JPH08309133A - Apparatus for recovering dust containing nuclear fuel substance - Google Patents

Abstract

PURPOSE: To provide an apparatus for recovering dust containing nuclear fuel substances which can collect the dust of nuclear fuel substances surely with good recovery efficiency, has simple structure, and is easy of exchange work for metal filters and filter cloths. CONSTITUTION: More than one cylindrical metal filter 2 is arranged in a dust collector main body 1 which is connected with piping 11 for sucking gas containing the dust of nuclear fuel substances. The filters 2 are held on an upper plate which closes a dust collector main body 1, and the upper ends are connected with piping 10 for backwashing air in which the check valve of a glove box penetration part through a manifold 22 and a three-way change- over valve 6 and a piping 24 connected to an exhaust blower 9. The outside of the filter 2 is surrounded by a filter cloth 3 the mesh of which is smaller than that of the metal filter 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nuclear fuel material-containing dust recovery apparatus for collecting and recovering dust of nuclear fuel material, and in particular, collecting the dust of nuclear fuel material in a glove box in a nuclear fuel pellet manufacturing process, The present invention relates to a nuclear fuel material-containing dust recovery device having a structure suitable for recovery.

[0002]

2. Description of the Related Art Conventionally, as a dust recovery apparatus, a cyclone (generally, a cyclone is a gas flow containing solid fine particles descends while rotating along an inner wall of a cylinder, during which a centrifugal force acts on the dust. The dust is a structure that moves in the wall direction and is separated from the air flow.) And a dust filter using a bag filter were the mainstream, but the structure of this cyclone dust collector is extremely high. Although it was simple, the dust collection efficiency was low. Further, although the dust collector using the bag filter has a high dust collecting efficiency, it has a complicated structure and is large in size and high in cost. In particular, when the dust collector using the bag filter is installed in the glove box in the nuclear fuel pellet manufacturing process, the structure is complicated, it is difficult to replace the filter, and the life of the filter is short.

A dust collector as shown in FIG. 3 has been developed. In this dust collector, a plurality of cylindrical metal filters 32 are arranged in a cyclone dust collector body 31, and each cylindrical metal filter 32 is attached to an upper plate 33 that closes the upper end of the dust collector body 31. In addition, an inner cylinder 34 that surrounds the plurality of metal filters 32 is provided, and the upper end of the inner cylinder 34 is attached to the upper plate 33.
It is attached to. Since the bag filter has a problem of early deterioration due to radiation, a metal filter is used.

Further, a pipe 36 for collecting dust-containing gas is connected to the upper part of the side wall of the dust collector body 31, and a dust collection box 37 is provided at the lower part of the dust collector body. The pipe 38 for passing backwash air for backwashing the metal filter has a backwash nozzle 39 at its tip, and the backwash nozzle is arranged in the upper casing 35 at a space above the metal filter. Further, the pipe 40 for sucking gas in the dust collector body communicating with the exhaust blower communicates with the inside of the upper casing 35, and exhausts from the upper casing collectively. The main body of the dust collector collects dust by a cyclone and also collects dust by adhering to the metal filter, and further cleans the metal filter by backwash air and at the same time exhausts it through the inside of the upper casing.

[0005]

However, this type of dust collector is connected to the exhaust pipe 40 even when backwashing is performed, and part of the air from the backwash nozzle 39 is exhausted as it is. Therefore, there is a problem that the cleaning efficiency is reduced, the metal filter is clogged quickly, and the dust collection efficiency is low, and the replacement operation of the clogged metal filter is also difficult. It had a problem that it could not be done unless it was disassembled and decomposed.

Therefore, the present invention has been made in view of the above problems, and can reliably collect dust, has a high recovery efficiency, and has a simple structure, and the replacement operation of the metal filter and the filter cloth is extremely easy. It is an object of the present invention to provide a nuclear fuel material-containing dust recovery device that can be used.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the present invention takes the following technical means. That is, in the nuclear fuel substance-containing dust recovery apparatus of the present invention, a plurality of cylindrical metal filters 2 are arranged in the cyclone dust collector body 1 connected to the pipe 11 for sucking the gas containing the nuclear fuel substance dust. These cylindrical metal filters 2 are mounted and held on an upper plate 20 that closes the dust collector main body 1, and the upper ends of the metal filters 2 penetrate the glove box through the individual connecting pipes 22 and the three-way switching valve 6, respectively. Is connected to the backwashing air pipe 10 in which a check valve 25 is installed and the pipe 24 leading to the exhaust blower 9, and the outside of each metal filter 2 is a filter cloth having a mesh smaller than the mesh of the metal filter. The structure is individually encircled by 3.

