Die Bodenkultur - Journal for Land Management, Food and Environment

H. Schachner, M. Rassinger, W. Loiskandl, E. Schäfer and A. Weingartner:

Mathematical description of the simulation model HAM (Hydrodynamic Adsorption Model)


With the introduction of a new operation procedure foran activated carbon 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 (continuos, selective removal, variable flow velocity, activated carbon adsorption) is to support the selective removal of micro pollutants, hence reducing the adsorption of the harmless natural organic matter. A satisfying optimisation of the method is achived with the help of a mathematical model (HAM, hydrodynamic adsorption model). The mathematical model describes the time and space dependent concentration changes of desolved chemicals in a filter column, the concentration at the adsorber surface leading to the loading of the adsorber and the breakthrough curves. The mechanisms considered are convection in the liquid phase, the transition of the dissolved chemicals from the liquid phase to the adsorbed phase through the film covering the carbon particle, the actual adsorption utiIising the ideal adsorbed solution theory (lAST) and the transport of the adsorbent into the particle by surface diffusion. HAM is a physically based model, chemical reactions of substances due to small concentrations are neglected.

Key words:  Activated carbon adsorption, water treatment, adsorption simulation, micro pollutants, selective adsorption.