Influence of particle size and kinetic parameters on tire pyrolysis

One of the most important parameters that can significantly affect the cost of the tire pyrolysis process is the time needed for thermal decomposition of the tire material. In this work, the influence of particle size and kinetics of thermal decomposition on the pyrolysis time was studied. The apparent kinetic parameters of tire thermal decomposition were estimated using three different approaches based on thermogravimetry measurements. In separate experiments, tire particles with different sizes were pyrolyzed under isothermal conditions in a laboratory flow reactor at different residence times of the particles in the reactor and the data recorded were employed in the determination of tire conversion during the thermal decomposition. A mathematical model of tire pyrolysis considering heat conduction in the tire particles was developed. All three types of estimated kinetic parameters were used to determine the conversion behavior at isothermal conditions and the results were compared with experimental data obtained. The model was used also to calculate the pyrolysis time in an industrial scale reactor at different temperatures and particle sizes.