A method and system using polymer additives for dynamic homogenization of flow and transport in porous media

Background

In many industrial and environmental applications, such as enhanced oil recovery, geothermal energy extraction, and groundwater remediation, fluids are injected into subsurface porous rocks to extract resources or remediate contaminants. These underground reservoirs are rarely uniform; instead, they are often stratified, consisting of layers or fractures with widely varying permeability. This heterogeneity poses a significant challenge because injected fluids naturally follow the path of least resistance, rapidly channeling through high-permeability zones while bypassing lower-permeability regions. As a result, much of the reservoir remains untapped, leading to inefficient resource extraction, poor heat recovery, or incomplete contaminant removal. The need for technologies that can redistribute flow more uniformly across all strata is therefore critical for maximizing the effectiveness and sustainability of these subsurface operations.

Current approaches to address this challenge typically involve the use of diverters or precipitating agents that are introduced into the injection fluid to block or restrict flow in the high-permeability zones. While these methods can temporarily redirect fluids into less accessible areas, they suffer from significant drawbacks. Most notably, these diverters tend to irreversibly clog the targeted regions, permanently altering the reservoir’s structure and limiting future adaptability. This lack of dynamic control means that once the diverters are in place, operators cannot easily respond to changing reservoir conditions or optimize performance over time. Additionally, these methods may not be effective in highly dynamic or evolving environments, and the irreversible nature of clogging can hinder subsequent operations or even cause long-term damage to the reservoir. As a result, there is a pressing need for solutions that offer reversible, real-time control over flow distribution without causing permanent changes to the subsurface medium.

Technology

This technology provides a dynamic and reversible method for homogenizing flow and transport in stratified porous media by injecting an aqueous solution containing dilute, high molecular weight flexible polymers. When the injection fluid reaches a specific flow regime—quantified by the Weissenberg number—the polymers induce elastic turbulence selectively in high-permeability regions. This increases the local flow resistance, diverting the fluid into lower-permeability zones and thereby improving sweep efficiency and transport uniformity. The process is managed by a computational tool that models the reservoir’s stratification and the polymer solution’s rheological properties, enabling real-time optimization of injection parameters. The system comprises pumps, polymer reservoirs, and processors that dynamically adjust the injection conditions to maintain optimal flow distribution, and the process is fully reversible—flow partitioning can be tuned or reset simply by altering operational settings.

What differentiates this technology is its ability to provide adaptive, non-permanent control over subsurface flow without the drawbacks of traditional methods such as irreversible clogging or the need for physical diverters. Unlike Newtonian fluids, which cannot dynamically redistribute flow in heterogeneous media, the use of polymer-induced elastic turbulence allows for selective, tunable resistance that responds passively to local flow conditions. This approach is validated both experimentally and through modeling, demonstrating significant improvements in flow homogenization, resource extraction efficiency, and operational flexibility. Its reversibility, adaptability to changing reservoir conditions, and compatibility with standard injection infrastructure make it a transformative solution for enhanced oil recovery, geothermal energy extraction, and groundwater remediation, offering substantial gains in efficiency and resource utilization.

Benefits

• Improves sweep efficiency by dynamically diverting flow from high- to low-permeability zones in stratified porous media.
• Enables reversible and real-time control of flow partitioning without permanently clogging the reservoir.
• Enhances heat and mass transport uniformity, benefiting applications like geothermal energy extraction and groundwater remediation.
• Reduces the number of pore volumes required for effective resource extraction or remediation by up to 100 times compared to traditional methods.
• Utilizes a computational modeling tool to optimize polymer concentration and injection parameters tailored to reservoir characteristics.
• Passive mechanism triggered by elastic turbulence, requiring no additional chemical reactions or irreversible changes to the medium.
• Applicable to multiphase flows, improving mobilization of oil and contaminants after hydraulic fracturing or in heterogeneous reservoirs.
• Compatible with standard injection equipment augmented with polymer reservoirs and control processors for dynamic operation.

Applications

• Enhanced oil recovery optimization
• Geothermal heat extraction efficiency
• Groundwater remediation improvement
• Uniform chemical delivery in subsurface

Additional info

This method homogenizes transport in stratified porous media by injecting dilute, high molecular weight flexible polymers. It exploits elastic turbulence to increase nonlinear flow resistance in high-permeability regions at specific Weissenberg numbers. This diverts fluids into lower-permeability zones, improving sweep efficiency without permanent clogging. Integrated computational modeling uses reservoir descriptors and rheological properties to predict flow partitioning, enabling real-time, reversible control of transport uniformity across heterogeneous strata.