Page 211 - Formation Damage during Improved Oil Recovery Fundamentals and Applications

Using Nanofluids to Control Fines Migration in Porous Systems 185

Figure 4.3 Mutual interactions among nanoparticles, fines, and rock grains indicating
various physical mechanisms by which nanoparticles control fines migration.
(A). Scenario I: Co-injection of nanoparticles with fines suspension (B). Scenario II:
Nanoparticle treated pores prior to fines injection (revised after Yuan et al., 2018b).

However, the adsorption capacity of nanoparticles onto fines is not infinite,
which means beyond the maximum limit of nanoparticle adsorption (as a
function of salinity, pH, temperature, and et al.) onto fine particles, the surface
potential of fine particles does not change further. At that moment, the
surface potential of fines can be assumed to become very close to
that of adsorbed nanoparticles. As a result, the maximum retention concentra-
tion of fine particles onto rock grains also reaches the ultimate maximum
attachment concentration value, which is determined by the
surface charges of both nanoparticles and rock grains as shown in Eq. (4.6c)
(Yuan et al., 2016, 2018b).