Industrial & Engineering Chemistry Research, Vol.60, No.1, 652-658, 2021
Study on Solvent Deasphalting Process for Upgrading of Hydrocracking Unconverted Oil
Ebullating bed hydrocracking (EBH) and solvent deasphalting (SDA) process are effective pretreatment upgrading technologies for vacuum residuum (VR). In this work, the SDA performance of EBH unconverted oil (UCO) was investigated and the optimum process conditions were found to obtain the right balance between the maximum yield and the best properties of deasphalted oil (DAO). The test results showed that the change in operating conditions had a more significant impact on mass balance than on product quality in most cases. Compared with pressure and solvent-to-feed ratio, temperature had a more significant effect on mass balance. The yield of DAO could be significantly increased by decreasing the extraction temperature in the subcritical temperature range, while the properties of DAO did not deteriorate. Under the optimal operating conditions (temperature, 130 degrees C; pressure, 4 MPa; S/F ratio, 4.5), the yield of DAO was 68.89 wt % and the properties of DAO had been significantly improved compared with UCO. Simultaneously, deoiled asphalt (DOA) had good high-temperature performance and could be employed as a widely used asphalt-blending component. The combined process of EBH and SDA, an integrated process of refining and chemical, is an effective upgrading technology for high-sulfur and high-carbon-residue vacuum residuum.