A reactor enclosed in {HEAD ~ a pressure vessel} in a manner that the walls of the pressure vessel are thermally insulated and chemically isolated from {TAIL ~ the harsh environment} of the reaction zone in the reactor 
A reactor enclosed in { HEAD ~ a pressure vessel } in a manner that the walls of the pressure vessel are thermally insulated and chemically isolated from { TAIL ~ the harsh environment } of the reaction zone in the reactor
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH