Boldrocchi succeeded in obtaining impressive NOX reduction rates by using Selective Non-Catalytic Reduction (SNCR) in a Lepol cement kiln at the Isola delle Femmine plant. We were able to reduce NOX to 350 mg/Nm3, translating into an efficiency of > 60%, rivaling the best abatement possible with SNCR. The injection point was chosen where there was an optimal flue gas temperature window (850°C – 1000°C) to ensure reaction efficiency.
Currently in Europe, SNCR is used in over 100 cement kiln plants. In this specific project, Boldrocchi used reagent with an ammonia content of 24,5 ± 0,4 % NH3 and maximum flowrate of 525 l/h and succeeded in reducing NOX to 350 mg/Nm3. These abatement results are impressive as SNCR is often only able to attain between 350 and 400 mg/Nm3 at best. For this kiln, the numbers mean an efficiency of > 60% (SNCR in general offers an efficiency between 30 and 65%, depending on the reagent, the amount of it and the temperature, along with other process parameters.)
Scope of supply:
Main process data:
Reagent: Ammonia Solution (NH4OH)
Ammonia content: 24,5 ± 0,4 % NH3
Max flowrate NH4OH: 525 l/h
Flue gas T° at injection point: 850 ÷ 1100°C
NOX after SNCR system: up to 350 mg/Nm3 corresponding to efficiency > 60%
Read more about Boldrocchi’s DeNOX technologies in our article “Eradicating NOX” in World Cement’s April 2018 issue.