Quantifying a black art: The electrostatic separation of mineral sands

Abstract Mathematical models of high tension roll (HTR) and electrostatic plate (ESP) separators have been developed during recent research conducted into the Australian mineral sands industry. All machine, mineral and atmospheric variables have been incorporated into model structures which predict the performance of a single stage of separation. Multiple stage machines or dry plant circuits are simulated as a series of single stages. Each feed mineral is assigned a distribution of properties described by a mean charge relaxation time and a surface variance term. The separation of each mineral is then predicted from the interaction of these characteristics and the machine operating conditions. Model output is a complete description of all product streams. These models accurately predict full-scale separator performance under a wide range of operating conditions. A number of conclusions regarding the operation of electrostatic separators have emerged from the findings of this study. A commercial software package for mineral sands simulation — JKSimSand — is currently being used at the JKMRC to test the application of these models.