Process for recovery and purification of C/sub 3/-C/sub 4+/ hydrocarbons using segregated phase separation and dephlegmation

Patent · Tue Dec 22 00:00:00 EST 1987

OSTI ID:5450264

Rowles, H C

A process for the low temperature separation of a feed gas into a heavy hydrocarbon stream containing C/sub 3+/ and/or C/sub 4+/ hydrocarbons and a light gas stream containing H/sub 2/, N/sub 2/, CO, CO/sub 2/, methane, and/or C/sub 2/ hydrocarbons is described comprising the steps of: (a) cooling the feed gas to effect the partial condensation of the gas by indirect heat exchange against process streams; (b) initially phase separating the partially condensed feed gas into a first heavy liquid stream containing heavy hydrocarbons and a first vapor stream containing light feed gas components; (c) rectifying the first vapor stream by low temperature dephlegmation to produce a first light gas stream and a second heavy liquid stream which is segregated from the first heavy liquid stream wherein the first vapor stream is cooled in the dephlegmation by indirect heat exchange with the first light gas stream which is expanded to a lower temperature and pressure; (d) expanding the first and second heavy liquid streams to a lower pressure and temperature and cooling the feed gas with one or both of the streams by indirect heat exchange sufficiently to partially vaporize the stream(s) as process streams of step (a); (e) separately introducing the first and second heavy streams into a distillation column operated with an overhead condenser and a bottom reboiler; (f) separating the streams in the distillation column into a heavy hydrocarbon stream C/sub 3+/ and/or C/sub 4+/ hydrocarbons as a bottom product and a second light gas stream; and (g) recovering the first light gas stream and the second light gas stream to produce one or more product light gas stream() containing H/sub 2/, N/sub 2/, CO, CO/sub 2/, methane, and/or C/sub 2/ hydrocarbons.

• Assignee: Air Products and Chemicals, Inc., Allentown, PA
• Patent Number(s): US 4714487
• OSTI ID: 5450264
• Resource Relation: Patent File Date: Filed date 23 May 1986
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
HYDROCARBONS
DISTILLATION
PURIFICATION
RECOVERY
SEPARATION PROCESSES
CARBON DIOXIDE
CARBON MONOXIDE
HYDROGEN
METHANE
NITROGEN
PROCESSING
TEMPERATURE EFFECTS
ALKANES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
ELEMENTS
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
400201* - Chemical & Physicochemical Properties