Tailings particle size distribution methodology: the good, the bad, and the ugly

The determination of particle size distribution (PSD) is a critical aspect in the characterisation of mine tailings, influencing engineering assessments, particularly in the areas of thickening, rheology, transport and deposition. This paper critically evaluates various methodologies used to determine the PSD of tailings, with a focus on fractions smaller than two millimetres. The study highlights the variations in methodologies, particularly emphasising the inadequacies of traditional techniques originally developed for weathered soils, which are often inappropriately applied to freshly ground rock tailings. Through a comprehensive comparison, the paper identifies the strengths and limitations of each method, exposing outdated practices that may lead to inaccurate PSD results. The discussion culminates in a recommendation for the most suitable methodology for tailings PSD determination, considering the unique properties of tailings material. The findings aim to guide consultants and site-based personnel in selecting the most reliable and accurate techniques for tailings PSD analysis.