Analysis on combustion kinetics and emission characteristics of disposable paper cups

Abstract

Most disposable paper cups (DPCs) end up being incinerated like most household waste due to high costs and technical limitations in China. And this has raised concerns due to potential environmental and health hazards. A combination of thermogravimetric analysis, fourier-transform infrared spectroscopy and mass spectrometry (TG-FTIR-MS) was employed to analyze the combustion process and identify the emitted gases during DPCs burning in this study. The combustion kinetics were elucidated through the Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) methods. The physicochemical characterization revealed remarkably high volatile matter (94.51 wt%) and an impressively high heating value of pistachio shell (19.54 MJ/kg). Combustion experiments were conducted in air atmosphere, starting from 30 ℃ to 1000 ℃, at four different heating rates of 10, 20, and 40 K/min. The TG results showed that combustion process of the DPCs included four stages and more than 80% of weight loss occurred at active combustion with temperature of 210–520 ℃, whose reaction mechanism can be described by the P5 model. The activation energies were calculated as 219.79 and 218.56 kJ/mol, respectively. TG-FTIR analysis revealed that CO2, H2O, CO, C = O, C-O and C-H functional group as the main combustion gas products. The relative concentration of the main volatile products was in the order of CO2 > H2O > C = O > aromatic compounds > C-O > CO > C-H according to TG-MS. This study provided a comprehensive understanding of the combustion behavior of DPCs and highlighted the importance of proper waste management to mitigate the environmental impact of DPCs.