JP2022116105A - Fire extinction system for nuclear power plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fire extinction system of a nuclear power plant which does not release water if a sprinkler head goes wrong.

SOLUTION: A fire extinction system 1 of a nuclear power plant includes: a negative pressure sprinkler system 100 having a sprinkler head 103 and a secondary pipe 102 for supplying water to the sprinkler head 103, the pipe 102 being maintained in a negative pressure state in a normal state; a first pressure pump 204 for making the inside of the sprinkler pipe under a negative pressure; and a tank 401 located higher than the sprinkler head 103, the tank supplying water in the secondary pipe 102.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to fire suppression systems for nuclear power plants.

A conventional wet sprinkler is disclosed in Japanese Patent No. 3264939.

Patent No. 3264939

A problem with conventional sprinkler systems is that when the sprinkler head fails, water is released from the sprinkler head.

A nuclear power plant fire extinguishing system includes a sprinkler head, a sprinkler pipe for supplying water to the sprinkler head, and a negative pressure sprinkler system in which the sprinkler pipe is normally maintained in a negative pressure state, and the sprinkler A negative pressure device that can supply negative pressure to the sprinkler pipe and the negative pressure pipe, and a tank that supplies water to the sprinkler pipe and is located higher than the sprinkler head. and

In addition, a normal state means a normal state, and means a state in which no fire occurs. A nuclear power plant is a facility that uses the energy generated by nuclear transmutation to generate electricity.

In the fire extinguishing system of the nuclear power plant configured in this way, the sprinkler piping is normally maintained in a negative pressure state, so the amount of water in the sprinkler piping is reduced compared to when pressurized air is filled. can be quickly filled, so early water discharge is possible. Since the tank is located higher than the sprinkler head, even if the pump that supplies water from the tank to the sprinkler head stops, the force of gravity will still supply water from the tank to the sprinkler head. Water can be discharged from the sprinkler head even at times. The negative pressure state means a state lower than normal pressure (1 atm). Liquid may be present in the sprinkler line under negative pressure conditions.

1 is a schematic diagram of a fire extinguishing system of a nuclear power plant according to Embodiment 1; FIG. FIG. 3 is a schematic diagram of a fire extinguishing system for a nuclear power plant according to Embodiment 3; FIG. 4 is a schematic diagram of a fire extinguishing system for a nuclear power plant according to Embodiment 4; FIG. 11 is a schematic diagram of a fire extinguishing system for a nuclear power plant according to Embodiment 5; FIG. 12 is a schematic diagram of a fire extinguishing system of a nuclear power plant according to Embodiment 6;

(Embodiment 1)
(Configuration of Fire Extinguishing System for Nuclear Power Plants)
FIG. 1 is a schematic diagram of a fire extinguishing system for a nuclear power plant according to Embodiment 1. FIG. As shown in FIG. 1, a fire extinguishing system 1 for a nuclear power plant is installed in a building 10 of a nuclear power plant. The building 10 has a first section 11 which is a lower floor and a second section which is an upper floor.

The negative pressure sprinkler system 100 includes a primary pipe 101, a secondary pipe 102 connected to the primary pipe 101, a sprinkler head 103 provided in the secondary pipe 102, and a boundary between the primary pipe 101 and the secondary pipe 102. It has a valve 105 provided and a water pump 106 for sending water to the primary pipe 101 .

The primary pipe 101 is filled with water. This water is pressurized by the water pump 106 . The water pump 106 is supplied with water from a fire water tank (not shown). Water may be supplied to the water pump 106 from an elevated water tank on the top floor of the building 10 .

The primary pipe 101 rises vertically from the water pump 106 to the top of the building 10 and branches at each floor. Although the two-story building 10 is described in this embodiment, the floor of the building 10 is not limited to the second floor.

Water in the primary pipe 101 is stopped by a valve 105 , and the water in the primary pipe 101 is sent to the secondary pipe 102 by opening the valve 105 . Opening and closing of valve 105 is controlled by computer 302 .

