Patent Number: 044144750
Section: summary

The invention relates to a shielding container for storing weak to medially active waste in a storage barrel or drum which is surrounded by the shielding container. Shielding containers of this type, such as those shown in German Published, Non-Prosecuted Application DE-OS 27 16 463 and German Petty Patent DE-GM 77 36 411, have heretofore been provided for permanent connection with the storage barrel, because the shielding container which was made in the form of a concrete pot was closed after insertion of the storage barrel by a concrete plug which was cast on top. This means that the volume and weight of the prior art shielding containers had to be also considered during a later transport and especially during the final storage. It is accordingly an object of the invention to provide a shielding container for storing weak to medially active wase, which overcomes the hereinafore-mentioned disadvantages of the heretofore known devices of this general type, and to obtain the shielding effect achieved by the known shielding containers only when required. The starting point is therefore the fact that the previously used final storage means are closed, so that the radioactive wastes must be in an intermediate storage facility, especially at the location where they are generated at least temporiarly. However, in nuclear power plants only relatively little space is available for this purpose, so that it is necessary to effect the storage in the most compact form. On the other hand, it is not permissible to "plug-up" the available space for long periods of time, or permanently. Rather, only a temporary storage is intended, until final storage facilitates are available, similar to previously used disposal in the abandoned salt mine Asse. With the foregoing and other objects in view there is provided, in accordance with the invention, a shielding container assembly for storing weak to medially active waste in a storage barrel, comprising a shielding container having a substantially or mainly square cross section surrounding the storage barrel, the shielding container having two pairs of oppositely-disposed sections or sides, one of the pairs having symmetrical projections formed thereon and the other of the pairs having chamfers formed thereon, and projections and chamfers effecting anchoring or interlocking of the containers when stacked close to each other. With shielding containers of this type, it becomes possible to fill the storage rooms in a much better way than with the known concrete pots which have a cylindrical outer shape. This applies not only for the stacking itself, but also for the strength achieved thereby, which, for example, must be capable of withstanding the lateral forces created by a possible earthquake. Furthermore, the shielding containers according to the invention can be used without a tight connection to the storage drums, because the required mechanical holding is provided by the new configuration of the cross section. In accordance with another feature of the invention, the projections and chamfers are disposed at corners of the shielding container. In accordance with a further feature of the invention, the projections and chamfers are in the form of symmetrical pairs. In accordance with an added feature of the invention, the shielding container has a clearance space or opening therein for receiving the storage barrel, the space extending through the total height of the shielding container. They can be assembled to form a stack without the storage drums, and can be filled with the storage drums. This facilitates handling, because the transport-weights are much less. In accordance with an additional feature of the invention, the clearance space has a cylindrical cross section and is centrally disposed in the substantially square cross section of the shielding container. In accordance with again another feature of the invention, the shielding container has top and bottom surfaces thereon, the surfaces having raised portions formed thereon and having recesses formed therein into which the raised portions fit. This is done because it makes it possible to also stack the shielding containers in a formation having severakl layers high on top of each other. In accordance with again a further feature of the invention, the raised portions are disposed at four corners of the square cross section of the shielding container. In accordance with again an added feature of the invention, the shielding container has undercuts formed therein, optionally at the recesses for attachment of gripper tools. In accordance with again an additional feature of the invention, there are provided reinforcements being disposed in the undercuts and extended into the shielding container, so that they are securely anchored there. In accordance with a concomitant feature of the invention, there is provided a storage chamber having straight walls with recesses formed therein, the projections being extended into the recesses. In this way an anchoring with respect to the building itself is achieved. The stacked shielding containers are thereby well anchored against lateral forces, such as forces generated by an earthquake. Other features which are considered as characteristic for the invention are set forth in the appended claims. Although the invention is illustrated and described herein as embodied in a shielding container for storing weak to medially active waste, it is nevertheless not included to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.