A first portion of heavy oil or {HEAD ~ another feedstock} can be deasphalted using {TAIL ~ propane deasphalting} or another suitable deasphalting process 
A first portion of heavy oil or { HEAD ~ another feedstock } can be deasphalted using { TAIL ~ propane deasphalting } or another suitable deasphalting process
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH