JPH0762715B2 - Emergency core cooling system - Google Patents

Description

TECHNICAL FIELD The present invention relates to an emergency core cooling device for a nuclear reactor, and more particularly to an emergency core cooling device having a high installation rate and a high effective head.

[Conventional technology]

In the conventional technique, as described in JP-A-259995, the water storage pool is a high pressure resistant container, the pressure container and the water storage pool are connected by a pressure equalizing pipe, and water is injected by steam pressurization and gravity. It was structured. In addition, as described in A.N.S. Transactions, 47 (1984), pages 292 to 293, a pressure suppression pool for condensing steam generated in the reactor is placed at a position sufficiently higher than the reactor. It was installed and constructed so that the water in the pressure suppression pool could be injected by gravity falling.

[Problems to be Solved by the Invention]

The above-mentioned conventional technology does not consider the point of improving the installation rate and effectively securing the effective head, and the installation rate is lowered or the effective head is secured because a high pressure resistant container is required. Therefore, the pressure suppression pool is installed at a position sufficiently higher than the reactor, which causes a problem that the seismic resistance decreases.

An object of the present invention is to provide an emergency core cooling device which can be installed at a low level position because the installation rate is improved by effectively utilizing the containment vessel wall and the effective head is high.

[Means for Solving the Problems]

The above-mentioned object is an emergency core cooling device for a reactor consisting of a device for injecting cooling water into the reactor and a pressure suppression pool for condensing steam generated in the reactor, and a water storage pool separate from the pressure suppression pool. Is installed, and a flow path and a valve are installed between the reactor and the upper space of the water storage pool and the water storage unit, and the upper space of the water storage pool and the water storage unit of the pressure suppression pool are pressure equalizing pipes. This is achieved by an emergency core cooling device characterized in that a part of the water storage pool wall is a containment vessel wall surrounding the reactor pressure vessel.

[Action]

