SNCR process (Selective non catalytic reduction)

The SNCR deNOx process consists of injecting a reagent at the furnace outlet to reduce the nitrogen oxides at a temperature of 900°C to 1000°C.

The following reagents are used for this process :

Urea pellets with a special injection nozzle;
Liquid urea;
Ammonia.

High performances require excess ammonia injection which can impede capture in dry and semi-dry processes or pollute the liquid bleed in wet processes. Stripping the scrubbing water then makes it possible to recycle at the boiler inlet the excess ammonia from the gases.

Non-catalytic type (SNCR) reduction system