JPH09152498A - Mobile local air discharge apparatus for catching of radioactive iodine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a time before a regular inspection is started, by constituting an apparatus of three units of a size whereby the units can be freely coupled/separated, freely rotate and accommodated in an elevator of a building. SOLUTION: A leak from a packing face is prevented by coupling of units 1, 2 and 3 by means of a large catch clip. Each unit 1, 2, 3 is turned to a negative pressure thereinside when the blower unit 3 operates, so that radioactive iodine or the like does not leak outside. The weathering unit 1 and a condenser is coupled via an air suction port 14. When a heater 13 and a motor 37 are started, the air in the condenser after a nuclear reactor is stopped is ventilated, and the radioactive iodine gas in the condenser can be removed with an efficiency of 99% or higher at all times. A regular inspection of the nuclear reactor can be started two days earlier after the operation is stopped because of the forced ventilation of the radioactive iodine gas included in the air in the condenser.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile local exhaust system for collecting radioactive iodine.

[0002]

2. Description of the Related Art In a nuclear power plant or the like, it is obliged to stop the nuclear reactor after a certain period and carry out a periodic inspection. Immediately after shutting down the reactor, the air in the closed system, mainly in the condenser, contains a small amount of radioactive iodine gas generated by nuclear fission, and in that state, the system was opened for periodic inspection. If the main equipment such as the turbine is opened, radioactive iodine gas may diffuse to the work place. For this reason,
Conventionally, with the passage of time, the periodical inspection is started after the radioactive iodine gas is reduced to a safe level.

[0003]

The problem with this prior art is that it takes time from the shutdown of the nuclear reactor to the start of the periodic inspection.

At a nuclear power plant or the like, when a large amount of radioactive iodine gas is generated in the system due to a fuel damage accident, etc.,
In order to ventilate and purify these, and to reduce their release to the environment, an emergency gas treatment device equipped with an impregnated activated carbon filter having excellent adsorption performance for radioactive iodine gas is installed. However, it cannot be used for the purpose of periodic inspection because it works only in an emergency such as a fuel damage accident. Also, in order to forcibly reduce the radioactive iodine gas contained in the air inside the condenser, it is necessary to suck the internal air from the manhole inside the condenser, but the manhole is on each floor. The fixed emergency gas treatment equipment cannot be used for the purpose of periodic inspection because it is scattered around.

[0005] The present invention has been made for the purpose of solving such problems of the prior art.

[0006]

Means for solving the above problems will be described below with reference to FIG. 1 corresponding to one embodiment.
explain. The present invention is composed of a weathering unit 1, a filter unit 2 and a blower unit 3, and the units 1, 2 and 3 are configured so that they can be coupled and separated from each other, and are rollable and in a building elevator. It is formed in a size that can be stored in.

In such a structure, the radioactive iodine gas contained in the air in the condenser can be forcibly reduced while moving through each floor.

[0008]

FIG. 1 is a diagram showing an embodiment of the present invention. In FIG. 1, 1 is a weathering unit, 2 is a filter unit, and 3 is a blower unit.

The weathering unit 1 comprises a unit body 11, a demister filter 12 and a heater 13. The unit body 11 is 800L x 8
It is a box body of 80W × 1000H. The back surface is opened, and a packing surface 5 is formed on the back surface outer frame 4 having a step (see FIG. 2). The hanging metal fitting 7 is fixed to the upper surface of the unit main body 11. On the front surface of the unit main body 11, a handle 8 is provided in the upper portion, an intake port 14 is provided in the center, and a drain box 15 is provided in the lower portion. A caster 9 with a stopper is provided on the bottom surface of the unit body 11 so as to project therefrom. A part of the large catch clip 10 is attached to the upper surface, both side surfaces and the bottom surface of the unit main body 11 near the rear outer frame 4 (see FIG. 2).

The demister filter 12 removes water droplets and foreign substances contained in the air in the condenser,
A unit of 610 × 610 × 100t is fixed to a partition plate 16 having a ventilation hole that is provided around the inside of the unit main body 11.

