Patent ID: 8916740

Claim:
A distillation process comprising two or more xylene columns separating C8-aromatics streams from C9-and-heavier aromatics streams contained in at least one higher-boiling and at least one lower-boiling feed stream, comprising: (a) distilling at least one higher-boiling feed stream in at least one first low-pressure xylene column to separate a first C8-aromatics stream from a first C9-and-heavier aromatics stream; (b) distilling at least one lower-boiling feed stream in at least one second xylene column at an elevated pressure above the low pressure to separate a second C8-aromatics stream from a second C9-and-heavier aromatics stream, wherein the at least one higher-boiling feed stream has a higher content of C9-and-heavier aromatics than the at least one lower-boiling feed stream; and (c) condensing an overhead stream from the at least one second xylene column by exchanging heat with one or more of a reboiler of the at least one first low-pressure xylene column and a steam generator.