JP2016194420A - Atomic reactor water level measuring method in emergency, apparatus for the same, and method of pouring water into atomic reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method by which the water level in an atomic reactor can be reliably measured even when the atomic reactor has lost electric power supply from outside, a power source for emergency source has also become unusable and further the sea water cooling function has been lost, and an apparatus for implementing the method.SOLUTION: A sealed cylindrical chamber 33 substantially the same in height and longitudinal length as an atomic reactor 1 is installed in advance; piping 19 branched in a T shape from an instrumentation tube 14 drawn from the atomic reactor 1 is connected to a lower part of the chamber 33; the upper part of the chamber 33 and the gas phase part of the atomic reactor 1 are linked by piping; the water level in the chamber 33 is kept the same all the time as that in the atomic reactor 1; a zigzag-shaped liquid level gauge 40 is installed in the chamber 33 in the lengthwise direction; a transparent tempered glass window is opened on a side face of the chamber 33 in a position opposite the liquid level gauge 40; and the water level in the atomic reactor 1 is measured by visual observation of the zigzag-shaped liquid level gauge 40 inside through the window of the chamber 33.SELECTED DRAWING: Figure 2

Description

In the boiling water reactor, the present invention makes it possible to maintain the reactor in a stable state for a long time even in an emergency where the external power source is lost, the emergency power source cannot be used, and the seawater cooling function is lost. The present invention relates to a method and apparatus for measuring the water level of a nuclear reactor, and further relates to a method of injecting water into the nuclear reactor when the water level is lowered. It is intended to prevent damage to the reactor containment vessel.

In boiling water reactors, the external power supply is lost for some reason, the emergency power supply becomes unusable, and the seawater cooling function is lost. Power is supplied from a DC power source, the reactor is emergency stopped, the core is cooled, and the nuclear power plant can be maintained in a safe state.

In the conventional nuclear power plant, during normal operation of the plant, steam generated in the nuclear reactor 1 is sent to the turbine 3 via the main steam pipe 2 as shown in FIG. The exhaust steam that has worked in the turbine 3 is condensed in the condenser 4 to become condensate, is pressurized by the condensate pump 5 through the condensate pipe, passes through the feed water heater 6 and the feed water header 7, and finally the reactor 1. Constitutes a cycle back to. Water supply check valves 25 and 26 are provided in the middle of the piping from the water supply header 7 to the reactor 1.

Further, when the external power source or the like is lost, the nuclear reactor is automatically stopped and the nuclear reactor 1 and the turbine 3 are separated. Then, the steam relief valve 8 allows the steam pressure to escape to the pressure suppression chamber 9 and condense, and the pump 11 is operated by the steam-driven reactor isolation cooling turbine 10, and the pressure suppression chamber 9 or condensate is operated. Water from the storage tank 12 is poured into the reactor 1. This situation has been maintained for more than 10 hours, and there is a track record of being able to maintain driving for up to 3 days at the time of an accident.

Further, as shown in FIG. 6, the water level measuring device in the nuclear reactor 1 is connected to the gas phase portion of the nuclear reactor 1 through a coagulation tank 15, and penetrates the nuclear reactor containment vessel 24 to pass through the nuclear reactor containment vessel. A reference pressure conduit 16 that extends outside the reactor 24, a water level pressure conduit 17 that is connected to the liquid phase of the reactor 1, passes through the reactor containment vessel 24, and extends outside the reactor containment vessel 24; A differential pressure between the reference pressure introduced from the reference pressure conduit 16 and the water level pressure introduced from the water level pressure conduit 17 as a state quantity corresponding to the water level in the reactor 1 is arranged outside the reactor containment vessel 24. And a differential pressure gauge 18 to be measured.

The condensing tank 15 is disposed inside the reactor containment vessel 24. Then, the steam flowing into the condensation tank 15 from the gas phase portion of the nuclear reactor 1 dissipates heat and condenses, and the condensed water is stored in the condensation tank 15 and the reference pressure conduit 16. Further, excessive water is returned to the reactor 1 in order to keep the water surface height in the condensing tank 15 constant.

