Patent ID: 8635885

Claim:
A method of recovering NGL from a natural gas comprising: cooling and separating an overhead product of a scrub column to produce a C5+ depleted vapor fraction and a first reflux for the scrub column; cooling and separating a first portion of the C5+ depleted vapor fraction to produce a second reflux for the scrub column and a C3+ depleted vapor stream. expanding the C3+ depleted vapor stream in an expansion device to generate refrigeration for the first portion of the C5+ depleted vapor fraction; compressing and combining the expanded C3+ depleted vapor stream with a second portion of the C5+ depleted vapor fraction to thereby form a liquefaction feed stream; and using a ratio between the first and second portions of the C5+ depleted vapor fraction and/or a discharge pressure of the expansion device to control C3 recovery in a bottom product of the scrub column.