Syngas production and combustion characteristics in a biomass fixed bed gasifier with cyclone combustor

Syngas production using double throat downdraft gasifier was characterized through full gas production range of 25-250 m3/h. The gasifier was able to produce ignitable syngas in a wide range of air fuel (AF) equivalence ratio (λ) of 0.3-0.4. Syngas combustion stability was characterized in a cyclone combustor. Stable combustion was achieved from lean fuel air (FA) equivalence ratio condition (φ = 0.49) to the rich combustion limit (φ = 1.25). Thermal power from the combustor was recovered by an annular tube heat exchanger to demonstrate a simple and efficient way of hot air production from biomass fuels. The hot air production configuration was characterized and the optimum operation condition was found to be at (φ = 0.68) lean combustion. This configuration can produce 36 kWth of hot air with overall efficiency of 46% and NOx and CO emissions below 140 ppm.