How does a liquids pipeline work?

Crude oil, diluted bitumen (dilbit) and natural gas liquids (NGLs), such as ethane, butane and propane, are in liquid states, so the most effective way to transport them is using a series of pumping stations along a pipeline.

Entering at the source

In a typical oil field, a number of small gathering lines lead from each well to central gathering facilities – either oil batteries or natural gas processing facilities. For crude oil and diluted bitumen, feeder pipelines are used to transport the product from the oil batteries to nearby refineries or transmission pipelines.

NGLs – like ethane, propane and butane – are separated from natural gas at gas processing facilities and then transported through liquid feeder pipelines to oil refineries for processing.

Feeder lines, which are operated by oil producers, connect to large transmission pipelines to transport crude oil and other liquids long distances across the country. These transmission pipelines are operated by CEPA members.

Pumping through the transmission lines

Liquids products are moved along by pumping stations placed at regular intervals. The pumping station and pipeline form a fully enclosed system so the liquids and vapours don’t escape. Most pumping stations will have multiple pumps, each one run by an electric motor (they are quiet and have no emissions) producing around 6,500 horsepower – approximately the power of a typical locomotive.

A worker analyzes liquids product. Photo courtesy of Enbridge Pipelines.

A worker analyzes liquids product. Photo courtesy of Enbridge Pipelines.

The liquids move through the lines at about five kilometres per hour.

Storing the liquids

When liquids products are being transported, they often need to be temporarily stored before safely reaching their destination. That’s w­here above ground storage tanks come in. These cylindrical structures pop up along the route of an underground pipeline and are designed to safely hold liquid petroleum products.

Delivering dilbit

Dilbit stands for diluted bitumen, and is a semi-solid form of oil from the oil sands that is mixed with a thinner liquid (natural gas condensate, naphtha or other light hydrocarbons) to dilute it for easier transport. It’s no different than ordinary crude oil – in fact, dilbit has been shipped to refineries by transmission pipelines for over 30 years.

As dilbit is a liquid, the best way to move it is to use a series of pumping stations along a pipeline. Once at the refinery, dilbit is processed to remove the diluent so it can be reused. Bitumen is refined into the various products we rely on every day, like gasoline, diesel, asphalt, motor oil, ship fuel, home heating fuel and aviation fuel, along with hundreds of other products.

Refining crude oil

Crude oil – oil directly from the well – is shipped to refineries by transmission pipelines operated by CEPA members. It’s then refined into the various products we rely on every day, like gasoline, diesel, asphalt, motor oil, ship fuel, home heating fuel and aviation fuel, along with hundreds of other products. Refined products, like gasoline and diesel, are shipped through transmission lines to storage facilities near consumers.

Smaller distribution lines, or tankers, transport product directly to users.

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“We must build anew and replace all of the aging infrastructure so it does not leak.” – Bruce F. (London, Ont.)
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