A comprehensive review of alkaline-surfactant-polymer (ASP) flooding

Alkaline-surfactant-polymer (ASP) flooding is a combination process in which alkali, surfactant, and polymer are injected in the same slug. Because of the synergy of these three components, ASP is the current worldwide focus of research and field trial in chemical enhanced oil recovery (EOR). This paper is to provide a comprehensive review of the ASP process. The reviewed topics include the following: ASP synergy and its EOR mechanisms Screening criteria Laboratory work Numerical simulation work Summary of pilots and large-scale applications Project economics Chemicals used Water quality Mobility control requirement Problems associated with ASP flooding and possible solutions In addition to the comprehensive review, future developments are also discussed. Data and analyzed results presented in this review will provide the reader with the updated information about ASP and a guide to read relevant papers for those who are new to chemical EOR. The survey data also provide operators with some reference data for their project design and optimization.