Use of X-ray Micro Computed Tomography for the Investigation of Drying and Salt Precipitation in a Regular Glass Bead Structure

Micro computed tomography is a powerful tool for the inspection of porous media since it essentially provides the possibility to reconstruct a three dimensional volume of an object at micrometric spatial resolution. The technique is non-intrusive, while still being capable of dealing with matter that is opaque at the wavelengths of visible light. The processing of the obtained data such as segmentation and morphology characterization in multi-phase porous systems is a challenging research topic for the comprehension of countless physical problems in a variety of technical applications. This research project is dedicated to the investigation and optimization of all aspects along the process chain, starting from the preparation of adequate porous samples towards the acquisition of the computed tomographies and data processing until pore-scale fluid displacement processes in multi-phase systems can eventually be visualized and characterized. Presented here are the production process of a regular glass bead pack, the data acquisition and processing methods and the obtained results for tomographic experiments during which the pack is containing distilled water, doped with potassium iodide and air and is subjected to drying in ambient atmosphere. The sample design allows validation of values derived from tomographic data with analytically predictable values.