Investigation on thermal behavior and sulfur release characteristics from rice husk and bituminous coal co-firing under O2/CO2 atmosphere

The synergistic interaction of rice husk (RH), Huaibei bituminous coal (HB coal), and their blends was investigated under O-2/CO2 combustion condition by thermogravimetric analysis. The RH was blended with HB coal in the range of 20-40wt% to investigate the co-combustion profile. Meanwhile, a horizontal tube furnace was used to study the sulfur release characteristics of blended fuels under O-2/CO2 atmosphere. Results showed that the synergistic interaction between RH and HB coal improved the char catalytic effect and alkali metals melt-induced effect on the decomposition of HB coal. Burnout temperature (T-b) of blended fuels decreases significantly with an increase of RH ratio and oxygen ratio, ignition temperature (T-i) decreases with increases of RH ratio, while there is a minor decrease in T-i at higher oxygen ratio. Combustion characteristic indexes of blended fuel increase with an increase of RH ratio and oxygen ratio. The SO2 peak values decrease with increases of RH ratio, and increase with an increase of oxygen ratio and temperature. However, the mean SO2 emissions and fuel-S conversions show the inverse trend. (c) 2015 Curtin University of Technology and John Wiley & Sons, Ltd.