Experimental confirmation of analytical composition routes in three-phase partially miscible flow

In this paper effluent data from laboratory experiments are compared with analytical composition routes and profiles for three-phase partially miscible flow of three-component mixtures. Core flood experiments were run in vertical glass bead packs to achieve approximately one-dimensional displacements with stable displacement fronts. The displacements employed in this study include modest effects of dispersion, but dispersion does not substantially alter the composition routes. Complex analytical composition routes are developed by the method of characteristics (MOC) for one-dimensional, dispersion-free flow where up to three partially miscible flowing phases may be present. The exponents used in the relative permeability model were obtained by fitting profiles from one drainage (oil injection) and one imbibition (water/alcohol injection) displacement. The resulting parameters were used to construct the analytical solutions for the remaining displacements. Development of the analytical solutions to Riemann problems is outlined. Different parameters are obtained for the imbibition and drainage experiments, indicating that hysteresis occurs in the experiments. Comparison of the experimental results with the analytical solutions shows that the mathematical model captures the essential features of the experimental displacements. In the cases in which the analytical solutions fail to model accurately the physical displacements, the effect of simplifying assumptions in the model are examined.