A Tar Conversion Model for Fluidized Bed Biomass Gasifiers

Abstract

A comprehensive tar conversion model for biomass gasification has not been developed up to date due to the great deal of processes involved, whose stoichiometry and kinetics are not well known. Therefore, simplified schemes of reactions are assumed in existing models, reducing their capability to predict the tar composition in the gas. In this work a model to predict tar composition from wood gasification was developed. The model takes into account both tar generation from the fuel and secondary transformations of the gas in the gasifier, mainly focused on conditions applicable to fluidized beds. The model comprises a limited number of tar compounds and reactions representing the main tar species and conversion mechanisms, which stoichiometry and kinetics are based on literature data. Comparison with measurements from literature data is presented to discuss the applicability of the model.