Patent ID: 9266803
Filing Date: 2016-02-23
CPC Classification: B01D,C07C

Claim Text:
1. A process for separating a liquid feed mixture of two or more solvents in which one solvent (“A”) predominates with other dilute solvent present at concentrations less than 50 mole %, said process comprising the steps of: a. introducing a flow of a liquid feed mixture stream at the top of a vapor stripping column wherein the stripping column additionally contains a rising vapor phase, said vapor stripping column also containing devices inside the column which establish mass transfer surfaces for the interaction of vapor phase and liquid feed mixture streams whereby there is produced a bottoms liquid stream depleted in the more dilute compound and an overhead vapor stream, b. increasing the pressure of said overhead vapor stream using a mechanical overhead vapor compression device to produce a compressed vapor stream; c. passing the compressed vapor stream to a vapor permeation membrane system, the membrane system comprising: at least one permselective membrane having a feed side and a permeate side wherein the feed side of the permselective membrane is in contact with the compressed vapor stream and the permeate side of the permselective membrane is in contact with a vapor at a pressure reduced relative to that of the feed side; d. withdrawing from the permeate side of the membrane system a permeate vapor stream enriched in solvent “A” relative to the compressed vapor stream which was passed on to the feed side of the membrane, e. withdrawing from the feed side a retentate, non-permeated, vapor depleted in solvent “A”, f. introducing at least a portion of the permeate vapor stream withdrawn in step d into the stripping column at the base of the stripping column, wherein a portion of sensible heat in the bottoms liquid stream of step a is transferred to the liquid feed mixture using a heat exchanger.