Page 109 - Hybrid Enhanced Oil Recovery Using Smart Waterflooding

CHAPTER 4 Hybrid Chemical EOR Using Low-Salinity and Smart Waterflood 101

(A)
0.4
Equilibrium oil-brine contact angle for 100-200 micron pores:
Swi
HSWF
HSSWF
Average oil-brine contact angle:
0.3 Swi
HSWF
HSSWF
Relative frequency 0.2

0.1

50 60 70 80 90 100 110 120 130 140 150
Contact angle (degrees)
(B)
0.4
Equilibrium oil-brine contact angle for 100-200 micron pores:
Swi
LSWF
LSSWF
Average oil-brine contact angle:
0.3 Swi
LSWF
Relative frequency 0.2
LSSWF

0.1

50 60 70 80 90 100 110 120 130 140 150
Contact angle (degrees)
FIG. 4.31 Distribution of in situ contact angle during coreflooding of (A) conventional waterflood and high-
salinity surfactant flood, and (B) low-salinity waterflood and low-salinity surfactant flood in the pore size on
the order of 100e200 mm. (Credit: From Mirchi, V. (2018). Pore-scale investigation of the effect of surfactant on
fluid occupancies during low-salinity waterflooding in carbonates. Paper presented at the SPE Annual technical
Conference and exhibition, Dallas, Texas, USA, 24e26 September. https://doi.org/10.2118/194045-STU.)