Simulation of biomass gasification in downdraft gasifier for different biomass fuels using ASPEN PLUS

Biomass utilization through gasification could be a viable alternative energy source for meeting energy demands in decentralized manner. Thermodynamic equilibrium and other models have been proposed to explain and understand the complex biomass gasification process, design, simulation, optimization, and process analysis of gasifiers. Present paper deals with a comprehensive process model developed for biomass gasification in an atmospheric fixed bed rector using the ASPEN PLUS. The experimental facility of the gasifier developed by the authors has a provision for proper cooling and filtration system to derive satisfactory performance with low emissions. Thus the model developed using ASPEN PLUS is validated with experimental data obtained with four different types of feed stocks viz; babul wood, neem wood, mango wood, and bagasse. The model has well-predicted composition of H₂, CO, and CO₂ whereas it has under predicted the CH₄. The gasifier conversion efficiency was observed to be higher with babul wood when compared with other three types of wood due to its high carbon and H₂ and less ash concentrations.