| 摘要 |
PURPOSE:To directly decompose NOx by a small amount of a catalyst without adding a reducing agent by purging NOx concentrated by an adsorbent using N2 gas to desorb the same. CONSTITUTION:Air 1 is guided to a dust extractor 3 by a blower 2 to remove soot in air and the recycle gas 5 from an NOx concentration tower 19 is added to the treated air to be supplied to an NOx adsorption tower 17. Whereupon, almost all of NOx is adsorbed and removed to discharge clean gas 6. An NOx desorption tower 18 is reduced in pressure to desorb NOx to a gas side and the recycle gas 16 from an NOx decomposing process is added to desorbed NOx to be supplied to the NOx concentration tower 19 as NOx gas 8. Almost all of NOx is absorbed and the removed in the NOx concentration tower 19 and NOx is desorbed under vacuum in a concentrated NOx desorbing tower 20 and subjected to heat exchange and decomposed into nitrogen and oxygen in an NOx decomposition tower 21 packed with an NOx decomposing catalyst. By this constitution, efficient purification is performed. |
