Chemical Enhanced Oil Recovery (EOR) technologies include polymer, alkaline, surfactant injection and any combination of those. One of the main chemical EOR process is surfactant flooding whose key mechanism is the interfacial tension (IFT) reduction between oil and the displacing fluid. The IFT reduction is associated to the increase of capillary number, which is the dimensionless ratio of viscous-to-local capillary forces. Therefore, as IFT is reduced through the addition of surfactants, the ultimate oil recovery is enhanced.
The purpose of this work is the design of a systematic methodology to evaluate already existing products as well as new ones that are typically used for wells cleaning or damage removal, to be applied for Chemical Enhanced Oil Recovery. Solutions at different concentrations were prepared in synthetic brine. The behavior of these solutions at room and reservoir temperatures was observed. Quick Scans (qualitative method) were performed to evaluate the decrease of the IFT with two crude oils from Argentina basin; and the IFT was measured with a Spinning Drop Tensiometer.
According to some previous consulted literature, enzymatic, terpenic and surfactant products should present an intermediate recovery between a polymer flooding and ASP / SP processes. To understand how this recovery works, flow tests using 80 microns glass beads were carried out. These results led to an approximated recovery factor applying flooding of these chemicals.