Increased Oil Production With Something Old, Something New

Abstract

Pumping is stopped to allow a pressure test to see if the formation will allow free movement of chemicals used to free the remaining oil in this old Oklahoma field. Enhanced oil recovery (EOR) has become fertile ground for emerging—and re-emerging—technologies. Emerging from laboratories are materials based on nanotechnology that could change what is possible with aging reservoirs. Researchers are working on making carbon dioxide foams built to last, time-release coatings to deliver gels deep into reservoirs, and tracers for real-time waterflood tracking. Re-emerging are chemical EOR methods that have been around for 30 years but whose development was stunted by a long stretch of low oil prices. Higher prices are now inspiring a second look at EOR methods, taking advantage of advances in chemistry and computing to create cost-effective ways to rework underperforming old fields. “It didn’t happen when the technology stopped developing in the 1980s,” said Jeff Harwell, a professor at the University of Oklahoma, who has been a catalyst for this re- emerging technology. “My perception is we are just to the point in the industry where oil prices have risen to the level where it is economic.” Continued oil prices near USD 100/bbl makes EOR an attractive possibility—the estimated cost to produce plus the profit margin needed to justify the risk is about USD 60/bbl, Harwell said—but, for the many independents that own older fields, the cost of reducing salinity levels in their fields in order to use the available chemicals has been prohibitively high. Harwell said he and others he knew in EOR realized that, while the economics once again favored it, work was needed to make EOR a realistic option for small and mid-sized operators whose budgets and appetite for risk are both limited. They worked with chemical companies to develop improved surfactants that worked without having to make costly modifications to fields, improved techniques for analyzing and planning EOR projects to increase the chance of success, and started a company to demonstrate what they could do. He is not alone. Harwell pointed out that others, such as Gary Pope, a professor at The University of Texas at Austin, whom he describes as the EOR guru, is working with a chemical company to create improved surfactants. Big EOR service providers, such as Tiorco and Surtek, are also working on new things. It is a tough sell, but one with big potential. In Oklahoma, only 14 billion bbl of the 82 billion bbl in the ground have been produced, he said. Many fields date back to the early days of oil exploration when the focus was on pumping oil as fast as possible. “It was really before petroleum engineering was a discipline,” Harwell said. Production was limited by early over-production and poorly done waterflooding experiments, adding to the petroleum engineering expertise required to rework these fields.