JP2001183487A - Water filling facilities for reactor jessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide water filling facilities for a reactor versel enabling effective use of a cooling water source and the supply of a cooling water in a short time, without requiring an extra amount of water if by chance a large amount of cooling water is filled in the reactor vessel and the reactor container requires external cooling. SOLUTION: A forcibly closing function is provided for a vacuum bracker 29 provided in a vent pipe 28. Electrically stopped valves 19a, 19b are provided in an condensate storage tank normal/abnormal communication pipe 18 communicating between a condensate storage tank abnormal service pipe 20 and a condensate storage tank normal service pipe 20. When cooling water is filled in a dry well 26 for the reactor container 25, the electrically stopped valves 19a, 19b are opened and the vacuum breaker 29 is closed forcibly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water injection system in a nuclear power plant, and more particularly, to a reactor containment water injection system provided in case of a nuclear reactor accident.

[0002]

2. Description of the Related Art In a nuclear power plant using a boiling water reactor, an ECC is required in preparation for an emergency such as a coolant leak due to a break in a pipe connected to a reactor pressure vessel.
S (emergency core cooling system) is provided.

[0003] This ECCS is also called an emergency core cooling system, and is configured with a high-pressure core cooling system, an automatic decompression system, and a low-pressure core water injection mode which is one of the functions provided in the residual heat removal system. In the event of occurrence of an emergency, the reactor is shut down in an emergency, and the core is submerged by water injection from the ECCS so that the core is rapidly cooled.

FIG. 7 shows a containment vessel 2 according to the prior art.
5, the reactor containment vessel 25 is divided into an upper space and a lower space, and the upper space is a D / W (dry well) 26 in which the reactor pressure vessel 23 is accommodated. The space is a W / W (wet well) 27 and a pressure suppression chamber 30, and when the coolant flows out due to breakage of a pipe connected to the reactor pressure vessel 23, etc.
At the time of the emergency shutdown of the reactor, coolant was injected into the core 24
Is submerged so that the core 24 is cooled.

[0005] First, the high pressure core cooling system of the ECCS comprises a high pressure core cooling pump 32, a pipe 35, valves 33a and 3c.
3b, 34a, 34b, a strainer 31a, and the like. The water in the condensate storage tank 15 and the pool water in the pressure suppression chamber 30 are supplied to the high pressure core cooling pump suction valves 33a, 33b.
It is configured so that it can be used as a water source by opening and closing.

[0006] Next, when the pressure in the reactor pressure vessel 23 rises significantly, for example, when the high-pressure core cooling system is inoperable, the automatic steam release system opens the main steam release safety valve 37 to operate the residual heat removal system. It has a function of rapidly reducing the pressure to a pressure at which core injection can be performed in a low-pressure core injection mode, which is one of the modes.

In this low pressure core injection mode, the residual heat removal pump suction valve 39, the residual heat removal pump 38, the residual heat removal pipe 41, the heat exchanger 42, the heat exchanger switching valves 43a and 43b, the low pressure core injection from the strainer 31b. Valve 40a,
Devices up to 40b, a dry well spray valve 45, a wet well spray valve 47, a dry well spray header 46, and a wet well spray header 48 are used.

When cooling the reactor pressure vessel 23 in the low-pressure core injection mode, the pool water in the pressure suppression chamber 30 is used as a water source, and the reactor is pumped by the residual heat removal pump 38 via the low-pressure core injection valves 40a and 40b. Water is injected into the pressure vessel 23.

Next, the residual heat removal system includes the reactor containment vessel 2.
5 is provided in order to remove heat and suppress the rise in pressure and temperature of the reactor containment vessel 25. Therefore, the cooling water cooled by the heat exchanger 42 is supplied from the spray headers 46 and 48 to the D / W 26 and W / W27, and at this time, the heat exchanger 42 is
The cooling operation is performed by the cooling water sent in the step (1).

In such an emergency, the cooling water flowing out of the reactor pressure vessel 23 and the cooling water sprayed into the D / W 26 pass through the vent pipe 28 to the pressure suppression chamber 30.
After returning to the inside, it is stored as pool water and then used again as cooling water.

