Energy and exergy analysis of thermo-chemical gasification of sawdust using thermodynamic equilibrium model

Biomass, the largely available renewable energy source, will be a future viable solution for world's energy crisis. A stoichiometric thermodynamic equilibrium model of air-steam gasification of saw dust in fluidized bed is developed in the present work. The model considers both char conversion and tar formation and predicts the product gas composition, and energy and exergy efficiencies at different operating conditions using MATLAB software. For a steam to biomass ratio of unity, maximum mole fraction of hydrogen is found to be 34.68% at a temperature of 1500 K and equivalence ratio of 0.15, with an exergy efficiency of 75.44%.