The Possibility of Flotation and Gravity Separation Methods for a Mixed Pb and Zn Oxide-Sulfide Ore

Document Type : Research Paper

Authors

1 Arak University of Technology, Arak, Iran

2 Iranian Research Organization for Science and Technology, Tehran, Iran. Postal code: 3313193685

3 Miduk Copper Complex, National Iranian Copper Industry Company, Kerman, Iran.

Abstract

With the depletion of lead and Zn sulphide reserves, processing of oxide and oxide-sulphide mixture deposits has gained significant importance. In the present research, lead and zinc minerals were concentrated from an oxide-sulphide ore containing 2.92% Zn (2.42% oxide) and 1.61% lead (1.23% oxide) with silicate gangue. Flotation experiments were conducted with two approaches: differential flotation of sulphide and oxide minerals in several stages, and cumulative flotation of mixed sulphide-oxide minerals. The effects of desliming and flotation reagents were examined. Results indicated that differential flotation of sulphide and oxide minerals is impractical for this ore. Optimal conditions for ore concentration were identified as flotation of mixed sulphide-oxide minerals of lead with d80 of 90 μm and the addition of 6000 g/t sodium sulphide in the rougher stage and 1000 g/t in the scavenger stage. Bromoform heavy liquid tests revealed that Zn recovery in the heavy fraction remained relatively unchanged with particle size reduction, whereas Pb recovery increased from 74.22% to 89.09%. Finally, a combination of mixed sulphide-oxide flotation along with gravity separation using a shaking table and spirals was proposed.

Keywords