ENHANCING THE SPONTANEOUS IMBIBITION PROCESS IN NATURALLY FRACTURED RESERVOIRS THROUGH WETTABILITY ALTERATION USING: NANOPARTICLES

Naturally fractured reservoirs are characterized by having low-permeability matrix blocks surrounded with fractures of high hydraulic conductivity. Water flooding process insuch reservoirs is successful if the matrix blocks holding the dominant fraction of the reservoir porosity, are able toimbibe the injected water (water-wet) and expel the oil intothe fracture system and finally to the production well. Thismechanism referred to as spontaneous imbibition of waterinto the matrix blocks is an efficient method to increase oil recovery from fractured reservoirs. However, mostnaturally fractured reservoir rocks are mixed- to oil-wetand do not imbibe the injected water, which translates into low-efficiency water flood recovery.To enhance the spontaneous imbibitions process, low concentration of surfactants or lipophobic and hydrophilic polysilicon (LHP), is dissolved into the injected water toinduce wetability alteration of the reservoir rock by changing the wetability of the rock toward a more waterwetstate. This is the main subject of this study. In conclusion, oil recovery can obviously be improved by flooding with hydrophilic nanometer powders by changingthe wetability of the rock toward a more water-wet state asshown by the single block simulation model presented at this study. Since by flooding with hydrophilic nanometer powders permeability decline for the retention of nanoparticles in porous media ,it is suggested that an LHPconcentration ranging from 2.0–3.0% percent by volume is preferable to enhance oil recovery