In this study, a process model for an auger-style biomass pyrolysis reactor is developed to use as a tool in process optimization and scaleup. The plug-flow model for both solid and gas phases is assumed. A comparison between the kinetic models widely used in the literature to the experimental data was performed to determine the "best" kinetic model for our system. The transport equations for each phase are combined with the kinetic model to predict bio-oil, char, and non-condensable gas yields. The applied model was validated with experimental data from a 2-4 kg/h pilot-scale auger reactor. This reactor uses steel shot as a heat carrier and without carrier gas. The results show good agreement between experimental data and model prediction. The model was used to predict the yield of bio-oil as a function of the temperature, feed flow rate, and reactor pressure. These simulations indicate that the model is a useful tool in design and scaleup of auger-type pyrolysis reactors using a heat carrier.