Open-source kinetic modelling of downdraft biomass gasification in Python: validation and parametric analysis of syngas quality

An open-source, kinetic model for downdraft biomass gasification was developed in Python to provide a transparent and reproducible reactor-scale framework. The approach integrates coupled mass and energy balances with a 26-reaction kinetic set describing drying, multi-stage pyrolysis, oxidation, reduction, and tar cracking in a plug-flow configuration. Validation against laboratory-scale experimental data for Scots pine under air-blown conditions yielded an average mean absolute percentage error (MAPE) of 3.03% and a root mean square error (RMSE) of 0.6693 for major syngas species (CO, CO 2 , H 2 , CH 4 ). Additional validation using Miscanthus briquettes and rubber wood confirmed predictive robustness without parameter re-tuning, maintaining RMSE values below the established acceptance threshold (RMSE