Relative permeability characteristics for surfactant-polymer enhanced oil recovery

A surfactant-polymer chemical flood is considered to enhance oil recovery significantly by the following mechanisms: 1. Reducing oil-water interfacial tension (1FT) 2. Altering wettability characteristics of the reservoir rock 3. Enhancing the viscosity characteristics of the driving fluid. However, the stage of production at which this chemical intervention is made may have a marked influence on the performance of the surfactant-polymer injection as an economical enhanced recovery process.;This study concludes that surfactant-polymer injection for earlier intervention as against its current use as a tertiary recovery method is a viable alternative.;This study experimentally determines and discusses the variations in oil-water relative permeability for a core undergoing surfactant-polymer flooding for enhanced oil recovery. Several core flood experiments with a bench-top relative permeameter were conducted on Fontainebleau sandstone. Cores were subjected to chemical flooding after being prepared to various degrees of water saturation. The different initial water saturations were representative of different stages of a reservoir's production life. A core flood simulator was used to calculate oil-water relative permeability by history matching the volume of oil recovered and the pressure drop measured for selected scenarios. The relative permeability curves are further discussed to ascertain the advantages and disadvantages of the different approaches.