JPH1090476A - Fresh fuel storage room - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent excess temperature rise and exposure of workers during storing fresh fuel assemblies by providing a removable radiation shield lid and heat exhaust device in the fresh fuel storage room. SOLUTION: Carry-in and carry-out of fresh fuel assemblies 10 in a fresh fuel storage room 9 is done by opening and closing a removable shielding lid 11 at every time. The shielding lid 11 does not leak radiation outside the fresh fuel storage room 9 owing to the sufficient radiation shield function even during storing advanced fresh fuel assemblies emitting much radiation or at the time of incidental failure of fresh fuel assemblies 10 and resulting large emission of radiation. The larger decay heat generated by the advanced fresh fuel assemblies 10 than before is emitted in the fresh fuel storage room 9. As the cooling air of air conditioner flows via air conditioner main pipe 14 in supply side →discharge side connection duct 13 → discharge side ventilation outlet 12 →fresh fuel storage room 9 → suction side ventilation outlet 15 → suction side connection duct 16 → recovery side air conditioner main pipe 17 and returns to the air conditioner, excess temperature rise in the fresh fuel storage room 9 and the advanced fresh fuel assemblies 10 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a new fuel storage for temporarily storing new fuel carried into a nuclear power plant as new fuel.

[0002]

2. Description of the Related Art As shown in a partially cutaway perspective view in FIG. 12, a new fuel storage installed in a nuclear power plant has a new fuel storage 1 which is an operation control floor in a reactor building of a nuclear power plant. The new fuel assembly 3 is constructed so as to be open to the surface 2 and carried in and out of the new fuel storage 1.
And the upper lid 4 is closed. The new fuel storage 1 is located near a fuel pool 7 that communicates with a reactor well 5 of a reactor building and stores a spent fuel assembly 6 and the like filled with cooling water.

The new fuel assembly 3 carried into the reactor building for power generation is temporarily stored in a new fuel storage rack 8 in the new fuel storage 1. Generates decay heat due to its nuclear decay. This decay heat is transferred to the walls and the like in the new fuel storage 1 by natural circulation by convection in which the air warmed by the heat rises and is exhausted.

[0004]

When a new fuel assembly 3 made of a conventional uranium oxide is stored in a new fuel storage 1, heat generated by decay heat is discharged by natural circulation without hindrance. Since the radiation emitted from the new fuel assembly 3 is small also on the operation floor 2, there is no need to particularly consider countermeasures against exposure to workers.

However, a newly developed fuel (a mixed oxide fuel of uranium oxide and plutonium oxide (MOX
Some of the new fuel assemblies according to the present invention have higher spontaneous fission and higher decay heat and radiation dose than the conventional new fuel assembly 3. In the case where the storage is performed at 1, it is necessary to take measures against the exhaust heat treatment and the exposure of the operation operation floor 2 to workers.

In the event that the new fuel assembly 3 is damaged during storage or storage work, a problem arises in that an abnormal radiation dose is exhibited and radioactive contaminants diffuse into the reactor building.

It is an object of the present invention to provide a new fuel storage with a radiation shielding cover and a heat exhaust device to store a new fuel assembly with spontaneous fission, or to damage the new fuel assembly. An object of the present invention is to provide a new fuel storage that prevents an excessive rise in temperature and prevents workers from being exposed to the operation floor of a reactor building even when the radiation dose increases.

[0008]

In order to achieve the above object, a new fuel storage according to the first aspect of the present invention temporarily stores a new fuel assembly carried in as new fuel before use in a nuclear reactor. In a new fuel storage that is surrounded by walls around the perimeter and bottom and the top opening is closed by a removable top lid,
A storage rack for storing the new fuel assembly is installed therein, and the upper lid for closing the opening is a shielding lid for shielding the radiation emitted by the stored new fuel assembly.

When the new fuel assembly emits high radiation, since the opening of the new fuel storage is closed by the shielding lid for shielding the radiation, radiation does not leak from inside the new fuel storage and the operation floor is operated. Exposure to workers working on the surface is prevented.

A new fuel storage according to a second aspect of the present invention is characterized in that a wall surrounding the periphery and the bottom is provided with a ventilation hole penetrating therethrough, and the ventilation hole is provided with a connection duct connected to an air conditioner. . Cooling air is circulated from the air-conditioning system via a connection duct connected to a ventilation hole provided through the wall, so the decay heat generated by the new fuel assemblies stored in the new fuel storage is generated by the cooling air. Heat is exhausted.

[0011] The new fuel storage according to the third aspect of the present invention is characterized in that the lower part is a discharge side vent, and the upper part is a suction side vent. . The temperature of the low-temperature cooling air flowing from the lower discharge port in the new fuel storage becomes higher due to the decay heat generated by the new fuel assemblies. The cooling efficiency in the new fuel storage can be obtained because the fuel is discharged from the suction side vent.

