{HEAD ~ The emulsion flow path} is through successive horizontal emulsion preheating, direct heating, {TAIL ~ post} heating and settling zones of the tank while removing vapor from the top of the zones and water from the bottom of the zones 
is through
{ HEAD ~ The emulsion flow path } is through successive horizontal emulsion preheating , direct heating , { TAIL ~ post } heating and settling zones of the tank while removing vapor from the top of the zones and water from the bottom of the zones
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