Carbon dioxide flooding has been recognized as an efficient means of recovering oil. However, the efficiency is marred due to the unfavorable mobility ratio between CO2 and the oil to be displaced and die poor sweep efficiency resulting from the heterogeneity of the reservoir. The goals of this study are to develop a quick and efficient method to explore the possible application of foam in mobility control, and to identify available surfactant in such an application to increase the sweep efficiency, and therefore the oil recovery. Some of the results from this study show that mobility of CO2 is significantly reduced by using the foam. In addition to that, a possible characteristic of foam in selective mobility reduction (SMR) is also observed in some of the tests in which the CO2-foam mobility was found to be lower in higher permeability rock samples than that in lower permeability rock samples. In other words, the flow of foam is likely less mobile in a more permeable porous media than that in a less permeable region of the reservoir formation. This behavior is favorable to preserve the uniformity of a flood front as it propagates through the rocks with nonuniform permeability. Based on limited data, however, the SMR is found to be dependent on flow rate and on the type of rocks when using the same surfactant.

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