Combined Benedetti-Pichler/Stange–Poole sampling equation for two-component particulate mixtures

Abstract

General equations for the estimation of statistical uncertainty in the sampling of mixtures of two types of particles were developed that take into account variability in particle size and composition. Different expressions were obtained for situations where the component of interest is present in bulk or trace amounts. The general equation for a bulk component was verified experimentally by sampling KCl–NaCl and KCl–sucrose mixtures with various particle sizes and compositions with a spinning riffler and determining the relative standard deviation of the percentage of Cl or KCl under conditions where the analytical uncertainty was small.