Evaluation on isothermal pyrolysis characteristics of typical technical solid wastes

摘要

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 degrees C and 550 degrees 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 degrees C to 550 degrees 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.