Abstract: A storage tank for radioactive fissile material solutions. The tank comprises at least one cell containing a radioactive solution and a solid neutron-absorbing material while preventing any risk of criticality. A network of substantially vertical tubes is arranged within said cell and metal walls completely separate the radioactive solution from the solid neutron absorbing material. Said tubes contain the neutron absorbing material and are located in compartments defined by the metal walls throughout the radioactive solution. Said tank occupies a reduced floor space.

Abstract: The guiding device comprises a body, the size of which corresponds to that of a fuel assembly, intended to rest on the lower core plate (20), equipped with holding means intended to be grasped by an assembly-handling machine, extended downwards by means (18) for positioning it on the lower core plate at an assembly location adjacent to the one intended to receive the assembly to be guided, and two wings (30) carried by the bottom part of the body, forming an angle of 90.degree. in a horizontal plane, each one having an inclined guide face (32) ending at the bottom above the location intended to receive the assembly when the device is in place. Each wing (30) can be retracted, starting from a deployed state, towards a position in which it is withdrawn within the horizontal size of the body.

Abstract: A compacting method and apparatus particularly adapted to compacting hazardous materials, and in particular radioactive waste, in which a container (1, 1', 1", 1"') is compacted inside a compacting skirt (20) by cooperation between a support surface (7) on which the compacting skirt (20) with the container (1') is placed and a compactor (9) disposed faing the support surface (7) and displaceable along a vertical axis inside the compacting skirt (20). According to the compacting method the compacting skirt (20) containing the container (1, 1', 1", 1"') is moved in translation, in particular between a loading station (I) for loading the container (1), a compacting station (II) where the container (1') is compacted, and an unmolding station (III) for unmolding the compacted container (1") and for evacuating the compacted container (1"') downwards.

Abstract: The invention relates to a process for the electrochemical oxidation of Am(III) to Am(VI), usable for separating americium from spent nuclear fuel reprocessing solutions.The process consists of adding to the aqueous nitric solution (17) containing the Am(III) a) heteropolyanion able to complex the americium, such as potassium phosphotungstate and b) the Ag(II) ion for oxidizing Am(III) being converted into Ag(I), and subjecting the solution to an electrolysis under conditions such that electrochemical regeneration takes place of the Ag(II) ion from the Ag(I) ion obtained during said oxidation.After oxidizing Am(III) to Am(VI), it is possible to extract the latter in an appropriate organic solvent.

Abstract: A system for the surveillance or monitoring of an industrial installation (in particular a nuclear installation) making it possible for at least one operator to carry out rounds, the system having at least one central terminal (22) associated with a transmitter/receiver (23), identification labels located at different plotting or recording or acquisition points (12) at predetermined locations within the installation, and at least one portable terminal (26) available to each operator and associated with a data transmitter/receiver (27) for communicating with the central terminal and a label reader (28). These labels include electronic labels, whose content can be read and modified by writing. Electronic labels located on automatic equipment to be controlled, in each case contain a base for updated data relating to the characteristics of the equipment. The label reader associated with each portable terminal also permits a writing in the electronic labels.

Abstract: A method and apparatus for checking the surface state of one face (2) of a solid (1) in order to locate shape defects which may be present therein. The observation of the face to be checked takes place by means of photography using a large field video camera (3) and a small field video camera (4). The size of the located defects is measured by an optoelectronic sensor or probe (11). The apparatus can be controlled by an operator or can have automatic control.

Abstract: A unit for the rapid and reliable decontamination of containers containing contaminated liquids. The apparatus automatically receives, opens, empties, rinses and drys the containers individually. The containers may be sorted as a function of their residual contamination. The containers may optionally be crushed at a temperature at which they are rendered fragile. The containers, whether uncrushed or crushed, are then put into storage or waste canisters. The soiled or contaminated liquids are received by separate collectors.

Abstract: A process for treating an aqueous solution mainly containing nitric acid and hydrofluoric acid. The process involves distilling to provide an aqueous solution concentrated in nitric acid and hydrofluoric acid for the separation thereof, then separating by distillation.

Abstract: A method of compacting, without danger of ignition and/or explosion, metal waste that is liable to ignite and/or explode while being compacted. The method comprises in compacting a container that contains said waste and that is saturated in inert gas.

Abstract: Device for the extraction by pouring at a regulatable flow rate a molten material in a cold structure melter. The melter has at least one part of a floor around a pouring orifice cooled by a flow of water and a heat source able to melt the material to be melted. An orifice is provided in the floor of the melter, whose diameter D is equal to or larger than the thickness H of the wall forming the melter. A metal sleeve is provided, whose base has a shoulder which can be adapted to the side walls of the orifice. The sleeve has a central passage forming the pouring tube for the molten material and a clearence is provided between the side walls of the orifice and the base of the sleeve in order to receive an insulating material between the sleeve and the cold floor of the melter. A device is provided beneath the floor of the melter having a cooled, sliding blade, equipped with an actuator controlling its movement in translation along the orifice, thus determining its more or less large opening or closing state.

