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Show Abstract Development and Testing of the MIT -RSFC Low-NOx Coal Combustor for The B&W LEBS Program J. M. Beer, L. E. Barta, P. F. Lewis, V. Wood O. Akinyemi, J. Haynes, J. Jimenez and R. Manurung Combustion Research Facility Massachusetts Institute of Technology Cambridge, MA 02139 L. W. Rodgers Babcock & Wilcox Alliance, OH MIT as a partner with Babcock & Wilcox, a McDermott Company in the USDOE sponsored Low Emission Boiler System (LEBS) program has performed an experimental analytical and experimental effort to refine and define the operational characteristics of the MlT Radially Stratified Flame Core (RSFC)Burner for the combustion of pulverized coal. The RSFC has been previously developed to a very promising state for natural gasl and to a lesser extent for heavy fuel oil2 firing. In this effort the burner was operated at a nominal firing rate of 5 mm BtuIhr on lllinois #6 coal. NOx, CO and unburned carbon emission data have been collected and analyzed for a wide range of conditions. Burner performance has been evaluated as a function of burner settings, firing rate, air equivalence ratio, air preheat, transport air to coal ratio and excess air. For selected conditions, detailed in flame measurements of gas composi~on, temperature, ~d velocity as well as solids concentration and composition have been performed. These data can be used for detailed analysis and modeling studies. The performance of the burner was found to be superior to the expected results. The burner was extremely stable, and relatively insensitive to operating conditions. NOx levels below 100 ppm with carbon burnout greater than 99% were achieved. Introduction The purpose of this report is to describe work performed for the U.S. DOE under subcontract to Babcock & Wilcox on the development of a Low NOx pulverized coal burner « 0.15 lb/mm Btu fired) for the DOE Low Emission Boiler System (LEBS) program. In this report we will describe data and analysis obtained at the l\.1IT Energy Laboratory's Combustion Research Facility (CRF) on the development of the Low NOx pulverized coal burner. For the purposes of this development an existing Low Nox research burner called the RSFC (Figure 1) and described in patent application No. 771,739 was used. A unique feature of the RSFC burner is its capability of reducing air-fuel mixing in the near field while promoting it further downstream of the burner. Radial density stratification brought about by the combination of rotating burner air flow and the density |