Selective non-catalytic reduction (SNCR) method is a cost effective solution for secondary NOx emission control. The SNCR method is an ammonia or urea injection system that reduces NOx emissions. NOx reduction achieved with this method depends on the boiler design and load. Typical reduction varies from 20% to 70%.
Reducing NOx emissions In SNCR, ammonia or urea is injected straight into the furnace or cyclone inlet and mixed with the hot flue gas. Ammonia reacts with nitrogen oxides to produce water and nitrogen.