Investigating the Effects of Temperature, Pressure, and Paraffin Groups on the N₂ Miscibility in Hydrocarbon Liquids using the Interfacial Tension Measurement Method

In this study, interfacial tension measurement (IFT) is utilized to assess the impact of temperature, pressure, and paraffin type on a nitrogen injection process as an efficient enhanced oil recovery method. The pure and equilibrium densities of oil in contact with nitrogen are examined to find IFT behavior and gas solubility in oil. The minimum miscible pressure (MMP) of different systems has been measured using the vanishing interfacial tension technique. The experimental results show that IFT decreases linearly with pressure, with two different slopes. The results indicate that IFT values decrease linearly with temperature at different pressure conditions. The obtained IFT values for (hexadecane + N₂) and (diesel fuel + N₂) systems are close to each other. The variation in IFT of nitrogen–paraffin systems by pressure shows a similar slope to that of the N₂ and oil mixture (diesel fuel) system. The MMP of different systems was observed to decrease with increasing temperature. The results of this work show that nitrogen injection would be an effective enhanced oil recovery process in high-pressure and high-temperature oil reservoirs