Experimental evaluation of effect of continous phase rheology on sedimentation behaviour

T. Sobisch*, D. Lerche, LUM GmbH, Germany

Separation processes basically can be described by extended Stokes law taking into account hindrance. To deduce behaviour under accelerated gravity in centrifuges one can assume that separation velocity scales linearly with acceleration in Newtonian fluids. Situation in non-Newtonian fluids is much more complicated.

The paper experimentally investigates settling behaviour starting from simple dispersions to more complex ones. Fluids investigated cover media from plain water, over solutions containing viscosifier, solutions of biopolymers, including media with shear thinning behaviour and yield point. Besides higher complexity of rheology behaviour rheological additives can also trigger flocculation.

The relation between settling at gravity and enhanced gravity is established. Determination of the distributions of settling velocity is used as tool for comprehensive description of settling behaviour as function of composition of fluid phase and acceleration applied...

Session: L2 - Sedimentation Analysis
Day: 11 October 2016
Time: 13:00 - 14:15 h