| Abstract
| - An apparatus for the fast pyrolysis of biomass is designed and set up to simulate the fastheating rate in the fluidized bed. The features of biomass fast catalytic pyrolysis in the apparatusare studied, whereas the kinetics model of biomass catalytic pyrolysis is presented. The resultsshow that both calcined dolomite and a nickel-based catalyst can elevate the hydrogen contentgreatly. The nickel-based catalyst has a stronger effect, and the hydrogen content is almostdoubled. The content of methane (CH4) can be greatly reduced through the use of nickel-basedcatalysts. Calcined dolomite can also decrease the content of CH4, to a smaller extent. A simplifiedmodel is presented, in which the entire process is treated as a single reaction. It assumes thatbiomass first decomposes to gaseous products, tars, and chars via three competitive reactionsand then tars go through a second cracking reaction to produce gases and chars. Through theproposed model, the calculated data fit well with the experimental data obtained from pyrolysistests of pine sawdust, lignin, and cellulose. The calculated reaction order is in the range of n =0.66−1.57. It is concluded that calcined dolomite must be used at a temperature of >800 °C.
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