Contact: Bob Ratliff
Microscopic organisms are helping Mississippi State University scientists keep oil wells producing long after their expected lifespan.
Called microbially enhanced oil recovery, the process is the focus of microbiologist and researcher Lewis R. Brown. It began with a class he taught three decades ago.
In a 1960s microbiology course, Brown presented the theory that "feeding" microbes already present in oil reservoirs could revive dying fields. Then-student Don Stacy, who would go on to complete a doctorate in petroleum engineering, recalled the lecture. While serving as Amoco Corp.'s vice president for research in 1979, Stacy called his former professor to ask more about the theory.
"He asked me to do a presentation at company headquarters in Tulsa," Brown said. "A couple of weeks later, the company provided $50,000 to fund the research."
The study eventually led to a patented process and another grant-this time for $500,000 from the U.S. Department of Energy.
Later, MSU engineering professor Alex Vadie would join the research effort and target 350 billion barrels of oil reserves that could not be recovered using current technology.
Brown said wells normally are drilled into pockets of oil-bearing strata. Natural pressure, which forces the black liquid to the surface, eventually drops and the flow stops. To recover more, producers can pump in water to "sweep" oil to the surface, but water erodes channels and again stops flow. It's then that microbes can play a role.
"Microbes in the reservoir are dormant because they don't have the required nutrients," Brown said.
The MSU team adds nitrogen- and phosphorus-containing nutrients to the injection water. Feeding on those materials and carbon in the oil, the microbes, in a process that provides both economic and environmental benefits, grow and selectively plug the more porous channels. This allows the pumped water to sweep oil from new areas of the reservoir.
In 1990, MSU alumnus James Stephens, vice president of Jackson-based Hughes Eastern Corp., asked the team to apply its findings to a Lamar County, Ala., field scheduled to be abandoned with two-thirds of its oil still in the ground.
The scientists and Hughes Eastern eventually won a five-and-half-year, $3.8 million DOE contract to demonstrate the process. More than 100,000 barrels of additional oil since have been recovered.
The field is expected to produce for another 5 to 10 years and yield 400,000 more barrels worth approximately $6 million at today's prices.
The Hughes Eastern project is receiving the 1999 Hart's Oil and Gas World Magazine Best Advanced Recovery Project Award for the Gulf South area.
Brown, Vadie and Stephens each received a letter of congratulations from U.S. Secretary of Energy Bill Richardson, who said the project is making an "important contribution to maintaining domestic oil and gas production capacity that is vital to our nation's energy security."
To further refine the process, Mississippi State recently received a three-year, $935,000 DOE contract. Chemist Charles U. Pittman Jr. has joined Brown and Vadie for this phase of the research.
Brown said an additional benefit of the project is that more than 40 MSU graduate and undergraduate students have gained valuable experience and financial support from work on the biotechnology research.