JPS61215996A - Decay heat removing emergency cooling device for fast breeder 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] [Industrial Application Field] The present invention relates to a cooling device for removing decay heat in a liquid metal cooled fast breeder reactor. [Prior Art] Liquid sodium or the like is used as a coolant. As shown in FIG. 2, a fast breeder reactor plant with loop liquid metal cooling using a The heated primary coolant 53 is passed through the primary main circulation pump 54 to the intermediate heat exchanger 5.
5, and a secondary main circulation pump 56 that circulates the secondary coolant that has been heated and heated by the intermediate heat exchanger 55.
A secondary main cooling system that circulates to the steam generator 57 by
and a water/steam system that supplies steam generated by the steam generator 57 to a power generation plant 58 to generate electricity. Further, as cooling systems for removing decay heat in this fast breeder reactor plant, for example, a direct core cooling system and an auxiliary core cooling system are provided. The direct core cooling system connects a heat exchanger 59 immersed in a primary coolant 53 in a reactor vessel 51 to an air cooler 61 with a stack 60;
Decay heat generated within the reactor vessel 51 is transferred to an air cooler 61.
The reactor core 52 is cooled by air cooling. Further, as an example of an auxiliary core cooling system, the steam output system on the output side of the steam generator 57 is branched off and connected to an air cooler 63 provided with a stack 62 . The decay heat generated in the reactor vessel 51 in this way is converted into steam by the primary main cooling system and the secondary main cooling system, and this steam is air-cooled by the air cooler 63 to cool the reactor core 52. I'm trying to cool it down.

In addition, the coolant purification system of the reactor primary system is cold trap 6.
4 and an electromagnetic pump 65, the electromagnetic pump 65
to suck the primary coolant 53 in the reactor vessel 51,
A cold trap 64 is used to remove impurities from the coolant.0 Figure 3 shows the cooling system of the ex-core fuel storage tank. A heat exchanger 74 immersed in a coolant 73 is connected to an air cooler 76 with a stack 75 to form an extra-core fuel storage tank cooling system, fuel 72
The decay heat generated by the fuel 72 is cooled by the air cooler 76, thereby cooling the fuel 72. The coolant purification system of the ex-core fuel cooling system is formed by a cold trap 77 and an electromagnetic pump 78.
The coolant 73 in the coolant 1 is sucked, and impurities in the coolant are removed in a cold trap 77.

[Problem that the invention seeks to solve]

As mentioned above, in order to remove decay heat from the core, fast breeder reactors are provided with a plurality of cooling systems, such as a direct core cooling system and an auxiliary core cooling system. This means that when the core temperature rises due to decay heat and there is a risk of fuel overheating, the decay heat removal system is designed to have redundancy and variety in order to safely and reliably remove this decay heat and prevent accidents. This is because sexuality is required. For this purpose, it is necessary to install a large number of cooling systems and to improve the design quality of equipment such as heat exchangers and piping materials, resulting in a problem that the equipment becomes complex and expensive.

The present invention was made in view of the above problems, and aims at increasing the redundancy and diversity of the decay heat removal system by sharing the cooling system of the ex-core fuel storage tank, thereby improving the reliability of decay heat removal. [Means for Solving Problems] The present invention provides a primary main cooling system that circulates primary coolant in a reactor vessel to an intermediate heat exchanger by a main circulation pump, and A fast breeder reactor equipped with a coolant purification system that circulates water to a cold trap using an electromagnetic pump; An ex-core fuel storage system comprising: an ex-core fuel storage tank cooling system that circulates coolant between an air cooler and a coolant purification system that circulates coolant to a cold trap using an electromagnetic pump; a cold trap connected to the coolant purification system of the breeder reactor;
It is characterized in that the inlet and outlet sides of the cold trap connected to the coolant purification system of the ex-core fuel storage device are connected by a coolant communication pipe.

[For production]

With the above structure, the decay heat generated within the reactor vessel is cooled down by a normal heat removal system or a decay heat removal system. In the event that the above-mentioned normal removal system cannot be used, the primary coolant is transferred from the reactor vessel to the ex-core fuel storage tank via a connecting pipe, and the coolant is transferred between the reactor vessel and the ex-core fuel storage tank. It is cooled by the external fuel storage tank cooling system while circulating between the

