{HEAD ~ Processing aids} to improve {TAIL ~ the bitumen recovery} and froth quality in oil sands extraction processes 
to improve
{ HEAD ~ Processing aids } to improve { TAIL ~ the bitumen recovery } and froth quality in oil sands extraction processes
HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH