Effect of Flow Field on Colloid Deposition in Filtration Process of Polystyrene Latex Particles through Columns Packed with Glass Beads.

Abstract

The effect of flow field on the deposition rate of colloidal particles onto solid surface in a column packed with spherical collectors was investigated theoretically and experimentally. A new analysis for calculating the colloid deposition efficiency was developed. The analysis includes the effect of the flow field on the deposition of a colloidal particle through the interactive potential barrier between the particle and the solid surface. The deposition behavior of polystyrene latex particles (diameter: 102 nm) in transport process through columns (length: 100 mm) packed with glass beads (diameter: 0.35–0.40 mm) was observed. The colloid deposition efficiencies calculated by the new analysis were comparable with those obtained by the experiments. The result indicates that the effect of the flow field would cause the difference between the flow velocity dependence of the efficiency obtained by a classical analysis and that by the experimental results. The colloid deposition efficiencies were also obtained by estimating the deposited particles onto the glass beads surface suspended in the colloidal suspension from the SEM observation of the glass beads surface. The effect of the heterogeneity of the collector surface was discussed by calculating the colloid deposition efficiency using the evaluated interaction potential between the particle and the heterogeneous collector surface.