METHOD FOR REMOVING CO AND NOX IN EXHAUST GAS OF COMBINED SYSTEM

摘要

PURPOSE:To efficiently remove CO and NOx, by providing not only a first bed of a Cu-mordenite catalyst to an exhaust gas flow passage reaching 400 deg.C or more but also a second bed of the Cu-mordenite catalyst to an exhaust gas flow passage of below 400 deg.C. CONSTITUTION:Exhaust gas containing CO and NOx exhausted from a gas turbine 1 flows in a first catalyst bed 9a at about 530 deg.C and CO in the exhaust gas is reacted with O2 in the first catalyst bed 9a to be converted to CO2. Said exhaust gas is mixed with NH3 injected from an NH3 injection apparatus 6 at the point of time when passed through a superheater 2 and an evaporator 3 to be introduced into a second catalyst bed 9b. Because the temp. of the exhaust gas reaches about 350 deg.C herein, no N2O is formed as a byproduct and NOx is reduced by NH3 to form N2 and H2O.