Patent ID: 7714180

Claim:
A process for removing methane from an olefinic reactor comprising: (i) cracking a hydrocarbon feedstream to produce an olefinic reactor effluent; (i) fractionating the olefinic reactor effluent into a first overhead stream and a first bottoms stream; (ii) feeding at least a portion of the first overhead stream to a first location of an absorber demethanizer; (iii) feeding a C 4 stream to the absorber demethanizer at a second location on the absorber demethanizer above the first location on the absorber demethanizer; (iv) separating methane from the at least a portion of the first overhead stream in the demethanizer; and (vi) removing a stream comprising C 2 -C 4 hydrocarbons from the demethanizer as demethanizer bottoms; wherein at least a portion of the C 4 stream comprises C 4 hydrocarbons that were separated from the first overhead stream.