The reference pressure introduced into the differential pressure gauge 18 from the reference pressure conduit 16 includes the liquid phase pressure (reference head) due to the water surface height in the condensing tank 15 and the gas phase pressure in the condensing tank 15 (in other words, approximately And the pressure of the gas phase in the nuclear reactor 1). On the other hand, the water level pressure introduced into the differential pressure gauge 18 from the water level pressure conduit 17 is the sum of the liquid phase pressure (water level head) that fluctuates according to the water level of the reactor 1 and the gas phase pressure in the reactor 1. It is. The differential pressure gauge 18 measures the above-described differential pressure between the reference pressure and the water level pressure (that is, approximately the differential pressure between the reference water head and the water level head), and outputs a water level signal based on this to a display device or the like outside the figure. . This is also described in FIG. 9 showing a conventional example of Patent Document 1.

In addition, as shown in Patent Document 2, a method for injecting water into a nuclear reactor and cooling it when power is lost and seawater cannot be cooled has been developed. This is a method in which a high-pressure washing pump is connected to an instrumentation pipe connected from a nuclear reactor to an instrument installed outside the reactor containment vessel, and fresh water is injected into the reactor from the high-pressure washing pump.

JP-A-6-331784 JP 2014-29300 A

In the conventional technique shown in Patent Document 1, it is possible to keep the reference head due to the water surface height in the condensing tank 15 constant during normal operation, and accurately measure the water level in the reactor 1. Is possible. However, in an emergency in which the temperature in the reactor containment vessel 1 is higher than that in normal operation and the water level in the reactor 1 is lower than that in normal operation, for example, the water in the condensing tank 15 evaporates and the water level rises. Fluctuates and the standard head fluctuates. Therefore, a water level measurement error occurs. When the power supply is lost, the condensing tank 15 is in a dry state, the differential pressure gauge 18 does not operate, and measurement is impossible.

In the method of Patent Document 2, a high-pressure washing pump must be prepared because high-pressure washing water is directly injected into the nuclear reactor through instrumentation piping.

Therefore, in view of these prior arts, the present invention eliminates the external power source, makes the emergency power source unusable, and further reduces the water level of the reactor even in an emergency such as loss of the seawater cooling function. The present invention provides a method capable of reliably measuring and a device therefor, and a method capable of easily injecting cooling water into a nuclear reactor using these devices.

The invention of claim 1 is a method for measuring the water level in a nuclear reactor in the event of an emergency such as loss of power, and includes a cylindrical sealed chamber having substantially the same height and substantially the same longitudinal length as the nuclear reactor. Connected to the lower part of the chamber by connecting a pipe formed by T-branching an instrumentation pipe led out from the reactor in advance, and connecting the liquid phase part of the nuclear reactor and the chamber; The reactor is connected to the gas phase part by piping, and the water level in the chamber is always the same as the water level in the reactor, and a staggered liquid level gauge is provided in the chamber in the longitudinal direction. Water level of the reactor in an emergency, where a transparent tempered glass window is provided on the side of the chamber at the opposite position, and the water level of the reactor is measured by visually observing a staggered level gauge through the window of the chamber The measurement method was used.

According to a second aspect of the present invention, there is provided a cylindrical sealed chamber having substantially the same height and substantially the same vertical length as a nuclear reactor in a method of measuring the water level in a nuclear reactor in an emergency such as loss of power. Is connected to the lower part of the chamber to connect the liquid phase part of the reactor and the chamber, and the upper part of the chamber is connected to the upper part of the chamber. The gas phase part of the reactor is connected by piping, the water level in the chamber is always the same as the water level of the reactor, and an ultrasonic emission device is provided at the top of the chamber, and the outside of the reactor containment vessel The reactor water level measurement method in an emergency is to measure the water level in the chamber by emitting ultrasonic waves into the chamber by the ultrasonic water level measurement device provided in the reactor.

