Abstract: A fluorine-generating electrolytic cell has the base 12 thereof insulated electrically by a layer 10 of plastics material such as PTFE which is held against the cell base by means of structure extending between cooling coils 24 of the cell and the layer 10.

Abstract: A carbon anode for a fluorine-producing cell is doped with a very fine dispersion of one or more transition metals, preferably nickel, vanadium and/or cobalt. The transition metal may be dispersed within the particles and/or the binder and is conveniently introduced in the form of an organic complex of the transition metal which decomposes during heat treatment of the consolidated mass of particles and binder.

Abstract: A flask for the transport of radioactive material comprises a hollow body containing a number of substantially identical members which cooperate to define a plurality of channels to receive radioactive waste containers. Each member is shaped to define substantially a half of an outer channel and a portion of a central channel. The members, conveniently aluminium bodies, are releasably secured to and in good thermal contact with the wall of the hollow body to provide for the conduction of heat generated within the waste containers.

Abstract: Cylindrical bodies 12 are brought into end-to-end relationship on a conveyor 30 (FIG. 7) by means of a second conveyor 42 running at a different speed, which may be greater than or less than the speed of conveyor 30. The conveyor 42 serves to flip misorientated bodies (see FIGS. 6C, 6D) into an orientation in which their axes are parallel to the feed direction C of the conveyor 30. A modified arrangement (FIG. 10) is described for bodies with length to diameter ratios of the order of 0.8:1. Other handling devices are also described for effecting single streaming of bodies starting from a randomly distributed array (FIG. 1), for separating bodies of different sizes from each other (FIGS. 2 and 3) and for transferring bodies from one conveyor to another (FIGS. 4 and 5).

Abstract: A process for removing radioactive species such as technetium from surfaces of components such as those formed from aluminum, and a process of treating the resulting effluents. For example, technetium trapped under an oxide layer present on an aluminum component is removed by removing the oxide layer with sulphuric acid, and treating the exposed technetium with a complexing agent such as citrate in the presence of an oxidizing agent. An oxide scavenger may be added to prevent reformation of the oxide layer. Actinides can be removed from the effluent by use of a chelating ion exchange material, and technetium by oxidation and use of a basic ion exchange material.

Abstract: A liquid treatment apparatus suitable for dewatering a radioactive sludge includes a cylindrical housing (14) open at one end and defining two ports (24, 26) for the sludge, one near the open end and the other at the closed end. A plug (30) locates in the open end of the housing and supports a module (44) comprising a sealed permeate-collecting chamber (46) through which extend a number of permeable-walled tubes (54), open at each end. The plug defines a header chamber (40) for the tubes (54) which communicates with the one sludge port (24); and defines an outlet duct (62, 38) for the permeate liquid. The apparatus can be installed remotely within a shielded enclosure (12), and the plug and module can be withdrawn without risking contamination of the permeate liquid.

Abstract: Apparatus, which can be a pulsed column, which functions as an efficient electrolytic cell having an efficient liquid-liquid extraction capability. The apparatus can comprise an anode/cathode assembly having a geometry such as to produce a substantially uniform current distribution across the cell.

Abstract: Matter is floated to the surface of a liquid by bonding ions to the surface of the matter to give the matter a charge, and forming a froth with the aid of a frothing agent having groups of opposite charge to the ions so that the frothing agent bonds to the matter and is carried in the froth to the surface of the liquid. By removing the froth the matter can be separated from any inert matter present in the liquid. The oxidation state of the surface of the matter may be changed before bonding takes place with the ions to one which facilitates that bonding. The matter can be particulate or dissolved ions. For example, uranium dioxide particles are oxidized with hydrogen peroxide, sodium carbonate added to produce a negatively charged uranyl carbonate complex and a froth formed with the aid of cetyl trimethylammonium bromide. Cationic groups in the latter bond to the uranyl carbonate complex causing the uranyl carbonate complex to be concentrated in the froth at the surface of the liquid.

Abstract: A container for nuclear fuel elements comprises an assembly of individual elongate compartments formed from releasably inter-engageable plates which are held together in a rigid assembly by spider members located at intervals along the length of the assembly. The assembly can include neutron absorbing material and can be encircled by bracing bands or straps.

Abstract: A dip tube, being a branch line from a gas pressure line, extends into a liquid in a vented bubble pot. The bubble pot comprises a precision bore vessel containing a displaceable body with an actuator, preferably a stepping motor, for moving the body arranged outside the pot. Displacement of the body changes the liquid level in the vessel to thereby regulate the pressure in the gas pressure line.

Abstract: A solvent extraction column (1) includes a distributor (3) for receiving feed liquid introduced into the column through an inlet port (2). The distributor (3) comprises an endless open channel (4) having a plurality of spaced apart apertures (10). The distributor is positioned adjacent the inlet port and feed liquid from the inlet port enters the channel and is distributed through the apertures (10) over the column.

