Page 79 - Hybrid Enhanced Oil Recovery Using Smart Waterflooding

CHAPTER 4 Hybrid Chemical EOR Using Low-Salinity and Smart Waterflood 71

100 16
LS 300 ppm polymer LPS
90
14
80
12
70 10
Recovery Factor (% OOIP) 50 8 6 4 Differential Pressure (psi) Injection Rate (cc/min)
60

40
30
20
10
0 2 0
0 5 10 15 20 25 30
Volume Injected (PVinj)
Recovery Factor Differential Pressure Injection Rate
FIG. 4.3 The history of oil recovery, differential pressure, and injection rate from the experiment. (Credit: From
Shaker Shiran, B., & Skauge, A. (2013). Enhanced oil recovery (EOR) by combined low salinity water/polymer
flooding. Energy and Fuels, 27(3), 1223e1235. https://doi.org/10.1021/ef301538e.) 0.2

Incremental Recovery Factor (% OOIP) 16 8 6 4 0.16 Residual Oil Saturation (frac. PV)
20
0.18
18
0.14
14
12
0.12
10
0.1
0.08
0.06
0.04
2
0
0
0 1 2 3 4 5 6 0.02
Volume Injected (PVinj)
RF (S12) RF (S6-S7) Sor (S12) Sor (S6-S7)
FIG. 4.4 The history of residual oil saturation and oil recovery from the experiment. (Credit: From Shaker
Shiran, B., & Skauge, A. (2013). Enhanced oil recovery (EOR) by combined low salinity water/polymer
flooding. Energy and Fuels, 27(3), 1223e1235. https://doi.org/10.1021/ef301538e.)

the significant reduction in residual oil saturation to the LSPF using polymer in terms of transport in the
through the combined process of polymer flood and intermediate water-wet Berea and Bentheimer cores.
LSWF (Fig. 4.4). This study experimentally demon- There are a number of gel types such as strong gel
strated the high performance of the combination of (bulk gel), weak gel (colloidal dispersion gel), or linked
LSWF and polymer on the viscous oil recovery. Another polymer solution. In this study, the linked polymer
study (Shiran & Skauge, 2014) made an effort to inves- solution of nanosized particles is used. The linked poly-
tigate the role of the linked polymer on the performance mer solution normally consists of high-molecular-
of LSPF. weight polymer such as HPAM and a cross-linker such
Shiran and Skauge (2014) investigated how the as polyvalent cations. It is reported that the gel forma-
tion reaction is slow and requires time on the order of
hybrid LSPF using linked polymer, i.e., low salinitye
augmented gel treatment, is different from or similar days and weeks. This study prepared the linked polymer