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Show As can be seen from Figure 11, LNI results in a dramatic reduction in furnace N O x emissions, from 0.35 lb/MMBtu for a conventional burner firing into a 2300 F furnace with 900 F preheat temperature, 0.36 to 0.08 lb/MMBtu for the LNI burner firing at the same conditions. 4821-10-A, N O x emissions vs. temperature 0.500 Figure 11 o Regenerative Burners The North American Mfg. Co. TwinBed™ II regenerative burner is characterized by air preheat temperature capability approaching to within 200 degrees of furnace temperature. Pre-LNI installations firing natural gas with furnace temperatures in the 2200 to 2300 F range could result in N O x emissions levels of well over 1.2 lb/MMBtu as a result of the high air preheat level. The application of LNI to the TwinBed™ II burner provides N O x emission levels less than 0.1 lb/MMBtu at the same conditions. Identical parameters to those for ambient and preheated air burners were investigated in the development process for the gas fired LNI TwinBed™ II. Figures 12 and 13 indicate some of the test results. Recent regenerative burner development has focused on the application of the LNI technique to #2 and #6 fuel oils. A steam or compressed atomizer is used as a remotely located fuel injector for introduction of a stream of atomized fuel into the furnace. J 11 |