The Influence of Nano Fluid Compared With Polyethylene Glycol and Surfactant on Wettability Alteration of Carbonate Rock

Abstract

The purpose of this research is to enhance oil recovery of the carbonate rock by wettability alteration using silica suspended in brine, polyethylene glycol (PEG), and sodium dodecyl sulfate (SDS). Hydrophilic silica with a different mean Nano size 52, 65 nm was synthesized from local sand by a chemical method. The synthesized Nano silica was characterized by AFM to determine the average particle size and distribution, and surface area was measured by physical adsorption of nitrogen. The wettability alteration was studied by dipping the carbonate rock in different concentrations of Nano silica (0.01-1wt. %) for a certain silica size suspended in brine for different dipping times as well as for PEG and SDS. The contact angle was measured before and after each run in order to recognize the extent of affinity change (wettability) of the carbonate. The results showed that the Nano particles were more reactive due to their high surface area these particles had the highest potential for wettability alteration. The contact angle decreased with decrease particle size and increase concentration. The PEG polymer and SDS surfactant showed less influence on wettability alteration compared with Nano fluids.