INTERMEDIATE REBOILER AND CONDENSER ARRANGEMENT FOR BINARY DISTILLATION-COLUMNS

The most thermodynamically efficient configuration for adding or remov ing heat from an intermediate location of an ideal binary distillation column distilling pure products is derived The optimal policy require s that preconditioning of the feed be part of the overall decision-mak ing process. The optimal configuration can be determined through the u se of two parameters, alpha(IR) and alpha(IC), that are solely functio ns of feed composition. Simple and readily usable heuristics using the se parameters are developed that help instantly identify the most effi cient selection among (I) totally vaporizing and returning a side-draw liquid stream from an intermediate location of the distillation colum n, (2) partially ol totally vaporizing a portion of the given saturate d liquid feed, (3) partially or totally condensing a portion of the gi ven saturated vapor feed, and (4) totally condensing and returning a s ide-draw vapor stream from an intermediate location of the distillatio n column.