According to a fourth aspect of the present invention, there is provided a new fuel storage, wherein a connection duct is provided which penetrates a shielding lid for closing an upper opening and which is connected to an air conditioner whose leading end is a vent in the new fuel storage. It is characterized by the following. Cooling air from the air conditioner flows into the new fuel storage through a connection duct that penetrates the shielding lid, and is discharged from another connection duct that penetrates the shielding lid, generating decay heat generated by the new fuel assembly. Discharge heat.
Therefore, a large-scale facility construction is not required, and it can be easily adopted for an existing new fuel storage.

According to a fifth aspect of the present invention, there is provided a new fuel storage, wherein a cooling air conditioner having a fan and a heat exchanger is connected to a connection duct connected to the ventilation port to form a closed loop. The decay heat generated by the new fuel assemblies stored in the new fuel storage is exhausted by the heat exchanger of the cooling air conditioner through the cooling air, and the cooling air conditioner is connected to the new fuel storage and the connection. Since the closed loop is formed together with the duct, the cooling air does not leak to the outside.

According to a sixth aspect of the present invention, there is provided a new fuel storage system, wherein a plurality of systems are provided with a ventilation port and a connection duct connected to the ventilation port, each of which is connected to an independent air conditioning facility or a cooling air conditioning apparatus. Features. Since the air conditioning system that cools the inside of the new fuel storage with the air conditioning equipment or the cooling air conditioner is multiplexed, the reliability of the air conditioning equipment or the cooling air conditioner against failure is high.

According to a seventh aspect of the present invention, a new fuel storage is connected to a system in which a connection duct connected to an air vent is connected to an air conditioner, and a closed-loop cooling air conditioner including a fan and a heat exchanger. And a system. The air conditioning system that cools the multiplexed new fuel storage compartment combines cooling and air conditioning equipment with different air conditioning equipment and cooling air conditioning equipment mechanisms. High reliability.

[0018] The new fuel storage according to the invention described in claim 8 is characterized in that a refrigerant passage is provided in a lining of a wall surrounding the periphery and the bottom to flow the refrigerant. By appropriately flowing the refrigerant through the refrigerant passage provided in the lining of the new fuel storage, the inside of the new fuel storage is cooled by natural convection without contaminating the refrigerant.

According to a ninth aspect of the present invention, the new fuel storage is provided with an internal thermometer and a temperature controller, and a valve is inserted into a connection duct connected to an air conditioner to measure the temperature in the new fuel storage from the measured temperature. The internal temperature is controlled by operating a valve of the connection duct.

The temperature inside the new fuel storage is measured by an internal thermometer. If the temperature is higher than a set value, a valve inserted in the connection duct is opened to supply and exhaust cooling air to generate a new fuel assembly. Discharge decay heat. When the internal temperature is lower than the set value, the valve is closed to stop the supply and exhaust of the cooling air to control the temperature in the new fuel storage.

A new fuel storage according to the invention according to claim 10 is provided with an internal thermometer and a temperature controller, and is provided with a fan and a heat exchanger based on the measured temperature in the new fuel storage to form a closed-loop cooling air conditioner. The internal temperature is controlled by operating a fan in the apparatus. The exhaust heat of the decay heat generated by the new fuel assembly stored in the new fuel storage and the internal temperature control are controlled by the correspondence between the internal temperature measured by the internal thermometer and the set value of the air conditioning system formed in a closed loop. This is performed by controlling the operation of the fan in the cooling air conditioner.

[0020] The new fuel storage according to the invention of claim 11 is provided with an internal radiation monitor and a selection controller, inserts a valve into an exhaust side connection duct connected to a vent, and branches off from the upstream side of the valve. A connection duct having a valve connected to the radioactive waste treatment system pipe is provided, and the treatment system is selected based on the measured radiation amount in the new fuel storage.

The radiation dose in the new fuel storage is measured by the internal radiation monitor, and when the set value is exceeded, the selection controller closes the valve inserted in the exhaust side connection duct and contains radioactive contaminants. Prevents cooling air from returning into the air conditioning system. In addition, by opening the valve inserted in the connection duct connected to the radioactive waste treatment system piping, the decay heat generated by the new fuel assembly in the new fuel storage is exhausted, and cooling containing radioactive contaminants is performed. Send air to radioactive waste treatment facility.

According to a twelfth aspect of the present invention, a new fuel storage is provided with an internal radiation monitor and a selection controller.
By providing a plurality of different systems of the air conditioning system connected to the connection duct connected with the valve and the air conditioning mechanism of the closed loop cooling air conditioner,
A different air conditioning mechanism system is selected according to the measured radiation dose in the new fuel storage.

