Influence of Surfactant Type, Surfactant Concentration, and Salinity on Interfacial Tension of a Brine/Live Oil/Surfactant Fluid System: A Case Study of Iranian Asmari Oil Reservoir

The chemical surfactant flooding can mobilize the trapped oil by lowering the interfacial tensionbetween oil and brine and in some cases altering the reservoir rock wettability. In this work, the effectof surfactants on oil/brine interfacial tension was experimentally investigated. First, the effect ofsurfactants concentration was surveyed. Afterwards, the effect of salinity on surfactant behavior wasstudied. The experiments were carried out at ambient and reservoir temperatures (all at reservoirpressure) to clarify that we cannot generalize the ambient experimental results to reservoir ones andthe experiments must be done in reservoir conditions to attain more certainty. Sodium dodecylsulfonate, cetyl trimethyl ammonium bromide and Triton X-100 were used as the surfactants. The oiland brine samples of the Iranian Asmari reservoir were used. Pendant drop method was used tomeasure oil/brine interfacial tension. Based on the results, it is concluded that the anionic surfactant(SDS) has a better performance at reservoir and ambient temperatures. The superiority of SDS is moreemphatic at reservoir temperature than ambient temperature. At reservoir temperature, the SDSsolution lowers the interfacial tension significantly (0.4 mN/m) even when a very low concentrationof SDS (0.04 wt.%) is added to brine.

Influence of Surfactant Type, Surfactant Concentration, and Salinity on Interfacial Tension of a Brine/Live Oil/Surfactant Fluid System: A Case Study of Iranian Asmari Oil Reservoir Keywords:

Surfactant , CTAB , SDS , Optimum Salinity , IFT