Secondary pipe 102 is connected to valve 105 . A secondary pipe 102 is arranged in the second section 12 . Although this embodiment shows an example in which the valve 105 is arranged in the second section 12 , the valve 105 may be arranged in the first section 11 .

A secondary pipe 102 is arranged in the ceiling of the second compartment 12 . A plurality of sprinkler heads 103 are provided in the secondary pipe 102 . The number of sprinkler heads 103 is determined by the width of the second compartment 12 .

Although this embodiment shows an example in which the sprinkler head 103 is provided in the second section 12 , the secondary pipe 102 and the sprinkler head 103 may be arranged in the first section 11 .

The sprinkler head 103 is a closed sprinkler head, and is provided with a plurality of holes for discharging water. The sprinkler head 103 has a heat sensitive mechanism (a piece of fusible metal). In a normal state, the space between the hole for discharging water and the primary pipe 101 is shielded within the sprinkler head 103 . The barrier is opened when the heat sensitive mechanism is melted by the flames of the fire. Valve 105 is opened and water is discharged from the holes of sprinkler head 103 via primary pipe 101 and secondary pipe 102 .

The negative pressure system 200 includes a negative pressure pipe 201, a suction port 203 provided in the negative pressure pipe 201 to create a negative pressure in the building 10, and a first negative pressure pump 204 to create a negative pressure in the negative pressure pipe 201. , and a connection pipe 205 that connects the negative pressure pipe 201 and the secondary pipe 102 . A negative pressure sprinkler system can be realized only by providing a connection pipe 205 in the compartment and connecting the negative pressure pipe 201 and the secondary pipe 102 .

A first vacuum pump 204 is installed in the first compartment 11 to generate a vacuum. The first negative pressure pump 204 is configured by a negative pressure pump. Although the water pump 106 and the first vacuum pump 204 are installed in the same first compartment 11 in this embodiment, they may be installed in different compartments.

The negative pressure pipe 201 connected to the first negative pressure pump 204 rises vertically from the first negative pressure pump 204 to the top floor of the building 10 and branches at each floor. The negative pressure pipe 201 is branched on each floor, and the negative pressure pipe 201 is stretched around each room. A second negative pressure pump 214 is connected to the negative pressure pipe 201 . When the first negative pressure pump 204 is stopped during maintenance, for example, negative pressure can be supplied to the negative pressure pipe 201 using the second negative pressure pump 214 . The fire extinguishing system 1 of the nuclear power plant has a secondary pipe 102 as a sprinkler pipe and a first negative pressure pump 204 as a first negative pressure device for supplying negative pressure to the negative pressure pipe 201, and to the negative pressure pipe 201 and a second negative pressure pump 214 as a second negative pressure device for supplying negative pressure. In this embodiment, two negative pressure pumps, the first negative pressure pump 204 and the second negative pressure pump, are provided, but at least the first negative pressure pump 204 may be provided.

The building 10 of the nuclear power plant has the function of confining radioactive materials in the event of an accident. Therefore, the design is such that the inside of the building 10 is always maintained at a negative pressure. For example, the doorway has double doors to maintain negative pressure in the building. In this embodiment, the air inside the building 10 is sucked through the suction port 203 to create a negative pressure inside the building 10 . Either the first negative pressure pump 204 or the second negative pressure pump 214 may be used as the vacuum pump for maintaining the negative pressure in the building 10 in this manner. A suction port 203 for creating a negative pressure in the building 10 may be provided in addition to the connecting pipe 205 . Since the connection pipe 205 has an inner diameter necessary to create a negative pressure in the secondary pipe 102 , it may not be possible to secure a capacity for creating a negative pressure in the building 10 . Therefore, a pipe separate from the connecting pipe 205 is provided, this pipe is connected to at least one of the first negative pressure pump 204 and the second negative pressure pump 214, and the suction port 203 is provided in this pipe, so that the inside of the building 10 can be made negative pressure.

