Modelling pyrolysis with dynamic heating

In literature, the reaction kinetic of pyrolysis process is often determined and modelled under constant heating rates. In reality, the heating rate of an industrial pyrolysis process is difficult or often not necessary to be kept constant. The variation of heating rate at different reaction stages, termed “dynamic heating”, governs the pyrolysis performance such as production rate, energy consumption, product quality, etc. In this work, pyrolysis progress with dynamic heating is being studied. The rate and reaction heat of tyre pyrolysis at different heating rates are obtained experimentally. A transient model considering the effect of dynamic heating was then developed and compared with the conventional static heating model. Results show that a higher heating rate favours the production of volatiles and shifts the overall pyrolysis heat flow to more endothermic. The significance of the dynamic heating model was observed for processes with large feed size and/or with high heating rate.

► A higher heating rate favours the production of volatiles.
► A higher heating rate shifts the overall pyrolysis heat flow to more endothermic.
► Dynamic heating consideration is needed for modelling large feeds pyrolysis.
► Dynamic heating consideration is needed for modelling high heating rates pyrolysis.