2009 Volume 88 Issue 1 Pages 50-57
High temperature gasification experiment of woody biomass was carried out in an entrained down flow gasifier. In this experiment, characteristics of gasification residue in a high temperature gasification process were clarified. The highest temperature of gasifier was over 1273 K. Gasification experiment was conducted at different feed stock feeding rates, and gasification residue was collected during the gasification experiment at various dust collection points. Collection point of gasification residue was the gasifier exit, gasifier bottom, cyclone and bag filter of the gasification unit. Characterization of residue was conducted by chemical composition, particle diameter and particle shape. Temperature distribution in the gasifier and produced gas composition was monitored during the gasification experiment. Chemical composition of collected gasification residue was different at different dust collection points. Ash content was the highest in the gasifier bottom residue, and fixed carbon content was the highest in the bag filter residue. Particle diameter and observed particle shape was also different at different dust collection points. Gasification temperature increased with increasing the feeding ratio, chemical composition and particle diameter of residue was changed drastically. Ash ratio increased in the gasifier bottom, and fixed carbon ratio increased in the bag filter. But the differences in particle shapes collected at the same dust collection point were not significant. Calculated carbon conversion values didn't show the big difference in different experimental conditions, but gasification behavior in the gasifier was different, and soot generation increased with increasing the gasification temperature.
