PROCESS FOR ELIMINATING NOX AND N2O FROM THE RESIDUAL GAS FROM NITRIC ACID PRODUCTION

摘要

A method for the removal of NOX and N2O from the residual gas in nitric acid production is disclosed. The method comprises passing the residual gases leaving the absorption tower, through a two-stage combination before introduction into the residual gas turbine. In the first stage the NOx conte nt of the gas is reduced and in the second stage the N2O content is reduced. Th e NOx/N2O ratio, before entry into the second stage, is in the range from 0,00 1 to 0,5 and said gas is brought into contact with a catalyst in the second stage. Said catalyst comprises essentially one or several iron-loaded zeolit es.