Canada's oil sands are recovered using
two main methods: drilling and mining.
About 20% of the resource known as
bitumen is found within 70 metres of the
earth's surface. These reserves, a mixture
of bitumen and sand, are shallow and can
be recovered through mining. Only 3% of
the oil sands' total surface area can be
mined. Oil sands mining is a three-stage
process - mining, extraction and tailings
management. Typically in mining
operations the oil sands are scooped up
by large shovels and loaded into heavy
haul trucks. The trucks deliver their
load to a crusher which breaks down the
large clumps of bitumen and sand in
preparation for transport. There are
several methods of transport. One is
hydro transport. Water is added and this
mixture is sent to the extraction
facility by pipeline. During extraction
the mixture is fed into an extraction
vessel to be treated. Hot water is added,
which helps separate the bitumen from
the sand. Gravity pulls the sand to the
bottom of the vessel while the bitumen
floats. Sometimes the bitumen goes
through a second separation process to
improve the quality. The bitumen is
removed as a froth and is now ready to
be moved to an upgrader or sent via
pipeline for export. Meanwhile the
mixture of sand and water at the bottom
of the extraction vessel, also called
tailings, is transferred to tailings
ponds to settle and separate. As the
solids settle out the water on top is
sent back to the mine to be heated and
used again in extraction. Recycling water
in this way reduces the amount of water
needed for mining operations. All lands disturbed by oil
sands mining operations, including
tailings ponds, will be reclaimed to a
self-sustaining landscape. Bitumen is a
valuable resource that can be refined
into transportation fuels such as
gasoline, diesel, and jet fuel. It can also
be used by petrochemical plants to
create everyday products like cosmetics,
textiles, plastics, and lightweight
construction materials.
