Page 94 - Gas Wettability of Reservoir Rock Surfaces with Porous Media

78 Gas Wettability of Reservoir Rock Surfaces with Porous Media

Table 2.15 Experiment Plan on the Effects of Roughness on Gas Wettability
Measuring System Zonyl8740 Concentration (%) HF Treatment Duration (s)
0 20 40
Gas/water 0 W 0 0 W 0 20 W 0 40
0.01 W 0.01 0 W 0.01 20 W 0.01 40
0.5 W 0.5 0 W 0.5 20 W 0.5 40
Gas/oil 0 O 0 0 O 0 20 O 0 40
0.01 O 0.01 0 O 0.01 20 O 0.01 40
0.5 O 0.5 0 O 0.5 20 O 0.5 40
A a b refers to glass slide number. Each glass slide number is prepared as two pieces, which are used for evaluating gas wettability by
sessile drop method and bubble capture method, respectively. When A 5 W, it represents water phase, when A 5 O, it represents oil
phase; a refers to mass concentration of gas-wetting reversal agent, and the values are 0,0.01 and 0.5; b refers to treatment duration
with HF, with values of 0, 20, and 40.

Table 2.16 Effect of Roughness on Gas Wettability (Sessile Drop Method)
Gas/Water System Gas/Oil System
Glass Contact Angle Parameter of Gas Glass Contact Parameter of Gas
Slide of Water Wettability Slide Angle of Oil Wettability ζ gas-oil
Number θ water ( ) ζ gas-water Number θ oil ( )

W 0 0 63.9 2 0.440 O 0 0 13.7 2 0.972
W 0 20 45.8 2 0.697 O 0 20 9.8 2 0.985
W 0 40 32.2 2 0.846 O 0 40 4.7 2 0.997
80.6 2 0.163 35.5 2 0.815
W 0.01 0 O 0.01 0
62.0 2 0.469 28.6 2 0.878
W 0.01 20 O 0.01 20
54.5 2 0.581 17.9 2 0.952
W 0.01 40 O 0.01 40
101.7 0.203 51.6 2 0.622
W 0.5 0 O 0.5 0
109.5 0.334 38.5 2 0.782
W 0.5 20 O 0.5 20
111.4 0.365 22.3 2 0.925
W 0.5 40 O 0.5 40
c. Based on the experiment plan (see Table 2.15), gas wettability is
reversed on glass slides with different roughness.
d. Sessile drop method and bubble capture method are used to evalu-
ate gas wettability of glass slides with different roughness and gas
wettability.

2.4.4.1 STUDY OF SESSILE DROP METHOD

The evaluation of gas wettability of glass slides with different roughness and
gas-wetting in the air is done using sessile drop method. See Table 2.16 for
results.

From Table 2.16, it can be seen that for the glass slide surface treated with
Zonyl8740 solution of the same concentration, when the glass slide has