The operation of the present invention will be described below. In the event of loss of reactor coolant due to breakage of piping etc., the automatic depressurization system operates and the steam generated in the reactor is led to the pressure suppression pool. In the present invention, when the water in the water storage pool is injected into the reactor, the valves installed between the reactor and the upper space of the water storage pool and the water storage unit are opened. As a result, a part of the steam generated in the reactor flows into the upper space of the water storage pool, and further flows through the pressure equalizing pipe into the water storage section of the pressure suppression pool to be condensed. Therefore, the pressure in the upper space of the water storage pool is higher than the pressure in the upper space of the pressure suppression pool, and is equivalent to the length of the pressure equalization pipe in the water storage part of the pressure suppression pool, and the local pressure at the inlet and outlet of the pressure equalization pipe. The total pressure loss and the friction loss in the pressure equalizing tube. This value is 1 atm or less in a normal design, and a part of the containment vessel wall can be used as a water storage pool wall, so that the installation rate can be improved. Further, the pressure of the upper space of the water storage pool in the present invention is the length of the pipe in the water storage portion of the water storage pool as compared with the conventional device that guides the steam into the water storage portion in order to condense the steam. The sum of the static head equivalent to the above and the blowout loss at the outlet of the pipe becomes higher. As a result, the effective head of the cooling water is increased and the water storage pool can be installed at a low level position, and the installation position improves the installation rate by sharing the containment vessel wall of the reactor. The effect of doing is obtained.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 5. The core 2 loaded in the pressure vessel 1 is surrounded by a shell 3. During normal operation, the steam generated in the core 2 is dehumidified by the dryer 4, and then the main steam pipe 5
Through a turbine system (not shown). The steam condensed in the turbine system is supplied to the pressure vessel 1 via the water supply pipe 6.
Return to the inside. Cooling water flows into the core 2 by natural circulation caused by the pressure difference between the inside and outside of the shroud 3, and the core 2 is cooled. In such a nuclear reactor, assuming a coolant loss accident due to breakage of piping, for example, the water supply piping 6, the cooling water in the pressure vessel 1 flows out and the water level decreases. When the water level is lower than the upper end of the shroud 3 by 3 m, for example, an automatic decompression system start signal is issued and after a certain time delay, for example 120 seconds, the automatic decompression system valve 10 and valve 11
Is released. As a result, a part of the steam generated in the core 2 flows from the valve 10 through the pipe 20 into the water storage portion of the pressure suppression pool 21 and is condensed, so that the pressure in the pressure vessel 1 rapidly decreases. Further, a part of the steam generated in the core 2 flows from the valve 11 through the pipe 30 into the upper space of the water storage pool 31.
The steam flowing into the upper space of the water storage pool 31 is further equalized
Through 32, it flows into the water storage section of the pressure suppression pool 21 and is condensed. When the pressure in the pressure vessel 1 becomes lower than the pressure in the pressure vessel 40, the cooling water in the pressure vessel 40 flows into the pressure vessel 1 through the pipe 41 and the check valve 42 for preventing the backflow from the pressure vessel 1. Then, the water level is maintained above the core 2. When the pressure in the pressure vessel 1 further decreases, the cooling water in the water storage pool 31 flows into the pressure vessel 1 through the check valve 34 that prevents the reverse flow from the pipe 33 and the pressure vessel 1 due to gravity, and the water level Are held above the core 2. The flow state at this time is shown in FIG. The pressure of the upper space of the water storage pool 31 in the present embodiment is higher than the pressure of the upper space of the pressure suppression pool 21, and the hydrostatic head corresponding to the length of the pressure equalization pipe 32 in the water storage portion of the pressure suppression pool 21, the pressure equalization pipe 32. Local pressure loss at the doorway of
And the friction loss in the pressure equalizing pipe 32, the higher the sum. In this embodiment, this value is 1 atm or less, and a part of the wall of the storage container 7 can be used as the wall of the water storage pool 31. FIG. 3 shows a sectional view taken along the line AA in FIG. The water storage pool 31 is the storage container 7
It is placed compactly by using the wall of, and the installation rate is improving. A mesh for preventing a person or equipment from falling is installed above the vent pipe 50 that guides the vapor discharged into the containment vessel 7. FIG. 4 shows changes over time in the pressure in the pressure vessel 1 and the flow rate of water injected into the pressure vessel 1 in a typical coolant loss accident, for example, a small breakage of the water supply pipe 6. The pressure in the upper space of the water storage pool 31 in the present embodiment is longer than that of a conventional device that guides steam into the water storage unit to condense the steam. The sum of the static head and the loss at the outlet of the pipe increases. Thereby, in this embodiment, the effective head for injecting the cooling water becomes high,
Even if the water storage pool 31 is installed at a low level position, a sufficient water injection flow rate can be obtained. The diameter of the pipe 33 is 0.1 m in this embodiment. Further, in this embodiment, since the water storage pool 31 is at the low level position, the earthquake resistance is good. The equalizing pipe 32
In order to make the inflow of steam smooth and to prevent the entrainment of the cooling water due to the fluctuation of the water surface, it is desirable that the upper part of the above has a structure that widens toward the upper end as shown in FIG.

According to the present embodiment, since the wall of the storage container can be effectively used, the installation rate is improved, and since the effective head is high, it can be installed at a low level position and the earthquake resistance is improved.

