Correlations of kinetic parameters in biomass pyrolysis with solid residue yield and lignin content

A kinetic analysis of the pyrolysis of various types of biomass (trunk, bark, leaf, shell, herbage, food dregs, and polysaccharide) as well as synthetic biomass consisting of cellulose and lignin was performed using thermogravimetric analysis data. The reaction rates of biomass pyrolysis were found to be expressed simply by a single nth-order reaction model. The kinetic parameters (frequency factor k₀, activation energy E, and reaction order n) were estimated first by differentiating the thermogravimetric curves and then by the nonlinear estimation method. The rate parameters of the pyrolysis of both 38 biomass samples and 9 synthetic biomass samples were successfully correlated in terms of the solid residue yield ω; charts are presented showing the correlations. Furthermore, a linear correlation was found between ω and the lignin content L in the woody biomass. This allows the kinetic parameters of biomass pyrolysis to be estimated using the value of ω, which is obtained from thermogravimetric measurements or estimated from the value of L for the biomass feedstock.