DISPERSION MECHANISM OF COAGULATED PARTIC LES BY ACCELERATION OF A LIQUID IN A CONVERGENT NOZZLE - DISPERSION OF COAGULATED PARTICLES CONSISTING OF SAME-SIZE SPHERES

The mechanism of dispersion of coagulated particles consisting of same -size spheres in an accelerating liquid-flow field in a convergent noz zle was studied and the following results were obtained. 1) The disper sibility DS, which is defined as the ratio of the separation force bet ween particles in a coagulated particle F-d to the adhesion force betw een them F-a, was proposed. DS (=F-d/F-a) is a measure of difficulty o f particle dispersion (dispersion or separation takes place when DS>1) and is theoretically given as a function of primary particle diameter , morphology of coagulated particles, flow fields and adhesion force b etween particles. 2) Coagulated particles composed of standard PSL (po lystyrene latex) spheres (1.1, 1.9 and 5.2 mu m in diameter) were disp ersed in a convergent nozzle. It was found that the degree of dispersi on of coagulated particles observed with a microscope was well correla ted by DS under various experimental conditions.