Method and apparatus for reducing hydrocarbon emissions for an internal combustion engine

摘要

In a method and apparatus for reducing hydrocarbon emissions from an internal combustion engine during its cold-starting phase an adsorber, which adsorbs hydrocarbons below a desorption temperature and desorbs them above the desorption temperature, is arranged in a bypass conduit to the exhaust conduit and the exhaust gas is passed through the bypass conduit and the adsorber below the desorption temperature of the adsorber, and the bypass conduit is closed when a catalytic converter arranged close the engine in the exhaust conduit upstream of the bypass conduit reaches operating temperature and remains closed at least until a catalytic converter arranged downstream of the adsorber has reached operating temperature.