JPH07113677B2 - Liquid scintillator recovery and cleaning method and device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for collecting and washing radioactive waste generated after measurement in liquid scintillation measurement, which is widely used for measuring beta-ray emitting nuclides. More specifically, the present invention relates to a method and apparatus for recovering and washing a low-radioactivity liquid scintillator which is used as a medical waste or an experiment for biochemistry in radioactive waste.

[0002]

2. Description of the Related Art A radioactive waste treatment technology, particularly a recovery technology, has been remarkably developed in recent years. Above all, the field of nuclear power generation is well developed. In this way, although development is progressing in terms of industrial high-concentration radioactive waste treatment technology, in other fields, such as the medical science field, low concentrations and low toxicity are involved. Unexpectedly, the technology of waste treatment is delayed.

It can also be said that this is because the absolute amount of radioactive waste was relatively small and did not pose a problem so much, and thus the regulation was looser unlike the above-mentioned power generation. With respect to medical technology, particularly in recent years, diagnostic and therapeutic techniques utilizing radioactive substances have been greatly developed, and as a result, the amount of radioactive substances to be disposed of has dramatically increased. For example, there is a radioactive substance that is injected into a blood vessel and used to detect a malignant tumor or the like by observing the infiltration state of the tissue.

A liquid scintillation measuring technique is used to detect the presence or absence of this radioactive substance, but in this measurement, a liquid scintillator is put in a container and used. Of course, the liquid scintillator must be disposed of after use. The small container with a lid that holds the liquid scintillator cannot be discarded as it is due to legal regulations. Therefore, the liquid scintillator, which is now a waste liquid, is collected from the container, the container is washed, and the former is disposed of as waste, and the latter is reused or disposed of as waste.

However, until now, these processes have been performed manually. In other words, humans had to throw away the waste liquid from each container one by one and then wash each container by hand. Therefore, it sucked the scintillator evaporated during the work and was very harmful to the labor environment. Furthermore, the ability to clean is also extremely low, and in particular, uneven cleaning and mistakes in damage were unavoidable.

On the other hand, it is known that a container such as a bottle, which is not a radioactive waste liquid, is mounted on a conveyor chain and the inside of the container is washed with jet water (Japanese Patent Laid-Open No. 55-5598).
No. 7, Japanese Patent Laid-Open No. 56-95890, and Japanese Utility Model Laid-Open No. 3-
90684 publication). However, these containers are not liquid-filled and have no lid. Therefore, the lid is not removed from the container to collect the liquid containing the radioactive waste, and the liquid inside is not collected. The conventional one is just a cleaning device for the inside of a container or the like.

[0007]

The present invention is intended to solve the above problems and achieves the following objects.

An object of the present invention is to provide a liquid scintillator recovery apparatus and method for automatically recovering a liquid scintillator packed in a container which can be conventionally only manually done.

Another object of the present invention is to provide a liquid scintillator recovery method and apparatus capable of treating a large amount of liquid scintillator packed in a container.

Still another object of the present invention is to provide a method and an apparatus for collecting and cleaning a liquid scintillator packed in a container, which has a good environment for labor hygiene and has an extremely high cleaning ability.

[0011]

[Means for Solving the Problems] To solve the above problems, the following means are adopted.

[0012] A cassette holding a plurality of containers is intermittently moved by an endless belt, the lids of the containers are sequentially removed, and then the lids are dropped onto a lid receiving member for cleaning, and the containers are placed substantially downward. In this state, the waste liquid in the container is allowed to flow through a drain receiver to be collected, and thereafter, the process of injecting a cleaning liquid into the container and cleaning the container in a state in which the container is in a downward direction is performed in plural steps. This is a liquid scintillator recovery and cleaning method.

When cleaning in a plurality of steps, the cleaning liquid may be changed for each of the steps.

