BISMARCK,
N.D. (AP) — State geologists are hopeful North Dakota’s sands and clays
will work as a substitute for increasingly sparse imported materials
used to boost the recovery of crude.
A
worldwide supply crunch of so-called proppants — ultra-hard sand grains
and tiny manmade ceramic balls — has some drillers using lesser-grade
particles that have cut the yield of oil wells in the Bakken and Three
Forks formations in western North Dakota.
“The
reality is people are sold out of everything,” said Mike Vincent, a
Golden, Colo.-based engineer. “People are taking whatever they can — an
extremely low quality material is being pumped into the Bakken.”
Proppants,
some the size of a grain of sugar, are used in hydraulic fracturing, a
process that uses pressurized fluid and chemicals to break open
oil-bearing rock some two miles underground. Cracks, propped open by
injected sand or ceramic materials, provide a pathway for oil to flow to
the well.
Demand
for proppants — pushed by high crude prices — has jumped 400 percent in
the past decade, said Vincent, president of Insight Petroleum
Consulting LLC, a company that specializes in improving the efficiency
of hydraulic fractures.
There
are only a handful of proppant manufacturers in the North America; much
of what is used in the U.S. is being imported from factories in Russia,
China and Brazil, industry officials say.
There
are about 20 sand suppliers and 20 ceramic proppant suppliers
worldwide, said Earl Freeman, a vice president of PropTesters Inc., a
Houston-based proppant testing company.
Crushed
walnut hulls were first used as a proppant in the 1940s, followed by
hardened glass beads and sand, he said. Resin-coated sands and ceramic
proppant has been used since the 1970s.
Geologists
have been analyzing North Dakota’s clay and sand deposits for about two
years hoping to find potential proppant material, said Fred Anderson, a
geologist with the state Geological Survey in Bismarck.
“We are starting to feel a pinch based on global demand so now we have to look at other options,” Anderson said.
A
Bakken well can cost about $6 million to drill, and proppant costs
average about 5 percent of the well cost and are increasing, Anderson
said. Ceramic proppants, which typically allow more oil to be recovered
from a well because of their hardness, can cost 10 times as much as
sand, he said.
Sand
proppants must be uniform in grain size, extremely hard and near
perfectly round, said Ed Murphy, the state geologist and director of the
Geological Survey.
“We’ve
certainly looked at a lot of sands that won’t work and about a dozen or
so that may meet some of the criteria,” Murphy said.
Even
the North Dakota’s best sand candidates likely would not be ideal for
proppants in 2-mile deep formations like the Bakken and Three Forks,
geologists say. Deeper formations create more pressure and can crush
natural sand.
But
geologists also have identified deposits of koalinitic clays that could
be used as an ingredient for ceramic proppants, Murphy said. Kaolinite
is used as raw material for the more than century old the Hebron Brick
Co. plant in western North Dakota, he said.
A
Bakken well can require more than 3 million pounds of proppant, and
high-grade ceramic proppants can increase the recovery of a Bakken well
by 20 to 150 percent over the natural particles, said Vincent, of
Insight Petroleum Consulting.
Murphy
said his agency will ask lawmakers for $50,000 to have sands and other
raw materials tested for proppant applications. Results of the testing
could be completed this summer, he said.
The agency would make available the results to industry, Anderson said.
“It will be up to the entrepreneurial spirit to put the puzzle pieces together,” Anderson said.
SOURCE: The Associated Press