Another embodiment of the present invention will be described with reference to FIG. The difference from the embodiment shown in FIG. 1 is that the water storage pool 31 is installed above the pressure control pool 21. Further, the water storage pool 31 is compactly installed by utilizing the wall of the storage container 7 on the shoulder portion of the storage container 7 which has not been used so far. Further, inside the water storage pool 31, a heat shield plate 60 that protects the wall of the storage container 7 is provided. A reinforcement member 61 is provided below the water storage pool 31 to improve earthquake resistance. In such a nuclear reactor, assuming a coolant loss accident due to breakage of piping, for example, the water supply piping 6, the cooling water in the pressure vessel 1 flows out and the water level decreases. When the water level is lower than the upper end of the shroud 3 for 3m, the automatic decompression system start signal is issued, and after a certain time delay, for example 120 seconds, the automatic decompression system valves 10 and 11 are opened. It As a result, a part of the steam generated in the core 2 flows from the valve 10 through the pipe 20 into the water storage portion of the pressure suppression pool 21 and is condensed, so that the pressure in the pressure vessel 1 rapidly decreases. Also, core 2
Part of the steam generated in 1 flows into the upper space of the water storage pool 31 from the valve 11 through the pipe 30. At this time, since the heat shield plate 60 is provided, the inflowing steam does not directly hit the wall of the storage container 7. The steam flowing into the upper space of the water storage pool 31 further passes through the pressure equalizing pipe 32 and flows into the water storage portion of the pressure suppression pool 21 to be condensed. When the pressure in the pressure container 1 becomes lower than the pressure in the pressure accumulator container 40, the check valve for preventing the cooling water in the pressure accumulator container 40 from flowing back from the pipe 41 and the pressure container 1
It flows into the pressure vessel 1 through 42 and keeps the water level above the core 2. When the pressure inside the pressure vessel 1 further decreases,
The pressure vessel 1 passes through the check valve 34 that prevents the backflow of the cooling water in the water storage pool 31 from the piping 33 and the pressure vessel 1 due to gravity.
Flows inward and keeps the water level above the core 2. In this embodiment, since the height difference between the water storage pool 31 and the core 2 is large, the effective head is high, and the pipe 33 is thin, for example, 0.05 m, but a sufficient water injection flow rate can be obtained.

According to this embodiment, there is an effect that the reliability of the containment vessel wall becomes high and the effective head is high, so that the pipe diameter can be made thin.

Still another embodiment of the present invention will be described with reference to FIGS. 7 and 8. The difference from the embodiment shown in FIG. 6 is that a valve 70 is installed in the pipe 30 between the pressure vessel 1 and the water storage pool 31, and a pressure is installed in the pipe 32 between the water storage pool 31 and the pressure suppression pool 21. The point is that a check valve 71 is installed to prevent backflow from the pool 21.
The control method of the valve 70 will be described with reference to FIG. The water level of the pressure accumulator 40 is calculated from the signal from the differential pressure gauge 72 and the signal from the pressure gauge 73 by the density correction of the cooling water by the calculator 100, and the signal is sent to the main controller 103. Further, the water level of the pressure vessel 1 is obtained by correcting the density of the cooling water by the arithmetic unit 101 from the signal of the differential pressure gauge 74 and the signal of the pressure gauge 75, and the signal is sent to the main controller 103. The main controller 103, the water level of the accumulator 40 is a set value, for example, 0.1 m, lower,
Also, when the water level of the pressure vessel 1 has a certain set value, for example, 5 m below the upper end of the shroud 3
A signal for opening 70 is sent to the operation device 102. In such a nuclear reactor, assuming a coolant loss accident due to breakage of piping, for example, the water supply piping 6, the cooling water in the pressure vessel 1 flows out and the water level decreases. When the water level drops below a certain position, for example, 3 m below the upper end of the shroud 3, an automatic depressurization system start signal is issued, and after a certain time delay, for example, 120 seconds, the automatic depressurization system valve 10 is opened. As a result, a part of the steam generated in the core 2 flows from the valve 10 through the pipe 20 into the water storage section of the pressure suppression pool 21 and is condensed, so that the pressure vessel 1
The pressure inside is decreasing rapidly. When the pressure in the pressure vessel 1 becomes lower than the pressure in the pressure vessel 40, the cooling water in the pressure vessel 40 flows into the pressure vessel 1 through the pipe 41 and the check valve 42 for preventing the backflow from the pressure vessel 1. Then, the water level is maintained above the core 2. The cooling water in the accumulator 40 is all pressure container 1
If it flows into the core, the cooling water in the pressure vessel 1 will
Steam is generated due to heat generation in the water, and the water level gradually decreases. The water level in the pressure vessel 1 goes below the upper end of the shell 3.
When the position falls below the position of 5 m, a signal for opening the valve 70 is sent from the main controller 103 to the operating unit 102. When the valve 70 is opened, a part of the steam generated in the core 2 flows from the valve 70 through the pipe 30 into the upper space of the water storage pool 31. Water storage pool 31
The steam that has flowed into the upper space of the above further flows through the pressure equalizing pipe 32 into the water storage portion of the pressure suppression pool 21 and is condensed. As a result, the pressure in the upper space of the water storage pool 31 becomes almost the same as the pressure in the pressure vessel 1, and the check valve that prevents the cooling water in the water storage pool 31 from flowing back from the pipe 33 and the pressure vessel 1 due to gravity. It flows through the pressure vessel 1 through 34 and keeps the water level in the pressure vessel 1 above the core 2. In this embodiment, the pressure vessel 1
Since the valve 70 is opened after the pressure of is decreased, the heavy load generated when the steam flows in at a high speed is not generated. Also,
Since the cooling water in the pressure accumulating container 40 is exhausted and the cooling water is injected from the water storage pool 31 after the water level in the pressure container 1 is lowered, the injection timing of the cooling water is optimized and the water injection time is lengthened.

