The roles of particle and liquid properties in expression - an experimental study

The objectives of this work were to study effects of particle characteristics on the kinetics of the compression, consolidation and drainage processes. Work has been carried out on a range of solid/liquid mixtures; in each case the mixture was characterised in respect of its particle size and shape, the zeta potential associated with the particle and the ionic strength of its solution environment, and the resulting aggregation of the particulate phase. Expression experiments were carried out in a specially designed piston press and in a scaled-down version of an industrial horizontal tube press. Subsidiary experiments included numerous jar sedimentation tests and a limited number of filtration tests. The data presented highlight the important experimental parameters and serves to illustrate those factors which should be considered by the process engineer when selecting/designing separation equipment.