Direct coking of athabasca tar sand

Yield patterns and product quality have been determined for the direct coking of Athabasca tar sand. Temperature and vapor residence time are the key variables affecting yield; tar sand residence time has a minor impact in yield provided that a minimum contact time is achieved. Yields are not sensitive to the composition of tar sand feed. Yields from direct coking are similar to those from commercial bitumen coking processes; previously reported variations in direct coking yields can be reconciled when liquid product endpoint and coking severity are considered. Coke deposited on the sand is readily burned, producing a flue gas high in SO 2 and particulates, and a free‐flowing sand. The sand settles readily from a slurry and disposal presents no obvious environmental concerns.