The negative pressure pipe 201 and the secondary pipe 102 are connected by a connecting pipe 205 . The connection pipe 205 and the secondary pipe 102 are connected at a connection point 202 . As a result, the pressure inside the secondary pipe 102 is kept negative in the normal state.

Under normal conditions, the pressure inside the secondary pipe 102 is negative and no water exists. The negative pressure can prevent water from remaining in the secondary pipe 102 . Even if water stays in the secondary pipe 102, the boiling point of water will be low under the negative pressure. Therefore, the water in the secondary pipe 102 boils and is sucked by the first negative pressure pump 204 through the connecting pipe 205 .

Detection system 300 has fire detector 301 and computer 302 . When a fire breaks out in the second compartment 12, the fire detector 301 detects the heat or smoke. Computer 302 and valve 105 are connected by signal line 311 . A signal line 312 connects the computer 302 and the water pump 106 .

An additional pipe 402 is connected to the primary pipe 101 . An additional pipe 402 is connected to the tank 401 . Water is stored in the tank 401 . The direction indicated by the arrow 403 is the vertically upward direction, and the tank 401 is located vertically above the sprinkler head 103 .

Even if the water pump 106 fails, if the valve 105 is opened, the water in the tank 401 flows into the secondary pipe 102 via the additional pipe 402 due to the action of gravity, and the water is discharged from the sprinkler head 103 .

When the water pump 106 is driven, the water pressure of the water pump 106 is added to the water in the primary pipe 101, and the water in the primary pipe 101 may flow into the additional pipe 402. It prevents the flow of water to the additional piping 402 . Alternatively, by providing a check valve in the additional pipe 402 , water can be prevented from flowing from the primary pipe 101 to the additional pipe 402 .

Although the additional piping 402 is provided outside the building 10 in this embodiment, the additional piping 402 may be provided inside the building 10 . In this case, freezing of water in the additional pipe 402 can be prevented.

The tank 401 may be provided inside the building 10 or may be provided outside the building 10 . If the tank 401 is installed inside the building 10 , all of the additional piping 402 can be installed inside the building 10 . As a result, the additional piping 402 can be protected. In addition, when an earthquake occurs, the building 10 shakes, but since the period of shaking of the building 10 differs from the period of shaking of the water in the tank 401, the shaking of the building 10 can be damped.

An antenna 410 is connected to the computer 302 . Antenna 410 can receive information about disasters, such as information about earthquakes. For example, the earthquake early warning can be obtained from a receiving terminal in addition to being obtained from a television, radio, mobile phone, etc., so that the antenna 410 can receive the emergency earthquake early warning. Information on disasters includes information on tsunamis, information on tornadoes, and information on hijacking. These are provided as disaster information from, for example, the Meteorological Agency, the Ministry of Land, Infrastructure, Transport and Tourism, the National Police Agency, and the like.

Computer 302 can control the output of water pump 106 and first vacuum pump 204 and second vacuum pump 214 . When the antenna 410 receives earthquake information, the computer 302 increases the output of at least one of the first negative pressure pump 204 and the second negative pressure pump 214 . That is, there is a high possibility that a fire will break out in the building 10 after an earthquake. The lower the pressure in the secondary pipe 102, the faster the secondary pipe 102 fills with water. Therefore, by increasing the output of at least one of the first negative pressure pump 204 and the second negative pressure pump to increase the degree of vacuum in the secondary pipe 102 (reduce the pressure in the secondary pipe 102), fire can be extinguished. When it occurs, the secondary pipe 102 can be immediately filled with water.

Furthermore, after an earthquake, the first negative pressure pump 204 and the second negative pressure pump 214 may not be driven due to power loss or the like. In this case, the pressure inside the secondary pipe 102 gradually increases and finally reaches the atmospheric pressure. The time it takes for the pressure in the secondary pipe 102 to reach the atmospheric pressure is related to the pressure in the secondary pipe 102 when the first negative pressure pump 204 and the second negative pressure pump 214 stop working. The lower the pressure in the secondary pipe 102 when the first negative pressure pump 204 and the second negative pressure pump 214 are no longer driven, the longer the pressure in the secondary pipe 102 after power loss until the pressure reaches the atmospheric pressure. it takes longer.