According to the present embodiment, there is an effect that no dynamic load is generated in the water storage pool and the water injection time becomes long.

Still another embodiment of the present invention will be described with reference to FIGS. 9 and 10. FIG. 10 is a sectional view taken along line BB in FIG. The difference from the embodiment shown in FIG. 1 is that the pressure suppression pool 21 and the water storage pool 31 are at the same level, and both are installed above the reactor core 2. In such a nuclear reactor, assuming a coolant loss accident due to breakage of piping, for example, the water supply piping 6, the cooling water in the pressure vessel 1 flows out and the water level decreases. Position where the water level is, for example, from the top of Shroud 3 to the bottom
The automatic depressurization system start signal is output for 3 m, which is lower, and after a certain time delay, for example, 120 seconds, the automatic depressurization system valve 10
And the valve 11 is opened. As a result, part of the steam generated in the core 2 passes from the valve 10 through the pipe 20 and the pressure suppression pool 21.
And then condensed into the water storage part, and the pressure in the pressure vessel 1 rapidly decreases. Further, a part of the steam generated in the core 2 flows from the valve 11 through the pipe 30 into the upper space of the water storage pool 31. The steam flowing into the upper space of the water storage pool 31 further passes through the pressure equalizing pipe 32 and flows into the water storage portion of the pressure suppression pool 21 to be condensed. When the pressure in the pressure vessel 1 decreases, the cooling water in the water storage pool 31 gravity causes the piping 33 and the pressure vessel 1 to flow.
It flows into the pressure vessel 1 through the check valve 34 that prevents the backflow from the inside of the pressure vessel 1 and keeps the water level above the core 2. The pressure in the upper space of the water storage pool 31 in the present embodiment is longer than that of a conventional device that guides steam into the water storage unit to condense the steam. It becomes higher by the sum of the blowout loss at the outlet of the hydrostatic head pipe. As a result, the effective head of water for injecting the cooling water is increased, and a pouring flow rate twice or more that of the conventional example can be obtained. Therefore, if the same water injection flow rate as in the conventional example is sufficient, reduce the diameter of the pipe 33 or use the water storage pool.
31 and the pressure suppression pool 21 can be installed at a low level position. As described above, the present invention is effective even when the water storage pool 31 and the pressure suppression pool 21 are at the same level.

According to this embodiment, since the effective head is high, the flow rate of water injection is increased.

