JOURNAL PAPER

Assessing the effects of the cone force ratio on the performance of hydrocyclones

D. Lusinga; J. Angombe; A.N. Mainza

Centre for Minerals Research, University of Cape Town, Rondebosch, South Africa

SYNOPSIS

Hydrocyclones are a common feature in almost all mining operations in the world, serving mainly as classifiers. Some of their advantages include low capital costs, low space requirements and their ability to reduce residence time in closed circuit grinding processes. Although an extensive body of literature exists for hydrocyclones, these devices are still inherently inefficient, and more research is currently being undertaken, particularly in the field of modelling. In the vast body of hydrocyclone literature published so far, there has been little or no effort devoted to analysing the effect of the cone force ratio on the performance of ydrocyclones. The cone force ratio is defined as the ratio of the spigot to the vortex finder diameter (Shah, 2005).
In this study a total of 44 tests was carried out in a custom-built rig at the University of Cape Town. These tests were aimed at evaluating the effect of the cone force ratio on the performance of a small diameter hydrocyclone. The cut size and water split were used as the criterion for evaluating the performance of the ydrocyclone.
Results from the tests showed that the cut size decreased with an increase in the cone force ratio. The cut size also appeared to decrease as the calculated locus of zero vertical velocity (LZVV) shifted inwards. The water recovery to the underflow appeared to increase with an increase in the cone force ratio. The effect on the cut size of adjusting the cone force ratio was found to be higher for a coarser feed than it was for a finer feed.

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References

ASOMAH, I. Thesis: Improved Models of Hydrocyclones Julius Kruttschnitt Mineral Research Centre, University of Queensland Australia, 1966.         [ Links ]

BRADLEY, D. The hydrocyclone, 1st edition., Pergamon Press, Oxford.         [ Links ]

DE KOK, S.K. J Chem. Met & Min Soc., South Africa, vol. 56, no. 281, 1965. pp. 1956.         [ Links ]

FUJIMOTO, T. The performance of the Hydrocyclone as a classifier, retrieved September 20, 2008 from the World Wide Web: http://www.journalarchive.jst.go.jp/jnlpdf.php?cdjournal=jsme1958&cdvol=1&noissue=3&startpage=321&lang=en&from=jnlabstract. 1958.         [ Links ]

HAAS, P.A. Chem Engng.Progr., vol. 53, no. 203, 1957.         [ Links ]

KELLSALL, D.F. A study of the motion of solid particles in a hydraulic cyclone, retrieved September 29, 2008 from the World Wide Web:http://archive.icheme.org/cgibin/somsid.cgi?session=711809B&page=30ap0087&type=framedpdf. 1952 .         [ Links ]

LIM,K.S., KIM, H.S., and LEE, K.W. Characteristics of the collection efficiency for a cyclone with different vortex finder shapes, retrieved September 20, 2008 from the World Wide Web: http://www.sciencedirect.com, 2003.         [ Links ]

MODER,S.J. and DAHLSTROM, D.A. Chem.Engng.Progr., vol. 48, no. 75, 1952.         [ Links ]

NAPIER-MUNN, T.J., MURELL, S., MORRISON, R.D., and KOJOVIC, T. Mineral Communtion circuits-Their Operation and Optimisation. JKMRC Monograph Series in Mineral Processing 2.JKMRC, University of Queenslad, Australia, 1996.         [ Links ]

NEESSE, T., and DUECK, J. Dynamic modelling of the hydrocyclone, retrieved September 24, 2008 from the World Wide Web: http://www.sciencedirect.com , 2006.         [ Links ]

SHAH, H., MAJUMDER, A.K., and BARNWAL, J.P. Development of water split model for a 76 mm hydrocyclone, 2005.         [ Links ]

SVAROVSKY, L. Solid-Liquid Separation, 4th edition, Butterworths, London, 2000.         [ Links ]

Paper written on project work carried out in partial fulfilment of B.Sc. (Chem. Eng.)