Nano Spherical Polymer Pilot in a Mature 18° API Sandstone Reservoir Water Flood in Alberta, Canada

Abstract

Abstract A previous SPE paper1 described the operational challenges associated with hydration and viscosity control of linear long-chained hydrolyzed Polyacrylamide (HPAM) using produced formation water from the Lower Mannville (Sparky) formation. Production results were disappointing, but the Pilot Project was considered technically successful. Reservoir heterogeneity in tight laminated sandstone reservoirs impacts the efficiency of water flooding and complicates the application of chemical Enhanced Oil Recovery (EOR) methods for conformance control. In the case of the Wain B Pilot Project, the use of HPAM for mobility and conformance modification in the tight saline Mannville reservoir was considered risky. However, at the time there were no apparent viable chemical flood alternatives. The Operator decided to proceed with a relatively large pilot project, as introduced in the aforementioned SPE 154050 Paper1. The rate of production uplift achieved was considered economically unsuccessful in the time frame expected for capital projects. Polymer injection was ramped down in late 2012, before the designed pore volume displacement had been achieved, and the injection wells were returned to water injection. Since then, an uplift in oil production has been realized. Nevertheless, a different type of chemically assisted EOR technology was required for the range of tight reservoirs under consideration. This current SPE paper will compare production results of that previous Wain B Polymer Pilot Project, which used HPAM 3630s, with early results from a nano spherical polymer (nanosphere) pilot project in the adjacent and similar Scovil Pool in East-Central Alberta, Canada.