Here, the pressure in the D / W 26 is rapidly reduced by the D / W spray in the vent pipe 28, and the W / W2
A vacuum break valve 29A is provided as indicated by the dashed line A in case the pressure in 7 becomes higher than the pressure in D / W 26.

As shown in FIG. 8, the vacuum break valve 29A includes a valve body 1 and a flange plate 2 serving as a valve seat thereof, and the inside of the vent pipe 28 is set to a negative pressure with respect to the inside of the W / W 27. When this happens, the valve body 1 is automatically opened by this negative pressure, thereby allowing the D / W 26 to communicate with the W / W 27,
The pressure in / W27 is suppressed from becoming higher than the pressure in D / W26.

On the other hand, the vacuum break valve 29A is required to confirm its operation during a regular test. Therefore, as shown in FIG. 8, the valve body 1 and the flange plate 2 are further connected to the arm 3 And bearing 4, gas pressure cylinder 5, piston 6,
A test three-way solenoid valve 7, a test isolation solenoid valve 8, and a test nitrogen gas supply pipe 9 are provided.

Accordingly, the vacuum breaking valve 29A switches the open position of the test three-way solenoid valve 7 to supply nitrogen gas to the gas cylinder 5 so that the piston 6 of the gas cylinder 5 moves in the direction of the dashed arrow. Pushed down, arm 3
, The valve element 1 is moved in the direction of the dashed arrow, whereby the valve can be forcibly opened and it can be confirmed that the operation is possible.

FIG. 9 shows a test control logic of the vacuum break valve 29A, which is composed of a test switch and a control circuit as shown in the figure, and opens the vacuum break valve by turning on the test switch during a regular operation test. A signal is generated which allows an open test of the vacuum break valve to be performed. In the drawing, E represents the energization of the solenoid valve.

Further, in this prior art, a condensate make-up water system is provided as a system for sealing and cleaning pipes in a nuclear power plant, and the water in the condensate storage tank 15 is also used in this system. However, at this time, as described in JP-A-7-134194, the water in the condensate storage tank 15 is shared for regular use and emergency use.

Therefore, in order to prevent the water in the condensate storage tank 15 from being used all the time, the outlet pipe of the water source is connected to the condensate storage tank for taking out water from the bottom of the condensate storage tank 15. And a condensate storage tank for extracting water from the side (condensate make-up water system).

The condensate storage tank service / emergency communication pipe 18 and the condensate storage tank service / emergency communication pipe stop valve 49a, 4
9b, and by opening these valves 49a and 49b when necessary, the water at the bottom of the condensate storage tank 15 is supplied from the condensate storage tank emergency (high-pressure core cooling system) intake pipe 20 to the condensate make-up water system. As a result, the water at the bottom of the condensate storage tank 15 can be effectively used even during the periodic inspection of the plant.

Further, in this prior art, although the probability is extremely low, a severe accident in which the engineering safety facilities such as the ECCS cause multiple failures is assumed. To ensure safety, the condensate make-up water pump 16 and the condensate make-up water pipe 17, which are alternative facilities as the water injection equipment, the condensate storage tank regular (condensate make-up water system) draw-in pipe 21, and the residual heat removal system Communication valve 2
2a and 22b are provided, and water in the condensate storage tank 15 is supplied to the reactor pressure vessel 23 or the reactor containment vessel 25 via the residual heat removal system by the condensate makeup water system composed of these and the condensate storage tank 15. It is designed so that water can be injected inside.

Therefore, in the event of a severe accident, the condensate make-up water system can be used for cooling the reactor pressure vessel 23 as described below. That is, at the time of a severe accident, first, water is injected into the reactor pressure vessel 23 to maintain the soundness of the reactor pressure vessel 23. However, the ECCS does not operate properly due to multiple failures and the like. When there is no possibility, a large amount of water in the condensate storage tank 15 is injected into the reactor containment vessel 25 by the condensate make-up water pump 16, the reactor pressure vessel 23 is cooled from the outside, and The soundness of the furnace pressure vessel 23 is maintained.

This is discussed in the following article. “In-vessel retention of corium at the Loviisa pla
nt ”Nuclear Engineering and Design 169 (1997) 109-130

[0022]

In the above prior art, E
In response to severe accidents such as multiple failures of CCS, a large amount of water is supplied to the D / W from the condensate storage tank. At this time, since the vacuum release valve is provided in the vent pipe, the pressure suppression chamber is also required. Since water is injected, the amount of water required for cooling increases, and the rise of the water level in the D / W is delayed.

