A numerical model has been developed to simulate the adsorption of chemical species inside different geometries of columns filled with solid adsorbent particles. In this model hydrodynamics, mass transfer and adsorption equilibrium are accounted for. it has been applied at two different scales: at the laboratory scale in order to estimate the impact of the near wall channelling effect inside small columns, and at the industrial scale in order to calculate the equivalent axial dispersion induced by pipes or beams that can be found inside very large adsorption towers. For both applications, hydrodynamics were found to have a strong impact on the adsorption efficiency. These examples demonstrate how the use of computational fluid dynamics proves to be very relevant for process design and scale-up of adsorption columns. (C) 2008 Elsevier B.V. All rights reserved.