leg pipe 9.

The cooling device configured as described above operates as follows.

Heat is transmitted to the secondary cooling system via the intermediate heat exchanger 5 by circulating the primary coolant 3 for cooling the heat generated in the core 2 by the primary main circulation pump 4. On the other hand, the liquid of the secondary coolant is circulated by the electromagnetic pump 15 built in the steam generator 6, and the high-temperature liquid metal absorbed by the intermediate heat exchanger 5 passes through the hot leg pipe 8, passes through the inlet pipe 11, It flows into the generator 6.

Then, the high-temperature liquid gives heat so as to turn the supply water into steam while flowing down the outside of the heat transfer tube 20, and the temperature of the liquid itself decreases to become a low-temperature liquid. The low-temperature liquid rises in a riser pipe 12 which is opened and connected at a lower part in the steam generator 6, and is further provided with a discharge pressure by an electromagnetic pump 15, and then passes through an outlet pipe 13 and a cold leg pipe 9. It is returned to the intermediate heat exchanger 5.

On the other hand, on the water / steam side, feed water fed from a feed pump (not shown) flows into the header 23 from the water inlet pipe 22, is distributed in the flow rate by the distribution pipe 24, and is divided into a plurality of water streams in the water chamber 25. Reach. The feedwater distributed from the water chamber 25 to the inside of the heat transfer tube 20 is heat-exchanged with a liquid while rising inside the heat transfer tube 20, the temperature rises to steam, and then reaches the outlet steam chamber 26. Then, after passing through the outlet steam distribution pipe 27 and merging at the outlet steam header 28, it flows out of the outlet steam pipe 29 and is sent to a steam turbine (not shown).

(Problems to be Solved by the Invention) According to the conventional cooling device, when the electromagnetic pump 1 in the steam generator 6 breaks down, when the electromagnetic pump 15 is pulled out for replacement or repair, the outlet piping is required. There was a problem that 13 had to be cut and pulled out.

The present invention has been conceived to solve the above-described problems, and has an object to provide a cooling device for a liquid metal-cooled reactor that enables extraction of an electromagnetic pump without cutting an outlet pipe. I do.

[Configuration of the invention]

(Means for Solving the Problems) In the cooling apparatus for a liquid metal reactor according to the present invention, an electromagnetic pump installation flange at an upper portion of a steam generator is extended upward, and an outlet pipe is provided at a side surface of an electromagnetic pump supporting casing at a lower portion of the installation flange. To join. In addition, a liquid metal discharge port is provided on a side surface of a hanging casing that contains liquid metal discharged from the electromagnetic pump suspended by the installation flange, at a position facing the steam generator outlet pipe connection portion.

(Operation) In the present invention, after the liquid metal discharged from the electromagnetic pump enters the suspension casing that suspends the electromagnetic pump, the liquid metal is discharged from the discharge port provided on the side surface of the suspension casing, and the steam generator is discharged. It exits through a liquid metal outlet pipe connected to the upper electromagnetic pump support casing.

The liquid metal leaked from the gap between the electromagnetic pump hanging casing and the electromagnetic pump supporting casing descends through the gap and returns to the electromagnetic pump suction port.

Therefore, the liquid metal outlet pipe and the electromagnetic pump do not have a directly connected portion, and can be withdrawn without cutting the pipe when the electromagnetic pump is withdrawn.

(Example) Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a steam generator according to the present invention, and FIG. 2 shows an enlarged view of the electromagnetic pump section.

1 and 2, the same parts as those of the conventional example shown in FIGS. 4 to 7 are denoted by the same reference numerals, and the description of the configuration of the overlapping parts will be omitted.

In FIG. 1, an electromagnetic pump 15 is supported by an electromagnetic pump suspension casing 51 from an electromagnetic pump supporting casing 50 and is installed in a riser pipe 12.

Further, the outlet pipe 13 is welded to the supporting casing 50 and is not connected to the electromagnetic pump hanging casing 51.

At the electromagnetic pump outlet, an outlet pipe 13 and a supporting casing
A guide tube 52 routed at a position where the guide tube 52 is connected to the guide tube 50 is provided.

The riser tube 12 is a double tube in order to prevent heat exchange between the liquid metal inside and outside the riser tube, and has a gas space 33 such as an argon gas inside.

FIG. 2 is a cross-sectional view showing a detailed structure of the electromagnetic pump. A guide pipe 52 is connected to an outlet of the electromagnetic pump 15 and a discharge port 53 provided on a side surface of the electromagnetic pump hanging casing 51. To continue. However, hanging casing
The 51 and the guide tube 52 are not fixed by welding. At the connection between the outlet pipe 13 and the electromagnetic pump supporting casing 50, a discharge port 54 on the casing side is provided. A lid 55 is provided on the upper part of the electromagnetic pump, and is fixed to the suspension flange 56 by a bolt (not shown).

