GB2090180A

GB2090180A - Device for holding and transporting radioactive liquids

Info

Publication number: GB2090180A
Application number: GB8135524A
Authority: GB
Original assignee: Deutsche Gesellschaft fuer Wiederaufarbeitung von Kernbrennstoffen mbH
Current assignee: Deutsche Gesellschaft fuer Wiederaufarbeitung von Kernbrennstoffen mbH
Priority date: 1980-12-18
Filing date: 1981-11-25
Publication date: 1982-07-07
Also published as: BE891507A; FR2496962B1; DE3047697A1; FR2496962A1; DE3047697C2; GB2090180B; JPS57125387A

Abstract

A device for holding and transporting radioactive liquids, e.g. liquid wastes, comprises a material in which capillaries for absorbing the liquid are formed. The material may be directly processed into a product for final storage or disposal. The material used is preferably glass which can be used in the form of porous powdery glass particles, i.e. glass particles provided with capillaries, or in the form of glass blocks in which the capillaries are arranged in the form of a matrix, each block being formed with a central recess for the introduction of the radioactive liquid into the block. <IMAGE>

Description

SPECIFICATION A device for holding and transporting radioactive fluids This invention relates to a device for holding and transporting radioactive fluids.

The difficulties and dangers which occur during the handling and the transport of radioactive fluids make great demands on the procedures and devices that are used for this purpose. Radioactive fluids can be transported for short distances by pipe lines from the place where they originate to plant where they can be processed further.

However, where the distances between the place where the radioactive fluid originates and the plant where it is further processed are greater, the radioactive fluid must be filled into containers and transported over public traffic routes. In order that such transport can take place the containers may comply with legally prescribed safety regulations and must have a traffic law permit. It is more difficult and expensive to transport radioactive materials in the liquid state than in the solid state.

Therefore, it is as far as possible preferred to transport radioactive materials in the solid or quasi-solid state.

It has been proposed to solidify radioactive fluids by converting them into a radioactive calcine or residue which can then be filled into containers for transport.

It is a disadvantage of this procedure that at the place where the radioactive fluids originate, additional expensive technical devices, such as evaporators or calciners, are required in order to produce the calcine or residue, and that radioactive waste gases have to be treated during the production of the calcine or residue.

Furthermore, a process has been developed for producing porous glasses by fusing radioactive solutions into a glass composition at low temperature to produce a material which has a high resistance to leaching out of the radioactive constituents. For this purpose, for instance, a porous glass powder is produced from an alkali borosilicate glass rich in silicate, the glass being separable at a temperature of 1400"C, into two phases with high and low silicate contents respectively. The phase with the low silicate content can be completely dissolved by treatment with acid so that a porous powder remains which, because of its high silicate content, has in connection with radioactive fission products, a resistance to leaching out considerably greater than that of borosilicate glass.

It is an object of the present invention to provide a device in which radioactive fluids can be transported simply and safely. The device is preferably such that further processing of the radioactive fluid into a final product which can be stored is possible without substantial further expenditure.

According to the present invention there is provided a device for holding and transporting a radioactive fluid, wherein a material suitable for holding and transporting a radioactive fluid is formed with capillaries for the fluid.

In the use of the present device, a kind of quasisolidification of the radioactive fluid takes place due to the binding of this fluid in the capillaries by surface tension without a change of state of the fluid occurring. The disadvantages of the techniques hitherto known are reduced or avoided and considerable advantages are obtained with respect to safety and the ability to handle the radioactive fluids in a technically simple manner.

The material from which the present device is made is preferably glass and this has the advantage that the demands regarding safety techniques for the transport of radioactive fluids can be met and that furthermore the radioactive material can be processed into a final product for storage without any further additional intermediate technical steps. The composition of the glass can be selected in such a way that the material corresponds to the materials of the later solidification process so that the final vitrification for final storage is made possible directly.

The glass is conveniently in the form of porous powdery glass particles, i.e. glass particles provided with capillaries. This has the advantage that a larger surface is made available for binding the radioactive fluid. By suitable production methods, the dimensions of the hollow spaces of the capillaries can be selected as required in relation to the surface tension and the density of the radioactive fluid.

In another embodiment of the present device, the glass has the form of glass blocks in which the capillaries are arranged in the form of a matrix, the glass matrix consisting of a plurality of individual capillaries the inside diameters of which are selected in accordance with the properties of the radioactive fluid.

The glass blocks are preferably provided with recesses for introducing the radioactive fluid into them or each glass block has a central recess for introducing the radioactive fluid into it, such recesses facilitating filling the blocks with the radioactive fluid.

Expedientiy, the material in the form of the powdery glass particles or the glass blocks is or are arranged directly in a transport container or in one or more compartments of a transport container.

In order to guarantee the necessary removal of heat from the transport container, the walls of the transport container or walls forming the compartment or compartments of the transport container are made as heat conducting walls.

It may be pointed out that the quasi solidification of the radioactive fluid, and thus its absorption by the glass particles or the glass blocks, can take place before or after the glass particles or the glass blocks have been loaded into the transport containers or into compartments which can be inserted into the transport container or removed directly therefrom.

In order to enable the invention to be more readily understood, reference will now be made to the accompanying drawings, which illustrate diagrammatically and by way of example two embodiments thereof, and in which: FIGURE 1 is a perspective view of a transport container having four interior compartments filled with powdery glass particles, and FIGURE 2 is a perspective view of a transport container having four interior compartments filled with glass blocks.

The same reference numerals are used to denote similar parts in Figures 1 and 2.

Referring now to the drawings, each Figure shows a transport container 2 the interior 4 of which is divided into four smaller compartments by separating walls 6 of heat-conducting material so that these separating walls serve to remove heat from the interior of the container. The four inside spaces are filled with porous powdery glass particles 8 (Figure 1) or with glass blocks 10 (Figure 2) which are formed with a capillary matrix (not shown). Each glass block 10 has a central recess 12 into which the radioactive fluid may be introduced and which is in communication with the capillaries.

The radioactive fluid is introduced into the container using dosing devices in such a way that only a predetermined quantity of radioactive fluid corresponding to the holding capacity of the porous powdery glass or of the porous glass block is filled into each compartment.

Claims

1. A device for holding and transporting a radioactive fluid, wherein a material suitable for holding and transporting a radioactive fluid is formed with capillaries for the fluid.

2. A device as claimed in Claim 1, wherein the material is glass.

3. A device as claimed in Claim 2, wherein the glass is in the form of porous powdery glass particles.

4. A device as claimed in Claim 3, wherein the glass particles are formed with capillaries.

5. A device as claimed in Claim 2, wherein the glass has the form of one or more glass blocks in which the capillaries are arranged in the form of a matrix.

6. A device as claimed in Claim 5, wherein each glass block is formed with a recess for introducing the radioactive fluid into the block.

7. A device as claimed in Claim 5 or 6, wherein each glass block is formed with a central recess for introducing the radioactive fluid into the block.

8. A device as claimed in any one of the preceding claims, wherein the material is arranged directly in a transport container or in one or more compartments of the transport container.

9. A device as claimed in Claim 8, wherein the walls of the transport container or the wall(s) forming the compartment(s) of the transport container are made heat conducting.

10. A device for holding and transporting a radioactive fluid substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawings.