STRUCTURED OF RANDOM PACKINGS - WHERE DOE S THE FUTURE LIE

Over the years a large number of dumped and ordered packings have been developed for effective treatment of material in absorption, desorpti on, extraction and rectification columns. The task of these column pac kings is to improve the mass transfer between a liquid phase and a gas or vapor phase. Furthermore, they also have to assure large throughpu ts at low pressure drops. When elaborating possible solutions for the separation of liquid mixtures or for cleaning flows of waste air or wa ste water in mass transfer columns, the planning engineer repeatedly f aces the question of which dumped packing or which arranged packing pr esents the most favorable design from a process engineering standpoint . In recent years the opinion has often been voiced that arranged pack ings are always more effective than dumped packings. The purpose of th is paper is to show that a number of applications exist in which moder n dumped packings are equal or even superior to arranged packings. On the basis of selected examples the author discusses when the use of a structured packing is preferable with regard to process engineering.