IL23084A

IL23084A - Process for the removal,within a small space,of liquid samples placed in containers and device for the practical application of the process

Info

Publication number: IL23084A
Application number: IL23084A
Authority: IL
Original assignee: Commissariat Energie Atomique
Priority date: 1964-03-06
Filing date: 1965-03-02
Publication date: 1968-08-22
Also published as: GB1095466A; ES310148A1; NL6502574A; CH432668A; US3350565A; BE660164A; LU48078A1; FR1401234A; DE1277024B; SE315344B

Description

COMMISSARIAT A l/ENERGIE ATOMIQUE The present invention relates to the removal, in a small volume, of samples of noxious solutions which are placed in containers. rm · · . -, -, tne removal, of The invention is more especially concerned with/ samples of radioactive solutions after these latter have been analyzed in a pilot plant, said samples being, for example, placed within flasks of polythene which are in. turn enclosed within capped transporter tubes which are also formed of polythene, said transporter tubes being employed for transferring samples from the hot cells to the laboratories, then from the laboratories to a decontamination plant for conditioning and subsequent removal .

When the analyses to be performed have been completed, the sample flasks must be opened and their contents removed. Since the rubber plug which closes each sample flask is secured by means of an aluminium capsule which is crimped-on for reasons of safety, the flasks can be emptied only by means of a mechanical process which consists either in removing the caps, in splitting open the flasks or in an unclamping operation. It is then necessary to decontaminate the interior of the flasks which have contained a radioactive liquid, then to condition the flasks, containers and caps for subsequent removal. It is in fact essential to separate the radioactive liquids which are eliminated in the form of liquid effluents from the solid wastes which are stored in special" drums prior to separate processing.

The main solutions which have been adopted up to the present time and which consist either in emptying after de-capping or in mechanical splitting have not problems involved in the design and development of simple mechanical equipment, in the dangers of contamination of the processing area as a result of the projection of radioactive liquids, in the difficulties attached to the decontamination of flasks and, finally, in the substantial volume required for the storage of solid wastes.

The primary aim of this invention is to provide a process for the removal of waste products which conforms to a wide range of practical requirements more effectively than has been possible heretofore, especially insofar as the disadvantages referred-to in the foregoing are overcome by said process „ The invention mainly consists of a process in which liquid samples and their contaminated containers are cooled, prior to breaking-down, to a temperature such that said containers are embrittled and the activated liquids present therein are frozen, the fragments resulting from the breaking-down or crushing operation being then reheated, washed, conditioned and discharged in a storage drum .

The invention also consists of a device for the practical application of the process comprising successively a compressed-air conduit for the supply of containers, an inclined ramp, a cooler through which liquid nitrogen is circulated, a crusher, a washing tank, a device for conditioning solid wastes, means for discharging solid wastes and liquid effluents, the complete apparatus being disposed within a steel-walled, leak-tight enclosure which is lead-shielded and fitted with viewing windows, handling grabs, access doors, lock chambers, lighting means and all other known arrangements which are necessary. main arrangements, in certain other arrangements which are preferably employed at the same time and which are to be considered separately or in combination, viz : - said containers are formed of polythene, - said containers are brought within said cooler to a temperature of approximately - 150° C, - said device additionally comprises, within said steel- walled enclosure, a lifting apparatus which serves for emergency operation in the event of failure in the normal supply of containers., The main advantages which result from the application of the process and device in accordance with the invention are as follows : - ease of operation of the device which is largely static, - reduced contamination hazards, the active liquids being frozen at the time of crushing, - improvement of decontamination by elimination of internal corners of flasks which are always difficult to clean, - small storage volume which is reduced in the proportion of to 1, A clearer understanding of the present invention will in any case be gained from the complementary description which follows below as well as from the accompanying drawings, it being understood that said description and drawings are given solely by way of indication and not in any limiting sense .

In the accompanying drawings : - Fig. 1 is a vertical sectional view along line a-a of Fig. 2 and showing a device in accordance with the invention, - Fig. 2 is a vertical sectional view along b- wit f m nt r o w the crusher.