Means for realizing the above method include an endless belt which is driven and rotated intermittently, a plurality of cassette mounting members arranged in parallel on the endless belt, and a plurality of containers which are mounted on the cassette mounting member and hold a plurality of containers. For holding the container, a lid removing device arranged behind the endless belt for removing the lid of the container, and a lid cleaning device arranged under the lid removing device for receiving and cleaning the falling lid. And a drain recovery device that is disposed below the lid removal device and that recovers the waste liquid that drops from the inside of the container, and a cleaning device that is located below the endless belt and that cleans the inside of the container. Liquid scintillator recovery and cleaning device.

Further, it is preferable that the drain recovery device comprises a drain receiver and a drain receiver tank for recovering the waste liquid.

Further, the cleaning device preferably comprises the same number of cleaning nozzles as the number of the containers for cleaning the inside of the container, a cleaning liquid receiver for receiving the cleaning liquid which has been cleaned, and a cleaning liquid tank for collecting the cleaning liquid. .

Further, it is preferable that the lid cleaning device comprises a lid receiving member and a lid cleaning tank for agitating and cleaning the lid collected from the lid receiving member.

Further, it is preferable that the lid removing device includes a friction roller for pressing the lid and removing the lid by a frictional force.

[0019]

Focusing on the movement of the containers, first, the container holding cassette holding a plurality of containers is mounted on the cassette mounting member. When the endless belt is intermittently rotated forward, the container holding cassette mounted on the cassette mounting member moves forward. The lid of the container held in the cassette at the front position of the endless belt is removed by the lid removing device. At this time, the removed lid falls into the lid receiving member. After falling, the lid further drops to the net container and is stirred and washed in the lid washing tank.

Next, due to the movement of the endless belt, the drain drops to the drain receiver in a state where the container is oriented substantially downward, and is soon collected in the drain receiver tank. Eventually, the container completely faces downward, but in the state where the container is completely downward, a cleaning liquid is sprayed from the cleaning nozzle to the container to clean the inside of the container. The same washing process is repeated twice or more. Preferably, the cleaning liquid may be changed for each process child.

When the container holding cassette returns to its original position, the container holding cassette is removed from the cassette mounting member.
Since the container holding cassettes are arranged side by side with an interval of the endless belt, the container holding cassette filled with the next container is mounted on the empty cassette mounting member. The liquid scintillator is continuously washed in the recovery container by repeating the above steps.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an overall schematic view of a liquid scintillator recovery / washing apparatus, FIGS. 2 (A), 2 (B) and 2 (C) are details of a container holding cassette, and FIG. 3 is a view showing a state in which the lid of the container held by is removed, FIG. 4 is a view seen from the direction of arrow IV in FIG. 3, and FIG.
5 is a view seen from the direction of arrow V in FIG. FIG. 1 is an overall schematic view of a liquid scintillator recovery and cleaning device, which will be described.

The endless belt 1 has a width and is composed of two chains and a member for connecting the chains. 2 at both ends of the endless belt 1.
It is supported by four sprockets 2 that mesh with the book chain. The four sprockets 2 are supported by two shafts 3, and the two shafts 3 are rotatably supported by a machine body 30 (FIGS. 4 and 5) via bearings.

On the other hand, a sprocket 4 is fixed to the shaft 3. The sprocket 4 is rotationally driven intermittently by a sprocket fixed to the output shaft of an endless belt drive motor 6 via a chain 5. A plurality of container holding cassettes 20 are held on the endless belt 1. The container holding cassette 20 is for holding a plurality of containers V at the same time. The endless belt 1 is provided with a cassette mounting member 7 (see FIG. 3) for fixing the container holding cassette 10.

