Patent ID: 6173568
Filing Date: 2001-01-16
Classification: B01D,F01N,Y02T

Abstract:
A method of operating an internal combustion engine running with an excess of air, which comprises:conducting an exhaust gas flow through a main exhaust pipe and through a NO.sub.x catalytic converter unit having at least an SCR catalytic converter and a device for injecting reducing agent into the exhaust gas flow;constantly determining a load state of the internal combustion engine during the conducting step;if the load of the internal combustion engine increases rapidly, diverting at least part of the exhaust gas flow via a bypass system and to an adsorption catalytic converter;if the internal combustion engine is in warmup operation, diverting at least part of the exhaust gas flow via a bypass system and to an adsorption catalytic converter; andguiding the exhaust gas flowing through the bypass system through the adsorption catalytic converter and the SCR catalytic converter.