Effect of O₂ concentration on combustion behavior and kinetics of coal gangue during oxy‐fuel combustion and oxy‐steam combustion

Abstract

In this work, the effect of O2 concentration on combustion behavior and kinetics of coal gangue during oxy‐fuel combustion and oxy‐steam combustion were studied by non‐isothermal thermogravimetric analysis technology. The results showed that the increase of O2 concentration could improve the combustion performance of coal gangue. The O2/CO2 atmosphere was unfavorable to the combustion of coal gangue compared with the O2/N2 atmosphere. Furthermore, the gasification reaction could accelerate overall carbon consumption in oxy‐steam combustion with 5% O2 concentration; and the presence of H2O could delay the ignition and accelerate burnout at this condition. Kinetic analysis showed that the combustion of coal gangue in O2/N2 and O2/CO2 atmosphere followed the first‐order kinetics under O2 concentrations studied; and the combustion in O2/H2O atmosphere followed the 0.5‐order kinetics at 5% and 10% O2 concentration, while it followed the first‐order kinetics at 21% O2 concentration.

Staged co‐gasification characteristics of pyrolyzed semi‐coke and antibiotic filter residue under oxy‐fuel condition

“…Nevertheless, the co-gasification technology of AFR with ultra-low volatile coal-based material is still immature and needs further specific exploration. On the other hand, oxy-fuel combustion technology, which has the potential to achieve zero or even negative carbon emissions, 6,7 is one of the most promising carbon capture and storage (CCS) technologies. 8,9 Less work has been performed on staged oxy-fuel co-gasification of powdery SC and AFR.…”