Distn. process with variable reflux - having vapour removal from enrichment zone to heaters in stripping zone

摘要

Sepn. of mixts. is carried out in two stage process by distn. At least part of the vapour generated in the enrichment zone is removed and condensed inside heaters located in the stripping zone. This has the effect of increasing the reflux in the enrichment zone and at the same time increasing the vapour flow in the stripping zone. The enrichment or first zone operates at a higher pressure than the stripping or second zone. This second zone should be at a higher geodetic level than the first to allow gravity return of condensed liq. In practice a pair of columns is used with vapour extrn. from between trays on the first and heat exchange coils on the trays in the second. Provides improved sepn. for reduced energy consumption esp. in cryogenic systems.