The Use of Finite Element Modelling to Better Understand Electrostatic Separation

Electrostatic separation is a core requirement for the beneficiation of mineral sands suites to provide valuable product. Although the basis of electrostatic separation has been understood for some time, the details required to be able to calculate the metallurgical performance of a separator has not previously been achieved from a mechanistic perspective. Empirical models have had some success but require extensive test work. Traditionally, performance of an electrostatic separator is determined by careful experimental work using the target mineral suite. Although electrostatic separation was invented at the end of the 19th century, very little modification of the basic equipment occurred until relatively recently, with the addition of a plate electrode to aid separation. Previously, the author has presented results, calculated using finite element modelling (FEM), of the electric fields present in an electrostatic separator in various configurations. This paper will present some new mathematical modelling work, which uses the FEM determined electric field configurations but also incorporates some fundamental physical processes that provide insight as to the limitations and opportunities for this important separation technique.