Natural Resources Canada, Mining and Mineral Sciences Laboratories,555 Booth St., Ottawa, ON, K1A 0G1, Canada..
To simplify programming, image analyzers commonly measure either linear intercepts or the areas of particles and grains to determine liberation based on polished section mounts. However, the concentration of minerals by flotation is based on reagents that interact with the exposed surfaces of the minerals. Thus, it is often perceived that image analyzers should measure the perimeter of the mineral of interest in the ore particles. A comparative liberation study of thirteen samples collected from a flotation plant processing a complex base metal sulfide ore showed that the liberation of the ore minerals determined by area measurements is very similar to the liberation determined by the exposed perimeters. The liberation determined by exposed perimeters is more appropriate only for those cases where the mineral texture is so complex that it is retained in the small particles generated in conventional grinding operations.
R. Lastra, "A Comparison Of Liberation Determinations By Particle Area Percentage And Exposed Particle Perimeter Percentage In A Flotation Concentrator," Journal of Minerals and Materials Characterization and Engineering, Vol. 1 No. 1, 2002, pp. 31-37. doi: 10.4236/jmmce.2002.11003.
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