Abstract: A diesel powered vehicle is provided with an SCR system which uses an external reducing reagent to convert NOx emissions in a manner which accounts for the effects of NOx transient emissions on the reducing catalyst. Actual NOx emissions produced by the engine are filtered using a variable NOx time constant in turn correlated to the reductant/NOx storage capacity of the reducing catalyst at its current temperature to account for changes in the SCR system attributed to NOx transient emissions. Catalyst temperature is filtered using a variable catalyst time constant corresponding to current space velocity of the exhaust gas to account for changes in the catalyst temperature attributed to NOx transient emissions. The reductant is metered on the basis of the filtered, corrected NOx concentration applied at a NSR ratio based, in turn, on the filtered, corrected reducing catalyst temperature.

Abstract: A diesel powered vehicle is provided with an SCR system which uses an external reducing reagent to convert NOx emissions in a manner which accounts for the effects of NOx transient emissions on the reducing catalyst. Actual NOx emissions produced by the engine are filtered using a variable NOx time constant in turn correlated to the reductant/NOx storage capacity of the reducing catalyst at its current temperature to account for changes in the SCR system attributed to NOx transient emissions. Catalyst temperature is filtered using a variable catalyst time constant corresponding to current space velocity of the exhaust gas to account for changes in the catalyst temperature attributed to NOx transient emissions. The reductant is metered on the basis of the filtered, corrected NOx concentration applied at a NSR ratio based, in turn, on the filtered, corrected reducing catalyst temperature.

Abstract: A diesel powered vehicle is provided with an SCR system which uses an external reducing reagent to convert NOx emissions in a manner which accounts for the effects of NOx transient emissions on the reducing catalyst. Actual NOx emissions produced by the engine are filtered using a variable NOx time constant in turn correlated to the reductant/NOx storage capacity of the reducing catalyst at its current temperature to account for changes in the SCR system attributed to NOx transient emissions. Catalyst temperature is filtered using a variable catalyst time constant corresponding to current space velocity of the exhaust gas to account for changes in the catalyst temperature attributed to NOx transient emissions. The reductant is metered on the basis of the filtered, corrected NOx concentration applied at a NSR ratio based, in turn, on the filtered, corrected reducing catalyst temperature.

Abstract: A diesel powered vehicle is provided with an SCR system which uses an external reducing reagent to convert NOx emissions in a manner which accounts for the effects of NOx transient emissions on the reducing catalyst. Actual NOx emissions produced by the engine are filtered using a variable NOx time constant in turn correlated to the reductant/NOx storage capacity of the reducing catalyst at its current temperature to account for changes in the SCR system attributed to NOx transient emissions. Catalyst temperature is filtered using a variable catalyst time constant corresponding to current space velocity of the exhaust gas to account for changes in the catalyst temperature attributed to NOx transient emissions. The reductant is metered on the basis of the filtered, corrected NOx concentration applied at a NSR ratio based, in turn, on the filtered, corrected reducing catalyst temperature.

Abstract: A diesel powered vehicle is provided with an SCR system which uses an external reducing reagent to convert NOx emissions in a manner which accounts for the effects of NOx transient emissions on the reducing catalyst. Actual NOx emissions produced by the engine are filtered using a variable NOx time constant in turn correlated to the reductant/NOx storage capacity of the reducing catalyst at its current temperature to account for changes in the SCR system attributed to NOx transient emissions. Catalyst temperature is filtered using a variable catalyst time constant corresponding to current space velocity of the exhaust gas to account for changes in the catalyst temperature attributed to NOx transient emissions. The reductant is metered on the basis of the filtered, corrected NOx concentration applied at a NSR ratio based, in turn, on the filtered, corrected reducing catalyst temperature.

Abstract: A diesel engine aftertreatment exhaust system uses catalyzed soot filters for particulate matter reduction and urea SCR catalysts for NOx reduction on diesel engines in a combined system to lower particulate matter and NOx at the same time. With this integral emission control system, diesel engines are able to meet ultra low emission standards.

Abstract: The present invention relates to a method of removing a coating, such as a spent catalyst coating, from a carrier such as a metal plate or a honeycomb carrier. The metal plates have a surface which has the catalyst coating. The honeycomb is of the type having a plurality of channels defined by honeycomb walls, the honeycomb walls the having a coating thereon. The method comprises directing a fluid stream which can comprise a cleaning liquid at the coated plate surface or into the honeycomb channels with sufficient force to loosen and remove at least some of the coating from the carrier surface. The carrier can then be separated from the liquid and dried. Where additional coating is to be removed, a stream of gas is directed at the carrier surface with sufficient force to loosen and remove at least some of the coating. The cleaned carrier can then be recoated. The present invention includes reclaimed and recoated articles.

Abstract: An external reductant for an SCR vehicular NO.sub.x emission control system is selectively injected to SCR catalysts which are only at catalytically active temperatures thereby avoiding reductant absorption in catalytically unactive catalysts and improving conversion response time.

Abstract: The present invention relates to a method of removing a coating, such as a spent catalyst coating, from a carrier such as a metal plate or a honeycomb carrier. The metal plates have a surface which has the catalyst coating. The honeycomb is of the type having a plurality of channels defined by honeycomb walls, the honeycomb walls the having a coating thereon. The method comprises directing a fluid stream which can comprise a cleaning liquid at the coated plate surface or into the honeycomb channels with sufficient force to loosen and remove at least some of the coating from the carrier surface. The carrier can then be separated from the liquid and dried. Where additional coating is to be removed, a stream of gas is directed at the carrier surface with sufficient force to loosen and remove at least some of the coating. The cleaned carrier can then be recoated. The present invention includes reclaimed and recoated articles.