This will be described more specifically with reference to FIGS. 7 and 8. As described above, the inside of the vent pipe 28 has a W /
When a negative pressure is applied to the inside of the W27, the valve body 1 of the vacuum break valve 29 opens, so that the D / W26 and the W / W27 are communicated, and the pressure is equalized.

For this reason, even if the cooling water is supplied to the D / W 26, the supplied water remains in the D / W2 until the level of the pool water in the pressure suppression chamber 30 rises and the vacuum break valve 29 is submerged.
The cooling water cannot be stored in the D / W 26 during this time because the process shifts from 6 to the pressure suppression chamber 30 via the vent pipe 28.

For this reason, in the prior art, after water is injected into the D / W 26, an extra amount of water is required until the water level in the D / W 26 necessary for cooling the reactor pressure vessel 23 from the outside is secured. In addition, it takes extra time,
This causes the above problem. In addition, the amount of water injected from the outside is also limited in terms of the amount of water possessed by the plant, considering the water injection from the condensate supply water system in the event of a severe accident.

An object of the present invention is to make effective use of a cooling water source and to inject a large amount of cooling water into a reactor containment vessel,
Even if it becomes necessary to externally cool the reactor pressure vessel,
An object of the present invention is to provide a reactor containment water injection system capable of supplying water in a short time without requiring an extra amount of water.

[0027]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vacuum release valve which is divided into an upper space accommodating a reactor pressure vessel and a lower space serving as a pressure suppression chamber, and a vent pipe communicating the upper space and the lower space. In the water injection equipment for a reactor containment vessel provided with, a valve closing mechanism is provided for the vacuum break valve, and the valve opening mechanism can forcibly close the vacuum break valve when water is injected into the upper space. Is achieved.

At this time, the opening / closing mechanism may include a gas pressure cylinder for preventing operation of the vacuum breaking valve due to a pressure difference between the upper space and the lower space and closing the valve.

Further, the above-mentioned object is to provide an atomic reactor which is divided into an upper space accommodating a reactor pressure vessel and a lower space serving as a pressure suppression chamber, and which is provided with a vacuum break valve in a vent pipe connecting the upper space and the lower space. In the water injection system of the containment vessel,
A motor-operated valve is provided on the connecting pipe from the condensate storage tank emergency draw-in pipe of the high-pressure core cooling system to the regular draw-in pipe of the condensate make-up water system, and the motor-operated valve can be opened and controlled when water is injected into the upper space. This is also achieved in such a way.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A reactor containment water injection system according to the present invention will be described below in detail with reference to the illustrated embodiments. FIG. 1 shows a first embodiment of the present invention. In this embodiment, as shown in FIG.
Vacuum break valve 2 in the prior art described with reference to FIGS.
9A, only the condensate storage tank normal / emergency communication pipe stop valves 49a, 49b in the prior art of FIG. 9 are replaced by condensate storage tank normal / emergency communication pipe electric stop valves 19a, 19b. The rest of the configuration is the same as the conventional equipment described with reference to FIG.

Therefore, also in the embodiment of FIG. 1, the condensate storage tank 15, the condensate storage tank regular (condensate make-up water system) draw-in pipe 21, the condensate make-up water pump 16, the condensate make-up water pipe 17, the residual heat The point that a condensate makeup water system is constituted by the removal system communication valves 22a and 22b is the same as the prior art. In the event of a severe accident such as a multiple failure of the ECCS, water is taken in from the bottom of the condensate storage tank 15 and The same applies to the configuration in which water is injected into the D / W 26 of the storage container 25.

Next, the operation of this embodiment will be described. In the event of a severe accident such as multiple failures of the ECCS, the condensate storage tank regular / emergency communication pipe electric stop valves 19a and 19b are opened by remote control by an operator from the central control room, and the condensate make-up water pump 16 The condensate storage tank 15
Is taken out from the bottom of the reactor and injected into the D / W 26 of the containment vessel 25 via the residual heat removal system.

