MATHEMATICAL-DESCRIPTION OF THE SIMULATIO N-MODEL HAM (HYDRODYNAMIC ADSORPTION MODEL)

With the introduction of a new operation procedure for an activated ca rbon filter the demand of a simulation tool to support the laboratory tests has risen. The use of the simulation tool should be extended for design purposes in future. The purpose of the KSVA-procedure (continu os, selective removal, variable flow velocity, activated carbon adsorp tion) is to support the selective removal of micro pollutants, hence r educing the adsorption of the harmless natural organic matter A satisf ying optimisation of the method is achived with the help of a mathemat ical model (HAM, hydrodynamic adsorption model). The mathematical mode l describes the time and space dependent concentration changes of deso lved chemicals in a filter column, the concentration at the adsorber s urface leading to the loading of the adsorber and the breakthrough cur ves. The mechanisms considered are convection in the liquid phase, the transition of the dissolved chemicals from the liquid phase to the ad sorbed phase through the film covering the carbon particle, the actual adsorption utilising the ideal adsorbed solution theory (IAST) and th e transport of the adsorbent into the particle by surface diffusion. H AM is a physically based model, chemical reactions of substances due t o small concentrations are neglected.