InterPore2026

Multiscale Interfacial Pinning of Nanomaterials Governing Relative Permeability Modification in Heterogeneous Porous Media

21 May 2026, 10:05

1h 30m

Poster Presentation (MS06) Interfacial phenomena across scales Poster

Speaker

Ming Qu (Northeast Petroleum University Sanya Offshore Oil and Gas Research Institute)

Description

Heterogeneity in reservoir porous media causes injected fluids to preferentially flow through pathways of least resistance, resulting in uneven pore-scale displacement and severe flow imbalance along the reservoir profile. This phenomenon significantly reduces sweep efficiency and limits oil recovery. Polymer-based gels are commonly used for water shutoff; however, in low-permeability reservoirs or small pore throats within medium- to high-permeability formations, such gels cannot effectively penetrate the pore space. In addition, their strong retention and bulk plugging behavior often reduce the permeability of all fluid phases, leading to irreversible formation damage and loss of oil productivity.
Relative permeability modifiers (RPMs) offer an alternative approach by selectively regulating multiphase flow rather than physically blocking pore space. Existing RPMs are predominantly polymer-based and still suffer from non-selective permeability reduction. Although nanomaterial-based RPMs have attracted attention due to their small size, their weak interfacial adhesion often results in desorption and washout under dynamic flow conditions, limiting their long-term effectiveness.
To overcome these challenges, a nanomaterial-based RPM (PDA NanoRPM) with combined strong adsorption and hydrophobic functionality was developed. Single-layer molybdenum disulfide nanosheets with high specific surface area were employed as the carrier, onto which dopamine (DA) was grafted. Under alkaline conditions, DA undergoes spontaneous self-polymerization to form a polydopamine (PDA) coating rich in catechol and amine groups. These functional groups enable strong adhesion to mineral surfaces through hydrogen bonding, metal coordination, and π–π interactions, thereby inducing pronounced interfacial pinning at both solid-fluid and oil-water interfaces. Moreover, the PDA coating serves as a universal secondary reaction platform, allowing further grafting of hydrophobic moieties to achieve simultaneous strong adsorption and hydrophobicity[1, 2].
Flow redistribution and displacement behavior were investigated using heterogeneous microfluidic chips and sand-packed single-well models. After treatment with a 0.5 wt% PDA NanoRPM, injected fluids exhibited clear flow diversion away from high-permeability channels, enhancing oil displacement from smaller and previously unswept pores. Core flooding experiments combined with in situ CT imaging revealed that the relative permeability of the water phase decreased by approximately 10%, while the oil relative permeability increased by about 9%, compared to untreated cores. Notably, no measurable change in absolute permeability was observed.
CT-derived Hounsfield Unit (HU) distributions became significantly more uniform after treatment, indicating reconstruction of the internal flow field in heterogeneous porous media. During subsequent water flooding up to 10 pore volumes, no evident water breakthrough channels or abrupt water-cut increases were detected, demonstrating the strong adsorption stability and sustained effectiveness of the PDA NanoRPM.
This study demonstrates that PDA NanoRPM modify relative permeability through interfacial pinning rather than bulk pore plugging. The proposed strategy provides new insights into multiscale interfacial phenomena governing selective water control and oil transport, offering a promising pathway for durable and damage-free RPM applications in heterogeneous reservoirs.