Investigation of Smartwater to Reduce Surfactant Adsorption on Carbonates

Abstract

Summary SmartWater was investigated in reducing surfactant adsorption for carbonate reservoirs under high temperature and high salinity conditions. SmartWater is a 10-fold dilution of the synthetic high salinity water (HSW). SmartWater was compared with the HSW for the effectiveness of reducing surfactant adsorption on carbonate reservoirs under high temperature and high salinity conditions. The adsorption results of surfactants preparing in SmartWater and in HSW showed the SmartWater significantly reduced the surfactant blend adsorption up to 70%; however, no effect on the amphoteric surfactant adsorption. Zeta potential measurements presented that the SmartWater caused less negative of the surface charge in the surfactant blend solution, thus resulting lower adsorption of the anionic surfactant blend on the positively charged carbonate surface. For the amphoteric surfactant, on the other hand, the change of surface charge was negligible in SmartWater comparing to in the HSW. SmartWater did not show any effect on the adsorption of the amphoteric surfactant. Therefore, the effectiveness of SmartWater on adsorption reduction results in possible application with special types of surfactants. This work provides a methodology to identify surfactant adsorption on carbonate rocks and introduces SmartWater to reduce the chemical cost in surfactant injection applications.