A Comparative study on hydrocracking and hydrovisbreaking combination for heavy vacuum residue conversion

The results of the two successive running hydrovisbreaking-hydrocracking processes (i.e. combination) had relaxed reaction conditions, high HVR conversion and higher HDS reaction compared to hydrocracking process. The combination process characterized with liquid distillates of low sulfur contents, high middle distillates yield, and long catalyst regeneration period. In addition, the remaining heaviest residue fraction, i.e. 350°+, represents either boiler fuel feedstock or a heavier product used as feedstock for other conversion processes (catalytic cracking or delayed coking) due to its acceptable quality. Comparison of hydrodesulfurization (HDS) under hydrocracking and successive hydrovisbreaking/hydrocracking-combination processes at variable reaction temperatures.