Process for the recovery and purification of ethylene

Patent · Tue Jan 19 04:00:00 EST 1988

OSTI ID:5417008

Rowles, H C; Grassi, K S; Bernhard, D P

This patent describes a process for the recovery and purification of ethylene from an ethylene containing feed stream, wherein the ethylene containing feed stream is cooled in two heat exchange stages to condense out the bulk of C/sub 2/+ material present in the feed stream; the condensed C/sub 2/+ material is fed to a demethanizer column to remove any remaining light gases, producing a light gas stream as an overhead of the demethanizer column and a demthanized C/sub 2/+ stream is then fed to an ethylene-ethane separation process which produces at least an ethylene product stream and an ethane byproduct stream. The improvement comprises the utilization of three integrated refrigeration cycles wherein low level refrigeration for the second heat exchange stage is provided by work expression, in one or more stages, of at least a portion of an uncondensed light gas stream removed from the cold end of the second heat exchange stage of an uncondensed light gas stream removed from the cold end of the second heat exchange stage and at least a portion of the light gas stream from the overhead of the demathanizer column; intermediate level refrigeration for the demethanizer column condenser and for the cold end of the first heat exchange byproduct stream from the ethylene-ethane separation process with at least a portion of the light gas stream from the cold end of the second heat exchange state or at least a portion of the light gas stream from the overhead of the demethanizer column, or both; and high level refrigeration for the warm end of the first heat exchange stage is provided by a mixed refrigerant system.

• Assignee: Air Products and Chemicals, Inc., Allentown, PA
• Patent Number(s): US 4720293
• OSTI ID: 5417008
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKANES
ALKENES
COOLING
ETHANE
ETHYLENE
EVAPORATION
HEAT EXCHANGERS
HYDROCARBONS
METHANE
ORGANIC COMPOUNDS
PHASE TRANSFORMATIONS
PURIFICATION
RECOVERY
REFRIGERATION
REMOVAL
SEPARATION EQUIPMENT
SEPARATION PROCESSES