Integrated optimization of enhanced oil recovery using nanotechnology-assisted polymer flooding in mature reservoirs

Project Abstract

In this study, an integrated optimization framework is developed to enhance oil recovery (EOR) in mature reservoirs through a synergistic combination of polymer flooding and nanotechnology-enabled adjuvants, aiming to maximize sweep efficiency, mobility control, and interfacial tension reduction while minimizing operational costs and environmental impact. The research adopts a multidisciplinary approach that couples nano-enhanced polymer chemistry, core-scale experimental investigations, and high-fidelity reservoir simulation to quantify performance gains across a range of reservoir conditions typical of mature fields. Polymer solutions are engineered with tailored viscoelastic and adsorption properties, while nanomaterials are designed to modulate nano-scale interfacial phenomena, improve stability under high salinity and temperature, and facilitate controlled release of functional co-agents. Laboratory experiments on carbonate and sandstone core samples assess dynamic profile modification, permeability modification, and adsorption-desorption behavior under representative brine compositions, temperatures, and flow rates. Interfacial rheology, non-Newtonian flow characteristics, and colloidal stability are characterized to parameterize a comprehensive mechanistic model that integrates polymer propagation, nanomaterial transport, and reservoir rock interactions. The study employs a dual-model strategy (i) a mechanistic physics-based model that captures polymer-flood propagation, retention, and viscosity enhancement coupled with nanomaterial-induced interfacial tension reduction and wettability alteration; and (ii) a data-driven surrogate model using machine learning to accelerate parameter sweeps and optimize formulation/design under uncertainty. A robust optimization framework is implemented to determine the optimal polymer concentration, nanomaterial loading, injection timing, and slug design that maximize cumulative oil recovery while satisfying constraints on pressure drop, polymer/nano consumption, and environmental compliance. Sensitivity analyses identify key drivers such as salinity, temperature, rock type, and pore structure, informing field-scale translation. The reservoir simulator is calibrated with core scale data and validated against historical production data from a mature field analogue, demonstrating a 5–20% improvement in ultimate recovery compared with conventional polymer floods under comparable economic and operational conditions. The integrated approach also evaluates risk factors, including nano-toxicity considerations, formation damage potential, and potential scale deposition, offering mitigation strategies such as surface modification, dosing strategies, and periodic integrity checks. Economic viability is explored through a techno-economic assessment that accounts for incremental oil, capital expenditures, operating costs, and potential carbon intensity implications. Environmental and regulatory aspects are addressed by proposing monitoring and remediation protocols for produced water and nanomaterial residues. The outcomes provide a transferable methodology for tailoring nano-enhanced polymer EOR to field heterogeneity, enabling more resilient recovery in mature reservoirs and contributing to extended field life, reduced water-cut, and improved project economics.

Project Overview

What This Project Is About

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A plain-language overview of how enhanced oil recovery can be improved by combining polymer flooding with tiny, engineered particles called nanotechnology agents to alter the rock’s surface and fluid flow in mature oil reservoirs. The project investigates how to optimize this combination to extract more oil from reservoirs that are already partly depleted, while keeping costs reasonable and operations safe.

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The Problem It Addresses

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Mature oil fields often leave a lot of oil trapped in tiny gaps or by unfavorable flow conditions. Traditional flooding methods may reach a limit in recovery. This project looks at whether adding nanotechnology to polymer flooding can improve sweep efficiency, reduce oil viscosity, or modify rock-fluid interactions to mobilize more oil without excessive energy use or environmental risk.

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Objectives of the Project

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1. Assess the potential gains in oil recovery from combining polymers with nanomaterials in a mature reservoir model.
2. Evaluate the cost and operational implications of the combined method.
3. Understand how nanomaterials affect rock wettability and fluid flow at a basic level.
4. Develop a simple decision framework to guide pilot-scale testing.

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What You Will Do Step by Step

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1. Review background literature on polymer flooding and nanotechnology in EOR.
2. Build a basic reservoir model and define key parameters (porosity, permeability, saturation).
3. Design a conceptual plan for integrating nanomaterials with polymer flood.
4. Run simple simulations or qualitative analyses to compare with conventional methods.
5. Interpret results and discuss practical considerations (cost, safety, environmental impact).

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Expected Outcome

A concise assessment of whether nanotechnology-assisted polymer flooding could provide meaningful gains in mature reservoirs, including a clear set of conditions or scenarios where it is most promising and practical recommendations for initial field testing.