At the same time as the water injection operation of the D / W 26, control is performed so that the vacuum break valve 29 is maintained closed.
As a result, the D / W 26 and the W / W 27 are
To prevent the cooling water injected into the D / W 26 from flowing into the pressure suppression chamber 30 through the vent pipe 28, so that the injected cooling water accumulates only in the D / W 26. To

Therefore, according to this embodiment,
Even if it becomes necessary to externally cool the reactor pressure vessel,
Since there is no possibility of water being injected into an extra portion, the inside of the D / W 26 can be filled with cooling water with a minimum amount of water and a minimum time, and at this time, from the bottom of the condensate storage tank 15 Since the water is taken out, the cooling water source can be effectively used, and the water can be injected into the D / W 26 in the reactor pressure vessel in a short time.

For this reason, the vacuum break valve 29 in the embodiment of FIG. 1 is configured as shown in FIG. First, a valve body 1, a flange plate 2, an arm 3, a bearing 4, a pneumatic cylinder 5, a piston 6, a three-way solenoid valve 7 for testing, a isolation solenoid valve 8 for testing, and a nitrogen gas supply pipe 9 for testing are provided. This is the same as the vacuum break valve 29A in the prior art described with reference to FIG.

However, in the vacuum release valve 29 of this embodiment, the fluid pressure actuator composed of the gas pressure cylinder 5 and the piston 6 is of a double-acting type, and further provided with a nitrogen gas supply pipe 10 for forcibly closing and closing the vacuum release valve. It differs from the prior art vacuum break valve 29A in that a three-way solenoid valve 11 for use, an isolation solenoid valve 12 for closing and closing, an accumulator 13 for storing nitrogen gas for closing and closing, and a check valve 14 for accumulating nitrogen gas are provided. I have.

Accordingly, by switching the opening direction of the three-way solenoid valve for closing and closing 11 and supplying the nitrogen gas stored in the accumulator 13, the piston 6 of the gas pressure cylinder 5 is pushed up as shown by the solid line arrow. Is maintained, and even when the pressure P2 on the W / W 27 side in the reactor containment vessel 25 exceeds the pressure P1 on the D / W 26 side, the vacuum break valve 29 is forcibly closed so as not to open. Is available.

Here, the vacuum break valve 29 in this embodiment also switches the opening direction of the test three-way solenoid valve 7 to supply the nitrogen gas when performing the regular operation test, and supplies the gas as indicated by the dashed arrow. The open test can be performed by pushing down the piston 6 of the pressure cylinder 5. At this time, since the opening direction of the three-way solenoid valves 7 and 11 is switched to the atmosphere, the piston 6 in the gas pressure cylinder 5 is normally operated. Can be moved up and down free, so the basic vacuum breaking function is not impaired.

Next, the control logic (signal circuit) of the electric stop valves 19a and 19b and the vacuum break valve 29 according to this embodiment will be described with reference to FIG. The control logic shown in FIG. 3 is constituted by switches, relays, relay contacts, and the like. The control logic of the electric stop valves 19 a and 19 b is on the upper side, and the control logic of the vacuum break valve 29 is on the lower side. The electric stop valve 19
Since a and the electric stop valve 19b have the same control logic, only the control logic of one of the electric stop valves 19a and 19b is shown in the upper part of FIG.

First, the condensate storage tank service / emergency communication pipe electric stop valves 19a and 19b are controlled by an operator-operated condensate storage tank service / emergency communication pipe electric stop valve switch, as shown in the figure. Is done. However, at this time, the use of the cooling water in the condensate storage tank 15 as a water source of the ECCS is prioritized, and a function for assuring this is required. Therefore, when the ECCS start signal is generated, The opening and closing of the condensate storage tank regular / emergency communication pipe electric stop valve is prohibited.

That is, as an output signal for opening the condensate storage tank regular / emergency communication pipe electric stop valve, an ECCS start signal is output, and at this time, the ECCS start signal forced off switch is in the normal position. , And are supplied at a later stage. Note that in FIG.
(Wipeout) is a logic that inhibits the transmission of left-to-right signals when there is an input from above (prohibition logic)
Represents

Therefore, when the ECCS start signal is generated, the condensate storage tank normal / emergency communication pipe electric stop valve cannot be opened. However, in the event of a severe accident, the reactor containment vessel cannot be opened. Since the ECCS start signal may be generated in a state where water injection is required, in this case, the ECCS start signal is forcibly cut off by the operator's judgment so that the ECCS start signal can be cut off. Is forcibly WO and cut off.

