Novomer’s polymers are an economical and unique surfactant solution for creating a stable CO₂ foam for enhanced oil recovery (EOR). They consist of a scCO₂-philic polycarbonate polymer tail and an easily added hydrophilic end group (or head). The design of Novomer’s surfactants have the potential to enable more cost effective and higher yielding CO₂ EOR and thus expand the application of this important oil production technology.

Our research, in collaboration with the University of Pittsburgh, has indicated that low molecular weight polypropylene carbonate readily dissolves in scCO₂ at typical oil reservoir conditions. Historically, the high cost of manufacturing PPC has caused it to be ignored for use in EOR applications. Today, however, Novomer’s innovative and patented catalyst system and flexible PPC technology platform allows the creation of a new generation of cost effective, high performance EOR surfactants.

Standard oil production today takes place in three phases.

1. Primary Recovery – Oil is forced to the surface by the natural pressure released during the initial drilling operation. Typically 12% to 15% of a deposit’s original oil in place (OOIP) is captured at this stage.
2. Secondary Recovery – Water flooding is used to force oil from the deposit and typically recovers an additional 6% to 30% of the OOIP.
3. Tertiary Recovery – Also known as enhanced oil recovery, utilizes other complex and more costly methods to capture an additional 10% to 40% of OOIP beyond primary and secondary recovery.

One of the current tertiary recovery methods used for EOR is called the “Water Alternating Gas” (WAG) process. WAG suffers from inefficiencies due to the low viscosity of scCO₂, which, as a result, requires huge quantities of CO₂ to be used and limits the amount of oil that can be recovered. Identification of cost effective, environmentally friendly materials that dissolve in scCO₂ for use in EOR has been the subject of extensive research. Supercritical CO₂-philes (materials soluble in scCO₂) are rare and use of these materials as surfactants was not possible due to the high pressures required to dissolve them (a result of their high molecular weight) and the inability to cost-effectively add a hydrophilic group for solubility in the bulk recovery fluid (water). Novomer's PPC technology is well suited to address both challenges.

Source: Department of Energy