Use of centrifugal-gravity concentration for rejection of talc and recovery improvement in base-metal flotation

Klein B., ALTUN N. E., Ghaffari H.

INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS, vol.23, no.8, pp.859-867, 2016 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 23 Issue: 8
  • Publication Date: 2016
  • Doi Number: 10.1007/s12613-016-1301-5
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.859-867
  • Keywords: flotation, base metals, talc, centrifugation, gravity concentrators, KNELSON CONCENTRATOR, FINE COAL, SEPARATION, PERFORMANCE, BEHAVIOR
  • Middle East Technical University Affiliated: Yes


The possibility of using a centrifugal-gravity concentrator to reject Mg-bearing minerals and minimize metal losses in the flotation of base metals was evaluated. Sample characterization, batch scoping tests, pilot-scale tests, and regrind-flotation tests were conducted on a Ni flotation tailings stream. Batch tests revealed that the Mg grade decreased dramatically in the concentrate products. Pilot-scale testing of a continuous centrifugal concentrator (Knelson CVD6) on the flotation tailings revealed that a concentrate with a low mass yield, low Mg content, and high Ni upgrade ratio could be achieved. Under optimum conditions, a concentrate at 6.7% mass yield was obtained with 0.85% Ni grade at 12.9% Ni recovery and with a low Mg distribution (1.7%). Size partition curves demonstrated that the CVD also operated as a size classifier, enhancing the rejection of talc fines. Overall, the CVD was capable of rejecting Mg-bearing minerals. Moreover, an opportunity exists for the novel use of centrifugal-gravity concentration for scavenging flotation tailings and/or after comminution to minimize amount of Mg-bearing minerals reporting to flotation.