Evaluation on isothermal pyrolysis characteristics of typical technical solid wastes

Abstract

Isothermal pyrolysis characteristics of typical technical solid wastes (polyethylene, paper towel and textiles, and their mixture with a blending ratio of 4:1:1) were carried out in a fixed bed between 475 °C and 550 °C. The influence of the temperature on the pyrolysis index, kinetic parameters and products of the samples was addressed. The interaction between the three individuals during their co-pyrolysis was identified. As the temperature was from 475 °C to 550 °C, the pyrolysis index of the polyethylene increased by about 78 times, while that for paper towel and textiles only increased by about 1 and 6 times, respectively. Solid residues from the mixture pyrolysis were about 11.6 % wt. More alkanes and alkenes were in liquid products of the mixture. The shrinking core model would represent well the mixture pyrolysis. The pre-exponential factor of polyethylene was much higher than other two individuals. There was a significant synergistic effect detected for mixture during the co-pyrolysis. The pyrolysis of mixture was dominated by a third order reaction mechanism. This study can provide basic data for the thermal treatment of solid waste in nuclear power plants.