| 摘要 |
<p>A method of controlling exhaust emission, comprising the steps of providing a first heat resistant filter medium in the exhaust emission passage of an internal combustion engine to collect hydrocarbon compounds and carbon-containing suspended particles contained in the exhaust emission distributedly so as to be brought into contact with the oxygen contained in the exhaust emission, burning the collected hydrocarbon compounds and carbon-containing suspended particles by using the exhaust emission with an inflow temperature lower than the inflammable temperature of the carbon-containing suspended particles, and providing a second heat resistant filter medium on the downstream side of the first heat resistant filter medium to collect the carbon-containing suspended particles passed through the heat resistant filter medium without being collected by the first filter medium, whereby the purification rate of the particles can be increased and, because most particles are filtrated by the first filter medium, the second filter medium can maintain a high purification rate over a long period of time.</p> |
