Polymer selection workflows for chemical Enhanced Oil Recovery (EOR) face significant challenges due to the complex and variable conditions in reservoirs. One of the core difficulties is ensuring that polymers maintain their viscosifying power under varying conditions, such as reservoir temperature, salinity, and shear forces. A critical factor in this workflow is the steady propagation of polymers without causing plugging or unexpected pressure build-up, which can reduce injectivity.
Additionally, polymer solutions need to demonstrate viscosity stability over time, as losses due to retention, thermal effects, or chemical degradation can reduce effectiveness. However, current polymer selection practices suffer from a lack of standardization, making comparisons between different studies challenging. Various testing methods, such as rheological testing and core flooding, are used to assess polymer performance, but these often do not adequately replicate field conditions. For instance, laboratory tests typically involve higher filtration and pristine water conditions that do not reflect the contamination levels in real reservoirs. This disconnect between laboratory testing and field application introduces risks, such as inaccurate assessments of injectivity and polymer behavior, which can lead to costly failures in the field.
Furthermore, differences in polymer preparation methods, filtration standards, and mechanical degradation during injection are not consistently accounted for in testing protocols, which further complicates the development of a reliable, standardized polymer selection workflow for EOR applications​.
We discuss this topic with Randy Seright in this episode of the Excel Or Routine Podcast which can be found here.
The old (and mostly outdated) API RP63 procedure. But still useful.