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Tar Sands No Worse Than Other Oils for Pipeline Spills

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Feeder pipelines, like the one in the foreground here, must be rotated to prevent wear. Image © David Biello

The oil derived from Canada’s tar sands is more acidic than other forms of petroleum. So does this mean that diluted bitumen (or “dilbit”) is more corrosive when flowing through a pipeline? The answer is no, according to the U.S. National Academy of Sciences’ National Research Council.

A review of U.S. pipeline ruptures over the last 30 years, along with chemical analyses of the dilbit itself and other factors, show that the tarry stuff is no worse for pipelines than other forms of oil. Or, as chemical engineer Mark Barteau of the University of Michigan put it in the press release announcing the finding: “There’s nothing extraordinary about pipeline shipments of diluted bitumen to make them more likely than other crude oils to cause releases.”

The key appears to be the fact that the higher total acids in dilbit are not any more corrosive at pipeline operating temperatures of around 65 degrees Celsius, which was also the conclusion of studies by the Albertan government. Dilbit is more corrosive, however, at temperatures above 100 degrees C, the kinds of temperatures found in the refinery where the dilbit presumably ends up.

The finding also only applies to long-distance transportation pipelines, not the kinds of pipelines that carry tar sands oil around the mine or underground melting facilities in Alberta itself. Those pipelines are more susceptible to corrosion and other causes of ruptures thanks, in large part, to the sharp grit still in the tar sands oil at that point. The sand in tar sands wears away wears away the interior walls of these pipelines on a regular basis, so much so that oil sands producers turn the pipelines in place on a regular basis like rotating the tires on a car.

And the finding does not address the question of whether dilbit spills might be worse for the environment than leaks of more conventional crudes. Dilbit has some unique properties that make it more likely to sink in water, among other potential challenges. The residents of Mayflower, Ark. and Kalamazoo, Mich., the locations of major dilbit spills from pipelines, found this out the hard way.

Regardless, the largest environmental problem with tar sands oil isn’t ruptures or spills, it’s the invisibly accumulating greenhouse gases released during production and when the resulting fuels are burned to move our cars, trucks and airplanes around the world. You can learn more about the problem of this “greenhouse goo” in the July issue of Scientific American. So we can safely move dilbit through pipelines most likely, but to what end?

About the Author: David Biello is the associate editor for environment and energy at Scientific American. Follow on Twitter @dbiello.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. Unksoldr 12:51 pm 06/27/2013

    You should actually say the Oil Companies say it’s just as safe as crude oil.

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  2. 2. geekwithsoul 12:56 pm 06/27/2013

    That has to be one of the most inaccurate headlines I’ve ever read from Scientific American. The entire piece is about one, single aspect of diluted bitumen transport, and and a minor one at that (unless you’re the owner of the pipeline and have to take care of the maintenance). Yet the headline makes it sound like a dilbit spill can be treated like any run-of-the-mill spill, and as evidence has shown, that’s simply not the case.

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  3. 3. M Tucker 3:10 pm 06/27/2013

    “Regardless, the largest environmental problem with tar sands oil isn’t ruptures or spills…”

    How can you say that? The study didn’t address that issue. You said as much in the paragraph directly above this quote. “…the finding does not address the question of whether dilbit spills might be worse for the environment than leaks of more conventional crudes.”

    “The residents of Mayflower, Ark. and Kalamazoo, Mich., the locations of major dilbit spills from pipelines, found this out the hard way.” Yeah, with the belief that “the largest environmental problem with tar sands oil isn’t ruptures or spills…” I guess we will all have to find this out the hard way. You ought to visit one of those places. It isn’t just that it can’t be skimmed from the surface of the water that is a problem. Please go to a spill site and report back on what you smell, how well you are able to breath, how you eyes feel.

    Tar sand oil is bad from beginning to end and everywhere in between.

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  4. 4. CharlieinNeedham 12:33 am 06/28/2013

    Tar Sands No Worse than Other Oils for Pipeline Spills

    Great news.

    Time to build that Keystone pipeline for a sure source for raw petroleum instead of depending on the turbulent Middle East.

    That pipeline is much less threatening to the environment that waiting for Canada to build one through the Rockie Mountains to dangerously load huge cargo ships like the Exxon Valdez.

    Because the sun doesn’t shine at night and the wind doesn’t always blow, it seems that petroleum still remains a “greener” energy source than coal.

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  5. 5. singing flea 1:49 am 06/28/2013

    Who cares? A spill is a spill. You can’t justify environmental homicide just by comparing other methods of doing the same damage. Jeesh! Will some authors ever wake up?

