OU PROFESSOR FINDS WAY TO RECOVER TRAPPED OIL

NORMAN – Michael McInerney, a University of Oklahoma George Lynn Cross Professor in the Department of Botany and Microbiology, along with a team of botany and microbiology researchers, has demonstrated the technical feasibility of using detergent-producing microorganisms to recover trapped oil from oil reserves. He recently presented the group’s paper, “Biosurfactant-Mediated Oil Recovery Is Technically Feasible” at the American Society for Microbiology meeting held in Orlando, Fla.

Large amounts of oil are trapped in reservoirs across the globe. According to the U.S. Department of Energy, more than 300 billion barrels of oil remain in domestic reservoirs alone, which previous technologies have not been able to extract.

“Given the unlikelihood of discovering new, large oil resources it is critical that technologies be developed to exploit oil resources that exist in known reservoirs to help meet the increasing world demand for oil,” McInerney said.

Previous laboratory experiments have shown that detergent-like molecules, also known as biosurfactants, made by various species of Bacillus, recover over 40 percent of trapped oil from sand-packed columns and sandstone if the concentration of biosurfactants is more than 60 milligrams per liter.

McInerney and his team decided to conduct an experiment outside of the laboratory to see if they could get similar results to those previously reported in a lab.

A combination of two Bacillus strains and a food mixture of sugar, nitrate and minerals were added to two wells. Two control wells received only the food and a third control well received only water. After a four-day incubation period, samples were taken and tested from each well.

McInerney’s team discovered the wells containing the Bacilli and food mixture had produced detergent levels of 90 milligrams per liter, with a maximum concentration as high as 350 milligrams per liter, far exceeding the amount of biosurfactant needed to recover entrapped oil.

“We now know that the microorganisms will work as intended in the oil reservoir,” McInerney said. “The next important question is whether our approach will recover entrapped oil economically.”

He said the cost of the process could be less than one dollar per barrel of oil but that they need to measure oil production more precisely to be certain.