Differential NH3 and NOX measurement using an exhaust gas sensor coupled with a micro SCR catalyst
AssigneeCummins Inc.
InventorsMert Geveci, Aleksey Yezerets
Life of this patent
Estimating the term…
Abstract
Systems and methods are disclosed that include an exhaust gas stream produced by an engine and an aftertreatment system including an SCR catalyst element receiving at least a portion of the exhaust gas stream. An exhaust outlet flow path has an inlet fluidly coupled to the exhaust gas stream at a position downstream of at least a portion of the SCR catalyst element that bypasses at least a portion of exhaust gas stream to provide for compositional measurement of the exhaust gas with a compositional sensor located downstream of a diagnostic catalyst positioned in the exhaust outlet flow path.
Claims30
A system, comprising:
- an internal combustion engine producing an exhaust gas stream as a byproduct of operation;
- an SCR catalyst element receiving at least a portion of the exhaust gas stream;
- an exhaust outlet flow path having an inlet fluidly coupled to the exhaust gas stream at a position downstream of the SCR catalyst element and upstream of an outlet of exhaust gas stream;
- a diagnostic SCR catalyst element receiving a portion of the exhaust gas stream through the exhaust outlet flow path;
- and
- a compositional sensor disposed in the exhaust outlet flow path at a position downstream of the diagnostic SCR catalyst element, the compositional sensor structured to determine one of an NH3 concentration and a NOx concentration in the exhaust outlet flow path.
A system, comprising:
- an internal combustion engine producing an exhaust gas stream as a byproduct of operation;
- an SCR catalyst element receiving at least a portion of the exhaust gas stream, the SCR catalyst element divided into at least two portions;
- an exhaust outlet flow path having an inlet fluidly coupled to the exhaust gas stream at a position between two of the at least two portions of the SCR catalyst element;
- a diagnostic SCR catalyst element receiving a portion of the exhaust gas stream through the exhaust outlet flow path;
- a compositional sensor disposed in the exhaust outlet flow path at a position downstream of the diagnostic SCR catalyst element, the compositional sensor structured to determine one of an NH3 concentration and a NOx concentration in the exhaust outlet flow path.
A method, comprising:
- receiving a portion of an exhaust gas stream into an exhaust outlet flow path;
- treating the removed portion with a diagnostic SCR catalyst element;
- determining a composition of the treated removed portion, wherein the determining comprises determining at least one of an NH3 concentration and a NOx concentration.
An apparatus, comprising:
- a diagnostic SCR catalyst element positioned in an exhaust outlet flow path that receives a portion of an exhaust gas stream from a main flow of exhaust, wherein the diagnostic SCR catalyst element is structured to treat the portion of the exhaust gas stream passing therethrough;
- a sensor operationally coupled to the treated portion of the exhaust gas stream and providing a composition signal representative of a composition of the treated portion;
- and
- an NH3 determination module structured to determine an excess NH3 amount in response to the composition signal.
Dependencies are inferred from the claim text.