Further release of gas and {HEAD ~ stratification} of the oil and water occurs within {TAIL ~ the post heating zone} 32 
occurs within
Further release of gas and { HEAD ~ stratification } of the oil and water occurs within { TAIL ~ the post heating zone } 32
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH