Computational Modelling of Imbert Type Downdraft Biomass Gasifier using CFX

Concern over the depletion of fossil fuels in the near future, increasing awareness about environmental pollution and need for energy conservation have proved that biomass is one of the most promising renewable sources of energy. However, efficient processes are required to convert this sources into useful one. So, gasification technology enables the conversion of these sources into a combustible gases, mechanical power and electrical energy. The quantity and quality of biomass differs from place to place. Therefore, designing a gasification technology for a remote areas needs more theoretical and experimental studies. The goal of this article is to develop a comprehensive and predictive kinetic model for the pyrolysis process in a downdraft gasifier, which is predominantly used in many places for biomass gasification. The volatiles and gases released during the pyrolysis process were assumed to crack down further into equivalent amounts of secondary products. In addition to this, a 30kWth downdraft biomass gasifier was modeled and analyzed using the CFX package. Experimental study were carried out on the same gasifier for further validation. The predicted results shows the temperature and mass fraction of combustible products at the outlet of the gasifier for various equivalence ratios.