Surface Charge Affecting Fluid–Fluid Displacement at Pore Scale

Advanced Materials Interfaces, vol. 9

Abstract

Abstract Efficiency in fluid–fluid displacement is drastically reduced by viscous fingering, limiting the overall effectiveness in enhanced oil recovery, membrane science, and lateral flow devices used in biomedical applications. Local instabilities at the fluid–fluid interface lead to finger‐like patterns when a less viscous fluid displaces an immiscible fluid of higher viscosity. This widely observed phenomenon in multiphase flow inside porous media is infamously intricate to control, especially for given geometry and viscosity ratio. The presented study uses a highly controlled microfluidic porous network structure with tailored ionic surface strength. The direct correlation of viscous fingering evolution on the porous structure's zeta potential at a pore‐scale level is demonstrated via polyelectrolyte coatings using a layer‐by‐layer technique. Displacement patterns are tuned from vigorous viscous fingering over stable displacement to corner flow events across a broad range of capillary numbers depending on the applied coatings. The experimental data show an increasing trend of oil recovery with increasing surface wettability, consistent with several previous findings. Furthermore, the results reveal that surface zeta potential correlates positively with recovery rate but negatively with the displacement stability quantified by the fractal dimension. These insights enable a more targeted porous media design to obtain optimal multiphase flow control.

Authors 7

1. Anna Maria Kalde Aachen

   DWI – Leibniz Institute for Interactive Materials

   Affiliation as printed

   DWI‐Leibniz—Institute for Interactive Materials Forckenbeckstrasse 50 52074 Aachen Germany

2. Sophia Lippold Aachen Chemical Process Engineering

   RWTH Aachen University

   Affiliation as printed

   Chemical Process Engineering RWTH Aachen University Forckenbeckstrasse 51 52074 Aachen Germany

   Chemical Process Engineering RWTH Aachen University Forckenbeckstrasse 51 52074 Aachen Germany

3. Jonas Lölsberg Aachen

   DWI – Leibniz Institute for Interactive Materials

   Affiliation as printed

   DWI‐Leibniz—Institute for Interactive Materials Forckenbeckstrasse 50 52074 Aachen Germany

4. Ann‐Kathrin Mertens Aachen Chemical Process Engineering

   RWTH Aachen University

   Affiliation as printed

   Chemical Process Engineering RWTH Aachen University Forckenbeckstrasse 51 52074 Aachen Germany

   Chemical Process Engineering RWTH Aachen University Forckenbeckstrasse 51 52074 Aachen Germany

5. John Linkhorst Aachen Chemical Process Engineering

   RWTH Aachen University

   Affiliation as printed

   Chemical Process Engineering RWTH Aachen University Forckenbeckstrasse 51 52074 Aachen Germany

   Chemical Process Engineering RWTH Aachen University Forckenbeckstrasse 51 52074 Aachen Germany

6. Peichun Amy Tsai corresponding

   University of Alberta

   Affiliation as printed

   Department of Mechanical Engineering University of Alberta Edmonton Alberta T6G 2G Canada

   Department of Mechanical Engineering University of Alberta Edmonton Alberta T6G 2G Canada

7. Matthias Weßling corresponding Aachen Chemical Process Engineering

   DWI – Leibniz Institute for Interactive Materials · RWTH Aachen University

   Affiliation as printed

   Chemical Process Engineering RWTH Aachen University Forckenbeckstrasse 51 52074 Aachen Germany

   DWI‐Leibniz—Institute for Interactive Materials Forckenbeckstrasse 50 52074 Aachen Germany

   Chemical Process Engineering RWTH Aachen University Forckenbeckstrasse 51 52074 Aachen Germany