D6 Virgin Fuel Oil

D6 is a residual fuel oil — what remains after the lighter, more valuable fractions like diesel and naphtha have been distilled off crude. That residual origin is what gives it a high viscosity relative to distillate fuels, which is why storage tanks and transfer lines carrying D6 typically need heating capability to keep the product pumpable, particularly in the colder parts of the year or at terminals without year-round tropical ambient temperatures.

The fuel’s combination of high energy density and lower cost per BTU than distillate fuels makes it a standing choice for power generation plants and marine bunkering, where engines are built to run on heavier fuel grades. Because bunker demand is concentrated at a small number of major anchorages, D6 storage tends to cluster at bunkering hubs — which is also where cargo turnover, and therefore terminal throughput, tends to be highest.