Improved Efficiency of Miscible CO2 Floods and Enhanced Prospects for CO2211 Flooding Heterogeneous Reservoirs

摘要

This work will examine three major areas in which CO(sub 2) flooding can be211u001eimproved: fluid and matrix interactions, conformance control/sweep efficiency, 211u001eand reservoir simulation for improved oil recovery. The first full quarter of 211u001ethis project has been completed. We began examining synergistic affects of mixed 211u001esurfactant versus single surfactant systems to enhance the properties of foams 211u001eused for improving oil recovery in CO(sub 2) floods. The purpose is to reduce the 211u001econcentration of surfactants or finding less expensive surfactants. Also, we are 211u001eexamining the effect of oil saturation on the development of foam in CO(sub 2)-211u001esurfactant solution systems. CO(sub 2) flooding of low permeability, vugular, and 211u001efracture reservoirs are another major thrust of this project. Work conducted this 211u001equarter involved simulating gravity stable floods using large core samples; 211u001eresults showed excellent recovery in a low permeability vugular core.