In an ongoing effort to maximize the value of the Nation’s oil resources, the U.S. Department of Energy (DOE) and its partners are investing in the first-ever polymer flood field pilot on the Alaska North Slope (ANS). To increase the amount of oil recovery on the ANS, DOE has invested approximately $7 million in a five-year effort to evaluate polymer flood technology and its application to heavy oil enhanced oil recovery in Alaska. Since the project began in August 2018, DOE has monitored the performance of the pilot in the injection wells.
A few of the project’s recent accomplishments include:
- Reducing water cut. The ratio of produced water to total volume of liquid produced has been reduced to approximately 15 percent. High water cut means less oil is being produced. Low water cut means more oil is being produced. The reduction of water cut means that the polymer is effective in moving more oil toward the production well.
- Eliminating unexpected injectivity issues or polymer breakthroughs. One potential problem in water flooding is the need to inject large volumes of fluids into the reservoir; this challenge is effectively addressed by polymer flooding. Further, no polymer has broken through the flood front. This means the waterflood front is moving fairly uniformly through the reservoir and effectively sweeping the oil toward the well without fingering through the flood front and creating flow paths that can bypass the oil.
- Increasing the oil rate by approximately 700 barrels per day over oil rate production prior to injection of the polymer. This means that oil production waterflood with polymer is far more effective than waterflood without polymer.
Polymer flooding is an enhanced oil recovery method that uses polymer solutions in an aqueous medium to increase oil recovery by decreasing the water−oil mobility ratio.
This type of project can be applied to basins with heavy oil and to basins with oil containing a viscosity of 1-5 centipoise. This means that heavy oil reservoirs on the ANS with very high viscosity—and possibly those in the lower 48 states—can benefit from the addition of this system or similar polymer systems to their conventional waterflood operations.
“These are a few examples of the insights that can be gained from DOE’s basin-specific research strategy,” said Assistant Secretary for Fossil Energy Steven Winberg. “We expect many more successes from each of our 17 Field Laboratories, especially when coupled with the analysis of the data generated at these field site projects.”
In collaboration with DOE, the polymer flood field pilot on the ANS is led by the University of Alaska Fairbanks in partnership with Hilcorp Alaska LLC, the University of Missouri, the New Mexico Institute of Mining and Technology, and the University of North Dakota’s Energy & Environmental Research Center.
For more information on the ANS Field Laboratory, visit DOE’s National Energy Technology Laboratory website.