Petroleum coke is a carbonaceous material that results from the coking process during upgrading. There are two types of oil sands petroleum coke: fluid coke, produced by Syncrude, and delayed coke, produced by Suncor and most other upgraders. Fluid coke consists of fine particles, whereas delayed coke is coarser; both are smaller than 3 cm. Both types of coke have ash an content of approximately 7% by weight. The sulphur content can vary from 4% to 7% for both types. Oil sands petroleum coke ash is also high in nickel (1.5 wt%) and vanadium (5wt%).
Coke is used as a fuel to create the high temperatures necessary in blast furnaces to make steel. Unlike petroleum coke, there are very tight specifications for this coke: it is important that it have consistent physical properties (stability, strength, size, shape) and chemical properties (ash, sulphur, volatile matter, alkalis, moisture). The most important properties of coke are heating value (determined mainly by carbon content), ash and sulphur contents. Coke with low ash and sulphur contents are worth more. Typically coking coal must be bigger than 3 cm in size and have an ash content less than 10%.
The differences between the two types of cokes make it technically difficult to use petroleum coke for the same purposes as conventional coke.