Patent ID: 7107788

Claim:
A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons into a volatile gas fraction containing substantially all the methane and a less volatile hydrocarbon fraction containing a large portion of the C2+ components, the process comprising the steps of: (a) splitting an inlet gas stream into a first feed stream and a second feed stream and cooling the first and the second feed streams; (b) supplying a top of a packed bed cold absorber with the first feed stream and a bottom of the tower with the second feed stream where the first feed stream has a temperature colder than the second feed stream, the absorber comprising at least a first and a second packed bed and producing an absorber overhead stream, an absorber bottoms stream, and an absorber side draw stream; (c) removing the absorber side draw stream from the packed bed cold absorber; (d) cooling and at least partially condensing the absorber side draw stream to form a first fractionation tower feed stream; (e) expanding and then supplying a fractionation tower with the absorber overhead stream as a second fractionation tower feed stream; (f) supplying the fractionation tower with the absorber bottoms stream as a third fractionation tower feed stream; (g) separating the first fractionation tower feed stream, the second fractionation tower feed stream, the third fractionation tower feed stream and a tower reflux stream to produce a fractionation tower overhead stream that contains substantially all the methane and lighter components and a fractionation tower bottoms stream that contains substantially all the C2+ components; (h) warming and compressing the fractionation tower overhead stream to produce a residue gas stream; (i) removing at least a portion of the residue gas stream as the fractionation tower reflux stream; (j) cooling and supplying the fractionation tower reflux stream to the fractionation tower as a residue recycle stream; and (k) supplying the fractionation tower with the first fractionation tower feed stream thereby reducing an amount of the residue gas being compressed and an amount of the residue recycle gas being sent to the fractionation tower.