Still another embodiment of the present invention will be described with reference to FIGS. 11 and 12. The difference from the embodiment shown in FIG. 7 is that the water storage pool
This is the point where pipes 80 and 81 are installed between the upper space of 31 and the upper space of the pressure suppression pool 21. The control method of valve 81 is the 12th
It will be described with reference to the drawings. The water level of the pressure accumulator 40 is calculated from the signal from the differential pressure gauge 72 and the signal from the pressure gauge 73 by the density correction of the cooling water by the calculator 100, and the signal is sent to the main controller 103. The water level of the pressure vessel 1 is obtained by correcting the density of the cooling water by the arithmetic unit 101 from the signal of the differential pressure gauge 74 and the signal of the pressure gauge 75, and the signal is sent to the main controller 103. Further, the water level of the water storage pool 31 is obtained by correcting the density of the cooling water by the calculator 104 from the signal of the differential pressure gauge 82 and the signal of the pressure gauge 83, and the signal is sent to the main controller 103. The main controller 103 sets the water level of the pressure accumulator 40 to a set value lower than, for example, 0.1 m, and the water level of the pressure container 1 to a set value lower than the upper end of the shroud 3 for example.
A signal for opening the valve 70 when it is lowered to the position of 5 m is sent to the operation device 102. Furthermore, if the water level in the water storage pool 31 falls below a certain value, for example 0.1 m, the main controller 10
3 sends a signal for closing the valve 70 to the operating unit 102 and a signal for opening the valve 81 to the operating unit 105. In such a reactor,
Assuming a coolant loss accident due to breakage of the pipe, for example, the water supply pipe 6, the cooling water in the pressure vessel 1 will flow out and the water level will drop. When the water level falls below a certain position, for example, 3 m below the upper end of the shroud 3, an automatic depressurizing system start signal is issued, and after a certain time delay, for example, 120 seconds, the automatic depressurizing system valve 10 is opened. As a result, a part of the steam generated in the core 2 flows from the valve 10 through the pipe 20 into the water storage portion of the pressure suppression pool 21 and is condensed, so that the pressure in the pressure vessel 1 rapidly decreases. When the pressure in the pressure vessel 1 becomes lower than the pressure in the pressure vessel 40, the cooling water in the pressure vessel 40 flows into the pressure vessel 1 through the pipe 41 and the check valve 42 for preventing the backflow from the pressure vessel 1. Then, the water level is maintained above the core 2.
When all the cooling water in the pressure accumulator 40 has flowed into the pressure vessel 1, the cooling water in the pressure vessel 1 evaporates due to heat generation in the core 2, and the water level gradually decreases. When the water level in the pressure vessel 1 drops below the position of 5 m below the upper end of the shroud 3, a signal to open the valve 70 from the main controller 103 is sent to the actuator 1
Sent to 02. When the valve 70 is opened, a part of the steam generated in the core 2 flows from the valve 70 through the pipe 30 into the upper space of the water storage pool 31. The steam flowing into the upper space of the water storage pool 31 further passes through the pressure equalizing pipe 32 and flows into the water storage portion of the pressure suppression pool 21 to be condensed. As a result, the pressure in the upper space of the water storage pool 31 becomes almost the same as the pressure in the pressure vessel 1, and the check valve that prevents the cooling water in the water storage pool 31 from flowing back from the pipe 33 and the pressure vessel 1 due to gravity. It flows through the pressure vessel 1 through 34 and keeps the water level in the pressure vessel 1 above the core 2. In this embodiment, since the valve 70 is opened after the pressure of the pressure vessel 1 has dropped, a dynamic load due to the inflow of steam is not generated. Further, since the cooling water in the pressure accumulator 40 is exhausted and the cooling water is injected from the water storage pool 31 after the water level in the pressure container 1 is lowered, the injection timing of the cooling water is optimized and the water injection time is lengthened. . After all the cooling water of the water storage pool 31 has been injected, the cooling water of the pressure suppression pool 21 is injected into the pressure vessel 1 using a pump of a residual heat removal system (not shown), or the pump is Using accumulator 40
The water level in the pressure vessel 1 is maintained above the core 2 by supplying cooling water to the core. When all the cooling water of the water storage pool 31 flows into the pressure vessel 1, the valve 70 is closed and the valve 81 is opened by the signal from the main controller 103. In the upper space of the pressure suppression pool 21, the non-condensable gas initially stored in the containment vessel 7 is collected. When the temperature in the water storage pool 31 decreases due to heat dissipation, the pressure decreases, and the non-condensable gas in the upper space of the pressure suppression pool 21 is piped.
It flows into the water storage pool through 80. As a result, in this embodiment, the partial pressure of the non-condensable gas is reduced by about 40%, and the pressure in the upper space of the pressure suppression pool 21, which is the sum of the partial vapor pressure and the vapor partial pressure, is about 40%.
30% lower. Therefore, the internal pressure of the containment vessel 7 is about 30%.
descend.

