Optimization of vacuum resid solvent deasphalting to produce bright stock and hard asphalt

ABSTRACT

To prepare bright stock (BS) and 30# hard asphalt simultaneously, propane solvent deasphalting (SDA) of Oman vacuum residue was optimized. Result showed the optimal process conditions were as follows: extraction tower top temperature of 64°C, settling tower top temperature of 74°C, extraction pressure of 3.35 MPa, solvent ratio of 5. Compared with SDA of Oman VR to prepare bright stock and 70# asphalt, the yields of light deasphalted oil (LDAO) and heavy deasphalted oil (HDAO) were 26.8% and 24.7%, and increased by 1.7% and 5.2% respectively; carbon residue of LDAO was less than 1.2%, conformed to the feed requirement of furfural refining to produce bright stock. The yield of DOA was 48.5%, and DOA could be directly used to produce 30# hard asphalt. The PG grade of 30# asphalt was PG 76–22 and the 30# asphalt mixture had high rut dynamic stability and water resistant stability. HDAO could be used as feedstock of catalytic cracking and light yield oil (gasoline and diesel) was 65.99%.

KEYWORDS:

• vacuum residue
• solvent deasphalting
• bright stock
• hard asphalt
• catalytic cracking performance