Biomass Catalytic Steam Gasification Thermodynamics Analysis and Reaction Experiments in a CREC Riser Simulator

Abstract

A thermodynamic equilibrium model based on evaluations involving C, H, and O element balances and various product species up to C6 hydrocarbons is reported in this study. This model establishes the effects of biomass composition, temperature, and steam on the various gas product molar fractions. On this basis, most significant parameters determining the chemical interconversions and distribution of chemical species are identified. On the basis of the proposed equilibrium model and using glucose as a model biomass species [C6H12O6], an optimum gasification temperature close to 800 °C and a steam/biomass ratio between 0.5 and 0.7 g/g is established. This study has the special value of comparing thermodynamic equilibrium predictions with experimental data obtained in a CREC riser simulator using a fluidizable Ni−Al2O3 catalyst. Results are relevant for scaled-up gasifiers. They show that for reaction times longer than 30 s chemical species are essentially equilibrated and that the proposed model does provide...