Exhaust gas purification system for lean burn engine

Patent · Tue Feb 19 04:00:00 EST 2002

OSTI ID:874239

Haines, Leland Milburn ^[1]

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1. Northville, MI

An exhaust gas purification system for a lean burn engine includes a thermal mass unit and a NO.sub.x conversion catalyst unit downstream of the thermal mass unit. The NO.sub.x conversion catalyst unit includes at least one catalyst section. Each catalyst section includes a catalytic layer for converting NO.sub.x coupled to a heat exchanger. The heat exchanger portion of the catalyst section acts to maintain the catalytic layer substantially at a desired temperature and cools the exhaust gas flowing from the catalytic layer into the next catalytic section in the series. In a further aspect of the invention, the exhaust gas purification system includes a dual length exhaust pipe upstream of the NO.sub.x conversion catalyst unit. The dual length exhaust pipe includes a second heat exchanger which functions to maintain the temperature of the exhaust gas flowing into the thermal mass downstream near a desired average temperature.

• Research Organization: Midwest Research Institute
• DOE Contract Number: AC36-83CH10093
• Assignee: Ford Global Technologies, Inc. (Dearborn, MI)
• Patent Number(s): US 6347511
• Application Number: 09/469,040
• OSTI ID: 874239
• Country of Publication: United States
• Language: English

Related Subjects

/60/422/
aspect
average
burn
catalyst
catalytic
conversion
converting
cools
coupled
downstream
dual
engine
exchanger
exhaust
exhaust gas
flowing
functions
gas
gas flow
heat
heat exchanger
layer
lean
lean burn
length
maintain
mass
near
nosubx
pipe
portion
purification
section
series
substantially
temperature
thermal
thermal mass
unit
upstream