The capabilities and opportunities of the application of automated mineralogy for the characterization of lithium-bearing zinnwaldite-micas are critically assessed. Samples of a crushed greisen-type ore comprising mostly of quartz, topaz and zinnwaldite (Li-rich mica) were exposed to further comminution by cone crusher and high voltage pulse power fragmentation. Product properties were analyzed by using a Mineral Liberation Analyser (MLA) and the obtained mineralogical and mineral processing relevant parameters were carefully evaluated with special focus on the characteristics of zinnwaldite. The results illustrate that both samples contain a significant quantity of very fine particles that are products of comminution. The modal mineralogy in the different sieve fractions is characterized by the accumulation of minerals of low hardness in the finest fraction and the enrichment of topaz, having a high hardness, in the somewhat larger fractions. Based on the results of mineral association data for zinnwaldite, a displacement of the muscovite-quartz ratio, in comparison to the results of modal mineralogy, was observed by indicating good quartz-zinnwaldite boundary breakage and weak muscovite-zinnwaldite breakage. Liberation as well as mineral grade recovery curves indicate that fraction 1000 to +500 μm is most suitable for beneficiation. The results of this study demonstrate that SEM-based image analysis, such as MLA, can effectively be used to investigate and evaluate phyllosilicate minerals in a fast and precise way. It is shown that the results of MLA investigations, such as modal mineralogy, are in good agreement with other analytical methods such as quantitative X-ray powder diffraction.
References
[1]
L. Beloqui, J. M. Usategui, E. Wang, F. Shi and E. Manlapig, “Pre-Weakening of Mineral Ores by High Voltage Pulses,” Minerals Engineering, Vol. 24, No. 5, 2011, pp. 455-462.
http://dx.doi.org/10.1016/j.mineng.2010.12.011
[2]
R. Fandrich, Y. Gu, D. Burrows and K. Moeller, “Modern SEM-Based Mineral Liberation Analysis,” International Journal of Mineral Processing, Vol. 84, No. 1-4, 2007, pp. 310-320.
[3]
Y. Gu, “Automated Scanning Electron Microscope Based Mineral Liberation Analysis an Introduction to JKMRC/ FEI Mineral Liberation Analyser,” Journal of Minerals and Materials Characterization and Engineering, Vol. 2, No. 1, 2003, pp. 33-41.
[4]
P. Atanasova, “Mineralogy, Geochemistry and Age of Greisen Mineralization in the Li-Sn(-W) Deposit Zinnwald, Eastern Erzgebirge, Germany,” Master Thesis, Technische Universitat Bergakademie, Freiberg, 2012.
[5]
T. G. Goonan, “Lithium Use in Batteries,” U.S. Geological Survey Circular 1371, 2012.
[6]
E. Siame and R. D. Pascoe, “Extraction of Lithium from Micaceous Waste from China Clay Production,” Minerals Engineering, Vol. 24, No. 14, 2011, pp. 1595-1602.
http://dx.doi.org/10.1016/j.mineng.2011.08.013
[7]
L. Baumann, E. Kuschka and T. Seifert, “Lagerst?tten des Erzgebirges,” ENKE im Georg Thieme Verlag, Stuttgart, 2000.
[8]
K. Govindaraju, I. Rubeska and T. Paukert, “Report on Zinnwaldite ZW-C Analysed by Ninety-Two GIT-IWG Member-Laboratories,” Geostandards Newsletter, Vol. 18, No. 1, 1994, pp. 1-42.
http://dx.doi.org/10.1111/j.1751-908X.1994.tb00502.x
[9]
H. Bluhm, W. Frey, H. Giese, P. Hoppé, C. Schulthei? and R. Str??ner, “Application of Pulsed HV Discharges to Material Fragmentation and Recycling,” IEEE Transactions on Dielectrics and Electrical Insulation, Vol. 7, No. 5, 2000, pp. 625-636.
