Railway Age, 2/23:
Why bitumen isn’t necessarily safer than Bakken
The chain reaction fireballs that attended the Feb. 16, 2015 derailment of a CSX unit oil train in populated West Virginia probably blinded observers to the significance of the concurrent derailment and explosions of a CN oil train in a remote and uninhabited area of northern Ontario. Most reports treated the two events as equals, given that both trains consisted of recently manufactured CPC-1232 tank cars loaded with crude oil.
CN’s Ontario conflagration is the more disturbing of the two mishaps: The railroad reported that its train was not carrying the extra-light Bakken crude that, in a series of high-energy derailments since 2013, has proved to be explosive. To the contrary, the CN train was laden with bitumen, the extra-heavy tarry substance extracted from Alberta’s oil sands. Bitumen, in its natural highly viscous form, is considered to be essentially inflammable by petrochemical experts and is rarely considered in safety evaluations of crude by rail.
So why did the bitumen ignite and explode in Ontario’s -40ºC (-40ºF) weather? The reason, based on research consulted by Railway Age, is that the diluent added to make bitumen flow into and out of tank cars makes the blended lading quite volatile.
Continue here.