The effect of impeller pumping and fluid rheology on solids suspension in a stirred vessel

Pumping velocities of different impellers were measured using laser Doppler velocimetry. It was found that there is a link between impeller pumping ca pacity and the S parameter in the Zwietering correlation. Measurements show ed that N-js increases with impeller spacing for dual impeller configuratio ns. A dual-impeller configuration shows less sensitivity to solids loading change than a single-impeller configuration, and the change in N-js is larg er for small impeller spacing than for large impeller spacing. An increase in slurry cloud height and a reduction in N-js resulted at a small increase of non-Newtonian viscosity.