Page 251 - Enhanced Oil Recovery in Shale and Tight Reservoirs

EOR mechanisms of wettability alteration and its comparison with IFT 233

45
40
%
, IFT=0.049 mN/m
n
o 35
i
t
a
r
e
t 30
l
a
t
e
w 25
m
o
r 20
f
F
R
l
a 15
t IFT=0.0323 mN/m
n
e
m 10
e
r
c
n
I IFT=0.0088 mN/m
5
0
0 20 40 60 80 100 120 140
Time, day
Figure 9.10 Effect of wettability alteration on oil recovery by spontaneous imbibition
at different IFT values.
50
45
IFT=0.0088 mN/m
40
%
,
n 35
o
i
t IFT=0.0323 mN/m
a
r 30
e
t l
a
t 25
e
w
t
u 20
o
h
t
i
w 15
F
R
10
5
IFT=0.049 mN/m
0
0 20 40 60 80 100 120 140
Time, day
Figure 9.11 Effect of IFT without wettability alteration.
recovery but mitigate wettability alteration mechanism. The resultant effect
will be the balance of the two negative and positive effects.
Xie et al. (2005) compared the spontaneous imbibition rates using
nonionic poly-oxyethylene alcohol (POA) and cationics (CAC). The IFT
of POA solution was 19 times higher than of CAC solution (5.7 vs.