〔Example〕

An embodiment of the present invention will be explained with reference to the equipment connection diagram shown in FIG. 15 is the main cooling system of the fast breeder reactor, and the reactor vessel 1
A reactor core section 2 for heating a primary coolant 3 is installed inside the reactor. A primary cooling system that circulates heated primary coolant 3 to an intermediate heat exchanger 5 via a primary main circulation bomb 4 is connected to the reactor vessel 1.
, the secondary coolant whose temperature has been raised by receiving heat is transferred to the secondary main circulation pump 6.
A secondary cooling system is connected to the steam generator 7 by means of a secondary cooling system. Further, a water/steam system is connected to the steam generator 7 to feed the generated steam to the generator 8. 9 is a heat exchanger of the direct core cooling system, which is immersed in the primary coolant 3, is connected to the air cooler J1 equipped with the stack 10, and has a heat exchanger between the heat exchanger 9 and the air cooler 11. Cold coolant is allowed to circulate. 12 is a cold trap, and an electromagnetic pump 13 is connected in series to form a coolant purification system of the reactor primary system. 16 is an ex-core fuel storage device, and the used fuel 2 is stored in the ex-core fuel storage tank 21.
2 is stored immersed in a coolant 23. 24 is a heat exchanger of the outside fuel storage tank cooling system, which is immersed in the coolant 23, and an air cooler 2 equipped with a stack 25.
6, and a coolant for cooling is circulated between the heat exchanger 24 and the air cooler 26.

27 is a cold trap, and an electromagnetic pump 28 is connected in series to form a coolant purification system of the extra-core fuel cooling system.

As described above, the inlet/outlet side of the cold trap 12 connected to the coolant purification system of the reactor primary system of the fast breeder reactor 15, which has been grooved at the bottom, is connected to the coolant purification system of the ex-core fuel storage device 116. The inlet and outlet sides of the cold trap 27 are connected through coolant communication pipes 29a and 29b, respectively, and valves 30a and 30 are installed in the middle of the communication pipes 29a and 29b.
b.

In addition, the above-mentioned primary coolant and secondary coolant. A liquid metal coolant such as liquid sodium is used as a coolant for cooling.

Next, the function of this cooling system will be explained. Decay heat generated in the reactor vessel 1 is removed by a normal heat removal system using a primary cooling system, a direct core cooling system which is a decay heat removal system, etc. In the unlikely event that the above-mentioned removal system cannot be used or the heat removal is insufficient, the valves 30a and 30b are opened and the electromagnetic pumps 13 and 28 are operated to remove the primary coolant, which has been heated by decay heat. 3 is transferred from the reactor vessel 1 to the ex-core fuel storage tank 21 through the coolant communication pipes 29a and 29b, and at the same time, the coolant 23 in the ex-core fuel storage tank 21 is sent back to the reactor vessel 1 to perform the primary cooling operation 3. and the coolant 23 are mutually circulated. In this way, the inside of the reactor vessel 1 is cooled, and the coolant 23 whose temperature has increased is cooled by the external storage tank cooling system.

As described above, decay heat is now air-cooled by the direct core cooling system and the ex-core fuel storage tank cooling system, and these decay heat removal systems are mutually independent and have sufficient diversity. It is designed to have a

[Effects of the Invention] As explained above, conventional decay heat removal has multiplicity and diversity in the number of removal systems, heat removal capacity, and heat removal methods, such as direct core cooling system and auxiliary core cooling system. However, in the present invention, a simple means of connecting the reactor coolant purification system and the purification system of the external storage tank with a coolant communication pipe is used to solve the problem. The decay heat inside the reactor vessel can be cooled using the cooling system of the fuel storage tank outside the reactor, increasing the redundancy and diversity of the decay heat removal system at low cost and improving the reliability of decay heat removal. It's something that will improve it.

[Brief explanation of the drawing]

FIG. 1 is an equipment connection diagram of an embodiment of the present invention, FIG. 2 is an equipment connection diagram of a conventional fast breeder reactor, and FIG. 3 is an equipment connection diagram of a conventional ex-core fuel storage device.

Claims (1)

[Claims] A fast breeder reactor equipped with a primary main cooling system that circulates the primary coolant in the reactor vessel to an intermediate heat exchanger by a main circulation pump, and a coolant purification system that circulates the primary coolant to a cold trap by an electromagnetic pump; , an ex-core fuel storage tank cooling system that circulates coolant between a heat exchanger and an air cooler immersed in a coolant in an ex-core fuel storage tank attached to the reactor vessel; and a coolant. an inlet of the cold trap connected to each coolant purification system of the fast breeder reactor and the ex-core fuel storage system; A decay heat removal emergency cooling system for a fast breeder reactor, characterized in that the side and outlet sides are connected by coolant communication pipes.