technoLogies
Originally conceived by Imperial Oil Limited engineer Roger Butler, and proven viable by the Alberta Oil Sands Technology and Research Authority at its Underground Test Facility in the Athabasca region, SAGD has been commercial since 2001 and has changed the dynamics of the industry. The technology was first commercialized by Alberta Energy Company Ltd., which is now Cenovus Energy Inc.
Two parallel horizontal oil wells are drilled in the formation. The upper well injects steam, which heats the heavy oil or bitumen and lowers its viscosity, allowing it to flow down into the lower wellbore, where it is raised to the surface by steam lift, gas lift or downhole pump. SAGD is the reason why in situ oilsands production is expected to surpass mining by 2015.
ELL R W WELL E C DU OR PRO NJECT I ERS
MB
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ERE COV E R UN Y OIL V HEA
CAPRO
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STEAM
STEAM
RISES A
HA MC
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ProVEn TEChnoLogiES
Steam assisted gravity drainage (SAgD)
ND HEA TS BITU
MEN
OIL & W ATER
SOURCE: CONNACHER OIL AND GAS LIMITED
Central processing facility Thermal in situ heavy oil and oilsands production facilities are essentially water processing plants that produce oil or bitumen as a by-product. At the heart of these plants is the central processing facility where water is treated and steam
Utility heating
Natural gas from pipeline Fuel
is generated to be sent to production well pads via above-ground pipelines. The produced water and oil emulsion is returned via pipeline to the central processing facility where water, gas and impurties are removed and oil is sent to market.
STEAM GENERATION
Water with sludge Treated water
WATER WATER TREATMENT TREATMENT
Blowdown
Steam
Produced gas
WELL PADS
Produced gas
Brackish makeup Fresh water makeup
Disposal injection water Produced water
PRODUCTION PROCESSING
Bitumen Produced water Produced sand
Produced sand Dilbit to sales Diluent (condensate diluent)
SOURCE: STATOIL CANADA LTD./JEREMY SEEMAN
he av y oiL & oiL s a nd s guid eB o o k viii
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