Kinetic modelling of tyre pyrolysis in a conical spouted bed reactor

A novel kinetic model has been proposed for the thermal pyrolysis of tyres. The model is based on a reaction scheme that considers an intermediate lump and parallel reactions for the formation of the different product lumps. Seven lumps have been taken, which are gas (C4), non-aromatic liquid (C5−C), aromatics (C), tar (C11+), char (low grade carbon black), intermediate and the original tyre. The kinetic data have been obtained in a pilot plant provided with a conical spouted bed reactor. The inert gas used is nitrogen and the temperature has been varied from 425 to 610 °C. Discontinuous runs have been carried out for obtaining the kinetic data, and the product stream has been analysed on-line at different reaction times, thereby monitoring the evolution with time of mass fraction of the different components. The kinetic model gives reasonable predictions for lump yields.