Settling test and size determination - Loading effect in settling of unflocculated particles and their size distribution

Abstract

Background. A loading effect has been observed in which the settling of fine particles is accelerated on account of being dragged down by the coarser ones. in this;phenomenon the basic flow units are not individual particles, but aggregates. Methods. A settling test was carried out in a 500-ml graduated cylinder filled with suspension of required solid concentration. Slimes generated from the processing of iron ore and granite ore were used. Results and Conclusions. The sedimentation data in the dilute concentration regime follow the Michaels and Bolger equation expressing maximum settling rate in terms of Stoke's settling velocity and initial solid concentration for this type of settling. The kinetic data have been used to derive the degree of aggregation and average particle size. The computed values match fairly well with the measured ones. (C) Munksgaard, 1996