[en] Fluidized powder is discharged from a fluidizing vessel into a container. Accurate metering is achieved by opening and closing the valve to discharge the powder in a series of short-duration periods until a predetermined weight is measured by a load cell. The duration of the discharge period may be increased in inverse proportion to the amount of powder in the vessel. Preferably the container is weighed between the discharge periods to prevent fluctuations resulting from dynamic effects. The gas discharged into the container causes the pressures in the vessel and container to equalize thereby decreasing the rate of discharge and increasing the accuracy of metering as the weight reaches the predetermined value. (author)

[en] Injection and uniform dispersion of a second cohesive powdered ingredient or ingredients having hydrophobic, hydrophilic or hydroscopic properties into a fluidized bed of UO₂ powder is effected by impinging the second ingredient against a deflection plate 21 mounted within the fluidized bed. The apparatus also includes an eductor, a pressurised vortex mill 11 and a pneumatic conveying system. Before entering the fluidized bed, the second ingredient is entrained in a gas and conveyed under pressure to the vortex mill 11 where the particles of the second ingredient are propelled radially outwardly through channels 28 and collide against tungsten carbide impact, blocks 32 causing comminution of the particles. (author)

[en] The invention concerns improvements made to the mix of UO₂ powders and a second type of cohesive powders by using a fluid bed mixer. A fluidized bed of UO₂ is first formed in the tank of the apparatus, then the second constituent is introduced into the vessel in powder form under pressure, causing it to hit a deflecting plate, placed inside the fluid bed, to distribute the second constituent evenly