Method and apparatus for adding and mixing second cohesive powders in a fluidized bed blender

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)