A study conducted for the Alberta government’s research organization has created a framework for developing technologies related to tailing ponds in oil sands mining operations.
The ponds, which hold fluids and solids left over from the initial processing of oil sands, cover large areas. An important environmental goal has been to accelerate tailing-pond cycling times.
The study, done by the Oil Sands Tailings Consortium (OSTC) for Alberta Innovates—Energy and Environment Solutions (AI-EES), identifies nine “roadmaps” for tailings technology deployment:
• Centrifuging mature fine tailings with conveyors and stacking.
• Composite tailings.
• In-line thickening with thin lift evaporative drying.
• Water-capped end-pit lake.
• Improvement to water-based extraction.
• Nonaqueous solvent extraction; retort-based extraction; parallel high-low fines suite.
• In-pit tailings stream.
Each roadmap contains a suite of technologies allowing oil sands operators to convert fluid fine tailings inventory into a deposit ready for reclamation.
One of the study’s conclusions is that “there is still no ‘silver bullet’ tailings technology such as a single technology or suite of technologies which will solve all the oil sands tailings challenges with a single effort.”
The study involved Alberta Energy, Natural Resources Canada, Alberta Environment and Sustainable Resource Development, and the Alberta Energy Resources Conservation Board.
It included a review of more than 500 tailings technologies and related methods.
Members of the OSTC, formed in December 2010, shared their tailings technologies under development. OSTC members are Suncor Energy, Syncrude Canada Ltd., Shell Canada, Canadian Natural Resources Ltd., Imperial Oil, Total E&P Canada, and Teck Resources.