Simulation of Residual oil Saturation in Near-miscible gas Flooding Through Saturation-dependent Tuning of the Equilibrium Constants

Abstract The relationship between residual saturation and wettability is critical for modeling enhanced oil recovery (EOR) processes. The wetting state of a core is often quantified through Amott indices, which are estimated from the ratio of the saturation fraction that flows spontaneously to the total saturation change that occurs due to spontaneous flow and forced injection. Coreflooding experiments have shown that residual oil saturation trends against wettability indices typically show a minimum around mixed-wet conditions. Amott indices, however, provides an average measure of wettability (contact angle), which are intrinsically dependent on a variety of factors such as the initial oil saturation, aging conditions, etc. Thus, the use of Amott indices could potentially cloud the observed trends of residual saturation with wettability. Using pore network modeling (PNM), we show that residual oil saturation varies monotonically with the contact angle, which is a direct measure of wettability. That is, for fixed initial oil saturation, the residual oil saturation decreases monotonically as the reservoir becomes more water-wet (decreasing contact angle). Further, calculation of Amott indices for the PNM data sets show that a plot of the residual oil saturation versus Amott indices also shows this monotonic trend, but only if the initial oil saturation is kept fixed. Thus, for the cases presented here, we show that there is no minimum residual saturation at mixed-wet conditions as wettability changes. This can have important implications for low salinity waterflooding or other EOR processes where wettability is altered.

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New Method of Incorporating Immobile and Non-vaporizing Residual Oil Saturation Into Compositional Reservoir Simulation of Gasflooding

SPE Reservoir Evaluation & Engineering ◽

10.2118/88719-pa ◽

2007 ◽

Vol 10 (01) ◽

pp. 60-65 ◽

Cited By ~ 10

Author(s):

Takeshi Hiraiwa ◽

Koichi Suzuki

Keyword(s):

Reservoir Simulation ◽

New Method ◽

Residual Oil ◽

Oil Saturation ◽

Residual Oil Saturation

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Residual-oil-saturation-technology test, Bell Creek Field, Montana. Final report

10.2172/6385411 ◽

1981 ◽

Author(s):

Keyword(s):

Final Report ◽

Residual Oil ◽

Oil Saturation ◽

Residual Oil Saturation

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SURFACTANT-POLYMER FLOODING PERFORMANCE IN HETEROGENEOUS TWO-LAYERED POROUS MEDIA

IIUM Engineering Journal ◽

10.31436/iiumej.v12i1.37 ◽

2011 ◽

Vol 12 (1) ◽

pp. 31-38 ◽

Cited By ~ 3

Author(s):

Muhammad Taufiq Fathaddin ◽

Asri Nugrahanti ◽

Putri Nurizatulshira Buang ◽

Khaled Abdalla Elraies

Keyword(s):

Porous Media ◽

Oil Recovery ◽

Polymer Flooding ◽

Water Flooding ◽

Residual Oil ◽

Oil Saturation ◽

Reservoir Heterogeneity ◽

Residual Oil Saturation ◽

Layered Porous Media ◽

Multiple Porosity

In this paper, simulation study was conducted to investigate the effect of spatial heterogeneity of multiple porosity fields on oil recovery, residual oil and microemulsion saturation. The generated porosity fields were applied into UTCHEM for simulating surfactant-polymer flooding in heterogeneous two-layered porous media. From the analysis, surfactant-polymer flooding was more sensitive than water flooding to the spatial distribution of multiple porosity fields. Residual oil saturation in upper and lower layers after water and polymer flooding was about the same with the reservoir heterogeneity. On the other hand, residual oil saturation in the two layers after surfactant-polymer flooding became more unequal as surfactant concentration increased. Surfactant-polymer flooding had higher oil recovery than water and polymer flooding within the range studied. The variation of oil recovery due to the reservoir heterogeneity was under 9.2%.

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