Exhaust system for lean burn IC engines
US7178331B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 2003 |
| Grant date | Feb 20, 2007 |
| Priority date | — |
| Expiry date | Sep 3, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An exhaust system (10) for a lean-burn internal combustion engine comprises a nitrogen oxide (NOx) absorbent (28), a catalyst (30) for catalyzing the selective catalytic reduction (SCR) of a NOx with a NOx specific reactant, first means (18, 22) for introducing a NOx specific reactant or a precursor thereof into an exhaust gas upstream of the SCR catalyst (30) and means (24) for controlling the introduction of the NOx-specific reactant or precursor thereof into the exhaust gas via the first introducing means (18, 22), wherein the SCR catalyst (30) is disposed upstream of the NOx absorbent (28) and optionally with the NOx absorbent, wherein the control means (24) is arranged to introduce the NOx-specific reactant or the precursor thereof to exhaust gas via the first introducing means (18, 22) only when the SCR catalyst (30) is active, whereby exhaustion of NOx-specific reactant to atmosphere is substantially prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.