SNCR Energy Abbreviation

Selective Noncatalytic Reduction

Selective Noncatalytic Reduction (SNCR) is a method used to reduce nitrogen oxide (NOx) emissions from combustion sources such as power plants, industrial boilers, and waste incinerators. This process involves injecting a nitrogen-containing chemical reagent, such as ammonia or urea, into the flue gas stream at a high temperature without the use of a catalyst. The reagent reacts with NOx to form nitrogen and water vapor, which are harmless and released into the atmosphere. SNCR is favored for its simplicity and cost-effectiveness, especially in applications where the installation of a catalytic system is not feasible or economical.

The effectiveness of SNCR depends on several factors, including the temperature window in which the reaction occurs, the residence time of the reagent in the flue gas, and the mixing of the reagent with the NOx. Typically, the optimal temperature range for SNCR is between 900°C and 1100°C. Outside this range, the reaction efficiency drops significantly, leading to lower NOx reduction rates. Despite its advantages, SNCR has limitations, such as lower NOx reduction efficiency compared to Selective Catalytic Reduction (SCR) and the potential for ammonia slip, where unreacted ammonia is released into the atmosphere.