Abstract: The process of extracting aromatics from depentanizer oil and hydrotreated pyrolysis gasoline units, respectively, mixing the products and then distilling to produce benzene and toluene (named as two head and one tail process) was applied for two aromatics extraction units with 350 kt/a and 700 kt/a in CNOOC Huizhou Petrochemical Co. Ltd.. Based on the actual production data, the process design, raw material compositions, product comprehensive applications, product yields, unit energy consumption, and three reagents consumption for two raw materials were analyzed and compared. The problems in the operation of two sets of extraction units were summarized in order to provide reference for the production management of similar units.

Key words: depentanizer oil, hydrotreated pyrolysis gasoline, aromatics extraction, process design, benzene, toluene, energy consumption