Rheological behaviour of mineral (clay) suspensions

Abstract

In this research, a rotating cylinder viscometer was designed and fabricated to study the structure formation of particles in a mineral suspension and its influence on the relative viscosity q/qo. It is known that the value q/qo is affected by the concentration of suspended mineral particles in an aqueous media. The relative viscosity q/qo thus obtained is related to the volumetric concentration of suspended particles by the equation q = qo + k(f>, where the value k depends on particle behaviour in aqueous medium and is related to the shape, zeta potential and the volume % of particles. By this method it is possible to classify the suitability of surface active minerals in mineral deposits on the basis of the k factor. The rotating cylinder viscometer consists of a cylinder, of known dimensions, immersed fully in a mineral suspension so that it can be rotated by applying a mechanical couple (Force X distance) acting on the cylinder by two identical falling weights which are tied to each other by an inextensible string. Initially the cylinder is made to rotate in water of known viscosity by fully immersing it, thereafter in the known suspension. From the rates of rotation, the viscosities can be compared and hence the k values.