| 摘要 |
PURPOSE:To provide a method for purifying a large volume of air containing a small amount of NOx efficiently. CONSTITUTION:Air containing a small amount of NOx is guided to an adsorption tower 16 to have NOx removed by adsorption and the air is discharged into an atmosphere as a purified gas 6. On the other hand, the adsorbed NOx is desorbed in the adsorption tower 17 which has adsorbed NOx previously. Next, the desorbed NOx gas 8 is heated by a heat exchanger 11, and hydrocarbon 12 which becomes a reducing gas is added to the NOx gas 8 to be guided to an NOx decomposition tower 18 where NOx is decomposed into N2 and O2 action of hydrocarbon. The outlet gas 14 of the NOx decomposition tower 18 passes through the heat exchanger 11, being sent to an NOx concentration step as recycled gas 5. |
