Page 114 - Hybrid Enhanced Oil Recovery Using Smart Waterflooding

106 Hybrid Enhanced Oil Recovery using Smart Waterflooding

type Ⅰ of microemulsion system. In the coreflooding us- pH, and effluent concentrations are accurately repro-
ing sandstone core, the performance of the various ASP duced through simulations of underoptimum salinitye
formulations is investigated in terms of aqueous solubi- augmented ASP process.
lity of microemulsion, oil recovery, and retention of Dang, Nghiem, Nguyen, et al. (2018) also simulated
surfactant and polymer. The experiments observed the ASP process and evaluated the hypothetical applica-
that the underoptimum salinity condition brings ad- tion of low salinityeaugmented ASP process. The main
vantages to the ASP process. The aqueous solubility of difference between this study and work of Hosseini-
microemulsion is secured without the cosurfactant Nasab et al. (2016) is the modeling of LSWF mecha-
addition. Higher solubility produces the clean oil nism. The previous study of Hosseini-Nasab et al.
bank recovery as well as reducing cost of oil treatment (2016) ignored the mechanism of LSWF because the
at production facilities. In addition, the underoptimum suboptimum condition of 1.5 wt% is much higher
salinity results in less retention of chemical additives than the optimal condition, which is known as less
and can avoid the risk to undergo the overoptimum than 5000 ppm for sandstone, to introduce the mecha-
salinity condition. Hosseini-Nasab et al. (2016) devel- nism of LSWF. Instead, the study mainly focused on
oped the mechanistic model of ASP process under sub- the wettability modification following the mechanisms
optimum salinity conditions based on the experimental of alkaline/surfactant flood. Dang, Nghiem, Nguyen,
results of Battistutta et al. (2015). The mechanistic et al. (2018) developed the mechanistic model of ASP
simulation of ASP process numerically models the poly- process and applied the mechanism of LSWF, wettability
mer rheology, phase behavior of microemulsion, modification, to simulate the low salinityeaugmented
adsorption of chemicals, wettability modification, and ASP process. The mechanistic model of ASP process
reduction of residual oil saturation considering the covers the polymer rheology, phase behavior of microe-
mechanisms of ASP process, and mechanical and chem- mulsion, adsorption of chemicals, relative permeability
ical interactions in crude oil/brine/rock systems. The modification by the wettability modification, and reduc-
historical results of oil production, differential pressure, tion of residual oil saturation. For the modeling of

100

High Salinity Waterflooding
High Salinity Waterflooding + ASP Flooding
80 Low Salinity Waterflooding
Low Salinity Waterflooding + ASP Flooding
Oil Recovery Factor (%) 60

40

20

0
2020 2025 2030 2035 2040
Time (Date)
FIG. 4.36 The oil recovery of low salinityeaugmented ASP flood compared with the low salinity waterflood
and conventional ASP flood. (Credit: From Dang, C., Nghiem, L., Nguyen, N., Yang, C., Chen, Z., & Bae, W.
(2018b). Modeling and optimization of alkaline-surfactant-polymer flooding and hybrid enhanced oil recovery
processes. Journal of Petroleum Science and Engineering, 169, 578e601. https://doi.org/10.1016/j.petrol.
2018.06.017.)