As shown in the figure, the condensate storage tank normal / emergency communication pipe electric stop valve is controlled by self-holding logic by feeding back the output of WO logic to the input. A fully open valve input and a fully closed valve input for release are provided.

Next, the vacuum break valve 29 is
It is controlled by a vacuum break valve forced open switch operated by an operator. However, at this time, D / W26 and W / W
When a differential pressure is generated in the valve 27, the original function of the vacuum break valve for equalizing the pressure is given priority. Therefore, when the ECCS activation signal is generated, as a function to guarantee this, the vacuum break valve is forcibly closed. The signal output from the switch is configured to be transmitted to the subsequent stage on condition that the ECCS start signal due to the signal from the switch is not output, and at the same time, the output from the vacuum release valve test switch is W
It is configured to shut off O.

Next, FIG. 4 shows another embodiment of the control logic of the electric stop valves 19a and 19b and the vacuum break valve 29 for the condensate storage tank regular / emergency communication pipe. In the embodiment of FIG. EC for output signal of release valve forced closing switch
The inhibit logic by the CS start signal is changed from the AND circuit to W
Instead of O logic, other configurations are the same.

The control logic described with reference to FIGS. 3 and 4 is not limited to a hard wired / relay circuit, but may be an electronic circuit using an integrated circuit (IC) chip.

Next, FIG. 5 shows another embodiment of the present invention, which is different from the embodiment described in FIG. 1 in that a high-pressure nitrogen cylinder 50 is installed instead of the accumulator 13 in the embodiment of FIG. The nitrogen gas is supplied to the gas pressure cylinder 5 from now on. Note that air may be used instead of nitrogen.

Therefore, according to the embodiment of the present invention, since the vacuum break valve 29 provided in the vent pipe 28 can be forcibly maintained in the closed state, the pressure suppression chamber 3 can be maintained.
The water level of the pool water of 0 rises, and the same state as the state where the vacuum break valve is submerged can be forcibly made.

For this reason, when water is injected into the D / W 26, the flow of water into the pressure suppression chamber 30 is suppressed, and the injected cooling water can be concentrated on the D / W side from the beginning. The water injection time required before the vacuum break valve 29 is submerged is unnecessary, and the delay caused by the rise of the water level in the D / W can be shortened accordingly. As a result, severe accidents such as multiple failures of the ECCS can be performed in a short time. And high reliability can be easily maintained.

Further, since the flow of the cooling water into the pressure suppression chamber 30 is suppressed, the amount of water required for cooling the reactor pressure vessel 23 is reduced by that much, and the situation where the cooling water is insufficient is obtained. In this case, sufficient reliability can be easily obtained.

Further, in the event of a severe accident, the condensate storage tank regular / emergency communication pipes are operated by opening the electric stop valves 19a and 19b to take out water from the bottom of the condensate storage tank 15. Almost all of the water in the reactor 15 can be injected into the reactor containment vessel 25, and sufficient safety can be ensured by effectively utilizing the water possessed by the plant.

[0052]

According to the present invention, a sufficient amount of cooling water can be injected into the containment vessel in a short time without requiring an extra amount of water, so that the cooling water source can be used effectively. In the unlikely event that a large amount of cooling water is injected into the containment vessel,
Even if it becomes necessary to externally cool the reactor pressure vessel,
Sufficient measures can be taken.

Therefore, according to the present invention, severe accidents such as multiple ECCS failures can be sufficiently dealt with in a short time, and high reliability can be easily maintained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a reactor containment water injection system according to the present invention.

FIG. 2 is a detailed explanatory view showing an example of a vacuum break valve in one embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating an example of a control logic according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram showing another example of the control logic according to the embodiment of the present invention.

FIG. 5 is a block diagram showing another embodiment of a reactor containment water injection system according to the present invention.

FIG. 6 is a detailed explanatory view showing an example of a vacuum break valve in another embodiment of the present invention.

FIG. 7 is a block diagram showing an example of a conventional reactor containment water injection system.

