JPS60138301A - Steam generator 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] [Technical field of invention] The present invention relates to a steam generator for a fast breeder reactor.

[Technical background of the invention] In a fast breeder reactor that uses a liquid metal such as conodium as a primary coolant and a secondary cooling tank, the heat generated in the core is transferred to an intermediate heat exchanger via the primary coolant. A secondary coolant is used to transfer heat between the heat exchanger and the steam generator.

Figure 1 shows the schematic configuration of the secondary cooling Mj system and its i' station equipment of a conventional fast breeder reactor. J'3 is in heat exchanger 2 and transfers reactor raw heat to the secondary coolant.

The secondary cooling (l)trA superheated by this heat transfer passes through the bottom 1 to leg 3 and the hole 1 to leg stop valve 4) vessel 5
It is further introduced into the evaporator 7 from the swover pipe 6, generates superheated steam for driving the turbine, and after being cooled 7J1, it passes through the cold leg stop valve 8 and the expansion tank 9 to the circulation pump. 10, where it is again pressurized and introduced into the °C intermediate heat exchanger 2 through the cold leg 11.

The superheated steam generated by heat exchange with the secondary coolant breaks down to 1f.
As shown at A20, the water is introduced into the turbine 21, driven, and then condensed in the condenser 22, further heat-exchanged in the feed water heater 23, and then introduced into the circular evaporator 7.

An air cooler 30 is provided between the upstream side of the hot leg stop valve 4 and the expansion tank 9 so as to bypass the superheater 5 and the evaporator 7.

This air cooling system 3o constitutes an auxiliary core cooling system to avoid dissipating reactor decay heat.The secondary coolant flowing through a branch pipe 31 branched from the upstream side of the hot leg stop valve 4 is passed through a cooling blower 32. After being cooled by the air introduced into the c2 air cooler 30, the cold leg piping 33 and the cold leg regulating valve 3/I inserted in the cold leg piping 33 are sent into the light-C expansion tank 9.

The above-mentioned expansion tank 9 is used primarily to absorb and release the expansion and contraction of the secondary coolant. During this expansion, an overflow pipe 42 having an overflow control valve 41 and a suction pipe 44 having a suction pump 43 are connected between the tank and the tank 4°. Further, a cold leg pipe 35 on the outlet side of the expansion tank 9 and a drain pipe 46'r equipped with a drain valve 45 are connected between the OHALF [1 and the tank 40].

A-1 for storing liquid sodium is connected to OHALF 1-1-tank 4o via a communicating pipe-'133 equipped with a stop valve 47.
Bar 71-1 and tank 49 are connected. Na J3,
6 clothes tank 983 and Δ-bar flow tank 40.
An inert gas such as argon gas is sealed as a cover gas above the liquid surface of the 7.11 material in the cooling chamber 49, and is communicated by a piping system (not shown).

On the other hand, rupture discs 51a, 51, 52;
b is connected.

These rupture discs are installed in the superheater 5 or evaporator 7,
In the unlikely event that steam or water leaks and reacts with liquid sodium, which is the secondary coolant, the sodium-water reaction product acts as a safety valve to prevent the pressure horn in the secondary cooling system from reaching an abnormal value. , each rupture disc 31a, 31b, 52a
, 52b (1) The secondary side pipes are each connected to a reaction product storage tank 54 via a connecting pipe 53. Also,
At the upper end of the reaction product storage tank 54, there is provided an atmospheric release rupture plate 55, a check valve 56, and an igniter 5.
R58 is installed.

Figure 2 shows the steam generator 7 in Figure 1 (-as an example--C steamer)
It is a vertical cross-sectional view partially showing details of the side view C'.

Cold air 1 flows into the evaporator main body 7a from the upper distribution valve 60 and flows out from the d pipe 61 to an outlet provided at the lower part of the main body 7a. The water supply flows from the artificial part 62 installed in the lower part of the main body 7a, and heat exchange is performed by the heat exchanger tube 67 part.
A steam outlet is provided at the upper part of the water body 7a. Out]”, in 1” piping 6 of evaporator main body 7a
0.61 are each equipped with a rupture disc 52a1521], and are connected to the C reaction production storage tank 5 via the connecting pipe 53.
/I is connected.

