Abstract
A fundamental chemical enhanced oil recovery (EOR) process is surfactant flooding in which the key mechanism is to reduce interfacial tension between oil and the displacing fluid and hence mobilizing the trapped oil. Surfactant loss by adsorption is one of the most important criteria that governs the economics of the surfactant flooding methods. In addition to this, detrimental effects and high price of currently used surfactants cause EOR process so expensive and unfeasible. This study is aimed to introduce a novel kind of plant based surfactant which is extracted from Zizyphus Spina-Christi tree. In addition, equilibrium adsorption behavior of this novel biosurfactant in aqueous solution on crushed reservoir rocks is presented. A conductivity technique was used to assess the critical micelle concentration (CMC) value in the aqueous phase. Batch experiments were used to understand the effect of adsorbent dose on sorption efficiency as well. Four adsorption models were also employed to make a quantitative description of equilibrium adsorption behavior of surfactant solution. For evaluating the ability of this novel biosurfactant on the surface properties, IFT values of Saponin solution were compared to those of commonly used chemical surfactants in petroleum industry. It is shown that availability and the low cost of the Zizyphus Spina-Christi extract in comparison to common chemical surfactants in petroleum industry make it economically viable for surfactant flooding.
