Water Quality Management for Oil Sands Extraction
The Water Quality Management for Oil Sands Extraction is a partnership between Alberta Innovates Energy and Environment Solutions (AIEES), Kemira Oil & Gas/Kemira Water Solutions (Canada) Ltd., Suncor Energy Services Inc., Statoil Canada Ltd., ConocoPhillips Canada, and the University of Alberta.
The research undertaken aims toward fundamental studies that can provide pathways for sustainable management of the freshwater resources during oil sands extraction. The immediate focus of the research program is management of produced water quality during in-situ oil sands extraction, particularly employing the steam assisted gravity drainage (SAGD) process.
Schematic of a SAGD process (courtesy: Suncor Energy).
A pair of horizontal wells is drilled underground into the oil sands bearing stratum. Steam is injected into the formation through the upper well, which heats up the bitumen. Heated bitumen becomes less viscous and flows under the influence of gravity into the lower well. The liquefied hot bitumen is pumped out of this lower well along with the condensed water. The process involves use of saturated steam at around 550 psi pressure.
SAGD plants are often considered as water treatment plants with bitumen as a by-product. Considerable expense is involved in treating the produced water that is extracted along with the bitumen to produce a sufficiently clean feed water for the steam generator. The steam is again fed back into the oil bearing reservoir.
- Alberta has over 2 trillion barrels of heavy oil and bitumen, of which 175 – 315 billion barrels are currently recoverable.
- Only about 20% of this recoverable reserve is explored using mining techniques, whereas nearly 80% of the reserve can only be accessed using in-situ technologies.
- One of the in-situ recovery methods is Steam Assisted Gravity Drainage (SAGD).
- Each barrel of bitumen produced by SAGD requires about 3.0 bbls of water, over 90% of which is recycled (thus requiring only about 0.1- 0.2 bbl of freshwater).
- Assuming production of a bitumen plant is 100,000 barrels of bitumen per day, the water treatment requirement of the plant is about 300,000 bpd (~12.6 Million Gallons per Day, MGD).
Please click on the logos of the partner organizations, and you will be taken to their homepages (in a separate window).
|Statoil Canada Ltd.|