ShareThis Page

New weapon against oil spills

| Saturday, Dec. 17, 2016, 9:00 p.m.

ANCHORAGE, Alaska — Federal researchers looking for ways to contain petroleum spills in frigid Arctic waters are investigating whether a powder form of humble sawdust can provide a solution.

Researchers at the Department of Energy's Pacific Northwest National Laboratory are testing chemically modified wood flour to determine whether it can enhance the burning of crude oil after a spill.

Tests of small batches treated with components of vegetable oil indicate the material will grab onto crude oil and help keep it near the surface. PNNL senior research scientist George Bonheyo, who is also a research professor of bioengineering at Washington State University, calls the material “incredibly buoyant, ice-repelling and water-repelling.”

“It really, really loves oil,” Bonheyo said. “It absorbs at least five times its weight in oil.”

Environmental groups say challenges with cleaning an oil spill are amplified in the Arctic and it's one of their primary objections to drilling off Alaska's northern coast. The location is far from ports and other infrastructure taken for granted at drilling sites such as the Gulf of Mexico. Storms are fierce and Arctic waters can be open, frozen or partially covered, with ice ranging from floes to slush.

Mechanical recovery has not proven effective because ice can jam skimmers. Researchers at the PNNL lab have focused on burning and bioremediation.

“The point with doing a burn is that it allows you within a matter of minutes to remove upward of 90 percent of the oil from the water,” Bonheyo said.

To burn, he said, untreated crude oil must be fresh and at least 3mm thick, a little more than two stacked dimes. Early results from lab tests of the chemically treated sawdust indicate the material will help keep an oil slick together in the face of buffeting by wind, waves or ice, Bonheyo said, and allow it to burn in thinner amounts.

“We know we can get below 1 mm,” he said. “We don't know exactly what the minimum thickness is.”

Crude oil weathers when absorbed by the material but remains buoyant for at least four months.

“It works very well at holding a spill together. It seems to act kind of like a wick, allowing the volatile, flammable components to rise up to the surface to facilitate an efficient burn,” Bonheyo said.

Bonheyo has a background in research on ship hulls to prevent fouling by organisms. Researchers are looking into adding a bioremediation element to the chemically modified sawdust. Mixtures of organisms adapted for different hydrocarbons, and adapted for different environments, could be added to the wood-based product.

“The idea there is, if any of the oil with the sawdust escaped a burn site, the microbes would be there to consume the escaped oil,” Bonheyo said.

Researchers have conducted burn tests of Alaska North Slope crude oil and Gulf of Mexico crude in warm water at the Navy and Coast Guard Joint Marine Test Facility near Mobile, Ala. Cold-water testing is underway. Researchers also are analyzing residue of material that remains after burning.

Researchers during tests have shaken the powdery material onto water surfaces or spread it with a modified leaf blower. In the real world, Bonheyo suggested, it might be dispersed the way powdery materials are distributed by crop dusters.

TribLIVE commenting policy

You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.

We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.

While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.

We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers

We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.

We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.

We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.

We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.