SciELO - Scientific Electronic Library Online

vol.110 número11The efficiency of Wemco drums at Kleinkopje coal washing plant over 30 yearsThe potential of electrostatic separation in the upgrading of South African fine coal prior to utilization - a review índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados



Links relacionados

  • Em processo de indexaçãoCitado por Google
  • Em processo de indexaçãoSimilares em Google


Journal of the Southern African Institute of Mining and Metallurgy

versão On-line ISSN 2411-9717
versão impressa ISSN 0038-223X

J. S. Afr. Inst. Min. Metall. vol.110 no.11 Johannesburg Nov. 2010




Experiences in the production of metallurgical and chemical grade UG2 chromite concentrates from PGM tailings streams



N.F. Dawson

Xstrata, Rustenburg, South Africa




Recovery of a chromite concentrate from UG2 flotation tailings streams, of a grade suitable for further pyrometallurgical treatment for the production of ferrochrome, has certain specific challenges not only by virtue of the decoupled nature of the primary PGM recovery process and secondary gravity based chromite recovery circuits, but also because of intrinsic variations in the nature of the ore and its mineral composition. Variability in the ore, together with upstream process dynamics, creates a challenging environment in which to achieve optimal recovery of a gravity concentrate with accurate grade control. This paper examines certain interrelational aspects between the ore gangue and chromite mineral types, the influence of the primary PGM extraction circuit and secondary chromite extraction activity as applied specifically to UG2 ore against a background of actual plant experiences and circuit configurations applied in order achieve a suitable quality of chromite concentrate.

Keywords: UG2 chromite, spiral concentrators, chromite beneficiation



“Full text available only in PDF format”




1. DAAVITTILA, J., HONKANIEMI, M., and JOKINEN, P. The transformation of ferrochromium smelting technologies during the last decades. Tenth International Ferroalloys Congress, Cape Town, February 2004.         [ Links ]

2. CRAMER, L.A., BASSON, J., and NELSON, L.R. The impact of platinum production from UG2 ore on ferrochrome production in South Africa. Journal of the South African Institute of Mining and Metallurgy, pp. 517-527.         [ Links ]

3. Liddell, K. 25 Years of UG2 concentrators. Johannesburg, Mintek 75, 2009.         [ Links ]

4. NAIKER, O. and RILEY, T. Xstrata Alloys in Profile. Johannesburg: South African Institute of Mining and Metallurgy, South African Pyrometallurgy 2006, 5-8 March, 2006.         [ Links ]

5. ABELA, R. and DENYSSSSCHEN, D. Recovering gold from sand dumps using gravity concentration. Johannesburg, South African Institute of Mining and Metallurgy, July 2006.         [ Links ]

6. WALKLATE, J.R. and JERAM, H. The development of a metallurgical flowsheet to treat tails. The Journal of the South African Institute of Mining and Metallurgy. 2008, vol. 108.         [ Links ]

7. ABOLS, J.A. and GRADY, P.M. Maximizing Gravity Recovery through the application of multiple gravity Devices. Vancouver: Gekko Systems, 2006.         [ Links ]

8. KOHMUENCH, J.N. Improving Efficiencies in Water-Based Separators Using Mathematical Analysis Tools. Blacksberg, Virginia: Virginia Polytechnic and State University, December 2000.         [ Links ]

9. MATHEWS, B., FLETCHER, C.A.J., and PARTRIDGE, A.C. Computational Simulation of Fluid and Dilute Particle Flows on Spiral Concentrators. Perth, CSIRO, 1997. Inter conf on CFD&Metal Processing and Power Generation, CSIRO. pp. 101-108.         [ Links ]

10. RULE, C.M. and ANYIMADU, A.K. Flotation cell technology and circuit design- an Anglo Platinum perspective. Journal of The South African Institute of Mining and Metallurgy. 2007, vol. 107.         [ Links ]

11. RULE, C.M. Energy considerations in the current PGM processing flowsheet utilizing new technologies. The Journal of The South African Institute of Mining and Metallurgy. 2009, vol. 108.         [ Links ]

12. LIDDELL, K.S., MCRAE, L.B., and DUNNE, R.C. Process routes for beneficiation of noble metals from Merensky and UG-2 ores. Mintek Review. no. 4, 1986.         [ Links ]

13. PINCOCK, ALLEN AND HOLT. The Processing of Platinum Group Metals (PGM)- Part 1. Pincock Perspectives. March, 2008.         [ Links ]

14. CAWTHORN, R.G. The platinum and Palladium resources of the Bushveld Complex. Journal of Science. November/December, 1999, vol. 95.         [ Links ]

15. HESS, H.H. Orthopyroxenes of the Bushveld type, ion substitutions and changes in unit cell dimensions. Princeton New Jersey: Princeton University, 1944.         [ Links ]

16. MAIER, W.D. Olivine oikocrysts in Bushveld Anorthosite: some implications for cumulate formation. The Canadian Mineralogist. 1995, vol. 33, pp. 1011-1022.         [ Links ]

17. SEKIN, T. Liquidus temperature of plagioclase and pyroxene in andesitic melts at one atmosphere. Geochemical Journal. 1986, vol. 20, pp. 287-296.         [ Links ]

18. ZACCARINI, F., GARUTI, G., and CAWTHORN, R.G. Platinum-Group Minerals in chromite Xenoliths from the Onverwacht and Tweefontein ultramafic Pipes, Eastern bushveld complex, South Africa. The Canadian Mineralogist. 2002, vol. 40, pp. 481-497.         [ Links ]

19. SIAME, J. Physical beneficiation of PGM tailings by Gravity Separation and Elutriation Techniques. MSc thesis. Tswane, Tswane University of Technology, January 2008.         [ Links ]

20. HOLLAND-BLATT, A.B. and HOLTHAM, P.N. Particle and fluid motion on spiral concentrators. Mineral Engineering. 1991, vol. 4, no. 3/4.         [ Links ]

21. PRINSLOO, T.R. and ABELA, R.L. Multiple Stage Fine coal Spiral Concentrators. Brisbane, Proceedings of the International Coal Preparation Congress, 1998.         [ Links ]

22. VERMAAK, M.K.G., VISSER, H.J., BOSMAN, J.B., AND KREBS, G. S.L. A simple process control model for spiral concentrators The Journal of the South African Institute of Mining and Metallurgy, 2008, vol. 108.         [ Links ]

23. MOHANTY, M.K. Final technical report: Automation and performance improvement of spiral concentrators. Southern Illinois University: ICCI, 2007.         [ Links ]

24. BARNES, A.R., FINN, C.W.P., and ALGIE, S.H. The prereduction and smelting of chromite concentrate of low chromium-to-iron ratio. Johannesburg, Journal of the South African Institute of Mining and Metallurgy, March 1983.         [ Links ]

25. ROACH, T.A. and ROEDER, P.L. Composition of chromite in the upper chromite, Muskox layered intrusion, Northwest Territories. The canadian Mineralogist. 1998, Vol. 36, pp117-135.         [ Links ]

26. IHC Jig versus other gravity separators-reprinted from Ports and Dredging. IHC Holland. Sliedrecht, Holland: Ports and Dredging, 1991, vol. 128.         [ Links ]

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons