REDUCTION OF NITROGEN OXIDES EFFLUENTS WITHIN AN OPEN FLAME BY INPUT THE WATER VAPOUR INTO COMBUSTION AIR FLOW

Abstract

The state-of-the art the problem concerning reduction the NOx formation by humidification the combustion air is briefly consideredan, alized and discussed. The proper technologies of combustion the wet inflammable mixtures are considered for the cases of using the water vapour pump (WVP), Maisotsenko cycle (M-cycle) and suitable facilities along with the cases of operation the combined systems with heat recovery due transfer the water vapour energy to working medium (combustion products). Both environmental and power advantages of the systems of «wet combustion» have been demonstrated accordingly data collected in some earlier researches. The results of experimental researches of burning process under conditions of input the water vapour into the gas–air mixture to be supplied for combustion are presented in the paper in frame of consideration the results of own authors’ tests. Given information concerning the investigation of environmental consequences of impact the water vapour within the inflammable mixture on nitrogen oxides NOx value in combustion products ([NOx] concentration) has been generalized. The techniques of experimental researches, the design of firing rig and instrumentation, used in the tests have been described. The distinction of ignition the natural gas-air mixture and of stable flame maintenance for case of free vertical flame operation have been evaluated in dependence on inflammable mixture’s composition along with studying of impact a moisture content — H2O concentration in initial gas-air mixture. Comparative evaluations of NO value within an open flame in dependence on temperature and on composition of initial natural gas — air mixture (ratio «air : gas») have been carried out. An opportunity of two-times reduction of maximum NOmax concentration within a flame by initial gas-air mixture enrichment with water vapour has been proven. Bibl. 23, Fig.10, Tab.1.