Effect of Galvanic Interaction Between Grinding Media and Sulfide Minerals on Grinding and Flotation Efficiency

Document Type : Research - Paper

Authors

1 Associate Professor, Dept. of Mining Engineering, University of Birjand, Birjand, Iran

2 M.Sc, Dept. of Mining Engineering, University of Birjand, Birjand, Iran

Abstract

Galvanic interaction between sulphide minerals and grinding media has a pronounced impact on grinding (in terms of wear rate of balls and liners, energy consumption, product size and throughput) and flotation (in terms of surface products formed which affect mineral hydrophobicity) performance. The main objective of the current research study is to investigate the influence of electrochemical control on grinding and flotation performance. Laboratory tests were carried out on a representative sample taken from the Miduk copper concentrator plant feed under controlled electrochemical conditions. Laboratory grinding tests with different grinding media indicated that chromium balls not only resulted in the reduced grinding media wear in the mill, but also led to the improved flotation performance.The mass wear rate of steel balls was found to be 1.68 times of high-chromium balls. This is related to more oxidizing and alkaline conditions with higher oxygen concentrations in the presence of high-chromium balls. Addition of lime in the mill caused more oxidizing conditions (increasing the pulp Eh from 55.91 mV to 189.79 mV) with higher oxygen content (increasing the pulp DO from 2.44 ppm to 6.39 ppm) of the pulp which eventually resulted in higher flotation grade and recovery. Maximum copper recovery was observed when xanthate (Z11) and thionocarbamate (X231) collectors were added to the flotation cell, while the highest selectivity was achieved when the both collectors were fed directly into the mill. The more reducing grinding conditions and lower oxygen content of the pulp was related to oxidation of xanthate to dixanthogen when it was added into the mill.

Keywords

References

  1. Wills, B. A., and Napier-Munn, T. J. (2006). “Mineral processing technology”. Elsevier Science & Technology Books.
  2. Rabieh, A., Albijanic, B., and Eksteen, J. J. (2016). “A review of the effects of grinding media and chemical conditions on the flotation of pyrite in refractory gold operations”. Minerals Engineering, 94: 21-28.
  3. Aldrich, C. (2013). “Consumption of steel grinding media in mills-a review”. Minerals Engineering, 49: 77-91.
  4. Greet, C. J., Small, G. L., Steinier, P., and Grano, S. R. (2004). “The Magotteaux Mill investigating the effect of grinding media on pulp chemistry and flotation performance”. Minerals Engineering, 17: 891-896.
  5. Fontana, M. G. (1987). “Corrosion engineering”. Third ed. McGraw-Hill International Edition, New York.
  6. Bruckard, W. J., Sparrow, G. J., and Woodcock, J. T. (2011). “A review of the effects of thegrinding environment on the flotation of copper sulfides”. International Journalof Mineral Processing, 100(1-2): 1-13.
  7. Simmons, G. L., Orlich, J. N., Lenz, J. C., and Cole, J. A. (1999). “Implementation and start-up of N2TEC flotation at the Lone Tree mine”. In: Parekh, B. K., Miller, J. D. (Eds.), Advances in Flotation Technology. Society of Mining Enginers, Littleton, 183-195.
  8. Rao, S. R. (2004). “Surface chemistry of froth flotation”. Plenum Press, New York.
  9. Leppinen, J. O., Kalapudas, R., and Heiskanen, K. (2000). “Influence of grinding media on the electrochemistry of sulphide ore flotation”. In: Electrochemistry in Mineral and Metal Processing,Woods, R., and Doyle, F. M. (Eds.), Electrochem. Soc, Pennington, USA, 1-12.
  10. Azizi, A., Shafaei, S. Z., Noaparast, M., and Karamoozian, M. (2015). “An investigation of the corrosive wear of steel balls in grinding of sulphide ores”. International Journal of Mining and Geo-Engineering, 49(1): 83-91.
  11. Azizi, A., Shafaei, S. Z., Noaparast, M., and Karamoozian, M. (2013). “The effect of pH, solid content, water chemistry and ore mineralogy on the galvanic interactions between chalcopyrite and pyrite and steel balls”. Frontiers of Chemical Science and Engineering, 7(4): 464-471.
  12. Peng, Y., and Grano, S. (2010). “Effect of grinding media on the activation of pyrite flotation”. Minerals Engineering, 23: 600-605.
  13. Zanina, M., Lambert, H., and du Plessis, C. A. (2019). “Lime use and functionality in sulphide mineral flotation: A review”. Minerals Engineering, 143: 105922.
  14. Multani, R. S., Williams, H., Johnson, B., Li, R., and Waters, K. E. (2018). “The effect of superstructure on the zeta potential, xanthate adsorption, and flotation response of pyrrhotite”. Colloidsand Surfaces A: Physicochemical and Engineering Aspects, 551: 108-116.
  15. Yelloji Rao, M. K., and Natarajan, K. A. (1991). “Factors influencing ball wear and flotation with respect to ore grinding”. Mineral Processing and Extractive Metallurgy Review, 7: 137-173.

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History

  • Receive Date: 06 October 2020
  • Revise Date: 13 January 2021
  • Accept Date: 13 January 2021

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