Since the seismic intensity of the building 10 changes according to the magnitude of the earthquake and the distance from the epicenter (seismic center) to the building 10 of the nuclear power plant, the first negative pressure pump 204 and the second negative pressure pump 204 and the second negative pressure Change the output of pump 214 . As an example, it is possible to change the outputs of the first negative pressure pump and the second negative pressure pump based on the following table.

"A" in Table 1 indicates that the outputs of the first vacuum pump 204 and the second vacuum pump 214 are maximum. "B" indicates that the outputs of the first vacuum pump 204 and the second vacuum pump 214 are moderate. "C" indicates that the outputs of the first negative pressure pump 204 and the second negative pressure pump 214 are made larger than before receiving the disaster information, but smaller than "B". In any case, the output of either the first negative pressure pump 204 or the second negative pressure pump 214 is increased compared to before the disaster information is received by the antenna 410, and the secondary piping is more effective than before the reception. Decrease pressure at 102 .

In this way, by determining the outputs of the first negative pressure pump 204 and the second negative pressure pump 214 according to the seismic intensity expected in the building 10, the first negative pressure pump 204 and the second negative pressure pump 214 You can avoid wasting energy.

When computer 302 receives disaster information via antenna 410 , the output of water pump 106 may be increased to increase the water pressure in primary pipe 101 . As a result, the secondary pipe 102 is quickly filled with water when the valve 105 is opened.

When the computer 302 receives disaster information via the antenna 410 , the power of the water pump 106 may be increased to move water from the pool (not shown) to the tank 401 . As a result, the secondary pipe 102 can be reliably filled with the water in the tank 401 even if the power source is lost after a disaster.

The above fire extinguishing system 1 for a nuclear power plant has a sprinkler head 103 and a secondary pipe 102 as a sprinkler pipe for supplying water to the sprinkler head 103, and the secondary pipe 102 is in a normal negative pressure state. a negative pressure sprinkler system 100 maintained at , a negative pressure pipe 201 connected to the secondary pipe 102, and a first negative pressure device as a negative pressure device capable of supplying negative pressure to the secondary pipe 102 and the negative pressure pipe 201 A pressure pump 204 and a tank 401 that supplies water to the secondary pipe 102 and is provided at a position higher than the sprinkler head 103 are provided.

The fire extinguishing system 1 of the nuclear power plant comprises a computer 302 as control means for receiving disaster information and controlling the negative pressure generated by the first negative pressure pump 204 according to the disaster information.

A fire extinguishing system 1 of a nuclear power plant is provided with a first negative pressure pump 204 capable of supplying negative pressure to a secondary pipe 102 and a negative pressure pipe 201 and creating a negative pressure inside the building.

Note that the tank 401 and the additional pipe 402 may not necessarily be provided. Antenna 410 may not necessarily be provided.

(Operation of Fire Extinguishing System in Nuclear Power Plant)
When a fire breaks out in the second compartment 12, the fire detector 301 detects heat or smoke from the fire. Detected information is sent from the fire detector 301 to the computer 302 . Computer 302 signals valve 105 to open. Computer 302 drives water pump 106 or increases the driving power of water pump 106 . As a result, water is filled in the secondary pipe 102, which was in a negative pressure state without water in the normal state.

The heat from the fire melts the heat sensitive features of the sprinkler head 103 . Thereby, the hole for water discharge of the sprinkler head 103 and the secondary pipe 102 are connected. Water can be discharged from the water discharge holes of the sprinkler head 103 to extinguish the fire.

If the power is lost, the valve 105 is manually opened. Or prepare a power supply of another system so that the valve can be opened. By opening the valve 105 manually or by a power source of another system, the water in the tank 401 flows to the secondary pipe 102 via the additional pipe 402 . Thereby, water can be discharged from the sprinkler head 103 .

