SUSPENSION OF SOLIDS BY MECHANICAL AGITATION

An expression for the minimum pick up velocity of the fluid, i.e., the minimum velocity required to initiate the suspension of solids in a mechanically agitated system has been obtained based on the flow pattern, system geometry and physical properties of the two-phases involved. The criterion for the suspension of solids is given. The minimum impeller speed theoretically obtained from the above expression is compared with the experimental values and a suitable correction factor is incorporated in the former in terms of the concentration of solids. The generalised correlation thus obtained agrees well with a number of systems investigated. © 1969.