Investigation of co-combustion behavior of Robinia pseudoacacia char with anthracite in oxygen-enriched condition

• Published in: Journal of thermal analysis and calorimetry Vol. 147; no. 22; pp. 12883 - 12895
• Main Authors: Yang, Guang, Liu, Yiran, Gao, Lijuan, Su, Yingjie
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.11.2022; Springer; Springer Nature B.V
• Subjects: Activation energy; Alternative energy sources; Analysis; Analytical Chemistry; Anthracite; Blending effects; Burning time; Chemistry; Chemistry and Materials Science; Combustion; Compensation; Flammability; Ignition temperature; Inorganic Chemistry; Investigations; Measurement Science and Instrumentation; Mixtures; Oxygen enrichment; Physical Chemistry; Polymer Sciences; Thermogravimetry; Combustion characteristic parameters; a char; Thermogravimetric analysis; Kinetic compensation effect; Interaction effect
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-022-11463-9

Co-combustion of biochar with coal has the high potential to increase renewables in the carbon-intensive and energy-intensive industries. In this study, the combustion behavior of anthracite (AN), Robinia pseudoacacia char (RPC) and their blends were studied by thermogravimetry analysis. The ignition temperature (647 K) of RPC was lower than AN (723 K), lower ignition temperature and a longer burning time were observed by adding RPC. Simultaneously, the flammability index ( C ) and comprehensive combustion characteristic index ( S ) of RPC and AN were analogous, such as C RPC (7.506 × 10 −5 ), C AN (6.244 × 10 −5 ), S RPC (11.525 × 10 −7 ) and S AN (11.143 × 10 −7 ). At a same time, the interaction effect were observed during the co-combustion process, and the positive interaction effect was found to be strongest at 763 K with a blending ratio of 20RPC80AN. The kinetic methods of Coats–Redfern, MacCallum–Tanner, Freeman–Carroll, Madhusudanan–Krishan–Ninan, Flynn–Wall–Ozawa and Zavkovic were applied to calculate the kinetic parameters and the mechanism function models of co-combustion was determined by Malek method. The activation energy (102.91 kJ mol −1 ) of RPC was lower than AN (165.36 kJ mol −1 ), it has been found that the activation energy their blends was reduced by adding RPC. In addition, based on these six models, the rationality of kinetic results was verified by Kinetic Compensation Effect, indicating that the activation energy of the blends of different proportions has a good compensation relationship with the pre-exponential factor. Graphical abstract