Abstract: A centrifuge for the removal of solids from liquids, for example, the removal of solid fission products from dissolved nuclear fuel. The centrifuge is mounted behind a solid wall and is provided with a pivotable catch tray which cooperates with a feed inlet extending through the wall of a casing about the bowl of the centrifuge. The catch tray is pivotable between a first position at which it cooperates with the feed inlet to introduce feed liquid into the bowl and a second position at which it is removed out of cooperation with the feed inlet to permit withdrawal of the bowl from the casing through a removable plug in the wall.

Abstract: An end closure for a nuclear fuel flask in which the gate, which is movable between open and closed positions across an end of the flask, has first and second portions which are urged apart, conveniently by spring-loaded means. A door has upper and lower wedge-shaped members mounted on and releasably connected to the respective gate portions. In use, a displacement of the gate into or out of its fully closed position effects movement of one only of the gate portions and its associated door member. As the door members are wedge-shaped the other door member is urged into or out of sealing engagement with the end of the fuel flask.

Abstract: Bodies such as nuclear fuel pellets are formed into a stack in a stacking lane (34) and the length of the stack is measured at intervals by device (40) to determine if the partly-formed stack is drifting away from a target length. Pellets are issued into the stacking zone (34) by a selector mechanism (32), the input of which receives pellets from three lanes (24, 26, 28) containing oversize, undersize and intermediate size pellets and the pellets issued to the stacking lane (34) are selected under the control of microprocessor-based unit (18) according to the extent of any drift from the target value. The pellets in lanes (24, 26, 28) are derived from a common supply (12) following segregation by a diverter mechanism (22) controlled by unit (18) in accordance with length measurements made by measuring device (16).

Abstract: A drum to receive waste, in particular radioactive waste, and an encapsulating material such as cement is located on a vibratable platform beneath a charge chute. The platform is mounted on an inflatable support, conveniently a plurality of air cushions, operable to lift and maintain the drum in sealing engagement about the charge chute during filling of the drum. Vibration means on the platform vibrate the drum and its contents without breaking the sealing engagement.

Abstract: A fluid pressure operated device comprises a body adapted for moving an article and carrying magnets coupled to other magnets on a piston movable by fluid pressure in a cylinder. The body also carries spaced magnets and another piston carries spaced magnets. In a start position, one of said body magnets and one of said piston magnets are coupled. During normal operation the body and pistons move to another position in which the one body magnet operates a return sensor to return the device to start position. If an obstacle is encountered, the piston moves to release another sensor to reverse the device for a short stroke where a timer again reverses the fluid pressure to complete the stroke. Engagement with a second obstacle or a repeat engagement with the first obstacle returns the device to the start position and a warning alerts an operator to remove the obstruction.

Abstract: A selector mechanism for controlling transfer of articles from a plurality of upstream feed lines to at least one downstream feed line (104) comprises a plurality of transfer passages (114) each provided with a gate (106) and at least one stop (108). The gates (106) are operable to block the leading article in the respective transfer passages while the stops (108) are operable to arrest movement of a trailing article and hence the articles that follow it. Operation of the gates (106) and stops (108) is co-ordinated so that the stops are operative when the gates are operated to unblock the leading article. In this way, the number of articles freed for onward movement each time the gates are operated to unblock the path of conveyance can be controlled.

Abstract: A rotatable valve member having four ports is provided in a pneumatic conveyor system to permit the smooth docking of a carrier at a station. One port communicates through a branch duct with a main duct for the transport of carriers to the station. The remaining three ports communicate respectively with an exhauster, the docking station and atmosphere. The valve member provides communication between any two adjacent ports and during rotation controls the pressure balance on the carrier to ensure a smooth arrival at the docking station.

Abstract: In a process for the production of uranium tetrafluoride (UF.sub.4), uranic oxides, UO.sub.3 and U.sub.3 O.sub.8, are dissolved in dilute sulphuric acid (H.sub.2 SO.sub.4) and hydrofluoric acid (HF) is added to produce a uranyl fluoride-sulphate solution which is electrolytically reduced to uranous fluoride-sulphate complexes from which hydrated uranium tetrafluoride is precipitated by the addition of dilute HF at elevated temperature (preferably above 90.degree. C.). The uranyl fluoride-sulphate solution can alternatively be produced by dissolving uranyl fluoride in H.sub.2 SO.sub.4 or from uranyl sulphate solutions (derived from solvent extraction or ion exchange purification processes) conditioned with HF.

Abstract: Sampling apparatus has a syphon with a longer arm (19) leading to a needle sampling station (20) from which extends a shorter arm (21) of the syphon. Liquid flow structure including a reverse flow diverter (10) is used to produce forward and reverse flow in the syphon and, on reverse flow, reduced pressure at the needle is produced by the head N of liquid, and during reverse flow some liquid enters a sampling bottle (24) through the needle (22). The needle extends into a T-piece and has a lower end at or below the mid line of the lateral leg of the T.