| 摘要 |
An apparatus and method for oxidizing hydrocarbons in gases exhausted from an internal combustion engine 10. The method comprises passing exhaust gases, during initial operation of the engine, through a hydrocarbon trap 24, where the hydrocarbons in the exhaust gases are adsorbed before the gases are exhausted into the atmosphere. After a catalyst 16 is heated to the light-off temperature for hydrocarbons, the gases are prevented from passing through the hydrocarbon trap 24 and are passed through the catalyst 16 before being exhausted into the atmosphere. When the engine 10 speed is at steady state, such that the oxidation of hydrocarbons by the catalyst 16 is at peak efficiency, a portion of the gases exiting the catalyst 16 is diverted to pass through and flush hydrocarbons from the hydrocarbon trap 24 while the remaining gas is exhausted into the atmosphere. The diverted gases containing the flushed hydrocarbons desorbed from the hydrocarbon trap 24 are then passed through the catalyst 16. After the hydrocarbons have been desorbed from the hydrocarbon trap 24, all gases passing through the catalyst 16 are exhausted into the atmosphere. |
