PURPOSE: To efficiently execute the denitrification of an NOx containing gas such as a waste gas by allowing the NOx containing gas to catalytically react with a denitrification agent obtained by carrying a catalystic metal on a zeolite in the coexistence of propionic acid and/or oxalic acid.
CONSTITUTION: NOx is removed by allowing the NOx containing gas to catalytically react with the denitrification agent obtained by carrying the catalystic metal on the zeolite in the coexistence of propionic acid and/or oxalic acid. The measurement of the denitrification ratio is executed by a denitrification device. A waste gas is introduced into a reaction vessel 3 after particulates are removed by a honeycomb 2 for removing particulate material and a reducing agent is sprayed through a reducing agent spraying opening 8. The flow rate is controlled by a flow control valve 7. In this case, the reaction vessel 3 is heated by a heater 6 and the excess portion of a standard gas is introduced into an NOx analyzer 5. In this way, NOx concn. before nitrification is measured.
ASANO YOSHIHIKO
KURAMOTO MASAMICHI
Next Patent: DENITRIFICATION METHOD