Distillation: Energy Savings and Other Benefits From the Use of High Efficiency Packings

A great deal of attention has been focused lately on the use of high-efficiency packings for distillation applications. This paper discusses benefits that can be derived from the use of these devices. In particular, the reduction in energy requirements for a given separation is addressed for both new and retrofit applications. Pressure loss and product decomposition are also considered, and the basis for an alternative analysis is established. An example is shown in which an existing distillation tray column is retrofitted with a high-efficiency packing. The process advantages achieved, including energy savings, are discussed, as well as the factors governing the selection of the packing. The current limitations on design models for high-efficiency packings with respect to mass transfer efficiency, pressure drop, and capacity in distillation are mentioned briefly. Finally, the applications of these devices to alternative technologies such as liquid-liquid extraction are discussed