Further, in the present invention, a pipe 11 for sucking the gas containing dust of the nuclear fuel material is connected to a vertical cylindrical header 12 having a plurality of dust collecting nozzles 13.
Another feature is a structure in which a dust collection box 14 is detachably provided below the header 12.

At least one vertical cylindrical rising pipe 15 for collecting dust is provided in the middle of a pipe 11 for sucking gas containing nuclear fuel dust, which connects the header 12 and the dust collector body 1.
Is preferably arranged and carried out.

[0010]

In the nuclear fuel substance-containing dust recovery apparatus configured as described above, the double structure of the metal filter 2 and the filter cloth 3 enables sufficient dust collection and the connection pipe 22 for ejecting backwash air. Since the tip is directly connected to the upper end of the metal filter 2, the backwashing efficiency is good, the service life of the metal filter and the filter cloth can be extended and the replacement frequency can be reduced, and moreover, the metal filter and the filter cloth are used. The double collection greatly improves the dust collection efficiency.
Also, the structure is simplified and the filter cloth can be easily replaced.

[0011]

An embodiment of the present invention will be described below with reference to the drawings. 1 and 2, reference numeral 1 denotes a dust collector main body of the nuclear fuel substance-containing dust recovery apparatus A.
Is formed in a cylindrical shape with a narrow mouth at the bottom, and a dust recovery box 5 is detachably provided at the lower end thereof. Further, an inner cylinder 4 having a lower end opening is vertically provided inside the dust collector body 1 with a proper space therebetween. The dust collector body 1
An upper plate 20 that closes the upper part of the dust collector main body is detachably attached to a flange portion 19 at the upper end of the via a bolt 23. Inside the inner cylinder 4 of the dust collector body 1, three cylindrical metal filters 2 are arranged in three rows. A filter cloth 3 is attached to surround each of the cylindrical metal filters. The filter cloth 3 is an acrylic resin filter cloth having a mesh surrounding the metal filter and smaller than the mesh of the metal filter.

The upper plate 20 is formed with holes corresponding to the number of the metal filters 2, and the metal filters 2 and the filter cloth 3 are attached to the respective holes through the joints 21. The lower end of the connecting pipe 22 is connected to the joint 21 and is directly communicated with the cylindrical shape of the metal filter 2. The other end of the connecting pipe 22 is connected to the three-way switching valve 6. One of the other ends of the three-way switching valve 6 is connected to the backwashing air pipe 10 in which the check valve 25 in the glove box penetration portion is installed, and the other is connected to the pipe 24 of the exhaust blower 9, The backwashing air pipe 10 and the exhaust blower pipe 24, each of which is provided with a check valve 25 through the glove box, can be alternately switched.

The joints 21, the connecting pipes 22 and the three-way switching valves 6 are individually arranged in quantities in the respective metal filters 2. Reference numeral 7 is a hepafilter that finally collects residual dust from the gas collected by the dust collector body 1, and 8 is a flow meter.

A pipe 11 for sucking gas containing nuclear fuel dust is connected to the upper part of the dust collector body 1.
The inlet of the pipe 11 to the dust collector body is oriented tangentially to the axis of the dust collector body.

Further, the pipe 11 for sucking the dust-containing gas of the nuclear fuel material is connected to a vertical cylindrical header 12. This header 12 has many dust collecting nozzles 1
3 is provided so that dust in the atmosphere can be taken into the header from the dust collecting nozzle. The inlet of the header of the dust collecting nozzle 13 is oriented in a tangential direction perpendicular to the axis of the header, and the header 12 itself also has a cyclone function. The lower part is formed so that the fallen dust can be collected by a collection box 14 which is detachably attached, so that the dust before entering the dust collector body 1 can be collected and collected in advance. is there.

Further, at least one vertical cylindrical rising pipe 15 for collecting dust is provided in the middle of the pipe 11 for sucking the gas containing nuclear fuel dust which connects the header 12 and the dust collector body 1. . The rising pipe 15 is also a cyclone like the header 12, and a dust collection box 16 is detachably provided at the lower part thereof to further collect and collect dust before entering the dust collector body. .

Experimental Example 1 Next, Experimental Example 1 shows the dust recovery rates of the metal filter surrounded by the filter cloth of the present invention and the conventional metal filter alone. The metal filter 2 has a diameter of 45 mm and a length of 40
The filter was a 0 mm bottomed cylindrical one formed of metal having a mesh of 5 μm, and the filter cloth used was an acrylic cloth having a mesh of 1 μm.