As described above, according to this embodiment, there is an effect that the internal pressure of the storage container is lowered for a long term.

Still another embodiment of the present invention will be described with reference to FIGS. 13 and 14. The difference from the embodiment shown in FIG. 11 is that the water storage part of the water storage pool 31 and the water storage part of the pressure suppression pool 21 are communicated with each other by using a pipe 80, and The outer pool 92 is installed on the outside. A method of controlling the valves 70 and 81 in this embodiment will be described with reference to FIG. Accumulator
40 water level, from the signal of the differential pressure gauge 72 and the signal of the pressure gauge 73,
Calculated by correcting the density of the cooling water by the calculator 100,
The signal is sent to the main controller 103. The water level of the pressure vessel 1 is calculated from the signal of the differential pressure gauge 74 and the signal of the pressure gauge 75 by the calculator 10
The density of the cooling water is corrected by 1 to obtain the signal, and the signal is sent to the main controller 103. Further, the water level of the water storage pool 31 is calculated from the signal of the differential pressure gauge 82 and the signal of the pressure gauge 83 by a calculator.
The density of the cooling water is corrected by 104 to obtain the signal, and the signal is sent to the main controller 103. The main controller 103 is a pressure accumulator
When the water level of 40 is lower than a certain set value, for example, 0.1 m, and the water level of the pressure vessel 1 is lower than a certain set value, for example, the position of 5 m below the upper end of the shroud 3, the valve 70 is lowered.
Is sent to the operating device 102. Further, when the water level in the water storage pool 31 falls below a certain value, for example, 0.1 m, the main controller 103 sends a signal b for forcibly closing the valve 70 to the operating device 102 and a signal for opening the valve 81. Send to operation device 105. At this time, the priority of the signal b is higher than that of the signal a. Next, when the water level of the water storage pool is low, if it rises above a certain set value, for example 3 m, the main controller
103 sends a signal to the actuator 102 to allow the valve 70 to open,
A signal for closing 81 is sent to the operation unit 105. In such a nuclear reactor, assuming a coolant loss accident due to breakage of piping, for example, the water supply piping 6, the cooling water in the pressure vessel 1 flows out and the water level decreases. When the water level falls below a certain position, for example, 3 m below the upper end of the shroud 3, a signal for the automatic pressure reducing system is issued, and after a certain time delay, for example, 120 seconds, the valve 10 of the automatic pressure reducing system is opened. As a result, a part of the steam generated in the core 2 flows from the valve 10 through the pipe 20 into the water storage portion of the pressure suppression pool 21 and is condensed, so that the pressure in the pressure vessel 1 rapidly decreases. When the pressure inside the pressure container 1 becomes lower than the pressure inside the pressure accumulating container 40, the check valve 42 that prevents the cooling water inside the pressure accumulating container 40 from flowing back from the pipe 41 and the pressure container 1.
To flow into the pressure vessel 1 and maintain the water level above the core 2. When all the cooling water in the pressure accumulator 40 has flowed into the pressure vessel 1, the cooling water in the pressure vessel 1 evaporates due to heat generation in the core 2, and the water level gradually decreases. When the water level in the pressure vessel 1 drops below the position of 5 m below the upper end of the shroud 3, the main controller 103 sends a signal to the operating unit 102 to open the valve 70. When the valve 70 is opened, a part of the steam generated in the core 2 flows from the valve 70 through the pipe 30 into the upper space of the water storage pool 31. The steam flowing into the upper space of the water storage pool 31 further passes through the pressure equalizing pipe 32 and flows into the water storage portion of the pressure suppression pool 21 to be condensed. As a result, the pressure in the upper space of the water storage pool 31 becomes almost the same as the pressure in the pressure vessel 1, and the check valve that prevents the cooling water in the water storage pool 31 from flowing back from the pipe 33 and the pressure vessel 1 due to gravity. It flows through the pressure vessel 1 through 34 and keeps the water level in the pressure vessel 1 above the core 2. When all the cooling water in the water storage pool 31 flows into the pressure vessel 1, the valve 70 is closed and the valve 81 is opened by the signal from the main controller 103. In this embodiment, a part of the wall of the water storage pool 31 uses the wall of the steel containment vessel 7, and the outer peripheral pool 92 is installed outside the wall of the containment vessel 7. For this reason, the steam inside the water storage pool 31 is rapidly cooled by heat radiation through the wall of the storage container 7, and the pressure rapidly drops below atmospheric pressure. On the other hand, the pressure in the upper space of the pressure suppression pool 21 is the sum of the partial pressure of the non-condensable gas and the vapor partial pressure.
2.5 to 3 atmospheres. Since the length of the pipe 80 is 9 m, the cooling water in the pressure suppression pool 21 rises in the pipe 80 due to the pressure difference and flows into the water storage pool 31. The water level of the water storage pool 31
When it rises above 3 m, the signal from the main controller 103 causes the valve 81
Is closed and a signal is sent to the actuator 102 allowing the valve 70 to open. At this time, when the water level of the pressure vessel 1 is lower than the position 5 m below the upper end of the shroud, the valve 70 is opened, and the cooling water in the water storage pool 31 flows into the pressure vessel 1 again and the pressure vessel 1
The water level is maintained above the core 2. As described above, in this embodiment, the cooling water of the water storage pool 31 can be continuously flown into the pressure vessel 1 by the pumping action based on the pressure difference, so that the water level of the pressure vessel 1 is extended to the upper portion of the core 2. Can be held for a period of time. Therefore, for example, the pump of the residual heat removing system can be deleted. Although the outer peripheral pool 92 is used to cool the water storage pool 31 in the present embodiment, it goes without saying that another method, for example, a heat pipe may be used.