(effect)
In the nuclear power plant fire extinguishing system 1 configured in this way, the first negative pressure pump 204 is a pump for making the inside of the building 10 negative pressure, and is also a pump for making the secondary pipe 102 negative pressure. . Since the pump for depressurizing the building 10 is originally provided in the nuclear power plant, the inside of the secondary pipe 102 can be made negative pressure without adding new equipment.

By opening the valve 105 manually or by a power supply of another system at the time of power loss, the water in the tank 401 is sent to the secondary pipe 102 via the additional pipe 402 , whereby the water can be discharged from the sprinkler head 103 . As a result, it is possible to respond to a fire even when power is lost.

The connection pipe 205 is provided in the second section 12 where the negative pressure pipe 201 and the secondary pipe 102 are provided. Therefore, the connection pipe 205 of the negative pressure pipe 201 and the secondary pipe 102 can be shortened, and the construction cost can be reduced.

Furthermore, compared with the dry sprinkler system (pre-actuation sprinkler system) in which the secondary pipe is normally under normal pressure or pressurized, the negative pressure sprinkler system 100 according to Embodiment 1 (nuclear power plant fire extinguishing system 1) has the following effects. In the normal pressure dry sprinkler system, when a fire occurs, the pump operates to fill the secondary pipe with water. Water does not fill in the secondary piping. On the other hand, in the negative pressure sprinkler system 100, since the inside of the secondary pipe 102 has a negative pressure, the inside of the secondary pipe 102 is smoothly filled with water. Therefore, it is possible to solve the problem of the delay in sprinkling water from the sprinkler head, which was a drawback of conventional dry sprinklers (pre-actuation sprinklers).

In order to increase the degree of vacuum in the secondary pipe 102 by increasing the output of either the first negative pressure pump 204 or the second negative pressure pump 214 when the antenna 410 receives disaster information, water is supplied from the sprinkler head 103 in the event of a disaster. The time until the water is discharged is shortened. Specifically, when the valve 105 is opened and the degree of vacuum in the secondary pipe 102 is high, water flows into the secondary pipe 102 at once, so that water can be discharged from the sprinkler head 103 immediately. Furthermore, since the amount of air sucked per unit time from the suction port 203 increases, even if the building 10 is damaged by a disaster, radioactive materials are less likely to leak out of the building 10 .

(Embodiment 2)
In the fire extinguishing system 1 of the nuclear power plant according to Embodiment 2, the negative pressure pipe 201 is normally filled with water and kept in a negative pressure state. Other configurations are common to the nuclear power plant fire extinguishing system 1 of the first embodiment. In order to prevent water from flowing directly into the first negative pressure pump 204 and the second negative pressure pump 214, a water impermeable but air permeable membrane is provided on the first negative pressure pump 204 and the second negative pressure pump 214; It may be provided between the pipe 201 for negative pressure. Further, the secondary pipe 102 is normally filled with water, and the negative pressure pipe 201 is not filled with water. good too. In any of the following embodiments, wet type negative pressure sprinklers may also be used.

That is, the negative pressure sprinkler system 100 according to the second embodiment is a wet negative pressure sprinkler system. Since the pressure in the negative pressure pipe 201 is low, the negative pressure pipe 201
The water inside easily evaporates. When the water in the negative pressure pipe 201 evaporates and decreases, a system is adopted to replenish the decreased water. For example, when the water in the negative pressure pipe 201 decreases, the sensor detects the decrease in water, the sensor sends a signal to the computer 302, and the computer 302 slightly opens the valve 105 to supply water to the negative pressure pipe 201. may

Suppose one sprinkler head 103 is damaged. In this case, since the suction force by the connecting pipe 205 is stronger than the force that causes water to leak from the damaged sprinkler head 103, water is not discharged from the damaged sprinkler head 103. When multiple sprinkler heads 103 are damaged at the same time, water is discharged from the damaged sprinkler heads 103, but the possibility of multiple sprinkler heads 103 being damaged at the same time is extremely low.

