Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

A new method to measure and quantify the 3D mineralogical composition of particulate
materials using X-ray computed micro-tomography (CT) is presented. The new method is
part of a workflow designed to standardize the analysis of particles based on their
microstructures without the need to segment the individual classes or grains. Classification
follows a decision tree with criteria derived from particle histogram parameters that are
specific to each microstructure, which in turn can be identified by 2D-based automated
quantitative mineralogy. The quantification of mineral abundances is implemented at the
particle level according to the complexity of the particle by taking into consideration the
partial volume effect at interphases. The new method was tested on two samples with
different particle size distributions from a carbonate rock containing various microstructures
and phases. The method allowed differentiation and quantification of more mineral classes
than traditional 3D image segmentation that uses only the grey-scale for mineral classification.
Nevertheless, due to lower spatial resolution and lack of chemical information, not all
phases identified in 2D could be distinguished. However, quantification of the mineral
classes that could be distinguished was more representative than their 2D quantification,
especially for coarser particle sizes and for minor phases. Therefore, the new 3D method
shows great potential as a complement to 2D-based methods and as an alternative to traditional
phase segmentation analysis of 3D images. Particle-based quantification of mineralogical
and 3D geometrical properties of particles opens new applications in the raw
materials and particle processing industries.