http://dx.doi.org/10.1109/94.879358
[10]
E. Dal Martello, S. Bernardis, R. B. Larsen, G. Tranell, M. Di Sabatino and L. Arnberg, “Electrical Fragmentation as a Novel Route for the Refinement of Quartz Raw Materials for Trace Mineral Impurities,” Powder Technology, Vol. 224, 2012, pp. 209-216.
http://dx.doi.org/10.1016/j.powtec.2012.02.055
[11]
B. R. Jackson, A. F. Reid and J. C. Wittemberg, “Rapid Production of High Quality Polished Sections for Automated Image Analysis of Minerals,” Proceedings of the Australasian Institute for Mining and Metallurgy, Vol. 289, 1984, pp. 93-97.
[12]
M. MacDonald, B. Adair, D. Bradshaw, M. Dunn and D. Latti, “Learnings from Five Years of On-Site MLA at Kennecott Utah Copper Corporation,” Proceedings of the 10th International Congress for Applied Mineralogy (ICAM), Trondheim, 1-5 August 2011, pp. 419-426.
[13]
K. Bachmann, S. Haser, T. Seifert and J. Gutzmer, “Preparation of Grain Mounds of Heterogeneous Mineral Concentrates for Automated Mineralogy—An Example of Li-Bearing Greisen from Zinnwald, Saxony, Germany,” Schriftenreihe der Deutschen Gesellschaft für Geowissenschaften, Vol. 80, 2012, p. 395.
[14]
N. Vlachos and I. T. H. Chang, “Graphical and Statistical Comparison of Various Size Distribution Measurement Systems Using Metal Powders of a Range of Sizes and Shapes,” Powder Metallurgy, Vol. 54, No. 4, 2011, pp. 497-506.
http://dx.doi.org/10.1179/003258910X12707304455022
[15]
H. Bolduan, A. L?chelt and F. Malasek, “Zur Geologie und Mineralisation der Lagerst?tte Zinnwald (Cinovec),” Freiberger Forschungshefte, Vol. C218, 1967, pp. 35-52.
[16]
M. Sala, “Geochemische und Mineralogische Untersuchungen an Alterierten Gesteinen aus dem Kuppelbereich der Lagerstaette Zinnwald (Osterzgebirge),” Ph.D. Thesis (Dissertation), Technische Universitat Bergakademie, Freiberg, 1999.
[17]
O. Seibel, “Kartierung Ausgew?hlter Profile im Grubenbereich Zinnwald unter Besonderer Berücksichtigung Paragenetischer und Struktureller Aspekte von Granithochlagen,” Master Thesis (Diplomarbeit), Bergakademie Freiberg, Freiberg, 1975.
[18]
T. Lei?ner, T. Mütze, K. Bachmann, S. Rode, J. Gutzmer and U. A. Peuker, “Evaluation of Mineral Processing by Assessment of Liberation and Upgrading,” Minerals Engineering, Vol. 53, 2013, pp. 171-173.
http://dx.doi.org/10.1016/j.mineng.2013.07.018
[19]
Min Assist, “What Is a Theoretical Grade-Recovery Curve? An Example,” 2009.
http://www.minassist.com.au/blog/what-is-a-theoretical-grade-recovery-curve-an-example/
[20]
J. D. Miller, C. L. Lin, L. Hupka and M. I. Al-Wakeel, “Liberation-Limited Grade/Recovery Curves from X-ray Micro CT Analysis of Feed Material for the Evaluation of Separation Efficiency,” International Journal of Mineral Processing, Vol. 93, No. 1, 2009, pp. 48-53.
http://dx.doi.org/10.1016/j.minpro.2009.05.009
[21]
E. Wang, F. Shi and E. Manlapig, “Mineral Liberation by High Voltage Pulses and Conventional Comminution with Same Specific Energy Levels,” Minerals Engineering, Vol. 27-28, 2012, pp. 28-36.
http://dx.doi.org/10.1016/j.mineng.2011.12.005