process for recovering processing liquids from a feed mixture

摘要

The continuous process for recovering a processing liquid from a feed mixture comprises: a) introducing the feed mixture into a first heating zone and initially heating the feed mixture to a temperature sufficient to volatilize at least some of the more volatile components and at least a portion of the processing liquid while maintaining the temperature below the decomposition temperature of the processing liquid to produce a vapor stream containing the more volatile component and the vaporized portion of the processing liquid and a residuum; b) the vapor stream is then separated from the residuum in a first separation zone to produce a separated residuum; c) a portion of the separated residuum is passed through a second heating zone at a temperature below the decomposition temperature of the processing liquid to produce a first heated recycle stream; d) the heated recycle stream being admixed with the feed mixture to effect the initial heating of the feed mixture; e) a second portion of the separated residuum is passed through a solids/liquids separation zone to remove any solids present in the second portion of the separated residuum and produce a substantially solids free second recycle stream which is recycled to the first separation zone; f) recovering the processing liquid present in the vapor stream for further use. The feed mixture contains the processing liquid and at least one component that are more volatile than the processing liquid and at least one component that is less volatile than the processing liquid. The residuum of step a) contains the processing liquid, a reduced concentration of the more volatile components and the less volatile components.