When the radiation dose in the new fuel storage exceeds a set value, the selection controller selects a system in the closed-loop cooling air-conditioning system by operating the valve and operating the fan to control the cooling air containing radioactive contaminants. Prevents the air from flowing into the air conditioning system. In addition, since the decay heat generated by the new fuel assembly is exhausted and the cooling air containing radioactive contaminants is circulated and cooled in a closed loop cooling air conditioning system, radioactive contaminants are Do not leak to

According to a thirteenth aspect of the present invention, the new fuel storage is characterized in that a shielding lid for closing an upper opening is provided with a shielding heat radiation hole for radiating internal heat and shielding radiation. The decay heat generated by the new fuel assembly stored in the new fuel storage is exhausted to the outside by natural convection and the shielding heat radiation holes in the new fuel storage. The radiation emitted by the new fuel assembly during storage is shielded by the shielding lid and the shielding heat radiation hole and does not leak to the outside.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. Note that the same components as those of the above-described conventional technology are denoted by the same reference numerals, and detailed description is omitted. The first embodiment relates to claim 1, and as shown in a partially cutaway perspective view of FIG. 1, the new fuel storage 9 is constructed so as to open to the operation floor 2 of the reactor building. Is provided with a new fuel storage rack 8 for storing a new fuel assembly 10.

In addition, radiation emitted from the new fuel assembly 10 stored in the new fuel storage 9 does not affect the operator on the operation floor 2 at the opening.
Removable shielding lid with sufficient thickness and radiation shielding function
It is configured to be closed at 11.

Next, the operation of the above configuration will be described. In the new fuel storage 9, the loading and unloading of the new fuel assembly 10 is performed at the upper opening, and the removable cover 11 is opened and closed each time. The shielding lid 11 is used when the new fuel assembly 10 that emits more radiation than the conventional new fuel assembly 3 is stored, or when the new fuel assembly 3 or the new fuel assembly that is stored is stored. When the radiation is damaged and more radiation is emitted than in the normal state, a sufficient radiation shielding function prevents the radiation from leaking out of the new fuel storage 9.

Therefore, on the operation floor 2 inside the reactor building where the new fuel storage 9 is constructed, the exposure of workers increases even if no special measures are taken to prevent exposure as in the past. As there is no work environment and safety for workers are improved.

The second embodiment relates to claims 2 and 3, and its structure is shown in a partially cutaway perspective view in FIG. The description of the same components as those in the first embodiment will be omitted, together with the operation thereof. A discharge side ventilation port 12 is provided at the lower part through the wall of the new fuel storage 9, and is connected to a supply side air conditioner mother pipe 14 connected to an air conditioner (not shown) via a discharge side connection duct 13.

Similarly, a suction-side ventilation port 15 is provided at the upper part through the wall, and is connected to a collection-side air conditioning equipment mother pipe 17 via a suction-side connection duct 16 (see FIG. 1). Claims 2 and 3).

Next, the operation of the above configuration will be described. New fuel storage rack 8 installed in new fuel storage 9
When the new fuel assembly 10 that emits more decay heat and radiation than the conventional new fuel assembly 3 is stored, the decay heat generated by the new fuel assembly 10 is stored in the new fuel storage. 9 is released.

At this time, unlike the new fuel assembly 3 of the related art, the new fuel assembly 10 generates a large amount of decay heat.
Exhaust heat is not enough. However, the cooling air generated in the air conditioning equipment (not shown) is blown into the new fuel storage 9 from the lower discharge side ventilation port 12 through the supply side air conditioning equipment mother pipe 14 and the discharge side connection duct 13.

The cooling air passes between the new fuel assemblies 10 and removes the decay heat released by the new fuel assemblies 10 to increase the temperature.
Is sucked into the suction side ventilation port 15 at the upper part of the air conditioner, and returns to the air conditioning equipment via the suction side connection duct 16 and the collection side air conditioning equipment mother pipe 17. As a result, in the new fuel storage 9 and the new fuel assembly 10 being stored, the temperature is not excessively increased because the new fuel assembly 10 is cooled by the cooling air blown out from the discharge-side vent 12.

In the new fuel storage 9, the low-temperature cooling air blown out from the discharge-side vent 12 provided at the lower portion is heated by the new-type new fuel assembly 10 to a high temperature, and rises to the upper portion. At the suction side vent hole 15. Thereby, even when the amount of cooling air is small, the cooling air passes through the new fuel assembly 10 due to the natural convection due to the temperature difference, so that an effective cooling effect can be obtained.

In the air conditioner, the high-temperature air that has flowed in from the recovery-side air conditioner main pipe 17 is always cooled by a refrigerator (not shown), and is again sent out from the supply-side air conditioner main pipe 14 as cooling air. You are. Furthermore, the shielding lid 11 does not leak the radiation to the outside of the new fuel storage 9 due to a sufficient radiation shielding function even when the new fuel assembly 10 that emits a large amount of radiation is stored.

The third embodiment relates to claim 4 and the structure thereof is shown in a partially cutaway perspective view in FIG. The description of the same components as those of the above-described first and second embodiments will be omitted together with the operation thereof.

