High Salinity and High Temperature Stable Colloidal Silica Nanoparticles with Wettability Alteration Ability for EOR...

Area of Science:

• Materials Science
• Petroleum Engineering
• Nanotechnology

Background:

• Nanoparticle stability in reservoir conditions is critical for enhanced oil recovery (EOR).
• High salinity and temperature pose significant challenges for long-term nanoparticle stabilization.

Purpose of the Study:

• To enhance the stability of silica nanoparticles under harsh reservoir conditions.
• To evaluate the wettability alteration capabilities of modified nanoparticles on reservoir rock surfaces.

Main Methods:

• Surface modification of silica nanoparticles using zwitterionic and hydrophilic silanes.
• Static and accelerated stability analyses in high salinity brines at elevated temperatures.
• Contact angle measurements on sandstone and carbonate rock surfaces.

Main Results:

• Modified nanoparticles demonstrated excellent stability in 3.5% NaCl brine and synthetic seawater at 60 °C for one month.
• Accelerated stability tests predicted nanoparticle stability for at least six months.
• Nanoparticles effectively altered rock wettability to water-wet, with greater impact on carbonate surfaces.

Conclusions:

• Surface modification significantly improves silica nanoparticle stability for oilfield applications.
• The modified nanoparticles show potential for improving oil recovery, particularly in carbonate reservoirs.
• The study provides a pathway for developing stable nanofluids for EOR.