Rheological characterization of mineral suspensions using a vibrating sphere and a rotational viscometer

Document Type


Publication Date



A new technique has been developed for the characterization of the rheology of mineral slurries into Newtonian and non-Newtonian flows. It utilizes a rotating type viscometer to measure apparent viscosity at a low shear rate, and a vibrating sphere type viscometer to measure the apparent viscosity at a high shear rate. Special precautions were taken to allow measurements of apparent viscosity of rapidly settling mineral suspensions. Both the viscometers are able to measure apparent viscosity as low as one mPa · s (millipascal-seconds) (1 mPa · s = 1 centipoise), which is the approximate room temperature viscosity of water. Because the vibrating sphere viscometer operates at a much high shear rate than the rotating viscometer, the two instruments together can determine the shear-rate dependency of the viscosity. Ground silica of -65 mesh size was used to prepare slurries in water at different percent solids. The apparent viscosity of each slurry sample was measured simultaneously by both viscometers, and the results were compared with each other. In this way, it was determined that silica slurries, for a given particle size distribution, between 0-70% solids by weight in distilled water have Newtonian flow behavior.

Publication Title

International Journal of Mineral Processing