The Impact of Temperature on the Effectiveness of Surfactant to Change the Wettability

Utilization of surfactants is one of the methods for wettability alteration of reservoir
rock, from oil wet into water wet by reducing the interfacial tension. Studying of
wettability alteration mechanism using surfactants has been emphasized by researches.
Later on, many researchers have focused on surfactants capability of tolerating on a
condition created by increasing temperature to increase their ultimate recovenes.
However the wettability of porous media is difficult to observe directly during the
injection of the surfactant process. Many differ in opinion among researchers for the
exact temperature on the effectiveness of surfactant and contact angle to recover the oil.
Therefore, experimental study needs to be perfonned to observe the changes in contact
angle at the optimum temperature.The objective of this experimental study is to
investigate the impact of different temperatures, rangmg from so'C-120'c on the
surfactant's performance in altering the wettability of a rock. In this study, sessile up
method for contact angle measurement have been made using Berea sandstone core
sample, Dulang crude oil in the presence of Sodium Dodecyl Sulfate (SDS) surfactant at
pressure 200 psia and constant salinity of 5000ppm. The experiment is being conducted
using the Interfacial Tension 700 (IFT700) tool and measured the contact angle. The
changes in contact angle when temperatures are increasing have been evaluated. The
contact angle is found to decrease from 110' to 48' as the temperature increase. The
wettability has been enhanced and changed from oil wet to water wet means contact
angle decreasing as temperature increases, leading to increase the oil recovery.