JPH01270700A - Compressed volume reduction of radioactive solid waste - Google Patents

Abstract

PURPOSE:To avoid damaging of an hole opening pipe during compression of a container containing a waste and to intend improvement of compression efficiency, by making the hole opening pipe retractable into a pushing ram when a force more than a certain limit value works on the hole opening pipe. CONSTITUTION:At one or both of a corresponding part to a bottom of a metal mold 3 on a base plate 2, and an end of a pushing ram, rotating plates 42 and 8 which are freely rotative around the axis of the two parts mentioned above, are fixed. Moreover, a hole opening pipe 7 is provided at the center of the pushing ram 4 end so as to be movable in and out to the pushing ram 4. Movement of the pipe 7 is adjusted to protrude from the pushing ram 4 so as to be able to have enough strength for punching a hole to a container 1 during a beginning stage of compression but to be pushed back without resisting against a stress generated with progress of the compression work, and the hole opening pipe 7 is connected to an air filter 9 via an air vent pipe 43. With this procedure, damaging of the hole opening pipe can be avoided during compression of the container containing a waste and a compression efficiency can be intended to be improved.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an improvement in an apparatus for compressing and sterilizing a container containing radioactive waste. [Prior art] Among the low-level radioactive waste generated in 1M nuclear power plants and other facilities, non-flammable solids such as metal pipes, ends of combustible plastic plates, crows, concrete, etc. The crushed pieces of items 1 to 1 are stored in a container such as a drum can. When disposing of this, do not reduce the volume (
It is usually compressed in the -axial direction, or in the case of drums, in the vertical direction to reduce the volume. Various devices have been devised for this purpose. A recent example is JP-A No. 63-27800, which adopts a structure in which a cylindrical mold and a ram-type compression mold are combined with a lateral removal mechanism, and after the compression is completed, the kite frame and A device called a blade is disclosed in which an integrated mold is lifted to release the compressed body from the mold, and the compressed body is pushed out onto a conveyor by the above-mentioned removal mechanism. However, if compression is performed carelessly, the pressure of the air inside the sealed container will increase, potentially causing the container to burst. The rupture is accompanied by the scattering of the contents, resulting in contamination of the set point I and radiation exposure of workers. As a countermeasure for this, JAERI-M527/l (Showa 4
8) [Method-1 for compressing solid waste contaminated with low to medium-level Plu-1-Nium is carried out in a device essentially consisting of a cylindrical mold and a compression ram, and a hole is opened in the cylinder head for compression. It is recommended to use a tube with a hole in the top plate of the container during compression. However, in the process of putting this type of compression volume reduction device into practical use, we experienced that the perforated tube could be damaged or the compression efficiency could drop, making it impossible to achieve the desired volume reduction. [Problems to be Solved by the Invention] The purpose of the present invention is to solve the above-mentioned problem, and to solve the problem of reducing the volume of radioactive solid waste by reducing the risk of damage to the open-hole pipe when compressing the container containing the waste. An object of the present invention is to provide a volume reduction device with high compression efficiency.
This is a device for compressing and volume-reducing a container containing radioactive solid waste, and as shown in the drawing, it is located on a pedestal (2) and controls the lateral movement and expansion of the container (1). a mold (3) for moving in and out of the mold, a press ram (4) for compressing and covering the container, means for advancing and retracting the press ram, in the illustrated example a hydraulic cylinder (5), a cylinder and a waste material. A means for feeding a container containing a container into the mold and taking out a compressed body; In this step, a rotary plate (42a5 and 8) which can freely rotate about its axis is attached to one or both of the part corresponding to the bottom of the mold and the tip of the press ram on the base plate, and a press ram is attached. A perforated tube (7) is provided at the center of the tip of the ram so that it can enter and exit the pushing ram, and the tube (7) is inserted into and out of the pushing ram with sufficient strength to make a hole in the container at the beginning of compression. However, the perforated pipe is adjusted so as to retreat without withstanding the resistance generated as the compression progresses, and the perforated pipe is connected to the air filter (9) through the air rear vibrator (43). The perforated tube (7) is suitably shaped like a thick syringe needle as shown in Figures 2 and 3. Adjustment of its entry and exit into and out of the push ram is as shown in Figure 2. To,
This can be done by using one or more =] files (71) and appropriately selecting their strength. The means for feeding the container containing the waste into the mold and taking out the compressed body includes a mold release mechanism that lifts the mold upward or pulls it downward relative to the receiver;
It may be advantageous to use a transport mechanism which forces the container and its compaction laterally, for example in combination with the pusher described above. When lifting the mold upward, the above-mentioned JP-A-63-
The method disclosed in No. 27800 can be used.

