Conformance Control in Heterogeneous Oil Reservoirs with Polymer Gels and Nano-Spheres

Abstract

In many oil fields, water is injected into a reservoir to displace oil to the production wells. During the injection process, oil is pushed by water towards production wells which have a lower pressure than the rest of the reservoir. If the reservoir is homogeneous, then a good sweep efficiency of the water flood process is expected. However, most oil reservoirs are stratified and that creates a permeability contrast along the whole height. High permeable layers take most of the injected water resulting in lower sweep efficiency of the other layers. The water breaks through the high permeable zones, significantly increasing the water cut of the produced fluid. Excessive produced water has to be treated in surface facilities which increase the costs of the extraction process. Another disadvantage of the low sweep of a reservoir is a significant amount of remaining oil behind the displacement front...