Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-22T19:45:10.630Z Has data issue: false hasContentIssue false

Primary and secondary phases in copper-cobalt smelting slags from the Copperbelt Province, Zambia

Published online by Cambridge University Press:  05 July 2018

M. Vítková*
Affiliation:
Institute of Geochemistry, Mineralogy and Mineral Resources, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Prague 2, Czech Republic
V. Ettler
Affiliation:
Institute of Geochemistry, Mineralogy and Mineral Resources, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Prague 2, Czech Republic
Z. Johan
Affiliation:
Bureau des Recherches Géologiques et Minières (BRGM), av. Claude Guillemin, 45060 Orléans, cedex 2, France
B. Kříbek
Affiliation:
Czech Geological Survey, Geologická 6, 152 00 Prague 5, Czech Republic
O. Šebek
Affiliation:
Laboratories of the Geological Institutes, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Prague 2, Czech Republic
M. Mihaljevič
Affiliation:
Institute of Geochemistry, Mineralogy and Mineral Resources, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Prague 2, Czech Republic
*

Abstract

Pyrometallurgical slags from three Cu-Co smelters (Nkana, Mufulira, Chambishi) in the Copperbelt Province, Zambia, were studied from mineralogical and chemical points of view. The slags were enriched in metals and metalloids, mainly Cu (up to 35 wt.%), Co (up to 2.4 wt.%) and As (up to 3650 ppm). The following primary phases were observed in slags: Ca-Fe silicates (clinopyroxene, olivine) and leucite, oxides (spinel-series phases), ubiquitous silicate glass and sulphide/metallic droplets of various sizes. The presence of glass and skeletal/dendritic crystal shapes indicated rapid cooling of the slag melt. Copper and cobalt were found in low concentrations in the majority of silicates (olivine, clinopyroxene) and oxides, substituting for Fe in their structures (up to 7.15 wt.% CoO in olivine, 4.11 wt.% CuO in spinel). Similarly, up to 0.91 wt.% CoO and 6.90 wt.% CuO were observed in the interstitial glass. Nevertheless, the main carriers of these metals in the slags studied were Cu sulphides (digenite, chalcocite, bornite, chalcopyrite), Co-Fe sulphides (cobaltpentlandite), Co-bearing intermetallic phases ((Fe,Co)2As) and alloys. Weathering features corresponding to the presence of secondary metal-bearing phases, such as malachite (Cu2(CO3)(OH)2), brochantite (Cu4SO4(OH)6) and sphaerocobaltite (CoCO3), were observed on the slag surfaces. They indicate that the slags studied are reactive on contact with water/atmosphere and that their environmental stability and release of potentially harmful metals and metalloids must be evaluated further.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Annels, A.E. (1984) The geotectonic environment of Zambian copper-cobalt mineralization. Journal of the Geological Society of London, 141, 279289.CrossRefGoogle Scholar
Berger, E., Frot, G., Lehmann, J., Marion, C. and Vannier, M. (1982) A very sensitive potential geothermometer based on spinel silica content of olivine-rocks. Comptes Rendus de I'Académie des Sciences, Paris, série II, 294, 733736.Google Scholar
Bril, H., Zainoun, K., Puziewicz, J., Courtin-Nomade, A., Vanaecker, M. and Bollinger, J.C. (2008) Secondary phases from the alteration of a pile of zinc-smelting slags as indicators of environmental conditions: an example from Świętochłowice, Upper Silesia, Poland. The Canadian Mineralogist, 46, 12351248.CrossRefGoogle Scholar
Cabri, L.J. (1973) New data on phase relations in the Cu-Fe-S system. Economic Geology, 68, 443454.CrossRefGoogle Scholar
Cutler, C.J., Natarajan, M., Mponda, E. and Eksteen, J.J. (2006) Phasing out reverbatory furnace operations at KCM Nkana. In: Southern African Pyrometallurgy 2006 (Jones, R.T., editor). South African Institute of Mining and Metallurgy, Johannesburg, March 5—8, 2006, pp. 251264.Google Scholar
Czamanske, G.K., Himmelberg, G.R. and Goff, F.E. (1976) Zoned Cr, Fe-spinel from the La Perouse layered gabbro, Fairweather Range, Alaska. Earth and Planetary Science Letters, 33, 111118.CrossRefGoogle Scholar
Davenport, W.G., King, M., Schlesinger, M. and Biswas, A.K. (2002) Extractive Metallurgy of Copper, 4th edition. Pergamon Press, Oxford, UK, 452 pp.Google Scholar
