PVT Cell
Tuesday, April 26, 2016

Story by Tony Hunt

- April 26, 2016

Dr. Russell Johns and his research team have secured a $1.4 million grant with the Abu Dhabi National Oil Company to revolutionize modeling of alkali-surfactant-polymer (ASP) flooding. This research will be conducted at Penn State and will include the purchase of a $610,000 high pressure PVT cell for phase behavior experiments with surfactants.

Alkali-surfactant-polymer flooding injects surfactant to lower interfacial tension between the oil and brine so that oil is mobilized and recovered by production wells.   The phase behavior of this process is not well understood and has yet to be mathematically predicted. Dr. John’s research group has developed a new way to predict the microemulsion phase behavior that results from injection of surfactants and alkali.  Alkali is used to generate soaps and reduce adsorption of the injected surfactants to lower cost. Dr. Johns explained that in the U.S. alone, there is, on average, roughly 60% of the total estimated amount of oil still trapped in reservoirs by capillary forces across the nation. A more efficient form of oil recovery by the ASP process could create an unprecedented method to be implemented around the world for highly efficient oil recovery. The approach must be accurately modeled however.

Phase Behavior Diagram

Using the ASP flooding technique, Dr. Johns and his team are using the new partnership with ADNOC to obtain equipment and perform experiments in order to create and validate their new equations-of-state model. With the help of the new tools that the team has been researching for two years, they will be able to explore the effectiveness of ASP flooding not only in a small lab setting, but test the process across varying temperature and pressure gradients.

Dr. Johns explains that the current models used in the oil recovery industry don’t use an equations-of-state (EOS), and therefore cannot effectively predict or design the ASP process because significant gradients in variable like temperature and pressure exist within the reservoir. Dr. Johns and his team at the Energy Institute are hoping their research will develop a practical equations-of-state (EOS) to model microemulsion phase behavior that forms when surfactants and alkali are injected into petroleum reservoirs. “A robust algorithm is desired to predict the phase compositions ad phase amounts that form in situ,” Dr. Johns explains, “and then develop a new chemical flooding simulator that can predict recoveries from alkali-surfactant-polymer flooding.”