JPH0239290B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dust collector for radioactive particles and other general dust.

In facilities that handle radioactive materials, there are many facilities that handle powder mixed with radioactive materials, and in order to prevent the powder from scattering to the outside, the inside of the equipment is generally controlled under negative pressure. In order to maintain negative pressure, a suction method using a blower or the like is used. When this negative pressure is controlled, powder containing radioactive substances is naturally entrained in the airflow. Furthermore, when thermal means such as melting or sintering are used to reduce the volume and solidify noncombustible powder such as incinerated ash containing radioactive materials, the incinerated ash itself or the gas and Many thermal decomposition products called fumes are generated, and it becomes necessary to remove these substances.

Generally, a high performance particle filter, a so-called HEPA filter, is used to remove these powders from the exhaust air stream under the above-mentioned negative pressure control. this
Although HEPA filters have high performance, they tend to become clogged with trapped powder and are mainly disposable. Therefore, as an economical method, it is advisable to install a filter with a large collection capacity in front of the HEPA filter. A bag filter is usually considered as a filter used in the preceding stage, but the bag filter generally has a small filtration area, and as a result, the bag filter itself becomes large. For this reason, there is a high risk of radioactive powder scattering to the outside during replacement, and replacement work is also not easy.

Furthermore, when collecting general dust-containing air, especially when the amount of dust is large, it is desirable to continuously discharge the collected dust separately from taking out the filter. Even in that case, it is preferable that the filter be replaced in a closed space.

This invention was made in order to solve these conventional problems, and it is possible to reliably prevent dust from scattering to the outside, facilitate filter replacement work, and continuously remove dust. The present invention provides a dust collector that can discharge dust.

That is, in the present invention, the inside of the cylindrical housing is divided into an upper chamber and a lower chamber by a partition plate, the upper chamber is formed with a purified gas exhaust port and a filter supply port, and the lower chamber is formed with a purified gas outlet and a filter supply port. The partition plate is provided with a plurality of filter holding parts on a circular locus, and the filter holding part inserts the filter from above into the upper chamber and lowers the filter into the upper chamber. A filter outlet is formed at the bottom of the lower chamber, and a filter outlet and a continuous dust exhaust means are connected to the outlet, and each filter is held in the upper chamber. A backwash nozzle is arranged to eject air to the filter held in the body, and this backwash nozzle is connected to the tip of an air supply pipe rotatably arranged around the center of the upper chamber. A scraper is provided at the bottom of the chamber and is rotatable around the center of the lower chamber for supplying the powder on the bottom plate of the lower chamber to a continuous dust discharge means.

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4, the housing of the device is composed of an upper chamber 1 and a lower chamber 2.
and are connected to each other with a partition plate 3 that divides their internal space interposed therebetween. The upper chamber 1 is formed with an outlet 4 and a filter supply port 5, and the lower chamber 2 is formed with an inlet 26 for gas to be treated and a filter outlet 17.
is formed. The filter supply port 5 is sealed with a vinyl bag 31 if radioactive material is present. This vinyl bag is not necessary in general cases, but it can be attached as necessary when treating toxic powder even in general cases.

A holding portion 13 for the filter 9 is formed on the partition plate 3, and a cylindrical guide plate 7 is arranged between this and the filter supply port 5. The guide plate 7 is formed of a perforated plate and has a notch so that the backwash nozzle 14 can pass therethrough. In the illustrated example, four guide plates 7 and holding parts 13 are arranged in the circumferential direction.
The nozzle 14 is rotatably supported by a bearing 16 provided on the upper plate 11 and is rotationally driven by a motor 70. The filter 9 is made of a nonwoven fabric made of organic fibers such as cotton, nylon, tetron, acrylic, and pyrene, and inorganic fibers of asbestos, glass, and metal, and is formed into a cylindrical pleat shape to increase the filtration area. Since the filter in use becomes clogged when filtering powder, the backwash nozzle 14 and the backwash nozzle 14 are used to eject pulse air for removing powder into the filter 9 at regular intervals. A bench lily 15 is arranged to efficiently introduce the blown air into the filter, thereby enabling backwashing.

A shaft 32 is rotatably attached to the lower part of the guide plate 7 by a rib 36, and an operating rod 3 is attached to this shaft 32.
3 and 34 are installed. The operating rod 34 is given a clockwise rotational force by a spring 35, and the operating piece 3 attached to the tip of the operating rod 34
6 passes through a hole formed in the holding part 13, and the tip thereof is a recess 9 formed in the flange 91 of the filter 9.
Lock at 3. This prevents the filter 9 from falling accidentally. Further, a packing 9 is provided between the outer peripheral surface of the flange 91 and the inner peripheral surface of the holding part 13.
4 is arranged to form a seal between the upper chamber 1 and the lower chamber 2.

A rotation guide 22 is disposed within the lower chamber 2, and is held by a central shaft 23 passing through the bottom plate 21 via an arm 24. The central shaft 23 is a motor 29
A rotational force is transmitted from the rotary guide 22 to move the rotary guide 22 below the filter 9 at an arbitrary position, thereby transporting the filter 9 supplied therein to the filter outlet 17. Also, the central axis 2
3 is provided with a radially extending scraper 28, which scrapes up the powder that has fallen onto the bottom plate 21 and sends it to the filter outlet 17.

