Hysteria rather than science is driving the misconception that Bakken crude is more volatile than other types of crude oil routinely shipped across the United States, said Chauncey Naylor, director of training and fire and emergency response for Tyco Williams Fire & Hazard Control.
“We’ve got people running around saying that it’s like a bomb on wheels,” Naylor said. “It got us thinking that we ought to check into this stuff because we might be called in to deal with it.”
A review of existing data together with live-fire testing conducted by Tyco Williams F&HC shows that Bakken crude is no more flammable than other North American light, sweet crudes, he said.
“We had to throw the BS flag and say, ‘That’s not true,’” Naylor said.
Naylor presented the Tyco Williams F&HC findings at the Xtreme Industrial Fire & Hazard Training school during May in Beaumont, TX.
Bakken crude originates in the Bakken oil shale reserves of western North Dakota. Shipped by rail to refineries across the U.S., Bakken crude attracted special attention after being associated with a series of fiery derailments that have grabbed headlines in the last two years.
Worst of these was the July 2013 derailment and fire in LacMégantic, Quebec, that killed 47 people. (See IFW, Winter 2014) Alabama, Illinois, North Dakota, Virginia, West Virginia and, in Canada, Ontario have also seen fiery rail disasters involving crude oil during this period.
The first step in Tyco Williams F&HC’s Bakken crude research project conducted in November 2014 involved reviewing the readily available information such as material safety data sheets, Naylor said. The known properties include:
● Bakken crude is a light sweet crude oil with an API gravity generally between 40 degrees and 43 degrees and a sulfur content of <0.2 wt. percent.
● Bakken crude has an average vapor pressure of between 11.5 and 11.8 psi, which is more than 60 percent below the vapor pressure threshold limit for liquids under the Hazardous Materials Regulations (43.5 psi).
● Bakken crude has a flashpoint of less than 73 degrees Fahrenheit, which is within normal range.
● The Initial Boiling Point (IBP) generally averaged between 95 degrees and 100 degrees Fahrenheit, within normal range for a light crude oil (ASTM D86).
● The light ends concentration of Bakken crude was between three and nine percent, with five percent being the typical concentration.
“Everything we looked at, such as the flammable range, fell right in the range of being typical crude oil,” Naylor said. “But because of about five events in a short amount of time, it has gone from Bakken crude to voodoo crude.”
Next, Tyco Williams F&HC obtained 3,000 gallons of Bakken crude for live-burn tests conducted using a 42-foot diameter, shoulder high storage tank prop at the Beaumont Emergency Services Training complex in Beaumont.
“We got invited to North Dakota to get it pumped right out of the ground,” Naylor said. “We asked ‘Can we find some a little closer?’ We learned that it is being pumped by pipeline to a pipeline terminal in Cushing, OK. We had our truck meet it in Cushing.
” From the tank truck, the Bakken crude went straight into BEST’s petroleum storage tank fire project. About 50 people, including representatives of the U.S. Department of Transportation, were on hand to witness the test.
The crude ignited without the use of additional accelerants but was hardly an explosion, Naylor said. Flames slowly crept across the surface of the crude as would be expected.
Tactics to extinguish the flames hardly qualified as cutting edge technology. Rather than bring big monitors to bear immediately, firefighters first approached the burning tank armed with two hand lines using 95 gpm nozzles, making a “pretty sloppy application,” Naylor said. Deliberate rookie mistakes included breaking up the foam blanket and plunging the foam beneath the surface of the crude.
“The idea was to act like people who had never approached this voodoo crude before and are a little nervous,” he said. “We’re all over the place. We’re just chasing fire. But the fact is we are getting flame collapse.”
Still, the C6 foam successfully formed a quarter-inch thick film across the crude oil surface. The fire was extinguished in 3 minutes, 16 seconds.
After repeating the test using hand lines, the firefighters next used a small monitor placed 75 feet from the tank. Again, the firefighters used an application rate below what was recommended. The crude was allowed to burn uninterrupted for at least a minute.
“We allowed the steel to heat up and maintain that heat source for a re-flash or in the event that the foam doesn’t cover,” Naylor said. “But, again, the crude is slow to ignite. It’s not like gasoline or diesel flashing across the surface.”
Another deliberate error was in the application rate. A .16 application rate at 222 gpm is recommended. Instead, firefighters limited themselves to 190 gpm and a half precent concentrate.
Within four minutes, extinguishment took place.
“So that’s Bakken crude,” Naylor said. “It can be handled with conventional means using products that are available today. All you need is high performance foam, proper delivery devices and the people trained to use them.”
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