In this study, the entrained flow gasification (EFG) of Kentucky coal and wood waste had been investigated using detailed kinetics-based ASPEN Plus model and experimental diagnostics. The experimental investigation was conducted in the air-blown atmospheric drop tube experimental facility furnace. The exit gas composition at different equivalence ratios was obtained to validate the developed ASPEN Plus model. In addition, the scanning electron microscopy (SEM) images of the char were observed along the gasifier to determine the behavior of the feedstock subjected to gasification and to select proper char gasification models. The model takes into account the passive heating through moisture release, devolatilization, volatile combustion and char gasification. It made the investigation of the gasification process and running sensitivity studies practically feasible as current equilibrium and high fidelity coupled thermo-chemical-flow models are insufficient or pertaining much complexity to use. The model compares reasonably well with the experimental data obtained in this work and is been used to carry out sensitivity study. A rise in the diameter and height sizes lead to an increase in the mole fraction of CO and H2 throughout the length of the gasifier, an opposite trend was observed for the CO2 and H2O composition. It was also observed that the mole fraction of the syngas was lower for the biomass waste compared to the baseline coal as this is attributed to the higher oxygen content (43.62%) and lower carbon content (49.41%) of the waste biomass compared to coal. (C) 2014 Elsevier Ltd. All rights reserved.