According to this embodiment, since cooling water can be injected for a long period of time, there is an effect that dynamic equipment such as a pump can be deleted.

〔The invention's effect〕

In any of the inventions, the wall of the storage container can be effectively used, so that the installation rate is improved, and since the effective head is high, the water storage pool can be installed at the low level position.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, FIG. 2 is a vertical sectional view showing an operating state of the present invention, and FIG. 3 is an AA of FIG.
FIG. 4 is a transverse cross-sectional view taken along the arrow, and FIG. 4 is a graph showing the effect of the present invention.
FIG. 5 is a partial detailed view of the embodiment shown in FIG. 1, FIG. 6 is a vertical sectional view showing another embodiment of the present invention, and FIG. 7 is a vertical sectional view showing still another embodiment of the present invention. FIG. 8 is a diagram showing a control method of the embodiment of FIG. 7, FIG. 9 is a vertical sectional view showing still another embodiment of the present invention, and FIG. 10 is a partial sectional view of the embodiment of FIG. 11 is a longitudinal sectional view showing still another embodiment of the present invention, FIG. 12 is a view showing a control method of the embodiment of FIG. 11, and FIG.
FIG. 14 is a vertical sectional view showing still another embodiment of the present invention, and FIG. 14 is a view showing a control method of the embodiment of FIG. 1 ... Pressure vessel, 2 ... Reactor core, 3 ... Shroud, 4 ...
… Dryer, 5 …… Main steam pipe, 6 …… Water supply pipe, 7 …… Container, 10,11 …… Automatic decompression system valve, 21 …… Pressure suppression pool, 31 …… Water storage pool, 32 …… Pressure equalizing pipe, 34 …… Check valve, 40 …… Accumulator, 42 …… Check valve, 50 …… Vent pipe,
60 ... Heat shield plate, 70 ... Valve, 71 ... Check valve, 72 ... Differential pressure gauge, 73 ... Pressure gauge, 74 ... Differential pressure gauge, 75 ... Pressure gauge, 81 ...
… Valve, 82 …… Differential pressure gauge, 83 …… Pressure gauge, 100 …… Computer, 1
01 …… Calculator, 102 …… Operator, 103 …… Main calculator, 104
…… Calculator, 105 …… Operator.

