PHOTO: Rita Leistner/Redux
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At the last minute, a line was inserted in the 2006
U.S. energy bill instructing the secretary of the
Department of Energy to spend US $250 000 to study an
experimental technology called cold cracking. Don’t know
what that is? Neither did the Texas congressman who
inserted the line. But that’s politics.
“We’ve got a great system,” says Bud Brainerd, whose
Alabama congressman had convinced the Texan to insert
the line. Brainerd’s the president of PetroBeam, in
Opelika, Ala., the only U.S. company conducting research
into the technology.
Cold cracking uses beams of high-energy electrons to
transform the thick parts of crude oil into oils,
gasoline, and other petroleum products thin enough to
pump through a pipeline. The question is whether a
conservative, capital-intensive oil industry will buy
the idea. To hear Brainerd tell it, refining could
certainly use something like it. A lot of new oil fields
have oil that’s too thick to pump, and that’s a shame,
because there’s so much of the stuff. There are an
estimated 2.5 trillion barrels of ultrathick oil locked
up in the sands of Alberta, Canada, alone.
Oil producers now must thin these deposits in one of
two ways. They can mix in an already refined product
containing kerosene, or they can subject the thick oil
to intense heat and pressure, which breaks some chemical
bonds, making it less viscous. Neither option comes
cheap. Brainerd believes his company’s approach could do
the job for less by cracking the heavy oil with standard
industrial irradiation equipment at room temperature and
atmospheric pressure.
The trouble is that radiation usually makes things
worse. Most of the molecules in oil are long chains of
hydrocarbons. Generally, the longer the chain, the
higher the viscosity and the less valuable the oil.
Hitting such a chain with a high-speed electron
sometimes breaks it in two, but much more often bonds it
to its neighbor in a process called cross-linking. When
that happens, an already slow-flowing soup of noodlelike
molecules is transformed into a stagnant mesh of
interconnected chains.
“That’s just the opposite way you’re trying to go in
cracking technologies,” says Walter Chappas, a nuclear
engineer and cofounder of PetroBeam. In fact,
electron-beam cross-linking is deliberately done to
manufacture plastic shrink-wrapping for packaged meats
and to toughen tires. Both applications employ
irradiation machines that resemble gargantuan,
200-kilowatt television tubes.
Researchers, particularly in countries of the former
Soviet Union, have been trying to get radiation to break
more molecules than it binds, but for a long time they
succeeded only by using an uneconomical amount of heat
and pressure. Then, in the spring of 2005, Chappas’s
co-workers from Kazakhstan finally got electrons to
crack oil under normal conditions. “What we now have is
a process that is quick, reliable, robust—in that it
processes a wide variety of feedstocks—and we can do it
very economically,” says Brainerd. He won’t reveal the
secret, except to say that it requires no adjustments to
the irradiation equipment.
Besides thinning Canada’s tar sands for transport,
the process could be used at oil refineries to turn
heavy fuel oils, used by railroads and ships, into much
more valuable gasoline and diesel. That’s currently done
in high-pressure reactors called catalytic crackers,
which operate at more than 650 °C. There are more than
300 of these reactors currently operating at refineries
around the world. Brainerd says a full-scale
cold-cracking unit could crack 10 thousand barrels of
oil a day—typical of what’s wanted in oil fields.
Right now, however, Chappas and Brainerd are limited
to testing small amounts of oil using electron guns
borrowed from plastics manufacturers. They are in talks
with refiners on partnerships to demonstrate the
technology and have raised enough money to build a
1000-barrel-per-day pilot plant. The plant will help
work out any bugs found in scaling up the technology and
will help PetroBeam prove to risk-averse refiners that
the process is in fact inexpensive.
According to Calvin Cobb, a refining industry
consultant in Houston, PetroBeam will succeed only if it
can cut the cracking cost by about two-thirds. “Nobody’s
going to tear down a catalytic cracking unit and replace
it with something that’s just a little bit better,” he says.
As for PetroBeam’s $250 000, the energy program under
which it fell was axed, and the money was never
appropriated. That, too, is politics.