Numerical simulation of foam injection in fractured carbonates - Quantifying the impacts of foam and reservoir properties

Foam can be used to enhance oil recovery by increasing the areal and lateral sweep, reducing gravity override and diverting the flow from to low permeable areas. In this study we matched two experimental data sets of foam injection in carbonate rocks that were conducted at different pressure and temperature to a numerical model. The aim to analyse how the resulting changes in foam properties affect the overall sweep efficiency in the presence of geological uncertainties that are typical for a fractured carbonate reservoir. In order to quantify how reservoir heterogeneity impacts foam injection at high/low temperature and pressure, and hence the field-scale recovery, we deploy the matched foam models in a reservoir simulation model that is a realistic analogue for the Arab D formation in Qatar. We use this simulation model to test the effect of foam properties, injection strategies, and reservoir properties to analyse the displacement processes and compare the overall sweep and recovery. To this end, foam yields significantly higher recovery factors compared to other EOR methods, in particular if the reservoir is heavily fractured, but the uncertainties in foam properties can affect recovery factors to the same degree as geological uncertainties.