کلیدواژهها
|
Electrokinetic, Streaming Potential, Zeta Potential, Excess Charge, Silica Nanoparticles, Wettability, Oil-wet Calcite
|
چکیده
|
Application of nanoparticles for wettability
alteration offers a practical approach to resolve some surfacerelated
problems encountered in the nowadays technological
process. Examples are underground/subsurface engineering
implications, including the enhanced oil recovery from the oilwet
carbonate reservoirs. However, the common wettability
evaluating techniques such as contact angle and flotation cannot
be representative of the dynamic phenomena occurring at the
pore scale and hence are unable to give accurate information
about the process. Therefore, in the present work, the
electrokinetic evaluations are utilized to explore the wettability
alteration of initially oil-wet carbonate rock using silica
nanofluids at the porous media conditions. Significant efforts
have been considered to design an in-house experimental setup to provide reliable results pertaining to the electrokinetic
parameters at the different wetting states. Following the treatment of oil-wet calcite sands using silica nanofluids of different
concentrations, the streaming potential coupling coefficient and zeta potential, as well as the excess surface charge, are evaluated.
A mechanistic study (demonstrated by FESEM visualizations) along with some averaging schemes reveals that the change in the
wettability of oil-wet porous media by silica nanoparticles does indeed affect the electrokinetic attributes of the studied system
and thereby can be characterized.
|