Extraction

Separating the bitumen from the sand is the primary objective of Extraction.  Bitumen is extracted from the oil sand at both our Mildred Lake and Aurora sites.

Oil sand, oil sand slurry from the North mine and Aurora froth are all processed at our Mildred Lake facilities:

• Oil sand is fed into tumblers where steam, hot water and caustic soda are added to form a slurry and condition it for bitumen separation.
• Aurora froth mixes with this slurry in the tumblers, and then the combined slurry is discharged onto vibrating screens where large material is rejected.
• This feed is blended with the oil sand slurry from the North mine hydrotransport system.
• The blended slurry is fed into four Primary Separation Vessels (PSVs) and two Auxiliary Settling Areas (ASAs). The bitumen primary froth floats to the top, the sand settles to the bottom, and middlings are pumped to Tailings Oil Recovery (TOR) vessels.
• Froth from the TOR vessels is recycled through the PSVs to improve its quality.
• Bitumen recovered from TOR vessel middlings is processed by a secondary flotation plant, and then combined with the PSV’s primary froth.
• The feed is then deaerated, heated and fed into the Froth Treatment Plant.

At Aurora, oil sand slurry is hydrotransported three kilometres to PSVs, during which time it has already been conditioned for bitumen separation, eliminating the need for tumblers. The froth then travels 35 kilometres via pipeline to the Mildred Lake operation for froth cleaning, treatment and bitumen upgrading.