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Show For fuel rich regions near the primary reaction zone, the prompt NOx reactions in vol vi ng CH and CH2 are the most likely route. This is especially true for cases in which e xtreme back mi xing occurs, such as in industrial burners." KlNBTlC NOx OORMATION R:>R ~ PROMPT, AND THIRD BODY MECHANISMS 1.2 1.0 ........... ~ .............................................................................................. . ............... 'o~...,~ ..... .. ..............................................0. ............................... . ± \ :::::::::::::::::::::::::::::\)(=s::: ,::::::::~::-:::::::::::::::::::: ! . . ~ .6 .1 0..0 -0.2 0.5 0..6 0..1 o..J 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.3 PREMIX STOICHIOMETRY . TIIBMAL + PROMPT "* 3IID Ba>Y 0 TOrAL Figure 2 Of particular interest was a sensitivity analysis was conducted by Glarborg, Miller and Kee in 1986 of experimental data collected by other researchers. 5 The more important of the 213 react ions studied are plotted in figure 2. The conclusion is that prompt NOx formation is dominant in rich combustion. Lean flames or excessively cool temperature reduces prompt NOx. However, in diffusion flame industrial burners, substoichiometric fuel / air interfaces exist even when overall stoichiometric conditions are lean. Obtaining lean flames and minimizing substoichiometric conditions is difficult, but is the design goal of a new low NOx burner. Burner design concept. To build a commercially practical industrial ultra-low NOx burner, a number of problems must be overcome: Page 3 |