| 摘要 |
A method of cleansing nitrogen oxide (NOx), hydrocarbon (HC) and carbon monoxide (CO) from waste gases, such as the waste gases or exhaust gases originating from burners and internal combustion engines. The waste gases, or exhaust gases, are passed through a catalyst for catalytic cleansing of the gases. The air-fuel ratio, or the lambda value (L), is reduced to a level below L=1. The gases are passed through a first catalyst and then through a second catalyst, to bring the CO-content of the gas in the first catalyst to a sufficiently high level and to reduce NOx to N2 to an extent such as to bring the NOx content down to a predetermined level. Sufficient oxygen (O2) is delivered to the gases at a point between the first and second catalysts to oxidize both CO and HC to CO2 and H2O to such an extent as to reduce the CO-content of the gas to a predetermined level. A gas burner to carry out the method is also disclosed. |
