The Great Oil Sands Journey Part 3

Bitumen finally grows up

Once you manage to get the bitumen separated from the sand, the next step is to get it upgraded, a process needed to convert bitumen into a product with a density and viscosity similar to conventional light crude oil. Upgrading, like life, comes in a series of stages.

Wells to Wheels
Part three of a five-part series

The first stage deals with breaking up the enormous carbon molecules. We’ll look at this as similar to being a child because they still have many school years to complete before they are ready for a career, though, to be fair, they have already come quite a long way. For bitumen, the ultimate goal is to get a career in fueling cars, jets or furnaces, or becoming a plastic or asphalt. Just as there are many jobs in the world, so too are there many petroleum products.

Bitumen contains more carbon-rich hydrocarbon molecules than conventional oil, so it’s important to upgrade the bitumen into a product that refiners can work with. This is usually done through a process called “coking” which breaks down heavy oil molecules into lighter ones by removing the carbon. Another approach is hydro-processing, which adds hydrogen under high-pressure to help balance out the carbon to hydrogen ratio. If you’re torn between which of the processes to use next time you want to break down some carbon-heavy molecules, a common approach is to do both.

The second stage is a process called hydrotreating. We’ll look at this stage as similar to being a highschool student. These students have accomplished many years of school and soon they will be graduating. If there is anything still childish in them, they are encouraged to get it out of their systems now. The same is so with bitumen. Hydrotreating, for example, removes childish things like sulphur and nitrogen.

Once upgrading has happened, the oil must be refined. This is the process of transforming the crude oil into a classy, well-dressed product. Well, actually, we’re going to look at this phase as the college student phase. First, what refining does is distill the oil at various temperatures to make various products. Of course, all refineries are different, but ultimately they separate and process the mix of hydrocarbons in the oil, transforming it into a whole array of different products like gasoline, lubricants, diesel or jet fuel, depending on which tray it evaporates up to and settles on after it has been heated. Think of this as like specialization. Before people can enter the work world, they should specialize their learning in certain subjects that match their interests and aspirations. The crude oil’s final product – its destiny – is determined by its makeup, its boiling point and the tray upon which it settles.

Here’s refining in a nutshell

This separation is done through an atmospheric distillation tower which is a tall steel tower layered with perforated trays at different levels. Each petroleum product has a different boiling point so the distillation tower is able to separate the different products through heating and cooling. The distillation process is continuous and begins by heating crude oil in a furnace until it turns into a vapour which rises through perforations in the trays. As the vapours rise, they shed their heaviest components, which condense onto the tray, liquefy and are then drawn off the tray by pipes. Heavier hydrocarbons boil at a much higher temperature than lighter ones, so they settle in trays near the bottom or middle-bottom, resulting in products like jet, diesel and furnace fuels. Lighter oils collect at the top, resulting in products like light gasoline and petrochemicals.

Interestingly, despite the fact that much of Canada’s fuel demand is met through oil sands, much of the bitumen is sold to U.S. refiners rather than being refined here in Canada. This is mainly because Canada’s older refineries are designed to process predominately low-sulphur light crude oil. However, some Canadian refineries are being retrofitted to handle synthetic crude.

The fact that oil sands refining jobs and opportunities go south has caused quite a stir in recent times. With the struggling economy, many organizations, such as the Alberta Federation of Labour, are speaking out and urging the Alberta Government to intervene and stimulate the creation of refineries, and jobs, in Alberta.

So there you have it… the full process of oil’s journey from the oil sands mine or in-situ well, right up to the point where it becomes a refined product that is ready and willing to do its job. And just as it is so in life, entering into the work world is just another beginning.

Next week:  Wheels to Winds – Everyone wants a piece of the plump pump pie