Enhanced oil recovery by polymer-coated nanoparticles

Use of nanotechnology to the enhanced oil recovery (EOR) from
underground reservoirs

The project

The overall objective of the proposed work is to optimize the properties of polymer-coated nanoparticles (PNPs) toward the mobilization of residual oil from reservoir rocks. PNP-based aqueous suspensions, emulsions, and foams will be prepared, and tested as chemical flooding agents in porous media models (glass etched pore networks & sandpacks), and core plugs of reservoir rocks. Based on EOR studies, the synthesis and properties of PNPs will be tuned successively by a scheme of “adaptive control” (feedback) to select the most efficient and cost-effective PNP (“smart”) fluids. A numerical simulator of the multiphase flow and transport of “smart fluids” in digital porous media reconstructed from 3D CT-scan micro-tomographic images of reservoir rocks will be developed / calibrated / validated.

inspect the objectives

Technical Objectives

The specific technical objectives are described in detail below

Development of polymer-coated nanoparticles (PNPs)

by grafting adequately synthesized polymers to the surface of nanoparticles so that their colloidal stability/longevity is optimized. Various types of polymer coatings and PNPs (Comb-type copolymers, diblock copolymers, Post-modification of nanoparticles, plant extracts) will be synthesized by various pre-grafting or post-grafting routes and their stability in the aqueous phase will be assessed.

Development of oil-in water Pickering emulsions and CO2 foams by using the PNPs

as stabilizing agents and testing in-situ methods of emulsification and foaming. The possibility of PNPs to stabilize Pickering O/W emulsions and CO2 foams will be evaluated with the characterization of surface/interfacial and foaming/emulsification properties of different PNPs.

3. Correlation of the stability & longevity of PNP-based suspensions / emulsions / foams with the composition

of the aqueous medium. Testing the stability and longevity of PNP- suspensions /emulsions/foams by varying the composition of the aqueous medium and placing emphasis on adverse conditions of harsh environment (high salinity, high concentration of divalent cations). Theoretical interpretation of the interfacial properties of PNP-based multifluid systems.

Correlation of the PNP properties with their capacity to mobilize oil ganglia

from glass-etched pore networks and sandpacks. Testing the leaching potential and capacity of various PNP-fluids (suspensions, emulsions, foams) to mobilize trapped oil ganglia from glass-etched pore networks and sandpacks, under varying conditions.

Correlation of the PNP properties

(nanoparticle type/ polymer type/ composition of aqueous phase) with the EOR efficiency in reservoir cores. Measuring the efficiency of residual oil recovery by injecting PNP-fluids in well-characterized core plugs of varying permeability.

Numerical modeling of multiphase PNP-nanofluid transport in 3D pore networks

reconstructed from CT-tomographic images of reservoir rocks. All information extracted from experimental work will be exploited to develop/validate true-to-mechanism numerical models of oil displacement by nanofluids in 3-D reconstructed pore networks.