Method for treatment of exhaust gases

Patent · Tue Apr 17 04:00:00 EDT 1990

OSTI ID:6726973

Gandhi, H S; Kummer, J T

This patent describes a method of treating exhaust gases from an engine variably operated at rich and at stoichiometric air/fuel ratios. The exhaust gas flowing from the engine through an exhaust manifold and thence through an exhaust pipe containing an oxidation catalytic converter, the catalytic converter being effective to reduce CO, HC, and NO{sub x} constituents of the exhaust gas. It comprises: introducing secondary air to the exhaust gas, both at the exhaust manifold and at a location adjacent and upstream of the catalytic converter, the air being introduced in a predetermined controlled quantity effective to create a reducing condition for the exhaust gas as it enters the catalyst during rich operating air/fuel rations of the engine to oxidize 80-95 mole percent of CO while substantially oxidizing all NO{sub x} and HC, and to create, with the same predetermined quantity of air, and oxidizing condition for the exhaust gas as it enters the catalyst during substantially stoichiometric operating air/fuel ratios for the engine to oxidize substantially all CO and HC.

• Assignee: Ford Motor Co., Dearborn, MI (USA)
• Patent Number(s): A; US 4916898
• Application Number: PPN: US 6-715691A
• OSTI ID: 6726973
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330700* -- Advanced Propulsion Systems-- Emission Control
54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR POLLUTION CONTROL
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYTIC CONVERTERS
CHALCOGENIDES
CONTROL
ENGINES
EQUIPMENT
EXHAUST GASES
FLUIDS
FUEL-AIR RATIO
GASEOUS WASTES
GASES
HEAT ENGINES
HYDROCARBONS
INTERNAL COMBUSTION ENGINES
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL
POLLUTION CONTROL EQUIPMENT
WASTES