The National Academy of Sciences released a new report today, Special Report 311: Effects of Diluted Bitumen on Crude Oil Transmission Pipelines, refuting many claims that Diluted Bitumen or Dilbit from Canadian oil sands will corrode pipelines.
As discussed in Chapter 3, the bitumen imported into the United States is derived from Canadian oil sands. Canadian bitumen is both mined and recovered in situ using thermally assisted techniques. A large share of the bitumen deposits is too deep for mining, so in situ recovery accounts for an increasing percentage of bitumen production. Because mined bitumen does not generally have qualities suitable for pipeline transportation and refinery feed, it is processed into synthetic crude oil in Canada. Bitumen recovered in situ with thermally assisted methods has lower water and sediment content and is thus better suited to long-distance transportation by pipeline than is mined bitumen. Bitumen imported into the United States is produced in situ through thermally assisted methods rather than by mining. (Page 71)
Some critics claim that Canadian oil sands is different from conventional crude oil. The National Academy report disputes this claim as well:
The dilution process yields a stable and fully mixed product for shipment by pipeline with density and viscosity levels in the range of other crude oils transported by pipeline in the United States. (Page 72.)
The good news for people who are concerned about the safety of the Keystone XL pipeline is the National Academy study has similar findings to earlier studies.
Studies by petroleum chemical experts have also concluded that diluted bitumen behaves the same as other forms of crude oil and does not lead to more corrosion in pipelines. A study released earlier this year by the U.S.-based Batelle Memorial Institute concluded that “diluted bitumen poses no more of a corrosion risk to pipelines than conventional crudes.” Similarly, a study by Alberta Innovates found that diluted bitumen may actually be less corrosive to steel pipelines than conventional crudes. And an international standards organization has also concluded the same based on new research involving scientists from Natural Resources Canada.