The upper part of the endless belt 1 can be moved forward (to the left in FIG. 1) by the rotation of the endless belt drive motor 6. On the endless belt 1, a plurality of container holding cassettes 20 described later are arranged in parallel at regular intervals.
The container holding cassette 20 is intermittently rotated by the endless endless belt 1. Focusing on the movement of the container V, the container V moves forward in a state of facing upward, and begins to change its direction downward at the upper end end (left end in the figure) of the endless belt 1, and gradually. The angle increases until it turns downward. Then, while facing downward, rearward (Fig. 1
Back to the right end) and move, and this time, at the last end of the endless belt 1 (upper right of FIG. 1), it starts to change its direction upwards,
The angle gradually increases, and finally it turns upward and returns to its original position.

A lid removing device 8 for removing the lid C of the container V is arranged near one sprocket 2 of the endless belt 1. The details of the lid removing device 8 for the containers V will be described later, but the lids C of the plurality of containers V that are linearly aligned and held in the container holding cassette 20 are arranged from one end to the other end (and vice versa). ) Is to remove one by one. A lid cleaning device 9 is disposed below the lid removing device 8, and the lid receiving member 91 steadily receives the lids C that are removed one by one and are falling.
The lid receiving member 91 is formed in a mesh shape so as to allow only liquid to pass therethrough. However, a lid cleaning tank 93 described later
You may arrange | position this inside and make it drop with a waste liquid together, and let only the cover C permeate | transmit and it may be caught by a net.

The lid C once dropped on the lid receiving member 91
Is further dropped and collected in the net container 92 in the lid cleaning tank 93. The lid cleaning tank 93 contains a washing liquid for washing the lid C, and the water level thereof is always kept at a constant level by the level switch 96. When the level exceeds a certain level, the overflow drain pipe 97 is used to receive the total waste liquid 87
Is discharged to. The waste liquid receiver 87 is appropriately discharged through the pump 86.

The lid cleaning tank 93 is also provided with a lid stirring blade 94. The lid stirring blade 94 is rotated by a stirring motor 95, and the washing efficiency is increased while hitting an excess current on the lid C in the net container 92. ing. The cleaning liquid for cleaning the lid C is supplied from the water supply pipe 82 through the water supply solenoid valve 83, and the drainage is drained through the drainage solenoid valve 98.

Similarly, a drain receiver 51 is arranged below the lid removing device 8 to receive the waste liquid falling from the container V. It is collected in the drain receiving tank 52 accumulated in the drain receiving 51. The drain receiving tank 52 is provided with a level switch 53 to keep the water level constant. Needless to say, when the waste liquid reaches a certain level or higher in the drain receiving tank 52, the electromagnetic valve 54 for drainage is opened and discharged, and the treatment specified by law is performed.

Below the endless belt 1, two cleaning devices, a first cleaning device 12 located on the front side (left side in the figure) and a second cleaning device 13 located on the rear side (right side in the figure), are connected in series. It is arranged. Two or more of these cleaning devices may be arranged, and in this case, the cleaning degree becomes higher. The first and second cleaning devices 12 and 13 have substantially the same structure, and have a cleaning nozzle 72 for cleaning the inside of the container V, a cleaning liquid receiver 71 for receiving the cleaning liquid after cleaning, and a cleaning liquid receiver 71. Collect cleaning liquid Cleaning liquid tank 7
4 and up.

The cleaning nozzle 72 holds the cleaning liquid in the container holding cassette 20 and is in a downward direction.
For cleaning the inside of the container V cleanly, and the cleaning liquid in the cleaning liquid tank 74 is pumped up by the cleaning pump 76 and used. It is also possible to supply the cleaning liquid from another route.

The number of the cleaning nozzles 72 is equal to the number of the containers V held in the container holding cassette 20, and the containers V of the entire cassette can be cleaned in a batch manner at once. The endless belt 1 is stopped during this cleaning. The cleaning liquid receiver 71 is for receiving the cleaned liquid after cleaning the inside of the container V by the cleaning nozzle 72, and the cleaning liquid accumulated therein is collected in the cleaning liquid tank 74.