The heater 13 heats the intake air to reduce the relative humidity to 50% or less.
It is fixed to a partition plate 17 having a ventilation hole, which is provided around the inside of 1. The heater 13 prevents water vapor and impurities contained in the air passing through the activated carbon from adsorbing or reacting with the activated carbon, thereby deteriorating the ability of the activated carbon to collect radioactive iodine gas, that is, weathering. Insulation material duct 18 from the partition plate 17 to the back direction
Is protruding. A part of the heat insulating material duct 18 protrudes from the rear outer frame 4 toward the filter unit 2 side.

As shown in FIGS. 1 and 3, the filter unit 2 comprises a unit body 21, a prefilter 22, an activated carbon filter 23, and a HEPA filter 24. The unit body 21 is 1000L × 88
It is a 0 W x 1000 H box. The front surface and the rear surface are opened, and packing surfaces 5 are formed on the front outer frame 6 and the rear outer frame 4 having steps (see FIG. 2). The hanging metal fitting 7 is fixed to the upper surface of the unit main body 21.
Further, a free caster 9 with a stopper is provided on the bottom surface of the unit main body 21 in a protruding manner. A part of the large catch clip 10 is attached to the upper surface, both side surfaces and the bottom surface of the unit main body 21 near the front outer frame 6 and the rear outer frame 4 (see FIG. 2).

On the inner bottom surface of the unit main body 11, a roller mount 25 is partially projected to the blower unit 3 side.
Is erected. As shown in FIG. 4 (A), the roller mount 25 has a plurality of guide rollers 25B rotatably mounted between plates 25A which are erected opposite to each other, and FIG. As shown in FIG. 3, there is a bottom plate 25C in which a plurality of ball casters 25D are rotatably fixed.

The pre-filter 22 removes coarse particle dust contained in the air heated by the heater 13. The pre-filter 22 of 610 × 610 × 20t has a unit body 21.
It is detachably fixed to the front side of a partition plate 26 having a vent hole, which is circumferentially provided inside, through a mounting bracket 27.

The activated carbon filter 23 removes radioactive iodine gas contained in the air that has passed through the pre-filter 22, and is of the type (610 × 610 × 290t) × 2. A bed thickness of 2 inches is also used as the activated carbon filter 23.

The HEPA filter 24 removes the finely powdered activated carbon containing radioactive iodine that has been exfoliated and released from the activated carbon filter 23, and a HEPA filter of 610 × 610 × 150 t is used.

The activated carbon filter 23 and the HEPA filter 24 are placed on a roller mount 25 and detachably attached to a filter fixing frame 29 fixed to the back side of the partition plate 27 by a filter fixing means 28.

As shown in FIG. 5, the filter fixing means 28 has four ends which are fixed to the upper and lower sides of both sides of the filter fixing frame 29 so as to be swingable in the left and right directions, and a screw portion is provided at the other end. Hinge bar 28A, upper and lower flat bars 28B inserted into the hinge bar 28A, and hinge bar 28
And a thumbscrew 28C screwed to A.

The activated carbon filter 23 and the HEPA filter 24 are pushed into the unit body 21 from the back surface of the unit body 21 by using the guide roller 25B or the ball caster 25D, and then the flat bar 28 is used.
By inserting B into the hinge rod 28A and screwing the thumbscrew 28C, it is fixed to the unit main body 21. Since the activated carbon filter 23 and the HEPA filter 24 are pushed in or pulled out by using the guide roller 25B or the ball caster 25D, their replacement is easy.

As shown in FIGS. 1 and 3, the blower unit 3 includes a unit body 31, a partition wall 32, an intake port 33, a casing 34, a duct 35, an exhaust port 36, a motor 37,
It is composed of a motor mount 38. Unit body 3
1 is a box body of 1050Lx880Wx1000H. The front outer frame 6 has an opening on its front surface and a step is formed.
Has a packing surface 5. Unit body 31
The hanging metal fitting 7 is fixed to the upper surface of and the exhaust port 36 is provided. A handle 8 is provided on the back of the unit body 31. A caster 9 with a stopper is provided on the bottom surface of the unit main body 31 so as to project therefrom. A part of the large catch clip 10 is attached to the upper surface, both side surfaces and the bottom surface of the unit main body 31 near the front outer frame 6. The blower unit 3 has a rated air volume of 2000 m ³ /
H.

