The aim of this work is to analyze the optimal operating conditions for fast biomass pyrolysis. The operating conditions required to maximize the yield of liquid products are investigated and discussed on the basis of a comprehensive mathematical model of wood/biomass devolatilization. Crucial issues are the fast and complete heating of biomass particles to reduce char formation and the rapid cooling of released products to reduce the role of secondary gas-phase pyrolysis reactions. Chemical kinetics as well as heat- and mass-transfer phenomena play an important role in this process; thus, a comprehensive kinetic model is applied. The proposed model, when compared to the majority of other devolatilization models, attempts to characterize pyrolysis reactions with a lumped stoichiometry using a limited number of equivalent components to describe not only gaseous products but also tar species. Model predictions are compared to experimental measurements not only with further validation in mind but also princi...