Front page continuation (72) Terumi Kawasaki, Inventor, 1168 Moriyama-cho, Hitachi, Hitachi, Ibaraki Energy Research Institute, Ltd. (72) Masataka Hidaka, 1168, Moriyama-cho, Hitachi, Ibaraki, Hitachi, Ltd.Energy In the laboratory (56) Reference JP-A-62-237395 (JP, A)

Claims (8)

[Claims] 1. An emergency core cooling device for a nuclear reactor comprising a device for injecting cooling water into a reactor and a pressure suppression pool for condensing steam generated in the reactor, and water storage separate from the pressure suppression pool. A pool is installed, a flow path and a valve are installed between the reactor and the upper space of the water storage pool and the water storage section, respectively, and the upper space of the water storage pool and the water storage section of the pressure suppression pool are leveled. An emergency core cooling device, which is connected by pressure pipes, and a part of the water storage pool wall is a containment vessel wall surrounding the reactor pressure vessel. 2. The emergency core cooling system according to claim 1, wherein the water storage pool is placed above the pressure suppression pool. 3. The emergency core cooling system according to claim 1, wherein the valve between the reactor and the upper space of the water storage pool is automatically operated with a certain time delay after the reactor water level is lowered. Emergency core cooling device characterized in that it is a valve that opens dynamically. 4. The emergency core cooling device according to claim 1, wherein the pressure equalizing pipe is provided with a check valve for preventing backflow from the pressure suppression pool, and the upper space of the reactor and the water storage pool. An emergency core cooling device characterized in that a valve between and is opened when the flow rate of water injected into the reactor decreases and the reactor water level falls below a certain value. 5. The emergency core cooling apparatus according to claim 1, wherein the pressure equalizing tube has a shape in which the upper portion of the pressure equalizing tube widens toward the upper portion. 6. The emergency core cooling device according to claim 1, wherein a heat shield plate for protecting the wall of the containment vessel is installed inside a water storage pool provided inside the containment vessel. Emergency core cooling system. 7. The emergency core cooling device according to claim 4, wherein a flow path and a valve are installed between the upper space of the water storage pool and the upper space of the pressure suppression pool, An emergency characterized by closing the valve between the upper space of the water storage pool and the reactor when the water level drops and opening the valve between the upper space of the water storage pool and the upper space of the pressure suppression pool. Core cooling device. 8. The emergency core cooling system according to claim 4, wherein a flow path and a valve are installed between the water storage section of the water storage pool and the water storage section of the pressure suppression pool to store water. When the water level in the pool drops, close the valve between the upper space of the water storage pool and the reactor and open the valve between the water storage part of the water storage pool and the water storage part of the pressure suppression pool to store water. When the water level of the pool is restored, the valve between the water storage part of the water storage pool and the water storage part of the pressure suppression pool is closed to allow opening of the valve between the head space of the water storage pool and the reactor. An emergency core cooling device characterized by the above.