Disrupting an Oil Spill's Toxic Journey

Written by: Tracey Regan,

Contamination from oil spills cascades through the environment, inundating plants and animals upon release before drifting into ecosystems, sometimes hundreds of miles away, and sinking into sediment where it is difficult to reach and remediate. Each phase of this toxic journey demands its own urgent remedy.

Graduate engineering students Feng Gao and Brian Wartell are tackling pollution at different points along the route. Gao, a Ph.D. student in mechanical engineering, is modeling methods for applying dispersants directly after a spill to break the oil down as quickly as possible. Wartell, a Ph.D. student in environmental engineering, is studying ways to stimulate the growth of bacteria capable of digesting petrochemicals that are buried in anaerobic sediment on land and in river beds.

Both students were awarded scholarships to attend the recent International Oil Spill Conference – a triennial forum on prevention and response sponsored by federal agencies, energy companies and maritime organizations – to present research they’re conducting at NJIT’s Center for Natural Resources Development and Protection, whose director, Michel Boufadel, advises them.

“Dispersants are a hot topic. Researchers are looking for better ways to apply them to maximize their effectiveness, while minimizing the impact on the natural environment,” says Feng, who studies the hydrodynamics of underwater releases and the effect of dispersants, which break up oil slicks into smaller droplets that mix more easily with water and are better absorbed by the natural environment.

Feng gave a talk on methods for tracking the trajectory of oil droplets following a deep water blowout and a poster presentation on their behavior following the application of dispersants. 

“My research shows how dispersants reduce surface tension, causing oil to peel away from a droplet. This is known as ‘tip-streaming,’ which affects the size distribution and behavior of oil droplets in water,” he explains. 

Wartell focuses primarily on the remediation of polycyclic aromatic hydrocarbons (PAHs), a common component of crude oil that is harmful to the environment and human health and is especially resistant to degradation under anaerobic conditions.

“Oil pollution can be deep within the sediment or in far-reaching ocean plumes, and while its components often biodegrade aerobically within a year, deeply buried oil can reside in an anaerobic environment for decades,” he notes, adding that his primary objective is to create the optimal conditions for microorganisms to break down these petrochemicals.

“Research has shown that bacteria and archaea, which are microbes, have the ability to degrade oil components such as alkanes and single ring aromatics, but less readily biodegrade PAHs, which are very toxic and mutagenic,” he says. “I’m looking at ways to either introduce oxygen into the subsurface to transform the environment into an aerobic one or to introduce sulfate, which many anaerobic bacteria respire rather than oxygen, to increase growth and metabolism rates.”

The conference, Feng said, is a forum designed to bridge the gap between the academic and business sectors – to promote research that is targeted and effective and prevention and clean-up methods that are based on scientific evidence. Both sides are eager to harness the talents of young, innovative thinkers.

“Oil spills and their impacts will continue for a long time, as will remediation efforts,” Wartell notes. “Young people familiar with emerging technologies and the ability to take new approaches to existing problems will be critical.”