mineral processing, electrum, flotation, scanning electron microscopy
Abstract :
[en] The gold ore mined at the Krumovgrad mine, Bulgaria is processed by flotation following grinding and regrinding stages securing the targeted liberation size of the electrum which is the principal precious metal-bearing mineral.
The findings from a SEM-based automated mineralogy study aiming to quantify electrum occurrences in the processing scheme are presented and the implications of these characteristics on precious metals recovery are discussed. It has been found that Au/Ag grade ratios in the electrum tend to increase in the concentrate streams and decrease in the tailings. The mineralogical analysis indicated that in comparison to the precious metals grains met in the reground rougher concentrate, those detected in the cleaner concentrate are characterized by about 10 % higher gold content. Moreover, particles possessing zones largely enriched in gold (zones where electrum is detected as having at least 90 % gold grade) are more frequently observed in the cleaner concentrate.
Grains morphology suggests that the stirred media detritor (SMD) used in the regrinding circuit does not significantly modify particle shape. Likewise, opting for a staged flotation reactors (SFRs) as the main flotation units seem to be a judicious choice by maintaining conditions favouring the recovery of the ultrafine gold.
Research center :
GeMMe - Mineral Processing and Recycling
Disciplines :
Geological, petroleum & mining engineering
Author, co-author :
Demeusy, Bastien
Madanski, Deyan
Bouzahzah, Hassan ; Université de Liège - ULiège > Département ArGEnCo > Géoressources minérales & Imagerie géologique
Gaydardzhiev, Stoyan ; Université de Liège - ULiège > Département ArGEnCo > Traitement et recyclage des matières minérales (y compris les sols)
Language :
English
Title :
Mineralogical study of electrum grain size, shape and mineral chemistry in process streams from the Krumovgrad mine, Bulgaria
Agorhom, E.A., Lem, J.P., Skinner, W., Zanin, M., Challenges and opportunities in the recovery/rejection of trace elements in copper flotation-a review. Miner. Eng. 78 (2015), 45–57, 10.1016/j.mineng.2015.04.008.
Agorhom, E.A., Skinner, W., Zanin, M., Post-regrind selective depression of pyrite in pyritic copper–gold flotation using aeration and diethylenetriamine. Miner. Eng. 72 (2015), 36–46, 10.1016/j.mineng.2014.11.019.
Aksoy, B.S., Yarar, B., 1989. Natural hydrophobicity of native gold flakes and their flotation under different conditions. In Processing of Complex Ores (pp. 19–27). Elsevier. Doi: 10.1016/B978-0-08-037283-9.50007-X.
Allan, G.C., Woodcock, J.T., A review of the flotation of native gold and electrum. Miner. Eng. 14:9 (2001), 931–962, 10.1016/S0892-6875(01)00103-0.
Allen, J., 2013, November 13. Stirred miling machine development and application extension.
Banisi, S., An investigation of the behaviour of gold in grinding circuits. National Library of Canada = Bibliothèque nationale du Canada, 1992.
Blazy, P., Jdid, E.-A., 2000. Flottation—Mécanismes et réactifs. 25.
Chipfunhu, D., Zanin, M., Grano, S., The dependency of the critical contact angle for flotation on particle size – Modelling the limits of fine particle flotation. Miner. Eng. 24:1 (2011), 50–57, 10.1016/j.mineng.2010.09.020.
Corrans, I.J., Angove, J.E., Ultra fine milling for the recovery of refractory gold. Miner. Eng. 4:7–11 (1991), 763–776, 10.1016/0892-6875(91)90064-3.
Dobby, G., The staged flotation reactor—Glenn Dobby of Woodgrove Technologies. Canadian Institute of Mining, Metallurgy and Petroleum., 2016 February 24 https://www.youtube.com/watch?v=7xoNinZKlSc&ab_channel=CanadianInstituteofMining%2CMetallurgyandPetroleum.
Dunne, R., 2016. Flotation of Gold and Gold-Bearing Ores. In Gold Ore Processing: Project Development and Operations. http://univ.scholarvox.com.bases-doc.univ-lorraine.fr/reader/docid/88833261/page/344.
Faraz, S., Hossna, D., Rezgar, B., Piroz, Z., Improved recovery of a low-grade refractory gold ore using flotation–preoxidation–cyanidation methods. Int. J. Min. Sci. Technol. 24:4 (2014), 537–542, 10.1016/j.ijmst.2014.05.018.
Goranov, A., Atanasov, G., Lithostratigraphy and formation conditions of Maastrich- tian -Paleocene deposits in Krumovgrad District. Geologica Balcanica 22:3 (1992), 71–92.
Klimpel, R.R., Industrial experiences in the evaluation of various flotation reagent schemes for the recovery of gold. Mining, Metallurgy & Exploration 16:1 (1999), 1–11, 10.1007/BF03402850.
Leppinen, J.O., Yoon, R.-H., Mielczarski, J.A., FT-IR studies of ethyl-xanthate adsorption on gold, silver and gold-silver alloys. Colloids Surf., 61, 1991, 10.1016/0166-6622(91)80309-C.
Lichter, J., Davey, G., Selection and sizing of ultrafine and stirred grinding mills. Advances in comminution. Society for Mining, Metallurgy, and Exploration, 2006.
Lofthouse, C.H., Johns, F.E., The Svedala (ECC International) detritor and the metals industry. Miner. Eng. 12:2 (1999), 205–217, 10.1016/S0892-6875(98)00132-0.
