| 摘要 |
<p>Selective removal of nitrogen oxides in the waste gas of furnaces. Nitrogen oxides are reduced to molecular nitrogen by the addition of ammonia to the waste gases and accelerating the reaction by a catalyst. The procedure is to feed the waste gases through the catalyst in one zone and, in another zone separated from this, to feed the fresh air which is to be fed into the furnace as combustion air. The location of the zones which are traversed by the flow of the waste gases or fresh air are continually or progressively modified in such a way that the zones which were previously traversed by the waste gases are then traversed by fresh air, and vice versa. The ammonia is mixed with the fresh air before its entry into the catalyst, combined on the surface of the catalytically operating material and then entrained into the zone traversed by the waste gases, where the reduction of nitrogen oxide then takes place.</p> |
