Method for Laboratory and Field Evaluation of a Proposed Polymer Flood

Abstract

Summary The relevant components of a proposed polymer flood in the Tensleep reservoir of the Frannie Phosphoria-Tensleep Unit in Park County, WY, were investigated. Laboratory testing consisted of polymer injectivity, stability, retention, and effective viscosity measurements. On the basis of polymer viscosity and retention tests, a polysaccharide polymer was chosen over a Polyacrylamide polymer for extensive laboratory evaluation and field pilot tests. Field testing included injectivity, biological stability, and in-situ viscosity measurements. Pressure falloff tests following variable-rate injection of a polysaccharide polymer solution indicated the presence of a non-Newtonian, low-mobility bank. Even though good injectivity was obtained during injection of a 15% PV polymer slug, the proposed field project was not done. This was primarily because of low in-situ (reservoir) polymer solution viscosity and lack of proven microbial control in the near-wellbore region.