(Embodiment 3)
FIG. 2 is a schematic diagram of a fire extinguishing system for a nuclear power plant according to the third embodiment. In Embodiment 3, a fire extinguishing system 1 for a nuclear power plant has a sprinkler head 103 and a secondary pipe 102 as a sprinkler pipe for supplying water to the sprinkler head 103, and the secondary pipe 102 is in a normal state. and a first negative pressure pump 204 as a negative pressure device capable of supplying negative pressure to the sprinkler pipe. The pipe 211 and the secondary pipe 102 are connected at a connection point 212 . A pipe 211 is connected to the first negative pressure pump 204 . A first vacuum pump 204 can supply vacuum to line 211 and secondary line 102 .

Also in this embodiment, it is possible to prevent water from leaking from the sprinkler head 103 in the nuclear power plant.

(Embodiment 4)
FIG. 3 is a schematic diagram of a fire extinguishing system for a nuclear power plant according to a fourth embodiment. In Embodiment 4, a fire extinguishing system 1 for a nuclear power plant has a sprinkler head 103 and a secondary pipe 102 as a sprinkler pipe for supplying water to the sprinkler head 103. A negative pressure sprinkler system 100 in which the next pipe 102 is normally maintained in a negative pressure state, a negative pressure pipe 201 for supplying negative pressure used in the nuclear power plant, and a negative pressure in the secondary pipe 102 and the negative pressure pipe 201. A first negative pressure pump 204 and a second negative pressure pump 214 are provided as first and second negative pressure devices capable of supplying pressure.

A pipe 211 connects the first negative pressure pump 204 and the second negative pressure pump 214 to the secondary pipe 102 .

A valve 209 is provided on the negative pressure pipe 201 . A valve 219 is provided in the pipe 211 . The opening and closing of valves 209 and 219 are controlled by computer 302 .

During normal operation, the valves 209 and 219 are opened and closed so that the first negative pressure pump 204 supplies negative pressure to the negative pressure pipe 201 and the second negative pressure pump 214 supplies negative pressure to the pipe 211 and the secondary pipe 102. is controlled.

On the other hand, when the first negative pressure pump 204 is stopped for maintenance, the valve 209 and the 219 is controlled to open and close.

When the second negative pressure pump 214 is stopped for maintenance, opening and closing of the valves 209 and 219 are controlled so that the first negative pressure pump 204 supplies negative pressure to the negative pressure pipes 201, 211 and 102. be done.

(Embodiment 5)
4 is a schematic diagram of a fire extinguishing system for a nuclear power plant according to Embodiment 5. FIG. In Embodiment 5, a fire extinguishing system 1 for a nuclear power plant has a sprinkler head 103 and a secondary pipe 102 as a sprinkler pipe for supplying water to the sprinkler head 103. A negative pressure sprinkler system 100 in which the next pipe 102 is normally maintained in a negative pressure state, a negative pressure pipe 201 for supplying negative pressure used in the nuclear power plant, and a negative pressure can be supplied to the negative pressure pipe 201 A first negative pressure pump 204 as a first negative pressure device and a second negative pressure pump 214 as a second negative pressure device capable of supplying negative pressure to the secondary pipe 102 and the negative pressure pipe 201 are provided.

During normal operation, the opening and closing of the valve 209 is controlled so that the first negative pressure pump 204 supplies negative pressure to the negative pressure pipe 201 and the second negative pressure pump 214 supplies negative pressure to the pipe 211 and the secondary pipe 102. be done.

On the other hand, when the first negative pressure pump 204 is stopped for maintenance, the valve 209 is opened so that the second negative pressure pump 214 supplies negative pressure to the negative pressure pipe 201, the pipe 211 and the secondary pipe 102. Controlled opening and closing.

