Variability of shear yield stress – measurement and implications for mineral processing

Abstract

At high concentrations, mineral tailings exhibit solid-like behavior up to a critical shear stress, the shear yield stress , which must be exceeded before flow may occur. The magnitude of has a significant influence upon a wide range of important mineral processing operating parameters, including pipeline pressure gradient, thickener operation and tailings beach slope, for example. Although the concept of a critical shear stress is a simple and convenient engineering metric, in practice the transition from solid to fluid-like behavior is much more complicated, resulting in a range of apparent yield stress values that vary with the applied shear conditions. For example, in constant rate or f..