Effect of Fuel Properties on Reaction Front in an Open-Top Downdraft Gasifier

Abstract

The effect of biomass physical properties, i.e., particle size, particle density, and moisture content on propagation rate at various air mass fluxes is studied. The biomass fuel samples used in the study are Bamboo (Bambusoideae) and Krishnachura (Delonix regia). The increase in moisture content decreases the reaction front propagation because the endothermicity of bed increases and peak bed temperature decreases. The peak front propagation rate for Bamboo and Krishnachura is 0.14 mm/s and 0.24 mm/s, respectively. The front propagation rate decreases as the particle size increases for the same operating conditions. The larger particle size leads to incomplete pyrolysis and thus, affects the front propagation and gasification performance. Particle density has an inverse relationship with flame propagation. The result of this study provides an understanding on the effect of biomass physical properties on the front propagation rate.