Wide-ranging distributed activation energy models for pyrolysis of woody and agricultural biomass

Pyrolysis of biomass has been studied in thermogravimetric analyzers (TGA), wire-mesh reactors (WMR), laminar flow reactors (LFR), and single particle reactors (SPR), but no simple kinetic models are available that are able to capture mass loss rates over a wide range of conditions. In the present work, the distributed activation energy model (DAEM) has been parameterized for pine wood and straw, based on literature data for pyrolysis of small particles of pine and straw under kinetic control in TGA and WMR for heating rates of 0.67–1000 K s −1 . The DAEM kinetics for pyrolysis were implemented in a particle model that also accounted for water evaporation and heat transfer limitations. The combined model captured experimental results for pyrolysis of pine at heating rates of 0.5–10 5 K s −1 . Even though application of the model for other wood types and larger particle sizes showed reasonable agreement, DAEM kinetics for pine should be used cautiously for hardwood. Validation of the straw DAEM kinetics was difficult due to the scarcity of experimental data at increased heating rates (10 3 –10 5 K s −1 ), but the model performed well for WMR results obtained at a heating rate of 500 K s −1 and pyrolysis temperatures of 1073–1273 K.