PhD Project title The influence of phyllosilicate mineralogy on the rheology of mineral slurries
(Supervisors: Prof DA Deglon, Dr M Becker, Prof J-P Franzidis) Graduated: 2011
In the past, the processing of phyllosilicate mineral bearing ores has been problematic with difficulties such as reduced flotation rates and complex tailings treatment arising. This study set out to develop a better understanding of the rheological behaviour of phyllosilicate minerals may provide insight into special measures that will be required during the beneficiation of the ores. This project focuses on the analysis of three phyllosilicate minerals which commonly exist as major gangue components in many industrial ores: chrysotile with its fibrous nature, phlogopite with its thin platy structure and vermiculite which exhibits concertina-like swelling behaviour. In this study, the rheological behaviour of the individual phyllosilicate minerals was investigated. Zeta potential and RM–titration measurements as a function of pH were used to infer the surface charge characteristics of each of the minerals. This was extended to an analysis of the influence of the minerals on the rheological properties of suspensions containing mixtures of quartz and each phyllosilicate mineral in turn, which serve as a preliminary simulation of a real ore system. The results from this were compared to the rheological characteristics of a real ore containing one or two of the studied phyllosilicate minerals.
Peer-reviewed journal publications
Becker, M.E., Yorath, G.A., Ndlovu, B., Harris, M.C., Deglon, D.A. and Franzidis, J.-P. 2013. A rheological investigation of the behaviour of two Southern African platinum ores. Minerals Engineering, 49: 92-97.
Ndlovu, B., Forbes, E., Becker, M.E., Deglon, D.A., Franzidis, J.-P. and Laskowski, J.S. 2011. The effects of chrysotile mineralogical properties on the rheology of chrysotile suspensions. Minerals Engineering, 24: 10041009.
Ndlovu, B., Becker, M.E., Forbes, E., Deglon, D.A. and Franzidis, J.-P. 2011. The influence of phyllosilicate mineralogy on the rheology of mineral slurries. Minerals Engineering, 24: 1314-1322.
Peer-reviewed conference proceedings
Ndlovu, B.N., Burdukova, E., Becker, M., Deglon, D.A., Franzidis, J.-P.and Laskowski, J.S. 2010. An investigation on the effects of chrysotile particle shape and anisotropic properties on the rheology of chrysotile suspensions, XXV International Mineral Processing Congress (IMPC), Brisbane, Australia, 5-10 September, 2010
Oral conference presentations
Ndlovu, B., Kilickaplan, I. and Laskowski, J.S. 2010. The rheology of aqueous suspensions of needle-like mineral particles, presented at the UBC-McGill-UA International Symposium, Vancouver 6-10 October, 2010
Ndlovu, B., Becker, M., Deglon, D.A. and Burdukova, L. 2010. The influence of phyllosilicate mineralogy on the rheology of mineral slurries. Process Mineralogy 2010, Cape Town, 10-12 November 2010.