Ian Wark Research Institute
ARC Special Research Centre
ARC Special Research Centre
Research Area: Chemical engineering, mineral processing, physical chemistry
Supervisor: Dr Max Zanin
Description: Froth flotation is widely used in mineral processing
industry. Froth flotation utilises differences in physicochemical
surface properties of various minerals to achieve specific separation.
Hydrophobic particles attach to air bubbles and are transported upwards
into a froth layer at the top of the flotation cell, while hydrophilic
particles remain in the slurry in the flotation cell forming the tail.
Frothers are added to stabilise bubble formation in the pulp phase to
create a stable froth while allowing selective drainage of entrained
gangue, and to increase flotation kinetics. Froth structure and froth
stability are known to play a significant role in determining the
mineral grade and recovery achieved from a flotation operation. Froth
stability is mainly depending on frother (type and concentration) and
amount and nature of the suspended particles, in particular particle
hydrophobicity and size. However, there are other parameters such as
quality of water which is not yet fully understood. In mineral
flotation, the recycling of process water to reduce freshwater
consumption is increasingly being common. However, using recycled water
normally leads to the build-up of salts and surfactants in the process
water. Therefore, the effect of the process water chemistry on plants,
product quality and separation is very important.
The project objective will be to investigate the effect of water
quality, including pH and type and concentration of salts (such as
CaCl2, MgCl2 and NaCl) on froth stability, as well as valuable mineral
recovery in froth flotation of a sulphide ore.
Expected outcomes: To determine the effect of water quality (pH
and salt type and concentration) on froth stability and mineral
flotation recovery.
