Title : EOR feasibility in Mexico´s naturally fractured carbonate reservoir through microfluidics technology
Abstract:
With regards to improving recovery, displacement of oil from naturally fractured carbonate reservoirs faces several challenges. High heterogeneity throughout the geological structure and complex fluid flow behavior between the fractures and matrix hinders efficient recovery. In the scope of this work, we developed a micromodel of a real field, representative of reservoirs in Southern Mexico to experimentally evaluate the feasibility of chemical EOR application through screening of chemical formulations. The scarcity of core material poses challenges towards the diversity of experimental programs. Laboratory screening of EOR methods requires significant core material which can be tested to properly define properties and mechanisms governing oil displacement within a porous medium. Additionally, recreating high-pressure and high-temperature reservoir conditions is another obstacle in evaluating EOR methods. Thus this work demonstrates an alternative approach for the development of smart EOR solutions involving the incorporation of microfluidics technology. Available core samples from a naturally fractured carbonate reservoir were utilized to create the world’s first fractured micromodel. Reservoir conditions were recreated in the experimental setup, thus considering impact of pore network geometries, temperature and fluid compositions. The unique design and construction allows for visual observation of fluid-fluid interactions, and permits for a deeper understanding of topics such as fluid flow through fractures, snap-off and trapping effect, interfacial tension reduction, wettability alteration, matrix adsorption, and sweep efficiency between the systems fluids. Furthermore, micromodels can be easily cleaned and re-used, accelerating the screening workflow and significantly reducing experimentation costs. This work summarizes the chemical screening process, using a chemical surfactant, while using a ¨first of its kind¨ naturally fractured carbonate chip.
