Experimental evaluation of the pyrolysis of plastic residues and waste tires

The paper presents the design of the experimental apparatus developed in order to analyse the performance of a prototype of a pyrolysis system for the exploitation of the plastic residues of industrial processes and the end-of-life tires. The small-scale pilot prototype is specifically designed for carrying out an experimental campaign aimed at determining the influence of different plastic types on the yield and on the quality of the liquid oil, gas and char obtained in the pyrolysis process. The study investigates the effect of different mixtures of various plastic products mainly made of polyethylene, styrene butadiene rubber, nylon, and natural rubber. The prototype is equipped with a control system able to monitor the main operating parameters of the process, such as the pyrogas pressure and temperature as well as the temperature inside the reactor where the pyrolysis takes place. The monitored variables are employed for deriving correlations among the operating conditions and the yield of the pyrolysis process. Moreover, SPME-GC/MS analysis were performed on different gas samples to estimate the main compounds that are contained in the syngas in comparison to the different plastic wastes analysed. Thus, the emissions of the small-scale prototype are evaluated. The results obtained by means of the experimental campaign performed on the test rig were used to carry out the economic assessment of an integrated pyrolysis system for the exploitation of the plastic residues from an industrial plant.