Patent · US Expired

Adsorber aftertreatment system having downstream soot filter

US6820414B2 · kind B2 · utility

20Cited by
32References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 11, 2002
Grant dateNov 23, 2004
Priority date
Expiry dateJul 11, 2022

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF01N2410/12
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

The present invention provides for adsorber catalysts arranged in parallel. The exhaust flow from the engine is divided in a predetermined ratio between the two catalysts during lean operation (e.g. 50-50). At a predetermined regeneration time (for example, when the adsorber catalyst is 20% full), the exhaust gas flow is reduced through the parallel leg that is to be regenerated (e.g. 20-80). A quantity of hydrocarbon is injected into the reduced-flow leg in order to make the mixture rich. Once the leg has been regenerated, the flow distribution between the parallel legs is reversed, and the other catalyst leg is regenerated while the other side (which is now clean) receives the majority of the exhaust flow. Once both catalyst legs have been regenerated, the exhaust flow is adjusted back to normal (e.g. 50-50) until the catalysts are again ready for regeneration and reduction. A catalytic soot filter is positioned downstream from the adsorber. The heat generated by the regenerating adsorber is transferred downstream to the soot filter, thereby heating the soot filter above the temperature required for regeneration. Additionally, any hydrocarbon that slips through the adsorber is bu…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.