Characterization of solid–liquid settling suspensions using Electrical Impedance Tomography: A comparison between numerical, experimental and visual information

Abstract

To address the limitation of traditional characterization techniques, over the past two decades, non-invasive monitoring tomography techniques have been employed in the study of multiphase systems. Amongst them, electrical tomography offers several advantages when compared with the traditional methods, such as providing information on the boundaries between mixture components, flow regimes, concentration distribution in the cross section of conveying pipes and mixing zones distribution in stirred tanks, amongst others, resulting in a better understanding of the monitored process and as a means of validating physical models.With the present study the objective was to validate experimental particle distribution profiles attained with an EIT apparatus, for two different average particle sizes, 0.15 and 0.5mm, and increasing volumetric concentration up until 11.0% (v/v), in a horizontal flow pipe cross section. To this end, experimental particle distribution profiles from a Sampling Probe (SP), numerical particle distribution profiles obtained using the Mixture Model coupled with a High Reynolds k–ɛ turbulence model and visual inspection served as a comparison basis (Goeree et al., 2016; Silva et al., 2015). Analysis of the resulting 1D particle distribution profiles from both experimental techniques and numerical data shows a good agreement, thus, demonstrating the potential of the EIT in the characterization of solid–liquid suspensions flow for the range of particle concentrations and sizes tested.