Comparison of Enhancement of Mineral Liberation by HPGR, Microwave, and Electrical Disintegration on Copper Ore

Ryo Kawarabuki, Masato Kosugi, J.V. Satur, K. Mitsuhashi, M. Kawata, Yoshiaki Kon, B. Calabia, T. Takagi, G. Dodbiba, Kengo Horiuchi, Chiharu Tokoro, Yusuke Iwazaki, and Toyohisa Fujita

49th Annual Conference of Metallurgists, Vancouver, Canada, August 27-30, 2017.


The liberation of copper minerals is important in ensuring high flotation efficiency in copper sulfide flotation. The high pressure grinding roll (HPGR), microwave (MW), and electric disintegration (ED) feature enhanced liberation over conventional comminution machines such as jaw crushers and ball mills by producing internal stresses on minerals or mineral grain boundaries through high compressive forces, thermal expansion of minerals, and pulsed high voltage discharges. In this study, each of these methods was applied before ball mill grinding to investigate its effect on enhancing the liberation of copper minerals in a fine-grained, low grade copper ore. The copper minerals are chalcocite, bornite, and chalcopyrite and their grain sizes range from 10-500 µm. The gangue minerals are calcite, quartz, and feldspar. The liberation of the copper minerals by the different methods was analyzed using the mineral liberation analyzer (MLA) and compared. Results showed that the HPGR crushing was the most effective for enhancing copper mineral liberation. HPGR bench-scale testwork was then conducted on the copper ore and flotation was applied on a HPGR-treated sample to confirm the improvement in the flotation performance by applying HPGR.


CEEC acknowledges and thanks the Canadian Institute of Mining, Metallurgy and Petroleum (CIM), the Metallury and Materials Society (MetSoc) and organising committee for organising the COM 2017 Conference of Metallurgists hosting World Gold and Nickel-Cobalt.

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