PYROLYSIS GASIFICATION OF WOOD IN A PRESSURIZED FLUIDIZED-BED REACTOR

The paper deals with pyrolysis and steam gasification of wood in a pressurized fluidized bed reactor. The objective is to study the effect of the treatment conditions on the yield and the reactivity of char. The work shows that in the studied range of the experimental conditions the yield of char is influenced by neither the treatment temperature nor the pressure (650-710-degrees-C and 0.34-1.0 MPa). The principal interest is focused on the reactivity of the char in the reaction with steam. It is shown that prolonged exposure of char to high temperature has a negative effect on its reactivity in steam gasification. Char produced by pyrolysis of wood in nitrogen is much less reactive in the following gasification reaction with steam compared to the char produced in simultaneous pyrolysis/gasification of wood in the presence of steam.