Page 298 - Enhanced Oil Recovery in Shale and Tight Reservoirs

EOR mechanisms of wettability alteration and its comparison with IFT 271

(A) 0.35 MK in Kerosene (B) 0.35 OP in Kerosene
0.4
0.4
Imbibed Volume/Pore Volume 0.25 MK in 2wt.%KCI Excess Imbibed Volume/Pore Volume 0.25 Excess
OP in 2wt.%KCI
0.3
0.3
0.2
0.2
Aftinity
to Water
0.15
0.15
Aftinity
0.1
0.1
to Water
0.05
0
1000 10000 100000 1000000 10000000 0.05 0 10000 100000 1000000 10000000
1000
Dimensionless Time (t D ) Dimensionless Time (t D )
(C) 0.35 EV in kerosene
0.4
Imbibed Volume/Pore Volume 0.25 EV in 2 wt.% KCI Excess
0.3

0.2
Aftinity
to Water
0.15
0.1
0.05

1000 0 10000 100000 1000000 10000000

Dimensionless Time (t D )
Figure 9.37 Normalized imbibed oil and brine volumes versus dimensionless time for
intact Horn River samples (Lan et al., 2015b).

of oil-water-flat surface system (liquid-liquid contact angle); (3) Sponta-
neous imbibition of a liquid into a dry rock sample (initially air saturated),
and (4) water imbibition into an oil-saturated rock sample (an Amott-type
imbibition system). They found that the air-oil contact angles were smaller
(e.g., as shown in Fig. 9.38A). According to Conclusion 2, such wetting
angle cannot determine oil-wetness. They also observed that the oil volume
by spontaneous imbibition into the dry rock sample (Fig. 9.39) was higher.
According to Conclusion 3, it should be oil-wet. Without using Conclu-
sions 2 and 3, one may think the oil-wetness can be determined, as Yassin