Frozen Lump Generation of Oil Sands – Climatic Challenges and Solutions
CIM Edmonton 2004
Dwayne D Tannant, David C Sego, Victor Del Valle Del Valle,
Climate has an immense impact on the properties of Athabasca oil sands and the ease or difficulty with which it is excavated and extracted. During the winter months, frost ingresses into exposed oil sand surfaces freezing the in situ water. When the massive hydraulic and electric shovels used in the various operations in the Fort McMurray area excavate the benches, large frozen lumps are created. These lumps are either destined for a lump dump where increased costs are incurred due to rehandle, or they are sent to the primary crushers where they can cause significant downtimes by jamming the crusher. The crusher down time can sometimes be in the order of hours of lost production.
Studies on data from two consecutive winters in Syncrude Canada’s North Mine show a high correlation between climate and the generation of frozen oil sand lumps. Temperature, ground cover, traffic, bench exposure time, oil sand grade and moisture content all contribute to this problem. A 1D frost penetration model was used to predict the depth of frost expected in oil sands and the corresponding likelihood of frozen oil sands lumps. To combat the challenge of frozen lump generation, a number of proactive and reactive measures can be taken: artificial snow, shallow ponds, blasting and ripping.
Oilsands, Freezing, lumps, Oil sands, Crusher, frost