Energy Sources Part A-recovery Utilization and Environmental Effects, Vol.33, No.21, 1993-2004, 2011
An Experimental Investigation of Fracture Physical Properties on Heavy Oil Displacement Efficiency during Solvent Flooding
This work is concerned with the role of geometrical properties of fractures on oil displacement efficiency during solvent injection to heavy oil. Here, a series of solvent injection processes were conducted on one-quarter five-spot fractured micromodels that were initially saturated with the heavy oil, at a fixed flow rate condition. The oil recovery was measured using image analysis of the continuously provided pictures. The results show that for the range of experiments performed here, the maximum oil recovery happens at a fracture orientation angle of 45 degrees. Also, increasing the number of fractures leads to a higher oil recovery factor by solvent in 45 degrees, while it does not change significantly for the case of a 90-degree inclination. By increasing the fracture spacing, the oil recovery factor decreased. When fractures are distributed along the mean flow direction, oil recovery is higher than the case where the fractures are more dispersed and are not in the mean flow direction. In the presence of discontinuous fractures, the oil recovery factor decreases in comparison with the case of continuous fractures. The results of this work might be helpful for better understanding the role of fractures during miscible injection processes, which might be used to develop new mathematical models in such a reservoir.
Keywords:five-spot micromodel;fractured medium;fracture geometrical properties;heavy oil;solvent flooding