In the new fuel storage 9, a new fuel storage rack 8 is installed to store the new fuel assembly 10. The new fuel assembly 10 is stored in a part of the shielding lid 18 of the shielding lid 11 provided at the upper opening. One through-hole 19 is formed, and one of the through-holes 19 has a discharge-side ventilation port 12 at a lower end in the new fuel storage 9 and a discharge-side connection duct 13 whose other end is connected to a supply-side air-conditioning facility mother pipe 14. Through.

The other through-hole 19 is provided with a front end serving as a suction-side ventilation port 15 in the upper part of the new fuel storage 9 and a suction-side connection duct 16 whose other end is connected to a recovery-side air-conditioning facility mother pipe 17. It has a configuration.

Next, the operation of the above configuration will be described. The decay heat generated by the new fuel assembly 10 stored in the new fuel storage rack 8 installed in the new fuel storage 9 is connected to the discharge side connection in the new fuel storage 9 via the supply-side air conditioner mother pipe 14. At the tip of the duct 13, it is cooled by the cooling air blown out from the discharge side ventilation port 12 below the new fuel storage 9.

The air that has become high in temperature due to the decay heat of the new fuel assembly 10 rises in the new fuel storage 9, and then flows through the suction-side air vent 15, which is the tip of the suction-side connection duct 16, to the suction-side connection. Via the duct 16, the recovery-side air-conditioning system main pipe 17
And returns to the air conditioner (not shown).

The operation and effects of the third embodiment are the same as those of the second embodiment.
A shielding lid for closing an opening on the upper surface of the new fuel storage 9
18, a simple structure is provided in which the discharge-side connection duct 13 and the suction-side connection duct 16 are provided from above the operation operation floor 2.
For this reason, no special construction work is required for the new fuel storage 9, and the new fuel storage 9 can be easily implemented for the existing new fuel storage 1.

The fourth embodiment relates to claim 5, and its structure is shown in a partially cutaway perspective view in FIG. The description of the same components as those of the above-described first and second embodiments will be omitted together with the operation thereof. The new fuel storage 9 has a discharge-side connection duct 13 connected to a discharge-side ventilation port 12 provided at a lower portion of the wall thereof, and a suction-side connection duct 16 connected to a suction-side ventilation port 15 also provided at an upper portion of the wall. Between,
A closed loop is configured by connecting a cooling air conditioner including the heat exchanger 20 and the fan 21.

Next, the operation of the above configuration will be described. The temperature of the air in the new fuel storage 9 rises due to the decay heat generated by the new fuel assembly 10 stored in the new fuel storage rack 8 in the new fuel storage 9, but the hot air is used for cooling. By the operation of the air conditioner, the fan 21 is forcibly sucked into the suction-side connection duct 16 from the suction-side ventilation port 15.

The high-temperature air is sent from the fan 21 to the heat exchanger 20 and exchanges heat with the cold water 22 to become low-temperature cooling air.
After returning to the fresh fuel storage 9 through the discharge side ventilation port 12 via the discharge side connection duct 13, the inside is cooled. At this time, since the closed air-conditioning system for the new fuel storage 9, the fan 21 and the heat exchanger 20 has a closed loop formed with each connection duct, radioactive contaminants flow out of the cooling air-conditioning system. Since there is no such thing, the safety is high and the cooling effect is great.

The fifth embodiment relates to claim 6 or claim 7, and its structure is shown in a partially cutaway perspective view in FIG.
The description of the same components as those of the above-described first and second embodiments will be omitted together with the operation thereof. The new fuel storage 9 is multiplexed by providing a plurality of independent systems in the cooling system, and FIG. 5 shows an example in which two systems of the second embodiment are provided.

The first cooling system includes a discharge-side connection duct 13 connected to the discharge-side ventilation port 12 provided in the new fuel storage 9, and a suction-side connection connected to the supply-side air conditioning equipment main pipe 14 and the suction-side ventilation port 15. It is composed of a duct 16 and a recovery-side air conditioning facility mother pipe 17.

Further, the second cooling system includes a separate discharge side connection duct 13a connected to the separate discharge side vent 12a, a separate supply side air conditioner main pipe 14a, and a separate suction side vent. 15a
The first system and the second system are connected to independent air conditioning equipment, respectively, and are constituted by a separate suction side connection duct 16a connected to the air conditioning system and a separate recovery air conditioning equipment main pipe 17. I have.

Further, the independent plural cooling systems may be multiplexed by a closed loop in which the cooling air conditioner including the heat exchanger 20 and the fan 21 shown in the fourth embodiment is connected (claim 6).

The operation of the above configuration is as follows. By multiplexing a plurality of cooling systems, even if a part of the cooling system including the air conditioning equipment or the cooling air conditioner breaks down,
Since the decay heat generated by the new fuel assembly 10 in the new fuel storage 9 can be discharged without any trouble by another sound cooling system, reliability and safety are improved.

