Recycle streams of hydrocarbons and CO2 for the thermal cracking can contribute to savings and {HEAD ~ more efficient use} of {TAIL ~ the feedstock} 
of
Recycle streams of hydrocarbons and CO2 for the thermal cracking can contribute to savings and { HEAD ~ more efficient use } of { TAIL ~ the feedstock }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL