Abstract |
The report gives results of tests on a 100 million Btu/hr (29 MWt) experimental furnace to explore methods for achieving effective SO2 removal in a coal-fired utility boiler using calcium-based sorbents, through appropriate selection of injection location and injector design/operating parameters. Methods were also tested to reduce NOx emissions from the coal burners without external air ports (i.e., with internal fuel/air staging). Sorbent jet testing showed that, through cold modelling, injection locations and velocities could be selected which avoided recirculation of the sorbent into the burner zone (hence dead-burning). At the best conditions, SO2 removals at Ca/S = 2 were 30-40% with finely ground limestone, 45-50% with dolomite, and 60% with pressure-hydrated dolomitic lime. Limited testing of burner modifications to achieve internal staging resulted in about a 35% reduction in NOx, through use of coal splitters. |