Kinetic Characteristics of the Oxidation of Non-Food Municipal Solid Waste

Abstract

The kinetic characteristics of the oxidation of non-food municipal MSW (MSW) were studied. Energetically valuable components of non-food MSW (sawdust, plastics, cardboard, textiles, leather, and rubber) were used as test samples. The elemental composition and technical characteristics of the test samples were determined using an elemental analyzer and standard procedures. The thermal conversion of non-food MSW was carried out using thermogravimetric analysis in the oxidation mode at a heating rate of 10 K/min in a temperature range of 25–800°C at atmospheric pressure. According to thermal analysis data (DTG curves), the process stages of the oxidation of non-food MSW, which correspond to the mono- or bimodal evolution of volatile compounds and the oxidation of the resulting carbon residue, were determined. The qualitative analysis of the gas-phase products of non-food MSW oxidation was performed by mass spectrometry, and the results were compared with the elemental composition and technical characteristics of the test samples. The activation energies of the stages of non-food MSW oxidation were calculated using the Coats–Redfern method. The maximum value of Ea (114.7 kJ/mol) was observed in a plastic sample, the decomposition of which tentatively proceeded in a single stage.