CATALYTIC FUEL COMBUSTION - A WAY OF REDUCING EMISSION OF NITROGEN-OXIDES

The present survey has shown that catalytic combustion can be successfully applied to various domestic and industrial fuel-burning devices for improving combustion efficiency and thermal NOxcontrol. The problem of fuel NOxcontrol has not been as yet reliably solved for installations using platinum catalysts and operated at high temperatures and mass throughputs. The investigation of kinetics of oxidation of nitrogen-containing compounds on solid catalysts has shown that the fuel NOxyield can be decreased by the use of oxide catalysts rather than platinum ones, by low excess air operation, and by decreasing the temperature. A low-temperature operation is usually accompanied by the decrease of the power and thermal efficiency of a device. The combustion of fuels in a fluidized catalyst bed in catalytic heat generators makes it possible to conduct technological processes at high fuel loads on a catalyst and at rather low temperatures in the combustion zone (770-1070K) owing to the combination of heat evolution and heat removal in the same catalyst bed. It is important to note that low NOxconcentrations are ensured by the method of combustion itself, and by the choice of catalyst. © 1990, Taylor & Francis Group, LLC. All rights reserved.