Development of fixed-bed adsorber correlation models

The adsorption of three single-component acid dyes onto activated carbon ha s been studied using fixed-bed adsorption. Conventional simplified design m ethods, namely, bed depth service time (BDST) and empty-bed residence time (EBRT) models, were applied to the experimental breakthrough curve data but failed to correlate these data. Consequently, modifications have been deve loped that enable modified BDST and EBRT models to be applied and to correl ate the experimental data very accurately. The modification is based on an expression to correlate the residence time in the adsorption bed with the t ime-dependent fraction degree of saturation of the bed. This model is parti cularly suited to predicting the performance of fixed-bed adsorbers when th e system requires a long period of time to reach equilibrium or when severa l fixed-bed adsorbers are used in series.