Abstract: A receptacle (59) is provided which includes a flask (22) surrounded by a casing (23) able to slide into a pipe by pneumatic means. A composite element (33, 40) formed of all of one piece is used to close both the openings of the flask and casing by means of screwing. These improvements and others render the receptacle extremely suitable for a large number of measurements carried out in shielded analysis boxes for dangerous samples, especially radioactive ones.

Abstract: The invention relates to a process and an installation for the destruction of organic solutes, particularly complexing agents, present in an aqueous solution such as a radioactive effluent.According to this process, the aqueous solution undergoes electrolysis in a cell (1) comprising a working electrode (5.sub.1, 5.sub.2, etc.) by applying to said electrode an adequate potential for destroying the solutes by electrolytic oxidation and periodic modification takes place to the potential applied or to the passage direction of the current passing through the cell so as to periodically carry out a regeneration of the working electrode.The solutes can be organic acids such as formic acid, dihydroxymalonic acid or oxalic acid.

Abstract: In order to automatically take samples of radioactive liquids contained in jugs (14) sealed by screw caps, an assembly is proposed which consists of a gripping module (20) for gripping and holding the jug, a module (22) for opening and closing the jugs, and a sampling module (24). The gripping module (20) brings each jug in from of the opening and closing module (20) and fulfils a holding function during the screwing and unscrewing of the cap or plug and during the sampling operation or operations. The sampling module (24) carries out the sampling operations by means of an end piece (138) for the suction and transfer of the liquid into a container (26) for analysis purposes.

Abstract: In order to reduce liquid effluents and solid waste in an analysis chain receiving liquid samples contained in jugs (16), the proposal is to automate all the operations performed in analysis units or boxes (10a, 10b). Moreover, when the sampling operations necessary for the analyses have been carried out in the analysis units (10a, 10b), the jugs can be automatically dispatched to a recycling apparatus (52).

Abstract: The invention relates to the dissolving of plutonium and/or other radioactive elements in an aqueous solution by microwave heating.According to the invention, solid or liquid products containing plutonium and/or other radioactive elements are introduced into a container (7) containing an acid solution, comprising hydrofluoric acid and nitric solution, followed by the microwave heating of the solution containing these products using a chamber or tank (5) placed in a tight enclosure (1), which is supplied with microwaves by means of a coaxial cable or a waveguide (11) connected to the generator (9) located outside the enclosure.The solid products can be plutonium dioxide PuO.sub.2 or organic or mineral radioactive waste materials such as gloves, cellulose products, ion exchange resins, etc. The liquid products can be contaminated organic solvents such as tributyl phosphate in dodecane.

Abstract: Device for filling a receptacle (R) by lowering it onto a needle (5) which pierces it. The portions of the installation adjacent to the bottom of the receptacle (R), which could be polluted by ill-timed projections of liquid from the needle, are washed and dried by nozzles (27, 28, 29) for washing the zones potentially reached by the projections, as well as the needle (5) itself, this washing and drying being followed by drying by suction orifices (38).

Abstract: A device for storing cylindrical objects, such as small containers (14) containing radioactive material samples, includes one or more superimposed rotary racks (30, 30'). Each of the racks has circumferentially distributed cavities (32, 32') in which the objects are received. The cavities are radially outwardly open with respect to the vertical rotation axis of the racks (30, 30'). Moreover, their axis is inclined so as to intersect the rotation axis above the cavity. Thus, an accidental escape of the objects is prevented.

Abstract: This probe, which is to be placed in a uniform magnetic field, comprises an ion acceleration zone, a circular sector (6) polarized so as to create in the zone an accelerating electric field, an ion collector (8), a conducting grid (36) at the entrance to the zone for fixing the potential at said entrance, the distance between said grid and the sector being adequate to ensure that the ions drift into the zone from their incidence position on the grid. The sector has an entrance slit (38) displaced with respect to said incidence position in order that the electric field is uniform in the acceleration zone.

Abstract: The invention relates to a process fop trapping gaseous ruthenium on polyvinyl pyridine, more particularly usable for recovering radioactive ruthenium from irradiated nuclear fuels.This process consists of contacting a gas containing ruthenium in gaseous form with an adsorbent (11b) constituted by a vinyl pyridine polymer or copolymer for fixing the ruthenium to the latter. The gas can be constituted by yapours from a concentrate of fission products containing ruthenium, which has been heated (at 31) in the presence of an oxidizing agent for volatilizing the ruthenium.

Abstract: The invention relates to a process for the separation of at least one element such as Nb, Sb, Ce+Pr, actinides and elements from groups VIIb and VIII of the Periodic Classification of Elements from aqueous solutions resulting from the reprocessing of spent nuclear fuels.This process consists of contacting said aqueous solution with a solid resin based on a vinyl pyridine polymer or copolymer and separating from said solution the resin used for fixing said element or elements.The resin is in particular a poly(vinyl-4-pyridine) powder in crosslinked from and the separated elements are e.g. ruthenium, rhodium, palladium, technetium, manganese, cobalt, iron, nickel, cerium and praseodymium.