Ian Wark Research Institute
ARC Special Research Centre
ARC Special Research Centre
Research Area: Minerals and metallurgical processing, chemical engineering, physical chemistry
Supervisors:
A/Prof Daniel Fornasiero and
Dr Max Zanin
Description: The importance of the grinding and its environment
in flotation and recovering of fine particles, in particular fine
sulfide minerals, is evident. Research studies have revealed that by
controlling the grinding environment an optimum criterion for recovering
fine valuable minerals can be defined. Increasing fine particles
recovery and enhancing depression of gangue sulfide minerals can be
performed by grinding conditions. However, the importance of the
mechanism of size reduction in milling, eg, abrasion vs impact in
stirred media mill, on the floatability of different size fractions is
still unclear which is the main focus of the current proposed project.
Furthermore, the influence of breakage on fine particle oxidation and
hydrophobicity will be explored.
The project seeks to investigate the effect of impact and abrasion
mechanisms of size reduction in an Isa Mill by controlling the media
size relative to the feed particle size. Furthermore, surface analysis
techniques will be employed to explore the role of surface cleaning, ie,
removal of hydrophilic oxidized layers on flotation characteristics of
the fine value minerals. The oxidation state and hydrophobicity of the
ensuing fine particles generated in size reduction will be determined.
The project objectives are to enhance the surface cleaning action
relative to size reduction of stirred media mill (Isa Mill) and to
determine the effect of surface cleaning on the hydrophobicity and
flotation properties of the original particles and fine particles
produced from breakage. Furthermore, subsequent effects on
hydrophobicity, of fine particles generated in grinding will be
explored.
Expected outcomes: The outcomes will lead to establish a milling
strategy to produce unoxidised particles irrespective of the feed
surface condition
