In this work, the dispersion of butane in heavy oil and bitumen is experimentally determined during the Vapex process with varying drainage heights. The experiments are performed at constant temperature using butane as solvent at the dew point pressure. Cylindrical models with different heights packed with unifrom mixture of bitumen and glass beads are used. From the experimental data, the production rate dependency towards the drainage height is evaluated along with determination of butane gas solubility, live oil density and vicosity.A mathematical model is developed to simulate live oil production rates. A variable metric method in multi dimensions is used to optimally determine concentration dependent dispersion coefficient as well as solvent mass fraction at liquid gas interface by matching up experimental and predicted live oil production rates. A computational algorithm is developed to solve a set of models simultaneously to evaluate effect of drainage height on dispersion of solvent gas.