Improving the gas condensate recovery through wettability alteration to gas-wet during gas recycling via dispersion of nanoparticles in gas

Abstract

This research investigates the role of dispersion of nanoparticles in gas during gas recycling process to improve the gas condensate recovery via altering the carbonate reservoirs wettability. The nanoparticles were synthesized and analyzed using dynamic light scattering (DLS), energy-dispersive X-ray (EDX), and transmission electron microscopy (TEM). After that, the dispersion of nanoparticles in methane was investigated by cloud point pressures measurement. Also, the effectiveness of methane/nanoparticles solutions was assessed through the contact angle experiments and gas recycling process. Based on the cloud point pressures results, the nanoparticles can be dispersed in methane at pressures commensurate with hydrocarbon reservoirs. Gas/nanoparticles single-phase solutions increased the contact angles of gas condensate and n-decane from 12° to 121° and 135.5°, respectively, for fluorinated silica, and to 100.5° and 108° for fluorinated titania. The shift from oil-wet to gas-wet conditions enhanced the recovery factor from 55% to 76%, marking a 21% improvement in gas condensate recovery during gas recycling. Furthermore, the pressure drop ratio decreased by 60%, due to better surface wettability and reduced condensate blockage. Comparative results indicated that the dispersion of fluorinated silica nanoparticles in gas outperformed fluorinated titania in altering wettability. These results emphasize the potential of current new approach, through dispersion of fluorinated nanoparticles in gas; to improve gas condensate recovery during gas recycling, especially in low-permeability carbonate reservoirs.