Oil and Water Flooding after Gel Placement

The imbibition and drainage displacements performed after gel placement address the primary goal of this work—to establish the mechanism for disproportionate permeability reduction for Cr(IIII)-acetate-HPAM gels. The most important conclusion from our earlier work was that oil injection effectively reduced gel volume (e.g., by dehydration) in many pathways that were utilized by oil before gel placement.1,3,7 This conclusion was confirmed in this work. We define gel “dehydration” as a process of removing water from the gel by imposing a pressure gradient on the gel. Necessarily, the polymer must become more concentrated by the dehydration process and its volume reduced.