{HEAD ~ A method} 1 operated as {TAIL ~ a continuous process} with metal oxide being provided to the crucible and recovered metal being collected at the lip 
operated as
{ HEAD ~ A method } 1 operated as { TAIL ~ a continuous process } with metal oxide being provided to the crucible and recovered metal being collected at the lip
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH