MLA-based partition curves for magnetic separation

Mineral liberation analysis (MLA) allows access to detailed information on the composition of a sample as well as of single particles visible on the cross-sectioned surface of a grain mount. This information can be used to evaluate processing related to the liberation distribution of valuables or to the distribution of a feature used for separation of valuables from barren particles. When separation processes are studied, the separation feature has to be added to the particle population data. In case of density separation (particle size and particle density) this is already been done by MLA software. For magnetic separation the MLA data has to be combined with mineral susceptibilities using additional software.
This article describes the calculation of partition curves for magnetic separation based on the liberation analysis of the feed and the products. Magnetic susceptibility data from measurements of pure minerals and from literature are is and combined with the particle composition data from the liberation analysis. Using sieved fractions in the magnetic separation experiments the evolution of cut susceptibility and separation efficiency with particle size is studied. The effects of a stereological correction and of the width of susceptibility classes as well as of the mineral susceptibilities used in calculation are discussed.