PURPOSE: To make it possible to take out the required amt. of ammonia with good responsiveness in correspondence to a fluctuation in NOx concn. without allowing scale to be formed.
CONSTITUTION: The waste gases from a waste gas generating source 20 are subjected to denitrification in a denitrification reactor 23 and are thereafter discharged from a chimney 22 via a waste heat recovering boiler 21. The denitrification in the denitrification reactor 23 is effected by injecting NH3 from an evaporator 29 from a nozzle 25 into the denitrification reactor 23. The denitrification reactor 23 is provided with a NOx monitor 37 on the downstream side thereof to monitor the increase or decrease of the NOx quantity in the waste gases. The rate at which the aq. urea soln. 27 in a tank 26 is supplied to the evaporator 29 is increased and the amt. of the NH3 to be injected into the denitrification reactor 23 is increased when the NOx quantity increases. The rate at which the aq. urea soln. 27 is supplied to the evaporator 29 is so controlled as to be decreased and the amt. of the NH3 to be injected into the denitrification reactor 23 to be decreased when the NOx quantity decreases.
| JP3334022 | CONTAMINATED AIR PURIFIER |
| JP5628051 | Solvent recovery system |
| WO/1998/007497 | SPARK-IGNITED INTERNAL COMBUSTION ENGINE WITH AN NOx-ADSORBER |
WATANABE KO
KATO YASUYOSHI
IMADA NAOMI