 Next, the operation of the above embodiment will be described.

The liquid metal discharged from the electromagnetic pump 15 passes through the guide pipe 52 to the discharge port 53 and suppresses a rapid change in the flow direction, so that the pressure loss is reduced and the liquid metal flows toward the discharge port 53.

Further, since the guide tube 52 is not connected to the electromagnetic pump hanging casing 51, it can freely move upward due to thermal expansion.

Further, the inside of the electromagnetic pump suspension casing 51 is filled with liquid metal. Since the outlet pipe 13 and the electromagnetic pump suspension casing 51 are not welded, the liquid metal leaking into the gap between the electromagnetic pump supporting casing and the electromagnetic pump suspending casing 51 descends,
It returns to the suction side 15 and is discharged again by the electromagnetic pump.

The electromagnetic pump support casing 50 and the suspension flange
The joint portion with 56 and the joint portion between the lid 55 and the suspension flange 56 are used in a normal liquid metal valve or the like to seal the liquid metal. It is connected by an Omega seal or the like.

With the above configuration, the electromagnetic pump 15 can send the liquid metal out of the steam generator without being directly connected to the outlet pipe 13, and the electromagnetic pump 15 can be removed only by removing the omega seal or the like of the suspension flange. It becomes possible to pull out without cutting the pipe.

Also, by flowing the liquid metal between the electromagnetic pump supporting casing and the electromagnetic pump hanging casing,
The heat generated by the electromagnetic pump can be recovered and the electromagnetic pump can be cooled.

 FIG. 3 shows a second embodiment according to the present invention.

In the second embodiment, a guide tube 52 and a discharge port 53 provided in a suspension casing 51 of an electromagnetic pump are hermetically connected by bellows 57, and the other components are the same as those in the above-described embodiment.

According to this configuration, even if the guide pipe 52 and the electromagnetic pump hanging casing 51 are relatively displaced in the vertical direction due to thermal expansion, they are absorbed by the bellows, and the liquid metal discharged from the electromagnetic pump is placed in the electromagnetic pump hanging casing. Without leaking
It can be sent from the discharge ports 53 and 54 to the outlet pipe.

Therefore, the liquid metal beam is not included in the suspension casing of the electromagnetic pump, and the seal between the lid 55 and the suspension flange 56 can be performed only by an O-ring or the like, similarly to the seal for a normal gas.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to pull out an electromagnetic pump without cutting | disconnecting piping at the time of a failure, etc., and can obtain the cooling apparatus of a liquid metal reactor with good repairability.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a cooling apparatus for a liquid metal reactor according to a first embodiment of the present invention, FIG. 2 is an enlarged view of a main part of FIG.
FIG. 4 is an enlarged view showing a second embodiment of the present invention, FIG. 4 is a system diagram showing a connection relationship with a steam generator used in a cooling device of a liquid metal reactor, and FIG. 5 is a liquid metal reactor. FIG. 6 is a top view of FIG. 5, and FIG. 7 is an enlarged sectional view of a main part of FIG. 6 ... Steam generator, 12 ... Rise pipe 11 ... Inlet pipe, 13 ... Outlet pipe 15 ... Electromagnetic pump 50 ... Electromagnetic pump supporting casing 51 ... Electromagnetic pump hanging casing 52 ... Guide pipe, 53 ... Discharge port 57 ... Bellows

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G21C 1/00 G21C 15/247 G21D 1/00 G21D 1/04

Claims (1)

(57) [Claims] 1. A cooling system for a liquid metal-cooled reactor, comprising a pipe connection between an intermediate heat exchanger disposed in a reactor vessel and a steam generator disposed in the reactor vessel. A liquid metal inlet distribution pipe provided at an upper part of a main body of the generator, a liquid metal outlet riser provided at a substantially central portion of the main body of the steam generator, and a liquid metal outlet riser provided inside the liquid metal outlet riser. An electromagnetic pump suspending cylindrical portion in which an electromagnetic pump is disposed, a guide tube provided inside the electromagnetic pump suspending cylindrical portion and having one end connected to a discharge port of the electromagnetic pump, and a liquid metal outlet rising An electromagnetic pump supporting cylindrical portion that is connected to a pipe and protrudes above the main body of the steam generator to support the electromagnetic pump hanging cylindrical portion; and the liquid metal that is connected to a side surface of the electromagnetic pump supporting cylindrical portion. Heat exchange from inlet piping An outlet pipe through which the liquid metal flows out, and an opening at the other end of the guide pipe is provided at a position where the outlet pipe is provided so as to face the liquid metal so that the liquid metal can flow out. Metal-cooled reactor cooling system.