Transient behaviour of polymer-induced flocculation

Abstract

The transient behaviour of polymer-induced flocculation is examined theoretically. The present study, which takes the collision efficiency into account, is an extension of the conventional analysis. Here, the kinetics of the adsorption of polymer molecules onto the surfaces of colloidal particles are incorporated into Smoluchowski's flocculation mechanism. Also, unlike the classical approach, which assumes that the adsorption of polymer molecules onto the surfaces of colloidal particles achieves its steady state instantaneously, the transient nature of the collision efficiency is discussed. The temporal variations of the number of primary particles, the mean and the variance of the floc size distribution, and the mean density and porosity of the flocs are derived.