As mentioned above, the secondary cooling system of the fast breeder reactor F7
During normal operation of the reactor, the secondary coolant circulated by the circulation pump 10 smells in the intermediate heat exchanger 2 (atomic 'y
After the heat generated by J'i is transferred, the heat is radiated to the superheater 5, the evaporator 7, and the evaporator 7, and the heat is transferred to the power generation equipment 1 including the turbine 21.

In such a state C1 superheater 5 or evaporator 7-r.
If a lium-water reaction occurs, the rupture discs 51a, 5
1b, 52a, or 52b ruptures, the reaction product passes through the connecting pipe 53 and reaches the C reaction product storage tank 54, where the separated gas ruptures the atmosphere release rupture plate 55 and causes the outside air to flow back. Flowing past the check valve 56 of the previous 1L river, the purple color (
After the scum components are ignited by the igniter 57t' and burned, they are released into the air.

``Problems with blue stone technology'' However, if steam or water leaks to the -LJ-shita steam generator, Rinawara superheater 5 or evaporator 7 to the ',ll-lium side, the sodium-lium-water reaction will occur. Yotsu C
The resulting reaction product gas causes a sudden increase in pressure, resulting in
Rupture 4N51a, 51b, 52a, 52- The 4Ns were destroyed and the reaction product moved to the reaction product storage tank 54 and covered it, but there was a drawback (see below) that it was blown away.

However, in conventional steam generators, the rupture disc is installed by branching into the inlet and outlet piping of the steam generator. Therefore, when a sodium-water reaction occurs in the steam generator, incompressible sodium is first released into large ml, and then the reaction product gas is first released from the steam generator to the reaction product storage tank 54 side. be done. This becomes a very big problem from the viewpoint of quickly reducing the pressure in the secondary system.

In other words, since the incompressible release of sodium does not significantly affect the pressure reduction in the secondary system, the pressure decreases slowly while sodium is released.

As a result, high pressure may propagate to other equipment and piping installed in the secondary system, resulting in damage to the equipment and piping, which is a major concern from the perspective of ensuring the safety of the reactor. This is a serious problem.

[Object of the Invention] The present invention has been made to eliminate the above-mentioned disadvantages caused by the back-tilting girder, and is aimed at eliminating sodium-
Even if a water reaction occurs and a high-pressure reaction product is produced, the high-pressure reaction product is quickly released into the reaction product storage tank]1
The present invention provides a steam generator for a fast breeder reactor that can be used in a fast breeder reactor.

[Summary of the Invention 1] That is, the present invention provides an internal shroud disposed in a steam generator main body, the upper and lower ends of which are formed into a hollow cylindrical container, and sodium inflow or outflow near the center of the internal shroud. This is a steam generator that has a large number of flow passage holes that allow for a rupture plate to be inserted in the upper part of the inner shroud, and a rupture disc inserted in the upper part or both parts of the inner shroud, and connected to connecting pipes. According to the present invention, J: the conventional steam generator C'
This solves a number of problematic points.

[Embodiments of the Invention] Each embodiment of the present invention will be explained below with reference to FIG. 3 (FIG. 15 and FIG. 4).

FIG. 3 shows a first embodiment of a steam generator according to the present invention. Parts that are the same as those in FIG.

The difference between FIG. 3 and FIG. 2 is that the upper part 80 and lower part 81 of the internal shroud 68 disposed in the main body 7 are closed, and the communication pipes 53a and 53b are connected to the walls of the upper part 80 and lower part 81, respectively. These connecting pipes 53a,
53b are provided with rupture discs 42a and 52b, respectively, and connected to the connecting pipe 53 shown in FIG. Rupture tube 42
a and 52b are provided through the upper end plate of the main body 7. Further, in the center of the inner shroud 68, there is provided a passage hole 70 for sodium passing through a large number of small holes.

FIG. 4 shows another embodiment of the present invention. Components that are the same as those in FIG.

The difference between FIG. 4 and FIG. 3 is that when a drain hole 72 is provided in the lower part 81 of the internal shroud 68,
a, 53b are led out from the lower side of the main body 7a, and -C rupture discs 52a, 52b are provided.

