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Larger lines (up to 20 centimetres (eight inches) in diameter) connect groups of batteries with local refineries or with still larger trunk lines (up to 120 centimetres (47 inches) in diameter) which feed refineries across the country.
Where gathering systems are not available, oil is transported by truck to trunk lines. Crude oil and refined products are also transported by ship and by railway.
The oil is moved along the pipelines by powerful centrifugal pumps spaced along the line at intervals depending upon pipeline size, capacity and topography.
Different types of oil, heavy oil, bitumen and natural gas liquids travel in batches at between four and eight kilometres per hour. Because the different batches in a pipeline move as a continuum at the same speed, there is no need to separate them. Mixing only occurs where two batches come in contact with each other and these small volumes, known as transmix, are reprocessed.
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Major Crude Oil Pipelines
Enbridge Pipelines’ crude oil pipeline system stretches from Norman Wells in the Northwest Territories to northern Alberta and from Edmonton eastward to Sarnia, Toronto, Montreal and the central United States. The leg between Sarnia and Montreal, originally built to carry Western Canadian crude oil eastward, was reversed in 1999 so that it now brings imported and offshore Canadian oil production westward to Ontario refineries.
The Trans Mountain system, owned by Kinder Morgan, carries crude oil and refined products westward from Edmonton to Vancouver and into Washington State. Kinder Morgan also operates the Express Pipeline, which carries crude oil from Hardisty, Alberta, to Wyoming where it joins another Kinder Morgan pipeline, the Platte, to supply markets in the Midwestern United States.
Other pipelines that transport crude oil south from Alberta to Montana include the Rangeland, Milk River and Bow River systems. The Wascana pipeline carries crude oil from Saskatchewan into Montana.
Pipeline systems operated by Enbridge, Kinder Morgan and other companies also transport synthetic crude oil, heavy oil and bitumen to refineries and marketing terminals in Alberta. The Cochin Pipeline carries natural gas liquids, such as propane and petrochemicals, such as ethylene from Alberta to Sarnia, and the Trans-Northern Pipeline supplies refined petroleum products in southern Ontario and Quebec.
Canada’s crude oil imports arrive by tankers at East Coast ports or at Portland, Maine, for shipment by pipeline to Montreal. There has also been some tanker transport of oil products on the Great Lakes.
There are currently 16 refineries in Canada: two in British Columbia, three in Alberta, one in Saskatchewan, four in Ontario, three in Quebec and three in the Atlantic Provinces, all of which are connected to the pipelines system.
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Natural Gas Pipelines
Approximately 484 million cubic metres (17.1 billion cubic feet) of natural gas per day travel through Canada’s natural gas pipeline network which, like oil pipelines, comprises everything from small-diameter plastic gathering lines to steel conduits more than a metre in diameter.
Unlike crude oil, natural gas is generally delivered directly to the consumer by pipeline. However, it begins that journey in a manner similar to crude oil. Gas wells are connected to small-diameter (five centimetres to 15 centimetres; two inches to six inches) gathering systems that take the gas to a gas processing facility. Gas processing facilities, usually referred to as gas plants, vary in size from small compression facilities that are mounted on moveable platforms and that remove impurities and water from the gas, to large gas plants that also remove sulphur and carbon dioxide. Some gas plants also extract ethane, propane, and butane, which are referred to as natural gas liquids or NGLs. The generally dry gas may then be compressed prior to moving into the transmission system which consists of steel pipe from 50 centimetres (20 inches) to more than a metre (39.4 inches) in diameter.
Gas flows through the system from areas of high pressure to areas of low pressure through the use of compressors, turbines similar to jet engines that increase the pressure of the gas up to 10,300 kilopascals (1,500 pounds per square inch). Compressor stations are placed at regular intervals along the pipeline to increase line pressure which is reduced due to friction of the gas moving through the pipe.
Transmission line compressors are most often driven by gas turbines with the necessary fuel being taken from the pipeline. Where electricity is preferable, electric motors may be used to drive compressors.
Transmission systems move the gas across great distances to local distribution companies or gas utilities, where the pressure is reduced and the gas enters a distribution main for local delivery to service lines connected to individual homes or businesses.
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Major Natural Gas Pipelines
The Alberta system of TransCanada PipeLines Limited (TransCanada) carries the greatest volume of natural gas in Canada. The Alberta system gathers gas from producing areas around the province and transports it to distribution systems, industrial customers and other transmission systems serving markets in Canada and the United States. Straddle plants, facilities which straddle the pipeline and remove natural gas liquids, are located at the Alberta borders. |
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TransCanada also owns the largest interprovincial natural gas pipeline in Canada. It is one of the world’s longest natural gas transmission lines, extending from the eastern Alberta border into Quebec with numerous connections to the United States.
In British Columbia, Spectra Energy (formerly Westcoast Energy Inc.) operates gathering lines and gas processing plants as well as the main natural gas transmission system. TransGas Limited operates the collection, transmission and distribution system in Saskatchewan.
The Maritimes & Northeast Pipeline main pipeline was built in 1999 to bring natural gas to markets in the Maritimes and Northeastern United States from six developed natural gas fields 160 kilometres (100 miles)offshore from Nova Scotia. The natural gas is delivered to shore by a pipeline laid in a trench on the sea floor. The Canadian portion of the onshore line stretches 568 kilometres (350 miles) from Goldboro, Nova Scotia to St. Stephen, New Brunswick, and connects to several smaller lines that deliver gas to consumers in Nova Scotia and New Brunswick.
The Alliance Pipeline, which began operation in late 2000, stretches from northeastern British Columbia to the Chicago area, and carries, at very high pressure, both natural gas and natural gas liquids as a single dense phase fluid. Other significant transmission systems include Trans Quebec & Maritimes Pipeline Inc. in Quebec and Terasen Gas, which operates a natural gas pipeline to Vancouver Island.
In 1912, Canadian Western Natural Gas (now part of the ATCO Group) completed a natural gas pipeline from Bow Island to Calgary. ATCO Pipelines operates more than 8,400 kilometres (5,220 miles) of natural gas pipeline. ATCO Gas owns and operates a 36,000-kilometre (22,370-mile) natural gas distribution system in Alberta.The original pipelines have been replaced and new pipelines continuously added. The ATCO system now totals 8,400 kilometres (5,220 miles), all within Alberta.
To balance supply and demand, several natural gas companies operate storage facilities in depleted oil and gas fields and underground salt caverns. The largest storage facilities are located in central and eastern Alberta and southwestern Ontario.
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Product Pipelines
Product pipelines carry refined products such as gasoline, diesel, jet fuel, heating oil and lubricants from refineries to terminals or local distribution centres. Like oil pipelines, centrifugal pumps move the products through the line. Pipe diameters range from 20 centimetres to as high as 106 centimetres (eight inches to 42 inches).
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