Patent · US Expired

Reducing NO.sub.x emissions from an engine while maximizing fuel economy

US5924280A · kind A · utility

123Cited by
14References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 4, 1997
Grant dateJul 20, 1999
Priority date
Expiry dateApr 4, 2017

Classification

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

Abstract

Exhaust gas recirculation and selective catalytic reduction with urea or other NO.sub.x - reducing reagent are employed to enable good fuel economy and low emissions from diesel and lean-burn gasoline engines. EGR is operated at low-load, as well as when problems are experienced with reagent supply or the SCR unit. The SCR is run at its optimum operating conditions of normal to high load, supplanting the need for EGR. The net effect is a circumvention of the known tradeoff between NO.sub.x and poor fuel economy. The novel application of SCR and EGR in combination will provide engines that meet low emissions requirements with existing technology.

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