Research could lead to improved oil recovery, better environmental cleanup

August 02, 2012

CORVALLIS, Ore. - Researchers have taken a new look at an old, but seldom-used technique developed by the petroleum industry to recover oil, and learned more about why it works, how it could be improved, and how it might be able to make a comeback not only in oil recovery but also environmental cleanup.

The technology, called "microbial enhanced oil recovery," was first developed decades ago, but oil drillers largely lost interest in it due to its cost, inconsistent results and a poor understanding of what was actually happening underground.

The new findings by engineers at Oregon State University, published in the Journal of Petroleum Science and Engineering, could help change that. This may allow the oil industry not only to produce more oil from their existing wells, but also find applications in cleaning up petroleum spills and contaminants.

"This approach of using microbes to increase oil recovery was used somewhat in the 1980s when oil prices were very high, but the field results weren't very consistent and it was expensive," said Dorthe Wildenschild, an associate professor in the OSU School of Chemical, Biological and Environmental Engineering. "It's seldom used now as a result."

Oil drilling has always been difficult - it's not as simple as drilling a hole and watching the petroleum gush out of the ground.

That may happen for a while, but as a secondary step, water is often injected into the well to help flush out more oil. Such production techniques generally recover only one-third to one-half of the oil originally present in a reservoir.

A third approach sometimes used after water injection is to inject microbes into the well and "feed" them with sugars such as molasses to encourage their growth. This can clog some pores and in others has a "surfactant" effect, loosening the oil from the surface it clings to, much as a dishwasher detergent loosens grease from a pan.

"By clogging up some pores and helping oil move more easily through others, these approaches can in theory be used with water flushing to help recover quite a bit more oil," Wildenschild said.

The surfactant can be man-made, or microbes can be used to produce it at a lower cost. However, getting a particular culture of microbes to produce the biosurfactant under harsh field conditions is tricky.

"It's complicated, you have to use just the right microbes, and feed them just the right foods, to accomplish what you want to do," Wildenschild said.

In OSU laboratory experiments, Ryan Armstrong, a recent doctoral graduate at OSU, found that the clogging mechanism is the simplest and most effective approach to use, although combining it with the biosurfactant technology achieved optimal oil recovery.

A better fundamental understanding of this process - along with higher oil prices that better reward efforts to recover more oil - could lead to renewed interest in the technology on a commercial basis, the OSU researchers said, and make oil recovery more productive. As an extra benefit, the concepts might also work well to help remove or clean up underground contaminants, they said.
-end-
This work was supported by the Petroleum Research Fund of the American Chemical Society.Editor's Note: A digital image demonstrating improved oil recovery is available online: http://bit.ly/QfX2VV

Oregon State University

Related Microbes Articles from Brightsurf:

A new look at deep-sea microbes
Microbes found deeper in the ocean are believed to have slow population turnover rates and low amounts of available energy.

Microbes might manage your cholesterol
Researchers discover a link between human blood cholesterol levels and a gene in the microbiome that could one day help people manage their cholesterol through diet, probiotics, or entirely new types of treatment.

Can your gut microbes tell you how old you really are?
Harvard longevity researchers in collaboration with Insilico Medicine develop the first AI-powered microbiomic aging clock

What can be learned from the microbes on a turtle's shell?
Research published in the journal Microbiology has found that a unique type of algae, usually only seen on the shells of turtles, affects the surrounding microbial communities.

Life, liberty -- and access to microbes?
Poverty increases the risk for numerous diseases by limiting people's access to healthy food, environments and stress-free conditions.

Rye is healthy, thanks to an interplay of microbes
Eating rye comes with a variety of health benefits. A new study from the University of Eastern Finland now shows that both lactic acid bacteria and gut bacteria contribute to the health benefits of rye.

Gut microbes may affect the course of ALS
Researchers isolated a molecule that may be under-produced in the guts of patients.

Gut microbes associated with temperament traits in children
Scientists in the FinnBrain research project of the University of Turku discovered that the gut microbes of a 2.5-month-old infant are associated with the temperament traits manifested at six months of age.

Gut microbes eat our medication
Researchers have discovered one of the first concrete examples of how the microbiome can interfere with a drug's intended path through the body.

Microbes can grow on nitric oxide
Nitric oxide (NO) is a central molecule of the global nitrogen cycle.

Read More: Microbes News and Microbes Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.