According to a third aspect of the present invention, there is provided a cylindrical sealed chamber having substantially the same height and substantially the same longitudinal length as a nuclear reactor in a method of measuring the water level in the nuclear reactor in an emergency such as a loss of power. Is connected to the lower part of the chamber to connect the liquid phase part of the reactor and the chamber, and the upper part of the chamber is connected to the upper part of the chamber. The reactor gas phase was connected by piping, the water level in the chamber was always the same as the water level in the reactor, and a core wire was provided in the tube made of an electrical conductor in the longitudinal direction in the chamber. A special cable like a coaxial cable is provided, a TDR measuring instrument provided outside the containment vessel is connected to the special cable, and a pulse wave is emitted from the TDR measuring instrument to the special cable in the chamber. The distance from the arrival time of the reflected wave of the pulse wave is measured, thereby measuring the water level in the chamber, and a water level measuring method of the reactor in emergency.

According to a fourth aspect of the present invention, there is provided a device for measuring a water level in a nuclear reactor in the event of an emergency such as a loss of power, and a cylindrical sealed chamber having substantially the same height and substantially the same longitudinal length as the nuclear reactor. Is connected to the lower part of the chamber to connect the liquid phase part of the nuclear reactor and the chamber, and the upper part of the chamber is connected to the lower part of the chamber. And the gas phase part of the reactor are connected by piping, the water level in the chamber is always the same as the water level of the reactor, and a staggered liquid level gauge is provided in the longitudinal direction in the chamber, A transparent tempered glass window is provided on the side of the chamber facing the gauge, and the staggered liquid level gauge inside is visually observed through the window of the chamber in case of an emergency such as loss of power to the reactor or shutdown of cooling water. And measure the water level in the reactor Possible and the was water level measuring device of the reactor in emergency.

According to a fifth aspect of the present invention, there is provided an apparatus for measuring a water level in a nuclear reactor in the event of an emergency such as a loss of power, and a cylindrical sealed chamber having substantially the same height and substantially the same longitudinal length as the nuclear reactor. Is connected to the lower part of the chamber to connect the liquid phase part of the reactor and the chamber, and the upper part of the chamber is connected to the upper part of the chamber. The gas phase part of the reactor is connected by piping, the water level in the chamber is always the same as the water level of the reactor, and an ultrasonic emission device is provided at the top of the chamber, and the outside of the reactor containment vessel The ultrasonic water level measuring device provided in the reactor was used to emit ultrasonic waves into the chamber so that the water level in the chamber could be measured.

The invention of claim 6 is an apparatus for measuring the water level in a nuclear reactor in the event of an emergency such as a loss of power, and is sealed in a cylindrical shape having substantially the same height and substantially the same longitudinal length as the nuclear reactor. A chamber is provided in advance, and a tube obtained by branching an instrumentation tube led out from the reactor is connected to the lower portion of the chamber to connect the liquid phase portion of the reactor and the chamber, and the upper portion of the chamber And the gas phase part of the reactor are connected by piping, the water level in the chamber is always the same as the water level of the reactor, and a core wire is provided in a pipe made of an electrical conductor in the longitudinal direction in the chamber. A special cable like a coaxial cable is provided, a TDR measuring instrument provided outside the containment vessel and the special cable are connected, and a pulse wave is emitted from the TDR measuring instrument to the special cable in the chamber, The distance from the return time to TDR instrument of the reflected wave of the pulse wave is measured, thereby to allow measuring the water level in the chamber, and a water level measuring device of the reactor in emergency.

The invention according to claim 7 is the apparatus according to any one of claims 4 to 6, wherein the pipe branched from the instrumentation pipe and the upper part of the chamber are connected to the gas phase part of the reactor. Close the valves provided in the pipes respectively, open the exhaust or drain opening provided in the upper or lower part of the chamber, inject cold water into the chamber, fill the chamber, and then fill the plug. Is closed and the valves are opened to enter the reactor until the water in the chamber reaches the same level as the lowered reactor water level, and these steps are repeated several times to enter the reactor. A method of injecting cold water into the reactor in an emergency was adopted.

The invention according to claim 8 is the apparatus according to any one of claims 4 to 6, wherein the pipe branched from the instrumentation pipe and the upper part of the chamber are connected to the gas phase part of the reactor. Close the valves provided in each of the pipes, open the exhaust or drain opening provided in the upper or lower part of the chamber, inject cold water into the chamber, fill the chamber, and then The stopper was closed, cold water was poured from the chamber into the spent nuclear fuel storage pool, and these steps were repeated multiple times to provide a method for pouring the spent nuclear fuel storage pool in an emergency.