A discharge chamber 80 communicates with the filter discharge port 17,
The discharge chamber 80 has a filter outlet 63 on its side.
is formed, and a dispensing chamber 8 is connected to the lower part. The discharge chamber 80 is provided with a floor 82 made of a perforated plate, and a pushing device 6 is provided on the side thereof, and the filter 9 that has fallen onto the floor 82 is pushed out to the filter outlet 63 by the rod 61 of the pushing device 6. That's what I do. Inside the dispensing chamber 8 is a screw 8 which is rotated by a motor 88.
1 is placed. A vinyl bag 69 is attached to the filter outlet 63 if necessary. 27 is an inspection port, and 60 is a buttful plate.

Next, the operation of the above device will be explained. When the gas to be treated is sent into the lower chamber 2 from the inlet 26, the gas passes through the filter 9, where dust such as radioactive material particles is removed, and the gas becomes clean and enters the upper chamber 1. It is sent and taken out from the discharge port 4. To replace the filter 9, lower the new filter from above, and use the filter to move the operating rod 3.
By pressing 3, the shaft 32 is rotated counterclockwise, and the actuating piece 36 is removed from the recess 93. moreover,
By pushing in the new filter, the filter 9 falls into the rotating guide 22. When the new filter is further lowered and positioned on the inner circumferential surface of the holding part 13, the operating rod 34 is pulled by the force of the spring 35, and the operating piece 36 is fitted into the recess 93, thereby being locked and held.

The filter 9 that has fallen into the rotating guide 22 is moved to the filter outlet 17 by the rotation of the central shaft 23.
It is carried upwards and falls onto the floor 82. Then, the filter 9 is pushed out by the rod 61 to the filter outlet 63 by the operation of the push-out device 6. The above operation is performed sequentially on the filters arranged at four locations in the circumferential direction. The dust brushed off by backwashing is continuously fed into the dispensing chamber 8 through the floor 82, where it is continuously dispelled by the screw 81.
Therefore, even if the amount of dust is very large, there will be no problem, and since most of the dust has been removed, the filter can be easily removed.

If the dust contains radioactive substances, the method shown in FIG. 5 may be used to prevent the dust from scattering to the outside. First, as shown in FIGS. 5A and 5B, the cover 18 is removed and the filter supply port 5 is covered with a vinyl bag 50. A filter 9a is placed in the vinyl bag 50 in advance, and using the glove 40 attached to the vinyl bag 50, remove the vinyl bag 31 sealing the filter supply port 5 as shown in C and D. Put the new filter 9a into the vinyl bag 50 and lower the new filter 9a as shown in E and F.
is dropped into the rotating guide 22, and a new filter 9a is set.

Next, as shown in
After the plastic bag 31 and the glove 40 are sealed and removed, the cover 18 is attached. Next, move the rotation guide 22 to the filter outlet 1.
7, push the filter 9 that has fallen onto the floor 82 into the filter outlet 63 with the rod 61 as shown in R, N, R, and place the filter 9 into the vinyl bag 69 that seals the filter outlet 63. After charging, the vinyl bag 69 is cut by melting. After the storage container 25 is transported to a predetermined location and the vinyl bag 69 containing the filter 9 is disposed of,
Place a new vinyl bag 69a over the filter outlet 63 and attach the lid 62. In addition, in this case, the remaining vinyl bag 69 that was fused
is removed inside the vinyl bag 69a,
This relationship is not shown.

In this way, the filter supply port 5 and the filter outlet 63 are sealed with the vinyl bag 18 and the vinyl bag 69 when the filter 9 is replaced.
The filter 9 and the lower chamber 2 are not in direct communication with each other, so that replacement can be carried out.
There is no risk of radioactive materials scattering when replacing the parts, and the replacement work can be done easily. In addition, when using it for general dust collection, there is no need to attach a vinyl bag.

As explained above, in this invention, a filter holding portion is provided on the partition plate that divides the inside of the housing into upper and lower parts, so that the filter can be replaced while the inside of the housing is sealed, and the dust can be taken out continuously. This prevents dust from scattering and allows the filter to be easily replaced.

In addition, in the upper chamber, a backwash nozzle that blows air to the filter held in the filter holder is arranged so that its position can be changed, making it possible to backwash a clogged filter. In addition, the filter can be loaded without the backwash nozzle getting in the way.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, and FIGS. 2 and 3 are the - line and - line in FIG. 1, respectively.
Line sectional view, Figure 4 is an enlarged view of Figure 1, Figure 5
Figures A to F are process explanatory diagrams of filter replacement. 1... Upper chamber, 2... Lower chamber, 3... Partition plate, 5... Filter supply port, 6... Extrusion device, 8... Dispensing chamber, 9
...filter, 63...filter outlet, 17...filter outlet, 82...floor.

Claims (1)

[Claims] 1 The inside of the cylindrical housing is divided into an upper chamber and a lower chamber by a partition plate, the upper chamber has an outlet for purifying gas and a filter supply port, and the lower chamber is for introducing gas to be purified. The partition plate is provided with a plurality of filter holding parts on a circular locus, and the filter holding parts are arranged so that the filter can be inserted from above the upper chamber and taken out to the lower chamber. A filter outlet is formed in the lower part of the lower chamber, and a filter outlet and a continuous dust exhaust means are connected to the outlet. A backwash nozzle that blows air to the filter is arranged, and this backwash nozzle is connected to the tip of an air supply pipe that is rotatably arranged around the center of the upper chamber. A dust collector characterized in that a scraper for supplying powder on a chamber bottom plate to a continuous dust discharge means is rotatably provided around a central portion of a lower chamber.