Liberation is the physical release of valuable minerals from their waste gangue. It is a necessary intermediate step between mining and the separation/concentration operations. One easy way to quantify mineral liberation is to capture digital images of polished sections of particles or drill cores in a Scanning Electron Microscope (SEM) and process these images automatically using specialized computer software. Measuring linear or areal grade from digital SEM images is fairly easy and can be realized by various means from simple image processing software to very expensive integrated equipment like QEM*SEM. Advanced mathematical theories (Stereological Correction) are however necessary to reconstruct volumetric information from these linear or areal measurements. Only volumetric information is useful in quantitatively characterizing a process and MTI can generate this quickly and reliably. Furthermore, data interpretation and modeling is of the utmost importance if one wants to make use of the measurements and MTI's personnel has proven extensive experience in this domain.
Liberation studies on drill core
sections should be performed on a routine basis to test for ore
variability, identify different ore types and assess needed flowsheet
modifications to accommodate the ore change. Performed early
during the mine planning stages, mineral liberation study will
give invaluable information to assess the viability of an ore
Within the next decade, liberation measurement is bound to become as popular and necessary as the washability curve is in the coal processing industry today. Any mining operation dealing with a separation process in its flowsheet can benefit from a liberation study. To date, successful applications include coal, iron ores, complex sulfur deposits, gravity separation of gold, apatite and sphalerite-dolomite ores.