Calcium Carbonate Coated Micromodels With Various Permeabilities for Study of Oil-Water Phase Behavior in Reservoir Rock Analogues

Abstract

Oil displacement are typically evaluated by core flood experiments using pre-cut cylindrical rock samples that are pre-saturated and aged with crude oil to restore reservoir conditions. Imaging pore-scale on an entire core during an oil recovery test is not possible and these experiments are lengthy and costly. Alternatively, micromodels with simplified porous microfluidic systems have been fabricated to mimic reservoir rock and visualize pore-scale fluid-reservoir rock interactions in real time. However, to demonstrate the precise control over the permeability of the micromodel structure is not trivial. We demonstrate a simple method to create micromodels with various permeabilities composed of CaCO₃ nanocrystals coating on borosilicate surfaces of microfluidic chips. The measured permeability of the fabricated chips was varying from 300 mD to 1900 mD. The oil-water phase behavior was studied using these micromodels with different permeabilities. The experimental procedure was performed by aging the micromodels with crude oil, flowing seawater and surfactant in seawater through the micromodel at a constant rate equivalent to 2.4 feet/day. This new architecture of calcium carbonate coated microfluidic chips with controlled permeability allows for better understanding of pore-scale fluid interactions in reservoir rock domains with various morphologies.

AAPG Datapages/Search and Discovery Article #90323 ©2018 AAPG Annual Convention and Exhibition, Salt Lake City, Utah, May 20-23, 2018