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Show 600 500 400 300 • 200 100 O EER MT D Riley Stoker CBTF A ODDosed Fired 360 MW y Single Wall Fired 40U MW 100 200 300 Basket Area Heat Release, KBtu/Hr - Ft2 Figure 5. Unstaged N0X Emission Scaling Criteria for CCV Burners in Wall-fired Boilers DIRECTIONAL FLAME BURNER Riley Stoker's Directional Flame burner, shown in Figure 6, is an axial flow burner normally used in the Turbo furnace. In the Turbo furnace the burners are mounted in an opposed downward tilt configuration. The Directional Flame burner consists of two rectangular coal nozzles with secondary air above and below the nozzles. This burner is equipped with converging coal spreaders which direct the coal toward the burner centerline. Mixing of the secondary and primary streams is controlled by directional vanes in the secondary air throat (5,6). In our single burner test configuration staged combustion was achieved by introducing the staged air through ports downstream of the burner, on the side walls of the test furnace. These ports were designed to simulate the use of overfire air in a field installation. The downstream air ports were arranged as opposing jets at 17, 23, and 30 feet downstream of the burner wall. 8 |