Design and analysis of different models of microfluidic devices evaluated in enhanced oil recovery (EOR) assays

Abstract

Microfluidic devices are a new platform for Enhanced Oil Recovery (EOR) assays. The application of Colloidad Dispersion Gels (CDG) injection method has been proposed in recent years. However, the mechanism of oil recovery enhancement has not been completely elucidated. Its purpose is to mobilize oil by decreasing the permeability of channeled zones. The success of injection depends on the characteristics of water, the porous medium and the oil. Therefore, a successful injection in a reservoir can be different in another, hence the importance of a methodology for assessment prior to injection. This work applies micro and nanotechnology techniques to develop microfluidic chips used in EOR tests. EOR chips simulate the phenomena that occur in micro-nano scale reservoirs. Experiments analyzed multiphase flows in porous media inside chips. Generally, the first step of the experiments corresponds to fill the microchannels with water and then oil (1 poral volume 1PV). Second, water-injection takes place at constant flow rate until oil recovery ceases. Finally, either polymer or CDG is injected and their behavior is studied by digital image analysis. Results allowed obtaining graphs of oil residual saturation versus time for pore volumes of fluid used in EOR. The optimum configurations of the microchannels showed 80% of residual oil saturation after water injection.