Chemical Method to Improve CO2 Flooding Sweep Efficiency for Oil Recovery using SPI-CO2 Gels

The capture and use of carbon dioxide (CO2) from industrial plants for use in CO2 flooding of marginal oil reservoirs provides a dual use opportunity prior to final CO2 sequestration in the depleted reservoir. Miscible CO2 flooding processes greatly increase the recovery of crude oil from a reservoir compared to recovery normally seen with water flooding. However, the problem with CO2 flooding lies with the low sweep efficiency of CO2, because of its substantially higher mobility relative to the crude oil. This mobility promotes fingering and early breakthrough of the CO2. This project will develop a SPI gel system to mitigate the sweep efficiency problem in CO2 flooding. Phase I will evaluate gel time, gel strength, and gel stability using static and dynamic testing. A large-scale CO2 flood field test will be conducted in Phase II. Commercial Applications and other Benefits as described by the awardee: The new gel system would add over 400 million barrels of otherwise bypassed reserves in ten years, valued at $20 billion ($50/bbl). These reserves would be produced without the addition of a single well or any environmental risk.