Fast pyrolysis of coals under N2 and CO2 atmospheres: Experiments and modeling

• Published in: Journal of thermal analysis and calorimetry 2018-09, Vol.133 (3), p.1535-1547
• Main Authors: Zellagui, Sami, Schönnenbeck, Cornelius, Zouaoui, Nabila, Brilhac, Jean-François, Authier, Olivier, Thunin, Emmanuel, Porcheron, Lynda
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Chemistry; Chemistry and Materials Science; Inorganic Chemistry; Measurement Science and Instrumentation; Physical Chemistry; Polymer Sciences
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-018-7218-7

Oxyfuel combustion represents one way for cleaner energy production using coal as combustible. The comparison between the oxycombustion and the conventional air combustion process starts with the investigation of the pyrolysis step. The aim of this contribution is to evaluate the impact of N 2 (for conventional air combustion) and CO 2 (for oxy-fuel combustion) atmospheres during pyrolysis of three different coals. The experiments are conducted in a drop tube furnace over a wide temperature range 800–1400 °C and for residence time ranging between 0.2 and 1.2 s. Coal devolatilized in N 2 and CO 2 atmospheres at low temperatures ( 1200 °C) and longer residence times (> 0.5 s), the char-CO 2 reaction is clearly observed, whose intensity depends on the nature of the coal. Furthermore, the volatile yields are simulated using Kobayashi’s scheme and kinetic parameters are predicted for each coal. The char gasification under CO 2 is also accounted for by the model.