Abstract |
The report gives results of a field evaluation of the Distributed Mixing Burner (DMB) on a 98 kg/hr (215,000 lb/hr) steaming capacity, four-burner, front-wall-fired boiler. Following DMB installation, the boiler was operated and tested with the new burners for 17 months. Under routine operation, the DMBs reduced NOx emissions by about 50 percent--from the baseline condition of about 0.96 to about 0.46 lb/million Btu (418 to 200 ng/J). Under carefully controlled, optimized conditions, NOx emissions were further reduced about another 20 percent--to about 0.3 lb/million Btu (131 ng/J). The DMB is a low-NOx pulverized-coal burner for wall-fired boiler applications. It operates under reducing conditions in the primary flame zone to minimize NOx emissions while an overall oxidizing environment is maintained in the furnace to minimize slagging and corrosion. |