Ettler, V. (2002) Etude du potentiel polluant de rejets anciens et actuels de la métallurgie du plomb dans le district de Příbram (République Tchèque). Document du BRGM 301, ISBN 2-7159-0924-01 Orleans, France, 266 pp.Google Scholar
Ettler, V., Legendre, O., Bodénan, F. and Touray, J.C. (2001) Primary phases and natural weathering of old lead-zinc pyrometallurgical slag from Příbram, Czech Republic. The Canadian Mineralogist, 39, 873888.CrossRefGoogle Scholar
Ettler, V., Piantone, P. and Touray, J.C. (2003a) Mineralogical control on inorganic contaminant mobility in leachate from lead-zinc metallurgical slag: experimental results and long-term assessment. Mineralogical Magazine, 67, 12691283.CrossRefGoogle Scholar
Ettler, V., Johan, Z. and Hradil, D. (2003b) Natural alteration products of sulphide mattes from primary lead smelting. Comptes Rendus Geoscience, 335, 10131020.CrossRefGoogle Scholar
Ettler, V., Johan, Z., Kříbek, B., Šebek, O. and Mihaljevič, M. (2009a) Mineralogy and environmental stability of slags from the Tsumeb smelter, Namibia. Applied Geochemistry, 24, 115.CrossRefGoogle Scholar
Ettler, V., Červinka, R. and Johan, Z. (2009b) Mineralogy of medieval slags from lead and silver smelting (Bohutín, Příbram district, Czech Republic): Towards estimation of historical smelting conditions. Archaeometry, 51, 9871007.CrossRefGoogle Scholar
Fleet, M.E. (2006) Phase equilibria at high temperatures. Pp. 365419 in: Sulfide Mineralogy and Geochemistry (Vaughan, D.J., editor). Reviews in Mineralogy and Geochemistry, 61. Mineralogical Society of America, Washington, D.C. and the Geochemical Society, St. Louis, Missouri, USA.CrossRefGoogle Scholar
Fleischer, V.D. (1984) Discovery, geology and genesis of copper-cobalt mineralisation at Chambishi Southeast prospect, Zambia. Precambrian Research, 25, 119133.CrossRefGoogle Scholar
Ganne, P., Cappuyns, V., Vervoort, A., Buve, L. and Swennen, R. (2006) Leachability of heavy metals and arsenic from slags of metal extraction industry at Angleur (eastern Belgium). Science of Total Environment, 356, 6985.CrossRefGoogle Scholar
Garlick, W.G. (1961) The syngenetic theory. Pp. 146165 in: The Geology of the Northern Rhodesian Copperbelt (Mendelsohn, F., editor). MacDonald, London.Google Scholar
Gorai, B., Jana, R.K. and Premchand, M. (2003) Characteristics and utilisation of copper slag — a review. Resources, Conservation and Recycling, 39, 299313.CrossRefGoogle Scholar
ICDD (2002) PDF-2 Database, Release 2002. International Centre for Diffraction Data: Newton Square, PA, USA.Google Scholar
Jones, R.T., Denton, G.M., Reynolds, Q.G., Parker, J.A.L. and van Tonder, G.J.J. (2002) Recovery of cobalt from slag in a DC arc furnace at Chambishi, Zambia. The Journal of the South African Institute of Mining and Metallurgy, 102, 510.Google Scholar
Kamona, A.F. and Nyambe, LA. (2002) Geological characteristics and genesis of stratiform sediment-hosted Cu-(Co) deposits, Zambian Copperbelt. In: Proceedings of the 11th IAGOD Quadrennial Symposium and Geocongress, Extended Abstracts (Miller, R.E., editor). Geological Survey of Namibia, Windhoek, Namibia (CD version).Google Scholar
Kierczak, L., Neél, C., Puziewicz, L. and Bril, H. (2009) The mineralogy and weathering of slag produced by the smelting of lateritic Ni ores, Szklary, Southwestern Poland. The Canadian Mineralogist, 47, 557572.CrossRefGoogle Scholar
Kříbek, B., Majer, V., Bezuško, P., Pašava, L., Adamovič, L., Nyambe, I., Liyungu, K. and Chibesakunda, F. (2006) Impact assessment of mining and processing of copper and cobalt ores on the environment in the Copperbelt, Zambia. Results of the Czech project of the development cooperation in 2006. MS Czech Geological Survey, Prague, Czech Republic, pp. 160162.Google Scholar
Kříbek, B., Majer, V., Veselovský, F. and Nyambe, I. (2010) Discrimination of lithogenic and anthropogenic sources of metals and sulphur in soils of the central-northern part of the Zambian Copperbelt Mining District: A topsoil vs. subsurface soil concept. Journal of Geochemical Exploration, 104, 6986.CrossRefGoogle Scholar
Lim, T.T. and Chu, L (2006) Assessment of the use of spent copper slag for land reclamation. Waste Management and Research, 24, 6773.CrossRefGoogle ScholarPubMed
