W. Machowski et W. Balachandran, DISPERSION AND TRANSPORT OF COHESIVE LACTOSE POWDER USING TRAVELING-WAVE FIELD TECHNIQUE, Powder technology, 99(3), 1998, pp. 251-256
The main objective of this research was to study transport phenomena o
f cohesive powders using the travelling wave field technique. In the l
iterature only limited attention has been paid to the transport of coh
esive powder materials using this technique, although it has been succ
essfully used with non-cohesive powders. Cohesive powders are generall
y much more difficult to transport due to short range molecular forces
as well as electrostatic forces. Such forces usually cause agglomerat
ion and adhesion of particles which may significantly impede the flow.
In this study, an optimisation process is presented for selecting an
appropriate electrode arrangement for levitation and transportation of
a given powder. Computer modeling was used to establish how the shape
and geometry of the electrodes influence the transport of a particle
having a given size and charge-to-mass ratio. Based on the modelling r
esults a flat-bed travelling wave panel with optimised strip electrode
s arrangement was constructed and used in the experimental study. Cohe
sive lactose powder (150 mesh, D-4,D-3 = 80 mu m) was successfully dis
persed and transported using this panel arrangement. Particle trajecto
ries were examined using a CCD camera with telemicroscopic lenses inte
rfaced with a computer controlled image grabbing system. (C) 1998 Else
vier Science S.A. All rights reserved.