Previous posts on Talktothegreen have featured these three themes:
- "Depleted" oil fields.
- Microbes and
- feeding microbes
This item touches on all of these areas.
Newswise — Lewis Brown continues to devote much of his more than 40 years in petroleum microbiology figuring out how to squeeze more petroleum out of abandoned or soon-to-be-abandoned oil fields.
The Mississippi State researcher already has extended the life of one field by 17 years. That may sound far-fetched for those unfamiliar with his ongoing research that involves the forced growth of oil-chasing microbes used to redirect injected water that, in turn, sweeps once-inaccessible oil from old wells into production.
Brown said two-thirds of all U.S. oil remains in the ground because it’s not economically feasible to remove with existing technology. "We’ve now developed a method to get some of that oil out of the ground," he added. …
Historically, few in the industry had expertise related to microbiology, Brown explained. While much field research had focused since the 1940s on "microbial enhanced oil recovery" –known commonly by the acronym MEOR–few in the industry accepted the associated methodology for fear of plugging the wells. The few trials that were conducted didn’t last long enough to determine any long-term effects associated with the process, he explained.
The difference between Brown’s method, called microbial permeability profile modification, and most MEOR methods is that Brown only injects plant nutrients. Most MEOR processes involve injecting microorganisms.
By feeding only indigenous microbes in the oil-bearing formations, Brown avoids problems that can plug the wells. While limiting the amount of environmentally friendly nutrients limits their growth, it successfully alters the paths of injected water used to sweep the hiding oil from previously untouched areas.
In addition to being environmentally friendly, the process is cost-effective, Brown observed. In a recent field trial, the additional cost of the process was just $1.32 per barrel of new oil.