Devolatilization behaviour and pyrolysis kinetic modelling of Spanish biomass fuels

The basic pyrolysis behaviour of eight different biomass fuels has been tested in a thermogravimetric analyser under dynamic conditions (5, 20 and 50 A degrees C min(-1) heating rates) from room temperature up to 1,000 A degrees C. Their decomposition was successfully modelled by three first-order independent parallel reactions, describing the degradation of hemicellulose, cellulose and lignin. Hemicellulose would be the easiest one to pyrolyse, while lignin would be the most difficult one. Experimental and calculated results show good agreement. The reactivity of the different biomass type functions of various thermal, kinetic and composition parameters are discussed. The effect of the heating rate on pyrolysis behaviour was studied, and a comparison between slow and fast heating rate reveals a small displacement of the DTG profiles to higher temperatures. The heating rate not only affects the highest mass loss rate temperature but also influences the mass loss rate value.