The small diameter nozzle 1 of the dust collecting hose 18 shown in FIG.
The amount of suction when a simulated powder (using fine tungsten powder) of the same density as the nuclear fuel powder is sucked from 7 and backwashing is not performed during suction, and suction is continued until the flow meter 8 falls to 80% of the initial value. When the amount of dust collected in the dust collection box 5 or the flow rate reaches 80%, the exhaust blower 9 is not stopped, and the three-way switching valve 6 is switched to supply the backwash air from the pipe 10 through which the backwash air is passed. The filter cloth was blown to wash the filter cloth, and the amount of dust collected and the collection rate thereof were examined.

[0019]

[Table 1]

As a result of the above, the dust can be collected about 5 times more reliably than the conventional apparatus, and the amount of recovery by backwashing is about 8 times, clogging is slow, and the metal filter is frequently used as in the conventional apparatus. It was found that the dust collection efficiency was extremely good because there was no need to replace the.

Experimental Example 2 Next, in Experimental Example 2, before the dust is collected and collected by the dust collector body 1, the dust is collected by the header 12 and the rising pipe 15 in advance.
The case of collection is shown. A dust collecting nozzle 13 shown in FIG. 1 sucks a simulated powder (using fine tungsten powder) having the same density as the nuclear fuel powder to collect dust in the collecting boxes 14 and 16 and the collecting box 5, and the dust collecting nozzle 13.
As a result of investigating the amount of recovery from the path to the metal filter 2, Table 2 is obtained.

[0022]

[Table 2]

From the above results, it can be seen that if the dust is collected and collected by the header and / or the rising pipe before the dust is collected by the dust collector body 1, the residual amount from the dust collector body can be small. It was

[0024]

As described in detail above, according to the nuclear fuel substance-containing dust recovery apparatus of the present invention, the dust of the nuclear fuel substance can be reliably recovered, and the clogging of the dust collector body is slow,
The recovery efficiency is good together with the recovery rate. Moreover, since the structure is simple and there is no upper casing on the top plate as in the conventional case, the replacement operation of the metal filter and the filter cloth is easy. In particular, the exhaust is closed during backwashing by switching between backwashing and exhaust by the three-way switching valve, and the tip of the connecting pipe that ejects backwash air is directly connected to the upper end of the metal filter. The washing efficiency is improved, the service life of the metal filter and the filter cloth is extended, the replacement frequency is reduced, and the dust recovery efficiency can be maintained at a high level.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a nuclear fuel material-containing dust recovery device of the present invention.

FIG. 2 is a vertical sectional view of a dust collector body of the nuclear fuel material-containing dust recovery apparatus of the present invention.

FIG. 3 is a vertical cross section of a conventional dust collector body.

[Explanation of symbols]

 A ... Dust recovery device containing nuclear fuel material 1 ... Dust collector body 2 ... Metal filter 3 ... Filter cloth 4 ... Inner cylinder 5 ... Dust recovery box 6 ... Three-way switching valve 7 ... Hepa filter 8 ... Flowmeter 9 ... Exhaust blower 10 ... Pipe for backwashing air 11 ... Pipe for sucking gas containing nuclear fuel dust 12 ... Header 13 ... Dust collection nozzle 14 ... Dust collection box 15 ... Rise pipe 16 ... Dust collection box 20 ... Top plate 24 ... Exhaust blower Piping of 25 ... Check valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Kitaguchi 2-1, 2 Kisejijima, Amagasaki City, Hyogo Prefecture Kimura Kakoki Co., Ltd. Kimura Kakoki Co., Ltd.

Claims (3)

[Claims] 1. A plurality of cylindrical metal filters (2) are arranged in a dust collector body (1) connected to a pipe (11) for sucking a gas containing dust of a nuclear fuel material, and these cylindrical metal members are arranged. The filter (2) is mounted and held on the upper plate (20) that closes the dust collector body (1), and the upper end of each metal filter (2) is connected to a separate connecting pipe (22) and three-way switching valve (6). Through the glove box through the check valve (25) is installed in the backwashing air pipe (10) and the exhaust blower (9) to the pipe (24) is connected to each of the metal filters (24). A nuclear fuel material-containing dust recovery device characterized in that the outside of (2) is individually surrounded by a filter cloth (3) having a mesh smaller than that of the metal filter. 2. A pipe for sucking a gas containing nuclear fuel dust in the nuclear fuel material-containing dust recovery apparatus according to claim 1.
(11) is connected to a vertical cylindrical header (12) having a plurality of dust collection nozzles (13), and a dust collection box (14) is detachably provided under the header (12). A nuclear fuel material-containing dust recovery device. 3. The nuclear fuel material-containing dust collecting apparatus according to claim 2, wherein a pipe (11) connecting the header (12) and the dust collector body (1) for sucking gas containing nuclear fuel dust has a vertical cylindrical shape. 1. A dust recovery apparatus for nuclear fuel material, characterized in that a rising pipe (15) for collecting dust is arranged, and a dust collecting box (16) is provided under the rising pipe (15).