Nav: Home

Sawdust reinvented into super sponge for oil spills

December 12, 2016

SEQUIM, Wash. - Lowly sawdust, the sawmill waste that's sometimes tossed onto home garage floors to soak up oil spilled by amateur mechanics, could receive some new-found respect thanks to science.

Researchers at the Department of Energy's Pacific Northwest National Laboratory have chemically modified sawdust to make it exceptionally oil-attracting and buoyant, characteristics that are ideal for cleaning oil spills in the icy, turbulent waters of the Arctic. The nontoxic material absorbs up to five times its weight in oil and stays afloat for at least four months.

"Most of today's oil remediation materials are designed for warm water use," said PNNL microbiologist George Bonheyo, who leads the modified sawdust's development from PNNL's Marine Sciences Laboratory.

"But as ice retreats in the Arctic Sea, fossil fuel developers are looking north, and we need new oil spill response methods that perform well in extreme conditions," added Bonheyo, who also holds a joint appointment in bioengineering with Washington State University.

"The chance of an oil spill in the Arctic is real," said fellow PNNL microbiologist Robert Jeters, who is also part of the project. "We hope materials like our modified sawdust can help if an accident happens."

SEE THE VIDEO: https://www.youtube.com/watch?v=DWb6dz_tzfg

>Fire & ice

Containing oil spills in cold waters is especially tricky, as bobbing ice chunks push oil below the water's surface, making it difficult to collect. The same goes for rough waters, whose tall, clashing waves disperse oil.

The modified saw dust pulls double duty. Beyond absorbing oil, it also enhances another approach to combatting oil spills - controlled burns. If changing weather or tides move spilled oil toward a sensitive area fast, oil can be burned before it can cause further harm. Called in-situ burning, the practice can significantly reduce the amount of oil in water and minimize its adverse environmental effects.

Bonheyo and his team looked to develop an environmentally friendly and inexpensive material that floats despite rough or freezing waters and can support in-situ burning. Not wanting to create more pollution if emergency responders can't retrieve oil cleanup material, Bonheyo's team considered other natural ingredients like rice hulls and silica. But they ultimately found their winner in a fine dust called wood flour. A woodworking byproduct, wood flour is often used to make wood composites.

To make the dust into a thirsty oil mop, researchers chemically attach components of vegetable oil onto the material's surface. These attachments make the modified material oil-grabbing and water-shunning. The final product is a light, fluffy, bleached powder. The team is also trying out adding tiny, oil-eating microbes - fungi and bacteria - to the powder's surface so any left-behind material could naturally break down oil over time.

Just a sprinkle

Applying the modified sawdust is simple: sprinkle a thin layer over oil on the water's surface. The material immediately starts soaking up oil, creating a concentrated and solid slick that stays afloat thanks to the material's buoyant nature. The oil-soaked material can either be burned or retrieved.

The team is using PNNL's unique Arctic simulation lab in Sequim, Washington to evaluate the material in icy waters. The facility is a customized shipping container that cools down to as low as 5 degrees Fahrenheit, which prompts researchers to don snowmobile suits and ski masks while they work. Ice slush forms on the surface of water that circulates inside a 290-gallon raceway pond placed inside the bitterly cold lab space. Oil is spilled on the slushy surface, followed by a sprinkle of modified sawdust. Tests have shown the material's water-repellent nature prevents ice from forming on it, allowing it to soak up oil and remain at the surface.

Researchers are also testing how well the material performs in controlled burns. They conducted initial burns this fall at the U.S. Coast Guard and Naval Research Laboratory's Joint Maritime Test Facility near Mobile, Alabama. Burn tests continue today at PNNL's Marine Science Laboratory. Early results indicate a small amount of material enables burning of both thin and thick layers of spilled oil.

In the coming months, PNNL will further evaluate the modified sawdust. The material will need additional testing and approval by multiple agencies before it can be used at actual oil spills.

PNNL is developing the material for the Department of Interior's Bureau of Safety of Environmental Enforcement. BSEE is the lead federal agency charged with improving safety and ensuring environmental protection related to the offshore energy industry, primarily oil and natural gas on the U.S. Outer Continental Shelf.
-end-
The material's development team includes Bonheyo, Jeters, Yongsoon Shin, Jiyeon Park, Andrew Avila and Maren Symes.

Interdisciplinary teams at Pacific Northwest National Laboratory address many of America's most pressing issues in energy, the environment and national security through advances in basic and applied science. Founded in 1965, PNNL employs 4,400 staff and has an annual budget of nearly $1 billion. It is managed by Battelle for the U.S. Department of Energy's Office of Science. As the single largest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information on PNNL, visit the PNNL News Center, or follow PNNL on Facebook, Google+, LinkedIn and Twitter.

DOE/Pacific Northwest National Laboratory

Related Oil Spill Articles:

BP oil spill did $17.2 billion in damage to natural resources, scientists find
The 2010 BP Deepwater Horizon oil spill did $17.2 billion in damage to the natural resources in the Gulf of Mexico, a team of scientists recently found after a six-year study of the impact of the largest oil spill in US history.
Economists price BP oil spill damage to natural resources at $17.2 billion
The BP oil spill in the Gulf of Mexico was the largest maritime oil spill in US history.
Seven years later: BP oil spill settlement funding new way to manage fish populations
Researchers from the University of South Florida College of Marine Science played a key role in understanding the severity of the BP oil spill.
Coming soon: Oil spill-mapping swarms of flying drones
Partly inspired by the dynamics of a flock of birds, engineers devised a computational method for drones to quickly record whether they are over water, oil or the edge of the spill.
Scientists report on latest Deepwater Horizon oil spill impacts
LSU scientists will present new research at the 2017 Gulf of Mexico Oil Spill and Ecosystem Science Conference in New Orleans next week.
Researchers ask important questions on what happens to oil after a spill
Very little is known about what happens to oil in the ocean after an oil spill and what happens to it once a chemical dispersant has been applied.
Gulf oil spill research featured in special issue
The Deepwater Horizon oil spill was not only the largest ecological disaster in the US, but it has become the most scientifically researched oil spill.
Deepwater Horizon oil spill caused widespread marsh erosion
Marsh erosion caused by the 2010 Deepwater Horizon oil spill was widespread, a new study of 103 Gulf Coast sites reveals.
Nanofur for oil spill cleanup
Some water ferns can absorb large volumes of oil within a short time, because their leaves are strongly water-repellent and, at the same time, highly oil-absorbing.
'Dirty Blizzard' sent 2010 Gulf oil spill pollution to seafloor
Scientists working in the Gulf of Mexico have found that contaminants from the 2010 Deepwater Horizon oil spill lingered in the subsurface water for months after oil on the surface had been swept up or dispersed.

Related Oil Spill Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...