Abstract: After the start-up of ebullated-bed residue hydrocracking (H-oil) unit, the raw materials of solvent deasphalting unit were adjusted from washing oil of vacuum distillate unit and vacuum residue to unconverted oil from H-oil unit, the properties of deasphalted oil（DAO）were changed. Through process optimization, DAO was stopped blending 2.0 Mt/a VGO hydrotreating unit feed, and it was changed into the feed of residue fluid catalytic cracking unit directly. The operating parameters of VGO hydrotreating unit, the properties of feedstocks and products, and the presure difference of the hydrotreating reactor bed were compared and analyzed before and after stopping blending DAO. The results showed that the feedstocks and products properties, impurities such assulfur and nitrogen removal ratesand hydrotreating reactor bed pressure difference were improved significantly when DAO stopping into VGO hydrotreating unit, meanwhile the unit long-term operation length were extended.

Key words: vacuum gas oil hydrotreating, solvent deasphalting, deasphalted oil, ebullated-bed residue hydrocracking, bed pressure difference