Is there interaction between forestry residue and crop residue in co-pyrolysis? Evidence from wood sawdust and peanut shell

Numerous studies have shown that co-pyrolysis of biomass with other materials (i.e., coal and municipal waste) can result in better overall performance. However, both forestry residue and crop residue are subclasses of biomass, and there are few studies on whether they interact with each other during co-pyrolysis. In this study, five mixture pellets of wood sawdust (WS) and peanut shell (PS) were prepared using five different mixing ratios (WS:PS = 10:0, 7:3, 5:5, 3:7, and 0:10). Co-pyrolysis experiments were conducted using a thermogravimetric analyzer and Fourier transform infrared spectroscopy. Compared with WS and PS alone, W3P7 (WS:PS = 3:7) increased the comprehensive pyrolysis index by 15.0-27.8%, 20.8-96.1%, and 17.9-88.0% at heating rates of 10, 20, and 30 K min(-1), respectively. In the pyrolysis of the five samples, the reaction mechanism during the rapid mass loss period was most likely random nucleation and subsequent growth. Combined with the results of the thermodynamic and kinetic analyses, W3P7 had the best pyrolysis performance. This study can deepen the understanding of the thermochemical reaction of mixtures composed of forestry residue and crop residue, which will be helpful for further modeling and simulation of co-pyrolysis of PS and WS in the future.