Page 218 - Formation Damage during Improved Oil Recovery Fundamentals and Applications

192 Bin Yuan and Rouzbeh G. Moghanloo

of pressure drop caused by permeability damage as shown in Fig. 4.7.
Because of the precoated nanoparticles onto rock grains prior to the inva-
sion of fines, the impairment of Berea sandstone core permeability can be
completely remedied from the damage case without the further injection
of nanoparticles.
ð 1 ULμ 1 1 β σ FP 1 β S FP Þ
ð
Δpt D 5 a s dx D (4.10)
ðÞ
0 k 0

4.5 USING NANOPARTICLES TO CONTROL FINES
SUSPENSION IN OIL AND WATER-SATURATED POROUS
SYSTEMS

Fines migration in two-phase-fluid (oil and water) flow occurs in
many types of processes in the petroleum industry. As the injection of
low-quality water with solids and liquid particles (produced water or
waste water) continues for the purpose of waterflooding, both the newly
invaded fine particles and the induced formation fines by injected fluids
result in significant formation damage and impair well performance, i.e.,
well injectivity and oil recovery. Plan and design of those projects related
to fines migration in two-phase flow and evaluation of various mechan-
isms by which nanoparticles control fines migration need reliable
physical-based mathematical models.

4.5.1 Nanofluid coinjection to reduce fines
migration in two mobile fluids
It is desirable to introduce nanoparticles as an additive continuously into
the injection fluid stream to control injected fines suspension during vari-
ous types of waterflooding. The coinjected nanoparticles are preferentially
adsorbed onto the surfaces of mobile fines, which help fines more prone
to be attached to become attached to the pore surfaces. As discussed by
Yuan, 2017a; Yuan and Moghanloo, 2018c, the mass-balance equation of
flowing nanoparticles considering their adsorption on mobile fines, and
the mass-balance equation of flowing fines considering their attachment