Lottermoser, B.G. (2002) Mobilization of heavy metals from historical smelting slag dumps, north Queensland, Australia. Mineralogical Magazine, 66, 475490.CrossRefGoogle Scholar
Lottermoser, B.G. (2005) Evaporative mineral precipitates from a historical smelting slag dump, Rio Tinto, Spain. Neues Jahrbuch für Mineralogie, Abhandlungen, 181, 183190.CrossRefGoogle Scholar
Manasse, A. and Mellini, M. (2002) Archaeometallurgic slags from Kutná Hora. Neues Jahrbuch für Mineralogie, Monatshefte, 2002, 369384.CrossRefGoogle Scholar
McGowan, R.R., Roberts, S. and Boyce, A.J. (2006) Origin of the Nchanga copper-cobalt deposits of the Zambian Copperbelt. Mineralium Deposita, 40, 617638.CrossRefGoogle Scholar
Morimoto, N. and Koto, K. (1970) Phase relations of the Cu-S system at low temperatures: stability of anilite. American Mineralogist, 55, 106107.Google Scholar
Mukhopadhyay, S. and Jacob, K.T. (1996) Phase equilibria in the system CaO-CoO-SiO2 and Gibbs energies of formation of the quaternary oxides CaCoSi2O6, Ca2CoSi2O7 and CaCoSiO4 . American Mineralogist, 81, 963972.CrossRefGoogle Scholar
Osborn, E.F. and Muan, A. (1960) Phase Equilibrium Diagrams in Oxide Systems. American Ceramic Society and E. Orton, Jr, Ceramic Foundation, Columbus, OH, USA.Google Scholar
Parsons, M.B., Bird, D.K., Einaudi, M.T. and Alpers, C.N. (2001) Geochemical and mineralogical controls on trace element release from the Perm Mine base-metal slag dump, California. Applied Geochemistry, 16, 15671593.CrossRefGoogle Scholar
Piantone, P. (2004) Mineralogy and pollutant-trapping mechanisms. Comptes Rendus Geoscience, 336, 14151416.CrossRefGoogle Scholar
Piatak, N.M., Seal II, R.R. and Hammarstrom, J.M. (2004) Mineralogical and geochemical controls on the release of trace elements from slag produced by base- and precious-metal smelting at abandoned mine sites. Applied Geochemistry, 19, 10391064.CrossRefGoogle Scholar
Piatak, N.M. and Seal II, R.R. (2010) Mineralogy and the release of trace elements from slag from the Hegeler Zinc smelter, Illinois (USA). Applied Geochemistry, 25, 302320.CrossRefGoogle Scholar
Picot, P. and Johan, Z. (1982) Atlas of Ore Minerals. B.R.G.M., France and Elsevier, Netherlands, 458 pp.Google Scholar
Porada, H. and Berhorst, V. (2000) Towards a new understanding of the Neoproterozoic—early Palaeozoic Lufilian and northern Zambezi belts in Zambia and the Democratic Republic of Congo. Journal of African Earth Sciences, 30, 727771.CrossRefGoogle Scholar
Puziewicz, J., Zainoun, K. and Bril, H. (2007) Primary phases in pyrometallurgical slags from a zinc-smelting waste dump, Świętochłowice, Upper Silesia, Poland. The Canadian Mineralogist, 45, 11891200.CrossRefGoogle Scholar
Raghavan, V. (2006) Cu-Fe-S (copper-iron-sulfur). Journal of Phase Equilibria and Diffusion, 27, 290291.CrossRefGoogle Scholar
Ross, J. and de Vries, D. (2005) Mufulira smelter upgrade project — “Industry” smelting on the Zambian Copperbelt. Mopani Copper Mines PLC Internal Report, Kitwe, Zambia, 22 pp.Google Scholar
Sáez, R., Nocete, F., Nieto, J.M., Capitán, Á. and Rovira S. (2003) The extractive metallurgy of copper from Cabezo Juré Huelva, Spain: Chemical and mineralogical study of slags dated to the third millennium B.C. The Canadian Mineralogist, 41, 627638.CrossRefGoogle Scholar
Shannon, R.D. (1976) Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Ada Crystallographica A, 32, 751-767.Google Scholar
Šráček, O., Mihaljevič, M., Kříbek, B., Majer, V. and Veselovsky, F. (2010) Geochemistry and mineralogy of Cu and Co in mine tailings at the Copperbelt, Zambia. Journal of African Earth Sciences, 57, 14-30.CrossRefGoogle Scholar
Sugawara, T. and Akaogi, M. (2003) Calorimetric measurements of fusion enthalpies for Ni2SiO4 and Co2SiO4 olivines and application to olivine-liquid partitioning. Geochimica et Cosmochimica Ada, 67, 2683–269.CrossRefGoogle Scholar
Tsujimura, T. and Kitakaze, A. (2004) New phase relations in the Cu-Fe-S system at 800°C: constraint of fractional crystallization of a sulfide liquid. Neues J“hrbuch für Mineralogie, Monatshefte, 2004, 433444.CrossRefGoogle Scholar
Unrug, R. (1983) The Lufilian Mc: a microplate in the Pan-African collision zone of the Congo and the Kalahari cratons. Precambrian Research, 21, 181196.CrossRefGoogle Scholar