TY - GEN
T1 - Potential of combining propane (LPG) hydraulic fracturing and chemical flooding in thin heavy-oil reservoirs
AU - Morsy, Samiha
AU - Sheng, James J.
AU - Soliman, Mohamed Y.
AU - Shahri, Mehdi
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2013
Y1 - 2013
N2 - Waterflooding in a viscous heavy-oil reservoir results in a very poor sweep efficiency because of an unfavorable mobility ratio. However, thickened waterflooding by polymer or gel might not be economic because of high concentrations of chemicals that must be added to achieve a favorable mobility ratio. Moreover, it is understood that thermal recovery cannot be used in thin heavy-oil reservoirs because of major heat loss to overburdened and underburned formations. In cases where an oil reservoir is under permafrost, thermal recovery methods might not be applicable because the injected heat could possibly cause permafrost to thaw. In this paper, it is proposed to inject chemicals (alkaline/surfactant) into a producer immediately after hydraulic fracturing with liquefied propane gas (LPG). The injected chemicals form an oil/water (O/W) microemulsion whose viscosity is much lower than that of the reservoir oil viscosity. When the producer is in production mode, oil is produced in the form of an O/W microemulsion. The interfacial tension between the microemulsion phase and excess oil phase will be very low. Thus, the residual oil saturation will be reduced owing to the increased capillary number. The created hydraulic fractures can provide better access to the reservoir, reduce the loss of the injected chemicals, increase the area of contact between the chemicals and reservoir oil, and improve sweep efficiency of the injected chemicals. The LPG will also work as a solvent during the fracturing phase, speeds up the chemical diffusion and reduce the heavy-oil viscosity around the fracture faces, which will accelerate chemical diffusion when injected after hydraulic fracturing. The chemicals are injected using a huff-and-puff process. Both horizontal and vertical wells can be treated using this process. Simulation results show that the production from such thin heavy-oil reservoirs is significantly accelerated, and the oil recovery factor can be improved up to 200%.
AB - Waterflooding in a viscous heavy-oil reservoir results in a very poor sweep efficiency because of an unfavorable mobility ratio. However, thickened waterflooding by polymer or gel might not be economic because of high concentrations of chemicals that must be added to achieve a favorable mobility ratio. Moreover, it is understood that thermal recovery cannot be used in thin heavy-oil reservoirs because of major heat loss to overburdened and underburned formations. In cases where an oil reservoir is under permafrost, thermal recovery methods might not be applicable because the injected heat could possibly cause permafrost to thaw. In this paper, it is proposed to inject chemicals (alkaline/surfactant) into a producer immediately after hydraulic fracturing with liquefied propane gas (LPG). The injected chemicals form an oil/water (O/W) microemulsion whose viscosity is much lower than that of the reservoir oil viscosity. When the producer is in production mode, oil is produced in the form of an O/W microemulsion. The interfacial tension between the microemulsion phase and excess oil phase will be very low. Thus, the residual oil saturation will be reduced owing to the increased capillary number. The created hydraulic fractures can provide better access to the reservoir, reduce the loss of the injected chemicals, increase the area of contact between the chemicals and reservoir oil, and improve sweep efficiency of the injected chemicals. The LPG will also work as a solvent during the fracturing phase, speeds up the chemical diffusion and reduce the heavy-oil viscosity around the fracture faces, which will accelerate chemical diffusion when injected after hydraulic fracturing. The chemicals are injected using a huff-and-puff process. Both horizontal and vertical wells can be treated using this process. Simulation results show that the production from such thin heavy-oil reservoirs is significantly accelerated, and the oil recovery factor can be improved up to 200%.
UR - http://www.scopus.com/inward/record.url?scp=84883378921&partnerID=8YFLogxK
U2 - 10.2118/165450-ms
DO - 10.2118/165450-ms
M3 - Conference contribution
AN - SCOPUS:84883378921
SN - 9781627486286
T3 - Society of Petroleum Engineers - SPE Heavy Oil Conference Canada 2013
SP - 780
EP - 792
BT - Society of Petroleum Engineers - SPE Heavy Oil Conference Canada 2013
PB - Society of Petroleum Engineers
Y2 - 11 June 2013 through 13 June 2013
ER -