OBTAINING OF FUEL GAS FROM CATALYTIC CONVERSION OF RESIDUAL BIOMASS |
OBTAINING OF FUEL GAS FROM CATALYTIC CONVERSION OF RESIDUAL BIOMASS
Elena David*, Adrian Armeanu, Claudia Sandru, Violeta Niculescu
ABSTRACT In this paper is investigated the steam gasification method to obtain fuel gas using biomass wastes as raw material. Characteristics of steam gasification of two kinds of biomass (rapeseed oil cakes and walnut shells) at different heating rate (in the order of 10-20°C s-1) and different metal oxide catalysts (CaO, MgO and a mixture 50% CaO and 50% MgO) in a gas-solid concurrent down flow free-fall reactor were determined. The effects of steam/biomass (S/B) mass ratio (0.0-1.0 g/g) and reactor temperature (750-850°C) on the product yields and the compositions of product gas were determined. The experimental results show that the gas yields and the content of H2 in the gas increase with reactor temperature, while the yields of tar, char and the content of CO and CH4 in the product gas decrease. The presence of steam increases the gas yield and reduces the tar and char yields. Water-gas shift reaction determines greatly the gas compositions and H2 production at higher temperature. The effects of different catalysts, CaO, MgO and a mixture (50% CaO + 50% MgO), were also investigated. The mixt catalyst reveals a better performance in terms of catalytic activity of tar destruction than CaO, MgO catalysts and the consequential increase in the production of gases in thus a short vapor-catalyst contact time. This results demonstrate that the presence of steam and catalyst favors the tar decomposition and lead to increasing of hydrogen content in gas yield.
Keywords: residual biomass, steam gasification, catalytic conversion, H2-enriched gas.
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