Experimental Study of Wettability Alteration of Porous Media by Silica Nanoparticles

Increasing of world demand for energy requires the increase in production of crude oil. Therefore, innovative enhanced oil recovery (EOR) methods have been the subject of many different kinds of studies. The use of nanotechnology has recently gained momentum in the oil and gas industry for its potential applications in EOR processes. Nanoparticles affect the wetting conditions of porous media which is a key factor in displacement efficiency. However, the effect of nanoparticles on wettability of porous media remains still little understood in the available literatures. In this work, the effect of hydrophilic silica nanoparticles on wettability of reservoir rock has been investigated. Contact angle of oil droplets in oil/water/rock system was used as an index of wettability conditions of surfaces. Obtained results revealed that the wettability of oil-wetted rocks in presence of silica nanoparticles changes from oil-wet to water wet; moreover, by increasing temperature and concentration of nanoparticles, the wettability alteration occurred in much less time. Finally, using micromodel setup some flooding tests has been performed in one-quarter five-spot glass micromodel to evaluate the effect of silica nanoparticles on sweep efficiency of water flooding process.