The weathering unit 1, the filter unit 2 and the blower unit 3 can be easily moved by using the casters 9 with stoppers, and the size of the weathering unit 1, the filter unit 2 and the blower unit 3 is the size of the building elevator, for example, frontage 1100 × depth 140.
It is set within 0 x height 2000mm, and it is easy to move to each floor using the building elevator.
Assembling each unit 1, 2, 3
This can be easily done by matching the packing surfaces 5 of the above and operating the large catch clip 10. In addition, each unit 1, 2,
The separation of 3 can be easily performed by operating the large catch clip 10.

Although the leakage of the packing surface 5 is prevented by connecting the units 1, 2, 3 with the large catch clip 10, the inside of each unit 1, 2, 3 is negative due to the operation of the blower unit 3. Since it becomes a pressure, radioactive iodine etc. will not leak outside.

When the inside of the condenser is connected to the weathering unit 1 through the intake port 14 and the heater 13 and the motor 37 are operated, the air inside the condenser after the reactor is stopped is ventilated and the inside of the condenser is cooled. The radioactive iodine gas contained in the air can always be removed with an efficiency of 99% or more. The compulsory reduction of the radioactive iodine gas contained in the air in the condenser will allow two days from the shutdown of the reactor to the start of periodic inspections.

The above is the case where the weathering unit 1, the filter unit 2 and the blower unit 3 are divided, but the weathering unit 1 and the filter unit 2 may be integrated depending on the size of the building elevator.

[0025]

As described above, the present invention provides:
It is composed of a weathering unit, a filter unit and a blower unit, and each unit is configured to be connectable and separable from each other, and rollable, and
It has a size that can be stored in the building elevator. Therefore, it is possible to forcibly reduce the radioactive iodine gas contained in the air in the condenser while moving each floor. Therefore, according to the present invention, it is possible to shorten the time from the shutdown of the nuclear reactor to the start of the periodic inspection.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

2A and 2B are diagrams showing a combined state of units constituting the present invention, in which FIG. 2A is a partial sectional view and FIG. 2B is a plan view.

FIG. 3 is a perspective view showing a filter unit and a blower unit constituting the present invention.

FIG. 4 is a perspective view showing a roller mount constituting the present invention.

FIG. 5 is a perspective view showing a filter fixing means that constitutes the present invention.

[Explanation of symbols]

 1 Weathering Unit 2 Filter Unit 3 Blower Unit 12 Demister Filter 13 Heater 22 Pre-filter 23 Activated Carbon Filter 24 HEPA Filter 25 Roller Stand 28 Filter Fixing Means 34 Casing 35 Duct 37 Motor

Claims (6)

[Claims] 1. A weathering unit, a filter unit, and a blower unit, each unit being configured to be connectable and separable from each other, rollable, and sized to be housed in a building elevator. Formed mobile local exhaust device for collecting radioactive iodine 2. A weathering filter unit and a blower unit, each unit being configured to be connectable and separable from each other and to be rollable.
In addition, a mobile local exhaust device for capturing radioactive iodine, which is formed in a size that can be stored in the building elevator 3. The mobile local exhaust system for capturing radioactive iodine according to claim 1, wherein the filter unit comprises a pre-filter, an activated carbon filter and a HEPA filter, and the activated carbon filter and the HEPA filter are movably mounted inside. 4. The weathering filter unit comprises:
Consists of a demister filter, heater, pre-filter, activated carbon filter and HEPA filter,
The mobile local exhaust system for capturing radioactive iodine according to claim 2, wherein an activated carbon filter and a HEPA filter are mounted movably inside. 5. A roller mount, a part of which projects toward the blower unit, is erected inside the filter unit, and an activated carbon filter and a HEPA filter are placed on the roller mount. No. 3 Mobile local exhaust system for collecting radioactive iodine 6. The weathering filter unit is internally provided with a roller mount partially protruding toward the blower unit, and an activated carbon filter and a HEPA filter are placed on the roller mount. A mobile local exhaust system for collecting radioactive iodine according to claim 4.