According to the first and fourth aspects of the present invention, even when the external power supply is lost and the emergency power supply cannot be used, the internal staggered pattern can be seen from the transparent glass window of the same water level as the reactor. The liquid level gauge can be visually observed, and the water level in the chamber and the water level in the reactor can be confirmed by the liquid level gauge. Further, if the transparent glass window of the chamber is opposed to the door of the large building entrance of the reactor building or the emergency exit, the liquid level gauge in the chamber can be passed through these openings even from outside the reactor building. The water level can be measured. Furthermore, if a camera is provided outside the window of the chamber and a liquid level gauge is photographed with the camera, the water level of the reactor can be measured even from a long distance. In addition, a power source is not necessary for these measurements, and it is suitable in an emergency.

Further, according to the inventions of claim 2 and claim 5, even when the external power supply is lost and the emergency power supply cannot be used, the reactor is stored toward the water surface of the chamber having the same water level as the reactor. Ultrasonic waves are emitted from the outside of the vessel or reactor building using an ultrasonic level meter, and the water level in the chamber is measured based on the return time of the reflected waves from the water surface. The water level in the furnace can be measured.

According to the third and sixth aspects of the present invention, even when the external power source is lost and the emergency power source cannot be used, the reactor containment vessel is directed toward the water surface of the chamber having the same water level as the reactor. Because the pulse wave is emitted from the outside of the TDR level meter to the special cable in the chamber and the water level in the chamber is measured by the return time of the reflected wave of the pulse wave from the water surface in the chamber. The water level in the reactor can be measured from a remote location.

According to the invention of claim 7, even when the external power source is lost and the emergency power source cannot be used, the reactor and the chamber are isolated by the valve, and the fire is not contained in the chamber not at high pressure. Water is injected with a hose or the like, the chamber is filled with water and sealed, and the valve is opened to connect the reactor and the chamber. Thereby, water is poured into the reactor by the gravity of the water in the chamber. Therefore, it is possible to easily inject cold water into the nuclear reactor without using a conventional high-pressure washing pump.

Further, according to the invention of claim 8, even when the external power source is lost and the emergency power source cannot be used, the reactor and the chamber are isolated by a valve, and the fire fighting is performed in the chamber which is not at a high pressure. Water can be poured with a hose, etc., the chamber can be filled and sealed, and cold water in the chamber can be injected into the spent fuel storage pool. At that time, the spent fuel storage pool is generally located at the upper part of the nuclear reactor, and water injection from the chamber into the spent fuel storage pool is easy without changing the height level.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of the water level measuring device of the reactor in emergency of Embodiment 1 of this invention. It is an expanded schematic block diagram of the principal part of the water level measuring device of the reactor of Embodiment 1 of this invention. It is an enlarged front view of the principal part of the water level measuring device of the nuclear reactor of Embodiment 1 of this invention. It is a block diagram which shows one principle of the water level measuring apparatus of the reactor of Example 1 of this invention. It is a schematic block diagram of the conventional boiling nuclear reactor. It is a schematic block diagram which shows the water level measuring apparatus of the conventional boiling reactor.

An apparatus used for the reactor water level measurement method according to the first embodiment of the present invention will be described with reference to the drawings.

1 and 2, a cylindrical sealed chamber 33 having the same height as the nuclear reactor 1 and substantially the same length in the vertical direction is provided. The chamber 33 is provided in a reactor building (not shown) outside the reactor containment vessel 24. In addition, in order to measure the pressure, water level, and flow rate of the reactor 1, a number of instruments 13 provided outside the reactor containment vessel 24 from the reactor 1 (see FIG. 2, but only one is shown in FIG. 2). Dozens of instrumentation pipes 14 (two are shown in FIG. 1 and only one is shown in FIG. 2) are provided. A branch joint 27 (see FIG. 2) is provided in each of a plurality of instrumentation pipes 14 among them, and a pipe 19 with an overflow check valve 32 is connected to each branch joint 27, and the other end of the pipe 19 is connected to the other end. It is connected to the lower part of the chamber 33. Therefore, the lower part of the chamber 33 and the liquid phase part of the nuclear reactor 1 are connected via the pipe 19 and the instrumentation pipe 14.

