Combustion behaviors of Pteris vittata using thermogravimetric, kinetic, emission and optimization analyses

This study aims to assess the combustion efficiency and emissions of both aboveground (PA) and belowground (PB) biomass parts of Pteris vittata. Their combustion process consisted of three major stages, with devolatilization as the main stage of mass loss by 59.06% between 182 and 382 degrees C for PA, and by 58.24% between 182 and 375 degrees C for PB. The primary emissions were related to the carbonaceous (90.50% for PA; 90.80% for PB) and N-containing species (6.95% for PA; 6.56% for PB). 172.44% SO2, 137.49% NO2, and 124.48% CO emissions were released more from the PB than PA combustion. Air pollutants were generated between 70 and 500 degrees C from PA and 60 and 700 degrees C from PB, with the PB combustion requiring more pollution controls at a higher temperature. The joint optimizations of derivative thermogravimetry, differential scanning calorimetry, remaining mass, and conversion degree indicated 999.2 and 514.6 degrees C for combustion temperature, 193.6 and 97.1 min for combustion duration, and 40 degrees C/min for heating rate as the optimum operational schemes for the cleanest production for the PB and PA combustions, respectively. Average activation energy was described using four iso-conversion and integral masterplots methods. The hemicelluloses combustion for PA and PB were best described by the diffusion mechanisms, while the cellulose and lignin + char combustions corresponded to the reaction order mechanisms. Our results contribute to developing the new strategies of cleaner production with the P. vittata combustion. (C) 2019 Elsevier Ltd. All rights reserved.