Simplified Models for Design of Fixed‐Bed Adsorption Systems

Abstract
Fixed‐bed adsorber dynamics have been predicted successfully using the homogeneous surface diffusion model (HSDM) for over 100 adsorbate‐adsorbent systems which include a number of the possibly harmful organics that may be found in drinking water and wastewater. Solutions to the HSDM for fixed‐bed adsorber systems have been developed and can be used to: (1) Plan the scope of pilot‐scale studies by identifying least‐cost fixed‐bed adsorber operations; (2) interpret pilot‐scale test results; and (3) design full‐scale adsorbers if the HSDM can simulate pilot‐scale data. To facilitate the use of these solutions, the important model parameters and their effect on adsorber performance has been discussed; additionally, a detailed procedure for determining the effluent concentration history profile has been presented. Techniques to calculate the empty bed contact time of the mass transfer zone and the liquidand solid‐phase concentrations within the fixed bed have also been provided.