ON HORIZONTAL VIBROFLUIDIZATION OF SILICA
NANOPARTICELS
Wei Zhang
School of Chemical and Biomolecular Engineering, the University of Sydney, NSW, 2006,
Australia
Email: zhangwei811017@hotmail.com
Abstract
An experimental study was performed to investigate the process of vibration-assisted
nanoparticles fluidization. Fluidization characteristics were assessed by observing pressure
drop, bed expansion and bed collapse behavior at vibration frequencies between 0 Hz and 34
Hz, for silica nanoparticles with particle densities between 25.25 kg/ m 3 and 38.29 kg/ m 3 ,
primary size between 7 and 16 nm. Two modes of nanoparticle fluidization behavior were
observed:
i.
Agglomerate particulate fluidization (APF), which is smooth, occurs with extremely
high bed expansion, practically no observable bubbles
ii.
Agglomerate bubbling fluidization (ABF) which results in limited bed expansion
with large bubbles rising quickly through the bed.
The transition between particle and bubbling modes occurred at different vibration intensities
for each type of particle, however in all cases, smooth agglomerate particulate fluidization
was observed at vibrational frequencies greater than 16.7 Hz. This is much lower than
previous studies of assisted nanoparticle fluidization, and suggest that vibration assisted
fluidization is a viable technology for the large scale processing (e.g. reacting, dispersing, or
coating) of nanomaterials.
Keywords: agglomerates, nanoparticles, vibration, fluidization, silica