FIG. 8 is a detailed explanatory view of a vacuum break valve according to an example of the related art.

FIG. 9 is an explanatory diagram of a control logic in an example of the related art.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Valve body 2 Flange plate 3 Arm 4 Bearing 5 Pneumatic cylinder 6 Piston 7 Three-way solenoid valve for test 8 Isolation solenoid valve for test 9 Nitrogen gas supply pipe for test 10 Vacuum break valve Nitrogen gas supply pipe for forced closing 11 Vacuum break Three-way solenoid valve for forced closing of valve 12 Isolation solenoid valve for forced closing of vacuum release valve 13 Accumulator for forced closing of vacuum release valve 14 Non-return valve for accumulator of nitrogen gas for accumulator for forced closing of vacuum 15 Condensate storage tank 16 Condensate refill water Pump 17 Condensate make-up water pipe 18 Condensate storage tank regular / emergency communication pipe 19 Condensate storage tank regular / emergency communication pipe Electric stop valve 20 Condensate storage tank emergency (high-pressure core cooling system) draw-in pipe 21 Condensate Storage tank regular use (condensate make-up water system) intake pipe 22 Residual heat removal system communication valve 23 Reactor pressure vessel 24 Reactor core 25 Atom Reactor containment vessel 26 Dry well (D / W) 27 Wet well (W / W) 28 Vent pipe 29 Vacuum break valve 30 Suppression chamber 31 Strainer 32 High pressure core cooling pump 33 High pressure core cooling pump suction valve 34 High pressure core cooling water injection valve 35 High-pressure core cooling pipe 36 Main steam pipe 37 Main steam relief safety valve 38 Residual heat removal pump 39 Residual heat removal pump suction valve 40 Low-pressure core injection valve 41 Residual heat removal pipe 42 Heat exchanger 43 Heat exchanger switching valve 44 Auxiliary equipment cooling Pump 45 Dry well spray valve 46 Dry well spray header 47 Wet well spray valve 48 Wet well spray header 49 Condensate storage tank regular / emergency communication pipe stop valve 50 High pressure nitrogen cylinder

Continued on the front page (72) Inventor Hiroshi Suzuki 3-18-1, Omikacho, Hitachi City, Ibaraki Prefecture Inside Ibaraki Hitachi Information Service Co., Ltd. (72) Inventor Shingo Oda 3-2-1 Sachimachi, Hitachi City, Ibaraki Prefecture Hitachi Engineering Co., Ltd. (72) Inventor Kohei Kumochi 3-1-1 Sachimachi, Hitachi City, Ibaraki Prefecture Inside the Nuclear Power Division, Hitachi, Ltd. (72) Inventor Koji Hashimoto 3-Chome, Sachimachi, Hitachi City, Ibaraki Prefecture No. 2 Hitachi Engineering Co., Ltd. (72) Inventor Hirokatsu Shishido 3-18-1, Omika-cho, Hitachi City, Ibaraki F-term in Ibaraki Hitachi Information Service Co., Ltd. 2G002 AA03 BA01 CA08 DA03 EA14

Claims (3)

[Claims] 1. An upper space containing a reactor pressure vessel,
In a water injection facility for a reactor containment vessel which is partitioned into lower spaces serving as pressure suppression chambers and has a vacuum break valve in a vent pipe communicating the upper space and the lower space, a valve closing mechanism is provided in the vacuum break valve, The reactor opening water injection equipment, wherein the valve opening mechanism is configured to forcibly close the vacuum break valve when water is injected into the upper space. 2. The invention according to claim 1, wherein the opening / closing mechanism includes a gas pressure cylinder for preventing operation of the vacuum break valve due to a pressure difference between the upper space and the lower space and closing the valve. A reactor containment water injection system, characterized in that: 3. An upper space containing a reactor pressure vessel,
Emergency withdrawal of condensate storage tank for high-pressure core cooling system in reactor containment water injection system, which is divided into a lower space that serves as a pressure suppression chamber and is equipped with a vacuum break valve in a vent pipe that connects the upper space and the lower space An electric valve is provided on a connecting pipe from a pipe to a regular drawing pipe of a condensate make-up water system, and the electric valve is configured to be capable of opening control when water is injected into the upper space. Furnace containment water injection equipment.