Image analysis: A useful tool for porous media characterization

Abstract

In chemical engineering processes as well as in everyday life situations, porous media are commonly and frequently encountered: packed beds of cylindrical catalysts used in the fine chemical manufacturing sector or in the petroleum industry, packed beds of granular activated carbon or beds of multisized resin beads applied for water treatment, carbon activated felts or fabrics used for air filtration in cars. The optimized design of these processes needs a careful characterization of the porous medium structure. In particular, the study of void distribution often allows detecting areas of fiber or particle maldistribution responsible for dysfunction. Another point of interest concerns the study and characterization of the clogging phenomenon during filtration in order to estimate, for example, the filter lifetime. Amongst the few experimental techniques that can be used to this end [1], image analysis of consolidated samples proves to be a useful and efficient but seldom used tool [1-6]. However, this technique is currently applied in the fields of geology and materials science in order to characterize minerals or to verify the quality of metallic pieces. The aim of this paper is to enlighten different examples of diagnostic applications that can be made through this technique in the field of chemical engineering.