Process for devolatilizing natural gas liquids

Claim 1

A process comprising: retrofitting an existing natural gas separation process to obtain a retrofitted process for separating a natural gas feed selected from a broad range of compositions into a methane-rich gas product and a partially deethanized natural gas liquid product, said retrofitted process including the steps of: (a) dividing said natural gas feed into a first stream and a second stream, the two streams having the same composition; (b) reducing the temperature and pressure of said first and second streams such that each said stream has a distinct liquid phase and a distinct gas phase, said first stream has a temperature substantially lower than said second stream, and at least said first stream has a cryogenic temperature; (c) feeding said first stream into the upper portion of a demethanizing absorption means and said second stream into the lower portion of said absorption means; (d) recovering said methane-rich gas product from the top of said absorption means and a methane-lean natural gas liquid from the bottom of said absorption means; (e) feeding said methane-lean natural gas liquid into a deethanizer means wherein an uncondensed vapor comprised of a portion of the ethane and substantially all of the methane in said methane-lean natural gas liquid is separated from said methane-lean natural gas liquid at a non-cryogenic temperature; (f) recovering said uncondensed vapor from the top of said deethanizer means and recycling said vapor into said second stream of step (c) prior to feeding said second stream into said absorption means; and (g) recovering said partially deethanized natural gas liquid product from the bottom of said deethanizer means comprised of the remaining portion of ethane and heavier hydrocarbons in said methane-lean natural gas liquid and which is less volatile than said methane-lean natural gas liquid.