Patent ID: 11906244
Assignee: UOP LLC
Field: Chemical engineering (Chemistry)
Classification: CPC F | IPC F

Claim 0:
1. A process for separating a feed gas into a volatile residue gas fraction and a less volatile fraction, said feed gas containing hydrocarbons, methane and C2 components together comprising said feed gas, wherein
a. said feed gas is cooled under pressure to form. a liquid stream under pressure and a vapor stream under pressure;
b. said vapor stream is divided to form a first stream and a second stream;
c. said first stream is expanded to a lower pressure to form an expanded first stream, whereupon said expanded first stream is supplied to a distillation column at a mid-column feed position;
d. said second stream is cooled to condensation and expanded to said lower pressure to form an expanded cooled second stream;
e. said liquid stream is cooled to form a subcooled liquid stream, and said suhcooled liquid stream is divided into a first portion and a second portion;
f. said first portion is expanded to said lower pressure and heated to form a heated expanded first portion, thereby to supply at least a portion of said cooling in step e, whereupon said heated expanded first portion is supplied to said distillation column at a lower mid-column feed position;
g. said second portion is expanded to said lower pressure to form an expanded second portion;
h. said expanded cooled second stream is combined with said expanded second portion to form a combined stream, whereupon said combined stream is supplied to said distillation column at a top feed position;
i. said combined stream, said expanded first stream, and said heated expanded first portion are fractionated in said distillation column at said lower pressure to form a distillation vapor stream and said less volatile fraction;
j. said distillation. vapor stream is heated to form said volatile, residue gas fraction, thereby to supply at least portion of said cooling in steps a and d; and
k. the quantities and temperatures of said feed streams to said distillation column are effective to maintain the overhead temperature of said distillation column at a temperature whereby said C2 components are recovered in said less volatile fraction.