The cleaning liquid tank 74 is provided with a ball tap 73 and keeps the water level at a constant position. When draining, drain the waste liquid through the solenoid valve 77.
Drain to 7. Each cleaning liquid tank 7 in the first cleaning device 12 located in the front and the second cleaning device 13 located in the rear
The cleaning liquid is supplied to the nozzles 4 through the water supply solenoid valve 85 and the same water supply pipe 84.

The cleaning liquid of the first cleaning device 12 and the cleaning liquid of the second cleaning device 13 may be the same or different, and may be the same or different when three or more cleaning devices are used. Incidentally, the first and second cleaning devices 12, 13 of this embodiment
Is composed of two units, but in principle it may be one unit,
It only slightly deteriorates the degree of cleaning.

Container Holding Power Cassette 20 FIGS. 2 (A), (B), and (C) show the container holding cassette 20, FIG. 2 (A) is a plan view, FIG. 2 (B) is a bottom view, and FIG.
(C) is a side view. The container holding cassette 20 is formed in an elongated shape with an H-shaped cross section than two side plates 15 having an H-shaped cross section and facing each other and a bottom plate 16 connecting them. An elastic material 17 (for example, silicon rubber) is attached to each side plate so that the side surface of the container V can be elastically gripped from both sides. Elastic material 1
The curved portions 19 are formed in the number 7 corresponding to the number of containers to be held, so that the side surface of the container V can be easily gripped. Of course, the curved portion 19 may be provided on the side plate 15 itself.

A spring body 18 is provided on the leg portion 21 below the side plate 15 to give an elastic effect to the leg portions 21. Further, the rails 41 of the cassette mounting member 7 are provided on the leg portions 21.
Mounting portion or bent portion 2 so as to fit into the recess 42 of
2 is formed. Therefore, when the bent portion 22 is laterally fitted into the rail 41 of the cassette mounting member 7 and is pushed in and slid, the container holding cassette 20 is reliably mounted and set on the cassette mounting member 7.

In order to hold the container V in the container holding cassette 20, the elastic member is simply formed by digging into the spring body 18 and expanding the side plates 15 and 15 and pushing the container V in order from above the cassette 20. It can be easily set due to the repression effect of 17.

Lid Removing Device 8 FIG. 3 is an enlarged view of the container holding cassette 20 and the lid removing device 8 . FIG. 4 shows the lid removing device 8 as seen from the direction of arrow IV in FIG.
5 is a top view of FIG. 5, and FIG. 5 is a view of the container lid removing device 8 as seen from the direction of arrow V in FIG. U-shaped frame member 36
Two lid removal motors 32 are arranged side by side in
Friction rollers 34 (made of silicone rubber rollers) are provided to the output shafts 40 and 40, respectively, via reduction gears 33 on the lid removing motor 32. When the friction roller 34 rotates, the lid C is rotated by the frictional force and released from the container V. The number of the friction rollers 34 is not limited to two, but may be one as long as it has a pressure bonding force.

The pressing roller 3 is attached to the tip of the frame member 36.
5, the side plate 15 of the container holding cassette 20 is provided.
It is pinched from the side and pressed. That is, the friction roller 34
When the lid C is rotated between them, the container V is hung and pressed so as not to rotate and rotate. of course,
The pressing roller 35 has the same effect even when pressing the side plate 15 of the container V, and such a structure may be adopted.

Ball nut 39 fixed to the frame member 36
Is engaged with a feed screw 31, and the feed screw 31 is attached to the machine base 30 (see FIGS. 4 and 5) along the length direction of the container holding cassette 20. The feed screw 31 is used to remove the lid drive motor 3 attached to the machine base 30.
7 (FIG. 4) is rotated through the sprocket, chain, and sprocket. Since the nut 39 is moved by the rotation of the lid removing drive motor 37, the entire frame member 36 moves along the axial direction of the feed screw 31. That is, the lid removing device 8 moves along the length direction of the container holding cassette 20. During this movement, the lid removing motors 32, 32 are driven to remove the screwed lid C from the container V.