[For use]

After investigating the cause of the breakage of the perforated pipe in the above-mentioned compression volume reduction equipment recommended by JAERI, the inventor found that the perforated pipe found in the container hits, for example, a strong metal part at the end of compression. I learned that the main causes were the excessive force applied and the twisting of the container during the compression process, which exerted lateral force on the open tube. The solution to the former problem is to allow the open-hole tube to retreat into the push ram when a force above its limit is applied, and to address the latter problem, the container that is being compressed is The purpose is to prevent the twisting from becoming a force acting in the lateral direction. This was achieved through a structure in which a single open-hole tube was installed on the central axis of the pressing ram, and the ingress and egress of the tube was adjusted according to the force applied to it. It was also found that when the mold, its bottom part and the extrusion ram tip are all fixed, they create forces resisting compression through the contact between the mold and the container, which reduces the compression efficiency. Therefore, the inventor thought that it would be more advantageous to make the surface of the compression device facing the container rotatable and allow it to twist, and when he introduced the above-mentioned rotating plate, he was able to significantly reduce the difficulty of compression. As can be easily understood from this mechanism, rotating plates can be installed both above and below the container, on the Zunawara base plate, at the bottom of the mold, and at the tip of the press ram. Preferably, but
Even just one is much more effective than not having one. If such a device is used to compress and reduce the volume of a drum containing radioactive solid waste, holes will be created in the container at the beginning of compression, and the air inside will be expelled as compression progresses, allowing the filter to pass through. During compression, the pressure inside the container does not build up and there is therefore no risk of rupture. If excessive forces are applied to the open-hole tube during the middle or end of compression, The twisting of the container that may occur during compression is avoided by the action of rotating plates placed in contact with the top and/or bottom of the container. , twisting slows down the compression,
The degree of compression that can be achieved is also not reduced. [Effects of the invention] If the apparatus of the present invention is used to compress and reduce the volume of radioactive solid waste, there is no risk of radioactive materials scattering, reducing the chance of workers being exposed to radiation and reducing the need for equipment for contamination control. Can be reduced. This device has a structure that is difficult to break and is highly durable.

[Brief explanation of the drawing]

FIG. 1 is a side view of an example of the compression and volume reduction device of the present invention, with a part thereof shown in cross section, without showing the overall structure. 2 and 3 both show the configuration of the main parts of the apparatus shown in FIG. 1, with FIG. 2 being a longitudinal sectional view and FIG. 3 being a bottom view. 1... Container containing radioactive solid waste 2... units
Plate 3... Mold Mold 4... Push ram 41... Push ram body 42... Rotating plate 43...
・Air vent pipe 5...Press ram advance/retreat means 6...Container and compressed body transfer means

Claims (3)

[Claims] (1) A device for compressing and reducing the volume of a container containing radioactive solid waste, including a mold located on a cradle and regulating the lateral movement and expansion of the container; A device comprising a push ram that moves in and out of the mold to compress the container, means for moving the push ram forward and backward, and means for feeding the container containing waste into the mold and taking out the compressed body. In this step, a rotary plate that can freely rotate around the axis thereof is attached to one or both of the part corresponding to the bottom of the mold and the tip of the press ram on the base plate, and an opening is provided at the center of the tip of the press ram. A hole tube is provided so that it can go in and out of the press ram, and the hole tube comes out of the press ram with a strength that is strong enough to make a hole in the container at the beginning of compression, but withstands the resistance that occurs as compression progresses. Adjust so that it moves backwards without
A compression volume reduction device for radioactive waste, characterized in that the perforated pipe is connected to an air filter through an air vent pipe. (2) The compression volume reduction device according to claim 1, wherein the adjustment of the opening and exit of the perforated pipe is performed by a coil spring. (3) As a means for feeding the container containing waste into the mold and taking out the compressed body, there is a mold release mechanism that pulls the container upward or pulls it downward relative to the mold cradle, and the container and 2. The compression volume reduction device according to claim 1, which uses a combination with a transfer mechanism for laterally pushing the compressed body.