Laboratory Experiment on Enhanced Oil Recovery Using Nanoparticles (NPs) and Permeability Alteration Due to Their Retention in Porous Media

After secondary flooding, the process of injecting chemicals such as Nanoparticles into the reservoir in order to release and produce the trapped oil in that reservoir is called chemical flooding enhanced oil recovery (CEOR). The trapped oil is due to some forces such as viscous, gravity and capillary forces. Several reservoir problems have been solved with the use of Nanoparticles but the disadvantage is the retention of these Nanoparticles in the pore spaces which can cause pore blockage of reservoir rock and reduce its permeability. The primary aim of oil industry is to find the effect of these nanoparticles on oil recovery. In this work, some types of nanoparticles were selected for sand-pack oil displacement flood test. These Nanoparticles are Magnesium oxide (MgO), Aluminum oxide (Al2O3) and silicon oxide (SiO2). They were selected because of their effect to improve oil recovery. They were used to conduct enhanced oil recovery and to evaluate the effect of their retention in porous media at 45°C and 3000 – 3500 Pisa. The Nanoparticles were dispersed in brine. The control experiment and the experiment when Nanoparticles were dispersed in brine were the two set of experiment conducted. The control experiment was used as a bench mark to compare the effect of nanoparticles on oil recovery. From the results obtained from this experiment, Aluminum oxide (Al2O3) was the best performed Nanoparticle after enhanced oil recovery flooding process. Nanoparticles were used to prepare the nanofluids used for tertiary recovery. Nanofluids used to displace oil yield better results but when only brine was used, the recovery was low compared with that of nanoparticles. Increase in nanoparticle concentration increases oil recovery. There was a decrease in permeability of the reservoir rock. Increase in nanoparticles concentration increases the total cost of preparing the nanofluid. The decrease in permeability is caused by pore blockage due to nanoparticles retention in porous media. Only Al2O3 at 0.2%wt is economical feasible compared with other nanoparticles. The ability of nanoparticles to alter certain factors in the formation and in oil properties can be taken as advantage on oil recovery.