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  6. 6. singing flea 1:53 am 06/28/2013

    How about we just tell it like it is?

    Tar sands just as bad as other oil pipeline spills!

    It’s all in the way you word it David B.

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  7. 7. Owl905 3:46 am 06/28/2013

    “Time to build that Keystone pipeline for a sure source for raw petroleum instead of depending on the turbulent Middle East.”
    That dog not only won’t hunt, it’s been neutered in Congressional Hearings. The tar sands plan is to ship to Texas for refining of diesel for the global market-five of the six buyers are foreign, and the sixth has an export focus. They do jack squat for the declining dependence of the USA on foreign oil. Nor does it shield America from price-shocks – since the global price is set by global conditions.
    America is now a net exporter, so that ‘vulnerable’ angle is DOA as well.
    The pipeline is risking American land to help multinationals find an existing refinery to exploit. That’s all it is. And it ain’t no more.
    Note: if this stuff is so ‘precious’ why doesn’t the Canadian Government build local refineries and ship the diesel? Ans: because it’s just plain P&L sense to use the Texas refineries.
    And the back door about GHG pollution is tongue-in-cheek pablum because the State Department has already issued a get-out-of-jail free card by stating if it isn’t Texas it’s someplace else … so the ‘significant pollution’ protection clause is gone.

    Stop playing in the street when the street has access to the info.

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  8. 8. kienhua68 8:51 am 06/28/2013

    I don’t think pipeline failure is the real threat. Rather cleaning up dilbit spills which is from all reports is much more difficult.
    I think we know that if a pipeline exists, it will leak at some point. This seems the case everywhere that oil is piped. Some leaks are the result of external corrosion. So talking about whether or not its more corrosive to the pipe misses the point.

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  9. 9. Wayne Williamson 1:49 pm 07/4/2013

    I still don’t see why the don’t build a refinery by the source. Why spend the billions to send it thousands of miles away to be refined.

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  10. 10. 5:53 pm 07/4/2013

    @ Wayne Williamson. Why isn’t bitumen refined on site? Now there’s the dirty little secret.

    The bitumen exported through those pipelines contains a really vile form of coal called petroleum coke or petcoke that can run 15 to 30% by volume. Petcoke is far higher in carbon than conventional coal and, worse, really high in sulfur. It’s nasty stuff that most decent countries won’t allow to be burned because of its emissions. So it’s exported, out of sight/out of mind, to be burned in China and elsewhere they can find a market for this really cheap fuel.

    The bitumen producers mislead the public by claiming their product is not greatly higher in CO2 emissions than conventional oil. They would just rather not have any mention of their secondary export, petcoke.

    As for the pipeline risks, have a look at the track record of the biggest company, Enbridge. It’s an eye-opener.

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  11. 11. Plain-2009 1:46 am 07/5/2013

    I am sorry.
    It is a horrible idea to transport this substance long distances.
    Without entering into a detail study of the subject matter, at first sight it seems a very bad thing to build such a pipe line.
    Obviously our dream is not to use fossil fuels any more and clean the atmosphere once and for all.
    That petroleum sand is a valuable asset, no doubt about it. Hopefully it will not be used to produce fuel. Many other things can be produced.
    On the other hand it is difficult to image that we can stop using fossil fuels overnight.
    It is extremely important to have something to substitute fossil fuels.
    If government regulations make imperative not to use fossil fuels in North America, what about the rest of the world?
    Just to mention one single example, China (it seems) is getting richer. China wants to use cars, and it seems it is heavily populated.
    How difficult would it be to reach an International Agreement not to use fossil fuels any more or to go gradually diminishing the use of fossil fuels until those poisonous substances are phase out at all?
    Are we really damaging the atmosphere? To what extent? How dangerous is the situation?
    Here where I live the birds sing and fly all day long and seem to have no concerns at all about how clean the atmosphere is.
    My personal view is that the atmosphere is not clean and it is about time to do something about it.
    This a very serious matter.

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  12. 12. khargett_dk 4:14 am 07/6/2013

    In the summary of Chapter 4 – Review of Pipeline Incident Data it says:
    “The incident statistics can be used to identify the general sources of pipeline failure. However, the information contained in the U.S. and Canadian incident records is insufficient to draw definitive conclusions. One reason is that the causal categories in the databases lack the specificity needed to assess the particular ways in which transporting diluted bitumen can affect the susceptibility of pipelines to failure. Another reason is that incident records do not contain information on the types of crude oil transported and the properties of past shipments in the affected pipeline.”

    In other words, The report is totally useless in answering to the statistics of oil sands pipeline failures!!!

    Link to this

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