Page 86 - Gas Wettability of Reservoir Rock Surfaces with Porous Media

70 Gas Wettability of Reservoir Rock Surfaces with Porous Media

Table 2.12 Relationship Among Gas-wetting Parameters of Glass Slides, Contact Angles of
Liquid, and Surface Free Energy
γ d γ p γ
C Zonyl8740 glassslide glass slide glass slide θ water ( ) ζ gas- θ Oct ( ) ζ gas-Oct
(%) 2 2 2 water
ðmJ=m Þ ðmJ=m Þ ðmJ=m Þ
γ
C Zonyl8740 d γ p γ θ water ( ) ζ 气-水 θ Oct ζ 气-烷

(%) glassslide glassslide glassslide

2 2 2 ( )
ðmJ=m Þ ðmJ=m Þ ðmJ=m Þ
0.01 22.72 7.90 30.615 80.64 2 0.163 35.455 2 0.815
0.1 19.79 3.99 23.778 92.16 0.038 46.08 2 0.694
0.5 18.15 1.64 19.785 101.69 0.203 51.55 2 0.622
1.0 17.48 1.69 19.318 102.02 0.208 53.67 2 0.592
1.5 17.17 1.67 18.845 102.40 0.215 54.72 2 0.578
4.0 16.67 1.52 18.188 103.57 0.235 56.33 2 0.554
8.0 13.62 1.34 14.959 107.43 0.300 66.11 2 0.405
10.0 13.49 1.33 14.820 107.60 0.302 66.54 2 0.398

32
0.3
30
0.2
28 0.1
0.0
26 –0.1
γ glass slide 24 Gas wettability index ζ gas-liquid –0.2
22
–0.3
20 –0.4
18 –0.5
16 –0.6
–0.7
14 –0.8
0 2 4 6 8 10 0 2 4 6 8 10
C zony18740 (wt%) C zony18740 (wt%)
γ Surface energy of glass slide
glass slide
gas wettability index of air on the surface of glass slide with respect to water
ζ gas-water
gas wettability index of air on the surface of glass slide with respect to
ζ gas-n-hexadecane
n-hexadecane
FIGURE 2.31
Relationship among C Zonyl8740 ,γ glass slide , ζ gas-water , and ζ gas-n-hexadecane .

2. Experimental study of the effect of free energy of liquid surfaces and solid/liquid
interface free energy on gas wettability
In the air, the values of gas-wetting parameter of glass slide/water/air
and glass slide/n-hexadecane/air systems, free energy of glass slide sur-
face (γ glass slide ), glass slide/water interface free energy(γ glass slide-water ),