Overview of Polymer Flooding
Overview of Polymer Flooding. Polymer flooding is one of the most widely used Chemical Enhanced Oil Recovery (EOR) techniques, offering significant improvements in oil displacement efficiency, reduced water cut, and extended field life. Understanding its full scope—from theory to field application—is essential for optimizing project outcomes.
This page provides a collection of documents covering the entire spectrum of polymer flooding, including:
- Fundamental principles explaining how polymer flooding improves sweep efficiency.
- Technical reviews summarizing key research, field trials, and industry advancements.
- Guides and best practices for screening, design, and implementation.
- Case studies and field reports showcasing real-world applications and lessons learned.
You can also check our YouTube channel for additional videos and podcasts and navigate the Polymer Flooding Guide for more content or our Academy for online courses.
Table of Contents
Polymer Flooding - An Overview
We propose the slides from Randy Seright’s training course.
Polymer Flooding - Concept Overview
In this video, we demonstrate how Polymer Flooding enhances oil recovery by improving sweep efficiency and encouraging crossflow between reservoir layers. We also examine the impact of resuming water injection after polymer injection ends: due to unstable displacement, water preferentially flows through the high-permeability zones, bypassing the lower-permeability areas. As a result, without continued polymer injection, the mobility control is lost—and the effectiveness of the project rapidly declines
Publications - Polymer Flooding Overview
In the following section, we provide access to publications including Randy Seright’s.
This paper investigates the potential of various approaches for improving sweep in parts of the Daqing oil field that have been enhanced-oil-recovery (EOR) targets. Our studies indicated that the polymer flood should have provided excellent sweep throughout the vast majority of the patterns under consideration. However, because alkaline/surfactant/polymer (ASP) flooding is being considered to increase recovery efficiency from the Daqing oil field, mobility control and sweep improvement will be especially important and challenging during implementation of any future ASP process.
Polymer flooding is a widely adopted Enhanced Oil Recovery (EOR) technique that enhances oil displacement by addressing sweep efficiency issues and unfavorable mobility ratios between water and oil. Unlike conventional waterflooding, polymer flooding improves sweep efficiency by increasing the viscosity of the injected fluid. This paper addresses what happens when polymer injection is stopped, and water injection is resumed. It investigates whether the integrity of the polymer slug is preserved, the rationale behind current practices, and strategies to mitigate adverse effects. Insights are supported by global field data to guide future project designs.
This review presents our perspective on the factors that have brought polymer flooding to its current
state. Insights are provided on why HPAM is the dominant polymer used as well as what is needed to make alternative polymers and mobility-control methods viable. Explanation is given for why large polymer banks are needed for polymer flooding, and design of the injected polymer viscosity is detailed for cases with/without crossflow. The role of fractures and horizontal wells are discussed for improving injectivity and extending polymer flooding to recover oils with viscosities as high as 10,000 cP. Operational improvements are described to minimize mechanical and oxidative stability to allow HPAM polymers to be viable to 70 C and ATBS polymers to 120 C. Key factors affecting polymer retention are summarized. The paper points out unresolved issues and future directions for polymer flooding.
This paper describes the design procedures that led to favorable incremental oil production and reduced water production during 12 years of successful polymer flooding in the Daqing oil field. Special emphasis is placed on some new design factors that were found to be important on the basis of extensive experience with polymer flooding. These factors include (1) recognizing when profile modification is needed before polymer injection and when zone isolation is of value during polymer injection, (2) establishing the optimum polymer formulations and injection rates, and (3) time-dependent variation of the molecular weight of the polymer used in the injected slugs.
This paper reviews historical and current practices in polymer flooding, analyzing polymer viscosities, concentrations, and slug sizes. It discusses why recent projects tend to use higher viscosities and larger banks than earlier efforts. It also addresses misconceptions about post-polymer waterflooding and the ability of polymers to reduce Sor. The paper concludes with design guidance for injectivity, bank sizing, and economic optimization, especially under low oil prices.
This continuation analyzes how screening criteria can assist in early evaluation of candidate reservoirs and how oil price affects EOR project feasibility. CO2 flooding potential is discussed through depth and gravity data across nearly 1,000 fields. Despite price fluctuations, actual incremental oil from EOR projects aligns with predictions. A hypothetical estimate suggests that 67 billion tons of CO2 could yield 206 billion bbls of oil. The role of economic feasibility and modern reservoir management practices is highlighted.
Screening criteria have been proposed for all enhanced oil recovery (EOR) methods. Data from EOR projects around the world have been examined and the optimum reservoir/oil characteristics for successful projects have been noted. The oil gravity ranges of the oils of current EOR methods have been compiled and the results are presented graphically. The proposed screening criteria are based on both field results and oil recovery mechanisms. The current state of the art for all methods is presented briefly, and relationships between them are described. Steamflooding is still the dominant EOR method. All chemical flooding has been declining, but polymers and gels are being used successfully for sweep improvement and water shutoff. Only CO₂ flooding activity has increased continuously.
This paper evaluates whether polymer’s viscoelastic effects, shown to reduce residual oil saturation (Sor) in lab conditions, are realized in field polymer floods. Two methodologies were used: comparing average field Darcy velocities with shear thickening onset velocities, and reviewing Sor reduction potential based on coreflood experiments. Findings across nine countries indicate that most fields do not reach viscoelastic thresholds, making Sor reduction unlikely. Other mechanisms such as wettability alteration are discussed.