ESL Lesson 1
Oil in Our Every Day Life
ESL Lesson 2
The History of Mining
ESL Lesson 3
Economic growth
ESL Lesson 4
Delivery Systems
ESL Lesson 5
Cities and Population Movement
ESL Lesson 6
Recycling
ESL Lesson 7
Rubber
ESL Lesson 8
Farming
Possible Alternatives to Replace Crude Oil
Tar sands
Tar sands, also referred to as oil sands or bituminous sands, are a combination (mixture)of clay, sand, water, and bitumen. Technically speaking, bitumen is neither oil nor tar, but a semisolid, form of oil which will not flow toward producing wells (pumping oil wells) under normal conditions, making it difficult and expensive to produce. Tar sands are mined to extract (get out) the oil-like bitumen which is upgraded (converted/changed) into synthetic crude oil or refined directly into petroleum (oil) products by specialized (specially built) refineries. Conventional oil is extracted by drilling a well into the ground, but tar sand deposits are mined using strip mining techniques, or persuaded (made) to flow into producing wells by in-situ techniques which reduce the bitumen's viscosity (thickness) with steam and/or solvents.
Location
Tar sands deposits are found in over 70 countries throughout the world, but three quarters (3/4) of the world's reserves are in two regions (areas), Venezuela and Canada. Tar sands have only recently become considered to be a major part of the world's oil reserves, that is, they have become economically extractible at current prices with current technology. To distinguish (identify the difference) the bitumen and synthetic oil extracted from tar sands vs. the free-flowing hydrocarbon mixtures known as crude oil that oil companies have pumped from oil wells, tar sands are often referred to as Non-Conventional Oil. Tar sands represent as much as 66% of the world's total reserves of oil, with at least 1.7 trillion barrels in the Canadian Athabasca Tar Sands and 1.8 trillion barrels in the Venezuelan Orinoco tar sands, compared to 1.75 trillion barrels of conventional oil worldwide, most of it in Saudi Arabia and other Middle-Eastern countries. Between them, the Canadian and Venezuelan deposits contain about 3.6 trillion barrels of oil in place.
Canada
Most of the oil sands of Canada are located in three major deposits in northern Alberta. The three deposits are the Athabasca-Wabiskaw oil sands of north northeastern Alberta, the Cold Lake deposits of east northeastern Alberta, and the Peace River deposits of northwestern Alberta. Between them they cover over 140,000 square kilometers and hold at least 175 billion barrels (175xl09 bbl) or 28 billion cubic meters (28x109 m3) of recoverable (able to mine and produce) crude bitumen, which amounts to three-quarters of North American petroleum reserves. The Alberta oil sands deposits contain at least 85% of the world's total bitumen reserves but are so concentrated (high concentration) as to be the only such deposits that are economically recoverable for conversion (change) to oil are the Athabasca Oil Sands along the Athabasca River. The mineable (able to mine) area as defined (marked) by the Alberta government covers (about 3400 square kilometers or 1300 square miles) north of the city off Fort McMurray. All three Alberta areas are suitable (appropriate) for production using in-situ methods such as cyclic steam stimulation (CSS) and steam assisted gravity drainage (SAGD).
The Canadian oil sands have been in commercial production since the original Great Canadian Oil Sands (now Suncor) mine began operation in 1967. A second mine, operated by the Syncrude consortium (a group of businesses), began operation in 1978 and is the biggest mine of any type in the world. The third mine in the Athabasca Oil Sands, the Albian Sands consortium of Shell Canada, Chevron Corporation and Western Oil Sands Inc. began operation in 2003. However, with the development (invention) of new in-situ production techniques (methods) such as steam assisted gravity drainage and the oil price increases of 2004-2006, there are now several dozen companies planning nearly 100 oil sands mines and in-situ projects in Canada, totaling nearly $100 billion in capital investment.
Venezuela
Located in eastern Venezuela, north of the Orinoco River, the Orinoco oil belt competes with the Canadian oil sand for largest known accumulation (amount) of bitumen in the world. Venezuela prefers to call its tar sands "extra-heavy oil", and although distinction (difference) is somewhat academic, the extra-heavy crude oil deposit of the Orinoco Belt represent nearly 90% of the known global reserves of extra-heavy oil. Bitumen and extra-heavy oil are closely related types of petroleum, differing (different) from each other, only in the degree (amount) by which they have been degraded (broken down) from the original crude oil by bacteria and erosion. The Venezuelan deposits are less degraded than the Canadian deposits and are at a higher temperature (over 50 degrees Celsius versus freezing for northern Canada) which means they are easier to produce by conventional techniques (use a well to pump it from the ground). Although it is easier to produce, it is still too heavy to transport by pipeline or process in normal refineries.
In the early 1980's the state oil company, PDVSA, developed a method of using the extra-heavy oil resources by emulsifying (mixing) it with water (70% extra-heavy oil, 30% water) to allow it to flow in pipelines. The resulting product, called Orimulsion, can be burned in boilers as a replacement for coal and heavy fuel oil with only minor modifications (changes to the machines). Unfortunately, the fuel's high sulphur content and emission (out flow) of particulates (small particles) make it difficult to meet increasingly (more and more) strict international environmental regulations.
Continue to: Extraction Process
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Cities and Population Movement
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Possible Alternatives to Replace Crude Oil
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Extraction Process
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Environmental Impacts
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