Further, as a modified example, a plurality of independent cooling systems are each configured by combining the air conditioning equipment of the second embodiment and the cooling air conditioner of the fourth embodiment with different cooling devices. (Claim 7). The effect of this configuration is to multiplex the cooling system into multiple systems,
Since different cooling devices are combined, a high reliability can be obtained because a failure due to the configuration of the cooling device does not propagate to other cooling devices.

The sixth embodiment relates to claim 8, and its structure is shown in a partially cutaway perspective view of FIG. The description of the same components as those in the first embodiment will be omitted, together with the operation thereof. The new fuel storage 23 is provided with a lining 24 on the inside of the wall and the bottom.A coolant passage 25 is formed outside the lining 24, and a coolant inlet 26 is provided at the bottom of the coolant passage 25. A refrigerant outlet 27 is attached to the upper part of the passage 25.

Further, the refrigerant inlet 26 and the refrigerant outlet 27
Is connected to an air conditioner or a cooling air conditioner (not shown) to flow cooling air as a refrigerant, or to a cold water source (not shown) to flow cold water 22 of the refrigerant. The effect of the above configuration is that the temperature of the air in the new fuel storage 9 rises due to the decay heat generated by the new fuel assembly 10 stored in the new fuel storage rack 8 in the new fuel storage 23. Is circulated in the new fuel storage 9 by natural convection.

At this time, since the wall and bottom lining 24 are cooled by the refrigerant flowing through the refrigerant passage 25, the new fuel storage 9
The high temperature air is cooled by touching the surface of the lining 24, whereby natural convection is activated and the decay heat generated by the new fuel assembly 10 is discharged by the refrigerant through the lining 24. Get heated. Further, the amount and temperature of decay heat exhausted in the new fuel storage 9 can be controlled by the type, temperature and flow rate of the refrigerant flowing through the refrigerant passage 25.

Since there is no projection on the inner surface of the lining 24 inside the new fuel storage 23, the inside can be used effectively and there is no circulation with the outside. Even if the radioactive contaminants are damaged and released into the new fuel storage 23, the radiation does not leak to the outside. Therefore, there is no radiation exposure.

The seventh embodiment relates to claim 9 and the structure is shown in a partially cutaway perspective view in FIG. The description of the same components as those of the above-described first and second embodiments will be omitted together with the operation thereof. The main structure of the new fuel storage 9 is the same as that of the second embodiment shown in FIG.
And a temperature controller 29 is connected to the internal thermometer 28.

Further, a supply side valve 30 is provided in the discharge side connection duct 13 connected to the discharge side ventilation port 12, and a suction side ventilation port 15 is provided.
The recovery side valve 31 is inserted in the suction side connection duct 16 connected to the suction port, and both valves 30, 31 are connected to the temperature controller 29.

Next, the operation of the above configuration will be described. The cooling air that has flowed into the new fuel storage 9 from the discharge side vent 12 through the discharge side connection duct 13 and the supply side valve 30 from the air conditioning equipment (not shown) cools the new fuel assembly 10 stored inside. Then, the fuel flows out from the suction-side ventilation port 15 via the suction-side connection duct 16 and the recovery-side valve 31, and the decay heat generated by the new fuel assembly 10 is exhausted.

At this time, the temperature inside the new fuel storage 9 is measured by the internal thermometer 28 and output to the temperature controller 29. The temperature controller 29 controls the temperature inside the new fuel storage 9 according to the internal temperature. The supply-side valve according to a preset set value
The cooling air flow rate is controlled by opening and closing 30 and the recovery side valve 31.

Thus, the temperature in the fresh fuel storage 9 is appropriately controlled. That is, when the new decay fuel assembly 10 generates a large amount of decay heat, the internal temperature increases,
When the set value is exceeded, the valves 30 and 31 are opened, and the amount of heat exhausted is increased by flowing cooling air. When the internal temperature drops below the set value, the valves 30 and 31 are closed to stop the flow of the cooling air, and heat is discharged by natural circulation of the air in the new fuel storage 9. .

As a modification of the above, the supply-side valve
30 and the recovery valve 31 are used as regulating valves, and the new fuel storage 9
By adjusting the opening degree by the temperature controller 29 according to the temperature in the inside, the temperature in the new fuel storage 9 can be controlled more accurately than when opening and closing the supply-side valve 30 and the recovery-side valve 31. it can. Thereby, the temperature in the new fuel storage 9 is lowered unnecessarily, and the temperature of the new fuel storage 9 is appropriately controlled without supplying excessive cooling air. The economic effect is improved because it is reduced.

The eighth embodiment relates to claim 10, and the structure is shown in a partially cutaway perspective view of FIG. The description of the same components as those of the above-described first, second, and fourth embodiments will be omitted together with the operation thereof.

