Study Reviews Recent Polymerflooding Advances in China

Abstract

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 200084, “Recent Advances of Polymerflooding in China,” by Hu Guo and Kaoping Song, China University of Petroleum, and Yuming Wang, Daqing Oilfield Company, et al. The paper has not been peer reviewed. Polymerflooding is one of the more promising chemical enhanced oil recovery (EOR) techniques that features high incremental oil recovery factor, low cost, and wide reservoir applicability. This paper helps clarify ideas regarding polymerflooding implementation based on theory and practice in China. Introduction Laboratory studies aimed at increasing understanding of polymerflooding involve criteria for matching polymer with porous media, the polymer viscoelasticity effect on residual oil saturation (ROS), and displacement efficiency and synthesis of new polymers with better viscosifying capacity compared with typical partially hydrolyzed polyacrylamide (HPAM). The plugging of injectors in many oil fields is becoming increasingly common in many commercial blocks. This problem is especially serious for high-concentration polymer-injection blocks in fields such as Daqing, Xinjiang, and Henan. Understanding this phenomenon involves aligning the polymer and porous-media parameters such as permeability and pore size. Actual reservoir pressure distribution also must be considered. Because modern chemical EOR is based on ultralow interfacial tension (IFT) and minimum mobility ratio theory, the idea of combining the benefits of reducing IFT and increasing displacing-phase viscosity leads to a synthesis of amphiphilic polymers, which have features of both polymers and surfactants. This new type of polymer is sometimes called polymeric surfactant in China.