The chamber 33 is connected to the external water supply tank 20 through a pipe 35 provided with an opening / closing valve 34 from the lower part. The reactor 33 is connected to the water supply system of the reactor separation cooling system from the upper part of the chamber 33 through a pipe 37 with an overflow check valve 36. Further, the pipe 22 with the steam extraction valve 21, which is led out from the upper part of the chamber 33, is connected to the gas phase part in the reactor 1 through a reactor separation cooling system. Therefore, the upper part of the chamber 33 and the gas phase part of the nuclear reactor 1 are connected. Further, a pipe 39 provided with an on-off valve 38 is provided at the upper part of the chamber 33, and the tip thereof is connected to the spent fuel storage pool 28.

In the chamber 33, as shown in FIG. 2, a staggered liquid level gauge 40 is provided along the longitudinal direction of the chamber 33. Further, as shown in FIG. 3, a window 41 covered with tempered glass is provided on the side surface of the chamber 33 facing the staggered liquid level gauge 40, and the staggered liquid is passed through the window 41 from the outside of the chamber 33. The surface meter 40 can be visually observed. The staggered liquid level gauge 40 is red on the gas phase and black on the liquid phase. Therefore, the water surface L is visible from a distance. And this visual observation is also possible from the outside of the door of the large entrance of the reactor building and from the emergency exit.

Further, as shown in FIG. 2, an ultrasonic level meter 42 is provided in the upper part of the chamber 33, and can emit ultrasonic waves toward the water surface L in the chamber 33 and receive reflected waves from the water surface L. It is like that. The ultrasonic level meter 42 is used for supplying power to the instrument and measuring the level signal so that the water level of the reactor 1 can be measured and monitored at an intermediate position outside the central door of the large entrance of the reactor building. The equipment is pulled out to the above position, and the water level of the nuclear reactor 1 is checked in an emergency.

Furthermore, a TDR level meter (time domain reflect) having a special cable in which a core wire 43b is provided in a cylindrical electric conduit 43a having no bottom, such as a coaxial cable, from the upper part to the lower part in the chamber 33. Meter) 43 is provided.

As shown in FIG. 4, when the TRD level meter 43 has a positive electrode connected to the core wire 43b and a negative electrode connected to the conduit 43a to cause a pulse current to flow, the pulse current that has flowed to the core wire 43b flows into the conduit 43a. It is reflected by the inner water surface L, returns through the conduit 43a, and measures the time for returning to the instrument after emitting this pulse current, calculating the distance, and measuring the water level in the chamber 33. Yes. Similarly to the ultrasonic level meter 42, the TDR level meter 43 is provided with a power source and devices so that measurement can be performed at an intermediate position outside the central door of the large building entrance of the reactor building.

Further, an exhaust port 44 having a plug that can be opened and closed is provided at the top of the chamber 33, and a water supply port 45 having a plug that can be opened and closed is provided at the bottom.

In the first embodiment, three types of staggered liquid level meter 40, ultrasonic level meter 42, and TDR level meter 43 are provided as means for measuring the water level as described above. Some types of water level measuring means may be provided.

Next, the water level in the nuclear reactor 1 is monitored by the water level measuring means, and when the water level becomes low, the following injection operation is performed.

First, the overflow check valve 32, the steam discharge valve 21 and the overflow check valve 36 in the pipes 19, 22, and 37 of the chamber 33 with the reactor 1 are closed, and the chamber 33 and the reactor 1 are disconnected. Thereafter, the opening / closing valve 34 of the pipe 35 is opened, and water is poured into the chamber 33 from the makeup water tank 20 connected to the end of the pipe 35. The water injection is not limited to the makeup water tank 20, and a fire hose (not shown) may be connected to the end of the pipe 35. At that time, the open / close valve 38 of the upper pipe 39 of the chamber 33 is closed, and the stopper of the exhaust port 44 of the chamber 33 is opened, and water is injected while air is released.

