DIR Vacuum Distillation Refining Equipment for used engine oil recycling to produce high quality base oil There are non-hydrocarbon, alkene, polycyclic aromatic hydrocarbon, metal hydronium, impurities, metal particles, asphaltene and colloid etc. harmful materials existed in used oil.These harmful substances are mutually as initiator,providing reagent and catlyst to each other.They’re oxidating, ...