Patent · US Expired

Exhaust aftertreatment system

US7051521B2 · kind B2 · utility

5Cited by
9References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 25, 2005
Grant dateMay 30, 2006
Priority date
Expiry dateJan 25, 2025

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/12
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

A particulate filter integrally carrying an oxidation catalyst is arranged in an exhaust pipe through which exhaust gas from a diesel engine flows. A NOx-absorption reduction catalyst is arranged in the exhaust pipe and downstream of the particulate filter. A bypass line is branched from a portion of the exhaust pipe between the particulate filter and the reduction catalyst and is connected to a portion of the exhaust pipe downstream of the reduction catalyst. A selector valve is arranged at the branch point of the bypass line and may be switched over to guide the exhaust gas either to the reduction catalyst or to the bypass line. As a result, without difficultly controlling the operation of the diesel engine, the reduction catalyst is prevented from being poisoned and deteriorated by sulfate, the lowering of the ratio of NOx purification through the NOx-absorption reduction catalyst is averted and prolongation of its life is attained.

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