Thursday, February 13, 2014

Oil sands - lookout polar vortex








Canadian oil sands development reinforcing polar vortex drift

The polar vortex is a mass of cold air which in winter rotates counter clockwise over the polar region in a cyclone fashion. An influx of warm air in the upper atmosphere (stratosphere) can cause this cyclone to weaken and even reverse at which time parts of the cold air mass can break off and be pulled southward by the jet stream.

In a usual northern-hemisphere winter, several minor warming events occur, with a major event occurring roughly every two years. One reason for major stratospheric warmings to occur in the Northern hemisphere is because orography and land-sea temperature contrasts are responsible for the generation of long Rossby waves in the troposphere (lower atmosphere). These waves travel upward to the stratosphere and are dissipated there, decelerating the winds and warming the Arctic.

Bunkum News, after obtaining an email through the freedom of information act, has learned that the Canadian government and the corporate oil industry have a two fold purpose in developing the oil sands. The first is obviously to produce and sell crude, but the second is rather devious. The heat from this massive development generates Rossby waves which because of their location in northern Alberta greatly augment any natural warming trends heading north in the stratosphere. This causes more major warmings to occur in the polar vortex and thus America has more cold spells and more oil and gas will be sold often at a premium rate.

 Since most of the oil sands bitumen is buried under about 200 feet of sediment, Steam Assisted Gravity Drainage (SAGD) is used to extract it. This involves the drilling of two horizontal wells, one at the bottom of the formation and another about 15 feet above it. The upper well injects steam into the reservoir. The resulting heat melts the bitumen which allows gravity to assist it to flow to the lower well, and the bitumen is pumped to the surface.

SAGD is still largely a brute-force method of sucking up deeply buried bitumen. At Christina Lake for example, pairs of perforated wells sink 375 meters deep, reaching a layer of bitumen 25 to 30 meters thick. There, the wells flatten out to run 800 meters horizontally through the lower third of the deposit, one well five meters above the other. Steam is forced through the top wells at 250 °C to heat and eventually melt the bitumen, which drains away from the sand, clay, and other minerals. The bottom “production” wells then suck a mix of water and melted bitumen to the surface, where the water is separated from the bitumen and recycled. Finally, the bitumen is blended with a hydrocarbon diluent to make it thin enough for pipelines before being handed off to an adjacent oil terminal and beginning its journey to refineries in the United States.

The site itself is more like a medium-sized chemical plant than a mining facility. Towering over it are five 32-meter-tall steam generators; four more are under construction. These mammoth furnaces burn natural gas and blast out 250 million BTUs of steam per hour. In all they put out the heat equivalent of 50,000 backyard grills. (With every hour of combustion and heat from Christina Lake’s steam generators comes 75 metric tons of carbon dioxide emissions—roughly 45 kilograms of carbon dioxide for every barrel of bitumen.)
The bad news for Alberta’s oil-sands industry is that Christina Lake is a best-case scenario for SAGD today. They need to steam just two barrels of water to produce a barrel of bitumen, making it Alberta’s most efficient in situ (non surface disturbing) operation. Competitors (and most future SAGD operations) must target thinner bitumen deposits, some streaked with rock and water that divert injected heat. As a result, the average barrel of bitumen produced via SAGD last year required just under three barrels of steam, according to Alberta’s Energy Resource Conservation Board. That’s why, once shipping and refining are taken into account, Alberta’s in situ production process creates far more greenhouse-gas emissions than making fuel from conventional crude.
According to the National Energy Board, it requires about 1,200 cubic feet (34m3) of natural gas to produce one barrel of bitumen from in situ projects. Since a barrel of oil equivalent is about 6,000 cubic feet (170m3) of gas, this represents a large gain in energy. That being the case, it is likely that Alberta regulators will reduce exports of natural gas to the United States in order to provide fuel to the oil sands plants. As gas reserves are exhausted, however, oil upgraders will probably turn to bitumen gasification to generate their own fuel. In much the same way as bitumen can be converted into synthetic crude oil, it can also be converted into synthetic natural gas.

Okay, back to the effect on the polar vortex. The oil sands are producing 1.5 million barrels of oil per day today. This requires 180 million cubic feet of gas to extract it (per day). For a rough idea on how much this is, it takes about 94,800 cubic feet of gas to heat a newer Canadian home for a year. This works out to heating 693,025 homes. All this heat is forced into relatively small areas and the ground heating is immense, up to 250 degrees C. Heat rises and disperses into the atmosphere but in summer when the temperature in the air is higher than in the ground little dispersion takes place, so most of the heat is radiated in winter when the temperature differential is the greatest. The email which Bunkum News obtained explains that the heated area of one half to one mile square expanses are the perfect size to generate extremely powerful Rossby waves which head straight up into the stratosphere and combine with incoming heat waves from the Pacific. This heat is all slowing down the polar vortex allowing it to intrude the southern realms.

So for our friends to the south if you don't believe this story at least you learned about our polar vortex and how the oil sands work. And don't let the cold get to you, it's a balmy plus 5 degrees Fahrenheit in Winnipeg today and we're all out in our short pants enjoying the sunshine.
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