Effect of Delayed Coking Pressure on the Yield and Quality of Middle and Heavy Distillates Used as Components of Environmentally Friendly Marine Fuels

This paper includes the problem statement of obtaining environmentally friendly high-viscosity marine fuels, as well as a possible technological solution consisting in sequential oil processing in an atmospheric-vacuum unit, processing of the vacuum residue with or without preliminary deasphalting in a delayed coking unit, and subsequent compounding of middle and heavy distillates from the delayed coking unit with low-sulfur fractions. The research targets were tar and asphalt, which had been obtained from tar in the process of propane deasphalting. These residues were subjected to coking at 500 °C and a pressure of 0.15–0.35 MPa. Physical properties, chemical composition, and quantitative group hydrocarbon and trace-metal compositions (including vanadium and nickel) were determined for the feed and the obtained middle and heavy distillates. The possibility of applying the maximum amount of coking distillates to obtain environmentally friendly compositions of marine fuel with a sulfur content of up to 0.5 wt % was evaluated.