Simplified correlations of axial dispersion coefficient and porosity in a solid-liquid fluidized bed adsorber

Abstract The aim of the present work is to propose a simple, reliable and effective model of hydrodynamics in fluidized bed reactor (FBR). The long-term objective of these models is to be able to use them for modeling and optimization of adsorption processes in fluidized bed columns. Residence time distribution (RTD) and porosity (e) of the bed were determined as a function of flow rate Q v  = 210–1000 L/h, and temperature T  = 20–40 °C. Polynomial models with interaction terms were developed to study the influence of T and Qv on two responses: porosity and axial dispersion coefficient (ADC). The quality of regression model equations was evaluated using the analysis of variance (Minitab16). The porosity of the bed increases with the square of the superficial velocity up to a peak of 0.92 at the rate of 1000 L/h. Among the correlations of the literature on the porosity of the fluidized bed, those of Miura et al. (2001) and Riba et al. (1977) are closest to our experimental data (with a 4% and 16% error respectively). The axial dispersion coefficient of the liquid phase increases monotonically with liquid velocity. A theoretical minimal D ax values can be achieved at temperatures higher than 34 °C and flow rate of 210 L/h.