Bitumen floats longer than expected, Natural Resources Canada research shows

As reported in the Vancouver Sun, researchers at Natural Resources Canada are discovering important characteristics of bitumen (the un-processed form of crude oil from the Alberta oil sands) and its interactions with the environment.  Information from the research will be useful in the development of strategies and technologies to clean-up bitumen in the event that is leaks into the environment as a result of a pipeline leak or tanker spill.

One important question with respect to bitumen is whether it sinks or floats when it hits the water. The short answer is it floats, most of the time, according to a growing body of research being compiled by Natural Resources Canada scientists.

Researcher Heather Dettman, a senior scientist with Natural Resources Canada in Devon, Alta., is leading a team looking into some of those questions in research under the federal government’s world-class tanker safety program and ocean protection program.

Postmedia caught up with her and a spokesman from Western Canada Marine Response Corp. to talk about answers.


Q: What is diluted bitumen?

A: Bitumen is the basic, tar-like petroleum product extracted from the Athabasca oilsands, which are oil deposits that were first formed deep underground, but were moved closer to the surface by geological movements of the earth. That allowed microbes to degrade the components that make up gasoline and diesel leaving only its asphalt components. Producers inject those lighter components back into bitumen to make it thin enough to flow through pipelines.

Q: How would rough seas change the behaviour of diluted bitumen?

A: “From a density perspective, it will be floating unless it’s really stormy, then it can go anywhere, the same as any other petroleum product,” Dettman said.  If a storm pushed bitumen ashore, it would pose the problem of having to clean it up on land.

Q: Has there ever been a spill of diluted bitumen on the coast?

A: The biggest spill that the Western Canada Marine Response Corp. has dealt with involved a mix of bitumen and synthetic oil, said spokesman Michael Lowry.  That was the 2007 puncture of Kinder Morgan’s Trans Mountain pipeline in Burnaby that led to about 100 tonnes of oil flowing down storm drains into Burrard Inlet.  In nice weather and close to the industry-funded spill responders’ facilities, Lowry said they were able to recover 90 per cent of the oil.

“Those are ideal conditions; I can’t extrapolate those to other spills for sure,” Lowry said.

Kalamazoo River diluted bitumen spill clean-up

Q: How do you clean up a bitumen spill?

A: Lowry said methods haven’t changed much over the years. Chemical dispersants, in situ burning and mechanical recovery are the techniques that responders use, but since the first two require government permission, the corporation focuses on mechanical recovery — booming and skimming. From its 2007 experience, Lowry said responders learned that its brush skimmers — conveyors that rotate heavy plastic brushes over the surface to collect oil — were particularly effective.

“Conditions play a huge role in recovery,” Lowry said. “High winds are going to impact your ability to respond and rough seas definitely impede your ability to respond.”

Q: What research is being done to improve spill response?

A: Lowry said new tools are being developed, such as advanced booming systems that perform better under tougher conditions, which the corporation deploys.  In the meantime, Lowry said Environment Canada and Natural Resources Canada are putting resources into studying the topic.