Page 87 - Gas Wettability of Reservoir Rock Surfaces with Porous Media

Evaluation Methods and Influencing Factors CHAPTER 2 71

Table 2.13 Relationship Among Gas-Wetting Parameter of Glass Slide Surfaces, Contact
Angle of Liquid, and Surface Free Energy

A W A Hex θ water ζ gas-water θ Oct
C Zonyl8740 % γ glass γ glass γ glass ζ gas-Oct

slide-Water slide-Oct slide mJ=m 2 mJ=m 2 ( ) ( )
mJ=m 2 mJ=m 2 mJ=m 2
0.01 18.771 29.800 30.615 11.844 0.815 80.64 2 0.163 35.46 2 0.815
0.1 26.518 23.084 23.778 2 2.74 0.694 92.16 0.038 46.08 2 0.694
0.5 34.535 19.163 19.785 2 14.75 0.622 101.69 0.203 51.55 2 0.622
1.0 34.475 18.726 19.318 2 15.157 0.592 102.02 0.208 53.67 2 0.592
1.5 34.478 18.267 18.845 2 15.633 0.578 102.40 0.215 54.72 2 0.578
4.0 35.269 17.634 18.188 2 17.081 0.554 103.57 0.235 56.33 2 0.554
8.0 36.766 14.554 14.959 2 21.807 0.405 107.43 0.300 66.11 2 0.405
10.0 36.833 14.422 14.82 2 22.013 0.398 107.60 0.302 66.54 2 0.398

Free energy of glass slide/water interface
Free energy of glass slide surface
35
30

25
γ (mJ/m 2 ) 20

15

10
5
0
–0.2 –0.1 0.0 0.1 0.2 0.3
Gas wettability index of air on the surface of glass slide with respect to water ζ gas-water
FIGURE 2.32
Relationship between gas-wetting parameter ζ gas-water and interface free energy.

glass slide/n-hexadecane interface free energy (γ glass slide-inn-hexadecane ),
work of adhesive A W of glass slide/water/air system, and work of adhe-
sive A Hex of glass slide/n-hexadecane/air can be deduced and worked
out by combining Table 2.12 and the theoretical relationship illustrated
in Section 4.2.1. See Table 2.13 for the results.

In glass slide-water-air system, the relationship between gas-wetting parameter
ζ gas-water of air on glass slide surface with respect to water and glass slide/water
interface free energy and free energy of glass slide surface γ glass slide is displayed
in Fig. 2.32. The relationship between ζ gas-water and work of adhesion A W is
displayed in Fig. 2.33.