Activities on Low Salinity Water Flooding

Abstract

Low Salinity Water Flooding (LSWF) is one of the attractive EOR technologies due to a low cost and environment friendly method. Because the operational configuration in LSWF is similar to that in conventional water flooding and no chemical components that are not present in reservoirs are added to injection water. LSWF has been focused on since 1990's and researchers have proposed some potential mechanisms of how low salinity water works for improving oil recovery. However, the mechanisms have not been sufficiently elucidated.

Recently JOGMEC started a joint study to understand effects of LSWF on oil recovery through laboratory experiment, simulation work and field applications with Waseda University, Kyoto University and PetroVietnam / Vietnam Petroleum Institute. In the laboratory experiment, the effects of LSWF on oil recovery were observed using Berea sandstone cores containing about 1.5% of kaolinite that is considered to be one of the key factors. The mechanism to improve oil recovery suggested the multi component ion exchange. In the simulation work, we are developing in-house simulator to predict not only oil recovery but also ion and pH changes that are typically observed during LSWF based on the mechanism of multi component ion exchange. In addition, we are exploring an opportunity to apply LSWF to oil fields through a comprehensive study involving laboratory, simulation, field pilot and economic evaluation.