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 capacity and the S parameter in the Zwietering correlation. Measurements showed that N_js increases with impeller spacing for dual impeller configurations. A dual-impeller configuration shows less sensitivity to solids loading change than a single-impeller configuration, and the change in N_js is larger 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.