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