When the chamber 33 becomes full of water due to the water injection, water overflows from the exhaust port 44, so that it is known that water is full and the water injection is stopped. Thereafter, the plurality of overflow check valves 32 and the steam extraction valve 21 of the pipes 19 and 22 are opened. Thereby, a part of the water in the chamber 33 enters the reactor 1 by its own weight through the pipes 19 and 14, and the reactor 1 is kept until the water in the chamber reaches the same level as the lowered water level of the reactor 1. Get inside. By repeating these operations, water is injected into the nuclear reactor 1 through the chamber 33.

Moreover, it can replace with the water injection to the reactor 1 from the chamber 33, and can also inject into the spent fuel storage pool 28. FIG.

That is, after the chamber 33 is filled with water, the on-off valve 38 of the pipe 39 can be opened and water can be poured into the spent fuel storage pool 28 using the pipe 39.

Further, in place of the first embodiment, a plurality of rectangular parallelepiped water injection tanks are installed in a possible space inside the wall of the upper floor of the reactor building, and the gravity of water is transferred from these water injection tanks to the chamber 33. Then, the water can be once poured into the nuclear reactor 1 and the spent fuel storage pool 28 by the above method.

DESCRIPTION OF SYMBOLS 1 Reactor 2 Main steam pipe 3 Turbine 4 Condenser 5 Condensate pump 6 Feed water heater 7 Feed water header 8 Steam relief safety valve 9 Pressure suppression chamber 10 Steam turbine
DESCRIPTION OF SYMBOLS 11 Pump 12 Condensate storage tank 13 Instrument 14 Instrumentation pipe 15 Condensation tank 16 Reference pressure pipe 17 Water level pressure pipe 18 Differential pressure gauge 19 Pipe 20 Supply water tank 21 Steam extraction valve 22 Pipe 24 Reactor containment vessel 25 Water supply check valve 26 Water check valve 27 Branch joint 28 Spent fuel storage pool
32 Overflow check valve 33 Chamber
34 On-off valve 35 Piping 36 Overflow check valve 37 Piping
38 On-off valve 39 Piping
40 Staggered liquid level gauge 41 Window
42 Ultrasonic level meter 43 TDR level meter
44 Exhaust port 45 Water supply port

Claims (8)

