Page 245 - Enhanced Oil Recovery in Shale and Tight Reservoirs

228 Enhanced Oil Recovery in Shale and Tight Reservoirs

Figure 9.6 Simulation grids and the initial surfactant concentration.
Table 9.1 Relative permeability and capillary pressure parameters in the base
model.
Initial oil wettability (OW) Altered water wettability (WW)
Oil Water Oil Water
0.38 0.32 0.38 0.32
S or
0.59 0.23 0.59 0.23
End point k r
k r exponent 3.3 2.9 2 2
. 0.5
C pc , psi Darcy 5 5
Contact angle 180 0
2 2
E pc
is the intermediately wet case with u set 0.5. These u values are presented in
Table 9.2. The IFT in these cases is the same, 0.0088 mN/m. From this
figure, we can see that the oil recovery factors are: WW þ IFT case -
> IW þ IFT case > OW þ IFT case, indicating that wettability
alteration improves oil recovery.