The main structure of the new fuel storage 9 is the same as that of the fourth embodiment shown in FIG.
A cooling loop air conditioner comprising a heat exchanger 20 and a fan 21 is connected between the discharge side connection duct 13 connected to the suction side connection duct 16 connected to the suction side ventilation port 15 to form a closed loop. I have. Further, an internal thermometer 28 is provided in the new fuel storage 9.
And a temperature controller 29 is connected to the internal thermometer 28. The temperature controller 29 is connected to the fan 21.

Next, the operation of the above configuration will be described. The temperature in the new fuel storage 9 is measured by the internal thermometer 28 and output to the temperature controller 29. The temperature controller 29 controls the start and stop of the fan 21 of the cooling air conditioner according to the internal temperature of the new fuel storage 9. That is, the temperature controller 29 controls the operation of the fan 21 in accordance with a preset value of the temperature in the new fuel storage 9 measured by the temperature controller 29, so that the heat exchanger 20 and the new fuel storage The air flow rate circulating through the inside 9 is changed.

When the internal temperature exceeds a preset value, the temperature controller 29 activates the fan 21 to cool the new fuel storage 9. When the internal temperature becomes equal to or lower than the set value, the fan 21 is stopped, the cooling in the new fuel storage 9 is stopped, and the temperature is controlled.

The operation control of the fan 21 by the temperature controller 29 is performed not only by starting and stopping the fan 21 but also by changing the rotation speed to change the circulating air flow rate and increase or decrease the amount of exhaust heat of decay heat. Temperature control can be performed. Thereby, the temperature of the new fuel storage 9 is appropriately controlled, and the capacity of the cooling air conditioner is reduced, thereby improving the economic effect.

The ninth embodiment relates to claim 11, and the structure is shown in a partially cutaway perspective view in FIG. The description of the same components as those of the above-described first and second embodiments will be omitted together with the operation thereof.

The main structure of the new fuel storage 9 is the same as that of the second embodiment shown in FIG. 2, except that the recovery side valve 31 is inserted in the suction side connection duct 16 connected to the suction side vent 15. At the same time, a waste treatment meter duct 33 interposed with a waste treatment valve 32 is branched from the suction connection duct 16 on the upstream side of the recovery side valve 31.

The waste treatment meter duct 33 is connected to a radioactive waste treatment pipe 34, and the radioactive waste treatment pipe 34 is connected to a radioactive waste treatment facility (not shown). Further, an internal radiation monitor 35 is disposed inside the new fuel storage 9, and the internal radiation monitor 35 is connected to the recovery side valve 31 and the waste treatment system valve 32 via a selection controller 36. ing.

Next, the operation of the above configuration will be described. New fuel assembly stored in new fuel storage 9
The decay heat generated 10 flows in from the discharge side ventilation port 12 through the discharge side connection duct 13 from the supply side air conditioner mother pipe 14,
The heat is exhausted from the suction side ventilation port 15 through the suction side connection duct 16 and the collection side valve 31 by the cooling air flowing through the collection side air conditioner mother pipe 17.

In the event that the new fuel assembly 10 is damaged or abnormally high radiation is emitted, radioactive contaminants, together with the flow of the cooling air, flow into the suction side connection duct 16. Then, the air flows into the air-conditioning equipment (not shown) via the recovery-side air-conditioning equipment main pipe 17 and circulates.

However, when the high radiation is measured by the internal radiation monitor 35 and transmitted to the selection controller 36, the selection controller 36 closes the recovery side valve 31 and opens the waste treatment system valve 32. Radioactive contaminants are collected on the recovery side air conditioning equipment main pipe.
It does not flow to the air conditioning equipment via 17. As a result, the decay heat generated by the new fuel assembly 10 in the new fuel storage 9 is exhausted, and the cooling air containing radioactive contaminants is supplied to the suction side connection duct 16 and the waste treatment system. Via the duct 33, it is sent to a waste treatment facility (not shown).

As a result, in the waste treatment facility, the waste treatment of the cooling air is performed, so that the exhaust heat in the new fuel storage 9 is not hindered, and the circulation of the cooling air containing pollutants causes the new fuel storage 9 to be cooled. In addition, since the air conditioning system is not contaminated and there is no leakage to the outside, safety is improved.

The tenth embodiment relates to claim 12, and the structure is shown in a partially cutaway perspective view of FIG. The description of the same components as those in the first, second, and fifth embodiments will be omitted along with the operation thereof.

The new fuel storage 9 is provided with two air conditioning systems. The first air conditioning system is the same as that of the second embodiment shown in FIG. It is formed by providing a discharge side vent 12 connected to the discharge side connection duct 13 via the facility main pipe 14 and a suction side vent 15 connected to the suction side connection duct 16 via the recovery side air conditioning facility main pipe 17. . The discharge side connection duct 13 has a supply side valve 30.
The recovery side valve 31 is interposed between the suction side connection duct 16 and the suction side connection duct 16.

