Production
Technologies
In-situ projects
need to somehow generate the steam that loosens the bitumen. Current projects
use boilers fired by enormous amounts of natural gas, a process that uses a lot of waterthe
equivalent of three cubic metres for each cubic metre of bitumen produced.
However, more than 80 percent of the water used is able to be recycled and used
again (the remaining 20 percent remains in the reservoir). After the bitumen is
separated from the sand and water, it is shipped by pipeline to a refinery or an
upgrader.
In-situ
production is able to recover between 25 and 75 percent of the bitumen found in
the reservoir, which is a higher recovery percentage than that of most
conventional light crude wells. However, scientists continue to look for a way
to improve these percentages. In-situ bitumen recovery is more attractive than
mining because it disturbs considerably less land and requires less
land-reclamation activities once the project is finished and all the
trucks leave.
New technologies
are constantly being developed in the area of bitumen recovery, and other in-situ production systems
have been tested for accuracy and cost-effectiveness. Solvents, microwaves, and
ultrasound have all been experimented with. "Fireflooding" is another
experimental production technique where air or oxygen is injected into the
formation and the bitumen ignited in order to heat the oil sand. However,
only solvents have moderately stood the test of timeall other experimental
technologies have been more or less abandoned. Cyclic steam stimulation (CSS)
and SteamAssisted gravity drainage (SAGD) are the most often used technologies
today.
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