Abstract
To understand the behavior of the down-flow gasifier for woody biomass, the optimum operation conditions and gasification characteristics were studied. Pulverized wood powder sieved under the 60 mesh was used for gasification fuel in this paper. The CO_2 concentration was increased 10% by the oxidation reaction with increasing the temperature 200 K at the temperature of 1600K. However, total production of CO and H_2 were moderate change and it was around 60%, 40% for CO and 20% for H_2 in the total flue gas. CH_4,C_2H_2 and C_2H_4 were under 5%, 2%, 2%, respectively at the same condition. Therefore, combustible gas (CO+H_2+CH_4) was over 60% and the gas-heating value was 5.9-8.9 MJ/m^3N. Carbon gasification conversion and cold gas efficiency achieved 90% and 50% respectively at the temperature of 1600K. Choking trouble by biomass tar at the bag filter was controlled better by injecting inert absorbent.
