Comparison of different 2D image analysis measurement techniques for the shape of talc particles produced by different media milling

Abstract

Talc, which is an extremely versatile industrial mineral, has found increasing number of uses in various industries such as paint, paper, plastic, ceramic and cosmetic. As it is well known, the particle shape is one of the main properties affecting the behavior and properties of mineral particles, especially for the bubble-particle attachment in flotation.In this study, shape characteristics of talc particles produced by laboratory ball and rod mills were determined by automated image analysis using Malvern Morphologi® G3 instrument. The results were compared by previous studies on the same samples that used other shape characterization techniques namely Scanning Electron Microscope (SEM) (Yekeler et al., 2004; Hiçyılmaz et al., 2004) and Clemex image analysis system (Ulusoy, 2008). About 10,058 particles for ball milled product and 7086 particles for rod milled product were measured for the shape analysis by the Malvern Morphologi® G3 instrument. They were expressed in terms of Aspect ratio, HS Circularity and Elongation and compared by applying t-test using the software Statistical Package for Social Science (SPSS) with a 0.05 significance level. t-Test revealed that, the difference between the image data group for different mill products are significant with a 95% confidence level.Although lower sample population was used for the SEM and Clemex analysis techniques than for the new technique Malvern Morphologi® G3, there is a clear difference in the particle shape obtained by different grinding methods for the talc mineral used. The determined shape property depends on the measurement technique applied. However, the results are in good agreement with each other by this study. i.e., more elongated talc particles were obtained by rod mill product.