Parkhurst & Wendel, L.L.P.
System for removing NOx from exhaust gases
An NOx removal system has a combustion apparatus for applying energy to a load based on a predetermined combustion control process, an NOx remover for reacting NOx emitted from the combustion apparatus with NH3 to produce N2 and H2O, an NH3 and/or urea introducing apparatus connected upstream of the NOx remover, for introducing NH3 and/or urea into a gas passage extending from the combustion apparatus to the NOx remover, and sensor, which is also sensitive connected downstream of the NOx remover, for generating a detected signal based on NH3 and NOx contained in a gas discharged from the NOx remover. A controller controls a rate at which NH3 and/or urea is introduced into the gas passage by the NH3 and/or urea introducing apparatus while repeatedly increasing and reducing the rate, in response to the detected signal generated by the NOx sensor. The NOx removal system, which employs NH3 and/or urea as a reducing agent, is capable of accurately controlling the rate at which NH3 and/or urea is introduced into the gas passage through a simple arrangement, and minimizing the discharge of NH3 and NOx.
NGK Insulators, Ltd.
Y Y B B B F B B F
Y02T Y10S B01D B01D B01D F01N B01D B01D F01N
additional additional additional inventional inventional additional additional inventional inventional
Nobuhide Hiroshi
Kato Kurachi