Summary

This paper reports the emissions of SO2 from large coal under staged combustion without any additive. A stainless steel combustor, 2 m high and 0.3 x 0.3 m in cross section was used. Fluidizing air was supplied through a multihole distributor. An adjustable secondary air injector was used along the vertical axis of the combustor to introduce secondary air in the freeboard. From 0-40 % of total air was injected in the freeboard above the bed. The experiments were carried out at fluidizing velocities of 1-2 m s(-1), bed temperatures of 1103-1153 degrees K, 20-40 % excess air, and bed particle sizes of 665 mu m. Bed temperature and level of air staging had the most significant effect on SO2 emissions