Abstract: A certain domestic refinery with a capacity of 10-Mt/a faces the problem of insufficient heavy oil processing capacity after the commissioning of the refinery-chemical integration project. Relying on the existing crude oil resources and actual facilities of the refinery, focusing on the heavy oil processing system, implement a comprehensive adjustment of the product structure. After comparing multiple schemes such as the construction of a new delayed coking unit and a new slurry-bed residual oil hydrogenation unit, the benefit calculation results indicate that the liquid yield of the newly constructed delayed coking unit is relatively low, and the price of the petroleum coke produced is also low, leading to lower benefits from adopting this scheme. The construction of the new slurry-bed residual oil hydrogenation unit resolves the issue of insufficient heavy oil processing capacity at the refinery, enabling the entire plant to cease production of heavy oil products such as asphalt and marine fuel oil.At the same time, a new diesel hydrocracking unit was built to treat the diesel of the whole plant, which reduced the diesel product and increased the materials of catalytic reforming, increased the output of p-xylene by 0.1 Mt/a, and increased the output of chemical light oil by more than 0.6 Mt/a, which is in line with the trend of "oil to chemicals" in the petrochemical industry.

Key words: delayed coking, vacuum residue, slurry-bed residue hydrogenation, p-xylene, asphalt, catalytic reforming, diesel hydrocracking, benefit calculation