TY - JOUR
T1 - Experimental and mathematical modeling studies on foamy oil stability using a heavy oil–CO2 system under reservoir conditions
AU - Zhou, Xiang
AU - Zeng, Fanhua
AU - Zhang, Liehui
AU - Jiang, Qi
AU - Yuan, Qingwang
AU - Wang, Jinjie
AU - Zhu, Guocai
AU - Huang, Xiaoliang
N1 - Publisher Copyright:
© 2019 Elsevier Ltd
PY - 2020/3/15
Y1 - 2020/3/15
N2 - This study experimentally and mathematically investigated the foamy oil stability of a heavy oil–CO2 system. Experimentally, a new test method employing a gas cap was applied to avoid the effect of oil coating. In total, seven experiments were carried out for the heavy oil–CO2 system, using the constant composition expansion process in a pressure/volume/temperature cell under different pressure depletion rates (1, 2, 4, 8, 16, 24, and 32 kPa/min). Foamy oil stability was monitored for each test, and phase behavior differences were analyzed among the different pressure depletion rates. Experimental results indicate that pseudo-bubble-point pressure decreases with increased pressure depletion rate, and the maximum relative volume of foamy oil increases with increased pressure depletion rate. This work further performed a mathematical modeling study, developing a new dynamic reaction rate model to history-match the foamy-oil-stability experimental results. A First-order Reaction was applied for the both gas transfer processes (solution gas transfers to dispersed gas and dispersed gas transfers to free gas). The mathematical model was developed to simulate changes of foamy oil volume, the reaction rate constants k1 (indicating gas phase transfer rate from solution gas to dispersed gas) and k2 (indicating gas phase transfer rate from dispersed gas to free gas) were determined using the developed model, and trends were identified for the reaction rate constants changing with pressure depletion rates. The mathematical modeling study shows that (1) reaction rate constants k1 and k2 increase with increased pressure depletion rate on the order of 0.001 min−1; (2) k2 is much more sensitive than k1; and (3) pressure depletion rate can be optimized to achieve more stable foamy oil behavior.
AB - This study experimentally and mathematically investigated the foamy oil stability of a heavy oil–CO2 system. Experimentally, a new test method employing a gas cap was applied to avoid the effect of oil coating. In total, seven experiments were carried out for the heavy oil–CO2 system, using the constant composition expansion process in a pressure/volume/temperature cell under different pressure depletion rates (1, 2, 4, 8, 16, 24, and 32 kPa/min). Foamy oil stability was monitored for each test, and phase behavior differences were analyzed among the different pressure depletion rates. Experimental results indicate that pseudo-bubble-point pressure decreases with increased pressure depletion rate, and the maximum relative volume of foamy oil increases with increased pressure depletion rate. This work further performed a mathematical modeling study, developing a new dynamic reaction rate model to history-match the foamy-oil-stability experimental results. A First-order Reaction was applied for the both gas transfer processes (solution gas transfers to dispersed gas and dispersed gas transfers to free gas). The mathematical model was developed to simulate changes of foamy oil volume, the reaction rate constants k1 (indicating gas phase transfer rate from solution gas to dispersed gas) and k2 (indicating gas phase transfer rate from dispersed gas to free gas) were determined using the developed model, and trends were identified for the reaction rate constants changing with pressure depletion rates. The mathematical modeling study shows that (1) reaction rate constants k1 and k2 increase with increased pressure depletion rate on the order of 0.001 min−1; (2) k2 is much more sensitive than k1; and (3) pressure depletion rate can be optimized to achieve more stable foamy oil behavior.
KW - Foamy oil stability
KW - Heavy oil–CO system
KW - Mathematical modeling
KW - Pressure depletion
KW - Reservoir condition
UR - http://www.scopus.com/inward/record.url?scp=85076314283&partnerID=8YFLogxK
U2 - 10.1016/j.fuel.2019.116771
DO - 10.1016/j.fuel.2019.116771
M3 - Article
AN - SCOPUS:85076314283
SN - 0016-2361
VL - 264
JO - Fuel
JF - Fuel
M1 - 116771
ER -