Mass transfer coefficients for suspended particles in agitated vessels and bubble columns

Abstract

Mass transfer coefficients of suspended particles were measured in agitated vessels and in bubble columns. Four sizes of agitated vessels (diameter: 9.5, 17.5, 20, 40 cmϕ) including both fully baffled and non-baffled conditions and two sizes of bubble columns (diameter: 10, 20 cmϕ) were used. Particle sizes ranged from 60 to 1100 µϕ including both spherical beads (ion exchange resin) and granules (benzoic acid, KMnO4, and β-naphthol). We correlated the mass transfer coefficients using the surface factor as Sh=[2+0.4(ℰdp4/v3)1/4·Sc1/3]·ϕcwith a standard deviation of 30.8% for the Sherwood number. Sh[—]: Sherwood number, ℰ [cm2/sec3]: rate of energy dissipation, dp[cm]: specific surface diameter, v [cm2/sec]: kinematic viscosity, Sc [—]: Schmidt number and ϕc[—]: surface factor. © 1974, The Society of Chemical Engineers, Japan. All rights reserved.