Open Collections

Characterizing waste rock using automated quantitative electron microscopy

University of British Columbia

The leaching of metals from waste rock is directly related to the mineralogical composition of the rock. The overall study objective was to evaluate the application of automated quantitative electron microscopy to weathering waste rock. The value of mineral liberation analysis in optimizing mineral processing operations has been well documented. Application of automated mineralogical techniques, such as the Mineral Liberation Analyzer, to environmental studies is less common with no waste rock characterization studies found that specifically use the Mineral Liberation Analyzer. Mineral Liberation Analyzer methodology limitations and advantages were explored in the context of detection and quantification of primary and secondary metal-associated mineral phases. Mineral Liberation Analyzer application to waste rock weathering studies was assessed using laboratory, field cell, and experimental pile samples which were separated into particle-size fractions. Mineral Liberation Analyzer characterization included bulk modal and metal-associated mineralogy, size distribution, and mineral liberation, association, and exposure or availability (to weathering processes) and mineralogical features useful to an environmental modeller. The Mineral Liberation Analyzer consisted of a FEI Quanta 600 scanning electron microscope equipped with dual Bruker-AXS silicon drift detectors, tungsten filament and proprietary software. The Mineral Liberation Analyzer demonstrated characterization of Antamina mine waste rock which would aid the understanding of weathering processes at this and other sites, such as tailings and heap leach activity. Important mineralogical and elemental features determined were: availability / exposure, particle / grain size and shape, association (such as locking and potential mineral-mineral interactions), quantity and type (such as crystal structure reactivity), fractures and porosity. The scope of this study does not extend to linking lithology to secondary mineralogy. The Mineral Liberation Analyzer, in conjunction with geochemistry, particle surface analysis tools, chemical speciation modeling and diagnostic sequential leach can advance waste rock characterization, to improve mitigation strategies for waste rock drainage.

Text

2013-05-18

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/44496

Mining Engineering

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/