TY - GEN
T1 - Effect of Initial Wettability on Capillary Desaturation by Hybrid Engineered Water/Polymer Flooding in Carbonate Reservoirs
AU - Shakeel, Mariam
AU - Pourafshary, Peyman
AU - Hashmet, Muhammad Rehan
N1 - Publisher Copyright:
© 2022, Avestia Publishing. All rights reserved.
PY - 2022
Y1 - 2022
N2 - Residual oil saturation (Sor) after waterflooding is high in carbonate reservoirs, due to the wettability state, making them a lucrative candidate for novel enhanced oil recovery (EOR) methods such as engineered water/polymer flooding (EWPF). Initial wettability for such reservoirs must be considered during the preliminary screening for an effective EWPF application. This experi mental study investigates the carbonate initial wettability criteria to achieve a successful EWPF design. Contact angles are measured at 80oC to evaluate the temperature effect on wettability shift by engineered water (EW). Coreflood tests are conducted under different initial wettability conditions to analyse EWPF performance in weak, moderate, and strong oil-wet mediums. Capillary numbers and a corresponding reduction in Sor are estimated to develop a screening parameter. EW prepared by 10 times diluted Caspian seawater spiked with optimized active ions has caused a 40-55o reduction in contact angle, making the rock more water-wet. Sor after waterflooding is 25% higher in a strong oil-wet carbonate sample in contrast with a weak oil-wet condition, implying such reservoirs are appropriate candidates for EWPF application. Ion-tuned water flooding has provided 8% of OOIC incremental recovery in strong oil-wet medium while it has given a negligible recovery in the weak oil-wet case. Despite having similar capillary numbers, EWPF has resulted in a 16% more reduction in Sor in the strong oil-wet system compared to the weak oil-wet system. This study presented a preliminary screening criterion for EW-based hybrid methods by considering the initial wettability of a reservoir. The results show that the hybrid EWPF method can reduce Sor more than that predicted by capillary desaturation curves. Hence, it has a higher capillary desaturation tendency and can be successfully applied to carbonate formations that are not water wet.
AB - Residual oil saturation (Sor) after waterflooding is high in carbonate reservoirs, due to the wettability state, making them a lucrative candidate for novel enhanced oil recovery (EOR) methods such as engineered water/polymer flooding (EWPF). Initial wettability for such reservoirs must be considered during the preliminary screening for an effective EWPF application. This experi mental study investigates the carbonate initial wettability criteria to achieve a successful EWPF design. Contact angles are measured at 80oC to evaluate the temperature effect on wettability shift by engineered water (EW). Coreflood tests are conducted under different initial wettability conditions to analyse EWPF performance in weak, moderate, and strong oil-wet mediums. Capillary numbers and a corresponding reduction in Sor are estimated to develop a screening parameter. EW prepared by 10 times diluted Caspian seawater spiked with optimized active ions has caused a 40-55o reduction in contact angle, making the rock more water-wet. Sor after waterflooding is 25% higher in a strong oil-wet carbonate sample in contrast with a weak oil-wet condition, implying such reservoirs are appropriate candidates for EWPF application. Ion-tuned water flooding has provided 8% of OOIC incremental recovery in strong oil-wet medium while it has given a negligible recovery in the weak oil-wet case. Despite having similar capillary numbers, EWPF has resulted in a 16% more reduction in Sor in the strong oil-wet system compared to the weak oil-wet system. This study presented a preliminary screening criterion for EW-based hybrid methods by considering the initial wettability of a reservoir. The results show that the hybrid EWPF method can reduce Sor more than that predicted by capillary desaturation curves. Hence, it has a higher capillary desaturation tendency and can be successfully applied to carbonate formations that are not water wet.
KW - engineered water
KW - enhanced oil recovery
KW - hybrid methods
KW - polymer flooding
KW - waterflooding
KW - wettability
UR - https://www.scopus.com/pages/publications/85144631980
UR - https://www.scopus.com/pages/publications/85144631980#tab=citedBy
U2 - 10.11159/iccpe22.125
DO - 10.11159/iccpe22.125
M3 - Conference contribution
AN - SCOPUS:85144631980
SN - 9781990800108
T3 - Proceedings of the World Congress on Mechanical, Chemical, and Material Engineering
BT - Proceedings of the 8th World Congress on Mechanical, Chemical, and Material Engineering, MCM 2022
A2 - Qiu, Huihe
A2 - Zhang, Yuwen
A2 - Iasiello, Marcello
PB - Avestia Publishing
T2 - 8th World Congress on Mechanical, Chemical, and Material Engineering, MCM 2022
Y2 - 31 July 2022 through 2 August 2022
ER -