Experiments on lignite combustion in a circulating fluidized-bed reactor

In this study, a circulating fluidized bed (CFB) (0.15 m i.d. and 5.4 m high) was used to investigate the combustion characteristics, including riser temperature, major pollutant emissions (CO, SO2 and NO) and combustion efficiency, of Thai lignite. The combustion experiments were carried out at different excess air ratios (?0 = 0.97-1.50). The experimental results from combustion tests demonstrate that either or both the resulted change in the riser temperature in the CFB riser and the O2 availability for combustion affected the combustion efficiency (Ec) and formation of CO, SO2 and NO. The combustion efficiency varies between 96.0-97.4% depending on the excess air ratio.