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oil sands
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The Alberta Oil Sands With a focus on the Athabasca By Dave Henderson Table of Contents 1) Introduction 2) History 3) Geology 4) Composition 5) Extraction Processes 6) Effects of Kyoto 7) Bibliography Introduction For hundreds of years the oil sands have been used as a source of energy and a product of bitumen. Oil sands are deposits of bitumen and have been used in a variety of ways such as boat repairing agents by the Native Americans to a major Canadian energy source. Bitumen is a heavy black viscous oil that must be rigorously treated to convert it into an upgraded crude oil before it can be refined into gasoline and diesel fuels. Oil sands, previously known as tar sands comprise the world’s largest sources of bitumen. The two largest deposits are in Alberta and Venezuela. The Alberta deposits comprise one third of the total bitumen. Oil sands are found in three places in Alberta: Athabasca, Peace River and Cold Lake regions. These three areas cover a total area of nearly 141,000 km2. The volume of Alberta oil sands in place is an estimated1.6 trillion barrels with an ultimate potential of 311 billion barrels and a production rate of 645,000 barrels per day . While conventional crude oil flows naturally or is pumped from the ground, oil sands must be mined or recovered using in situ (know as in-place mining). Oil sands recovery processes include extraction and separation systems to remove the bitumen from sand and water. Oil sands currently represent 40% of Alberta's total oil production, and about one-third of all the oil produced in Canada. By 2005, oil sands production is expected to represent 50 per cent of Canada's total crude oil output, and 10% of North American production 1. Mineable bitumen deposits are located near the surface and can be recovered by open-pit mining techniques where retraction methods are economically practical.. About two tones of oil sands must be dug up, moved and processed to produce one barrel of oil. Roughly 75 per cent of the bitumen can be recovered from sand . The recovery of denser heavy oils and the deeply buried bitumen of the oil sands require first the thinning of the oil to make it mobile, then the application of pressure to make it flow2. Recovery methods are usually used for deposits more than 400 meters and consist of cyclic steam stimulation (CSS) and steam-assisted gravity drainage (SAGD). These in-situ recovery methods include thermal injection through vertical or horizontal wells, solvent injection and CO2 methods3. This paper will discuss the Alberta oil sands with a focus on the Athabasca region. It will cover the history, geology, extraction and processing methods, and effects of the Kyoto. History The oil sands have existed for around 135 million years and remained unknown to man until around 260 years ago. They remained undiscovered because of both their burial in sand and because the remoteness of the Athabasca country remained made it greatly unexplored. The Cree and Beaver Indians were the first inhabitants of the Athabasca County and hunted the forests surrounding the Athabasca River. When European settlement began fur trading took place which later led the Europeans to be introduced to the oil sands. The natives used the oil sands as a caulking compound for repairing their birch bark canoes as well as a mosquito repellent by placing the oil sands in fires . In 1719 a Native American placed the first chunk of oil sand in a non-natives hand. This man was named Henry Kelsey and he described the oil sand "that gum or pitch which flows out of the banks of that river." This was the first time the now famous oil sands were mentioned in Canadian history. One hundred years later in 1819 Sir John Richardson a geognostician (science of the earth) came upon the oil sands. He wrote Below this, where the Washacummow (an early name for the Clearwater), in its winding course through the valley, approaches the high- bounding hills, sections of their sides, formed by the ravines which opened into the river, enabled us to observe that they were composed of sand more or less agglutinated by bitumen, which latter hardens into slaggy mineral pitch. This sandy band, form six hundred to eight hundred feet thick, rests immediately upon yellowish-grey limestone containing many bivalve shells and orthoceratites. The dip, where it could be observed, appeared to be northward. The limestone forms the channel of the river throughout and some protions of it decaying more rapidly then others, exhibit more plainly the shells which enter vary largely into its composistion. This description shows how Richardson gave a geologic view of the oil sand as well as observing the paleontology. In 1875 John Macoun, a botanist, was the first white man to follow the outcroppings of the oil sands from north to south 3. Earlier accounts are of voyages down-river but none followed the outcrop from north to south. They sent Macoun on an expedition to examine the rivers draining into Lake Athabasca. He recorded his observation of water naturally washing oil out of the oil sands that is the essence of today's technology for extracting bitumen from oil sands. His main impression was that the "tar" wasn't mixed with mineral-matter, but the tar flowed through it. 4. The Geological Survey of Canada did more exploration of the region and came up with the prediction that under the oil-laden sands flowed a pure petroleum. They thought that a pool of oil had strained the sand beds where they rose out of the ground down river from Fort McMurry3. This theory was proven wrong within 1912 and 1913 when the first 6 wells were drilled and there were no discoveries of these oil pockets. In 1882 Dr Robert Bell established the oil sands as being in the lower Cretaceous and also reported on the possibility of hot water extraction. This hot was not attempted until 1884 by G.C. Hoffman of the Geological Survey of Canada2. He reported that the bitumen separated readily from the sand. In 1920 the Geological Survey of Canada assigned Dr Karl Clark and his associate Sidney M.
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