Kinetics of Biomass Pyrolysis:  a Reformulated Three-Parallel-Reactions Model

Abstract

The thermal decompositions of sugarcane bagasse and waste-wood samples are studied using thermogravimetric analysis. Assuming the addition of three independent parallel decompositions, these corresponding to three pseudocomponents linked to the hemicellulose, cellulose, and lignin, the weight loss associated with the pyrolysis process is simulated. First, an irreversible firstorder reaction model is assumed for each pseudocomponent. Results show that the modelsimulated curves do not fit well to the experimental data. Consequently, a further kinetic study is carried out for the pure lignin (Kraft alkali lignin), which demonstrates that the pyrolysis of lignin is better described by a third-order reaction rate law. The reformulation of the lignin kinetic model, and its subsequent implementation in the summative model (for the third pseudocomponent), has allowed one to reach a good agreement between simulated and experimental data.

Thermogravimetric and Reaction Kinetic Analysis of Biomass Samples from an Energy Plantation

“…A wide range of activation energies has been reported in the literature of biomass materials. 10,[12][13][14][15][16][17][18][19][20][21][22][23]40 The Details on the Handling of Parameters m() and T. As described above, the magnitude of the m() and T parameters were constrained into physically meaningful ranges by choosing appropriate  values in eq 8.…”

“…Usually the mass loss or mass loss rate is described by models assuming biomass as sum of its constituents or sum of pseudocomponents. 10,[12][13][14][15][16][17][18][19][20][21][22][23] In the present paper, we study the thermal behavior of young shoots obtained from a short-rotation experimental energy plantation in Hungary. The cultivation of fast growing species is considered as a viable source for energy.…”

Thermogravimetric Study of Biomass Pyrolysis Kinetics. A Distributed Activation Energy Model with Prediction Tests

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] The biomass fuels and raw materials contain a wide variety of pyrolyzing species. Even the same chemical species may have different reactivity if their pyrolysis is influenced by other species in their vicinity.…”

Advances in Thermochemical Conversion of Biomass—Introduction

“…Numerous kinetic calculations can be found in the literature for the thermogravimetric experiments of biomass samples with very diverse results [28][29][30][31][32][33][34]. The kinetic models generally assume that the isothermal gas or liquid phase models can be applied for the dynamic experiments.…”

“…It is frequently supposed in the kinetic models that the thermal decomposition of the biomass components takes place independently from each other. The three-component mechanism with linear or nonlinear dependence on the species concentrations, for the volatile fractions of the pseudocomponents hemicellulose, cellulose and lignin, is widely applied [28][29][30][31][32][33] to describe the dynamic thermogravimetric curves of wood/biomass devolatilization. The first pseudocomponent is associated with the shoulder and the second one with the peak of the DTG curve, whereas the lignin pseudo-component decomposes slowly over a very broad range of temperatures.…”