(Embodiment 6)
FIG. 5 is a schematic diagram of a fire extinguishing system for a nuclear power plant according to a sixth embodiment. In Embodiment 6, a fire extinguishing system 1 for a nuclear power plant has a sprinkler head 103 and a secondary pipe 102 as a sprinkler pipe for supplying water to the sprinkler head 103, and the secondary pipe 102 is in a normal state. a negative pressure sprinkler system 100 maintained in a negative pressure state, a negative pressure pipe 201 for supplying negative pressure used in the nuclear power plant, and a first negative pressure device capable of supplying negative pressure to the negative pressure pipe 201 a second negative pressure pump 214 as a second negative pressure device capable of supplying negative pressure to the secondary pipe 102 and the negative pressure pipe 201; and a negative pressure to the secondary pipe 102. and a third vacuum pump 218 as a possible third vacuum device.

During normal operation, the valves 209 and 219 are opened and closed so that the first negative pressure pump 204 supplies negative pressure to the negative pressure pipe 201 and the second negative pressure pump 214 supplies negative pressure to the pipe 211 and the secondary pipe 102. is controlled.

On the other hand, when the first negative pressure pump 204 is stopped for maintenance, the second negative pressure pump 214 supplies negative pressure to the negative pressure pipe 201, and the third negative pressure pump 218 supplies the negative pressure to the pipe 211 and the secondary pressure pipe. Opening and closing of valves 209 and 219 are controlled so as to supply negative pressure to pipe 102 .

When the second negative pressure pump 214 is stopped for maintenance, the first negative pressure pump 204 supplies negative pressure to the negative pressure pipe 201, the pipe 211, and the secondary pipe 102, and the third negative pressure pump 218 supplies the pipe 211 with negative pressure. and the opening and closing of the valves 209 and 219 are controlled so as to supply negative pressure to the secondary pipe 102 .

The embodiments disclosed this time are illustrative in all respects and should not be considered restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above-described embodiments, and is intended to include meanings equivalent to the scope of the claims and all modifications within the scope.

1 fire extinguishing system of nuclear power plant, 10 building, 11 first compartment, 12 second compartment, 100 negative pressure sprinkler system, 101 primary pipe, 102 secondary pipe, 103 sprinkler head, 105, 209, 219 valve, 106 water pump , 200 negative pressure system, 201 negative pressure piping, 202, 212 connection point, 203 suction port, 204 first negative pressure pump, 205 connection pipe, 214 second negative pressure pump, 218 third negative pressure pump, 300 detection system, 301 fire detector, 302 computer, 311, 312
Signal line, 401 tank, 402 additional pipe, 403 arrow, 410 antenna.

Claims (3)

A fire extinguishing system for a nuclear power plant, comprising:
a negative pressure sprinkler system having a sprinkler head and a sprinkler pipe for supplying water to the sprinkler head, wherein the sprinkler pipe is normally maintained in a negative pressure state;
a negative pressure pipe connected to the sprinkler pipe;
a negative pressure device capable of supplying negative pressure to the sprinkler pipe and the negative pressure pipe;
and a tank that supplies water to the sprinkler pipe and is provided at a position higher than the sprinkler head. A fire extinguishing system for a nuclear power plant, comprising:
a negative pressure sprinkler system having a sprinkler head and a sprinkler pipe for supplying water to the sprinkler head, wherein the sprinkler pipe is normally maintained in a negative pressure state;
a negative pressure pipe connected to the sprinkler pipe;
a negative pressure device capable of supplying negative pressure to the sprinkler pipe and the negative pressure pipe;
A fire extinguishing system for a nuclear power plant, comprising control means for receiving disaster information and controlling the negative pressure generated by the negative pressure device according to the disaster information. A fire extinguishing system for a nuclear power plant, comprising:
a negative pressure sprinkler system having a sprinkler head provided in a building and a sprinkler pipe for supplying water to the sprinkler head, wherein the sprinkler pipe is normally maintained in a negative pressure state;
a negative pressure pipe connected to the sprinkler pipe;
A fire extinguishing system for a nuclear power plant, comprising: a negative pressure device capable of supplying a negative pressure to the sprinkler pipe and the negative pressure pipe, and creating a negative pressure in the building.

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