The guide bar 38 (FIGS. 3 and 4) is provided on the machine base in parallel with the feed screw 31, and guides the lid removing device 8 accurately along the feed screw 31. Therefore, the friction roller 34 is rotated by the drive of the lid removing motor 32, and when the lid C of a certain container V is removed, the lid removing movement motor 3
By driving 7, the entire frame member 36 moves to the next container V position. Then, the lid C of the container V is removed. In this way, the containers V held in the container holding cassette 20 one after another
Remove the lids C of one after another.

[0042]

As described above, the liquid scintillator can be collected automatically and in a large amount, which could only be done manually in the past. In addition, the environment for labor hygiene is good, and the ability to clean containers is extremely high.

[Brief description of drawings]

FIG. 1 is an overall schematic view of a liquid scintillator recovery and cleaning device.

FIG. 2A is a plan view of a container holding cassette. FIG. 2B is a bottom view of the container holding cassette.
FIG. 2C is a side view of the container holding cassette.

FIG. 3 is an enlarged view of a lid removing device.

FIG. 4 is a top view of the lid removing device as viewed from the direction of arrow IV in FIG. .

FIG. 5 is a side view of the lid removing device as seen from the direction of arrow V in the figure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Endless belt, 6 ... Endless belt drive motor, 7 ... Cassette mounting member, 8 ... Lid removing device, 9 ... Lid cleaning device,
20 ... Container holding cassette, 11 ... Drain recovery device, 12
... first cleaning device, 13 ... second cleaning device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Misao Shoji 85-5 Ipponmatsu, Numazu City, Shizuoka Prefecture In the Shoji Misao Manufacturing Co., Ltd. (56) Reference JP-A-5-249292 (JP, A) JP-A-5-19097 (JP, A) Jikkouhei 4-15347 (JP, Y2)

Claims (7)

[Claims] 1. A cassette holding a plurality of containers is intermittently moved by an endless belt, the lids of the containers are sequentially removed, and then the lids are dropped onto a lid receiving member for cleaning, and the containers are Performing a plurality of steps of cleaning the container by injecting a cleaning liquid into the container in a state in which the waste liquid in the container is made to flow downward to a drain receiver to collect the liquid, and then the container is in a downward direction. Liquid scintillator recovery and cleaning method characterized by: 2. The liquid scintillator recovery and cleaning method according to claim 1, wherein the cleaning liquid is changed for each of the steps when cleaning is performed in a plurality of steps. 3. An endless belt which is driven and rotated intermittently, a plurality of cassette mounting members arranged in parallel on the endless belt, and a container holding cassette mounted on the cassette mounting member for holding a plurality of containers. A lid removing device disposed behind the endless belt for removing the lid of the container, a lid cleaning device disposed below the lid removing device for receiving and cleaning the falling lid, and the lid removing device. A liquid scintillator recovery and cleaning device including a drain recovery device that is disposed below the container for recovering the waste liquid that drops from the container, and a cleaning device that is located below the endless belt and that cleans the inside of the container. . 4. The liquid scintillator recovery / cleaning device according to claim 3, wherein the drain recovery device comprises a drain receiver and a drain receiver tank for recovering the waste liquid. 5. The cleaning device according to claim 3, wherein the cleaning device has the same number of cleaning nozzles as the number of the containers for cleaning the inside of the container, a cleaning liquid receiver for receiving the cleaning liquid that has been cleaned, and a cleaning liquid for recovering the cleaning liquid. Liquid scintillator recovery and cleaning device characterized by comprising a tank. 6. The liquid scintillator recovery system according to claim 3, wherein the lid cleaning device comprises a lid receiving member and a lid cleaning tank for agitating and cleaning the lid recovered from the lid receiving member. Cleaning device. 7. The liquid thin vial scintillator recovery and cleaning device according to claim 3, wherein the lid removing device includes a friction roller that is pressed against the lid and removes the lid by a frictional force.