As shown in these figures, the complete device in accordance with the invention is placed within a steel-walled enclosure 1 which is in turn surrounded by a lead shield 2.

The full containers such as the container 3 are admitted at 4- at the top of the enclosure 1 and are directed by means of an inclined ramp 5 towards a cooler 6 in which they remain for a certain length of time.

Liquid nitrogen which is circulated through said cooler is admitted through the tube 7 and discharged through the tube 8 and maintains as a result of the evaporation thereof a temperature of approximately - 150 ° C within the cooler „ After passing out of the cooler, the containers formed of polythene which has thus been embrittled are directed together with their frozen contents towards a crusher 9 provided with two series of discs such as 10 which are designed to crush all the containers and reduce them to small fragments. The discs such as the disc 10 are driven in rotation by a motor 11 through the intermediary of a driving belt 12 , a flywheel 13 and a shaft 14 which passes through the shield 2 and the enclosure 1 in leak-tight manner by virtue of seals 15 , 16 and 17 „ The crushed fragments fall through a funnel 18 placed beneath the crusher 9 into a washing tank 19 in which the liquid effluents are then separated from the solid wastes. Three water-supply pipes such as the pipe 20 and acid-supply pipes such as the pipes 21 and 22 terminate within the top portion of said tank 19 and, as will be apparent, also pass through the enclosure 1 in leak-tight outlet of the tank 19 so as to complete the washing of the crushed containers by agitation. The liquid effluents will be discharged through the pipe 24 which is fitted with a filter cock 25 - The solid wastes, which are considerably reduced in volume, will be discharged through a conduit 27 by means of compressed air which is admitted through an intake 26, There can also be disposed within the interior of the enclosure 1 a capping device 28 and a container lift 29 which will serve for emergency operation in the event of failure in the normal supply of containers at 4.

Provision can finally be made in the enclosure 1 for an access door 30 which is actuated by a jack 31 , viewing windows such as the window 32 , a lock chamber 33 > a passageway 3 providing access to 'the crusher, a handling grab 35 which is mounted on a universal joint assembly 36 , a device for providing ventilation through the openings 37 ? as well as lighting means and all other conventional arrangements which may prove necessary.

As will be readily understood, and as has in any case been brought out in the foregoing, the present invention is not limited in any sense to the example of construction or to the mode of application which have been more especially described and illustrated but is intended, on the contrary, to include within its scope all alternative forms, particularly in regard to the removal of any liquid samples of a hazardous but not necessarily radioactive nature which are placed in containers.

Claims

EAVISJ® BO particularly described and aeoertalned the nature of our said invention and in what manner the same le to be ^e f^naed, we declare that what wc claim ie:-

1. Process for the removal, in a small volume, of samples of noxious liquid solutions which are placed in containers, characterized in that liquid samples and their contaminated containers are cooled prior to crushing to a temperature such that said containers are embrittled and the liquids present therein are frozen, the crushed in a vacuum fragments "being then re-heated, washed, conditioned/and discharged in a storage drum.

2. Process in accordance with Claim 1,' characterized in that said containers are formed of polythene.

3. Process in accordance with Claim 1, characterized in that said containers are brought within a cooler to a temperature of approximately - 150° C.

4. Device for the practical application of the process in accordance with Claim 1, characterized in that it comprises a compressed-air conduit for the supply of containers, an inclined ramp, a cooler through which liquid nitrogen is circulated, a crusher, a washing tank, a device for conditioning solid wastes, means for discharging solid wastes and liquid effluents, the complete apparatus being disposed within a steel-walled, leak-tight enclosure which is lead-shielded and fitted with viewing windows, handling grabs, access doors, lock chambers, lighting means and all other known arrangements which are necessary.

5. Device in accordance with Claim 4, characterized in that it additionally comprises within said steel-walled enclosure, a lifting apparatus which serves for emergency operation in the event of failure in the normal supply of containers . B „ 1002 - 3

6. Process for the removal, in a small volume, of samples of noxious liquid solutions which are placed in containers, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings .

7. Device and apparatus for the practical application of said process, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings. !ated bie let day of Jiarcli, 1965 WOT the Applicaate B 1002-3