EFFECT OF STEAM TO BIOMASS RATIO ON GASIFICATION OF BIOMASS JH Moon, YK Sung, BR Bang, UD Lee* KITECH, South Korea uendol@kitech.re.kr The 33rd International Symposium on Combustion, Beijing, China, August 1-6, 2010. Introduction Results In this study, effect of steam on biomass gasification was investigated in a tube furnace. Korean pine woodchip was used as a feedstock, and syngas compositions and yield were monitored as a function of time by varying temperature and steam to biomass ratio. <700℃ Gas composition> <800℃ Gas composition> <900℃ Gas composition> Syngas is mainly composed of H2,CO,CO2,CH4 The gas yield of steam gasification cases are much lager than pyrolysis H2 yield is significantly affected by the steam and gasification temperature <Gas rate at different temperature> The gasification process can be separated in devolatization and char gasification Steam has little effect on devolatization process but it can give a significant effect on char gasification <Carbon conversion> Carbon conversion is significantly affected by the steam and gasification temperature Materials and methods Materials: Korean pine woodchip (Average size: 5mm) Methods Biomass pyrolysis and gasification principal Proximate analysis Ultimate analysis(Dry basis) LHV Moist. VM Ash FC C H N O S Wt% mg/kg kcal/kg 6.4 75.9 0.3 17.4 50.8 5.4 0.0 43.6 61.8 4,518 Batch type Sic electric heater Continuous gas analyzer(ND-IR) Dry gas meter Cold traps followed by a ceramic filter Sample amount: 20g Steam/Biomass ratio(S/B) : Pyrolysis, 1/1, 2/1, 3/1 Purging gas: N2 1L/min Temperature(℃): 700,800,900 Conclusion High concentration H2 is generated at high temperature and increase of S/B ratio when the biomass steam gasify. H2 concentration is significantly increased above 800℃. The gasification process can be separated in devolatization and char gasification. Reaction time of devolatization stage at high temperature is shorter than lower temperature. Amount of syngas from char gasification is increased when adding steam. Reaction time of biomass pyrolysis is about 2 min but on the other hand it is about 18 min at steam gasification and H2 concentration is significantly incresed.