Drying Kinetics of Particulate Corundum Layers

The results of studies on drying of layers of particulate corundum performed with digital neutron radiography are presented. The statistical analysis of images was employed to reveal main features of the drying process. It is shown that the first period of drying proceeds within the whole body of the sample. Marked signatures of the end of first period of drying were found for sample mass, temperature, average image brightness as well as standard deviation of brightness time evolutions for the system composed of fine grains. The chaotic nature of this period is delineated by a distinct maximum in the standard deviation of sample image brightness. The presence of the drying front moving from the open surface to the sample bottom is proven to be an attribute of the advanced drying period.