Fluid Dynamics of Packed ColumnsThe? rstGermanedition of thebookFluiddynamicsofpackedcolumns with modern random and structured packings for gas liquid systems was published in 1991. It sold out within a few years. Added to this were numerous enquiries, in particular within the industry, prompting me to publish a second, extended edition. A packed column remains the core element of any diffusional separation process. This underlines the need for basic design principles for packed