The second air-conditioning system is similar to the fourth embodiment shown in FIG. 4, and has a separate discharge-side connection duct 13a connected to the separate discharge-side vent 12a and a separate discharge-side connection duct 13a. A cooling air conditioner including a heat exchanger 20 and a fan 21 is provided between the suction side connection duct 16a and another system connected to the suction side ventilation port 15a to form a closed loop. Further, inside the new fuel storage 9, an internal radiation monitor 35 is arranged and connected to a selection controller 36. The selection controller 36 is connected to the supply-side valve 30, the recovery-side valve 31, and the fan 21. It is configured.

Next, the operation of the above configuration will be described. Normally, cooling air from an air conditioner (not shown), which is the first air conditioning system, is supplied into the new fuel storage 9 from the discharge side vent 12 to reduce the decay heat generated by the stored new fuel assembly 10. The heat is exhausted from the suction side vent 15.

If the new fuel assembly 10 is damaged or abnormally high radiation is emitted, the internal radiation monitor 35 measures the high radiation and transmits it to the selection controller 36. Is done. By a signal from the internal radiation monitor 35, the selection controller 36 performs an operation of closing the supply side valve 30 inserted in the discharge side connection duct 13 and the collection side valve 31 inserted in the suction side connection duct 16. Then, the fan 21 of the second air conditioning system is started.

As a result, radioactive contaminants contained in the cooling air in the new fuel storage 9 do not flow to the air conditioning equipment as the first air conditioning system, and no pollution occurs in the first air conditioning system. The decay heat generated by the new fuel assembly 10 in the new fuel storage 9 is exhausted by the heat exchanger 20 of the cooling air conditioner in the second air conditioning system. Since the second air-conditioning system is formed in a closed loop, radioactive contaminants contained in the cooling air do not leak to the outside, so that safety is improved.

The eleventh embodiment relates to claim 13, and the structure is shown in a partially cutaway perspective view of FIG. The description of the same components as those in the first embodiment will be omitted, together with the operation thereof.

The opening on the upper surface of the new fuel storage 9 is closed by a shielding lid 11 for shielding radiation from the inside, but part or all of the opening communicates with the air inside and outside the new fuel storage 9. However, the communication passage is bent with a labyrinth structure, and the shape is such that radiation from the new fuel assembly 10 stored inside does not pass through to the outside, closed by a shielding lid 38 with a shielding heat radiation hole 37 opened. And

According to the above configuration, the decay heat generated by the new fuel assembly 10 stored in the new fuel storage 9 is discharged to the outside by the natural convection in the new fuel storage 9 and the shield heat radiation hole 37. . At this time, the radiation emitted from the new fuel assembly 10 is shielded not only by the shielding lid 11 but also by the shielding lid 38 because of the bent communication path of the shielding heat radiation hole 37 for heat radiation. Operation floor of the reactor building 2
It does not expose workers who work in.

In each of the above embodiments,
Although the description has been given of the new fuel assembly 10 in which spontaneous fission is more active and the decay heat and the radiation dose are higher than those of the conventional new fuel assembly 3 as an example, the new fuel assembly 3 may be used for storage. This is particularly effective when the new fuel assemblies 3 and 10 are damaged or abnormally high radiation is emitted.

[0083]

As described above, according to the present invention, the opening is closed when storing a new fuel assembly having a higher spontaneous fission and a larger decay heat and radiation dose than the conventional new fuel assembly in the new fuel storage. Due to the shielding lid, it is possible to prevent the radiation of the new fuel assembly from exposing workers on the operation floor.

Further, the inside of the new fuel storage is forcibly cooled by the cooling air, the economy is improved by the temperature control operation, and the radioactive contamination is selected by selecting the air conditioning system and the radioactive waste facility at the time of high radiation emission. Safety is improved by stopping the contamination of the substance locally and preventing the spread of the contamination.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of a new fuel storage according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of a new fuel storage according to a second embodiment of the present invention.

FIG. 3 is a partially cutaway perspective view of a new fuel storage according to a third embodiment of the present invention.

FIG. 4 is a partially cutaway perspective view of a new fuel storage according to a fourth embodiment of the present invention.

FIG. 5 is a partially cutaway perspective view of a new fuel storage according to a fifth embodiment of the present invention.

FIG. 6 is a partially cutaway perspective view of a new fuel storage according to a sixth embodiment of the present invention.

FIG. 7 is a partially cutaway perspective view of a new fuel storage according to a seventh embodiment of the present invention.

FIG. 8 is a partially cutaway perspective view of a fresh fuel storage according to an eighth embodiment of the present invention.

FIG. 9 is a partially cut perspective view of a new fuel storage according to a ninth embodiment of the present invention.

FIG. 10 is a partially cut perspective view of a new fuel storage according to a tenth embodiment of the present invention.

FIG. 11 is a partially cutaway perspective view of a new fuel storage according to an eleventh embodiment of the present invention.

FIG. 12 is a partially cutaway perspective view of a new fuel storage in a conventional reactor building.

