Pore-scale processes in tertiary low salinity waterflooding in a carbonate rock: Micro-dispersions, water film growth, and wettability change

Selem, Ahmed M.; Agenet, Nicolas; Blunt, Martin J.; Bijeljic, Branko

doi:10.1016/j.jcis.2022.06.063

Cited by 9 publications

(12 citation statements)

References 77 publications

(110 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In secondary mode, the displacement process was more efficient, and oil recovery was quicker. This agrees with the results from previous experimental work on both secondary and tertiary modes where the displacement processes and recovery were more prominent in the secondary mode. , Overall, the work demonstrates the importance of emulsification as a mechanism for improved recovery in LSW. , …”

Section: Discussionsupporting

confidence: 91%

“…The same number of pore volumes injected results in a better displacement with LS compared to HS. This could also be explained by the reduced mobility of the emulsified oil compared to the nonemulsified oil due to differences in viscosity …”

Section: Results and Discussionmentioning

confidence: 99%

“…The asphaltene content of the crude, the salinity gradient between FB, already in the system prior to waterflooding, and injected HSB, and an even higher gradient between FB and LSB in the secondary experiment are elements that induced the emulsification of oil and formation of water microdroplets within the oil and at the oil−brine interfaces. 69 In situ emulsification, at the pore level, during waterflooding depends on the ionic composition of injected brine as well as on pore geometries and rock wettability. 60 In the tertiary experiment, where there was a gradual decrease in salinity from FB to HSB to LSB, the aforementioned mechanisms were observed, albeit in a slower fashion, 21,24,32 whereas in the secondary mode, the mechanisms and processes were more conspicuous.…”

Section: Emulsion As a Low Salinitymentioning

confidence: 99%

“…The field of X-ray microcomputed tomography (micro-CT) has developed remarkably over the past 10 years, and pore-scale characterization studies with high resolution have become possible. , This technique has been utilized in multiple research and industrial applications, e.g., EOR and gas storage. ,,− The merger between high-pressure and high-temperature flow apparatus and X-ray imaging has resulted in large improvements in our understanding of multiphase flow in natural systems at the pore scale. − …”

Section: Introductionmentioning

confidence: 99%

“…Selem et al , conducted pore-scale studies investigating the low salinity effect and recovery in Estaillades carbonate, which is a quarry limestone. Both secondary injection (low salinity brine was injected into a rock sample containing oil and a low initial water saturation) and tertiary injection mode (low salinity brine injection after a period of waterflooding where high salinity brine was injected) were studied.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Pore-Scale Imaging of Emulsification of Oil during Tertiary and Secondary Low Salinity Waterflooding in a Reservoir Carbonate

Selem,

Agenet,

Foroughi

et al. 2023

Energy Fuels

Self Cite

View full text Add to dashboard Cite

While it is known that changing the salinity of the brine used to displace oil in porous rock can lead to additional recovery, the mechanism by which this occurs at the pore scale is still not fully understood. We investigate whether the emulsification of oil is the process by which recovery is improved, removing oil from the solid surface and rendering the rock more water-wet. High-resolution three-dimensional X-ray imaging was used to visualize the emulsification kinetics during secondary and tertiary low salinity waterflooding in a carbonate reservoir rock. The rock samples were imaged during water flooding, where the salinity of the injected brine was much lower than that of the formation water. An intermediate phase that appeared to be a mixture of oil and brine, and which we hypothesize is an emulsion, was imaged in both tertiary and secondary low salinity waterflooding experiments. The formation of this intermediate phase is observed to be the preliminary step prior to oil mobilization. Gray-level histograms and pore occupancy maps showed a faster displacement of oil in the secondary mode compared to tertiary flooding where the emulsified oil remained in the sample for longer before displacement.

show abstract