In FIGS. 3 and 4, reference numeral 60 is an inlet pipe connected to the steam generator main body 7a, and 61 is a sodium outlet pipe. The water system (from the water system -i~ flows in from the water supply pipe 62 in the opposite direction to the flow of lithium, and exchanges heat with the heat exchanger tube 67 part Ml-lium. (1) The steam flows out from the steam outlet pipe 63 and the steam flows into the turbine system. - As mentioned above, an internal shroud 6B is arranged at the center within the main body 7a, forming a hollow cylindrical container with an upper end and a lower end. The upper part 80 and the lower part 81 (,t, rupture disc 52a, 5
21+ is inserted, the connecting pipe 53a and 5311 are connected to Wt.
Near the center of the inner 81S shroud 68, there is a passage hole through which sodium can flow in and out.

- For some reason, the heat exchanger tube 67 broke 1 (4).
Water or steam leaks from Boo 1 to Boo 1-1.
When the nitrogen-water reaction occurs, the pressure inside the steam generator main body 7a becomes high due to the residue produced by the reaction, and as a result, either or both of the rupture discs 52a and 52b are violently destroyed. In addition, the high-pressure sodium-water reaction product gas generated in the steam generator passes through a flow path 70 provided in the center of the internal shroud 68 together with sodium, and directly flows into the reaction product storage tank 54. can be released to
It becomes possible to quickly reduce the pressure within the steam generator.

In addition, in the embodiment shown in FIG. 4, the function and effect explained in FIG. The structure is such that it is possible to drain the 1-lium.

``Effects of the Invention J'' As described above, according to the steam generator for a fast breeder reactor according to the present invention, the heat transfer tubes are damaged and high-pressure compressible reaction gas is generated due to the butryum-water reaction. It is also possible to immediately release the reaction product into the storage tank, and as a result, the amount of heat in the secondary system can be quickly and safely reduced. Therefore, it is possible not only to prevent the influence on the next system (shallow vessel A3 and piping), but also to contribute to the safety of the reactor J3 and the improvement of the operation rate, which has a great effect on the economy.

[Brief explanation of drawings]

Fig. 1 is a system diagram schematically showing the secondary system of a conventional fast breeder reactor, Fig. 2 is a vertical sectional view partially showing a conventional steam generator from the side, and Figs. 3 and 4 are the invention of the present invention. A partial side view of each embodiment of the hot air generator for high speed increase M'i
FIG. 1......-Next cooling N) system 2...
・・・・・・Intermediate heat exchanger 3・・・・・・・・・・・・
・Hot leg 4...Hot leg stop valve 5...Superheater 6...Crossover piping 7・・・
・・・・・・・・・Evaporator 8・・・・・・・・・・・・21-Ledreg stop valve 9...
・・・・・・・・・l1iQ Zhang tank 10・・・・
......Circulation pump 11...
・・・Cold leg 20・・・・・・・・・・・・Dotted line 21・・・・・・・・・Turbine 22・・・・・・
......Condenser 23...Feed water heater 30...
......Air cooler 31...
...Branch pipe 32... Cold h1 Zorua 33...
......Cold leg piping 3/l...
......Cold leg adjustment valve 40...
...Overflow [] - Tanks 52a, 52b - Rupture disc 53 ...... Connection piping 60 ...
......S1~Lium-filled piping 61...
...S1~Lium outlet piping 62...
...Water supply pipe 63...Steam outlet pipe 6/'I.
・・・・・・・・・h3 air outlet pipe stand 65・・・・・・
...Heat shield plate 66...Boo 1-Rium distribution plate 67...Heat transfer tube 68... ...Internal shroud 69...
・・・・・・・・・Water supply inlet pipe stand 70・・・・・・・
...Flow path hole 71...Natural air generator body 72...
......Sodium drain hole 80...
...Inner shroud upper part 81...
...Inner Shroud Lower Agent Patent Attorney Suyama In. Figure 2 Figure 3

Claims (2)

[Claims] (1) A cylindrical vertical body, a pair of sodium inlet and outlet pipes attached to the upper and lower ends of this body, and an interior arranged along the axis of the body and connected to both ends with connections and piping. A shroud, a sodium passage hole formed approximately at the center of the inner shroud, a rupture plate provided in the connecting pipe, and a rupture plate supported by the inner shroud and having a space on the inner surface of the main body. A steam generator for a fast breeder reactor, characterized in that it is equipped with a heat exchanger tube Iff surrounded by a closed outer shroud, a water supply J5 J: from which heated steam flows out of the nine heat exchanger tubes, and a steam outlet piping. vessel. (2) A steam generator for a fast breeder reactor according to claim 1r3, characterized in that a drain hole is formed in the bottom of the internal shroud.