Bed voidage correlation in fluidized bed biofilm reactor

Abstract

A simple predictive correlation for bed voidage in a three-phase fluidized bed biofilm reactor (FBBR) has been proposed in this study, based on a relationship between the effective up-flow superficial liquid velocity (U-L) and the corresponding up-few superficial liquid velocity in a three-phase FBBR (U-L'). The experimental observations of bed voidage both for this study as well as for experimental data from a study Trinet et al. for a three-phase FBBR compared reasonably well with the model predictions developed in this study, with mean deviations of 0.26% and 7%, respectively. Further, published experimental observations of bed voidage in a two-phase FBBR agreed well with the model predictions, with mean deviations of 26.4%, 5.2%, and 9.7% for studies conducted by Mulcahy and Shieh, Ngian and Martin, and Setiadi, respectively, and with a mean deviation of 18.7% for the total published experimental data (297 points) of the above researchers.