Essentials of Polymer Flooding Technique

Chapter five Polymer Flooding–Pilot Design

In this chapter, general guidelines for designing a polymer injection pilot will be provided. Best practices will also be discussed to make the most out of any injection trial.

5.1. Reservoir Screening – Reminder

Given the current recovery factors (averaging 35% oil originally in place (OOIP) after waterflood), there is a high potential for enhanced oil recovery (EOR) in brownfields, using existing infrastructure to facilitate the implementation. General guidelines were provided in Chapter 4 to assess the feasibility of polymer injection in a field. The two principal screening rules for polymer flooding are:

• Pointing out reservoirs that have poor sweep efficiency due to high oil viscosity and/or large‐scale heterogeneity.
• Determining whether the overall conditions are suitable (i.e. compatible brine, mobile oil saturation, retention) for polymer flooding implementation to fix the problem.

Polymer flooding has been applied in both sandstone and carbonate reservoirs. Because injection in carbonates requires a good reservoir understanding and thorough laboratory studies to find the most efficient chemistry, only sandstone reservoirs will be considered here; however, the main screening parameters apply to carbonates as well.

We can narrow the primary parameters needed to check whether polymer flooding is a viable option, by ...