A reactant header 18 is provided at the inlet side 14 of the tube bundle and {HEAD ~ a product header} 20 is provided at {TAIL ~ the outlet side} 16 of the tube bundle 
A reactant header 18 is provided at the inlet side 14 of the tube bundle and { HEAD ~ a product header } 20 is provided at { TAIL ~ the outlet side } 16 of the tube bundle
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH