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Show Figure 3 Burner Concept Unstaged SR=1 .16 02 (%vol wet) 20 18 16 1. 12 10 .• 8 O2 Concentrations on Bumer and OFA Mid-planes Predicted Oxygen Concentrations in the SBS for Staged and Unstaged Combustion Subsystem Scale Experimental Testing A 100 MBtulhr advanced 10w-NOx burner was fabricated for subsystem testing based on results from pilot-scale testing and numerical modeling. B&W's Clean Environment Development Facility was utilized for subsystem testing. The advantage of using the CEDF for subsystem scale testing was in the ability to test a near full-size burner in an environment which closely simulates a utility boiler. The CEDF is designed for a heat input of 100 MBtu/hr, and integrates combustion and postcombustion testing capabilities to facilitate the development for the next generation of power generation equipment. A wide range of fuels including pulverized coal, fuel oil, and natural gas can be fired. The furnace (Figure 4) is designed for testing a single 100 MBtulhr burner, or multiple wall-fired burner configurations. It has been carefully designed to yield combustion zone temperatures, flow patterns, and residence times representative of commercial boilers. In order to provide maximum flexibility and control, separate fans and air heaters are used for supplying the pulverizer, primary (coal conveying) air, and secondary (windbox) air. The use of an indirect pulverized coal feed system in conjunction with the separate air supplies decouples pulverizer and burner operation, and permits operation over a wide range of coal types, air-to-fuel ratios, fuel moisture contents, and coal particle size distributions. Boiler convection pass and air heater simulators maintain representative conditions through the entire boiler system to facilitate studies of air toxics capture in back -end flue gas clean-up devices. Representative gas phase time-temperature profiles and surface metal temperatures are Page -7 |