The Effect of Clay Content in the Adsorption of Surfactant by Reservoir Rock in the Enhanced Oil Recovery Process

Abstract

Surfactant flooding aims at lowering the interfacial tensions between the oil and water phases to improve the displacement efficiency during oil recovery. However, high adsorption of surfactant by reservoir core is undesirable since it could decrease the ability of surfactant to reduce the interfacial tension between oil and brine which makes injection ineffective. This study was done to get better understanding of the effect of clay content on oil displacement. The procedures of adsorption process are as follows: crushed core were put into flasks wich filled with surfactant and heated up at different temperature for three days operation. The clean solution was then measured its absorbance using UV spectrophotometer. The result of adsorption experiments show that the adsorption decreasedup to 25 % when temperature was increased from 25 to 70oC. The experimental for studying the effect of clay content on the adsorption also shows the right behavior. The experimental results also show that adsorption of surfactant is higher in the clean core than in the core filled with oil. This phenomenon is true since the contact area between surfactant and core is much higher when the core is clean. The oil displacement experiments show that the oil recovery also depends on type of reservoir rock used in the process.