Document Type : Research Paper
Petroleum and Chemical Engineering Department, Ilam University, Ilam, Iran
Recently nanoparticles are used for improving the volume of oil and gas production and Enhanced Oil Recovery (EOR) purposes. Based on our recent researches, using nanoparticles such as Silica and Calcium oxide has a good potential for changing mechanisms in the porous media such as interfacial tension and wettability. For finding the application of nanoparticles in the porous media, low permeability carbonate plugs were selected, and two main steps were used , including 1) Using CaO and SiO2 nanoparticles for wettability alteration, interfacial tension reduction, and improving fluid flow through porous media 2) Surveying the application of nanoparticles on the water alternative gas (NCs assisted WAG) test. The Zeta potential amounts are stable at condition of -56.4±2 mV and -44.0±3 mV for Calcium oxide and Silica nanoparticles, respectively at optimum nanoparticles concentration of 15 ppm. Calcium oxide and Silica nanoparticles have effectively altered the wettability from oil-wet to water-wet by surveying the intersection of two-phase relative permeability. Moreover, CaO nanoparticles had better performance in low permeability carbonate porous media than SiO2 nanoparticles with regards to wettability alteration to water wet. Based on the results and better version of CaO, it was selected for performing NCs assisted WAG tests at WAG ratios of 1:1, 40 ℃, and 15 ppm.The recovery factor was increased from 42.9 % to 73 % in the presence of CaO during performing NCs assisted WAG tests, and residual oil saturation was decreased from 40.9 % to 19.4 %.