Pyrolysis of Paper and Cardboard in Inert and Oxidative Environments

Data on the thermal destruction behavior of paper and cardboard under controlled conditions are presented. The decomposition behavior was determined using a thermogravimetric analyzer and differential scanning calorimetry. Tests were carried out on paper, cardboard, and cellulose at two different heating rates of 10 and 50°C/min, and surrounding gas environments of argon (for pyrolysis), air, or oxygen (for oxidative pyrolysis). The temperature range for the thermal decomposition behavior was varied from 25 to 1000°C to investigate the entire decomposition spectra. Global decomposition data show that the maximum decomposition shifts to higher temperatures at higher heating rates as a result of the competing effects of heat and mass transfer, product diffusion, and reaction kinetics. The Arrhenius parameters for thermal decomposition were determined using a first-order decomposition reaction of the form: dm = —k x m x df. Results showed that the activation energy, heat of pyrolysis, and char yield are strongly dependent on the heating rate. An increase in heating rate results in a decrease in activation energy and an increased char yield. The heating rate dependence of the kinetic parameters is discussed. The decomposition behavior of the materials examined is endothermic, whereas the overall process is exothermic because of the presence of oxygen in the material. In general, parameters such as heat transfer, mass diffusion, product evolution, heating rate, temperature, and the surrounding environment control the decomposition process. The results show significant variation in the thermal decomposition behavior of the samples. Furthermore, marked variation have been found from sample-to-sample. These variations suggest challenges associated with the exact determination of thermal decomposition characteristics of real wastes. Despite these variations, data presented in this paper are useful for design guidelines for solid waste thermal destruction systems.