SciELO - Scientific Electronic Library Online

vol.108 número3Computer simulation of air and methane flow following an outburst in transport gallery D-6, bed 409/4Prevention of chemical contamination of groundwater by mine water 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.108 no.3 Johannesburg Mar. 2008




A simple process control model for spiral concentrators



M.K.G. Vermaak; H.J. Visser; J.B. Bosman; G. Krebs

Department of Materials Science and Metallurgical Engineering, University of Pretoria, Pretoria, South Africa




Spiral concentration forms a crucial part of gravity separation circuits. The application of process models in the operation of gravity separation circuits offers significant benefits in recoveries and grade control. Significant strides in the modelling of spiral concentrators have been made during the last couple of decades. Despite these advances in modelling techniques and models, application in industrial processes is not fully optimized. The adjustment of splitter positions to accommodate changes in the feed parameters is impractical and difficult, resulting in losses. In this work an optical method is employed to detect the concentrate band position as a function of operating variables. As expected, the results indicate a strong influence of the solids content and total heavy mineral (THM) feed grade on the predicted gangue-mineral interface. Viscosity modifiers indicated the band position to be sensitive to viscosity and therefore the slimes content. Validation on an industrial sample indicated the possibility of using this model in feed-forward control application.



“Full text available only in PDF format”




1. HOLLAND-BATT, A.B. Spiral separation: theory and simulation, Transactions of the Institute of Mining and Metallurgy (Section C: Mineral Processing and Extractive Metallurgy), 1989, vol. 98, pp. C46-C60.         [ Links ]

2. HOLLAND-BATT, A.B. Interpretation of spiral and sluice tests, Transactions of the Institute of Mining and Metallurgy (Section C: Mineral Processing and Extractive Metallurgy), 1990, vol. 99, pp. C11-C20.         [ Links ]

3. LOVEDAY, G.K. and CILLIERS, J.J. Fluid flow modelling on spiral concentrators, Minerals Engineering, 1994, vol. 7, pp. 223-237.         [ Links ]

4. LI, M., JANCAR, T., HOLTHAM, P.N., DAVIS, J.J., and FLETCHER, C.A. Approaches to the development of coal spiral models, Kawatra, S.K. (ed.), High efficiency coal preparation: An International Symposium, Society of Mining, Metallurgy and Exploration, Littleton, Co., 1995, pp. 335-345.         [ Links ]

5. KAPUR, P.C. and MELOY, T.P. Spirals observed, International Journal of Mineral Processing, 1998,vol. 53, pp. 15-28.         [ Links ]

6. HOLLAND-BATT, A.B. and HOLTHAM, P.N. Particle and fluid motion on spiral separators, Minerals Engineering, 1991, vol. 4, pp 457-482.         [ Links ]

7. JOUBERT, D. Personal communications, 2007.         [ Links ]

8. KAWATRA, S.K., BAKSHI, A.K., and MILLER JR, T.E. Rheological characterization of mineral suspensions using vibrating sphere and a rotational viscometer, International Journal of Minerals Processing, 1996, vol. 44-45, pp. 155-165.         [ Links ]

9. ABELA, R. The effect of the slimes content on the rougher spiral circuit in a heavy mineral sands operation, SAIMM, Proceedings of the Heavy Mineral Conference 2003, 2003, pp. 1-8.         [ Links ]

10. BROWN, R. Slimes Effect on Spiral Efficiency, Report on the Cooljarloo North Mine, 2001.         [ Links ]

11. MORKEL, J. and VERMAAK, M.K.G. The role of swelling clay in kimberlite weathering, Mineral Processing and Extractive Metallurgy (Trans. Inst. Min. Metall. C), 2006, vol. 115, no. 3, pp. 150-154.         [ Links ]

12. STEINMULLER, A. Development and application of simple process models for spiral concentrators, SAIMM, 2005 Heavy Minerals Conference Proceedings, 2005, pp. 167-172.         [ Links ]



Paper received May 2007
Revised paper received Feb. 2008

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