Asphaltene Stability and Wettability Alteration During Smart Water Flooding

Invasion of external fluids into the reservoir during different operations could cause formation damage in the form of asphaltene deposition, which consequently, reduces the oil recovery of the recoverable reserve. removing and preventing the asphaltene deposition is a very challenging task. the objective of the present study is to experimentally investigate the wettability alteration during surfactant-smart water flooding and its potential to mitigate asphaltene deposition damage in original oil-wet reservoirs. in this regard, contact angle experiments on carbonate surface treated with different solutions showed contact angles lower than 90°. thus, wettability alteration from oil wetting to more favorable water wet states was achieved. the highest wettability alteration index of 0.9 was obtained when surfactant in a brine solution containing 9.61 g/l sulfate ion has been used, which revealed that large amounts of carboxylate acid adsorbed on the carbonate surface, were removed. the modified surface reduced the hydrophobicity of the surface and promoted the oil production from the reservoir.