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Show - The quality of atomization with liquid fuels which will affect rate of mixing. - The use of multistaged fuel injection to split up the flame and reduce the mean temperature. - The use of water or steam injection to reduce flame temperature. METHOD OF APPROXIMATING NOx In view of the 13 variables listed above, it is virtually impossible to find an accurate scientific method of calculating NOx levels in a given application. However, regulating authorities and potential customers often ask for data on expected NOx levels and their requests cannot be ignored. Without attempting to be definitive or cover all cases, the authors offer a simple, empirical method of approximating NOx which trys to use the "best state of the art" at this time. To be really useful, it needs a large number of results on different furnaces and burners. It is hoped and expected that these and other methods will be improved and become more sophisticated in the future, since reliable methods of estimating NOx are badly needed. NOx from air thermal fixation and NOx from fuel bound nitrogen organics must be estimated separately and in view of the multiplicity of known variables, as many as possible must be considered together by using empirically derived constants. Description of method: For estimating nitrogen fixation, read off the graph, fig. 2 for NOx at the required excess air, and if any combustion air preheat is involved, multiply by the factor from fig. 3, NOx multiplier vs. temperature. The result gives a good approximation for 13/6 |