Mineral Processing Research Group (MPRG)
We often find that the comminution section of a mineral processing plant accounts for half the cost of running the plant and flotation consumes large amounts of water, which cannot go un-noticed in an increasingly arid country such as ours. Other unit operations such as magnetic separation, specific gravity separation, etc also contribute to the costs incurred in providing vast tonnages of refined ore to downstream plants (such as hydro- and pyro-metallurgy) which extract the metals, fertilisers and fuels that build a productive South Africa.
Purpose and Mission
Our focus is on the processes that take the coarse material produced by the mine, crush and mill them to appropriate sizes and separate by physical means the valuable particles from the low-grade particles. Production of these is our mission. The valuable particles are then processed further downstream to extract the valuable materials from them (the mission of other Research Groups in our School) while the latter are stored in tailings dams or waste dumps.
Research Focus Areas
- Comminution which includes crushing, screening, milling and classification. The aim of these processes is to liberate the valuable particles in the coarse ore made available by the mine.
- Flotation which involves using an appropriate chemical environment to render selected valuable particles hydrophobic while leaving the rest of the particles hydrophilic. The latter may contain more valuable minerals that can be floated after an appropriate change in the chemical regime (eg by manipulation of the pH of the slurry).
- Jigging which involves the use of a pulsing mechanism to separate particles based on their density. For example coal can be upgraded by using jigging to separate the rocky component of the coal from the organic component.
Postgraduate Training
Graduates from our School or from other universities worldwide who have performed well in their undergraduate courses are welcome to join our group and improve their qualifications through various routes to higher degrees at master's and PhD level.
Current Staff and Students in our Group
- Associate Professor Mulenga Bwalya - expert in comminution modelling and simulation
- Prof Michael Moys focusing on flotation and comminution
- Prof L Woollacott - opening up new approaches to jigging
- Mr Kitungwa (Martin) Kabezya doing a PhD in comminution
- Mr Eric Tshibwabwa measuring bubble size in flotation froths