TRANSACTION PAPER

Recovery of base metals and PGMs in a DC alloy-smelting furnace

R.T. Jones; I.J. Geldenhuys; Q.G. Reynolds

Pyrometallurgy Division, Mintek, Randburg, South Africa

SYNOPSIS

Base metals and platinum group metals can be collected in metallic alloy form, via a wide variety of smelting processes. The recovery, or degree of collection, of the valuable metals is a function of the extent of reduction in the furnace, which, in turn, is indicated by the fraction of iron present in the feed materials that report to the alloy. An equation has been developed that relates the recovery of various metals (such as Ni, Co, Cr, and PGMs) to the recovery of Fe. This recovery equation (for each metal) is characterized by a single parameter (K_y) that can either be empirically fitted to the data, or expressed in terms of the equilibrium constant and the ratios of the activity coefficients involved. Data from a number of varied DC arc furnace campaigns are presented to illustrate this behavior.

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References

1. JONES, R.T. and CURR, T.R. Pyrometallurgy at Mintek, Southern African Pyrometallurgy 2006, R.T. Jones (ed.) SAIMM, Johannesburg, 5-8 March 2006, pp. 127-150. http://www.mintek.co.za/Pyromet/Files/2006JonesMintek.pdf        [ Links ]

2. Jones, R.T., Denton, G.M., Reynolds, Q.G., Parker, J.A.L., and van Tonder, G.J.J. Recovery of cobalt from slag in a DC arc furnace at Chambishi, Zambia, SAIMM Journal, vol. 102, no. 1, January/February 2002, pp. 5-9. http://www.mintek.co.za/Pyromet/Files/Chambishi.pdf        [ Links ]

3. HOLZHEID, A., PALME, H., and CHAKRABORTY, S. The activities of NiO, CoO and FeO in silicate melts, Chemical Geology, vol. 139, 1997, pp. 21-38.         [ Links ]

4. HOLZHEID,A. and PALME, H. The influence of FeO on the solubilities of cobalt and nickel in silicate melts, Geochimica et Cosmochimica Acta, vol. 60, no. 7, 1996, pp. 1181-1193.         [ Links ]

5. TEAGUE, K.C., SWINBOURNE, D.R., and JAHANSHAHI, S. Activity coefficient of cobalt oxide in non-ferrous smelting slags-a review, Proceedings Australian Institute of Mining and Metallurgy, no. 1, 1998, pp. 1-6.         [ Links ]

6. TEAGUE, K.C., SWINBOURNE, D.R., and JAHANSHAHI, S. Thermodynamics of cobalt oxide in iron silicate-based slags, The AusIMM Proceedings, no. 1, 2000, pp. 66-72.         [ Links ]

7. GELDENHUYS, I.J. AND LAGENDIJK, H. A twin-cathode DC arc smelting test at Mintek to demonstrate the feasibility of smelting FeNi from calcine prepared from siliceous laterite ores from Kazakhstan for Oriel Resources plc, International Ferroalloys Conference, Infacon XI, New Delhi, India, 18-21 February 2007, pp.781-797. http://www.mintek.co.za/Pyromet/Files/2007Reinecke.pdf        [ Links ]

8. JONES, R.T. ConRoast: DC arc smelting of dead-roasted sulphide concentrates, Sulfide Smelting 2002, R.L. Stephens and H.Y. Sohn (eds.). TMS (The Minerals, Metals & Materials Society), Seattle, 17-21 February 2002, pp.435-456. http://www.mintek.co.za/Pyromet/Files/ConRoast.pdf        [ Links ]

9. JONES, R.T. and KOTZÉ, I.J. DC arc smelting of difficult PGM-containing feed materials, International Platinum Conference, 'Platinum Adding Value', The South African Institute of Mining and Metallurgy, Sun City, South Africa, 3-7 October 2004, pp.33-36. http://www.mintek.co.za/Pyromet/Files/2004JonesConSmelt.pdf        [ Links ]

10. GELDENHUYS, I.J. and JONES, R.T. Four years of DC arc smelting of PGMcontaining oxide feed materials at Mintek, Pyrometallurgy of Nickel and Cobalt 2009, 48th Annual Conference of Metallurgists of CIM, Sudbury, Ontario, Canada, 23-26 August 2009, pp.415-427. http://www.mintek.co.za/Pyromet/Files/2009Geldenhuys.pdf        [ Links ]

11. MCCULLOUGH, S.D., GELDENHUYS, I.J., and JONES, R.T. Pyrometallurgical iron removal from PGM-containing alloys, Third International Platinum Conference, Platinum in Transformation, The Southern African Institute of Mining and Metallurgy, Sun City, 5-9 October 2008, pp.169-176. http://www.mintek.co.za/Pyromet/Files/2008McCullough1.pdf        [ Links ]