Thermal behavior, kinetics and synergistic effect of co-pyrolysis of moso bamboo with bituminous coal using thermogravimetric analysis and artificial neural network

The thermal decomposition behavior, kinetics and interactions during co-pyrolysis of moso bamboo and bituminous coal were investigated by thermogravimetric analysis and artificial neural networks. Compared with bituminous coal, moso bamboo showed a lower initial pyrolysis temperature, a lower devolatilization stage and a higher decomposition rate. Co-pyrolysis involved devolatilization of moso bamboo at low temperature and devolatilization of bituminous coal at high temperature. With the blending of moso bamboo, the initial pyrolysis temperature showed a decrease of approximately 100?C. The decomposition rate increased from 2.07 to 8.24 %/min, showing a larger devolatilization index and strengthened devolatilization reactivity. A higher heating rate accelerated the decomposition rate and strengthened char pyrolysis. As the heating rate increased, the devolatilization index could be doubled. The overall activation energy of co-pyrolysis was lower than that of individual coal pyrolysis, first decreasing and then increasing with moso bamboo blending. The minimum overall activation energy (~54 kJ/mol) for co-pyrolysis was found with a moso bamboo blending ratio of 25-4 %. Meanwhile, the activation energy proportion for moso bamboo devolatilization gradually increased with moso bamboo blending. Significant synergy was found with the moso bamboo blending ratio of 40-60 %, manifesting as a shift of the weight loss peak to higher temperature and an increase in the weight loss rate and degree. Trained artificial neural network models were built and optimized using the transfer function and hidden layers to predict the co-pyrolysis thermogravimetric profiles.