Simulation analysis of biomass pyrolysis based on the improved chemical percolation devolatilization model with chain reaction dynamics

Abstract The complex composition and molecular structure of biomass lead to more complex and diversified chemical reactions in the pyrolysis. According to the structural characteristics of the reactants, this article simplifies the pyrolysis process and extends the research focus from the micro‐molecular elementary reactions to the macro reaction kinetics. The wheat straw is chosen as the investigated biomass, and the promoted chemical percolation devolatilization with modified pseudo‐grid and chain reaction kinetics pyrolysis models were constructed for predicting the pyrolysis characteristics. Under the condition of slow pyrolysis, by calculating the average difference between the collected calculated values and the corresponding experimental values, the prediction errors of bio‐char, bio‐oil, and gas production are in a reasonable range of <10%. Moreover, the reliability of the model is verified by comparing with the experimental thermogravimetric curve, which shows that the model could well predict the mass loss, product distribution, and component characteristics, and provides a reasonable prediction for the pyrolysis of biomass. However, the simplifications and assumptions about the model also lead to some deviations of the predicted values, which should be considered and improved in future research.