Marchev, P., Singer, Brad. S., Jelev, D., Hasson, S., Moritz, R., & Bonev, N. (2004). The Ada Tepe deposit: A sediment-hosted, detachment fault-controlled, low-sulfidation gold deposit in the Eastern Rhodopes, SE Bulgaria. Schweizerische Mineralogische Und Petrographische Mitteilungen, 84, 59–78. Doi: 10.5169/seals-63739.
Marchev, P., Singer, B., Andrew, C., Hasson, S., Moritz, R., Bonev, N., Characteristics and preliminary 40Ar/39Ar and 87Sr/86Sr data of the Upper Eocene sedimentary-hosted low-sulfidation gold deposits Ada Tepe and Rosino. 2003, Possible relation with core complex formation. Mineral Exploration and Sutainable Development, SE Bulgaria, 1193–1196.
Marinova, I., Preliminary data on the morphology of electrum from the layer-like pervasive silicification in Stenata outcrop, Khan Krum gold deposit, SE Bulgaria. Proceedings of “Geosciences 2006” National Conference, 2006, 113–116.
Marinova, I., Morphometry of electrum from layer-like pervasive silicification in stenata outcrop, low-sulfidation Khan Krum gold deposit, SE Bulgaria. Comptes Rendus de l'Académie Bulgare Des Sciences: Sciences Mathématiques et Naturelles, 60, 2007, 9.
Marinova, I., Morphology of electrum from Khan Krum gold deposit, Krumovgrad goldfield, eastern Rhodope mountain, SE Bulgaria. Geologica Macedonica 2 (2008), 111–120.
Marinova, I., A conceptual model for formation of bonanza electrum along steep veinlets in epithermal low-sulfidation gold deposits. Case study from the Khan Krum deposit, SE Bulgaria., 2014, 10.13140/2.1.4963.3282.
Márton, I., Moritz, R., Spikings, R., Application of low-temperature thermochronology to hydrothermal ore deposits: Formation, preservation and exhumation of epithermal gold systems from the Eastern Rhodopes Bulgaria. Tectonophysics 483:3–4 (2010), 240–254, 10.1016/j.tecto.2009.10.020.
Matis, K.A., Gallios, G.P., Kydros, K.A., Separation of fines by flotation techniques. Sep. Technol. 3:2 (1993), 76–90, 10.1016/0956-9618(93)80007-E.
Mazzinghy, D.B., Galéry, R., Schneider, C.L., Alves, V.K., Scale up and simulation of VertimillTM pilot test operated with copper ore. J. Mater. Res. Technol. 3:1 (2014), 86–89, 10.1016/j.jmrt.2013.11.001.
McGrath, T.D.H., O'Connor, L., Eksteen, J.J., A comparison of 2D and 3D shape characterisations of free gold particles in gravity and flash flotation concentrates. Miner. Eng. 82 (2015), 45–53, 10.1016/j.mineng.2015.04.022.
O'Connor, C.T., Dunne, R.C., The flotation of gold bearing ores—A review. Miner. Eng. 7:7 (1994), 839–849, 10.1016/0892-6875(94)90128-7.
Shi, F., Morrison, R., Cervellin, A., Burns, F., Musa, F., Comparison of energy efficiency between ball mills and stirred mills in coarse grinding. Miner. Eng. 22:7–8 (2009), 673–680, 10.1016/j.mineng.2008.12.002.
Stefanova, V., Serafimovski, T., Tasev, G., Native gold composition and morphology through the mineral processing stages at the Bucim copper mine Republic of macedonia. Geologica Macedonica 34:1 (2018), 59–74.
Taylor, B.E., Epithermal gold deposits, 8, 1995, p. 8, 10.4095/208000.
Teague, A.J., Van Deventer, J.S.J., Swaminathan, C., A conceptual model for gold flotation. Miner. Eng. 12:9 (1999), 1001–1019, 10.1016/S0892-6875(99)00087-4.
Tsintsov, Z., Ivanov, I.P., Features of Au–Ag alloys in the epithermal low-sulfidation Au–Ag khan krum deposit, eastern Rhodopes. Comptes Rendus de l'Académie Bulgare Des Sciences: Sciences Mathématiques et Naturelles, 65(11), 2012, 12.
Tsintsov, Z., Popov, H., Features of placer gold from the eluvial-deluvial sediments of Ada Tepe peak and their significance for the ancient ore mining. Comptes Rendus de l'Académie Bulgare Des Sciences: Sciences Mathématiques et Naturelles 65:6 (2012), 831–838.
Woods, R., Basilio, C.I., Kim, D.S., Yoon, R.-H., Chemisorption of ethyl xanthate on silver—Gold alloys. Colloids Surf A Physicochem Eng Asp 83:1 (1994), 1–7, 10.1016/0927-7757(93)02649-Y.
Xia, W., Role of particle shape in the floatability of mineral particle: An overview of recent advances. Powder Technol., 13, 2017.
Xiao, X., Zhang, G., Feng, Q., Xiao, S., Huang, L., Zhao, X., Li, Z., The liberation effect of magnetite fine ground by vertical stirred mill and ball mill. Miner. Eng. 34 (2012), 63–69, 10.1016/j.mineng.2012.04.004.
Yannopoulos, J.C., The Extractive Metallurgy of Gold. Springer, US, 1991, 10.1007/978-1-4684-8425-0.
Yianatos, J., Bergh, L., Vinnett, L., Díaz, F., Modeling of residence time distribution in regrinding Vertimill. Miner. Eng. 53 (2013), 174–180, 10.1016/j.mineng.2013.08.006.
Zhou, J.Y., Cabri, L.J., Gold process mineralogy: Objectives, techniques, and applications. JOM 56:7 (2004), 49–52, 10.1007/s11837-004-0093-7.
