Due to progressive depletion of high-grade deposits, the dry beneficiation of calcium carbonate raw material by triboelectric means is becoming increasingly attractive. The present paper gives a review of the main aspects of tribocharging and the subsequent behaviour of the charged particles in the electric field of a free-fall separator. Particular emphasis is devoted to the extent of influence of material properties and equipment characteristics on electrostatic separation. The investigation aimed at evaluating the optimum design criteria for the development of a commercial electrostatic separator to successfully remove siliceous and colouring constituents from calcium carbonate. Therefore, a pilot-scale electrostatic separation system with a nominal capacity of 2.7t/h was developed. The experimental procedure and the instrumentation used in the study are described in detail. Under proper conditions, mineral particles acquire selectively electrical charges and can be separated when passed through the separator. The experimental data exhibit that the best separation results are obtained when the mineral sample is heated and processed in dry atmosphere. Other parameters that strongly influence the efficiency of separation are splitter position, feed rate, fineness of the feed material, and temperature and/or material of the tribocharger. The prospects for the industrial application of triboelectric separation in dry processing of calcium carbonate are fruitful.
|Translated title of the contribution||Untersuchungen zur Optimierung der Prozessbedingungen bei der triboelektrostatischen Sortierung von Industriemineralen|
|Award date||30 Mar 2007|
|Publication status||Published - 2007|
Bibliographical noteembargoed until null
- Electrostatic separation Tribocharging Free-fall separator Material properties Equipment characteristics Calcium carbonate