An experimental study on optimization utilization of deasphalted oil

As the crude oil reserves become depleted and of deteriorating quality, maximizing the economy of refining plant is increasingly difficult. In the present work, an additional unit of liquid–liquid extraction with deasphalted oil (DAO) as feedstock was proposed to modify the current solvent deasphalting process, for the purposes of improving the quality of deasphalted oil and providing aromatic-rich compounds to blend asphalt. It is important to select a suitable solvent to perform this proposed liquid–liquid extraction process with the aims of improving the quality of FCC feedstock from DAO and supplying aromatic-rich for asphalt-blending. A set of comparative experiments was conducted to observe the extraction performance of five kinds of solvents widely-used in industry. N-methylpyrrolidone was found to perform best with regards to both the yield and the quality of extract. Investigation on operation conditions illustrated that higher temperature facilitated an increase of extract yield at expense of its quality loss. More solvent usage would enhance the raffinate's quality.