[Explanation of symbols]

1, 9, 23 ... new fuel storage, 2 ... operation floor, 3 ... new fuel assembly, 4 ... top lid, 5 ... reactor well, 6 ... spent fuel assembly, 7 ... fuel pool, 8 ... new Fuel storage rack, 10: New fuel assembly, 11, 18, 38: Shielding lid, 12: Discharge side vent, 12a: Separate discharge side vent, 13: Discharge side connection duct, 13a: Separate discharge Side connection duct, 14 ... supply side air conditioning equipment main pipe, 14a ... separate supply side air conditioning equipment main pipe, 15 ...
Suction-side vent, 15a: Separate suction-side vent, 16: Suction-side connection duct, 16a: Separate, suction-side connection duct, 17: Recovery-side air conditioning equipment mother pipe, 17a: Separate, collection-side air conditioning Mother tube, 19
… Through holes, 20… heat exchangers, 21… fans, 22… cold water, 24…
Lining, 25 ... refrigerant passage, 26 ... refrigerant inlet, 27 ... refrigerant outlet, 28
... internal thermometer, 29 ... temperature controller, 30 ... supply side valve, 31 ... collection side valve, 32 ... waste treatment side valve, 33 ... waste treatment side connection duct, 34 ... waste treatment main pipe, 35 ... Internal radiation monitor, 36
… Selection controller, 37… Shield heat radiation hole.

Claims (13)

[Claims] 1. A new fuel storage which temporarily stores a new fuel assembly carried in as a new fuel before use for a nuclear reactor and which is surrounded by a wall around a periphery and a bottom and whose upper opening is removed by a removable top cover. 3. The new fuel storage according to claim 1, wherein a storage rack for storing the new fuel assembly is installed therein, and an upper lid for closing an opening is a shielding lid for shielding radiation emitted by the stored new fuel assembly. 2. The fresh fuel storage according to claim 1, wherein a ventilation duct is provided through a wall surrounding the periphery and the bottom part, and a connection duct for connecting to an air conditioner is provided in the ventilation hole. New fuel storage. 3. In the new fuel storage, a lower portion is provided at a discharge side vent at a lower portion of the vent which penetrates a wall surrounding the periphery and the bottom,
3. The new fuel storage according to claim 2, wherein the upper part is a suction side vent. 4. The new fuel storage, wherein a connection duct is provided which penetrates a shielding lid for closing an upper opening and which is connected to an air conditioner whose tip is a vent in the new fuel storage. The new fuel storage according to claim 1. 5. The new fuel storage according to claim 1, wherein a cooling air-conditioning device having a fan and a heat exchanger is connected to a connection duct connected to the ventilation port in the new fuel storage to form a closed loop. 6. The fresh fuel storage, wherein a plurality of ventilation holes and connection ducts connected to the ventilation holes are provided,
6. The new fuel storage according to claim 1, wherein each of the new fuel storages is connected to an independent air conditioner or a cooling air conditioner. 7. The new fuel storage system has a system in which a connection duct connected to a vent is connected to an air conditioner, and a system connected to a closed loop cooling air conditioner including a fan and a heat exchanger. The new fuel storage according to claim 1, wherein: 8. The new fuel storage according to claim 1, wherein a refrigerant passage is provided in a lining of a wall surrounding the periphery and the bottom in the new fuel storage to flow a refrigerant. 9. In the new fuel storage, an internal thermometer and a temperature controller are provided, and a valve is inserted into a connection duct connected to an air conditioner, and the valve of the connection duct is determined based on the measured temperature in the new fuel storage. The new fuel storage according to claim 1, wherein the internal temperature is controlled by an operation. 10. The new fuel storage, wherein an internal thermometer and a temperature controller are provided to operate a fan in a closed-loop cooling air conditioner including a fan and a heat exchanger based on the measured temperature in the new fuel storage. 6. The new fuel storage according to claim 1, wherein the internal temperature is controlled by controlling the internal fuel temperature. 11. The radioactive waste treatment system according to claim 11, further comprising an internal radiation monitor and a selection controller, a valve inserted into an exhaust-side connection duct connected to a vent, and a branch from an upstream side of the valve. 4. The new fuel storage according to claim 1, further comprising a connection duct provided with a valve connected to the pipe, and selecting the processing system based on the measured radiation amount in the new fuel storage. 12. In the new fuel storage, an internal radiation monitor and a selection controller are provided, and a plurality of systems of an air conditioner connected to a connection duct inserted through a valve and an air conditioning mechanism of a closed loop cooling air conditioner are provided. 6. The new fuel storage according to claim 1, wherein a different air conditioning mechanism system is selected according to the measured radiation dose in the new fuel storage. 13. The new fuel according to claim 1, wherein in the new fuel storage, a shielding heat-dissipating hole for dissipating internal heat and shielding radiation is provided in a shielding lid for closing an upper opening. Storage.