In the method of measuring the water level in the reactor in case of an emergency such as power loss,
A cylindrical sealed chamber having approximately the same height and approximately the same longitudinal length as the nuclear reactor is provided in advance,
A tube obtained by branching an instrumentation tube led out from the reactor is connected to the lower portion of the chamber to connect the liquid phase portion of the reactor and the chamber, and the upper portion of the chamber and the reactor The gas phase part is connected by piping, and the water level in the chamber is always the same as the water level of the reactor,
A staggered liquid level gauge is provided in the longitudinal direction in the chamber, a transparent tempered glass window is provided on the side of the chamber at a position facing the liquid level gauge, and a staggered liquid level gauge is inserted through the window of the chamber. The reactor water level measurement method in an emergency, characterized in that the reactor water level is measured visually. In the method of measuring the water level in the reactor in case of an emergency such as power loss,
A cylindrical sealed chamber having approximately the same height and approximately the same longitudinal length as the nuclear reactor is provided in advance,
A tube obtained by branching an instrumentation tube led out from the reactor is connected to the lower portion of the chamber to connect the liquid phase portion of the reactor and the chamber, and the upper portion of the chamber and the reactor The gas phase part is connected by piping, and the water level in the chamber is always the same as the water level of the reactor,
An ultrasonic emission device is provided at the top of the chamber, and an ultrasonic wave level measurement device provided outside the reactor containment vessel is used to emit ultrasonic waves into the chamber to measure the water level in the chamber. , Reactor water level measurement method in emergency. In the method of measuring the water level in the reactor in case of an emergency such as power loss,
A cylindrical sealed chamber having approximately the same height and approximately the same vertical length as the nuclear reactor is provided in advance, and a tube obtained by branching the instrumentation tube derived from the nuclear reactor into a T-shape is provided at the lower portion of the chamber. The reactor is connected to connect the liquid phase part of the reactor and the chamber, and the upper part of the chamber and the gas phase part of the reactor are connected by a pipe so that the water level in the chamber is always kept in the reactor. Same as the water level of
A coaxial cable-like special cable having a core wire provided in a pipe made of an electrical conductor in the longitudinal direction is provided in the chamber, and a TDR measuring instrument provided outside the reactor containment vessel is connected to the special cable. A pulse wave is emitted from a measuring instrument to a special cable in the chamber, and the distance is measured from the arrival time of the reflected wave of the pulse wave, thereby measuring the water level in the chamber. Of reactor water level in Japan. In a device that measures the water level in a nuclear reactor in case of an emergency such as power loss,
A cylindrical sealed chamber having approximately the same height and approximately the same vertical length as the nuclear reactor is provided in advance, and a tube obtained by branching the instrumentation tube derived from the nuclear reactor into a T-shape is provided at the lower portion of the chamber. The reactor is connected to connect the liquid phase part of the reactor and the chamber, and the upper part of the chamber and the gas phase part of the reactor are connected by piping, and the water level in the chamber is always kept in the reactor. Same as water level,
In the chamber, a staggered liquid level gauge is installed in the longitudinal direction, a transparent tempered glass window is provided on the side of the chamber facing the liquid level gauge, the power loss of the reactor and the stop of cooling water supply, etc. In an emergency, the reactor water level measuring device in an emergency, wherein the water level of the reactor can be measured by visually observing a staggered liquid level gauge through the window of the chamber. In a device that measures the water level in a nuclear reactor in case of an emergency such as power loss,
A cylindrical sealed chamber having approximately the same height and approximately the same vertical length as the nuclear reactor is provided in advance, and a tube obtained by branching the instrumentation tube derived from the nuclear reactor into a T-shape is provided at the lower portion of the chamber. The reactor is connected to connect the liquid phase part of the reactor and the chamber, and the upper part of the chamber and the gas phase part of the reactor are connected by a pipe so that the water level in the chamber is always kept in the reactor. Same as the water level of
An ultrasonic emission device is provided at the top of the chamber, and an ultrasonic water level measurement device provided outside the reactor containment vessel is used to emit ultrasonic waves into the chamber so that the water level in the chamber can be measured. A reactor water level measurement device in an emergency. In a device that measures the water level in a nuclear reactor in case of an emergency such as power loss,
A cylindrical sealed chamber having approximately the same height and approximately the same vertical length as the nuclear reactor is provided in advance, and a tube obtained by branching the instrumentation tube derived from the nuclear reactor into a T-shape is provided at the lower portion of the chamber. The reactor is connected to connect the liquid phase part of the reactor and the chamber, and the upper part of the chamber and the gas phase part of the reactor are connected by a pipe so that the water level in the chamber is always kept in the reactor. Same as the water level of
A coaxial cable-like special cable having a core wire provided in a pipe made of an electrical conductor in the longitudinal direction is provided in the chamber, and a TDR measuring instrument provided outside the reactor containment vessel is connected to the special cable. A pulse wave was emitted from the measuring instrument to the special cable in the chamber, and the distance was measured from the return time of the reflected wave of the pulse wave to the TDR measuring instrument, thereby making it possible to measure the water level in the chamber. Reactor water level measuring device in emergency. In the device according to any one of claims 4 to 6,
For the exhaust or drainage provided at the upper or lower part of the chamber, the pipes branched from the instrumentation pipe and the pipes connecting the upper part of the chamber and the gas phase part of the reactor are closed. Open the stopper of the opening and inject cold water into the chamber to fill the chamber with water,
Then, by closing the stopper and opening the valves, the water in the chamber enters the reactor until it reaches the same level as the lowered reactor water level, and these steps are repeated several times. A method of pouring water into a nuclear reactor in an emergency, characterized by injecting cold water into the nuclear reactor. In the device according to any one of claims 4 to 6,
For the exhaust or drainage provided at the upper or lower part of the chamber, the pipes branched from the instrumentation pipe and the pipes connecting the upper part of the chamber and the gas phase part of the reactor are closed. Open the stopper of the opening and inject cold water into the chamber to fill the chamber with water,
Thereafter, the stopper is closed, cold water is poured from the chamber into the spent nuclear fuel storage pool, and these steps are repeated a plurality of times, and the method for pouring water into the spent nuclear fuel storage pool in an emergency is characterized.

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