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For many years, trying to
tap an oil sands deposit accomplished about as much as sipping molasses
through a straw, but that is changing. So do oil sands companies make a good
investment now?
Humans and bacteria share a
surprising number of features, not least in what they consider good food. In
general, the smaller and simpler the molecule, the easier it is to digest.
So, about 50 million years ago, when and where bacteria had a chance to chow
down on some of the rich hydrocarbons we call oil, one might expect them to
start on the smaller, tidier mouthfuls, and indeed they did.
What's left today of these
bacterial banquets are deposits of oil molecules so big and cumbersome that
they flow like molasses in winter, if at all. At the extreme end is bitumen,
which looks rather like sticky asphalt:

The oil sands that contain this
heavy oil and bitumen have long posed an intriguing "what-if" for
the industry. heir potential is staggering. One of
the world's largest deposits, in the Canadian province of Alberta, spreads
over the size of Wisconsin and may hold two trillion barrels of oil -
eight times the reserves of Saudi Arabia.
For just about as long,
however, oil sands have been minor players at best in the world's energy
picture. The very qualities that native peoples have exploited to seal their
boats make these heavy oils and bitumen tough to suck out of the ground and
shove down a pipeline. And that's before they even get to a refinery.
Two developments in recent
years have brought oil sands in from the cold: rising oil prices and new
technology to pry bitumen out of deposits and make it run, not walk, to the
nearest processing facility.
So let's take a look at how oil
sands came about and what we can do with them.
The Tale of Two Oil Deposits
We're back to millions of years
ago, this time to the hundreds of millions, when algae and the simple
organisms that fed on them died, drifted down to the seafloor, and were
gradually buried under sediments and subsequent generations of ancient life.
As the ages passed, the
pressure of layers above and heat from inside the earth broke down and
reassembled these simple plants and animals into chains of carbon atoms
bristling with hydrogen. Under pressure, these hydrocarbons squeezed through
grainy, porous sedimentary rock until blocked by nonporous rock, known as
capstone. There accumulated the first of our tale, a deposit of what we now
call conventional oil.
The other deposit was in for a
second ride. Geological forces lifted these oil-bearing rocks up toward the
surface of the earth, within reach of water and bacteria. You know what
happened next.
Because of this additional
history, oil sands differ in structure as well as content from conventional
oil deposits. The bitumen coats the grains of sand like a film and is in turn
surrounded by water. Scraping the bitumen off the grains is the first step in
extraction.
The uplifting also means that
oil sands deposits are relatively shallow: some can even be surface-mined
like coal.
This geological process
happened in places like Venezuela and the United States, and particularly in
Canada. In the province of Alberta are three major oil sands areas: the
Athabasca (the largest), Peace River, and Cold Lake. Current estimates put
the combined bitumen in these deposits at 1.7 trillion barrels, and some
geologists believe more field work will jack that number up a fair bit
further.
The catch is that, at present,
only 10% or 170 billion barrels of that bitumen is considered economically
recoverable, that is, worth a producer's considerable effort to bring it to
market. Even so, 170 billion barrels places Alberta second only to Saudi
Arabia in terms of proven oil reserves, and ever-developing technology is
likely to bring more in reach.
We're going to focus on Alberta
because it's home to the largest and most developed
oil sands deposits in the world.
To Market, to Market: Step 1
Surface mining operations dig
up and crush the oil-soaked rock, then mix it with water heated to
50-80°C. In such conditions, the bitumen floats off. All told, bitumen
recovery from strip mines approaches 90%, and the mining and processing costs
come in at about US$8.00 per barrel.
However, only about 20% of
Alberta's bitumen is shallow enough for surface mining. The remaining 80%
requires drilling and in-situ methods that extract the oil from the rocks in
place. There are several methods to do this, and more in development. What
they generally have in common is pumping down steam to heat the trapped oil,
making it less viscous. Then a producer can actually pump the bitumen to the
surface.

Many oil sands companies use
this in-situ method, called steam-assisted gravity drainage (SAGD).
Another factor in-situ methods
have in common is the large amounts of energy required to generate the steam.
At present that energy usually comes from natural gas, which comprises 65-80%
of total operating costs.
According to government
statistics, Alberta is host to 91 producing oil sands projects as of 2009. Of
these, only four are mining projects, while the remaining 87 use various
in-situ recovery methods. In 2009 those projects produced an average of 1.49
million barrels of bitumen per day (bbpd), which
represents more than 40% of Canada's total oil production. That 1.49-million
figure is projected to reach 3 million bbpd by
2018.
To Market, to Market: Step 2
However it's recovered, this
stiff black glop needs further work in order to sell it. An oil sands
producer has two choices: to upgrade it and make synthetic oil,
or to dilute it with lighter hydrocarbons so it can run down a pipeline to a
refinery.
Upgrading usually requires two
steps. First the bulky hydrocarbon chains are broken into smaller ones in a
process called hydrocracking; upgraders
may also remove carbon to produce the smaller chains along with coke. The
second step adds hydrogen to "fill out" the new carbon chains and
to remove impurities like sulfur. Currently five upgraders
in Alberta churn out a bit over 1 million barrels of synthetic crude oil each
day, and there are plans for more.
Bitumen that's not upgraded is
blended with diluents that make it runny enough to pipe to refineries
throughout North America. The diluents are usually a mixture of light
hydrocarbons, such as light crude oil and naphtha. Companies can recycle
diluents that stay within Alberta, a significant consideration in project
planning.
The investment to get the
industry to this stage has been massive. Between 1999 and 2009, an estimated
$91 billion was pumped into developing Alberta's oil sands. In 2009 industry
invested another $10 billion, and almost $170 billion worth of oil sands
projects are currently underway or proposed in the province.
Environmental Issues
Environmental groups have
labeled bitumen "dirty oil" and are calling for an end to oil sands
operations. They have three main complaints: that ugly mines and tailings
ponds destroy habitat, that projects gulp energy and emit significant
emissions for every barrel of oil, and that the whole process uses a
significant amount of water.
The groups are certainly right
on some fronts. In-situ operations cause minimal disturbance, but surface
mining - even though it represents only 20% of oil sands operations - does
make an unsightly mess of boreal forests and marshlands. And in-situ projects
have their own issues. The roughly 30 cubic meters of natural gas and three
barrels of water consumed to produce one barrel of bitumen are indeed high.
Well, oil sands aren't going
away. Their potential is too vast, global demands for energy too high, and
for governments like Alberta, they contribute too much to the coffers.
But more encouraging yet,
industry is developing less intensive techniques. Quick-drying tailings ponds
can be returned to nature faster, for example. And companies have a double
incentive to develop in-situ methods that require less energy and water: they
would lower operating costs as well as mitigate complaints.
[One of the
current picks of the Casey Energy team is a company that’s proving up
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Marin Katusa
Casey’s Energy Report
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