TY - GEN
T1 - An experimental study of acid matrix treatment performance on shale core samples
AU - Khalil, Rayan E.
AU - Mansour, Ahmed
AU - Gamadi, Talal
N1 - Publisher Copyright:
Copyright 2017, Society of Petroleum Engineers
PY - 2017
Y1 - 2017
N2 - Experimental and numerical studies have demonstrated that there is great potential of enhancing the oil recovery from tight formations. This study investigated the effect of acid matrix treatment by applying gas flooding on the core samples before and after the treatment. The aim of the acid stimulation treatment was to improve the low-permeability of the cores. Four core samples (0.5 in, 1.0 in, 1.5 in, and 2.0 in) from an outcrop of the Eagle Ford formation were used in this study. Permeability was measured before and after the acid treatment. The cores were CT-scanned to identify natural fractures. Different gas injection pressures were used to study the oil recovery and the time needed to penetrate through core samples. Furthermore, a solubility test was applied to identify the optimal acid concentration. The cores were re-scanned after the acid flooding treatments to detect any change. Gas flooding was applied to acidized core samples to detect changes in penetration time and recovery factor. A solubility test demonstrated that 15% of HCL was the optimal acid concentration for the Eagle Ford formation. The study showed the porosity, permeability, recovery factor, and penetration time before and after the acidizing treatment. Permeability was enhanced from 1.04 nanodarcies to 2.10 microdarcies. Furthermore, the study showed the effect of core length on penetration rate (in/min) of gas flooding and the recovery factor at each injecting pressure. The penetration time in this study varied from 207 to 112 minutes/inch when the injecting pressure increased from 1500 to 2500 psi. After acidizing, however, the penetration rate decreased to 8.4 minutes/inch using flooding of 300 psi. The CT scan showed improvement of the micro fracture width.
AB - Experimental and numerical studies have demonstrated that there is great potential of enhancing the oil recovery from tight formations. This study investigated the effect of acid matrix treatment by applying gas flooding on the core samples before and after the treatment. The aim of the acid stimulation treatment was to improve the low-permeability of the cores. Four core samples (0.5 in, 1.0 in, 1.5 in, and 2.0 in) from an outcrop of the Eagle Ford formation were used in this study. Permeability was measured before and after the acid treatment. The cores were CT-scanned to identify natural fractures. Different gas injection pressures were used to study the oil recovery and the time needed to penetrate through core samples. Furthermore, a solubility test was applied to identify the optimal acid concentration. The cores were re-scanned after the acid flooding treatments to detect any change. Gas flooding was applied to acidized core samples to detect changes in penetration time and recovery factor. A solubility test demonstrated that 15% of HCL was the optimal acid concentration for the Eagle Ford formation. The study showed the porosity, permeability, recovery factor, and penetration time before and after the acidizing treatment. Permeability was enhanced from 1.04 nanodarcies to 2.10 microdarcies. Furthermore, the study showed the effect of core length on penetration rate (in/min) of gas flooding and the recovery factor at each injecting pressure. The penetration time in this study varied from 207 to 112 minutes/inch when the injecting pressure increased from 1500 to 2500 psi. After acidizing, however, the penetration rate decreased to 8.4 minutes/inch using flooding of 300 psi. The CT scan showed improvement of the micro fracture width.
UR - http://www.scopus.com/inward/record.url?scp=85088405055&partnerID=8YFLogxK
U2 - 10.2118/187478-ms
DO - 10.2118/187478-ms
M3 - Conference contribution
AN - SCOPUS:85088405055
T3 - Society of Petroleum Engineers - SPE Liquids - Rich Basins Conference - North America 2017
BT - Society of Petroleum Engineers - SPE Liquids - Rich Basins Conference - North America 2017
PB - Society of Petroleum Engineers
T2 - SPE Liquids - Rich Basins Conference - North America 2017
Y2 - 13 September 2017 through 14 September 2017
ER -