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Since the particle size, shape, specific surface area, and purity of the ground calcium carbonate (GCC) decide its usability in the paper, paint, and plastic industries, the effect of grinding is important. However, the effect of stirred and ball mill grinding on the particle shape of GCC by dynamic image analysis (DIA) is still lacking in the literature. Therefore, the aim of this study is to compare the aspect ratio at the same fineness (d97 = 50 μm) and evaluate other properties such as color, and surface area of GCC particles by stirred and ball mill grindings. DIA results showed that particles produced by the ball mill had higher aspect ratio values than those by the stirred mill. This was attributed to the impact, and attrition breakage modes produced by the ball and stirred mill, respectively. This conclusion is supported by XRD and SEM. Finally, the results related to physical properties such as aspect ratio, surface area, and whiteness are discussed depending on the usage area of GCC. [ABSTRACT FROM AUTHOR]

Although grinding kinetics has been the subject of many researches, there is no research examining the shape kinetics of particles ground by different mills using dynamic image analysis (DIA) in the literature. In this investigation, how the shapes of quartz particles change over time at two different size fractions in two different mills is modeled using the latest image analysis technique, since particle shape of mineral is important in flotation and hydraulic fracturing processes. Empirical time-dependent shape models based on the correlation between average circularity (Cav.) and bounding rectangle aspect ratio (BRARav.) parameters and grinding time for vibratory disc mill and ball milled particles are established with high R2 values by different fitting. Furthermore, average shape values of particles ground by the mills depending on grinding time were predicted for two size fractions. It was found that, Cav. data can be better described by linear fitting equations, on the other hand BRARav. data can be better represented by power fitting equations. Since predicted and measured shape values were found close to each other, this approach provides useful information for estimating the milling time required to produce the particles by milling (with less energy and cost) appropriately for intended use. [ABSTRACT FROM AUTHOR]