| 摘要 |
PURPOSE:To recover crude benzene, etc., at reduced costs of heat energy, construction of equipment, etc., by removing benzene and water from a specified raw material oil in a benzene removing tower and passing it through a naphthalene removing tower, etc., for stripping. CONSTITUTION:A raw material oil which contains benzene, naphthalene, etc., is sent from a receiving tank V-1 to a benzene removing tower C-1 for simultaneous steam stripping and dehydration treatment with steam blown into the tower from the bottom. A middle layer fraction in the tower C-1 is extracted and heated in a heating oven F-1 under reflux and a benzene-free oil is extracted for discharge from the system. A part of the oil in a required amt. is sent through a heat exchanger E-3 to a naphthalene removing tower C-2 for removal of naphthalene by steam distillation. A part of distillate is heated under reflux and is extracted from the system with a pump P-4. Steam is blown from the bottom into a depitching tower C-3 connected to the lower part of the tower C-2 to perform stripping and a pitch oil is extracted from the bottom. Tower top gas of the tower C-2 is fed into the tower C-1 for recovery of crude benzene and crude naphthalene.
|
