Chemical modification process of heavy residue from FCC slurry oil for producing high-grade paving asphalt

Abstract

Deoiled asphalt (DOA) and fluid catalytic cracking (FCC) slurry oil are the primary by-products during the SDA and FCC process, usually being regarded as wastes for their poor processability. Thus, it is imperative to find a reasonable utilization of these by-products for the current petrochemical industry. In the present work, a FCC slurry oil residue modification unit for the improvement of oil ageing resistance is proposed. The heavy residue obtained from FCC slurry oil is modified as an aromatic-rich soft component for producing the high-grade paving asphalt by blended with DOA. The effect of operation conditions on the penetration ratio of asphalt products are investigated in a laboratory scale, including the reaction temperature, pressure and dosage of modifier. It is found that the penetration ratio of asphalt is mostly affected by the reaction temperature, less is the pressure and modifier content. Afterwards, pilot-scale modification experiments show that the operation conditions of itself is quite close to that of laboratorial test. Similar optimal conditions are also acquired for both tests, including reaction temperature (180 ℃), pressure (2.0 MPa) and modifier content (3.0 wt%). Compared with original asphalt, the penetration ratio of the asphalt product with a constant blending ratio of modified slurry oil residue to DOA particles (1.02) is increased from 0.539 to 0.653. By this means, the quality of asphalt products eventually meets the standard of 70# paving asphalt. Therefore, this work not only provides a high value-added approach for FCC slurry oil residue modification, but makes full use of previously unavailable DOA.