Published: Nov. 4, 2024

Abstract High-resolution three-dimensional micro-CT imaging is used to investigate nitrogen, carbon dioxide, and hydrogen injection in reservoir carbonate rocks. The images were analysed ascertain gas saturation, pore occupancy, ganglia size connectivity across the sample. experiment studies a water-wet rock that filled with synthetic brine before between each injection. experimental conditions involve unsteady-state at pressure of 9 MPa, temperature 60°C, rate 0.005 mL/min, 0.1 mL/min remove all sample firstly saturated brine, followed by N2 injection, then Images are taken throughout phase after waiting 24 hours This procedure replicated for CO2 H2 cycles. saturation gases as follows: around 25%, approximately 21%, 18%. While slightly decreased hours, remained relatively stable over time. profile reveals experience more significant changes during period caused Ostwald ripening compared propagate centre Capillary measurements based on interfacial curvature 80% indicate decline N2, from 1.46 kPa 1.18 hours. experiences decrease 1.17 1.05 while shows minimal capillary time remaining 1.04 kPa. Pore occupancy analysis occupying pores mostly above 25 µm radius, increase larger Throat radii than 18 show an indicating improved connectivity, supported normalized Euler number. predominantly occupies 30 40 change. 19 throats 8 increased suggests enhanced connectivity. Overall, this study provides useful reference comparing displacement trapping behaviour waterflooding which have been studied extensively, those H2, applicable storage projects within reservoirs.

Language: Английский