An investigation into the gas phase coking tendencies of Athabasca bitumen

The cyclone sections in the top of Syncrude Canada's cokers have been observed to plug off completely with coke during each operational cycle. This work was conducted to determine if gas phase deposition mechanisms could be responsible for the formation of the coke plugs. An experimental system was constructed to determine the effects of adjusting vapour phase temperature and residence time on the resulting gas phase coke yield. The major finding from this study was that raising the temperature of the gas phase above the feed temperature significantly enhanced the formation of gas phase coke. The increased gas phase coke yields were accompanied by increased non-condensable gas yields and reduced liquid product yields. Raising the gas phase temperature also resulted in upgrading of the produced liquid. When the gas phase temperature was raised above the feed temperature the rate of gas phase coke formation was observed to increase.