Electrokinetic dewatering of mine tailing : infuence of solid content and voltage level applied.

Abstract

The process of disposing the tailings from mining activities generally involves the construction of large storage structures, either because of the large volume of residue generated by industrial processing plants or the difculties in obtaining grants for new disposal areas. Over the past few years, such storage structures have been maximized to astonishing dimensions, considerably increasing the risk associated with possible rupture. Therefore, new management techniques, such as the integration of several mining areas involved in the exploration, and processing and residue disposal, need to be developed for reducing the generated residue volume and for optimizing the disposal processes of such materials. One of the residue disposal methodologies currently under study is the acceleration of the dewatering/consolidation process of the so-called fne residues, using electrokinetic techniques. In this context, this study conducts electrokinetic dewatering tests on fne bauxite tailing, using samples with initial solid content by weight ranging from 20 to 30%; fnal values between 43 and 66% are achieved. The estimated power consumption per volume of drained water ranges from 31.4 to 375.2 kWh/m3 . The obtained results establish that the utilization of electrokinetic processes in the dewatering of tailings is a technique worthy of further investigation.