METHOD AND DEVICE FOR ELIMINATING NOX AND N2O

摘要

The invention relates to a method for removing N2O and NOx from exhaust gases. The DeNOx stage is operated downstream of the DeN2O stage at inlet temperatures of T 2O stage contains water and has a selected N2O/NOx ratio. The operating parameters of temperature, pressure, and spatial velocity of the DeN2O stage are selected in such a way that an N2O decomposition of 80 to 98% results. Under said conditions, the downstream DeNOx stage can be operated under optimal conditions. The method can be performed in a device that comprises the following elements: A) a device (2) for adjusting the water content of the gas (1) containing NOx and N2O, B) a DeN2O stage (3) for reducing the N2O content of the gas flow, containing a zeolite catalyst loaded with iron, C) a cooling device (4) for cooling the gas flow (5) leaving the DeN2O stage, D) a DeNOx stage (6) containing an SCR catalyst for reducing the NOx content of the gas flow, and E) a supply line (7) for introducing reductant for NOx into the gas flow (5) leaving the DeN2O stage.