Advanced Diagnostic Evaluation of an Ultra-Low NOx Industrial Gas Burner

Energy and Environmental Research Corporation (EER), Selas Corporation of America and the Gas Research Institute (GRI) have teamed to demonstrate the utility of advanced laser diagnostics and conventional diagnostics in studying an ultra-low NOx industrial gas burner. The test platform is the GRIlSandia Burner Engineering Research Laboratory (BERL) located at Sandia National Laboratories in Livermore, CA. This laboratory is used for the application of advanced diagnostic methods to study pollution formation and characterize burner performance. Tests conducted over an eight week schedule in the BERL parametrically evaluated a modified Selas K988 burner (U.S. Patent No. 5,271,729). The tests were conducted under regimes of operation where NOx emissions as low as 7 ppm (dry, 3% 02), or 0.01 lb/MMBtu, were achieved at full load with over ten percent excess air. Measurements identified regions of high CH radical concentrations, characterized the flame structure, the staged jet mixing pattern, the in-flame gas species concentrations and the inflame gas temperatures. Some of the advanced diagnostics employed during this burner study included laser doppler velocimetry to study near burner gas flow velocity and direction, Mie scattering to capture images of the burner's jet mixing structure and chemiluminescence to identify high concentrations of CH radicals in the flame zone. Results from the advanced diagnostic techniques are helpful in identifying potential regions of NOx formation and providing information suited towards refining the burner design for further NOx reductions under general furnace (rather than ideal laboratory) conditions.