Patent ID: 6171449
Filing Date: 2001-01-09
Classification: B01D,C07C,Y10S

Abstract:
An apparatus for the distillation separation of a first hydrocarbon compound from a hydrocarbon mixture consisting essentially of said first hydrocarbon compound and a second hydrocarbon compound, the boiling points of which are so close as to make separation by fractional distillation difficult, said apparatus comprising:(a) first and second distillation column means, each for distilling respectively first and second portions of said hydrocarbon mixture under different pressure and temperature conditions, wherein one of said distillation column means comprises a higher-pressure distillation column and an associated thermal energy source and the other distillation column means comprises a lower-pressure distillation column and an associated thermal energy source;(b) a T-junction splitter for splitting a stream of said hydrocarbon mixture into said first and second portions, said first and second portions being of identical composition and temperature;(c) first and second conduits for conveying respectively said first and second portions respectively to the distillation columns of said first and second distillation column means;(d) a third conduit for conveying a higher-pressure distillation column overhead stream withdrawn from an upper region of the higher-pressure distillation column to a thermal exchange location;(e) thermal exchange means at said thermal exchange location whereby said higher-pressure distillation column overhead stream is brought into thermal exchange with a lower-pressure distillation column bottoms stream withdrawn from a lower region of the lower-pressure distillation column so as to produce a heated lower-pressure distillation column bottoms stream; and,(f) means for returning said heated lower-pressure distillation column bottoms stream to the lower-pressure distillation column.